Claims:WE CLAIM:

1. An actuation arrangement (90) for redundancy configurations, comprising:

a logic chamber (115) having at least four co-axial cylindrical chambers (116-119) each of different diameter, holding a first piston (107) in a first chamber (116), a second piston (106) in a second chamber (117), a third piston (105) in a third chamber (118) and a fourth piston (104) in a fourth chamber (119),

wherein the first piston (107), the second piston (106), the third piston (105) and the fourth piston (104) are disposed on a common piston bar (114),

wherein the co-axial cylindrical chambers (116-119) comprise the first chamber (116) with a first inlet port (123), the second chamber (117) with a second inlet port (124), the third chamber (118) with a third inlet port (125) and the fourth chamber (119),

wherein a face II (107b) of the first piston (107) and a face I (106a) of the second piston (106) form parts of a first pocket (120), a face II (106b) of the second piston (106) and a face I (105a) of the third piston (105) form parts of a second pocket (121) and a face II (105b) of the third piston (105) and a face I (104a) of the fourth piston (104) form parts of a third pocket (122), and

wherein the common piston bar (114) extending from a first end (132) has an interacting end (131);

a counterbalance chamber (110) with an incoming connection (126) having a moving surface (108) and a mechanical energy accumulator, wherein the mechanical energy accumulator is a pre-loaded compression spring (109),

wherein one end of the pre-loaded compression spring (109) is fixed axially to a face I (108a) of the moving surface (108) and other end is fixed axially to a rigid side (143) of the counterbalance chamber (110); and

a commensurate two position switching device (145) having a means to connect to the logic chamber (115) on a one end and to the counterbalance chamber (110) on the other end;

such that the two position switching device (145) takes either a first position towards the counterbalance chamber (110) or a second position towards the logic chamber (115) depending on a direction of a resultant force Fr.

2. A valve actuation arrangement (100) for “2-out-of-3” system, comprising:

three enabling devices;

a logic chamber (115) having at least four co-axial cylindrical chambers (116-119) of different diameters, holding a first piston (107) in a first chamber (116), a second piston (106) in a second chamber (117), a third piston (105) in a third chamber (118) and a fourth piston (104) in a fourth chamber (119),

wherein the first piston (107), the second piston (106), the third piston (105) and the fourth piston (104) are disposed on a common piston bar (114),

wherein the co-axial cylindrical chambers (116-119) comprise the first chamber (116) with a first inlet port (123), the second chamber (117) with a second inlet port (124), the third chamber (118) with a third inlet port (125) and the fourth chamber (119),

wherein a face II (107b) of the first piston (107) and a face I (106a) of the second piston (106) form parts of a first pocket (120), a face II (106b) of the second piston (106) and a face I (105a) of the third piston (105) form parts of a second pocket (121) and a face II (105b) of the third piston (105) and a face I (104a) of the fourth piston (104) form parts of a third pocket (122), and

wherein the common piston bar (114) extending from a first end (132) has an interacting end (131);

a three-port two-position valve (127) having an inlet port (111), an exhaust port (112) and an outlet port (113) further comprising a first transverse wall (128), a second transverse wall (129) and a third transverse wall (137) interconnected through an axially movable rod (130),

wherein a free end (134) of the axially movable rod (130) projects out from a rod side (133),

wherein a first face (138) of the axially movable rod (130) projects out from a face side (137a) of the third transverse wall (137) of the three-port two-position valve (127),

wherein the first transverse wall (128) and the second transverse wall (129) are located in such a way that when the axially movable rod (130) is in a position X, the first transverse wall (128) and the second transverse wall (129) connect the outlet port (113) with the exhaust port (112), and

wherein the first transverse wall (128) and the second transverse wall (129) are located in such a way that when the axially movable rod (130) is in a position Y, the first transverse wall (128) and the second transverse wall (129) connect the outlet port (113) with the inlet port (111); and

a counterbalance chamber (110) with an incoming connection (126), having a moving surface (108) and a mechanical energy accumulator, wherein the mechanical energy accumulator is a pre-loaded compression spring (109),

wherein one end of the pre-loaded compression spring (109) is fixed axially to a face I (108a) of the moving surface (108) and other end is fixed axially to a rigid side (143) of the counterbalance chamber (110);

the free end (134) projecting out from the rod side (133) of the three-port two-position valve (127) is connected axially with the interacting end (131) projected out from the first end (132) of the common piston bar (114), the first face (138) of the axially movable rod (130) projected out from the face side (137a) of the third transverse wall (137) is connected axially with the face II (108b) of the moving surface (108) of the counterbalance chamber (110), a hydraulic or pneumatic supply (142) interconnecting all the three enabling devices, the incoming connection (126) of the counter balance chamber (110) and the inlet port (111) of the three-port two-position valve (127), the hydraulic or pneumatic supply (142) constantly available to the incoming connection (126) of the counter balance chamber (110), the pre-loaded compression spring (109) exerts a force Fm on the moving surface (108), aided with a force F4 due to the hydraulic or pneumatic pressure constantly available from the hydraulic or pneumatic supply (142) to the incoming connection (126) of the counter balance chamber (110), when none of the three enabling devices are active then the axially movable rod (130) is in the position X, when one of the enabling devices is active then the axially movable rod (130) is in the position X, and when at least two enabling devices are active then the axially movable rod (130) is in the position Y, thus achieving a “2-out-of-3” configuration.
3. A valve actuation arrangement (100a) for “1-out-of-2” system, comprising:

two enabling devices;

a logic chamber (115a) having at least three co-axial cylindrical chambers (116-118) of different diameters, holding a first piston (107) in a first chamber (116), a second piston (106) in a second chamber (117), and a third piston (105) in a third chamber (118),

wherein the first piston (107), the second piston (106), and the third piston (105) are disposed on a common piston bar (114),

wherein the co-axial cylindrical chambers (116-118) comprise the first chamber (116) with a first inlet port (123), the second chamber (117) with a second inlet port (124), and the third chamber (118),

wherein a face II (107b) of the first piston (107) and a face I (106a) of the second piston (106) form parts of a first pocket (120), and a face II (106b) of the second piston (106) and a face I (105a) of the third piston (105) form parts of a second pocket (121), and

wherein the common piston bar (114) extending from a first end (132) has an interacting end (131);

a three-port two-position valve (127) having an inlet port (111), an exhaust port (112) and an outlet port (113) further comprising a first transverse wall (128), a second transverse wall (129) and a third transverse wall (137) interconnected through an axially movable rod (130),

wherein a free end (134) of the axially movable rod (130) projects out from a rod side (133),

wherein a first face (138) of the axially movable rod (130) projects out from a face side (137a) of the third transverse wall (137) of the three-port two-position valve (127),

wherein the first transverse wall (128) and the second transverse wall (129) are located in such a way that when the axially movable rod (130) is in a position X, the first transverse wall (128) and the second transverse wall (129) connect the outlet port (113) with the exhaust port (112), and

wherein the first transverse wall (128) and the second transverse wall (129) are located in such a way that when the axially movable rod (130) is in a position Y, the first transverse wall (128) and the second transverse wall (129) connect the outlet port (113) with the inlet port (111); and

a counterbalance chamber (110) with an incoming connection (126), having a moving surface (108) and a mechanical energy accumulator, wherein the mechanical energy accumulator is a pre-loaded compression spring (109),

wherein one end of the pre-loaded compression spring (109) is fixed axially to a face I (108a) of the moving surface (108) and other end is fixed axially to a rigid side (143) of the counterbalance chamber (110);

the free end (134) projecting out from the rod side (133) of the three-port two-position valve (127) is connected axially with the interacting end (131) projected out from the first end (132) of the common piston bar (114), the first face (138) of the axially movable rod (130) projected out from the face side (137a) of the third transverse wall (137) is connected axially with the face II (108b) of the moving surface (108) of the counterbalance chamber (110), a hydraulic or pneumatic supply (142) interconnecting the two enabling devices, the incoming connection (126) of the counter balance chamber (110) and the inlet port (111) of the three-port two-position valve (127), the hydraulic or pneumatic supply (142) constantly available to the incoming connection (126) of the counter balance chamber (110), the pre-loaded compression spring (109) exerts a force Fm on the moving surface (108), aided with a force F4 due to the hydraulic or pneumatic pressure constantly available from the hydraulic or pneumatic supply (142) to the incoming connection (126) of the counter balance chamber (110), when neither of the enabling devices are active then the axially movable rod (130) is in the position X, when one of the enabling devices is active then the axially movable rod (130) is in the position X, and when both of the enabling devices are active then the axially movable rod (130) is in the position Y, thus achieving a “1-out-of-2” configuration.
4. A valve actuation arrangement (100b) for “2-out-of-2” system, comprising:

two enabling devices;

a logic chamber (115b) having at least four co-axial cylindrical chambers (116-119) of different diameters, holding a first piston (107) in a first chamber (116) and a third piston (105) in a third chamber (118),

wherein the first piston (107) and the third piston (105) are disposed on a common piston bar (114),

wherein the co-axial cylindrical chambers (116-119) comprise the first chamber (116) with a first inlet port (123) and the third chamber (118) with a last inlet port (125L),

wherein a face II (107b) of the first piston (107) and a face I (105a) of the third piston (105) form parts of a first pocket (120), and a face II (105b) of the third piston (105) and an end wall (99) of the logic chamber (115b) form parts of a last pocket (122L), and

wherein the common piston bar (114) extending from a first end (132) has an interacting end (131);

a three-port two-position valve (127) having an inlet port (111), an exhaust port (112) and an outlet port (113) further comprising a first transverse wall (128), a second transverse wall (129) and a third transverse wall (137) interconnected through an axially movable rod (130),

wherein a free end (134) of the axially movable rod (130) projects out from a rod side (133),

wherein a first face (138) of the axially movable rod (130) projects out from a face side (137a) of the third transverse wall (137) of the three-port two-position valve (127),

wherein the first transverse wall (128) and the second transverse wall (129) are located in such a way that when the axially movable rod (130) is in a position X, the first transverse wall (128) and the second transverse wall (129) connect the outlet port (113) with the exhaust port (112), and

wherein the first transverse wall (128) and the second transverse wall (129) are located in such a way that when the axially movable rod (130) is in a position Y, the first transverse wall (128) and the second transverse wall (129) connect the outlet port (113) with the inlet port (111); and

a counterbalance chamber (110) with an incoming connection (126), having a moving surface (108) and a mechanical energy accumulator, wherein the mechanical energy accumulator is a pre-loaded compression spring (109),

wherein one end of the pre-loaded compression spring (109) is fixed axially to a face I (108a) of the moving surface (108) and other end is fixed axially to a rigid side (143) of the counterbalance chamber (110);

the free end (134) projecting out from the rod side (133) of the three-port two-position valve (127) is connected axially with the interacting end (131) projected out from the first end (132) of the common piston bar (114), the first face (138) of the axially movable rod (130) projected out from the face side (137a) of the third transverse wall (137) is connected axially with the face II (108b) of the moving surface (108) of the counterbalance chamber (110), a hydraulic or pneumatic supply (142) interconnecting the two enabling devices, the incoming connection (126) of the counter balance chamber (110) and the inlet port (111) of the three-port two-position valve (127), the hydraulic or pneumatic supply (142) constantly available to the incoming connection (126) of the counter balance chamber (110), the pre-loaded compression spring (109) exerts a force Fm on the moving surface (108), aided with a force F4 due to the hydraulic or pneumatic pressure constantly available from the hydraulic or pneumatic supply (142) to the incoming connection (126) of the counter balance chamber (110), when neither of the enabling devices are active then the axially movable rod (130) is in the position X, when one of the enabling devices is active then the axially movable rod (130) is in the position Y, and when both of the enabling devices are active then the axially movable rod (130) is in the position Y, thus achieving a “2-out-of-2” configuration.
5. The valve actuation arrangement (100, 100a, 100b) of claim 2 or 3 or 4, wherein the enabling device is any one of a manually operated lever or a push button or a pressure operated valve or solenoid operated valves (101-103) used to supply the hydraulic or pneumatic pressure to the logic chamber (115, 115a, 115b).

6. The actuation arrangement (90) or the valve actuation arrangement (100, 100a, 100b) of claims 1 or 2 or 3 or 4, wherein the first chamber (116) has a diameter larger than the second chamber (117), the second chamber (117) has a diameter larger than the third chamber (118) and the third chamber (118) has a diameter larger than the fourth chamber (119).

7. The valve actuation arrangement (100, 100a, 100b) of claim 2 or 3 or 4, wherein the three-port two-position valve (127) is replaced by a five-port, three-port or a two-port valve.

8. The actuation arrangement (90) of claim 1, wherein at least two of the logic chamber (115), the two position switching device (145) and the counterbalance chamber (110) are an integral device.

9. The valve actuation arrangement (100, 100a, 100b) of claim 2 or 3 or 4, wherein at least two of the logic chamber (115, 115a, 115b), the three-port two-position valve (127) and the counterbalance chamber (110) are an integral device.

10. The actuation arrangement (90) or the valve actuation arrangement (100, 100a, 100b) of claims 1 or 2 or 3 or 4, wherein the logic chamber (115, 115a, 115b) has a pressure sensor (139) connected to the first pocket (120), a pressure sensor (140) connected to the second pocket (121) and a pressure sensor (141) connected to the third pocket (122) or the last pocket (122L).

11. The valve actuation arrangement (100, 100a, 100b) of claim 2 or 3 or 4, wherein the hydraulic or pneumatic supply (142) to the at least two enabling devices, the counter balance chamber (110) and the three-port two-position valve (127) is from a common source.

12. The valve actuation arrangement (100, 100a, 100b) of claim 2 or 3 or 4, wherein the hydraulic or pneumatic supply (142) to the at least two enabling devices, the counter balance chamber (110) and the three-port two-position valve (127) is not from a common source.

13. The actuation arrangement (90) or the valve actuation arrangement (100, 100a, 100b) of claim 10, wherein the pressure sensor (139-141) represents an operating state of corresponding enabling device.
, Description:Form 2
The Patent Act 1970
(39 of 1970)
&
The Patent Rules 3
Complete Specification
(See section 10 and rule 13)
Title of the Invention:

AN ACTUATION ARRANGEMENT FOR “2-OUT-OF-3” SYSTEM AND OTHER REDUNDANCY CONFIGURATIONS

Applicant: Rotex Automation Limited
Nationality: Indian
Address: 987/11, GIDC, Makarpura,
Vadodara – 390010
Gujarat, India

The following specification particularly describes the invention and the manner in which it is to be performed.
FIELD OF INVENTION
[0001] The present invention relates to fluid control valves and particularly to actuation of fluid control valves and other devices therefrom as per process requirement in process automation and control systems.
BACKGROUND
[0002] Valves are used to control hydraulic or pneumatic flow. There is a large applicability of control valves in the industry in switching cylinders, fluid power motors or larger industrial valves. To avoid discontinuity in operation of the system, it is desirable to test working of the valves without any interruption.
[0003] There are various configurations in which the valves can be actuated. In “1-out-of-1” configuration, only one solenoid valve is on-line during normal operation. In “1-out-of-2” configuration, any one out of the two solenoid valves needs to be switched-off to switch the cylinder and maintain safe system. In “2-out-of-2” configuration, both the valves need to be switched-off to switch the cylinder. This configuration provides availability. To avail facility of both high safety and availability, a “2-out-of-3” configuration is applied, wherein two out of three valves must be switched-off to switch the cylinder. The conventional method of achieving “2-out-of-3” configuration is by deploying four number three-port two-position valves, therefore also known as a quad voting system since, by connecting three valves in series or parallel or in any permutation, “2-out-of-3” configuration is not industrially achievable. The quad voting configuration, wherein four valves are deployed, has reduced reliability and additional components are needed to get feedback of each valve. This increases cost and maintenance and has ambiguity related to visual indication and interpretation. In addition, at hazardous or explosive environments, deploying more number of valves and barriers further increases cost and reduces safety. Another method of achieving “2-out-of-3” configuration is by deploying three number 5-port 2-position valves by which “2-out-of-3” is successfully achieved but has ambiguities related to visual indication and interpretation.
[0004] In other existing actuation arrangements, six valves are interconnected by generous sized drain or dump passageways for “2-out-of-3” logic circuit such that the failure of any one of the valves will not affect correct operation of the other two and of the trip mechanism. This further adds to cost and maintenance of the system and aggravates visual indication and interpretation confusions.
[0005] Therefore, there is a need for a system that provides high safety, reliable operation with truly relevant visual indication output and having low cost.
[0006] Further, for different redundant configurations like 1-out-of-2, 2-out-of-2, et cetera, different tubings and parts are used which reduces manufacturing flexibility and increases cost.
[0007] It is therefore also desirable that a system be such that could also be deployed for other redundant configurations with little or no modification.

OBJECTIVES OF THE INVENTION
[0008] An objective of a present invention is to provide an actuation arrangement that operates in “2-out-of-3” configuration.
[0009] Another objective of the present invention is to provide the actuation arrangement that deploys only three enabling devices, like valves, to achieve “2-out-of-3” configuration.
[0010] Another objective of the present invention is to mitigate the necessity of using more than three enabling devices, like valves, in order to achieve “2-out-of-3” configuration.
[0011] Another objective of the present invention is to provide a low-cost actuation arrangement that offers higher reliability and avoids absurd situations.
[0012] Another objective of the present invention is to provide simplified signal to a user by which an operating state of the enabling devices, like valves, can be unambiguously interpreted.
[0013] Another objective of present invention is to provide an actuation arrangement that can also be deployed for “1-out-of-2” and “2-out-of-2” configuration with minimal modification.

SUMMARY
[0014] An actuation arrangement having a two position switching device, a logic chamber and a counter balance chamber. The commensurate two position switching device has a means to connect to the logic chamber on one end and to the counterbalance chamber on the other end such that the two position switching device takes either a first position towards the counterbalance chamber and a second position towards the logic chamber depending on the direction of a resultant force Fr.
[0015] The preferred embodiment of present invention is a valve actuation arrangement with three enabling devices for “2-out-of-3” configuration. While all illustrations and explanation here below is with solenoid operated valves to represent three enabling devices particularly fluidic pressure enabling devices, however levers, push buttons, pressure operated valves or any enabling devices or particularly fluidic pressure enabling devices may be deployed. Thus, the valve actuation arrangement as per present invention has a first solenoid operated valve, a second solenoid operated valve and a third solenoid operated valve for achieving a true “2-out-of-3” system, and comprises a three-port two-position valve representing the two position switching device, the logic chamber, and the counterbalance chamber pneumatically or hydraulically interconnected with the three solenoid operated valves.
[0016] The logic chamber has at least four co-axial cylindrical chambers. The embodiment considers cylindrical chambers but they could be of any cross section. A first chamber has a diameter larger than a second chamber, the second chamber has a diameter larger than a third chamber and the third chamber has a diameter larger than a fourth chamber. The first chamber has a first inlet port, the second chamber has a second inlet port and the third chamber has a third inlet port. Each of these cylindrical chambers may have an exhaust port and port for connecting pressure sensors and or visual indicators. The first chamber has a first piston, the second chamber has a second piston, the third chamber has a third piston and the fourth chamber has a fourth piston. The first piston has a face I and a face II, the second piston has a face I and a face II, the third piston has a face I and a face II, and likewise the fourth piston has a face I and a face II.
[0017] The face II of the first piston and the face I of the second piston form parts of a first pocket, the face II of the second piston and the face I of the third piston form parts of a second pocket, the face II of the third piston and the face I of the fourth piston form parts of a third pocket. The first pocket comprises partly of the first chamber and partly of the second chamber. The second pocket comprises partly of the second chamber and partly of the third chamber. Likewise, the third pocket comprises partly of the third chamber and partly of the fourth chamber. The pressure sensors and or visual indicators are connected to the first pocket, the second pocket and the third pocket respectively. These pressure sensors and or visual indicators indicate the operating states of the solenoid operated valves when energized or de-energized.
[0018] The first piston, the second piston, the third piston and the fourth piston are disposed on a common piston bar. The common piston bar has an interacting end extending from a first end of the logic chamber.
[0019] The three-port two-position valve has an inlet port, an outlet port and an exhaust port. The three-port two-position valve further holds an axially movable rod that connects a first transverse wall, a second transverse wall and a third transverse wall, the first and the second transverse walls are located such that when the axially movable rod is in a position X, the first transverse wall and the second transverse wall connect the outlet port with the exhaust port and when the axially movable rod is in a position Y then the first transverse wall and the second transverse wall connect the inlet port with the outlet port. A first face of the axially movable rod projects out from a face side of the third transverse wall of the three-port two-position valve while a free end of the axially movable rod projects out from a rod side. The three-port two-position valve may be a spool design or a poppet design that can be replaced by a five-port, three-port or a two-port valve.
[0020] The counter balance chamber has an incoming connection and a mechanical energy accumulator. The hydraulic or pneumatic pressure coupled with accumulated energy of the mechanical energy accumulator applies a combination force on a moving surface of the counter balance chamber. The moving surface has a face I and a face II. One end of the pre-loaded compression spring is fixed axially to the face I of the moving surface and other end is fixed to a rigid side of the counterbalance chamber.
[0021] The first face of the axially movable rod projected out from the face side of the third transverse wall is connected axially with the face II of the moving surface of the counterbalance chamber. The free end projected out from the rod side of the three-port two-position valve is connected axially with the interacting end projected out from the first end of the common piston bar. The connection from a hydraulic or pneumatic supply to the three solenoid operated valves, the counter balance chamber and the three-port two-position valve may or may not be from a common source. At least two of the logic chamber, the three-port two-position valve and the counterbalance chamber are an integral device.
[0022] In the present embodiment, the hydraulic or pneumatic supply to the three solenoid operated valves, the counter balance chamber and the three-port two-position valve is from a common source. However, the source of such a supply may be more than one. The hydraulic or pneumatic supply is enabled to each of the pockets; through the first solenoid operated valve to the first pocket, through the second solenoid operated valve to the second pocket and through the third solenoid operated valve to the third pocket. The hydraulic or pneumatic supply is always available to the incoming connection of the counter balance chamber through a channel irrespective of the three solenoid operated valves being energized or de-energized.
[0023] When none of the solenoids of the first solenoid operated valve or the second solenoid operated valve or the third solenoid operated valve is energized, the hydraulic or pneumatic supply through the inlet ports is disabled to all the pockets and consequently also to the pressure sensors and or visual indicators. In this situation, the mechanical energy accumulator, which is a pre-loaded compression spring, pushes away the moving surface of the counter balance chamber with a Force Fm, aided with a force F4 due to hydraulic or pneumatic pressure constantly available from the hydraulic or pneumatic supply to the incoming connection of the counter balance chamber while there is no resistance to this force (Fm+F4) from the logic chamber side, thus the axially movable rod takes the position X and the first and the second transverse walls connect the exhaust port with the outlet port.
[0024] When one of the solenoids of the first solenoid operated valve or the second solenoid operated valve or the third solenoid operated valve is energized, the hydraulic or pneumatic supply is enabled to the corresponding pocket, also activating the corresponding pressure sensor and or visual indicator. In this situation, the resultant pneumatic force from the logic chamber side is less than or equal to the force of (Fm + F4) from the counter balance chamber side, thus the axially movable rod retains the position X and the first and the second transverse walls connect the exhaust port with the outlet port.
[0025] When at least two of first solenoid operated valve or the second solenoid operated valve or the third solenoid operated valve are energized, the hydraulic or pneumatic supply is enabled to the corresponding pockets also activating the corresponding pressure sensors and or visual indicators. In this situation, the resultant pneumatic force from the logic chamber side is significantly greater than the force of (Fm + F4) from the counter balance chamber side, thus the axially movable rod takes the position Y and the first and the second transverse walls connect the inlet port with the outlet port.
[0026] The present invention can be tailored for “1-out-of-2”, “2-out-of-2” and other redundant configurations with minimal modification.

BRIEF DESCRIPTION OF THE DRAWINGS
[0027] Figure 1 shows an assembly of a logic chamber and a counterbalance chamber with a two position switching device for deployment in “2-out-of-3” and other redundancy configurations.
[0028] Figure 1A shows a valve actuation arrangement with three solenoid operated valves in a disabled condition.
[0029] Figure 1B shows the valve actuation arrangement with three solenoid operated valves in an enabled condition.
[0030] Figure 2A shows a prior art arrangement with four solenoid operated valves for achieving “2-out-of-3” configuration.
[0031] Figure 2B is a truth table showing actuation status of solenoids and a resultant of the prior art arrangement of Figure 2A.
[0032] Figure 3A shows another prior art arrangement with three 5-port 2-way solenoid operated valves for achieving “2-out-of-3” configuration.
[0033] Figure 3B is a truth table illustrating actuation status of pressure sensors based on the various operating states of the solenoid operated valves of Figure 3A.
[0034] Figure 4A shows the solenoid arrangement similar to Figure 3A with one valve disposed in reverse configuration with reference to Figure 3A.
[0035] Figure 4B is a truth table illustrating the actuation status of the pressure sensors based on the various operating states of the solenoid operated valves of Figure 4A.
[0036] Figure 5A shows a logic chamber of the valve actuation arrangement.
[0037] Figure 5B shows a three-port two-position valve of the valve actuation arrangement.
[0038] Figure 5C shows a counterbalance chamber of the valve actuation arrangement.
[0039] Figure 6 shows an assembly of the logic chamber, the three-port two-position valve and the counterbalance chamber.
[0040] Figures 7-13 are schematic diagrams of the valve actuation arrangement showing various operating states when the solenoid operated valves are enabled or disabled for “2-out-of-3” configuration.
[0041] Figures 14-17 are schematic diagrams of the valve actuation arrangement showing various operating states when the solenoid operated valves are enabled or disabled for a “1-out-of-2” configuration.
[0042] Figures 18-21 are schematic diagrams of the valve actuation arrangement showing various operating states when the solenoid operated valves are enabled or disabled for a “2-out-of-2” configuration.

DETAILED DESCRIPTION
[0043] The invention shall now be described with the help of accompanying drawings. It is to be expressly noted that several variations are possible around the invention and the drawings and description should not be construed to limit the invention in any manner whatsoever.
[0044] The preferred embodiment of present invention described is an actuation arrangement for a “2-out-of-3” configuration. Subsequently, it is described to tailor the arrangement for “1-out-of-2”, “2-out-of-2” and such other redundant configurations.
[0045] Figure 1, a logic chamber (115) and a counter balance chamber (110) are disposed on either sides of a two position switching device (145) for deploying in an actuation arrangement (90) as “2-out-of-3” configuration or other redundant configurations.
[0046] Figures 1A and 1B, as per present invention, are embodiments of a valve actuation arrangement (100) with three enabling devices for the “2-out-of-3” configuration. While all illustrations and explanation here below is with solenoid operated valves (101-103) to represent three enabling devices particularly fluidic pressure enabling devices, however levers, push buttons, pressure operated valves or any enabling devices or particularly fluidic pressure enabling devices may be deployed. Thus, the valve actuation arrangement (100) as per present embodiment has a first solenoid operated valve (101), a second solenoid operated valve (102) and a third solenoid operated valve (103) for achieving a true “2-out-of-3” system. The valve actuation arrangement (100) in this embodiment comprises a three-port two-position valve (127), the logic chamber (115), and the counterbalance chamber (110) pneumatically or hydraulically interconnected with the three solenoid operated valves (101-103) as shown. Instead of the three-port two-position valve (127) any commensurate two-stage switching device can be deployed which needs to be switched with redundancy logic.
[0047] Figure 1A, none of the solenoid operated valves (101-103) are enabled while Figure 1B, all the three solenoid operated valves (101-103) are enabled. Before we understand the present invention, it is important to fully appreciate the current problem for the “2-out-of-3” configuration, which is described with the help of Figures 2A to 4B below.
[0048] Figure 2A, with four solenoid valves, wherein a solenoid valve V1 acts as a channel 1, solenoid valves V2 and V3 act as a channel 2 and a solenoid valve V4 acts as a channel 3. Figure 2B, a truth table shows two situations where two solenoid valves are ON, however the resultant is still OFF; in other words, two false conditions arise and “2-out-of-3” requirement is not met. For example, in condition exhibited by Sr. No. 5 (P1-5), wherein the solenoid valve V1 and the solenoid valve V3 are ON and the solenoid valve V2 and the solenoid valve V4 are OFF, referring back to Figure 2A, air flows from a main line 1-1 to the outlet 2 of V1, since V2 is OFF, air flow gets blocked at solenoid valve V2 and continues to flow through solenoid V3 from inlet 1 to outlet 2 and is blocked at solenoid valve V4 at inlet 1 and does not reach the line 2-2. Thus, the resultant (51) is OFF. Here, the “2-out-of-3” requirement is unfulfilled. Similarly, in condition exhibited by Sr. No. 8 (P1-8), wherein the solenoid valve V2 and the solenoid valve V4 are ON and V1 and V3 are OFF, referring back to Figure 2A, air flow is directed from main line 1-1 and gets blocked at inlet 1 of the solenoid valve V3, failing to reach the line 2-2. Thus, the resultant (51) is OFF and “2-out-of-3” requirement is unfulfilled again. To add pressure sensor and or visual indicator for sensing valve operation, additional components like shuttle valve et cetera needs to be added.
[0049] Figure 3A shows a voting solenoid arrangement (10) as another prior art arrangement with three 5-port 2-way solenoid operated valves (20, 22 and 24) having pressure switches or pressure sensors (40, 42 and 44) which alternatively open and or close in response to presence and or absence of pressure at corresponding solenoid operated valves (20, 22 and 24). An air supply (12) to the voting solenoid arrangement (10) through the conduit (16) which subsequently flows from the solenoid arrangement (10) to valve (14) through the conduit (18) noting that a passageway (26) represents air flow when the solenoid valves (20, 22 and 24) are in energized state and a passageway (27) represents air flow when the solenoid valves (20, 22 and 24) are in de-energized state.
[0050] Figure 3B shows a truth table, wherein E stands for energized state and D stands for de-energized state of a solenoid of the respective solenoid valves (20, 22 and 24). For Figures 3B as well as 4B, serial numbers abbreviated as Sr. No. are indicated in column (60) while resultant is shown in column (50).
[0051] For example, considering all the three solenoid valves (20, 22 and 24) are energized (condition at Sr. No.1 as indicated in Figure 3B), referring to Figure 3A, the air supply (12) through conduit (16) flows to port (201) of valve (20) and to the port (225) of the valve (22). Through the passageway (26) of the valve (20), air from the port (201) flows to the port (202) followed by the port (221) of the valve (22) through passageway (28) skipping activation of pressure sensor (40) (indicated as OFF in Figure 3B). Further from the port (221), air flows to the port (222) through passageway (26) of the solenoid valve (22). From the port (222), air travels through passageway (30) thus activating the pressure sensor (42) (indicated as ON in Figure 3B).
[0052] Further, air flows to the port (241) followed by port (242) through passageway (26) of the valve (24) thereby activating sensor (44) (indicated as ON in Figure 3B). The air supply (12) which was directed to the valve (22) through the conduit (16) flows to the port (225) through passageway (32). Further from port (225), air flows through the passageway (26) to the port (224) which is further directed to the port (245) of the valve (24) through passageway (34). Finally, from port (245), air flows to the port (244) through the passageway (26) and is received by the valve (52) through the conduit (18). Thus, the resultant is indicated as ON in the column (50) (condition at Sr. No.1) of Figure 3B. Therefore, the three solenoid valves (20,22 and 24) when in energized state, the resultant is ON satisfying “2-out-of-3” function but the pressure sensor (40) remains OFF and pressure sensors (42 and 44) are only ON, leading to a false indication.
[0053] In condition as per Sr. No. 2, wherein solenoid valve (20) is de-energized and solenoid valves (22 and 24) are energized (indicated accordingly in Figure 3B), referring back to Figure 3A, the air supply (12) through conduit (16) flows from the port (201) to the port (204) through passageway (27) of the valve (20), activating the pressure sensor (40) (indicated as ON in Figure 3B). Further through passageway (32), air flows from the port (225) to the port (224) through passageway (26). Further from port (224), air is directed to port (245) of the valve (24) followed by the port (244) through the passageway (26) finally to the valve (52) through the conduit (18) (the resultant in column (50) indicated as ON in Figure 3B) thus de-activating the pressure sensors (42 and 44) (indicated as OFF in the truth table of Figure 3B). The conditions at Sr. No. 3 and 4 of the truth table work on the similar lines as conditions at Sr. No. 1 and 2 explained above.
[0054] Looking at the condition at Sr. No. 5, wherein all the solenoid operated valves (20, 22 and 24) are de-energized, referring back Figure 3A, air flows through conduit (16) to the port (201) of the valve (20) following the port (204) through passageway (27) thus activating the pressure sensor (40) (indicated as ON in the truth table of Figure 3B) and the pressure sensors (42 and 44) remain OFF (indicated in the truth table of Figure 3B) as no air flows through the solenoid valves (22 and 24) in the de-energized state. The resultant is indicated as OFF (as seen in column (50), condition at Sr. No. 5) as no air flows to the valve (52) thus following the “2-out-of-3” function.
[0055] Considering condition as per Sr. No. 6, wherein valve (20) is energized and valves (22 and 24) are de-energized, referring back to Figure 3A, the air supply (12) through conduit (16) is directed to the port (201) of valve (20). Further from port (201), air flows to the port (202) through the passageway (26) skipping the activation of pressure sensor (40) (indicated as OFF in Figure 3B). From the port (202), air flows to the port (221) of the valve (22) through the passageway (28). Further, air flows to the port (224) through the passageway (27) and is directed to the port (245) of the valve (24) where the flow gets blocked as the valve (24) is de-energized, thus the resultant is OFF (as seen in column (50), condition as per Sr. No. 6) and the pressure sensors (42 and 44) remain de-activated (indicated as OFF in Figure 3B). The conditions as per Sr. No.7 and 8 work on similar lines as that of the conditions for Sr. No. 5 and 6 explained above. Thus, looking at the actuation status of the sensors (40, 42 and 44), it is observed that even though three number 5-port 2-way valve follows “2-out-of-3” function but the pressure sensors (40, 42 and 44) do not follow any particular logic and the user gets misleading pressure sensor outputs.
[0056] Figure 4A shows the solenoid arrangement (10’) similar to the solenoid arrangement (10) of Figure 3A except the valve (24’) which is disposed in a reverse configuration as related to valve (24) of Figure 3A. Figure 4B is a truth table illustrating the actuation of the pressure switches or pressure sensors (40, 42 and 44) based on the operating states of the solenoid operated valves (20, 22 and 24’). Considering all the three solenoid valves (20, 22 and 24’) in energized state (as indicated in the condition as per Sr. No. 1 of the truth table of Figure 4B), the air supply (12) through conduit (16) flows from the port (201) to the port (202) through the passageway (26) skipping the activation of pressure sensor (40) (indicated as OFF in the truth table of Figure 4B).
[0057] Further, from the port (202), air is directed to the port (221) of solenoid valve (22) through passageway (28) following the port (222) through passageway (26) further travelling through passageway (30) activating the pressure sensor (42) (indicated as ON in Figure 4B) and then travelling to the port (244) of the valve (24’) and stopping at the plug (245) thus pressure sensor (44) remain de-activated, indicated as OFF (condition as per Sr. No. 1) in Figure 4B. In addition, air supply (12) through passageway (32) is given to the port (225) of the second solenoid valve (22) which further flows to the port (224) through the passageway (26) that is directed to the port (242) of the valve (24’) further connecting the port (241) to the valve (52) through conduit (18). Thus the resultant is ON as indicated in the column (50) (condition as per Sr. No. 1) of Figure 4B.
[0058] Considering condition as per Sr. No. 2 of Figure 4B, wherein solenoid valve (20) is de-energized and the solenoid valves (22 and 24’) are energized, referring back to the Figure 4A, the air supply (12) through the conduit (16) flows to the port (201) of valve (20). Further from port (201), air is directed to port (204) through passageway (27) thus activating the pressure sensor (40) (indicated as ON in the Truth table of Figure 4B). The air flow from conduit (16) gets divided and through passageway (32) reaches the port (225) which further travels to port (224) through passageway (26). From port (224), air is directed to the port (242) of the valve (24’) further to the port (241) through passageway (26) and finally to the valve (52) through conduit (18) thus the resultant (as seen in column (50)) (condition as per Sr. No. 2) obtained is ON satisfying the “2-out-of-3” function. In this case, the pressure sensors (42 and 44) remain de-activated (indicated as OFF in Figure 4B). The conditions as per Sr. No. 3 and 4 work on the similar lines as that of conditions as per Sr. No. 1 and 2 explained above.
[0059] Further, considering condition as per Sr. No. 6 of the truth table of Figure 4B wherein the solenoid valve (20) is energized and the solenoid valves (22 and 24’) are de-energized, referring back to the Figure 4A, air flows from supply (12) to port (201) of the solenoid valve (20). From the port (201), air is directed to the port (202) through passageway (26) maintaining the pressure sensor (40) in deactivated state (indicated as OFF in Figure 4B). The flow from the port (202) is directed to the port (221) of the valve (22) through passageway (28). Further from the port (221), air is directed to the port (224) through the dotted passageway (27), thus skipping the activation of pressure sensor (42) (indicated as OFF in the Figure 4B). Further from the port (224), air is directed to the port (242) of the valve (24’). From the port (242), air flows to the port (243) of the valve (24’) activating the sensor (44) (indicated as ON in the Figure 4B). The resultant is this case is OFF (as seen in column (50), condition as per Sr. No. 6) as there is no air supply received at the valve (52). Thus, satisfying the “2-out-of-3” function. The conditions as per Sr. No. 5 and Sr. Nos. 7-8 function on the same principle as the working of the condition as per Sr. No. 6 explained above.
[0060] As seen from the truth table, even though the solenoid valves (20, 22 and 24’) follows “2-out-of-3” configuration by providing resultant ON (in column (50)) when at least two valves out of (20, 22 and 24’) are energized, but pressure sensors (40, 42 and 44) do not follow any particular pattern and thus it becomes difficult for the user to relate the operating state of the solenoid operated valves (20, 22 and 24’) with the pressure sensors (40, 42 and 44).
[0061] The description here onwards focuses on present invention.
[0062] Figure 5A, the logic chamber (115) has at least four co-axial cylindrical chambers (116-119). The embodiment considers cylindrical chambers (116-119) but they could be of any cross section. A first chamber (116) has a diameter larger than a second chamber (117), the second chamber (117) has a diameter larger than a third chamber (118) and the third chamber (118) has a diameter larger than a fourth chamber (119). The first chamber (116) has a first inlet port (123), the second chamber (117) has a second inlet port (124) and the third chamber (118) has a third inlet port (125). Each of these cylindrical chambers (116-119) may have an exhaust port, not shown. The first chamber (116) has a first piston (107), the second chamber (117) has a second piston (106), the third chamber (118) has a third piston (105) and the fourth chamber (119) has a fourth piston (104). The first piston (107) has a face I (107a) and a face II (107b), the second piston (106) has a face I (106a) and a face II (106b), a third piston (105) has a face I (105a) and a face II (105b), and likewise the fourth piston (104) has a face I (104a) and a face II (104b).
[0063] The face II (107b) of the first piston (107) and the face I (106a) of the second piston (106) form parts of a first pocket (120), the face II (106b) of the second piston (106) and the face I (105a) of the third piston (105) form parts of a second pocket (121), the face II (105b) of the third piston (105) and the face I (104a) of the fourth piston (104) form parts of a third pocket (122). A last pocket (122L) is formed between an end wall (99) of the logic chamber (115) and the face II (104b) of the fourth piston (104b). The first pocket (120) comprises partly of the first chamber (116) and partly of the second chamber (117). The second pocket (121) comprises partly of the second chamber (117) and partly of the third chamber (118). Likewise, the third pocket (122) comprises partly of the third chamber (118) and partly of the fourth chamber (119). The last pocket (122L) comprises only of a last chamber. The pressure sensors and or visual indicators (139,140 and 141) are connected to the first pocket (120), the second pocket (121) and the third pocket (122) respectively. These pressure sensors and or visual indicators (139,140 and 141) indicate the operating state of the solenoid operated valves (101-103) when energized or de-energized.
[0064] The first piston (107), the second piston (106), the third piston (105) and the fourth piston (104) are disposed on a common piston bar (114). The common piston bar (114) has an interacting end (131) extending from a first end (132) of the logic chamber (115).
[0065] Figure 5B, the three-port two-position valve (127) has an inlet port (111), an outlet port (113) and an exhaust port (112). An axially movable rod (130) has at least a first transverse wall (128), a second transverse wall (129) and a third transverse wall (137), two transverse walls (128 and 129) are located such that when the axially movable rod (130) is in a position X, the transverse walls (128 and 129) connect the outlet port (113) with the exhaust port (112) as can also be seen in Figure 1A; and when the axially movable rod (130) is a position Y then the transverse walls (128 and 129) connect the inlet port (111) with the outlet port (113) as can be seen in Figure 1B. A first face (138) of the axially movable rod (130) projects out from a face side (137a) of third transverse wall (137) of the three-port two-position valve (127) while a free end (134) of the axially movable rod (130) projects out from a rod side (133). The figures show three-port two-position valve (127) as a spool design, however a poppet design may also be used.
[0066] Figure 5C, the counter balance chamber (110) has an incoming connection (126) and a mechanical energy accumulator. The incoming connection (126) coupled with accumulated energy of the mechanical energy accumulator which is a pre-loaded compression spring (109), apply a combination force (Fm+F4) on a moving surface (108) having a face I (108a) and a face II (108b). One end of the pre-loaded compression spring (109) is fixed axially to the face I (108a) of the moving surface (108) and other end of the pre-loaded compression spring (109) is fixed to a rigid side (143) of the counterbalance chamber (110).
[0067] Figure 6 seen with Figures 5A and 5B, the three-port two-position valve (127) having the first face (138) of the axially movable rod (130) interacts with the face II (108b) of the moving surface (108) of the counter balance chamber (110) as indicated by dotted circle (1); the free end (134) of the axially movable rod (130) is connected axially with the interacting end (131) of the common piston bar (114) as indicated by dotted circle (2).
[0068] In the present embodiment, a hydraulic or pneumatic supply (142) to the three solenoid operated valves (101-103), the counter balance chamber (110) and the three-port two-position valve (127) is from a common source. However, the source of such a supply (142) may be more than one. The hydraulic or pneumatic supply (142) is enabled to each of the pockets (120-122); through the first solenoid operated valve (101) to the first pocket (120), through the second solenoid operated valve (102) to the second pocket (121) and through the third solenoid operated valve (103) to the third pocket (122). The hydraulic or pneumatic supply (142) is always available to the incoming connection (126) of the counter balance chamber (110) through a channel (135) irrespective of the three solenoid valves (101-103) being energized or de-energized.
[0069] When none of the solenoids of the first solenoid operated valve (101) or the second solenoid operated valve (102) or the third solenoid operated valve (103) is energized, the hydraulic or pneumatic supply (142) through inlet ports (123-125) is disabled to all the pockets (120-122) respectively and consequently also to the pressure sensors and or visual indicators (139-141). In this situation, the mechanical energy accumulator, which is a pre-loaded compression spring (109), pushes away the moving surface (108) of the counter balance chamber (110) with the Force Fm, aided with a force F4 due to a hydraulic or pneumatic pressure constantly available from the hydraulic or pneumatic supply (142) to the incoming connection (126) of the counter balance chamber (110); while there is no resistance to this combination force (Fm+F4) from the logic chamber (115) side. Thus, the axially movable rod (130) takes the position X and the first and the second transverse walls (128 and 129) connect the exhaust port (112) with the outlet port (113).
[0070] When one of the solenoids of first solenoid operated valve (101) or the second solenoid operated valve (102) or the third solenoid operated valve (103) is energized, the hydraulic or pneumatic supply (142) is enabled to the corresponding pocket (120 or 121 or 122), also activating the corresponding pressure sensor and or visual indicator (139 or 140 or 141). In this situation, the resultant pneumatic force from the logic chamber (115) side is less than or equal to the force (Fm + F4) from the counter balance chamber (110) side, thus the axially movable rod (130) retains the position X and the first and the second transverse walls (128 and 129) connect the exhaust port (112) with the outlet port (113).
[0071] When at least two or all the three solenoids of first solenoid operated valve (101) and or the second solenoid operated valve (102) and or the third solenoid operated valve (103) are energized, the hydraulic or pneumatic supply (142) is enabled to the corresponding pockets (120 and or 121 and or 122) also activating the corresponding pressure sensors and or visual indicators (139 and or 140 and or 141). In this situation, the resultant pneumatic force from the logic chamber (115) side is significantly greater than the combination force (Fm + F4) from the counter balance chamber (110) side, thus the axially movable rod (130) takes the position Y and the first and the second transverse walls (128 and 129) connect the inlet port (111) with the outlet port (113).
[0072] There are several dimensional variations by which such function as described above is achieved.
[0073] In a preferred embodiment,

Area of the moving surface (108) of the counterbalance chamber (110) = A
Area of the fourth piston (104) = A
Area of the third piston (105) = Ax2
Area of the second piston (106) = Ax3
Area of the first piston (107) = Ax4
Force of compression spring = Fm
Hydraulic or pneumatic pressure = p
pA > Fm > frictional force of the actuation arrangement (90)
F1 = Ax4xp
F2=Ax3xp
F3=Ax2xp
F4=Axp
Value of p is >= 2 bar, while value of A is fixed such as to achieve operation as described above and also quantitatively explained below.
[0074] Figure 7, when the solenoid of the first solenoid operated valve (101) is energized, the hydraulic or pneumatic supply (142) is enabled at a pressure “p” to the first pocket (120) through the first inlet port (123) thus activating the pressure sensor and or visual indicator (139). In this situation, the mechanical energy accumulator, which is a pre-loaded compression spring (109), pushes the moving surface (108) of the counter balance chamber (110) with the Force Fm, aided with the force F4 due to hydraulic or pneumatic pressure constantly available from the hydraulic or pneumatic supply (142) to the incoming connection (126) of the counter balance chamber (110). Consequent to the pressure “p” in the first pocket (120), there is a force p x 4 x A on the face II (107b) of the first piston (107) opposing the force Fm while there is a force p x A x 3 on the face I (106a) of the second piston (106) augmenting the force Fm.
[0075] Resultantly, there is a net force Fm, derived by [Fm + p x A - p x A(4-3)] in the direction shown, thus the axially movable rod (130) takes or retains the position X and the first and the second transverse walls (128 and 129) connect the exhaust port (112) with the outlet port (113).
[0076] Figure 8, when the solenoid of the second solenoid operated valve (102) is energized, the hydraulic or pneumatic supply (142) is enabled at a pressure “p” to the second pocket (121) thus also activating the pressure sensor (140). In this situation, the pre-loaded compression spring (109) pushes the moving surface (108) of the counter balance chamber (110) with the Force Fm, aided with the force F4 due to hydraulic or pneumatic pressure constantly available from the hydraulic or pneumatic supply (142) to the incoming connection (126) of the counter balance chamber (110). Consequent to the pressure “p” in the second pocket (121), there is a force p x A x 3 on the face II (106b) of the second piston (106) opposing the force Fm while there is a force p x A x 2 on the face I (105a) of the third piston (105) augmenting the force Fm. Resultantly, there is a net force Fm, derived by [Fm + p x A - p x A(3-2)] in the direction shown, thus the axially movable rod (130) retains the position X and the first and the second transverse walls (128 and 129) connect the exhaust port (112) with the outlet port (113).
[0077] Figure 9, when the solenoid of the third solenoid operated valve (103) is energized, the hydraulic or pneumatic supply (142) is enabled at a pressure “p” to the third pocket (122) thus also activating the pressure sensor and or visual indicator (141). In this situation, the pre-loaded compression spring (109) pushes the moving surface (108) of the counter balance chamber (110) with the Force Fm, aided with the force F4 due to hydraulic or pneumatic pressure constantly available from the hydraulic or pneumatic supply (142) to the incoming connection (126) of the counter balance chamber (110). Consequent to the pressure “p” in the third pocket (122), there is a force p x A x 2 on the face II (105b) of the third piston (105) opposing the force Fm while there is a force p x A on the face I (104a) of the fourth piston (104) augmenting the force Fm. Resultantly, there is a net force Fm, derived by [Fm + p x A - p x A(2-1)] in the direction shown, thus the axially movable rod (130) retains the position X and the first and the second transverse walls (128 and 129) connect the exhaust port (112) with the outlet port (113).
[0078] Figure 10, when the solenoids of the first solenoid operated valve (101) and the second solenoid operated valve (102) are energized, the hydraulic or pneumatic supply (142) is enabled at a pressure “p” to the first pocket (120) and the second pocket (121) thus also activating the pressure sensors and or visual indicators (139 and 140) respectively. In this situation, the pre-loaded compression spring (109) pushes the moving surface (108) of the counter balance chamber (110) with the Force Fm, aided with the force F4 due to hydraulic or pneumatic pressure constantly available from the hydraulic or pneumatic supply (142) to the incoming connection (126) of the counter balance chamber (110). Consequent to the pressure “p” in the first pocket (120) and the second pocket (121), there is a force p x A x 4 on the face II (107b) of the first piston (107) opposing the force Fm while there is a force p x A x 3 on the face I (106a) of the second piston (106) augmenting the force Fm. Further, there is a force p x A x 3 on the face II (106b) of the second piston (106) opposing the force Fm while there is a force p x A x 2 on the face I (105a) of the third piston (105) augmenting the force Fm. Resultantly, there is a net force Fm - p x A, derived by [Fm + p x A – p x A x (4+3-3-2)]. Since Fm < pA, the net resultant force is in the direction shown, thus the axially movable rod (130) takes the position Y and the first and the second transverse walls (128 and 129) connect the inlet port (111) with the outlet port (113).
[0079] Figure 11, when the solenoids of the first solenoid operated valve (101) and the third solenoid operated valve (103) are energized, the hydraulic or pneumatic supply (142) is enabled at a pressure “p” to the first pocket (120) and the third pocket (122) thus activating the pressure sensors and or visual indicators (139 and 141) respectively. In this situation, the pre-loaded compression spring (109) pushes the moving surface (108) of the counter balance chamber (110) with the Force Fm, aided with the force F4 due to hydraulic or pneumatic pressure constantly available from the hydraulic or pneumatic supply (142) to the incoming connection (126) of the counter balance chamber (110). Consequent to the pressure “p” in the first pocket (120) and the third pocket (122), there is a force p x A x 4 on the face II (107b) of the first piston (107) opposing the force Fm while there is a force p x A x 3 on the face I (106a) of the second piston (106) augmenting the force Fm. Further, there is a force p x A x 2 on the face II (105b) of the third piston (105) opposing the force Fm while there is a force p x A on the face I (104a) of the fourth piston (104) augmenting the force Fm. Resultantly, there is a net force Fm - p x A, derived by [Fm + p x A – p x A x (4-3+2-1)]. Since Fm < pA, the net resultant force is in the direction shown, thus the axially movable rod (130) takes the position Y and the first and the second transverse walls (128 and 129) connect the input port (111) with the outlet port (113).
[0080] Figure 12, when the solenoids of the second solenoid operated valve (102) and the third solenoid operated valve (103) are energized, the hydraulic or pneumatic supply (142) is enabled at a pressure “p” to the second pocket (121) and the third pocket (122) thus activating the pressure sensors and or visual indicators (140 and 141) respectively. In this situation, the pre-loaded compression spring (109) pushes the moving surface (108) of the counter balance chamber (110) with the Force Fm, aided with the force F4 due to hydraulic or pneumatic pressure constantly available from the hydraulic or pneumatic supply (142) to the incoming connection (126) of the counter balance chamber (110). Consequent to the pressure “p” in the second pocket (121) and the third pocket (122), there is a force p x A x 3 on the face II (106b) of the second piston (106) opposing the force Fm while there is a force p x A x 2 on the face I (105a) of the third piston (105) augmenting the force Fm. Further, there is a force p x A x 2 on the face II (105b) of the third piston (105) opposing the force Fm while there is a force p x A on the face I (104a) of the fourth piston (104) augmenting the force Fm. Resultantly, there is a net force (Fm - p x A), derived by [Fm + p x A – p x A x (3-2+2-1)]. Since Fm < pA, the net resultant force is in the direction shown, thus the axially movable rod (130) takes the position Y and the transverse walls (128 and 129) connect the inlet port (111) with the outlet port (113).
[0081] Figure 13, when the solenoids of the first solenoid operated valve (101), the second solenoid operated valve (102) and the third solenoid operated valve (103) are energized, the hydraulic or pneumatic supply (142) is enabled at a pressure “p” to the first pocket (120), the second pocket (121) and the third pocket (122) thus activating the pressure sensors and or visual indicators (139, 140 and 141) respectively. In this situation, the pre-loaded compression spring (109) pushes the moving surface (108) of the counter balance chamber (110) with the Force Fm, aided with the force F4 due to hydraulic or pneumatic pressure constantly available from the hydraulic or pneumatic supply (142) to the incoming connection (126) of the counter balance chamber (110). Consequent to the pressure “p” in the first pocket (120), the second pocket (121) and the third pocket (122), there is a force p x A x 4 on the face II (107b) of the first piston (107) opposing the force Fm while there is a force p x A x 3 on the face I (106a) of the second piston (106) augmenting the force Fm. Further, there is a force p x A x 3 on the face II (106b) of the second piston (106) opposing the force Fm while there is a force p x A x 2 on the face I (105a) of the third piston (105) augmenting the force Fm. Still further, there is a force p x A x 2 on face II (105b) of the third piston (105) opposing the force Fm while there is a force p x A on the face I (104a) of the fourth piston (104) augmenting the force Fm. Resultantly, there is a net force (Fm – 2 x p x A), derived by [Fm + p x A – p x A x (4-3+3-2+2-1)]. Since Fm < pA, the net resultant force is in the direction shown, thus the axially movable rod (130) takes the position Y and the first and the second transverse walls (128 and 129) connect the input port (111) with the outlet port (113).
[0082] By dimensional and force variations in the actuation arrangement (90), different redundant configurations can be catered to by the present invention.
[0083] Another redundant configuration commonly known as “1-out-of-2” has two enabling devices and requires that the two position switching device (145) takes the first position towards the counterbalance chamber (110) only when both enabling devices are energized. This embodiment is easily derivable from above comprehensively described “2-out-of-3” configuration, in two alternative manners. As a first alternative, the two enabling devices are associated to any two of the three inlet ports (123-125). As a second alternative (100a), shown in Figure 14, a logic chamber (115a) with two pockets – the first pocket (120) and the second pocket (121) is deployed.
[0084] Figure 15 as seen with Figure 14, when the solenoid of the first solenoid operated valve (101) is energized, the hydraulic or pneumatic supply (142) is enabled at a pressure “p” to the first pocket (120) through the first inlet port (123) thus activating the pressure sensor and or visual indicator (139). In this situation, the pre-loaded compression spring (109), pushes the moving surface (108) of the counter balance chamber (110) with the Force Fm, aided with the force F4 due to hydraulic or pneumatic pressure constantly available from the hydraulic or pneumatic supply (142) to the incoming connection (126) of the counter balance chamber (110). Consequent to the pressure “p” in the first pocket (120), there is a force p x 4 x A on the face II (107b) of the first piston (107) opposing the force Fm while there is a force p x A x 3 on the face I (106a) of the second piston (106) augmenting the force Fm.
[0085] Resultantly, there is a net force Fm, derived by [Fm + p x A - p x A x (4-3)] in the direction shown, thus the axially movable rod (130) takes the position X and the first and the second transverse walls (128 and 129) connect the exhaust port (112) with the outlet port (113).
[0086] Figure 16 as seen with Figure 14, when the solenoid of the second solenoid operated valve (102) is energized, the hydraulic or pneumatic supply (142) is enabled at a pressure “p” to the second pocket (121) thus also activating the pressure sensor or visual indicator (140). In this situation, the pre-loaded compression spring (109) pushes the moving surface (108) of the counter balance chamber (110) with the Force Fm, aided with the force F4 due to hydraulic or pneumatic pressure constantly available from the hydraulic or pneumatic supply (142) to the incoming connection (126) of the counter balance chamber (110). Consequent to the pressure “p” in the second pocket (121), there is a force p x A x 3 on the face II (106b) of the second piston (106) opposing the force Fm while there is a force p x A x 2 on the face I (105a) of the third piston (105) augmenting the force Fm.
[0087] Resultantly, there is a net force Fm, derived by [Fm + p x A - p x A (3-2)] in the direction shown, thus the axially movable rod (130) takes the position X and the first and the second transverse walls (128 and 129) connect the exhaust port (112) with the outlet port (113).
[0088] Figure 17 as seen with Figure 14, when the solenoids of the first solenoid operated valve (101) and the second solenoid operated valve (102) are energized, the hydraulic or pneumatic supply (142) is enabled at a pressure “p” to the first pocket (120) and the second pocket (121) thus also activating the pressure sensors and or visual indicators (139 and 140) respectively. In this situation, the pre-loaded compression spring (109) pushes the moving surface (108) of the counter balance chamber (110) with the Force Fm, aided with the force F4 due to hydraulic or pneumatic pressure constantly available from the hydraulic or pneumatic supply (142) to the incoming connection (126) of the counter balance chamber (110). Consequent to the pressure “p” in the first pocket (120) and the second pocket (121), there is a force p x A x 4 on the face II (107b) of the first piston (107) opposing the force Fm while there is a force p x A x 3 on the face I (106a) of the second piston (106) augmenting the force Fm. Further, there is a force p x A x 3 on the face II (106b) of the second piston (106) opposing the force Fm while there is a force p x A x 2 on the face I (105a) of the third piston (105) augmenting the force Fm.
[0089] Resultantly, there is a net force Fm-p x A, derived by [Fm + p x A – p x A x (4-3+3-2)] in the direction shown, thus the axially movable rod (130) takes the position Y and the first and the second transverse walls (128 and 129) connect the inlet port (111) with the outlet port (113).
[0090] Yet another redundant configuration “2-out-of-2” also has two enabling devices but requires that the two position switching device (145) takes the first position towards the counterbalance chamber (110) when any one or both enabling devices are energized.
[0091] Figure 18, the valve actuation arrangement (100b), the logic chamber (115b) for this embodiment has two pistons, the first piston (107) and the third piston (105). The face II (107b) of the first piston (107) and the face I (105a) of the third piston (105) form parts of a first pocket (120). The last pocket (122L) is formed between the face II (105b) of the third piston (105) and the end wall (99). When neither of the solenoids of the first solenoid operated valve (101) or the third solenoid operated valve (103) is energized, the hydraulic or pneumatic supply (142) through inlet ports (123 and 125L) is disabled to both the pockets (120 and 122L) and consequently also to the pressure sensors and or visual indicators (139 and 141). In this situation, the mechanical energy accumulator, which is a pre-loaded compression spring (109), pushes away the moving surface (108) of the counter balance chamber (110) with the Force Fm, aided with the force F4 due to a hydraulic or pneumatic pressure constantly available from the hydraulic or pneumatic supply (142) to the incoming connection (126) of the counter balance chamber (110); while there is no resistance to this combination force (Fm+F4) from the logic chamber (115b) side. Thus, the axially movable rod (130) takes the position X and the first and the second transverse walls (128 and 129) connect the exhaust port (112) with the outlet port (113).
[0092] Figure 19 seen with Figure 18, when the solenoid of the first solenoid operated valve (101) is energized, the hydraulic or pneumatic supply (142) is enabled at a pressure “p” to the first pocket (120) through the first inlet port (123) thus activating the pressure sensor and or visual indicator (139). In this situation, the mechanical energy accumulator, which is the pre-loaded compression spring (109), pushes the moving surface (108) of the counter balance chamber (110) with the Force Fm, aided with the force F4 due to hydraulic or pneumatic pressure constantly available from the hydraulic or pneumatic supply (142) to the incoming connection (126) of the counter balance chamber (110). Consequent to the pressure “p” in the first pocket (120), there is a force p x 4 x A on the face II (107b) of the first piston (107) opposing the force Fm while there is a force p x A x 2 on the face I (105a) of the third piston (105) augmenting the force Fm.
[0093] Resultantly, there is a net force Fm- p x A, derived by [Fm + p x A - p x A(4-2)] in the direction shown, thus the axially movable rod (130) takes the position Y and the first and the second transverse walls (128 and 129) connect the inlet port (112) with the outlet port (113).
[0094] Figure 20 seen with Figure 18, when the solenoid of the third solenoid operated valve (103) is energized, the hydraulic or pneumatic supply (142) is enabled at a pressure “p” to the last pocket (122L) through a last inlet port (125L) thus also activating the pressure sensor and or visual indicator (141). In this situation, the pre-loaded compression spring (109) pushes the moving surface (108) of the counter balance chamber (110) with the Force Fm, aided with the force F4 due to hydraulic or pneumatic pressure constantly available from the hydraulic or pneumatic supply (142) to the incoming connection (126) of the counter balance chamber (110). Consequent to the pressure “p” in the last pocket (122L), there is a force p x A x 2 on the face II (105b) of the third piston (105) opposing the force Fm.
[0095] Resultantly, there is a net force Fm- p x A derived by [Fm + p x A - p x A x 2] in the direction shown, thus the axially movable rod (130) takes the position Y and the first and the second transverse walls (128 and 129) connect the inlet port (111) with the outlet port (113).
[0096] Figure 21 seen with Figure 18, when the solenoids of the first solenoid operated valve (101) and the third solenoid operated valve (103) are energized, the hydraulic or pneumatic supply (142) is enabled at a pressure “p” to the first pocket (120) and the last pocket (122L) thus also activating the pressure sensors and or visual indicators (139 and 141) respectively. In this situation, the pre-loaded compression spring (109) pushes the moving surface (108) of the counter balance chamber (110) with the Force Fm, aided with the force F4 due to hydraulic or pneumatic pressure constantly available from the hydraulic or pneumatic supply (142) to the incoming connection (126) of the counter balance chamber (110). Consequent to the pressure “p” in the first pocket (120) and the last pocket (122L), there is a force p x A x 4 on the face II (107b) of the first piston (107) opposing the force Fm while there is a force p x A x 2 on the face I (105a) of the third piston (105) augmenting the force Fm. Further, there is a force p x A x 2 on the face II (105b) of the third piston (105) opposing the force Fm.
[0097] Resultantly, there is a net force Fm- p x A x 3, derived by [Fm + p x A – p x A x (4+2-2)] in the direction shown, thus the axially movable rod (130) takes the position Y and the first and the second transverse walls (128 and 129) connect the inlet port (111) with the outlet port (113).
[0098] The activation of corresponding pressure sensors and or visual indicators (139- 141) upon the energizing or de-energizing of the solenoid operated valves (101-103) indicate the operating states of the three solenoid operated valves (101-103). The indication may be a visual signal using which a user can easily interpret functioning of the solenoid operated valves (101-103). As discussed in the prior art Figures 3A-4B, wherein the pressure sensors (40, 42 and 44) did not follow any particular logic and it would become difficult for the user to interpret the operating state of the solenoid operated valves, the present invention removes this loophole by presenting the exact operating state of the solenoid operated valves (101-103) in the form of visual signal.
[0099] Present embodiment is described with a typical construction and force proportions in apposition. Several force proportions and constructional variations are possible and this embodiment does not limit the possibilities in any way.
[0100] Present embodiments are described with three-port two-position valve (127), however, one can use this invention for 2 port, 5 port three or two position valve or any other commensurate two position switching device needed to be operated with desired redundancy configuration having been satisfied. Such commensurate two position switching device could also be an electrical or an electromechanical device, operated by using the output of the valve which could be fluidic, as described in above embodiment or mechanical, for example a linear or a rotary motion.
[0101] Thus, the commensurate two position switching device (145) has means to connect to the logic chamber (115 or 115a or 115b) on one end and to the counterbalance chamber (110) on the other end such that the two position switching device (145) takes either a first position towards the counterbalance chamber (110) and a second position towards the logic chamber (115, 115a, 115b) depending on the direction of a resultant force Fr as shown in Figure 6.
[0102] The logic chamber (115 or 115a or 115b), the three-port two-position valve (127) and the counterbalance chamber (110) are described as three discrete devices, however any two of them or all three of them can be an integral device.