DESC:FIELD OF THE INVENTION:
The present invention relates to a mechanism for sensing and regulating pressure in a discharge line. More particularly, the present invention relates to a mechanism for sensing and regulating pressure in a discharge line of a pneumatic device and or hydraulic device.

BACKGROUND OF THE INVENTION:

Generally, pressure sensing and regulation in a delivery line of a device delivering pressurized fluid is an important operation to carry out related operations with the device. The device can be a pneumatic device or a hydraulic device. The pneumatic device is an air compressor or an air pump or a blower and the like. The hydraulic device is a hydraulic pump or a fluid thruster and the like. These pneumatic and hydraulic devices delivers pressurized fluid by using mechanical energy through the delivery line. Sensing and regulating the pressure of the fluid in the delivery line is very important operation for operating other devices connected with these pneumatic and hydraulic devices for carrying out related operations.

For example, an air treatment and control unit is a unit connected with a pneumatic braking system of a vehicle. Generally, the air treatment and controlling unit is connected with an air compressor. The air treatment and controlling unit supplies moisture less pressurized air to the pneumatic braking system. Presently, a governor valve is used in the air treatment and controlling unit to control system pressure at a specific limit.

When pressure of the delivered air from a delivery line of the air treatment and controlling unit exceeds a predefined limit of pressure, the governor valve sends a pneumatic signal to a pressure control line connected with the air treatment and controlling unit for reducing air pressure released therefrom. A condition in which, the pressure of the delivered air from the delivery line of the air treatment unit is more than the predefined limit of the pressure is commonly known as “Cut- out” condition.

When pressure of the delivered air from the delivery line of the air treatment and controlling unit falls within the predefined limit of pressure, the governor valve maintains the pressure level in the delivery line of the air treatment and controlling unit. A condition in which, the pressure of the delivered air from the delivery line of the air treatment unit is below the predefined limit of pressure is commonly known as “Cut- in” condition.

Presently, existing governor valves includes diaphragms and piston rings. But, the construction of the existing governor valves is complex. Further, repeatability and reliability of the existing governor valves is less. Furthermore, due to exposure of the functional elements of the governor valve to fluctuated pressures of the delivered air from the air treatment and controlling unit causes wear and tear of the functional elements, thereby reducing operation life of the existing governor valves.

Hence there is a requirement of a mechanism, which overcomes from above mentioned problems.
OBJECT OF THE INVENTION:

Object of the present invention is to provide a mechanism for sensing and regulating pressure in a discharge line of a pneumatic or a hydraulic device.

Another object of the present invention is to provide a mechanism adopted to a governor valve connected with a pneumatic device for sensing and regulating pressure in a discharge line of a pneumatic device having more repeatability and reliability compared to existing governor valves.

Further object of the present invention is to provide a mechanism for sensing and regulating pressure in a discharge line, which is simple in construction.

Further one more object of the present invention is to provide a mechanism for sensing and regulating pressure in a discharge line, which is easily serviceable.

One more object of the present invention is to provide a mechanism for sensing and regulating pressure in a discharge line which is economical in operation.

SUMMARY OF THE INVENTION:
According to the present invention there is a mechanism for sensing and regulating pressure in a discharge line. The discharge line is a delivery line of a pneumatic or a hydraulic device. Pressurized fluid is delivered from the pneumatic or the hydraulic device through the discharge line. The mechanism includes a first piston, a second piston, piston seals and a flexible seal. The first piston moves upwards when an input pressure of fluid received from the discharge line of the pneumatic or the hydraulic device is more than a predefined pressure. In the present embodiment, the first piston is connected with a compression spring for exerting spring force on the first piston for defining a pressure limit.
In an alternative embodiment, the first piston can be connected with a weight or a pneumatic pressure capable to apply force on the first piston for defining the pressure limit which may be obvious to person ordinarily skilled in the art. The second piston is arranged within the first piston for opening and closing a pneumatic control line connected with the pneumatic or the hydraulic device. In the present embodiment, the pneumatic device is an air treatment and controlling unit. The air treatment and controlling unit is connected with a pneumatic braking system of a vehicle. The air treatment and controlling unit is connected with an air compressor. The air treatment and controlling unit supplies pressurized moisture less air to the pneumatic braking system of the vehicle.
In present embodiment, the first piston is connected to the second piston through a plunger spring connected there between for providing retention force to the second piston, when the second piston closes the pneumatic or hydraulic control line. In an alternative embodiment, the first piston is connected to the second piston without the plunger spring there between.
A passage is configured through the first piston and the second piston for releasing the received fluid from the discharge line of the pneumatic or the hydraulic device to the atmosphere (tank in case of hydraulic device) when the input pressure of the fluid is less than the predefined pressure. The passage includes a port configured in the second piston for receiving air. The flexible seal is arranged on the second piston opens the passage when the pressure is below the predefined pressure for maintaining the pressure level in the pneumatic or the hydraulic device. The flexible seal closes the passage when the first piston moves upward for passing fluid to the pneumatic control line as a signal, thereby regulates the discharge pressure from the pneumatic or hydraulic device. The flexible seal opens and closes the port upon (due) movements of the first and second piston caused by the pressurized fluid acting on the first piston.
In an alternative embodiment, the second piston and the first piston are integral. Further, the flexible seal is arranged on the first piston. The flexible seal opens and closes the pneumatic control line due to variations in the received pressure from the delivery line of the pneumatic or hydraulic device.
BRIEF DESCRIPTION OF THE DRAWINGS:

Figure 1a shows a sectional view of a mechanism for sensing and regulating pressure in a discharge line in accordance with the present invention;

Figure 1b shows a detailed view of a flexible seal arranged on a second piston of the mechanism shown in figure 1a;

Figure 1b shows a detailed view of a vent of the mechanism shown in figure 1;

Figure 2 shows a sectional view of the mechanism shown in figure 1 connected with a pneumatic device in accordance with the present invention;

Figure 3 shows another view of the pneumatic device shown in figure 2.

DETAILED DESCRIPTION OF THE INVENTION

For thorough understanding of the present invention, reference is to be made to the following detailed description in connection with the above-described drawings. Although the present invention is described in connection with exemplary embodiments, the present invention is not intended to be limited to the specific forms set forth herein. It is understood that various omissions and substitutions of equivalents are contemplated as circumstances may suggest or render expedient. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the present invention. As used throughout this disclosure, the singular forms “a,” “an,” and “the” may include plural reference unless the context clearly dictates otherwise.

The present invention provides a mechanism for sensing and regulating pressure in a delivery line. More particularly, the present invention provides a mechanism for sensing and regulating pressure in a delivery line of a pneumatic or and hydraulic device delivering pressurized fluid there through. The mechanism has more repeatability and reliability compared to existing governor valves. Further, the mechanism is simple in construction. Furthermore, the mechanism is easily serviceable. Also, the mechanism is economical in operation.
Referring now to figure 1a, a sectional view of a mechanism 100 for sensing and regulating pressure in a discharge line 12 in accordance with the present invention is illustrated. In the present embodiment, the mechanism 100 is connected with a discharge line 12 a pneumatic device 80. The pneumatic device 80 is an air treatment and controlling unit. In the present embodiment, the pneumatic device 80 is an air treatment and controlling unit. The pneumatic device 80 is connected to a pneumatic braking system (not shown) of a vehicle. The pneumatic device 80 is connected with an air compressor (not shown). The air compressor supplies pressurized air to the air treatment and controlling unit. The pneumatic device 80 (air treatment and controlling unit) removes oil and moisture content in the received air from the air compressor and supplies moisture less pressurized air to the pneumatic braking system. The mechanism 100 includes a first piston 10, a second piston 20 and a flexible seal 40. The first piston 10 moves upwards when an input pressure of the fluid from the discharge line 12 of the pneumatic device 80 is more than a predefined pressure (Cut- out Condition).
In the present embodiment, the first piston 10 is connected with a compression spring 14 for exerting spring force on the first piston 10 for defining a pressure limit. The compression spring 14 is connected with a screw 16. The pressure limit is defined by compressing the compression spring 14 through the screw 16. In an alternative embodiment, the first piston 10 can be connected with a force exerting member such as a weight mass or a pneumatic pressure member and the like, which is capable to apply force on the first piston 10 for defining the pressure limit which is obvious to a person skilled in the art. The compression spring 14 is secured to a housing 50. As the compression spring 14 is secured with the mechanism 100 and to the housing 50, the mechanism 100 is secured to the housing 50. The housing 50 is attached to a body of the pneumatic device 80, thereby assembling the mechanism 100 to the pneumatic device 80. The second piston 20 is arranged within the first piston 10 for opening and closing a pneumatic control line 60 connected with the pneumatic device 80 (refer figure 1b and figure 2).
In present embodiment, the first piston 10 is connected to the second piston 20 through a plunger spring 22 connected there between for providing retention force to the second piston 20, when the second piston 20 closes the pneumatic control line 60. In an alternative embodiment, the first piston 10 is connected to the second piston 20 without the plunger spring 22 connected there between. Piston seals (not shown) are arranged between the first piston 10 and the second piston 20 for reducing internal leakage there between.
A passage 30 is configured through the first piston 10 and the second piston 20 for releasing the received fluid from the discharge line 12 of the pneumatic device 80 to the atmosphere when the input pressure of the fluid is less than the predefined pressure (cut-in condition). The passage 30 includes a port 34 (refer figure 1b) configured in the second piston 20 for receiving air. The received air from the port 34 passes through the passage 30 via a port 34.The received air through the passage 30 is release to the atmosphere through a vent 32.

The flexible seal 40 (refer figure 1b) is arranged on the second piston 20 opens the passage 30 by closing port 34 when the pressure is below the predefined pressure for maintaining the pressure level in the pneumatic device 80. The flexible seal 40 closes the passage 30 by closing the port 34, when the first piston 10 moves upward for passing fluid to the pneumatic control line 60 as a signal. The signal instructs pressure creating elements of the pneumatic device 80 such as the air compressor or a relief valve for reducing pressure development in the pneumatic device 80. It may be obvious knowledge to person ordinarily skilled in the art to configure the pneumatic device 80, which reduces the delivery pressure upon receiving the signal, specifically the signal is an unloading trigger signal to the air compressor connected with the pneumatic device 80.

For example, the mechanism 100 connected with the air treatment and controlling unit sends the signal to an unloader sub assembly (which is inbuilt in the air treatment and controlling unit) and to the air compressor for unloading operation. The unloading operation reduces the pressure developed inside the air compressor and delivers pressurized fluid with reduced pressure to the air treatment and controlling unit.

Further, the flexible seal 40 opens and closes the port 34 upon movements of the first and second pistons (10 & 20) caused by the pressurized fluid acting on the first piston 10. The mechanism 100 is connected with the pneumatic device 80 for regulating pressure delivered from the pneumatic device 80.

In an alternative embodiment, the first piston 10 and the second piston 20 are integral. The flexible seal 40 is arranged on the first piston 10 opens the passage when the pressure is below the predefined pressure for maintaining the pressure level in the pneumatic or hydraulic device. The flexible seal 40 closes the passage when the first piston 10 moves upward for passing fluid to the pneumatic or hydraulic control line as a signal, thereby regulates system pressure of the pneumatic or hydraulic device.
In an alternative embodiment, the mechanism 100 can be connected to a delivery line of a pneumatic or a hydraulic device for sensing and regulating the pressure. The pneumatic device can be an air compressor or a blower or an air pump and the like. The hydraulic device can be a hydraulic pump, a hydraulic motor and the like.

The mechanism 100 has an advantage of sensing and regulating pressure in the discharge line 12 through which pressurized fluid is discharged. . The mechanism 100 regulates the pressure in the discharge line 12 with movements of simple mechanical elements such as pistons (10& 20) and the flexible seal 40. The functioning of the first piston 10 and the second piston 20 is consistent with repeated number of operations. Therefore, the mechanism 100 has more repeatability compared to existing governor valves (Pressure regulation mechanism). Also, the functioning elements of the mechanism 100 such as the first piston 10, the second piston 20 and the flexible seal 40 performs their functions with varied pressure loads within their permissible limits. Hence, the mechanism 100 is more reliable compared to the existing governor valves. The mechanism 100 is composed of simple mechanical elements such as the first piston 10, the second piston 20, the flexible seal 40 and the like made the mechanism 100 simple in construction. An operator can easily able to disassemble the mechanism 100 from the pneumatic device for service purpose without intercepting the function of the mechanism 100. Therefore, the mechanism 100 is easily serviceable. Also, the mechanism 100 does not require any additional source of energy such as electric power, pneumatic power and the like for performing its function. Therefore, the mechanism 100 is economical in operation.

The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the present invention to the precise forms disclosed, and obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the present invention and its practical application, and to thereby enable others skilled in the art to best utilize the present invention and various embodiments with various modifications as are suited to the particular use contemplated. It is understood that various omissions and substitutions of equivalents are contemplated as circumstances may suggest or render expedient, but such omissions and substitutions are intended to cover the application or implementation without departing from the spirit or scope of the claims of the present invention.
,CLAIMS:WE CLAIM:
1. A mechanism for sensing and regulating pressure in a discharge line, the mechanism comprising:
a first piston moves upwards when an input pressure of fluid received from the discharge line of a pneumatic or and a hydraulic device is more than a predefined pressure;
a second piston arranged within the first piston for opening and closing of a pneumatic or and hydraulic control line connected with the pneumatic or hydraulic device ;
a passage configured through the first piston and the second piston for releasing the received fluid from the discharge line of the pneumatic device to the atmosphere when the input pressure of the fluid is less than the predefined pressure; and
a flexible seal arranged on the second piston opens the passage when the pressure is below the predefined pressure for maintaining the pressure level in the pneumatic or hydraulic device and closes the passage when the first piston moves upward for passing fluid to the pneumatic control line as a signal, thereby regulates the discharge pressure from the pneumatic or hydraulic device.

2. The mechanism as claimed in claim 1, wherein the pneumatic device is an air treatment and controlling unit.

3. The mechanism as claimed in claim 1, wherein the first piston is connected with a compression spring for exerting spring force on the first piston for defining a pressure limit.

4. The mechanism as claimed in claim 1, wherein the passage includes a port configured in the second piston for receiving air.

5. The mechanism as claimed in claim 1, wherein the flexible seal opens and closes the port upon movements of the first and second piston caused by the pressurized fluid acting on the first piston.

6. The mechanism as claimed in claim 1, wherein the first piston is connected to the second piston through a plunger spring connected there-between for providing retention force to the second piston when the second piston closes the pneumatic control line.

7. The mechanism as claimed in claim 1, wherein the first piston and the second piston is integral.

8. The mechanism as claimed in claim 1, wherein the flexible seal is arranged on the first piston opens the passage when the pressure is below the predefined pressure for maintaining the pressure level in the pneumatic or hydraulic device and closes the passage when the first piston moves upward for passing fluid to the pneumatic or hydraulic control line as a signal, thereby regulates the discharge pressure from the pneumatic or hydraulic device.

9. The mechanism as claimed in claim 2, wherein the air treatment and controlling unit is connected with an air compressor.

10. The mechanism as claimed in claim 2, wherein the air treatment and controlling unit is connected to a pneumatic braking system of a vehicle.