Claims:1. A rotary mechanism for switching an electrical switch, said mechanism comprises:
a housing;
a vertical gear located on a plane substantially perpendicular to the axis of a horizontal gear;
wherein the vertical gear operatively coupled on top of the horizontal gear;
a horizontal gear connector that lies in a plane substantially perpendicular to the horizontal gear;
wherein the horizontal gear is operatively engaged to the horizontal gear connector by a pin and nut arrangement;
wherein the horizontal gear connector further comprises of a duality of slots;
wherein the pin and nut ensures that there is no friction between the horizontal gear and the horizontal gear connector;
a duality of mechanism pins operatively engages a coupler to the horizontal gear connector;
wherein the horizontal gear connector and coupler are coupled to a contact system of a switch;
a duality of mechanism springs housed over a duality of spring arms;
wherein the lower ends of each spring arm is operatively engaged to each slot of the horizontal gear connector by a mechanism pin;
wherein a duality of support pins supports top end of a mechanism spring and spring arm pair;
wherein the mechanism springs store energy for operating the rotary mechanism;
wherein rotation of the vertical gear compresses the mechanism springs until dead center position.

2. The rotary mechanism as claimed in claim 1, wherein the horizontal gear comprises a plurality of slots.

3. The rotary mechanism as claimed in claim 1, wherein the horizontal gear connector comprises a plurality of protrusions.

4. The rotary mechanism as claimed in claim 1, wherein the vertical gear comprises a plurality of protrusions.

5. The rotary mechanism as claimed in claims 2 and 3, wherein the plurality of protrusions is operatively engaged to the plurality of slots.

6. The rotary mechanism as claimed in claim 1, wherein the horizontal gear is optionally engaged to the horizontal gear connector by a rivet.

7. The rotary mechanism as claimed in claim 1, wherein as the vertical gear is rotated by 90 degrees, the horizontal gear connector is at dead center position of the mechanism springs.

8. The rotary mechanism as claimed in claim 7, wherein at dead center position the horizontal gear is locked between the protrusions of the vertical gear.

9. The rotary mechanism as claimed in claim 7, wherein at dead center position the protrusions of the horizontal gear connector are free to rotate in the slots of the horizontal gear.

10. The rotary mechanism as claimed in claims1 to 9, wherein the energy stored in the mechanism springs allows the horizontal gear connector and coupler to rotate post the dead center position without moving the horizontal gear and the vertical gear.

11. The rotary mechanism as claimed in claim 1, wherein the motion of the contact system is independent of the motion of the vertical gear once the contact system rotates post the dead center position.

12. The rotary mechanism as claimed in claim 1, wherein angular displacement of the horizontal gear is about 50%.

13. The rotary mechanism as claimed in claim 1, wherein the contact system is not influenced by external driving forces.

14. The rotary mechanism as claimed in claim 1, wherein mass of rotating components is significantly reduced.

15. The rotary mechanism as claimed in claim 14, wherein the opening or closing velocity of the contact switch is higher.

16. The rotary mechanism as claimed in any one of claims 1 to 15, wherein the vertical gear, the horizontal gear connector, the pin, the nut, the coupler is accessible from outside of the housing.
, Description:FIELD OF THE INVENTION

[001] The subject matter of the present invention, in general, relates to a mechanism to drive an electrical switching device and more particularly, pertains toa rotary mechanism for switching electrical switch devices.

BACKGROUND OF INVENTION

[002] Switching devices are instruments employed for opening and closing an electric circuit. A switching device comprises at least one pole and a control device adapted to open and close said pole. Examples of switching devices include switches and switch-fuses.

[003] All switching devices have a 0 (OFF) position, wherein the poles of the switching device are open, and an I (ON) position, wherein the poles of the switching device are closed. The positions of the poles of the switching device are changed by rotating the main shaft of the switching device. For rotating the main shaft, switching devices are provided with an actuator having a 0 position and an I position, which correspond to the 0 position and I position of the switching device. Some switching devices also have a testing position, wherein the poles of the switching device are open, but the position of the auxiliary contacts corresponds to the I position of the switching device.

[004] Conventional switching devices comprise of a control shaft and a working shaft installed in a frame part, wherein the control shaft is rotatable and adapted to turn the working shaft, which, in turn, is adapted to change the position of the poles of the switching device. The control shaft of such a switching device is typically substantially transverse relative to the working shaft.

[005] Electrical switching apparatus, such as a switch disconnector disconnects or isolates a switch to ensure that an electrical circuit is completely de-energized. It not only provides isolation, it is also capable of making, carrying and breaking currents under normal circuit conditions that may include the specified operating overload conditions for specific time periods, and under specified abnormal circuit conditions such as those short circuit for a specified time. These switch disconnectors find diverse applications in motor control centers, in switchboards and as main switches in various equipment and machines. Such switches are ideal for withstanding higher short circuit currents for short time duration.

[006] Reference is made to 331/MUM/2012, wherein a rotary cam mechanism is disclosed. The rotary cam mechanism comprises a duality of modular mechanism connected back to back by a single integrated actuating shaft; a plurality of spring loaded spring arms attached to said integrated actuating shaft; a plurality of horizontal rotors for coupling said mechanism to a contact shaft; a single cam driving said horizontal rotors thus driving said contact shaft; said cam arranged to accommodate an idle rotation of said integrated actuating shaft during which said horizontal rotor is stationary; said integrated actuating shaft further coupled to a multi-toothed cam that lies on a plane perpendicular to the axis of the vertical rotor; said multi toothed cam element positively coupled to either of the horizontal rotors and a plurality of spring loaded pins a housing for accommodating said rotary cam mechanism. The mechanism described in this prior art can be manually influenced by the user by applying external force during abusive operation and as a result contact system motion is influenced by User affecting the electrical performance of the mechanism.

[007] Reference is also made to US 7368676 B2,wherein a switching device with a frame is disclosed. In the switching device, an actuator is adapted to rotate a main shaft of the switching device and rotatable around an axis of rotation, the actuator having a 0 position, I position and a first dead point between the 0 position and the I position, the I position being located by a given angle (a6) in a first direction relative to the 0 position. The actuator also has a testing position, the testing position being located by a predetermined angle (ß6) in a second direction relative to the 0 position, the second direction being opposite relative to the first direction.

[008] Reference is also made to US 7679018 B2, wherein a switching device is disclosed. The switching device includes a working shaft and a control shaft installed in a frame, the control shaft being rotatable and adapted to turn the working shaft, and the working shaft being adapted to change the position of poles of the switching device. One of the two shafts passes through the other shaft.

[009] In the existing rotary mechanisms, it is possible for the post dead center to be manually influenced by an operator by applying suitable external force thereby rendering the conventional mechanisms vulnerable to sabotage. Therefore, there is a need for a rotary cam mechanism wherein the operator operating the mechanism will have no influence on the velocity of the contact opening/closing and will also not be able to stop or cause any hindrance to contact system motion thereby providing reliability to the switch.

SUMMARY OF THEINVENTION

[0010] The following presents a simplified summary of the invention in order to provide a basic understanding of some aspects of the invention. This summary is not an extensive overview of the present invention. It is not intended to identify the key/critical elements of the invention or to delineate the scope of the invention. Its sole purpose is to present some concept of the invention in a simplified form as a prelude to a more detailed description of the invention presented later.

[0011] An object of the present invention is to provide an independent mechanism for an electrical device with rotary contact system.

[0012] Another object of the present invention is to provide a rotary cam mechanism independent of operator influence on contact opening or closing velocity.

[0013] Another object of the present invention is to provide a rotary cam mechanism not influenced by the driving force or speed of an operator.

[0014] Yet another object of the present invention is to provide a mechanism that transfers energy from vertical motion to horizontal motion.

[0015] Yet another object of the present invention is to provide a mechanism that converts rotary motion of a particular direction to rotary motion in a direction perpendicular to it.

[0016] Yet another object of the present invention is to provide a rotary cam mechanism employing gear and linkages with higher efficiency.

[0017] Yet another object of the present invention is to provide a rotary cam mechanism for switching an electrical switch device.

[0018] Yet another object of the present invention is to provide a rotary cam mechanism with only 50% angular displacement to a horizontal gear.

[0019] Yet another object of the present invention is to provide a rotary cam mechanism where a higher gear ratio between driver and driven mechanism may be achieved.

[0020] Yet another object of the present invention is to provide a rotary cam mechanism requiring low operating torque owing to higher gear ratio.

[0021] Yet another object of the present invention is to provide reduction in the rotating mass (vertical gear, operating shaft and handle are stationary during rotation of moving contacts) as compared to the conventional mechanisms.

[0022] Yet another object of the present invention is to provide a rotary cam mechanism with higher opening and closing velocity owing to reduction in mass movement of inertia of rotating parts.

[0023] The present invention is directed to proper operation of an electrical switch by ensuring that the switch operation, i.e., ON to OFF and OFF to ON is not influenced by the driving forces and/or speed of an operator. In particular, a rotary cam mechanism that would drive the contact system of the switch with same velocity as achieved through the stored energy of the springs regardless of any external force applied by the operator is disclosed. Therefore, the contact system velocity remains unaltered during operation irrespective of the end user. It also ensures that the contact closing and opening mechanism is smooth without it getting affected by external means. This compact rotary cam mechanism transfers energy from vertical motion to horizontal motion and converts rotary motion in one direction to rotary motion in the direction perpendicular to the first direction of motion by using gear and linkages at a higher efficiency.

[0024] The present invention discloses a rotary mechanism for switching the electrical switch device by converting vertical rotatory motion to horizontal rotatory motion through gear linkages. The rotary mechanism comprises of a vertical gear coupled to a horizontal gear that has slots provided in it. The horizontal gear is connected to a horizontal gear connector via a pin and a nut. This pin and nut arrangement holds the horizontal gear-horizontal gear connector assembly together while also ensuring that there is no friction between the horizontal gear-horizontal gear connector. Protrusions provided in the horizontal gear connector within the slots of the horizontal gear. Two mechanism pins connect a coupler and the horizontal gear connector. Two spring arms and two mechanism springs store the energy required to operate the rotary mechanism.

[0025] Other aspects, advantages, and salient features of the invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses exemplary embodiments of the invention.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

[0026] The above and other aspects, features, and advantages of certain exemplary embodiments of the present invention will be more apparent from the following description taken in conjunction with the accompanying drawings in which:

[0027] Figure 1 illustrates the side, top and general view according to one implementation of the present invention.

[0028] Figure 2 illustrates the components of a rotary mechanism according to one implementation of the present invention.

[0029] Figure 3 illustrates the front, side and sectional view of the rotary mechanism assembly in OFF position according to another implementation of the present invention.

[0030] Figure 4 illustrates the front, side and sectional view of the rotary mechanism assembly in 25-degrees post OFF position according to another implementation of the present invention.

[0031] Figure 5 illustrates the front, side and sectional view of the rotary mechanism assembly in dead center position according to another implementation of the present invention.

[0032] Figure 6 illustrates the front, side and sectional view of the rotary mechanism assembly in 25-degrees post dead center position according to another implementation of the present invention.

[0033] Figure 7 illustrates the front, side and sectional view of the rotary mechanism assembly in ON position according to another implementation of the present invention.

[0034] Figure 8 illustrates the front, side and sectional view of the rotary mechanism assembly in 25-degrees post ON position according to another implementation of the present invention.

[0035] Figure 9 illustrates the front, side and sectional view of the rotary mechanism assembly in dead center position according to another implementation of the present invention.

[0036] Figure 10 illustrates the front, side and sectional view of the rotary mechanism assembly in 25-degrees post dead center position according to another implementation of the present invention.

[0037] Figure 11 illustrates the front, side and sectional view of the rotary mechanism assembly in OFF position according to another implementation of the present invention.

[0038] Figure 12 illustrates the front, back and general view of the horizontal gear-horizontal gear connector assembly according to another implementation of the present invention.

[0039] Persons skilled in the art will appreciate that elements in the figures are illustrated for simplicity and clarity and may have not been drawn to scale. For example, the dimensions of some of the elements in the figure may be exaggerated relative to other elements to help to improve understanding of various exemplary embodiments of the present disclosure. Throughout the drawings, it should be noted that like reference numbers are used to depict the same or similar elements, features, and structures.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

[0040] The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of exemplary embodiments of the invention. It includes various specific details to assist in that understanding but these are to be regarded as merely exemplary.

[0041] Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope of the invention. In addition, descriptions of well-known functions and constructions are omitted for clarity and conciseness.

[0042] The terms and words used in the following description and claims are not limited to the bibliographical meanings, but, are merely used by the inventor to enable a clear and consistent understanding of the invention. Accordingly, it should be apparent to those skilled in the art that the following description of exemplary embodiments of the present invention are provided for illustration purpose only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.

[0043] It is to be understood that the singular forms “a”, “an”, and “the” include plural referents unless the context clearly dictates otherwise.

[0044] By the term “substantially” it is meant that the recited characteristic, parameter, or value need not be achieved exactly, but that deviations or variations, including for example, tolerances, measurement error, measurement accuracy limitations and other factors known to those of skill in the art, may occur in amounts that do not preclude the effect the characteristic was intended to provide.

[0045] Features that are described and/or illustrated with respect to one embodiment may be used in the same way or in a similar way in one or more other embodiments and/or in combination with or instead of the features of the other embodiments.

[0046] It should be emphasized that the term “comprises/comprising” when used in this specification is taken to specify the presence of stated features, integers, steps or component but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.

[0047] The subject invention lies in providing an independent mechanism for an electrical device with rotary contact system.

[0048] The present pertains to a rotary cam mechanism that would drive a contact system of a switch with the velocity achieved by the energy stored in its springs regardless of any external force applied by an operator, i.e., the contact system velocity remains unaltered during operation irrespective of the end user. It also ensures that the contact closing and opening mechanism is smooth without them being affected by external means. The rotary cam mechanism transfers energy from vertical motion to horizontal motion and converts rotary motion of one direction to rotary motion in a direction perpendicular by employing gear and linkages at a higher efficiency.

[0049] In one implementation, a rotary cam mechanism independent of operator influence on contact opening or closing velocity is provided for.

[0050] In one implementation, a rotary cam mechanism not influenced by the driving force or speed of an operator is provided for.

[0051] In another implementation, a mechanism that transfers energy from vertical motion to horizontal motion is provided for.

[0052] In another implementation, a mechanism that converts rotary motion of a particular direction to rotary motion in a direction perpendicular is provided for.

[0053] In another implementation, a rotary cam mechanism employing gear and linkages at a higher efficiency is provided for.

[0054] In another implementation, a rotary cam mechanism for switching an electrical switch device is provided for.

[0055] In another implementation, a rotary cam mechanism with only 50% angular displacement to a horizontal gear is provided for.

[0056] In another implementation, a rotary cam mechanism wherein a higher gear ratio between driver and driven mechanism is provided for.

[0057] In another implementation, a rotary cam mechanism requiring low operating torque is provided for.

[0058] In another implementation, reduction in the rotating mass when compared to conventional mechanisms is provided for.

[0059] In another implementation, a rotary cam mechanism with higher opening and closing velocity is provided for.

[0060] The present invention discloses a rotary mechanism (1) for switching the electrical switch device that converts vertical rotatory motion to horizontal rotatory motion through gear linkages. Figure 1 illustrates the side, top and general view of the rotary mechanism (1) illustrated in Figure 2. The rotary mechanism (1) consists of a vertical gear (2) coupled with a horizontal gear (7). The horizontal gear (7) has slots provided in it. This horizontal gear (7) is connected with horizontal gear connector (8) through a pin (9) and nut (10). Figure 12 illustrates the front, back and general view of the horizontal gear and horizontal gear connector assembly. This pin (9) and nut (10) arrangement holds the horizontal gear (7) and horizontal gear connector (8) assembly together and also ensures that there is no friction between horizontal gear (7) and horizontal gear connector (8). Instead of the pin (8) and nut (10) arrangement, riveting can be opted to hold gear assembly together. The protrusions provided in the horizontal gear connector (8) move inside the slots of the horizontal gear (7), as also illustrated in Figure 12.

[0061] The rotary mechanism (1) also has two mechanism pins (6) to connect the coupler (3) and the horizontal gear connector (8). Two spring arms (5) and two mechanism springs (4) are also present for the stored energy operation of the mechanism (1), as also illustrated in Figures 1 and 2.Considering the switch to be initially in OFF position as illustrated in Figure 3. When the vertical gear (2) is operated in anticlockwise direction, then the horizontal gear (7) which is coupled to it also starts moving. During this operation, the horizontal gear (7) and the horizontal gear connector (8) move together because of the coupling between the slots in horizontal gear (7) and the protrusions in horizontal gear connector (8) as illustrated in Figure 4.

[0062] The motion of this rotary assembly (1) compresses the mechanism springs (4) till the dead center position. By the time the vertical gear (2) has rotated by 90 degrees, the horizontal gear connector (8) has reached the dead center position of the mechanism springs (4). Also at this position, the horizontal gear (7) can rotate no further as it is locked between the teeth of the vertical gear (2) as illustrated in Figure 5.At this point the protrusions of the horizontal gear connector (8) are free to rotate in the slots of the horizontal gear (7) and owing to the stored energy of the mechanism springs (4), the horizontal gear connector (8) and coupler (3) rotate post the dead center position without moving the horizontal gear (7) and the vertical gear (2). This horizontal gear connector (8) and coupler (3) are connected to one another and can be coupled with the contact system of a switch thereby making the motion of the contact system independent of the motion of the vertical gear (2) as the contact system moves post the dead center position, as illustrated in Figures 6 and 7. Notably, during ON-OFF operation the process indicated herein above is repeated, as also illustrated in Figures 8,9,10 and 11.

[0063] Therefore, the drawback of existing rotary mechanisms that are vulnerable to manual influences of operators by the application of suitable external force thereby rendering such mechanisms prone to sabotage. The rotary cam mechanism disclosed herein does away with this vulnerability thereby providing reliability to the switch.

[0064] Although a simple, economic, cost effective and non-sabotageable rotary cam mechanism for switching an electrical switch device by converting vertical rotatory motion to horizontal rotatory motion through gear linkages has been described in language specific to structural features indicated, it is to be understood that the embodiments disclosed in the above section are not necessarily limited to the specific features or components or devices described therein. Rather, the specific features are disclosed as examples of implementations of a manually independent mechanism for electrical devices with rotary contact systems.

[0065] ADVANTAGES:

i. A manually independent mechanism.
ii. Need to provide only 50 % angular displacement to horizontal gear. Thus higher gear ratio between driver and driven can be achieved.
iii. Lesser operating torque due to higher gear ratio.
iv. Reduction in the rotating mass (Vertical gear, operating shaft, Handle are stationary during rotation of Moving contacts) as compared to conventional mechanism.
v. Higher opening and closing velocity for given mechanism spring force/Energy. Due to reduction in mass movement of inertia (I) of rotating parts.
vi. Contact system motion isn’t getting influenced by external driving force.
vii. Making and breaking electrical operations become more reliable as user can’t influence the contact system movement.