A MECHANICAL TRIPPABLE SWITCH MECHANISM
FIELD OF THE INVENTION
[001] The present invention generally relates to mechanical switching devices and more particularly embodiments of the invention relates to an improved mechanical switching mechanism.
PRIOR ART [002] Mechanical switching devices typically have two points ON or OFF. The actuation of push button causes the button to be in ON state. Actuating once more brings the test button to its OFF state. Some switching devices have a third position that corresponds to a tripped condition in which the switch comes back to OFF state due to actuation of a trip lever.
[003] In the invention, the force applied to the button or protrusion in the switch controls the movement of the protrusion. When the button is pressed in, it gets latched and the protrusion stays moved outwards. During the subsequent operation of the button, it gets de latched again.
[004] It is often required to a reset a switch or put the switch to a 'trip to off condition when the related mechanisms stop, or an override in faulty positions. Prior art will of this problem by mechanisms with very complicated profiles and complex assemblies are used to achieve this functionality or it is done through some electrical circuit arrangements. It is explained clearly in the referenced prior art.
SUMMARY OF THE INVENTION
[005] It is an object of the invention to provide an override switch. More particularly, it is an object of the invention to provide a switch that has mechanism provided within for safe operation during short circuit.
[006] It is also an object of the invention to provide an override switch that is compact by advantageously employing a rotary cam coupled with a hook spring and a trip switch.

BRIEF DESCRIPTION OF THE DRAWINGS
[007] So that the manner in which the above recited features of the present
invention can be understood in detail, a more particular description of the
invention, briefly summarized above, may be had by reference to various
embodiments, some of which are illustrated in the appended drawings. It is to be
noted, however, that the appended drawings illustrate only typical embodiments of
this invention and are therefore not to be considered limiting of its scope, for the
invention may admit to other equally effective embodiments.
[008] FIG. 1 represents an exploded view of the switch according to an
embodiment of the invention.
[009] Figure 2 represents the normal or OFF position of the switch according to
an embodiment of the invention.
[0010] Figure 3 represents the switching ON of the embodiment while the handle
is open.
[0011] Figure 4 represents the isometric switch in fully ON state.
[0012] Figures 5a and 5b represents test switch assembly being switched OFF. The
Isometric view is as shown by Figure 5a.
[0013] Figure 6 shows how the switch can be brought to OFF state with the
actuation of trip lever.
DETAILED DESCRIPTION OF INVENTION
[0014] The invention provides an override switch. More particularly embodiments
of the invention provide a switch that has mechanisms provided within for safe
operation during short circuit.
[0015] The invention also provides an override switch that is compact by
advantageously employing a rotary cam coupled with a hook spring and a trip
switch.
[0016] Embodiments of the invention advantageously utilize a rotary cam and
hook spring arrangement for switching operations. Further, employment of a trip
switch synergistically with the said rotary cam and hook spring arrangement
enables the override function of the switch.

[0017] Various embodiments of the invention that provide the override switch are described in detail herein.
[0018] FIG. 1 represents an exploded view^ of the above mentioned embodiment. The enclosures (1) and (9) houses the push button(2), mounted over a spring (3) to actuate a cam (4) which drives the actuator (7) by compressing the spring (5) and latching on to the trip lever(8) having an indicator which is visible through a transparent window(6).
[0019] Figure 2 represents the normal or OFF position of the switch according to an embodiment of the invention.
[0020] Figure 3 represents the switching ON of the embodiment while the handle is open. The pushbutton (2) moves down and touches the cam (4) at the profile (4d) as shown. This embarks the motion of a pin joint comprising of features (7a) and (4c). Simultaneously, the profile (4b) slides over the arm (8b) of the trip lever (8). The springs (3) and (5) are getting compressed thereby storing energy for switch OFF operation.
[0021] Figure 2 also features indication feature provided on the trip lever (8) with red color for ON position indication (8d) and green color for OFF position (8c). [0022] Figure 4 represents the isometric switch in fully ON state. The profile (4b) of the cam(4) latches onto the arm (8b) and remains intact thereafter. The pushbutton (2) once released after this, returns back as there in nothing restraining its movement. This stimulates the rotation of indicating features (8c) and (8d) which are pivoted about the circular profile (8f) as shown thereby giving the proper indication to the user. The flexible arm (8a) of the trip lever (8) flexes and provides the necessary force for the arm (8b) to latch onto the profile (4b). [0023] Figures 5a and 5b represents test switch assembly being switched OFF. The isometric view is as shown by Figure 5a. The test button (2) when pressed down results in the engagements of the profile (2a) on the button (2) and integral lever (4a) on the cam (4). This lever (4a) being in rigid contact with the trip actuator (4e) and pivoted at the hinge (4f) results in the movement of the trip actuator (4e) upwards pushing the arm (8b) away from the latching profile (4b) on the cam. This initiates the cam (4) to rotate clockwise and return to the state as shown in Figure

1. The energy stored in the spring (5) assists the cam to rotate fast. Simultaneously the flexible arm (8e) of the trip lever (8) unbends due to its elastic nature and returns the arm (4e) back to its normal state as shown in Figure 1 giving the proper indication of the state of the switch through the transparent window (6). [0024] Figure 6 shows how the switch can be brought to OFF state with the actuation of trip lever (8) independent of the push button (2) which is used normally. When force is applied on the trip arm (8e) of the trip lever (8) it moves down flexing the arm (8a) more. The trip lever (8) being pivoted at the hinge (8f)sets the arm (8b) in upward motion, disengaging it from the profile (4b) of the cam(4). This sets the cam to rotate freely which is assisted by the energy stored in the spring (5). So the cam returns to its normal position as shown pulling the actuator (7) back as well. Thus the switch is brought to OFF state. [0025] Along with this the proper indication of the status of the switch through the indicator window, due to the unbending of the flexible arm (8a) and the downward movement of the arm (8b) once the cam starts moving out of its latched position, is initiated.
[0026] The invention described in detail herein and as illustrated by examples advantageously provides a switch that is compact and enables a override function to the switch.
[0027] The foregoing description of the invention has been set for merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to person skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof

We claim:
1. A mechanical switching mechanism comprising of a push button, a spring mounted over said push button, a rotary cam actuated by the said spring, an actuator driven by said rotary cam compressed by the said spring, a trip lever latched to the said actuator and having an indicator housed in a transparent window.
2. A mechanical switching mechanism of claim 1, wherein the said mechanism is utilized for turning ON and/or turning OFF of a switch comprising the said mechanism.
3. A mechanical switching mechanism of claim 1, wherein the said switch utilizing the said switching mechanism can be brought to ON state by a first press of the said pushbutton resulting downward movement of the said pushbutton that generates a contact of the said pushbutton with the said cam at the said profile and further wherein the said contact of the said cam at the said profile enables the motion of a pin joint and resulting in sliding of the said profile over the said arm of the said trip lever.
4. A mechanical switching mechanism of claim 1, wherein the said switch utilizing the said switching mechanism can be brought to OFF state by a second press of the said pushbutton that engages the said profile on the said pushbutton and/or engages an integral lever on said cam
5. A mechanical switching mechanism of claim 1, further wherein the said engagement of the said lever in rigid contact with said trip actuator and pivoted at the hinge results in the movement of said trip actuator upwards pushing the said arm in an outward direction from said latching profile on said cam that generates clockwise rotation of the said cam.
6. A mechanical switching mechanism of claim 1, further wherein the said mechanism utilizes the said trip lever for providing an override mechanism.
7. A mechanical switching mechanism of claim 1, wherein the said switch utilizing the said switching mechanism can be brought to OFF state with the said actuation of said trip lever independent of the said push button.

8. A mechanical switching mechanism of claim 1, wherein the said switching
mechanism having the said indicator has means provided on the trip lever to
indicate ON and/or OFF position of the switch.
9. A mechanical switching mechanism of claim 1, wherein the said means
provided on the said indicator in a preferred embodiment of the invention is a
color indicator and further wherein the said color is red color for ON position
indication and green color for OFF position indication.