The present invention generally relates to the field of automobile switches. Particularly, the present invention relates to a switch for use in low current applications.
BACKGROUND OF THE INVENTION
In general, vehicles are equipped with a variety of control switches having different mechanical and electrical configurations. Generally, the control switches has mechanical configuration such as a push type or a hinge type or a slide type or a rocker type configuration etc. and the electrical configuration such as utilization of said switches for high, low or ultra low current applications.
A variety of vehicle's control switches are available in the market. While switch having different mechanical and electrical configurations have been proposed, there is still a need to provide a switch which is simple in terms of its construction, which is easy to manufacture, which can be manufactured at a reasonable price, which occupies less space, which has high precision and which can be used for low current applications.
SUMMARY OF THE INVENTION
This summary is provided to introduce a selection of concepts in a simplified format that are further described in the detailed description of the invention. This summary is neither intended to identify key or essential inventive concepts of the invention, and nor is it intended for determining the scope of the invention.
In accordance with an embodiment, the present invention provides a low current switch which comprises a casing with an aperture. The casing defines a first storage space. The switch comprises a push button switching element being accommodated in the first storage space. The push button switching element comprises an operating member. Further, the switch comprises a top cover which includes an aperture. The top cover envelops the casing to define a second storage space. Furthermore, a plunger is located at least partly in the second storage space. The plunger comprises a first end and a second end. The first end is adapted to traverse via the aperture in the top cover to receive an actuating force, and the second end is adapted to cooperate with the operating member of the push button switching element to transfer said actuating force to the operating member of the push button switching element, thereby actuating the push button switching element.

To further clarify advantages and features of the present invention, a more particular description of the invention will be rendered by reference to specific embodiments thereof, which is illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail with the accompanying drawings.
BRIEF DESCRIPTION OF THE FIGURES:
In order that the invention may be readily understood and put into practical effect, reference
will now be made to exemplary embodiments as illustrated with reference to the
accompanying drawings, where like reference numerals refer to identical or functionally
similar elements throughout the separate views. The figures together with a detailed
description below, are incorporated in and form part of the specification, and serve to further
illustrate the embodiments and explain various principles and advantages, in accordance with
the present invention where:
Figure 1 illustrates an exploded view of a low current switch in accordance with an
embodiment of the present invention;
Figure 2 illustrates an exploded view of a push button switching element in accordance with
an embodiment of the present invention;
Figure 3 illustrates a perspective view of the moving contact mechanism forming part of the
push button switching element in accordance with an embodiment of the present invention;
Figure 4 illustrates a top view of yet another moving contact mechanism forming part of the
push button switching element in accordance with an embodiment of the present invention;
Figures 5a, 5b and 5c illustrate a front, a top and a side view, respectively of a further
moving contact mechanism forming part of the push button switching element in accordance
with an embodiment of the present invention;
Figures 6a and 6b illustrate the change in the distance of the first channel between an
actuated state and a non-actuated state of the switch.
Figure 7 illustrates the push button switching element in OFF state in accordance with an
embodiment of the present invention;
Figure 8 illustrates the push button switching element in ON state in accordance with another
embodiment of the present invention;
Figure 9 illustrates an exploded view of a push button switching element in accordance with
an another embodiment of the present invention;

Figure 10 illustrates the push button switching element in OFF state in accordance with an embodiment of the present invention; and
Figure 11 illustrates the push button switching element in ON state in accordance with another embodiment of the present invention.
It may be noted that to the extent possible, like reference numerals have been used to represent like elements in the drawings. Further, skilled artisans will appreciate that elements in the drawings are illustrated for simplicity and may not have been necessarily been drawn to scale. For example, the dimensions of some of the elements in the drawings may be exaggerated relative to other elements to help to improve understanding of aspects of the present invention. Furthermore, the one or more elements may have been represented in the drawings by conventional symbols, and the drawings may show only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the drawings with details that will be readily apparent to those of ordinary skill in the art having benefit of the description herein.
Detailed Description of the Invention:
For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.
It will be understood by those skilled in the art that the foregoing general description and the following detailed description are explanatory of the invention and are not intended to be restrictive thereof.
As used in the description herein and throughout the claims that follow, the meaning of "a," "an," and "the" includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of "in" includes "in" and "on" unless the context clearly dictates otherwise.

Reference throughout this specification to "an aspect", "another aspect" or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrase "in an embodiment", "in another embodiment" and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.
The terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a device that comprises a list of steps does not include only those steps but may include other steps not expressly listed or inherent to such process or method. Similarly, one or more devices or sub-systems or elements or structures or components proceeded by "comprises... a" does not, without more constraints, preclude the existence of other devices or other sub-systems or other elements or other structures or other components or additional devices or additional sub-systems or additional elements or additional structures or additional components.
As used herein, and unless the context dictates otherwise, the terms "coupled to", "connected to", "operably connected to", "operatively connected to" are intended to include both direct connection / coupling (in which two elements that are coupled / connected to each other contact each other) and indirect coupling / connection (in which at least one additional element is located between the two elements). Therefore, the terms "coupled to" and "coupled with" are used synonymously. Similarly, the terms "connected to" and "connected with" are used synonymously.
Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skilled in the art to which this invention belongs. The device, methods, and examples provided herein are illustrative only and not intended to be limiting.
The use of any and all examples, or exemplary language (e.g. "such as") provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.

Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written description of all Markush groups used in the appended claims.
Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.
Referring to Figure 1, which is an exploded view of a low current switch (10) in accordance with an embodiment of the present invention. The switch (10) comprises a casing (12) with an aperture. The casing (12) defines a first storage space. The switch (10) comprises a push button switching element (100, 200) being accommodated in the first storage space. The push button switching element (100, 200) comprises an operating member. Further, the switch (10) comprises a top cover (14) which includes an aperture. The top cover (14) envelops the casing to define a second storage space. Furthermore, a plunger (16) is located at least partly in the second storage space. The plunger (16) comprises a first end and a second end. The first end is adapted to traverse via the aperture in the top cover (14) to receive an actuating force, and a second end adapted to cooperate with the operating member of the push button switching element (100 , 200) to transfer said actuating force to the operating member of the push button switching element (100, 200).
In an embodiment of the invention, the plunger (16) is located at least partly in the first storage space. The second end of the plunger (16) is adapted to traverse via the aperture in the casing (12) to cooperate with the operating member of the push button switching element (100 , 200) to transfer said actuating force to the operating member of the push button switching element (100 , 200).
In an embodiment of the invention, the plunger (16) defines a flange disposed between the first and the second end. A resilient member (18) is disposed between the casing (12) and the flange of the plunger (16) such that the resilient member (18) is adapted to provide a restoring force to the plunger (16).

Referring to Figure 2, which is an exploded view of a push button switching element (100) in accordance with an embodiment of the present invention, the push button switching element (100) comprises a housing (102) which defines an open end (102a), an opposing closed end (102b) having an aperture (102c) therein, and an internal space. A base (104) is adapted to cooperate with the housing (102) thereby sealing the open end (102a) of the housing (102). Further, the push button switching element (100) comprises a pair of fixed contact terminals (106a, 106b). Furthermore, the push button switching element (100) further comprises an operating member (108) adapted to move towards the base (104) upon actuation. The operating member (108) defines a first end (108a) and a second end (108b), where in a first end (108a) is adapted to be located outside the housing, and a second end (108b) is adapted to be located within the internal space. Furthermore, a moving contact mechanism (110) is operably coupled to the operating member (108), and is adapted to establish an electrical path between the pair of fixed contact terminals (106a, 106b), upon actuation of the operating member (108).
In an embodiment of the invention, the push button switching element (100) further comprises a resilient member (112) disposed between the base (104) and the operating member (108) to provide a restoring force to the operating member (108).
In an embodiment of the invention, the base (104) is provided with a pair of non-conductive pillars (114a, 114b). The non-conductive pillars (114a, 114b) project towards the opposing end (102b) of the housing (102) and are adapted to hold the pair of fixed contact terminals (106a, 106b). In simpler words, each non-conductive pillar (114a, 114b) is provided with an internal space for snugly accommodating each fixed contact terminal (106a, 106b).
Referring to Figure 3 there is illustrated a perspective view of the moving contact mechanism (110) that forms part of the push button switching element (100) in accordance with an embodiment of the present invention. The moving contact mechanism (110) comprises a plate member (116) having four corners and four "L" shaped leg members (118) extending downward from the four corners. The moving contact mechanism (110) further comprises a first pair of contact making members (120a) and a second pair of contact making members (120b) formed at the ends of the four L-shaped leg members (118), such that upon actuation, the first pair of contact making members (120a) come in contact with the first fixed contact terminal (106a) and the second pair of contact making members (120b) come in contact with the second fixed contact terminal (106b). In an embodiment of the invention, the first pair of

contact making members (120a) and the second pair of contact making members (120b) project towards the opposing end (102b) of the housing (102).
In an alternative embodiment, the moving contact mechanism (110) may comprise a plate member (116) having four corners. The moving contact mechanism further comprises a first pair of contact making members (120a) and a second pair of contact making members (120b) formed at the four corners, such that upon actuation, the first pair of contact making members (120a) come in contact with the first fixed contact terminal (106a) and the second pair of contact making members (120b) come in contact with the second fixed contact terminal (106b). The moving contact mechanism (110) constructed in accordance with this embodiment is shown in Figure 4.
In yet another alternative construction, the moving contact mechanism (110) comprises a plate member (116) having four corners. The moving contact mechanism (110) further comprises two planar surfaces extending downward. The moving contact mechanism further comprises a first pair of contact making members (120a) formed on the first planar surface and a second pair of contact making members (120b) formed on the second planar surface, such that upon actuation, the first pair of contact making members (120a) come in contact with the first fixed contact terminal (106a) and the second pair of contact making members (120b) come in contact with the second fixed contact terminal (106b).The moving contact mechanism (110) constructed in accordance with this embodiment is shown in Figures 5a, 5b, and 5c, which pertain to front, top and side views of the moving contact mechanism (HO).
While the moving contact members shown in Figure 3, Figure 4 and Figure 5 are marginally different in terms of their construction, the functioning of all these three moving contact members is substantially similar and which is being elaborated in the following paragraphs.
In particular, referring to Figure 6(a), it can be seen that the first pair of contact making members (120a) converge towards each other to define a first channel having a minimum distance and the thickness of the first fixed contact terminal (106a) is greater than the distance of the first channel. For instance, if the distance of the first channel is X millimetre then the thickness of the first fixed contact terminal (106a) could be between X + (5-30% of X) millimetres. When the moving contact mechanism is actuated, as shown in Figure 6(b), the first pair of contact making members (120a) first comes in abutting relationship with the

fixed contact member. Since the thickness of the fixed contact member is greater than the first channel having the minimum distance, the first fixed contact terminal (106a) has a tendency of pushing the first pair of contact making members (120a) away from one another. Thus, the distance of the first channel increases.
However, when the first fixed contact terminal (106a) ceases to abut the first pair of contact making members (120a) i.e. when the switch returns from the state as shown in Figure 6(b) to the state as shown in Figure 6(a), the first pair of contact making members (120a) attain the original shape (i.e. they once again converge towards each other to once again define the first channel of minimum distance). Thus, the first pair of contact making members (120a) inherently apply a restoring force towards each other or a positive force on the first fixed contact terminal (106a). Although not illustrated, even the second pair of contact making members function in the same manner as described thereby selectively providing electrical path between the first fixed contact terminal (106a) and the second fixed contact terminal (106b).
While Figure 6(a) and Figure 6(b) show the functional relationship between the first fixed contact terminal (106a) and the first set of contact making members (120a), Figure 7 shows the push button switching element (100) in OFF position (which corresponds to Figure 6(a)) and Figure 8 shows the push button switching element (100) in ON position (which corresponds to Figure 6(b)).
In an embodiment of the invention, the operating member (108) defines a plate structure that comes in contact with the plate member (116) of the moving contact mechanism (110). The plate structure (116) helps in providing substantially equal force to the first pair of contact making members (120a) and the second pair of contact making members (120b).
In an embodiment of the invention, upon actuation of the operating member (108), the first fixed contact terminal (106a) abuts and slides against the first pair of contact making members (120a) and similarly second fixed contact terminal (106b) abuts and slides against the second pair of contact making members (120b). This abutment and sliding mechanism provides a rubbing action and in turn, helps in removing the oxide layer formed on the contacts due to corrosion of the contacts. This self-cleaning action ensures better operation and tends to improve the service life of the push button switching element (100).

Now referring to Figure 9, there is illustrated an exploded view of a push button switching element (200) in accordance with another embodiment of the present invention. The push button switching element (200) comprises a housing (202) which defines an open end (202a), an opposing closed end (202b) having an aperture (202c) therein, and an internal space. A base (204) is adapted to cooperate with the housing (202) thereby sealing the open end (202a) of the housing (202). Further, the push button switching element (200) comprises a pair of fixed contact terminals (206a, 206b). Furthermore, the push button switching element (200) further comprises an operating member (208) adapted to move towards the base (204) upon actuation. The operating member (208) defines a first end (208a) and a second end (208b), where in a first end (208a) is adapted to be located outside the housing (202), and a second end (208b) is adapted to be located within the internal space. Furthermore, a moving contact mechanism (210) is operably coupled to the operating member (208), and is adapted to establish an electrical path between the pair of fixed contact terminals (206a, 206b), upon actuation of the operating member (208).
In an embodiment of the invention, the push button switching element (200) comprises a first fixed contact terminal (206a) of the pair of fixed contact terminals (206a, 206b) is exposed on a top surface of the base (204) and a second fixed contact terminal (206b) of the pair of fixed contact terminals (206a, 206b) project along an inner side wall of the housing (202).
In an embodiment of the invention, a resilient member (212) is disposed so as to establish an electrical path between the first fixed contact terminal (206a) and the moving contact member (210).
In an embodiment of the invention, the moving contact member (210) defines a first wall contacting the resilient member (212). A second wall extends from the first wall which faces the inner side wall of the housing (202). Further, a contact making member disposed on the one end of the second wall.
Referring to Figure 10, which is a functional view of the push button switching element (200) in accordance with an embodiment of the present invention, showing the push button switching element (200) in OFF position which corresponds to the operating member (208) being in not actuated state.

Referring to Figure 11 which is a functional view of the push button switching element (200) in accordance with an embodiment of the present invention, showing the push button switching element (200) in ON position which corresponds to the operating member (208) being in actuated state. It can be thus noticed that upon actuation of the operating member (208), the contact making member slides and abut the second fixed contact terminal (206b) of the pair of fixed contact terminals (206a, 206b).
It has been surprisingly observed that among the various embodiments illustrated, the embodiments illustrated in Figure 2 and Figure 9 provide substantially increased life span. Also, the quality of contact making is better for these constructions.
In an embodiment of the invention, a protective member (122, 214) is linked to the operating member (108, 208) to reduce ingress of dust, dirt, water, foreign matter, grease, contamination material, etc. The protective member (122, 214) ensures an extra level of protection to the push button switching element (100, 200) from harmful environmental conditions.
Referring back to Figure 1, in an embodiment of the invention, a base plate (20) is provided to seal the casing (12) of the low current switch (10). In an embodiment of the invention, a screw (12) is used to connect base plate (20) to the casing (12) of the low current switch (10).
While specific language has been used to describe the disclosure, any limitations arising on account of the same are not intended. As would be apparent to a person in the art, various working modifications may be made to the method in order to implement the inventive concept as taught herein.
The figures and the forgoing description give examples of embodiments. Those skilled in the art will appreciate that one or more of the described elements may well be combined into a single functional element. Alternatively, certain elements may be split into multiple functional elements. Elements from one embodiment may be added to another embodiment. For example, orders of processes described herein may be changed and are not limited to the manner described herein. Moreover, the actions of any flow diagram need not be implemented in the order shown; nor do all of the acts necessarily need to be performed. Also, those acts that are not dependent on other acts may be performed in parallel with the other acts. The scope of embodiments is by no means limited by these specific examples.

Numerous variations, whether explicitly given in the specification or not, such as differences in structure, dimension, and use of material, are possible. The scope of embodiments is at least as broad as given by the following claims.

WE CLAIM:

1.A low current switch (10), comprising:
a casing (12) comprising an aperture, the casing defining a first storage space;
a push button switching element (100,200) being accommodated in the first storage space, the push button switching element (100,200) comprising an operating member;
a top cover (14) comprising an aperture; the top cover (14) enveloping the casing (12) to define a second storage space; and
a plunger (16) being located at least partly in the second storage space; the plunger (16) comprising a first end adapted to traverse via the aperture in the top cover (14) to receive an actuating force, and a second end adapted to cooperate with the operating member of the push button switching element (100, 200) to transfer said actuating force to the operating member of the push button switching element (100,200).
2. The low current switch as claimed in claim 1, wherein the plunger (16) defines a flange disposed between the first and the second end.
3. The low current switch as claimed in claim 1, wherein a resilient member (18) is disposed between the casing (12) and the flange of the plunger (16) such that the resilient member (18) is adapted to provide a restoring force to the plunger (16).
4. The low current switch as claimed in claim 1, wherein the push button switching element (100, 200) comprising:
a housing (102, 202) defining an open end (102a, 202a), an opposing closed end (102b, 202b) having an aperture (102c, 202c) therein, and an internal space;
a base (104, 204) adapted to cooperate with the housing (102, 202) thereby sealing the open end (102a, 202a) of the housing (102, 202);
a pair of fixed contact terminals (106a, 106b; 206a, 206b);
an operating member (108, 208) adapted to move towards the base (104, 204) upon actuation, the operating member (108, 208) defining a first end (108a, 208a) adapted to be located outside the housing (102, 202), and a second end (108b, 208b) adapted to be located within the internal space; and

a moving contact mechanism (110, 210) operably coupled to the operating member (108, 208), and adapted to establish an electrical path between the pair of fixed contact terminals (106a, 106b; 206a, 206b), upon actuation of the operating member (108, 208).
5. The low current switch as claimed in claim 4, wherein the push button switching element (100) further comprises a resilient member (112) disposed between the base (104) and the operating member (108) to provide a restoring force to the operating member (108).
6. The low current switch as claimed in claim 4, wherein the base (104) of the push button switching element (100) is provided with a pair of non-conductive pillars (114a,l 14b) projecting towards the opposing end (102b) of the housing (102) of the push button switching element (100).
7. The low current switch as claimed in claim 6, wherein the pair of non-conductive pillars (114a, 114b) are adapted to hold the pair of fixed contact terminals (106a, 106b) such that the pair contact of contact terminals (106a, 106b) project towards the opposing end (102b) of the housing (102).
8. The low current switch as claimed in claim 4, wherein the moving contact mechanism (110) comprises:
a plate member (116) having four corners;
four "L" shaped leg members (118) extending downward from the four corners; and
a first pair of contact making members (120a) and a second pair of contact making members (120b) formed at the ends of the four L-shaped leg members (118), such that upon actuation, the first pair of contact making members (120a) come in contact with a first fixed contact terminal (106a) and the second pair of contact making members (120b) come in contact with a second fixed contact terminal (106b).
9. The low current switch as claimed in claim 8, wherein the first pair of contact making
members (120a) project towards the opposing end (102b) of the housing (102) of the
push button switching element (100) and the second pair of contact making members

(120b) project towards the opposing end (102b) of the housing (102) of the push button switching element (100).
10. The low current switch as claimed in claim 9, wherein the first pair of contact making members (120a) converge towards each other to define a first channel of minimum distance and the second pair of contact making members (120b) converge towards each other to define a second channel of minimum distance.
11. The low current switch as claimed in claim 8, wherein upon actuation of the operating member (108), the first fixed contact terminal (106a) abuts the first pair of contact making members (120a) at the first channel and the second fixed contact terminal (106b) abuts the second pair of contact making members (120b) at the second channel.
12. The low current switch as claimed in claim 4, wherein a first fixed contact terminal (206a) of the pair of fixed contact terminals (206a, 206b) is exposed on a top surface of the base (204) and a second fixed contact terminal (206b) of the pair of fixed contact terminals (206a, 206b) project along an inner side wall of the housing (202).
13. The low current switch as claimed in claim 4, wherein a resilient member (212) is disposed so as to establish an electrical path between the first fixed contact terminal (206a) and the moving contact mechanism (210).
14. The low current switch as claimed in claim 4, wherein the moving contact mechanism (210) comprises:
a first wall contacting the resilient member (212);
a second wall extending from the first wall, the second wall facing the inner side wall
of the housing (202); and
a contact making member disposed on the one end of the second wall, such that upon
actuation, the contact making member slides and abuts the second fixed contact
terminal (206b) of the pair of fixed contact terminals (206a, 206b).

15. The low current switch as claimed in claim 4, wherein a protective member (122, 214) is provided on the operating member (108, 208) to seal/protect the operating member (108, 208).