Field of the invention
The present invention generally relates to Low Amperage control switches and in-particular relates to Tact/Micro switches.

Background of the invention

Miniature snap-action switch or micro switches are known for operating the various functions. In an example, such functions relate to vehicle and include blinkers, cruise control, etc. Conventionally, as shown in Fig. 1, such control switches have a plunger (1) to be actuated by an external actuating force. The plunger (1) is coupled with a moving contact (3) loaded by means of a spring (5). A plurality of terminals (T1, T2) is disposed in the interior of the control switch by means of base (6) made from a non-conductive material such that the base (6) provides insulation between the terminals (T1, T2). When a user actuates the plunger (1), the moving contact (3) moves towards the terminals (T1, T2) energizing the spring (5). The moving contact (3) thereby, establishes contact between the terminals (T1, T2) to complete the electric circuit resulting in an electric signal to achieve a desired function. When the user releases the actuating force from the plunger (1), due to resilient action of spring (5), the moving contact (3) moves to the unactuated position, and the contact between terminals (T1, T2) breaks. The upward movement of the moving contact (3) is restricted by the body (4).

A drawback associated with aforesaid switch is current leakage due to entry of water between terminals. Water leakage into the switch further results in corrosion of the terminals and base. This in turn reduces the lifecycle efficiency of the switch.

While conventional switches recently have been improved to address aforesaid loophole, fact remains that conventional micro-switches in handlebar assembly lag behind in terms of offering any feedback (e.g. auditory/haptic feedback) with respect to user-actuation of switches. Moreover, the overall switching apparatus and assembly is found to be complex when compared with the compactness associated with the micro-switches.

Accordingly, there lies a need for a micro-switch that is IP67 complied, water proof, compact in size whereby the contact making/breaking is discrete and can be fitted with minimal occupancy of space.

There lies at-least a need of switch that can withstand ‘G Levels’ as per 2 way switch conditions, and can be used “with and without PCB”.

Further, there lies a need for a micro-switch that has a flexibility to adopt different type mechanism as Push type, Hinge type and sea-saw type etc.

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 present disclosure. This summary is not intended to identify key or essential inventive concepts of the claimed subject matter, nor is it intended for determining the scope of the claimed subject matter.

One or more drawbacks of conventional control switches as described in the prior art are overcome and additional advantages are provided by the low amperage control switch for vehicles as claimed in the present disclosure. Additional features and advantages are realized through the technicalities of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered to be a part of the claimed disclosure.

In an embodiment, the present subject matter’s tactile or micro switch comprises a first-housing defining a hollow interior region there-between and comprising a through-bore. An assembly of a protruding knob supported over a resilient-membrane is accommodated within the hollow region, such that the protruding knob is allowed to protrude outside the first-housing via the through-bore. An electrically conductive dome is supported beneath the resilient-membrane and movable vertically along the protruding knob. A plurality of electrically-conductive terminals are supported within a second housing and define at-least one of: a) an electrically open-state as a default state; and b) an electrically closed state based on connection with the vertically moving dome.

In one non-limiting embodiment of the present disclosure, there is provided a low amperage control switch for vehicles. The said control switch comprises a housing being configured with a cover to define a hollow interior region there-between. A rubber-membrane comprising a proximal end being disposed in the interior region of the housing, and a distal end emerging externally from the interior region through an opening in the cover. The distal end itself is covered by a plunger at the top such that the plunger protrudes through the opening of the cover.
The distal end is adapted to be pressed through the opening in a longitudinal direction to actuate at least one contact switch. A contact switch or a dome is disposed in an encapsulation formed by the proximal end of the rubber-membrane within the hollow interior region. In an embodiment of the present disclosure, the contact-switch comprises a moving contact or dome that contacts a pair of terminals provided within the housing. The terminals are configured with an electrical circuit of the vehicle.

In a further embodiment of the present disclosure, the dome is movably supported in the encapsulation formed by the proximal end of the rubber membrane.

In a still further embodiment of the present disclosure, the rubber membrane comprises an actuating face; the actuating face being configured to actuate the dome or moving contact of the control switch.

In another embodiment of the present disclosure, the distal end of the actuation membrane has a generally dome shape and is used to mount the plunger

Overall, the present subject matter relates to Tact/micro switch including/ excluding wired or installation over PCB board or any housing for any type of micro-switch (e.g. 2W/3W/4W). In an example, the micro-switch may be implemented on the handlebar/dashboard/panel assembly. The present micro-switch incorporates water and dust-protection provisions. The micro-switch as rendered by the present subject matter at least renders a universal sealed Tact/micro switch, which is suitable for all type mechanism as Push type, Hinge type and sea-saw type etc. The present tact switch assembly has a mechanism that involves combination of a base assembly, cover, rubber membrane plunger and thereby achieves discrete contact making/breaking by means of a dome shaped moving contact.

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 drawings
These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:

Fig. 1 illustrates a prior art micro switch;
Fig. 2 illustrates an exploded-view of the control switch, in accordance with an embodiment of the present subject matter;
Fig. 3 another exploded view of the control switch of Fig. 2, in accordance with an embodiment of the present subject matter;
Fig. 4 illustrates the terminals within the base assembly or housing, in accordance with an embodiment of the present subject matter;
Fig. 5 illustrates example mechanisms of assembling the top cover with the housing, in accordance with an embodiment of the present subject matter;
Fig. 6 illustrates a low amperage control switch such as a micro/tact switch, in accordance with an embodiment of the present subject matter;
Fig. 7 illustrates a micro/tact switch, according to another embodiment of the present subject matter; and
Fig. 8 illustrates another micro/tact switch according to yet another embodiment of the present subject matter.

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 flow charts illustrate the method in terms of the most prominent steps involved to help to improve understanding of aspects of the present invention. Furthermore, in terms of the construction of the device, one or more components of the device 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
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 system, 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.

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 nonexclusive inclusion, such that a process or method 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 subsystems 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.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The system, methods, and examples provided herein are illustrative only and not intended to be limiting.

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. The figures are for the purpose of illustration only and should not be construed as limitations on the assembly and mechanism of the present disclosure. Reference will now be made to a low amperage control switch which is explained with the help of figures.
It is understood by a person skilled in art that the low amperage control switch, as disclosed in the present disclosure, can be mounted at different locations on the front panel of a vehicle in horizontal or vertical position or any other position as per the suitability of the manufacturer/user.

Figure 2 illustrates an exploded-view of the control switch 200. As shown in Fig. 2a, the low amperage control switch comprises a base assembly 210 made from a sturdy-material for securing the various components/sub-assemblies of the present control switch 200. The base assembly 210 comprises insert-molded terminals 212 therein.

Further, the base assembly 210 or the housing comprises an open-top side for receiving a cover 202 or a first part of housing or first housing 202. Accordingly, the base-assembly 210 may be referred as a second part of housing or second-housing 210. The first housing 202 or cover is adapted to be secured with the top side of the housing 210 so as to define a hollow-interior region there-between. The first housing 202 defines a hollow interior region there-between and comprising a through-bore. The second-housing 210 comprises holes (not shown) for receiving wires of the electrical circuit of the vehicle. A plurality of electrically-conductive terminals are supported within the second-housing 210 and define at-least one of:
a) an electrically open-state as a default state; and
b) an electrically closed state based on connection with a moving contact or a plunger (as later depicted in figures).

The control switch 200 further comprises a rubber-membrane 206 as a resilient- membrane supported in the defined hollow interior region of the housing 210. The membrane 206 comprises a proximal end and a distal-end. In the mounted condition, the proximal-end is located in the defined interior-region of the housing 210 and has a generally-rectangular construction comprising a plurality of side walls and a top-wall so as to define an encapsulation with the housing 210 in the mounted-condition. Overall, the first housing 202 and the resilient membrane 206 follow the shape of the protruding knob 204 for rigidly supporting the protruding knob 204.

The distal-end of the membrane 206 is formed longitudinally and extending away from the proximal end. In the mounted condition, the distal end emerges outwards from the interior region through a through bore (as shown in Fig. 4) in the cover 202 to thereby hold the protruding knob 204. The distal-end is dome-shaped and is used to mount a plunger 204 or a protruding knob 204. Specifically, the distal-end of the rubber membrane (206) holds the protruding knob (204) at the top to facilitate the protruding knob (204) protrude outside the first housing (202) through the through-bore.

In other words, the resilient membrane 206 comprises a first receptacle at the center to hold the protruding knob 204 at the top and a second receptacle located at the opposite side to circumferentially hold the dome 208. Accordingly, the distal-end of the rubber membrane 206 holds the protruding knob 204 at the top to facilitate the protruding knob 204 protrude outside the first housing 202 through the through-bore.

More specifically, an assembly of the protruding-knob 204 is supported over the rubber membrane 206 or the resilient-membrane 206. Such assembly is accommodated from the top within the hollow region of the cover 202 or the first housing 202 by allowing the protruding knob 204 to protrude outside the first-housing 202 via the through-bore or the recess.

In accordance with an embodiment of the present-disclosure, the distal-end of the membrane 206 is located above an actuating face of the rubber membrane 206 such that the actuating face is pressed in a downward- direction when the distal-end is pressed vertically-downwards through the recess or through-bore to actuate at-least one contact-switch 208 or the dome disposed in the defined interior region. Such a moving contact-switch 208 or dome 208 is disposed or held in the encapsulation formed by the proximal end of the rubber membrane 206, thereby preventing external contaminants such as dust and water from the reaching the dome 208. As may be understood, the electrically-conductive dome 208 is supported beneath the resilient-membrane 206 and is compressible (i.e. bulges downwards) by a downward push of the protruding knob 204 or the plunger 204.

Moreover, the process of actuating the rubber membrane 206 to execute the dome 208 bulge downwards offers a haptic feedback to the user such that such feedback is rendered only upon application of a certain amount of force that causes the rubber membrane 206 to be pressed and the dome 208 to in turn bulge downwards. Any force lesser than the requisite force renders feeble or no feedback to the user and accordingly does not lead to any switching action.

The contact switch 208 forms of a part the electrical circuit of the vehicle, such that the electrical circuit is turn implemented by means of wires, cables or the like to connect with rest of electronics/electrical components in the vehicle. In a non-limiting embodiment of the present disclosure, the contact switch 208 comprises a moving-contact or dome 208. The terminals 212 as insert-molded within the housing 210 are disposed in the encapsulation (which also houses the proximal end of the membrane 206) and accordingly comprise a plurality of contact points say Terminals 1/2. The moving -contact or dome 208 is correspondingly located over the plurality of contact points of terminals. Further, wires/connection means are soldered to the contact terminals to configure with the electrical circuit of the vehicle.

The moving contact or dome 208 is made from a conductive material and has a generally arcuate shape comprising a central portion having a curvature towards the actuating face of the membrane with respect to the sides. When the user applies activating force on the distal-end of the rubber membrane 206 by pressing in the downward direction, the actuating face of the membrane 206 applies a force on the central portion of the dome 208. The force applied by the activating face results in the central portion of the dome 208 bulging towards the terminals 212 of the housing 210 to establish electric contact between the terminals 212, thereby completing the electric circuit of the control switch 200 causing activation of an electrical signal.

Specifically, the distal-end of the membrane 206 is adapted to be pressed through the opening in a longitudinal-direction to actuate the dome 208. The dome 208 is disposed in an encapsulation formed by the proximal end of the rubber-membrane 206. The dome 208, which is supported within the encapsulation formed by the proximal end of the rubber membrane 206, is adapted to bulge vertically downwards upon having been pushed by a compression of the rubber membrane 206 as triggered by the vertical motion of the protruding knob 204. As the dome 208 is a circular-diaphragm based moving contact, it is configured to bulge vertically downwards for contacting the plurality of terminals 212 provided within the second housing for completing an electrical circuit.

Upon removal of the activating force from the distal end of the membrane 206, the distal end, experiences-resilience and is restored from the compressed state to the unactuated or flat condition. Correspondingly, the central-portion of the moving contact or dome 208 regains the arcuate shape or upwards bulging state (i.e. the default state), thereby discretely breaking contact with contact points of the terminals 212 to deactivate the electrical-signal and complete a switching cycle.

Further, Fig. 2b depicts the exploded switch-assembly of Fig. 2a with dimensional variations as compared to Fig. 2a. In an example, Fig. 2b illustrates a further compact-version of the switch assembly as depicted in Fig. 2a.

Figure 3 illustrates another exploded-view of the control switch 200 of Fig. 2. More specifically, the present micro/tact switch 200 is implementable with or without wired connection. Overall, as has been depicted aforesaid and now depicted with respect to Fig. 3a and Fig. 3b, the present micro/switch may be resolved at least into following components:
a) Plunger 204: Dome shape provided to operate from top and side.
b) Cover 202: Four drain holes provided an opposite direction to easily drain out water and dust. Moreover, the boundary is rendered suitable for ultra-sonic welding with base assembly.
c) Rubber membrane 206: It provides unique-shape for dome-centre pressing and an angular-shape provided to keep plunger 204 towards top at initial condition or the default position.
d) Dome 208: The dome is provided for contact making and breaking between terminals 212.
e) Base assembly 210: The base houses insert-molded terminals 212. The terminals 212 are circularly shaped, oriented at different altitudes, and accordingly lead to formation of enclosure or groove to facilitate as ease of dome 208 deformation (or downward-bulging of the dome 208) for making/breaking the electrical circuit/contact.

Further, Fig. 3c and Fig. 3e depicts the exploded switch-assembly of Fig. 3a and Fig. 3b, respectively, with dimensional variations as compared to Fig. 3a and Fig. 3b. In an example, Fig. 3c and Fig. 3e illustrate a further compact version of the switch assembly as depicted in Fig. 3a and Fig. 3b. Further, Fig. 3d illustrates a sectional view with respect to Fig. 3.

Figure 4a illustrates the terminals (terminals 1 and 2) that are used for getting insert-molded within the base assembly or housing 210. Fig. 4c illustrates the insert molded terminals (1 and 2) within the housing 210. A default-state of terminals 212 corresponds to normally open switch configuration of the apparatus. Further, Fig. 4b and Fig.4d depicts a variant with respect to the terminals Fig. 4a and Fig. 4c, respectively, such that the Fig. 4b and Fig.4d depicts a provision of insulation.

Figure 5a illustrates an example mechanism (Option 1) of assembling the top cover 202 with the housing 210. As shown, the housing 210 may be already provided with the rubber membrane 206 at the top, such that that rubber membrane 206 may be further provided with the plunger at its distal end. The dome switch 208 is provided between the rubber membrane 206 and housing 210. Once such unit or combination has been created, the cover may be instantiated atop the housing such that the plunger 204 protrudes through recess of the cover 202. Thereafter, the edges of the cover 202 and the housing 210 may be welded by ultrasonic welding.
Figure 5b illustrates another example mechanism (Option 2) of assembling the top cover 202 with the housing 210. As shown, the top cover 202, the plunger 204, the rubber membrane 206, the dome switch 208 may be assembled as a unit. Such unit is thereafter inverted to position the lower surface of rubber membrane 206 and dome switch 208 at the top, with the cover 202 now acting as base 210. Thereafter, the housing 210 or base assembly 210 is also inverted, such that edges of the base assembly 210 and the cover 202 are now ultrasonically welded to each other.

Figure 6 (a till c) illustrates a low amperage control switch 200 such as a micro/tact switch, in accordance with an embodiment of the present subject matter. Fig. 6a represents an isometric view of the control switch 200. As shown in Fig. 6b (sectional view with respect to Fig. 2a), said control switch 200 comprises a housing (or a base-assembly 210) being configured with a cover 202 to define a hollow interior region there-between. While the cover 202 is ultrasonically-welded to the housing 210, the terminals 212 are insert-molded within the base-assembly 210. Fig. 6c represents a bottom-view with respect to Fig. 6a, thereby representing epoxy-filling from bottom-side.

Figure 7 illustrates a micro/tact switch 200, according to another embodiment of the present subject matter. As shown in present figure, the ‘L’ shaped terminal 1 and ‘L’- shaped terminal 2 may be provided (instead of ‘straight-terminals’ in preceding figures) to facilitate a direct assembly/soldering of the micro/tact switch 200 at the PCB board.

Figure 8 illustrates a micro/tact switch according to yet another embodiment of the present subject matter. As shown in present figure 8, ‘Wire 1’ and ‘Wire 2’ are soldered at terminals (e.g. Terminal 1 & Terminal 2, or L terminal 1 and L terminal 2). Thereafter, the terminals 212 are filled through epoxy/molding for the purposes of closely sealing the wire-ends. This at least enables an ease of usage of the micro/tact switch 200 in various mechanism/modules such as Hinge type, sea-saw type, push-type etc.

Overall, by virtue of the aforesaid features, the present advantages of present micro/tact switch are provided below.

1. Design has a flexibility to adopt different type mechanism as Push type, Hinge type and sea-saw type etc.
2. The present switch assembly exhibits a compact size and easily fixable.
3. The present switch may be used with and without PCB.
4. Plunger is providing flexibility to operate top or side pressing.
5. Drain hole provided to wipe out water and dust contamination.
6. Between two terminals provide groove to facilitate an ease dome deformation for making and breaking contact.
7. The present micro-switch refers provision for haptic feedback to the user upon actuation.

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 the 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 the embodiments is at least as broad as given by the following claims.

WE CLAIM:
1. A tactile electrical-switch apparatus (200), comprising:
a first housing (202) defining a hollow interior region there-between and comprising a through-bore;
an assembly of a protruding knob (204) supported over a resilient-membrane (206), said assembly accommodated within the hollow interior region while allowing the protruding knob (204) to protrude outside the first-housing (202) via the through-bore;
an electrically conductive dome (208) supported beneath the resilient-membrane (206) and movable along the protruding knob (204); and
a plurality of electrically-conductive terminals (212) supported within a second housing (210) and defining at least one of:
a) an electrically open-state as a default state; and
b) an electrically closed state based on connection with the moving dome.

2. The apparatus (200) of claim 1, wherein the default state of terminals (212) corresponds to normally open switch configuration of the apparatus.

3. The apparatus (200) of claim 1, wherein the first housing (202) and the resilient membrane (206) follow the shape of the protruding knob (204) for rigidly supporting the protruding knob (204).

4. The apparatus (200) of claim 1, wherein the resilient membrane (206) is a rubber-membrane (206) having a proximal-end being disposed in the interior region of the second housing (210), and a distal end emerging outwards from the interior region through the through-bore in the first housing (202) to thereby hold the protruding knob (204).

5. The apparatus (200) of claim 4, wherein the distal-end of the rubber membrane (206) holds the protruding knob (204) at the top to facilitate the protruding knob (204) protrude outside the first housing (202) through the through-bore.

6. The apparatus of claim 4, wherein the distal-end of the membrane (206) is adapted to be pressed through the opening in a longitudinal-direction to actuate the dome (208), said dome(208) being disposed in an encapsulation formed by the proximal end of the rubber-membrane (206).

7. The apparatus of claim 1, wherein the dome (208) is supported within the encapsulation formed by the proximal end of the rubber membrane (206) and configured to bulge vertically downwards upon having been pushed by a compression of the rubber membrane (206) as triggered by the vertical motion of the protruding knob (204).

8. The apparatus of claim 1, wherein the dome (208) is a circular-diaphragm based moving contact configured to bulge vertically downwards for contacting the plurality of terminals (212) provided within the second housing for completing an electrical circuit.

9. The apparatus of claim 1, wherein the resilient membrane (206) comprises a first receptacle at the center to hold the protruding knob (204) and a second receptacle located at the opposite side to circumferentially hold the dome (208).

10. The apparatus of claim 1, wherein the plurality of terminals (212) are insert-molded within the second housing (210), and wherein the first-housing (202) and the second-housing (212) are ultrasonically welded to each other