DESC:
Field of the Invention

The present invention relates to a switch module which can be mounted on the handle bar of a vehicle or motorcycle and more particularly, to a switching mechanism for low amperage applications and which can be located inside the switch module for operating a variety of electrical systems / accessories.

Description of the Related Art

Two wheeler vehicles such as motorcycles come with a variety of electrical systems such as head light, passing beam, dipper, blinker, horn, self start etc. In all the afore-mentioned electrical systems, electrical power derived from the battery is supplied to the appropriate appliances via a switching. Currently, each of the electrical appliances is connected in series to the battery via a separate switch. Usually, one or more switches are placed on the handle bar of the motorcycle for easy access to operation. Preferably, the switches are grouped to form a right hand switching module and a left hand switching module. The handle bar switch module comprises a switching system for effecting the switching operations of electrical systems of the motorcycle.

Furthermore, the switching module and/or switch system mounted on the handlebar of the motor cycle needs to be sealed properly to avoid any provision to control entry of dust particles. In the absence of proper sealing of switching module, substantial amount of dust can get collected near or at the contacting point. Due to the above, carbon deposits are formed at the contact points, which results in the reduction in the life and reliability of the switch making the switch not suitable for low amperage applications.

Nowadays, low amperage switching assemblies are popular because these switches can be used in micro-controller based electronic systems for operating one or more of the afore-mentioned accessories. There are two categories of switching units namely contact-type switching unit and contact-less switching unit.

The contact-type switching unit includes micro-switches or sealed typed switches for low amperage application in motorcycles. However, these contact-type switches come in predefined shapes and sizes, which makes them unsuitable from customization point of view. Moreover, the sizes of these types of switches are large which makes them costly. The contact-less switching systems are also suitable for low amperage applications and can be customized easily as compared to micro-switches. However, these switches are costly.

The above-mentioned existing low amperage switching systems have the following drawbacks:
(a) reduced life cycle;
(b) high assembly and process time and cost;
(c) Complex product assembly;
(d) More number of components;
(e) existing low amperage switching systems are costly.
Therefore, there exists a need to provide a switching system for two-wheeler or motorcycle which is cost effective and can be sealed properly.

Objects of the invention

Accordingly, it is a principal object of the present invention to provide a low amperage switching system.

Another object of the present invention is to provide a handle bar switch module comprising a low amperage switching system for operating one or more electrical system or accessories of two-wheeler vehicle or motorcycle.

Still another object of the present invention is to provide a switching system having increased total life cycle.

Yet another object of present invention is to provide a switching system which involves reduced number of components.

A further object of present invention is to provide a switching system which has reduce smaller packaging size.

A further more object of the present invention is to provide a switching system which simplifies assembling of handlebar switch module.

Another object of present invention is to provide the smooth operation of the various functions in handlebar switch.

One more object of the present invention is to provide a switching system with an integrated connector.

Summary of the Invention

The present invention is directed to an switch module, which substantially obviates one or more problems due to limitations and disadvantages of the related art.

Accordingly, the present invention provides for a switch module cap housing sub assembly comprising: a cap, spring and plunger; said plunger having more than one positive lock and each lock having at least one slit to provide flexibility, while locking with said cap; top surface of said cap being used to push the switch module in vertical downward direction and the protrusion at the lower surface of the plunger helps in actuating the dome switch from the center; a housing to hold the cap-sub assembly for vertical downward motion and bear the extra load applied by the rider through the knob on the cab; terminals to pass the signal to electronic circuit which could be rigid or flexible; a conductive metal dome which acts as a floating contact and circuit is completed on pressing; and an environmental protection shield comprising of thin sheets with some adhesives to protect the contact area from external contamination.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention may be realized and attained by the structure particularly pointed out in the written description as well as in the accompanying drawings.

Brief Description of the Accompanying Drawings

The invention will be described in conjunction with the accompanying drawings, in which:

Figure 1 illustrates the support-structure with the low-amperage switching unit of low-amperage switching system in accordance with an embodiment of the present invention;

Figure 2 illustrates an exploded view of Figure 1 in accordance with an embodiment of the present invention;

Figure 3 illustrates a low-amperage switching unit of the switch in accordance with an embodiment of the present invention;

Figures 4a and 4b illustrate the exploded and assembled views respectively, of the cap-sub assembly of the switch module in accordance with an embodiment of the present invention;
Figure 5 illustrates the actuation assembly of the low-amperage switching system in accordance with an embodiment of the present invention;

Fig. 6 illustrates the exploded view of the switch module, in accordance with an embodiment of the present invention;

Fig. 7 illustrates the top view of the cap in accordance with an embodiment of the present invention;

Figures 8(a) illustrates the X-X Sectional view of the Cap sub assembly locked in the housing and Fig. 8(b) illustrates the Section Y-Y view of the Plunger locked in the Cap, in accordance with an embodiment of the present invention;

Fig. 9 illustrates the operating characteristics for the Metal Dome and Desired Operating Characteristics in accordance with an embodiment of the present invention;

Fig. 10(a) illustrates the combined operating characteristics for the Dome surface, in accordance with an embodiment of the present invention;

Fig. 10(b) illustrates the combined operating characteristics for the Cap surface, in accordance with an embodiment of the present invention;

Fig. 10(c) illustrates the combined operating characteristics for the Cap placed over Dome surface, in accordance with an embodiment of the present invention;
Fig. 10(d) illustrates the characteristic of the Load Vs Travel in a Condition where the Trip Force is greater than the Installed load, in accordance with an embodiment of the present invention;

Fig. 11(a) and 11(b) illustrate the Rocker type arrangement of the switch module, in accordance with an embodiment of the present invention;

Fig. 12(a) and 12(b) illustrate the Hinge type arrangement of the switch module, in accordance with an embodiment of the present invention.

Skilled artisans will appreciate that elements in the drawings are illustrated for simplicity and have not 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 embodiments of the present invention.

Detailed Description of the Invention

While the invention is susceptible to various modifications and alternative forms, specific embodiment thereof has been shown by way of example in the drawings and will be described in detail below. It should be understood, however that it is not intended to limit the invention to the particular forms disclosed, but on the contrary, the invention is to cover all modifications, equivalents, and alternative falling within the spirit and the scope of the invention as defined by the appended claims.

Before describing in detail the various embodiments of the present invention it may be observed that the novelty and inventive step that are in accordance with the present invention resides in the construction of switch for vehicle. It is to be noted that a person skilled in the art can be motivated from the present invention and modify the various constructions of the switch. However, such modifications should be construed within the scope and spirit of the invention.

Accordingly, the drawings are showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having benefit of the description herein.

The terms “comprises”, “comprising”, or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a setup, device that comprises a list of components does not include only those components but may include other components not expressly listed or inherent to such setup or device. In other words, one or more elements in a system or apparatus proceeded by “comprises… a” does not, without more constraints, preclude the existence of other elements or additional elements in the apparatus. The following paragraphs explain present invention with respect to a switching mechanism for low amperage applications and which can be located inside the switch module for operating a variety of electrical systems / accessories. The invention in respect of the same may be deduced accordingly.

Accordingly, it is an object of the present invention to provide a switch having low amperage switching mechanism for operating various electrical systems/accessories of a vehicle. Other objects of the present invention will be clear from the description provided herein.

Accordingly, the present invention provides a switch for a vehicle, comprising:
at least one actuating-knob;
a rigid support-structure;
a low amperage switching unit comprising:
a circuit disposed on the support structure, and comprises one or more fixed-contact;
at least one conducting dome disposed on the circuit above the each of the fixed contact; the conducting dome, when pressed, is adapted make contact with the fixed-contact thereby closing the circuit;
a mounting structure disposed on the rigid support structure, comprising:
one or more housing having a bore, and being secured to the rigid support-structure so that the dome mounted on the support-structure is accessible through the bore of the housing;
one or more actuation assembly, each comprising:
a cap comprising one or more slots,
a plunger comprising at least one positive lock configured to cooperate with the slots of the cap thereby securing the plunger with the cap;
a spring disposed between the plunger;
a cap comprising one or more positive locks for moveably securing the cap with the housing and the cap being movable, under actuation force, towards the conducting dome to actuate the plunger thereby pressing the dome to make contact with the fixed-contact.

In an embodiment of the present invention, slots are provided in the cap and locks are provided in the plunger and vice-versa arrangement is also possible.

In another embodiment of the present invention, the length of the slot is always greater than the travel of the cap with respect to the housing.

In still another embodiment of the present invention, the spring keeps the plunger in a certain installed mode.

In yet another embodiment of the present invention the space provided between the slot and the locks facilitate smooth travel between the cap and the plunger.

In a further embodiment of the present invention, the stopper restricts the upward movement of the plunger.

In another embodiment of the present invention, in the fully closed position, there is no contact between said cap and said plunger.

In still another embodiment of the present invention, each lock has at least one slit to provide flexibility, while locking with said cap.

In yet another embodiment of the present invention the circuit could be rigid or flexible.

In a further embodiment of the present invention, the conducting dome is covered by an environmental protection shield comprising of thin sheets with some adhesives to protect the contact area from external contamination.

In a further more embodiment of the present invention the flanged surface in said cap abuts at the top end of the housing and acts as a stopper to avoid transfer of excessive load on the dome surface.

Figure 1 illustrates an assembled view showing switching unit (8) disposed on the rigid support structure (9) in the switch of the present invention in accordance with an embodiment.

Figure 2 illustrates a rigid support-structure (9) and a switching unit (8) of the switch according to an embodiment of the present invention.

Referring to Figures 1 and 2, the support-structure (9) is a rigid support-structure so as to provide the rigid support to the flexible circuit (5a) of the switching unit (8). The ‘support-structure’ may be defined as a structure which is adapted to provide support to one or more components such as flexible circuit of the switching unit. In other words, the purpose of the support structure is to hold the switching unit and to provide support to the low amperage switching unit. The support-structure (9) can be insert moulded with metal terminals (6) on which input / output terminals of low amperage switching unit (5) is soldered. The support structure (9) comprises one or more mounting-arms (18) for mounting the support-structure (9) to casing of switch in case of handle-bar switch (not shown in figures) or to panel e.g. front panel (not shown in figures) of the vehicle in case of panel-switch by means of fasteners or snap locks. In an embodiment of the present invention, the support structure (9) can be optionally provided with pivots and snaps for mounting the one or more actuating knobs.

As shown in Figure 2, the switch of the present invention can be provided with an electronic control unit (ECU) (10) which can be optionally mounted on the rigid support structure (9) and operatively coupled with the output terminals of the switching unit (8).

Figure 3 illustrates a low-amperage the switching unit (8) of the switch of the present invention in accordance of an embodiment. Referring to figures 1, 2 and 3, the switching unit comprises a flexible circuit (16) comprising one or more fixed contact (19) and one or more dome (5) disposed above the said fixed contacts (19) so as form a low ampere electronic switching unit (8). The ‘flexible-circuit’ may be defined as a circuit comprising electrical connectors and fixed contacts which are printed or disposed on a flexible substrate and the one or more dome is disposed above the each fixed contact. The ‘flexible substrate’ can be a flexible film which is basically a circuit carrier on which the circuit can be printed or disposed.

The dome can be covered from top with the help of a top cover film (not shown in figure). The top-cover film is a flexible film which provides a sealing to the low amperage switch and prevent entry of external contamination such as dust, dirt and water. An insulator (not shown in figure) is interposed between the dome and the circuit. In an embodiment of the present invention, a top circuit (not shown in figure) can optionally be provided above the dome and beneath the top cover film. Referring to figure 3, the flexible-circuit is provided with at least one reference hole (RH) and a Connector footprint (CFP).

The dome (5), when pressed, gives the user a positive tactile feedback. The dome is made up of metal which is a good conductor of electrical current and life cycle of the dome can go up to 5 million-cycles. The dome can be plated either in nickel, silver, gold or any other suitable metal with highly conductive surface treatment.

The dome (5) can be of any suitable shape such as elliptical, quadrangular, circular, or triangular in construction or polygonal (not shown in figure).

Figure 4(a) illustrates the exploded view of the cap sub-assembly. The cap (1) is cylindrical in construction having a substantially flat top surface (19) and a cylindrical bottom (31) defining a hollow enclosure. The top surface (19) extends radially so as to form a peripheral flange (28). A pair of cuts outs (27) are provided opposite to each other on the flange. A pair of rectangular slots (10) are provided on the cylindrical cap (1). Snaps (26) are provided on the outer cylindrical portion of the cap surface for movably securing the cap (1). The cap (1) has a top end (29) and a bottom end portion (30). A spring (2) is adapted to be disposed inside the hollow enclosure of the cylindrical cap (1). A plunger (3) is also adapted to be disposed inside the cap sub-assembly. The plunger (3) is cylindrical in shape having a hollow top surface (42) and a covered bottom surface having a protrusion at the center. The plunger (3) has more than one positive lock (9) and each lock has at least one slit (8) to provide flexibility while locking the cap (1). The top surface (19) of the cap (1) is used to push the Switch module in the downward direction and the protrusion at the lower surface of the plunger (3) helps in actuating the dome switch from the center.

Referring again to Figures 4a, 4b and 5, the plunger (3) is locked inside the cap (1). A spring (2) is disposed in between the cap (1) and the plunger (3). The spring (2) keeps the plunger (3) in a certain installed mode. Slots (10) are provided in the cap (1) and locks (9) are provided in the plunger (3). A vice-versa arrangement is also possible. A space is provided between the slot (10) and the locks so that it can travel smoothly. The length of the slot (10) is always greater than the travel of the cap with respect to the housing (7).

A locking mechanism (26) is provided in the outer surface of the cap (1). A flange surface (28) is provided in the cap (1) which abuts at the top end of the housing and acts as a stopper to avoid transfer of excessive load on the dome surface (5).

In the fully closed position, (i.e. when the flange portion (28) of the cap (1) abuts with the top end of the housing (7)) a gap is disposed between the cap (1) and the plunger (3). In other words, in the fully closed position, there is no contact between the cap (1) and the plunger (3).

Referring to Fig. 6, an elongated cylindrical housing (7) is provided that has a top end (40) and a bottom end (45). The housing (7) is provided with a plurality of slits (43) disposed on the walls of the cylindrical housing (7) as shown in Figure 6. Each of the slits (43) partially extends from the top end toward the bottom end. The slits (43) provide flexibility to the housing (7). A pair of slots (32) is provided on the walls of the cylindrical housing (7). These slots (7) are elongated rectangular in nature which allow and accommodate the reciprocal movement of the plunger (3) in the housing (7).

The Housing Sub Assembly comprises a Housing (7) to hold the Cap Sub assembly for vertical downward motion and to bear the extra load applied by rider through Knob on Cap (1), Terminals (6) to pass the signal to electronic circuit, it could be Rigid or Flexible, Conductive Metal Dome (5) to act as a floating contact and circuit will be completed on pressing and Environmental Protected Shield comprising of thin plastic sheets with some adhesives to protect the contact area for external contamination.

Fig. 7 illustrates the top view of the cap sub-assembly. As mentioned earlier the Cap Sub Assembly comprises of the cap (1), spring (2) and plunger (3). The plunger (3) has more than one positive lock and each lock has at least one slit (8) to provide flexibility while locking with cap (1) (vice versa of locking method is also possible). The top surface of cap (1) is used to push the switch module in the vertical downward direction and the protrusion at the lower surface of the plunger (3) helps in actuating the dome switch from the center.

Figures 8(a) and 8(b) illustrate the Sectional views of the cap sub-assembly locked in the housing and plunger locked in the cap respectively, in accordance with an embodiment of the present invention. Fig. 8(a) illustrates the cap sub assembly locked in the Housing in X-X direction. The switch has been illustrated in two conditions, i.e. the OFF and ON condition. In the OFF condition the Switch Module Travel is illustrated. A clearance (16) is provided as shown, which is intentionally provided at the time of manufacturing, so that there is no extra pressure on the dome in the free condition i.e. the OFF condition. The Stopper (15) restricts the upward movement of the plunger.

When the knob is pressed it attains the ON condition thereby the cap moves down in the vertical direction. As the cap moves down, the plunger moves down and electrical contact is made.

Fig. 8(b) illustrates the Plunger locked in the Cap in Y-Y direction for the OFF and ON condition. The clearance (14) due to the flange surface (28) provided in the cap (1) results in abuting at the top end of the housing and acts as a stopper to avoid transfer of excessive load on the dome surface (5).

Fig. 9 illustrates three graphs. The first graph depicts the characteristics of the Dome switch Force Vs Travel. In the Load Vs Travel graph, when the switch is pressed, the curve rises above from zero to a maximum position signified by the Trip Force and the curve comes down as shown in the graph due to the rebounding force (y grams) of the spring at the time of releasing the switch.

Fig. 9(b) is the second graph which illustrates the Operating characteristics of the Dome Switch. When the Switch is in ON condition the Pretravel, operating position and Dead end is illustrated. Beyond the dead end, No overtravel is possible.

Fig. 9(c) is the third graph illustrates the desired operating characteristics of the Switch. Fig. 10(a) illustrates the characteristics of Dome surface. In this graph the Dome Switch force Vs Travel is shown. When the Switch is pressed, the curve rises from zero to a maximum position. Any further pressing beyond that does not increase the curve due to the presence of the stopper. This top most point is the Trip Force after which the curve comes down owing to the rebound force of the spring at the time of the release of pressure on the switch.

The operating force of a Dome Switch is 2N and a mechanical stopper is installed between the “Operating Position” and “Dead End” to have safe operation. The handlebar Switch knob operating force is too high in the order of 15N to 50N and the operating force of the Dome Switch is very less of the order of 2N. So, it is important to have an Over travel value as wide as possible. To achieve the same an additional assembly is added between, which provides the additional required travel, mechanical stopper, vertical push and center.

Figure 10 illustrates the Combined Operating characteristics for the Switch. Fig. 10(a) illustrates the characteristics of the Dome surface. When the knob is pressed, the curve rises from a zero value to a maximum position beyond which it does not increase due to the provision of the flange surface provided on the cap which abuts at the top end of the housing acting as a stopper thus avoiding transfer of excessive load on the dome surface. This top most point reached is the Trip force after which the curve comes down owing to the rebound force of the spring, as the cap returns to its original position due to the action of the spring.

Fig. 10 (b) illustrates the characteristics of the cap surface i.e. the graph of Cap sub assembly force Vs Travel. As the switch is pressed the Installed force for the spring increases and reaches a maximum point shown by “x” and during the rebound the same is shown by “y”, where the force returns back to a minimum return position. “z” shows the mean value between “x” and “y”.

The Sum of the Dome Surface Characteristic and the Cap surface characteristic is illustrated by a third graph as shown in Figure 10(c) which denotes the characteristic when the cap is placed over the dome. This graph illustrates the condition when the trip force is less than the Installed load.

Fig. 10(d) illustrates the Condition when the trip force is greater than the Installed load. In this graph the free travel of the plunger, the difference between the installed load and the trip force is illustrated.

Figures 11(a), (b) and 12 (a) and (b) illustrate various constructions of the knob mechanism that can be provided in the switch. Figure 11(a), 11(b) and 12(a) and (b) illustrate knob with Rocker type and Hinge type mechanism, respectively. Referring to figures 11(a)-(b), exterior portion of the knob is accessible to the rider of the vehicle to apply actuation force to actuate the knob from the OFF position to at least one ON position. Interior portion of the knob is formed so that actuation of the knob from the OFF position to at least one ON position actuates the cap (1) towards the switching unit or the dome thereby transmitting the actuating force to the dome (16) pressing the same to make contact with the fixed contact.

As can be clearly understood, in the switch of the present invention the actuation force on the dome (16) is applied at the center or at location which is proximal to the center of the dome which results is proper and effective switching operation and also increases life cycle of the dome.

Advantages of the Present Invention

The main advantage of the present invention is to provide a low amperage switching system which has the ability to operate one or more electrical system or accessories of two-wheeler vehicle. The switching system of the present invention provides a superior life cycle with less number of components and reduced packaging size. Another advantage of present invention is to provide the smooth operation of the various functions in handlebar switch with an integrated connector.

The advantages of the disclosed invention are thus attained in an economical, practical, and facile manner. While preferred aspects and example configurations have been shown and described, it is to be understood that various further modifications and additional configurations will be apparent to those skilled in the art. It is intended that the specific embodiments and configurations herein disclosed are illustrative of the preferred nature and best mode of practicing the invention, and should not be interpreted as limitations on the scope of the invention.
,CLAIMS:

1. A switch for a vehicle, comprising:
at least one actuating-knob;
a rigid support-structure;
a low amperage switching unit comprising:
a circuit disposed on the support structure, and comprises one or more fixed-contact;
at least one conducting dome disposed on the circuit above the each of the fixed contact; the conducting dome, when pressed, is adapted make contact with the fixed-contact thereby closing the circuit;
a mounting structure disposed on the rigid support structure, comprising:
one or more housing having a bore, and being secured to the rigid support-structure so that the dome mounted on the support-structure is accessible through the bore of the housing;
one or more actuation assembly, each comprising:
a cap comprising one or more slots,
a plunger comprising at least one positive lock configured to cooperate with the slots of the cap thereby securing the plunger with the cap;
a spring disposed between the plunger;
a cap comprising one or more positive locks for moveably securing the cap with the housing and the cap being movable, under actuation force, towards the conducting dome to actuate the plunger thereby pressing the dome to make contact with the fixed-contact.

2. The switch module as claimed in claim 1, wherein slots are provided in the cap and locks are provided in the plunger and vice-versa arrangement is also possible.

3. The switch module as claimed in claim 1, wherein the length of the slot is always greater than the travel of the cap with respect to the housing.

4. The switch module as claimed in claim 1, wherein the spring keeps the plunger in a certain installed mode.

5. The switch module as claimed in claim 1, wherein the space provided between the slot and the locks facilitate smooth travel between the cap and the plunger.

6. The switch module cap as claimed in claim 1, wherein the stopper restricts the upward movement of the plunger.

7. The switch module as claimed in claim 1, wherein in the fully closed position, there is no contact between said cap and said plunger.

8. The switch module as claimed in claim 1, wherein each lock has at least one slit to provide flexibility, while locking with said cap.

9. The switch module as claimed in claim 1, wherein the circuit could be rigid or flexible.

10. The switch module as claimed in claim 1, wherein the conducting dome is covered by an environmental protection shield comprising of thin sheets with some adhesives to protect the contact area from external contamination.

11. The switch module as claimed in claim 1, wherein the flanged surface in said cap abuts at the top end of the housing and acts as a stopper to avoid transfer of excessive load on the dome surface.