Field of the Invention:
The present invention relates to a rockable seesaw type switch for use in a two wheeled vehicle that defines a forward position, a middle position and a downward position, wherein a knob of the switch can be parked in the forward position and the middle position, but cannot be parked in the downward position and the knob automatically returns from the downward position to the middle position, after release of an actuating force.
Background of the Invention:
Generally, a rockable seesaw type switch is used in a two-wheeled vehicle as a dimmer switch and the same can be allocated in a switch casing attached near a grip in a handle bar.
The dimmer switch usually has a switch knob of a rockable seesaw type. If a driver brings the dimmer switch knob to a low beam position, the head light glows in a low beam state. On the other hand, if the driver brings the dimmer switch knob to a high beam position, the head light glows in a high beam state. After the driver has brought the knob to the low beam position and stops applying the actuating force, the knob stays at the low beam position and does not automatically change the position. Thus, it can be said that the knob gets parked at the low beam position. Similar is the case when the driver brings the knob to the high beam position and stops applying the actuating force i.e., the knob stays at the high beam position and does not automatically change the position. Thus, it can be said that a conventional dimmer switch defines two positions, a high beam position and a low beam position, wherein the knob gets parked at both of the positions. Conventionally, there is provided a separate push type pass switch for realising a head light pass indicative function. The headlight operates in the pass indicative state only till the time the push button is pressed. Reference may be made to US Patent No. 4,847,454 which discloses such a conventional dimmer switch and a separate pass switch. In the conventional system described above, two separate switches are used for realizing Dipper function and Pass function. Thus, the Number of components and packing size are more due to two separate switches. Also, the conventional switches are more prone to water exposure, dust and contamination direct entry.
In the recent past, the industry has moved to integrating the dimmer switch and the pass indicative switch. Japanese Patent No. 4558606 (corresponding to Japanese Patent Application Publication No. 2007-052989), teaches an integrated dimmer and pass indicative switch. The said switch is provided with a switch knob which exhibits rocking movement between a forward position, a middle position and a downward position. In the forward

position, the head light is operated in the high beam state, while in the middle position the headlight is operated in the low beam state and in the downward position, the headlight is operated to realize the pass function. The switch knob can be parked in the forward position and the middle position, but cannot be parked in the downward position. Thus, at the time of passing operation, if the actuating force ceases to exist (for example, if the driver lifts his finger), the construction of the switch is such that the knob is automatically returned to the middle position. To attain this automatic restoration of the knob from the downward position to the middle position, the switch is provided with a torsion coil spring (or restoration spring) which is connected to the knob.
However, such a switch has needed improvement in its constitution and arrangement so as to make the same more economical, easy to manufacture and at the same time, its operability is reasonably improved from a standpoint of human engineering or ergonomics.
Object of the Invention:
In the light of these circumstances, and need for improvement, it is an object of the present invention to provide an improved switch that defines a forward position, a middle position and a downward position, wherein a knob of the switch can be parked in the forward position and the middle position, but cannot be parked in the downward position and the knob automatically returns from the downward position to the middle position after release of an actuating force.
Summary of the Invention:
Accordingly, the present invention provides a rockable seesaw type switch defining a forward position, a middle position and a downward position for use in a two wheeled vehicle, said switch comprising a housing (1); a rigid base plate (22), said rigid base plate being engageable with the housing (1) to define a pivot axis; a hand actuateable knob (10) accommodating a moving contact on a lateral side and a plunger-spring mechanism protruding outwardly from an underside, said hand actuateable knob being sandwiched between the rigid base plate (22) and the housing (1) such that it exhibits pivotal movement with respect to the pivot axis; plurality of fixed contacts that engage with the moving contact; and an inner surface of the housing (1) is provided with a detent profile (8), the said detent profile co-operating with the plunger-spring mechanism to generate restoration force to automatically restore the knob from the downward position to the middle position after release of an actuating force.

In an embodiment of the present invention, the switch functions as a toggle switch between the forward position and the middle position and the switch functions as a push button switch between the middle position and the downward position.
In another embodiment of the present invention, the housing comprises a pivot supporting wall (2) formed with a pivot shaft (6); opposite walls (7a, 7b) located adjacent to pivot supporting wall (2); and bottom wall (3) joined to the said pivot supporting wall (2) and the said opposite walls (7a, 7b).
In yet another embodiment of the present invention, the bottom wall is formed with the detent profile.
In still another embodiment of the present invention, one or more wall selected from the group comprising of the pivot supporting wall, the opposite walls or the bottom wall is provided with drainage slot (9) for water and other contamination drainage.
In one more embodiment of the present invention, the detent profile (8) comprises first, second and third areas co-joined in a sequential manner.
In a further embodiment of the present invention, the first area is in the form of locking groove for allowing the plunger (or the ball) of the plunger-spring mechanism to be parked therein.
In a further more embodiment of the present invention, the second area is in the form of locking groove for allowing the plunger (or the ball) of the plunger-spring mechanism to be parked therein.
In another embodiment of the present invention, the third area is formed as slanting (or sloping) surface.
In yet another embodiment of the present invention, an angle of slope of the slanting surface is in the range of 20 to 45 degree, preferably in the range of 25 to 40 degree and more preferably in the range of 30 to 35 degree.
In still another embodiment of the present invention, the rigid base plate (22) is formed with a pivot shaft.

In a further embodiment of the present invention, the plurality of fixed contacts comprise of one input terminal and three output terminals, with a pair of adjacently located output terminals being electrically shorted.
In a further more embodiment of the present invention, the moving contact comprises a triangular metallic strip with three dome shape contacting points, a first dome contacting point acting as an input terminal and a second and a third dome contacting points acting as output terminals.
Brief Description of the Accompanying Drawings:
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(a) illustrates the knob carrying moving contact on the carrier along with the housing;
Figure 1(b) illustrates the knob carrying moving contact on the carrier;
Figure 2(a) illustrates a top view of the housing alone according to an embodiment of the
present invention;
Figure 2(b) illustrates a perspective view of the housing alone according to an embodiment of
the present invention;
Figure 3 illustrates a sectional view of the knob along with the housing according to an
embodiment of the present invention;
Figure 4 illustrates the moving contact plate according to an embodiment of the present
invention;
Figure 5 illustrates the base plate according to an embodiment of the present invention;
Figure 6 illustrates movement of the moving contact on the base plate according to an
embodiment of the present invention; and
Figure 7 illustrates an exploded view of the switch 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.
Description of the Invention:
Before describing in detail embodiments that are in accordance with the present invention, it should be observed that the device has been represented where appropriate by conventional symbols in the drawings, 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 process, 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, method. Similarly, 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 system or apparatus.
Although, the invention is hereinafter described in detail with reference to a dimmer cum pass type switch which is used in a two wheeled vehicle, it may be noted that the claims of the invention are not intended to be limited to such a particular type of switch and can be used in other places wherein the switch is required to define a forward position, a middle position and a downward position, and wherein a knob of the switch can be parked in the forward position and the middle position, but cannot be parked in the downward position and the knob automatically returns from the downward position to the middle position after release of an actuating force.
Referring to Figure 7, which is the exploded view of the switch of the present invention, it can be observed that the switch comprises a housing (1); a rigid base plate (22) engageable with the housing (1), the rigid base plate (22) together with the housing (1) defining a pivot axis; a hand actuateable knob (10) sandwiched between the rigid base plate (22) and the housing (1) such that it exhibits pivotal movement with respect to the pivot axis; an inner surface (32) of the rigid base plate (22) is provided with one input terminal (23) and a plurality of output terminals (24, 25, 26) (the said input terminal 23 along with the output terminals 24, 25 and 26 together being referred to as fixed contacts); and the knob (10) is

formed with a carrier (11), a lateral side (33) of said carrier (11) being configured to carry moving contact (16) which is constantly in contact with the input terminal (23) and at least one output terminal.
In another embodiment of the present invention, from an underside of the carrier (11) a spring (12) and ball or plunger (13) protrudes outwardly. The spring along with the ball or alternatively, the spring along with the plunger is referred to as spring-plunger mechanism.
In still another embodiment of the present invention, the lateral side (33) of the carrier (11) comprises a recess (35) for accommodating the moving contact (16), means (36) for latching the moving contact (16) in the said recess (35) and a biasing means (15) being sandwiched between an inner wall of the recess (35) and the moving contact (16) for exerting a positive outward pressure on the moving contact (16).
In one more embodiment of the present invention, the moving contact (16) comprises a triangular metallic strip with three dome shape contacting points, a first dome contacting point acting as an input terminal and a second and a third dome contacting points acting as output terminals. Particularly, the triangular metallic strip comprises dome shape contacting point on each corner, a first dome i.e. input dome (17) of the said dome contacting point being adjacent to the pivot axis and being constantly in contact with the input terminal (23) and the remaining two domes i.e. first output and second output domes (18a, 18b) of the dome contacting points being located away from the pivot axis and being in contact with the output terminals (24, 25, 26).
In one another embodiment of the present invention, the distance between the input dome (17) and the first output dome (18a) contacting points is greater than the distance between the first output dome (18a) and the second output dome (18b) contacting points which is greater than the distance between the input dome (17) and the second output dome (18b) contacting points. In yet another alternative embodiment, the triangular metallic strip can be in the form various other forms such as, for example, the one disclosed in Japanese Patent No. 4558606 or an equilateral triangular or an isosceles triangle.
Although, various other options are also available (such as, for example, the one disclosed in Japanese Patent No. 4558606), in one embodiment of the present invention, an edge joining the first output dome (18a) and the second output dome (18b) is in the form of an inwardly

curving arc (19). Although it may is preferable to have the edge joining the first output dome (18a) and the second output dome (18b) is in the form of an inwardly curving arc, it is not mandatory.
In a further more embodiment of the present invention, the rigid base plate (22) is provided with three output terminals, with a pair of adjacently located output terminals being electrically shorted on an external surface (31) of the rigid base plate (22).
In another embodiment of the present invention, the switch defines a first, a second and a third knob (10) location positions.
In yet another embodiment of the present invention, between the first and the second positions, the switch functions as a toggle switch while between the second and the third positions, the switch functions as a push button switch.
Referring to figures 2(a) and 2(b), it can be observed that the housing comprises:
a) a pivot shaft (6) integrated in the housing (1);
b) a pivot supporting wall (2) controls the knob (10) angular movement and provides protection against ingress of water and other contaminates;
c) a detent profile (8) located inner side of the housing (1);
d) opposite walls (7a, 7b) located adjacent to pivot supporting wall (2), said opposite walls (7a, 7b) are joined together by bottom wall (3) from bottom side for protection against water and other contamination entry from bottom side as well as from sides of the housing (1);
e) a drain slot (9) on the bottom wall (3) for water and other contamination drainage; and
f) plurality of slots (5) and an open cavity (4) are provided over bottom wall (3) for mounting of a rigid contact base sub assembly (22).
Referring to figure 1(a), the pivot shaft (6) of the housing (1) is inserted into the knob (10) at pivot point (14) in such a way that the knob (10) can swing about the pivot point (14). The detent profile (8) is provided at the inner side of the housing and is integrated with the bottom wall at an edge adjacent the pivot supporting wall (2). The detent profile (8) comprises at least two locking grooves i.e. first locking groove (8a) and second locking groove (8b) and a sloping surface (8c) at the one end of detent profile (8) (as shown in figure 2a). Further, the

plurality of slots (5) and the open cavity (4) are provided on the bottom wall (3) so as to lock the locking legs (27) of the rigid base (22).
Referring to Figure 5, it can be observed that the rigid contact base sub assembly (22) comprises:
a) a pivot shaft (29) integrated with the rigid base (22) that co-operates with the pivot point (14) provided in the knob (10);
b) rigid contacts housing slots (23, 24, 25, 26) provided over base at fixed location with respect to moving contacts (16);
c) input contact (23) provided over rigid contact base (22) towards pivot shaft (6);
d) output contacts (24, 25, 26) are provided over rigid contact base (22) radially away from input contact (23).
The rigid base (22) has an inner flat surface (32) facing moving contact (16), as shown in figure 6, while the outer surface (31) of the rigid base (22) has several compartments (37) separated by separating walls (28) moulded along with rigid base (22). The end edge of the rigid base (22) is provided with plurality of locking legs (27). The locking legs (27) get fixed into the plurality of the slots (5) and open cavity (4) of the housing (1) so as lock the rigid base (22) with housing (1). However, it is possible to provide other types of constructions for joining the rigid base (22) to the housing (1).
Referring to figure 5, it can be observed that at least a pair (25, 26) of rigid output contacts may be preferably electrically shorted over opposite face (31) of the base (22).
Referring to figures 1(a), 1(b), 3 and 7, it can be observed that the knob (10) is swingable by pivot mechanism about the pivot point (14). The knob (10) comprises an integrated carrier (11). The carrier has a recess (35) and means for latching (36) for accommodating the moving contact (16) on a lateral side (33). The moving contact (16) is mounted in recess (35) with the help of a biasing means (15). The biasing means (15) is sandwiched between inner surface (16b, not shown in the figures) of the moving contact (16) and the inner wall of the recess (35). The biasing means (15) exerts a positive outward pressure on the moving contact (16) so as to keep moving contact (16) in contact with the input and output terminals (23, 24, 25 and 26) of the fixed contact. The carrier (11) accommodates a spring (12) loaded with ball (or plunger) (13) (referred to as a spring-plunger mechanism) at a bottom surface or an underside (34, not shown in figures). The spring (12) loaded with the ball of plunger (13) is located

between the knob (10) and detent profile (8) for knob (10) position and auditing feedback to the rider as shown in figure 3.
The detent profile comprises of first (8a), second (8b) and third (8c) areas co-joined in a sequential manner. The first area is in the form of locking groove which allows the plunger / ball of the spring-plunger mechanism to be parked therein and to realize a high beam location. Similarly, the second area is in the form of locking groove which allows the plunger / ball of the spring-plunger mechanism to be parked therein and to realize a low beam position. Contrary to the first and second area, the third area (8c) is not in the form of locking groove and more particularly is formed as flat slanting (or sloping) surface. The characteristic of the detent profile of the present invention is therefore noticeably distinct from the detent profile of the prior art in terms of the feature that the detent profile of the switches of the prior art doesn't contain the third area. It may be noted that, the third area (8c) in corporation with the spring-plunger mechanism provides the restoration force which is needed to automatically restore the knob from the bottom position to the middle position (i.e. from the pass beam state to the low beam state) upon lifting of the finger from the knob. It can be said the angle of slope of the third area of the detent profile plays a vital role in terms of the overall construction of the switch as will be explained in the below paragraph.
The Applicants have observed that it is not possible to derive or obtain required restoration force (i.e. the restoration force which is needed to automatically restore the knob to the middle position) if the angle of the slope of the third area of the detent profile is less than first predetermined value. On the other hand, if the angle of the slope of the third area (8c) of the detent profile is in excess of second predetermined value, the Applicants have observed that the envelop dimensions of the switch are required to be increased (so as to provide ample amount of clearance between the adjacently located terminals). The Applicants have found that the first predetermined value of the slope of the third area of the detent profile (i.e. the minimum value) should be in excess of 20 degrees and preferably in excess of 25 degree and the second predetermined value of the slope of the third area of the detent profile (i.e. the maximum value) should be less than 45 degrees and preferably less than 40 degree. More preferably, the Applicants have observed that if the angle of slope of the third area of the detent profile is maintained at a value between 30 and 35 degree, all of the desired requirements are obtained.

Referring to figure 4, it can be observed that the triangular moving contact plate (16) comprises:
a) one input dome (17) and at least two output domes i.e. first output dome (18a) and second output dome (18b) located with respect to a pivot (29) wherein the input dome (17) is towards the pivot (29) and both output domes (18a, 18b) are away from the pivot (29); and
b) at least two guiding legs (20) for positioning the moving contact (16) into the latching means (36) provided on recess (35) on the carrier (11).
Although not necessary, the triangular moving contact plate (16) can be provided with a blank curve shape (19) relieved in between above said two output domes (18a, 18b).
In one embodiment, the triangular moving contact (16) has unequal distances between all three domes i.e. first distance (y), second distance (x) and third distance (z). The first distance (y) joining the input dome (17) and first output dome (18a) is greater than the second distance (x) joining the first output dome (18a) and the second output dome (18b). The third distance (z) joining the second dome (18b) and the input dome (17) is lesser than second distance (x) as well as than the first distance (y). Although not illustrated, the triangular moving contact can be of other shapes, such as an equilateral triangle or an isosceles triangle can have the shape as disclosed in Japanese Patent No. 4558606.
The knob (10) carrying moving contact (16) mounted on the integrated carrier (11) is sandwiched between the housing and the rigid base (22) in such a way that the knob (10) is able to move with the help of pivot mechanism (i.e. 6, 29 and 14) about the pivot point (14). However, it may be noted that alternative ways to realize the pivot mechanism are possible and attainable.
Referring to figure 6 and 3, the functioning of the dimmer cum pass switch of the present invention can be understood. The functioning of the switch consists three different functional situations of the moving contact (16) with respect to the output terminals (24, 25, 26) provided on the rigid base (22) i.e. high beam, low beam and pass beam as shown in figures 6(a), 6(b) and 6(c) respectively. The input dome (17) of the moving contact (16) remains in contact with the input terminal (23) of the rigid base (22) as depicted in figures 6(a), 6(b) and 6(c) showing all the three different functional situation. The hand actuateable knob (10) functions as a toggle switch during the operation of high beam and low beam functional

situation while functions as a push switch during the pass beam operation. During high beam functional situation, the ball (or plunger) (13) get locked into the groove (8a) of the detent profile (8) and both the output dome (18a, 18b) of the moving contact (16) are in contact with the two output terminals (25 and 26) of the fixed contact (which are shorted at the back end of the rigid base).
Similarly, during low beam functional situation, the ball (or plunger) (13) get locked into the groove (8b) of the detent profile (8). In this case, one output dome (18b in accordance with the presently depicted diagram) of the moving contact (16) is in contact with only one output terminal out of the three output terminals (24 in accordance with the presently depicted diagram) formed in the fixed contact while the other output dome of the moving contact is not in contact with the other two output terminals (25 and 26) of the fixed contact.
During pass beam functional situation, the ball (or plunger) (13) slides forward away from the groove (8b) on the sloping surface (8c) upon pressing the knob (10) and both the output domes (18a, 18b) of the moving contact (16) are in contact with the two output terminals (24 and 25) of the fixed contact (which are NOT shorted at the back end of the rigid base). Thus, it can be said that in a pass beam state, both the high beam light as well as the low beam light are working.
Upon releasing the actuating force from the knob (10) the ball (or the plunger) (13) slides back into the groove (8b) of the detent profile (8) automatically because of the restoration force that is generated by the co-operating between the sloping surface of the detent profile and the plunger-spring mechanism. It may be noted that after release of the actuating force, the knob gets locked (or parked) once again in the groove (8b) to achieve low beam functional situation.
Although, in the drawings the fixed contacts have been shown to have been formed on the rigid plate (22), it is possible to form the same on the walls of the housing, in which case, the moving contact is required to be provided on the other lateral side of the knob.
Some of the advantages of the Invention:
Thus, it can be noticed that in comparison with the dimmer and pass switch disclosed in Japanese Patent No. 4558606, the switch of the present invention does not use torsion spring for attaining the restoration force. Thus, not only the number of components gets reduced, but

also the complexity of design of the remaining components reduces. These factors thus contribute to reduction in the cost of the product, the time spent in manufacturing the product, rejection rate (for parts which are not satisfying the complex design), ease of manufacturability etc. The rockable seesaw type switch constructed in accordance with the teachings of the present invention can provide one or more of the following additional advantages: i) Single moving contact design with large distance between domes of moving contact
plate; ii) Relieved portion in between output domes facilitates to increase the center distance
between input dome and output dome of moving contact plate; iii) Moving contact plate helps to build the desired circuit; iv) Reduce number of wires in the base sub assembly in comparison with existing dipper
with pass switch; v) Reduce temperature rise of contacts in the base sub assembly; vi) Housing of the dipper with pass switch protects from water, dust and contamination
direct entry; vii) Drainage slot provided at the bottom of the housing for water and other contamination
drainage; viii) Integrated Dipper with pass functionality; and ix) Reduces number of components and over all packaging size of switch.

WE CLAIM:
1. A rockable seesaw type switch defining a forward position, a middle position and a
downward position for use in a two wheeled vehicle, said switch comprising:
a housing (1);
a rigid base plate (22), said rigid base plate being engageable with the housing (1) to
define a pivot axis;
a hand actuateable knob (10) accommodating a moving contact on a lateral side and a
plunger-spring mechanism protruding outwardly from an underside, said hand
actuateable knob being sandwiched between the rigid base plate (22) and the housing
(1) such that it exhibits pivotal movement with respect to the pivot axis;
plurality of fixed contacts that engage with the moving contact; and
an inner surface of the housing (1) is provided with a detent profile (8), the said detent
profile co-operating with the plunger-spring mechanism to generate restoration force
to automatically restore the knob from the downward position to the middle position
after release of an actuating force.
2. The rockable seesaw type switch as claimed in claim 1, wherein the switch functions as a toggle switch between the forward position and the middle position and the switch functions as a push button switch between the middle position and the downward position.
3. The rockable seesaw type switch as claimed in claim 1, wherein the housing comprises:
a pivot supporting wall (2);
opposite walls (7a, 7b) located adjacent to pivot supporting wall (2); and
bottom wall (3) joined to the said pivot supporting wall and the said opposite walls
(7a, 7b).
4. The rockable seesaw type switch as claimed in claim 3, wherein the bottom wall is formed with the detent profile.
5. The rockable seesaw type switch as claimed in claim 1, wherein the plurality of fixed contacts comprise of one input terminal and three output terminals, with a pair of adjacently located output terminals being electrically shorted.
6. The rockable seesaw type switch as claimed in claim 1, wherein the moving contact comprises a triangular metallic strip with three dome shape contacting points, a first dome contacting point acting as an input terminal, and a second and a third dome contacting points acting as output terminals.
7. The rockable seesaw type switch as claimed in claim 1, wherein the detent profile (8) comprises first, second and third areas co-joined in a sequential manner;
the first area (8a) is in the form of locking groove for allowing the plunger of the plunger-spring mechanism to be parked therein; and
the second area (8b) is in the form of locking groove for allowing the plunger of the plunger-spring mechanism to be parked therein.
8. The rockable seesaw type switch as claimed in claim 7, wherein the third area (8c) is formed as slanting (or sloping) surface.
9. The rockable seesaw type switch as claimed in claim 7, wherein an angle of the slope of the slanting surface is in the range of 20 to 45 degree, preferably in the range of 25 to 40 degree and more preferably in the range of 30 to 35 degree.
10. A rockable seesaw type switch substantially such as herein described with reference to the foregoing description and the accompanying drawings.