PROP STAND SWITCH MECHANISM FOR A MOTORCYCLE

FIELD OF THE INVENTION

[0001] The present subject matter is related, in general to a prop stand, and in particular, but not exclusively to a prop stand switch mechanism for a motorcycle.

BACKGROUND OF THE INVENTION

[0002] Conventionally, a prop stand for a two wheeled vehicle is an auxiliary stand provided in the vehicle to put the vehicle on stand effortlessly when not in use. When the vehicle is parked using prop stand, both the wheels touch the ground. Often an operator riding such vehicle forgets to retract the prop stand, used during parking, and starts riding it with the prop stand in an operative position. This forgetfulness may jeopardize the safety of the operator as well as other occupants, if any, and cause accidental hazards. The contact between the ground and the prop stand, while the vehicle is moving or taking a turn, may cause jerks and the operator may easily lose control of the vehicle leading to a fatal accident.

[0003] To overcome the same, several prop stand switch mechanisms have been proposed till date to alert the vehicle operator about the prop stand position through an audible signal or a display means. Such mechanisms are responsive to a change in position of the prop stand and are actuated with direct contact to the prop stand which is essential to ensure reliable sensing. However, there are several problems associated with them. A typical prop stand switch in a two wheeled vehicle, like a scooter type motorcycle, is mounted on the same bracket as the prop stand due to which it is close to the ground. Since the prop stand switch has same ground clearance as that of the prop stand, it is prone to obstructions from the ground. If the vehicle itself has a lower ground clearance, then such prop stand switch is also prone to continuous mud and water splash during rainy season. Moreover, when the vehicle encounters rain or passes through a flooded area, the switch is further prone to water entry and may fail to give any response to the vehicle operator. Hence the positioning of the prop stand switch becomes very crucial in such type of vehicles. Further any attempt for water proofing the switch leads to increase in the complexity of the switch, weight as well as cost.

[0004] Furthermore, the prop stand switch is connected to the prop stand through a joining member. The rotation of prop stand about a pivot shaft, extending laterally with respect to the vehicle body frame, forms a polynomial curve. This causes slackness and tension in the joining member. The combination of slackness and tension is not suitable for transfer of the input to the prop stand switch. The joining member should be flexible to facilitate correct input. Therefore, it is preferable to eliminate or reduce slackness in the prop stand switch mechanism.

[0005] The present invention is directed to overcoming all or any of the problems as set forth above and obviate the lacunae in the prior art. Hence it is one of the objects of the present subject matter to provide a prop stand switch mechanism for a two wheeled vehicle with increased durability wherein the prop stand switch is protected from the obstructions on the road like mud, water or the like. It is another object of the present invention to ensure reliability of the prop stand switch mechanism by reducing the slackness in the joining member even when the prop stand switch and the prop stand are not mounted jointly.

SUMMARY OF THE INVENTION

[0006] The present subject matter relates to a prop stand switch mechanism for a two-wheeled vehicle comprising: a prop stand installed at a lower portion of the said vehicle, positioned generally parallel to the ground in a housing position and at an angle to the vertical in a use position, such that the said prop stand is biased to rotate to either the housing position or the use position; a prop stand switch containing a switch pin disposed angularly to the ground, the prop stand switch being in open circuit when the prop stand is in housing position, the prop stand switch being in closed circuit when the prop stand is in use position; a pre-tensioned switch spring; a wire clamp, fixed to an upper portion of the prop stand and the said switch spring connected to it in such a way that one end of the said switch spring is connected to the said switch pin and the other end of the said switch spring is connected to the wire clamp, and switch mounting bracket, connected at one end to a frame of the vehicle by welding and holding the said prop stand switch at the other end.

[0007] According to an aspect of the present subject matter, the prop stand switch has more ground clearance than the said prop stand.

[0008] The foregoing objectives and summary provide only a brief introduction to the present subject matter. To fully appreciate these and other objects of the present subject matter as well as the subject matter itself, all of which will become apparent to those skilled in the art, the ensuing detailed description of the invention and the claims should be read in conjunction with the accompanying drawings. The summary is not intended to identify essential features of the claimed subject matter nor is it intended for use in determining or limiting the scope of the claimed subject matter.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The above and other features, aspects, and advantages of the present subject matter will be better understood with regard to the following description, appended claims and accompanying drawings where:

Figure 1 shows a side view of a typical two wheeled vehicle.

Figure 2 shows an exploded view of a prop stand switch mechanism when the prop stand is in housing position.

Figure 3 shows an exploded view of the prop stand switch mechanism when the prop stand is in use position.

[00010] In the figures, the same reference numerals are given to members and parts performing the same functions.

DETAILED DESCRIPTION OF THE INVENTION

[00011] The subject matter described herein relates to a prop stand switch mechanism for a two wheeled vehicle. Various other features and embodiments of the mechanism according to the present invention here will be discernible from the following further description thereof, set out hereunder. In the ensuing exemplary embodiments, the vehicle is a scooter type motorcycle. However it is contemplated that the concepts of the present invention may be applied to other types of vehicles within the spirit and scope of this invention including a moped, motorcycle or a scooter type motorcycle with a step thru space. It is to be noted that the detailed explanation of the constitution of parts other than the subject matter which constitutes an essential part has been omitted at suitable places.

[00012] In the present subject matter, the proposed prop stand switch mechanism is mounted at a lower portion of the scooter type motorcycle to detect the angular position of a prop stand with respect to the ground.

[00013] Figure 1 describes a side view of a typical scooter type motorcycle. Typically such a motorcycle includes a body frame assembly made up of several tubes welded together which usually supports the body of the said motorcycle. The vehicle has a steerable anterior wheel 110 and a driven rear wheel 111 driven by driving force generated by the power unit. The anterior wheel 110 is partially covered by an anterior wheel cover 113 whereas the rear wheel 111 is partially covered by a rear wheel cover 109. The frame assembly 101 of the straddle type vehicle is an elongated structure, which typically extends from a forward end to a rearward end of the vehicle. It is generally convex in shape, as viewed from a side elevational view. The frame assembly 101 includes a head tube and a down tube that extends downward from the head tube, and is covered by a plurality of vehicle body covers including a front panel 115, a leg shield 116, an under seat cover 117 and a side panel 112.

[00014] A handlebar assembly 105 and a seat assembly 106 are supported at opposing ends of the frame assembly and a generally open area is defined there between known as floorboard 107 which functions as a step through space. A fuel tank (not shown) that stores fuel supplied to the engine is disposed at the rear end of the vehicle above the rear wheel 111. It is present on the upper side of the power unit along with a fuel tank cap. The seat for a driver and a pillion is placed forward to the fuel tank and rearwardly of the floorboard 107. A muffler is provided to the right side of the rear wheel, and connects to the engine.

[00015] Typically, a front suspension assembly 103 is operatively positioned between the anterior wheel 110 and the frame assembly.

Similarly a rear suspension assembly 114 is operatively positioned between the rear wheel 111 and the frame assembly. The front suspension assembly 103 commonly is a telescopic fork arrangement while the rear suspension assembly 114 is a hydraulic damped arrangement.

[00016] In the said vehicle, the rear suspension swing arm typically supports the power unit which is configured to drive the rear wheel 111 of the vehicle. The power unit is structured such that an engine 102 and a swing case 108, which are well known for this form of straddle type vehicle, are integrally constructed. In an embodiment of the present invention, the engine is a four stroke single cylinder internal combustion engine and the swing case 108 is connected to a left side surface of a crankcase of the engine 102 so as to extend forward.

[00017] It is disposed on the vehicle frame with one end of the swing case 108 attached to the rear wheel hub in such a way that the power unit is substantially angularly disposed to the ground. The engine 102 is arranged horizontally, that is, its crankshaft is placed perpendicularly to the longitudinal direction of the vehicle body. Since the basic construction of an engine is known to those versed in the art, the details have been omitted. The said power unit is surrounded by a shroud (not shown) with a fan to enhance forced cooling of the power unit. The shroud present over the power unit is also known as cooling cowl and may be made of plastic resin or the likes.

[00018] Figure 2 shows an exploded view of the prop stand switch mechanism mounted on a lower portion of the scooter type motorcycle connected to a prop stand 118. It comprises of a prop stand switch 200 containing a switch pin 201, a switch mounting bracket 204, a wire clamp 203 and a switch spring 202. The said switch 200 is mechanically connected to the prop stand 118 and electrically connected with an audio means or a display on the instrument cluster of the said motorcycle or both.

[00019] The prop stand 118, fixed lateral to the vehicle body frame, supports the vehicle such that vehicle inclines to the left side without falling. The prop stand 118 generally includes a prop stand mounting bracket 120 mounted on the lower portion of the left side body frame 101 of the scooter type motorcycle, a pivot bolt 121, a stand spring 119 and a pivot shaft (not shown) extending laterally with respect to the body frame 101. The prop stand 118 is mounted on the prop stand mounting bracket 120 and configured to pivot about the pivot bolt 121 along the axis of the pivot shaft. The prop stand 118 and the pivot bolt 121 are turned together relative to the prop stand mounting bracket 120. The prop stand 118 is usually spring loaded with the help of the stand spring 119 and generally functions in two positions; "housing" position and "use" position. In the housing position as shown in Figure 2, the prop stand 118 is approximately parallel to the ground and is non-operative whereas in the use position, it is at an angle to the vertical and is operative i.e. supports the vehicle in its standing position during parking. The prop stand 118 is biased to rotate to either the housing position or the use position and is retained in either of the positions through the stand spring 119.

[00020] Further the prop stand switch 200 is also disposed angularly to the ground. The switch spring 202 connects the switch pin 201 to the wire clamp 203 and is preferably pre-tensioned to avoid rattling and reduce slackness. The pre-tensioned switch spring 202 reduces the direct force acting on the switch when the prop stand 118 is pivoted to a use position. Preferably, the switch spring is a coil spring. The prop stand switch 200 is in open circuit when the prop stand 118 is in housing position whereas the prop stand switch 200 is in closed circuit when the prop stand 118 is in use position. According to an embodiment of the present subject matter, the switch circuit gets closed when the switch pin 201 is pulled beyond 2.5 mm.

[00021] The wire clamp 203 is fixed to an upper portion of the prop stand 118 and the switch spring 202 is connected to the wire clamp 203 in such a way that one end of the switch spring 202 is connected to the switch pin 201 and the other end of the switch spring 202 is connected to the wire clamp 203. The wire clamp 203 reduces the angular movement of the prop stand 118 during operation. According to a preferred embodiment of the present subject matter, the wire clamp 203 is approximately curved in shape and connects to the prop stand 118 at two co-axial locations. The wire clamp 203 is designed to keep the switch spring 202 in contact with the wire clamp 203 during the entire rotation of the prop stand 118 from housing to use position thereby avoiding rattling. The wire clamp curve is modifiable to suit the appropriate extension of the switch spring within the working limit of the prop stand switch.

[00022] Further, the switch spring 202 is connected to the switch pin 201 at one end through a point joint giving three rotational degrees of freedom whereas to the prop stand 118 via wire clamp with three rotational and one translational degrees of freedom. The translational degree of freedom helps reduce the slackness while working within the tension region. Furthermore, the switch mounting bracket 204 is provided, connected to the vehicle frame 101 at one end and holding the said prop stand switch 200 at the other end. According to a preferred embodiment of the present subject matter, the switch mounting bracket 204 is connected to the vehicle frame 101 by welding. The switch mounting bracket is generally connected to the frame at a height to the prop stand hence increasing the ground clearance of the prop stand switch and reducing its probability of failure due to water or mud.

[00023] The working of the prop stand switch mechanism is now described. Initially the switch pin 201, the switch spring 202 and the wire clamp 203 are connected in series along one axis. The prop stand switch 200 remains in open circuit when the prop stand 118 is in housing position. Figure 3 shows an exploded view of the prop stand switch mechanism when the prop stand is in use position. When the prop stand 118 operates from housing position to use position and switch pin 201 gets pulled beyond 2.5 mm, the switch circuit gets closed and it generates an output signal. The output of the said prop stand switch 200 is carried to an operator of the said vehicle through an audio or display method. According to an embodiment of the present subject matter, the switch circuit gets closed when the prop stand rotates about 75 degrees from the housing position as against a maximum of 105 degrees.

[00024] The present subject matter and its equivalent thereof offer many advantages, including those which have been described henceforth. The prop stand switch 200 owing to its construction as described has better ground clearance than the prop stand itself since the prop stand switch is mounted at a height compared to the prop stand. Due to its better ground clearance, the styling parts of the scooter type motorcycle cover the prop stand switch and hence it is saved from dust and water while the vehicle is moving on road. Moreover, the obstructions on the road like stones etc. do not hinder the operation of the prop stand switch. Thus the present subject matter has the advantages of simple structure, reliable working and enhanced life.

[00025] According to an aspect of the present subject matter, the prop stand switch mechanism as aforementioned is best suited for a scooter type motorcycle having a low floorboard or a scooter type motorcycle with a step thru space.

[00026] The present subject matter is thus described. The description is not intended to be exhaustive nor is it intended to limit the invention to the precise form disclosed. It will be apparent to those skilled in the art that the disclosed embodiments may be modified in light of the above description. The embodiments described are chosen to provide an illustration of principles of the invention and its practical application to enable thereby one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. Therefore the forgoing description is to be considered exemplary, rather than limiting, and the true scope of the invention is that described in the appended claims.

We claim:

1. A prop stand switch mechanism for a two-wheeled vehicle comprising:

a prop stand installed at a lower portion of the said vehicle, positioned generally parallel to the ground in a housing position and at an angle to the vertical in a use position, such that the said prop stand is biased to rotate to either the housing position or the use position,

a prop stand switch containing a switch pin disposed angularly to the ground, the prop stand switch being in open circuit when the prop stand is in housing position, the prop stand switch being in closed circuit when the prop stand is in use position, a pre-tensioned switch spring,
a wire clamp, fixed to an upper portion of the prop stand and the said switch spring connected to it in such a way that one end of the said switch spring is connected to the said switch pin and the other end of the said switch spring is connected to the wire clamp, and a switch mounting bracket, connected at one end to a frame of the vehicle by welding and holding the said prop stand switch at the other end.

2. The prop stand switch mechanism as claimed in claim 1, wherein
the said prop stand switch has more ground clearance than the said
prop stand.

3. The prop stand switch mechanism as claimed in claim 1, wherein the said prop stand switch is covered with a styling part of the vehicle.

4. The prop stand switch mechanism as claimed in claim 1, wherein the said switch spring includes a coil spring.

5. The prop stand switch mechanism as claimed in claim 1, wherein the output of the said prop stand switch is carried to an operator of the said vehicle through an audio or display method.

6. The prop stand switch mechanism as claimed in any of the preceding claims wherein the said two wheeled vehicle includes a scooter type motorcycle.

7. A prop stand switch mechanism for a two-wheeled vehicle substantially as herein described and illustrated by the accompanying drawings.