JP5197350B2 - Stroke amount detector - Google Patents

Description

  The present invention relates to a stroke amount detection device, and more particularly to a stroke amount detection device that detects a stroke amount of a swing arm type rear wheel suspension of a motorcycle.

  2. Description of the Related Art Conventionally, a stroke amount detection device that detects a stroke amount of a suspension for a rear wheel of a motorcycle is known.

In Patent Document 1, a rod-shaped stroke amount sensor capable of detecting an axial sliding amount is directly attached to a shock absorber constituting a swing arm type rear wheel suspension, and based on an output value of the stroke amount sensor. An apparatus for detecting the stroke amount of the rear wheel suspension is disclosed.
JP 7-208529 A

  However, in the stroke amount detection device described in Patent Document 1, the stroke amount sensor that detects the sliding amount in the axial direction is relatively expensive, and in order to secure a mounting space for the stroke amount sensor, There existed a subject that shape change of the swing arm etc. which are arrange | positioned around needed.

  SUMMARY OF THE INVENTION An object of the present invention is to solve the above-described problems of the prior art and provide a stroke amount detection device that can detect the stroke amount of a swing arm type rear wheel suspension of a two-wheeled vehicle using a rotation angle sensor.

  In order to achieve the above object, the present invention is directed to a stroke amount detection device for a rear wheel suspension for a two-wheeled vehicle including a swing arm pivotally supported on a vehicle body frame by a pivot shaft, and is directed substantially parallel to the pivot shaft. A rotation angle sensor attached to the vehicle body frame, one end of which is coupled to the rotation shaft of the rotation angle sensor, and the other end of the swing at a position rearward of the vehicle body relative to the pivot shaft. The first feature is that a joint that is rotatably attached to the arm and is extendable in the axial direction is provided.

  A second feature is that the rotation shaft of the rotation angle sensor and the other end of the joint are both disposed above the vehicle body with respect to the pivot shaft.

  The swing arm extends upward from the rear side of the pivot shaft to the vehicle body, and has an extension portion to which an upper mounting portion of a shock absorber is fixed at an upper end portion thereof, and the other end portion of the joint is The third feature is that it is attached to the extending portion.

  In addition, a rotation shaft of the rotation angle sensor is disposed on the vehicle body front side with respect to the pivot shaft, and the joint is substantially parallel to the swing arm at a swing limit position on the upper side of the swing arm. There is a fourth feature in that it is arranged in the above.

  Furthermore, there is a fifth feature in that the joint is configured by slidably combining at least two different diameter pipes.

  According to the first feature, the rotation angle sensor has a rotation shaft oriented substantially parallel to the pivot shaft, and is attached to the rotation angle sensor attached to the vehicle body frame, one end is connected to the rotation shaft of the rotation angle sensor, and the other end is pivoted. Since it is attached to the swing arm at a position on the rear side of the vehicle body from the shaft so as to be rotatable, and has a joint that can be expanded and contracted in the axial direction, the rotation shaft of the rotation angle sensor rotates as the swing arm swings. Thus, the swing amount of the swing arm can be detected by the rotation angle sensor. Accordingly, it is possible to detect the stroke amount of the rear wheel suspension of the two-wheeled vehicle using a rotation angle sensor that is simpler in structure than the telescopic stroke amount sensor. In addition, the stroke amount of the rear wheel suspension can be detected without significantly changing the shock absorber and its peripheral parts as compared with the configuration in which the stroke amount sensor is directly attached to the shock absorber. Thereby, it becomes easy to attach the stroke amount detection device to the rear wheel suspension of the existing motorcycle by retrofitting.

  According to the second feature, since the rotation shaft of the rotation angle sensor and the other end of the joint are both disposed above the pivot shaft relative to the vehicle body, the rotation angle sensor and the joint are disposed at positions away from the road surface. As a result, the rotation angle sensor and the movable parts of the joint can be protected from mud and moisture. Further, the stroke amount detection device can be attached without reducing the minimum ground clearance of the motorcycle.

  According to the third feature, the swing arm is provided with an extending portion that extends upward from the vehicle body rear side of the pivot shaft and has an upper end portion to which the upper mounting portion of the shock absorber is fixed. Since the end portion is attached to the extension portion, the joint can be attached to the swing arm using the extension portion for attaching the shock absorber. This makes it possible to attach the stroke amount detection device without greatly changing the structure and arrangement of the swing arm, shock absorber, and the like.

  According to the fourth feature, the rotation shaft of the rotation angle sensor is disposed on the vehicle body front side of the pivot shaft, and the joint is substantially parallel to the swing arm at the upper swing limit position of the swing arm. Because it is installed, the rotation angle of the rotary shaft relative to the swing angle of the swing arm is increased to improve the detection accuracy of the stroke amount, and the stroke amount detection device is operated within a range in which the joint can easily slide. Is possible.

  According to the fifth feature, since the joint is an expansion joint in which at least two different diameter pipes are slidably combined, it is possible to obtain a joint that can expand and contract in the axial direction with a simple structure.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a side view of a motorcycle 1 to which a stroke amount detection device according to an embodiment of the present invention is applied. A pair of left and right front forks 3 that pivotally support the front wheel WF is attached to the front end of the body frame 2 of the motorcycle 1 so as to be swingable by a steering handle 4. An engine 5 is suspended below the body frame 2, and the front side of the body frame is covered with a front cowl 6 as an exterior part. A fuel tank 7 is disposed at the upper part of the vehicle body frame 2, and a seat 8 and a seat cowl 9 on which a driver is seated are attached to the rear side thereof.

  A swing arm 12 that rotatably supports a rear wheel WR by an axle 15 is attached to a lower portion of the rear end of the body frame 2 so as to be swingable by a pivot shaft 10. The rotational driving force of the engine 5 is transmitted to the rear wheel WR via the drive chain 14. The force that causes the swing arm 12 to swing counterclockwise in the figure when the motorcycle 1 is traveling is absorbed by the shock absorber 11 with a spring. A link mechanism 13 that connects the vehicle body frame 2 and the swing arm 12 via the shock absorber 11 is provided below the shock absorber 11. In the present embodiment, the entire suspension device in which the link mechanism 13, the swing arm 12, and the shock absorber 11 are combined is referred to as a rear wheel suspension 60.

  FIG. 2 is a perspective view showing a state in which the swing arm 12 is separated from the vehicle body frame 2. The same reference numerals as those described above denote the same or equivalent parts. The swing arm 12 has a pair of left and right pivot holes 20 provided in the vehicle body frame 2 and a pivot hole 30 provided at the front end portion of the swing arm 12 through a pivot shaft 22 constituting the pivot shaft 10. It is pivotally supported with respect to the body frame 2 so as to be swingable. A lock nut 23 is fastened to the end of the pivot shaft 22. A pair of left and right cushion connecting rod mounting portions 21 are formed at the lower rear portion of the pivot hole 20. A front end portion of a cushion connecting rod 45 to be described later is rotatably supported on the cushion connecting rod mounting portion 21.

  A pair of left and right extending portions 31 extending from the position behind the pivot hole 30 to the upper side of the vehicle body is provided on the upper portion of the swing arm 12. An upper mounting portion 41 of the shock absorber 11 is pivotally supported by a pivot bolt 32 and a nut 33 on the upper end portion of the extending portion 31. Note that a through hole (not shown) through which the shock absorber 11 is inserted from below is formed between the left and right extending portions 31.

  The link mechanism 13 includes a cushion arm 40 having a substantially triangular shape when viewed from the side, and a cushion connecting rod 45 having a pair of left and right arm members. The cushion arm 40 and the lower attachment portion 42 of the shock absorber 11 are rotatably supported by a pivot bolt 43 and a nut 44 that penetrate the pivot hole 40a. The cushion arm 40 and the cushion arm mounting portion 36 provided at the lower part of the swing arm 12 are pivotally supported by a pivot bolt 34 and a nut 35 that pass through the pivot hole 40b.

  The cushion connecting rod 45 and the cushion connecting rod mounting portion 21 provided on the vehicle body frame 2 are rotatably supported by a pivot bolt 24 and a nut 25 that pass through a pivot hole 45a on the front side of the vehicle body. The cushion connecting rod 45 and the cushion arm 40 are rotatably supported by a pivot bolt 46 and a nut 47 that penetrate the pivot hole 45b on the rear side of the cushion connecting rod 45 and the pivot hole 40c of the cushion arm 40.

  The suspension 60 for the rear wheel of the motorcycle 1 having the link structure as described above can realize a variable ratio such that the stroke amount ratio of the shock absorber 11 decreases as the swing angle of the swing arm 12 increases, for example. And The characteristics of the variable ratio can be arbitrarily set by setting the dimensions of the link mechanism 13.

  FIG. 3 is an enlarged perspective view of the swing arm 12. A pivot hole 30 through which the pivot shaft 22 (see FIG. 2) passes is provided at the front end of the swing arm 12, and a long hole 37 through which the axle 15 of the rear wheel WR passes is provided at one rear end. It has been. As described above, a pair of left and right extending portions 31 to which the upper mounting portion 41 of the shock absorber 11 is attached are formed at the rear of the pivot hole 30 and near the center of the vehicle body. An expansion joint attachment portion 52 is provided in the approximate center of the extension portion 31.

  The stroke amount detection device according to the present invention includes a rotation angle sensor 50 composed of a potentiometer, and an expansion joint 51 that can expand and contract in the axial direction. The rotation angle sensor 50 is attached to the vehicle body frame 2 (see FIGS. 2 and 6). The expansion joint 51 has a configuration in which an outer cylinder 51a and an inner cylinder 51b having different diameters are slidably combined. In the present embodiment, one end portion of the outer cylinder 51a is fixed to the rotation shaft of the rotation angle sensor 50 so as not to rotate, and one end portion of the inner cylinder 51b is rotatably supported by the expansion joint attachment portion 52. ing.

  4 and 5 are explanatory diagrams showing the relationship between the swinging motion of the swing arm 12 and the operating state of the stroke amount detection device. 6 and 7 are partially enlarged views corresponding to FIGS. 4 and 5, respectively. The same reference numerals as those described above denote the same or equivalent parts. 4 and 6 each show a state in which the swing arm 12 is in the initial position (for example, a state in which the shock absorber 11 is fully extended). On the other hand, FIGS. 5 and 7 show a state where the swing arm 12 has stroked from the state of FIGS. 4 and 6 to the upper swing limit position (for example, a state where the shock absorber 11 has made a full stroke). 5 shows a state where the position of the vehicle body frame 2 with respect to the road surface 100 is the same as that in FIG. 4 and only the swing arm 12 is swung counterclockwise. In FIG. 5, the description of the link mechanism 13 is omitted.

  The rotation angle sensor 50 is attached by attachment stays 53 and 56 to the back side of the left side member in the vehicle width direction of the body frame 2. The rotation shaft 53 of the rotation angle sensor 50 is disposed so as to be substantially parallel to the pivot shaft 10 of the swing arm 12, that is, the pivot shaft 22, and the outer cylinder of the expansion joint 51 is disposed at the end of the rotation shaft 53. One end of 51a is fixed.

  An end portion of the inner cylinder 51b of the expansion joint 51 disposed substantially parallel to the longitudinal direction of the vehicle body is rotatably attached to the expansion joint mounting portion 52 by a pillow ball 55 and a mounting bolt 54. The expansion joint 51 is in an extended state at the initial position shown in FIGS. When the swing arm 12 swings counterclockwise, the rotation shaft 53 is rotated counterclockwise while the distance between the axes is reduced along with the swing. Thereby, even when the rotation angle sensor 50 is arranged at a position separated from the pivot shaft 10 of the swing arm 12, the rotation shaft 53 can be smoothly rotated along with the swinging operation of the swing arm 12.

  In the present embodiment, in an initial state before the swing arm 12 swings, the axis connecting the pivot shaft 10 and the axle 15 in a side view and the axis of the expansion joint 51 are separated from each other toward the rear of the vehicle body. Is set to The two axes are set to be substantially parallel in the full stroke state. According to such setting, the ratio of the rotation angle of the rotary shaft 53 to the swing angle of the swing arm 12 increases as the full stroke state is approached, and the detection accuracy of the swing arm swing angle near the full stroke is improved. Is possible. In addition, the relationship between the position where both axes are substantially parallel and the swing angle of the swing arm 12 can be arbitrarily set.

  Since the correspondence relationship between the swing angle of the swing arm 12 and the rotation angle of the rotary shaft 53 can be derived in advance at the time of design, the swing angle of the swing arm 12 is detected based on the output value of the rotation angle sensor 50. It becomes possible. If the swing angle of the swing arm 12 is determined, the corresponding amount of contraction of the shock absorber 11 and the amount of vertical movement of the rear wheel WR can be arbitrarily calculated based on the design dimensions. .

  As described above, according to the stroke detection device of the present invention, the stroke detection device can be attached without significantly changing the shape of the shock absorber 11, the swing arm 12, or the like. It is possible to attach the stroke amount detection device relatively easily even to an existing model that is not assumed. In addition, since the stroke amount detection device can be easily attached and detached, it is possible to easily set the specification difference in the same vehicle type without using different dedicated components.

  It should be noted that the detection of the stroke amount of the rear wheel suspension may be executed in either a stopped state or a traveling state. The detected stroke amount information is automatically adjusted according to the amount of stroke when the vehicle is stopped, that is, the load capacity. It can be used to operate the headlight or keep the optical axis of the headlight constant during traveling.

  In the expansion joint 51, the inner cylinder 51b may be fixed to the rotation shaft, and the outer cylinder 51a may be attached to the expansion joint attachment portion 52. In addition to the structure in which a plurality of cylindrical members having different diameters are slidably combined as in the above-described embodiment, the expansion joint 51 can be variously modified such as a structure that enables reciprocating motion by a wheel and rail structure. It is.

  As described above, according to the stroke amount detection device of the present invention, the rotation angle sensor is attached to the vehicle body frame so that the rotation shaft is oriented substantially parallel to the pivot shaft, and one end of the expansion joint is connected to the rotation shaft. Since the other end of the expansion joint is rotatably attached to the swing arm at a position on the rear side of the vehicle body from the pivot shaft, the rotation angle sensor rotates as the swing arm swings. The shaft rotates, and the swing amount of the swing arm can be detected by the rotation angle sensor. As a result, the stroke amount of the rear wheel suspension of the two-wheeled vehicle can be detected by using a rotation angle sensor that has a simpler structure than the telescopic stroke sensor.

  In addition, the shape and structure of the expansion joint and the rotation angle sensor, the mutual arrangement relationship between the rotation angle sensor, the expansion joint and the swing arm, the shape of the swing arm, and the like are not limited to the above-described embodiment, and various changes can be made. . For example, the rotation angle sensor may be composed of a rotary encoder or the like. The stroke amount detection device according to the present invention is not limited to a motorcycle, and can be applied to swing arm type suspensions of various vehicles.

1 is a side view of a motorcycle to which a stroke amount detection device according to an embodiment of the present invention is applied. It is a perspective view which shows the state which isolate | separated the swing arm from the vehicle body frame. It is an expansion perspective view of a swing arm. It is explanatory drawing (initial state) which shows the relationship between the rocking | fluctuation operation | movement of a swing arm, and the operation state of a stroke amount detection apparatus. It is explanatory drawing (full stroke state) which shows the relationship between the rocking | fluctuation operation | movement of a swing arm, and the operation state of a stroke amount detection apparatus. FIG. 5 is a partially enlarged view of FIG. 4. FIG. 6 is a partially enlarged view of FIG. 5.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Motorcycle, 2 ... Body frame, 5 ... Engine, 10 ... Pivot shaft, 11 ... Shock absorber, 12 ... Swing arm, 13 ... Link mechanism, 15 ... Axle, 22 ... Pivot shaft, 30 ... Pivot hole, 31 ... Extension part, 50 ... Rotation angle sensor, 51 ... Expansion joint (joint), 51a ... Outer cylinder, 51b ... Inner cylinder, 52 ... Expansion joint mounting part, 60 ... Rear wheel suspension, WR ... Rear wheel

Claims (3)

In a stroke amount detection device for a rear wheel suspension for a motorcycle including a swing arm (12) pivotally supported on a vehicle body frame (2 ) by a pivot shaft (10) ,
A rotation angle sensor (50) having a rotation shaft (53) oriented substantially parallel to the pivot shaft (10) and attached to the vehicle body frame (2) ;
One end is coupled to the rotation shaft (53) of the rotation angle sensor (50) , and the other end is rotatably attached to the swing arm (12) at a position rearward of the vehicle body from the pivot shaft (10). A joint (51) that is extendable in the axial direction ,
The rotation shaft (53) of the rotation angle sensor (50) and the other end of the joint (51) are both disposed above the vehicle body from the pivot shaft (10),
A rotation shaft (53) of the rotation angle sensor (50) is disposed on the front side of the vehicle body from the pivot shaft (10),
The joint (51) is disposed so as to be substantially parallel to the swing arm (12) at the upper swing limit position of the swing arm (12).
In an initial state before the swing arm (12) swings, the axis connecting the pivot shaft (10) and the axle (15) of the swing arm (12) and the axis of the joint (51) The stroke amount detection device is set so as to be spaced apart from each other . An extension portion (31) that extends upward from the rear side of the pivot shaft (10) to the swing arm (12) and has an upper mounting portion (41) of the shock absorber (11) fixed to the upper end portion thereof. Is provided,
Stroke amount detecting apparatus according to claim 1, wherein the other end of the joint (51), characterized in that attached to the extending portion (31). The stroke amount detection device according to claim 1 or 2 , wherein the joint (51) is configured by slidably combining at least two different diameter pipes.

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