JPH07215260A - Vehicle speed detector for small vehicles - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a vehicle speed detection device for a small vehicle capable of preventing foreign matter from entering and adhering from the outside and maintaining high accuracy. [Constitution] A drive member 50 is provided on a final output shaft 49 of an engine 22, and the drive member 50 is a cover member 5.
In a small-sized vehicle which is covered with 1 and which transmits the engine output from the drive member 50 to the rear wheels, a bottomed cylindrical rotating member 56 is provided at the end 49a of the output shaft 49, and the rotating member is provided inside the cover member 51. The rotation speed detecting means 54 of 56 are arranged, and the rotation speed detecting means 54 is housed in a space S1 formed by the cover member 51 and the rotating member 56.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle speed detecting device for a small vehicle, and more particularly to an electric vehicle speed detecting device for a small vehicle.

[0002]

2. Description of the Related Art As a means for detecting the vehicle speed of a small vehicle such as a motorcycle, generally, a gear train for extracting the rotational movement of the front wheels is housed in a gear box provided near the lower end of a front fork. There is a mechanical vehicle speed detecting device that transmits the output rotational movement of the above to a speedometer via a meter cable.

By the way, in a motorcycle, since it is required to reduce the inertia of the front portion of the motorcycle in order to improve the running performance, the mechanical vehicle speed detecting device described above is used to output the final output of the engine from the lower end of the front fork. There is also one that moves to the vicinity of the shaft and transmits the rotational motion of the engine output shaft to the speedometer via a cable (JP-A-64).
-29771).

However, in the mechanical type vehicle speed detecting device, an error easily occurs due to wear of the gear train, sliding resistance of the cable, etc.
Regular maintenance and replacement of parts were required.
Also, there is a limit to the degree of freedom in arranging the cables.

Therefore, in recent years, an electric vehicle speed detecting device has been proposed in which the rotational movement of the engine output shaft is electrically detected and transmitted to a speedometer.

A specific example of the electric vehicle speed detecting device is shown in FIGS. 8 and 9 which is a sectional view taken along line XX of FIG. As shown in FIGS. 8 and 9, a plurality of gear trains 3 are arranged in the transmission case 2 at the rear of the engine 1 to reduce the rotational power from the engine 1. A drive sprocket 5 is provided at the end 4a of the drive shaft 4, which is the final output shaft from the engine 1. The drive sprocket 5 is covered with a sprocket cover 6.

On the other hand, a driven sprocket 8 is mounted on the rear wheel coaxially with the rear axle 7 integrally with the rear wheel, and the driven sprocket 8 and the drive sprocket 5 are attached.
A chain 9 is wound around and. That is, the rotation speed of the drive shaft 4 is proportional to the rotation speed (vehicle speed) of the rear wheels.

A sensor rotor 10 made of a magnetic material is integrally attached to the drive shaft 4 at the end 4b of the drive shaft 4. As shown in FIG. 8, the sensor rotor 10 has a disk shape in which uneven portions 11 are alternately arranged on the outer peripheral portion, and the speed sensor 12 is provided on the inner surface 6a of the sprocket cover at a position facing these uneven portions 11, for example.
Are arranged. The sensor rotor 10 and the speed sensor 12 constitute a vehicle speed detection device 13.

The speed sensor 12 is provided with, for example, a magnetic circuit, magnetically detects passage of the uneven portion 11 due to rotation of the sensor rotor 10, and converts a change in magnetic amount into an electric signal (pulse wave). The pulse wave passes through the wire harness 14 and the arithmetic unit 15 on the way to the speedometer 1
6 to display the rotation speed of the sensor rotor 10, that is, the vehicle speed.

[0010]

However, in the sprocket cover, foreign matters such as sand, stones, oil, water and mud often enter the sprocket cover due to the drive sprocket and the chain rotating at high speed, and high precision is required. The inside of the sprocket cover is not a preferable environment for the sensor rotor and the speed sensor.

Further, if foreign matter such as moisture or sand iron that may affect the electric / magnetic circuit adheres to the sensor rotor or the speed sensor, the accuracy of the detection device will deteriorate.

Therefore, there is a vehicle speed detecting device provided outside the sprocket cover (see Japanese Patent Laid-Open No. 5-85449), but a member for connecting the drive shaft end and the detecting device is required. However, there is a case that the shape of the sprocket cover needs to be changed drastically. If the vehicle speed detection device is provided outside the sprocket cover, the sprocket cover may be spoiled.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a vehicle speed detecting device for a small vehicle which can prevent foreign matter from entering and adhering from the outside and maintain high accuracy.

Another object of the present invention is to provide a vehicle speed detecting device for a small vehicle which can easily remove the foreign matter even if the foreign matter adheres to the vehicle speed detecting device.

[0015]

In order to solve the above-mentioned problems, a vehicle speed detecting device for a small vehicle according to the present invention is provided with a drive member on the final output shaft of an engine as described in claim 1. In a small vehicle in which the drive member is covered with a cover member and transmits the engine output from the drive member to the rear wheels, a bottomed cylindrical rotary member is provided at the end of the output shaft, and the rotary member is provided inside the cover member. While the rotational speed detecting means is arranged, the rotational speed detecting means is housed in a space formed by the cover member and the rotating member.

In order to solve the above-mentioned problems, as described in claim 2, a cylindrical member is provided inside the cover member on the outer peripheral side of the rotating member, and the cylindrical member and the rotating member are provided. A seal device is interposed between the and.

Further, in order to solve the above-mentioned problems,
As described in claim 3, the rotation speed detecting means is detachably attached from the outside of the cover member.

[0018]

According to the present invention having the above-mentioned structure, the final output shaft of the engine is provided with the drive member, and the drive member is covered with the cover member and transmits the engine output from the drive member to the rear wheels. A rotating member having a bottomed cylindrical shape is provided at the output shaft end, and rotation speed detecting means for the rotation member is arranged inside the cover member, and the rotation speed detecting means is formed from the cover member and the rotation member. Since it is housed in the space, it is possible to prevent foreign matter from entering and adhering to the rotation speed detecting means from the outside, and as a result, the accuracy of the vehicle speed detecting device can be maintained high.

Further, a cylindrical member is provided inside the cover member on the outer peripheral side of the rotating member, and a sealing device is interposed between the cylindrical member and the rotating member.
It is possible to prevent foreign matter, particularly water and fine dust, from entering and adhering to the rotation speed detecting means from the outside, and as a result, it is possible to maintain the accuracy of the vehicle speed detecting device even higher.

Further, since the rotation speed detecting means is detachably attached from the outside of the cover member, even if foreign matter adheres to the vehicle speed detecting device, the foreign matter can be easily removed.

[0021]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a left side view of a motorcycle showing an example of a small vehicle to which the present invention is applied.

In FIG. 1, the motorcycle 20 has a vehicle body frame 21, an engine 22 is mounted on the lower front portion of the vehicle body frame 21, a fuel tank 23 is provided above the engine 22, and a fuel tank 23 is provided behind the fuel tank 23. The driving seats 24 are installed respectively. The front portion of the motorcycle 20 is covered with a streamlined cowling 25 to reduce air resistance during traveling and protect the rider from traveling wind pressure.

A head pipe 26 is provided in front of the vehicle body frame 21, and a steering mechanism 27 is provided on the head pipe 26. The steering mechanism 27 is provided with a pair of left and right front forks 29 that rotatably support the front wheels 28.

The front fork 29 is fixed in parallel by the upper bracket 30a and the lower bracket 30b of the steering mechanism 27 so as to sandwich the front wheel 28, while the handlebar 31 and the front fender 32 are provided.
Etc. can be attached. The steering mechanism 27 is pivotally attached to the head pipe 26 so as to be rotatable left and right, and the front wheel 28 is steered by the handle bar 31 so as to be rotatable left and right.

Further, a cowling brace 33 for fixing the cowling 25, which is formed in a frame shape, is provided at the front part of the head pipe 26, and a speedometer 34 or the like is attached to a meter bracket 33b attached to an arm portion 33a of the cowling brace 33. The meters are installed. A headlight assembly 35 having a headlight therein is provided at the front of the cowling brace 33.

On the other hand, a swing arm 37 is pivotally attached to a pivot shaft 36 provided at the lower center of the body frame 21 so as to swing around the pivot shaft 36, and a rear wheel 38 is provided at a rear end of the swing arm 37 and a rear axle 39. Is rotatably supported by. A rear shock absorber 40 and a plurality of links 41 are provided on the base end side of the swing arm 37, and the swing suspension 37, the rear shock absorber 40, and the link 41 constitute a rear suspension mechanism 42.

The engine 22 is composed of a cylinder portion 22a and a case portion 22b, and the rear portion of the case portion 22b is a transmission case 43. An exhaust pipe 44a and a muffler 44b forming an engine exhaust system are connected to the front side of the cylinder portion 22a.
Further, a carburetor 45a and an air cleaner 45b forming an engine intake system are connected to the rear side of the cylinder portion 22a. Further, a radiator 46 that constitutes an engine cooling system is arranged in front of the engine 22.

FIG. 2 is a schematic side view of the lower rear part of the vehicle body, and FIG. 3 is a sectional view taken along the line III-III in FIG.

As shown in FIGS. 1, 2 and 3, the transmission case 43 is provided with a transmission device 48 composed of a plurality of stages of gear trains 47 to reduce rotational power from the engine 22. . An end portion 49 a of a drive shaft 49, which is the final output shaft from the engine 22, projects from the left side surface of the transmission case 43. A drive sprocket 50, which is a drive member, is spline-fitted to the end portion 49a, for example, and the drive sprocket 50 is covered with a sprocket cover 51, which is a cover member, from the outside.

On the other hand, a driven sprocket 52 which is a driven member is mounted integrally with the rear wheel 38 coaxially with the rear axle 39 of the rear wheel 38, and a chain 53 is wound around the driven sprocket 52 and the drive sprocket 50, for example. And power transmission means is configured.

By the way, as another structure of the power transmission means, for example, a drive pulley is used as a drive member, a driven pulley is used as a driven member, and a belt is wound between both pulleys, or a drive gear and a driven member are provided as a drive member. It is conceivable that a driven gear is used and a connecting gear is arranged between both gears.

On the sprocket cover 51, a speed sensor 54, which is a rotation speed detecting means, is detachably attached from the outside of the sprocket cover 51 by a screw or the like (not shown).
Further, the tip of the speed sensor 54 is attached so as to penetrate through the attachment hole 51a of the sprocket cover 51 and project inward. A gasket 55 is interposed between the speed sensor 54 and the sprocket cover 51.

On the other hand, inside the sprocket cover 51, as shown in FIGS. 2 and 3, an outer cylindrical portion 56, which is a bottomed cylindrical rotating member composed of a bottom portion 56a and a peripheral side edge portion 56b, is located outside, as shown in FIG. Is placed so that it opens to the left. A sensor rotor 57, which is another rotating member, is provided inside the outer tubular portion 56. Then, the speed sensor 5 is placed in the space S1 formed by the inner surface 51b of the sprocket cover, the opening side of the outer tubular portion 56, and the sensor rotor 57.
The tip of 4 is stored. And the speed sensor 54
The vehicle speed detection device 58 is configured by the sensor rotor 57 and the sensor rotor 57.

The bottom portion 56a of the outer cylinder portion 56 is integrally fixed to the end portion 49a of the drive shaft 49 by a fixing means such as a bolt 59 and coaxially with the drive shaft 49. The sensor rotor 57, like the outer cylinder portion 56,
It is integrally fixed to the outer cylinder portion 56 coaxially with the drive shaft 49. Further, the side edge portion 56c of the outer cylinder portion 56 is provided so as to extend close to the sprocket cover inner surface 51b.

By the way, the sensor rotor 57 is a disk-shaped member made of a magnetic material such as an iron-based alloy, and as shown in FIGS. Are formed at equal intervals so as to project to the left.

FIG. 5 is a sectional view taken along the line VV of FIG. As shown in FIG. 5, a magnet 60a, a yoke 60b, and a Hall element 60c are provided inside the tip of the speed sensor 54.
A sensor unit 60, which is a magnetic circuit composed of and, is provided so as to face the inner surface of the protrusion 57a of the sensor rotor 57. The Hall element 60c is a magnetoelectric conversion element that converts the amount of magnetism into a voltage by utilizing the Hall effect of the semiconductor, and generates an electromotive force when a magnetic body is placed in the magnetic field generated by the magnet 60a. Further, the amount of magnetism changes depending on the presence or absence of a magnetic substance in the magnetic field, and the electromotive voltage also changes to generate an electric signal (pulse wave). The sensor unit 60 includes a Hall element 60c.
Alternatively, a magnetoresistive element can be used.

That is, when the sensor rotor 57 rotates, the protrusion 57a of the sensor rotor 57 passes near the sensor portion 60 of the speed sensor 54, and a pulse wave is generated depending on the presence or absence of the protrusion 57a. Further, reference numeral 61 is a coupler portion, and the wire harness 62 is connected to the coupler portion 61. The wire harness 62 may be directly connected to the sensor unit 60. As shown in FIG. 2, the wire harness 62 is connected to the speedometer 34 via the arithmetic unit 63 on the way, and is connected to the sensor rotor 57.
The speed of rotation, that is, the vehicle speed is transmitted.

Incidentally, although not shown in detail in the arithmetic unit 63, for example, an amplification circuit for amplifying the pulse wave from the Hall element 60c, a waveform shaping circuit for shaping the signal from this amplification circuit, and a waveform shaping circuit. And a computing unit that computes the vehicle speed based on the signal from.

On the other hand, as shown in FIGS. 2 and 3, on the outer peripheral side of the outer tubular portion 56, a cylindrical member 64 is provided on the inner surface 51b of the sprocket cover so as to extend toward the drive sprocket 50 side. Circumferential edge 56b and cylindrical member 64
A dust seal 65, which is a sealing device, is interposed between the inner peripheral side and the inner peripheral side. The dust seal 65 is a well-known one, and is, for example, a metal annular core material 65a having an L-shaped cross-section and a resilient U-shaped packing member 65b which is coated on one side of the packing member 65b. A freely movable lip portion 65c is formed on the inner peripheral side.

The outer peripheral side of the dust seal 65 is a cylindrical member 64.
While being fitted on the inner peripheral side, the inner peripheral side of the dust seal 65,
That is, the lip portion 65c is loosely fitted to the peripheral side edge portion 56b of the outer tubular portion 56 and is tightened by the garter spring 66.

Next, the operation of this embodiment will be described.

Rotational power of the engine 22 is output by the drive shaft 49 after being decelerated by the transmission 48, transmitted to the rear wheel 38 via the chain 53 and the like, and the outer cylinder portion 56 and the sensor rotor 57 which are rotating members. Is rotated in proportion to the rotation speed of the rear wheel 38, that is, the vehicle speed.

The protruding portion 57a of the rotating sensor rotor 57
Passes through the magnetic field of the sensor portion 60 of the speed sensor 54, which is the rotation speed detecting means, to generate a pulse wave depending on the presence or absence of the protrusion 57a, and the pulse wave is arithmetically processed by the arithmetic unit 63 to the speedometer 34. Display vehicle speed.

It should be noted that if the number of protrusions 57a of the sensor rotor 57 is increased as shown in FIG.
The accuracy of is improved. In addition, the configuration of the vehicle speed detection device 58
As shown in FIGS. 7A and 7B, the outer tubular portion 56 is shared with the sensor rotor 57, and the convex portions 67 are annularly arranged at equal intervals on the bottom portion 56 a of the outer tubular portion 56. Even if the sensor portion 60 is arranged so as to face the convex portions 67, the same effect as that of the above-described embodiment can be obtained.

By the way, inside the sprocket cover 51, the drive sprocket 50 and the chain 5 that rotate at high speed are
There is a risk that foreign matter such as sand, stones, oil, water, and mud will invade by 3 or the like, but as shown in FIG.
The sensor part 60 is covered by the outer cylinder part 56, that is, the bottomed cylindrical outer cylinder part 56 and the inner surface 5 of the sprocket cover.
Since it is located in the space S1 formed by 1b and 1b, foreign matter can be prevented from entering and adhering to the sensor unit 60,
As a result, the accuracy of the vehicle speed detection device 58 can be maintained high.

Further, since the vehicle speed detecting device 58 composed of the speed sensor 54 and the sensor rotor 57 is housed in the space S2 formed by the sprocket cover inner surface 51b and the dust seal 65, the vehicle speed detecting device 58 is connected to the vehicle speed detecting device 58. It is possible to more effectively prevent intrusion and adhesion of foreign matter, particularly water and fine dust, and as a result, the vehicle speed detection device 5
The accuracy of 8 can be maintained even higher.

Further, since the speed sensor 54 is detachably attached from the outside of the sprocket cover 51 with, for example, a screw (not shown), even if foreign matter such as sand iron enters or adheres to the sensor portion 60 or the outer cylinder portion 56. , The speed sensor 54 to the mounting hole 5 of the sprocket cover 51
Foreign matter can be easily removed by simply removing it from 1a.

As described above, the vehicle speed detecting device 58 according to the present invention has a simple structure and the sprocket cover 5 is used.
The change of 1 is also small, and conversion with the conventional mechanical or electric vehicle speed detecting device is possible without much cost.

By the way, the vehicle speed detecting device 58 according to the present invention.
Shows an example in which information from the vehicle speed detecting device 58, that is, the vehicle speed is shown in the speedometer 34. Available.

[0051]

As described above, according to the vehicle speed detecting device for a small vehicle according to the present invention, the final output shaft of the engine is provided with the drive member, and the drive member is covered with the cover member and is separated from the drive member. In a small vehicle that transmits engine output to the rear wheels, a bottomed cylindrical rotating member is provided at the output shaft end, and rotational speed detecting means for the rotating member is arranged inside the cover member, while detecting the rotational speed. Since the means is housed in the space formed by the cover member and the rotating member, it is possible to prevent foreign matter from entering and adhering to the rotation speed detecting means from the outside.
The accuracy of the vehicle speed detection device can be maintained high.

Further, since a cylindrical member is provided inside the cover member on the outer peripheral side of the rotary member, and a sealing device is interposed between the cylindrical member and the rotary member,
It is possible to prevent foreign matter, particularly water and fine dust, from entering and adhering to the rotation speed detecting means from the outside, and as a result, it is possible to maintain the accuracy of the vehicle speed detecting device even higher.

Further, since the rotation speed detecting means is detachably attached from the outside of the cover member, even if foreign matter adheres to the vehicle speed detecting device, this foreign matter can be easily removed.

[Brief description of drawings]

FIG. 1 is a left side view of a motorcycle showing an embodiment of a vehicle speed detecting device for a small vehicle according to the present invention.

FIG. 2 is a schematic side view of a lower rear part of the vehicle body.

FIG. 3 is a sectional view taken along the line III-III in FIG.

FIG. 4 is a plan view of an outer cylinder portion, a sensor rotor, and a sealing device.

5 is a cross-sectional view taken along the line VV of FIG.

FIG. 6 is a plan view showing another embodiment of the sensor rotor.

7A is a plan view showing another embodiment of the vehicle speed detecting device, and FIG. 7B is a sectional view taken along line VII-VII of FIG. 7A.

FIG. 8 is a diagram showing a specific example of a conventional vehicle speed detection device.

9 is a sectional view taken along line XX of FIG.

[Explanation of symbols]

20 Motorcycle (Small Vehicle) 22 Engine 34 Speedometer 49 Drive Shaft (Final Output Shaft of Engine) 49a End of Drive Shaft 50 Drive Sprocket (Drive Member) 51 Sprocket Cover (Cover Member) 51a Speed Sensor Mounting Hole for Sprocket Cover 51b Inner surface of sprocket cover 53 Chain 54 Speed sensor (rotation speed detecting means) 56 Outer cylinder part (rotating member) 56b Peripheral edge of outer cylinder part 57 Sensor rotor (rotating member) 57a Sensor rotor protrusion 58 Vehicle speed detecting device 60 Sensor part of speed sensor 60c Hall element of sensor part 63 Arithmetic device 64 Cylindrical member 65 Dust seal (seal device) S1 Space consisting of sprocket cover inner surface and outer cylinder part S2 Sprocket cover inner surface and seal Space formed by the device

Claims (3)

[Claims] 1. A final output shaft of an engine is provided with a drive member, and the drive member is covered with a cover member and transmits engine output from the drive member to rear wheels. A cylindrical rotating member is provided, and rotation speed detecting means of the rotating member is arranged inside the cover member, and the rotation speed detecting means is housed in a space formed by the cover member and the rotating member. A vehicle speed detection device for a small vehicle characterized by: 2. The small vehicle according to claim 1, wherein a cylindrical member is provided inside the cover member on the outer peripheral side of the rotating member, and a sealing device is interposed between the cylindrical member and the rotating member. Vehicle speed detection device. 3. The vehicle speed detecting device for a small vehicle according to claim 1, wherein the rotation speed detecting means is detachably attached from the outside of the cover member.