WO2012008257A1

WO2012008257A1 - Rotational speed detection device and vehicle speed detection system

Info

Publication number: WO2012008257A1
Application number: PCT/JP2011/063652
Authority: WO
Inventors: 佑貴須山
Original assignee: 日本精機株式会社
Priority date: 2010-07-15
Filing date: 2011-06-15
Publication date: 2012-01-19
Also published as: CN103003138B; JP2012020690A; JP5540961B2; CN103003138A

Abstract

Provided is a rotational speed detection device and a vehicle speed detection system which can be easily mounted to a two-wheeled vehicle. A rotational speed detection device (40a) is provided with: a connection shaft (402) connected to a shaft (340) adapted for connection with the connection shaft (402), the shaft (340) being formed integrally with a driven gear meshing with a gear which rotates as a wheel shaft of the two-wheeled vehicle rotates; and a magnetism detection means (409) for emitting a rotation signal to an instrument as the connection shaft (402) rotates. The shaft (340) is rotatably supported by an extension section (300) of a hub (30), and the connection terminal (405) of the rotational speed detection device (40a) is fitted in a connection hole (302) formed in the extension section (300).

Description

Rotational speed detection device and vehicle speed detection system

The present invention relates to a rotational speed detection device and a vehicle speed detection system used for motorcycles such as motorcycles and bicycles.

The vehicle speed calculation device (instrument) for a motorcycle detects the vehicle speed based on the wheel rotation speed detected by the rotation speed detection device. In the structure of the gear box of the rotational speed detection device that detects the rotational speed of the wheel disclosed in Patent Document 1, the rotation of the gear that rotates together with the wheel is transmitted to the worm gear. The rotation of the worm gear is transmitted to the instrument device by a mechanical cable to detect the vehicle speed. In the mechanical cable, a metal wire is covered with a covering member made of resin or metal, and the wire rotates within the covering member. That is, the mechanical cable transmits the rotation of the worm gear (wheel) to the instrument by the rotation of the wire provided in the mechanical cable.

∙ In the case where the rotation of the wheel is transmitted to the instrument by the mechanical cable, torque load generated between the end on the worm gear side and the end on the instrument side is accumulated in the mechanical cable. For this reason, there existed a possibility that a wire might tear by long-term use.

In recent years, the rotation speed of the worm gear is transmitted to the instrument by the rotation of the wire in the mechanical cable, and the rotation speed of the wheel is detected by a magnetic sensor provided near the wheel, and the detected rotation speed is electrically transmitted to the instrument device. What is transmitted by cable is widespread. With such a configuration, a torque load is not applied to the electric cable that transmits the rotational speed of the wheel to the meter, and it is suitable for long-term use.

For example, in Patent Document 2, a brake drum formed by a brake drum that rotates integrally with a wheel hub and a brake panel fixed to a vehicle body frame so as to close a lateral side opening of the brake drum is provided in a brake chamber. There is disclosed a speed detection device for a motorcycle in which a signal rotating body that rotates together with a drum is disposed and a sensor that detects the rotation speed of the signal rotating body is fixed to the brake panel side.

Further, Patent Document 3 discloses an automatic vehicle equipped with a wheel equipped with a drum brake having a brake drum that opens to one side along the rotational axis and rotates integrally with a wheel hub, and a brake panel that covers the opening of the brake drum. The motorcycle includes a support portion fixed to the wheel hub on the opposite side of the brake panel with respect to the brake drum, a sensor ring fixed to the support portion, and a sensor for detecting a rotation speed of the sensor ring. A wheel speed detection device for a motorcycle is disclosed.

Japanese Utility Model Publication No. 60-1000028 JP-A-6-144328 JP-A-8-133154

However, in the speed detection devices disclosed in Patent Document 2 and Patent Document 3, it is necessary to arrange a tone ring (signal rotating body and sensor ring) that rotates together with the brake drum in the hub. There was a problem that it was difficult.

The present invention has been made in view of such problems, and an object thereof is to provide a rotational speed detection device and a vehicle speed detection system that can be easily attached to a two-wheeled vehicle.

A rotational speed detection device according to a first aspect of the present invention includes:
A rotational speed detection device for detecting a rotational speed of a wheel of a motorcycle,
A connecting member connected to a shaft that rotates integrally with a driven gear that meshes with a gear that rotates as the wheels of the motorcycle rotate.
A rotational speed sensor that converts the rotational speed of the connecting member into an electrical signal and outputs the electrical signal to an external instrument;
A housing for housing the connecting member and the rotation speed sensor, which is attached to a hub located in the center of the wheel;
Is provided.

A vehicle speed detection system according to a second aspect of the present invention is:
The rotational speed detection device;
An instrument for detecting and displaying the speed of the two-wheeled vehicle based on the electrical signal output by the rotational speed detection device;
Is provided.

According to the present invention, it is possible to provide a rotational speed detection device and a vehicle speed detection system that can be easily attached to a motorcycle.

1 is a schematic side view showing a part of a two-wheeled vehicle including a rotation speed detection device according to an embodiment of the present invention. FIG. 2A is an enlarged cross-sectional view of the rotation speed detection device according to the first embodiment. (B) is the figure which looked at the magnet in the arrow direction in the AA cross section of (A). It is an expanded sectional view which shows the example of attachment to the hub of the rotational speed detection apparatus in another example. (A) is an expanded sectional view of the rotational speed detection apparatus which concerns on Embodiment 2. FIG. (B) is a view of the gear member viewed in the direction of the arrow in the BB cross section of (A). FIG. 6 is an enlarged cross-sectional view of a rotation speed detection device according to a third embodiment. FIG. 6 is an enlarged cross-sectional view of a rotation speed detection device according to a fourth embodiment.

Hereinafter, an embodiment of a rotational speed detection device according to the present invention will be specifically described with reference to the accompanying drawings.

<Embodiment 1>
A rotation speed detection device 40a according to the embodiment described below is attached to the wheel 20 portion of the two-wheeled vehicle 10 shown in FIG. More specifically, the rotational speed detection device 40a is attached to an extension portion (attachment portion) 300 in the hub 30 provided at the center of the wheel 20 of the two-wheeled vehicle 10 (rotational

speed detection devices

40b, 40c, and 40d described later). The same applies to.

The hub 30 is formed of a helical gear, and a gear 32 that rotates coaxially with a wheel shaft (not shown) of the wheel 20 as the wheel 20 rotates, and a gear 32 that meshes with the gear 32. A worm gear (driven gear) 34 that rotates in a direction perpendicular to the rotation surface is housed. The hub 30 includes an extending portion 300 that extends from a position facing the worm gear 34 toward the main body of the motorcycle 10 and projects outward from the other surface and is formed in a hollow shape. In the extension part 300 of the hub 30, a connected shaft 340 that is formed integrally with the worm gear 34, is connected to a connecting shaft 402 of a rotational speed detection device 40 a described later, and is rotatably supported by a bearing 301; A part of a connecting shaft (connecting member) 402 of a rotational speed detecting device 40a described later is accommodated. The coupled shaft 340 is not formed integrally with the worm gear 34 but may be formed separately, and rotates (integrally) in synchronization with the rotation of the worm gear 34. If it is. The worm gear 34 is disposed in the drum brake 306 of the wheel 20.

Although details will be described later, the rotational speed detection device 40a detects the change in the magnetic field accompanying the rotation of the coupling shaft 402 coupled to the coupled shaft 340, and detects the electrical signal (this embodiment) In the form, it is detected by converting it into a square wave pulse signal) and outputting it. The rotational speed of the wheel 20 is the same as or constant with the rotational speed of the coupled shaft 340 by the gear 32 and the worm gear 34. Therefore, the rotational speed of the coupled shaft 340 is detected by detecting the rotational speed of the wheel 20. It can also be said. That is, the rotational speed detection device 40a (the same applies to 40b, 40c, and 40d described later) detects the rotational speed of the wheel 20. The converted pulse signal is a signal having a period corresponding to the rotational speed of the connected shaft 340 (and the connecting shaft 402), and is sent from the rotational speed detection device 40a to the meter 50 via the cable. The instrument 50 calculates (detects) the vehicle speed based on the pulse signal supplied from the rotational speed detection device 40 a and displays the calculated vehicle speed on the display unit 500 provided in the instrument 50. As described above, since the cycle of the pulse signal is related to the rotational speed of the wheel 20, and the rotational speed of the wheel 20 is related to the traveling speed of the two-wheeled vehicle, the two-wheeled vehicle travels based on the cycle of the pulse signal. The speed is easily calculated. By counting the number of pulse signals for one rotation (a known value) for one cycle and dividing the outer circumference of the wheel by the time required for this counting, the vehicle speed of the motorcycle 10 is calculated. Is done. A vehicle speed detection system that includes the instrument 50 and the rotational speed detection device 40 a and detects the vehicle speed of the two-wheeled vehicle 10 is configured.

Next, the structure of the rotation speed detection device 40a will be specifically described with reference to FIG. The rotational speed detection device 40a includes a magnet (rotating body) 406, a connecting shaft 402 having a connecting portion 404 at one end and a magnet 406 fixed to the other end, a substrate 408, and a magnet 406 placed on the substrate 408. A magnetic detection means (signal output means) 409 for detecting a change in magnetism, a wiring means 420, a magnet 406, a part of the connecting shaft 402, a substrate 408, a magnetic detection means 409, and a part of the wiring means 420 are accommodated. Housing 400. The housing 400 only needs to store at least a part of each member. In the present embodiment, the magnetic detection means 409 and the magnet 406 constitute a rotational speed sensor that converts the rotational speed of the connecting shaft 402 into an electrical signal and outputs it to the instrument 50.

The connecting shaft 402 is rotatably supported by a bearing 401 provided between the housing 400 and the housing 400 described later. One end of the connection shaft 402 protrudes from the connection end (insertion portion) 405 of the housing 400, and a magnet 406 is fixed to the other end of the connection shaft 402. The connecting portion 404 provided at one end of the connecting shaft 402 is composed of a groove formed in a straight line. A coupled portion 342 made of a linearly formed protrusion is formed at the end of the coupled shaft 340 provided in the extending portion 300. The connecting portion 404 is connected to the connected portion 342. The relationship between these males and females may be reversed. In other words, the connected portion 342 may be in the shape of a connecting portion 404 formed of a groove formed in a straight line, and the connecting portion 404 may be in the shape of a connected portion 342 formed of a protrusion formed in a straight line. Further, the connecting portion 404 may have a shape that can be connected in conformity with the shape of the connected portion 342 even when the shape of the connected portion 342 is not a linear groove shape.

As shown in FIG. 2, the magnet 406 is made of a thick cylindrical ferrite magnet, and is arranged radially from the axis serving as the rotation center (the rotation axis of the connecting shaft 402), that is, along the rotation direction of the magnet 406. And having a plurality of magnetic poles having different polarities (S pole and N pole) alternately (plane multipole magnetization). The magnets 406 are alternately magnetized every 45 ° around the axis, and four S poles and four N poles are alternately arranged. The magnet 406 will be described as having magnetic poles alternately magnetized every 45 °, but the present invention is not limited to this embodiment. For example, the magnet 406 is alternately magnetized every 22.5 °, and S A magnet in which eight poles and N poles are alternately arranged may be used.

The magnetic detection means 409 is composed of a Hall element, is disposed at a predetermined position on the substrate 408 so as to face one of the magnetic poles of the magnet 406, and is electrically connected to the wiring means 420. The magnetic detection unit 409 detects a change in the magnetic field of the rotating magnet 406. The magnetic detection means 409 outputs a pulse signal having a period corresponding to the change in the magnetic field (according to the rotation speed of the connecting shaft 402), and the pulse signal is transmitted via the wiring means 420 disposed in the cable 42. Is transmitted to the instrument 50.

The housing 400 supports the connecting shaft 402 via the bearing 401. The housing 400 is on one end side of the coupling shaft 402 and has a connection end 405 formed to be narrower than other portions. The housing 400 is attached to the extension portion 300 of the hub 30 by fitting the connection end 405 into the connection hole 302 formed in the extension portion 300. Furthermore, a locking groove (concave portion) 403 that is locked to a locking screw (fixing member) 303 is formed on a part of the outer periphery of the connection end 405. A screw hole 304 that communicates with the connection hole 302 and the outside is formed in the extension portion 300 on the extension of the tangent line of the locking groove 403 in a direction orthogonal to the connection hole 302. When the locking screw 303 is screwed into the screw hole 304 from the outside, the locking screw 303 is disposed in a part of the locking groove 403. By doing in this way, even if force is applied to the rotational speed detection device 40a in the direction to be removed from the hub 30, the portion that forms the locking groove 403 contacts (engages) the locking screw 303, The housing 400 of the rotation speed detection device 40a is prevented from being removed from the connection hole 302. That is, the connection between the hub 30 and the rotation speed detection device 40a is maintained.

Next, the vehicle speed detection function of the rotational speed detection device 40a configured as described above will be described. When the wheel 20 rotates, the gear 32 rotates with the wheel 20 via the wheel shaft. Simultaneously with the rotation of the gear 32, the worm gear 34 meshing with the gear 32 and the connected shaft 340 rotating integrally with the worm gear 34 are rotated. At the same time as the connected shaft 340 rotates, the connecting shaft 402 rotates in synchronization (integrally) with the connected shaft 340 via the connecting portion 404 connected to the connected portion 342 of the connected shaft 340. At the same time, the magnet 406 formed on the connection shaft 402 rotates integrally with the connection shaft 402 in synchronization with the connection shaft 402. The magnetic detection means 409 detects a change in the magnetic field due to the switching of the polarity of the opposing magnetic poles of the magnet 406, and sends a pulse signal corresponding to the change in the magnetic field via the wiring means 420 provided in the cable 42. Transmit to the instrument 50. The instrument 50 calculates the vehicle speed according to the period of the signal, and displays the calculated vehicle speed on the display unit 500.

In addition, the to-be-connected shaft 340 provided in the extension part and the extension part 300 is the same structure as what is connected to the mechanical cable which is a prior art for detecting the rotational speed of a wheel. That is, the rotational speed detection device 40a is easily attached to the hub 30 having the conventional extending portion 300 and the connected shaft 340.

In addition, the rotational speed detection device 40a according to the present embodiment can be attached and detached without removing the wheel from the suspension of the two-wheeled vehicle 10, and replacement from a mechanical cable and other maintenance are easy. is there.

(Modification)
The rotational speed detection device 40a according to this embodiment of the present invention is not limited to the above-described embodiment. For example, as shown in FIGS. 1 and 2, the rotation speed detection device 40 a is attached to the extension portion 300 of the hub 30 by locking (engaging) the locking screw 303 with the locking groove 403 of the housing 400. Although it demonstrated as what is latched so that it may not pull out, it is not limited to this structure.

Another example will be specifically described with reference to FIG. A female screw (threaded portion) 307 is formed on the inner surface of the connection hole 302 provided at the end portion of the extension portion 300 of the hub 30 with a predetermined length from the end portion. In the housing 400, a male screw (screwed portion) 407 that is screwed into the female screw 307 is formed on the outer surface of the connection end 405. The male screw 407 is disposed at a predetermined position on the base end side with respect to the side inserted into the connection hole 302 in the connection end 405 and is formed so as to protrude from the other outer surface. The diameter of the other outer surface with respect to the site | part in which the external thread 407 in the connection end 405 is formed is formed so that it may correspond with the internal diameter of the connection hole 302 substantially.

Next, the connection between the rotational speed detection device 40a having the above-described configuration and the extending portion 300 of the hub 30 will be described. First, the orientation of the connecting shaft 402 is adjusted so that the protruding connected portion 342 and the groove-like connecting portion 404 are fitted (connected). Next, the connection end 405 formed in the housing 400 of the rotational speed detection device 40 a is inserted into the connection hole 302 of the extension part 300. The connecting end 405 is inserted to a position where the connected portion 342 and the connecting portion 404 are fitted (connected), and the side surface of the male screw 407 and the side surface of the female screw 307 abut, and the housing 400 is rotated to rotate the rotation speed. The detection device 40a and the hub 30 are screwed together. At this time, since the connecting shaft 402 is rotatably supported by the bearing 401 on the inner surface of the housing 400, the connecting shaft 402 does not receive the rotational torque of the housing 400 when screwed. Therefore, no rotational resistance is generated by the coupled shaft 340 fitted to the coupling shaft 402 that receives the rotational torque, and the rotational speed detection device 40a is smoothly screwed to the hub 30.

Further, the male screw 407 is disposed at a predetermined position on the base end side with respect to the side inserted into the connection hole 302 in the connection end 405, so that the coupled portion 342 and the coupling portion 404 are fitted to each other. Until the connecting shaft 402 is inserted, the connecting shaft 402 can be prevented from rotating by screwing of the male screw 407 and the female screw 307, and the connecting portion 404 and the connected portion 342 can be suitably connected. The posture of the shaft 402 can be maintained.

As described above, the rotational speed detection device 40a may be prevented from being detached from the hub 30 by screwing.

<Embodiment 2>
Next, the rotation speed detection device 40b according to the second embodiment will be described with reference to FIG. Note that, in the description of the following embodiments, for the sake of easy understanding, the description of the contents overlapping with the above description (such as the description of the members having the same reference numerals in the above description) is omitted.

The rotational speed detection device 40b includes a gear member (rotary body, uneven member) 410, a connecting shaft 402 having a connecting portion 404 at one end and a gear member (rotating body, uneven member) 410 fixed to the other end, and a substrate. 412, a magnet 414 that is placed on the substrate 412 and forms a magnetic field with the gear member 410, a magnetic detection means 416 placed on the magnet 414, a wiring means 420, a gear member 410, a connection A housing 400 that houses a part of the shaft 402, a substrate 412, a magnet 414, a magnetic detection means 416, and a part of the wiring means 420. In this embodiment, the magnet 414 and the magnetic detection means 416 constitute a signal output means, and these and the gear member constitute a rotational speed sensor.

The gear member 410 is made of a magnetic material, and, as shown in FIG. 4, on the side facing the magnetic detection means 416, the gear member 410 is radiated from the axis serving as the center of rotation (the rotation axis of the coupling shaft 402), that is, The concave portions 411a and the convex portions 411b are alternately arranged along the rotation direction. The concave portions 411a and the convex portions 411b of the gear member 410 are alternately formed every 45 °, and a total of four concave portions 411a and convex portions 411b are arranged. Note that the gear member 410 is described as having the recesses 411a and the protrusions 411b alternately every 45 °, but the present invention is not limited to this embodiment, and for example, the recesses and the protrusions alternately every 22.5 °. There may be a gear member formed with a total of eight portions.

The gear member 410 is coaxial with the connecting shaft 402 and rotates integrally in synchronization therewith. When the magnet 414 faces the recess 411a of the gear member 410, the distance between the magnets 414 becomes relatively long, and a weak magnetic field is generated. On the other hand, when the magnet 414 faces the convex portion 411b of the gear member 410, the distance between the magnets 414 is relatively short, and thus a strong magnetic field is generated.

The magnetic detection means 416 includes a Hall element, and detects a change in the magnetic field between the magnet 414 and the gear member 410. The magnetic detection means 416 transmits a pulse signal corresponding to the strength of the magnetic field to the meter 50 via the wiring means 420 disposed in the cable 42.

In the rotational speed detection device 40b according to the second embodiment configured as described above, the magnetic detection means 416 has a magnetic field when the magnet 414 is opposed to the concave portion 411a of the gear member 410 rotating, and when it is opposed to the convex portion 411b. An electrical signal (pulse signal) having a period corresponding to the period of change in the intensity (rotation speed of the connecting shaft 402) is transmitted to the meter 50 through the wiring means 420 disposed in the cable 42. The meter 50 calculates the vehicle speed based on the pulse signal supplied from the magnetic detection means 416 to the meter 50 during the continuous rotation of the gear member 410. The handling of the pulse signal is substantially the same as in the first embodiment. In such an embodiment, the magnet 414 has a simple structure, and the rotational speed detection device 40b can be formed at low cost.

<Embodiment 3>
Next, a rotation speed detection device 40c according to Embodiment 3 will be described with reference to FIG. The rotational speed detecting device 40c includes a magnet (rotating body) 406, a connecting shaft 402 having a connecting portion 404 at one end and a magnet 406 fixed at the other end, and four legs 426b facing the magnet 406. A core rod made of a magnetic material sandwiched between a first yoke 426, a second yoke 428 having four legs 428b facing the magnet 406, and the first yoke 426 and the second yoke 428 and around which the coil 424 is wound. 422, coil 424, wiring means 420, magnet 406, part of connecting shaft 402, first yoke 426, second yoke 428, core rod 422, coil 424, and housing 400 that covers part of wiring means 420. And comprising. In this embodiment, the first yoke 426, the second yoke 428, and the core rod 422 constitute a yoke from the vicinity of the magnet 406 to the inside of the coil 424, and this yoke and the coil 424 constitute a signal output means. The rotation speed sensor is configured by the signal output means and the magnet 406.

The first yoke 426 includes a disk-shaped yoke body 426a and four legs 426b extending from the circumferential surface of the yoke body 426a to a position facing the circumferential surface of the magnet 406, and is made of a magnetic material.

Four legs 426b extend from the peripheral surface of the yoke body 426a at intervals of 90 ° around the axis of the magnet 406, respectively. On the other hand, as described above, the magnets 406 are formed to have different polarities alternately in a radial pattern (alternately magnetized every 45 °). That is, the four legs 426b always face the rotating magnet 406 with the same polarity magnetic pole.

The second yoke 428 includes a disk-shaped yoke body 428a and four legs 428b extending from the circumferential surface of the yoke body 428a to a position facing the circumferential surface of the magnet 406, and is made of a magnetic material.

Four legs 428b extend from the peripheral surface of the yoke body 426a at intervals of 90 ° around the axis of the magnet 406, respectively. On the other hand, as described above, the magnets 406 are formed to have different polarities alternately in a radial pattern (alternately magnetized every 45 °). That is, the four legs 428b always face the rotating magnet 406 with the same polarity magnetic pole. The leg 428b is disposed at a position shifted by 45 ° around the axis of the magnet 406 with respect to the leg 426b. That is, the leg 426b and the leg 428b are opposed to different magnetic poles in the magnet 406, respectively. For this reason, the first yoke 426 and the second yoke 428 have different polarities.

The core rod 422 and the coil 424 wound around the core rod 422 are sandwiched at both ends in the axial direction by the yoke body 426a of the first yoke 426 and the yoke body 428a of the second yoke 428. The coil 424 is connected to the wiring means 420.

In the rotational speed detection device 40c according to the third embodiment configured as described above, when the leg 426b faces the south pole of the rotating magnet 406 (when the leg 428b faces the north pole of the magnet 406), the coil 424 is used. The magnetic lines of force (through the core rod 422) are directed from the yoke body 426a side to the yoke body 428a side. An electromotive force is generated by the magnetic field lines. Further, when the leg 426b faces the north pole of the rotating magnet 406 (when the leg 428b faces the south pole of the magnet 406), the magnetic lines of force in the coil 424 are directed from the yoke body 428a side to the yoke body 426a side. It will be. This line of magnetic force generates an electromotive force that is reversed from the previous electromotive force. In the continuous rotation of the magnet 406, a sin wave current (electric signal) for four cycles per rotation is transmitted via the wiring means 420 disposed in the cable 42 in accordance with the magnitude and direction of the electromotive force. It will be supplied to the instrument 50. The meter 50 forms a sin wave-like current supplied to the meter 50 into a square wave (which is handled in the same manner as the pulse signal), and calculates the vehicle speed. Thus, in this embodiment, an electromotive force is generated in the coil 424 due to a change in the magnetic field of the yoke due to the rotation of the magnet 406, and a current flowing according to the electromotive force is output to the meter 50 as an electrical signal. Thus, the rotation speed of the connecting shaft 402 is output as an electrical signal. In such an embodiment, since the signal output means is constituted by the coil and the yoke, the rotational speed detecting device 40c can be formed at low cost.

<Embodiment 4>
Next, a rotational speed detection device 40d according to Embodiment 4 will be described with reference to FIG. The rotational speed detection device 40d includes a gear member (rotary body, uneven member) 410, a coupling shaft 402 having a coupling portion 404 at one end and a gear member 410 fixed at the other end, and a magnetic field between the gear member 410. Forming a magnet 430, a coil 434 fixed on the magnet 430, and a coil 434 made of a magnetic material, a coil 434 through which the yoke 432 passes, wiring means 420, a gear member 410, and a connecting shaft 402. A housing 400 that covers a part of the magnet 430, the yoke 432, and a part of the wiring means 420. In the present embodiment, the magnet 430, the yoke 432, and the coil 434 constitute a signal output means, and the signal output means and the gear member 410 constitute a rotational speed sensor.

The magnet 430 is fixed in the housing 400. When the magnet 430 faces the recess 411a of the gear member 410 that rotates coaxially with the connecting shaft 402, a weak magnetic field is generated because the distance therebetween is relatively long. On the other hand, when the magnet 430 faces the convex portion 411b of the gear member 410, the distance between them becomes relatively short, and thus a strong magnetic field is generated.

The strength of the magnetic force passing through the yoke 432 is proportional to the strength of the magnetic field between the magnet 430 and the gear member 410. An electromotive force is generated in the coil 434 according to the strength of the magnetic force passing through the yoke 432. A sin-wave current is transmitted to the instrument 50 through the wiring means 420 according to the magnitude of the electromotive force generated in the coil 434.

In the rotational speed detection device 40d according to the fourth embodiment configured as described above, the magnet 430 corresponds to the strength of the magnetic field when facing the concave portion 411a of the rotating gear member 410 and when facing the convex portion 411b. An electromotive force is generated in the coil 434. In continuous rotation of the gear member 410, a sin-wave current (electric signal) for four cycles per rotation is measured via the wiring means 420 disposed in the cable 42 in accordance with the magnitude of the electromotive force. 50. The meter 50 shapes the supplied sin-wave current into a square wave (handling is substantially the same as that of the pulse signal), and calculates the vehicle speed. Thus, in this embodiment, an electromotive force is generated in the coil 434 due to a change in the magnetic field of the yoke due to the rotation of the gear member 410, and a current that flows in accordance with the electromotive force is output to the meter 50 as an electrical signal. Thereby, the rotational speed of the connecting shaft 402 is output as an electrical signal. In such an embodiment, the magnet 430 has a simple structure, and the rotational speed detection device 40b can be formed at low cost.

The vehicle speed can be detected by the rotational speed detection device 40 (40a to 40d) according to the above-described embodiment. In the rotational speed detection device 40 according to any of the first to fourth embodiments, the wheel from the suspension of the two-wheeled vehicle 10 can be used. The rotational speed detection device 40 can be attached and detached without removing the cable, and replacement from the mechanical cable and other maintenance can be easily performed.

The present invention is not limited to the above-described embodiment (also including the configuration described in the drawings). Needless to say, it is possible to appropriately change the above configuration.

It should be noted that a vehicle having a drum brake is suitable for mounting the rotational speed detection device according to the present invention because it includes a gear that rotates as the wheel shaft rotates and a worm gear that meshes with the gear.

In addition, since the rotational speed sensor of the rotational speed detection apparatus according to the present invention is housed in the housing and is not exposed to the outside, the rotational speed sensor may be defective due to foreign matters such as sand, pebbles, and rainwater. Can be prevented.

The present invention can be used in a rotational speed detection device and a vehicle speed detection system used for motorcycles such as motorcycles and bicycles.

10 motorcycle
20 wheels
30 hub
300 Extension part (attachment part)
301 Bearing
302 Connection hole
303 Locking screw (fixing member)
304 Screw hole
306 Brake drum
307 Female thread (threaded part)
32 gear
34 Worm gear (driven gear)
340 Connected shaft
342 Connected part
40 (40a, 40b, 40c, 40d) Rotational speed detection device 400 Housing 401 Bearing
402 Connection shaft (connection member)
403 Locking groove (concave)
404 connection part 405 connection end (insertion part)
406 Magnet (Rotating body)
407 Male thread (threaded part)
408 substrate
409 Magnetic detection means (signal output means)
410 Gear member (rotary body, uneven member)
411a recess
411b Convex part
414 Magnet
416 Magnetic detection means
42 cable
420 Wiring means
424 coil
426 1st yoke
428 2nd yoke
430 Magnet
432 York
434 Coil
50 meter

Claims

A rotational speed detection device for detecting a rotational speed of a wheel of a motorcycle,
A connecting member connected to a shaft that rotates integrally with a driven gear that meshes with a gear that rotates as the wheels of the motorcycle rotate.
A rotational speed sensor that converts the rotational speed of the connecting member into an electrical signal and outputs the electrical signal to an external instrument;
A housing for housing the connecting member and the rotation speed sensor, which is attached to a hub located in the center of the wheel;
A rotational speed detection device comprising:
The rotational speed sensor includes a rotating body that rotates as the connecting member rotates, and a signal output unit that converts the rotating speed of the rotating body into the electrical signal and outputs the electrical signal to the instrument.
The rotational speed detection apparatus according to claim 1, wherein
The rotating body includes a magnet in which a plurality of magnetic poles are arranged along a rotation direction of the rotating body,
The signal output means converts the change in the magnetic field of the magnet that occurs at a predetermined position by the rotation of the rotating body into the electrical signal and outputs it to the instrument.
The rotational speed detection apparatus according to claim 2, wherein
The rotating body includes an uneven member in which unevenness is arranged along a rotation direction of the rotating body,
The signal output means includes a magnet facing the concavo-convex member, converts a change in the magnetic field between the concavo-convex member and the magnet generated at a predetermined position by the rotation of the rotating body into the electric signal, and Output to the instrument,
The rotational speed detection apparatus according to claim 2, wherein
The rotating body includes a magnet in which a plurality of magnetic poles are arranged along a rotation direction of the rotating body,
The signal output means includes a coil and a yoke extending from the vicinity of the magnet into the coil,
An electromotive force is generated in the coil due to a change in the magnetic field of the yoke due to the rotation of the rotating body, and a current flowing according to the electromotive force is output to the instrument as the electrical signal.
The rotational speed detection apparatus according to claim 2, wherein
The rotating body includes an uneven member in which unevenness is arranged along the rotation direction,
The signal output means includes a magnet facing the concavo-convex member, a yoke positioned between the concavo-convex member and the magnet, and a coil through which the yoke passes.
An electromotive force is generated in the coil due to a change in the magnetic field of the yoke due to the rotation of the rotating body, and a current flowing according to the electromotive force is output to the instrument as the electrical signal.
The rotational speed detection apparatus according to claim 2, wherein
The hub includes a mounting portion surrounding the shaft,
The housing is attached to the hub by a part of which is screwed with the attachment portion.
The rotation speed detection device according to claim 1, wherein the rotation speed detection device is a rotation speed detection device.
The hub includes a mounting portion surrounding the shaft,
The housing includes an insertion portion that is inserted into the attachment portion;
The insertion portion includes a concave portion in which the housing is fixed to the hub by engaging with a fixing member inserted through the attachment portion.
The rotation speed detection device according to claim 1, wherein the rotation speed detection device is a rotation speed detection device.
The driven gear is disposed in a brake drum disposed in the hub;
The rotation speed detection device according to claim 1, wherein the rotation speed detection device is a rotation speed detection device.
The rotational speed detection device according to any one of claims 1 to 9,
An instrument for detecting and displaying the speed of the two-wheeled vehicle based on the electrical signal output by the rotational speed detection device;
A vehicle speed detection system comprising: