JP4683331B2 - Rotation detector - Google Patents

Description

  The present invention relates to a rotation detection device, for example, a rotation detection device for a motorcycle such as a motorcycle or a bicycle.

  A rotation detection device is disclosed in Patent Document 1. This rotation detection device is a Hall IC mounted on a circuit board on a substantially cylindrical resin case having a detection surface for detecting a detection target. And a magnet is arranged along the detection surface, and the circuit board, the magnetic detection element, and the magnet are sealed with a sealing member made of epoxy or the like. Yes. When this rotation detection device is used as a rotation detection device for a motorcycle (for example, a motorcycle), the rotation detection device is attached to a vehicle mission case, a sprocket cover, etc., and a transmission gear, a sprocket, etc. rotating inside it are detected. It is common to detect as a body.

  When such a rotation detection device is used to detect a transmission gear, a sprocket, or the like as a detected body, there is some clearance in the detected body, so that the body rigidity of the vehicle (two-wheeled vehicle), the displacement, etc. Since the detection object vibrates and the detection position gap between the detection object and the rotation detection device fluctuates, a magnetic change occurs in the rotation detection device, resulting in detection noise. Depending on the output data to be output, for example, there is a problem that it may cause a malfunction of the indicating instrument that displays the speed. Focusing on this problem, the applicant of the present application has proposed a rotation detection device disclosed in Patent Document 2.

  The rotation detection device is attached to a front wheel (wheel) of a motorcycle such as a motorcycle, and includes a housing having an insertion portion through which an axle to which the front wheel wheel is attached is inserted, and the front wheel is provided in the insertion portion. A magnetic object that has a plurality of magnetic poles that rotate with the wheel and that is made of a magnetic medium such as a plastic magnet is mounted. It is a structure to do.

  The object to be detected is formed by integrally forming a cylindrical portion having the magnetic pole and a rotation transmitting piece for transmitting rotation of the front wheel to the cylindrical portion by a plastic magnet or the like. The rotation transmission piece is formed to be drawn outward from the cylindrical portion on the opening side of the housing so as to correspond to a concave-shaped mounting portion provided on the hub of the front wheel. It is provided at a plurality of locations on the periphery.

The rotation detection device having such a configuration is disposed in a state of being sandwiched between the front wheel and the front fork. That is, the rotation detecting device inserts the axle on which the front wheel is mounted into the insertion portion, and inserts the rotation transmission piece into the attachment portion provided on the hub of the front wheel, By fixing the axle projecting outward from the housing with a nut member via the front fork, the front wheel and the front fork are sandwiched (co-tightened) Arranged.
JP-A-2-264817 JP-A-9-229714

  When the rotation detection device is attached to the hub, the detected object is rotatably inserted into the insertion portion of the housing. Therefore, the rotation transmission piece of the rotation detection device is attached to the attachment portion of the hub. When fitting, only the object to be detected may rotate, and the rotation transmission piece may not fit into the mounting part, and it is confirmed visually whether or not the rotation transmission piece fits into the mounting part. Is difficult. Accordingly, when the rotation detection device is fastened between the hub and the front fork in an inappropriate state where the rotation transmission piece is not fitted into the mounting portion, the rotation transmission constituted by the plastic magnet is performed. There was a problem that breakage of the piece might occur.

  The present invention pays attention to the above-mentioned problems, and provides a rotation detection device capable of preventing damage to a detected object and assembling the rotation detection device to a wheel hub.

The present invention comprises a housing provided between a hub and a front fork of the wheel provided with an insertion portion through which an axle on which a wheel of a motorcycle is mounted is inserted, and a magnet that generates a magnetic field disposed in the housing. A rotation detection device comprising at least a magnetic detection body disposed in the housing in a state in which the change of the magnetic field can be detected and detecting the change of the magnetic field accompanying the rotation of the detection target, Is formed of a magnetic material different from that of the hub and includes at least a detected portion that rotates in synchronization with the hub, and the detected portion is positioned around the insertion portion so as to be separated from the insertion portion. It comprises a plurality of plate-like projecting pieces .

  According to the present invention, the detected object includes a support part that supports the detected part with a hole part through which the insertion part is inserted, and a rotation transmission part that transmits the rotation of the hub to the support part. It is characterized by becoming.

  Further, the present invention is characterized in that the support portion includes a recess that is the rotation transmission portion that fits into a protrusion provided on the hub.

  Further, the present invention is characterized by comprising a pair of raised portions fixed to the concave portion with the protruding portion interposed therebetween.

  Further, the present invention is characterized in that a convex portion which is the rotation transmitting portion fitted to a concave-shaped arrangement portion provided on the hub is provided.

  In the invention, it is preferable that the housing includes a storage portion for allowing the detected portion to be close to the magnetic detection body and for rotatably storing the detected portion.

  The present invention comprises a housing provided between a hub and a front fork of the wheel provided with an insertion portion through which an axle on which a wheel of a motorcycle is mounted is inserted, and a magnet that generates a magnetic field disposed in the housing. A rotation detection device comprising at least a magnetic detection body disposed in the housing in a state in which the change of the magnetic field can be detected and detecting the change of the magnetic field accompanying the rotation of the detection target, However, it is formed of a magnetic material different from that of the hub, and includes at least a detected portion that rotates in synchronization with the hub, thereby preventing damage to the detected body and providing the rotation detecting device with the wheel hub. It becomes possible to assemble to.

  Hereinafter, a case where an embodiment of the present invention is applied to, for example, an electric rotation detection device that detects the number of rotations of a motorcycle (two-wheeled vehicle) will be described with reference to the accompanying drawings.

  1 to 3, the rotation detection device A includes a housing 1, a circuit board 2, a magnetic detection element (magnetic detection body) 3, a seal member 4, and a detection target 5.

  The housing 1 is made of a resin material such as polybutylene terephthalate or polyamide, and an axle S on which a front wheel (wheel) of a two-wheeled vehicle is mounted is inserted in a substantially center of the housing 1 to form a substantially cylindrical shape made of a metal material. The insertion part 1a is insert-molded. At the periphery of the insertion portion 1a, a first storage portion (storage portion) for rotatably disposing (accommodating) a detected portion 5a of the detection target 5 described later in detail on the outer periphery of the insertion portion 1a. 1b is formed, and a second storage portion 1c in which a fixing portion 5c of the detection object 5 described later is rotatable is formed at a position continuous from the first storage portion 1b via a stepped portion. A third storage portion 1d in which a seal member 4 which will be described in detail later is disposed is formed at a position continuous from the second storage portion 1c via a stepped portion. Further, on one outer side from the first storage part 1b, there is a fourth storage part 1e for storing the circuit board 2, the magnetic detection element 3 mounted on the circuit board 2, the magnet 3a for generating a magnetic field, and the holder 3b. Is formed. The insertion portion 1a may be a synthetic resin material made of polyphenylene sulfide (PPS) instead of a metal material.

  The circuit board 2 has a predetermined wiring pattern formed on a substrate made of an insulating material such as glass epoxy, and an electronic component (not shown) made of a magnetic detection element 3 and a capacitor is electrically fixed by solder or the like. . Further, the circuit board 2 is provided with a holder 3b that holds a magnet 3a located behind the magnetic detection element 3. Further, the circuit board 2 is provided with a wiring cord (not shown) for supplying power to the magnetic detection element 3 and transmitting an output signal from the magnetic detection element 3 to an indicator (not shown) (for example, a speedometer). The wiring cord is electrically connected to a predetermined portion of the circuit board 2 by soldering. The circuit board 2 is disposed and fixed by filling the fourth housing portion 1e with a sealing member 6 made of epoxy resin or the like after being disposed in the fourth housing portion 1e.

  The magnetic detection element 3 is composed of a Hall IC, an MR element (semiconductor magnetoresistive element), etc., and detects a change in the magnetic field accompanying the movement (rotation) of the detected object 5.

  The seal member 4 is made of a rubber material such as nitrile or silicon, and the seal member 4 has a thin donut shape. Since the outer shape of the seal member 4 is slightly larger than the side wall of the third storage portion 1d of the housing 1, the seal member 4 is disposed and fixed to the third storage portion 1d by press fitting. Therefore, when the rotation detection device A is disposed on the hub 10a (attachment portion) of the front wheel wheel 10 made of aluminum, the outer surface of the cylindrical portion 10b of the hub 10a and the inner surface of the seal member 4 are brought into contact with each other. 1 prevents dust, dirt or moisture from entering the inside.

  On the end surface of the cylindrical portion 10b of the hub 10a, a protruding portion 10c is provided at a point-symmetrical position about the rotation center of the hub 10a. The projecting portion 10c has a circular cross section in the direction perpendicular to the rotation axis of the hub 10a. A ball bearing 11 is provided as a bearing in the space inside the cylindrical portion 10b of the hub 10a.

  The detection object 5 is made of a magnetic material having a magnetic property, for example, a metal material such as iron, and is made of a plate-like protruding piece having an arcuate cross-sectional shape spaced apart from the periphery of the insertion portion 1 a of the housing 1. A detection unit 5a is provided. The detected body 5 includes a substantially annular plate-shaped support portion (base portion) 5b for supporting the detected portion 5a on the lower end side of the detected portion 5a. A hole 5b1 through which the axle shaft S and the insertion portion 1a are inserted is formed in a substantially central portion of the base portion 5b. In the case of the present embodiment, the detected body 5 includes a detected portion 5 a and a base portion 5 b that are integrally formed, and the detected portion 5 a is disposed near the magnetic detection element 3. For example, it is desirable to set the distance between the detected portion 5a and the magnetic detection element 3 within 5 mm. In the present embodiment, two detected parts 5a are provided in order to generate two pulses by one rotation of the hub 10a. Note that when the hub 10a generates four pulses per rotation, the number of detected portions 5a is four. When the hub 10a generates n pulses per rotation, the n detected portions 5a may be provided.

  Further, the base portion 5b is formed with a concave portion 5c fixed to a protruding portion 10c formed at the end portion of the cylindrical portion 10b of the hub 10a of the front wheel 10. The concave portion 5c functions as a rotation transmitting portion for transmitting the rotation of the hub 10a to the base portion 5b, and has a size substantially equal to that of the protruding portion 10c of the hub 10a on the outer peripheral portion of the base portion 5b. Consisting of notches, the opposing sides of the notches are provided with raised portions 5d that are raised so as to come into contact with the side surfaces of the protruding portions 10c, and at the pair of raised portions 5d, By sandwiching the protruding portion 10c, the detected body 5 is fixed to the hub 10a, and the detected portion 5a is rotated in synchronization with the rotation of the hub 10a. The detection object 5 is firmly fixed to the hub 10a so that the detection object 5a is not easily detached from the hub 10a. And when fixing the to-be-detected part 5a to the hub 10a, the recessed part 5c of the to-be-detected body 5a will be pushed in (press-fit) while applying pressure to the protrusion part 10c, and will be fixed.

  In the present embodiment, the pair of raised portions 5d provided on the inner side surface of the recess 5c is in contact with the surface of the protruding portion 10c with respect to the rotation direction of the hub 10a, so that the detected object 5 is fixed to the hub 10a. However, the present invention is not limited to this embodiment, and for example, at least one raised portion 5d may be provided on the bottom surface of the recess 5c, and the detected object 5 may be press-fitted and fixed to the hub 10a.

  The rotation detection device A is assembled to the hub 10a by positioning and fixing the recess 5c of the detected body 5 to the protrusion 10c provided at the end of the hub 10a so as not to move in the rotation direction of the hub 10a. Keep it. Then, the housing 1 of the rotation detecting device A is assembled to the cylindrical portion 10b of the hub 10a while the sealing member 4 is bent, and finally, the housing 10 is fixed between the hub 10a and a front fork (not shown).

  The rotation detecting device A is configured by the above-described units.

  The rotation detection device A includes an insertion portion 1a through which the axle shaft S is inserted, a housing 1 disposed between the hub 10a of the front wheel 10 and the front fork, and the housing 1 disposed in the housing 1 to generate the magnetic field. A magnet 3a and a magnetic detection element 3 that is disposed in the housing 1 in a state in which the change in the magnetic field can be detected and detects the change in the magnetic field accompanying the rotation of the detection target 5; Since the detection target 5 is formed of a metal material that is a magnetic material, the detection target 5 is formed of a magnetic material different from that of the hub 10a and rotates in synchronization with the hub 10a. Even if an attachment error of the device A to the hub 10a occurs, the detected object 5 can be prevented from being damaged.

  Moreover, in this embodiment, the to-be-detected body 5 is the base part 5b which has the hole part 5b1 which the insertion part 1a penetrates, and supports the to-be-detected part 5a, and the rotation transmission part which transmits rotation of the hub 10a to the base part 5b. The detected body 5 can be easily fixed to the hub 10a by being provided with a certain recess 5c and being fitted and fixed to the protrusion 10c provided on the hub 10a. In addition, since the attachment stability of the detection object 5 to the hub 10a is improved, a rotation detection device with good detection accuracy by the magnetic detection element 3 can be provided.

  Moreover, in this embodiment, by providing the recessed part 5c with a pair of raised parts 5d that sandwich and fix the protruding part 10c of the hub 10a, the detected object 5 can be attached to the hub 10a without rattling. Therefore, the attachment stability of the detection object 5 to the hub 10a is improved, and a rotation detection device with good detection accuracy by the magnetic detection element 3 can be provided.

  Further, in the present embodiment, the housing 1 includes the first storage portion 1b for bringing the detected portion 5a close to the magnetic detection element 3 and rotatably storing the detected portion 5a. It becomes possible to improve the detection accuracy by the detection element 3.

  In the present embodiment, the recess 5c is provided in the base portion 5b of the detected object 5, and a pair of raised portions 5d is provided in the recessed portion 5c, and the protruding portion 10c of the hub 10a is sandwiched between the pair of raised portions 5d to be detected. The body 5 is fitted and fixed to the hub 10a. For example, the base 5b, the recess 5c, and the raised portion 5d are eliminated, and the detected body 5 is configured only by the detected portion 5a made of a plate-like protruding piece. The lower end portion of the detected portion 5a may be press-fitted and fixed in a concave groove formed at the end of the tubular portion 10b of the hub 10a. Further, the detected portion 5a is not a plate-like protruding piece, and for example, it is possible to apply a magnetic body whose top is made of a substantially disk-like screw or pin shape (columnar rod-like member). You may press-fit a lower end part to the said groove part. By configuring the detected body 5 with only the detected section 5a in this way, the configuration of the detected body 5 becomes simple, and an inexpensive rotation detection device can be provided.

  Further, in the present embodiment, a pair of recesses 5c are provided in the base portion 5b of the detection object 5, and a pair of raised portions 5d are provided in each recess 5c, respectively, so that the cylindrical portion of the hub 10a corresponds to each recess 5c. The case where the two protrusions 10c formed at the end of 10b are sandwiched between the pair of raised portions 5d and the detected body 5 is fitted and fixed to the hub 10a has been described. The rotation transmission is provided with a concave-shaped arrangement portion and a pair of raised portions on each of the arrangement portions, and projecting toward the hub 10a side of the base portion 5b so as to correspond to the arrangement portions. It is also possible to sandwich the two convex portions, which are portions, between the pair of raised portions, and fit and fix the detected body 5 to the hub 10a. In this case, the pair of raised portions are eliminated, and the convex portions provided behind the base portion 5b are press-fitted and fixed to the concave arrangement portions provided at the end of the cylindrical portion 10b. Is also possible.

  In the present embodiment, the circuit board 2 is provided with the wiring pattern. However, for example, a three-dimensional conductive circuit is formed not on the circuit board 2 but on a housing 1 which is a resin molded body, and the housing 1 is replaced with 3 It may be formed as a three-dimensional injection molded circuit component. Such a configuration eliminates the need for a circuit board, thereby providing a more inexpensive rotation detection device.

It is principal part sectional drawing of the rotation detection apparatus by embodiment of this invention. It is BB sectional drawing of FIG. It is a perspective view of the to-be-detected body and hub by embodiment same as the above.

Explanation of symbols

A rotation detection device 1 housing 1a insertion portion 1b first storage portion (storage portion)
DESCRIPTION OF SYMBOLS 1c 2nd accommodating part 1d 3rd accommodating part 1e 4th accommodating part 2 Circuit board 3 Magnetic detection element (magnetic detection body)
4 Seal member 5 Detected object 5a Detected part 5b Base part (supporting part)
5b1 hole 5c recess (rotation transmission part)
5d ridge 10 front wheel (wheel)
10a Hub 10b Tubular part 10c Protruding part S Axle

Claims (6)

A housing having an insertion portion through which an axle on which a wheel of a motorcycle is mounted is inserted is disposed between the hub and the front fork of the wheel, a magnet that is disposed in the housing and generates a magnetic field, and a change in the magnetic field A rotation detection device including at least a magnetic detection body that is disposed in the housing in a state in which the detection of the magnetic field can be detected and detects a change in the magnetic field accompanying rotation of the detection target,
The detected body is formed of a magnetic material different from that of the hub, and includes at least a detected portion that rotates in synchronization with the hub .
The rotation detection apparatus according to claim 1, wherein the detected portion includes a plurality of plate-like projecting pieces positioned around the insertion portion so as to be separated from the insertion portion . The detected body includes a support portion that includes a hole portion through which the insertion portion is inserted and supports the detected portion, and a rotation transmission portion that transmits rotation of the hub to the support portion. The rotation detection device according to claim 1. The rotation detection device according to claim 2, wherein the support portion includes a recess that is the rotation transmission portion that fits into a protrusion provided on the hub. The rotation detecting device according to claim 3, comprising a pair of raised portions that are fixed to the concave portion with the protruding portion interposed therebetween. The rotation detection device according to claim 2, further comprising a convex portion that is the rotation transmission portion that fits into a concave-shaped arrangement portion provided on the hub. The rotation detection device according to claim 1, wherein the housing includes a storage portion that allows the detected portion to be close to the magnetic detection body and that rotatably stores the detected portion. .

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