JP3693157B2 - Rotation detector - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a rotation detection device which is attached to a hub of a front wheel of a two-wheeled vehicle such as a motorcycle or a bicycle and transmits the number of rotations of the wheel of the two-wheeled vehicle to an indicating instrument such as a speedometer.
[0002]
[Prior art]
A conventional rotation detection device is disclosed in Japanese Patent Laid-Open No. 2-264817. When such a rotation detection device is used as a rotation detection device for a two-wheeled vehicle (for example, a motorcycle), the rotation detection device is mounted on a circuit board in a substantially cylindrical resin case having a detection surface for detecting an object to be detected. A magnetic detection element (Hall IC) and a magnet are 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. In general, this rotation detection device is attached to a mission case or a sprocket cover, and the object to be detected detects the transmission gear rotating inside the sprocket, the tooth tip of the sprocket, or the like.
[0003]
When such a rotation detection device is used to detect the gear tip of a transmission gear or sprocket as a detected object, the detected object has some clearance, so the body rigidity of the vehicle (two-wheeled vehicle) Since the detected object vibrates due to the amount of exhaust or the exhaust amount, and the detection position gap between the detected 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 output from the rotation detection device, for example, there is a problem that it may cause a malfunction of the indicating instrument that displays the speed.
[0004]
Accordingly, the applicant of the present application pays attention to the above-mentioned problems, and has proposed an electric rotation detection device that is mounted on the hub of the front wheel of a two-wheeled vehicle, as disclosed in JP-A-9-229714. The rotation detection device includes a resin housing having an insertion portion through which a two-wheeled vehicle axle (front wheel axle) is inserted, and the insertion portion has a plurality of magnetic poles that rotate in synchronization with a wheel mounted on the axle. A body is mounted, and the rotation of the rotating body is detected by a magnetic detection unit including a Hall IC housed in the housing, without being affected by detection noise due to vibration of the detected body, Accurate rotation detection can be obtained.
[0005]
[Problems to be solved by the invention]
However, in recent years when the cost of a rotation detection device applied to a two-wheeled vehicle is required to be reduced, the magnetic detection unit tends to be changed from a magnetic detection element such as a Hall IC to an inexpensive magnetic reaction element such as a reed switch. It is in. However, the magnetic detection means using the magnetic reaction element has a problem that its vibration resistance performance is inferior to that of a magnetic detection unit using a Hall IC or the like due to its characteristics and structure.
[0006]
Therefore, the present invention pays attention to the above-described problems, and an object thereof is to provide a rotation detection device having excellent vibration resistance even when an inexpensive magnetic reaction element is used for a magnetic detection unit.
[0007]
[Means for Solving the Problems]
In order to solve the above problems, the present invention provides a housing having one end abutting against a bearing disposed on a hub of a wheel and a cylindrical insertion portion through which an axle passing through the bearing is inserted, and the insertion portion together but comprises a cylindrical portion to be inserted, and the rotator ing a magnetic material the rotation of the wheel by abutment to the rotation urging unit provided in the hub comprising a rotation transmitting unit for transmitting to said cylindrical portion, In a rotation detection device comprising a lubricant provided in the housing and a rotation detection unit disposed in the housing and detecting the rotation of the rotating body , the rotation transmission unit is opposed to the rotation urging unit. Protrusions are provided at locations .
[0008]
And a housing having one end abutting against a bearing disposed on a hub of the wheel, a cylindrical insertion portion through which an axle passing through the bearing is inserted, and a cylindrical portion through which the insertion portion is inserted. A rotating body made of a magnetic material provided with a rotation transmitting portion that transmits rotation of the wheel to the cylindrical portion by contacting a rotation urging portion provided in the hub, and a lubricant provided in the housing, In the rotation detection device that is disposed in the housing and includes a reed switch that detects the rotation of the rotating body, a protrusion is provided at a location facing the rotation urging portion of the rotation transmitting portion .
[0009]
The rotating body is formed of a plastic magnet .
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. 1 to 5, the rotation detection device A includes a housing 1, a circuit board 2, a magnetic detection unit (rotation detection unit) 3, a spacer 4, a rotating body 5, a seal member 6, and a wiring cord 7. It consists of and.
[0014]
The housing 1 is made of a resin material such as polybutylene terephthalate or nylon. A cylindrical insertion portion 1a made of a metal material into which an axle, which will be described later, is inserted is insert-molded at substantially the center of the housing 1, and a rotating body 5 described in detail later is provided outside the insertion portion 1a. A storage space 1b is formed to be rotatably arranged with respect to the outer periphery of the insertion portion 1a. Further, a wall portion 1c surrounding the rotating body 5 is formed at the periphery of a portion where the rotating body 5 described in detail after being mounted on the insertion portion 1a in the storage space 1b is provided, and this wall portion 1c. And a lubricant 8 made of grease or the like is applied between the rotating body 5 fitted in the insertion portion 1a. In addition, a rotation detection surface 1d that is close to the cylindrical portion of the rotating body 5 is provided at a predetermined location on the wall 1c.
[0015]
Further, the housing 1 is formed with a storage portion 1e having a guide groove (not shown) for receiving and supporting the circuit board 2 and a magnetic detection portion 3 which is a rotation detection portion, which will be described in detail later. By storing the circuit board 2 along the guide groove of the storage unit 1e, the magnetic detection unit 3 is disposed to face the magnetic detection surface 1d. A mounting portion 1f for press-fitting and holding a seal member 6 to be described in detail later is formed at the open end of the housing 1 (below the housing 1 in FIG. 2).
[0016]
The circuit board 2 is made of an insulating material such as paper phenol or glass epoxy, and a wiring pattern (not shown) is formed. A land portion (not shown) formed in a predetermined portion of the wiring pattern, a magnetic detection unit 3 and a wiring cord 7 Is electrically fixed by solder. The circuit board 2 is disposed in the storage portion 1e so that the magnetic detection portion 3 corresponds to the position of the rotation detection surface 1d formed on the housing 1, and then the sealing member made of epoxy or the like in the storage portion 1e. 9 is filled and fixedly arranged in the storage portion 1e.
[0017]
The magnetism detection unit 3 is composed of, for example, a reed switch and is composed of a magnetic reaction element that detects a change in magnetic pole.
[0018]
The spacer 4 has a hole 4a through which the insertion portion 1a of the housing 1 is inserted, and is a magnetic member made of a metal material such as SK, SUM, and SS. The spacer 4 is an annular plate-like member. In the present embodiment, the spacer 4 is insert-molded on the bottom surface 1g of the housing 1 and is disposed so as to surround the insertion portion 1a on the bottom surface 1g.
[0019]
The rotating body 5 is in contact with the cylindrical portion 5a that is fitted in the insertion portion 1a of the housing 1 and is rotatable with respect to the outer periphery of the insertion portion 1a, and the rotation urging portion 10a of the hub 10 of the front wheel 11 shown in FIG. The rotation transmission part 5b which transmits rotation of the wheel 11 to the cylindrical part 5a is provided, and this cylindrical part 5a and the rotation transmission part 5b consist of magnetic materials, for example, a plastic magnet of an anisotropic material or an isotropic material, for example Are integrally formed. That is, the insertion part 1a passes through the hole 5c provided in the cylindrical part 5a, and the rotating body 5 is provided to be rotatable with respect to the insertion part 1a. The cylindrical portion 5a of the rotating body 5 is subjected to, for example, quadrupole magnetization (800 to 600 gauss), and the magnetic detection unit 3 can detect a change in the magnetic pole accompanying the rotation of the cylindrical portion 5a.
[0020]
Moreover, the convex part 5d which can contact | abut the inner wheel 12a is provided in the location facing the inner wheel 12a in the bearing 12 of the rotary body 5. As shown in FIG. The four convex portions 5d are provided partially at the periphery of the hole portion 5c through which the insertion portion 1a is inserted at a location facing the inner wheel 12a.
[0021]
Further, when the rotating body 5 is fitted into the insertion portion 1a of the housing 1 with the cylindrical portion 5a, the arrangement position of the convex portion 5d is in a state in which a minute distance L is secured from the end portion of the insertion portion 1a. In the housing 1.
[0022]
Further, the rotating body 5 protrudes in contact with a rotation biasing portion 10a of the hub 10 of the rotation transmitting portion 5b (abutting on the rotation transmitting portion 5b and transmitting the rotation of the front wheel 11 to the rotation transmitting portion 5b). A portion 5e is provided. In this embodiment, the protruding portion 5e has a hemispherical shape, and makes point contact with the rotation urging portion 10a. In addition, the shape of this protrusion part 5e is not limited to this embodiment, The line | wire contact may be carried out with the said rotation urging | biasing part, and what is necessary is just a shape which keeps a contact area small.
[0023]
The seal member 6 is made of an elastic member such as nitrile or silicon, and has a thin cylindrical shape. The seal member 6 is formed with a groove portion 6a having a substantially V-shaped cross section over the entire circumference, and a metal material having a substantially L-shaped cross section is formed on the outer thick portion from the groove portion 6a. A holding member 6b made of insert molding is performed. The sealing member 6 is held by being press-fitted into the mounting portion 1 f of the housing 1 by being formed so that the outer diameter is slightly larger than the inner diameter of the peripheral wall of the mounting portion 1 f of the housing 1. The Rukoto.
[0024]
The wiring cord 7 transmits an output signal from the magnetic detection unit 3 to the outside through the circuit board 2, and a connector portion 7 a for connecting to other devices is provided at the end of the wiring cord 7. ing.
[0025]
The rotation detection device A is configured as described above. Next, the configuration of the two-wheeled vehicle to which the rotation detection device A is attached will be described.
[0026]
Reference numeral 10 denotes a hub of a front wheel (wheel) 11 of a motorcycle or the like, 10a denotes a locking claw which is a rotation urging portion for transmitting rotation to the front wheel 11 to the rotation transmitting portion 5b of the rotating body 5, and 12 denotes the hub 10. While being press-fitted and disposed in the provided recess 10b, the inner wheel 12a and the outer wheel 12b are provided, and the outer wheel 12b is a bearing that rotates with respect to the inner wheel 12a via a ball 12c. With the configuration of each part described above, the front wheel 11 is attached to the axle 13 by the inner wheel 12a of the bearing 12, and is disposed rotatably with respect to the axle 13 by the outer wheel 12b.
[0027]
Next, the attachment of the rotation detection device A to a two-wheeled vehicle will be described with reference to FIG. The rotation detection device A attached to the front wheel 11 having the above configuration allows the axle 13 to be inserted into the insertion portion 1 a of the housing 1, and the rotation transmitting portion 5 b provided in the rotating body 5 to be rotated by the rotation formed on the hub 10. It is mounted between the front fork 14 and the front wheel 11 by being brought into contact with the side surface 10c of the portion 10a and being fitted into the hub 10 so that the insertion portion 1a of the housing 1 is brought into contact with the inner wheel 12a of the bearing 12. As the front wheel 11 rotates, the rotating body 5 can rotate.
[0028]
In this rotation detection device A, a spacer 4 as a magnetic member is disposed on the bottom surface 1g of the housing 1, and the cylindrical portion 5a on which the rotator 5 is magnetized is provided by the presence of the spacer 4 made of a magnetic material. It will be held in close contact with the bottom 1g. Therefore, the magnetism detecting unit 3 rotates even when vibrations received from an idling engine or external factors are transmitted to the rotating body 5 (transmitted via the rotation transmitting unit 5b), particularly when the vehicle is stopped. Since the body 5 is held in close contact with the spacer 4, the vibration of the rotating body 5 is suppressed, and erroneous detection in magnetic detection can be prevented.
[0029]
This is important in preventing erroneous detection by the magnetic detection unit 5 because the vibration form transmitted to the rotating body 5 is different between the inner wheel 12a and the outer wheel 12b of the bearing 12.
[0030]
As shown in FIG. 4, the inner wheel 12 a of the bearing 12 is connected to the cylinder 11 a in the hub 10 of the housing 1 (insertion portion 1 a), the inner wheel 12 a, and the front wheel 11 from the right side of the drawing via the axle 13. The intermediate cylinder 15 is fixed with the front fork 14 sandwiched between the housing 1 and the inner wheel 12a provided with the magnetic detection unit 3, and the same vibration occurs even when the inner wheel 12a vibrates. On the other hand, the outer wheel 12b of the bearing 12 is fixed to the hub 10 of the front wheel 11, and the front wheel 11 and the outer wheel 12b have the same vibration even when they vibrate. Since the inner wheel 12a and the outer wheel 12b are interposed via the ball 12c, vibration is not transmitted uniformly. Therefore, the vibration mode of the rotation detection device A attached to the axle 13 via the insertion portion 1a and the outer wheel 12b of the bearing 12 are different from the vibration mode transmitted from the tire attached to the front wheel 11. Thus, when the rotating body 5 is brought into contact with the outer wheel 12b having a vibration mode different from that of the magnetic detection unit 3 serving as the rotation detection unit, the vibration mode may be different and erroneous detection may occur. Therefore, when the rotating body 5 is brought into contact with the inner wheel 12a having the same vibration form as that of the magnetic detection part 3 serving as the rotation detection part, the vibration form becomes the same and erroneous detection can be prevented.
[0031]
In addition, even if the rotating body 5 is not in close contact with the bottom surface 1g of the housing 1 due to excessive vibration and the rotating body 5 moves in the bearing 12 direction, the rotating body 5 is rotated by the convex portion 5d formed on the rotating body 5. The body 5 abuts against the inner wheel 12a of the bearing 12 and can maintain a state where it does not abut against the outer wheel 12b. This is important in preventing erroneous detection by the magnetic detection unit 5 because the vibration form transmitted to the rotating body 5 is different between the inner wheel 12a and the outer wheel 12b of the bearing 12.
[0032]
Further, by providing a protrusion at the portion where the rotation transmitting portion 5b of the rotating body 5 is in contact with the rotation urging portion 10a, the contact area between the rotation transmitting portion 5b and the rotation urging portion 10a can be reduced. Even when the vibration received from the idling engine or external factors is transmitted to the rotating body 5 (transmitted via the rotation transmitting portion 5b) when the vehicle is stopped, the rotating body 5 is in close contact with the spacer 4. Even when the rotation transmitting portion 5b of the rotating body 5 is in contact with the rotation biasing portion 10a, the contact area between the two members can be kept small by the presence of the protruding portion 5e. Therefore, it is possible to prevent erroneous detection in magnetic detection.
[0033]
This is because the lubricant 8 provided in the housing 1 scatters in the space sealed by the housing 1 and the seal member 6 when the vehicle is used, and the rotating body 5 rotates, and the rotation transmitting portion 5b and the rotation are attached. The lubricant 8 also enters the portion that comes into contact with the urging portion 10a. In this case, when the contact portion between the rotation transmitting portion 5b and the rotation urging portion 10a is in surface contact, the lubricant 8 is in a state in which the rotation transmitting portion 5b and the rotation urging portion 10a are attached, and vibration is generated. For example, the rotation urging unit 10a does not easily move away from the rotation transmitting unit 5b, and as a result, the rotating body 5 is moved and appears as detection noise of the rotation detecting device A.
[0034]
On the other hand, by adopting the present embodiment, even if the lubricant 8 enters the portion where the rotation transmitting portion 5b and the rotation urging portion 10a come into contact, the rotation transmitting portion 5b and the rotation urging portion 10a. since abutting portion is in point contact with, not the state where the lubricant 8 had paste and the rotation transmitting portion 5b and the rotation urging portion 10a, due to vibration, rotation urging unit 10a is the rotation transmission Generation of detection noise of the rotation detection device A can be suppressed without easily moving away from the part 5b and moving the rotating body 5.
[0035]
In the present embodiment, the shape of the protruding portion 5e is a hemispherical shape, but is not limited to this shape, and the contact area of the contact portion between the rotation transmitting portion 5b and the rotation biasing portion 10a is reduced. Any shape can be used as long as the shape is suitable. For example, a shape like a wall may be used so as to make line contact. Further, the cross section is not limited to a spherical shape, and the cross section may have a shape having an angle where two straight lines intersect.
[0036]
Further, when the rotation urging portion 10a of the hub 10 is provided with a protruding portion, the contact portion of the rotation transmitting portion 5b may be a flat surface.
[0037]
Moreover, by providing the protrusion 5e on the rotating body 5 made of a plastic magnet, the protrusion 5e can be easily formed at low cost, and the cost can be reduced.
[0038]
The shape of the rotation urging unit 10a is also not limited to the rotation urging unit 10a of the present embodiment, the cutout portion is formed, it may be one which is adapted to position the rotation transmitting portion 5b here .
[0039]
The erroneous detection in the magnetic detection is conspicuous when the magnetic detection unit 3 is constituted by a reed switch and the magnetized region applied to the cylindrical portion 5a is located at the switching point on the magnetic detection surface 1d of the housing 1. Rotation detection device that can detect good rotation even when an inexpensive magnetic detection unit using the reed switch is used because the rotation of the rotating body 5 by the hub 10 can be suppressed. A can be configured.
[0040]
In the embodiment of the present invention, the spacer 4 is disposed on the bottom surface 1g of the housing 1 by insert molding. However, in the present invention, the spacer 4 is disposed and fixed on the bottom surface 1g of the housing 1 with an adhesive or the like. It may be what you do.
[0041]
Next, another embodiment of the present invention will be described with reference to FIG. 6, but the same reference numerals are given to the same or corresponding portions as those of the above-described embodiment, and detailed description thereof will be omitted.
[0042]
6 is different from the above-described embodiment in that the rotating body 5 is held in close contact with the bottom surface 1g of the housing 1 without providing the spacer 4 made of a magnetic member. It is in.
[0043]
That is, the rotation detection device A is configured such that the insertion portion 1a provided in the housing 1 is made of the same material (metal material as SK, SUM, SS, etc.), for example, with the spacer 4 of the above-described embodiment. By providing a contact portion (magnetic member) 1h that contacts the cylindrical portion 5a of the rotating body 5 at the bottom 1g portion of the housing 1, the cylindrical portion 5a of the rotating body 5 is placed on the bottom surface of the housing 1 in the same manner as in the above-described embodiment. It is held in close contact with the 1g side.
[0044]
Such a rotation detection device A is provided integrally with the insertion portion 1a, and an effect equivalent to that in the case where the spacer 4 is provided is obtained by the contact portion 1h exposed from the bottom surface 1g of the housing 1. Further, by forming the contact portion 1h, which is a magnetic member, integrally with the insertion portion 1a, the number of parts is reduced, and the manufacturing cost of the rotation detection device A can be reduced.
[0045]
In the embodiment, the rotating body 5 is pulled toward the bottom 1 side of the housing 1 and rarely comes into contact with the inner wheel 12a. However, the spacer 4 of the embodiment is a corrugated washer, and the rotating body 5 is rotated. The present invention may be applied to a structure in which the body 5 is pressed toward the bearing 12. Also in this case, since the rotating body 5 abuts on the inner wheel 12a by the convex portion 5d and the vibration of the rotating body 5 can be suppressed, it is good even when an inexpensive magnetic detection unit using the reed switch is used. It is possible to configure the rotation detection device A that enables accurate rotation detection.
[0046]
Further, in the embodiment of the present invention, the description has been made using the rotating body 5 that is integrally provided with the cylindrical portion 5a and the rotation transmitting portion 5b using a plus chip magnet. However, the rotating body in the present invention has a plurality of magnetic poles. The cylinder part 5a and the rotation transmission part 5b which transmits rotation of a wheel to this cylinder part 5a may be provided separately.
[0047]
In each of the embodiments of the present invention, as the rotating body 5, a cylindrical portion 5a having a plurality of magnetic poles and a rotation transmitting portion 5b for transmitting the rotation of the front wheel 10 to the cylindrical portion 5a are integrally provided by a plastic magnet. In the present invention, an uneven portion (gear structure) is provided on the outer periphery (outer surface) of the cylindrical portion of the rotating body attached to the insertion portion, and the rotation transmitting portion is provided on the uneven portion. Based on Japanese Patent Application No. 11-54850 filed earlier by the applicant of the present application for transmitting the rotation of the front wheel via a magnetic detecting unit mainly composed of a magnet and a Hall IC. This is also effective in the structure of the rotation detection device.
[0048]
【The invention's effect】
The present invention can achieve the initial purpose, and can provide a rotation detection device having excellent vibration resistance even when an inexpensive magnetic reaction element such as a reed switch is used as a magnetic detection unit. .
[Brief description of the drawings]
FIG. 1 is an exploded perspective view showing a rotation detection device according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view of a main part of the rotation detection device according to the embodiment.
FIG. 3 is a plan view of the housing according to the embodiment.
FIG. 4 is a view showing an attachment state of the rotation detection device according to the embodiment;
FIG. 5 is a view showing a relationship between a rotating body and a hub according to the embodiment.
FIG. 6 is a cross-sectional view of a main part showing a rotation detection device according to another embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Housing 1a Insertion part 3 Magnetic detection part (Rotation detection part)
DESCRIPTION OF SYMBOLS 5 Rotating body 5a Cylindrical part 5b Rotation transmission part 5e Protrusion part 10 Hub 10a Rotation biasing part (locking claw)
11 Front wheel (wheel)
12 Bearing 13 Axle A Rotation detector

Claims (3)

One end abuts on a bearing disposed on the hub of the wheel, a housing including a cylindrical insertion portion through which an axle passing through the bearing is inserted, a cylindrical portion through which the insertion portion is inserted, and a rotating body ing a magnetic material with a rotation transmitting portion for transmitting the rotation of the wheel to the cylindrical portion by abutting the rotation urging unit provided in the hub, and a lubricant provided in said housing, said A rotation detection device that is disposed in a housing and detects a rotation of the rotating body , wherein a protrusion is provided at a position opposite to the rotation urging portion of the rotation transmitting portion. Rotation detection device. One end abuts on a bearing disposed on the hub of the wheel, a housing including a cylindrical insertion portion through which an axle passing through the bearing is inserted, a cylindrical portion through which the insertion portion is inserted, and A rotating body made of a magnetic material provided with a rotation transmitting portion that transmits rotation of the wheel to the cylindrical portion by contacting a rotation urging portion provided in the hub, a lubricant provided in the housing, and the housing And a reed switch that detects rotation of the rotating body, wherein a rotation portion is provided with a protruding portion at a position facing the rotation urging portion of the rotation transmitting portion. Detection device. The rotation detecting device according to claim 1, wherein the rotating body is formed of a plastic magnet.

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