JPH0926429A - Rotation sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a low-cost rotation sensor improved in durability and simple in assembling operation while reducing the number of rotary components. SOLUTION: A sensor magnet 4 is mounted integrally with the end face of a sleeve 2 on which an input gear 3 is formed, the sleeve 2 is rotatably supported to a shaft member 5, which is fixed to a connector member 16. The magnet 4 is opposed to a magnet sensor 21 fixed to the end face of the member 16. As the bear 3 is rotated, the magnet 4 is rotated, and it is detected by the sensor 21.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotation sensor mounted on a transmission of an automobile and converting the rotation of the transmission into an electric signal to detect the vehicle speed.

[0002]

2. Description of the Related Art As a sensor for detecting a vehicle speed for an automobile, a rotation sensor for transmitting the rotation of an automobile transmission to a sensor magnet and detecting the rotation of the sensor magnet by a magnetic sensor and outputting it as an electric signal is known. Are known.

FIG. 3 shows a conventional example of this type of rotation sensor 100. An input gear 102 that meshes with a transmission of an automobile is fixed to a rear end side of an input shaft 101 that is rotatably inserted in a sleeve 110, and a groove 10 on a front end side
The small-diameter portion 105 of the magnet shaft 104 is fitted into the shaft 3 by the key 106. Large diameter part 1 of magnet shaft 104
The sensor magnet 4 is fixed to the tip of 07.
The large diameter portion 107 of the magnet shaft 104 is supported by a bearing 108, and the braking magnet 10 is attached to the tip of the bearing 108.
9 is attached. A washer 114 prevents the braking magnet 109 and the bearing 108 from coming off.

A flange 113 of a connector member 112 is fixed to a flange 111 at the tip of the sleeve 110. The sensor magnet 4 is provided on the rear surface of the connector member 112.
The magnetic sensor 21 that faces is fixed. A terminal 114 is connected to the magnetic sensor 21. A circumferential groove 115 is provided on the outer circumference of the input shaft 101, and the sleeve 1
Two linear grooves 116 facing the circumferential groove 115 are formed on the inner circumference of 00, respectively. By inserting a stop pin 117 into the circumferential groove 115 and the linear groove 116,
The input shaft 101 is prevented from coming off.

A technique similar to that of the conventional rotation sensor is also disclosed in Japanese Patent Laid-Open No. 3-249562.

[0006]

In the conventional rotation sensor 100 as described above, the input shaft 101 is used as a rotary wear component.
And sleeve 110, and magnet shaft 104 and bearing 1.
Since 08 is used, the number of rotating wear parts increases,
There is a problem in durability and cost. In order to improve the durability performance, it is necessary to use highly accurate parts, and there is a problem that the cost further increases.

Further, the input shaft 101 and the magnet shaft 104
Is molded separately, the sensor magnet 21 is attached to the magnet shaft 104, and the magnet shaft 104 is connected to the input shaft 101.
Since the key 106 is used for attachment, there is a problem that the assembling work is complicated.

The present invention has been made in view of the above points, and an object of the present invention is to provide a rotation sensor in which the number of rotating parts is reduced, the durability is improved and the cost is reduced, and the assembling work is easy. And

[0009]

In order to achieve the above object, the invention according to claim 1 is a rotation sensor for detecting rotation of a sensor magnet by a magnetic sensor, wherein the sensor magnet is provided with an input gear. The sleeve is integrally attached to the end surface of the sleeve, the sleeve is rotatably supported on the outer periphery of the shaft member fixed to the connector member, and the sensor magnet is opposed to the magnetic sensor fixed to the end surface of the connector member. It is a feature.

The invention according to claim 2 is the rotation sensor according to claim 1, wherein the shaft member is externally fixed to a shaft portion that rotatably supports the sleeve and the connector member. And a sleeve portion.

[0011] Further, the invention according to claim 3 is based on claim 1.
Alternatively, the rotation sensor according to the second aspect is characterized in that an O-ring is interposed between the outer circumference of the connector member and the inner circumference of the sleeve portion.

Further, the invention of claim 4 is the same as claim 1.
The rotation sensor according to any one of claims 1 to 3, wherein a coil spring is interposed between the rear end surface of the shaft portion and the ball inserted in the bottom surface of the sleeve.

Further, the invention of claim 5 is the same as claim 1.
5. The rotation sensor according to any one of claims 1 to 4, wherein a circumferential groove is formed on the outer circumference of the shaft portion, and two linear grooves facing the circumferential groove are formed on the inner circumference of the sleeve. A through hole communicating with the straight groove is formed in the sleeve, and a retaining member is inserted into the circumferential groove and the straight groove through the through hole.

Since the invention according to claims 1 to 5 has the above-mentioned structure, it has the following operation.

That is, in the invention described in claim 1, the rotation of the transmission is transmitted to the input gear of the sleeve,
The sleeve to which the sensor magnet is attached rotates about the shaft member, and the magnetic sensor detects the fluctuation of the magnetic field of the sensor magnet. The sensor magnet is integrally attached to the sleeve by insert molding or press fitting, so the sensor magnet can be easily attached, and the rotating friction part is only the sleeve and the shaft member, which reduces rotating wear parts and is durable. The property is improved.

According to the second aspect of the invention, the shaft member can be easily attached only by crimping the sleeve portion to the connector member.

Further, according to the invention of claim 3, the O-ring interposed between the outer circumference of the connector member and the inner circumference of the sleeve portion prevents foreign matter such as water from entering from the outside to prevent the internal equipment from being damaged. Can be protected.

Further, in the invention of claim 4, the vibration transmitted to the input gear is absorbed by the buffering action of the coil spring, and the rattling of the rotation sensor is alleviated.

Further, in the invention according to claim 5, the sleeve is rotatably locked to the shaft member by the retaining member, and the fall of the sleeve member is prevented, so that the shaft center is accurately aligned with the shaft member. be able to.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described based on embodiments shown in the drawings. The same members as those in FIG. 3 are designated by the same reference numerals.

1 and 2, the rotation sensor 1 is provided with a bottomed cylindrical sleeve 2 made of synthetic resin, an input gear 3 is integrally formed at the rear end side of the sleeve 2, and a flange 2a is provided at the front end. Are integrally formed. The sensor magnet 4 is embedded in the front surface of the flange 2a. The sensor magnet 4 is embedded in the sleeve 2 by being integrally molded by insert molding or fixed by press fitting when the sleeve 2 is molded.

A hole 6 is formed on the inner surface of the rear end of the sleeve 2, and a ball 7 is inserted into the hole 6. Washers 8 and 9 are interposed on both sides of the ball 7.

The shaft member 5 made of a non-magnetic material comprises a shaft portion 5a and a sleeve portion 5b, and the sleeve 2 is rotatably fitted to the outer periphery of the shaft portion 5a. On the rear end surface of the shaft portion 5a,
A hole 10 is formed so as to face the hole 6 of the sleeve 2, and a coil spring 11 for braking is inserted into the hole 10 to press a ball 7 via a washer 8 to prevent rattling of the sleeve and braking. A circumferential groove 12 is formed on the outer circumference of the shaft portion 5a, and linear grooves 13, 13 are formed on the inner circumferential surface of the sleeve 2 so as to face both sides of the circumferential groove 12. The upper and lower sides of the linear grooves 13 and 13 are through holes 1 formed in the sleeve 2.
4 (see FIG. 2).

By inserting the retaining pins 15 and 15 as retaining members into the through hole 14 of the sleeve 2, the retaining pins 15 and 15 engage with both the circumferential groove 12 and the linear grooves 13 and 13. As a result, the stop pin 15 is adapted to rotate along with the sleeve 2 along the circumferential groove 12. Further, the coil spring 11 exerts a force on the sleeve 2 in the direction of coming off the shaft portion 5a.
It is locked by 2 and is prevented from coming off. Furthermore, the sleeve 2
Is the shaft portion 5a due to the insertion of the locking pins 15 and 15 described above.
It is possible to prevent the falling of the shaft portion 5a against the shaft portion 5a and accurately align the shaft center with the shaft portion 5a. A spring pin is used as the stop pin 15.

The sleeve portion 5b of the shaft member 5 is fitted to the outer periphery of the connector member 16 and is fixed to the connector member 16 by caulking the tip 5c into the groove 17 formed in the outer periphery of the connector member 16. ing. An O-ring 19 is interposed between the connector member 16 and the sleeve portion 5b to prevent foreign matter such as water from entering from the outside, and thus the magnetic sensor 2
The protection of the magnetic sensor 21 is ensured, and thus the accurate operation of the magnetic sensor 21 can be ensured. An O-ring 20 is also attached to the front of the sleeve portion 5b. This O-ring 20
Has a function of maintaining airtightness with a fixing member (not shown) to which the rotation sensor 1 is attached.

A magnetic sensor 21 such as a hall element or a semiconductor is attached to the rear end of the connector member 16 so as to face the sensor magnet 4. This magnetic sensor 2
1 is a terminal 22 embedded in the connector member 16
The terminal 22 is pulled out to the connector portion 16a of the connector member 16 and connected to an indicating instrument (not shown).

An attachment portion 23 is integrally formed on one side of the connector member 16, and the metal spacer 2 is attached to the attachment portion 23.
4 is embedded.

The rotation sensor 1 of the present invention has the above-mentioned structure and operates as follows.

By engaging the input gear 3 with the transmission, the sleeve 2 fitted on the shaft portion 5a of the shaft member 5 rotates in synchronism with the transmission, and a change in the magnetic field due to the rotation of the sensor magnet 4 is detected by the magnetic sensor 21.
Then, an electric signal is transmitted from the terminal 22 to the indicating instrument. As the sleeve 2 rotates, the stop pin 15 rotates along with the sleeve 2 along the circumferential groove 12. Sleeve 2
Since the vibration of the engine is transmitted, the coil spring 11 and the ball 7 absorb the vibration and prevent the sleeve 2 from rattling.

As described above, the rotation sensor 1 of this embodiment
Since the sensor magnet 4 is integrally attached to the sleeve 2 of the input gear 3 by insert molding or press-fitting, the sensor magnet 4 is easier to attach than a structure in which the sensor magnet 4 is fixed to a separate magnet shaft. In addition, since the rotational friction portion is only the sleeve 2 and the shaft member 5, the number of rotating parts can be reduced, so that the durability is improved and the number of parts can be reduced, so that the cost can be reduced.

[0031]

As described above in detail, the present invention has the following effects.

That is, according to the invention of claim 1,
Since the sensor magnet is integrally attached to the sleeve where the input gear is formed by insert molding or press fitting, the sensor magnet can be easily attached, and the rotating friction part is only the sleeve and the shaft member. Since the number of parts can be reduced, the durability can be improved, the number of parts can be reduced, and low cost can be realized.

Further, according to the invention of claim 2, since the sleeve portion of the shaft member is swaged to the connector member, in addition to the effect of the invention of claim 1, the sleeve portion can be easily attached to the connector member. Can be attached to.

Further, according to the invention of claim 3, since the O-ring is interposed between the outer circumference of the connector member and the inner circumference of the sleeve portion, in addition to the effect of the invention of claim 1 or 2, It is possible to prevent the entry of foreign matter such as water to protect the magnetic sensor and to ensure its accurate operation.

Further, according to the invention described in claim 4, since the coil spring is interposed between the rear end surface of the shaft portion and the ball inserted in the bottom surface of the sleeve, any one of claims 1 to 3 is provided. In addition to the effects of the invention described in the paragraph, the vibration transmitted to the input gear is absorbed by the buffering action of the coil spring, and the rattling of the rotation sensor is reduced.

Further, according to the invention described in claim 5, since the retaining pin is inserted into the circumferential groove of the shaft portion and the linear groove of the sleeve, the sleeve is rotatably locked to the shaft member. In addition to the effect of the invention described in any one of claims 1 to 4, the sleeve can be easily attached to the shaft member only by the retaining member, and the removal of the sleeve can be surely stopped, and the sleeve can be attached to the shaft member. It is possible to prevent the shaft member from falling and to accurately match the shaft centers of the shaft member and the sleeve.

[Brief description of drawings]

FIG. 1 shows an embodiment of a rotation sensor of the present invention, FIG.
It is a vertical side view taken along line AA of FIG.

FIG. 2 is a partially cutaway perspective view of the rotation sensor of FIG.

FIG. 3 is a vertical sectional side view showing an example of a conventional rotation sensor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rotation sensor 2 Sleeve 3 Input gear 4 Sensor magnet 5 Shaft member 5a Shaft part 5b Sleeve part 7 Ball 11 Coil spring 12 Circumferential groove 13 Straight groove 14 Through hole 15 Locking pin (retaining member) 16 Connector member 19 O-ring 21 Magnetic sensor

Claims (5)

[Claims] 1. A rotation sensor for detecting rotation of a sensor magnet by a magnetic sensor, wherein the sensor magnet is integrally attached to an end surface of a sleeve in which an input gear is formed, and the sleeve is fixed to a connector member. Rotatably supported on the outer periphery of
A rotation sensor, wherein the sensor magnet is opposed to a magnetic sensor fixed to an end surface of the connector member. 2. The rotating member according to claim 1, wherein the shaft member is composed of a shaft portion that rotatably supports the sleeve, and a sleeve portion that is externally fixed to the connector member. Sensor. 3. The rotation sensor according to claim 1, wherein an O-ring is interposed between the outer circumference of the connector member and the inner circumference of the sleeve portion. 4. The rotation sensor according to claim 1, wherein a coil spring is interposed between a rear end surface of the shaft portion and a ball inserted in the bottom surface of the sleeve. . 5. A circumferential groove is formed on the outer circumference of the shaft portion, and a straight groove facing the circumferential groove is formed on the inner circumference of the sleeve,
5. A through hole communicating with the linear groove is bored in the sleeve, and a retaining member is inserted into the circumferential groove and the linear groove via the through hole. The rotation sensor according to item 1.