JPH04134072U - rotation speed sensor - Google Patents

Abstract

(57) [Summary] [Purpose] The purpose of the present invention is to extend the lifespan and reduce the cost of a rotation speed sensor mainly used for detecting the vehicle speed of an automobile. [Structure] A washer 3 is fixed on the axial sliding surface of the bearing 4 attached to the lower case 6 of the magnet attached to the shaft 1a.
By fixing the shaft, the flange that was conventionally provided by cutting the shaft is eliminated, reducing the number of machining steps and increasing the lifespan by appropriately selecting the fixing washer.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention is mainly related to a rotation speed sensor used for detecting vehicle speed. .

0002

[Conventional technology]

A conventional rotation speed sensor will be explained with reference to FIG. According to the same figure, the rotation speed sensor is located at the bottom. It has a collar with a diameter larger than the diameter of the fitting part with the bearing 4 which is formed integrally with the case 6. A shaft 1, a multipolar magnet 2 fixed to the shaft 1 by adhesive or the like, and a magnetoelectric transducer 5. The rotating body consists of a shaft 1 and a multipolar magnet 2, and a bearing 4 slides in the axial direction. The surface was formed by the collar of the shaft 1 and the end surface of the bearing 4.

0003 Note that 8 is a spring attached to this shaft 1, and the thrust stud 9 is attached to the upper case 7 side. By pushing the provided thrust receiving plate 10, the shaft 1 slides on the bearing 4. become. Further, 11 is a terminal for leading the output of the magnetoelectric converter 5 to the outside.

0004

[Problem that the idea aims to solve]

However, in the conventional rotation speed sensor mentioned above, in order to ensure the rotation life, The area of the sliding surface is secured in order to suppress the contact pressure per unit area applied to the sliding surface. Shaft 1 is made by cutting from a large diameter shaft material, which is expensive. It was becoming.

[0005] This invention solves these conventional problems and uses an inexpensive rotation speed sensor. This is what we provide.

[0006]

[Means to solve the problem]

In order to solve the above problem, this invention has a fixed washer fixed to the shaft. It is something.

[0007]

[Effect]

Therefore, according to the present invention, the axial sliding surface is formed by the fixed washer and the bearing. The area and material of the axial sliding surface should be adjusted to ensure a long rotation life. , can be secured by easy assembly method regardless of shaft processing and external shape. This makes it possible to provide an inexpensive rotation speed sensor.

[0008]

【Example】

An embodiment of the rotation speed sensor of the present invention will be explained with reference to FIGS. 1 and 2. In addition, conventional technology Parts that are the same as the technique are given the same numbers and explanations are omitted. In Figures 1 and 2, 1a is 2a is a multi-pole magnetized plastic integrally molded on the outer periphery of the shaft 1a. It is a magnetic magnet and has a protrusion 2b on its lower surface. 3 is a fixed washer, Recesses 3a and 3b are provided around the periphery, and the recesses 3a and 3b are fitted into the protrusion 2b. did. This fixed washer 3 is attached to the magnet 2a.

[0009] Next, to explain the operation, the shaft 1a and the magnet 2a are fixed by a spring 8. It is pressed against the bearing 4 via the shear 3. and rotating the axis 1a As a result, the magnet 2a rotates and an alternating magnetic field is generated at a fixed point on the outer periphery of the magnet 2a. child The alternating magnetic field is extracted as an electric signal by the magnetoelectric converter 5 and the rotation speed is detected.

0010 Here, as shown in FIG. The fixing washer 3 is fitted onto the protrusion 2b of the shaft 1a. and is substantially fixed to the magnet 2a in the rotational direction. Therefore, the fixed washer 2a and the shaft 1a and the magnet 2a rotate together, and the axial sliding surface is connected to the fixed washer 3 and the bearing 4. It will be composed of:

[0011]

[Effect of the idea]

As is clear from the above embodiment, the present invention uses a fixed washer and a bearing in the axial direction. The area and material of the sliding surface in the axial direction are determined to ensure the rotational life of the sliding surface. , it is possible to secure it by an easy assembly method, regardless of the processing and external shape of the shaft. This has the effect of providing an inexpensive rotation speed sensor. .

[Brief explanation of drawings]

[Fig. 1] Side sectional view of one embodiment of the rotation speed sensor of the present invention

[Fig. 2] An exploded perspective view explaining the relationship between the main parts, the shaft and the fixed washer.

[Figure 3] Side sectional view of a conventional rotation speed sensor

[Explanation of symbols]

1a axis 2a magnet 3 Fixed washer 4 Bearing 5 Magnetoelectric converter 8 Spring

Claims (1)

[Scope of utility model registration request] 1. A shaft, a bearing, a multipolar magnetized magnet integrally molded on the shaft, a fixed washer substantially fixed to the magnet or the shaft in the rotational direction of the shaft, and the magnet A rotation speed sensor comprising: a spring that presses the magnet against the bearing; and a magnetoelectric transducer disposed opposite to the magnetized surface of the magnet.