JPH08183303A - Bearing device for axle - Google Patents

Abstract

PURPOSE: To compute wheel speed accurately without being influenced by an outer peripheral shape of a nut. CONSTITUTION: Pulse dentition 21 is formed on an end surface of a nut 20, a pitch of an output signal generated between an electromagnetic sensor 13 and the pulse dentition 21 is read by the electromagnetic sensor 13 facing against the pulse dentition 21, and the number of rotation of an axle shaft 6 is detected. An output waveform of the electromagnetic sensor 13 is not influenced upon by an outer peripheral shape of the nut 20, and a pitch error of the output waveform is reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an axle bearing device incorporating an antilock brake sensor mainly used in automobiles.

[0002]

2. Description of the Related Art An example of a conventional bearing device for an axle of this type is shown in FIGS. As shown, the bearing 1 includes an outer ring 2 and an inner ring 4 that is rotatably provided inside the outer ring 2 via a plurality of rolling elements 3. Each rolling element 3 is held by a cage 5.

An axle shaft 6 is press-fitted into the inner diameter surface of the inner ring 4. A flange 7 that is bolted to the vehicle body is provided on the outer circumference of the outer ring 2, and a flange 8 to which the wheel is attached is provided at one end of the axle shaft 6. A nut 9 having a hexagonal outer circumference is screwed into the other end of the axle shaft 6, and the inner ring 4 is tightened by the nut 9 and the flange 8 to move the axle shaft 6 in the axial direction with respect to the bearing 1. And the inner shaft 4 and the axle shaft 6 are rotated integrally. The nut 9 is made of steel, which is a magnetic material.

A pulse ring 10 that rotates together with the inner ring 4 is provided on the outer side of the nut 9. A pulse tooth row 11 is radially formed on one side surface of the pulse ring 10. A case 12 is fitted on one side of the outer ring 2, and the case 12 is provided with an electromagnetic sensor 13. The tip of the electromagnetic sensor 13 faces the pulse tooth row 11, and the rotational speed of the axle shaft 6 is detected by reading the pitch of the output signal generated between the electromagnetic sensor 13 and the pulse tooth row 11. Based on this data, the rotation speed of the wheels and the acceleration of the vehicle body are calculated to control the brake.

[0005]

However, in the bearing device for an axle as described above, since the outer circumference of the nut 9 is hexagonal, as the nut 9 rotates, the distance between the outer circumference of the nut 9 and the electromagnetic sensor 13 is increased. Changes, and as shown in FIG. 5, undulations occur in the output waveform of the electromagnetic sensor 13. As a result, an error may occur when the pitch of the output signal is read, and an accurate rotation speed of the wheel may not be calculated.

Therefore, an object of the present invention is to provide a bearing device for an axle, which can calculate an accurate rotation speed of a wheel without being affected by the outer peripheral shape of the nut.

[0007]

In order to solve the above-mentioned problems, the present invention rotatably supports an axle shaft with a bearing provided with a rolling element between an outer ring and an inner ring, and the inner ring and the axle shaft are In a bearing device for an axle, which is tightened with a nut screwed into the end of the axle shaft, a pulse tooth row is formed on the end surface of the nut, and the rotational speed of the axle shaft is detected by an electromagnetic sensor facing the pulse tooth row. The structure was adopted.

[0008]

In the bearing device for an axle according to the present invention, since the electromagnetic sensor faces the pulse tooth row formed on the end surface of the nut, the outer peripheral shape of the nut does not affect the output waveform of the electromagnetic sensor. .

[0009]

Embodiments of the present invention will be described below with reference to the accompanying drawings. The same parts as those of the conventional example shown in FIG. 3 described above are designated by the same reference numerals and description thereof will be omitted.

As shown in FIG. 1, in the axle bearing device according to the present invention, the pulse ring 10 is omitted and the nut 9 is used.
Instead, the inner ring 4 is tightened with the nut 20. Pulse tooth rows 21 are radially formed on one side surface of the nut 20, and the pulse tooth rows 21 face the electromagnetic sensor 13.

In the above-described bearing device for an axle, the output waveform of the electromagnetic sensor 13 is not affected by the outer peripheral shape of the nut 20, and the undulation of the output waveform is suppressed as shown in FIG. , Pitch error is reduced,
The number of rotations of the axle shaft 6 per unit time can be accurately detected.

Further, since the pulse ring 10 is not required, the number of parts can be reduced, the assembly is facilitated, and the cost can be reduced.

Further, since the conventional one shown in FIG. 3 is used, no design change or size change is required.

[0014]

As described above, according to the present invention, since the electromagnetic sensor faces the pulse tooth row formed on the end surface of the nut, the outer peripheral shape of the nut does not affect the output waveform of the electromagnetic sensor. The pitch error of the output waveform is reduced, and the rotation speed of the axle shaft can be accurately detected.

Therefore, the rotational speed of the wheel can be calculated accurately, the malfunction of the antilock brake system is prevented, and the safety is improved.

[Brief description of drawings]

FIG. 1 (a) is a vertical sectional front view of an embodiment, and FIG. 1 (b) is a view showing an end surface of the nut.

FIG. 2 is a diagram showing an output waveform of an electromagnetic sensor of the embodiment.

FIG. 3 is a vertical sectional front view of a conventional example.

FIG. 4 is a vertical sectional side view of a main part of the same.

FIG. 5 is a diagram showing an output waveform of the electromagnetic sensor of the above.

[Explanation of symbols]

 1 Bearing 2 Outer ring 3 Rolling element 4 Inner ring 6 Axle shaft 9, 20 Nut 10 Pulse ring 11, 21 Pulse tooth row 13 Electromagnetic sensor

Claims (1)

[Claims] 1. An axle in which an axle shaft is rotatably supported by a bearing having a rolling element provided between an outer ring and an inner ring, and the inner ring and the axle shaft are fastened with a nut screwed into an end of the axle shaft. In the bearing device, a pulse tooth row is formed on the end surface of the nut, and the rotation speed of the axle shaft is detected by an electromagnetic sensor facing the pulse tooth row.