JPH11344502A - Bearing seal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dramatically improve sensitivity and durability by completely protecting a rotation speed detecting unit for detecting rotation speed, with respect to a sealing structure of a bearing which relatively rotates. SOLUTION: A magnetic circle 5a formed of combination of an elastic body and a ferromagnetic material is arranged on the outside of a reinforcing circle 5b, and a sealing portion 5d which covers the magnetic circle 5a and a sealing lip 5c which is continued from the sealing portion 5d and disposed on the periphery of the reinforcing circle 5b are integrally formed, thereby constituting a magnetic ring 5. Consequently, the magnetic circle 5a is completely isolated from outside air so that a correct and stable magnetic field is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seal structure of a bearing portion which rotates relatively, and more specifically, to a bearing having a rotation detecting device for detecting rotation speeds of front and rear wheels in an anti-lock brake system of an automobile. It relates to a seal structure.

[0002]

2. Description of the Related Art Hitherto, the following structure has been widely used as an anti-skid wheel rotation speed detecting device for preventing skid of an automobile. That is, the rotational speed detecting device as described above is composed of a combination of a pulse generating ring and a sensor for detecting the pulse. As a general structure, these are provided independently of each other. And a seal device with a rotation speed detection device in which the sealing means and the rotation speed detection device are integrated, has been developed and put to practical use. Hereinafter, this will be described in detail with reference to the drawings.

An example of a pulse generating ring integrated with such a sealing device will be described with reference to the drawings. As shown in FIG. 3, a pulse is generated on an oil seal (2) fitted to an outer ring (1a). A ring (3) is attached, and a structure in which the pulse generation ring (3) is detected and detected from the outside by a rotation speed detection sensor (4) can be seen. Here, the inside of the bearings (1a, 1b) prevents entry of moisture or foreign matter by the sealing action of the oil seal (2) in which the seal lip (2a) made of an elastic body slides against the inner ring (1b).

[0004]

However, such an oil seal (2) provided with a rotation speed detecting device has the above-mentioned pulse generating ring (3) and rotation speed detecting sensor (4) in the atmosphere on the outermost side. Because of the exposed arrangement, it is in a severe situation where it is directly exposed to scattered water or foreign matter. If this water or mud enters the pulse generating ring (3), it causes rust and the number of rotations is detected. If the performance is significantly reduced or worsened, even foreign matter may adhere to the part, and the foreign matter is generated by the pulse generating ring (3) and the rotation speed detection sensor (4).
If the pulse generation ring (3) or the rotation speed detection sensor (4) enters the narrow portion between the two, the rotation detection device (4) may be damaged by the rotation of foreign matter, causing the rotation detection number to be erroneous or to be destroyed. It appears as a fatal drawback. SUMMARY OF THE INVENTION The present invention has been made in view of the above-described drawbacks, and has as its object to provide a bearing seal having a wheel rotation speed detection device that provides complete protection of a rotation speed detection unit and significantly improves sensing performance and durability.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described with reference to the drawings. As shown in FIG. 1, an elastic body and a reinforcing material for sealing a bearing portion (1a, 1b) such as an automobile wheel are provided. A bearing seal, comprising: a magnetic ring (5a) formed by mixing an elastic body made of synthetic rubber or synthetic resin or the like and a ferromagnetic material such as hard ferrite in a radial direction of a reinforcing ring (5b). Of the reinforcing ring (5a), covering the magnetic ring (5a) from outside.
b) a magnetic ring (5) integrally formed with a seal portion (5d) made of an elastic body connected to a seal lip (5c) disposed on the periphery of the magnetic ring (5); Rotation speed sensor (4) near the seal (5d)
It is characterized by having been deployed.

Further, the wheel bearings (1a, 1a,
b) a bearing seal made of an elastic body and a reinforcing material for detecting the rotation speed and sealing the bearing, and as shown in FIG. 2, the bearing seal is a mixture of an elastic body and a ferromagnetic material. The magnetic ring (5a) formed by the
b) deployed on the outer surface of the radial portion of the magnetic ring (5a)
From the outside, and a seal portion (5) made of an elastic body connected to a seal lip (5c) arranged on the periphery of the reinforcing ring (5b).
d) and a seal lip (6) slidingly contacting the inner peripheral surface of the magnetic ring (5).
a) a rotational speed detection sensor (4) is provided near the seal portion (5d) outside the magnetic ring (5); And

The thickness of the sealing portion (5d) of the magnetic ring (5), which covers the magnetic ring (5a) from the outside, is formed as a thin film having a thickness of 0.05 mm to 2.0 mm. .

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention has the following excellent functions with the above structure. That is, a bearing seal mounted on and fixed to the bearing (1a or 1b) has a magnetic ring (5a) for generating a pulse disposed on a side surface which is a radial portion, and a magnetic ring (5a) provided on the radial portion. 5
Since a) is covered by the seal portion (5d) located outside thereof and is completely shielded from the outside, it is completely protected from intrusion of water or foreign matter from the outside. Further, even if foreign matter enters a narrow portion between the seal portion (5d) formed of an elastic body and the rotation speed detection sensor (4), the foreign matter can be flexibly parryed by an appropriate elasticity,
In the worst case, if it stays here temporarily, its elasticity prevents strong biting, and it is discharged by the subsequent swing-off action, so that the rotation detecting function is not reduced at all. Here, a magnetic ring (5a) that generates a pulse
And the rotational speed detection sensor (4) that senses this, in the best sensing environment not affected by external negative factors (damage, corrosion, deterioration, etc.) at all, guarantees accurate rotational speed detection without malfunction for a long time Can be done.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The magnetic ring (5a) made of an elastic material mixed with a ferromagnetic material according to the present invention is made of a powder or granular material such as a quench-hardening material, a precipitation-hardening material, or a sintered material. Alternatively, it is mixed with an elastic material such as a synthetic resin, and then, if necessary, compression molded in a mold into a reinforcing ring (5b) to which a base treatment and an adhesive have been applied in advance. In the shaping shape of the magnetic ring (5a), the magnetic ring (5a) is provided circumferentially on a radially flat portion of the reinforcing ring (5b), and the seal portion (5d) connected to the seal lip (5c) located outside. Is the magnetic ring (5
It is a desirable shape to completely wrap the entire surface of a) and make a sealed state in which no gap is formed. In addition, the seal portion (5)
As shown in FIG. 1, by extending the peripheral portion of d) to a member to be fitted and mounted and pressing it to the mounting surface, there is an advantage that the sealing force of the mounting surface can be dramatically increased.

As shown in FIG. 2, when a single sealing device is formed by combining the magnetic ring (5) and the sealing member (6), the molding of the sealing member (6) requires a bearing. (In this case 1a) is obtained by providing a seal lip (6a) with an elastic body on the radial peripheral edge of a mounting portion (reinforcement ring made of metal in many cases) to be a mounting portion with (1a). By bringing the magnetic ring (5) into sliding contact with the inner peripheral surface, a combination seal that exerts a strong sealing force on the inside and outside is obtained.

It should be noted that the magnetic ring (5
The seal portion (5d) having a shape enclosing a) from the outside is provided in order to allow the magnetic field generated by the enclosing magnetic ring (5a) to reach the rotation speed detection sensor (4) effectively and maximally.
d) is formed of a non-magnetic elastic material that allows transmission with almost no resistance, and has a thickness of 0.05 mm to 2.0 m.
m, which has a strong protective structure and does not adversely affect the magnetic force. In order to increase the magnetic force, the material of the reinforcing ring (5b) arranged inside is also very important. In this case, use a magnetic material made of an iron material instead of a non-magnetic material such as stainless steel. Is essential.

[0012]

According to the present invention, the magnetic ring (5a) for generating the rotation pulse is completely isolated from the outside air by the seal portion (5d) located on the outer side, so that the foreign matter or lubricating oil is not adhered. To form an accurate and stable magnetic field. Only when the stable magnetic field is present, the sensing performance of the rotation speed detection sensor (4) is exhibited, and the rotation detection with high accuracy can be performed only here. Further, as described above, the magnetic ring (5a) is provided with the reinforcing ring (5d) by the sealing portion (5d) having good molding adhesion.
Since it is fixed to b), it is possible to wipe off the risk of peeling or falling off of the magnetic ring (5a) mixed with a ferromagnetic material having a low adhesive strength.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a cross-sectional view of another embodiment showing a mounted state of the present invention.

FIG. 3 is a sectional view showing a conventional example not using the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Bearing 1a Outer ring 1b Inner ring 2 Oil seal 3 Pulse generating ring 4 Rotation speed detection sensor 5 Magnetic ring 5a Magnetic ring 5b Reinforcement ring 5c Seal lip 5d Seal part 6 Seal member 6a Seal lip

Claims (3)

[Claims] 1. A bearing seal in a wheel bearing portion of an automobile, comprising an elastic body and a reinforcing ring for detecting the rotation speed and sealing the bearing, wherein the bearing seal is a mixture of an elastic body and a ferromagnetic material. A magnetic ring formed by disposing the formed magnetic ring on the outer surface of the reinforcing ring, and integrally forming an elastic seal portion connected to a seal lip disposed on the periphery of the reinforcing ring by covering the magnetic ring from outside. A bearing seal comprising: a ring; and a rotation speed detection sensor disposed close to the magnetic ring from outside. 2. A bearing seal comprising an elastic body and a reinforcing ring for detecting the number of rotations and sealing in a wheel bearing portion of an automobile, wherein the bearing seal is a mixture of an elastic body and a ferromagnetic material. A magnetic ring formed by disposing the formed magnetic ring on the outer surface of the reinforcing ring, and integrally forming an elastic seal portion connected to a seal lip disposed on the periphery of the reinforcing ring by covering the magnetic ring from outside. A bearing having a combination structure in which a ring and a seal member having a seal lip that slides on the inner peripheral surface of the magnetic ring are combined, and a rotation speed detection sensor is disposed close to the magnetic ring from outside. sticker. 3. The bearing seal according to claim 1, wherein a thickness of a sealing portion made of an elastic material which covers the magnetic ring from outside is formed in a thin film having a thickness of 0.05 mm to 2.0 mm.