JP2005331429A - Rolling bearing unit with encoder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rolling bearing unit with an encoder capable of arranging compactly the encoder in a limited space, and capable of preventing water from staying in the encoder. <P>SOLUTION: This rolling bearing unit with the encoder has a bearing part 10 interposed with a rolling element 3 between opposed rolling faces 1a, 2a in an outer member 1 and an inner member 2, and the encoder 12 attached to the inner member 2. The encoder 12 has a support ring 15 engaged with an outer circumference of the inner member 2 and protruded from an end part of the inner member 2. In the support ring 15, a portion projected from the inner member 2 is formed into a groove-shaped bent portion 15b directed toward an axial center side, and a detected part 16 is provided in a side wall part 15bb in a tip side of the bent portion 15b. A drain hole 17 is provided in the groove-shaped bent portion 15b of the support ring 15. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a rolling bearing device with an encoder such as a wheel bearing device or a general bearing device to which an encoder which is a component of a rotation sensor is attached.

  BACKGROUND ART A wheel bearing device for an automobile is provided with a rotation sensor that detects a wheel rotation speed for control of an antilock brake device and various other purposes. FIG. 3A shows a conventional example of a wheel rolling bearing device provided with such a rotation sensor 31. This wheel rolling bearing device includes a rolling element 23 interposed between an outer member 21 that is a stationary member and an inner member 22 that is a rotating member, and the outer member 21 is attached to the vehicle body. By attaching the wheel to the inner member 22, the wheel is rotatably supported with respect to the vehicle body. The rotation sensor 31 includes a ring-shaped encoder 32 attached to the inner member 22 on the rotation side and a sensor 33 attached to the outer member 21 on the fixed side to detect the encoder 32 in a non-contact manner.

The encoder 32 includes, for example, a ring-shaped multipolar magnet 36 and a support ring 35 that supports the multipolar magnet 36, as shown in FIG. Become. The encoder 32 is attached to the inner member 22 by press-fitting the cylindrical portion 35 a of the support ring 35 to the outer periphery of the inner member 22. In order to arrange the encoder 32 in a limited space in the bearing in a compact manner, the support ring 35 has a bent portion 35b bent from one end of the cylindrical portion 35a toward the axial center side, There is a case where the multipolar magnet 36 is fixed to the side wall 35bb on the distal end side of the bent portion 35b.
JP 2003-35718 A

  In the wheel rolling bearing device having the above-described configuration, the support ring 35 of the encoder 32 includes a cylindrical portion 35a that is press-fitted into the inner member 22, and a bent portion that is bent from one end of the cylindrical portion 35a toward the axial center. It is assumed that the bent shape is 35b. For this reason, there is a problem that water W accumulates inside the bent portion 35b of the support ring 35, and the support ring 35 and its peripheral portion are corroded. The shape of the support ring 35 may be a shape in which water does not accumulate, but in that case, it is difficult to arrange the encoder 32 in a limited space on the bearing inboard side.

  An object of the present invention is to provide a rolling bearing device with an encoder in which an encoder can be compactly arranged in a limited space and water can be prevented from collecting in the encoder.

A rolling bearing device with an encoder according to the present invention includes a bearing portion in which rolling elements are interposed between facing rolling surfaces of an outer member and an inner member, and an encoder attached to the inner member. The encoder has a support ring that fits to the outer periphery of the inner member and protrudes from an end of the inner member, and the support ring is a groove in which a portion protruding from the inner member faces the axial center side. It is a rolling bearing device with an encoder, which is a shape-shaped bent portion, and a detected portion is provided on the side wall portion on the distal end side of the bent portion, and a drain hole is provided in the groove-shaped bent portion of the support ring. It is characterized by that.
According to this configuration, the portion protruding from the inner member of the support ring of the encoder is a groove-shaped bent portion facing the axial center side, and the detected portion is provided on the side wall portion on the distal end side of this bent portion. The position where the detected part is provided can be arranged on the outer diameter side as much as possible, and the encoder can be arranged compactly in the limited bearing end side space without causing interference with the peripheral part. In order to enable this compact arrangement, a groove-shaped bent portion is formed in the support ring, so that water easily accumulates as it is, but since a drain hole is provided in the groove-shaped bent portion of this support ring, it has entered from the outside. Even if water flows into the groove-shaped bent portion, it is discharged from the drain hole, and water is prevented from accumulating inside the groove-shaped bent portion.

The support ring may have a rust-proofing layer on the surface. The antirust treatment layer shall cover the inner surface of the drain hole.
By providing the anti-rust treatment layer on the surface of the support ring, the support ring can be made difficult to rust.For example, by forming a drain hole after the anti-rust treatment, the inner surface of the drain hole can be maintained. If it is exposed, the generation of rust proceeds from the exposed part. When the rust-proofing layer is provided up to the inner surface of the drain hole as described above, the progress of rust from the inner surface of the drain hole is prevented.

In this invention, the bearing portion is interposed between an outer member having a double row rolling surface on the inner periphery, an inner member having a rolling surface facing the rolling surface, and the facing rolling surface. It may be a wheel bearing that has a double row rolling element and supports the wheel with respect to the vehicle body.
Wheel bearings are in a harsh environment where they are exposed to salt mud water, and there are severe spatial restrictions due to the location of peripheral components. Therefore, the advantage that the encoder can be compactly arranged in the limited space in the present invention and water can be prevented from being accumulated in the encoder is effectively exhibited, and the encoder support ring accumulates and corrodes with water. Thus, stable rotation detection can be performed.

  A rolling bearing device with an encoder according to the present invention includes a bearing portion in which rolling elements are interposed between facing rolling surfaces of an outer member and an inner member, and an encoder attached to the inner member. The encoder has a support ring that fits to the outer periphery of the inner member and protrudes from an end of the inner member, and the support ring is a groove in which a portion protruding from the inner member faces the axial center side. It is a rolling bearing device with an encoder, which is a shape-shaped bent portion, and a detected portion is provided on the side wall portion on the distal end side of the bent portion, and a drain hole is provided in the groove-shaped bent portion of the support ring. Therefore, the encoder can be compactly arranged in a limited space, and water can be prevented from collecting in the encoder.

  A first embodiment of the present invention will be described with reference to FIG. The rolling bearing device with an encoder according to this embodiment is a wheel bearing device for an automobile that supports a wheel rotatably with respect to a vehicle body, and is classified as a third generation type. In this specification, the side closer to the outer side in the vehicle width direction of the vehicle when attached to the vehicle is referred to as the outboard side, and the side closer to the center of the vehicle is referred to as the inboard side. In FIG. 1A, the left side is the outboard side and the right side is the inboard side.

  This encoder-equipped rolling bearing device is an example applied to the support of a driven wheel, and has an outer member 1 having double-row rolling surfaces 1a on the inner periphery, and rolling surfaces facing the rolling surfaces 1a, respectively. The inner member 2 having 2a and the double row rolling elements 3 interposed between the double row rolling surfaces 1a and 2a constitute a bearing portion 10. The outer member 1 is a member on the fixed side, and is an integral member having a vehicle body mounting flange 1b on the outer periphery. The inner member 2 is a member on the rotation side, and is fitted into a hub wheel 4 having a wheel mounting flange 4a at an outer outboard side end of the outer periphery and an inboard side end of the outer periphery of the hub wheel 4 in a press-fitted state. And an inner ring 5 combined. The inner ring 5 is fastened and fixed in the axial direction with respect to the hub wheel 4 by a flange-shaped crimping portion 4 b formed at the inboard side end of the hub wheel 4. Each of the hub wheel 4 and the inner ring 5 is formed with a row of rolling surfaces 2a of the double row of rolling surfaces 2a. A wheel (not shown) is attached to the wheel attachment flange 4 a of the hub wheel 4 with bolts 9.

  This rolling bearing device is a double row angular contact ball bearing, and contact angles of the rolling surfaces 1a and 2a are formed so as to be back-to-back. The rolling elements 3 are held by a holder 6 for each row. Both ends of the annular space formed between the inner and outer members 2 and 1 are sealed with a pair of sealing means 7 and 8.

  An annular encoder 12 is attached to the outer periphery of the inboard side end of the inner ring 5 that is a component of the inner member 2, and a sensor 13 that covers the encoder 12 in the axial direction covers the outer member 1. It is attached via the member 14. The encoder 12 and the sensor 13 constitute a rotation sensor 11. The encoder 12 is of an axial type, and is a support ring 15 that is fitted into the outer periphery of the inner ring 5 in a press-fitted state and protrudes from the end of the inner ring 5, and a detected portion that is supported by the support ring 15. It consists of a multipolar magnet 16.

  FIG. 1B is an enlarged view of the portion A in FIG. As shown in the figure, the support ring 15 includes a cylindrical portion 15a that is press-fitted into the outer periphery of the inner ring 5, and a groove-shaped bent portion 15b that protrudes from the inner ring 5 of the cylindrical portion 15a and is bent toward the axial center. And become. The groove-shaped bent portion 15b includes an inclined cylinder portion 15ba extending obliquely from one end of the cylindrical portion 15a to the outer diameter side, and a side wall portion 15bb on the distal end side bent from the bearing outer end of the inclined cylinder portion 15ba toward the axial center. The cross-sectional outline V-shape is The multipolar magnet 16 is provided on one side surface of the side wall portion 15bb facing the outside of the bearing.

  The multipolar magnet 16 is a member in which magnetic poles N and S are alternately arranged in the circumferential direction and magnetized, and includes a rubber magnet, a plastic magnet, a sintered magnet, and the like. A plurality of drain holes 17 are distributed in the circumferential direction in the groove-shaped bent portion 15b (specifically, the inclined cylindrical portion 15ba) of the support ring 15. A rust prevention treatment layer 15 c is provided on the surface of the support ring 15. The treatment of the rust prevention treatment layer 15 c is performed after the drainage hole 17 is processed and continuously covers from the surface of the support ring 15 to the inner peripheral surface of the drainage hole 17.

The sensor 13 includes a Hall element or a magnetoresistive element, and detects a magnetic change of the encoder 12 accompanying the rotation of the inner member 2 and outputs it as a sensor signal. The cover member 14 to which the sensor 13 is attached is a cylindrical member whose one end is closed by the end surface portion 14b, and the cylindrical portion 14a is fitted to the inner periphery of the outer side end of the outer member 1 to Cover the inboard side edge. A sensor 13 is attached to the end surface portion 14 b of the cover member 14, and the sensor 13 faces the multipolar magnet 16 of the encoder 12 in the axial direction inside the cover member 14.
A drain hole 18 is formed in a lower position of the cylindrical portion 14 a of the cover member 14 that protrudes from the outer member 1 in the axial direction.

According to the rolling bearing device with an encoder having this configuration, the portion protruding from the inner ring 5 of the support ring 15 of the encoder 12 is the groove-shaped bent portion 15b facing the axial center, and the side wall on the tip side of the groove-shaped bent portion 15b. The detected part 16 is provided in the part 15bb. Therefore, the position where the detected part 16 is provided can be arranged on the outer diameter side as much as possible, and the encoder 12 can be compactly arranged in the limited bearing end side space without causing interference with the peripheral parts such as the caulking part 4b. be able to.
Since the water drain hole 17 is provided in the groove-shaped bent portion 15b of the support ring 15, even if water that has entered from the outside flows into the groove-shaped bent portion 15b, the water is discharged from the water drain hole 17 to form the groove shape. It is possible to prevent water from accumulating inside the bent portion 15b. Further, a rust prevention treatment layer 15c is formed on the surface of the support ring 15, and the inner surface of the drain hole 17 is covered with the rust prevention treatment layer 15c. Therefore, the support ring 15 is prevented from corroding.

  Further, this embodiment is applied to a wheel bearing, and the wheel bearing is in a harsh environment exposed to salt mud water, and there are severe spatial restrictions due to the arrangement of peripheral parts and the like. Therefore, the advantage that the encoder 12 can be compactly arranged in a limited space and water can be prevented from being accumulated in the encoder 12 due to the above configuration is effectively exhibited. Corrosion with accumulated water can be avoided and stable rotation detection can be performed.

  FIG. 2 shows another embodiment of the present invention. In this rolling bearing device with an encoder, in the first embodiment shown in FIG. 1, the groove-shaped bent portion 15b in the support ring 15 of the encoder 12 is formed as shown in an enlarged view in FIG. . The groove-shaped bent portion 15b in this example includes a large-diameter cylindrical portion 15bc that bulges from one end of the cylindrical portion 15a that is a fitting portion to the inner ring 5 to the outer diameter side, and a bearing outer end of the large-diameter cylindrical portion 15bc. It has a U-shaped cross section including a side wall portion 15bb on the distal end side that is bent toward the axial center. The groove-shaped bent portion 15b (specifically, the large-diameter cylindrical portion 15bc) is provided with a plurality of drain holes 17 distributed in the circumferential direction, and the multi-pole magnet 16 is provided on the side wall portion 15bb on the distal end side. This is the same as the case of the first embodiment in that the surface of the support ring 15 is subjected to the treatment for forming the antirust treatment layer 15c, and the antirust treatment layer 15c covers the inner surface of the drain hole 17. It is.

  In addition, although each said embodiment demonstrated the case where it applied to the wheel bearing apparatus, this invention is applicable also to a general bearing, for example, a single row deep groove ball bearing etc.

(A) is sectional drawing of the rolling bearing apparatus with an encoder concerning 1st Embodiment of this invention, (B) is an expanded sectional view of the A section in (A). (A) is sectional drawing of the rolling bearing apparatus with an encoder concerning other embodiment of this invention, (B) is an expanded sectional view of the B section in (A). (A) is sectional drawing of the conventional bearing apparatus, (B) is an expanded sectional view of the C section in (A).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Outer member 1a ... Rolling surface 2 ... Inner member 2a ... Rolling surface 3 ... Rolling body 10 ... Bearing part 12 ... Encoder 15 ... Support ring 15b ... Groove-shaped bending part 15bb ... Side wall part 15c ... Rust prevention process Layer 16 ... Multipole magnet (detected part)
17 ... Drain hole

Claims (3)

  It has a bearing part in which rolling elements are interposed between the rolling surfaces facing the outer member and the inner member, and an encoder attached to the inner member, and the encoder is arranged on the outer periphery of the inner member. The support ring has a support ring that fits and protrudes from the end of the inner member. The support ring has a groove-shaped bent portion that faces the axial center, and the portion protruding from the inner member An encoder-equipped rolling bearing device in which a detected portion is provided on a side wall portion on the front end side, wherein a drainage hole is provided in the groove-shaped bent portion of the support ring. apparatus.   The rolling bearing device with an encoder according to claim 1, wherein the support ring has a rust-proofing layer on a surface, and the rust-proofing layer covers the inner surface of the drain hole. 3. The bearing according to claim 1, wherein the bearing portion includes an outer member having a double-row rolling surface on an inner periphery, an inner member having a rolling surface facing the rolling surface, and an opposing rolling member. A rolling bearing device with an encoder, which is a wheel bearing having a double row rolling element interposed between running surfaces and supporting a wheel with respect to a vehicle body.

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