JP2012154418A - Wheel supporting structure for motorcycle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wheel supporting structure for a motorcycle, including a ball bearing with a magnetic encoder capable of accurately detecting the number of rotations without sacrificing its assemblability.SOLUTION: The wheel supporting structure for the motorcycle includes the ball bearing with the magnetic encoder, as one of single-row ball bearings in two rows, which includes the magnetic encoder having a face to be detected, instead of a size-limited face perpendicular to the axis, on the inner peripheral face of a cylinder part extending in the axial direction, and a turn-around part turned around from the axial outward end of the cylinder part to the radial inside, the magnetic encoder being provided inside around the two-row bearings and a hub, not on the axial-size-limited fork side. Thus, the wheel supporting structure for the motorcycle is provided, including the ball bearing with the magnetic encoder capable of accurately detecting the number of rotations without sacrificing its assemblability.

Description

  The present invention relates to a wheel support structure for a motorcycle including a ball bearing with a magnetic encoder used for detecting the rotational speed of a wheel of a motorcycle such as a motorcycle or a scooter.

  An anti-lock brake system (ABS) is widely used as a device for stabilizing the running state of an automobile. Conventionally, such ABS has been widely used mainly for four-wheeled vehicles, but in recent years, it has begun to be adopted for motorcycles. As is well known, since it is necessary to determine the rotational speed of the wheel in order to control the ABS, it is possible to incorporate a rotational speed detection device into the wheel bearing ball bearing unit for rotatably supporting the wheel on the suspension device. It has been widely practiced.

However, the structure of the rotational speed detection device for a four-wheeled vehicle cannot be applied to a motorcycle as it is. There are two main reasons (1) and (2) below.
(1) Wheel support ball bearings for motorcycles are considerably smaller than wheel support ball bearings for automobiles.
(2) While many of the wheel bearing ball bearings for four-wheeled vehicles are of the inner ring rotating type, most of the wheel supporting ball bearings for motorcycles are of the outer ring rotating type.

FIG. 7 shows a structure of a portion that rotatably supports a front wheel of a relatively small motorcycle such as a scooter as an example of a wheel support structure of the motorcycle.
The wheel support structure 1 of this motorcycle is fitted into two rows of single-row ball bearings 4 and 4 and inner rings of the two rows of single-row ball bearings 4 and 4, and both ends of the forks 2 and 2 A support shaft 3 coupled to the vehicle body side via a hub, and a hub 6 that is fitted to the outer ring of two rows of single-row ball bearings 4 and 4 and rotatably supports a tire via a wheel 7. Yes.
Inner ring spacers 5a and 5c are provided between the inner rings of the two rows of single row ball bearings 4 and 4 and the forks 2 and 2, and an inner ring spacer 5b is provided between the inner rings of the two rows of single row ball bearings 4 and 4. So that an excessive axial load is not applied to the two rows of single-row ball bearings 4, 4 even if the support shaft 3 is fastened and fixed from both ends via nuts 8.

  On the other hand, a rotational speed detection device using a ball bearing with a magnetic encoder as described in Patent Document 1, for example, has been known as a rotational speed detection device for obtaining the rotational speed of a wheel in order to incorporate ABS in a motorcycle. It has been.

  FIG. 8 shows an example of a ball bearing with a magnetic encoder described in Patent Document 1. This ball bearing 10 with a magnetic encoder includes an outer ring 11 that is a rotating wheel, an inner ring 12 that is a fixed ring, and a plurality of balls 13 that are rolling elements provided between the outer ring 11 and the inner ring 12 so as to be freely rollable. A retainer 14 that rotatably holds the plurality of balls 13 at substantially equal intervals, a sealing plate 15 that is attached to an end portion in the axial direction of the outer ring 11 and that is in sliding contact with the inner ring 12, and magnetically outward in the axial direction. An encoder 9 is attached and fixed, and includes a sealing plate 16 with a magnetic encoder that is attached to the other end portion in the axial direction of the outer ring 11 and that is in sliding contact with the inner ring 12.

  Such a ball bearing with magnetic encoder 10 is replaced with, for example, one of the ball bearings 4 of a pair of ball bearings 4 and 4 incorporated in the structure shown in FIG. Can be detected, that is, the rotational speed of the wheel of the motorcycle.

  FIG. 9 shows an example of a wheel support structure for a motorcycle including such a ball bearing with a magnetic encoder. FIG. 9 shows a simplified shape, but the basic structure is the same as FIG. 7, and the same or equivalent components are denoted by the same reference numerals. The difference from FIG. 7 is that one of the pair of ball bearings 4 and 4 is replaced with a ball bearing 10 with a magnetic encoder. And the magnetic sensor 18 is being fixed to the inner ring spacer 5b which does not rotate so that a magnetic detection surface may oppose the magnetic encoder detected surface of the ball bearing 10 with a magnetic encoder. The output of the magnetic sensor 18 is transmitted to an external arithmetic unit (not shown) via the harness 19, and is appropriately used for, for example, brake control performed by calculating a deviation from rotation speed information determined in advance in the ABS device. Used.

JP 2007-321894 A

  However, as described above, wheel support ball bearings for motorcycles are considerably smaller than wheel support ball bearings for four-wheeled vehicles, and the size of usable magnetic encoders is limited. As a result, the magnetic flux density per pole is smaller than that of a magnetic encoder for a four-wheeled vehicle. Therefore, in order to detect the number of rotations with high accuracy, air that is a gap between the sensor and the magnetic encoder is sacrificed at the expense of assembly. It was necessary to reduce the gap or reduce the number of poles in the circumferential direction of the magnetic encoder at the expense of resolution.

  The present invention has been made to solve the above problems, and the wheel support structure for a motorcycle according to the present invention is fitted to two rows of single row ball bearings and an inner ring of the two rows of single row ball bearings. And a hub that is fitted to the outer ring of the two rows of single row ball bearings and that supports both ends of the tire rotatably via the wheels. And one of the two rows of single row ball bearings is a wheel support structure for a motorcycle that is a ball bearing with a magnetic encoder, and the ball bearing with a magnetic encoder is an outer ring that is a rotating wheel. An inner ring that is a fixed ring, balls that are a plurality of rolling elements that are rotatably arranged in the circumferential direction between the outer ring and the inner ring, and the balls that are rotatable at substantially equal intervals. A retainer, and a seal that is attached to one end of the outer ring in the axial direction and is in sliding contact with the inner ring And an encoder mounting plate attached to the other end in the axial direction of the outer ring and having a magnetic encoder attached and fixed to the inner peripheral surface thereof. The encoder mounting plate is press-fitted into the inner peripheral surface of the outer ring and is A cylindrical portion extending in the direction, a magnetic encoder fixedly attached to an inner peripheral surface of the cylindrical portion, and a folded portion folded back radially inward from an axially outer end of the cylindrical portion, and mounting the magnetic encoder The plate is placed on the other single row ball bearing side in the axial direction, and the sealing plate is placed on the opposite side of the other single row ball bearing in the axial direction. A magnetic sensor fixed to a non-rotating member is provided so that the surfaces face each other.

In the wheel support structure for a motorcycle of the present invention, the detected surface of the magnetic encoder of the ball bearing with a magnetic encoder, which is one of the two rows of single row ball bearings, does not face the shaft with a limited dimension, but extends in the axial direction. Since the axial length can be increased by providing it on the inner circumferential surface of the cylinder, it is possible to increase the area per pole.
In addition, since the cylindrical portion extends in the axial direction, there is a concern about a decrease in rigidity, but by providing a folded portion that is turned back radially inward from the axially outer end of the cylindrical portion, it is possible to suppress the decrease in rigidity. It is possible.
In addition, by providing the magnetic encoder on the inner side surrounded by the two rows of bearings and the hub instead of the fork side, which is dimensionally limited in the axial direction, it is possible to use the space between the two bearings. Therefore, it is possible to provide a wheel support structure for a motorcycle including a ball bearing with a magnetic encoder capable of accurately detecting the rotation speed without sacrificing assembling performance.

1 is a cross-sectional view of a main part for explaining a wheel support structure of a motorcycle capable of detecting a rotation speed of a wheel according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of a main part for explaining a ball bearing with a magnetic encoder used in the wheel support structure of the motorcycle shown in FIG. 1. FIG. 6 is a cross-sectional view of a main part for explaining another example of a ball bearing with a magnetic encoder used in a wheel support structure for a motorcycle. FIG. 6 is a cross-sectional view of a main part for explaining another example of a ball bearing with a magnetic encoder used in a wheel support structure for a motorcycle. FIG. 6 is a cross-sectional view of a main part for explaining another example of a ball bearing with a magnetic encoder used in a wheel support structure for a motorcycle. FIG. 6 is a cross-sectional view of a main part for explaining another example of a ball bearing with a magnetic encoder used in a wheel support structure for a motorcycle. It is sectional drawing which shows an example of the wheel support structure of the conventional motorcycle. It is sectional drawing which shows an example of the conventional ball bearing with a magnetic encoder. It is sectional drawing which shows an example of the wheel support structure of the motorcycle provided with the conventional ball bearing with a magnetic encoder.

  The motorcycle wheel support structure 20 capable of detecting the rotational speed of the wheel shown in FIG. 1 according to the embodiment of the present invention is, for example, a pair of motorcycle wheel support structures 1 incorporated in the motorcycle shown in FIG. Instead of one of the ball bearings 4, 4, a ball bearing 21 a with a magnetic encoder as shown in FIG. 2 is incorporated between the outer peripheral surface of the support shaft 3 and the inner peripheral surface of the hub 6, and the magnetic The sensor 18 is fixed to the inner ring spacer 5 b that does not rotate so that the sensor detection surface faces the detection surface of the magnetic encoder 34.

  Although FIG. 1 shows a simplified shape, the basic structure is the same as FIG. 7, and the same or equivalent components are denoted by the same reference numerals.

  As shown in FIGS. 1 and 2, the ball bearing 21 a with a magnetic encoder is fixed to the support shaft 3 and the outer ring 22 a that is a rotating wheel that rotates together with the wheel 7 by being fitted inside the hub 6. An inner ring 24a that is a stationary ring that does not rotate, a plurality of balls 26 that are a plurality of rolling elements that are rotatably arranged in the circumferential direction between the outer ring 22a and the inner ring 24a, and the plurality of balls 26 are arranged at substantially equal intervals. A retainer 27 that is rotatably held, a sealing plate 28 that is attached to one end of the outer ring 22a in the axial direction and is in sliding contact with the inner ring 24a, and is attached to the other end of the outer ring 22a in the axial direction. And an encoder mounting plate 35a in which a cylindrical magnetic encoder 34, in which N poles and S poles are alternately and continuously arranged, is attached and fixed to the inner peripheral surface.

  The sealing plate 28 is formed in an annular shape by covering a core metal 29 as a reinforcing member with an elastic member 30. A seal fixing groove 23 is formed on the inner peripheral surface of one end of the outer ring 22a in the axial direction. By fitting the outer peripheral portion of the sealing plate 28 into the seal fixing groove 23 using the elasticity of the elastic member, The sealing plate 28 is fixed to the outer ring 22a. Further, a seal groove 25 is formed on the outer peripheral surface of one end in the axial direction of the inner ring 24 a facing the seal fixing groove 23, and a seal lip provided on the inner peripheral portion of the sealing plate 28 in the seal groove 25. 31 is in sliding contact.

  The encoder mounting plate 35a is press-fitted into the inner peripheral surface 32a of the other end in the axial direction of the outer ring 22a (the end opposite to the end where the sealing plate 28 is mounted) and is axially outward (from the outer ring 22a). The cylindrical portion 36 extending to the far side), the magnetic encoder 34 attached and fixed to the inner peripheral surface of the cylindrical portion 36, and the axially outward of the cylindrical portion 36 (the side far from the outer ring 22a). It consists of a folded portion 37 and is fixed so as to rotate integrally with the outer ring 22a. The folded-back portion 37 suppresses a decrease in rigidity due to the length of the cylindrical portion 36, and also serves as a pressing portion when the encoder mounting plate 35a is press-fitted into the outer ring 22a.

  As shown in FIG. 1, such a ball bearing with magnetic encoder 21 a has an outer peripheral surface of the support shaft 3 and an inner periphery of the hub 6 so that the magnetic encoder 34 is on the side of the ball bearing 4 that is the other ball bearing. Built in between the faces.

The magnetic sensor 18 detects the rotation of the outer ring 22a by detecting, as a magnetic pulse, a change in magnetic flux density generated on the detected surface of the magnetic encoder 34 that rotates integrally with the outer ring 22a.
The inner ring spacer 5b to which the magnetic sensor 18 is attached and the support shaft 3 are provided with a hole or groove through which the harness 19 is passed, and the harness 19 is drawn out without passing through the rotating part. . Then, the rotational speed information detected by the magnetic sensor 18 is transmitted to an external arithmetic unit (not shown) by the harness 19 and, for example, a deviation from rotational speed information predetermined in the ABS device is calculated. Is suitably used for brake control or the like performed by.

  In FIG. 1, the magnetic sensor 18 is fixed to the inner ring spacer 5b that does not rotate. However, if the sensor detection surface can be disposed with an appropriate gap so as to face the detection surface of the magnetic encoder 34, the support shaft If it is a member which does not rotate, such as fixing directly to 3, it may be fixed anywhere.

FIGS. 3-6 is principal part sectional drawing for demonstrating another example of the ball bearing with a magnetic encoder used for the wheel support structure of a motorcycle. The ball bearings with magnetic encoder 21b, 21c, 21d, and 21e shown in FIGS. 3 to 6 are motorcycles that can detect the rotational speed of the wheel as shown in FIG. 1, as with the ball bearing with magnetic encoder 21a shown in FIG. The wheel support structure 20 can be used.
3 to 6, the basic structure is the same as that of FIG. 2, and the same or equivalent components are denoted by the same reference numerals.

  3 differs from the ball bearing with magnetic encoder 21a shown in FIG. 2 only in the shape of the encoder mounting plate 35b. The encoder mounting plate 35 b has folded portions 37 formed at both ends in the axial direction of the cylindrical portion 36. As a result, the encoder mounting plate 35b does not have directionality when press-fitted into the outer ring 22a, so that workability can be improved.

The ball bearing with magnetic encoder 21c shown in FIG. 4 is an embodiment in which the area per pole of the magnetic encoder 34 is further increased with respect to the ball bearing with magnetic encoder 21b shown in FIG.
On the outer ring 22b of the ball bearing with magnetic encoder 21c, the encoder mounting plate 35c is press-fitted and fixed to the inner peripheral surface 32b of the other end in the axial direction (the end opposite to the end where the sealing plate 28 is attached). For this purpose, a press-fit step portion 40 having a diameter larger than that of the inner peripheral surface 32b is provided.
The encoder mounting plate 35c includes a cylindrical portion 36 having a larger diameter than the inner peripheral surface 32b that is press-fitted into the press-fitting step portion 40 of the outer ring 22b and extends outward in the axial direction (the side far from the outer ring 22a), and the inner peripheral surface of the cylindrical portion 36 The magnetic encoder 34 is fixedly attached to the cylindrical portion 36, and the folded portions 37 and 37 are folded back radially inward at both axial ends of the cylindrical portion 36, and are fixed so as to rotate integrally with the outer ring 22b. The encoder mounting plate 35c can be increased in area per pole of the magnetic encoder 34 by making it as large as the strength of the outer ring 22b and the inner diameter of the hub 6 allow.

The ball bearing with magnetic encoder 21d shown in FIG. 5 differs from the ball bearing with magnetic encoder 21c shown in FIG. 4 only in the shape of the encoder mounting plate 35d.
The encoder mounting plate 35d is folded back inward in the radial direction at the cylindrical portion 36, the magnetic encoder 34 attached and fixed to the inner peripheral surface of the cylindrical portion 36, and the axially outward of the cylindrical portion 36 (the side far from the outer ring 22b). And a shield portion 38a that is folded back inward in the axial direction of the cylindrical portion 36 (on the side that is press-fitted into the outer ring 22b) and extends radially inward and has an inner diameter side end face that is close to the outer peripheral surface of the inner ring 24a. .
A labyrinth seal can be formed between the shield part 38a and the outer peripheral surface of the inner ring 24a to prevent the lubricant such as grease from flowing out of the bearing 21d. Therefore, it is necessary to separately add a seal for suppressing the grease outflow. No.

The ball bearing with magnetic encoder 21e shown in FIG. 6 is an embodiment in which the sealing performance is improved with respect to the ball bearing with magnetic encoder 21d shown in FIG.
The encoder mounting plate 35e is folded inward in the radial direction at the cylindrical portion 36, the magnetic encoder 34 attached and fixed to the inner peripheral surface of the cylindrical portion 36, and the axially outward of the cylindrical portion 36 (the side far from the outer ring 22b). A folded portion 37, a shield portion 38b that is folded inward in the axial direction of the cylindrical portion 36 (the side that is press-fitted into the outer ring 22b) and extends radially inward, and a seal lip provided on the inner peripheral portion of the shield portion 38b 39.
A seal groove 33 similar to the seal groove 25 on the other end surface is formed on the outer peripheral surface of the end of the inner ring 24b of the ball bearing with magnetic encoder 21e on the axial encoder side, and the seal lip 39 is formed in the seal groove 33. It is in sliding contact. With this configuration, the sealing performance can be further improved as compared with the ball bearing with magnetic encoder 21d shown in FIG.

As described above, according to the present invention, the detected surface of the magnetic encoder of the ball bearing with a magnetic encoder, which is one of the two rows of single row ball bearings, does not face the shaft with limited dimensions, but extends in the axial direction. Since the axial length can be increased by providing it on the inner circumferential surface of the cylinder, it is possible to increase the area per pole.
In addition, by providing the magnetic encoder on the inner side surrounded by the two rows of bearings and the hub instead of the fork side, which is dimensionally limited in the axial direction, it is possible to use the space between the two bearings. Can be used as a wheel support structure for a motorcycle including a ball bearing with a magnetic encoder capable of accurately detecting the number of rotations without sacrificing assembly.

1 Wheel support structure for motorcycles
2 forks
3 Support shaft
4 Single row ball bearing
5a, 5b, 5c Inner ring spacer
6 Hub
7 wheel
8 Nut
9 Magnetic encoder
10 Ball bearing with magnetic encoder
11 Outer ring
12 Inner ring
13 balls
14 Cage
15 Sealing plate
16 Sealing plate with magnetic encoder
17 Wheel support structure for motorcycles
18 Magnetic sensor
19 Magnetic sensor harness
20 Motorcycle wheel support structure
21a, 21b, 21c, 21d, 21e Ball bearing with magnetic encoder
22a, 22b Outer ring
23 Seal fixing groove
24a, 24b Inner ring
25 Seal groove
26 balls
27 Cage
28 Sealing plate
29 Core
30 Elastic member
31 Seal lip
32a, 32b Inner surface of outer ring
33 Seal groove
34 Magnetic encoder
35a, 35b, 35c, 35d, 35e Encoder mounting plate
36 Cylindrical part
37 Folding part
38a, 38b Shield part
39 Seal lip
40 Press-fitting step

Claims (3)

Two rows of single row ball bearings, a support shaft that is fitted to the inner ring of the two rows of single row ball bearings and whose both ends are coupled to the vehicle body via forks, and the two rows of single row balls A motorcycle fitted with an outer ring of the bearing and rotatably supporting a tire via a wheel, wherein one of the two rows of single row ball bearings is a ball bearing with a magnetic encoder. Wheel support structure,
The ball bearing with magnetic encoder is
An outer ring that is a rotating wheel;
An inner ring that is a fixed ring,
Balls that are a plurality of rolling elements arranged to be freely rollable in the circumferential direction between the outer ring and the inner ring,
A holder for rotatably holding the plurality of balls at substantially equal intervals;
A sealing plate attached to one end in the axial direction of the outer ring and in sliding contact with the inner ring;
An encoder mounting plate attached to the other end in the axial direction of the outer ring and having a magnetic encoder attached and fixed to the inner peripheral surface thereof;
The encoder mounting plate is
A cylindrical portion that is press-fitted into the inner peripheral surface of the outer ring and extends axially outward;
A magnetic encoder attached and fixed to the inner peripheral surface of the cylindrical portion;
A folded portion folded back radially inward from the axially outer end of the cylindrical portion,
The magnetic encoder mounting plate is disposed on the other side of the single-row ball bearing in the axial direction, and the sealing plate is disposed on the side opposite to the other single-row ball bearing in the axial direction;
A wheel support structure for a motorcycle, comprising: a magnetic sensor fixed to a non-rotating member so that the sensor detection surface faces the detection surface of the magnetic encoder. The encoder mounting plate is
A cylindrical portion that is press-fitted into the inner peripheral surface of the outer ring and extends axially outward;
A magnetic encoder attached and fixed to the inner peripheral surface of the cylindrical portion;
A folded portion folded back radially inward from the axially outer end of the cylindrical portion;
2. The motorcycle wheel according to claim 1, further comprising: a shield portion that is folded back at an axially inner end of the cylindrical portion and extends radially inward, and an inner diameter side end surface is close to an outer peripheral surface of the inner ring. Support structure. The encoder mounting plate is
A cylindrical portion that is press-fitted into the inner peripheral surface of the outer ring and extends axially outward;
A magnetic encoder attached and fixed to the inner peripheral surface of the cylindrical portion;
A folded portion folded back radially inward from the axially outer end of the cylindrical portion;
A seal portion that is folded back at the inner end in the axial direction of the cylindrical portion and extends radially inward and has an inner diameter side end surface close to the outer peripheral surface of the inner ring, and a seal that is in sliding contact with the inner ring. The wheel support structure for a motorcycle according to claim 1 or 2, comprising a lip.

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