JP4853722B2 - Rotation detection sensor mounting structure - Google Patents

Description

  The present invention relates to a rotation detection sensor mounting structure.

  Generally, a rotation detection device that detects the rotation speed of a wheel is attached to a hub unit of an automobile. The rotation detection device is used, for example, as information input means for an anti-lock brake system (ABS) of an automobile. For example, the rotation detection device includes a pulsar ring that is fixed to the inner ring side of the hub unit and a sensor that is held by a support ring (annular cover body) that is fixed to the outer ring side, and that rotates as the wheel rotates. There is known a configuration in which a change in rotation is detected by a sensor (see Patent Documents 1 and 2).

JP 2000-221203 A JP 2000-221204 A

  In the technique described in Patent Document 1, a flexible support piece that protrudes in the axial direction and can be bent in the radial direction and a locking piece that protrudes in the axial direction are provided on the support ring, and the flexible support piece and the locking piece. Thus, the sensor is clamped from the radial direction and positioned. In the technique described in Patent Literature 2, a flexible support piece that clamps a sensor pushed in from the radial direction in the axial direction is provided on the support ring, and the sensor and the flexible support piece have irregularities that are positioned in the radial direction and the circumferential direction. They are distributed.

  According to these techniques, the sensor can be easily and quickly attached to and detached from the support ring body by a simple operation. Conventionally, the sensor has been required to have a structure that can be easily attached to and detached from the support ring for maintenance such as repair and replacement. However, the maintenance frequency is relatively low throughout the year, and the advantages of the structure can be enjoyed. There were few opportunities.

  However, since the sensor is mounted with the sensor exposed to the outside, foreign objects may collide with the vehicle during running or weather conditions, and the sensor may fall off the support ring, making it impossible to ensure wheel rotation detection. There is a growing demand for stability and safety rather than workability.

  In addition, as in Patent Document 2, the structure in which the sensor is pressed and fixed by elastic deformation of the flexible support piece causes creep due to heat change or pressing of the spring part over time, and the force for fixing the sensor is reduced. However, there is a possibility that stable output detection of the sensor cannot be secured.

  The present invention has been made in view of the above circumstances, and provides a rotation detection sensor mounting structure that can easily assemble a sensor and that can stably hold the sensor after being assembled. It is in.

Means for Solving the Problems and Effects of the Invention

In order to solve the above problems, the rotation detection sensor mounting structure of the present invention is
The head unit of the hub unit that detects the rotational change of the pulsar ring fixed to the vehicle inner side end in the axial direction of the inner ring of the hub unit that rotatably supports the wheel on the vehicle body is opposed to the pulsar ring. A rotation detection sensor mounting structure for pressing and fixing from a radial direction to a holding portion provided on an annular cover body fixed to an outer ring,
The head portion has a stepped portion and an engaging portion formed on the front end side in the pushing direction from the stepped portion,
The holding portion of the annular cover body holds the head portion so as to be sandwiched from the axial direction by having a resilient piece that is pressed from the vehicle inner side and engages with the engaging portion of the head portion.
The annular cover body has a cylindrical peripheral wall, and an annular wall extending radially inward from the vehicle inner side end of the peripheral wall,
The bullet piece is a bullet base that rises from the inner peripheral edge of the annular wall of the annular cover body, bends radially outward from the upper end of the bullet base, and once enters the vehicle outer side in the middle, A pressing portion that presses and engages the joint portion is formed, and the direction is changed at the pressing portion, and the elastic base portion side and the distal end side are formed in parallel so that the pressing portion serves as a boundary and extends in the pushing direction. And a bullet action part,
In the projecting action portion of the projecting piece, a locking portion that prevents the head portion from coming out radially outward by hooking and locking the step portion of the head portion is formed on the tip side of the pressing portion. characterized in that that.

  According to the present invention, the holding portion of the annular cover body is provided with the elastic piece that holds the head portion of the sensor. The bullet piece includes a pressing portion that presses the head portion from the vehicle inner side, and a locking portion that locks the head portion. On the other hand, the head portion of the sensor has an engaging portion that is pressed by the pressing portion and a step portion that is locked by the locking portion, corresponding to the form of the elastic piece. According to this, when the head portion of the sensor is fixed to the holding portion, the step portion of the head portion is locked to the locking portion of the elastic piece of the holding portion, so that the head portion is in the radial direction (for example, The movement in the direction opposite to the pushing direction) is restricted, and the radial direction can be prevented from coming off.

  Therefore, for example, when a force in the pulling direction is applied due to a foreign object colliding with the sensor head or the like while the vehicle is running, or when the spring force of the projectile piece is reduced due to secular change after mounting, The holding part can stably hold the head part of the sensor even in the case of the occurrence of creep in which the distortion of the head part increases with time under a constant load due to the splinter. As a result, the rotation of the pulsar ring can be detected without any problem. Moreover, since the latching | locking part of an elastic piece is latched by the level | step-difference part of a head part, the load of a press part can be disperse | distributed and generation | occurrence | production of the creep of a head part can be suppressed.

  The locking portion of the holding portion of the bullet piece is formed by folding the tip of the bullet piece toward the vehicle outer side, and the folded portion is hooked on the step portion of the head portion. According to this, since the locking portion is locked to the stepped portion, the locking portion serves as a radial stopper, and the head portion does not easily fall off the holding portion. Further, since the tip of the bullet piece is folded back and the step portion is formed in the head portion, an increase in manufacturing cost can be suppressed. Then, simply by pushing the head portion into the holding portion and disposing the locking portion on the stepped portion, the head portion can be automatically locked by the urging force (pressing force) of the elastic piece, and the assemblability is excellent.

  And since the latching | locking part is formed in the front-end | tip of a bullet piece, it becomes a form which plugs up the contact part of the press part of a bullet piece and the engaging part of a head part, and deposits of foreign materials, such as mud and ice, in the clearance gap Can be prevented. And the part extended to the front-end | tip of the bullet piece becomes a protective wall which covers a head part, and it can prevent effectively that a foreign material collides with a head part during vehicle travel.

  The bullet piece is formed so as to extend along the pushing direction, and a midway portion thereof bulges toward the vehicle outer side to form a pressing portion, and the proximal end side and the distal end side are separated from the pressing portion as a boundary. It is formed in parallel. According to this, since the elastic piece is formed in parallel with the distal end side and the proximal end side across the pressing portion, it can be fixed to the holding portion simply by pushing the head portion straight. Easy to attach.

  Moreover, in the elastic piece, it can be set as the structure by which the length from this press part to a front-end | tip is formed shorter than the length to the press part of the base end side. For example, when the head part is likely to fall against the urging force of the pressing part in the axial direction or vice versa, the tip side is short with the pressing part as a fulcrum, so the rotational movement distance is shortened and the locking part It is possible to prevent the head portion from falling off.

  The holding portion of the annular cover body has a guide piece that guides the head portion that is pushed in along the pushing direction, and the head piece is held by the guide piece and the elastic piece so as to be sandwiched from the axial direction. It can be. According to this, since the head portion of the sensor is guided in the radial direction while being positioned with respect to the axial direction and the circumferential direction by the guide piece of the holding portion, the head portion can be easily assembled to the holding portion. . And since this guide piece has a positioning function with respect to the axial direction, when the bullet piece presses the head portion relatively from the vehicle inner side, the head piece is formed by the bullet piece and the guide piece. Can be held in the axial direction.

In addition, the engaging portion of the elastic piece of the holding portion is arranged along the pushing direction of the stepped portion of the head portion in order to hold the head portion so as to sandwich the head portion from the radial direction when the head portion is fixed to the holding portion. It can comprise as a press locking part to press. In this case, for example, the end portion of the elastic acting portion bulges so as to be folded back in the pushing direction, and the direction changing portion is formed as a head portion. It is good to be comprised so that the level | step-difference part may be pressed. According to this, since the stepped portion of the head portion is relatively pressed along the pushing direction by the locking portion (pressing locking portion) of the elastic piece of the holding portion, the head portion is held in the radial direction. The movement is restricted, and the radial positioning can be prevented and the fixed positioning accuracy can be increased. Moreover, since there are a plurality of parts (for example, two places) where the bullet piece presses the head portion, each pressing force (load) can be more effectively distributed, and the occurrence of creep of the head portion is suppressed. can do. As a result, it is possible to stably detect and output the rotation change of the pulsar ring by the sensor.

  Embodiments of a rotation detection sensor mounting structure according to the present invention will be described below with reference to the drawings. 1 is a view showing an example of a cross-sectional structure of a hub unit equipped with a rotation detection device, FIG. 2 is an exploded perspective view showing an example of a rotation detection device according to an embodiment of the present invention, and FIG. 3 is an example of a head portion. FIG. 4 is a perspective view showing an example of the holding portion, a plan view, a front view and a side view, FIG. 5 is a perspective view showing an example of a state in which the head portion is attached to the holding portion, and FIG. 5 is a side view of FIG. In FIG. 1, the left side in the figure is the vehicle outer side, and the right side in the figure is the vehicle inner side.

  As shown in FIG. 1, the hub unit 1 is interposed between a drive axle 2 and an axle case 3, and rotatably supports a wheel (drive axle 2) (not shown) with respect to the vehicle body (axle case 3). ing. The hub unit 1 includes a hub wheel 4 and a rolling bearing 5.

  The hub wheel 4 has a shaft portion 41 that is spline-fitted to the drive axle 2, and a hub flange 42 that fixes a wheel (not shown) to the vehicle outer side end portion of the shaft portion 41. A bolt insertion hole 43 a through which the bolt 43 is inserted is formed in the hub flange 42, and the wheel is fixed through the bolt 43.

  The rolling bearing 5 is formed of a double-row outward angular ball bearing. Specifically, the rolling bearing 5 uses a part of the outer peripheral surface of the shaft portion 41 of the hub wheel 4 as an inner ring on the vehicle outer side, and is a single unit on the vehicle inner side that is press-fitted and fitted to the outer periphery of the shaft portion 41. An inner ring 51 for a row, an outer ring 52 that is press-fitted into the inner periphery of the axle case 3 and has double row (two rows) raceway grooves, and a plurality of rolling elements 53 as a plurality of rolling elements arranged in a double row. And two crown-shaped cages 54, 54. Therefore, in this embodiment, the outer ring 52 is not rotated and the inner ring 51 (hub wheel 4) is rotated.

  Next, the rotation detection device 6 that is attached to the vehicle inner side end of the hub unit 1 as described above and detects the rotation change of the wheels (not shown) and the drive axle 2 will be described. As shown in FIG. 2, the rotation detection device 6 detects an annular pulsar ring 60 in which magnetic poles (N pole and S pole) having different polarities are alternately arranged in the circumferential direction, and changes in the rotation of the pulsar ring 60. A sensor head portion 70 and an annular cover body 80 for holding the head portion 70 are provided.

  The pulsar ring 60 includes a pulsar ring main body 61 in which N poles and S poles are alternately magnetized, and a pulsar ring support portion 62 that has a cylindrical shape and extends in the form of a flange outward in the radial direction to fix the pulsar ring main body 61 to the end face. Is formed. The pulsar ring 60 is press-fitted and fitted on the outer periphery of the inner ring 51 of the rolling bearing 5 and is fixed at the vehicle inner side end in the axial direction (see FIG. 1).

  The head unit 70 is made of a polymer material such as resin, and is formed by molding a sensor (not shown) such as an IC (Integrated Circuit) chip having a magnetic circuit. The sensor can detect the rotation of the pulsar ring 60 when a voltage is generated in the magnetic circuit due to a change in magnetic flux density caused by the rotation of the pulsar ring 60. A lead wire 79 is drawn out from the head unit 70.

  The annular cover body 80 has a cylindrical peripheral wall 81 and an annular wall 82 extending radially inward from the vehicle inner side end of the peripheral wall 81, and the annular wall 82 has a predetermined circumferential direction. An opening 82a penetrating in the thickness direction is formed at the position, and a holding portion 83 for holding the head portion 70 on the vehicle inner side is provided corresponding to the opening 82a. Thereby, when the head unit 70 is held by the holding unit 83, the rotation of the pulsar ring 60 is detected through the opening 82a. The annular cover body 80 is press-fitted and fitted on the outer periphery of the outer ring 52 of the rolling bearing 5, and is fixed to the vehicle inner side end in the axial direction so as to face the pulsar ring 60 (see FIG. 1). In addition, when attaching the head part 70 to the holding | maintenance part 83, it has the structure which pushes and fixes the head part 70 to the holding | maintenance part 83 from the radial direction (arrow P direction in the figure) of the annular cover body 80.

  Next, detailed aspects of the head unit 70 and the holding unit 83 will be described with reference to FIGS. 3 and 4. As shown in FIG. 3, the head portion 70 includes groove-shaped guide rail portions 72, 72 extending in the longitudinal direction (pushing direction) on the side portions 70a, 70a on both sides, and a bellows-like uneven shape on the upper portion 70b. In the upper part 70b, a stepped part 74 that is locked to a locking part 85e of a bullet piece 85 (to be described later) of the holding part 83 is provided. The positional relationship between the engaging portion 73 and the stepped portion 74 is such that the engaging portion 73 is formed on the distal side in the pushing direction with respect to the stepped portion 74.

  Subsequently, as shown in FIG. 4, the holding portion 83 of the annular cover body 80 is a pair of guides for guiding the sensor head portion 70 pushed in along the pushing direction described above on the vehicle inner side in the axial direction. It has the pieces 84 and 84 and the elastic piece 85 which presses from the vehicle inner side similarly, and engages with the engaging part 73 formed in the head part 70. FIG. Thereby, the head part 70 can be hold | maintained so that it may be pinched | interposed from an axial direction.

  Specifically, the pair of guide pieces 84 and 84 are formed in a longitudinal shape in which the opening portions 82a of the annular wall 82 are sandwiched from the circumferential direction and the opposing end surfaces 84a and 84a extend in the radial direction. (See FIG. 4A).

  The bullet piece 85 includes a bullet base portion 85a that rises from the inner peripheral edge of the annular wall 82, and a bullet action portion 85b that bends in the radial direction (radially outward) from the upper end of the bullet base portion 85a. Yes. And the elastic action part 85b presses the engaging part 73 of the head part 70 from the vehicle inner side and engages with the pressing part 85c and the end part 85d (front end) of the part extended from the pressing part 85c. And a locking portion 85e that hooks and locks the stepped portion 74 of the head portion 70.

  And the bullet action part 85b (bounce piece 85) is formed so that it may extend along the pushing direction of the head part 70, and while the middle part bulges to the vehicle outer side, it forms the press part 85c. The proximal end portion S and the distal end portion T are formed in parallel (parallel to the straight lines L1 and L2) with the pressing portion 85c as a boundary (see FIG. 4D). In other words, the elastic acting portion 85b is formed in a form that once enters the vehicle outer side to form the pressing portion 85c, changes its direction at the pressing portion 85c, and extends to the vehicle inner side. Therefore, when the head unit 70 is attached to the holding unit 83, the bullet piece 85 is formed so as to wrap around from the tip of the head unit 70 to the upper part.

  Further, the elastic piece 85 (the elastic action portion 85b) has a length when the length D from the proximal end side to the pressing portion 85c and the length d from the pressing portion 85c to the end portion 85d (front end) are set. The length d is shorter than the length D (see FIG. 4D).

  In addition, the latching | locking part 85e is formed so that the edge part 85d (front-end | tip) of the elastic piece 85 (ejection action part 85b) may be return | folded to the vehicle outer side. Then, the folded portion is hooked on the stepped portion 74 of the head portion 70.

  Next, a structure for attaching the head unit 70 to the holding unit 83 will be described with reference to FIGS. 5 and 6. As described above, the head unit 70 is fixed at a predetermined position of the holding unit 83 by pushing the head unit 70 toward the holding unit 83 in the radial direction (see FIG. 2). Specifically, the guide rail portion 72 of the head portion 70 is held so that the end portion of the guide piece 84 of the holding portion 83 is fitted. At this time, the end surfaces 84a and 84a of the guide pieces 84 are in contact with or close to the bottoms of the guide rail portions 72 and 72, and the head portion 70 is positioned in the circumferential direction. At the same time, since the end portion of the guide piece 84 enters the groove-shaped guide rail portion 72, positioning in the axial direction is also performed. Accordingly, when the head unit 70 is pushed into the holding unit 83, the head unit 70 is guided in the pushing direction via the guide rail unit 72 and the guide piece 84.

  Further, the pressing portion 85 c of the elastic piece 85 of the holding portion 83 is engaged with the engaging portion 73 of the head portion 70 so as to press. At this time, the pressing portion 85c is engaged with a predetermined recess position of the engaging portion 73, whereby the radial positioning of the head portion 70 with respect to the holding portion 83 is performed. And the latching | locking part 85e formed in the edge part 85d (front-end | tip) of the elastic action part 85b is hooked by the level | step-difference part 74 of the head part 70. FIG. Therefore, the head portion 70 is pressed from the vehicle inner side by the bullet piece 85 and the stepped portion 74 is hooked by the locking portion 85 e of the bullet piece 85 and fixed to the holding portion 83.

  Further, as described above, the base end side portion S and the tip end side portion T (see FIG. 4D) of the elastic acting portion 85b are respectively extended in the radial direction of the annular cover body 80 and formed in parallel. In addition, the guide rail portion 72 and the guide piece 84 are also formed in parallel. Thereby, since each is formed in the form extended in radial direction, the expansion to an axial direction can be suppressed and compactization can be achieved.

  With the above structure, even if the fixing force to hold the sensor decreases due to a decrease in the spring force of the spring part due to aging after mounting on the vehicle and the occurrence of creep due to resin sag, etc., the head part is fixed to the holding part in a stable state. Is possible. As a result, the reliable rotation detection device 6 can be attached to the hub unit 1.

  Next, another embodiment of the rotation detection sensor mounting structure according to the present invention will be described with reference to the drawings. In the following description, portions different from the above-described embodiment will be mainly described, and overlapping portions will be denoted by the same reference numerals, and description thereof will be omitted or simplified. 7 is a perspective view and a side view showing another example 1 of the holding unit, FIG. 8 is a perspective view showing another example 1 with the head unit attached to the holding unit, and FIG. 9 is a side view of FIG. is there.

  As shown in FIG. 7, in the first aspect of another embodiment, the elastic acting portion 85 c of the elastic piece 85 of the holding portion 83 presses the engaging portion 73 of the head portion 70 from the vehicle inner side and engages. It includes a pressing portion 85c to be joined, and a press locking portion 85f (locking portion) that presses the stepped portion 74 of the head portion 70 along the pressing direction to an end portion 85d of the portion extended from the pressing portion 85c. Has been. Thereby, when the head part 70 is fixed to the holding | maintenance part 83, it can hold | maintain so that the head part 70 may be inserted | pinched from radial direction by the press latching | locking part 85f. The pressing locking portion 85f is formed to have a direction changing portion and bulge so that the end portion 85d of the elastic piece 85 (the elastic action portion 85b) is folded back in the vehicle outer side and the pushing direction. Yes. And the direction change part will press the level | step-difference part 74 of the head part 70 relatively.

  Next, as shown in FIGS. 8 and 9, the head unit 70 is held by pushing the head unit 70 in the radial direction (see FIG. 2) toward the holding unit 83, as in the above-described embodiment. The part 83 is fixed at a predetermined position. That is, the pressing portion 85 c of the elastic piece 85 of the holding portion 83 is engaged with the engaging portion 73 of the head portion 70 by pressing (arrow f 1), and the elastic acting portion 85 b is engaged with the stepped portion 74 of the head portion 70. Is engaged by being pressed (arrow f2). At this time, the head portion 70 has a distal end 71 abutting against the inner wall surface of the elastic base portion 85a and is restricted from being pushed in the radial direction, whereby the head locking portion 85f is pressed in the radial direction. It is in a clamped state. Note that the radial pressing of the head portion 70 may be restricted by bringing the side portion 70a of the head portion 70 into contact with the radially outer side surface of the guide piece 84.

  10 is a perspective view showing another example 2 of the holding unit, a plan view and a side view, and FIG. 11 is a perspective view showing another example 2 in a state where the head unit is attached to the holding unit. As shown in FIG. 10, in a second aspect of another embodiment, the elastic action portions 85 b of the elastic pieces 85 of the holding portion 83 are separated by a predetermined interval in the circumferential direction corresponding to the width of the head portion 70. One is formed. As a result, as shown in FIG. 11, each of the elastic acting portions 85 b individually holds the head portion 70, so that fine adjustment according to the shape of the head portion 70 is possible.

  In addition, in this invention, it is not limited to the said Example, It can also be set as the Example variously changed within the range of this invention according to the objective and the use. For example, in the above embodiment, the example in which the rotational speed detection device 6 is used for the hub unit 1 for a driving axle of an automobile has been described. However, the rotational speed detection device 6 may be used for a hub unit for a driven axle.

The figure which shows an example of the cross-sectional structure of the hub unit equipped with the rotation detection apparatus. The disassembled perspective view which shows an example of the rotation detection apparatus which concerns on embodiment of this invention. The perspective view which shows an example of a head part, a top view, a front view, and a side view. The perspective view which shows an example of a holding | maintenance part, a top view, a front view, and a side view. The perspective view which shows an example of the state which attached the head part to the holding | maintenance part. The side view of FIG. The perspective view and side view which show another example 1 of a holding | maintenance part. The perspective view which shows another example 1 of the state which attached the head part to the holding | maintenance part. The side view of FIG. The perspective view, top view, and side view which show another example 2 of a holding | maintenance part. The perspective view which shows another example 2 of the upper body which attached the head part to the holding | maintenance part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Hub unit 2 Drive axle 3 Axle case 4 Hub wheel 5 Rolling bearing 6 Rotation detector 51 Inner ring 52 Outer ring 60 Pulsar ring 70 Head part 73 Engagement part 74 Step part 80 Annular cover body 83 Holding part 85 Bullet piece 85c Press part 85e Locking part 85f Press locking part (locking part)

Claims (6)

A hub portion of a sensor for detecting a rotation change of a pulsar ring fixed to a vehicle inner side end portion in an axial direction of an inner ring of a hub unit that rotatably supports a wheel on a vehicle body so as to face the pulsar ring. A rotation detection sensor mounting structure for pressing and fixing from a radial direction to a holding portion provided in an annular cover body fixed to an outer ring of a unit,
The head portion has a step portion and an engaging portion formed on the front end side in the pressing direction than the step portion,
The holding portion of the annular cover body holds the head portion so as to be sandwiched from the axial direction by having a resilient piece that is pressed from the vehicle inner side and engages with the engaging portion of the head portion.
The annular cover body has a cylindrical peripheral wall, and an annular wall extending radially inward from a vehicle inner side end of the peripheral wall,
The elastic piece is bent from the upper edge of the annular cover body to the outer side of the annular wall of the annular cover body, and is bent radially outward from the upper end of the elastic base portion. A pressing portion that presses and engages the engaging portion of the portion is formed, the direction is changed at the pressing portion, and the elastic base portion side and the distal end side are formed in parallel with the pressing portion as a boundary. A resilient action part extending in the pushing direction,
A locking portion that prevents the head portion from coming out radially outward by hooking and locking the stepped portion of the head portion on the tip side of the pressing portion in the bullet acting portion of the bullet piece. rotation detecting sensor mounting structure characterized in that but is formed.   2. The rotation detection sensor mounting structure according to claim 1, wherein the locking portion is formed such that a tip of the elastic piece is folded back toward a vehicle outer side, and the folded portion is hooked on a stepped portion of the head portion. When the head portion is fixed to the holding portion, the locking portion presses the step portion of the head portion along the pushing direction in order to hold the head portion so as to sandwich the head portion from the radial direction. The rotation detection sensor mounting structure according to claim 1, which is configured as a portion. The pressing locking portion is formed to have an end portion of the elastically acting portion that bulges so as to be folded back in the pushing direction, and has a direction changing portion, and the direction changing portion is formed on the head portion. The rotation detection sensor mounting structure according to claim 3, wherein the rotation detection sensor mounting structure is configured to press the stepped portion. The rotation detection according to any one of claims 1 to 4, wherein in the bullet piece, a length from the pressing portion to the tip is shorter than a length from the bullet base to the pressing portion. Sensor mounting structure.   The holding part has a guide piece for guiding the head part pushed in along the pushing direction, and holds the head part between the guide piece and the bullet piece so as to be sandwiched from the axial direction. Item 6. The rotation detection sensor mounting structure according to any one of Items 1 to 5.

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