JP2012228934A - Steering device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a steering device provided with a rolling bearing rotatably journaling a steering shaft, suited to a steering device wherein an upper column engages with a lower column slidably in the axial direction, and increased in the maneuvering stability of a steering wheel during high speed traveling.SOLUTION: The outer circumferential face 312 of a female steering shaft 31 is fastened by the cylindrical face 661 of a bush 6, because of the elastic force of an O-ring 64. Accordingly, a given friction force is caused between the outer circumferential face 312 of the female steering shaft 31 and a cylindrical face 661 of the bush 6, to increase the maneuvering stability of the steering wheel during high speed traveling. Since the O-ring 64 is pressed by the inner peripheral face 212 of a first lower column 21 to be in a crushed state, vibration of the female steering shaft 31 is absorbed by the O-ring 64, and the transmission of the vibration of an axle to the steering wheel can be prevented.

Description

  The present invention relates to a steering device, in particular, a telescopic steering device or a secondary collision in which an upper column and a lower column are slidably fitted in an axial direction to adjust a telescopic position of a steering wheel. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steering device that collapses to the front side of a vehicle body and absorbs an impact load, and includes a rolling bearing that rotatably supports a steering shaft.

  Since the rolling bearing that rotatably supports the steering shaft has a small frictional resistance and a stable frictional resistance, an extremely smooth steering operation can be performed. However, since rolling bearings have low vibration absorption characteristics, axle vibrations caused by road surface undulations during high-speed driving are transmitted to the steering wheel as they are, and the steering wheel slightly vibrates in the rotational direction and vertical direction, resulting in steering stability. There is a problem that decreases.

  In the steering device of Patent Document 1, a sliding bearing is attached between an inner peripheral surface of a column and an outer peripheral surface of a steering shaft via an elastic body, thereby applying a frictional resistance to the steering shaft to thereby vibrate the steering wheel. Absorbs and improves steering stability. However, the steering device of Patent Document 1 is applied to a slide bearing, and is not applied to a rolling bearing.

  In the steering device disclosed in Patent Document 2, the outer peripheral surface of the rear end of a steering shaft that is rotatably supported by a rolling bearing is attached to a steering shaft by attaching a cylindrical friction addition member via an O-ring. It gives resistance and absorbs vibration of the steering wheel to improve steering stability. However, the steering device of Patent Document 2 is difficult to apply to a steering device in which an upper column and a lower column are fitted so as to be slidable in the axial direction.

JP-A-9-303387 JP 2005-53292 A

  The present invention is suitable for a steering device that includes a rolling bearing that rotatably supports a steering shaft, and in which an upper column and a lower column are slidably fitted in an axial direction, and improves steering stability of a steering wheel during high-speed traveling. It is an object to provide an improved steering apparatus.

  The above problem is solved by the following means. In other words, the first invention provides the upper column with a lower column, an upper column fitted to the lower column so as to be relatively slidable in the axial direction, and a rolling bearing provided on the upper side of the upper column. A female steering shaft that is rotatably supported and has a steering wheel mounted on the rear side of the vehicle body, and is rotatably supported on the lower column by a rolling bearing provided on the lower side of the lower column. A male steering shaft that engages so as to be able to move relative to the direction and transmit rotational torque to transmit the rotation of the steering wheel to the wheels, an inner peripheral surface of the lower column, and an outer peripheral surface of the female steering shaft; A hollow cylindrical bush having an axial slit formed between the bush and the bush. An elastic member that is inserted between the outer peripheral surface of the nut and the inner peripheral surface of the lower column, urges the bush in the direction of reducing the diameter, and presses the inner peripheral surface of the bush against the outer peripheral surface of the female steering shaft. This is a steering device.

  The steering device of the present invention is provided on a lower side of a lower column, a female steering shaft that is rotatably supported on the upper column by a rolling bearing provided on the upper side of the upper column, and a steering wheel is mounted on the rear side of the vehicle body. The rotation of the steering wheel is transmitted to the wheel by being rotatably supported on the lower column by the rolling bearing and engaged with the female steering shaft so as to be relatively movable in the axial direction and capable of transmitting rotational torque. A male steering shaft, a hollow cylindrical bush having an axial slit formed between the outer peripheral surface of the female steering shaft and the inner peripheral surface of the lower column, and the inner surface of the outer peripheral surface of the bush and the lower column The bush is inserted between the outer peripheral surface and the bush is biased in the direction of reducing the diameter, and the inner peripheral surface of the bush is And an elastic member that presses the outer peripheral surface of the ring shaft.

  Therefore, a predetermined frictional force is generated between the outer peripheral surface of the female steering shaft and the inner peripheral surface of the bush, so that the sitting of the steering wheel is improved, and the steering stability of the steering wheel during high-speed traveling is improved. Further, the vibration of the female steering shaft is absorbed by the elastic member, and the vibration of the axle is hardly transmitted to the steering wheel, so that the steering feeling is improved.

1 is an overall perspective view showing a state in which a steering device according to an embodiment of the present invention is attached to a vehicle. 1 is a front view of a part of a main part of a steering device according to an embodiment of the present invention. (A) is an expanded sectional view of the bush vicinity of the Example of this invention, (b) is the P section expanded sectional view of (a). (A) is an enlarged front view of the bush of the Example of this invention, (b) is AA sectional drawing of (a).

  FIG. 1 is an overall perspective view showing a state in which a steering device 101 according to an embodiment of the present invention is attached to a vehicle. As shown in FIG. 1, a hollow cylindrical column 102 is attached to a vehicle body, and a steering shaft 104 is rotatably supported on the column 102. A steering wheel 103 is mounted on the steering shaft 104 at the right end (rear side of the vehicle body), and an intermediate shaft 106 is connected to the left end of the steering shaft 104 (front side of the vehicle body) via a universal joint 105.

  The intermediate shaft 106 includes a solid intermediate inner shaft 106a in which a male spline is formed and a hollow cylindrical intermediate outer shaft 106b in which a female spline is formed. The male spline of the intermediate inner shaft 106a is connected to the intermediate outer shaft. The female spline 106b is fitted so as to be extendable (slidable) and capable of transmitting rotational torque.

  Furthermore, the vehicle body rear side of the intermediate outer shaft 106 b is connected to the universal joint 105, and the vehicle body front side of the intermediate inner shaft 106 a is connected to the universal joint 107. A pinion that meshes with a rack (not shown) of the steering gear 108 is connected to the universal joint 107.

  When the driver rotates the steering wheel 103, the rotational force is transmitted to the steering gear 108 via the steering shaft 104, the universal joint 105, the intermediate shaft 106, and the universal joint 107, and the tie rod is transmitted via the rack and pinion mechanism. 109 can be moved to change the steering angle of the steering wheel 110.

  FIG. 2 is a partially sectional front view showing the main part of the steering device of the embodiment of the present invention, FIG. 3A is an enlarged sectional view of the vicinity of the bush of the embodiment of the present invention, and FIG. These are the P section expanded sectional views of Drawing 3 (a). As shown in FIGS. 2 and 3, the upper column (outer column) 1 is fixed to a vehicle body (not shown) by an upper vehicle body mounting bracket 52. On the vehicle body front side (left side in FIG. 2) of the hollow cylindrical upper column 1, the outer peripheral surface of the hollow cylindrical first lower column (inner column) 21 is axially disposed on the inner peripheral surface of the upper column 1. The telescopic position can be adjusted closely.

  On the vehicle body front side (left side in FIG. 2) of the first lower column 21, the outer peripheral surface 213 of the first lower column 21 and the inner peripheral surface 221 of the hollow cylindrical second lower column (inner column) 22 are provided. However, they are closely fitted so that they can move in the axial direction. A vehicle body front end of the second lower column 22 is pivotally fixed to a vehicle body (not shown) by a lower vehicle body mounting bracket 51. The inner peripheral surface 221 of the second lower column 22 is clamped to the outer peripheral surface 213 of the first lower column 21 by caulking, and when an impact force is applied to the front side of the vehicle body during a secondary collision, the caulking portion is deformed. Thus, the first lower column 21 moves in a collapsible manner relative to the second lower column 22 toward the front side of the vehicle body.

  A female steering shaft (upper steering shaft) 31 is inserted into the shaft center of the upper column 1 and is inserted into the right end (upper side) of the inner peripheral surface of the upper column 1 by a rolling bearing (not shown). The right end (upper side) of 31 is rotatably supported. A steering wheel 103 shown in FIG. 1 is mounted on the right end (rear side of the vehicle body) of the female steering shaft 31.

  A rolling bearing (deep groove ball bearing) in which a male steering shaft 32 is inserted into the inner peripheral surface 221 of the second lower column 22 and press-fitted into the left end (lower side) of the inner peripheral surface 221 of the second lower column 22. 41, the left end (lower side) of the male steering shaft 32 is rotatably supported. A male spline 321 is formed on the right side of the male steering shaft 32. The spline engagement is such that the female spline 311 formed on the left side of the female steering shaft 31 can move relative to the axial direction and transmit rotational torque. doing.

  As shown in FIGS. 3A and 3B, the inner peripheral surface of the first lower column 21 has a mounting surface 212 formed over a predetermined length from the left end (lower side) of the first lower column 21. ing. An inner peripheral surface 211 is formed adjacent to the right end (upper side) of the mounting surface 212. The mounting surface 212 and the inner peripheral surface 211 are both cylindrical, and the inner diameter of the inner peripheral surface 211 is smaller than that of the mounting surface 212. A step 214 is formed between the mounting surface 212 and the inner peripheral surface 211. A synthetic resin bush 6 shown in FIG. 4 is inserted between the outer peripheral surface 312 of the female steering shaft 31 and the spline fitting portion and the mounting surface 212 of the first lower column 21 when viewed in the axial direction. Yes. As shown in FIG. 4, the bush 6 has a hollow cylindrical shape, and one slit 61 is formed over the entire length in the axial direction.

  On the outer peripheral surface 62 of the bush 6, an annular groove 63 is formed in the middle in the axial direction (left-right direction in FIG. 3B), and the annular groove 63 has a circular cross section and an annular O-ring (elastic member). 64 is inserted. The O-ring 64 is made of an elastic material such as synthetic rubber.

  On the inner peripheral surface 66 of the bush 6, a cylindrical surface 661 is formed at an intermediate portion in the axial direction, and tapered surfaces 662 and 662 are formed at both end portions in the axial direction. The tapered surfaces 662 and 662 are formed so that the axial end portions are inclined in a direction away from the axial center. In a state before the bush 6 is inserted into the mounting surface 212 of the first lower column 21, the inner diameter dimension of the cylindrical surface 661 of the bush 6 is slightly larger than the outer diameter dimension of the outer peripheral surface 312 of the female steering shaft 31. ing.

  When the bush 6 is inserted into the mounting surface 212 of the first lower column 21, the bush 6 is reduced in diameter with the interval between the slits 61 being narrowed, and can be easily inserted into the inner peripheral surface 211 of the first lower column 21. . The bush 6 having a reduced diameter is inserted into the mounting surface 212 of the first lower column 21, and a step portion (see FIG. 3B) 214 formed on the inner periphery of the first lower column 21 is inserted into the bush 6. It abuts on one end face. Thereafter, a C-shaped retaining ring or a retaining ring 7 such as a C-ring is fitted in the inner circumferential groove 215 formed on the mounting surface 212 and is brought into contact with the other end surface of the bush 6 so that the bush 6 moves in the axial direction. Is blocked.

  Further, the O-ring 64 is pressed against the inner peripheral surface 211 of the first lower column 21 and is crushed. Due to the elastic force of the O-ring 64, the inner diameter dimension of the cylindrical surface 661 of the bush 6 is reduced. It is slightly smaller than the outer diameter dimension. Since the O-ring 64 is disposed at the same axial position as the cylindrical surface 661, the cylindrical surface 661 of the bush 6 can be accurately reduced in diameter by the elastic force of the O-ring 64. In addition, since the slit 61 is formed in the bush 6 over the entire length in the axial direction, the cylindrical surface 661 is uniformly reduced in diameter in the axial direction, and the influence on the sliding resistance when the steering shaft is rotated. Can be made insensitive.

  Thereafter, the upper column 1 incorporating the female steering shaft 31 is externally fitted to the first lower column 21. Further, the second lower column 22 incorporating the male steering shaft 32 is externally fitted to the first lower column 21 and is tightened to the outer peripheral surface 213 of the first lower column 21 by caulking.

  Since the inner peripheral surface 66 of the bush 6 has tapered surfaces 662 and 662 at both ends in the axial direction, the outer peripheral surface 312 of the female steering shaft 31 is guided by the tapered surface 662 and the cylindrical surface of the bush 6. 661 is smoothly inserted. Further, since tapered surfaces 662 and 662 are formed at both ends of the bush 6 in the axial direction, the outer peripheral surface 312 of the female steering shaft 31 slides smoothly along the cylindrical surface 661 of the bush 6 when adjusting the telescopic position. Can move.

  When the outer peripheral surface 312 of the female steering shaft 31 is inserted into the cylindrical surface 661 of the bush 6, the outer peripheral surface 312 of the female steering shaft 31 is fastened by the cylindrical surface 661 of the bush 6 by the elastic force of the O-ring 64. The axial position where the bush 6 clamps the outer peripheral surface 312 of the female steering shaft 31 is the spline engaging portion between the male steering shaft 32 and the female steering shaft 31.

  Therefore, a predetermined frictional force is generated between the outer peripheral surface 312 of the female steering shaft 31 and the cylindrical surface 661 of the bush 6 to improve the sitting of the steering wheel 103, and the steering stability of the steering wheel 103 during high-speed traveling. Will improve. Further, since the O-ring 64 is pressed and crushed by the inner peripheral surface 211 of the first lower column 21, the vibration of the female steering shaft 31 is absorbed by the O-ring 64, and the vibration of the axle is absorbed by the steering wheel. Since it becomes difficult to transmit to 103, a steering feeling improves.

  In the above embodiment, the O-ring 64 having a circular cross section is used. However, an annular ring made of synthetic rubber and having an X-shaped cross section or a U-shaped cross section may be used. In the above-described embodiment, the bush 6 is formed with one slit 61 over the entire length in the axial direction, but slits shorter than the axial length of the bush 6 are formed at a plurality of locations on the circumference. May be.

  In the above embodiment, the upper column is an outer column and the lower column is applied to the inner column steering device. However, the upper column may be an inner column and the lower column may be applied to the outer column steering device.

  In the above embodiment, the upper steering shaft is a female steering shaft, and the lower steering shaft is applied to a steering device of a male steering shaft. However, the upper steering shaft is a male steering shaft, and the lower steering shaft is a female steering shaft. You may apply to the steering device of a shaft.

DESCRIPTION OF SYMBOLS 101 Steering device 102 Column 103 Steering wheel 104 Steering shaft 105 Universal joint 106 Intermediate shaft 106a Intermediate inner shaft 106b Intermediate outer shaft 107 Universal joint 108 Steering gear 109 Tie rod 110 Steering wheel 1 Upper column (outer column)
21 First lower column (inner column)
211 Inner peripheral surface 212 Mounting surface 213 Outer peripheral surface 214 Stepped portion 215 Inner peripheral groove 22 Second lower column (inner column)
221 Inner peripheral surface 31 Female steering shaft (upper steering shaft)
311 Female spline 312 Outer peripheral surface 32 Male steering shaft (lower steering shaft)
321 Male spline 41 Rolling bearing (Deep groove ball bearing)
51 Lower body mounting bracket 52 Upper body mounting bracket 6 Bushing 61 Slit 62 Outer peripheral surface 63 Annular groove 64 O-ring (elastic member)
66 Inner peripheral surface 661 Cylindrical surface 662 Tapered surface 7 Retaining ring

Claims (1)

Lower column,
An upper column fitted to the lower column so as to be relatively slidable in the axial direction;
A female steering shaft rotatably supported by the upper column by a rolling bearing provided on the upper side of the upper column and having a steering wheel mounted on the rear side of the vehicle body;
A rolling bearing provided on the lower side of the lower column is rotatably supported by the lower column and engaged with the female steering shaft so as to be relatively movable in the axial direction and capable of transmitting rotational torque. A male steering shaft for transmitting the rotation of the steering wheel to the wheel,
A hollow cylindrical bush inserted between the inner peripheral surface of the lower column and the outer peripheral surface of the female steering shaft, and formed with an axial slit,
An elastic member that is inserted between the outer peripheral surface of the bush and the inner peripheral surface of the lower column, biases the bush in the direction of reducing the diameter, and presses the inner peripheral surface of the bush against the outer peripheral surface of the female steering shaft; A steering apparatus characterized by comprising:

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