JP5471354B2 - Steering device - Google Patents

Description

  The present invention relates to a steering device installed in a vehicle.

A steering device that can adjust the position of a steering wheel attached to a steering shaft is used so that the driver can drive in a preferable posture. As such a device, for example, there is a device disclosed in Patent Document 1, and this steering device moves the column tube that rotatably supports the steering shaft in the vertical direction, thereby electrically moving the steering wheel. An electric tilt adjustment mechanism for adjusting the position is provided.
FIG. 6 is a cross-sectional view of a steering apparatus provided with a conventional electric tilt adjustment mechanism. This steering device includes a fixing bracket 90 fixed to a fixing member 99 on the vehicle body side, a tilt screw 91 attached to the fixing bracket 90 so as to be rotatable, and a tilt nut that moves up and down by the rotation of the tilt screw 91. 92 and a motor (not shown) for rotating the tilt screw 91 is provided.

  In this steering apparatus, a guide bracket 98 is attached to the column tube 93, and a tilt nut 92 is attached to the guide bracket 98. When the tilt screw 91 is rotated by the motor, the tilt nut 92 moves up and down along the tilt screw 91 together with the guide bracket 98 and the column tube 93. By this movement, the steering shaft 94 supported by the column tube 93 and the steering wheel (not shown) fixed to the upper end thereof can be adjusted to desired positions in the vertical direction.

  Further, in this electric tilt adjusting mechanism, a straight hole 92A is formed in a part of the peripheral wall of the tilt nut 92 in order to prevent the generation of noise due to rattling between the tilt nut 92 and the tilt screw 91. In addition, a screw hole 92B is formed, and a holding member 97, a compression spring 96, and a set bolt 95 are provided in these holes 92A and 92B. The set bolt 95 is a member that is screwed into the screw hole 92 </ b> B and stops the compression spring 96. The holding member 97 is pushed toward the tilt screw 91 by the compression spring 96 and is in contact with the outer peripheral surface of the tilt screw 91. . When the pressing member 97 is pressed to the tilt screw 91 side, rattling between the tilt nut 92 and the tilt screw 91 is prevented. In FIG. 6, a gap g is provided between the outer peripheral surface of the column tube 93 and the tilt nut 92 in order to press the tilt nut 92 against the tilt screw 91.

JP 2009-61927 A (see FIG. 4)

According to the configuration of FIG. 6, rattling between the tilt nut 92 and the tilt screw 91 can be prevented. For this purpose, it is necessary to form the hole 92 </ b> A and the screw hole 92 </ b> B in the tilt nut 92. In addition, it is necessary to attach three small parts (pressing member 97, compression spring 96 and set bolt 95) to these holes 92A and screw holes 92B. As described above, the tilt nut 92 is subjected to various processing (hole processing), and many small parts are incorporated. Therefore, labor is required for manufacturing, which causes an increase in cost.
In addition, since the hole 92A and the screw hole 92B penetrating the peripheral wall of the tilt nut 92 are formed, and the strength and durability of the tilt nut 92 are thereby reduced, the tilt adjustment function inherent to the tilt nut 92 is exhibited. In order to achieve this, it is necessary to increase the meshing length with the tilt screw 91, and as a result, the tilt nut 92 may be increased in size.

  Therefore, the present invention prevents rattling even if the nut member (tilt nut) is not drilled as in the prior art and the nut member (tilt nut) does not incorporate many small parts. An object of the present invention is to provide a steering device capable of

The steering device according to the present invention is located next to the column tube, a column tube that rotatably supports the steering shaft, a fixing bracket for attaching the column tube to a fixing member on the vehicle body side so as to be adjustable. And a screw shaft that is attached to the fixed bracket with the axial direction directed in the direction of the position adjustment, and that is rotated by a motor, is provided so as to be able to move integrally with the column tube, and is screwed to the screw shaft to be connected to the screw shaft. A nut member that moves along the screw shaft by rotation, a nut outer surface that faces the column tube in the outer peripheral surface of the nut member, and a tube that faces the nut outer surface in the outer peripheral surface of the column tube It provided only between the outer surface, in one direction towards the said nut outer surface from said tube outer surface And an elastic member which presses the nut member to the screw shaft, between the elastic member and the tube outer surface, a sliding member having a frictional resistance smaller frictional resistance than of the elastic member with respect to the tube outer side surface It is characterized by interposition .

According to the present invention, since the nut member is pressed against the screw shaft by the elastic member, rattling between the nut member and the screw shaft is prevented. And in order to prevent such rattling, an elastic member may be provided between the nut member and the column tube, and there is no need to perform various processing on the nut member as in the prior art. It is not necessary to incorporate small parts into the nut member.
Further, when the elastic member provided between the nut member and the column tube presses the nut member against the screw shaft, as a reaction force, the elastic member presses the column tube. When trying to move in the longitudinal direction, a frictional force is generated between the elastic member and the column tube.
Therefore, according to the present invention, a sliding member having a friction resistance smaller than the friction resistance of the elastic member with respect to the tube outer surface is interposed between the elastic member and the tube outer surface of the column tube. Therefore, the frictional force can be reduced and the movement of the column tube can be prevented from being hindered.

Further, when the direction in which the column tube moves by driving the motor is a tilt direction, the length of the sliding member in the tilt direction is preferably the same as the length of the elastic member in the tilt direction. .

  According to the present invention, rattling between the nut member and the screw shaft can be prevented without drilling holes in the nut member as in the past or without incorporating many small parts into the nut member. Therefore, the manufacturing cost of the steering device can be reduced.

It is the schematic diagram which looked at the steering device of the present invention from the side. It is a cross-sectional view of a portion provided with a tilt adjustment mechanism. It is sectional drawing of an elastic member and its circumference | surroundings. It is a cross-sectional view of a portion provided with a tilt adjustment mechanism portion of the steering device (second embodiment) of the present invention. It is sectional drawing which shows the modification of 1st embodiment (FIG. 3). It is a cross-sectional view of a conventional steering device.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic view of the steering device of the present invention as seen from the side. In the following description, front / rear, up / down, and left / right based on the driver operating the steering device are used as terms indicating directions.
The steering device of the present invention includes a steering column 1 and a fixing bracket that attaches the steering column 1 to a fixing member 9 on the vehicle body side. The fixed bracket includes an upper bracket 2 and a lower bracket 3.

The steering column 1 has a cylindrical column tube 11 that supports the steering shaft 10, and the steering shaft 10 is rotatably supported inside the column tube 11. A steering wheel (steering member) 12 is fixed to the upper end portion of the steering shaft 10 protruding from the upper portion of the column tube 11.
The lower end portion of the steering shaft 10 protruding from the lower portion of the column tube 11 is connected to the input shaft 40 of the steering gear mechanism 4 provided in front of the cab via an intermediate shaft 5 having universal joints at both ends. Is done.

The upper bracket 2 and the lower bracket 3 are for attaching the column tube 11 to the fixing member 9 on the vehicle body side so that the position can be adjusted. The upper bracket 2 supports the middle part of the column tube 11, and the lower bracket 3 is the column tube. The lower part of 11 is supported. With the upper and lower brackets 2 and 3, the column tube 11 is attached to the vehicle-side fixing member 9 in an inclined posture with the lower side directed forward and downward.
When the driver applies a steering torque to the steering wheel 12 for steering, the steering torque is transmitted to the input shaft 40 of the steering gear mechanism 4 via the steering shaft 10 and the intermediate shaft 5, and the steering gear. Wheels (not shown) are steered by the operation of the mechanism 4.

  The steering apparatus of the present invention can change the position of the steering wheel 12 operated by the driver up and down and front and rear in accordance with the driving posture. For this purpose, tilt adjustment for changing the inclination angle of the column tube 11 is possible. The mechanism part and the telescopic adjustment mechanism part which expands and contracts the column tube 11 in the longitudinal direction are provided.

  In order to change the inclination angle of the column tube 11, a support pin 30 extending in the left-right direction is provided on the lower bracket 3, and the lower part of the column tube 11 (steering column 1) rotates to the support pin 30. It is attached freely. Then, on the upper bracket 2 side, the column tube 11 is moved by the rotation of the motor M1 of the tilt adjustment mechanism. This movement includes movement of the vertical component. For this reason, the column tube 11 can be swung up and down around the center line of the support pin 30, and the tilting operation is performed by this swing. A direction in which the column tube 11 moves with a vertical component is called a tilt direction.

FIG. 2 is a cross-sectional view of a portion where the tilt adjustment mechanism is provided. The column tube 11 includes an inner cylinder 21 and an outer cylinder 22 that partially overlaps with the outer side of the inner cylinder 21 in the radial direction. A guide bracket 15 is attached to the outside of the outer cylinder 22 in the range of the upper bracket 2, and the guide bracket 15 includes an annular main body 16 that is fitted on the outer cylinder 22 and left and right from the main body 16. It has the guide parts 17 and 18 extended in the direction.
The main body 16 supports the outer cylinder 22 in a state in which it can move in the direction of the center line C1 of the column tube 11 but cannot move in the direction perpendicular to the center line C1. Note that the main body 16 supports the outer cylinder 22 so as to be movable in the direction of the center line C1 as described above, by swinging the column tube 11 up and down around the center line of the support pin 30 of the lower bracket 3. This is because the column tube 11 (outer cylinder 22) slightly moves in the direction of the center line C1 with respect to the guide bracket 15 on the upper bracket 2 side.

  A guide shaft 19 is attached to the left guide portion 17 of the guide bracket 15, and the guide shaft 19 is guided by a guide hole 2 c having a long hole shape formed in the side wall 2 a on the left side of the upper bracket 2. Yes. Further, as will be described later, a tilt nut 8 is attached to the right guide portion 18, and a part of the tilt nut 8 has a long hole shape formed in the side wall 2 b on the right side of the upper bracket 2. It is guided by a certain guide hole 2d. As a result, the guide bracket 15 is attached to the upper bracket 2 such that it can move in the tilt direction and cannot move in the direction orthogonal to the tilt direction (with limited movement).

  Further, the inner cylinder 21 and the outer cylinder 22 are configured to be relatively movable in the common center line C1 direction. Then, the overlapping length (the overlapping length in the direction of the center line C1) where the inner cylinder 21 and the outer cylinder 22 overlap is increased or decreased by the telescopic adjustment mechanism unit, and the telescopic operation is performed. The telescopic adjustment mechanism will be described later. Also by this telescopic operation, the column tube 11 (outer cylinder 22) moves in the direction of the center line C1 with respect to the guide bracket 15.

The steering device according to the present invention is a tilt adjusting mechanism that is attached to the upper bracket 2 and is rotated by driving a motor M1 (see FIG. 1), and a linear tilt screw (screw shaft) 7 is screwed into the tilt screw 7. The tilt nut (nut member) 8 is provided. The motor M1 is attached to the upper bracket 2.
The tilt screw 7 is located on the right side of the column tube 11 (may be on the left side), and the axial direction (center line C2 direction) is in the tilt direction that is the direction of position adjustment of the column tube 11. Attached to the upper bracket 2. The tilt screw 7 is attached to the upper bracket 2 so that the tilt screw 7 is rotatable by being supported by rolling bearings 27a and 27b. A worm wheel 13 fixed to the lower end of the tilt screw 7 meshes with a worm 14 (see FIG. 1) that is rotated by the motor M1.

The tilt nut 8 has an annular shape in which a screw hole 8 a that is screwed into the screw portion 7 a of the tilt screw 7 is formed. The tilt nut 8 is fixed to the guide bracket 15. For this reason, when the tilt screw 7 is rotated by the motor M1, the tilt nut 8 moves along the tilt screw 7, that is, in the tilt direction.
Further, since the tilt nut 8 is fixed to the guide bracket 15, the column tube 11 and the tilt nut 8 supported by the guide bracket 15 are provided so as to be integrally movable in the tilt direction. Become.

  In the steering device of the present invention, the elastic member 23 is provided between the tilt nut 8 and the outer tube 22 of the column tube 11. FIG. 3 is a cross-sectional view of the elastic member 23 and its surroundings. In the present embodiment, the elastic member 23 is made of rubber, and in a compressed state, a part 26 of the outer peripheral surface of the tilt nut 8 and a part of the outer peripheral surface of the outer cylinder 22 that faces the part 26. It is provided between the unit 27. Further, in the present embodiment, a sliding member 24 is interposed between a part 27 of the outer peripheral surface of the outer cylinder 22 and the elastic member 23.

  The elastic member 23 is provided in a compressed state in a direction connecting a part 26 of the outer peripheral surface of the tilt nut 8 and a part 27 of the outer peripheral surface of the outer cylinder 22. For this reason, the elastic member 23 is in a state where the tilt nut 8 is pressed against the tilt screw 7 by its elastic restoring force, and the pressing direction is the right direction (arrow X1 in FIG. 3) perpendicular to the center line C2 of the tilt screw 7. Direction). In this way, the elastic member 23 presses the screw hole 8a of the tilt nut 8 against the screw portion 7a of the tilt screw 7, so that rattling between the tilt nut 8 and the tilt screw 7 is prevented. It is possible to suppress the generation of abnormal noise due to the attachment.

The first contact surface 23 a that contacts the part 26 of the outer peripheral surface of the tilt nut 8 of the elastic member 23 has a shape along the part 26 and is in contact with the part 26 on the surface. Yes. When the part 26 of the tilt nut 8 has, for example, a curved surface shape (arc shape) centered on the center line C2, the contact surface 23a of the elastic member 23 also has a curved surface shape (arc shape) centered on the center line C2. ).
Furthermore, the elastic member 23 of the present embodiment has a length L1 in the tilt direction set to be the same as a length L2 in the tilt direction of the tilt nut 8, and the elastic member 23 pushes the tilt nut 8 in a wide range. be able to.

  As described above, when the tilt nut 8 is pressed against the tilt screw 7 by the elastic member 23 provided between the tilt nut 8 and the outer cylinder 22, the elastic member 23 causes the outer cylinder 22 to move as a reaction force. It will be pushed in the left direction (arrow X2). In this state, when the column tube 11 is swung in the vertical direction and the outer cylinder 22 tries to move in the direction of the center line C1 (see FIG. 2) with respect to the guide bracket 15, the elastic member 23 and the outer A frictional force is generated between the cylinder 22. Therefore, in the present embodiment, the frictional force is reduced by providing the sliding member 24 between the part 27 of the outer peripheral surface of the outer cylinder 22 and the elastic member 23.

  For this reason, the sliding member 24 has a friction resistance smaller than the friction resistance of the elastic member 23 with respect to a part 27 of the outer peripheral surface of the outer cylinder 22, and can be made of, for example, a resin. The friction coefficient (static friction coefficient and dynamic friction coefficient) is smaller than 23. According to the sliding member 24, the sliding resistance with respect to the part 27 can be made smaller than when the elastic member 23 directly contacts the part 27 of the outer peripheral surface of the outer cylinder 22. Therefore, when the outer cylinder 22 tries to move in the direction of the center line C2 with respect to the guide bracket 15 (when it moves), a frictional force is generated between the outer cylinder 22 and the frictional force can be reduced. It is possible to prevent the movement of the outer cylinder 22 from being hindered.

The first contact surface 24 a that contacts the part 27 of the outer peripheral surface of the outer cylinder 22 of the sliding member 24 has a shape along the part 27 and is in contact with the part 27 on the surface. . Since the outer peripheral surface of the outer cylinder 22 has a curved surface shape (arc shape) centered on the center line C1 (see FIG. 2), the contact surface 24a of the sliding member 24 also has a curved surface shape centered on the center line C1. (Arc shape).
Further, the sliding member 24 of the present embodiment has a length L3 in the tilt direction set to be the same as the length L1 of the elastic member 23 in the tilt direction. Further, the second contact surface 23b opposite to the first contact surface 23a of the elastic member 23 and the second contact surface 24b opposite to the first contact surface 24a of the sliding member 24 are the same. The shape (contour shape).
For this reason, the elastic member 23 pushes the sliding member 24 over a wide range, and the sliding member 24 comes into contact with the outer cylinder 22 over a wide range. For this reason, even if the pressing force of the tilt nut 8 in the X1 direction by the elastic member 23 is large, the force in the X2 direction in which the sliding member 24 presses the outer cylinder 22 caused by the reaction force is dispersed to reduce the surface pressure. It is possible to suppress an increase in sliding resistance between the sliding member 24 and the outer cylinder 22.

  Further, although the elastic member 23 and the sliding member 24 are sandwiched between the tilt nut 8 and the outer cylinder 22, the elastic member 23 may not be fixed to the tilt nut 8, and the sliding The moving member 24 may not be fixed to the elastic member 23. In order to attach the tilt nut 8 to the guide bracket 15, an attachment hole 25 is formed in the guide bracket 15 (see FIG. 3), and the elastic member 23 and the sliding member 24 are separated by a small gap by the attachment hole 25. This is because the elastic member 23 and the sliding member 24 are not dropped from the installation position.

  The telescopic adjustment mechanism will be described. In FIG. 2, the telescopic adjustment mechanism portion includes a telescopic screw 57 that is rotated by a telescopic operation motor (not shown), and a telescopic nut 58 that is screwed to the telescopic screw 57. The telescopic screw 57 has a center line arranged in a direction parallel to the center line C <b> 1 of the column tube 11, and is attached to one of the inner cylinder 21 and the outer cylinder 22. On the other hand, the telescopic nut 58 is attached to the other of the inner cylinder 21 and the outer cylinder 22. As the telescopic screw 57 rotates, the inner cylinder 21 and the outer cylinder 22 move in the direction of the center line C1, and a telescopic operation is performed.

FIG. 4 is a cross-sectional view of a portion of the steering device (second embodiment) according to the present invention where a tilt adjusting mechanism is provided.
In the second embodiment, the elastic member 23 is provided between the inner cylinder 21 included in the column tube 11 and the tilt nut 8. The elastic member 23 presses the tilt nut 8 against the tilt screw 7 as in the first embodiment.

Since the elastic member 23 is provided between the inner cylinder 21 and the tilt nut 8, a hole 35 (or notch) is formed in a portion of the outer cylinder 22 where the elastic member 23 is provided, The elastic member 23 (and a part on the left side of the tilt nut 8) passes through this portion.
When the telescopic adjustment is performed, the outer cylinder 22 moves in the direction of the center line C1, while the inner cylinder 21 does not move in the direction of the center line C1 and is in a fixed state. It is also possible to eliminate the sliding member 24 provided. Other configurations are the same as those in the first embodiment.

  As described above, according to each of the embodiments described above, the steering device includes the tilt adjustment mechanism having the motor M1 and the like in order to adjust the position of the steering wheel 12 (see FIG. 1) electrically in the vertical direction. In such a tilt adjusting mechanism, in order to prevent rattling between the tilt nut 8 and the tilt screw 7, the tilt nut 8 and the column tube 11 (the outer cylinder 22) are used as shown in FIG. Alternatively, it is only necessary to provide the elastic member 23 between the inner cylinder 21), and there is no need to perform various hole processing other than the tilt adjustment function on the tilt nut 92 as shown in the conventional example of FIG. In addition, it is not necessary to incorporate small parts into the tilt nut 92. For this reason, the manufacture of the steering device is simplified, the number of parts can be reduced, and the manufacturing cost can be reduced.

  Further, the elastic member 23 may be provided in a space inside (center side) the tilt nut 8 that has already been formed, that is, in a space between the tilt nut 8 and the column tube 11. It is not necessary to provide a new space for this. For this reason, it is not necessary to increase the size of the steering device.

In the conventional example shown in FIG. 6, since the size of the tilt nut 92 is limited to some extent, the size of the compression spring 96 incorporated therein is also limited. For this reason, it is difficult to increase the pressing force by the pressing member 97, and the setting range of the pressing force is limited.
However, according to each of the embodiments of the present invention, it is easy to change the size of the elastic member 23, and it is easy to set a wide range from a large pressing force to a small pressing force. Furthermore, adjustment of the pressing force is facilitated by changing the material of the elastic member 23 and changing the compression allowance (that is, the thickness of the elastic member 23 in the natural state).

  Further, in each of the embodiments, the tilt nut 8 is screwed to the tilt screw 7 attached to the upper bracket 2 so that they are mechanically connected. The tilt nut 8 and the column tube 11 are connected to each other. Since the elastic member 23 (and the sliding member 24) is interposed between the column tube 11 and the column tube 11 is pressed from the left-right direction, the upper bracket 2 includes the column tube 11 in the left-right direction. Stiffness can be increased. For this reason, it becomes possible to reduce the member (for example, spring member) for improving the attachment rigidity of the column tube 11 conventionally required.

  The steering apparatus of the present invention can be applied to an electric power steering apparatus and a hydraulic power steering apparatus, and the steering apparatus of the present invention is not limited to the form shown in the drawings, and may be of other forms within the scope of the present invention. May be. For example, the elastic member 23 may be other than rubber, and for example, may be configured using a metal compression spring (disc spring).

FIG. 5 is a sectional view showing a modification of the first embodiment (FIG. 3). In the first embodiment (FIG. 3), the contact surface 24 a of the sliding member 24 that contacts the part 27 of the outer peripheral surface of the outer cylinder 22 has a shape along the part 27, and the center line of the column tube 11. It is a curved surface shape (arc shape) centered on C1.
However, in the case of FIG. 5, a part 27 of the outer peripheral surface of the outer cylinder 22 with which the sliding member 24 contacts is a flat surface. The contact surface 24a of the sliding member 24 that contacts the part 27 is also a flat surface. These planes are surfaces orthogonal to the direction (arrow X2) in which the sliding member 24 is pushed by the part 27 of the outer cylinder 22 by the elastic member 23.

  Further, in the case of the second embodiment (FIG. 4), the sliding member 24 is omitted, and the elastic member 23 is in direct contact with the inner cylinder 21. Similarly, a part of the outer peripheral surface of the inner cylinder 21 that contacts the sliding member 24 may be a flat surface, and the contact surface of the elastic member 23 that contacts a part of the outer peripheral surface of the inner cylinder 21 is also a flat surface. Good.

  The embodiments disclosed this time are examples of the present invention and are not restrictive. The scope of the present invention is defined by the terms of the claims, and includes the meanings equivalent to the configurations of the claims and all modifications within the scope.

  2: upper bracket (fixed bracket), 7: tilt screw (screw shaft), 8: tilt nut (nut member), 9 fixed member, 10: steering shaft, 11: column tube, 23: elastic member, 24: sliding Member, M1: Motor

Claims (2)

A column tube that rotatably supports the steering shaft;
A fixing bracket for attaching the column tube to the fixing member on the vehicle body side so that the position can be adjusted;
A screw shaft that is located next to the column tube and is attached to the fixed bracket with the axial direction facing the direction of the position adjustment, and is rotated by a motor;
A nut member which is provided so as to be movable together with the column tube and which is screwed into the screw shaft and moves along the screw shaft by rotation of the screw shaft;
Only provided between the tube outer surface facing the nut outer surface of the outer peripheral surface of the column tube facing the nut outer surface and said column tube of the outer peripheral surface of the nut member, said tube outer surface An elastic member that presses the nut member against the screw shaft in one direction from the nut to the outer surface of the nut ,
A steering apparatus , wherein a sliding member having a friction resistance smaller than a friction resistance of the elastic member with respect to the tube outer surface is interposed between the elastic member and the tube outer surface. The length in the tilt direction of the sliding member is the same as the length in the tilt direction of the elastic member when the direction in which the column tube moves by driving the motor is a tilt direction. Steering device.

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