JP2006264639A - Transmission ratio variable steering device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transmission ratio variable steering device for a vehicle not increasing the number of parts and mounting man-hours while realizing miniaturization of the transmission ratio variable steering device for the vehicle without mounting a spiral case to a hole cover 5 by a fixing string 6 or the like. <P>SOLUTION: The transmission ratio variable steering device for the vehicle is provided with a transmission ratio variable steering actuator 3 for the vehicle; a spiral cable unit 4 having a spiral cable; and the hole cover 5 for storing the transmission ratio variable steering actuator 3 for the vehicle and the spiral cable unit 4. Further, an outer cover 41 of the spiral cable unit 4 has, for example, a non-circular part 41a such as a projection part formed radially to a projection shape. Further, the hole cover 5 has an engagement part 51 engaged with an outer periphery of the non-circular part 41a. Thereby, the hole cover 5 can restrict the outer cover 41 in a rotation direction. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a vehicular transmission ratio variable steering apparatus that is used in a vehicle and can change a transmission ratio between a steering angle and a turning angle.

  The vehicle transmission ratio variable steering apparatus includes a vehicle transmission ratio variable steering actuator such as a motor. When the vehicular transmission ratio variable steering device is mounted on the steering column of the vehicle, the vehicular transmission ratio variable steering actuator itself rotates relative to the vehicle body. As described above, when the vehicle transmission ratio variable steering actuator rotates with respect to the vehicle body, a spiral cable is provided that enables current to be supplied to the vehicle transmission ratio variable steering actuator (see, for example, Patent Document 1). .

Here, a conventional transmission ratio variable steering apparatus for a vehicle will be briefly described with reference to FIG. FIG. 3A shows an axial sectional view of a conventional vehicle transmission ratio variable steering device, and FIG. 3B shows a right side view of FIG. As shown in FIGS. 3A and 3B, the vehicle transmission ratio variable steering actuator 3 and the spiral cable unit 4 constituting the vehicle transmission ratio variable steering apparatus are fixed to the vehicle body for waterproofing and soundproofing. The hole cover 5 is housed. However, the vehicle transmission ratio variable steering actuator 3 and the spiral cable unit 4 are arranged so as to allow slight movement in the axial direction (for example, the motor axial direction) and the radial direction with respect to the hole cover 5. Therefore, in the conventional vehicle transmission ratio variable steering apparatus, the spiral case of the spiral cable unit 4 is attached to the hole cover 5 by, for example, the fixed string 6. Thus, the spiral case is fixed to the hole cover 5 while allowing slight movement in the axial direction and the radial direction.
JP 2004-336867 A

  However, in order to secure a space for the fixed string 6 for attaching the spiral case of the spiral cable unit 4 to the hole cover 5, a large space is required on the outer peripheral side of the spiral case. As a result, the radial direction of the hole cover 5 and thus the vehicle transmission ratio variable steering device is increased. Furthermore, since the fixing string 6 for attachment is required, the number of parts increases and the number of attachment steps increases.

  The present invention has been made in view of such circumstances, and without reducing the size of the variable transmission ratio steering apparatus for a vehicle without attaching the spiral case to the hole cover 5 with the fixed string 6 or the like, And it aims at providing the transmission ratio variable steering device for vehicles which does not increase an installation man-hour.

Means for Solving the Problems and Effects of the Invention

  The vehicle transmission ratio variable steering apparatus of the present invention includes a vehicle transmission ratio variable steering actuator, a spiral cable unit, and a hole cover. The vehicle transmission ratio variable steering actuator changes the transmission ratio of the turning angle to the steering angle. The spiral cable unit includes a spiral case having a non-circular portion whose outer peripheral shape is a non-circular shape, and a spiral cable housed in the spiral case. Here, one end of the spiral cable is led out from the spiral case, and the other end is fixed to the vehicle transmission ratio variable steering actuator. The hole cover is fixed to the vehicle body and houses the vehicle transmission ratio variable steering actuator and the spiral cable unit. And this hole cover has an engaging part engaged with the outer periphery of the said non-circular part.

  Here, the engaging portion of the hole cover of the vehicle transmission ratio variable steering device of the present invention is engaged with the outer periphery of the non-circular portion of the spiral case of the spiral cable unit. Therefore, the spiral case is regulated in the rotational direction with respect to the hole cover. That is, there is no need for a fixing string for fixing the spiral case to the hole cover as in the prior art. As a result, the number of parts can be reduced. Furthermore, since it is not necessary to attach a fixed string, the mounting property is greatly improved, and the number of mounting steps can be reduced.

  Further, by engaging the engagement portion of the hole cover with the outer periphery of the non-circular portion of the spiral case, there is no large space interposed between the hole cover and the spiral case as in the prior art. As a result, it is possible to reduce the size of the hole cover in the radial direction, and thus the size of the vehicle transmission ratio variable steering device in the radial direction. In addition, a slight movement in the radial direction of the spiral case with respect to the hole cover can be sufficiently allowed by interposing a slight gap between the engaging portion of the hole cover and the non-circular portion of the spiral case. Thus, even if a slight gap is interposed between the engaging portion and the non-circular portion, the size can be significantly reduced as compared with the conventional case.

  Here, the non-circular portion is formed, for example, in a concave shape or a convex shape in the radial direction. By making the non-circular portion concave or convex in the radial direction, the outer periphery of the non-circular portion can be reliably engaged with the engaging portion of the hole cover. That is, the rotation of the spiral case with respect to the hole cover can be reliably restricted.

  The non-circular portion has a harness pull-out convex portion formed in a radial convex shape, and the spiral cable unit extends from the harness pull-out convex portion to the outside of the spiral case, and has one end A spiral cable harness that connects the side to the spiral cable may be provided. That is, the harness lead-out convex portion is used for the convex portion of the non-circular portion of the spiral case. Here, the spiral case usually has a harness drawing projection for extending the spiral cable harness to the outside. In this way, by using the normally provided harness pull-out convex portion as the convex portion of the non-circular portion, there is no need to newly form a non-circular portion that engages with the engaging portion of the hole cover.

  The engaging portion may elastically support the outer peripheral surface of the non-circular portion. That is, by elastically supporting the spiral case by the engaging portion, it is possible to reliably allow slight movement of the spiral case in the radial direction and the axial direction with respect to the hole cover.

  The engaging portion that elastically supports the outer peripheral surface of the non-circular portion has, for example, an annular shape that protrudes toward the inner peripheral side and contacts the outer peripheral surface of the non-circular portion, and has an inner peripheral lip that is deformable in the radial direction It is good to do. Since the engaging portion has an annular inner peripheral lip that can be deformed in the radial direction, it is possible to reliably allow slight movement of the spiral case relative to the hole cover in the radial direction and the axial direction. Furthermore, since the inner peripheral lip can be deformed in the radial direction, the inner peripheral side of the inner peripheral lip can always be brought into contact with the outer peripheral surface of the spiral case. Therefore, good sealing performance can be obtained by the inner peripheral lip. The inner peripheral lip is made of, for example, rubber or resin. In particular, when the inner lip is made of rubber, it can be more reliably deformed in the radial direction, and good sealing properties can be obtained.

  The hole cover further includes a vehicle body fixing portion fixed to the vehicle body, and a deformable portion that is interposed between the vehicle body fixing portion and the engaging portion and is deformable in a radial direction and an axial direction. Also good. The deformation part can sufficiently allow the spiral case to move in the radial direction and the axial direction with respect to the vehicle body fixing part. The deforming portion is made of, for example, rubber or resin. Moreover, you may make it a deformation | transformation part consist of bellows shapes, for example. In addition, it is better that the hole cover includes a deforming portion and an engaging portion having an inner peripheral lip. Thereby, the movement to the radial direction and axial direction of the spiral case with respect to a vehicle body fixing | fixed part can be permitted more fully.

  Next, the present invention will be described in more detail with reference to embodiments. A vehicle transmission ratio variable steering device (hereinafter simply referred to as a “steering device”) in the present embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 is an axial sectional view of the steering device. FIG. 2 is a right side view of FIG. Here, in the following description, the axial direction means the rotational axis direction of the motor constituting the steering device. The radial direction means a direction orthogonal to the axial direction. The circumferential direction means the rotation direction of the rotating shaft.

  The steering device is a device that is mounted on a steering column (not shown) of a vehicle and can change a transmission ratio of a turning angle of a steered wheel (not shown) to a steering angle of a steering wheel (not shown). is there. As shown in FIGS. 1 and 2, the steering device includes an input shaft 1, an output shaft 2, a vehicle transmission ratio variable steering actuator (hereinafter simply referred to as “actuator”) 3, a spiral cable unit 4, And a hole cover 5.

  The input shaft 1 is connected to the steering wheel. The input shaft 1 is a shaft that transmits the steering angle of the steering wheel by the driver. The output shaft 2 has a pinion gear (not shown) formed on one end side. This pinion gear meshes with a rack gear (not shown) whose both ends are connected to the steered wheels. That is, the rotation of the output shaft 2 is converted into the axial movement of the rack gear, and the steered wheels are steered.

  The actuator 3 includes a substantially cylindrical housing, and a motor and a speed reducer housed in the housing. The right end side of the actuator 3 in FIG. 1 is coaxially connected to the input shaft 1. Further, the left end side of the actuator 3 in FIG. 1 is coaxially connected to the output shaft 2. The actuator 3 outputs the input rotation (steering angle) of the input shaft 1 to the output shaft 2 and outputs the rotation by driving the motor to the output shaft 2. That is, the actuator 3 outputs to the output shaft 2 a rotation obtained by adding the rotation by driving the motor to the rotation of the input shaft 1. Thus, the actuator 3 can change the transmission ratio of the rotation angle of the output shaft 2 (corresponding to the steering angle) to the rotation angle of the input shaft 1 (corresponding to the steering angle). The actuator 3 is supported so as to be rotatable with respect to the vehicle body.

  The spiral cable unit 4 is disposed on the steering wheel side of the actuator 3. The spiral cable unit 4 is a device for supplying a current to the motor of the actuator 3. In other words, even when the actuator 3 is rotating with respect to the vehicle body, the current can be supplied to the motor of the actuator 3 from a power source fixed on the vehicle body side. The spiral cable unit 4 includes an outer case 41, an inner case (not shown), a spiral cable (not shown), and a spiral cable harness (hereinafter simply referred to as “harness”) 42.

  The outer case (spiral case in the present invention) 41 is made of resin and has a bottomed cylindrical shape with a circular hole formed in the center. The outer case 41 is on the steering wheel side of the actuator 3, and is disposed on the outer peripheral side of the input shaft 1 (portion indicated by a wavy line in FIG. 1) so as to be rotatable relative to the actuator 3 and the input shaft 1. . Therefore, the input shaft 1 is rotatably inserted in the central circular hole. Furthermore, as shown in FIG. 2, the outer case 41 is formed with a harness lead-out convex portion 41a protruding in the radial direction.

  The inner case is made of resin and has a substantially cylindrical shape. The inner case is disposed inside the outer case 41 so as to be relatively rotatable. Further, the inner case is fixed to the housing of the actuator 3. That is, the inner case rotates integrally with the housing of the actuator 3.

  The spiral cable is housed in a spiral between the outer case 41 and the inner case. The inner peripheral end side of the spiral cable is fixed to the inner case and is electrically connected to the motor of the actuator 3. On the other hand, the outer peripheral end side of the spiral cable is fixed to the outer case 41 and led out from the harness lead-out convex portion 41 a of the outer case 41.

  The harness 42 is a cable for supplying current from the power source to the spiral cable. The harness 42 extends from the harness lead-out convex portion 41 a of the outer case 41 to the outside of the outer case 41. The inner end of the harness 42 is fixed to and electrically connected to the outer peripheral end of the spiral cable in the vicinity of the harness lead-out convex portion 41a. Furthermore, the outer end of the harness 42 is fixed to the vehicle body and is electrically connected to a power source (not shown).

  The hole cover 5 is made of rubber such as EPDM and has a substantially cylindrical shape. The hole cover 5 is fixed to the vehicle body and houses the actuator 3 and the spiral cable unit 4 therein. The hole cover 5 includes an engagement portion 51, a vehicle body fixing portion 52, and a bellows portion (deformation portion) 53.

  The engaging portion 51 has a substantially cylindrical shape with a substantially constant wall thickness. The engaging portion 51 accommodates the spiral cable unit 4 on the inner peripheral side. And the engaging part 51 has comprised the shape which followed the outer peripheral shape of the outer side case 41, as shown in FIG. That is, a concave portion 51 a that is concave in the radial direction is formed on the inner peripheral surface of the engaging portion 51. That is, the recess 51a has a shape corresponding to the harness pull-out protrusion 41a. Accordingly, the concave portion 51a of the engaging portion 51 and the harness lead-out convex portion 41a of the outer case 41 are engaged in the circumferential direction. Since the engaging portion 51 is hardly rotated with respect to the vehicle body, the engaging portion 51 restricts the outer case 41 from rotating.

  Furthermore, a harness insertion hole 51 b through which the harness 42 is inserted is formed in the engaging portion 51. Furthermore, the inner peripheral surface of the engaging portion 51 has three annular inner peripheral lips 51 c that protrude toward the inner peripheral side and abut against the outer peripheral surface of the outer case 41. The inner lip 51c can be expanded and contracted in the radial direction. That is, the inner peripheral lip 51c elastically supports the outer peripheral surface of the outer case 41. Thus, when the inner peripheral lip 51c expands and contracts in the radial direction, the outer case 41 tends to rotate relative to the engaging portion 51 when the core of the outer case 41 is displaced from the engaging portion 51. Even in this case, it can be absorbed sufficiently. Furthermore, since the inner peripheral side of the inner peripheral lip 51c is always in contact with the outer peripheral surface of the outer case 41, the outside of the hole cover 5 and the inside of the hole cover 5 can be reliably partitioned. That is, entry of water or dust into the hole cover 5 can be prevented.

  The vehicle body fixing portion 52 has a bottomed cylindrical shape with a circular hole formed in the center. The cylinder portion of the vehicle body fixing portion 52 is fixed to, for example, a cockpit panel (not shown) of the vehicle body. And the cylinder part of the vehicle body fixing | fixed part 52 mainly accommodates the actuator 3 in the inner peripheral side. As shown in FIG. 2, the cylinder portion of the vehicle body fixing portion 52 has a shape that follows the outer peripheral surface of the engaging portion 51 while forming a gap with the outer peripheral surface of the engaging portion 51. That is, the outer peripheral surface of the cylindrical portion of the vehicle body fixing portion 52 is formed with a convex portion 52a that is convex in the radial direction. Further, a part of the cylinder portion of the vehicle body fixing portion 52 on the right end side in FIG. 1 overlaps with a part of the engagement portion 51 on the left end side in FIG. 1 with a slight gap in the axial direction.

  Furthermore, the bottom part 52b on the left side of FIG. 1 of the vehicle body fixing part 52 has a bellows shape that can expand and contract in the radial direction and the axial direction. A circular hole formed in the bottom portion 52b is rotatably fitted on the outer peripheral side of the output shaft 2.

  The bellows portion 53 integrally connects the left end side in FIG. 1 of the engaging portion 51 and the right end side of the vehicle body fixing portion 52. And the bellows part 53 can be expanded and contracted in the axial direction and the radial direction. Further, the thickness of the bellows portion 53 is made thinner than the thickness of the engaging portion 51 and the vehicle body fixing portion 52. This is because the bellows portion 53 can be easily deformed in the axial direction and the radial direction. Therefore, the bellows portion 53 can easily move the engaging portion 51 in the axial direction and the radial direction with respect to the vehicle body fixing portion 52. That is, even when the spiral cable unit 4 moves in the axial direction and the radial direction with respect to the vehicle body fixing portion 52 of the hole cover 5, the bellows portion 53 is deformed in the axial direction and the radial direction so that sufficient absorption is achieved. can do.

  By configuring the vehicle transmission ratio variable steering device as described above, it is possible to reduce the size of the hole cover 5 and thus the vehicle transmission ratio variable steering device as a whole. Furthermore, in order to restrict the rotation of the outer case 41 with respect to the hole cover 5, for example, it is not necessary to use another part such as a fixed string, so that the number of parts can be reduced. Furthermore, the variable transmission ratio steering apparatus for a vehicle according to the present embodiment only has the spiral cable unit 4 inserted into the hole cover 5, so that the mountability is good. Further, the spiral cable unit 4 slightly moves in the axial direction and the radial direction with respect to the vehicle body due to the radial deformation of the inner peripheral lip 51c and the axial and radial deformations of the bellows portion 53. Can also be reliably absorbed.

  In the above embodiment, the rotation of the outer case 41 relative to the engaging portion 51 is restricted by engaging the harness drawing convex portion 41a of the outer case 41 and the concave portion 51a of the engaging portion 51 in the circumferential direction. However, it is not limited to this. A convex or concave portion in the radial direction may be formed on the outer peripheral surface of the outer case 41, and the convex or concave portion may be engaged with the engaging portion 51. Furthermore, the shape of the outer peripheral surface of the outer case 41 may be a non-circular shape as long as it is not a convex shape or a concave shape in the radial direction. Of course, in these cases, the inner peripheral surface of the engaging portion 51 needs to have a shape that follows the shape of the outer peripheral surface of the outer case 41.

It is an axial sectional view of a transmission ratio variable steering device for a vehicle. It is a right view of FIG. It is a figure which shows the conventional transmission ratio variable steering apparatus for vehicles.

Explanation of symbols

1: Input shaft, 2: Output shaft, 3: Transmission ratio variable steering actuator for vehicle, 4: Spiral cable unit, 5: Hole cover, 6: Fixed string, 41: Outer case (spiral case), 41a: For harness extraction Convex part 42: Spiral cable harness 51: Engaging part 51a: Concave part 51b: Harness insertion hole 52: Car body fixing part 52a: Convex part 52b: Bottom part 51c: Inner lip 53: Bellow part (Deformation part)

Claims (6)

A vehicle transmission ratio variable steering actuator for changing the transmission ratio of the steering angle to the steering angle;
A spiral case having a non-circular portion whose outer peripheral shape is a non-circular shape, and a spiral that is housed in the spiral case, one end side is led out from the spiral case, and the other end side is fixed to the vehicle transmission ratio variable steering actuator. A spiral cable unit comprising a cable,
A hole cover that is fixed to a vehicle body and houses the vehicle transmission ratio variable steering actuator and the spiral cable unit;
With
The vehicle transmission ratio variable steering apparatus, wherein the hole cover has an engaging portion that engages with an outer periphery of the non-circular portion.   The vehicle transmission ratio variable steering device according to claim 1, wherein the non-circular portion is formed in a concave shape or a convex shape in a radial direction. The non-circular portion has a harness drawing convex portion formed in a convex shape in the radial direction,
3. The vehicle transmission ratio variable steering device according to claim 2, wherein the spiral cable unit includes a spiral cable harness that extends from the harness drawing convex portion to the outside of the spiral case and connects one end side to the spiral cable.   The vehicular transmission ratio variable steering apparatus according to claim 1, wherein the engaging portion elastically supports an outer peripheral surface of the non-circular portion.   The vehicular transmission ratio variable steering apparatus according to claim 4, wherein the engaging portion has an inner peripheral lip that protrudes inward and contacts the outer peripheral surface of the non-circular portion and is deformable in a radial direction.   The said hole cover further has a vehicle body fixing | fixed part fixed to a vehicle body, and a deformation | transformation part which is interposed between the said vehicle body fixing | fixed part and the said engaging part, and can deform | transform into radial direction and an axial direction. The vehicle transmission ratio variable steering device according to claim 5.

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