Steering device

Abstract

A steering device (100) comprises a first shaft (110) for holding an operating member (200), a second shaft (120), a first tube (130) that moves integrally with the first shaft, a second tube (140) for guiding the first tube (130), a movement mechanism (150) for moving the first tube (140) to a first region in which the first shaft (110) is capable of rotating, and a second region in which the first shaft (110) is not capable of rotating, a locking part (160) disposed farther toward a base end side than the first tube (110) when the first tube (110) is disposed in the first region, and an urging member (170) for urging the locking part (160), wherein the locking part (160) renders the first shaft (110) incapable of rotating by engaging with an engaged portion (112) provided on the first shaft (110), when the first tube (130) is disposed in the second region.

Description

[Technical Field]

[0001] The present invention relates to a steering device for steering a vehicle or the like. [Background technology]

[0002] For example, there is a technology that activates a locking mechanism by contracting an automatically extending and retracting steering column, such as the steering device described in Patent Document 1. When the locking mechanism is activated, the rotation of the shaft to which the steering wheel is attached is locked, making it impossible to rotate the steering wheel. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-298229 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the locking mechanism described in Patent Document 1 has a locking piece that is biased radially inward by a protruding spring. This locking piece is pressed against the outer surface of the movable tube, which moves when the steering wheel position is adjusted to suit the driver's body type. This generates friction between the locking piece and the movable tube, raising concerns about durability and the generation of abnormal noise.

[0005] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a steering device in which the locking piece does not rub against the movable tube in the biasing direction when the position of the steering wheel is being adjusted. [Means for solving the problem]

[0006] In order to achieve the above object, one aspect of the present invention provides a steering device comprising: a first shaft having an axis extending from a base end to a tip end and rotatably holding an operating member around the axis; a second shaft arranged on the base end side of the first shaft and inserted inside the first shaft so as to be rotatable around the axis and movable in the axial direction; a first tube rotatably supporting the first shaft on the inside and moving in the axial direction integrally with the first shaft; a second tube guiding the first tube in the axial direction and rotatably supporting the second shaft on the inside; a moving mechanism that moves the first tube in the axial direction to a first region in which the first shaft can rotate and a second region that is located on the base end side of the first region and in which the first shaft cannot rotate; a locking piece that is movable radially relative to the second tube so as to be arranged on the base end side of the first tube arranged in the first region; and a biasing member that biases the locking piece radially inward relative to the second tube; [Effects of the Invention]

[0007] Even when the moving mechanism moves the first tube in an area where the driver can operate the operating member, the locking piece and the first tube do not rub against each other, so no damage due to friction occurs between the locking piece and the first tube, ensuring the durability of the first tube and creating a structure that suppresses the generation of abnormal noise. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 2 is a perspective view showing the steering device in an extended state. [Figure 2] FIG. 2 is a cross-sectional view of the steering device in an extended state. [Figure 3] FIG. 4 is a perspective view showing the steering device in a contracted state with the second tube omitted. [Figure 4] FIG. 2 is a cross-sectional view of the steering device in a contracted state. [Figure 5]FIG. 10 is a cross-sectional view showing a first modified example of a steering device. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of a steering device according to the present invention will be described with reference to the drawings. Note that the following embodiment is an example for explaining the present invention and is not intended to limit the present invention. For example, the shapes, structures, materials, components, relative positional relationships, connection states, numerical values, mathematical formulas, the content of each step in a method, and the order of each step shown in the following embodiment are examples and may include content not described below. Furthermore, while geometric expressions such as parallel and orthogonal may be used, these expressions do not indicate mathematical precision and include substantially allowable errors, deviations, etc. Furthermore, expressions such as simultaneous and identical also include substantially allowable ranges.

[0010] The drawings are schematic diagrams in which emphasis, omission, or adjustment of proportions is appropriately made for the purpose of explaining the present invention, and differ from the actual shapes, positional relationships, and proportions. The X-axis, Y-axis, and Z-axis shown in the drawings represent Cartesian coordinates arbitrarily set for the purpose of explaining the drawings. In other words, the Z-axis is not necessarily an axis along the vertical direction, and the X-axis and Y-axis are not necessarily located within a horizontal plane.

[0011] In addition, in the following, multiple inventions may be collectively described as one embodiment, and some of the contents described below may be described as optional components related to the present invention.

[0012] FIG. 1 is a perspective view showing the steering device 100 in an extended state. FIG. 2 is a cross-sectional view of the steering device 100 in an extended state. FIG. 3 is a perspective view showing the steering device 100 in a contracted state, with the second tube omitted. FIG. 4 is a cross-sectional view of the steering device 100 in a contracted state. Note that the steering device 100 is used with the first shaft 110 and other components tilted obliquely with respect to the horizontal plane, but the axes of the first shaft 110 and other components will be described as being along the Y axis in the drawings. Also, Y+ corresponds to the front side of the vehicle, and Y- corresponds to the rear side of the vehicle. Also, in the case of this embodiment, the first region and second region shown in FIGS. 2 and 4 indicate the movement regions in the axial direction of the first tube 130 when the end face on the base end side of the first tube 130 is used as a reference.

[0013] The steering device 100 is arranged in front of the driver's seat (not shown) in a vehicle such as a passenger car, and rotatably holds an operating member 200 that is operated by a driver seated in the driver's seat, and is equipped with a first shaft 110, a second shaft 120, a first tube 130, a second tube 140, a moving mechanism 150, a lock piece 160, and a biasing member 170.

[0014] The first shaft 110 is a rod-shaped member also called an upper shaft, and is arranged so that an imaginary axis extends (extends in the Y-axis direction in the figure) from the base end (the end on the Y+ side in the figure) to the tip end (the end on the Y- side in the figure). The first shaft 110 is a member that holds the operating member 200 rotatably around the axis. An insertion hole 111 into which the second shaft 120 is inserted is formed in the first shaft 110 except for the tip end.

[0015] In this embodiment, an engaged portion 112 that engages with a lock piece 160 (described in detail later) is attached to the outer periphery of the base end of the first shaft 110. The engaged portion 112 is a cylindrical member into which the base end of the first shaft 110 is inserted and which is fixed in both the axial and circumferential directions. The outer circumferential surface of the engaged portion 112 is provided with unevenness (not shown) extending in the axial direction, which engages with unevenness (not shown) provided on the end face of the lock piece 160 in the circumferential direction and is slidable in the axial direction. Examples of the unevenness provided on the engaged portion 112 and the lock piece 160 include serrations and splines.

[0016] A first abutment surface 113 is provided between the end face on the base end side of the engaged portion 112 and the outer circumferential surface, which is an abutment surface that inclines so as to move away from the first shaft 110 in the radial direction as it moves toward the tip end side. The first abutment surface 113 is a surface that first abuts against the lock piece 160 when the engaged portion 112 moves toward the base end side, and generates a force that urges the lock piece 160 radially outward as the engaged portion 112 moves further toward the base end side.

[0017] The second shaft 120 is a rod-shaped member also referred to as a lower shaft, a middle shaft, or the like, and is arranged coaxially with the first shaft 110. The second shaft 120 is arranged in a state where it is inserted into the insertion hole 111 of the first shaft 110 from the base end side. The second shaft 120 is inserted into the first shaft 110 in a fitted state, such as serration fitting or spline fitting, that allows torque to be transmitted freely and that allows movement in the axial direction (the Y-axis direction in the drawing).

[0018] The second shaft 120 is connected to a motor via a reducer 210, and is provided with a torque that assists steering. In addition, if the steering device 100 has a steer-by-wire function, the second shaft 120 is provided with a reaction force that is applied to the driver operating the operating member 200.

[0019] The first tube 130 is a cylindrical member that rotatably supports the first shaft 110 inside and moves integrally with the first shaft 110 in the axial direction. In the present embodiment, the first shaft 110 is arranged coaxially inside the first tube 130. The first tube 130 holds the first shaft 110 via a bearing 131. The first tube 130 moves integrally with the first shaft 110 in the axial direction (the Y-axis direction in the drawing) thanks to the bearing 131, and holds the first shaft 110 via the bearing 131 so that the first shaft 110 is rotatable in the circumferential direction around the axis.

[0020] The first tube 130 is a cylindrical member, and is provided with a notch 132 extending axially from the end on the base end side. The notch 132 penetrates the first tube 130 in the radial direction, and is open on the base end side. The lock piece 160 is inserted into the notch 132 so as to penetrate when the first tube 130 enters the second region (see FIG. 2). This prevents interference (friction) between the lock piece 160 and the first tube 130.

[0021] The second tube 140 is a cylindrical member that guides the first tube 130, which is inserted from the tip side, in the axial direction, and the second shaft 120 is disposed inside. In this embodiment, the second tube 140 is fixed to the vehicle body at least in the axial direction. Note that the second tube 140 may tilt with respect to the vehicle body.

[0022] A through-hole 141 through which the locking piece 160 passes is provided in the peripheral wall of the base end of the second tube 140. The second tube 140 also includes a rectangular cylindrical locking mechanism accommodating portion 142 that surrounds the through-hole 141 and protrudes radially outward from the peripheral surface of the second tube 140. The locking mechanism accommodating portion 142 guides the locking piece 160 accommodated inside in the radial direction (the Z-axis direction in the figure). The locking mechanism accommodating portion 142 fixes the locking piece 160 in the circumferential and axial directions. As a result, when the locking piece 160 engages with the engaged portion 112 of the first shaft 110, the first shaft 110 becomes unable to rotate around its axis. Furthermore, when the first tube is disposed in the second region and the first shaft 110 moves axially, the locking piece 160 slides against the engaged portion 112. That is, the second region is disposed closer to the base end than the first region, and is a region in which the first shaft 110 cannot rotate.

[0023] The movement mechanism 150 moves the first tube 130 relative to the second tube 140 in the axial direction. The movement mechanism 150 is not particularly limited, and any mechanism can be used. In the present embodiment, the movement mechanism 150 includes a feed screw 151, a feed nut (not shown), and a motor (not shown) that rotates the feed nut. In the axial direction, the feed nut is fixed to the second tube 140, and the feed screw 151 extends in the axial direction and is inserted while meshing with the feed nut. By rotating the feed nut with the motor, the feed screw 151 is moved forward and backward, and the first tube 130 fixed to the tip of the feed screw 151 is moved.

[0024] The lock piece 160 is a highly rigid member that is fixed to the second tube 140 in the axial direction (Y-axis direction in the figure) and around the axis so as to be positioned closer to the base end than the first tube 130 in the first region (see FIG. 2), and is movable in the radial direction (Z-axis direction in the figure). The first region is a region in which the first shaft 110 can rotate in the axial direction. In the present embodiment, the lock piece 160 is in the shape of a rectangular block, and the surface facing the first shaft 110 is recessed in a curved shape so as to fit along the outer peripheral surface of the engaged portion 112. The surface of the lock piece 160 facing the first shaft 110 is provided with axially extending irregularities that circumferentially engage with the irregularities provided on the outer peripheral surface of the engaged portion 112.

[0025] Between the end face of the locking piece 160 facing the second shaft 120 and the face on the tip side, there is provided a second abutment surface 161, which is an abutment surface that inclines so as to move away from the second shaft 120 in the radial direction as it moves toward the tip side. The second abutment surface 161 is a surface that first abuts against the first abutment surface 113 of the engaged part 112 when the engaged part 112 moves toward the base end side, and generates a force that moves the locking piece 160 radially outward as the engaged part 112 moves further toward the base end side.

[0026] The biasing member 170 has a plug 171 fixed to the outer end of the locking mechanism housing portion 142 as its base, and biases the locking piece 160 radially inward relative to the second tube 140. The type of biasing member 170 is not particularly limited, but in this embodiment, a helical spring is used.

[0027] Next, the operation of the steering device 100 will be described. When the vehicle's drive system, such as the engine or motor, is off, as shown in FIG. 4, the first tube 130 of the steering device 100 is disposed in the second region by the moving mechanism 150, and the rotation of the first shaft 110 is fixed by the lock piece 160. This makes it impossible to steer the vehicle, thereby preventing vehicle theft. Furthermore, even when the driver uses the operating member 200 as a support for their hands when getting in or out of the vehicle, the fixed operating member 200 can firmly support the driver. Furthermore, in the case of a vehicle capable of autonomous driving, the operating member 200 can be prevented from rotating due to vibrations of the vehicle during autonomous driving.

[0028] Next, when the driver operates the operating member 200, the movement mechanism 150 causes the first tube 130 and the first shaft 110 to protrude toward the distal end, along with the operating member 200. This disengages the locking piece 160 from the engaged portion 112, allowing the operating member 200 attached to the first shaft 110 to rotate and accept the driver's operation. From the time the locking piece 160 disengages from the engaged portion 112 until the first tube 130 is positioned at a predetermined position, the first tube 130 first passes through the second region. However, the notch 132 provided in the first tube 130 prevents the locking piece 160 from rubbing against the first tube 130. Furthermore, even when the first tube 130 moves within the first region, the locking piece 160 does not rub against not only the first tube 130 but also other components. Therefore, the durability of the steering device 100 is not impaired due to wear of the first tube 130. Furthermore, noise caused by the movement of the first tube 130 can be prevented. Furthermore, the degree of freedom in designing the steering device 100 is improved, and it is possible to ensure a long first region.

[0029] Furthermore, by providing a contact surface on the locking piece 160 and the engaged portion 112, the locking piece 160 and the engaged portion 112 can be smoothly engaged with each other. Furthermore, the locked piece 160 and the engaged portion 112 can be smoothly separated from each other when they are engaged. Therefore, the generation of strong impact by the biasing member 170 when the locking piece 160 and the engaged portion 112 engage with each other and separate from each other can be suppressed, and the generation of abnormal noise and wear due to the impact can be prevented.

[0030] Furthermore, by providing a notch 132 of a minimum width that can avoid interference with the lock piece 160 when the first tube 130 is positioned in the second region, the rigidity of the base end side of the first shaft 110 can be increased, and rattles when the first tube 130 moves in the first region and rattles when the first tube 130 is stopped in the first region during operation can be suppressed.

[0031] The present invention is not limited to the above-described embodiments. For example, the present invention may be embodied in another embodiment by arbitrarily combining the components described in this specification or by excluding some of the components. Furthermore, the present invention also includes various modifications that would occur to a person skilled in the art without departing from the spirit of the present invention, i.e., the meaning of the wording of the claims.

[0032] For example, the case where the engaged portion 112 is separate from the first shaft 110 and fixed to the first shaft 110 has been described, but the engaged portion 112 may be provided directly on the first shaft 110.

[0033] Furthermore, although the case where a contact surface is provided on both the lock piece 160 and the engaged portion 112 has been described, a contact surface may be provided on either the lock piece 160 or the engaged portion 112 .

[0034] Furthermore, the contact surface may not only be flat but also curved.

[0035] Furthermore, the shape of the lock piece 160 is not particularly limited, and any shape such as a cylinder may be adopted.

[0036] The fitting state between the first shaft 110 and the second shaft 120 is not limited to serration fitting or spline fitting, but may also be a fitting structure with a polygonal cross section, a fitting structure using a key, or the like.

[0037] 5, the first tube 130 may not have a notch, and the base end of the first shaft 110 and the engaged portion 112 may protrude from the base end of the first tube 130. [Industrial Applicability]

[0039] The present invention can be used in vehicles such as passenger cars, buses, trucks, construction machines, and agricultural machines. [Explanation of symbols]

[0040] 100...Steering device, 110...First shaft, 111...Insertion hole, 112...Engaged portion, 113...First abutment surface, 120...Second shaft, 130...First tube, 131...Bearing, 132...Notch, 133...Insertion hole, 134...Third abutment surface, 140...Second tube, 141...Through hole, 142...Lock mechanism accommodating portion, 150...Moving mechanism, 160...Lock piece, 161...Second abutment surface, 170...Biasing member, 171...Plug, 200...Operating member, 210...Reduction gear

Claims

1. A first shaft that rotatably holds an operating member at a tip end thereof; a second shaft that is inserted into the inside of the first shaft at a base end side of the first shaft, is movable relative to the first shaft in the axial direction of the first shaft, and rotates integrally with the first shaft; a first tube that rotatably supports the first shaft therein and moves integrally with the first shaft in the axial direction; a second tube that guides the first tube in the axial direction and has the second shaft disposed therein; a moving mechanism that moves the first tube in an axial direction between a first region in which the first shaft is rotatable and a second region that is located proximal to the first region and in which the first shaft is not rotatable; a lock piece that is movable radially relative to the second tube so as to be positioned closer to a base end than the first tube that is positioned in the first region; a biasing member that biases the locking piece radially inward relative to the second tube, The lock piece is When the first tube is disposed in the second region, the first tube engages with an engaged portion provided on the first shaft, thereby disabling rotation of the first shaft; The first tube is The first tube has a notch on the base end side into which the lock piece is inserted when the first tube is placed in the second region. Steering device.

2. At least one of the tip end side of the locking piece and the base end side of the engaged part has an abutment surface that is inclined from the base end side toward the tip end side. The steering device according to claim 1 .

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