JP7758159B2 - Steering device - Google Patents

Description

The present invention relates to a steering device that can move an operating member such as a steering wheel operated by a driver to steer a vehicle.

Conventionally, there are steering devices that change the position of the operating member depending on the driver, and steering devices that store the operating member in the dashboard during autonomous driving and place the operating member in a position where the driver can operate it during manual driving.

For example, Patent Document 1 discloses a steering device in which a movable member to which an operating member is rotatably attached is slidably held relative to a fixed member fixed to the vehicle, and the steering device moves between an operating position where the operating member can be operated by the driver and a position in front of the vehicle where operation is no longer necessary due to automatic driving.

Japanese Patent Application Laid-Open No. 2021-109611

However, the inventors discovered that repeated application of vibrations to the operating member due to the shaking of the vehicle while in motion, or loads applied to the operating member by the driver when driving manually, to the slide mechanism that slides the movable member, causes wear in certain parts of the slide mechanism, resulting in rattles in the operating member and rattles when sliding.

The present invention is based on the findings of the above inventor and aims to suppress the occurrence of rattling due to deterioration over time in a steering device in which the position of the operating member can be changed.

In order to achieve the above-mentioned object, one aspect of the present invention is a steering device used for steering a vehicle, comprising: a fixed member fixed to the vehicle; a movable member rotatably supporting an operating member and movable relative to the fixed member; a guide mechanism for guiding the movement of the movable member relative to the fixed member; a moving device for moving the movable member relative to the fixed member; and a movement control device for controlling the moving device, wherein the movement control device comprises: a reference position determination unit for determining a reference position for positioning the movable member; an addition unit for, when advancing the movable member, deriving a position by adding an additional value different from the previous time the movable member was advanced to the reference position within a range from a predetermined lower limit distance to a predetermined upper limit distance; and a position control unit for controlling the moving device so that the movable member is positioned at the position derived by the addition unit.

According to the present invention, by changing the position of the load applied to the guide mechanism to level out wear and suppress localized wear, it is possible to suppress rattle of the operating member attached to the movable member and rattle when the movable member moves.

1 is a schematic diagram showing a configuration of a steering system according to an embodiment; 1 is a perspective view showing the appearance of a steering device according to an embodiment; FIG. 4 is an exploded perspective view of the lateral guide mechanism. FIG. 2 is an exploded perspective view showing the upper guide mechanism. FIG. 2 is a block diagram showing the functional configuration of a mobile control device. FIG. 10 is a diagram illustrating the relationship between a reference position, an additional value, a placement position, a lower limit value, and an upper limit value. FIG. 10 is a block diagram showing another example of the functional configuration of the movement control device.

Embodiments of a steering device according to the present invention will be described below with reference to the drawings. Note that the following embodiments are presented as examples to explain the present invention and are 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 embodiments are examples only 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 acceptable errors and deviations. Furthermore, expressions such as simultaneous and identical also include substantially acceptable ranges.

The drawings are schematic diagrams in which emphasis, omission, or adjustment of proportions has been made as appropriate 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.

In addition, multiple inventions may be collectively described below as a single embodiment. Also, some of the content described below is described as optional components related to the present invention.

Figure 1 is a schematic diagram showing the overall configuration of a steering system 200 according to an embodiment. The steering system 200 according to this embodiment is a device mounted on a vehicle such as a passenger car, bus, truck, construction machinery, or agricultural machinery that can switch between a manual driving mode and an automatic driving mode.

As shown in Figure 1, the steering system 200 comprises a steering device 100 having an operating member 210 operated by the driver, and a steering mechanism 230 that steers the steerable wheels 220. In manual driving mode, for example, the steering system 200 reads the rotation angle of the operating member 210 using a sensor or the like, and steers the steerable wheels 220 by moving a rack shaft 231 back and forth left and right based on the signal from the sensor or the like. Such a system is called, for example, an SBW (Steer By Wire) system.

In the steering mechanism 230, the steerable wheels 220 connected to the rack shaft 231 via tie rods 232 are steered by movement of the rack shaft 231 in the vehicle's width direction (left-right direction in Figure 1). Specifically, in manual driving mode, the steering actuator 233 operates based on signals indicating the rotation angle of the operating member 210, etc., transmitted from the steering device 100. This causes the rack shaft 231 to move in the vehicle's width direction, and the steerable wheels 220 are steered. In other words, the steerable wheels 220 are steered in response to operation of the operating member 210. In autonomous driving mode, the steering actuator 233 operates based on signals transmitted from an ECU (Electronic Control Unit) for autonomous driving provided in the vehicle, and as a result, the steerable wheels 220 are steered regardless of operation of the operating member 210. 1 illustrates a configuration in which the driving force of steering actuator 233 is transmitted to rack shaft 231 using a belt, but there are no particular limitations on the method of transmitting the driving force of steering actuator 233 to rack shaft 231. For example, the driving force of steering actuator 233 may be transmitted to rack shaft 231 via a pinion gear fixed to the rotation shaft of steering actuator 233.

Figure 2 is an oblique view showing the appearance of the steering device 100 according to the embodiment. Figure 2 shows the steering device 100 when the movable member 130 has moved relative to the fixed member 120 and is in a position advanced toward the driver.

The steering device 100 of this embodiment comprises an input shaft 110, a fixed member 120, a movable member 130, an upper guide mechanism 140 which is one of the guide mechanisms, a lateral guide mechanism 160 which is another of the guide mechanisms, a moving device 125, and a movement control device 190 which will be described later.

The input shaft 110 is a rod-shaped member to the tip of which is attached an operating member 210 operated by the driver to steer the vehicle, and is rotatably supported by the movable member 130. A reaction force generator, a rotation angle sensor, etc. are attached to the input shaft 110, and a reaction force is applied to the operating member 210 when the driver operates the operating member 210. The rotation angle sensor also outputs a signal to synchronize the rotational position of the operating member 210 with the steering angle of the steered wheels 220.

The fixed member 120 is a member that is fixedly attached to a reinforcement, which is one of the structural members of the vehicle body. The manner in which the fixed member 120 is attached to the vehicle body is not limited, but in this embodiment, it is attached in a suspended state to a reinforcement that is stretched across the width of the vehicle body. The cross-sectional shape of the fixed member 120 perpendicular to the direction of movement of the movable member 130 relative to the fixed member 120 (the Y-axis direction in the figure) is an L-shape rotated 90 degrees to the right, and includes a plate-shaped fixed top panel portion 121 and a fixed wall portion 122 that extends downward from one side (the X-side in the figure) of the fixed top panel portion 121 in the width direction (the X-axis direction in the figure).

A moving device 125 for moving the movable member 130 is attached below the fixed member 120 (Z-side in the figure). The type of moving device 125 is not particularly limited, but in this embodiment, it includes a feed screw 127 rotatably attached to the fixed member 120 via a fixed bracket 126 so as to extend in the movement direction of the movable member 130 (Y-axis direction in the figure), a movable nut 138 that meshes with the feed screw 127 and reciprocates in the movement direction of the movable member 130 as the feed screw 127 rotates, and a rotation drive device 128 equipped with a motor (not shown) that rotates the feed screw 127. The type of motor is not limited, but if the motor is, for example, a servo motor, the moving device 125 may include a servo amplifier or the like.

The movable member 130 is attached to the fixed member 120 so that it can move back and forth between an advanced position and a retracted position by the guide mechanisms of the upper guide mechanism 140, the lateral guide mechanism 160, and the moving device 125. The movable member 130 has an input shaft 110, which holds the operating member 210, rotatably attached to it. In this embodiment, the cross-sectional shape of the movable member 130 perpendicular to the direction of movement (the Y-axis direction in the figure), is an L-shape rotated 90 degrees to the right, and includes a plate-shaped movable top panel 131 and a movable wall portion 132 extending downward from one side (the X-side in the figure) of the movable top panel 131 in the width direction (the X-axis direction in the figure). The movable wall portion 132 is thicker than the fixed wall portion 122 in the width direction, and is provided with a through-hole 135 therein through which a harness or the like connected to an operating switch or the like can be inserted.

Figure 3 is an exploded perspective view of the lateral guide mechanism 160. Figure 4 is an exploded perspective view of the upper guide mechanism 140. The lateral guide mechanism 160 and the upper guide mechanism 140 function as guide mechanisms that guide the movement of the movable member 130 relative to the fixed member 120.

3, the side guide mechanism 160 comprises a side fixed rail 161, a side movable rail 162 slidably attached to the side fixed rail 161, and a row of multiple side rolling elements 163. The row of side rolling elements 163 is composed of multiple rolling elements aligned in the direction of movement of the side movable rail 162 relative to the side fixed rail 161. The rolling elements are arranged between a side fixed track surface 164 of the side fixed rail 161 and a side movable track surface 165 of the side movable rail 162. In this embodiment, the side fixed rail 161 has two side fixed track surfaces 164, and the side movable rail 162 has two side movable track surfaces 165. The side fixed rail 161 and the side movable rail 162 are combined so that each of the two side movable track surfaces 165 faces a side fixed track surface 164. That is, the lateral guide mechanism 160 has two pairs of opposing lateral fixed raceway surfaces 164 and lateral movable raceway surfaces 165. In each of the two pairs of lateral fixed raceway surfaces 164 and lateral movable raceway surfaces 165, a lateral rolling element row 163 is disposed between the lateral fixed raceway surface 164 and the lateral movable raceway surface 165. In this embodiment, each of the lateral fixed raceway surface 164 and the lateral movable raceway surface 165 is an elongated curved surface (inner surface of a groove) that is concave in the direction approaching the other. In this embodiment, each of the multiple rolling elements included in the lateral rolling element row 163 is a metallic sphere (bearing ball).

In this embodiment, two side spacers 166 are included between the rolling elements that make up the side rolling element row 163. These two side spacers 166 regulate the gap between the side fixed track surface 164 and the side movable track surface 165 to a predetermined distance, allowing the multiple rolling elements included in the side rolling element row 163 to roll appropriately. Furthermore, each of the multiple rolling elements included in the side rolling element row 163 is rotatably held by a plate-shaped side retainer 167 disposed between the side fixed rail 161 and the side movable rail 162. The two side spacers 166 included in the side rolling element row 163 are fixed to the side retainer 167. By being held by the side retainer 167, each of the multiple rolling elements rolls while maintaining their relative positions to each other.

In the side guide mechanism 160 configured in this manner, the side fixed rail 161 is fixed to the inside of the fixed wall portion 122 of the fixed member 120. The side movable rail 162 is fixed to the outside of the movable wall portion 132 of the movable member 130. The side movable rail 162 moves in the forward and backward directions together with the movable member 130 relative to the side fixed rail 161 attached to the fixed member 120.

When the movable member 130 moves relative to the fixed member 120, the two lateral rolling element rows 163 move in the forward/backward direction relative to the lateral fixed rail 161 and the lateral movable rail 162 while remaining held by the lateral retainer 167. The lateral fixed rail 161 and the lateral movable rail 162 each have an engagement element that abuts the lateral retainer 167. This prevents the two lateral rolling element rows 163 and the lateral retainer 167 from falling off the lateral fixed rail 161 and the lateral movable rail 162. Specifically, as shown in FIG. 3 , a lateral first fixed engagement element 168 and a lateral second fixed engagement element 169 are fixed to both ends of the lateral fixed rail 161 in the forward/backward direction. A lateral first movable engagement element 170 and a second movable engagement element 171 are fixed to both ends of the lateral movable rail 162 in the forward/backward direction. The first side movable engagement body 170 engages with the side retainer 167, thereby moving the side retainer 167 and the side rolling element row 163 in the advance direction together with the side movable rail 162. As described above, when the movable member 130 moves in the advance direction and stops at the arrangement position, the position of the side rolling element row 163 relative to the side fixed rail 161 is determined. The second movable engagement body 171 engages with the side retainer 167, thereby moving the side retainer 167 and the side rolling element row 163 in the retreat direction together with the side movable rail 162. The first side fixed engagement body 168 and the second side fixed engagement body 169 engage with the side retainer 167, stopping the movement of the side retainer 167. As a result, when the lateral movable rail 162 moves in the forward direction and the lateral first movable engagement body 170 engages with the lateral first fixed engagement body 168 via the lateral retainer 167, the movement of the lateral movable rail 162 is restricted. Also, when the lateral movable rail 162 moves in the backward direction and the second movable engagement body 171 engages with the lateral second fixed engagement body 169 via the lateral retainer 167, the movement of the lateral movable rail 162 is restricted.

4, the upper guide mechanism 140 comprises an upper fixed rail 141, an upper movable rail 142 slidably mounted on the upper fixed rail 141, and a plurality of upper rolling element rows 143. The upper rolling element row 143 is composed of a plurality of rolling elements aligned in the direction of movement (advance/retreat direction) of the upper movable rail 142 relative to the upper fixed rail 141. The upper rolling element row 143 is disposed between an upper fixed track surface 144 of the upper fixed rail 141 and an upper movable track surface 145 of the upper movable rail 142. In this embodiment, as shown in FIG. 4, the upper fixed rail 141 has four upper fixed track surfaces 144, and the upper movable rail 142 has four upper movable track surfaces 145. Each of these eight track surfaces is formed by a portion of the flat surface of the upper fixed rail 141 or the upper movable rail 142. The upper fixed rail 141 and the upper movable rail 142 are combined so that each of the four upper movable track surfaces 145 faces an upper fixed track surface 144. In other words, the upper guide mechanism 140 has four pairs of opposing upper fixed track surfaces 144 and upper movable track surfaces 145. In each of the four pairs of upper fixed track surfaces 144 and upper movable track surfaces 145, an upper rolling element row 143 is arranged between the upper fixed track surface 144 and the upper movable track surface 145. In this way, the upper guide mechanism 140 has four upper rolling element rows 143.

In this embodiment, each of the two upper rolling element rows 143 arranged below the upper movable rail 142 includes two upper spacers 146. These four upper spacers 146 regulate the separation distance between the upper fixed track surface 144 and the upper movable track surface 145 to a predetermined distance, thereby allowing the multiple rolling elements included in the upper rolling element row 143 to roll appropriately. Furthermore, the multiple rolling elements included in the upper rolling element row 143 are rotatably held by a plate-shaped upper retainer 147, just like the rolling elements. The two upper spacers 146 included in the upper rolling element row 143 are fixed to the upper retainer 147. By being held by the upper retainer 147, each of the multiple rolling elements rolls while maintaining their relative positions to each other.

In the upper guide mechanism 140 configured in this manner, the upper fixed rail 141 is fixed to the underside of the fixed top plate portion 121 of the fixed member 120. The upper movable rail 142 is fixed to the upper surface of the movable top plate portion 131 of the movable member 130. The upper movable rail 142 moves in the forward and backward directions together with the movable member 130 relative to the upper fixed rail 141 attached to the fixed member 120.

When the movable member 130 moves relative to the fixed member 120, the two upper rolling element rows 143, like the lateral rolling element rows 163, move in the forward/backward direction relative to the upper fixed rail 141 and upper movable rail 142 while remaining held by the upper retainer 147. The upper fixed rail 141 and upper movable rail 142 each have an engagement body that abuts against the upper retainer 147. This prevents the two upper rolling element rows 143 and upper retainer 147 from falling off the upper fixed rail 141 and upper movable rail 142. Specifically, as shown in FIG. 4, an upper first fixed engagement body 148 and an upper second fixed engagement body 149 are fixed to both ends of the upper fixed rail 141 in the forward/backward direction, respectively. An upper first movable engagement body 150 and an upper second movable engagement body 151 are fixed to both ends of the upper movable rail 142 in the forward/backward direction. The upper first movable engagement body 150 engages with the upper retainer 147, thereby moving the upper retainer 147 and the upper rolling element row 143 together with the upper movable rail 142 in the forward direction. As described above, when the movable member 130 moves in the forward direction and stops at the arrangement position, the position of the upper rolling element row 143 relative to the upper fixed rail 141 is determined. The upper second movable engagement body 151 engages with the upper retainer 147, thereby moving the upper retainer 147 and the upper rolling element row 143 together with the upper movable rail 142 in the backward direction. The upper first fixed engagement body 148 and the upper second fixed engagement body 149 engage with the upper retainer 147, stopping the movement of the upper retainer 147. As a result, when the upper movable rail 142 moves in the forward direction and the upper first movable engagement body 150 engages with the upper first fixed engagement body 148 via the upper retainer 147, the movement of the upper movable rail 142 is restricted. Also, when the upper movable rail 142 moves in the backward direction and the upper second movable engagement body 151 engages with the upper second fixed engagement body 149 via the upper retainer 147, the movement of the upper movable rail 142 is restricted.

In this embodiment, in the upper rolling element row 143 and the side rolling element row 163, the rolling elements are inserted with a negative gap between each raceway. This applies a preload to the rolling elements. This preload minimizes misalignment due to sliding of the rolling elements and cage relative to each raceway. As a result, as the movable rail moves relative to the fixed rail, the rolling elements and cage also move along with the movable rail, but the relative positions of the rolling elements and cage relative to each raceway surface at that time are uniquely determined.

Figure 5 is a block diagram showing the functional configuration of the movement control device 190. The movement control device 190 is equipped with a processor and is a device also called an ECU (Electronic Control Unit) that controls the movement device 125. The movement control device 190 is equipped with a reference position determination unit 191, an addition unit 192, and a placement control unit 193 as processing units realized by having the processor execute a program.

The reference position determination unit 191 determines a reference position, which is a reference position for advancing and positioning the movable member 130 relative to the fixed member 120. The reference position is not particularly limited and may be, for example, a predetermined value. The reference position may also be set to a position of the driver's choice, for example. Furthermore, in cases where multiple drivers of different builds use the same vehicle, the reference position determination unit 191 may select one from multiple different reference positions. In this embodiment, the reference position determination unit 191 obtains the reference position from the storage device 101.

When advancing the movable member 130 to the position determined by the reference position determination unit 191, the adder unit 192 adds an additional value different from the previous time the movable member 130 was advanced to the reference position determined by the reference position determination unit 191 within the range from a predetermined lower limit distance to a predetermined upper limit distance, thereby deriving the placement position of the movable member 130. In this embodiment, the additional value added by the adder unit 192 is a value that changes each time the movable member 130 is advanced. As shown in Figure 6, the range of change in the additional value, that is, the range from the lower limit value to the upper limit value that can be adopted for the additional value, is preferably 5 mm or less. It has been found that if the range of change in the additional value is within 5 mm, the driver can accept it without feeling uncomfortable even if the placement position of the movable member 130 changes each time from the reference value set by the driver. Specifically, the adder unit 192 limits the additional value so that the deviation from the reference position is between -2.5 mm and +2.5 mm.

The method by which the adder unit 192 adopts an additional value different from the value used the previous time the movable member 130 advanced is not particularly limited. For example, the adder unit 192 may add a predetermined reference value to the additional value each time the movable member 130 advances, and return it to the lower limit value when the upper limit value is reached. Alternatively, the adder unit 192 may randomly generate an additional value that is a multiple of the predetermined reference value and is between the lower limit value and the upper limit value. The reference value used by the adder unit 192 to determine the additional value is preferably 10% or less of the diameter of the rolling elements included in the upper rolling element row 143 and the rolling elements included in the side rolling element row 163. The reference value is selected from a range equal to or greater than the minimum distance (e.g., 0.1 mm) over which the placement control unit 193 can control the movement of the movable member 130. If the diameter of the rolling elements in the upper rolling element row 143 is different from the diameter of the rolling elements in the side rolling element row 163, the reference value may be determined based on the smallest diameter, or may be determined by statistically processing the different diameters.

The placement control unit 193 controls the moving device 125 so that the movable member 130 is positioned at the placement position calculated by the addition unit 192. For example, if the motor included in the moving device 125 is a servo motor, the moving device 125 is a device that can move the movable member a minimum distance in the retraction direction by rotating the motor a minimum angle (e.g., one pulse). For such a moving device 125, the placement control unit 193 outputs to the moving device 125 a number of pulses corresponding to the placement position. Note that the minimum distance that the moving device 125 moves the movable member 130 is not limited, but can be, for example, in the range of 0.05 mm or more to 0.5 mm. The placement control unit 193 may also update the origin position based on a signal from a sensor that acquires the origin position of the movable member 130.

According to the steering device 100 according to the embodiment described above, the movable member 130 is not always positioned at a predetermined reference position, but is positioned at a different position each time the movable member 130 advances. This allows the position of the load applied to the guide mechanisms, the lateral guide mechanism 160 and the upper guide mechanism 140, to be changed, and wear on the upper fixed track surface 144, upper movable track surface 145, lateral fixed track surface 164, and lateral movable track surface 165 can be leveled out, suppressing localized wear. This therefore suppresses rattle over time of the operating member 210 attached to the movable member 130 and rattle due to localized wear when the movable member 130 advances or retreats.

In addition, by keeping the deviation of the position of the movable member 130 from the reference position within 5 mm, the discomfort felt by the driver can be reduced.

Furthermore, if the guide mechanism uses rolling elements, the reference value used to determine the additional value can be set to 10% or less of the diameter of the rolling elements, thereby smoothly leveling out wear on the raceway surface. This makes it possible to suppress rattling of the movable member 130 even if a rolling element passes through a worn area.

The present invention is not limited to the above-described embodiments. For example, other embodiments of the present invention may be realized by arbitrarily combining the components described in this specification, or by excluding some of the components. Furthermore, the present invention also includes variations that can be obtained by making various modifications to the above-described embodiments that would occur to a person skilled in the art, provided that the modifications do not deviate from the spirit of the present invention, i.e., the meaning of the wording set forth in the claims.

For example, the movement control device 190 may include a history acquisition unit 196 that acquires a position history, which is a history of the placement position of the movable member 130, and the addition unit 192 may determine an addition value from the position history so as to place the movable member 130 in a position with a low placement rate. The placement rate may be the frequency with which the movable member 130 is placed in a specific placement position, or may be a value indicating the cumulative time that the movable member 130 is placed in a specific placement position. Specifically, the movement control device 190 may include a timing unit 194, a recording unit 195, and a history acquisition unit 196, as shown in FIG. 7.

The timing unit 194 measures the time from when the movable member 130 advances and reaches the placement position to when it moves out of the placement position.

The recording unit 195 adds the time measured by the timing unit 194 to the cumulative time linked to the placement position where the item was previously placed at the same location and stores the result in the memory device 101.

The history acquisition unit 196 acquires a placement rate as position history based on each placement position corresponding to the reference position determined by the reference position determination unit 191. The addition unit 192 determines an addition value so as to place the movable member 130 at a position with a low placement rate, which is the ratio of the time that the movable member 130 was located at each placement position corresponding to the reference position to the total time that the movable member 130 was located at each placement position. The addition unit 192 adds the determined addition value to the reference position to derive the placement position.

By placing the movable member 130 at the placement position calculated by the adder 192, the placement control unit 193 can average out the time spent at the placement position corresponding to the reference position. Therefore, wear on the upper fixed track surface 144, upper movable track surface 145, lateral fixed track surface 164, and lateral movable track surface 165, which are guide mechanisms, can be averaged out with greater precision than by leveling out the number of times the movable member 130 is placed at the placement position.

In addition, if the position at which the advancement of the movable member 130 is restricted by the engaging body provided in the guide mechanism is the reference position, the addition unit 192 may change the upper and lower limit values based on the reference position, such as setting the upper limit value to 0 mm and the lower limit value to -5 mm.

In addition, we have described a steering device 100 that is installed in an autonomously driven vehicle and that moves the operating member 210 to the front of the vehicle where the driver cannot operate it during autonomous driving, but the steering device 100 may also be installed in a vehicle that does not have an autonomous driving function.

Furthermore, the number of rolling element rows in each of the side guide mechanism 160 and the upper guide mechanism 140 may be one or more. In other words, as long as the side guide mechanism 160 has at least one side rolling element row 163, it can slide the side movable rail 162 relative to the side fixed rail 161. Similarly, as long as the upper guide mechanism 140 has at least one upper rolling element row 143, it can slide the upper movable rail 142 relative to the upper fixed rail 141. For example, the upper guide mechanism 140 may have only one upper rolling element row 143 between the inner surface of the upper fixed rail 141 and the upper surface of the upper movable rail 142. In other words, the number of upper rolling element rows 143 in the upper guide mechanism 140 may be three. In this case, it is preferable to position the upper rolling element row 143 arranged along the upper surface of the upper movable rail 142 in the center of the upper fixed rail 141 and the upper movable rail 142 in the X-axis direction, from the standpoint of achieving stable sliding movement of the upper movable rail 142.

In the lateral guide mechanism 160, the number of contact points between the rolling element and the track surface may be two, the same as in the upper guide mechanism 140. For example, a rail mechanism with the same structure as the upper guide mechanism 140 may be placed at the position of the lateral guide mechanism 160 with its thickness direction (the direction in which the fixed rail and movable rail are aligned) facing the width direction of the vehicle (the X-axis direction). In this case, the movable rail in the rail mechanism is structurally allowed to move (displace) in the vertical direction of the vehicle. However, like the upper guide mechanism 140, the rail mechanism can resist external forces in the vertical direction of the vehicle, and therefore the movement of the movable member 130 in the vertical direction of the vehicle is primarily restricted by the rail mechanism.

The rolling elements may be of a type different from ball bearings. For example, roller bearings may be used as the rolling elements and/or the rolling elements. The rolling elements and/or the rolling elements may be made of materials other than metal. For example, the rolling elements and/or the rolling elements may be made of resin.

The rail mechanisms provided in the steering device 100 do not have to be limited to the side guide mechanism 160 and the upper guide mechanism 140.

The steering device 100 may further include a tilt mechanism that changes the vertical tilt of the steering device 100. The tilt mechanism, for example, changes the vertical tilt of the fixed member 120. This allows the vertical position of the operating member 210 to be adjusted according to the driver's intentions.

The moving device 125 may drive the movement of the movable member 130 using a method other than a feed screw method. For example, the moving device 125 may drive the movement of the movable member 130 in the forward and backward directions by the extension and contraction or forward and backward movement of a rod body fixed to the movable member 130.

The present invention is useful as a steering device that can move an operating member, and can be used in vehicles equipped with wheels or tracks, such as passenger cars, buses, trucks, agricultural machinery, and construction machinery.

100...Steering device, 101...Storage device, 110...Input shaft, 120...Fixed member, 121...Fixed top plate portion, 122...Fixed wall portion, 125...Moving device, 126...Fixed bracket, 127...Screw, 128...Rotational drive device, 130...Movable member, 131...Movable top plate portion, 132...Movable wall portion, 135...Through hole, 138...Movable nut, 140...Upper guide mechanism, 141...Upper fixed rail, 142...Upper movable rail, 143...Upper rolling element row, 144...Upper fixed raceway surface, 145...Upper movable raceway surface, 146...Upper spacer, 147...Upper retainer, 148...Upper first fixed engagement body, 149...Upper second fixed engagement body, 150...Upper first movable engagement body, 151...Upper second movable engagement body , 160...Side guide mechanism, 161...Side fixed rail, 162...Side movable rail, 163...Side rolling body row, 164...Side fixed track surface, 165...Side movable track surface, 166...Side spacer, 167...Side retainer, 168...Side first fixed engagement body, 169...Side second fixed engagement body, 170...Side first movable engagement body, 171...Second movable engagement body, 190...Movement control device, 191...Reference position determination unit, 192...Adding unit, 193...Layout control unit, 194...Timekeeping unit, 195...Recording unit, 196...History acquisition unit, 200...Steering system, 210...Operating member, 220...Steered wheel, 230...Steering mechanism unit, 231...Rack shaft, 232...Tie rod, 233...Steering actuator

Claims (5)

A steering device used for steering a vehicle,
a fixing member fixed to the vehicle;
a movable member that rotatably supports an operating member and is movable relative to the fixed member;
a guide mechanism that guides movement of the movable member relative to the fixed member;
a moving device that moves the movable member relative to the fixed member;
a movement control device that controls the movement device,
The movement control device includes:
a reference position determination unit that determines a reference position at which the movable member is to be disposed;
an adder that, when advancing the movable member, adds an additional value different from that used when the movable member was previously advanced to the reference position within a range from a predetermined lower limit distance to a predetermined upper limit distance to derive a placement position;
a position control unit that controls the moving device so that the movable member is positioned at the position derived by the addition unit. 2. The steering device according to claim 1, wherein the range from the lower limit to the upper limit of the added value is 5 mm or less. The guide mechanism includes:
a fixed rail fixed to the fixed member;
a movable rail fixed to the movable member;
a rolling element disposed between the fixed rail and the movable rail;
a cage that holds the rolling elements;
3. The steering apparatus according to claim 1, further comprising: a movable engagement body fixed to the movable rail and engaging with the retainer. the additional value to be added to the reference position is a multiple of a predetermined reference value,
4. The steering device according to claim 3, wherein the reference value is selected from a range of 10% or less of the diameter of the rolling element and a minimum distance controllable by the arrangement control unit. The movement control device includes:
a history acquisition unit that acquires a position history that is a history regarding the arrangement position of the movable member;
The adding unit
The steering device according to claim 1 , wherein the additional value is determined based on the position history so as to dispose the movable member at a position with a low disposition rate.