JP7786185B2 - Steering device - Google Patents

Description

The present invention relates to a steering device that holds a steering member operated by a driver in a vehicle or the like.

Retractable steering devices are known that improve driver comfort during autonomous driving by moving the steering member operated by the driver to the front of the vehicle. Retractable steering devices sometimes use linkless steer-by-wire technology, in which the steering shaft that holds the steering member is not mechanically connected to the steered wheels, and the steered wheels are steered by outputting steering information (see, for example, Patent Document 1).

International Publication No. 2019/005736

However, conventional steering systems that move the steering member forward and backward relative to the driver have wiring components connected to electrical devices such as reaction devices that move forward and backward along with the steering member. These wiring components are long, and the wiring state changes as the steering member moves, causing interference with vehicle components such as brake-related components and air conditioning-related components.

The present invention was developed in consideration of the above-mentioned problems, and aims to provide a steering device that can avoid interference with vehicle components, etc.

In order to achieve the above object, one aspect of the present invention is a steering device that holds a steering member movably between an advanced position where the driver can steer and a reverse position in front of the vehicle, and includes a fixed member attached to the vehicle body, a movable member attached movably to the fixed member, a steering shaft attached to the movable member and rotatably holding the steering member, a reaction force device attached to the movable member and applying a reaction force to the steering shaft, a wiring member electrically connected to the reaction force device, and a holding member attached to the movable member on the opposite side of the fixed member to the fixed member and holding the wiring member.

According to the present invention, the wiring member is held by a holding member attached to the movable member, so that even when the steering member is extended or retracted, the wiring state of the wiring member changes in accordance with the movement of the movable member, making it possible to avoid interference with vehicle components.

FIG. 2 is a perspective view showing a steering device holding a steering member. FIG. 2 is a perspective view showing a fixing member and a member attached to the fixing member. FIG. 2 is a perspective view showing a movable member and a member that moves together with the movable member. FIG. 2 is a perspective view showing a steering device with fixed members, movable members, etc. omitted. FIG. 2 is a side view showing the steering device in an advanced state with a portion thereof omitted. FIG. 2 is a side view showing the steering device in a reverse position with a portion thereof omitted.

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 merely 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 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 are 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.

Furthermore, multiple inventions may be collectively described below as a single embodiment. Some of the content described below is also described as optional components related to the present invention.

Figure 1 is a perspective view of a steering device holding a steering member. Figure 2 is a perspective view of a fixed member. Figure 3 is a perspective view of a movable member. Figure 4 is a perspective view of the steering device omitting the fixed member, movable member, etc. The steering device 100 is a device that holds a steering member 200 so that it can move between an advanced position where the driver can steer and a reverse position which is a position in front of the vehicle, and includes a fixed member 110, a movable member 120, a steering shaft 130, a reaction force device 140, a wiring member 180, and a holding member 125. In this embodiment, the steering device 100 includes a support member 143, a control device 144, a torque detection device 150, a reaction force transmission device 160, a steering angle sensor 171, a reducer 172, and a rotation amount restriction device 173.

The fixed member 110 is a member fixedly attached to a reinforcement, which is one of the structural members of the vehicle body. The manner in which the fixed member 110 is attached to the vehicle body is not limited, but in this embodiment, it is attached in a suspended state to a reinforcement stretched across the width of the vehicle body. The cross-sectional shape of the fixed member 110 perpendicular to the movement direction of the movable member 120 (X-axis direction in the figure) is an L-shape rotated 90 degrees to the right, and includes a plate-shaped fixed top panel portion 111 and a fixed wall portion 112 extending downward from one side (Y+ side in the figure) of the fixed top panel portion 111 in the width direction (Y-axis direction in the figure). A first rail 113, a component of the rail mechanism, is fixedly attached to the underside (Z- side in the figure) of the fixed top panel portion 111, extending in the movement direction of the movable member 120. A second rail 114, another component of the rail mechanism, is fixedly attached to the other widthwise side of the fixed wall 112 (the Y-side in the figure), extending in the direction of movement of the movable member 120.

A moving device 115 for moving the movable member 120 is attached below the fixed member 110 (Z-side in the figure). The type of moving device 115 is not particularly limited, but in this embodiment, it includes a feed screw 117 fixedly attached to the movable member 120 via a fixed bracket 116 so as to extend in the direction of movement of the movable member 120, a movable nut 128 that meshes with the feed screw 117 and reciprocates in the direction of movement of the movable member 120 as the feed screw 117 rotates, and a rotation drive device 118 equipped with a motor that rotates the feed screw 117.

In this embodiment, a control device 144 is fixedly attached to the outside of the fixed wall portion 112 of the fixed member 110. The control device 144 is a so-called ECU (Electronic Control Unit) or the like, and is electrically connected to the reaction force device 140 via wiring member 180 to control the reaction force device 140. The control device 144 may also be electrically connected to the torque detection device 150, steering angle sensor 171, etc. In this way, the control device 144 and the fixed member 110 are unitized, eliminating the need to separately attach the control device 144 to the vehicle body and reducing the number of installation steps. The control device 144 may also be equipped with a power source such as an inverter that supplies power to the reaction force device 140.

The movable member 120 is attached to the fixed member 110 via a rail mechanism and a moving device 115 so that it can reciprocate between an advanced position and a retracted position. The cross-sectional shape of the movable member 120 perpendicular to its movement direction (the X-axis direction in the figure) is an L-shape rotated 90 degrees to the right, and it comprises a plate-shaped movable top panel 121 and a movable wall section 122 extending downward from one side (the Y+ side in the figure) of the movable top panel 121 in the width direction (the Y-axis direction in the figure). A third rail 123, which is a component of the rail mechanism and moves along the first rail 113, is fixedly attached to the top surface (the Z-side in the figure) of the movable top panel 121, extending in the movement direction. A fourth rail 124, which is another component of the rail mechanism and moves along the second rail 114, is fixedly attached to one side (the Y+ side in the figure) of the movable wall section 122 in the width direction, extending in the movement direction. The first rail 113 and third rail 123, and the second rail 114 and fourth rail 124 are connected to each other so as to be freely linearly movable via two rows of balls held by retainers.

The movable top plate 121 has a cutout 129 (see Figure 3) of a size corresponding to the extension area 139, located above (towards the Z+ side in the figure) the extension area 139, which includes an area obtained by virtually extending the steering shaft 130 forward of the vehicle (towards the X+ side in the figure). By providing the cutout 129 in the movable top plate 121, it is possible to prevent the movable member 120 from interfering with vehicle members in the retracted position, and it is possible to position the retracted position at the front of the vehicle.

The steering shaft 130 is attached to the movable member 120 and rotatably holds the steering member 200. The shape of the steering shaft 130 is not particularly limited, and examples include a cylindrical shape and a hexagonal prism shape. The cross-sectional shape and cross-sectional area of the steering shaft 130 may also change in the axial direction. In this embodiment, the steering shaft 130 is attached to the movable member 120 rotatably about its axis via a first housing 131 that is fixedly attached to the movable member 120 in a hanging state. The first housing 131 is a housing that houses part of the reaction force transmission device 160 and is equipped with a bearing (not shown) that rotatably holds the steering shaft 130. The axis of the steering shaft 130 and the direction of movement of the movable member 120 do not have to be parallel.

Extended region 139, which includes a region obtained by virtually extending steering shaft 130 toward the front of the vehicle (X+ side in the figure) and does not intersect with reaction force device 140, is a region where no components that move with movable member 120 exist. In other words, even if a vehicle component is placed within extended region 139, the movable member 120 and components that move with it will not interfere with the vehicle component. This allows the retracted positions of movable member 120 and components that move with movable member 120 to be positioned toward the front of the vehicle, lengthening the stroke of movable member 120 and components that move with movable member 120.

A steering angle sensor 171 is attached to the end of the steering shaft 130 on the driver's side (X-side in the figure). In the case of a steer-by-wire steering device 100, the rotation angle of the steering shaft 130, i.e., the steering angle of the steering member 200, is detected by the steering angle sensor 171, and the steered wheels are steered based on the signal from the steering angle sensor 171.

A rotation amount limiting device 173 is also attached to the end of the steering shaft 130 on the front side of the vehicle (the X+ side in the figure). The rotation amount limiting device 173 is a mechanism that limits the rotation angle of the steering shaft 130 within a predetermined range. In the case of a linkless steer-by-wire steering device 100, there is no connection mechanism between the steering shaft 130 and the steered wheels to limit the rotation angle, so the rotation end of the steering member 200 is determined by software by controlling the reaction force device 140. However, in cases such as when power is not supplied to the reaction force device 140, a rotation amount limiting device 173 is provided that mechanically limits the rotation of the steering member 200 within a predetermined angle range.

The reaction force device 140 is a device equipped with a motor that applies a reaction force (torque) to the steering shaft 130 that opposes the force (torque) applied by the driver to the steering member 200, in order to impart the steering feel of the steering member connected to the steered wheels by a link to the steering member 200 held in the linkless steer-by-wire steering device 100. The reaction force device 140 is fixedly attached to the movable member 120 at a position that does not intersect with the extension region 139, which is a three-dimensional region that virtually extends the steering shaft 130 forward of the vehicle. In this embodiment, the reaction force device 140 is attached in a hanging manner to the movable member 120 via the movable bracket 141 and the second housing 142, and is positioned between the movable wall portion 122 and the extension region 139. The output shaft 149 of the motor provided in the reaction force device 140 is positioned parallel to the steering shaft 130. By positioning the reaction force device 140 on the left side of the steering shaft 130 as seen by the driver, interference between the reaction force device 140 and brake-related vehicle components can be avoided, and the movable member 120 and the members that move with it can be positioned at the front of the vehicle.

The reaction force transmission device 160 is a device that transmits the reaction force generated by the reaction force device 140 to the steering shaft 130, which is arranged along the output shaft 149. There are no particular limitations on the type of reaction force transmission device 160, and examples include a transmission device using a belt and a transmission device using gears.

In this embodiment, the reaction force transmission device 160 includes a shaft side pulley 161, a reaction force side pulley 162, and a belt 163. The shaft side pulley 161 and the reaction force side pulley 162 have the same diameter. The shaft side pulley 161 is attached coaxially to the steering shaft 130, and the reaction force side pulley 162 is attached to the output shaft 149 of the reaction force device 140. The distance between the first housing 131 that holds the steering shaft 130 and the second housing 142 that holds the output shaft 149 is adjustable in the width direction (Y-axis direction in the figure), allowing the tension of the belt 163 to be adjusted.

The reducer 172 is a device that reduces the rotation of the motor provided in the reaction device 140 at a predetermined reduction ratio and transmits torque to the steering shaft 130. There are no particular limitations on the type of reducer 172, but in this embodiment, a coaxial reducer is used and is connected to the output shaft 149 of the motor provided in the reaction device 140. Note that in this embodiment, the output shaft of the motor provided in the reaction device 140 and the output shaft of the reducer 172 arranged coaxially are collectively referred to as the output shaft 149.

By locating the reducer 172 on the reaction force device 140 side rather than the steering shaft 130 side, an extension region 139 can be secured that extends far forward of the steering shaft 130 in the direction of movement of the movable member 120, making it possible to avoid interference with vehicle components and position the retracted position of the steering member 200 as far forward as possible on the vehicle.

Furthermore, by placing the reducer 172 on the reaction force device 140 side, the reduction ratio of the reaction force transmission device 160 can be made 1:1, and the input torque from the steering member 200 can be accurately measured even if the torque detection device 150 is attached coaxially to the output shaft 149 of the reaction force device 140. Therefore, the extension region 139 can be made even longer in the movement direction of the movable member 120, and interference with vehicle members can be avoided, making it possible to position the retracted position of the steering member 200 further forward on the vehicle.

The wiring member 180 is a group of electric wires, such as a harness, electrically connected to the reaction force device 140. In this embodiment, it includes a power line 181 and a signal line 182, with one end connected to a fixed connector 184 and the other end connected to a movable connector 185. The power line 181 is a group of electric wires that supplies power to the reaction force device 140, and the signal line 182 is a group of electric wires through which signals flow from the torque detection device 150, steering angle sensor 171, etc. Both the power line 181 and the signal line 182 are flat cables, with the power line 181 positioned outside the signal line 182 in the thickness direction. This allows the radius of curvature of the relatively thick power line 181 to be larger than the radius of curvature of the signal line 182, ensuring smooth movement of the power line 181 when the movable member 120 is extended or retracted.

The holding member 125 is attached to the movable member 120 on the opposite side of the fixed member 110, and holds the wiring member 180 in a suspended state. In this embodiment, the holding member 125 is formed integrally with the movable member 120, and holds the holding member 125 inserted into a hole that penetrates the movable member 120 in the movement direction (X-axis direction in the figure). The holding member 125 also has multiple holes lined up in a direction perpendicular to the movement direction of the movable member 120 (Z-axis direction in this embodiment), with a power line 181 inserted into the upper hole and a signal line 182 inserted into the lower hole. A movable-side connector 185 is attached to each hole in the holding member 125. The movable member 120, which is integral with the holding member 125, is made of metal, and the holding member 125 has a shielding function that protects the wiring member 180 from noise.

The holding member 125 is provided on the side of the reaction force device 140, hanging down below the movable top plate portion 121, between the reaction force device 140 and the movable wall portion 122 of the movable member 120. As a result, even when the movable member 120 advances or retreats, the wiring member 180 remains inside the steering device 100, between the movable wall portion 122 and the reaction force device 140, preventing the wiring member 180 from interfering with vehicle components.

The support member 143 is attached to the fixed member 110 and supports a portion of the wiring member 180 from below. In this embodiment, the support member 143 is a groove-shaped member extending in the direction of movement of the movable member 120, and accommodates and holds the wiring member 180 within the groove. The support member 143 is held by an L-shaped support bracket 186 fixed to the fixed member 110. The wiring member 180 is sandwiched between the support member 143 and the fixed member 110 and wired in a reciprocating manner. Even when the movable member 120 advances or retreats, the wiring member 180 remains inside the steering device 100, between the support member 143 and the fixed member 110. This prevents the wiring member 180 from interfering with vehicle components and ensures smooth movement of the movable member 120. A fixed-side connector 184, to which the wiring member 180 is attached, is attached to the tip of the support member 143. The fixed-side connector 184 and the control device 144 are electrically connected by fixed wiring 187.

According to the steering device 100 of the above embodiment, the wiring member 180 that electrically connects the control device 144 and the reaction force device 140 is wired inside the steering device 100, allowing the steering device 100 to be made smaller. Furthermore, because the wiring member 180 is wired between the reaction force device 140 on the left side of the steering shaft 130 as seen by the driver and the movable wall portion 122, interference between the wiring member 180 and vehicle components such as brake-related components and air conditioning-related components can be prevented even when the movable member 120 moves.

In addition, because there is no reaction force device on the front side of the steering shaft 130, interference with vehicle components on the front side of the steering shaft can be avoided when it is stored. Therefore, the retracted position of the movable member 120 can be positioned as far forward as possible on the vehicle, ensuring ample space in front of the driver when the steering member 200 is positioned in the retracted position.

The present invention is not limited to the above-described embodiments. For example, other embodiments 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 various modifications that would occur to those skilled in the art, provided that they 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 reaction force transmission device 160 may also function as a reducer by making the diameter of the shaft-side pulley 161 different from the diameter of the reaction force-side pulley 162. This makes it possible to remove the reducer 172 from the steering device 100. In this case, it is preferable to position the torque detection device 150 on the steering shaft 130. The torque detection device 150 can detect the torque input from the steering member 200 before it changes due to the reduction function, improving the torque detection accuracy.

The steering device 100 may also be equipped with a tilt mechanism that tilts the direction of movement of the movable member 120. In this case, the fixed member 110 may be attached to the vehicle body so that it can swing, or the movable member 120 may be attached to the fixed member 110 so that it can swing.

The present invention can be used in steer-by-wire steering devices for steering vehicles such as automobiles, buses, and trucks.

100...Steering device, 110...Fixed member, 111...Fixed top plate portion, 112...Fixed wall portion, 113...First rail, 114...Second rail, 115...Moving device, 116...Fixed bracket, 117...Feed screw, 118...Rotational drive device, 120...Movable member, 121...Movable top plate portion, 122...Movable wall portion, 123...Third rail, 124...Fourth rail, 125...Retaining member, 128...Movable nut, 129...Notch portion, 130...Steering shaft body, 131...First housing, 139...Extension region, 140...Reaction force device 141...movable bracket, 142...second housing, 143...support member, 144...control device, 149...output shaft, 150...torque detection device, 160...reaction force transmission device, 161...shaft side pulley, 162...reaction force side pulley, 163...belt, 171...steering angle sensor, 172...reduction gear, 173...rotation amount control device, 180...wiring member, 181...power line, 182...signal line, 184...fixed side connector, 185...movable side connector, 186...support bracket, 187...fixed wiring, 200...steering member

Claims (4)

A steering device that holds a steering member movably between an advanced position where the driver can steer and a reverse position in front of the vehicle,
a fixing member attached to the vehicle body;
a movable member attached to the fixed member so as to be movable , the movable member including a movable top plate portion and a movable wall portion extending downward from one side of the movable top plate portion in the width direction ;
a steering shaft attached to the movable member and rotatably holding the steering member;
a reaction force device attached to the movable member and applying a reaction force to the steering shaft;
a wiring member electrically connected to the reaction force device;
a holding member attached to the movable member on the opposite side of the fixed member and holding the wiring member;
a support member attached to the fixing member and supporting a part of the wiring member,
The wiring member is
The wire is wired back and forth between the movable wall portion and the reaction device while being sandwiched between the support member and the movable top plate portion.
Steering device. 2. The steering apparatus according to claim 1, wherein the holding member holds the wiring member in an inserted state and is integral with the movable member. 3. The steering device according to claim 1 , wherein a plurality of the holding members are arranged side by side in a direction perpendicular to the direction of movement of the movable member. The steering apparatus according to claim 1 , further comprising: a control device attached to the fixing member and electrically connected to the wiring member.