Abstract: There is provided an electric power steering apparatus in which a motor housing that contains motor constituent members and has a waterproofing function and a control unit case that contains control apparatus constituent members and has a waterproofing function are provided, in which an output axle of a motor extends to the outside of the motor housing while maintaining the waterproofing function, and in which a respiratory apparatus that performs a respiratory action, based on an inner pressure change, is provided in the motor housing.

Abstract: A kit for reinforcing a rack and pinion steering system includes a bushing to be slid over an end of a steering rack and inserted into an opening of a rack housing of the rack and pinion steering assembly on the driver's side. The kit may also include a retainer to be inserted into the opening of the rack housing to ensure that the bushing remains in position inside the rack housing. The bushing includes a reinforcing side and a retaining side. The reinforcing side has a shape that mimics the shape of the space between the rack rod and the rack housing. The kit may further include an enhanced passenger side housing assembly that includes a bushing made of a wear resistant material. The passenger side bushing is disposed within a passenger side main housing. The enhanced passenger side housing assembly replaces the original passenger side housing.

Abstract: A modular steering system for vehicles can be applied in common to left-hand drive (LHD) and right-hand drive (RHD) vehicles and can avoid interference with peripheral parts. A steering housing and a reducer housing are separately provided to detachably assemble the steering housing and the reducer housing on the left or right of a rack bar housing and to adjust their mounting angles.

Abstract: The rack housing has an engaging concave section having a bottom surface configured by a bottom inclined surface that is inclined in a direction outward in the radial direction toward the opening side of the rack housing, and the rack bush comprises an engaging convex section having a top surface configured by a top inclined surface that is inclined in a direction outward in the radial direction toward the opening side of the rack housing. The top inclined surface is pressed against the bottom inclined surface toward outside in the radial direction, and the outside surface of the engaging convex section facing the opening side of the rack housing is pressed against the inner side surface of the engaging concave section facing the inner side of the rack housing.

Abstract: A steering unit for a vehicle, notably a bus. The steering unit is coupled with a suspension system and comprises: a support formed by a passenger platform and a wheel housing, a longitudinal axis, a steering knuckle with an in-wheel engine defining a transversal rotation axis which is arranged transversally with respect to the longitudinal axis, an actuator mechanism adapted for pivoting the steering knuckle. The steering knuckle further comprises a lever which is linked to the actuator mechanism and which includes a transversal portion extending transversally along the in-wheel engine. The steering unit is adapted for an articulated bus with at least two bodies, said bodies each exhibits four or eight identical and independent steering units.

Abstract: An actuator is configured to couple with a controlled member and includes first and second pistons disposed in respective internal chambers. The first piston may be moveable between first and second positions. The second piston may be moveable between third and fourth positions. The second piston may be configured not to engage the first piston when the second piston is disposed at the third position. The second piston may be configured to move the first piston to the second position as the second piston moves from the third position to the fourth position. A resilient member may be disposed to resiliently urge the second piston toward the fourth position.

Abstract: A steering gearbox is equipped with a casing, a rack shaft, and a plurality of bushes. The rack shaft is accommodated in a casing to be movable in an axial direction. The plurality of bushes support the rack shaft to be movable in the axial direction and are attached to the casing.

Abstract: A center take off rack and pinion steering system is disclosed having a rack housing which houses a rack gear having first and second ends extending through the housing. A pinion gear is coupled to the rack gear to input steering power to the rack gear. A rack yoke is coupled to, and extends between, the first and second ends of the rack gear. A yoke support is coupled to the rack housing and a yoke support slider is coupled to the rack yoke and is movable with the rack yoke relative to the yoke support. Tie rod end mounts are supported by the rack yoke, the tie rod end mounts positioned laterally intermediate the first and second ends of the rack gear.

Abstract: A rack supporting device for vehicle steering systems includes: a steering housing having a steering gear installed therein; a rack bar longitudinally inserted into the steering housing to engage with the steering gear; a tapered passage defined in an inner circumference of the steering housing, wherein the tapered passage is eccentric with an axial center of the steering housing; a rack bushing inserted between an inner circumference of the tapered passage and an outer circumference of the rack bar so that the rack bushing moves along the tapered passage and pushes the rack bar to the steering gear; and an elastic member mounted to one side of the tapered passage to provide an elastic pressing force for pushing the rack bar to the rack bushing.

Abstract: Technical solutions for compensating for lash in a steering system are described. An example method includes determining a rack pressure value based on a driver torque value and a differential pressure across a rack of the steering system. The method also includes determining a compensation friction value based on a position of a handwheel of the steering system and a speed of a vehicle equipped with the steering system. The method also includes computing a pressure value based on the rack pressure value and the compensation friction value. The method also includes generating a torque command using the pressure value, the torque command being added to the driver assist torque for the steering system.

Abstract: Construction is achieved that is able to effectively prevent the displacement in the axial direction of a ball bearing 16 that supports the middle section of a pinion shaft 6 so as to be able to rotate freely, and that is compact and low cost. A fastening groove 28b is formed around the entire circumference of a portion near an opening of the inner circumferential surface of a sub housing section 12c of a casing 10c, and a radially outside portion of a C-shaped retaining ring 29b is fastened in this fastening groove 28b. As a result, a side surface in the axial direction of a radially inside portion of the retaining ring 29b is pressed against a side surface in the axial direction of an outer ring 18 of a ball bearing 16 that is fitted inside and supported by the inner circumferential surface of the sub housing section 12c.

Abstract: A steering apparatus includes: a pinion shaft coupled to a steering wheel and having a pinion; a rack shaft having a rack engaged with the pinion and a shaft back located on opposite side of the rack with an axial center of the rack shaft in between; a rack shaft housing that houses and slidably supports the rack shaft; and a rack shaft supporting mechanism having a pressure applying member that applies a pressure onto the shaft back toward the pinion. The shaft back includes a predetermined region provided across a midpoint of the rack which corresponds to a neutral position of the steering wheel. The predetermined region is a right-to-left steering wheel angle region having a height higher than a height of any other region of the shaft back.

Abstract: An apparatus for use in turning steerable vehicle wheels includes an axially movable steering member. The steering member turns the steerable vehicle wheels upon axial movement of the steering member, A connector arm connected to the steering member is movable with the steering member. A first fastener connects the connector arm to the steering member and prevents relative movement between the steering member and the connector arm. A second fastener connects the connector arm to the steering member.

Abstract: A housing extends in an axial direction of a rack shaft connected to a pinion shaft so as to cover at least the rack shaft, and has an end portion on which a cover member is fitted to cover the end portion. The housing includes a holding portion that has an inner side sinking in a radial direction of the housing, and holds the cover member, and a plurality of convex portions that protrude in the radial direction of the housing, and are circumferentially disposed on a downstream side of the holding portion in a fit-in direction of the cover member, while separating from the holding portion by a predetermined distance in the fit-in direction.

Abstract: An aircraft electric taxi drive system may provide electric taxiing of an aircraft by integrating control of an electric drive and an engine during the taxi phase of a flight plan. In some embodiments, the engine may provide supplemental drive to the aircraft's wheels during electric taxiing. The engine may be maintained on while the electric drive provides the main driving force to the wheels. A controller may determine the criteria to operate the engine as the electric drive taxis the aircraft to achieve a target ground speed. In some embodiments, a pilot interface may integrate control of the electric drive and the engine into a single throttle control providing the pilot an intuitive and singular point to throttle the aircraft without having to decide which taxi source is providing the taxi driving force.

Abstract: A worm biasing structure biasing a worm engaged with a worm wheel includes a radial bearing and an elastic body. The radial bearing supports the worm in a radial direction. The elastic body has elasticity and biases the radial bearing toward the worm wheel in a biasing direction. The elastic body includes a low-spring rate elastic body and a high-spring rate elastic body having a higher spring rate than that of the low-spring rate elastic body in series in the biasing direction.

Abstract: A clearance compensator for a yoke may include: a yoke body installed in a housing of a steering gear box so as to support a rack bar; an elastic member pressurizing the yoke body toward the rack bar; a pressurizing unit contacted with the elastic member so as to support the elastic member; and a yoke plug unit including a yoke plug fixed to the housing and a pressurization adjusting part adjusting the extent to which the pressurizing unit supports the elastic member, and inserted and coupled to the yoke plug.

Abstract: A yoke clearance compensator is disclosed. It includes a yoke body installed in a housing of a steering gear box to support a rack bar; an elastic member to press the yoke body toward the rack bar; a press portion contacted with the elastic member to support the elastic member; and a yoke plug portion fixed to the housing to adjust the strength of supporting the elastic member by the press portion.

Abstract: A vehicle steering system includes a gear rack and a pinion engaged to the gear rack. The gear rack is movable in a translational manner relative to a housing in response to a steering input command received by the pinion. A first bracket is connected to a first end portion of the gear rack and a second bracket is connected to a second end portion of the gear rack. Each of the first and second brackets extends inwardly toward the opposite end portion of the gear rack. First and second tie rods are connected to the respective first and second brackets. The pinion is located between respective end portions of the first and second tie rods. A travel limit element is attached to and offset from the rack housing. Movement of the gear rack is controlled by engagement of the first and second brackets with the travel limit element.

Abstract: A power steering system has: a steering shaft; a pinion shaft; a torque sensor; a rack housing communicating with inside of the sensor housing; a rack shaft provided in the rack housing; a motor housing communicating with inside of the rack housing; an electric motor provided in the motor housing; an ECU housing communicating with inside of the motor housing; a motor control unit housed in the ECU housing; and a respiration valve provided at any of the sensor housing, the rack housing and the motor housing and located at an upper side with respect to an upper end of the ECU housing in vehicle-mounted state. The respiration valve has function by which air passes through each house and between inside and outside of the ECU housing so as to absorb change of expansion/contraction of the air in the ECU housing while suppressing entry of water from the outside.

Abstract: A steering apparatus includes a collision relaxation member provided on a surface of a housing, the surface being opposed to each rack end in a vehicle width direction. The collision relaxation member includes an elastic member arranged in an outer side of a rack shaft in a radial direction and absorbing a collision load from the corresponding rack end, and a shock absorbing member provided in an inner peripheral side of the elastic member and buckling by abutting of the rack end.

Abstract: In a stroke-limiter equipped integral power steering apparatus, a valve body of a spring-loaded-plunger-equipped limiter valve is configured to enable a position of the valve body relative to a housing to be adjusted in a longitudinal direction of the valve body via an intermediate sleeve.

Abstract: A wheeled vehicle includes a solid vehicle frame and a solid front axle including wheels movable to change the direction of the vehicle, a steering assembly including a steering wheel, a steering shaft coupled with the steering wheel, and a rotary output member having an end selectively movable in response to an input to the steering wheel, the solid front axle vehicle includes an electric power assist steering (EPAS) system for selectively steering the vehicle separately from any input to the steering wheel. The EPAS system includes a motor having a rotary output coupled to a steering gear and a steering rack having a longitudinal extent defining an axis having an end coupled a tie rod of the steering assembly. The longitudinal axis of the EPAS assembly is aligned with or transverse to the forward vehicle direction so its output is coupled to the output of the steering wheel and can be actuated independently.

Abstract: A steering system for a vehicle adapted to travel on a track or a guideway includes a drive shaft having a rotational axis and first and second substantially semicircular gear elements provided on the drive shaft and adapted to engage first and second racks, respectively. The first and second substantially semicircular gear elements are offset along the rotational axis of the drive shaft and are located about a common end of the drive shaft. The first substantially semicircular gear element engages the first rack when the drive shaft is rotated in a first direction while the second substantially semicircular gear element engages the second rack when the drive shaft is rotated in a second direction, the second direction being opposite to the first direction. Both first and second substantially semicircular gear elements engage the first and the second rack, respectively, when the drive shaft is in a neutral position.

Abstract: A rack and pinion steering apparatus for a heavy-duty vehicle includes a housing, a gear rack slidably coupled to the housing and including a plurality of rack gear teeth, and a pinion gear including a plurality of pinion gear teeth in meshing engagement with the plurality of rack gear teeth. The apparatus also includes a hydraulic motor including an output shaft coupled to and configured to rotate the pinion gear and a limiter coupled to the housing and configured to reduce an output steering force of the gear rack.

Abstract: A rack and pinion steering apparatus for a heavy-duty vehicle includes a housing, a gear rack slidably coupled to the housing and including a plurality of rack gear teeth, and a pinion gear including a plurality of pinion gear teeth in meshing engagement with the plurality of rack gear teeth. The apparatus also includes a hydraulic motor including an output shaft coupled to and configured to rotate the pinion gear and a limiter coupled to the housing and configured to reduce an output steering force of the gear rack.

Abstract: A vehicle having a power supply apparatus which is configured to supply an electric power to an external apparatus outside the vehicle, includes: a detecting unit which is configured to detect a state where a cable is pinched between an opening and closing member of the vehicle and an opening edge of an opening for the opening and closing member, the cable connecting the power supply apparatus to the external apparatus and being arranged in an interior of the vehicle; and an inhibiting unit which, when the detecting unit detects that the cable is pinched between the opening and closing member and the opening edge, is configured to inhibit running of the vehicle.

Abstract: Hydraulic steering for automobiles and self-propelled machines features at least two steering wheels and has a steering wheel linked to a hydraulic distributor, characterized in that it has at least two hydraulic modules. Each module includes a module body including an assembly having a double piston integral in translation with a rack. The piston is housed with a sliding aptitude in a cylinder body in which it delimits two opposite chambers. Each module also includes a gear meshing with the rack. Each of these modules is linked, on the one hand, through the intermediary of its pivoting element to one of the steering wheels and, on the other hand, through the intermediary of its fixed organ, to the vehicle chassis, and in that said distributor is connected to one of the chambers delimited by the rack piston of each module, the second of the chambers communicating with each other.

Abstract: This invention relates to an arrangement comprising a tubular housing, preferably a rack housing (1) that accommodates a rack (10), and at least one retention and/or support ring (2, 2?) which is disposed at least in part inside the rack housing (1) and is pressed into the housing (1) such that the retention and/or support ring (2, 2?) expands. The arrangement is characterized in that a toothed section (4, 4?) is provided on an external circumferential surface of the retention and/or support ring (2, 2?) adjoining the housing (1). The invention further relates to an associated method for mounting at least one retention and/or support ring (2, 2?) inside a tubular housing (1).

Abstract: Power steering systems and methods to improve efficiency and performance of vehicle power steering systems. In one embodiment, there is provided an engine driven positive displacement hydraulic pump, a rotary valve coupled to a steering shaft for receiving hydraulic fluid under pressure in a rotary valve inlet and providing a differential pressure to a steering rack piston for a steering boost responsive to a torque exerted on the steering shaft, valving coupled between an output of the hydraulic pump, the rotary valve inlet and the hydraulic pump input for controllably coupling the output of the hydraulic pump to the rotary valve inlet or an input of the hydraulic pump, and a controller coupled to valving to maintain a flow rate of hydraulic fluid coupled to the rotary valve responsive to a pressure sensor output. Other embodiments are disclosed.

Abstract: An apparatus (10) for use in turning steerable vehicle wheels (14, 16) includes a steering member (12) which is linearly movable relative to the vehicle to effect turning movement of the steerable vehicle wheels. A pinion (28) is disposed in meshing engagement with a rack portion (30) of the steering member (12). A steering column (22) is connected with the pinion (28) and with a vehicle steering wheel (20) such that rotation of the steering wheel results in linear movement of the steering member. An electrically powered steering unit (40) is connected to the steering member (12) for providing steering feel to the operator. A hydraulic power steering motor (60) mechanically connected to the steering member provides steering assist to the steerable wheels (14, 16).

Abstract: A steering gear of a motor vehicle is fastened to a chassis via several bearing points, each of which includes, but is not limited to bolt penetrating eyes of the chassis and the steering gear and an elastic sleeve. The elastic sleeve of at least a first of the bearing points is accommodated in the eye of the chassis.

Abstract: In a center-takeoff-type steering apparatus for a vehicle, radiant heat from a heat source such as an engine is shut off reliably. The bracket is fixed to a central portion of a rack bar for unitary movement, the rack bar moving in the lateral direction in accordance with a steering operation of a steering wheel. Ball joint mechanisms are assembled to the bracket. The ball joint mechanisms rotatably support the inboard ends of the tie rods, swing tie rods in accordance with the movement of the rack bar to thereby steer the left and right front wheels. The heat insulator is integrally formed to have an upper plate portion and a lower plate portion facing each other, and fixed to the bracket so as to cover the ball joint mechanisms.

Abstract: Joint arrangement for a vehicle, with a joint (7), which has a joint housing (8) and a pivot pin (9) mounted movably in relation thereto; a rod (4), which has a cavity (6) and which is connected to the joint (7); a ring element arranged between the joint and the rod; a sealing bellows (10), which defines the interior space (11) and in which the joint (7) is arranged at least partially; and a gas-permeable connection (13), which connects the cavity (6) of the rod (4) to the interior space (11) of the sealing bellows (10), wherein at least part of the gas-permeable connection (13) is formed by at least one groove, which is formed on the ring element and opens into the interior space (11) of the sealing bellows (10).

Abstract: Power steering systems and methods to improve efficiency and performance of vehicle power steering systems. In one embodiment, there is provided an engine driven positive displacement hydraulic pump, a rotary valve coupled to a steering shaft for receiving hydraulic fluid under pressure in a rotary valve inlet and providing a differential pressure to a steering rack piston for a steering boost responsive to a torque exerted on the steering shaft, valving coupled between an output of the hydraulic pump, the rotary valve inlet and the hydraulic pump input for controllably coupling the output of the hydraulic pump to the rotary valve inlet or an input of the hydraulic pump, and a controller coupled to valving to maintain a flow rate of hydraulic fluid coupled to the rotary valve responsive to a pressure sensor output. Other embodiments are disclosed.

Abstract: A vehicle steering system includes a gear rack supported in a fixed position, a pinion gear in meshing engagement with the gear rack, a steering subsystem supporting the pinion gear and moveable in a translational manner relative to the gear rack and at least one steering arm coupled to steering subsystem and configured to steer a motive member in response to movement of the steering subsystem. The vehicle steering system is configured to remain substantially within a framework of the vehicle while steering one or more motive members of the vehicle.

Abstract: A system and method for controlling a vehicle steering system, comprising receiving at least one signal corresponding to one or more of a lateral acceleration, a longitudinal acceleration, a vertical acceleration, a suspension travel, and a vehicle speed, calculating or determining an optimum steering rack travel from the at least one signal, and limiting travel of a steering rack of the vehicle based on the optimum steering rack travel.

Abstract: A joint arrangement, for a vehicle, is provided with a joint (7), which has a joint housing (8) and a pivot pin (9) mounted movably in relation thereto. The arrangement also includes a rod (4), which has a cavity (6) and is connected to the joint (7); a sealing bellows (10), which defines an interior space (10) and in which the joint (7) is arranged at least partially; and a gas-permeable connection (13), which connects the cavity (6) of the rod (4) to the interior space (11) of the sealing bellows (10) and has at least one groove (15), which is formed in a front side (21) of the joint (7), which said front side faces the rod (4), opens into the interior space (11) and has a radially outer end (27). The groove (15) with its radially outer end ends at a spaced location from the outer circumferential contour of the front surface (21).

Abstract: The invention relates to an electrical power steering system for a motor vehicle with a steering housing, in which a gear system is arranged, wherein a bar mounted such as to be displaceable longitudinally in the housing is a gear element for actuating steerable wheels, and wherein the steering housing is closed off by at least one folding bellows element, which is secured on one side to the steering housing and on the other side to the bar. Rapid pressure compensation in the event of temperature change is guaranteed, because a hose is connected at one end such as to communicate with the interior volumes of the steering housing, and when in operation is secured at a second free end above the steering housing.

Abstract: The invention relates to a rack-and-pinion power steering system for motor vehicles, with a steering housing, in which a gear rack (1) is mounted such as to be longitudinally displaceable, and with a gear system for converting a rotational movement of a servomotor into a longitudinal movement of the gear rack (1), with which the gear system for converting a rotational movement into a longitudinal movement is a hydrostatic spindle drive with a nut (3).

Abstract: A hydraulic power steering system for a vehicle, e.g., an electrohydraulic power steering system for a motor vehicle, includes a servo valve, the relative movement of whose control parts actuates a piston rod of a servo cylinder and changes at least one steering angle of a wheel which is operatively connected to the piston rod, and additionally has an electric servo motor which drives a rack with the servo cylinder for adjusting the steering angle of the wheel in the same direction. In order to provide an electrohydraulic power steering system which is as compactly arranged as possible in the region of its actuator and may be used flexibly for different classes of vehicle, the action of the rack and the piston rod of the servo cylinder is combined, in a parallel arrangement with one another, on an addition member for jointly adjusting the steering angle of the wheel.

Abstract: A planet gear mechanism 19 interposed between a steering 2 and steerable wheels 4L and 4R is interposed. A torque controlling motor 25 for controlling a torque acting on the steering 2 and a transmission-rate varying motor 20 for driving the planet gear mechanism 19 are arranged coaxially (on an axial A) with the planet gear mechanism 19. This eliminates the need for arranging each motor 20 and 25 on the both ends of the axis A to face each other, and also reduces a space occupied by the motors 20 and 25 with respect to a radial direction of the axis A. As a result, reduction in the size of an apparatus can be achieved.

Abstract: A steering device for steering front wheels of a four-wheeled vehicle is disclosed, comprising a steering wheel, a steering column, a lower column, and a steering gear box. The lower column is coupled via universal joints to the steering column and the steering gear box. The steering gear box includes a housing in which a rack and a screw rod are accommodated. The rack has an end coupled via a spherical joint to a tie rod, which is jointed to the front wheel. The spherical joint includes an anti-loosening washer. The housing has an inside surface forming a step over which a sleeve is fit for being engageable with the anti-loosening washer of the spherical joint to form a constraint to an inward travel of the spherical joint of the tie rod into the housing so as to set a constraint to steering angle of the front wheel.

Abstract: A steering gear for a rack and pinion steering system, including a housing in which a steering rack is guided for displacement along its axis, has an auxiliary support which is located at an axial end of the housing, the auxiliary support limiting a bending of the steering rack.

Abstract: A variable rack stroke system includes a rack housing in which a rack bar is slidably disposed, a casing attached to the rack housing, an annular rotary member, an annular stationary member, and a switch. The annular rotary member includes grooves on an inner periphery thereof that face each other, and first protrusions protruding from the rotary member in an axial direction that have different thicknesses. The rotational phase of the rotary member is adjusted by the motor. The annular stationary member includes protruding parts on an outer periphery thereof that face each other, configured to be inserted into the grooves, and second protrusions protruding from the stationary member in the axial direction, that have different thicknesses and face the first protrusions. The stationary member is coupled with a ball joint to be coupled with the rack bar. The switch adjusts the rotational phase of the motor.

Abstract: A linear electromechanical actuator, for a steering system of the ‘center take-off’ type in a motor vehicle comprises: two electric motors each having a stator, and a rotor, a screw mechanism having an axially stationary innerscrew coupled to the rotors of the motor for rotating about an axis, and an outer nut rotationally fixed and axially translatable along the axis, a connection block, axially translatable with the nut, for connecting the nut to two tie rods of the steering system.

Abstract: A rack and pinion steering apparatus which does not need quenching of the rack shaft after gear cutting of the rack shaft in manufacturing processes is provided. The rack and pinion steering apparatus comprises a pinion shaft and a rack shaft meshing with the pinion shaft. The rack shaft is formed to have a substantially uniform hardness.

Abstract: In a power steering system, the steering state of wheels is detected based on the steering speed to judge as to whether the steering state is in turning of the steering wheel or holding of steering speed is the steering wheels. At the time of the steering operation state, the control is executed so that a difference between a torque command value to an electric motor and the actual torque thereof will become smaller. Also, at the time of the holding operation state, the control is executed so that a difference between the revolution speed of the electric motor and a revolution-speed command value thereto will become smaller.

Abstract: An electric power steering apparatus (1, 64) comprises a housing (10) for supporting a steer shaft (9) for axial slide movement, a speed reduction mechanism (23), and a motion converting mechanism (24, 76). The housing (10) includes a plurality of split housings (36, 37; 36, 37A, 70) connected to each other. The speed reduction mechanism (23) includes an output gear (22) surrounding the steer shaft (9). The motion converting mechanism (24, 76) includes a rotary sleeve (28) surrounding the steer shaft (9) and rotatable integrally with the output gear (22) and converts the rotation of the rotary sleeve (28) into axial movement of the steer shaft (9). The rotary sleeve (28) is rotatably supported by first and second bearings (30, 31) disposed on opposite sides of the output gear (22). The split housings (36, 37; 36, 37A, 70) include main split housings (37, 37A) rotatably supporting an input gear (21) and supporting the first and second bearings (30, 31).

Abstract: A steering apparatus includes an attaching bracket connecting end portions of a pair of tie rods to a rack shaft. The attaching bracket includes a base which is fixed to the rack shaft and includes at least one fixing member inserting hole through which a fixing member fixing the attaching bracket to the rack shaft is provided, and a supporting stay supporting the end portions of the pair of tie rods via ball joints respectively. The supporting stay extends from an intermediate portion of the base in an axial direction of the rack shaft. A center of the ball joint supporting the end portion of each of the tie rods is positioned offset from an axial line of the fixing member by a predetermined distance when viewed along the axial direction of the rack shaft.