JP2023081450A - steering device - Google Patents

Abstract

To provide a steering device that can provide a wide mounting space for an on-vehicle device disposed above a gear housing fixed to a front end portion of a steering column and easily ensures a thickness of a portion of the gear housing, which is located above a speed reducer.SOLUTION: A gear housing 11 includes a recess 34 recessed radially inward of portions located on both sides in a circumferential direction in an upper end portion on the outer circumferential surface and including a deepest part P in a portion in the front-back direction. The deepest part P is located on the back side or the front side of an upper end portion of a speed reducer (on the back side in the illustrated example).SELECTED DRAWING: Figure 7

Description

The present invention relates to a steering device for imparting a steering angle to steered wheels of an automobile.

2. Description of the Related Art Generally, a steering device for an automobile transmits rotation of a steering wheel operated by a driver to a pinion shaft of a steering gear unit through a steering shaft, an intermediate shaft, etc., and rotates the pinion shaft to the steering gear unit. A rudder angle is imparted to the steered wheels based on the conversion into linear motion of the rack shaft.

In the field of such steering systems, an electric power steering system configured to apply auxiliary power to a steering force transmission path has become widespread in order to reduce the force required to operate the steering wheel. The structure of the electric power steering device is broadly classified according to the position at which the auxiliary power is applied. For example, a column-assist type electric power steering device that applies auxiliary power to a steering shaft includes a steering column supported by the vehicle body, a steering column rotatably supported inside the steering column, and a steering wheel attached to the rear end of the steering column. a gear housing fixed to the front end of the steering column; a torque sensor and a speed reducer housed inside the gear housing; and an electric motor supported by the gear housing. A torque sensor detects the direction and magnitude of torque applied from the steering wheel to the steering shaft. The electric motor is driven and controlled using a detection signal from a torque sensor or the like, and applies auxiliary power to the steering shaft via a speed reducer. As a result, less force is required for the driver to operate the steering wheel.

On the other hand, in recent years, a steer-by-wire type steering system has been developed that includes a steering unit to which a steering wheel is attached, and a steering unit that is electrically connected to the steering unit and provides steering angles to the left and right steered wheels. is progressing. In a steer-by-wire steering system, the steering angle of a steering wheel in a steering unit is detected by a steering angle sensor. angle is given. Moreover, the steering unit has a reaction force applying function of applying a reaction force to the steering wheel. For this purpose, the steering unit includes a steering column supported by the vehicle body, a steering shaft rotatably supported inside the steering column and having a steering wheel attached to its rear end, and a steering shaft fixed to the front end of the steering column. a gear housing, a reduction gear housed inside the gear housing, an electric motor supported by the gear housing, and a torque sensor. A torque sensor detects the direction and magnitude of torque applied from the steering wheel to the steering shaft. The electric motor is driven and controlled using a detection signal from the torque sensor, a detection signal from the steering angle sensor, and the like, and applies a reaction force to the steering wheel via the speed reducer and the steering shaft.

By the way, in recent years, as one of the in-vehicle devices, there has been an increase in the number of vehicle types equipped with a head-up display device (HUD) that enables the driver to check information such as the traveling speed without taking his or her line of sight off the road. there is A head-up display device projects information such as a traveling speed onto a portion of the windshield of a vehicle located in front of the driver's face from below the portion. Therefore, the head-up display device is arranged above the steering device, as described in DE102018202562A1 (Patent Document 1), Japanese Patent No. 6377501 (Patent Document 2), and the like.

DE102018202562A1 Japanese Patent No. 6377501

The specific placement location of the head-up display device above the steering device is determined by the relationship with other members existing in the vicinity. Arrangement of a head-up display device is being considered. In this case, it is necessary to design so that the gear housing and the head-up display device do not interfere with each other.

In such a design, for example, it is conceivable to provide a recess in the upper end portion of the outer peripheral surface of the gear housing to avoid interference with the head-up display device. By providing such a concave portion, it is possible to secure a large space for arranging the head-up display device.

However, with respect to the radial direction about the central axis of the steering column, the inner diameter of the portion of the gear housing located radially outside the speed reducer is larger than the outer diameter of the speed reducer, which is determined by the performance required of the speed reducer. , should be slightly larger. Therefore, depending on the shape of the recess provided in the upper end portion of the outer peripheral surface of the gear housing, it may be difficult to ensure the thickness of the portion of the gear housing located above the speed reducer.

The present invention can ensure a wide installation space for an in-vehicle device arranged above a gear housing fixed to the front end of a steering column, and furthermore, the thickness of the portion of the gear housing located above the speed reducer can be reduced. To provide a steering device that is easy to secure.

A steering device according to one aspect of the present invention includes a steering column supported by a vehicle body, a gear housing fixed to a front end portion of the steering column, and a speed reducer housed inside the gear housing.

The gear housing includes, at the upper end portion of the outer peripheral surface, recesses that are retracted radially inward from portions located on both sides in the circumferential direction, and that have the deepest portion in a portion in the front-rear direction, and the deepest portion corresponds to the deceleration gear housing. Located aft or forward of the upper edge of the fuselage.

In the steering device according to the first aspect of the present invention, the gear housing includes a front housing that accommodates the speed reducer inside and that has an annular front mating surface facing rearward at the rear end of the gear housing; and a rear housing having an annular rear mating surface that contacts the front mating surface. The recess is provided in the front-rear direction range including the same front-rear position as the contact portion between the front-side mating surface and the rear-side mating surface in the upper end portion of the outer peripheral surface of the gear housing, and the deepest portion. is positioned rearward of the upper end of the speed reducer.

In the steering device according to the first aspect of the present invention, it is possible to employ a configuration in which the deepest portion exists at the same position in the longitudinal direction as the contact portion between the front side mating surface and the rear side mating surface.

In the steering device according to the first aspect of the present invention, the front housing has a front fitting surface on the inner peripheral surface of the rear end portion, and the rear housing has the front fitting surface on the outer peripheral surface of the front end portion. The front fitting surface has a rear fitting surface that fits into the fitting surface. The rear fitting surface is retracted radially inward from the portions located on both sides in the circumferential direction at the upper end, and the overhang plane A configuration can be employed that has a retraction flat portion that engages the portion.

A steering device according to a second aspect of the present invention comprises a torque sensor arranged inside the gear housing. The gear housing is arranged adjacent to a front housing housing the reduction gear inside and a rear side of the front housing, houses the torque sensor inside, and has a rear end facing rearward. A rear housing having an annular front mating surface, and a rear bracket having an annular rear mating surface at a front end thereof abutting the front mating surface. The recess is provided in the front-rear direction range including the same front-rear position as the contact portion between the front-side mating surface and the rear-side mating surface in the upper end portion of the outer peripheral surface of the gear housing, and the deepest portion. is positioned rearward of the upper end of the speed reducer.

In the steering device according to the second aspect of the present invention, the deepest portion is located at the same front-rear direction position as the contact portion between the front side mating surface and the rear side mating surface and/or exists on the rear side of the corresponding contact portion. configuration can be employed.

In the steering device according to the second aspect of the present invention, the rear housing has a front fitting surface on the inner peripheral surface of the rear end portion, and the rear bracket has the front fitting surface on the outer peripheral surface of the front end portion. It has a rear side fitting surface that fits into the fitting surface, and the front side fitting surface is a portion located on both sides in the circumferential direction of an upper end portion that is a circumferential portion located radially inside the recess. The rear fitting surface has an overhang flat portion that overhangs inward in the radial direction, and the rear fitting surface is retracted radially inward from the portions located on both sides in the circumferential direction at the upper end, and the overhang A configuration can be employed that has a retraction flat that engages the flat.

In the steering device according to the third aspect of the present invention, the gear housing includes a rear housing that accommodates the reduction gear inside and that has an annular rear mating surface facing forward at its front end; a front side housing having an annular front side mating surface that abuts on the rear side mating surface. The recess is provided in the front-rear direction range including the same front-rear position as the contact portion between the front-side mating surface and the rear-side mating surface in the upper end portion of the outer peripheral surface of the gear housing, and the deepest portion. is positioned forward of the upper end of the speed reducer.

In the steering device according to the third aspect of the present invention, the deepest portion is located at the same front-rear direction position as the contact portion between the front side mating surface and the rear side mating surface and/or exists on the front side of the corresponding contact portion. can be adopted.

In the steering device according to the third aspect of the present invention, the rear housing has a rear fitting surface on the inner peripheral surface of the front end portion, and the front housing has the rear fitting surface on the outer peripheral surface of the rear end portion. It has a front fitting surface that fits into the side fitting surface, and the rear fitting surface is located on both sides in the circumferential direction of the upper end portion that is the circumferential portion located radially inside the recess. The front fitting surface is retracted radially inward from the portions located on both sides in the circumferential direction at the upper end, and the projection A configuration can be employed that has a retraction flat that engages the flat.

A steering device according to one aspect of the present invention includes a steering shaft that is rotatably supported inside the steering column and has a steering wheel attached to a rear end thereof; It further comprises an output shaft rotatably supported inside the gear housing, and a torque sensor housed inside the rear housing and detecting torque input from the steering wheel to the steering shaft. The torque detected by the torque sensor is used for drive control of the electric motor supported by the gear housing. Output torque of the electric motor is transmitted to the output shaft via the reduction gear. In one aspect of the steering apparatus of the present invention, the speed reducer includes a worm wheel externally fitted and fixed to the output shaft, and a worm that meshes with the worm wheel and is rotationally driven by the electric motor. A worm reducer, wherein the upper end of the reducer is the upper end of the worm wheel.

A steering device according to one aspect of the present invention includes a tilt shaft that is arranged in a width direction of a vehicle body and that supports the gear housing so as to be able to swing relative to the vehicle body. exists at a front-rear direction position included in the front-rear direction range in which is present.

In the steering device according to one aspect of the present invention, the central axis of the tilt shaft exists at the same position in the front-rear direction as the contact portion between the front-side mating surface and the rear-side mating surface.

In the steering device according to one aspect of the present invention, the front housing has front coupling portions protruding radially outward at a plurality of locations in the circumferential direction and used to couple the front housing and the rear housing to each other. and the rear housing has rear coupling portions protruding radially outward at a plurality of locations in the circumferential direction and used to couple the front housing and the rear housing to each other. Each of the coupling portion and the rear coupling portion is arranged below the upper edge of the recess.

In the steering device according to one aspect of the present invention, each of the front joint portion and the rear joint portion is not arranged above the deepest portion of the recess.

A steering device according to one aspect of the present invention is used as a steer-by-wire steering device.

A steering device according to one aspect of the present invention is used as an electric power steering device.

According to the steering device of one aspect of the present invention, it is possible to secure a wide installation space for the in-vehicle device arranged above the gear housing fixed to the front end portion of the steering column, and the gear housing above the reduction gear. It is easy to secure the wall thickness of the part located at.

FIG. 1 is a schematic diagram showing the overall configuration of a steering device according to a first embodiment of the present invention. FIG. 2 is a perspective view of the steering unit of the first example. FIG. 3 is a side view of the steering unit of the first example. FIG. 4 is a top view of the steering unit of the first example. FIG. 5 is a rear view of the steering unit of the first example. FIG. 6 is a cross-sectional view taken along line AA of FIG. 7 is an enlarged view of the left end of FIG. 6. FIG. FIG. 8 is a perspective view of the front housing of the first example. FIG. 9 is a rear view of the front housing of the first example. FIG. 10 is a top view of the front housing of the first example. FIG. 11(a) is a cross-sectional view taken along line BB of FIG. 9, and FIG. 11(b) is a view corresponding to FIG. 11(a) regarding the structure of the comparative example. FIG. 12 is a perspective view of the rear housing of the first example. FIG. 13 is a front view of the rear housing of the first example. FIG. 14 is a top view of the rear housing of the first example. FIG. 15 is a diagram corresponding to the left end portion of FIG. 2, showing the second example of the embodiment. FIG. 16 is a diagram corresponding to the left end of FIG. 4, showing the second example. FIG. 17 is a diagram corresponding to FIG. 7, showing a third example of the embodiment of the present invention. 18 is a partially enlarged view of FIG. 17. FIG. FIG. 19 is a side view of the part corresponding to FIG. 7 regarding the third example. FIG. 20 is a view of FIG. 19 viewed from the rear side. FIG. 21 is a diagram corresponding to the upper right part of FIG. 19 regarding the fourth example of the embodiment of the invention. FIG. 22 is a view corresponding to the upper end of FIG. 20 for the fourth example. FIG. 23 is a diagram corresponding to FIG. 7, showing a fifth example of the embodiment of the present invention. FIG. 24 is a side view of the portion corresponding to FIG. 23 regarding the fifth example. FIG. 25 is a view of FIG. 24 viewed from the rear side. FIG. 26 is a view of FIG. 24 viewed from the front side. FIG. 27 is a diagram corresponding to the upper left part of FIG. 24 regarding the sixth example of the embodiment of the invention. FIG. 28 is a view corresponding to the upper end of FIG. 26, relating to the sixth example. FIG. 29 is a side view showing the steering device of the seventh example of the embodiment;

[First example]
A first example of an embodiment of the present invention will be described with reference to FIGS. 1 to 14. FIG.

A steering device according to one aspect of the present invention, including the steering device of this example, is intended for a steering device in which an in-vehicle device such as a head-up display device is arranged above a gear housing fixed to the front end of a steering column. there is In this example, the steering system of the present invention is applied to a steer-by-wire steering system. In the following description, the front-rear direction means the front-rear direction of the vehicle, the vertical direction means the vertical direction of the vehicle, and the width direction means the width direction of the vehicle.

As schematically shown in FIG. 1, the steer-by-wire steering device 1 of this example comprises a steering unit 3 to which a steering wheel 2 is attached, and a steering unit 5 for steering left and right steering wheels 4. and a control device (ECU) 6 . The steering unit 3 and the steering unit 5 are not mechanically connected but electrically connected.

The steering unit 3 measures the operation of the steering wheel 2 by the driver using a torque sensor 13 (see FIGS. 6 and 7) and a steering angle sensor (not shown), and inputs the measurement results to the control device 6 . The control device 6 controls the steering unit 5 based on various signals indicating driving conditions such as the steering torque measured by the torque sensor 13, the steering angle measured by the steering angle sensor, the vehicle speed, the yaw rate, and the acceleration. Actuator 7 is driven. As a result, the linear motion members such as the rack shaft and the screw shaft are displaced in the width direction, the left and right tie rods 8 are pushed and pulled, and the left and right steering wheels 4 are given a steering angle. The control device 6 controls the driving of the electric motor 15 (shown only in FIG. 5) of the steering unit 3 based on various signals indicating driving conditions, and applies a steering reaction force to the steering wheel 2 according to the driving conditions. .

The steering unit 3 includes a steering column 9, a gear housing 11, and a speed reducer 14, as shown in FIGS. 2 to 7 (especially FIG. 6).

The steering column 9 has a tubular shape as a whole and is supported by the vehicle body. The steering column 9 rotatably supports a steering shaft 10 inside. A steering wheel 2 (see FIG. 1) is attached to the rear end of the steering shaft 10 . A gear housing 11 is fixed to the front end of the steering column 9 . The gear housing 11 rotatably supports the output shaft 12 inside and accommodates the torque sensor 13 and the speed reducer 14 . The output shaft 12 is connected to the front end of the steering shaft 10 . The torque sensor 13 detects torque input from the steering wheel 2 to the steering shaft 10 . The speed reducer 14 transmits the output torque of an electric motor 15 (see FIG. 5) supported by the gear housing 11 to the output shaft 12 . Thereby, a steering reaction force is applied to the steering wheel 2 via the output shaft 12 and the steering shaft 10 .

In this example, the steering column 9 is supported by the vehicle body via a column support device 16 arranged above the steering column 9 .

The steering unit 3 of this example has a telescopic function that allows the longitudinal position of the steering wheel 2 to be adjusted. For this reason, the steering column 9 and the steering shaft 10 are configured so that their entire lengths are extendable.

Specifically, the steering column 9 includes an outer column 17 disposed in the middle portion in the front-rear direction, a front inner column 18 fitted in the front portion of the outer column 17 so as to be displaceable in the front-rear direction, A rear inner column 19 is fitted inside the rear side portion of the outer column 17 so as to allow relative displacement in the front-rear direction. The gear housing 11 is fixed to the front end of the front inner column 18 .

The steering shaft 10 is formed by spline-engaging a front shaft 20 arranged on the front side and a rear shaft 21 arranged on the rear side to enable torque transmission and axial relative displacement. The rear shaft 21 is rotatably supported inside the rear inner column 19 using a plurality of (two in the illustrated example) rolling bearings 22a and 22b. A rear end portion of the rear shaft 21 protrudes rearward from the inside of the rear inner column 19, and the steering wheel 2 is attached to the rear end portion.

The column support device 16 is assembled and fixed between a fixed bracket 23 fixed to the vehicle body, a displacement bracket 24 arranged below the fixed bracket 23, and between the lower surface of the fixed bracket 23 and the upper surface of the displacement bracket 24. A linear guide 25 (see FIG. 5) is provided to enable relative displacement of the displacement bracket 24 in the longitudinal direction with respect to the bracket 23 . The outer column 17 is supported by displacement brackets 24 .

2 to 6, the steering unit 3 of this example includes an electric front telescopic actuator 26 which is assembled so as to bridge between the fixed bracket 23 and the displacement bracket 24. As shown in FIGS. The front telescopic actuator 26 can displace the displacement bracket 24 relative to the fixed bracket 23 in the front-rear direction.

2 to 6, the steering unit 3 of this example includes an electrically driven rear telescopic actuator 27 which is assembled so as to bridge between the outer column 17 and the rear inner column 19. . The rear telescopic actuator 27 can displace the rear inner column 19 relative to the outer column 17 in the front-rear direction.

The steering unit 3 of this example has a tilt function that allows the vertical position of the steering wheel 2 to be adjusted. For this reason, in this example, the steering column 9, the steering shaft 10, and the gear housing 11 are pivoted vertically about a tilt shaft 28 arranged in the width direction with respect to a fixed bracket 23 fixed to the vehicle body. supported for movement. In this example, the tilt shafts 28 are coaxially provided on each of the widthwise side portions of the front end portion of the fixed bracket 23 . In this example, the outer column 17 is supported by the displacement bracket 24 so as to be vertically swingable around the tilt shaft 28 .

2 to 5, the steering unit 3 of this example includes an electric tilting actuator 29 that is assembled between the displacement bracket 24 and the outer column 17 so as to span between them. The tilt actuator 29 is capable of vertically swinging the outer column 17 about the tilt shaft 28 with respect to the displacement bracket 24 .

To adjust the longitudinal position of the steering wheel 2, the front telescopic actuator 26 is driven to displace the displacement bracket 24 relative to the fixed bracket 23 in the longitudinal direction, thereby moving the outer column 17 relative to the front inner column 18. The rear inner column 19 is relatively displaced in the longitudinal direction and/or the rear telescopic actuator 27 is driven to displace the rear inner column 19 relative to the outer column 17 in the longitudinal direction. Thereby, the longitudinal position of the steering wheel 2 is adjusted by extending and contracting the entire length of the steering column 9 and the entire length of the steering shaft 10 .

To adjust the vertical position of the steering wheel 2 , the tilt actuator 29 is driven to swing the outer column 17 vertically about the tilt shaft 28 with respect to the displacement bracket 24 . As a result, the vertical position of the steering wheel 2 is adjusted by swinging the steering column 9 and the steering shaft 10 vertically about the tilt shaft 28 .

It should be noted that the present invention can also be applied to steering devices that do not have a telescopic function and/or a tilt function. Moreover, as a specific structure for realizing the telescopic function and the tilt function, a structure different from that of this example, for example, various conventionally known structures can be adopted. These structures include a structure for manually adjusting the front/rear and vertical positions of the steering wheel.

As shown in FIGS. 2, 4, 6, and 7, the gear housing 11 is retracted radially inward from the portions located on both sides in the circumferential direction at the upper end portion (upper surface) of the outer peripheral surface, and , a concave portion 34 having the deepest portion P in a part thereof in the front-rear direction. The concave portion 34 is a portion for avoiding interference with an in-vehicle device 35 such as a head-up display device arranged above the gear housing 11 .

In this example, the gear housing 11 comprises a front housing 30 and a rear housing 31, as shown in FIGS. The front housing 30 accommodates the speed reducer 14 inside, and has an annular front mating surface 32 facing rearward at its rear end. The rear housing 31 has, at its front end, an annular rear mating surface 33 that contacts the front mating surface 32 . In this example, the recessed portion 34 is provided in the upper end portion of the outer peripheral surface of the gear housing 11 in the front-rear direction range including the same front-rear position as the contact portion between the front-side mating surface 32 and the rear-side mating surface. In this example, the torque sensor 13 is housed inside the rear housing 31 .

In this example, the recessed portion 34 is arranged in the front-rear direction intermediate portion of the upper end portion of the outer peripheral surface of the gear housing 11 . In this example, the longitudinal range Wa of the recess 34 at the upper end of the outer peripheral surface of the gear housing 11 partially overlaps the longitudinal range Wb in which the upper end of the speed reducer 14 is arranged. In this example, the upper end of the worm wheel 37 corresponds to the upper end of the reduction gear of the invention.

When carrying out the present invention, the front-rear direction range Wa of the recess at the upper end portion of the outer peripheral surface of the gear housing can be set to a different front-rear direction range. When carrying out the present invention, the front-rear dimension of the front-rear direction range Wa of the concave portion can be set arbitrarily, but it is preferable to ensure that it is larger than 2 mm.

The deepest portion P of the concave portion 34 is positioned rearward of the rear edge of the upper end portion of the speed reducer 14, that is, the rear edge of the front-rear direction range Wb. More specifically, in this example, the deepest portion P of the recessed portion 34 exists at the same position in the front-rear direction as the contact portion between the front side mating surface 32 and the rear side mating surface 33 .

When carrying out the present invention, the position of the deepest portion of the concave portion at the upper end of the outer peripheral surface of the gear housing in the front-rear direction is determined by the minimum thickness of the portion where the concave portion exists. amount), it is also possible to set a position in the front-rear direction different from that of this example. When carrying out the present invention, the radial depth dp of the deepest portion P of the recess can be arbitrarily set under the condition that the thickness of the minimum thickness portion of the portion where the recess exists can be secured to a required amount or more. is preferably ensured to be greater than 1 mm.

In this example, the recessed portion 34 has a shape whose depth increases linearly from both ends in the front-rear direction toward the deepest portion P in the front-rear direction.

However, when carrying out the present invention, the shape of the concave portion is arbitrary, and a shape different from that of this example can also be used. For example, the shape of the recess may be such that the depth increases in a curve from both ends in the front-rear direction toward the deepest portion P in the front-rear direction.

In this example, the speed reducer 14 housed inside the front housing 30 is a worm speed reducer formed by meshing a worm 36 and a worm wheel 37 . When carrying out the present invention, as a reduction gear housed inside the front housing, a reduction gear other than a worm reduction gear, for example, a reduction gear combining a plurality of spur gears, helical gears, friction rollers, etc. can also be used.

In this example, as shown in FIGS. 7 to 10, the front housing 30 includes a wheel accommodation portion 38 that accommodates the worm wheel 37 inside, and a worm accommodation portion 39 that accommodates the worm 36 inside. In this example, the front housing 30 is made of a thermoplastic resin or a light alloy such as an aluminum alloy.

The wheel housing portion 38 includes a cylindrical wheel tube portion 40 arranged around the worm wheel 37 and an annular wheel bottom portion extending radially inward from the front end of the wheel tube portion 40 . 41 and a substantially cylindrical support tube portion 42 connected to the radially inner end portion of the wheel bottom portion 41 . In this example, the front side portion of the support cylinder portion 42 protrudes forward from the front side surface of the wheel bottom portion 41 .

The wheel tube portion 40 has a front concave portion 43 forming a front portion of the concave portion 34 in a portion extending from the front-rear direction intermediate portion to the rear end portion of the upper end portion of the outer peripheral surface. In this example, the front concave portion 43 is configured by a flat surface that is inclined radially inward from the front side toward the rear side.

The wheel tubular portion 40 has an annular front mating surface 32 around the center axis of the wheel tubular portion 40 on its rear end surface. The front mating surface 32 is formed by a plane perpendicular to the central axis of the wheel tubular portion 40 .

The wheel tubular portion 40 has a front fitting surface 44 on the inner peripheral surface of the rear end portion. In this example, the front fitting surface 44 is an overhanging flat surface projecting radially inwardly from the portions located on both sides in the circumferential direction at the upper end portion, which is the circumferential portion located radially inwardly of the front recessed portion 43 . It has a part 45 . In this example, the portion of the front fitting surface 44 other than the projecting plane portion 45 is formed of a cylindrical surface. The projecting plane portion 45 is configured by a plane parallel to the central axis of the wheel tubular portion 40 .

As shown in FIG. 11(a), in the structure of this example in which the upper end portion of the front fitting surface 44 is provided with the projecting flat portion 45, as shown in FIG. 11(b), the upper end of the front fitting surface 44z Compared to the structure of the comparative example in which the entire circumference of the front fitting surface 44z is formed of a cylindrical surface, the front concave portion 43 of the rear end portion of the wheel tubular portion 40 is A large thickness can be ensured for the upper end portion (X portion), which is the portion in the circumferential direction where it is located. That is, it is easy to ensure the thickness of the upper end portion (X portion) to be equal to or larger than the necessary amount. In the structure of this example, the worm wheel 37 has a front fitting portion provided with an overhang flat portion 45 in the wheel tubular portion 40, as indicated by a phantom line (two-dot chain line) in FIG. 11(a). It is arranged inside the portion located on the front side of the surface 44 . This portion has an inner diameter larger than the diameter of the inscribed circle of the front side fitting surface 44 provided with the overhanging flat portion 45, and is between the inner peripheral surface of this portion and the outer peripheral surface of the worm wheel 37. has sufficient clearance all around. In order to arrange the worm wheel 37 inside this portion, during assembly, the worm wheel 37 is axially inserted through the rear opening of the wheel tube portion 40 and the front fitting portion provided with the projecting flat portion 45 is inserted. It must pass axially inside the mating surface 44 . When carrying out the present invention, a clearance Ca of 0.5 mm or more is secured between the worm wheel 37 and the overhanging flat portion 45 necessary for this passage in order to facilitate this passage work. It is preferable to restrict the radially inward protrusion amount of the protrusion flat portion 45 as much as possible.

The worm housing portion 39 is generally cylindrical as a whole. The worm housing portion 39 is integrally connected to the radially outer end portion of the portion of the wheel housing portion 38 in the circumferential direction outside the upper end portion. The central axis of the worm housing portion 39 is arranged at a twisted position with respect to the central axis of the wheel housing portion 38 . The internal space of the worm housing portion 39 communicates with the internal space of the wheel housing portion 38 . In this example, the worm housing portion 39 has a motor mounting flange 46 extending radially outward at one end in the axial direction.

In this example, the front housing 30 further includes front coupling portions 47 protruding radially outward at a plurality of locations in the circumferential direction. More specifically, in this example, the front housing 30 protrudes radially outward from a plurality of circumferential locations (three locations in the illustrated example) of the rear end portion of the wheel tubular portion 40 excluding the upper end portion. A front coupling portion 47 is further provided. These front coupling portions 47 are portions used to couple the front housing 30 and the rear housing 31 to each other. In this example, the rear side surfaces of these front coupling portions 47 are configured by planes that exist within the same imaginary plane as the front side mating surfaces 32 . In this example, these front joint portions 47 have joint holes 48 extending therethrough in the longitudinal direction.

In this example, each of the plurality of front coupling portions 47 is arranged below the upper edge of the recess 34 (point Q1 in FIG. 9). In other words, each of the plurality of front joint portions 47 is arranged below the horizontal line α1 passing through the point Q1 in FIG.

In this example, as shown in FIGS. 7 and 12 to 14, the rear housing 31 includes a substantially cylindrical sensor tube portion 49 arranged around the torque sensor 13 and a front side of the sensor tube portion 49. and a substantially annular support wall portion 50 extending radially inward from the end of the support wall portion 50 .

The sensor cylinder part 49 has a rear recessed part 51 forming a rear part of the recessed part 34 in the middle part in the front-rear direction of the upper end part of the outer peripheral surface. In this example, the rear concave portion 51 is formed of a flat surface that is inclined radially inward from the rear side toward the front side.

The sensor cylinder part 49 has an annular rear mating surface 33 around the center axis of the sensor cylinder part 49 at a portion adjacent to the front side of the rear recessed part 51 in the front-rear direction. The rear mating surface 33 is formed by a plane perpendicular to the central axis of the sensor tube portion 49 .

The sensor cylindrical portion 49 has a rear fitting surface 52 that fits with the front fitting surface 44 on the outer peripheral surface of the front end portion. The rear fitting surface 52 extends forward from the radial inner end of the rear mating surface 33 . In other words, the rear mating surface 33 is provided at a portion adjacent to the rear side of the rear fitting surface 52 . In this example, the rear fitting surface 52 has, at its upper end portion, retracted planar portions 53 retracted radially inward from the portions located on both sides in the circumferential direction. The retraction flat portion 53 is a portion that engages with the protruding flat portion 45 of the front fitting surface 44 when the front fitting surface 44 and the rear fitting surface 52 are fitted together. In this example, the retraction plane portion 53 is configured by a plane parallel to the central axis of the sensor cylinder portion 49 . A portion of the rear fitting surface 52 other than the retraction flat portion 53 is formed of a cylindrical surface. That is, in this example, the front fitting surface 44 and the rear fitting surface 52 are configured to fit together in a non-circular manner.

In this example, the rear housing 31 has an annular front mating surface 71 facing rearward on the rear end surface of the sensor cylindrical portion 49, which is the rear end portion. The front mating surface 71 is formed of a plane perpendicular to the central axis of the sensor tube portion 49 . The rear housing 31 has a front fitting surface 72 on the inner peripheral surface of the rear end portion of the sensor cylindrical portion 49 , which is the inner peripheral surface of the rear end portion.

In this example, the rear housing 31 further includes rear coupling portions 54 protruding radially outward at a plurality of locations in the circumferential direction. More specifically, in this example, the rear housing 31 has rear coupling portions 54 protruding radially outward from a plurality of locations (three locations in the illustrated example) in the circumferential direction of the front end portion of the sensor cylindrical portion 49 . further provide. These rear coupling portions 54 are arranged at circumferential positions aligned with the front coupling portions 47 of the front housing 30 . In this example, the front side surfaces of these front coupling portions 47 are configured by planes existing within the same imaginary plane as the rear side mating surface 33 . These front joint portions 47 have joint holes 55 extending therethrough in the front-rear direction.

In this example, each of the plurality of rear coupling portions 54 is arranged below the upper edge of the recess 34 (point Q2 in FIG. 13). In other words, each of the plurality of rear coupling portions 54 is arranged below the horizontal line α2 passing through the point Q2 in FIG. 13 .

In this example, when the front housing 30 and the rear housing 31 are combined, the front fitting surface 44 and the rear fitting surface 52 are fitted to each other, and the front mating surface 32 and the rear mating surface 33 are fitted together. abut each other. In particular, in this example, the projecting flat portion 45 of the front fitting surface 44 and the retracting flat portion 53 of the rear fitting surface 52 are engaged with each other. are non-circularly fitted to each other, the positional relationship between the front housing 30 and the rear housing 31 in the circumferential direction becomes a desired positional relationship. Further, in this example, in this state, the front housing 30 and the rear housing 31 are held together by the bolts 56 inserted through the coupling holes 48 of the front housing 30 and screwed into the coupling holes 55 of the rear housing 31. Bonded and fixed.

In this example, the gear housing 11 further comprises an annular rear bracket 57 . In this example, the rear bracket 57 has a cylindrical tubular portion 73 and an annular side plate portion 74 extending radially outward from the front end portion of the tubular portion 73 . The rear bracket 57 has an annular rear mating surface 75 that contacts the front mating surface 71 on the front side surface of the radially outer end of the side plate portion 74 , which is the front end. The rear bracket 57 has a rear fitting surface 76 fitted to the front fitting surface 72 on the outer peripheral surface of the front end portion.

In this example, when the rear housing 31 and the rear bracket 57 are combined, the front fitting surface 72 and the rear fitting surface 76 are fitted to each other, and the front mating surface 71 and the rear mating surface 76 are fitted together. 75 abut each other. Furthermore, in this state, the rear housing 31 and the rear bracket 57 are coupled and fixed to each other by the bolts 77 .

In this example, the gear housing 11 is fixed to the front end portion of the steering column 9 by internally fitting and fixing the cylindrical portion 73 of the rear bracket 57 to the front end portion of the front inner column 18 .

In this example, the rear housing 31 of the gear housing 11 is rockably supported on both sides in the width direction by the tilt shafts 28 on both sides in the width direction. In this example, the central axis L1 (see FIGS. 3, 4, and 7) of the tilt shaft 28 is arranged behind the concave portion 34 of the gear housing 11 in the front-rear direction, and , the central axis of the steering column 9 (=the central axis of the output shaft 12) L2. However, when carrying out the present invention, by suppressing the amount of rocking displacement of the recessed portion 34 when rocking the gear housing 11 about the tilt shaft 28, the in-vehicle device 35 (see FIG. 7) can be moved to the recessed portion 34. From the viewpoint of arranging closer to the surface of the tilt shaft 28, it is preferable that the center axis L1 of the tilt shaft 28 exists in the front-rear direction position included in the front-rear direction range Wa in which the recess 34 exists. From the same point of view, it is preferable that the central axis L1 of the tilt shaft 28 is positioned above the central axis L2 of the steering column 9 in the vertical direction, that is, closer to the recess 34 than the central axis L2 in the vertical direction.

In this example, the output shaft 12 includes a front output shaft 58 arranged on the front side, a rear output shaft 59 arranged on the rear side, and a torsion bar 60 connecting the front output shaft 58 and the rear output shaft 59. and In this example, the output shaft 12 is connected to the front end of the steering shaft 10 by connecting the rear end of the rear output shaft 59 and the front end of the front shaft 20 using a cylindrical joint member 61 . ing. That is, in this example, the output shaft 12 is connected to the front end portion of the steering shaft 10 via the joint member 61 .

In this example, the front output shaft 58 is rotatably supported by the support cylinder portion 42 of the front housing 30 and the support wall portion 50 of the rear housing 31 by rolling bearings 62a and 62b. The rear output shaft 59 is rotatably supported on the rear bracket 57 by a rolling bearing 62c.

The torque sensor 13 is arranged around the rear output shaft 59 inside the rear housing 31, as shown in FIG.

In this example, the electric motor 15 is coupled and fixed to the motor mounting flange 46 of the worm housing 39 . Rotation of the motor output shaft (not shown) of the electric motor 15 is transmitted to the steering shaft 10 via the worm 36 , worm wheel 37 , output shaft 12 and joint member 61 .

In this example, the worm 36 is rotatably supported inside the worm housing portion 39 by a rolling bearing 63, as shown in FIG. The worm 36 has worm teeth 64 on the outer peripheral surface of the axially intermediate portion. The worm 36 is connected to the motor output shaft of the electric motor 15 and can be rotationally driven by the electric motor 15 .

As shown in FIG. 7 , the worm wheel 37 has wheel teeth 65 meshing with the worm teeth 64 on its outer peripheral surface, and is rotatably supported inside the wheel accommodating portion 38 . For this reason, in this example, the worm wheel 37 is externally fitted and fixed to a portion of the front output shaft 58 located between the two rolling bearings 62a and 62b. Of the wheel teeth 65 of the worm wheel 37, the worm teeth 64 of the worm 36 are meshed with the circumferential portion away from the upper end, specifically the lower portion.

According to the steering device 1 of the present embodiment, it is possible to secure a wide installation space for the in-vehicle device 35 arranged above the gear housing 11 fixed to the front end portion of the steering column 9, and the speed reducer 14 in the gear housing 11 can be secured. It is easy to secure the thickness of the part located above the

That is, the steering device 1 of this example has a recess 34 for avoiding interference with the in-vehicle device 35 at the upper end portion of the outer peripheral surface of the gear housing 11 . Therefore, due to the existence of the concave portion 34, a large installation space for the in-vehicle device 35 can be secured.

In particular, in this example, the front-rear direction range Wa of the recess 34 is ensured to be wide enough to partially overlap with the front-rear direction range Wb in which the speed reducer 14 is arranged. Therefore, from the viewpoint of securing a large installation space for the in-vehicle device 35, the structure is advantageous.

The recessed part 34 has the deepest part P in a part of the front-rear direction. The deepest portion P is a portion where the thickness of the upper end portion of the gear housing 11 is reduced most. Regarding this point, in this example, the deepest portion P is located on the rear side of the rear edge of the upper end portion of the speed reducer 14 . Therefore, it is easy to ensure the thickness of the portion of the gear housing 11 located above the speed reducer 14 .

In particular, in this example, the deepest portion P of the recessed portion 34 exists at the same front-rear direction position as the contact portion between the front side mating surface 32 and the rear side mating surface 33 . Therefore, compared to a structure in which the deepest part P exists on the outer peripheral surface of the front housing, that is, a structure in which the deepest part P exists in the front recessed part, the shape of the front recessed part 43 can be simplified. Similarly, compared to a structure in which the deepest part P exists on the outer peripheral surface of the rear housing, that is, a structure in which the deepest part P exists in the rear recessed part, the shape of the rear recessed part 51 can be simplified.

Furthermore, in this example, each of the plurality of front joint portions 47 and rear joint portions 54 is arranged below the upper edge of the recess 34 (point Q1 in FIG. 9 and point Q2 in FIG. 13). Therefore, it is possible to make it difficult for the in-vehicle device 35 to interfere with each of the plurality of front coupling portions 47 and rear coupling portions 54 .

In this example, in FIG. 9, the front coupling portion 47 located on the right side of the upper portion is arranged below the upper edge (point Q1) of the recess 34, but above the deepest portion P of the recess 34. It protrudes, in other words, it protrudes above a horizontal line β1 that contacts the deepest portion P of the recess 34 . The remaining front joint portions 47, that is, the front joint portion 47 located on the left side of the upper portion and the front joint portion 47 located on the lower portion in FIG. In other words, it does not protrude above the deepest part P (horizontal line β1) of the recess 34 .

In this example, in FIG. 13, the rear coupling portion 54 located on the left side of the upper portion is arranged below the upper edge (point Q2) of the recess 34, but above the deepest portion P of the recess 34. In other words, it protrudes above a horizontal line β2 that contacts the deepest portion P of the recess 34 . The remaining rear joint portions 54, that is, in FIG. In other words, it does not protrude above the deepest part P (horizontal line β2) of the recess 34 .

When carrying out the present invention, the front coupling portion 47 located on the upper right side in FIG. 9 and the rear coupling portion 54 located on the upper left side in FIG. , it can be arranged so as not to protrude above the deepest portion P (horizontal lines β1 and β2) of the recess 34 . In this way, it is possible to make it more difficult for the in-vehicle device 35 to interfere with each of the plurality of front coupling portions 47 and rear coupling portions 54 .

[Second example]
A second example of the embodiment of the invention will be described with reference to FIGS. 15 and 16. FIG.

In this example, the central axis L1 of the tilt shaft 28 that pivotably supports the gear housing 11a with respect to the vehicle body is present at the same position in the front-rear direction as the abutting portion between the front side mating surface 32 and the rear side mating surface 33. do. More specifically, the central axis L1 of the tilt shaft 28 exists at a position passing through the upper end of the contact portion between the front mating surface 32 and the rear mating surface 33, that is, the deepest portion P of the recess . According to the structure of this example, the amount of rocking displacement of the concave portion 34 when rocking the gear housing 11a about the tilt shaft 28 can be kept small. Therefore, the in-vehicle device 35 can be arranged closer to the surface of the recess 34, and a wider installation space for the in-vehicle device 35 can be secured accordingly. Other configurations and effects are the same as those of the first example.

[Third example]
A third example of the embodiment of the invention will be described with reference to FIGS. 17 to 20. FIG.

In this example, the recess 34a present at the upper end of the outer peripheral surface of the gear housing 11b is located at the same longitudinal position as the abutting portion between the front mating surface 71 of the rear housing 31a and the rear mating surface 75 of the rear bracket 57a. It is located in the front-rear direction range Wa including. In this example, the front-rear direction range Wa of the recess 34a includes the front-rear direction range Wb in which the upper end portion of the speed reducer 14 is arranged, and the front-side mating surface 32 of the front-side housing 30a and the rear-side mating surface 33 of the rear-side housing 31a. is located on the rear side of the contact portion of the

In this example, the depth of the recessed portion 34a increases linearly from the front end toward the contact portion between the front mating surface 71 and the rear mating surface 75 in the front-rear direction. It has a shape in which the depth does not change from the position in the front-rear direction toward the rear end. That is, in this example, the deepest portion P of the recess 34a corresponds to the rear end portion of the front-rear direction range Wa whose front end portion is at the same position in the front-rear direction as the contact portion between the front-side mating surface 71 and the rear-side mating surface 75. It exists in the axial range Wp where

In this example, the recess 34a includes a front recess 43a provided at the upper end of the outer peripheral surface of the rear housing 31a and a rear recess 51a provided at the upper end of the outer peripheral surface of the side plate portion 74a of the rear bracket 57a. Combining The front concave portion 43a is formed of a flat surface that is inclined radially inward from the front side to the rear side. The rear recess 51a is formed by a plane parallel to the center axis of the rear bracket 57a.

In this example, the front fitting surface 44a of the front housing 30a and the rear fitting surface 52a of the rear housing 31a, which are fitted to each other, are formed of cylindrical surfaces over the entire circumference.

In this example, of the front fitting surface 72a of the rear housing 31a and the rear fitting surface 76a of the rear bracket 57a that are fitted to each other, the front fitting surface 72a is located radially inside the front concave portion 43a. The upper end portion, which is the portion in the circumferential direction that faces the center, has projecting flat portions 45a that project radially inward from the portions located on both sides in the circumferential direction. The rear fitting surface 76a has, at its upper end portion, retracted flat portions 53a that are retracted radially inward from the portions located on both sides in the circumferential direction and that engage with the overhanging flat portions 45a.

In this example, the presence of the overhanging flat portion 45a makes it easier to ensure the thickness of the upper end portion of the rear end portion of the rear housing 31a where the front recess portion 43a is located. Further, the projecting flat portion 45a of the front fitting surface 72a and the retracting flat portion 53a of the rear fitting surface 76a are engaged with each other. The circular fitting allows the rear housing 31a and the rear bracket 57a to have a desired positional relationship in the circumferential direction. In FIG. 18, the area around the torque sensor 13, more specifically, the area marked with a slanted grid, is an area where metal parts should not enter in order to prevent noise from entering the torque sensor 13 (hereinafter referred to as a metal prohibited area). ). In this example, since the deepest part P of the concave portion 34a is located behind the metal-forbidden area, it is easy to ensure the thickness of the portion of the rear housing 31a located above the metal-forbidden area. . Other configurations and effects are the same as those of the first example.

[Fourth example]
A fourth example of the embodiment of the invention will be described with reference to FIGS. 21 and 22. FIG.

In this example, the deepest part P of the recess 34az is positioned at the rear end edge of the front-rear direction range Wa of the recess 34az. For this reason, in this example, the rear concave portion 51az provided at the upper end portion of the outer peripheral surface of the side plate portion 74az of the rear bracket 57az is a flat surface that is inclined radially inward from the front side toward the rear side. It consists of In this example, the rear recess 51az is arranged on the same imaginary plane as the front recess 43a.

According to the structure of this example, interference with the in-vehicle device 35 can be largely avoided by the concave portion 34az compared to the structure of the third example. Other configurations and effects are the same as those of the third example.

[Fifth example]
A fifth example of the embodiment of the present invention will be described with reference to FIGS. 23 to 26. FIG.

In this example, the gear housing 11c is formed by combining a front housing 30b and a rear housing 31b.

In this example, the torque sensor 13 and the speed reducer 14 are housed inside the rear housing 31b. For this reason, in this example, the rear housing 31b includes a substantially cylindrical tubular portion 78 that accommodates the torque sensor 13a inside, and a front end portion of the tubular portion 78 that accommodates the worm wheel 37 inside. and a worm housing portion 39a that is coupled to one position in the circumferential direction of the wheel housing portion 38a and that houses the worm 36 inside. In this example, the wheel housing portion 38a has a cylindrical wheel tube portion 40a and an annular wheel bottom portion 41a extending radially inward from the rear end of the wheel tube portion 40a. . A radial inner end portion of the wheel bottom portion 41 a is coupled to a front end portion of the cylindrical portion 78 .

The rear housing 31b has an annular rear mating surface 33a facing forward on the front end surface of the wheel tubular portion 40a, which is the front end portion. The rear housing 31b has a rear fitting surface 79 on the inner peripheral surface of the front end. In this example, the rear end portion of the cylindrical portion 78 is internally fitted and fixed to the front end portion of the front inner column 18 (see FIG. 6).

In this example, the front housing 30b has a generally annular shape as a whole, and has an annular front mating surface 32a on the rear side surface of the radially outer end, which is the rear end portion, in contact with the rear mating surface 33a. have The front housing 30b has a front fitting surface 80 that fits into the rear fitting surface 79 on the outer peripheral surface of the rear end portion.

In this example, the recess 34b present at the upper end of the outer peripheral surface of the gear housing 11c is positioned in the front-rear direction range Wa including the same front-rear direction position as the contact portion between the front-side mating surface 32a and the rear-side mating surface 33a. there is In this example, the rear portion of the front-rear direction range Wa of the recess 34b overlaps with the front portion of the front-rear direction range Wb in which the upper end portion of the speed reducer 14 is arranged.

In this example, the depth of the recessed portion 34b increases linearly from the rear end portion toward the front-rear direction position of the contact portion between the front side mating surface 32a and the rear side mating surface 33a. It has a shape in which the depth does not change from the front-rear direction position of the portion toward the front end portion. That is, in this example, the deepest portion P of the recess 34b corresponds to the front end portion of the front-rear direction range Wa whose rear end portion is at the same position in the front-rear direction as the contact portion between the front-side mating surface 32a and the rear-side mating surface 33a. exists in the axial range Wp where Therefore, the deepest portion P of the recess 34b is located forward of the front-rear direction range Wb in which the upper end portion of the speed reducer 14 is arranged.

In this example, the recess 34b is formed by combining a rear recess 51b provided at the upper end of the outer peripheral surface of the rear housing 31b and a front recess 43b provided at the upper end of the outer peripheral surface of the front housing 30b. The rear concave portion 51b is formed of a flat surface that is inclined radially inward from the rear side toward the front side. The front concave portion 43b is formed by a plane parallel to the central axis of the front housing 30b.

In this example, of the rear fitting surface 79 of the rear housing 31b and the front fitting surface 80 of the front housing 30b that are fitted to each other, the rear fitting surface 79 is positioned radially inward of the rear recess 51b. The upper end portion, which is a portion in the circumferential direction, has projecting flat portions 45b that project radially inward from the portions located on both sides in the circumferential direction. The front fitting surface 80 has, at its upper end portion, retracted plane portions 53b that are retracted radially inward from the portions located on both sides in the circumferential direction and that engage with the projecting plane portions 45b.

In this example, the presence of the projecting flat portion 45b makes it easier to ensure the thickness of the upper end portion of the front end portion of the rear housing 31b where the rear recess portion 51b is located. Further, the overhanging plane portion 45b of the rear fitting surface 79 and the retracting plane portion 53b of the front fitting surface 80 are engaged with each other. The circular fitting allows the rear housing 31b and the front housing 30b to have a desired positional relationship in the circumferential direction. Other configurations and effects are the same as those of the first example.

[Sixth example]
A sixth example of the embodiment of the present invention will be described with reference to FIGS. 27 and 28. FIG.

In this example, the deepest part P of the recess 34bz is positioned at the front end edge of the front-rear direction range Wa of the recess 34bz. For this reason, in this example, the front concave portion 43bz provided at the upper end portion of the outer peripheral surface of the front housing 30bz is formed of a flat surface that is inclined radially inward from the rear side toward the front side. In this example, the front side recessed part 43bz is arrange|positioned on the same virtual plane as the rear side recessed part 51b.

According to the structure of this example, interference with the in-vehicle device 35 can be largely avoided by the concave portion 34bz compared to the structure of the fifth example. Other configurations and effects are the same as those of the fifth example.

[Seventh example]
A seventh example of the embodiment of the present invention will be described with reference to FIG.

In this example, the steering system of the present invention is applied to an electric power steering system in which a steering wheel and steered wheels are mechanically connected.

The steering device 1a of this example includes a steering unit 3 having a structure similar to that of the first example, a pair of universal joints 66a and 66b, an intermediate shaft 67, a steering gear unit 68, and a pair of tie rods 69. Prepare.

The front end of the output shaft 12 of the steering unit 3 is connected to a pinion shaft 70 of a steering gear unit 68 via a rear universal joint 66a, an intermediate shaft 67, and a front universal joint 66b. Therefore, when the driver rotates the steering wheel 2, the rotation of the steering wheel 2 is transmitted through the steering shaft 10, the output shaft 12, the rear universal joint 66a, the intermediate shaft 67, and the front universal joint 66b. It is transmitted to the pinion shaft 70 . The rotation of the pinion shaft 70 is converted into linear motion of a rack shaft (not shown) of the steering gear unit 68 meshed with the pinion shaft 70 . As a result, the pair of tie rods 69 are pushed and pulled, so that the left and right steered wheels are given a steering angle corresponding to the amount of rotational operation of the steering wheel 2 .

In this example, in the steering unit 3 , a torque sensor 13 (see FIG. 7) detects the direction and magnitude of torque applied from the steering wheel 2 to the steering shaft 10 . The electric motor 15 (see FIG. 5) rotates a worm 36 (see FIG. 7) based on a detection signal from the torque sensor 13 and a vehicle speed signal output from a vehicle speed sensor incorporated in the transmission. Auxiliary power is applied to output shaft 12 via wheels 37 (see FIG. 7). As a result, the force required for the driver to rotate the steering wheel 2 is reduced. Other configurations and effects are the same as those of the first example.

The present invention can be practiced by appropriately combining the configurations of the above-described embodiments within a range that does not cause contradiction.

Reference Signs List 1, 1a Steering device 2 Steering wheel 3 Steering unit 4 Steering wheel 5 Steering unit 6 Control device 7 Steering actuator 8 Tie rod 9 Steering column 10 Steering shaft 11, 11a, 11b, 11c Gear housing 12 Output shaft 13, 13a Torque Sensor 14 Reducer 15 Electric motor 16 Column support device 17 Outer column 18 Front inner column 19 Rear inner column 20 Front shaft 21 Rear shaft 22a, 22b Rolling bearing 23 Fixed bracket 24 Displacement bracket 25 Linear guide 26 Front telescopic actuator 27 Rear telescopic actuator 28 Tilt shaft 29 Tilt actuator 30, 30a, 30b, 30bz Front housing 31, 31a, 31b Rear housing 32, 32a Front mating surfaces 33, 33a Rear mating surfaces 34, 34a, 34az, 34b, 34bz recessed portion 35 in-vehicle device 36 worm 37 worm wheel 38, 38a wheel housing portion 39, 39a worm housing portion 40, 40a wheel cylinder portion 41, 41a wheel bottom portion 42 support cylinder portion 43, 43a, 43b, 43bz front recess portion 44, 44a Front side fitting surface 45, 45a, 45b Overhanging flat part 46 Motor mounting flange 47 Front side coupling part 48 Coupling hole 49 Sensor tube part 50 Supporting wall part 51, 51a, 51az, 51b Rear side concave part 52, 52a Rear side fitting Mating surface 53, 53a, 53b Retraction plane portion 54 Rear joint portion 55 Joint hole 56 Bolt 57, 57a, 57az Rear bracket 58 Front output shaft 59 Rear output shaft 60 Torsion bar 61 Joint member 62a, 62b, 62c Rolling bearing 63 rolling bearing 64 worm tooth 65 wheel tooth 66a, 66b universal joint 67 intermediate shaft 68 steering gear unit 69 tie rod 70 pinion shaft 71 front mating surface 72, 72a front fitting surface 73 cylindrical portion 74, 74a, 74az side plate portion 75 rear Side mating surfaces 76, 76a Rear fitting surface 77 Bolt 78 Cylindrical portion 79 Rear fitting surface 80 Front fitting surface

Claims (16)

a steering column supported by the vehicle body;
a gear housing fixed to the front end of the steering column;
a speed reducer housed inside the gear housing,
The gear housing includes, at the upper end portion of the outer peripheral surface, recesses that are retracted radially inward from portions located on both sides in the circumferential direction and that have the deepest portion in a portion in the front-rear direction,
wherein the deepest portion is located rearward or forward of the upper end portion of the speed reducer;
steering device. The gear housing includes a front housing that accommodates the speed reducer inside and has an annular front mating surface facing rearward at its rear end, and an annular rear housing that abuts on the front mating surface at its front end. a rear housing having a mating surface;
The recess is provided in the front-rear direction range including the same front-rear position as the contact portion between the front-side mating surface and the rear-side mating surface in the upper end portion of the outer peripheral surface of the gear housing,
the deepest portion is positioned rearward of the upper end portion of the speed reducer;
The steering device according to claim 1. 3. The steering device according to claim 2, wherein said deepest portion exists at the same position in the front-rear direction as a contact portion between said front side mating surface and said rear side mating surface. The front housing has a front fitting surface on the inner peripheral surface of the rear end,
The rear housing has a rear fitting surface that fits into the front fitting surface on the outer peripheral surface of the front end,
The front fitting surface has, at its upper end portion, which is a portion in the circumferential direction located radially inward of the recess, an overhanging flat portion that projects inward in the radial direction from portions located on both sides in the circumferential direction,
The rear fitting surface has, at its upper end portion, a retraction plane portion that retracts radially inward from the portions located on both sides in the circumferential direction and that engages with the projecting plane portion.
A steering device according to claim 2 or 3. A torque sensor disposed inside the gear housing,
The gear housing is arranged adjacent to a front housing that houses the speed reducer inside and a rear side of the front housing, houses the torque sensor inside, and has a rear end facing rearward. a rear housing having an annular front mating surface; and a rear bracket having an annular rear mating surface at a front end thereof abutting the front mating surface,
The recess is provided in the front-rear direction range including the same front-rear position as the contact portion between the front-side mating surface and the rear-side mating surface in the upper end portion of the outer peripheral surface of the gear housing,
the deepest portion is positioned rearward of the upper end portion of the speed reducer;
The steering device according to claim 1. 6. The steering device according to claim 5, wherein the deepest portion is located at the same front-rear direction position as the contact portion between the front side mating surface and the rear side mating surface and/or exists on the rear side of the corresponding contact portion. The rear housing has a front fitting surface on the inner peripheral surface of the rear end,
The rear bracket has a rear fitting surface that fits into the front fitting surface on the outer peripheral surface of the front end,
The front fitting surface has, at its upper end portion, which is a portion in the circumferential direction located radially inward of the recess, an overhanging flat portion that projects inward in the radial direction from portions located on both sides in the circumferential direction,
The rear fitting surface has, at its upper end portion, a retraction plane portion that retracts radially inward from the portions located on both sides in the circumferential direction and that engages with the projecting plane portion.
A steering device according to claim 5 or 6. The gear housing includes a rear housing that accommodates the speed reducer inside and has an annular rear mating surface facing forward at its front end, and an annular housing that abuts on the rear mating surface at its rear end. a front housing having a front mating surface;
The recess is provided in the front-rear direction range including the same front-rear position as the contact portion between the front-side mating surface and the rear-side mating surface in the upper end portion of the outer peripheral surface of the gear housing,
The deepest portion is located forward of the upper end of the speed reducer,
The steering device according to claim 1. 9. The steering device according to claim 8, wherein said deepest portion is located at the same position in the front-rear direction as a contact portion between said front side mating surface and said rear side mating surface and/or exists on the front side of said contact portion. The rear housing has a rear fitting surface on the inner peripheral surface of the front end,
The front housing has a front fitting surface that fits into the rear fitting surface on the outer peripheral surface of the rear end,
The rear fitting surface has, at its upper end, which is a circumferential portion located radially inwardly of the recess, an overhanging planar portion that projects radially inwardly from portions located on both sides in the circumferential direction. ,
The front fitting surface has, at its upper end portion, a retraction plane portion that retracts radially inward from the portions located on both sides in the circumferential direction and that engages with the projecting plane portion.
A steering device according to claim 8 or 9. having a tilt shaft arranged in the width direction of the vehicle body and supporting the gear housing so as to be able to swing with respect to the vehicle body;
a central axis of the tilt shaft is present at a front-rear direction position included in a front-rear direction range in which the recess exists;
A steering device according to any one of claims 1 to 10. the center axis of the tilt shaft is located at the same position in the front-rear direction as the contact portion between the front mating surface and the rear mating surface;
The steering device according to claim 11, citing any one of claims 2-10. The front housing has, at a plurality of locations in the circumferential direction, front coupling portions projecting radially outward and used to couple the front housing and the rear housing to each other;
The rear housing has, at a plurality of locations in the circumferential direction, rear joint portions protruding radially outward and used to joint the front housing and the rear housing to each other;
Each of the front coupling portion and the rear coupling portion is arranged below an upper edge of the recess,
A steering device according to any one of claims 2 to 12. Each of the front joint portion and the rear joint portion is not arranged above the deepest portion of the recess,
14. A steering device as claimed in claim 13. The steering device according to any one of claims 1 to 14, which is used as a steer-by-wire steering device. The steering device according to any one of claims 1 to 14, which is used as an electric power steering device.

Images