KR101298117B1 - Electric power steering apparatus - Google Patents

Abstract

The electric power steering apparatus includes a worm shaft having a motor and a worm gear and connected to the output shaft so as to rotate integrally with the output shaft of the motor, a worm wheel coupled to the steering shaft and engaged with the worm gear, the worm among the worm shafts. A support bearing disposed close to the motor with respect to the motor and fastened to the worm shaft, a support bearing damper for elastically supporting the support bearing to provide a damping force to the support bearing, and the worm gear among the worm shafts A tilt bearing assembly disposed remotely from the motor and fastened to the worm shaft, and a tilting mechanism for applying force to the tilt bearing assembly such that the worm shaft is tilted in a direction pushing the worm shaft.

Description

Electric power steering apparatus

The present invention relates to an electric power steering apparatus of a vehicle.

BACKGROUND ART An electric power steering apparatus that assists steering power of a vehicle using a driving force of a motor is known. Among the electric power steering devices, a column type electric power steering device has been introduced, which assists steering power by transmitting a driving force of a motor to a steering shaft such as a steering column.

The electric power steering device generally acts to drive the motor according to the driving conditions of the vehicle such as a vehicle speed sensor and a steering torque sensor so as to assist steering power and improve steering feeling.

In the column type electric power steering device, a worm gear is installed on a shaft connected to an output shaft of a motor, and a worm wheel is installed on a steering shaft so that both of the gears mesh with each other so that the driving force of the motor can be transmitted to the steering shaft.

In the conventional column type electric power steering device, the backlash is increased due to the play of gears, the manufacturing tolerances, and the like, and vibration or noise may be generated, and shocks generated from the wheels may be transmitted. There are many things that need to be improved.

The present invention has been made to solve the problems described above, the problem to be solved by the present invention is to increase the backlash due to the clearance of the gears or manufacturing tolerances in the column-type electric power steering device and vibrations It is to provide an electric power steering device that can effectively block the generation of noise and furthermore to block the shock generated by the wheel transmitted.

The electric power steering apparatus according to an embodiment of the present invention for solving the above problems is provided with a motor, a worm gear and coupled to a worm shaft and a steering shaft connected to the output shaft to rotate integrally with the output shaft of the motor. A worm wheel engaged with the worm gear, a support bearing disposed near the motor around the worm gear among the worm shafts and fastened to the worm shaft, and elastically supporting the support bearing to provide a damping force to the support bearing. A support bearing damper, a tilt bearing assembly disposed on a side away from the motor about the worm gear among the worm shafts and fastened to the worm shaft, and the tilt such that the worm shaft is tilted toward the worm wheel. With a tilting mechanism that forces the bearing assembly .

The support bearing damper may include an elastic body elastically supporting the support bearing in the axial direction and the radial direction of the worm shaft, and a case formed to surround the axial and radial outer surfaces of the elastic body.

The elastic body and the case may be provided in pairs, each separated along the longitudinal direction of the worm shaft.

The support bearing damper may be supported by a locking jaw formed in the housing into which the worm shaft is inserted and a tightening nut screwed into the housing.

A wrinkle protrusion may be formed on an inner circumferential surface of the elastic body in contact with the support bearing.

The elastic body may include a tail portion protruding from a portion supporting the side surface of the support bearing and spaced apart from the side surface of the support bearing.

The case may be formed to support an outer surface of the tail portion.

The support bearing dampers are respectively disposed on both sides of the support bearing in a state spaced apart from the side of the support bearing so as to elastically support the support bearing when the axial movement of the worm shaft becomes equal to or greater than a preset value. It may further include an auxiliary elastic body.

The auxiliary elastic body may have a stiffness greater than that of the elastic body.

The case may be formed to receive the auxiliary elastic body.

The auxiliary elastic body may be a rubber ring, a spring washer, or a plate spring.

The tilting mechanism may include a support cam having an inclined surface, an elastic member for providing an elastic force for pushing the support cam in the axial direction of the worm shaft, and the support cam and contacting the support cam and moving the tilt bearing by movement of the support cam. It may include a tilt plug which is pushed toward the assembly to press the tilt bearing assembly to tilt in the direction of the worm wheel.

The elastic member may be supported by a screw which can be adjusted in the worm shaft axial direction to elastically support the support cam.

The tilt bearing assembly may include a tilt bearing disposed around the worm shaft, a bearing case accommodating the tilt bearing, and a damping ring formed to surround an outer circumferential surface of the bearing case and formed of an elastic material. .

An outer circumferential surface of the bearing case may be provided with a depression formed along the circumferential direction, and the damping ring may be inserted into the depression.

The bearing case may have an incision to smoothly shrink in the radial direction.

The tilt bearing assembly may further include an adjuster ring and an adjuster plug for supporting the bearing case in a direction in which the motor is located.

The adjuster ring may be formed of a material having elasticity.

An inner circumferential surface of the bearing case may be provided with a slot formed along the axial direction of the worm shaft.

The tilting mechanism may include a support cam having an inclined surface, an elastic member for providing an elastic force for pushing the support cam in the axial direction of the worm shaft, and the support cam and contacting the support cam and moving the tilt bearing by movement of the support cam. It may include a tilt plug which is pushed toward the assembly to press the tilt bearing assembly to tilt in the direction of the worm wheel.

The elastic member may be supported by a screw which can be adjusted in the worm shaft axial direction to elastically support the support cam.

The damping ring may have a through hole formed therein, and the bearing case may include a protrusion inserted into the through hole and having an insertion hole formed therein, and the tilt bearing is assembled to an inner circumferential surface of the bearing case and the tilt plug is inserted into the damping ring. It can be inserted into the ball and in contact with the outer circumferential surface of the tilt bearing.

According to the present invention, the shock and vibration transmitted to the worm shaft and the support bearing can be effectively absorbed by the support bearing damper. A tilting pivot is also possible when tilting by the tilt mechanism by means of the support bearing damper.

1 is a perspective view of an electric power steering apparatus according to an embodiment of the present invention.
2 is an exploded perspective view of the electric power steering apparatus according to the embodiment of the present invention.
3 is a partial cross-sectional view taken along the line III-III of FIG. 1.
4 is a partially enlarged view of a support bearing damper of the electric power steering apparatus according to the embodiment of the present invention.
5 is a partially enlarged view of a support bearing damper of the electric power steering apparatus according to another embodiment of the present invention.
6 is an enlarged view of the tilting mechanism portion in FIG. 3.
7 is an exploded perspective view of the motor coupling of the power steering apparatus according to the embodiment of the present invention.
8 is a perspective view of a bearing case of the power steering apparatus according to the embodiment of the present invention.
9 is a perspective view of a damping ring of the power steering apparatus according to the embodiment of the invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The electric power steering apparatus according to the embodiment of the present invention is a device for providing steering assist torque by using the power of the motor.

According to an embodiment of the invention, a worm shaft 10 is provided with a worm gear 11. The worm shaft 10 is connected to the output shaft 21 to rotate integrally with the output shaft 21 of the motor 20. The connection here means that the worm shaft 10 is not only directly connected to the output shaft 21 of the motor 20 but also indirectly through another connection member (the motor coupling 30 to be described later). .

The motor 20 may be controlled to be operated by a control signal of an electronic control unit (ECU, not shown), the electronic control unit may include a steering torque sensor that detects a steering torque, a steering angle sensor that detects a steering angle, The control signal for controlling the motor 20 may be generated and output based on the signal of the vehicle speed sensor detecting the vehicle speed. Controlling the motor 20 that provides steering assistance based on steering torque, steering angle, vehicle speed, etc., may be made in a conventionally known manner, and thus detailed description thereof is omitted.

The worm gear 11 of the worm shaft 10 is engaged with the worm wheel 3 coupled to the steering shaft 1 so that the driving force of the motor 20 is applied to the worm shaft 10. It can be transmitted to the worm wheel 3 through which the steering assistance force can be transmitted to the steering shaft 1. By adopting a worm and worm wheel type reducer structure, the steering assistance force can be increased.

As shown in the figure, the worm shaft 10 may be disposed in a housing 40. To this end, a through hole is provided in the housing 40, and a worm shaft 10 is rotatably installed in the through hole of the housing 40. The motor 20 is fixed to one side of the housing 40, and the output shaft 21 of the motor 20 flows into the housing 40 and is fastened to the worm shaft 10. On the other hand, the housing 40 may be formed in a shape that can accommodate a portion of the steering shaft 1 and the worm wheel (3). That is, the worm wheel 3 and the worm shaft 10 may be disposed in a state in which the worm wheel 3 and the worm shaft 10 are fastened to each other in the housing 40.

At this time, the worm shaft 10 is driven by the motor coupling 30 to reduce shock and vibration between the worm shaft 10 and the output shaft 21 of the motor 20 and to reduce the tolerance. It may be concentrically connected to the output shaft (21) of.

Referring to FIG. 7, in accordance with an embodiment of the present invention, the motor coupling 30 may include a first member 31 fastened to the output shaft 21 of the motor 20 and a first shaft fastened to the worm shaft 10. It may include the two members 33 and the connecting member 35 interposed therebetween. The first member 31 may be splined to the output shaft 21 to rotate with the output shaft 21 of the motor 20, and the second member 33 to rotate with the worm shaft 10. It may be splined to the worm shaft 10. The connecting member 35 may be fastened to the first and second members 31 and 33 so as to rotate together with the first and second members 31 and 33, respectively.

For example, as shown in FIG. 7, the connecting member 35 has a cylindrical shape as a whole, and a plurality of recesses 35a are formed along the outer circumferential surface thereof, and a hole 35b is formed between the recesses 35a. Can be. The first member 31 is provided with a plurality of projections 31a fitted to the recessed portion 35a of the connecting member 35, and the second member 33 is provided in the hole 35b of the connecting member 35. The projection 33a fitted is provided. The projection 31a of the first member 31 is fitted into the recessed portion 35a of the connection member 35 and the projection 33a of the second member 33 is fitted into the hole 35b of the connection member 35. As a result, the first member 31, the second member 33 and the connecting member 35 rotate together. In addition, the first member 31 includes a through hole 31b into which the output shaft 21 of the motor 20 is inserted and splined thereto, and the through hole through which the worm shaft 10 is inserted into and splined into the second member 33. 33b is provided. The output shaft 21 of the motor 20 is inserted into the through hole 31b of the first member 31 so as to rotate together with the first member 31 and splined thereto, and the worm shaft 10 is connected to the second member 33. It is inserted and splined into the through hole 33b of the second member 33 so as to rotate together. Accordingly, the output shaft 21, the motor coupling 30, and the worm shaft 10 of the motor 20 are connected to each other to rotate together.

In this case, the connection member 35 of the motor coupling 30 may be formed of a material having elasticity such as rubber, and thus vibration and shock between the output shaft 21 and the worm shaft 10 of the motor 20. Can alleviate

On the other hand, the electric power steering apparatus according to the embodiment of the present invention includes a support bearing (support bearing) (400).

The support bearing 400 is disposed near the motor 20 around the worm gear 11 of the worm shaft 10 and fastened to the worm shaft 10. That is, as shown in FIG. 3, the support bearing 400 rotatably supports the worm shaft 10 between the worm gear 11 and the motor 20.

The worm shaft 10 is inserted into the through hole 410 of the support bearing 400. In this case, the worm shaft 10 may be press-fitted into the through hole 410 of the support bearing 400 in a press fitting manner.

On the other hand, the electric power steering apparatus according to another embodiment of the present invention includes a support bearing damper (support bearing damper) (200). The support bearing damper 200 elastically supports the support bearing 400 to provide a damping force to the support bearing 400. Accordingly, the support bearing damper 200 prevents generation of rattle noise, which may be caused by incomplete engagement due to impact or vibration transmitted from the wheel while driving the vehicle, and tooth wear due to durability. . That is, the support bearing damper 200 can absorb the shock and vibration by allowing the worm shaft 10 to move in the axial direction when the shock is transmitted during its operation and while driving the vehicle, and furthermore, the tilting mechanism (described later) ( The pivot shaft 300 may serve as a pivot point enabling tilting when the worm shaft 10 is tilted.

On the other hand, the support bearing damper 200 is an elastic body 210 for elastically supporting the support bearing 400 in the axial direction and the radial direction of the worm shaft 10, and the axial direction and the radial outer surface of the elastic body 210 It includes a case 220 formed to surround.

At this time, the elastic body 210 and the case 220 may be provided in pairs, each separated along the longitudinal direction of the worm shaft 10. That is, the pair of elastic bodies 210 and the pair of cases 220 may be disposed to face each other along the longitudinal direction of the worm shaft 10.

The elastic body 210 may be formed of a material having elasticity such as rubber or urethane, and the case 220 may be formed of a metal material such as steel having a relatively high hardness. The elastic body 210 is formed to support the support bearing 400 in the axial direction and the radial direction of the worm shaft 10, and the case 220 is formed to surround the outer side of the elastic body 210 of such a structure. do. That is, the elastic body 210 on the left side in FIG. 3 supports the outer circumferential surface and the end portions of the left surface of the outer ring of the support bearing 400, and the elastic body 210 on the right side in FIG. 3 has the outer circumferential surface and the right surface of the outer ring of the support bearing 400. Support the end of the.

As shown in FIG. 3, the support bearing damper 200 may be fixed such that movement in the axial direction of the worm shaft 10 is not permitted. For example, as illustrated in FIG. 3, the support bearing damper 200 is tightened to be screwed to the housing 40 and the engaging jaw 43 formed on the inner surface of the housing 40 into which the worm shaft 10 is inserted. It may be supported by the nut 250.

Meanwhile, referring to FIG. 2, a wrinkle protrusion 211 may be formed on an inner circumferential surface of the elastic body 210 in contact with the support bearing 400. By forming the corrugated protrusion 211, manufacturing tolerances can be absorbed and assembly of the support bearing 400 is facilitated.

Referring to FIG. 4, the elastic body 210 may include a tail portion 213 protruding from a portion 212 supporting the side surface of the support bearing 400. At this time, the tail portion 213 is formed in a state spaced apart from the side of the support bearing 400. For example, as shown in FIG. 4, the tail portion 213 may be formed to be thinner than the portion 212 supporting the side surface of the support bearing 400, so that the tail portion 213 may be spaced apart from the side surface of the support bearing 400. have.

In this case, as shown in FIG. 4, the case 220 may be formed to support the outer surface of the tail portion 213 of the elastic body 210. That is, the inner end 221 of the case 220 is bent toward the support bearing 400 to contact the outer surface of the tail 213 of the elastic body 210 to support the tail 213.

As such, when the elastic body 210 includes the tail portion 213 spaced apart from the side of the support bearing 400, the axial movement of the worm shaft 10 and the movement of the support bearing 400 are relatively large. Complementary damping may be achieved by the tail 213 of the elastic body 210. That is, the damping effect can be improved by stepwise damping by the portion 212 and the tail portion 213 supporting the side of the support bearing 400 of the elastic body 210.

Meanwhile, according to another exemplary embodiment of the present invention, the support bearing damper 200 may support the support bearing 400 elastically when the axial movement of the worm shaft 10 becomes greater than or equal to a predetermined value. The auxiliary elastic body 230 may be further disposed on both sides of the support bearing 400 in a state spaced apart from the side of the 400. That is, when the amount of movement of the worm shaft 10 and the amount of movement of the support bearing 400 moving therewith is not large, the auxiliary elastic body 230 does not come into contact with the side surface of the support bearing 400 and does not have a damping action. When the amount of movement of the worm shaft 10 and the support bearing 4000 is greater than or equal to a preset value and contacts the side surface of the support bearing 400, the worm shaft 10 and the support bearing 4000 are compressed and have a damping action. When the primary damping is made by the elastic body 210 and the axial displacement of the worm shaft 10 is greater, the additional damping action is performed by the auxiliary elastic body 230 to improve the overall damping characteristics.

In this case, the auxiliary elastic body 230 may be formed to have a stiffness greater than that of the elastic body 210. Accordingly, when a relatively small shock is generated, the shock is absorbed by the elastic body 210, and when a relatively large shock is generated and the axial displacement of the worm shaft 10 is large, the auxiliary elastic body 230 is used. Since shock absorption can be made, effective damping can be achieved depending on the magnitude of the impact.

In this case, as shown in FIG. 5, the case 220 may be formed to accommodate the auxiliary elastic body 230. That is, the auxiliary elastic body 230 may be disposed in the space between the case 220 and the side surface of the support bearing 400.

As shown in FIG. 5, the auxiliary elastic body 230 may be implemented in the form of an elastic ring formed of a material having elasticity such as rubber or urethane. On the other hand, although not shown in the drawings, the auxiliary elastic body 230 may be implemented with a spring washer, a plate spring, etc., which may provide a damping force in the axial direction of the worm shaft 10.

According to an embodiment of the present invention, the tilt bearing assembly is disposed on the side away from the motor 20 around the worm gear 11 of the portion of the worm shaft 10 is fastened to the worm shaft 10 (tilt bearing assembly) ) 100.

On the other hand, a tilting mechanism 300 is applied to apply the force to the tilt bearing assembly 100 so that the worm shaft 10 is tilted in the direction pushed toward the worm wheel 3.

The tilt bearing assembly 100 and the tilting mechanism 300 reduce the bite rate according to the machining precision of the engagement portion of the worm shaft 10 and the worm wheel 3, and increase and decrease the backlash due to wear. It performs the function of suppressing the occurrence of noise.

As shown in FIGS. 3 and 6, the tilt bearing assembly 100 and the tilting mechanism 300 may be installed at one end of the worm shaft 10 far from the motor 20, and the worm shaft It is configured to support the rotation of (10) and push the end of the worm shaft (10) in the direction of the worm wheel (3). Accordingly, the worm shaft 10 may be more firmly engaged with the worm wheel 3.

A tilt bearing 110 is disposed around the worm shaft 10. That is, the worm shaft 10 is inserted into the through hole of the tilt bearing 110 in a sliding fitting manner to allow axial movement in the left and right directions.

The bearing case 120 receives the tilt bearing 110. That is, the tilt bearing 110 is inserted into the bearing case 120 so that the bearing case 120 surrounds the outer circumferential surface of the tilt bearing 110.

The bearing case 120 may be installed with its one end caught by the catching jaw 41 of the housing 40, and the other end of the bearing case 120 may have an adjuster ring 130 and an adjuster. Supported by an adapter plug 140. The bearing case 120 is supported in the direction in which the motor 20 is located by the adjuster ring 130 and the adjuster plug 140. That is, the adjuster plug 140 is disposed outside the bearing case 120, and the adjuster plug 140 supports the outer end of the adjuster ring 130 along the axial direction of the worm shaft 10. It may be fastened to the housing 40 by screwing to adjust the position. That is, by adjusting the position by rotating the adjuster plug 140, it is possible to adjust the position of the adjuster ring 130, thereby pushing the tilt bearing 110. At this time, the locking jaw 121 is formed on the inner circumferential surface of the bearing case 120 and the tilt bearing 110 is supported by the locking jaw 121.

The adjuster ring 130 may be formed of an elastic body such as rubber. Since the adjuster ring 130 is formed of an elastic body, noise may be effectively prevented.

A damping ring 150 surrounds the outer circumferential surface of the bearing case 120. The damping ring 150 may be formed of a material having elasticity such as rubber or urethane. Since the damping ring 150 having elasticity surrounds the outer circumferential surface of the bearing case 120, noise can be effectively prevented and a damping effect can be obtained when there is a displacement or deformation of the bearing case 120.

8 and 9, the bearing case 120 may be formed to have a substantially ring shape, and the outer circumferential surface of the bearing case 120 is provided with a depression 122 formed along the circumferential direction. As shown in FIG. 3, the damping ring 150 is inserted into the depression 122 of the bearing case 120.

In this case, referring to FIG. 8, a plurality of locking jaws 121 may be formed along the inner circumferential surface of the bearing case 120 in a rib shape. Accordingly, the tilt bearing 110 can be easily assembled.

On the other hand, as shown in Figure 8, the bearing case 120 is provided with a cutout 125, it can be formed to more smoothly shrink in the radial direction. Accordingly, since the bearing case 120 may be installed in a state in which the bearing case 120 is pressed more smoothly by the damping ring 150, the damping effect may be enhanced.

In addition, as illustrated in FIG. 8, a slot 126 may be formed on the inner circumferential surface of the bearing case 120. The slot 126 may be formed along the axial direction of the worm shaft 10 and may be formed in one or a plurality. Since the slot 126 is formed on the inner circumferential surface of the bearing case 120, the tilt bearing 110 and the worm shaft 10 may move more smoothly in the vertical direction.

Meanwhile, referring to FIG. 9, a plurality of protrusions 152 may be formed along the circumferential direction on the outer circumferential surface of the damping ring 150. As the protrusion 152 is formed on the outer circumferential surface of the damping ring 150, the assembly and adjustment of the tilt bearing 110 can be facilitated and the manufacturing tolerances of the related components can be absorbed.

On the other hand, the tilting mechanism 300 exerts a force on the tilt bearing assembly 100 such that the worm shaft 10 is tilted in the direction pushed toward the worm wheel 3.

First, a tilt plug 360 for pressing the outer end of the tilt bearing 110 in the direction of the worm wheel 3 is provided. As shown in FIG. 3, the tilt plug 360 may be formed to have a substantially rod shape and may be arranged in a direction perpendicular to the axial direction of the worm shaft 10 so that an end thereof is disposed on an outer circumferential surface of the tilt bearing 110. The worm shaft 10 is disposed to be in contact with the worm shaft 10 so as to push the worm shaft 10 toward the worm wheel 3 by the movement thereof.

The support cam 370 is disposed to contact the tilt plug 360. The support cam 370 is disposed to be movable along the axial direction of the worm shaft 10 in a state of supporting the tilt plug 360. At this time, the tilt plug 360 and the support cam 370 have a tilt plug 360 perpendicular to the axial direction of the worm shaft 10 in response to the axial movement of the worm shaft 10 of the support cam 370. In order to move in the direction, they are connected to each other by cam structures. For example, the support cam 370 may be provided with an inclined surface 371 formed to be inclined with respect to the axial direction of the worm shaft 10, and the tilt plug 360 may include an inclined surface 371 of the support cam 370. An inclined surface 361 may be provided to be in surface contact, and the support cam 370 may support the tilt plug 360 while the two inclined surfaces 361 and 371 are in surface contact.

On the other hand, the elastic member 380 provides an elastic force that pushes the support cam 370 in the axial direction of the worm shaft 10. The elastic member 380 elastically supports the support cam 370 such that the support cam 370 exerts an elastic force on the support cam 370 such that the support cam 370 moves in the direction in which the tilt plug 360 is pushed toward the tilt bearing 110. I support it. The tilt plug 360 is disposed to contact the support cam 370 and is pushed toward the tilt bearing assembly 100 by the movement of the support cam 370 to tilt the tilt bearing assembly 100 in the direction of the worm wheel 3. . In other words, in FIGS. 3 and 4, the elastic member 380 provides an elastic force that pushes the support cam 370 toward the motor 20. The elastic member 380 may be formed of any member capable of providing elastic force, such as a coil spring.

The elastic member 380 is supported by a screw 390 capable of adjusting the position of the worm shaft 10 in the axial direction to elastically support the support cam 170. For example, the elastic member 380 is supported toward the support cam 370 by a screw 390 fastened to the housing 40. At this time, the elastic member 380 is disposed in a slightly compressed state to provide an elastic force to the support cam 370.

On the other hand, the housing 40 is formed to have a space in which the tilt plug 360, the support cam 370, the elastic member 380, and the screw 390 can be inserted and moved.

8 and 9, the bearing case 120 is provided with a protrusion 123 protruding outward from the bottom surface forming the depression 122 of the outer circumferential surface, and the protrusion 123 faces toward the center. An insertion hole 124 is formed, and a through hole 151 through which the protrusion 123 is inserted is formed in the damping ring 150. In addition, the tilt plug 360 may be inserted into the insertion hole 124 so that the tilt plug 360 may contact the outer circumferential surface of the tilt bearing 110 and move the tilt bearing 110 toward the worm wheel 3 by the movement thereof. Can push

Since the tilt bearing 110 surrounding the worm shaft 10 is pushed in the direction of the worm wheel 3 by the structure providing the tilting force, the worm gear 11 or the worm of the worm shaft 10 is maintained. Even when the wear of the wheel 3 progresses, the reduction of the bite rate, the increase of the back lash, and the occurrence of noise due to this can be suppressed.

On the other hand, due to the impact and reaction force transmitted from the worm wheel 3, the worm shaft 10 moves away from the worm wheel 3 (i.e., in the opposite direction to the direction in which the tilting force acts), thereby causing the backlash. In order to suppress the increase and the occurrence of noise, it is possible to limit the movement of the tilt plug 360 in the reverse direction (ie, opposite to the direction in which the tilting force acts). To this end, as shown in the drawings, the tilt plug 360 and the support cam 370 are disposed to cross at right angles to each other, and the inclined surfaces 361 and 371 of the tilt plug 360 and the support cam 370 are acute from each other. It may have a wedge structure forming a.

While the present invention has been particularly shown and described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, And all changes and modifications to the scope of the invention.

1: steering shaft 3: worm wheel
10: worm shaft 11: worm gear
20: motor 21: output shaft
30: motor coupling 31: first member
33: second member 35: connecting member
100: tilt bearing assembly 110: tilt bearing
120: bearing case 130: adjuster ring
140: adjuster plug 150: damping ring
300: tilting mechanism 360: tilt plug
370: support cam 380: elastic member
390: screw 400: support bearing
200: support bearing damper 210: elastic body
220: case 230: auxiliary elastic body

Claims (22)

delete motor,
A worm shaft having a worm gear and connected to the output shaft to integrally rotate with the output shaft of the motor;
Worm wheel coupled to the steering shaft and meshed with the worm gear,
A support bearing of the worm shaft, which is disposed near the motor with respect to the worm gear and fastened to the worm shaft, and
A support bearing damper elastically supporting the support bearing to provide a damping force to the support bearing;
The support bearing damper is
An elastic body elastically supporting the support bearing in the axial direction and the radial direction of the worm shaft, and
And a case formed to surround the axial and radial outer surfaces of the elastic body. 3. The method of claim 2,
The elastic body and the case are electrically powered steering device which is provided in a pair separated respectively along the longitudinal direction of the worm shaft. 3. The method of claim 2,
The support bearing damper is supported by a locking jaw formed in the housing into which the worm shaft is inserted and a tightening nut screwed to the housing. 3. The method of claim 2,
An electric power steering device having wrinkled protrusions formed on an inner circumferential surface of the elastic body in contact with the support bearing. 3. The method of claim 2,
The elastic body is an electric power steering apparatus including a tail formed to protrude from a portion supporting the side of the support bearing spaced apart from the side of the support bearing. The method of claim 6,
The case is an electric power steering device formed to support the outer surface of the tail. 3. The method of claim 2,
The support bearing dampers are respectively disposed on both sides of the support bearing in a state spaced apart from the side of the support bearing so as to elastically support the support bearing when the axial movement of the worm shaft becomes equal to or greater than a preset value. An electric power steering device further comprising an auxiliary elastic body. 9. The method of claim 8,
And the auxiliary elastic body has a greater stiffness than the elastic body. 9. The method of claim 8,
The case is an electric power steering device formed to receive the auxiliary elastic body. 9. The method of claim 8,
The auxiliary elastic body is a rubber ring, a spring washer, or a plate spring. motor,
A worm shaft having a worm gear and connected to the output shaft to integrally rotate with the output shaft of the motor;
Worm wheel coupled to the steering shaft and meshed with the worm gear,
A support bearing of the worm shaft, the support bearing being disposed close to the motor with respect to the worm gear and fastened to the worm shaft;
A support bearing damper elastically supporting the support bearing to provide a damping force to the support bearing;
A tilt bearing assembly disposed on a side of the worm shaft that is far from the motor with respect to the worm gear and fastened to the worm shaft; and
A tilting mechanism for applying a force to the tilt bearing assembly such that the worm shaft is tilted in a direction pushing toward the worm wheel,
The tilting mechanism is
Support cam having an inclined surface,
An elastic member for providing an elastic force for pushing the support cam in an axial direction of the worm shaft, and
And a tilt plug disposed to contact the support cam and to be pushed toward the tilt bearing assembly by the movement of the support cam to press the tilt bearing assembly to tilt in the worm wheel direction. The method of claim 12,
And the elastic member is supported by a screw which is adjustable in the worm shaft axial direction so as to elastically support the support cam. The method of claim 12,
The tilt bearing assembly
A tilt bearing disposed around the worm shaft,
A bearing case accommodating the tilt bearing, and
An electric power steering apparatus including a damping ring formed to surround an outer circumferential surface of the bearing case and formed of an elastic material. The method of claim 14,
The outer circumferential surface of the bearing case is provided with a depression formed along the circumferential direction,
The damping ring is inserted into the recessed electric power steering apparatus. The method of claim 14,
The bearing case has an electric power steering device having a cutout to facilitate the contraction in the radial direction. The method of claim 14,
The tilt bearing assembly further comprises an adjuster ring and an adjuster plug for supporting the bearing case in the direction of the motor. The method of claim 17,
The adjuster ring is an electric power steering device formed of a material having elasticity. The method of claim 14,
The inner circumferential surface of the bearing case is an electric power steering device having a slot formed along the axial direction of the worm shaft. delete delete The method of claim 14,
Through holes are formed in the damping ring,
The bearing case is provided with a protrusion inserted into the through hole and the insertion hole is formed,
The tilt bearing is assembled to the inner circumferential surface of the bearing case and the tilt plug is inserted into the insertion hole is in contact with the outer peripheral surface of the tilt bearing electric power steering apparatus.

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