KR20100102347A - Reducer of electronic power steering apparatus - Google Patents

Reducer of electronic power steering apparatus Download PDF

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Publication number
KR20100102347A
KR20100102347A KR1020090020678A KR20090020678A KR20100102347A KR 20100102347 A KR20100102347 A KR 20100102347A KR 1020090020678 A KR1020090020678 A KR 1020090020678A KR 20090020678 A KR20090020678 A KR 20090020678A KR 20100102347 A KR20100102347 A KR 20100102347A
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KR
South Korea
Prior art keywords
worm
worm shaft
shaft
bearing holder
bearing
Prior art date
Application number
KR1020090020678A
Other languages
Korean (ko)
Other versions
KR101246933B1 (en
Inventor
송준규
Original Assignee
주식회사 만도
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 주식회사 만도 filed Critical 주식회사 만도
Priority to KR1020090020678A priority Critical patent/KR101246933B1/en
Publication of KR20100102347A publication Critical patent/KR20100102347A/en
Application granted granted Critical
Publication of KR101246933B1 publication Critical patent/KR101246933B1/en

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62D—MOTOR VEHICLES; TRAILERS
    • B62D3/00—Steering gears
    • B62D3/02—Steering gears mechanical
    • B62D3/04—Steering gears mechanical of worm type
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62D—MOTOR VEHICLES; TRAILERS
    • B62D5/00—Power-assisted or power-driven steering
    • B62D5/04—Power-assisted or power-driven steering electrical, e.g. using an electric servo-motor connected to, or forming part of, the steering gear
    • B62D5/0421—Electric motor acting on or near steering gear
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H55/00—Elements with teeth or friction surfaces for conveying motion; Worms, pulleys or sheaves for gearing mechanisms
    • F16H55/02—Toothed members; Worms
    • F16H55/22—Toothed members; Worms for transmissions with crossing shafts, especially worms, worm-gears
    • F16H55/24—Special devices for taking up backlash
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60Y—INDEXING SCHEME RELATING TO ASPECTS CROSS-CUTTING VEHICLE TECHNOLOGY
    • B60Y2306/00—Other features of vehicle sub-units
    • B60Y2306/09—Reducing noise
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H57/00—General details of gearing
    • F16H57/02—Gearboxes; Mounting gearing therein
    • F16H57/021—Shaft support structures, e.g. partition walls, bearing eyes, casing walls or covers with bearings
    • F16H2057/0213—Support of worm gear shafts

Abstract

PURPOSE: A reducer of an electronic power steering apparatus is provided to accurately assist the steering-wheel operating of a driver through the prevention of the gap due to the abrasion of a worm and a worm hole, the restriction of the rattle noise by backlash, the minimization of the gap change depending on the change of the torque. CONSTITUTION: A reducer of an electronic power steering apparatus comprises a worm shaft bearing(257), a bearing holder(310), and an elastic support(320). The worm shaft bearing supports the end of a worm shaft(254) in which a worm(152) engaging with a worm wheel(156) is formed. The bearing holder is connected to the outer wheel(270) of the worm shaft bearing. The bearing holder comprises a pivoting member(313) extended in the axis direction of the steering shaft from the center of the worm shaft. The elastic support is fixed to the pivoting member of the bearing holder, wherein one side is supported on the bearing holder and the other side is supported on a gear housing. The elastic support applies a rotating force centered on the pivoting member so that the end of the worm shaft makes tight contact with the worm wheel.

Description

Reducer of Electronic Power Steering Apparatus

The present invention relates to a speed reducer of an electric power assisted steering device. More specifically, in the reducer of the electric power assisted steering device, it prevents the play caused by the wear of the worm and the worm wheel, prevents the occurrence of the rattle noise by the backlash, and minimizes the amount of play change caused by the change of the rotation torque. The present invention relates to a speed reducer of an electric power assist steering device capable of accurately assisting wheel operation force.

1 is a configuration diagram of a conventional electric power assisted steering device, as shown in FIG. 1, the electric power assisted steering device 100 includes a steering system 130 and steering which extends from the steering wheel 102 to both wheels 126. And an auxiliary power mechanism 140 that provides steering assistance power to the system 130.

Steering system 130 is a steering shaft 106, one side is connected to the steering wheel 102 to rotate together with the steering wheel 102 and the other side is connected to the pinion shaft 108 via a pair of universal joint 104 It is configured to include). In addition, the pinion shaft 108 is connected to the rack bar 112 through the rack-pinion mechanism unit 110, and both ends of the rack bar 112 are connected to the wheels 126 of the vehicle through the tie rods 122 and the knuckle arm 124. )

The auxiliary power mechanism 140 senses torque applied to the steering wheel 102 by the driver and outputs an electrical signal proportional to the detected torque based on the electrical signal transmitted from the torque sensor 142 and the torque sensor 142. The steering shaft 106 controls the electronic control device 144 that generates the control signal, the motor 146 that generates auxiliary power based on the control signal transmitted from the electronic control device 144, and the auxiliary power generated by the motor 146. It comprises a reducer 150 having a worm 152 and a worm wheel 156 for delivery to.

Accordingly, in the electric power assist steering device, torque generated by the rotation of the steering wheel 102 is transmitted to the rack bar 112 via the rack-pinion mechanism unit 110, and the assist power generated in the motor 146 according to the generated torque. It is configured to be delivered to the rack bar 112.

That is, the torque generated by the rotation of the steering wheel 102 and the auxiliary power generated by the motor 146 are combined to move the rack bar 112 in the axial direction.

2 is a cross-sectional view showing a reducer of a conventional electric power assisted steering device. As shown in FIG. 2, the reducer 150 includes a worm shaft 254 having a worm 152 formed thereon, and a worm shaft bearing at both ends of the worm shaft 254. 257 are respectively installed to support the worm shaft 254, the plug bolt 210 is damped coupler 240 and the worm shaft bearing in order to prevent the worm shaft bearing 257 is spaced in the axial direction of the worm shaft 254 ( 257, and the plug bolt 210 is fixed by the plug nut 220.

The worm shaft 254 has a structure in which the worm shaft 254 is rotated by the driving of the motor 146 by connecting the motor 146 and the damping coupler 240 as a medium.

And the worm wheel 156 is provided on one side of the outer diameter of the worm 152 so that the worm 152 formed on the worm shaft 254, the worm wheel 156 is a rotational force of the steering wheel 102 that the driver can operate Is mounted on the steering shaft 106 to transmit the rotational force of the worm shaft 254 by the drive of the motor 146 is a structure that is transmitted to the steering shaft 106.

The gear housing 260 includes a motor 146 which is provided with a worm 152, a worm wheel 156, and the like, and provides a driving force to the worm shaft 254 on one side of the gear housing 260. Motor 146 is coupled to bolt 250 by motor cover 230.

The worm shaft bearing 257 has a ball 258 coupled between the inner ring 280 and the outer ring 270 to support rotation of the worm shaft 254 connected to the motor 150 at the end of the gear housing 260. do.

The speed reducer of the electric power assisted steering device having such a structure controls the driving of the motor by an electronic control device provided in the vehicle according to the vehicle driving conditions, and the rotational force of the worm shaft by the driving of the motor controls the steering wheel of the driver. In addition to the rotational force is transmitted to the steering shaft, so that the steering operation state of the driver can be kept smooth and stable.

However, the reducer of the conventional electric power assisted steering device has a problem in that the worm and the worm wheel rotated by the driving of the motor cause the rattle noise due to play and backlash caused by wear when the worm and the worm wheel are durable.

In addition, this has a problem in that it is not possible to accurately provide a steering assistance force to assist the steering wheel operation force of the driver.

In order to solve the above problems, the present invention, in the reducer of the electric power assisted steering device, to prevent the play by the wear of the worm and the worm wheel and to prevent the generation of rattle noise by the backlash, the amount of play change according to the change of the rotation torque The purpose of the present invention is to provide a speed reducer of an electric power assisted steering apparatus that can accurately assist the driver's steering wheel operating force.

In order to achieve this object, the present invention includes a worm shaft bearing for supporting the opposite end of the motor coupling portion of the worm shaft is formed with a worm meshing with the worm wheel; A bearing holder press-coupled to an outer ring of the worm shaft bearing and having a pivot member extending from a center of the worm shaft in an axial direction of a steering shaft; And an elastic support coupled to and fixed to the pivot member of the bearing holder, one side of which is supported by the bearing holder and the other of which is supported by a gear housing, to apply rotational force to the axis of the pivot member so as to closely contact the worm shaft end in the worm wheel direction. It provides a reducer of the electric power assist steering device, characterized in that comprising a.

According to the present invention, in the speed reducer of the electric power assisted steering device, it prevents the play caused by the wear of the worm and the worm wheel, prevents the generation of rattle noise by the backlash, and minimizes the amount of play change caused by the change of rotation torque, the driver's steering There is an effect that can accurately assist the wheel operating force.

Hereinafter, some embodiments of the present invention will be described in detail through exemplary drawings. In adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are assigned to the same components as much as possible even though they are shown in different drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

In addition, in describing the component of this invention, terms, such as 1st, 2nd, A, B, (a), (b), can be used. These terms are only for distinguishing the components from other components, and the nature, order or order of the components are not limited by the terms. If a component is described as being "connected", "coupled" or "connected" to another component, that component may be directly connected to or connected to that other component, but there may be another configuration between each component. It is to be understood that the elements may be "connected", "coupled" or "connected".

Figure 3a is a perspective view showing a part of the reducer of the electric power assisted steering apparatus according to an embodiment of the present invention, Figure 3b is an exploded perspective view showing a part of the reducer of the electric power assisted steering apparatus according to an embodiment of the present invention, Figure 4 is Figure 3a is a view of the reducer of the electric power assisted steering apparatus shown in the worm shaft direction.

As shown in these drawings, the speed reducer 300 of the electric power assisted steering apparatus according to the embodiment of the present invention includes a motor 146 of the worm shaft 254 in which a worm 152 engaged with the worm wheel 156 is formed. A worm shaft bearing 257 for supporting the opposite end of the engaging portion; A bearing holder 310 is press-fitted to the outer ring 270 of the worm shaft bearing 257 and has a pivot member 313 extending from the center of the worm shaft 254 in the axial direction of the steering shaft 106. ; And fixedly coupled to the pivot member 313 of the bearing holder 310, one side of which is supported by the bearing holder 310 and the other of which is supported by a gear housing, and the end of the worm shaft 254 is directed toward the worm wheel 156. It is configured to include; an elastic support 320 for applying a rotational force to the pivot member 313 to the axis to be in close contact with.

The speed reducer 300 of the electric power assisted steering apparatus according to the present invention has a structure in which the bearing support 310 is pivoted so that the elastic support 320 supports the worm shaft 254 in the direction of the worm wheel 156 in the gear housing. In this case, the backlash is eliminated when the worm 152 and the worm wheel 156 rotate, and the rattle noise is prevented.

The reduction gear assists the driver's steering force by rotating the steering shaft 106 while the worm 152 and the worm wheel 156 are interlocked by the driving force of the motor 146. The worm shaft bearing 257 is fastened to both ends of the worm shaft 254 interlocked with the shaft to support rotation of the worm shaft 254, and the worm wheel 156 and the worm 152 interlocked with the steering shaft 106 are mounted on the gear housing. It is built in.

On the other hand, in the opposite direction of the motor 146, the worm shaft bearing 257, in which the ball 258 is coupled between the inner ring 280 and the outer ring 270, supports the rotation of the worm shaft 254 at the end of the gear housing. The bearing holder 310 is inserted into the outer ring 270 of the worm shaft bearing 257, and the outer side of the bearing holder 310 has an worm wheel 254 at the end of the worm shaft 254 in which the elastic support 320 is coupled with the bearing holder 310. It is supported in the direction 156 to prevent backlash generated in the worm 152 and the worm wheel 156.

The worm shaft bearing 257 is mounted between the bearing holder 310 and the worm shaft 254 and supports the rotation of the worm shaft 254 at both ends of the worm shaft 254, wherein the ball 258 has an inner ring 280 and an outer ring of the bearing. Rotation between 270 reduces the rotational resistance of the worm shaft (254).

When the rotational durability of the worm shaft 254 progresses, noise and backlash are generated due to the play caused by the wear of the worm 152 and the worm wheel 156. To compensate for the play, the opposite side of the motor coupling part of the worm shaft 254 is provided. An elastic support 320 is mounted to push the worm shaft 254 toward the worm wheel 156 to remove the play.

The bearing holder 310 is formed of an engineering plastic such as steel or acetal resin having rigidity, and has an worm shaft 254 end portion penetrated at the center thereof to be coupled to the worm shaft bearing 257. The outer ring 270 of the worm shaft bearing 257 is provided. It is press-fitted while maintaining a constant clearance while wrapping the worm shaft bearing 257 to prevent the departure.

In addition, the bearing holder 310 is provided with a pivot member 313 extending in the axial direction of the steering shaft 106 from the center of the worm shaft 254 in a direction parallel to the worm shaft 254, the elastic support 320 By pivoting the pivot member 313 to the axis by the rotation, as well as the coupling direction of the worm 152 and the worm wheel 156, the coupling direction and the predetermined angle of the worm 152 and the worm wheel 156 The force can be applied in the direction of formation.

Therefore, premature wear of the gear generated when simply pushing the worm shaft 254 only in the coupling direction of the worm 152 and the worm wheel 156, and occurs in the worm shaft 254 when driving the motor 146 in the forward and reverse directions. Impact noise and rattle noise can be prevented.

In addition, the bearing holder 310 is provided with a pivot member 313 extending in the axial direction of the steering shaft 106 perpendicular to the worm shaft 254 from the center of the worm shaft 254, the elastic support 320 is It is fixed to the pivot member 313 so that the bearing holder 310 is supported.

The pivot member 313 is pivotally fixed to the gear housing so that the bearing member 310 rotates about the pivot member 313 so that the pivoting member 313 rotates. Is formed, and the shaft member (not shown) is inserted into the housing coupling hole 315 so as to be fixed to the gear housing to rotate.

Therefore, the worm shaft 254 coupled to the bearing holder 310 is in a pivoting motion in which the worm wheel 156 is in close contact with the elastic support 320 coupled to the outside of the bearing holder 310.

In this case, the elastic support 320 may have a torsion spring wound at one end thereof to be supported by the bearing holder 310 and the other end thereof to be supported by the gear housing.

According to the present invention having such a shape and structure, in the reduction gear of the electric power assist steering device, it prevents the play caused by the wear of the worm and the worm wheel, and prevents the generation of rattle noise by the backlash, the amount of play change according to the change of the rotation torque By minimizing this, it is possible to accurately assist the driver's steering wheel operating force.

In the above description, all elements constituting the embodiments of the present invention are described as being combined or operating in combination, but the present invention is not necessarily limited to the embodiments. In other words, within the scope of the present invention, all of the components may be selectively operated in combination with one or more.

In addition, the terms "comprise", "comprise" or "having" described above mean that the corresponding component may be included, unless otherwise stated, and thus excludes other components. It should be construed that it may further include other components instead.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention but to describe the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

1 is a block diagram of a conventional electric power assisted steering device;

2 is a cross-sectional view showing a reducer of a conventional electric power assisted steering device;

Figure 3a is a perspective view showing a part of the reducer of the electric power assisted steering apparatus according to the embodiment of the present invention;

Figure 3b is an exploded perspective view showing a part of the reducer of the electric power assisted steering apparatus according to the embodiment of the present invention;

4 is a view of the reducer of the electric power assisted steering apparatus illustrated in FIG. 3A as viewed in the worm shaft direction.

<Description of the symbols for the main parts of the drawings>

146: motor 152: worm

156: worm wheel 254: worm shaft

257: worm shaft bearing 258: ball

270: outer ring 280: inner ring

310: bearing holder 313: pivot member

315: housing coupling hole 320: elastic support

Claims (3)

A worm shaft bearing supporting an opposite end of the motor coupling portion of the worm shaft on which a worm meshing with the worm wheel is formed; A bearing holder press-coupled to an outer ring of the worm shaft bearing and having a pivot member extending from a center of the worm shaft in an axial direction of a steering shaft; And An elastic support coupled to and fixed to the pivot member of the bearing holder, one side of which is supported by the bearing holder and the other side of which is supported by a gear housing to apply rotational force to the axis of the pivot member to closely contact the worm shaft end in the worm wheel direction; Reducer of the electric power assisted steering device, characterized in that it comprises a. The method of claim 1, The elastic support is a reducer of the electric power assist steering device, characterized in that the one end is supported by the bearing holder, the other end is a torsion spring wound so as to be supported by the gear housing. The method of claim 1, The pivot member of the bearing holder is a reduction gear of the electric power assist steering device, characterized in that the housing coupling hole is formed in the center so as to be fixed to the gear housing to rotate through the shaft member.
KR1020090020678A 2009-03-11 2009-03-11 Reducer of Electronic Power Steering Apparatus KR101246933B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR1020090020678A KR101246933B1 (en) 2009-03-11 2009-03-11 Reducer of Electronic Power Steering Apparatus

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Application Number Priority Date Filing Date Title
KR1020090020678A KR101246933B1 (en) 2009-03-11 2009-03-11 Reducer of Electronic Power Steering Apparatus

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KR20100102347A true KR20100102347A (en) 2010-09-24
KR101246933B1 KR101246933B1 (en) 2013-03-25

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2016012181A1 (en) * 2014-07-22 2016-01-28 Thyssenkrupp Presta Ag Electromechanical power steering system
CN108488369A (en) * 2018-03-27 2018-09-04 浙江吉利控股集团有限公司 The adjustable steering column in gap and automobile
DE102017218897A1 (en) * 2017-10-23 2019-04-25 Thyssenkrupp Ag Steering column for a motor vehicle
CN112407024A (en) * 2020-10-27 2021-02-26 宁波拓普集团股份有限公司 Steering column worm axial clearance compensation method
KR20220089802A (en) * 2020-12-21 2022-06-29 계양전기 주식회사 Actuator
US11492034B2 (en) * 2017-08-04 2022-11-08 Thyssenkrupp Presta Ag Reduction of play of a worm gear of an electromechanical power steering system by means of a bimetal spring

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4052218B2 (en) * 2003-09-30 2008-02-27 株式会社ジェイテクト Electric power steering device
KR100621347B1 (en) 2005-09-20 2006-09-07 주식회사 만도 Electric power steering apparatus for automotive vehicle

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2016012181A1 (en) * 2014-07-22 2016-01-28 Thyssenkrupp Presta Ag Electromechanical power steering system
CN106536327A (en) * 2014-07-22 2017-03-22 蒂森克虏伯普利斯坦股份公司 Electromechanical power steering system
CN106536327B (en) * 2014-07-22 2019-01-11 蒂森克虏伯普利斯坦股份公司 Electromechanical power steering system
US10252742B2 (en) 2014-07-22 2019-04-09 Thyssenkrupp Presta Ag Electromechanical power steering system
US11492034B2 (en) * 2017-08-04 2022-11-08 Thyssenkrupp Presta Ag Reduction of play of a worm gear of an electromechanical power steering system by means of a bimetal spring
DE102017218897A1 (en) * 2017-10-23 2019-04-25 Thyssenkrupp Ag Steering column for a motor vehicle
EP3700801B1 (en) * 2017-10-23 2022-03-30 thyssenkrupp Presta AG Steering column for a motor vehicle
US11655889B2 (en) 2017-10-23 2023-05-23 Thyssenkrupp Presta Ag Steering column for a motor vehicle
CN108488369A (en) * 2018-03-27 2018-09-04 浙江吉利控股集团有限公司 The adjustable steering column in gap and automobile
CN108488369B (en) * 2018-03-27 2021-01-05 浙江吉利控股集团有限公司 Steering column with adjustable gap and automobile
CN112407024A (en) * 2020-10-27 2021-02-26 宁波拓普集团股份有限公司 Steering column worm axial clearance compensation method
KR20220089802A (en) * 2020-12-21 2022-06-29 계양전기 주식회사 Actuator

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