阅读说明：本技术 一种转向系统涡轮蜗杆减速机构间隙补偿机构 (Steering system turbine worm reduction gears clearance compensation mechanism ) 是由 汪朋 唐学东 柳强 胡俊生 李海亮 于 2021-08-17 设计创作，主要内容包括：本发明涉及一种转向系统涡轮蜗杆减速机构间隙补偿机构,包括输出轴、滑套、涡轮及螺旋弹簧；输出轴包括输出轴本体,在输出轴本体用于安装涡轮的位置的表面设置有多个轴向滑槽,相邻两个轴向滑槽之间形成间隔筋,在输出轴上靠近大端侧设置有法兰,在法兰与轴向滑槽相对的表面设置有法兰凹槽；滑套套于输出轴的轴向滑槽处,涡轮套于滑套上；在涡轮靠近法兰的一侧设置有涡轮凹槽,螺旋弹簧设置于涡轮凹槽与法兰凹槽之间。本技术方案通过涡轮补偿技术,在涡轮与输出轴之间通过滑套连接,在传递扭矩的同时推动涡轮移动,改变啮合点,使得补偿力的作用点位于涡轮上,从而削除涡轮磨损带来的影响。(The invention relates to a clearance compensation mechanism of a worm gear and worm speed reducing mechanism of a steering system, which comprises an output shaft, a sliding sleeve, a worm gear and a spiral spring, wherein the output shaft is connected with the sliding sleeve; the output shaft comprises an output shaft body, a plurality of axial sliding grooves are formed in the surface of the position, used for mounting the turbine, of the output shaft body, spacing ribs are formed between every two adjacent axial sliding grooves, a flange is arranged on the side, close to the large end, of the output shaft, and a flange groove is formed in the surface, opposite to the axial sliding grooves, of the flange; the sliding sleeve is sleeved at the axial sliding chute of the output shaft, and the turbine is sleeved on the sliding sleeve; a turbine groove is formed in one side, close to the flange, of the turbine, and the spiral spring is arranged between the turbine groove and the flange groove. This technical scheme passes through turbine compensation technique, is connected through the sliding sleeve between turbine and output shaft, promotes the turbine and removes when transmission moment of torsion, changes the mesh point for the action point of compensation force is located the turbine, thereby eliminates the influence that turbine wear brought.)

1. A clearance compensation mechanism of a worm gear and worm speed reducing mechanism of a steering system is characterized by comprising an output shaft, a sliding sleeve, a worm gear and a spiral spring;

the output shaft comprises an output shaft body, a plurality of axial sliding grooves are formed in the surface of the position, used for mounting the turbine, of the output shaft body, spacing ribs are formed between every two adjacent axial sliding grooves, a flange is arranged on the side, close to the large end, of the output shaft, and a flange groove is formed in the surface, opposite to the axial sliding grooves, of the flange;

the sliding sleeve is sleeved at the axial sliding groove of the output shaft, and the turbine is sleeved on the sliding sleeve;

a turbine groove is formed in one side, close to the flange, of the turbine, and the spiral spring is arranged between the turbine groove and the flange groove.

2. The clearance compensation mechanism of a turbine and worm speed reducing mechanism of a steering system according to claim 1, wherein the sliding sleeve is composed of a sliding sleeve outer ring and a sliding sleeve inner ring, the sliding sleeve inner ring is matched with the shape formed by the sliding groove and the spacing ribs of the output shaft, and the shape of the sliding sleeve outer ring is matched with the shape of the turbine inner ring.

3. The clearance compensating mechanism of a worm gear speed reducing mechanism of a steering system according to claim 2, wherein a metal needle roller and a metal ball are respectively inserted into the surface of the sliding sleeve, and the sliding sleeve is sleeved on the output shaft, and the sliding sleeve is in contact with the output shaft through the metal needle roller and the metal ball.

4. The clearance compensating mechanism of the worm gear speed reducing mechanism of the steering system according to claim 3, wherein the metal needle roller and the metal ball are arranged at intervals on the circumference of the sliding sleeve.

5. The steering system turbine worm reduction mechanism clearance compensation mechanism of claim 1, wherein the flange is of unitary construction with the output shaft body.

6. The steering system turbine worm reduction mechanism backlash compensation mechanism of claim 1, wherein the coil spring is in a compressed state after the turbine is mounted to the output shaft.

Technical Field

The invention belongs to the technical field of worm gears of steering systems, and particularly relates to a clearance compensation mechanism of a worm gear speed reducing mechanism of a steering system.

Background

With the technological progress and the pressure of environmental protection, the electronic power steering system becomes a standard for automobiles. The electronic power-assisted steering system provides power for the steering system through the motor, replaces the traditional hydraulic oil to provide power, can reduce oil pollution in the maintenance process, and is convenient to maintain. For a column power-assisted steering system, a motor is connected with a worm through a coupler, the motor drives the worm to rotate, and the worm drives a turbine to rotate. The motor torque acts on the output shaft of the pipe column through the worm gear and worm speed reducing and torque increasing mechanism. The torque output by the motor finally acts on the steering column, is superposed with the operation force of a driver and acts on the steering engine through the transmission device, and is finally converted into the force for driving the wheels to move.

Because the reduction ratio of the worm gear and worm speed reducing mechanism is large, the transmitted torque is large, and the worm gear is usually made of nylon, the tooth surface of the worm gear is inevitably worn, the meshing gap at the meshing position of the worm gear and worm becomes large after the tooth surface is worn, and the large meshing gap is the root cause of abnormal sound of a steering system.

Because the turbine tooth profile is helical, the meshing part is usually the tooth surface center position, and the tooth surface far away from the center position can not be worn because of not participating in the meshing. At present, a turbine and worm clearance compensation mechanism is generally adopted in a steering system, acting force is applied to a worm, the worm generates displacement towards a turbine, and therefore the worm is pushed to the turbine, and the clearance compensation effect is achieved.

The action principle of a turbine and worm clearance compensation mechanism which is commonly adopted at the present stage is that the small end of the worm is made into a floating form, and a spiral spring 01 is arranged at the small end of the worm and is always in a compression state to continuously provide thrust to push the worm to the turbine end, so that clearance compensation is realized.

As shown in figure 1, the acting point of the clearance compensation force F is positioned at the small end position of the worm, and the structure is simple and easy to realize. However, the worm is similar to a lever, the meshing part of the worm gear and the worm is positioned in the middle of the lever, namely the middle part of the worm, and the actual clearance compensation value at the position is only half of the displacement of the spiral spring 01 at the small end, so that the clearance compensation effect cannot be fully exerted.

In order to overcome the above problems, another compensation mode is adopted, as shown in fig. 2, the function principle is that the small end of the worm is made into a floating mode, an L-shaped thin-plate spring 02 is fixed on the worm gear casing, the bent part at the tail end of the spring extends into the worm cavity and is abutted against the small end of the worm, the pushing force is continuously provided, and the worm is pushed to the worm gear end, so that the clearance compensation is realized. The purpose of clearance compensation is achieved by applying a force to the small end of the worm. Such as patent numbers ZL 201610852796.2, ZL 201621082539.7 and ZL 201720211613.9. Although there is a gap compensation mechanism, there is still a loose abnormal sound after a period of use.

Disclosure of Invention

The invention aims to provide a clearance compensation mechanism of a worm and gear speed reducing mechanism of a steering system, which adopts a floating worm gear mode to solve the problems that the existing clearance compensation mechanism of the worm and gear still has loose abnormal sound and the compensation effect is not ideal after the clearance compensation mechanism of the worm and gear is used for a period of time.

In order to realize the purpose, the invention is realized by the following technical scheme:

a clearance compensation mechanism of a worm gear and worm speed reducing mechanism of a steering system comprises an output shaft, a sliding sleeve, a worm gear and a spiral spring;

the output shaft comprises an output shaft body, a plurality of axial sliding grooves are formed in the surface of the position, used for mounting the turbine, of the output shaft body, spacing ribs are formed between every two adjacent axial sliding grooves, a flange is arranged on the side, close to the large end, of the output shaft, and a flange groove is formed in the surface, opposite to the axial sliding grooves, of the flange;

the sliding sleeve is sleeved at the axial sliding groove of the output shaft, and the turbine is sleeved on the sliding sleeve;

a turbine groove is formed in one side, close to the flange, of the turbine, and the spiral spring is arranged between the turbine groove and the flange groove.

Furthermore, the sliding sleeve is composed of a sliding sleeve outer ring and a sliding sleeve inner ring, the sliding sleeve inner ring is matched with the sliding groove of the output shaft and the shape formed by the spacing ribs, and the shape of the sliding sleeve outer ring is matched with the shape of the turbine inner ring.

Furthermore, after the metal roller pins and the metal balls are respectively embedded into the surface of the sliding sleeve, the sliding sleeve is sleeved on the output shaft, and the sliding sleeve is in contact with the output shaft through the metal roller pins and the metal balls.

Furthermore, the metal needle roller and the metal ball are arranged on the periphery of the sliding sleeve at intervals.

Further, the flange and the output shaft body are of an integral structure.

Further, after the turbine is mounted on the output shaft, the coil spring is in a compressed state.

The invention has the beneficial effects that:

this technical scheme passes through turbine compensation technique, compares in present worm clearance compensation mechanism, and this technique is connected through the sliding sleeve between turbine and output shaft, promotes the turbine and removes when the transmission moment of torsion for the meshing point is changed, makes the effect point of compensation force be located the turbine, thereby eliminates the influence that turbine wear and tear brought.

Drawings

FIG. 1 is a schematic diagram of a conventional spiral spring worm compensation structure;

FIG. 2 is a schematic diagram of a conventional leaf spring worm compensation structure;

FIG. 3 is a schematic view of an output shaft of the compensating mechanism of the present invention;

FIG. 4 is a cross-sectional view A-A of FIG. 3;

FIG. 5 is a side view of the sliding sleeve;

FIG. 6 is a schematic view of the sliding sleeve inlaid with metal needle rollers and metal balls;

FIG. 7 is a side view of the turbine;

FIG. 8 is a B-B cross-sectional view of the turbine;

FIG. 9 is an enlarged view at C of FIG. 8;

FIG. 10 is an assembled view of the output shaft and the sliding sleeve;

FIG. 11 is an assembled view of the output shaft, the sliding sleeve and the turbine;

FIG. 12 is a schematic view of the turbine worm clearance compensation mechanism of the present invention;

FIG. 13 is a cross-sectional view of the worm gear backlash compensation mechanism of the present invention.

Description of the reference numerals

01. The device comprises a spiral spring 02, a leaf spring 1, an output shaft 11, an output shaft body 12, a turbine mounting part 13, an axial sliding groove 14, a spacing rib 15, a flange 16, a flange groove 2, a sliding sleeve 21, a sliding sleeve inner ring 22, a sliding sleeve outer ring 3, a metal needle roller 4, a metal ball 5, a turbine 51, a turbine inner ring 52, a turbine groove 6 and a spiral spring.

Detailed Description

The technical solutions of the present invention are described in detail below by examples, and the following examples are only exemplary and can be used only for explaining and explaining the technical solutions of the present invention, but not construed as limiting the technical solutions of the present invention.

Abbreviations and key term definitions of the present technical solution

A turbine: in a common electronic power steering system, a mechanism component for reducing speed and increasing torque is matched with a worm for use. In order to ensure the transmission reliability and reduce the weight of parts, the turbine is made of nylon and glass fiber;

worm: in a common electronic power steering system, a mechanism component for reducing speed and increasing torque is used in cooperation with a turbine. The worm is typically of alloy steel.

The big end of the worm: the worm is fixed in the worm gear and worm mechanism shell, and the worm is connected with one end of the motor, usually adopting a joint ball bearing, and the bearing ensures that the worm can swing around the ball center of the ball bearing, and the end is called as the big end of the worm.

The small end of the worm: the other side of the big end of the worm is called the small end of the worm.

Steering column output shaft: an output shaft at the tail end of a steering column is fixedly connected with the turbine aiming at a common column boosting type steering system, and the motor drives the turbine to rotate through the worm, so that the speed is reduced, the torque is increased, and the torque is output.

Sliding sleeve: the invention provides a device which is assembled between an output shaft of the steering column and a turbine, can transmit force and moment in a radial direction, and cannot axially bear force or transmit moment.

The spring is a spiral spring provided by the invention, and the clearance generated by meshing of a worm and a worm wheel can be compensated through the elastic force action of the spring.

The source of thought of the technical scheme

In the conventional worm gear and worm clearance compensation mechanism, a spring is arranged at the small end of a worm and is always in a compressed state, and thrust is continuously provided in the whole life cycle to push the worm to a worm gear. The action point of the thrust is positioned at the small end of the worm, and the part generated by the clearance between the worm and the worm wheel is the meshing part of the worm wheel and the worm wheel, usually the middle part of the worm, so the clearance compensation effect is not ideal.

If the elasticity of the spring at the small end of the worm is increased, theoretically, after the worm of the worm wheel is abraded, the residual elasticity of the spring is larger, and the worm can be pushed to the worm wheel. However, the large elastic force can cause the initial abrasion of the worm gear to be intensified, and the worm gear can be rapidly abraded in the using process, so that the steering is negatively influenced.

The invention provides a clearance compensation mechanism for a turbine and a worm of a steering system, which adopts a floating turbine form, and the turbine can axially move and can stably transmit torque. Under the action of spring elasticity, the floating turbine slightly moves along the axis of the turbine, and the meshing point of the turbine and the worm slightly moves, so that the turbine and the worm are always meshed without gaps.

The invention provides a turbine and worm clearance compensation mechanism, which comprises an output shaft of a steering column, as shown in figures 3 and 4, the output shaft 1 comprises an output shaft body 11, the length, the periphery and the layout of each part of the output shaft body are basically the same as the structure of the existing output shaft, the improvement is that a plurality of axial sliding grooves 13 are processed on the periphery of the position of the output shaft for mounting a turbine, a spacing rib 14 is formed between two adjacent axial sliding grooves, the shape formed by the axial sliding grooves and the spacing rib is used for being matched with a sliding sleeve, and the sliding sleeve 2 is sleeved on the output shaft 1 and can slide along the axial direction of the output shaft. A flange 15 is arranged on the output shaft close to the large end, and a flange groove 16 is arranged on the surface of the flange opposite to the axial sliding groove.

As shown in fig. 5 and 6, the sliding sleeve 2 of the present application is composed of a sliding sleeve outer ring 22 and a sliding sleeve inner ring 21, wherein the shape of the sliding sleeve inner ring is completely consistent with the shape composed of the axial sliding groove and the spacing rib, so as to ensure that the sliding sleeve is correctly matched with the output shaft, and the sliding sleeve is installed at the position of the turbine installation part of the output shaft.

The sliding sleeve in this application is when playing the turn to, and the moment of torsion that the transmission motor produced through worm drive turbine lets the helping hand of motor and driver effect hand power coupling on the steering wheel.

In order to ensure the reliability of torque transmission, metal roller pins 3 and metal balls 4 are embedded in the surface of the sliding sleeve at intervals, and a structural form of combining the roller pins and the balls is used, so that large torque can be transmitted, and the sliding sleeve has wear resistance.

In this application, the sliding sleeve passes through metal kingpin and metal ball contact with the output shaft, and the sliding sleeve can guarantee that the worm possesses certain displacement volume in the output shaft direction.

As shown in fig. 7 to 9, the overall structure of the turbine 5 of the present application is substantially the same as that of the existing turbine, and the improvement is that the shape of the inner ring 51 of the turbine is completely consistent with that of the outer ring of the sliding sleeve, so as to ensure that the turbine 5 and the sliding sleeve 2 are correctly matched, and provide axial displacement while transmitting torque. A turbine groove 52 is provided on the side of the turbine opposite the flange of the output shaft.

As shown in fig. 10 to 13, the output shaft is first sleeved with the coil spring 6, so that one end of the coil spring enters the groove of the flange, the sliding sleeve inlaid with the metal needle roller and the metal ball is sleeved on the turbine mounting portion of the output shaft, and then the turbine is sleeved on the sliding sleeve, so that the other end of the coil spring enters the groove of the turbine, and the coil spring has a certain pressing force. In the working process, the spiral spring is always in a compressed state, and the spiral spring generates elastic force to push the turbine to generate micro displacement along the axial direction. Due to the particularity of the gear teeth of the worm wheel, the worm wheel can be always kept in close contact with the worm after moving along the axial direction, and the clearance generated by friction is eliminated.

The foregoing shows and describes the general principles and broad features of the present invention and advantages thereof. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.