CN219570797U

CN219570797U - Electric steering speed reducing mechanism with adjustable center distance between worm wheel and worm

Info

Publication number: CN219570797U
Application number: CN202320339970.9U
Authority: CN
Inventors: 吴罡; 黄伟; 李彩霞
Original assignee: Chery Automobile Co Ltd
Current assignee: Chery Automobile Co Ltd
Priority date: 2023-02-28
Filing date: 2023-02-28
Publication date: 2023-08-22
Anticipated expiration: 2033-02-28

Abstract

The utility model discloses an electric steering speed reducing mechanism with an adjustable center distance between a worm wheel and a worm, which comprises a speed reducing mechanism box body, a motor shaft, and the worm wheel and the worm which are meshed with each other, wherein the worm is arranged in the speed reducing mechanism box body through a bearing, a spring pre-tightening mechanism is arranged on the speed reducing mechanism box body corresponding to a bearing at the outer end of the worm, one end of the motor shaft is connected with the inner end of the worm through a kidney-shaped spline structure, and the bearing arranged corresponding to the inner end of the worm is a deflection bearing. The motor shaft end is designed into a waist-shaped spline, the big end bearing of the worm adopts a deflection bearing, the small end of the worm adopts a self-lubricating bushing to wrap the deep groove ball bearing at the small end of the worm, a pre-tightening spring with a specific angle is arranged outside the self-lubricating bushing, the center distance compensation range of the worm wheel and the worm is large, and the worm is stable and reliable in long-term use.

Description

Electric steering speed reducing mechanism with adjustable center distance between worm wheel and worm

Technical Field

The utility model relates to the technical field of automobile electric steering, in particular to an electric steering speed reducing mechanism with an adjustable center distance between a worm wheel and a worm.

Background

With the development of new technologies such as electric drive and electric control, the national regulations on the fuel consumption and emission of the whole vehicle are implemented, a large number of pure electric vehicles or electric hybrid vehicles are marketed, the specific gravity of the fuel vehicles is higher and higher, the electric power steering which is more energy-saving (about saving fuel by 5%) and maintenance-free (hydraulic steering requires regular or constant mileage replacement of hydraulic steering oil) is currently the main stream configuration of the vehicle. The working mechanism of the electric steering mechanism is as follows: signals of an engine, a vehicle speed, an angle, a torque sensor and the like are fed back to an ECU (electronic control Unit) controller of the whole vehicle CAN (controller area network), then the ECU controller controls a motor, and the motor drives a speed reducing mechanism to work so as to provide speed-following power assistance for the steering of the whole vehicle steering device.

The electric steering speed reducing mechanism is generally in a worm wheel and worm structure, the worm is generally in a metal material, the worm wheel meshed with the worm is generally in a nylon or nylon+glass fiber material, in order to improve the stability and reliability of the transmission gear, two ends of the worm are adopted by most factories, and a small part of factories adopt three ends of the worm, so that the meshing coincidence degree of the worm wheel and the worm is improved. The worm wheel and worm drive structure has a fixed center distance and a center distance adjustable structure design. The design of the worm wheel and worm reduction transmission mechanism with corresponding materials, coincidence ratio and grease lubrication needs to face the driving of a motor with 3-6Nm@500-4500 RPM. In this way, the problem that each manufacturer must solve is solved by coping with wear and corresponding performance degradation in long-term operation of the worm wheel and the worm. As the requirements of users on the steering quality of vehicles are higher, the adjustable center distance structure of the speed reducing mechanism has become the mainstream of the development products in the current market.

The utility model discloses a turbine worm clearance compensation mechanism of an electric steering gear, which comprises a shell and a worm arranged in the shell, wherein a bearing is arranged at the end part of the shell corresponding to the worm, the clearance compensation mechanism comprises a plunger and a pressing block, an opening hole is arranged on the shell corresponding to the bearing at the end part, the plunger is matched with the opening hole through threads, and the pressing block is arranged between the bearing and the plunger; because both ends of the worm adopt the conventional positioning structure, the center distance adjustment compensation range of the worm wheel and the worm is smaller, and the stability and the reliability of long-term use are poor.

Disclosure of Invention

Aiming at the defects of the prior art, the utility model provides an electric steering speed reducing mechanism with an adjustable center distance between a worm wheel and a worm, so as to achieve the purpose of improving the compensation range of the center distance between the worm wheel and the worm.

In order to solve the technical problems, the utility model adopts the following technical scheme:

the electric steering speed reducing mechanism with the adjustable center distance between the worm wheel and the worm comprises a speed reducing mechanism box body, a motor shaft, and the worm wheel and the worm which are meshed with each other, wherein the worm is arranged in the speed reducing mechanism box body through a bearing, a spring pre-tightening mechanism is arranged on the speed reducing mechanism box body corresponding to an outer end bearing of the worm, one end of the motor shaft is connected with the inner end of the worm through a kidney-shaped spline structure, and a bearing corresponding to the inner end of the worm is a deflection bearing.

Further:

the outer end bearing of the worm is a deep groove ball bearing, and a self-lubricating bearing sleeve is arranged on the outer ring of the deep groove ball bearing.

The outer edge of one end of the motor shaft is provided with a waist-shaped external spline, the inner end of the worm is of a hollow structure, and an internal spline matched with the waist-shaped external spline is arranged in the hollow structure of the inner end of the worm.

The spring pre-tightening mechanism is arranged corresponding to the self-lubricating bearing sleeve.

The worm is a large end corresponding to the deflection bearing end, and a small end corresponding to the self-lubricating bearing sleeve end.

The bottom of the hollow structure of the worm is provided with an inner spring acting on the end part of the motor shaft.

The middle position of the deflection bearing corresponding to the waist-shaped external spline is arranged.

The spring pre-tightening mechanism comprises a spring locking screw and a pre-tightening spring, a mounting hole is formed in the reduction mechanism box body corresponding to the self-lubricating bearing sleeve, the spring locking screw is arranged in the mounting hole, and the pre-tightening spring is located between the inner end of the spring locking screw and the self-lubricating bearing sleeve.

The spring pre-tightening mechanism is arranged obliquely downwards, and the included angle between the spring pre-tightening mechanism and the horizontal of the speed reducing mechanism box body is 30-40 degrees.

The pretightening force range of the pretightening spring is 20-30N.

Compared with the prior art, the utility model has the following advantages:

the electric steering speed reducing mechanism with the adjustable center distance between the worm wheel and the worm is reasonable in structural design, the shaft end of the motor is designed into a kidney-shaped spline, the large end bearing of the worm adopts a deflection bearing, the small end of the worm adopts a self-lubricating bushing to wrap the deep groove ball bearing of the small end of the worm, a pre-tightening spring with a specific angle is arranged outside the self-lubricating bushing, the center distance compensation range of the worm wheel and the worm is large, and the electric steering speed reducing mechanism is stable and reliable in long-term use.

Drawings

The contents and the marks in the drawings expressed in the drawings of the present specification are briefly described as follows:

fig. 1 is a schematic diagram of a speed reducing mechanism according to the present utility model.

Fig. 2 is an enlarged schematic view of the coupling of the present utility model.

FIG. 3 is a schematic view of a worm tail spring pretensioning mechanism according to the present utility model.

In the figure:

1. the self-lubricating gear box comprises a motor shaft, a deflection bearing, a worm, a pre-tightening spring, a spring locking screw, a self-lubricating bearing sleeve, a bearing, a worm wheel, a reduction mechanism box body and a kidney-shaped spline structure.

Detailed Description

The following description of the embodiments of the present utility model refers to the accompanying drawings, which illustrate in further detail.

As shown in fig. 1 to 3, the electric steering speed reducing mechanism with adjustable center distance between the worm wheel and the worm comprises a speed reducing mechanism box 9, a motor shaft 1, and a worm wheel 8 and a worm 3 which are meshed with each other; the worm is arranged in the reduction mechanism box body through a bearing, a spring pre-tightening mechanism is arranged on the reduction mechanism box body corresponding to the bearing at the outer end of the worm, one end of the motor shaft is connected with the inner end of the worm through a kidney-shaped spline structure 10, and the bearing arranged corresponding to the inner end of the worm is a deflection bearing 2.

In the utility model, one end of a motor shaft is connected with the inner end of a worm through a kidney-shaped spline structure, the end of the worm corresponding to the motor shaft is a large end, and the outer end of the worm is a small end; the big end bearing of the worm adopts a deflection bearing, the small end of the worm adopts a self-lubricating bushing to wrap the deep groove ball bearing of the small end of the worm, a pre-tightening spring with a specific angle is arranged outside the self-lubricating bushing, the compensation range of the center distance between the worm wheel and the worm is large, and the worm is stable and reliable in long-term use.

A waist-shaped external spline is arranged on the outer edge of one end of the motor shaft 1, the inner end of the worm is of a hollow structure, and an internal spline matched with the waist-shaped external spline is arranged in the hollow structure of the inner end of the worm 3; when the electric steering device is assembled, the end part of the motor shaft is inserted into the inner hole at the inner end of the worm, and the inner part of the worm and the waist-shaped spline at the outer part of the motor shaft are matched to form a spline transmission type coupler.

Furthermore, the bottom of the hollow structure of the worm is provided with an inner spring acting on the end part of the motor shaft, so that the connection is stable and reliable, and abnormal sound is not easy to generate. The swing bearing is arranged at the middle position corresponding to the waist-shaped external spline, namely the middle position corresponding to the arc-shaped structure, and is stable and reliable.

The outer end bearing of the worm is a deep groove ball bearing 7, the outer ring of the deep groove ball bearing is provided with a self-lubricating bearing sleeve 6, the deep groove ball bearing and the self-lubricating bearing sleeve are integrally arranged corresponding to the small end of the outer diameter of the worm, the occupied space is small, and the arrangement and the installation in the box body are convenient; the spring pre-tightening mechanism is arranged corresponding to the self-lubricating bearing sleeve. The worm is fixed in the reduction mechanism box body through a large-end deflection bearing and a small-end small-deep groove ball bearing, the self-lubricating bearing sleeve is sleeved outside the small-end small-deep groove ball bearing of the worm, the spring pre-tightening mechanism is obliquely arranged downwards, and the included angle range between the spring pre-tightening mechanism and the reduction mechanism box body is 30-40 degrees; preferably, a counter-sunk table type combined through hole is processed on the speed reducing mechanism box body at a specific angle of a=36°, and a pre-tightening spring and a spring locking screw are arranged in the counter-sunk table type combined through hole, so that the counter-sunk table type combined through hole is convenient to install and adjust; and the specific angle automatic compensation is relatively stable.

The spring pre-tightening mechanism comprises a spring locking screw 5 and a pre-tightening spring 4, a mounting hole is formed in the reduction mechanism box body corresponding to the self-lubricating bearing sleeve, the spring locking screw is arranged in the mounting hole, and the pre-tightening spring is positioned between the inner end of the spring locking screw and the self-lubricating bearing sleeve; the pretightening force of the pretightening spring ranges from 20 to 30N.

When the product is designed, the axis of the worm deviates from the meshing axis of the theoretical way by a certain angle and is far away from the worm wheel, that is, the actual center distance between the worm wheel and the worm is larger than the theoretical meshing center distance. Along with the use of a user, after the worm wheel and the worm are worn, an axial pretightening force of 20-30N is provided by the pretightening spring, the axis of the worm slowly approaches to the theoretical meshing axis until the actual center distance is smaller than the theoretical meshing center distance; the deflection bearing, the kidney-shaped spline of the motor shaft and the pre-tightening spring on the worm wheel shaft are designed, so that the axis of the worm wheel can deviate along with the pre-tightening spring force after the worm wheel is worn, the compensation range of the center distance between the worm wheel and the worm is large, and the worm wheel is stable and reliable in long-term use.

The swing amount is preset in design by combining the axis of the worm, and the meshing clearance can be effectively compensated (0-0.08 mm) after the worm wheel is worn, so that the service life of a product is prolonged, and the reliability of the product is higher; the utility model has simple structure, easy implementation, controllable performance reduction after durability, obvious idle stroke and reversing response improving effect and obviously improved reliability.

The foregoing description is only illustrative of the preferred embodiments of the present utility model, and the above-described technical features may be arbitrarily combined to form a plurality of embodiments of the present utility model.

While the utility model has been described above with reference to the accompanying drawings, it will be apparent that the utility model is not limited to the above embodiments, but is capable of being modified or applied to other applications without any modification, as long as the inventive concept and technical scheme are adopted.

Claims

1. The utility model provides an adjustable electronic steering reduction gears of worm wheel and worm centre-to-centre spacing, includes reduction gears box, motor shaft, and worm wheel and worm of intermeshing, and the worm passes through the bearing to be established in the reduction gears box, corresponds worm outer end bearing on the reduction gears box and is equipped with spring pretension mechanism, its characterized in that: one end of the motor shaft is connected with the inner end of the worm through a kidney-shaped spline structure, and a bearing arranged at the inner end of the corresponding worm is a deflection bearing.

2. The electric power steering reduction mechanism with adjustable center distance between worm wheel and worm according to claim 1, wherein: the outer end bearing of the worm is a deep groove ball bearing, and a self-lubricating bearing sleeve is arranged on the outer ring of the deep groove ball bearing.

3. The electric power steering reduction mechanism with adjustable center distance between worm wheel and worm according to claim 1, wherein: the outer edge of one end of the motor shaft is provided with a waist-shaped external spline, the inner end of the worm is of a hollow structure, and an internal spline matched with the waist-shaped external spline is arranged in the hollow structure of the inner end of the worm.

4. The electric power steering reduction mechanism with adjustable center distance between worm wheel and worm as claimed in claim 2, wherein: the spring pre-tightening mechanism is arranged corresponding to the self-lubricating bearing sleeve.

5. The electric power steering reduction mechanism with adjustable center distance between worm wheel and worm as claimed in claim 2, wherein: the worm is a large end corresponding to the deflection bearing end, and a small end corresponding to the self-lubricating bearing sleeve end.

6. The electric power steering reduction mechanism with adjustable center distance between worm wheel and worm, as claimed in claim 3, characterized in that: the bottom of the hollow structure of the worm is provided with an inner spring acting on the end part of the motor shaft.

7. The electric power steering reduction mechanism with adjustable center distance between worm wheel and worm, as claimed in claim 3, characterized in that: the middle position of the deflection bearing corresponding to the waist-shaped external spline is arranged.

8. The electric power steering reduction mechanism with adjustable center distance between worm wheel and worm according to claim 4, wherein: the spring pre-tightening mechanism comprises a spring locking screw and a pre-tightening spring, a mounting hole is formed in the reduction mechanism box body corresponding to the self-lubricating bearing sleeve, the spring locking screw is arranged in the mounting hole, and the pre-tightening spring is located between the inner end of the spring locking screw and the self-lubricating bearing sleeve.

9. The electric power steering reduction mechanism with adjustable center distance between worm wheel and worm according to claim 4, wherein: the spring pre-tightening mechanism is arranged obliquely downwards, and the included angle between the spring pre-tightening mechanism and the horizontal of the speed reducing mechanism box body is 30-40 degrees.

10. The electric power steering reduction mechanism with adjustable center distance between worm wheel and worm according to claim 8, wherein: the pretightening force range of the pretightening spring is 20-30N.