CN214493065U - Electric power steering device with steering column collapsing and output end extending - Google Patents

Abstract

The utility model provides an electric power steering device with a steering column collapsing and an output end extending, an inner spline at the rear end of a steering rod of the electric power steering device is in clearance fit with an outer spline of an input shaft; a cutting ring is arranged in the middle of the external spline of the input shaft, and a plurality of injection molding long grooves milled with splines are uniformly arranged on the circumference of the middle section of the input shaft communicated with the ring; and injection molding liquid is filled in a closed space surrounded by the circular ring, the injection molding elongated slot and the direction rod internal spline. The output end of the electric power steering device is additionally provided with a lower rotating shaft and a lower tubular column which is provided with a bearing, the inner spline of the lower rotating shaft is assembled with the outer spline of the output shaft in an interference fit manner after being heated, or the inner spline of the lower rotating shaft is connected with the outer spline of the output shaft in an injection molding manner. The utility model discloses the electronic power assisted steering device that steering column bursts to contract and the output extension is applicable to and has the tubular column to strike the protection of bursting to contract and the hard position of a steering system overall arrangement and has the condition of special requirement.

Description

Electric power steering device with steering column collapsing and output end extending

Technical Field

The utility model relates to an electric power steering device technique especially relates to an electric power steering device that steering column bursts to contract and output extension.

Background

The electric power steering device is widely applied to passenger vehicles and commercial vehicles, and the electric power steering device assembled on the electric vehicle at present can not meet the increasing requirements of consumers, for example, the consumers have high requirements on driving control feeling and driving comfort, a steering rod of the electric power steering device can not axially and radially move, and the like, and the steering column is required to have a collapsing function for meeting the requirement of a collision safety steering column. Meanwhile, the hard point layout of the steering system of the whole vehicle requires that the steering wheel is far away from the steering engine, the output end of the electric power steering device is required to be extended to be connected with a steering transmission shaft, and the steering transmission shaft is connected with the steering engine to transmit the rotating angle and the torque from the steering wheel and the power-assisted motor, so that the requirement of the steering system is met.

Therefore, an electric power steering apparatus having a steering column collapsing function and an output end extending function is needed to meet the above-mentioned needs.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a steering column collapse and the electronic power assisted steering device of output extension to present consumer to drive the requirement that controls sense and driving the travelling comfort and improve day by day and satisfy whole car special layout, and this electronic power assisted steering device's steering column structure collapses the function when having the collision, has still eliminated the axial and the radial clearance of steering yoke simultaneously. The utility model discloses electric power steering device is provided with output extension structure, satisfies this whole car turn to hard spot overall arrangement.

In order to achieve the above object, the utility model adopts the following technical scheme: an electric power steering device with a steering column collapsing and an output end extending is characterized in that the shaft diameter of the front end of a steering rod of the electric power steering device is matched with the inner diameter of a bearing of a column assembly, a first axial check ring is used for preliminarily limiting the axial direction of the steering rod, and an internal spline of the rear end of the steering rod is in clearance fit with an external spline of an input shaft; a cutting ring is arranged in the middle of the external spline of the input shaft, a plurality of injection molding long grooves with splines milled are uniformly arranged on the circumference of the middle section of the input shaft communicated with the ring, and the injection molding long grooves can be machined by adopting an injection molding long groove milling cutter; and injection molding liquid is filled in a closed space surrounded by the circular ring, the injection molding elongated slot and the direction rod internal spline. Unless otherwise stated, the rear end of the direction lever refers to the end of the direction lever close to the input shaft, and the front end of the direction lever refers to the end of the direction lever far from the output shaft.

Furthermore, 3-6 injection molding long grooves with splines milled off are uniformly arranged on the circumference of the middle section of the input shaft communicated with the circular ring, and preferably 4 injection molding long grooves with splines milled off are uniformly arranged on the circumference of the middle section of the input shaft communicated with the circular ring.

Further, the injection molding long groove is parallel to the axis of the input shaft. And the appropriate width of the circular ring and the length of the long groove are selected according to the collapse test result of the tubular column, so that the control of the collapse force is ensured within a standard requirement range, and the personal safety of the whole vehicle during impact is ensured.

Furthermore, two injection molding holes are arranged on the direction rod in a matched mode corresponding to the position of the circular ring, the injection molding holes are also arranged in a matched mode corresponding to the position of the circular ring on the pipe column assembly, injection molding is carried out after the pipe column is assembled on the upper shell, the injection molding holes are located to avoid the overlapped part of the upper pipe column and the lower pipe column of the collapse pipe column, proper injection molding pressure and proper sol viscosity are selected during injection molding, it is guaranteed that the circular ring and the four long grooves are filled with injection molding liquid, and the injection molding body plays a role in positioning and eliminating gaps after solidification.

Furthermore, the electric power steering device with the steering column collapsed and the output end extended further comprises an output end extension structure, wherein the output end extension structure comprises a lower rotating shaft and a lower column arranged outside the lower rotating shaft; the inner spline of the lower rotating shaft is connected with the outer spline at the rear end of the output shaft, and the inner spline and the outer spline at the position are selected from spline parameters capable of transmitting larger torque; the lower pipe column is lined with a bearing to support the shaft diameter of the lower rotating shaft, and the axial direction of the lower rotating shaft is initially limited by using a retaining ring for a second shaft, so that the overhanging arm of the lower rotating shaft is shortened, and the overall rigidity of the steering transmission system is improved. Unless otherwise specified, the rear end of the output shaft described herein refers to the end of the output shaft near the lower string.

Further, the method for connecting the internal spline of the lower rotating shaft with the external spline at the rear end of the output shaft comprises the following steps: heating the lower rotating shaft to realize interference fit, and assembling the lower rotating shaft while the lower rotating shaft is hot to realize interference fit;

or, the connection is performed in an injection molding mode, and the injection molding mode connection structure is as follows: the inner spline at the front end of the lower rotating shaft is in clearance fit with the outer spline of the output shaft; a cutting ring is arranged in the middle of the outer spline of the output shaft, and injection molding liquid is filled in a closed space surrounded by the ring and the inner spline of the lower rotating shaft. Unless otherwise specified, the lower spindle front end described herein refers to an end of the lower spindle close to the output shaft.

The utility model discloses the electronic power assisted steering device that steering column bursts to contract and the extension of output can be applied to and have corresponding overall arrangement and function to require on the electronic power assisted steering system of car, its structure science, reasonable, compactness, compares with prior art and has following advantage:

1) the utility model discloses when electric power assisted steering device can satisfy steering column function of collapsing, still eliminated the axial and the radial clearance of steering yoke, the utility model discloses introduced the ring between the internal spline of steering yoke and the external spline of input shaft and moulded plastics the round pin of moulding plastics and the injection molding body that the equipartition constitutes in many injection molding strips of circumference, this structure is used with the assembly process cooperation of moulding plastics, is applicable to the multiple input that requires the steering system of function and clearance control of collapsing.

2) The utility model discloses electric power steering device is provided with output extension structure, output extension structure includes pivot and lower tubular column down, no matter be the mode that adopts heating interference fit or the mode of moulding plastics, all is applicable to the condition that the steering system overall arrangement hard spot position has special requirement, makes the output shaft reduce the influence to the shafting under the fluctuation of turning to the load.

3) The pipe column crumpling and output end extending two-part structure is easy to realize by applying a proper special tool and can be used respectively under corresponding conditions.

Drawings

FIG. 1 is a perspective view of the electric power steering apparatus of the present invention, wherein the steering column is collapsed and the output end is extended;

FIG. 2 is an axial cross-sectional view of the electric power steering apparatus of the present invention in which the steering column collapses and the output end extends;

FIG. 3 is a schematic view of the input shaft;

FIG. 4 is a first cross-sectional view of the steering column in cooperation with the input shaft;

FIG. 5 is a sectional view of the steering column in cooperation with the input shaft;

FIG. 6 is a schematic structural diagram of an injection molding long slot milling cutter;

fig. 7 is a schematic diagram of an output end extension structure.

Wherein: 1. the device comprises a direction rod, 2, a pipe column assembly, 3, a sensor wire harness, 4, a motor assembly, 5, a controller assembly, 6, a mounting support, 7, a lower pipe column, 8, a lower rotating shaft, 9, a lower shaft assembly, 10, a first shaft retainer ring, 11, an input shaft, 12, an output shaft, 13, a second shaft retainer ring, 14, an upper shell, 15, a worm assembly, 16, a shaft assembly, 17, a lower shell, 18, a ring, 19, an injection molding elongated slot, 20 and an injection molding elongated slot milling cutter.

Detailed Description

The invention is further illustrated below with reference to the following examples:

example 1

The embodiment discloses an electric power steering device with a steering column capable of collapsing and an output end capable of extending, which is suitable for being assembled in a steering system with the electric power steering device capable of meeting the requirements of the input column on the collapsing function and the output end capable of extending, and the structure of the electric power steering device is shown in figures 1-5 and comprises general parts and special parts. General spare part indicates upper casing 14, lower casing 17, shafting assembly 16 (including the sensor), sensor pencil 3, motor assembly 4, controller assembly 5 (different motorcycle type match parameter is different), worm assembly 15, lower shaft assembly 9 etc. special spare part indicates steering yoke 1, input shaft 11 (belong to the shafting assembly), tubular column assembly 2, lower shaft 8, lower tubular column 7, installing support 6 etc. wherein general spare part includes the motor power supply of electronic helping hand steering device, worm gear speed reduction increases the turn round mechanism, moment of torsion and corner signal acquisition sensor to and the controller of signal collection and processing, though each family's structure is different with the implementation mode, the rationale is unanimous. The utility model discloses do not relate to functional unit such as controller, motor, sensor.

The shaft diameter of the front end of the steering column 1 is matched with the inner diameter of a bearing of the tubular column assembly 2, the left end of the steering column is the front end of the steering column in the drawing shown in figure 4, the right end of the steering column is the rear end of the steering column, the first shaft retainer ring 10 is used for preliminary axial limiting of the steering column 1, and an internal spline of the rear end of the steering column 1 is in clearance fit with an external spline of the input shaft. The structure of the input shaft is shown in fig. 3, in this example, spline parameters are shown in table 1, a cutting ring is arranged in the middle of an external spline of the input shaft 11, four injection molding long grooves 19 milled with splines are uniformly arranged on the circumference of the middle section of the input shaft 11, which is communicated with the ring 18, and the injection molding long grooves can be machined by using an injection molding long groove milling cutter 20 shown in fig. 6. In this embodiment, the length of the injection molding elongated slot is 30mm, the depth is 2mm, and the width of the ring is 5 mm. And injection molding liquid is filled in a closed space surrounded by the circular ring, the injection molding elongated slot and the direction rod internal spline. The position of the direction rod 1 corresponding to the circular ring is provided with two symmetrical injection molding holes, the position corresponding to the tubular column assembly 2 is also provided with the injection molding hole, injection molding is carried out after the tubular column is assembled on the upper shell, the injection molding hole position avoids the overlapped part of the upper tubular column and the lower tubular column of the collapse tubular column, proper injection molding pressure and sol viscosity are selected during injection molding, so that the injection molding liquid is ensured to be filled with the filled circular ring and the four elongated grooves, and the injection molding body plays a role in positioning and eliminating gaps after solidification.

TABLE 1

The key of the electric power steering device for the collapse of the steering column and the extension of the output end of the steering column is that a new structure and an injection molding assembly process are adopted for the steering column and the input shaft, an injection molding body consisting of a circular injection molding pin and four injection molding strips uniformly distributed on the circumference is introduced between an inner spline of the steering column and an outer spline of the input shaft, the effect of eliminating axial and radial gaps between the steering column and the input shaft is achieved after cooling, and when the column is impacted to realize the collapse function, the circular injection molding pin is broken by impact, and the injection molding body and the inner and outer splines rub to absorb part of impact energy in the contraction and sliding process.

Example 2

This embodiment discloses an electric power steering apparatus in which a steering column collapses and an output end extends, which has a structure substantially the same as that of embodiment 1, except that the electric power steering apparatus of this embodiment further includes an output end extending structure, which is shown in fig. 7.

The output end extension structure comprises a lower rotating shaft 8 and a lower tubular column 7, wherein the lower tubular column 7 is arranged outside the lower rotating shaft 8, a bearing is lined in the lower tubular column 7 to support the axial diameter of the lower rotating shaft 8, and a retaining ring 13 for a second shaft is used for preliminarily limiting the axial direction of the lower rotating shaft, so that the overhanging arm of the lower rotating shaft is shortened, and the overall rigidity of the steering transmission system is improved. The rear end of the output shaft 12 is reserved with a spline structure and is used for being connected with test equipment during performance test of the electric power steering device, and the lower rotating shaft 8 and the lower pipe column 7 are assembled after the performance test is completed. The output shaft 12 is connected with the lower rotating shaft 8 by adopting the injection molding mode of the direction lever and the input shaft in the embodiment 1. The internal spline at the front end of the lower rotating shaft 8 is in clearance fit with the external spline of the output shaft 12; a cutting ring is arranged in the middle of the outer spline of the output shaft 12, the width of the cutting ring is 5mm in the embodiment, and injection molding liquid is filled in a closed space surrounded by the cutting ring and the inner spline of the lower rotating shaft.

Because the lower rotating shaft is longer in overhang, the lower pipe column is additionally provided with a bearing to support the lower rotating shaft, the rigidity of a steering transmission system is improved, and the adverse effect on a shafting when the steering load fluctuates is reduced.

Example 3

The present embodiment discloses an electric power steering apparatus in which a steering column collapses and an output end extends, which has a structure substantially the same as that of embodiment 2, except that the output end extension structure of the present embodiment employs a heating assembly method.

The output end extension structure comprises a lower rotating shaft 8 and a lower pipe column 7, and a spline structure is reserved at the rear end of the output shaft 12 and used for being connected with test equipment during performance test of the electric power steering device and then being assembled with the lower rotating shaft 8 and the lower pipe column 7 after the performance test is completed. Because the output end has no collapsing requirement, the internal spline of the lower rotating shaft 8 and the external spline at the rear end of the output shaft 12 are in interference connection, the internal spline and the external spline at the position are spline parameters capable of transmitting large torque, and the specific spline parameters in the example are shown in table 2 and can be selected and matched if necessary. Because the structure can not use a press-fitting method, the interference connection is realized by adopting a method of heating the lower rotating shaft 8 and assembling the lower rotating shaft when the lower rotating shaft is hot. In the embodiment, the spline interference fit is realized by adopting the method of heating and assembling the lower rotating shaft, and the requirements on axial and radial clearances are eliminated.

TABLE 2

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention.

Claims (6)

1. An electric power steering device with a steering column collapsing and an output end extending is characterized in that the shaft diameter of the front end of a steering rod of the electric power steering device is matched with the inner diameter of a bearing of a column assembly, a first axial check ring is used for preliminarily limiting the axial direction of the steering rod, and an internal spline of the rear end of the steering rod is in clearance fit with an external spline of an input shaft; a cutting ring is arranged in the middle of the external spline of the input shaft, and a plurality of injection molding long grooves milled with splines are uniformly arranged on the circumference of the middle section of the input shaft communicated with the ring; and injection molding liquid is filled in a closed space surrounded by the circular ring, the injection molding elongated slot and the direction rod internal spline.

2. The electric power steering apparatus for steering column collapse and output end extension according to claim 1, wherein 3-6 spline-milled injection molding elongated slots are uniformly arranged on the circumference of the middle section of the input shaft communicating with the ring.

3. The electric power steering apparatus for steering column collapse and output end extension according to claim 1, wherein two injection holes are provided at positions corresponding to the rings on the steering column, and injection holes are provided at positions corresponding to the rings on the column assembly, the injection holes being positioned to avoid overlapping portions of upper and lower columns of the collapse column.

4. The electric power steering apparatus with a collapsed steering column and an extended output end according to claim 1, wherein the electric power steering apparatus with a collapsed steering column and an extended output end further comprises an output end extension structure including a lower rotation shaft and a lower column disposed outside the lower rotation shaft; the inner spline of the lower rotating shaft is connected with the outer spline at the rear end of the output shaft, the lower pipe column is lined with a bearing to support the shaft diameter of the lower rotating shaft, and the axial direction of the lower rotating shaft is initially limited by a retaining ring for a second shaft.

5. The electric power steering apparatus according to claim 4, wherein the inner spline of the lower rotary shaft is connected to the outer spline of the rear end of the output shaft by a method comprising: heating interference fit or injection molding connection.

6. The electric power steering apparatus with collapsing steering column and extending output end according to claim 5, wherein the injection-molded connection structure is as follows: the inner spline at the front end of the lower rotating shaft is in clearance fit with the outer spline of the output shaft; a cutting ring is arranged in the middle of the outer spline of the output shaft, and injection molding liquid is filled in a closed space surrounded by the ring and the inner spline of the lower rotating shaft.

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