KR102623890B1 - Electric Power Steering Apparatus - Google Patents

Abstract

The electric power auxiliary steering device according to the present embodiments includes a housing having a first accommodating part that is open on one side to accommodate the worm wheel, a second accommodating part that communicates with the first accommodating part and accommodates the worm shaft, and the first accommodating part. The housing and housing cover, which accommodates the worm wheel engaged with the worm shaft, including a housing cover coupled to one side and a coupling member that provides axial force to the housing and housing cover in the radial direction, are supported in the axial and radial directions, causing damage to the worm wheel. It can prevent the housing and housing cover from being separated or misaligned due to the load, and can support both axial and radial loads even if the bolts that connect the housing and housing cover are provided in small numbers or with small diameters, thus reducing the cost. This can save money and simplify the assembly process.

Description

Electric Power Steering Apparatus}

These embodiments relate to an electric power auxiliary steering device, and more specifically, the housing and housing cover that accommodate the worm wheel engaging with the worm shaft are supported in the axial and radial directions, so that the housing and housing cover are supported by the load generated on the worm wheel. It can prevent separation or misalignment, and can support both axial and radial loads even if the bolts that connect the housing and housing cover are provided in small numbers or with small diameters, which reduces costs and simplifies the assembly process. It is about auxiliary steering device.

The steering shaft of a car is equipped with a worm wheel, worm shaft, etc. to assist the driver in manipulating the steering wheel. The worm wheel is coupled to the steering wheel, and the worm shaft engages with the worm wheel and is rotated by the motor, so that the auxiliary power of the motor is transmitted to the worm shaft and the reducer of the worm wheel. It is amplified by the structure and transmitted to the steering shaft to protect the driver's steering wheel operation.

This worm wheel and worm shaft are accommodated inside a housing, where one side of the housing is open to accommodate the worm wheel, and the housing cover shields one side of the housing and is coupled to the housing.

In addition, a worm gear is formed on the outer peripheral surface of the worm shaft, and gear teeth that mesh with the worm gear are formed on the outer peripheral surface of the worm wheel. When the auxiliary power of the motor is transmitted to the worm wheel due to the shape of the worm gear, axial and radial loads are generated on the worm wheel. I do it.

However, in the conventional electric power auxiliary steering device, the bolts for connecting the housing and the housing cover are coupled only in the axial direction, so the axial load of the worm wheel is sufficiently supported by the coupling force of the bolts, but the support force for the radial load of the worm wheel is not sufficient. There was a problem that the housing and housing cover could be separated or misaligned in the radial direction.

These embodiments were developed from the above-described background, and the housing and housing cover that accommodate the worm wheel engaging with the worm shaft are supported in the axial and radial directions to prevent the housing and housing cover from being separated or misaligned due to the load generated on the worm wheel. The purpose is to reduce costs and simplify the assembly process by supporting both axial and radial loads even if the bolts that connect the housing and housing cover are provided in small numbers or with small diameters.

The purpose of the present embodiments is not limited here, and other purposes not mentioned will be clearly understood by those skilled in the art from the description below.

According to the present embodiments, a housing provided with a first accommodating part that is open on one side and accommodates a worm wheel, a second accommodating part in communication with the first accommodating part and accommodating a worm shaft, and a housing coupled to one side of the first accommodating part. An electric power assist steering device may be provided including a cover, a housing, and a coupling member that provides axial force to the housing cover in a radial direction.

According to the present embodiments, the housing and housing cover accommodating the worm wheel engaging with the worm shaft are supported in the axial and radial directions, thereby preventing the housing and housing cover from being separated or misaligned due to the load generated on the worm wheel, and the housing Even if the bolts that connect the housing cover and the housing cover are provided in small numbers or with small diameters, they can support both axial and radial loads, reducing costs and simplifying the assembly process.

1 is an exploded perspective view of a portion of an electric power auxiliary steering device according to the present embodiments.
Figure 2 is a perspective view of the combined state of the electric power auxiliary steering device according to the present embodiments.
Figure 3 is a cross-sectional view of the electric power auxiliary steering device according to the present embodiments.
Figure 4 is a perspective view of a part of the electric power auxiliary steering device according to the present embodiments.
5 to 6 are cross-sectional views of electric power auxiliary steering devices according to the present embodiments.
7 to 8 are cross-sectional views of electric power auxiliary steering devices according to the present embodiments.

Hereinafter, some embodiments of the present embodiments will be described in detail through exemplary drawings. When adding reference numerals to components in each drawing, it should be noted that identical components are given the same reference numerals as much as possible even if they are shown in different drawings. Additionally, in describing the present embodiments, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present embodiments, the detailed description will be omitted.

Additionally, in describing the components of the present embodiments, terms such as first, second, A, B, (a), and (b) may be used. These terms are only used to distinguish the component from other components, and the nature, sequence, or order of the component is not limited by the term. When a component is described as being “connected,” “coupled,” or “connected” to another component, that component may be directly connected or connected to that other component, but there is another component between each component. It will be understood that elements may be “connected,” “combined,” or “connected.”

Figure 1 is an exploded perspective view of a part of the electric power auxiliary steering device according to the present embodiments, Figure 2 is a perspective view of the combined state of the electric power auxiliary steering device according to the present embodiments, and Figure 3 is the present embodiments. 4 is a perspective view of a part of the electric power auxiliary steering device according to the present embodiments, and FIGS. 5 and 6 are cross-sectional views of the electric power auxiliary steering device according to the present embodiments. , FIGS. 7 and 8 are cross-sectional views of the electric power auxiliary steering device according to the present embodiments.

The electric power auxiliary steering device 100 according to the present embodiments includes a first accommodating part 111 with one side open to accommodate the worm wheel 121, a worm shaft 123 and a first accommodating part 111 that communicates with the first accommodating part 111. A housing 101 provided with the second accommodating part 113, a housing cover 103 coupled to one side of the first accommodating part 111, and a radial direction to the housing 101 and the housing cover 103. It includes a coupling member 131 that provides axial force.

As the coupling member 131, a bolt may be used as shown in the drawing, but it is of course not limited thereto. However, for convenience, in the detailed description of the present embodiments, the coupling member 131 will be described as consisting of a bolt.

Hereinafter, it will be looked at with reference to FIGS. 1 and 2.

The worm wheel 121 coupled to the steering shaft 201 is engaged with the worm shaft 123 rotated by a motor (not shown), and the power of the motor is amplified by the gear ratio of the worm wheel 121 and the worm shaft 123 to perform steering. It is applied to the axis 201 and assists the driver in operating the steering wheel.

A worm gear is formed on the outer peripheral surface of the worm shaft 123, and gear teeth that engage the worm gear are provided on the outer peripheral surface of the worm wheel 121. The worm wheel 121 and the worm shaft 123 are each located in the first receiving portion 111 of the housing 101. and is accommodated in the second receiving portion 113.

That is, the first accommodating part 111 and the second accommodating part 113 are partially provided in communication with each other, and a portion of the first accommodating part 111 and the second accommodating part 113 communicates with the worm wheel 121. The worm shaft 123 is engaged.

The first accommodating part 111 is open on one side to accommodate the worm wheel 121. As shown in the drawing, the first accommodating part 111 is open in the axial direction of the worm wheel 121 and has an opening on one side of the first accommodating part 111. The housing cover 103 is coupled.

By combining the housing cover 103, one open side of the first accommodating part 111 is shielded, and the steering shaft 201 penetrates the first accommodating part 111 and the housing cover 103 and is driven by a bearing. It is combined and also equipped with a torque sensor, etc.

At this time, the housing 101 and the housing cover 103 may be coupled in the axial and radial directions, that is, in the electric power auxiliary steering device according to the present embodiments, they are coupled to the first receiving portion 111 to form the housing ( The worm wheel 121 is provided with a bolt 133 for axially coupling to the housing 101) and the housing cover 103, as well as a coupling member 131 for providing axial force to the housing 101 and the housing cover 103 in the radial direction. The axial and radial loads generated when rotating in engagement with the worm shaft 123 are supported, thereby preventing the housing 101 and the housing cover 103 from being separated or misaligned.

In other words, in the conventional electric power auxiliary steering device, the housing and housing cover are assembled by bolts that are joined in the axial direction, so even if a large load occurs in the axial direction, it is difficult to cause misalignment because it is supported by the axial force of the bolt. The generated load is supported only by the frictional force generated by the axial force of the bolt on the mutually supported surfaces, so there is a problem that misalignment is easy to occur. However, in the electric power auxiliary steering device 100 according to the present embodiments, the housing 101 And the housing cover 103 is provided with a coupling member 131 that provides axial force in the radial direction, so that the housing 101 and the housing cover 103 can be prevented from being separated or misaligned even if a large load occurs in the radial direction. will be.

In addition, in the conventional electric power auxiliary steering device, bolts coupled in the axial direction may be provided with a larger diameter or in a greater number to support the radial load, but the electric power auxiliary steering according to the present embodiments It is advantageous to provide a coupling member 131 that provides axial force in the radial direction like the device 100 when considering cost, simplification of the assembly process, etc.

In addition, since the coupling member 131 is provided so that the radial load can be supported even if the friction between the housing 101 and the housing cover 103 is reduced, the diameter of the bolt 133 coupled in the axial direction can be provided to be smaller. In general, the radial load generated on the worm wheel 121 is smaller than the axial load, so the coupling member 131 can support the radial load even if it is formed with a smaller diameter than the bolt 133, thereby reducing cost, etc. It is advantageous when considering.

Meanwhile, the coupling member 131 is provided on the opposite side of the area where the first accommodating part 111 communicates with the second accommodating part 113 to provide a radial axial force to the housing 101 and the housing cover 103. This can be done, details will be explained later.

Subsequently, the coupling member 131 may be radially coupled to the first receiving portion 111 to provide radial axial force, or may be obliquely coupled to provide axial and radial axial forces.

first. Referring to FIG. 3 , an insertion portion 301 supported on the inner peripheral surface of the first accommodating portion 111 may be protruding from the housing cover 103.

Additionally, the coupling member 131 may be coupled to the first receiving portion 111 and the insertion portion 301 while penetrating in the radial direction.

That is, coupling holes communicating with each other are formed in the radial direction in the first receiving portion 111 and the insertion portion 301, and the coupling member 131 is inserted into the coupling hole, and the first receiving portion 111 and the insertion portion ( It is coupled to 301) to provide radial axial force to the housing 101 and the housing cover 103.

Additionally, a flat portion 141 may be formed on the outer peripheral surface of the first receiving portion 111. A coupling hole is formed in the flat portion 141 so that the coupling member 131 can be supported on the flat portion 141. This flat portion 141 may be formed to be stepped in the radial direction on the outer peripheral surface of the first receiving portion 111.

By providing the flat part 141, when the coupling member 131 is coupled to the coupling hole, the head portion of the coupling member 131 is supported on the flat part 141, and therefore the coupling member 131 is the first receiving part ( 111), the area supported on the outer circumferential surface is expanded and loosening can be prevented. In addition, although not shown in the drawing, it becomes easy to add components such as washers to strengthen the fastening force of the coupling member 131.

Next, the housing cover 103 may be provided with a support portion 401 that protrudes in the radial direction and is bent to support the first receiving portion 111. The coupling member 131 is coupled to the support portion 401 to form a housing. It is possible to provide radial axial force to (101) and the housing cover (103).

Referring to FIGS. 4 and 5 , the coupling member 131 may be coupled to the support portion 401 and the first receiving portion 111 while penetrating in the radial direction.

Additionally, a flat portion 141 may be provided on the outer peripheral surface of the first receiving portion 111, and the support portion 401 may be supported on the flat portion 141.

That is, the support portion 401 is vertically bent in the housing cover 103 and the inner surface is supported on the flat portion 141.

The flat portion 141 is provided and the support portion 401 is provided on the flat portion 141, so that when the coupling member 131 is coupled as described above, the head portion of the coupling member 131 is supported on the support portion 401. The larger area can prevent loosening, and it becomes easier to add components such as washers.

A coupling hole communicating with each other is formed in the axial direction of the support part 401 and the flat part 141, and the coupling member 131 is inserted into the coupling hole and is coupled to the support part 401 and the first receiving part 111 to form a housing. A radial axial force is provided to (101) and the housing cover (103).

The drawing shows an embodiment in which the coupling member 131 is coupled only to the support portion 401 and the first receiving portion 111. However, in this case, a coupling hole is also formed in the insertion portion 301, so that the coupling member 131 is coupled to the support portion 401. ), it may also be coupled to the first receiving portion 111 and the insertion portion 301.

Referring to FIG. 6 , the first accommodating portion 111 is provided with a protrusion 601 that protrudes in the radial direction, and one side of the protrusion 601 facing the housing cover 103 may be inclined.

As shown in the drawing, the protrusion 601 is formed to protrude from the outer peripheral surface of the first accommodating part 111, and one side facing the housing cover 103, that is, the left side in the drawing, may be formed to be inclined.

At this time, the support part 603 is bent and supported on one inclined side of the protrusion 601, and the coupling member 131 penetrates the support part 603 and the protrusion 601 and is coupled to them.

That is, a coupling hole communicating with each other is formed in the support part 603 and the protrusion 601, and the coupling member 131 is inserted into the coupling hole and coupled to the support part 603 and the protrusion 601. One side of the protrusion 601 By being inclined and the support portion 603 is supported on one inclined side of the protrusion 601, the coupling member 131 can provide axial force to the housing 101 and the housing cover 103 in the axial and radial directions. .

As described above, it supports the axial and radial loads generated on the worm wheel 121 to prevent the housing 101 and the housing cover 103 from being separated or misaligned, but increases the bearing capacity for the axial load and supports the radial load. The coupling member 131 is coupled to the housing 101 and the housing cover 103 at an angle so as to support the housing 101 and the housing cover 103, thereby providing axial force in both the axial and radial directions.

The drawing shows an embodiment in which one side of the protrusion 601 is inclined to the right in the drawing as it goes from the radial inner side to the outer side. However, on the contrary, it is formed to be inclined to the left in the drawing and the support portion 603 is also bent to the left and the protrusion is formed. Even if the coupling member 131 is supported on 601 and coupled to the support portion 603 and the protrusion 601, axial force may be provided to the housing 101 and the housing cover 103 in the axial and radial directions.

Meanwhile, as described above, the coupling member 131 may be provided on the opposite side of the portion in the first accommodating part 111 that communicates with the second accommodating part 113. For convenience of description below, the coupling member 131 The description will be based on an embodiment in which the flat portion 141 formed on the outer peripheral surface of the first receiving portion 111 is bent at the housing cover 103 and is coupled to the support portion 401 supported on the flat portion 141. do.

The radial load applied to the worm wheel 121 by the worm shaft 123 is generated in the direction in which the worm wheel 121 engages with the worm shaft 123 and in the opposite direction, so the coupling member 131 supports the radial load. In order to do this, it is effective to support the housing 101 and the housing cover 103 on the opposite side of the worm shaft 123, that is, on the opposite side of the area where the first accommodating part 111 communicates with the second accommodating part 113.

Therefore, as shown in FIG. 7, the first accommodating part 111 communicates with the second accommodating part 113 from the upper side in the drawing, and the coupling member 131 is coupled to the first accommodating part 111 from the lower side in the drawing. It can be.

Figure 7 shows an embodiment in which one coupling member 131 is provided. At this time, the coupling member 131 passes through the central axis of the worm wheel 121 and forms a plane perpendicular to the worm axis 123, that is, along the line A-A'. It is provided at an intersecting position and can support radial loads.

In addition, as shown in FIG. 8, two or more coupling members 131 may be provided, and similarly, each coupling member 131 is located on the opposite side of the portion in communication with the second accommodating part 113 of the first accommodating part 111. It supports the housing 101 and the housing cover 103.

Since two or more coupling members 131 are provided, two or more flat portions 141 and support portions 401 will also be provided correspondingly. Figure 8 shows an embodiment in which two coupling members 131 are provided, but more may be provided. However, as mentioned above, the radial load is smaller than the axial load, so it increases the cost and assembly process. Considering simplification, etc., it is preferable that one or two coupling members 131 are provided.

At this time, the coupling member 131 passes through the central axis of the worm wheel 121 and may be arranged symmetrically with respect to a plane perpendicular to the worm axis 123, that is, line B-B'.

Since the coupling members 131 are provided symmetrically, the radial load generated on the worm wheel 121 can be stably supported.

In order for the coupling member 131 to smoothly support the radial load, the angle formed by the coupling member 131 with the line B-B' must be formed at an acute angle, and is preferably formed within 30 degrees.

According to the electric power auxiliary steering device having such a shape, the housing accommodating the worm shaft and the worm wheel, and the housing cover are coupled not only by a bolt coupled in the axial direction but also by a coupling member that provides axial force in the radial direction, so that the rotation of the worm shaft By supporting both axial and radial loads occurring on the worm wheel, separation or misalignment of the housing and housing cover can be prevented.

In addition, since the radial load is supported by the coupling member, the diameter of the bolt supporting the axial load can be smaller or the number of bolts can be reduced, and the radial load having a size smaller than the axial load can be supported. The coupling member for this purpose can be provided to have a smaller diameter than the bolt, thereby reducing costs and simplifying the assembly process.

In the above, just because all the components constituting the embodiments of the present embodiments have been described as being combined or operated in combination, the present embodiments are not necessarily limited to these embodiments. That is, within the scope of the purpose of the present embodiments, all of the components may be operated by selectively combining one or more of them.

In addition, terms such as “include,” “comprise,” or “have” as used above mean that the corresponding component may be included, unless specifically stated to the contrary, and thus do not exclude other components. Rather, it should be interpreted as being able to include other components. All terms, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which the present embodiments belong, unless otherwise defined. Commonly used terms, such as terms defined in a dictionary, should be interpreted as consistent with the contextual meaning of the related technology and, unless clearly defined in the present embodiments, should not be interpreted in an idealized or overly formal sense.

The above description is merely an illustrative description of the technical idea of the present embodiments, and various modifications and variations can be made by those skilled in the art in the technical field to which the present embodiments belong without departing from the essential characteristics of the present embodiments. will be. Accordingly, the embodiments disclosed in the present embodiments are not intended to limit the technical idea of the present embodiments but are for explanation, and the scope of the technical idea of the present embodiments is not limited by these embodiments. The scope of protection of the present embodiments should be interpreted in accordance with the claims below, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of rights of the present embodiments.

100: Electric power assist steering device 101: Housing
103: Housing cover 111: First receiving portion
113: second receiving portion 121: worm wheel
123: Worm shaft 131: Coupling member
133: Bolt 141: Flat part
201: steering shaft 301: insertion part
401,603: support 601: protrusion

Claims (12)

A housing having a first accommodating part open on one side to accommodate a worm wheel, and a second accommodating part in communication with the first accommodating part and accommodating a worm shaft;
a housing cover coupled to one side of the first accommodating part;
A coupling member that provides axial force to the housing and housing cover in a radial direction;
Includes,
The housing cover is provided with a support portion that protrudes in the radial direction and is bent to support the first accommodating portion,
The first accommodating portion is provided with a protrusion that protrudes in a radial direction, and one side of the protrusion facing the housing cover is inclined,
The support portion is supported on one side of the protrusion, and the coupling member penetrates and couples the support portion and the protrusion. According to claim 1,
An electric power assist steering device, characterized in that an insertion portion supported on an inner peripheral surface of the first accommodating portion is protruding from the housing cover. According to claim 2,
An electric power assistance steering device, characterized in that the coupling member penetrates and is coupled to the first receiving portion and the insertion portion. delete delete According to claim 1,
An electric power assistance steering device, characterized in that the coupling member penetrates and is coupled to the support part and the first receiving part. delete delete delete According to claim 1,
An electric power assistance steering device, characterized in that the coupling member is provided on the opposite side of the first accommodating part in communication with the second accommodating part. According to claim 10,
An electric power auxiliary steering device, characterized in that two or more coupling members are provided. According to claim 11,
The coupling member passes through the central axis of the worm wheel and is arranged symmetrically with respect to a plane perpendicular to the worm axis.

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