JP2022007691A - Turning mechanism, steering unit, and caulking decision method for turning mechanism - Google Patents

Abstract

To provide a turning mechanism, a steering unit, and a caulking decision method for the turning mechanism capable of keeping quality at a certain level.SOLUTION: An overlap part O where an opening part 43 of a housing and a retainer 70 overlap in an axial direction has a caulking mark 90 showing that the overlap part has been caulked by being plastically deformed in the axial direction from the side of an opening 43a. In a plan view, at least one of the caulking mark 90 and an adjacent part 91 which is a region adjacent to the caulking mark 90 has a pigmented layer 80. The caulking mark 90 and adjacent part 91 assume different colors.SELECTED DRAWING: Figure 4

Description

The present invention relates to a steering mechanism, a steering device, and a method for determining caulking of a steering mechanism.

The steering device described in Patent Document 1 includes a pinion shaft that rotates by operating a steering wheel, a rack shaft that reciprocates in the axial direction to steer the steering wheel of a vehicle in response to the rotation of the pinion shaft, and a pinion shaft and a pinion shaft. It has a steering mechanism with a housing for accommodating the rack shaft.

Of the housing, the accommodating portion that accommodates the tip portion of the pinion shaft provided with the pinion teeth and the portion of the rack shaft provided with the rack teeth that mesh with the pinion teeth is the accommodation portion that accommodates the pinion shaft on the tip end side. It has an opening that includes an opening for insertion from. Inside the opening, a bearing that rotatably supports the pinion shaft with respect to the housing at a portion of the pinion shaft on the opening side of the pinion tooth and a retainer that prevents the bearing from coming off to the opening side are provided. ing.

The retainer is fixed to the opening through a screw between a male screw provided on the outer surface of the retainer and a female screw provided on the inner surface of the opening corresponding to the male screw.

Japanese Unexamined Patent Publication No. 2020-11662

In the steering mechanism, when the retainer is prevented from rotating, for example, the male screw of the retainer and the female screw of the opening are plastically deformed from the opening side in the axial direction to be crimped. In this case, at the manufacturing site of the steering mechanism, the crimping determination is performed to determine the quality of the caulking by visually confirming the presence or absence of the caulking marks remaining on the plastically deformed portion by visual inspection by an operator or by using equipment. The accuracy of such caulking determination may vary depending on the worker who works and the equipment used. This is disadvantageous in keeping the quality of the steering mechanism constant.

An object of the present invention is to provide a steering mechanism, a steering device, and a method for determining caulking of a steering mechanism, which can maintain constant quality.

The steering mechanism for achieving the above object has a pinion shaft having a pinion tooth at the tip and a rack tooth that meshes with the pinion tooth, and reciprocates in the axial direction to steer the steering wheel of the vehicle. A housing having a rack shaft, a housing having a housing portion that accommodates the tip portion of the pinion shaft and a portion of the rack shaft that meshes with the pinion teeth, and an opening into which the tip portion of the pinion shaft is inserted. A bearing provided inside an opening which is a portion of the accommodating portion including the pinion shaft and rotatably supporting the pinion shaft with respect to the accommodating portion at a portion of the pinion shaft on the opening side of the pinion tooth. A retainer that is screwed into the inside of the opening with the pinion shaft inserted to prevent the bearing from coming off from the opening to the opening side is provided, and the opening and the retainer are provided. However, the overlapping portions overlapping in the axial direction of the retainer have caulking marks that are caulked by being plastically deformed from the opening side in the axial direction of the retainer, and in a plan view seen from the axial direction of the retainer. A colored layer is provided on at least one of the caulking mark and the adjacent portion which is a portion adjacent to the caulking mark, and the caulking mark and the adjacent portion exhibit different colors.

According to the same configuration, since the caulking marks and the adjacent portions exhibit different colors, it is possible to confirm the presence or absence of the caulking marks as long as the difference between these colors can be determined. As a result, when the worker visually determines the caulking, the presence or absence of the caulking mark can be easily confirmed by determining the color. This is the same even when the caulking determination is performed by the equipment. Therefore, it is possible to suppress variations in the accuracy of caulking determination depending on the worker who works and the equipment used, and it is possible to keep the quality of the steering mechanism constant.

In the steering mechanism, the superposed portion is a portion where a male screw provided on the outer peripheral surface of the retainer and a female screw provided on the inner peripheral surface of the opening corresponding to the male screw are screwed together. Is preferable.

According to the same configuration, since the portion where the male screw and the female screw are screwed is crimped, the rotation of the retainer with respect to the opening to the side where the screw is released can be suppressed. This is effective in improving the function of the retainer that suppresses the bearing from coming off to the opening side.

In the steering mechanism, it is preferable that a mark is provided around the caulking mark as an index for determining the normal position of the caulking mark in the plan view.
According to the same configuration, by confirming the positional relationship between the caulking mark and the mark, it becomes possible to determine whether or not the position of the caulking mark is the normal position. As a result, when the worker visually determines the caulking, it is possible to easily determine whether or not the position of the caulking mark is the normal position by determining the positional relationship. This is the same even when the caulking determination is performed by the equipment. Therefore, it is possible to more preferably suppress the variation in the accuracy of the caulking determination depending on the worker who works and the equipment used.

In the steering mechanism, it is preferable that the mark is provided on at least one of the outer or inner sides of the retainer in the radial direction so as not to overlap with the normal position of the caulking mark in the plan view.

According to the same configuration, it is sufficient to determine whether or not the caulking mark has reached the mark as a confirmation of the positional relationship between the caulking mark and the mark in a plan view. Therefore, it is possible to realize a variation in the accuracy of the caulking determination depending on the worker who works and the equipment used, with a simpler configuration.

Here, one of the problems with the retainer screwed into the opening is that it is difficult to determine the position in the circumferential direction with respect to the opening due to the manufacturing tolerance of the housing and the retainer and the variation in the tightening torque of the retainer. ..

Therefore, in the steering mechanism, it is preferable that the mark extends along the circumferential direction about the axis of the retainer.
According to the same configuration, since the mark extends along the circumferential direction of the retainer, it is easy to provide a caulking mark adjacent to the mark even if the above-mentioned problem exists. In this case, even if a plurality of caulking marks are provided at intervals in the circumferential direction, it is easy to provide these caulking marks adjacent to the mark. Therefore, it is possible to realize a variation in the accuracy of the caulking determination depending on the worker who works and the equipment used, with an even easier configuration.

In the steering mechanism, the colored layer is preferably provided on the retainer.
According to the same configuration, a common retainer can be applied to various housings having different shapes to perform caulking determination. Therefore, the versatility of the retainer can be increased.

In the steering mechanism, the colored layer is provided on the adjacent portion, and the caulking mark is preferably a portion where the colored layer is peeled off by a tool.
According to the same configuration, the caulking mark and the adjacent portion will exhibit different colors through the actual caulking work. As a result, it is possible to easily form a caulking mark in which the caulking mark and the adjacent portion have different colors.

In the steering mechanism, the caulking mark is provided with the colored layer, and the colored layer preferably contains a paint whose color changes when a predetermined load is applied.
According to the same configuration, it is possible to add that a predetermined load acts as a condition for the caulking mark and the adjacent portion to exhibit different colors. In this case, when the caulking mark and the adjacent portion exhibit different colors, it means that at least a specified load is applied to the caulking mark. That is, at the time of caulking determination, it becomes possible to also determine whether or not a predetermined load has been applied to the caulking marks. This is effective in keeping the quality of the steering mechanism constant.

In the steering mechanism, the caulking mark is preferably a portion where the colored layer is transferred by a tool configured to transfer the colored layer.
According to this configuration, since the caulking marks and the adjacent portions exhibit different colors, it is not necessary to provide a colored layer in advance in the openings and the portions where the caulking marks of the retainer are to be provided. Therefore, it is possible to reduce the scale of change for adding the configuration necessary for the caulking marks and the adjacent portions to exhibit different colors.

In the steering mechanism, it is preferable that a pattern as an index for determining the presence or absence of the caulking mark is provided adjacent to the caulking mark in the plan view.
According to the same configuration, by checking the pattern, it becomes easy to check the presence or absence of caulking marks.

Specifically, the steering mechanism can be realized as a steering device configured to steer the steering wheel of the vehicle in response to the operation of the steering wheel of the vehicle.
According to this configuration, it is possible to suppress variations in the accuracy of caulking determination depending on the worker who works and the equipment used, and it is possible to keep the quality of the steering device constant.

Further, the caulking determination method of the steering mechanism for achieving the above object is a caulking determination method for determining the quality of caulking in the steering device, and the image of the overlapping portion in the plan view captured by the camera is used. Based on this, the presence or absence of the caulking mark is determined by detecting the color of the caulking mark, which is provided around the caulking mark in the plan view and serves as an index for determining the normal position of the caulking mark. The position of the caulking mark is determined by determining the positional relationship between the mark and the caulking mark based on the image.

According to this method, it is possible to suppress variations in the accuracy of caulking determination depending on the worker who works and the equipment used, and it is possible to keep the quality of the steering mechanism constant. Further, since the caulking determination can be performed more quickly than in the case where the operator visually determines the caulking, the productivity of the steering mechanism can be improved.

According to the present invention, the quality of the steering mechanism and the steering device can be kept constant.

The schematic diagram which shows the structure of the steering mechanism and the electric power steering apparatus of 1st Embodiment. The cross-sectional view which shows the accommodating part of the steering mechanism of 1st Embodiment. FIG. 3 is a plan view showing a configuration of the steering mechanism of the first embodiment when the accommodating portion is viewed from the opening side. FIG. 3 is an enlarged cross-sectional view showing a polymerization portion centered on a caulking mark in the portion A of FIG. The enlarged plan view which shows the polymerization part centering on the caulking mark in the part A of FIG. A plan view showing the state of the retainer before caulking. The cross-sectional view which shows the process of crimping a polymer part by a tool. The schematic diagram which shows the structure of the caulking judgment system. The enlarged sectional view which shows the overlapping part of the steering mechanism of 2nd Embodiment. The enlarged sectional view which shows the overlapping part of the steering mechanism of 3rd Embodiment. The enlarged plan view which shows the superposed part of the steering mechanism of 4th Embodiment. The schematic diagram which shows the structure of the electric power steering apparatus of the modification example.

<First Embodiment>
Hereinafter, the first embodiment of the steering mechanism, the steering device, and the caulking determination method of the steering mechanism will be described with reference to FIGS. 1 to 8.

The steering device of the present embodiment assists the driver's steering operation by transmitting the rotational motion of the motor to the ball screw mechanism via the belt-type deceleration mechanism and converting the rotational motion of the motor into the linear motion of the rack shaft. It is an electric power steering device (hereinafter referred to as "EPS") of the vehicle.

As shown in FIG. 1, the EPS 1 includes a steering shaft 11 that rotates based on the operation of the driver's steering wheel 10, and a part of the steering shaft 11, and steers the steering wheel 18 according to the rotation of the steering shaft 11. It is provided with a steering mechanism 2 for steering and an assist mechanism 3 for assisting the driver's steering operation.

The steering shaft 11 has a column shaft 12 connected to the steering wheel 10 of the vehicle, an intermediate shaft 13 connected to the tip of the column shaft 12, and a pinion shaft 14 connected to the tip of the intermediate shaft 13. ing.

The steering mechanism 2 includes a pinion shaft 14 that is a part of the steering shaft 11 and a rack shaft 15 that reciprocates in the axial direction in conjunction with the rotation of the steering shaft 11.

The tip portion 14a of the pinion shaft 14 is connected to the rack shaft 15 via a rack and pinion mechanism 16. The rack and pinion mechanism 16 is configured by engaging the pinion teeth 14b provided on the tip end portion 14a of the pinion shaft 14 with the rack teeth 15a provided on the rack shaft 15. Therefore, the rotational movement of the steering shaft 11 is converted into a reciprocating movement in the axial direction of the rack shaft 15 via the rack and pinion mechanism 16. The axial direction of the rack shaft 15 is the left-right direction in FIG.

Steering wheels 18 are connected to both ends of the rack shaft 15 via tie rods 17. The reciprocating motion of the rack shaft 15 is transmitted to the left and right steering wheels 18 via the tie rods 17, so that the steering angle of the steering wheels 18 is changed. Each tie rod 17 is connected to the rack shaft 15 in a state of being inclined with respect to the axial direction of the rack shaft 15.

The steering mechanism 2 includes a housing 20 that accommodates the tip portion 14a of the pinion shaft 14 and the rack shaft 15. The housing 20 is made of a metal material such as an aluminum alloy. The housing 20 has a housing main body 30 and an accommodating portion 40 provided integrally with the housing main body 30.

The rack shaft 15 is housed in the housing body 30. The housing body 30 has a cylindrical shape extending in the axial direction of the rack shaft 15. Both ends of the housing body 30 are open. The housing main body 30 has an assist mechanism accommodating portion 31 accommodating the assist mechanism 3. The assist mechanism accommodating portion 31 is a portion protruding in the vertical direction in FIG. 1, which is outside in the radial direction on one end side of the central portion in the axial direction of the housing main body 30.

The assist mechanism 3 includes a motor 50 that is a source of assist force, and a power transmission mechanism DK that mechanically connects the motor 50 and the rack shaft 15 so as to transmit the rotation of the motor 50 to the rack shaft 15. .. In the present embodiment, the steering mechanism 2 having a mechanical configuration and the assist mechanism 3 having a mechanical and electrical configuration operate so as to generate a steering force for steering the steering wheel 18. It constitutes a steering device.

The portion where the power transmission mechanism DK and the power transmission mechanism DK of the rack shaft 15 are provided is covered with the assist mechanism accommodating portion 31.
The motor 50 is assembled to the outer wall of the assist mechanism accommodating portion 31 by bolts 52 so that its rotation shaft 51 is parallel to the rack shaft 15. The rotation shaft 51 of the motor 50 extends to the inside of the assist mechanism accommodating portion 31 through a through hole 53 provided in the assist mechanism accommodating portion 31. The power transmission mechanism DK includes a ball screw mechanism 54 attached to the outer periphery of the rack shaft 15 and a belt type speed reduction mechanism 55 that decelerates and transmits the rotation of the rotation shaft 51 of the motor 50 to the ball screw mechanism 54.

The accommodating portion 40 is a portion protruding upward in FIG. 1, which is outside in the radial direction on the side opposite to the portion where the assist mechanism accommodating portion 31 is provided with the central portion in the axial direction of the housing main body 30 interposed therebetween. Is. The accommodating portion 40 accommodates a tip portion 14a of the pinion shaft 14 and a portion of the rack shaft 15 that meshes with the pinion teeth 14b. The accommodating portion 40 is provided so as to communicate with the housing main body 30 at a portion in the middle of the housing main body 30 in the length direction.

As shown in FIG. 2, the accommodating portion 40 has a first accommodating portion 41 extending in one radial direction of the housing main body 30 and a direction different from the one radial direction of the housing main body 30 from the first accommodating portion 41. It has a second accommodating portion 42 that extends. One radial direction of the housing body 30 coincides with the axial direction of the pinion shaft 14. The direction different from one radial direction of the housing body 30 coincides with the direction from the pinion teeth 14b to the rack teeth 15a at the portion where the rack teeth 15a of the rack shaft 15 are engaged with the pinion teeth 14b of the pinion shaft 14. do. The inside of the first accommodating portion 41 and the inside of the second accommodating portion 42 communicate with each other.

At one end of the end of the first accommodating portion 41 extending from the housing main body 30, an opening 43 including an opening 43a opened on the one end side is provided. The pinion shaft 14 is inserted into the first accommodating portion 41 from the side where the tip portion 14a is provided through the opening 43a of the opening 43.

The second accommodating portion 42 accommodates a part of the portion of the rack shaft 15 provided with the rack teeth 15a and a rack guide 60 that reciprocally supports the rack shaft 15 while pressing it toward the pinion shaft 14. ing. The rack guide 60 is urged toward the rack shaft 15 by an elastic member (not shown). The rack guide 60 has a support surface 60a having an arcuate cross section that supports the rack shaft 15. The support surface 60a is provided with a seat member (not shown) for enhancing the slidability of the rack shaft 15 and the rack guide 60.

The first accommodating portion 41 has a substantially cylindrical shape, and has a first portion 44, a second portion 45, and a third portion 46, which are sequentially connected from the opening 43a side. The first portion 44 is a portion within a predetermined range from the opening 43a in the axial direction. The second portion 45 is a portion whose inner diameter is smaller than that of the first portion 44. The third portion 46 is a portion whose inner diameter is smaller than that of the second portion 45. Therefore, a stepped portion 47 having a plane facing the opening 43a is formed at the boundary portion between the first portion 44 and the second portion 45 inside the first accommodating portion 41. Further, a stepped portion 48 having a plane facing the opening 43a is formed at the boundary portion between the second portion 45 and the third portion 46 inside the first accommodating portion 41. In the present embodiment, the opening 43 is a portion including the first portion 44 and the second portion 45.

A female screw 40a is provided on the inner peripheral surface of the second portion 45 on the opening 43a side. The female screw 40a is provided along the axial direction of the corresponding portion of the inner peripheral surface of the second portion 45.

The bottom portion 49 of the first accommodating portion 41 facing the opening 43a is provided with a concave recess 49a having a depth in the axial direction. A first bearing 61 is provided in the recess 49a. The first bearing 61 rotatably supports the first support portion 14c, which is a portion of the tip portion 14a of the pinion shaft 14 on the tip side of the pinion tooth 14b. The first bearing 61 is, for example, a needle roller bearing.

A second bearing 62 is provided in a portion of the inside of the second portion 45 between the portion where the female screw 40a is provided and the step portion 48 where the female screw 40a is not provided. The second bearing 62 is provided in a state where one end side in the axial direction thereof is in contact with the flat surface of the step portion 48 from the opening 43a side. The second bearing 62 rotatably supports the second support portion 14d, which is a portion of the pinion shaft 14 adjacent to the opening 43a side of the tip portion 14a. The second bearing 62 is, for example, a ball bearing. The diameter of the second bearing 62 is substantially the same as the inner diameter of the second portion 45. The second bearing 62 is an example of a bearing.

As shown in FIGS. 2 and 3, a retainer 70 for suppressing the removal of the second bearing 62 toward the opening 43a is screwed into a portion of the inside of the second portion 45 where the female screw 40a is provided.
The retainer 70 is made of a metal material such as an aluminum alloy. The retainer 70 has a substantially cylindrical shape.

In the following description, the axial direction of the retainer 70 is simply referred to as an axial direction. Further, the circumferential direction centered on the axis of the retainer 70 is simply referred to as a circumferential direction. Further, the radial direction centered on the axis of the retainer 70 is simply referred to as a radial direction. Further, the plan view of the steering mechanism 2 viewed from the opening 43a side in the axial direction is simply referred to as a plan view.

A through hole 71 penetrating in the axial direction is provided in the central portion of the retainer 70 in a plan view. A pinion shaft 14 is inserted into the through hole 71. The diameter of the through hole 71 is slightly smaller than the diameter of the portion of the pinion shaft 14 located in the through hole 71.

A concave recess 72 having a depth in the axial direction is provided at a portion of the retainer 70 on the opening 43a side. The recess 72 is provided so as to extend radially with respect to the outside in the radial direction with the through hole 71 as the center. The recess 72 has a substantially hexagonal shape in a plan view. The recess 72 functions as a portion to which a tool having a hexagonal columnar engaging portion (not shown) engages when the retainer 70 is screwed into the second portion 45.

On the outer peripheral surface of the retainer 70, a male screw 70a corresponding to the female screw 40a provided in the second portion 45 which is a part of the opening 43 is provided. The male screw 70a is provided along the axial direction over the entire outer peripheral surface of the retainer 70. The retainer 70 is fixed to the second portion 45 through screwing the male screw 70a and the female screw 40a of the second portion 45. Therefore, the retainer 70 is screwed into the opening 43 with the pinion shaft 14 inserted.

As shown in FIG. 4, in a state where the retainer 70 is screwed into the second portion 45, that is, the opening 43, the outermost end 70b of the male screw 70a on the opening 43a side is on the opening 43a side in the axial direction of the female screw 40a. It is located on the opening 43a side of the outermost end 40b.

As shown in FIGS. 3 to 5, a colored layer 80 is provided on one surface 73 in the axial direction in which the recess 72, which is a portion of the retainer 70 on the opening 43a side, is provided. The colored layer 80 is colored by a method such as plating or painting.

The overlapping portion O in which the second portion 45 and the retainer 70 overlap in the axial direction has a plurality of caulking marks 90 crimped by being plastically deformed in the axial direction from the opening 43a side. In the present embodiment, the polymerization portion O is a portion where the male screw 70a of the retainer 70 and the female screw 40a of the second portion 45 are screwed together. In the present embodiment, the two caulking marks 90 are provided at positions opposite to each other with the through hole 71 interposed therebetween. The caulking marks 90 are provided at equal intervals in the circumferential direction of the retainer 70. The caulking mark 90 has a circular shape in a plan view.

As shown in FIGS. 4 and 5, in the caulking mark 90, of the parts including the outermost end 70b of the male screw 70a and the outermost end 40b of the female screw 40a, the part defined as the normal position of the caulking mark 90 is plastic. It is a part formed by being deformed. This normal position is set so as to straddle the boundary portion between the second portion 45, which is a part of the first accommodating portion 41, and the retainer 70. That is, the normal position is set so as to straddle the step portion 47, the outermost end 40b of the female screw 40a, and the outermost end 70b of the male screw 70a. In the present embodiment, the normal position is defined as a range in which the caulking mark 90 can overlap with the overlapping portion O in a plan view.

The portion of the surface 73 of the retainer 70 corresponding to the caulking mark 90 is the portion where the colored layer 80, which should have been provided if caulking was not performed, was peeled off. Therefore, in the caulking mark 90, the uncolored surface 73 of the retainer 70 before the colored layer 80 is provided is exposed. On the other hand, the colored layer 80 is exposed on the surface 73 of the retainer 70 in the adjacent portion 91 which is a peripheral portion adjacent to the caulking mark 90. Therefore, in the plan view, the caulking mark 90 and the adjacent portion 91 exhibit different colors from each other.

As shown in FIGS. 3 to 5, the surface 73 of the retainer 70 is provided with a mark 74 as an index for determining the normal position of the caulking mark 90. The mark 74 is a groove having a depth in the axial direction from the surface 73 of the retainer 70. The mark 74 is provided inside the retainer 70 in the radial direction with respect to the normal position in a plan view. The mark 74 forms a perfect circle centered on the axis of the retainer 70 in a plan view. That is, the mark 74 is provided so as not to overlap with the caulking mark 90 in this case on the premise that the caulking mark 90 is provided at the above-mentioned normal position.

Next, the procedure for forming the caulking mark 90 will be described.
As shown in FIG. 6, first, one uncolored surface 73 in the axial direction provided with the recess 72 of the retainer 70 in the state before being attached to the accommodating portion 40 is colored by a method such as plating or painting. By doing so, the colored layer 80 is provided. At this time, as shown by the alternate long and short dash line in the figure, the colored layer 80 is the entire surface of the uncolored surface 73 including the planned portion 90a, which is the portion where the caulking mark 90 is planned to be provided in the retainer 70 through the step described later. It is provided in. The colored layer 80 may be provided on the entire outer surface of the retainer 70 other than the one surface 73 in the axial direction in which the recess 72 is provided.

Then, as shown in FIG. 7, in the first step, the colored retainer 70 provided with the colored layer 80 is attached to the opening 43, that is, the accommodating portion 40 through a screw between the second portion 45 and the colored retainer 70. .. As a result, in a plan view, the polymerization portion O including the scheduled portion 90a appears in the second portion 45 and the retainer 70.

In the subsequent step, the tool T is used to plastically deform the polymerized portion O from the opening 43a side to crimp it. In this case, the tool T is positioned so that its tip faces the portion corresponding to the planned portion 90a of the polymerization portion O from the opening 43a side in the axial direction. This positioning is positioned so that the scheduled portion 90a is included in the normal position. After that, the tool T moves so that its tip approaches the planned portion 90a facing in the axial direction from the opening 43a side. When the tool T comes into contact with the scheduled portion 90a, the tool T applies a predetermined load to the scheduled portion 90a and performs caulking through movement of a specified stroke along the axial direction. As a result, as shown in FIG. 4, a caulking mark 90 is formed at the normal position.

The tool T is attached to a caulking device (not shown). The tool T is configured to apply a specified load and reciprocate with a specified stroke along the axial direction. Therefore, in the present embodiment, the size and depth of the caulking mark 90 can be kept constant within the tolerance range.

Here, by crimping the polymerization portion O using the tool T, the above-mentioned specified load is applied to the colored layer 80 provided in the planned portion 90a. As a result, the adhesion between the colored layer 80 and the scheduled portion 90a is weakened, and the colored layer 80 is peeled off from the scheduled portion 90a. Therefore, the colored layer 80 remains in the adjacent portion 91 adjacent to the caulking mark 90, while the uncolored surface 73 having a color different from that of the colored layer 80 appears in the caulking mark 90. Therefore, the caulking mark 90 is a portion where the colored layer 80 has been peeled off using the tool T. In the present embodiment, in the caulking mark 90, the colored layer 80 is peeled off from the entire planned portion 90a, which is a portion to which the specified load is applied.

Next, a caulking determination method for determining the quality of caulking in the steering mechanism 2 will be described.
In the present embodiment, the caulking determination system 100 is used to perform caulking determination.
As shown in FIG. 8, the caulking determination system 100 includes a pair of cameras 101 and a computer 102 to which each camera 101 is connected.

Each camera 101 is arranged in a state in which the orientation of the first accommodating portion 41 of the steering mechanism 2 is adjusted so as to include a position corresponding to each caulking mark 90 in a plan view. Each camera 101 captures an image of the layered portion O including a portion corresponding to each caulking mark 90 in a plan view. The image information regarding the image thus captured is output to the computer 102.

Image information is input to the computer 102. The computer 102 obtains various information necessary for caulking determination by performing predetermined image processing on the image information. The computer 102 detects the color of the caulking mark 90 based on the above-mentioned various information. In this case, the computer 102 determines the presence or absence of the caulking mark 90 through the determination of whether or not the color of the caulking mark 90 is different from that of the adjacent portion 91. Whether or not the color of the caulking mark 90 is different from that of the adjacent portion 91 is determined by using a method of determining whether or not the color of the caulking mark 90 is the specified color which is the color of the uncolored surface 73. Alternatively, a method of making a judgment through comparison with the color of the adjacent portion 91 may be used. In any case, as a result of detecting the color of the caulking mark 90, the computer 102 determines whether or not there is a portion where the colored layer 80 is not provided, thereby determining the presence or absence of the caulking mark 90. ..

Further, the computer 102 also determines the positional relationship between the mark 74 and the caulking mark 90 based on the above-mentioned various information. In this case, the computer 102 determines whether or not the position of the caulking mark 90 is a normal position through the determination of whether or not the caulking mark 90 exists outside the retainer 70 in the radial direction with respect to the mark 74. Then, when the computer 102 determines that the position of the caulking mark 90 is a normal position, it determines that the caulking has been properly performed. On the other hand, when the computer 102 determines that the position of the caulking mark 90 is not a normal position and is deviated, or that the caulking mark 90 itself does not exist in the first place, it is determined that the caulking is not properly performed.

The operation of this embodiment will be described.
According to the present embodiment, since the caulking mark 90 and the adjacent portion 91 exhibit different colors, it is possible to confirm the presence or absence of the caulking mark 90 as long as the difference between these colors can be determined. Thereby, when the caulking determination is performed by the equipment realized by the caulking determination system 100, the presence or absence of the caulking mark 90 can be easily confirmed by determining the color.

The effect of this embodiment will be described.
(1) The overlapping portion O in which the opening 43 of the housing 20 and the retainer 70 overlap each other in the axial direction has a caulking mark 90 crimped by being plastically deformed in the axial direction from the opening 43a side. A colored layer 80 is provided on the adjacent portion 91, which is a portion adjacent to the caulking mark 90. The caulking mark 90 and the adjacent portion 91 have different colors.

According to such a configuration, since the above-mentioned action is obtained, it is possible to suppress the variation in the accuracy of the caulking determination depending on the equipment realized by the caulking determination system 100, and to keep the quality of the steering mechanism 2 and the EPS 1 constant. Can be done.

(2) The polymerization portion O is a portion where the male screw 70a provided on the outer peripheral surface of the retainer 70 and the female screw 40a provided on the inner peripheral surface of the opening 43 corresponding to the male screw 70a are screwed together.
According to such a configuration, since the portion where the male screw 70a and the female screw 40a are screwed together is crimped, the rotation of the retainer 70 with respect to the opening 43 toward the side where the screwing is released can be suppressed. This is effective in improving the function of the retainer 70 that suppresses the removal of the second bearing 62 to the opening 43a side.

(3) Around the caulking mark 90, a mark 74 is provided as an index for determining the normal position of the caulking mark 90 in a plan view.
According to such a configuration, by confirming the positional relationship between the caulking mark 90 and the mark 74, it becomes possible to determine whether or not the position of the caulking mark 90 is a normal position. Thereby, when the caulking determination is performed by the caulking determination system 100, it is possible to easily determine whether or not the position of the caulking mark 90 is a normal position by determining the positional relationship. Therefore, it is possible to more preferably suppress the variation in the accuracy of the caulking determination depending on the equipment realized by the caulking determination system 100.

(4) The mark 74 is provided inside the retainer 70 in the radial direction so as not to overlap the normal position of the caulking mark 90 in a plan view.
According to such a configuration, it is sufficient to determine whether or not the caulking mark 90 reaches the mark 74 in order to confirm the positional relationship between the caulking mark 90 and the mark 74 in a plan view. Therefore, it is possible to realize a variation in the accuracy of the caulking determination depending on the equipment realized by the caulking determination system 100 with a simpler configuration.

(5) The mark 74 extends along the circumferential direction.
One of the problems with the retainer 70 screwed into the opening 43 is that it is difficult to determine the position in the circumferential direction with respect to the opening 43 due to manufacturing tolerances of the housing 20 and the retainer 70, variations in the tightening torque of the retainer 70, and the like. It is one.

In this respect, according to the above configuration, since the mark 74 extends along the circumferential direction of the retainer 70, even if the above-mentioned problem exists, the caulking mark 90 can be easily provided adjacent to the mark 74. In this case, even if a plurality of caulking marks 90 are provided at intervals in the circumferential direction, it is easy to provide these caulking marks 90 adjacent to the mark 74. Therefore, it is possible to realize a variation in the accuracy of the caulking determination depending on the equipment realized by the caulking determination system 100 with an even easier configuration.

(6) The colored layer 80 is provided on the retainer 70.
According to such a configuration, a common retainer 70 can be applied to various housings 20 having different shapes to perform caulking determination. Therefore, the versatility of the retainer 70 can be increased.

(7) A colored layer 80 is provided on the adjacent portion 91, and the caulking mark 90 is a portion where the colored layer 80 is peeled off by the tool T.
According to such a configuration, the caulking mark 90 and the adjacent portion 91 exhibit different colors through the actual caulking work. Thereby, the caulking mark 90 in which the caulking mark 90 and the adjacent portion 91 exhibit different colors can be easily formed.

(8) The caulking determination method determines the presence or absence of the caulking mark 90 by detecting the color of the caulking mark 90 based on the image of the overlapping portion O in the plan view captured by the camera 101. Further, the position of the caulking mark 90 is determined by determining the positional relationship between the mark 74 and the caulking mark 90 based on the above image.

According to such a method, it is possible to suppress the variation in the accuracy of the caulking determination depending on the equipment realized by the caulking determination system 100, and it is possible to keep the quality of the steering mechanism 2 and the EPS 1 constant. Further, since the caulking determination can be performed more quickly than in the case where the operator visually determines the caulking, the productivity of the steering mechanism 2 and eventually the EPS 1 can be improved.

<Second Embodiment>
Hereinafter, the second embodiment of the steering mechanism will be described with reference to FIG. 9, focusing on the differences from the first embodiment.

In the second embodiment, the same reference numerals are given to the same configurations as those of the first embodiment, and the corresponding configurations are designated by adding "200" to the reference numerals "**" of the first embodiment. By adding "2 **", duplicate explanations will be omitted.

As shown in FIG. 9, the colored layer 280 of the present embodiment contains a paint whose color changes when a specified load is applied. As such a paint, for example, those containing microcapsules containing pigments, dyes and the like can be used. In this case, the microcapsules are destroyed by the action of the specified load on the paint. As a result, the color of the portion of the colored layer 280 on which the specified load is applied changes. As a result, colored layers 280 and 280a exhibiting different colors appear in the caulking mark 90 and the adjacent portion 91. That is, the colored layer 280a is a portion where the color of the colored layer 280 is changed by providing the caulking mark 90 in the portion of the polymerization portion O where the colored layer 280 is provided.

In the present embodiment, in addition to the above effects (1) to (6), the following effects are further exerted.
(9) The caulking mark 90 is provided with a colored layer 280a, and the colored layer 280a contains a paint whose color changes when a predetermined load is applied.

According to such a configuration, it is possible to add that a predetermined load acts as a condition for the caulking mark 90 and the adjacent portion 91 to exhibit different colors. In this case, when the caulking mark 90 and the adjacent portion 91 have different colors, it means that at least a specified load is applied to the caulking mark 90. That is, at the time of caulking determination, it becomes possible to also determine whether or not a predetermined load is applied to the caulking mark 90. This is effective in keeping the quality of the steering mechanism 2 and, by extension, EPS 1 constant.

<Third Embodiment>
Hereinafter, the third embodiment of the steering mechanism will be described with reference to FIG. 10, focusing on the differences from the first embodiment.

In the third embodiment, the same reference numerals are given to the same configurations as those of the first embodiment, and the corresponding configurations are designated by adding "300" to the reference numerals "**" of the first embodiment. By adding "3 **", duplicate explanations will be omitted.

As shown in FIG. 10, in the present embodiment, the colored layer 380 using the tool T coated with the paint 380a is provided at the time of caulking. In the present embodiment, the retainer 70 before being attached to the accommodating portion 40 is uncolored.

The caulking mark 90 is formed as a portion to which the paint 380a applied to the tool T is transferred using the tool T. As shown in the figure, the retainer 70 may have a colored layer 381 as long as it has a color different from the color of the paint 380a.

In the present embodiment, in addition to the above effects (1) to (6), the following effects are further exerted.
(10) The caulking mark 90 is a portion where the colored layer 380 is transferred by the tool T configured to transfer the colored layer 380.

According to such a configuration, since the caulking mark 90 and the adjacent portion 91 exhibit different colors, it is not necessary to provide a colored layer in advance on the scheduled portion 90a. Therefore, it is possible to suppress the scale of change for adding the configuration necessary for the caulking mark 90 and the adjacent portion 91 to exhibit different colors.

<Fourth Embodiment>
Hereinafter, the fourth embodiment of the steering mechanism will be described with reference to FIG. 11, focusing on the differences from the first embodiment.

In the fourth embodiment, the same components as those in the first embodiment are designated by the same reference numerals, so that duplicate description will be omitted.
As shown in FIG. 11, in the present embodiment, a tool having a tip shape capable of transferring the pattern 92, which is an index for determining the presence or absence of the caulking mark 90, is used at the time of caulking.

The retainer 70 of the present embodiment is formed with a pattern 92 as an index for determining the presence or absence of a caulking mark 90 through caulking. In this case, the pattern 92 is formed adjacent to the caulking mark 90 in a plan view. In the present embodiment, the pattern 92 is a ridge extending in a predetermined direction within the range in which the caulking mark 90 is formed. In addition to the ridges, the pattern 92 may be, for example, a groove or a dimple.

In the present embodiment, in addition to the above effects (1) to (6), the following effects are further exerted.
(11) A pattern 92, which is an index for determining the presence or absence of the caulking mark 90, is provided adjacent to the caulking mark 90 in a plan view.

According to such a configuration, by confirming the pattern 92, it becomes easy to confirm the presence or absence of the caulking mark 90.
<Change example>
Each of the above embodiments can be modified and implemented as follows. Each of the above embodiments and the following modification examples can be implemented in combination with each other within a technically consistent range.

In each of the modified examples shown below, the same reference numerals are given to the same configurations as those of the above-described embodiments, and "100" is added to the reference numerals "**" of the above-mentioned embodiments for the corresponding configurations. By adding the reference numeral "1 **", duplicate explanations will be omitted.

-In the second embodiment, the colored layer 280a can be provided only on the planned portion 90a in the polymerization portion O.
In the third embodiment, instead of using the tool T coated with the paint 380a, the colored layer 80 can be transferred between the retainer 70 and the tool T similar to the first embodiment at the time of caulking. A sheet can also be inserted. Even in this case, the effect according to the third embodiment can be obtained.

-In the fourth embodiment, the pattern 92 may have a shape that does not contribute to the caulking of the polymerization portion O.
-In the fourth embodiment, if the pattern 92 is formed at the time of caulking, it may be provided so as to extend beyond the range where the caulking mark 90 is formed, or it may be provided away from the caulking mark 90. It may be provided at a vertical position. Even in this case, the effect according to the fourth embodiment can be obtained.

In each of the above embodiments, in the caulking determination system 100, one camera 101 is used to take an image of the polymerization portion O including a portion corresponding to each caulking mark 90 or each caulking mark 90 in a plan view. You may do so.

The caulking determination may be performed by the caulking determination system 100 up to the step of capturing the image of the polymerization section O, and the operator may visually confirm the image of the polymerization section O captured by the camera 101. In addition, the caulking determination may be basically visually confirmed by the operator, including the determination of the presence or absence of the caulking mark 90. Even in this case, the effect (1) to the effect (8) and the effect (10) to the effect (11) of each of the above embodiments can be achieved.

-In the first embodiment, the caulking mark 90 may be a portion where at least a part of the colored layer 80 provided in the scheduled portion 90a is peeled off, and has a portion where a part of the colored layer 80 remains. May be.

In each of the above embodiments, the colored layer 80 may be provided on the flat surface of the stepped portion 47 of the opening 43 as well as the surface 73 of the retainer 70.
-In each of the above embodiments, the marks 74 may be provided discontinuously at intervals in the circumferential direction of the surface 73 of the retainer 70.

-In each of the above embodiments, the mark 74 can be appropriately changed such as protrusions and various patterns as long as it can be used as an index for determining the presence or absence of the caulking mark 90.
-In each of the above embodiments, the mark 74 may be provided outside the caulking mark 90 in the radial direction. The mark 74 in this case is provided in the stepped portion 47 of the opening 43. Further, the mark 74 may be provided on the inner side and the outer side in the radial direction of the caulking mark 90.

-In each of the above embodiments, the mark 74 may be provided so as to overlap the normal position of the caulking mark 90 in a plan view. In this case, the caulking determination can be performed by determining whether or not the caulking mark 90 is provided so as to overlap the mark 74.

-In each of the above embodiments, the configuration of the mark 74 may be omitted.
In each of the above embodiments, the outermost end 40b of the female screw 40a may be located closer to the opening 43a than the outermost end 40b of the male screw 70a.

In each of the above embodiments, the retainer 70 has a diameter-expanded portion that is larger than the portion provided with the male screw 70a, and the opening 43 has a seat that the diameter-expanded portion contacts in the axial direction. It may be. In this case, the overlapping portion O is a portion where the enlarged diameter portion and the seat overlap each other in the axial direction. Further, the caulking mark 90 is formed by crimping the enlarged diameter portion and the seat together in the axial direction. The polymerization portion O and the caulking mark 90 at this time may be provided at positions separated from the portion where the male screw 70a and the female screw 40a are screwed to the outside in the radial direction.

The accommodating portion 40 and the retainer 70 may be formed of the same type of metal material, or may be formed of different types of metal materials. Regarding the combination of the metal materials of the accommodating portion 40 and the retainer 70, for example, it is preferable that their hardnesses are substantially the same as each other. According to such a configuration, when the caulking mark 90 is formed so as to straddle the boundary portion between the second portion 45 and the retainer 70, the second portion 45 and the retainer 70 are likely to be plastically deformed together. , It becomes easy to crimp the boundary part. Further, in the polymerization portion O, the male screw 70a and the female screw 40a are likely to be plastically deformed at once, so that the polymerization portion O is easily crimped.

In each of the above embodiments, as shown in FIG. 12, the EPS 1 is a steering wheel embodied in a so-called dual pinion type EPS 1, in which the rack and pinion mechanism 116 is provided in addition to the rack and pinion mechanism 16. It may be a device. In this configuration, the rack and pinion mechanism 116 is configured by engaging the pinion teeth 114b provided on the tip 114a of the pinion shaft 114 with the rack teeth 115a provided on the rack shaft 15. In addition to the accommodating portion 40, the housing 20 has an accommodating portion 140 in which a tip portion 114a of the pinion shaft 114 and a portion of the rack shaft 15 that meshes with the pinion teeth 114b are accommodated. The pinion shaft 114 is connected to the rotary shaft 151 of the motor 150 via a reduction mechanism 155 including a worm wheel, a worm gear, and the like. Although not shown, the accommodating portion 140 is provided with a bearing that rotatably supports the pinion shaft 114 and a retainer that prevents the bearing from coming off from the opening of the accommodating portion. By applying the same configuration as each of the above embodiments to the accommodating portion 140, it is possible to achieve the same effect as that of each of the above embodiments.

Each of the above embodiments may be a steering device embodied in a so-called column type EPS1 that applies an assist force to the steering shaft 11. Further, the present invention is not limited to EPS, and may be embodied in, for example, a steer-by-wire type steering device. That is, any steering device may be used as long as it is a steering device including a steering mechanism 2 that steers the steering wheel 18 in response to the operation of the steering wheel 10.

O ... Polymerization part T ... Tool 1 ... EPS (steering device)
2 ... Steering mechanism 10 ... Steering wheel 14 ... Pinion shaft 14a ... Tip 14b ... Pinion teeth 15 ... Rack shaft 15a ... Rack teeth 18 ... Steering wheel 20 ... Housing 40 ... Housing 40a ... Female screw 43 ... Opening 43a ... Opening 61 ... 1st bearing 62 ... 2nd bearing (bearing)
70 ... Retainer 70a ... Male screw 74 ... Mark 80, 280, 280a, 380, 381 ... Colored layer 90 ... Caulking marks 91 ... Adjacent part 92 ... Pattern 101 ... Camera 380a ... Paint

Claims (12)

A pinion shaft with pinion teeth at the tip,
A rack shaft having rack teeth that mesh with the pinion teeth and reciprocating in the axial direction to steer the steering wheel of the vehicle,
A housing having a housing portion that is a portion for accommodating the tip portion of the pinion shaft and the portion of the rack shaft that meshes with the pinion teeth.
The pinion shaft is provided inside an opening which is a portion of the accommodating portion including an opening into which the tip portion of the pinion shaft is inserted, and the pinion shaft is provided at a portion of the pinion shaft on the opening side of the pinion teeth. Bearings that rotatably support the housing and
A steering mechanism including a retainer that is screwed into the opening with the pinion shaft inserted to prevent the bearing from coming off from the opening to the opening side.
The overlapping portion where the opening and the retainer overlap in the axial direction of the retainer has a caulking mark that is caulked by being plastically deformed from the opening side in the axial direction of the retainer.
In a plan view seen from the axial direction of the retainer, a colored layer is provided on at least one of the caulking mark and the adjacent portion which is a portion adjacent to the caulking mark.
The caulking mark and the adjacent portion have different colors.
Steering mechanism. The polymerization portion is a portion where a male screw provided on the outer peripheral surface of the retainer and a female screw provided on the inner peripheral surface of the opening corresponding to the male screw are screwed together.
The steering mechanism according to claim 1. Around the caulking mark, a mark is provided as an index for determining the normal position of the caulking mark in the plan view.
The steering mechanism according to claim 1 or 2. The mark is provided on at least one of the radial outer side or inner side of the retainer so as not to overlap the normal position of the caulking mark in the plan view.
The steering mechanism according to claim 3. The mark extends along the circumferential direction about the axis of the retainer.
The steering mechanism according to claim 3 or 4. The colored layer is provided on the retainer.
The steering mechanism according to any one of claims 1 to 5. The colored layer is provided in the adjacent portion.
The caulking mark is a portion where the colored layer is peeled off by a tool.
The steering mechanism according to any one of claims 1 to 6. The colored layer is provided on the caulked marks.
The colored layer contains a paint whose color changes when a specified load is applied.
The steering mechanism according to any one of claims 1 to 6. The caulking mark is a portion where the colored layer is transferred by a tool configured to transfer the colored layer.
The steering mechanism according to any one of claims 1 to 6. A pattern that serves as an index for determining the presence or absence of the caulking mark is provided adjacent to the caulking mark in the plan view.
The steering mechanism according to any one of claims 1 to 9. A steering device comprising the steering mechanism according to any one of claims 1 to 10, wherein the steering wheel of the vehicle is steered in response to an operation of the steering wheel of the vehicle. The caulking determination method for determining the quality of caulking in the steering mechanism according to any one of claims 3 to 10.
The presence or absence of the caulking mark is determined by detecting the color of the caulking mark based on the image of the polymerized portion in the plan view imaged by the camera.
The caulking mark is provided around the caulking mark in the plan view, and the positional relationship between the caulking mark and the mark as an index for determining the normal position of the caulking mark is determined based on the image. Judging the position of the mark,
How to determine the caulking of the steering mechanism.

Images