JP2000006827A - Assembly method of control valve for power steering device and operating angle variation reduction method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an assembly method of a control valve for a power steering device capable of improving a valve characteristic, etc. SOLUTION: A control valve 30 on which a seal ring 58 is fitted is inserted into an outer peripheral part after a cylindrical insertion guide jig 94 is installed on a step part 20 for a bearing pedestal of a valve storage part 12. Thereafter, the insertion guide jig 94 is removed, and a ball bearing, etc., are assembled. Consequently, the seal ring 58 is not damaged by being caught on an edge of the step part 20 for the bearing pedestal, and it is possible to smoothly assemble the control valve 30. Accordingly, it is possible to improve a valve characteristic of the control valve 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for assembling a control valve for a power steering apparatus and a method for reducing a variation in an operating angle.

[0002]

2. Description of the Related Art A control valve (rotary valve) of a conventional rack-and-pinion type power steering apparatus will be briefly described. A valve pinion, a hollow valve shaft disposed in a state inserted into a shaft portion of the valve pinion, and a torsion bar fixed in the valve shaft in an inserted state and spline-fitted to the valve pinion. It is composed of

When a driver rotates a steering wheel, a valve shaft is rotated via a steering main shaft, an intermediate shaft, and the like. Therefore, the valve pinion rotates via the torsion bar, and the rack bar is moved to change the steering angle. At this time, when the torsion bar is twisted with respect to the valve pinion, the valve shaft rotates extra by the amount of the twist, and a hydraulic pressure difference is generated between the right chamber and the left chamber of the power cylinder. As a result, the steering force by the driver is assisted.

[0004] Conventionally, the above-described control valve has been assembled to a gear box housing in the following manner. First, a support bearing (ball bearing) is attached to the upper end of the valve body of the control valve that has been assembled in advance. Next, a bearing fixing nut for retaining the support bearing is screwed into the upper end of the valve body. Then
Insert the control valve with the support bearing into the gearbox housing. Thereafter, a cap assembly that supports the outer race of the support bearing and seals the inner and outer peripheries is assembled to the gear box housing.

However, in the case of the above-described conventional assembling procedure, the following problems occur. That is, since the outer diameter of the support bearing is larger than the outer diameter of the control valve, when inserting the control valve in which the support bearing is pre-installed into the gear box housing,
A guide (jig) for smoothly inserting the control valve into the gear box housing cannot be used. For this reason, there is a possibility that the seal ring fitted on the outer periphery of the valve body of the control valve is caught by the edge of the insertion opening of the gear box housing and is damaged. If the seal ring is broken, the hydraulic control circuit may not be properly partitioned, which may affect the valve characteristics of the control valve.
Therefore, conventionally, the work of assembling the control valve to the gear box housing must be performed with great care, which is one of the factors that lowers the workability.

[0006] On the other hand, the lower end of the valve shaft of the control valve is spline-fitted to the inner peripheral surface of the valve pinion on the bottom (end) side of the valve body. Here, the upper end of the female spline on the inner peripheral surface on the bottom side of the valve body is usually formed by intermittent cutting. At this time, burrs are generated on the slope of the female spline, but if such burrs are left unattended, it leads to a decrease in the relative rotation angle of the valve shaft with respect to the valve pinion (ie, the operating angle of the control valve varies),
As a result, the valve characteristics of the control valve may be affected.

However, since the female spline itself is formed on the inner peripheral surface side of the bottom of the valve body,
Deburring is very difficult, and it is not possible to sufficiently remove burrs even by shot blasting or the like which strikes metal particles at high speed. Therefore, as another method, it is possible to increase the design operating angle in advance in anticipation of a decrease in the operating angle of the control valve due to burrs, but in this case, the torsion angle of the torsion bar increases, so the torsion angle increases. Bar fatigue is a concern, and there is a limit.

[0008] In summary, in the case of the conventional method, there is a possibility that the seal ring may be damaged due to the assembling procedure, and the burr may not be sufficiently removed due to the processing method. However, there is a possibility that the valve characteristics of the control valve are degraded by these.

In view of the above, it is an object of the present invention to provide a method of assembling a control valve for a power steering device and a method of reducing a variation in an operating angle, which can improve valve characteristics.

[0010]

According to a first aspect of the present invention, there is provided a method for assembling a control valve for a power steering apparatus according to the present invention, wherein an insertion guide jig is mounted at a predetermined position of an opening of a gear box housing. A first step of inserting a control valve for a power steering device having a seal member fitted on an outer peripheral portion thereof into a gear box housing using a jig, and removing an insertion guide jig;
A second step of assembling a support bearing for rotatably supporting the outer periphery of the control valve to the gear box housing, and rotating or rotating the control valve to change the steering angle by rotating about the axis; A third step of screwing a bearing fixing nut for retaining the support bearing into the control valve with the moving rudder angle changing element constrained, and supporting the outer race of the support bearing and connecting the control valve and the gearbox housing to each other. A fourth method for assembling a cap assembly for sealing the gap between the openings of the gear box housing.
And a step of:

According to a second aspect of the present invention, a valve body in which a female spline is formed on the inner periphery on the bottom side of the hollow shaft core by cold forging and cutting, and is coaxially extended from the valve body. A valve gear composed of a steering gear, a pipe-shaped valve shaft formed with a male spline fitted into a female spline on the outer periphery of the insertion direction side end inserted into the hollow shaft core of the valve body,
A torsion bar that is inserted into the hollow shaft core of the valve shaft and is coupled to the valve shaft and the valve gear. In the neutralizing process of a control valve in which the male spline of the valve shaft is fitted to the female spline of the valve body and the valve shaft and the torsion bar are not connected, or the valve shaft and the torsion bar are connected In the state where the control valve is assembled, a torque larger than that applied during normal steering is applied to the valve shaft to crush the burr generated on the female spline with the male spline, or the hollow of the valve body. Insert the valve shaft into the shaft core Instead of, by inserting the special tool of high hardness male spline corresponding to the male spline of the valve shaft is formed in a hollow axial core portion of the valve body,
It is characterized in that burrs generated on the female splines are crushed by the male splines of the dedicated jig by applying a torque larger than the torque applied during normal steering to the dedicated jig.

According to the first aspect of the present invention, in the first step, first, the insertion guide jig is mounted at a predetermined position of the opening of the gear box housing. Next, using the insertion guide jig, the control valve for the power steering device having the seal member fitted to the outer peripheral portion is inserted into the gear box housing. At the time of the first step, no support bearing is attached to the control valve.

Next, in a second step, the insertion guide jig is removed, and a support bearing is assembled between the outer peripheral portion of the control valve and the gear box housing. Thus, the outer peripheral portion of the control valve is rotatably supported by the gear box housing.

Next, in a third step, in a state where the steering angle changing element which rotates or moves so as to change the steering angle by rotating the control valve around the axis is restrained,
Screw the bearing fixing nut for retaining the support bearing onto the control valve. In other words, the reaction force support of the tightening torque of the bearing fixing nut is performed by restricting the steering angle changing element.

Next, in a fourth step, the cap assembly is assembled to the opening of the gear box housing. Thus, the outer race of the support bearing is supported, and the space between the control valve and the gear box housing is sealed.

As described above, in the present invention, the control valve is assembled to the gear box housing before the support bearing is assembled, and at this time, the insertion guide jig is attached to a predetermined position of the opening of the gear box housing. Therefore, the control valve is assembled into the gear box housing while being reliably and smoothly guided by the insertion guide jig. Therefore, it is possible to prevent the seal member fitted to the outer peripheral portion of the control valve from being caught and damaged by the edge of the opening of the gear box housing.

According to the second aspect of the present invention, the torsion bar is inserted into the hollow shaft core of the valve body of the valve gear, and the torsion bar and the valve gear are connected. Next, a pipe-shaped valve shaft is inserted between the valve body and the torsion bar. At this time,
A male spline formed on the outer periphery of the end in the insertion direction of the valve shaft is fitted to a female spline formed by cold forging and cutting on the inner periphery on the bottom side of the valve body. Next, the torsion bar and the valve shaft are connected, and the control valve is assembled.

In the above-described assembling procedure, usually, when the male spline of the valve shaft is fitted to the female spline of the valve body and the valve shaft and the torsion bar are not connected, that is, when the valve shaft is When in a free state around the axis, the valve shaft is swung around the axis to determine the neutral position of the control valve.

Here, in the present invention, in the neutralizing step of the control valve, a torque larger than the torque applied during normal steering is applied to the valve shaft, so that the female spline of the valve body is cut by cutting the end. The generated burrs will be crushed by male splines on the valve shaft. Therefore, there is almost no variation in the relative rotation angle of the valve shaft with respect to the valve body (that is, the operation angle of the control valve), and the operation angle becomes uniform. In addition to the burring in the neutralizing step of the control valve, this may be performed in a state where the valve shaft and the torsion bar are connected and the control valve is assembled.

Alternatively, unlike the above, instead of inserting the valve shaft into the hollow shaft core of the valve body,
Insert a high-hardness dedicated jig with a male spline corresponding to the male spline of the valve shaft into the hollow shaft core of the valve body, and perform the same operation to specially remove the burr of the female spline of the valve body. You may make it crush with the male spline of a tool.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment A first embodiment of the present invention will be described below with reference to FIGS.

FIGS. 1 to 4 show an assembling procedure relating to a steering gear box in a rack and pinion type power steering apparatus.

As shown in these figures (particularly in FIG. 1), the gear box housing 10 includes a cylindrical valve accommodating portion 12 which is disposed obliquely with a longitudinal direction substantially in the vertical direction of the vehicle, and a valve accommodating portion. And a cylindrical rack accommodating portion 14 communicated with the valve accommodating portion 12 and disposed substantially in the vehicle width direction as a longitudinal direction, and communicated with a portion where the valve accommodating portion 12 and the rack accommodating portion 14 intersect. A cylindrical guide accommodating section (not shown) arranged with the direction orthogonal to the longitudinal direction.

Still referring to the valve housing 12, the valve housing 12 includes an upper portion 12A, an intermediate portion 12B, a lower portion 12C, and a lower end portion 12D which are communicated with each other in the axial direction.
It is composed of such parts. Valve housing 1
2, upper part 12A, middle part 12B, lower part 12C,
The inner diameter of the lower end portion 12D is reduced in this order. Of these, the lower portion 12C and the lower end portion 12D
Is formed in the wall of the rack accommodating portion 14.

A step 16 for fitting a seal is formed at a connection portion between the intermediate portion 12B and the lower portion 12C, and a lower oil seal 18 is fitted to this portion. A bearing pedestal step 20 is formed at a connection portion between the intermediate portion 12B and the upper portion 12A, and a cap insertion regulating step 22 and a female screw 24 are formed on an inner peripheral surface of the upper end 12A on the opening end side. Are formed adjacent to each other in the axial direction. Further, tubes 26 and 28 are connected to predetermined positions of the intermediate portion 12B and the upper portion 12A, respectively, and communicate with right and left chambers of a power cylinder (not shown) and allow oil to flow according to a steering direction by a driver.

As shown in FIG. 4, a control valve 30 is accommodated in the above-described valve accommodating section 12, and the control valve 30 will be briefly described below. Note that FIG. 5, which is a drawing for a second embodiment described later, shows a longitudinal sectional structure of the control valve 30.
Please refer to it as appropriate.

As shown in these figures, a control valve 30 is formed integrally with a bottomed cylindrical valve body 32 disposed at the outermost periphery and a lower end of the valve body 32 and has a pinion at the outer periphery. A valve pinion 36 including a pinion shaft 34 having teeth 34A formed thereon
A hollow shaft (pipe-shaped) valve shaft 38 inserted into the hollow shaft core of the valve body 32, and a torsion bar 40 inserted into the hollow shaft core of the valve shaft 38.
And is constituted as a main part.

The valve pinion 36, the valve shaft 38, and the torsion bar 40 are all coaxially arranged. The lower end of the torsion bar 40 is spline-fitted to the bottom of the valve body 32, and the upper end of the torsion bar 40 is connected to the valve shaft 38 by a fixing pin 42 (see FIG. 5) penetrating in the radial direction. . Thereby, the control valve 30 is assembled. Further, the valve shaft 38
The upper needle bearing 44
The lower needle bearing 46 is vertically spaced apart, and plays a role in smoothing the relative rotation of the valve shaft 38 with respect to the valve body 32.

A plurality of hydraulic control ports 48 to 56 are formed at predetermined positions on the peripheral wall of the valve body 32 and at predetermined positions in the axial direction of the valve shaft 38.
Further, four seal rings 58 as “seal members” made of an elastic material such as a resin are fitted on the outer peripheral portion of the valve body 32 at predetermined intervals in the axial direction.

When the control valve 30 having the above structure is housed in the valve housing portion 12, the valve pinion 3
6, the pinion teeth 34A of the pinion shaft 34 are disposed in the lower portion 12C of the valve housing portion 12, and the pinion shaft 3
The lower end of 4 is rotatably supported by a needle bearing 60 pressed into the lower end 12D of the valve housing 12.

A lower oil seal 18 fitted to the seal fitting step 16 is pressed against the outer peripheral surface of the lower end of the valve body 32. Thereby, the space between them is sealed. Furthermore, valve body 3
A plurality of seal rings 58 fitted to the outer peripheral portion of the valve housing 2 are pressed against the inner peripheral surface of the intermediate portion 12B of the valve housing portion 12, whereby the hydraulic control circuit is partitioned in the axial direction.

Further, on the outer periphery of the upper end of the valve body 32, a bearing pedestal step 62 is formed at a position facing the aforementioned bearing pedestal step 20, and these bearing pedestal steps 20, 62 are formed on the bearing pedestal steps 20, 62. Outer race 6 of ball bearing 64 as "supporting bearing"
6. The inner race 68 (see FIG. 3) is lightly press-fitted. A male screw 70 is formed just above the bearing pedestal step 62 in the valve body 32, and a bearing fixing nut 72 that functions to prevent the inner race 68 of the ball bearing 64 from coming off is screwed into the male screw 70. Have been.

A cap assembly 74 is mounted on the open end of the upper portion 12A of the valve housing 12. The cap assembly 74 generally includes a substantially cylindrical cap body 78 having a shaft insertion hole 76 formed in a shaft core, and an O-ring 80 fitted at a predetermined position on an outer peripheral portion of the cap body 78. , An upper oil seal 82 fitted around the shaft insertion hole 76 of the cap body 78.

Supplementally, the shaft core of the cap body 78 in which the shaft insertion hole 76 is formed is formed in a hexagonal prism shape for inserting a tool, and an annular groove 84 is formed in the outer periphery thereof. In addition, instead of making the axis of the cap body 78 a hexagonal column, a hexagonal hole may be formed in the outer periphery of the upper end of the cap body 78. On the outer periphery of the cap body 78, a contact step 86 and a male screw 88 are formed in this order below the O-ring 80. Further, the lower end of the cap body 78 is in contact with the upper end of the outer race 66 of the ball bearing 64 described above. In other words, the outer race 66 of the ball bearing 64 is supported by the lower end of the cap body 78. A plurality of notches 90 for oil distribution are formed at the lower end of the cap body 78, and hatching is not shown in FIG. 4 because a cross section is taken at the position where these notches 90 are formed. .

When the male screw 88 of the cap assembly 74 is screwed into the female screw 24 of the upper portion 12A of the valve housing 12, the O-ring 80 is pressed against the inner peripheral surface of the upper portion 12A and the lower oil seal 18 is pressed. It is pressed against the outer peripheral surface of the valve shaft 38.

Further, the above-described cap assembly 74
The upper end portion of the valve shaft 38 that penetrates the shaft insertion hole 76 and is disposed in a protruding state is connected to the intermediate shaft via a universal joint (not shown). The intermediate shaft is connected to a steering wheel to which a steering force is input via a steering main shaft.

On the other hand, the gear box housing 1 described above
A rack bar 92 as a "steering angle changing element" is accommodated in the rack accommodating portion 14 at 0 so as to be movable in the axial direction. Rack teeth 92A that mesh with the pinion teeth 34A are formed in a predetermined range in the axial direction of the rack bar 92.
Further, a power piston (not shown) is fixed to a predetermined position in the axial direction of the rack bar 92 (between the connection portions with the tubes 26 and 28). A tie rod end connected to a steering knuckle via a ball joint is attached to both ends in the longitudinal direction of the rack bar 92.

Further, a rack guide or the like for urging the rack bar 92 in a direction in which the rack teeth 92A of the rack bar 92 mesh with the pinion teeth 34A of the pinion shaft 34 is housed in the guide housing portion of the gear box housing 10 described above. Have been.

Next, an assembling procedure of the control valve 30 and the like will be described with reference to FIGS.

First, as shown in FIG. 1, the lower end 1 of the valve housing 12 in the gearbox housing 10 is provided.
The needle bearing 60 is press-fitted in 2D in advance, and the lower oil seal 18 is previously fitted in the seal fitting step 16 formed in the connection portion between the intermediate portion 12B and the lower portion 12C. At this time, the rack bar 9 is inserted into the rack accommodating portion 14 of the gear box housing 10.
2 are already contained.

Next, as shown in FIG. 2, a step portion 20 for the bearing pedestal at the upper portion 12A of the valve housing portion 12 is formed.
, A cylindrical insertion guide jig 94 is mounted. The inner diameter of the insertion guide jig 94 matches the inner diameter of the intermediate portion 12B of the valve accommodating portion 12, and its upper end 94A.
Is constituted by a curved surface having a predetermined radius of curvature.

Then, using the insertion guide jig 94, the control valve 30 having the four seal rings 58 fitted on the outer peripheral portion in advance is inserted into the valve housing 12. At this time, the four seal rings 58 fitted to the outer peripheral portion of the control valve 30 are guided by the upper end portion 94A of the insertion guide jig 94 so that the diameter is gradually and smoothly reduced. At this time, the ball bearing 64 is not mounted on the control valve 30. The steps so far correspond to the “first step” of the present invention.

Next, as shown in FIG. 3, the insertion guide jig 94 is removed from the upper portion 12A of the valve housing portion 12. Next, the outer race 6 of the ball bearing 64
6 is the bearing pedestal step 20 of the valve housing 12,
The inner race 68 is lightly pressed into the bearing pedestal step 62 on the valve body 32 side. The steps so far correspond to the “second step” of the present invention.

Next, the end of the rack bar 92 is attached to the holder 96.
The bearing fixing nut 72 is screwed into the male screw 70 of the valve body 32 while being held (restricted). In other words, by utilizing the fact that the pinion teeth 34A of the control valve 30 and the rack teeth 92A of the rack bar 92 mesh with each other, the end of the rack bar 92 is held by the holding tool 96, thereby tightening the bearing fixing nut 72. It receives the reaction force of torque. As a result, the control valve 30 is rotatably supported by the needle bearing 60 and the ball bearing 64.
The steps so far correspond to the “third step” of the present invention.

Next, as shown in FIG. 4, a tool (not shown) is fitted to the hexagonal column-shaped shaft core of the cap body 78, and the cap assembly 74 is screwed into the upper portion 12A of the valve housing portion 12. . Thereby, the cap body 78
Is in contact with the outer race 66 of the ball bearing 64, and the outer race 66 is supported. Also,
An O-ring 80 seals a gap between an outer peripheral surface of the cap body 78 and an inner peripheral surface of the upper portion 12A of the valve accommodating portion 12, and an upper oil seal 82 forms a shaft core of the cap body 78 and an outer peripheral surface of the valve shaft 38. Is sealed. The steps so far correspond to the “fourth step” of the present invention.

In the rack-and-pinion type power steering device assembled in the above-described procedure, when a steering wheel (not shown) is rotated, the valve shaft 38 rotates around the axis via the steering main shaft and the intermediate shaft. Is rotated. Thereby, the valve pinion 36 rotates via the torsion bar 40, and the rack bar 92 is linearly moved to change the steering angle. If the torsion bar 40 is twisted with respect to the valve pinion 36 at this time, the valve shaft 38 rotates extra by the amount of the twist, and a hydraulic pressure difference occurs between the right chamber and the left chamber of the power cylinder. As a result, the steering force of the steering wheel by the driver is assisted.

As described above, in the present embodiment, before assembling the ball bearing 64 to the control valve 30, the control valve 30 is assembled to the valve housing 12 of the gearbox housing 10. The insertion guide jig 94 is attached to the bearing pedestal step 20 in the upper part 12A of the gear box housing 10 while securely and smoothly guiding the control valve 30 by the insertion guide jig 94. 12 can be assembled. For this reason, the seal ring 58 fitted on the outer peripheral portion of the control valve 30 is
Can be prevented from being caught on the edge of the device. As a result, the valve characteristics of the control valve 30 can be improved.

In this embodiment, the present invention is applied to a steering gear box in an R & P (rack and pinion) power steering apparatus. However, the present invention is not limited to this, and an RBS (recirculating ball screw) The present invention may be applied to a steering gear box in the power steering device of (1). In this case, the reaction force support of the tightening torque of the bearing fixing nut 72 may be performed by restraining the pitman arm or the like. Second Embodiment Next, a second embodiment of the present invention will be described with reference to FIGS. Note that the same components as those of the above-described first embodiment are denoted by the same reference numerals, and description thereof is omitted.

FIG. 5 shows a longitudinal sectional structure of the control valve 30 described in the first embodiment.
FIG. 6 is an enlarged cross-sectional structure taken along line 6-6 in FIG.

As shown in these figures, eight female splines 100 are formed at equal intervals on the inner peripheral side of the bottom of the valve body 32 in the valve pinion 36 as the above-mentioned "valve gear". Correspondingly, eight male splines 102 are also formed at equal intervals on the outer peripheral side of the lower end of the valve shaft 38. And these male splines 102 are female splines 100
Is fitted (freely fitted) to the valve shaft 38.
And the bottom of the valve body 32 are connected.

As shown in FIG. 6, the slope 100A of the female spline 100 and the slope 1 of the male spline 102
A predetermined gap 104 is formed between the gap 102A and 02A. The presence of the gap 104 allows the valve shaft 38 to rotate relative to the valve body 32 within a predetermined angle range (until the slope 102A of the male spline 102 comes into contact with the slope 100A of the female spline 100). The control valve 30
Operating angle. That is, these female splines 100
And control valve 3 by male spline 102
The operation angle of 0 is mechanically determined and the torsion bar 40 is prevented from being fatigued due to excessive torsion. In this sense, the female spline 100 and the male spline 102 are also referred to as “manual stoppers”. is there.

In the above configuration, the pinion shaft 34 of the valve pinion 36 corresponds to the "steering gear" according to the present invention.

Next, the operation and effect of this embodiment will be described.

First, a procedure for assembling the control valve 30 itself will be described. First, the torsion bar 40 is inserted into the hollow shaft core of the valve body 32 of the valve pinion 36, and the lower end of the torsion bar 40 is spline-fitted to the bottom of the valve body 32. Next, a pipe-shaped valve shaft 38 is inserted between the valve body 32 and the torsion bar 40, and the male spline 102 of the valve shaft 38 is loosely fitted to the female spline 100 of the valve body 32. Next, a fixing pin 42 is inserted into the upper end of the torsion bar 40 and the upper end of the valve shaft 38 in the radial direction (the direction perpendicular to the axis), and the two are joined. Thereby, the control valve 30 is assembled.

Here, the female spline 100 on the valve body 32 side is formed by cold forging and cutting the bottom of the valve body 32. Therefore, FIG.
As shown in (A), the slope 10 of the female spline 100
The burr 106 is easily generated at 0A, and if the burr 106 is left as it is, the operating angle of the control valve 30 may be insufficient, and the operating angle varies depending on the amount of the burr 106.

Therefore, in this embodiment, the burrs 106 are crushed and removed as follows. That is, usually, the valve body 32 and the torsion bar 40
At the stage where the valve shaft 38 is inserted and the male spline 102 is loosely fitted to the female spline 100 (at this stage, the fixing pin 42 has not been inserted yet, and the valve shaft 38 is free around the axis. ), The neutral position of the control valve 30 is obtained by swinging the valve shaft 38 around the axis.

In the present embodiment, a torque larger than the torque applied during normal steering is applied to the valve shaft 38 in both the clockwise direction and the counterclockwise direction by utilizing the neutralizing process. As a result, as shown in FIGS. 7B and 7C, the male spline 10 of the valve shaft 38 is formed.
The second slope 102A is strongly pressed against the slope 100A of the female spline 100 of the valve body 32, and the female spline 100
The burr 106 generated on the slope 102A is crushed.

Therefore, there is almost no variation in the relative rotation angle of the valve shaft 38 with respect to the valve body 32 (that is, the operation angle of the control valve 30), and the operation angle becomes uniform. As a result, according to the present embodiment, the valve characteristics of the control valve 30 can be improved.

Further, in the present embodiment, a method of crushing the burr 106 using the neutralizing step is devised, so that the step of checking the operating angle of the control valve 30 which is an actual product can also be performed. Therefore, there is an advantage that there is no need to largely change the equipment and processes in the factory line from the current state.

In the present embodiment, the method of crushing the burr 106 in the neutralizing step of the control valve 30 is employed. However, the present invention is not limited to this, and the valve shaft 38 and the torsion bar 40 are connected by the fixing pin 42 to control the control. In a state where the valve 30 is assembled, the burr 106 may be similarly crushed. Even if it does in this way, since the rotation angle of the valve shaft 38 rotated to crush the burr 106 is within the range of the design operation angle, excessive torsion of the torsion bar 40 does not occur.

Alternatively, instead of inserting the valve shaft 38 into the hollow shaft core of the valve body 32, a high-hardness dedicated jig having a male spline corresponding to the male spline 102 of the valve shaft 38 is provided. 32
Of the female spline 100 of the valve body 32 by inserting the same into the hollow shaft core portion and performing the same operation.
06 may be crushed by a male spline of a special jig.

In the present embodiment, the present invention is applied to a steering gear box in an R & P (rack and pinion) power steering apparatus. However, the present invention is not limited to this, and an RBS (recirculating ball screw) The present invention may be applied to a steering gear box in the power steering device of (1).

[0063]

As described above, the method for assembling a control valve for a power steering apparatus according to the present invention according to the first aspect of the present invention includes assembling the control valve to the gear box housing before assembling the support bearing. In addition, at that time, the insertion guide jig is mounted at a predetermined position of the opening of the gear box housing, so that the seal member fitted to the outer peripheral portion of the control valve is caught by the edge of the opening of the gear box housing. Damage can be prevented, and as a result, there is an excellent effect that the valve characteristics of the control valve can be improved.

According to a second aspect of the present invention, there is provided a method for reducing a variation in the operating angle of a control valve for a power steering apparatus according to the present invention. In the neutralizing step of the control valve in a non-coupled state, or in a state in which the valve shaft and the torsion bar are in a coupled state and the control valve is assembled, a torque larger than the torque acting during normal steering is applied to the valve. By acting on the shaft, burrs generated on the female spline are crushed by the male spline, or a male spline corresponding to the male spline of the valve shaft is formed instead of inserting the valve shaft into the hollow shaft core of the valve body. Dedicated jig with high hardness Since it was inserted into the hollow shaft core of Dee, and a torque larger than the torque acting during normal steering was applied to the special jig, the burr generated on the female spline was crushed by the male spline of the special jig, There is almost no variation in the operating angle of the valve shaft with respect to the valve body, and as a result, there is an excellent effect that the valve characteristics of the control valve can be improved.

[Brief description of the drawings]

FIG. 1 is an explanatory view of an assembling procedure relating to a steering gear box in a rack and pinion type power steering apparatus according to a first embodiment, and is a longitudinal sectional view showing a state in which a control valve is not attached to a gear box housing. It is.

FIG. 2 is a longitudinal sectional view corresponding to FIG. 1, showing a state in which an insertion guide jig is mounted from a state shown in FIG. 1 and a control valve is inserted into a valve housing portion.

FIG. 3 is a longitudinal sectional view corresponding to FIG. 2, showing a state where the insertion guide jig is removed from the state shown in FIG. 2 and a ball bearing and a bearing fixing nut are screwed together.

FIG. 4 is a longitudinal sectional view corresponding to FIG. 2, showing a state where the cap assembly is assembled from the state shown in FIG. 3;

FIG. 5 is a longitudinal sectional view of a control valve in a rack and pinion type power steering device according to a second embodiment.

6 is a cross-sectional view of the control valve shown in FIG. 5, taken along line 6-6.

FIG. 7 is an explanatory diagram for explaining the operation of the second embodiment.

[Explanation of symbols]

 10 Gear Box Housing 30 Control Valve 32 Valve Body 34 Pinion Shaft (Steering Gear) 36 Valve Pinion (Valve Gear) 38 Valve Shaft 40 Torsion Bar 58 Seal Ring (Seal Member) 64 Ball Bearing (Support Bearing) 66 Outer Race 72 Bearing Fixing Nut 74 Cap assembly 92 Rack bar (rudder angle changing element) 94 Insertion guide jig 96 Holder 100 Female spline 102 Male spline 106 Burr

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Shoji Nagasume 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation F-term (reference) 3C030 CC07 3D033 FD07 3H053 AA26 AA35 BC01 BD02 BD03 DA11

Claims (2)

[Claims] 1. A control valve for a power steering device in which an insertion guide jig is mounted at a predetermined position of an opening of a gear box housing, and a seal member is fitted to an outer peripheral portion using the insertion guide jig. A second step of removing the insertion guide jig and assembling a support bearing for rotatably supporting the outer periphery of the control valve to the gearbox housing between the first step and the control; A third step of screwing a bearing fixing nut for retaining the support bearing into the control valve in a state in which the steering angle changing element that rotates or moves to change the steering angle by rotating the valve around the axis is restrained; Supports the outer race of the support bearing and controls valve and gearbox housing And a fourth step of assembling a cap assembly for sealing the gap between the gearbox housing and the opening in the gear box housing. 2. A valve gear comprising a valve body in which a female spline is formed on a bottom inner side of a hollow shaft core by cold forging and cutting, and a steering gear coaxially extended from the valve body. A pipe-shaped valve shaft which is inserted into the hollow shaft core of the valve body and has a male spline fitted on the female spline on the outer periphery of the insertion direction side, and inserted into the hollow shaft core of this valve shaft And a torsion bar coupled to the valve shaft and the valve gear, wherein the male spline of the valve shaft is a female body of the valve body. The valve shaft and the torsion bar are not connected to each other with the spline fitted. In the neutralizing step of the control valve, or in a state where the valve shaft and the torsion bar are connected and the control valve is assembled, a torque larger than that applied during normal steering is applied to the valve shaft, and the female A male spline is used to crush the burrs generated on the spline. Alternatively, instead of inserting the valve shaft into the hollow shaft core of the valve body, a dedicated high-hardness treatment in which a male spline corresponding to the male spline of the valve shaft is formed. The tool is inserted into the hollow shaft core of the valve body, and a torque larger than the torque applied during normal steering is applied to the special jig to crush the burr generated on the female spline with the male spline of the special jig. Characteristic method of reducing operating angle variation of control valve for power steering device .