WO2016204023A1 - Ball circulation tube for ball screw, ball screw, and ball screw manufacturing method - Google Patents

Abstract

Provided is a ball circulation tube for a ball screw, which is provided with a scoop-up section that can reduce the influence of machining errors. This ball circulation tube (4) is formed of, as discrete parts: a pair of scoop-up parts (43A, 43B) each having a ball scoop-up section (4a); and a circulation channel part (41) having a ball circulation channel (4j).

Description

Ball circulation tube for ball screw, ball screw and ball screw manufacturing method

The present invention relates to an external circulation type ball screw.

In the external circulation type ball screw, the ball circulation tube is exposed and arranged on the outer surface of the nut screwed to the screw shaft via a large number of balls, and the ball in the rolling path is wound by this ball circulation tube. It is a structure that circulates after guiding it to the outside of the nut. This type of ball circulation tube has, as two functional parts, a ball scooping part for scooping up the ball from the rolling path and a ball circulation path for circulating the ball, located at the end of the ball circulation tube.
The ball scooping-up portion is known as a portion greatly related to the operability of the ball. For example, if there is a step at the position where the ball scooping section and the rolling path face each other due to the effects of processing errors, the ball collides with the ball scooping section and the ball scooping section is damaged or vibrated. And noise may be generated. Therefore, for example, in the technique described in Patent Document 1, both ends of the ball circulation tube are attached to the nut via a pair of tube guides to improve operability.

JP 2004-108454 A

However, the ball scooping portion is a portion that greatly affects the operability even if there is a slight processing error. Therefore, if the shape of the ball scooping part is complicated, it becomes more susceptible to processing errors. Further, even when the ball circulation tube is formed as a molded product, it is sufficient if there is a production amount commensurate with it. However, when the molded product is used for the other product, the cost advantage is reduced.
Therefore, as disclosed in Patent Document 1, even when a structure that is attached to a nut via a tube guide is adopted for both ends of the ball circulation tube, There can be a step between the rolling path and there is room for consideration in reducing the effects of machining errors.

Therefore, an object of the present invention is to provide a ball circulation tube for a ball screw, a ball screw, and a method for manufacturing the ball screw, each having a scooping portion that can reduce the influence of a processing error.

In order to solve the above-described problems, a ball circulation tube for a ball screw according to an aspect of the present invention includes a screw shaft having a spiral thread groove on an outer peripheral surface, and a nut having a spiral thread groove on an inner peripheral surface. And a ball screw having a plurality of balls disposed in a rolling path formed by these thread grooves, and is mounted on a tube mounting portion of the nut so that the ball circulates on an outer surface of the nut. A ball circulation tube that scoops up the ball of the rolling path from the ball scooping part on one end side and returns it from the ball scooping part on the other end side through the ball circulation path, The pair of scooping parts and the circulation path part having the ball circulation path are formed of separate parts.

According to the ball circulation tube for a ball screw according to one aspect of the present invention, the pair of scooping parts and the circulation path part are formed of separate parts. The relative posture can be adjusted individually. For example, the mounting posture of each scooping component can be individually adjusted in a state where only a pair of scooping components are attached to the tube mounting portion of the nut without mounting the circulation path components. Therefore, if there is an absolute processing error in the ball scooping part of each scooping part or a relative processing error in the ball scooping part between a pair of scooping parts, In addition, the influence of processing errors can be reduced as compared with a ball circulation tube in which a pair of ball scooping portions and a ball circulation path portion are integrally formed.
In addition, according to the ball circulation tube for ball screw according to one aspect of the present invention, the pair of scooping parts and the circulation path parts are composed of separate parts. The stuffing operation can be performed with only the scooping parts attached to the tube mounting portion of the nut. In addition, since the stuffing operation can be performed with the scooping component attached to the nut, there is an effect of preventing the ball from entering the rolling path in the direction outside the circulation path.

Here, in the ball circulation tube for a ball screw according to an aspect of the present invention, the scooping component is formed from a cylindrical member having a center axis as a track drawn by the center of the ball circulating in the scooping component, It is preferable to have a cylindrical shape and an upper surface that allow rotation around the central axis when mounted on the tube mounting portion.
With such a configuration, when the nut is mounted, the scooping component can freely move in the direction of rotation around its own axis. For this reason, the rolling-up component itself is rotated to the position where the magnitude of the force of collision with the ball is the smallest due to the collision force between the ball and the scooping-up portion by the leveling rotation after filling the rolling path. Can do. Therefore, it is more suitable for mounting scooping parts so as to reduce the influence of machining errors during the leveling operation.

Further, in the ball circulation tube for a ball screw according to one aspect of the present invention, an annular elastically deformable in an axial direction interposed between the upper surface of the scooping component and the lower surface of the circulation path component. It is preferable to have an elastic part.
With such a configuration, since the annular elastic part interposed coaxially between the scooping part and the circulation path part can be elastically deformed in the axial direction, the scooping part and the circulation path part can be obtained by this elastic part. It is suitable for absorbing the machining error in the axial direction and the error of the tightening amount at the time of fixing, and fixing the scooping part and the circulation path part with an excessive and insufficient tightening force.

Further, in the ball circulation tube for ball screw according to one aspect of the present invention, the scooping component and the elastic component are either one of the other surface with respect to the concave portion formed on one of the opposing surfaces. It is preferable to have a concavo-convex shape into which the convex portions formed on the surface of the mate.
With such a configuration, it is preferable to improve the assembling property by preventing the misalignment around the respective axes by providing the concave and convex shapes to be fitted to each other on the opposing surfaces and combining each other. It is.

In addition, the scooping component and the elastic component may be configured such that the recess formed on one of the surfaces has a dimension around the central axis of the convex portion formed on the other surface. It is preferable that it is formed wider than the surrounding dimensions.
With such a configuration, the concave part formed on one surface of the scooping part and the elastic part has a dimension around the central axis, and the central axis of the convex part formed on the other surface Since it is wider than the surrounding dimensions, the mounting posture of each scooping part around the central axis can be individually adjusted (hereinafter also referred to as “alignment”), and each scooping shape has an uneven shape that fits together. The rotatable range around the central axis of the raised component can be restricted. Therefore, it is more suitable for facilitating positioning while providing alignment to the scooping component.

Moreover, in the ball circulation tube for a ball screw according to an aspect of the present invention, the scooping component and the tube mounting portion of the nut are arranged on the opposing surface with respect to any one convex portion. The concave portion formed on one of the surfaces has a concave-convex shape to which the concave portion is fitted, and the size around the central axis is the size of the convex portion formed on the other surface around the central axis. It is preferable that it is formed wider than the dimension.
With such a configuration, the concave part formed on one surface of the scooping part and the tube mounting portion of the nut is the convex part formed on the other surface with the dimension around the central axis. This is more suitable for facilitating positioning while keeping the scooping parts aligned.

In order to solve the above problems, a ball screw according to an aspect of the present invention includes a screw shaft having a spiral thread groove on an outer peripheral surface, a nut having a spiral thread groove on an inner peripheral surface, and these A plurality of balls disposed in a rolling path formed by a thread groove, and one end of the ball of the rolling path that is mounted on a mounting surface of the nut and circulates on the outer surface of the nut. A ball circulation tube that scoops up from the ball scooping portion on the side and returns from the ball scooping portion on the other end side through a ball circulation path, and the ball circulating ball according to one aspect of the present invention is used as the ball circulation tube It has a circulation tube.
According to the ball screw according to the aspect of the present invention, since the ball screw tube ball circulation tube according to the aspect of the present invention is provided, only the pair of scooping parts is attached to the nut without attaching the circulation path parts. In the state, the mounting posture of each scooping component can be individually adjusted. Therefore, even if a relative processing error occurs in the ball scooping portion between the pair of scooping parts, the influence of the processing error can be reduced.

In order to solve the above-mentioned problem, a ball screw manufacturing method according to an aspect of the present invention is a method of manufacturing a ball screw according to any one of the present invention, wherein the pair of scooping up A part is assembled to the tube mounting portion, and a first step of inserting the ball into the rolling path from an upper opening of the pair of scooping parts in the assembled state is included.
According to the ball screw manufacturing method according to one aspect of the present invention, in the first step, the pair of scooping components is assembled to the tube mounting portion of the nut, so that when scooping the nut, the scooping component is rotated about its axis. Can move freely in any direction. Therefore, if there is an absolute processing error in the ball scooping part of each scooping part or a relative processing error in the ball scooping part between a pair of scooping parts, In addition, the influence of processing errors can be reduced. Then, in the assembled state, the ball is inserted into the rolling path from the upper opening of the pair of scooping parts. Therefore, when inserting the ball into the rolling path between the screw shaft and the nut, the ball is lifted up in advance. By mounting the part, the ball can be incorporated so that the ball does not enter in a direction where the ball should not be inserted.

Here, in the ball screw manufacturing method according to one aspect of the present invention, after the first step, the balls are packed in the circulation path components, and the circulation path components packed with the balls are After the second step of assembling the tube mounting portion of the nut from the top of the scooping component, and after the second step, the ball is circulated by rotating the nut or the screw shaft while holding the circulation path component. Thus, it is preferable to include a third step of rotating the scooping component itself around its axis by the force of the ball colliding with the scooping portion of the scooping component.

In such a configuration, in the second step, the balls are packed in the circulation path parts, and the circulation path parts packed with the balls are assembled from the upper part of the pair of scooping parts to the tube mounting portion of the nut. In the state of the second step, the ball of the rolling path is scooped up from the ball scooping portion on one end side so that the ball circulates on the outer surface of the nut, and the ball on the other end side is scooped up through the ball circulation path. It can be returned from the department.
In the third step, the ball is circulated by rotating the nut or the screw shaft while holding the circulation path component, so that the scooping component itself is caused by the force of the ball colliding with the scooping portion of the scooping component. Since it is rotated around the axis, it is possible to rotate around the axis from the part to be picked up to a position where the force with which the ball scooping part collides with the ball is minimized.

Furthermore, in order to solve the said subject, the manufacturing method of the ball screw which concerns on 1 aspect of this invention manufactures the ball screw which concerns on any one aspect (except the aspect which does not interpose an elastic component) among this invention. A first step of assembling the pair of scooping parts to the tube mounting portion and inserting the ball into the rolling path from the upper openings of the pair of scooping parts in the assembled state. And after the first step, the balls are packed in the circulation path parts, and the circulation path parts packed with the balls are placed between the pair of scooping parts and the circulation path parts packed with the balls. In a state where the elastic part is interposed, a second step of assembling the tube mounting portion of the nut from the upper part of the pair of scooping parts, and after the second step, while holding the circulation path part, Na A third step of rotating the scooping component itself around its axis by a force of the ball colliding with a ball scooping portion of the scooping component by rotating the screw shaft or the screw shaft After the third step, a fourth method of fixing the scooping component together with the circulation path component by pressing the circulation path component using a tube presser for fixing the ball circulation tube to the outer surface of the nut. These steps are included.

According to the ball screw manufacturing method according to one aspect of the present invention (except for an aspect in which no elastic part is interposed), in the first step, the pair of scooping parts are assembled to the tube mounting part of the nut. Sometimes the scooping part can be moved freely in the direction of rotation about its axis. Therefore, even if a relative processing error occurs in the ball scooping portion between the pair of scooping parts, the influence of the processing error can be reduced. And, since the ball is inserted into the rolling path in the assembled state, when the ball is inserted into the rolling path between the screw shaft and the nut, the ball is mounted by attaching a scooping part to the nut in advance. The ball can be prevented from entering in a direction that should not be inserted.

In the second step, a ball is packed in the circulation path component, and the circulation path component packed with the ball is interposed between a pair of scooping parts and the circulation path component packed with the ball. In this second step state, the ball of the rolling path is scooped on one end side so that the ball circulates on the outer surface of the nut. It is possible to scoop up from the raising portion and return from the ball scooping portion on the other end side through the ball circulation path.
In the third step, the ball is circulated by rotating the nut or the screw shaft while holding the circulation path component, so that the scooping component itself is caused by the force of the ball colliding with the scooping portion of the scooping component. Since it is rotated around the axis, it is possible to rotate the component itself up to the position where the force that collides with the ball is the smallest, and to rotate around the axis. Accordingly, it is possible to prevent or suppress the operability from being deteriorated due to a collision of an unexpected part of the scooping part due to a processing error of the scooping part, so that the operability can be improved.

After that, in the fourth step, the circuit parts are pressed using a tube presser for fixing the ball circulation tube to the outer surface of the nut, and the scooping parts are fixed together with the circuit parts. As a result, the elastic part interposed between the scooping part and the circulation path part absorbs the machining error in the axial direction of the scooping part and the circulation path part and the tightening amount error at the time of fixing. And the circulation path portion can be fixed at the same time with a sufficient tightening force.

As described above, according to the present invention, it is possible to provide a ball circulation tube for a ball screw, a ball screw, and a ball screw manufacturing method including a scooping portion that can reduce the influence of processing errors.

It is typical explanatory drawing of one Embodiment of the ball screw which concerns on 1 aspect of this invention, and the principal part is partially broken and shown in the same figure. It is explanatory drawing of the nut of FIG. 1, The figure (a) is the top view, (b) is a left view (A arrow directional view). It is explanatory drawing of one Embodiment of the ball | bowl circulation tube which concerns on 1 aspect of this invention, The figure (a) shows the component of a ball | bowl circulation tube in an exploded state, (b) is B in (a). (C) shows the C view in (a). It is a figure explaining the state which mounted the scooping components in the tube mounting part of the nut of FIG. 1, The figure (a) is the top view, (b) is the principal part enlarged view of (a). It is a figure which shows the image which the scooping component rotates around an axis | shaft with the collision force of a ball | bowl, The figure (a) shows the image which the moment which rotates around an axis | shaft by a collision force is applied, The figure (b) The image of the cooperation effect by the elastic part to interpose is shown. It is a figure ((a)-(c)) explaining the effect of the elastic part interposed between the scooping up part and the circulation path part, The figure (a) and (b) is the conventional integrated type. It is a comparative example using a ball circulation tube, and the same figure (c) is an example using one embodiment of a ball circulation tube concerning one mode of the present invention. It is a figure explaining the modification of a scooping component and an elastic component. It is a figure explaining the scooping components of a 1st modification. It is a figure explaining the elastic component of a 1st modification. It is a figure explaining the scooping components of a 2nd modification. It is a figure explaining the elastic component of a 2nd modification. It is a figure explaining the modification of a scooping component and a tube mounting part. It is a figure explaining the scooping up part (illustrated including an elastic part) of the 3rd modification, The figure (a) is a top view, (b) is a front view, (c) is a bottom view. It is a figure explaining the tube mounting part of a 3rd modification, The figure (a) shows the figure corresponding to FIG.2 (b), (b) is D arrow view of the principal part in Fig.14 (a). FIG. 4C is an enlarged view showing a fitting portion between the convex part of the scooping component and the concave part of the countersink hole, and FIG. 4D is a modification of the example shown in FIG. It is a figure explaining the modification of a scooping-up component, an elastic component, and a circulation path component. It is a figure explaining the circuit components of a 4th modification (and a 5th modification), The figure (a) is a front view, (b) is E arrow in (a), (c) is (a ) In F direction. It is a figure explaining the scooping up part of a 4th modification, The figure (a) is a top view, (b) is a front view. It is a figure explaining the elastic component of a 4th modification, The figure (a) is a top view, (b) is a front view. It is a figure explaining the fitting state of the groove | channel of the elastic component in the 4th modification, and the convex part of the scooping-up component. It is a figure explaining the scooping up part of a 5th modification, The figure (a) is a top view, (b) is a front view. It is a figure explaining the elastic component of a 5th modification, The figure (a) is a top view, (b) is a front view.

Hereinafter, embodiments and modifications of the present invention will be described with reference to the drawings as appropriate. The drawings are schematic. For this reason, it should be noted that the relationship between the thickness and the planar dimension, the ratio, and the like are different from the actual ones, and the dimensional relationship and the ratio are different between the drawings. Further, the following embodiments and modifications exemplify apparatuses and methods for embodying the technical idea of the present invention, and the technical idea of the present invention includes the material, shape, The structure, arrangement, and the like are not specified in the following embodiments and modifications.

As shown in FIG. 1, the ball screw 10 includes a screw shaft 1 and a cylindrical nut 2 that is screwed to the screw shaft 1 via a plurality of balls 3. An annular flange 22 is formed at one end of the nut 2. A spiral thread groove 11 is formed on the outer peripheral surface of the screw shaft 1, and a spiral thread groove 21 facing the screw groove 11 of the screw shaft 1 is formed on the inner peripheral surface of the nut 2. A plurality of balls 3 are arranged in the rolling path 7 formed by these thread grooves 11 and 21.
A flat installation surface 23 is formed on the outer peripheral surface of the nut 2, and the ball circulation tube 4 is mounted on the installation surface 23. Two screw holes 24 for attaching the tube presser 5 are formed in the mounting surface 23 (see FIG. 2A), and the ball circulation tube 4 is fixed to the screw hole 24 with bolts 6 on both sides of the tube presser 5. As a result, the mounting surface 23 is mounted.

The ball circulation tube 4 is a substantially U-shaped tube (tube) having a tongue-shaped ball scooping portion 4a for scooping the ball 3 from the rolling path 7 at both ends, and between the ball scooping portions 4a on both sides. Is provided with a ball circulation path 4 j provided so that the ball 3 circulates on the outer surface of the nut 2.
Specifically, as shown in FIG. 2, a pair of tube mounting portions 25 into which the ball scooping portions 4 a at both ends of the ball circulation tube 4 are respectively inserted are provided on the installation surface 23 at two locations separated in the axial direction. . Each tube mounting portion 25 is formed corresponding to the position where the ball 3 is lifted, and the angle formed by the line connecting the centers of the pair of tube mounting portions 25 and the axis of the nut 2 is a predetermined inclination angle. To be processed.

Each tube mounting portion 25 has a through hole 26 slightly larger than the diameter of the ball 3 and a counterbore hole 27 having a diameter larger than the through hole 26 by the thickness of the ball circulation tube 4. The through hole 26 is machined from a direction perpendicular to the installation surface 23 of the nut 2, passes through the thick part of the nut 2, and communicates with the rolling path 7. Further, each tube mounting portion 25 is provided with a long hole-shaped mounting groove 28 in which the concave R portion 4r of the tube in the ball circulation path 4j shown in FIG. 1 fits along the predetermined inclination angle. . The mounting groove 28 is formed in a convex arc shape that follows the inwardly bent shape of the concave R portion 4r shown in FIG.

Here, as shown in an exploded view of the component parts in FIG. 3, the ball circulation tube 4 is a circulation having a pair of scooping parts 43A and 43B each having the ball scooping part 4a and the ball circulation path 4j. The road part 41 is formed from a separate part. Furthermore, in this embodiment, it has the annular | circular shaped elastic component 42 interposed coaxially between the upper surface 43j of each scooping component 43A, 43B, and the lower surface 41k of the circulation path component 41. FIG. The elastic component 42 of the present embodiment is made of synthetic rubber that can be elastically deformed in the axial direction. The elastic component 42 is not limited to a synthetic rubber, and may be made of a synthetic resin, a disc spring or a wave washer that can be elastically deformed in the axial direction as long as it is elastically deformable in the axial direction. It may be made of metal.

Each of the pair of scooping parts 43A and 43B and the circulation path part 41 is formed of a metal pipe material having an inner diameter that matches the diameter of the ball 3 circulating inside each part. The circulation path component 41 is formed by bending a metal pipe material into a U shape. The scooping parts 43A and 43B are formed of a cylindrical pipe material having a center axis CL as a trajectory drawn by the center of the ball 3 circulating in the scooping parts 43A and 43B. Then, the ball scooping portion 4 a formed at the lower portion is cut into a predetermined tongue shape having a scooping scooping angle along the lead angle of the ball screw 10.

Each scooping component 43A, 43B has a cylindrical shape and an upper surface 43j that allow rotation about the central axis CL when mounted on the tube mounting portion 25, respectively. Here, in the present embodiment, the upper surface 43j is a plane orthogonal to the central axis CL. In addition, the lower surface 41k of the circulation path component 41 facing the upper surface 43j is also a plane orthogonal to the central axis CL when mounted on the tube mounting portion 25.
The inner and outer diameters of the elastic component 42 are the same as the inner and outer diameters of the pipe material, and both the upper and lower surfaces of the elastic component 42 are a plane orthogonal to the central axis CL when the tube mounting portion 25 is mounted. Has been. As a result, each scooping component 43A, 43B can rotate about its central axis CL when mounted on the tube mounting portion 25.

Next, an assembly process of the ball screw 10, that is, a method for manufacturing the ball screw 10 will be described.
When assembling the ball screw 10, first, as shown in FIG. 4, the pair of scooping parts 43 </ b> A and 43 </ b> B are assembled in the counterbore holes 27 provided in the pair of tube mounting portions 25 of the installation surface 23. Each scooping component 43A, 43B is inserted at a position where the ball scooping portion 4a at its lower end faces the through hole 26, and the insertion position in the axial direction is regulated at the bottom surface of the counterbore hole 27.

Then, in the assembled state, a predetermined number of balls 3 are inserted into the rolling path 7 from the upper openings of the scooping parts 43A and 43B into the counterbore holes 27 of the tube mounting portions 25 (first step). . Next, the annular elastic component 42 is mounted on the upper surface 43j of each scooping component 43A, 43B in a mounting posture that is coaxial (elastic component mounting step). This elastic component mounting step may be performed before inserting the predetermined number of balls 3 in the first step.
After the first step, the ball 3 is packed in the U-shaped circulation path component 41, and the circulation path component 41 packed with the ball 3 is circulated with a pair of scooping components 43A and 43B and the ball 3. With the elastic part 42 interposed between the road parts 41, the upper part of the pair of scooping parts 43A and 43B is assembled to the tube mounting portion 25 of the nut 2 (second step).

After the second step, the ball 3 is circulated by rotating the nut 2 or the screw shaft 1 while lightly pressing the circulation path component 41 by hand. By circulating the ball 3, the ball 3 collides with the ball scooping portion 4a of each scooping component 43A, 43B many times.
At this time, each scooping component 43A, 43B has a top surface 43j that is a plane perpendicular to the central axis CL when mounted on the tube mounting portion 25, and both the upper and lower surfaces of the elastic component 42 and the circulation path. Since the lower surface 41k of the part 41 is also a similar plane, each scooping part 43A, 43B can freely move in the rotational direction around the axis as long as the circulation path part 41 is lightly pressed by hand. Can do.

Therefore, the scooping parts 43A and 43B in which the ball 3 is repeatedly collided with the ball scooping portion 4a are subjected to the scooping part 43 (one of the scooping parts 43A and 43B (the same applies hereinafter) by the collision force). As shown in the image)) rotating around the axis, the scooping component 43 rotates around the axis so that the most colliding force is in a position. In FIG. 9A, an arrow indicated by a symbol R indicates a centering action in which the scooping component 43 rotates around the central axis CL when the ball 3 collides with the ball scooping portion 4a of the scooping component 43. This shows the image that occurs.

Further, according to the present embodiment, when the ball 3 collides with the ball scooping portion 4a as shown by the broken line M in FIG. Since the scooping component 43 moves in the axial direction due to the elastic deformation of 42, the ball scooping portion 4 a moves as if it “shrinks” in the axial direction, thereby providing a buffering effect and performing the above-mentioned alignment function. Can assist effectively.
Thereby, it can prevent or suppress that the ball | bowl 3 collides with the unexpected location of the scooping components 43A and 43B by the processing error of each scooping components 43A and 43B, and a operability deteriorates. It can be improved (third step).

In the third step, the screw shaft 1 or the nut 2 is rotated for a while, and after the third step, circulation is performed using a tube presser 5 for fixing to the outer surface of the nut 2 as shown in FIG. The road part 41 is pressed toward the installation surface 23, and as shown in FIG. 1, the scooping parts 43A and 43B are fixed together with the circulation path part 41 with the bolt 6 (fourth step). As a result, the scooping parts 43 </ b> A and 43 </ b> B are also fixed to move in the rotational direction via the elastic parts 42.
Through the above assembly process, the ball circulation tube 4 is inserted in a desired posture into the pair of tube mounting portions 25 formed on the installation surface 23 with the ball scooping portions 4a of the scooping components 43A and 43B on both sides. The circulation path component 41 scoops up the ball 3 of the rolling path 7 from the ball scooping portion 4a on one end side so that the ball 3 circulates on the outer surface of the nut 2, and on the other end side through the ball circulation path 4j. It is mounted so as to return from the ball scooping portion 4a.

Here, in the case of a normal ball circulation tube in which the ball scooping portion 4a and the ball circulation path 4j are integrated, the amount of pressing the ball circulation tube toward the mounting surface 23 varies due to a processing error of the tube retainer 5. There is a case.
If the amount of press-in is insufficient, a gap T is generated between the integrated ball circulation tube 104 and the tube retainer 5 as shown in a comparative example in FIG. May not be fixed. If the amount of press-in is too large, the tube presser 5 may press the ball circulation tube 104 too much and cause deformation of the ball circulation tube 104 as shown in the comparative example in FIG. Show excessive image).

On the other hand, according to this embodiment, the elastic part 42 formed of a material that can be elastically deformed in the axial direction is interposed between the circulation path part 41 and the scooping parts 43A and 43B. As shown in the embodiment in FIG. 7C, the tightening error caused by the machining error in the axial direction of the scooping parts 43A and 43B and the circulation path part 41, the processing error of the tube presser 5, etc. , 43B and the circulation path part 41 are absorbed by the elastic part 42, and the scooping parts 43A, 43B and the circulation path part 41 can be securely fixed with an appropriate force.
Thereby, in the ball screw 10 of the present embodiment, when the ball 3 rolls along the rolling path 7 by the relative rotational movement of the nut 2 and the screw shaft 1, the ball 3 scoops one ball of the ball circulation tube 4. Circulation is smoothly repeated by scooping up from the rolling path 7 by the raising part 4a and entering the ball circulation tube 4 and entering the rolling path 7 again from the ball scooping part 4a on the opposite side through the ball circulation path 4j. It can be done.

Next, functions and effects of the ball screw 10 will be described.
As described above, according to this ball screw 10, since the ball circulation tube 4 has a split structure, the mounting postures of the scooping parts 43A and 43B can be individually adjusted. Therefore, even if a processing error has occurred in the ball scooping portion 4a between the pair of scooping parts 43A and 43B, the influence of the processing error can be prevented or reduced.
That is, according to this ball screw 10, the ball circulation tube 4 is formed of a pair of scooping parts 43A and 43B and a circulation path part 41 as separate parts. The relative posture between the parts 43A and 43B can be individually adjusted. For example, the mounting posture of each scooping component 43A, 43B is individually adjusted with only the pair of scooping components 43A, 43B attached to the tube mounting portion 25 of the nut 2 without mounting the circulation path component 41. it can.

Therefore, there is an absolute processing error in the tongue-shaped ball scooping portion 4a of each scooping component 43A, 43B, or relative to the ball scooping portion 4a between the pair of scooping components 43A, 43B. Even when a machining error occurs, the influence of the machining error can be reduced as compared with a ball circulation tube in which the ball scooping portion 4a and the ball circulation path 4j are integrally formed.
Further, according to the ball screw 10, since the pair of scooping parts 43A and 43B and the circulation path part 41 are composed of separate parts, the scooping part 43A is not mounted. , 43B can be stuffed in a state where only the tube mounting portion 25 of the nut 2 is attached. Further, since the ball stuffing operation can be performed with the scooping parts 43A and 43B attached to the nut 2, as shown in FIG. 4B, the movement of the ball 3 in the direction out of the circulation path is the ball scooping part 4a. Since the ball 3 enters only in the desired direction S of the rolling path 7, there is an effect of preventing the ball 3 from entering the rolling path 7 in the direction outside the circulation path.

Further, according to the ball screw 10, each scooping component 43A, 43B is formed of a cylindrical member having a center axis CL as a trajectory drawn by the center of the ball circulating in the scooping component 43A, 43B. Since it has a cylindrical shape and an upper surface 43j that allow rotation about the central axis CL when mounted on the mounting portion 25, the scooping parts 43A and 43B can freely move in the rotational direction around the axis when the nut is mounted. Can do.
Therefore, in the rolling rotation after rolling the ball into the rolling path 7, the parts that are picked up to the position where the magnitude of the force that collides with the ball 3 is the smallest due to the collision force between the ball scooping part 4 a and the ball 3. 43A and 43B itself can be rotated. Therefore, it is possible to automatically mount the scooping parts 43A and 43B so as to reduce the influence of the processing error automatically during the leveling operation.

Further, according to the ball screw 10, the annular elastic part 42 is formed of a material that can be elastically deformed in the axial direction, and the upper surface 43 j of the scooping parts 43 A and 43 B and the lower surface 41 k of the circulation path part 41. Since the elastic parts 42 absorb the machining errors in the axial direction of the scooping parts 43A and 43B and the circulation path part 41, the scooping parts 43A and 43B and the circulation path part 41 Can be fixed with a sufficient tightening force.
Further, according to the method for manufacturing the ball screw 10 described above, in the first step, the pair of scooping parts 43A and 43B described above are assembled to the tube mounting part 25 of the nut 2, so that the scooping part 43A is attached when the nut is mounted. , 43B can be freely moved in the direction of rotation around the axis. Therefore, there is an absolute processing error in the ball scooping part 4a of each scooping part 43A, 43B, or there is a relative processing error in the ball scooping part 4a between the pair of scooping parts 43A, 43B. Even if it occurs, the influence of the processing error can be reduced.

In this assembled state, the ball 3 is inserted into the rolling path 7 from the upper opening of the pair of scooping parts 43A and 43B, so the ball 3 is inserted into the rolling path 7 between the screw shaft 1 and the nut 2. At the time of insertion, the balls 3 can be incorporated so that the balls 3 do not enter in the direction in which the balls 3 should not be inserted by attaching the scooping parts 43A and 43B to the nut 2 in advance.
Moreover, according to the manufacturing method of the ball screw 10 described above, after the first step, the balls 3 are packed in the circulation path component 41 and the circulation path component 41 packed with the balls 3 is paired up. A second step of assembling the parts 43A and 43B from the upper part of the tube mounting portion 25 of the nut 2 and, after this second step, while turning the nut 2 or the screw shaft 1 while holding the circulation path component 41, And the third step of rotating the scooping parts 43A and 43B themselves around their axes by the force of the ball 3 colliding with the ball scooping part 4a of the scooping parts 43A and 43B. In the process, the ball 3 of the rolling path 7 is scooped up from the ball scooping portion 4a on one end side so that the ball 3 circulates on the outer surface of the nut 2, and the other end side through the ball circulation path 4j. It is possible to return from the ball scooping portion 4a.

In the third step, the ball 3 collides with the ball scooping part 4a of the scooping parts 43A and 43B by rotating the nut 2 or the screw shaft 1 and circulating the ball 3 while holding the circulation path part 41. Since the scooping-up component itself is rotated about its axis by the force of the scooping, the scooping-up component itself can be rotated about its axis at a position where the force with which the ball scooping portion 4a collides with the ball 3 is minimized. Accordingly, it is possible to prevent or suppress the operability from deteriorating due to the processing error of the scooping parts 43A and 43B and the ball 3 colliding with an unexpected part of the scooping parts 43A and 43B. Can be improved.

Further, in the second step, the balls 3 are packed in the circulation path component 41, and the circulation path component 41 packed with the balls 3 is replaced with a pair of scooping parts 43A and 43B and the circulation path packed with the balls 3. In a state where the elastic part 42 is interposed between the parts 41, the ball circulation tube 4 is attached to the tube mounting portion 25 of the nut 2 from the upper part of the pair of scooping parts 43A and 43B. 2 is used to hold the circulation path component 41 and the scooping parts 43A and 43B together with the circulation path component 41. According to this ball screw 10 manufacturing method, The elastic part 42 interposed between the parts 43A and 43B and the circulation path part 41 absorbs machining errors in the axial direction of the scooping parts 43A and 43B and the circulation path part 41. The scoop parts 43A, 43B and a circulation path component 41 can be fixed at the same time neither excessive nor insufficient clamping force.

As described above, according to the ball circulation tube 4 of the present embodiment, the ball screw 10 including the same, and the manufacturing method thereof, it is possible to reduce the influence of the processing error of the scooping portion. Note that the ball circulation tube for ball screw, the ball screw, and the manufacturing method of the ball screw according to the present invention are not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the present invention. .
For example, in the above-described embodiment, the ball circulation tube 4 has been described as an example in which the elastic part 42 is interposed between the scooping parts 43A and 43B and the circulation path part 41. It is good also as an aspect which does not interpose. However, in this case, as described with reference to FIG. 6, it becomes difficult to absorb the fluctuation range of the pressing amount of the tube presser 5. Therefore, in order to securely fix the scooping parts 43A and 43B and the circulation path part 41 with an appropriate force, the ball circulation in which the elastic parts 42 are interposed between the scooping parts 43A and 43B and the circulation path part 41. The tube 4 is preferable.

Further, for example, in the above-described embodiment, the facing surfaces of the scooping parts 43A and 43B, the circulation path part 41, and the elastic part 42 are all flat surfaces orthogonal to the central axis CL when mounted on the tube mounting part 25. However, the present invention is not limited to this. For example, a convex portion formed on one of the other surfaces is fitted to a concave portion formed on one of the opposite surfaces. One or a plurality of uneven shapes can be provided.
In the case where this uneven shape is provided, when the scooping parts 43A and 43B and the circulation path part 41 are mounted on the tube mounting part 25, the mounting postures around the central axis of the scooping parts 43A and 43B are individually set. Can be adjusted (hereinafter also referred to as “alignment”), one of the concave portions has a circumferential dimension that is more aligned than the circumferential dimension of the other convex portion. It may be formed slightly wider by a corresponding dimension. Moreover, the uneven | corrugated relationship of a mutual opposing surface may be reversed.

Hereinafter, a modified example in which such an uneven shape is provided will be described with reference to the drawings. In addition, since each modified example demonstrated below is the same structure as the said embodiment except the uneven | corrugated shape which mutually fits in the mutually opposing surface, description except a difference is abbreviate | omitted. In addition, in the following modified examples, except for the case where a pair of scooping parts 43A and 43B are shown together, the scooping parts 43 will be described without particularly distinguishing each other.

[First modification]
A first modification is shown in FIGS. 7 to 9 (note that FIG. 7 is common to the following second modification). In the first modification, as shown in FIG. 7, the scooping component 43 and the elastic component 42 are provided with concave and convex shapes ( reference numerals 43 t and 42 d) that are fitted to each other on each other, and combined with each other. Thus, this is an example in which assemblability is improved by preventing misalignment between the axes.
That is, in the first modification, the scooping component 43 is formed toward the elastic component 42 side at a position near the inner peripheral surface of the upper surface 43j that is a surface facing the elastic component 42, as shown in FIG. The convex portions 43t are provided at two opposing positions in the radial direction. Further, as shown in FIG. 9, the elastic component 42 is fitted with the two convex portions of the scooping component 43 at positions near the inner peripheral surface of the lower surface 42 s that is the surface facing the scooping component 43. Two recesses that can be formed are provided.
According to the configuration of the first modified example, the scooping component 43 and the elastic component 42 are scooped against the concave portion 42d formed on the mutually opposing surfaces at a position near the inner peripheral surface of the lower surface 42s of the elastic component 42. Since the convex portion 43t formed at a position near the inner peripheral surface of the upper surface 43j of the raised component 43 has a concave / convex shape to be fitted, the concave / convex shapes to be fitted to each other are combined in addition to the operational effects of the above embodiment. Thus, it is possible to improve the assembling property by preventing the displacement around the mutual axes.

[Second modification]
Next, a second modification is shown in FIGS. The second modified example is different from the first modified example in that an uneven shape ( reference numerals 43t and 42d) is formed at a position closer to the outer peripheral surface.
That is, in the second modification, the scooping component 43 is formed toward the elastic component 42 side at a position near the outer peripheral surface of the upper surface 43j that is a surface facing the elastic component 42, as shown in FIG. Two convex portions 43t are provided. Further, as shown in FIG. 11, the elastic component 42 can be fitted with the two convex portions 43 t of the scooping component 43 at a position near the outer peripheral surface of the lower surface 42 s that is a surface facing the scooping component 43. Two recesses 42d are formed at the two locations.
According to the configuration of the second modified example, as in the first modified example, the scooping component 43 and the elastic component 42 are formed on the mutually opposing surfaces at a position near the outer peripheral surface of the lower surface 42s of the elastic component 42. Since the convex portion 43t formed at a position near the outer peripheral surface of the upper surface 43j of the scooping part 43 is fitted to the concave portion 42d, the fitting portion is fitted to each other in addition to the function and effect of the above embodiment. By combining the concavo-convex shapes, the assemblability can be improved by preventing the displacement around the mutual axes.

[Third modification]
Next, a third modification is shown in FIGS.
As shown in FIG. 12, the third modification is provided with concave and convex shapes ( reference numerals 29 and 43d) that are fitted to each other on the facing surfaces of the scooping component 43 and the counterbore 27 of the tube mounting portion 25, and This is an example in which the concave portion 29 is slightly wider than the convex portion 43d by a dimension corresponding to the alignment amount.
That is, in the third modified example, the scooping component 43 has a position near the outer peripheral surface of the lower surface 43 s that is a surface facing the countersink hole 27, as shown in FIG. A convex portion 43d having a width W formed in the direction is provided on one side substantially opposite to the ball scooping portion 4a. Further, as shown in FIG. 14, the bottom surface of the counterbore 27, which is the surface facing the scooping component 43, can be fitted to the convex portion 43d of the scooping component 43 at a position near the outer peripheral surface of the bottom surface. One recess 29 having a groove width H is formed.

In the third modification, the concave portion 29 formed on the bottom surface of the counterbore hole 27 has a groove width H around the central axis, the central axis of the convex portion 43 d formed on the lower surface 43 s of the scooping component 43. The dimension corresponding to the alignment amount is slightly wider than the dimension of the surrounding width W (H> W).
As a specific configuration example of the main part, FIGS. 14C and 14D are enlarged views at the time of fitting. In this third modified example, as shown in FIG. 4C, the convex portion 43d and the concave portion 29 do not reach the bottom surface of the concave portion 29 in the axial direction when the convex portion 43d and the concave portion 29 are fitted. Set to Further, the convex portion 43d and the concave portion 29 are gap fittings having a gap having a size corresponding to the alignment amount between the outer surface of the convex portion 43d and the inner side surface of the concave portion 29 in the circumferential direction. Yes.

In addition, as shown to the same figure (d), it is good also considering the lower end surface of the convex part 43d as the downward direction, and making a center part into a curved surface convex. In this case, at the time of fitting, the convex portion 43d and the concave portion 29 are set so that the convex curved surface at the lower end of the convex portion 43d is in sliding contact with the bottom surface of the concave portion 29 in the axial direction, and in the circumferential direction, the above adjustment is performed. Fit the gap according to the amount of heart.
According to the configuration of the third modified example, as shown in FIGS. 14C and 14D, the dimension around the central axis of the concave portion 29 is more aligned than the dimension around the central axis of the convex portion 43d. Since the corresponding dimension is slightly wider (H> W), the scooping component 43 can be provided with alignment as with the operational effects of the above embodiment.
Furthermore, according to the configuration of the third modified example, the rotatable range around the central axis of each scooping component 43A, 43B can be regulated by the concavo-convex shape that fits together. Therefore, positioning can be facilitated while aligning each scooping part 43A, 43B.

[Fourth modification]
Next, a fourth modification is shown in FIGS. 15 to 18 (note that FIGS. 15 and 16 are common to the following fifth modification). In the fourth modified example, the scooping part 43 and the circulation path part 41 have a concave-convex shape ( reference numerals 43t, 41d) in which either one of the concave parts is fitted to either one of the convex parts. In addition, the concave portion formed on one of the surfaces has a dimension around the central axis CL that is more dependent on the amount of alignment than the dimension around the central axis CL of the convex portion formed on either one of the surfaces. This is an example in which a groove 42h through which a convex portion can pass is provided in the elastic part 42 that is formed slightly wider in size and is interposed.

That is, in the fourth modified example, the circulation path component 41 has a groove width S penetrating along the radial direction at the center of the two lower surfaces 41k that are opposed to the scooping component 43, as shown in FIG. Each of the concave portions 41d is provided in two places (four places in total). Further, as shown in FIG. 17, the scooping component 43 is formed at a position near the inner peripheral surface of the upper surface 43 j that is a surface facing the circulation channel component 41, toward the lower surface side of the circulation channel component 41. Two convex portions 43t are provided, and each convex portion 43t is formed to be able to fit into two concave portions 41d of the circulation path component 41, respectively.
Further, as shown in FIG. 18, the elastic component 42 is provided with two grooves 42 h on the inner peripheral surface through which two convex portions formed on the upper surface 43 j of the scooping component 43 can pass. The groove width M of the groove 42h of the elastic part 42 is a clearance fit slightly larger than the width W of the convex part 43t of the scooping part 43 shown in FIG. 17 (M> W). Thereby, in the mutual fitting state, when a strong assembling force (axial compressive force F1) does not act (during alignment), a slight gap is generated between the opposing surfaces. Further, as shown in FIG. 19, when a compressive force F1 is applied to the elastic part 42 in the axial direction during assembly, the left and right sides of the convex portion 43t are brought into close contact with each other due to elastic deformation of the elastic part 42. Is set to generate a clamping force F2. In the figure, an image of elastic deformation in which the elastic part 42 is shortened in the axial direction is indicated by a broken line and a symbol d.

In the fourth modification, as in the above embodiment, the recess 41d formed on the lower surface 41k of the circulation path component 41 has a dimension around the central axis CL (in this example, the groove width S) of the scooping component 43. The dimension corresponding to the alignment amount is slightly wider than the dimension around the central axis CL of the convex part 43t formed on the upper surface 43j (in this example, the width W of the convex part 43t) (S> W). . In addition, as a specific structure (relative position) of the main part of the uneven | corrugated | grooved part mutually fitted, in the 3rd modification mentioned above, it is the same as that of the fitting example shown in FIG.14 (c) and (d). It can be configured.
According to the configuration of the fourth modification, the recess 41 d formed on the lower surface 41 k of the circulation path component 41 has a dimension around the center axis CL that is the center axis of the projection 43 t formed on the upper surface 43 j of the scooping component 43. Since the dimension corresponding to the alignment amount is slightly wider than the dimension around CL (S> W), the scooping component 43 can be aligned as in the above embodiment.

Furthermore, according to the configuration of the fourth modified example, the rotatable range around the central axis CL of each scooping component 43A, 43B can be restricted by the concave and convex shapes of the concave portion 41d and the convex portion 43t that are fitted to each other. Therefore, it is possible to easily position the scooping parts 43A and 43B while aligning them.
Further, the groove 42h of the elastic component 42 and the convex portion 43t of the scooping component 43 have a clearance fit between the opposing surfaces during alignment, and a close fit between the opposing surfaces when assembled. Each component can be securely fixed by fixing in the fourth step while maintaining the alignment in the third step.

[Fifth Modification]
Next, a fifth modification is shown in FIGS. The fifth modified example is different from the fourth modified example in that the convex portion 43t of the scooping component 43 and the groove 42h of the elastic component 42 are formed at positions close to the outer peripheral surface.
That is, in the fifth modification, as shown in FIG. 16, the circulation path component 41 has a diameter at the center of the two lower surfaces 41 k that are opposed to the scooping component 43, as in the fourth modification. Each of the recesses 41d penetrating along the direction is provided at two places (four places in total). As shown in FIG. 20, the scooping component 43 has a convex formed on the lower surface side of the circulation path component 41 at a position near the outer peripheral surface of the upper surface 43 j that is a surface facing the circulation path component 41. Two portions 43t are provided, and each convex portion 43t is formed so as to be fitted to two concave portions 41d of the circulation path component 41, respectively. In addition, as a specific structure (relative position) of the main part of the uneven | corrugated | grooved part mutually fitted, in the 3rd modification mentioned above, it is the same as that of the fitting example shown in FIG.14 (c) and (d). It can be configured.

Also in the fifth modified example, the recess 41d formed on the lower surface 41k of the circulation path component 41 is formed on the upper surface 43j of the scooping component 43 in the same dimension as the fourth modified example. The protrusion 43t is formed slightly wider than the dimension around the center axis CL by a dimension corresponding to the alignment amount.
Further, as shown in FIG. 21, the elastic part 42 is provided with two grooves 42 h on the outer peripheral surface through which the two convex portions 43 t formed on the upper surface 43 j of the scooping part 43 can pass. The groove 42h of the elastic component 42 and the convex portion 43t of the scooping component 43 are clearances where a gap is generated between the opposing surfaces during alignment, and the opposing surfaces are in close contact during assembly, as in the fourth modification. It has become.

According to the configuration of the fifth modification, as in the fourth modification, the recess 41d formed on the lower surface 41k of the circulation path component 41 is formed on the upper surface 43j of the scooping component 43 with a dimension around the central axis CL. Since the projected portion 43t is slightly wider than the dimension around the center axis CL of the convex portion 43t, the positioning of the scooping parts 43A and 43B is adjusted while maintaining the alignment as in the fourth modification. Can be made easier.
Further, the groove 42h of the elastic component 42 and the convex portion 43t of the scooping component 43 have a gap between the opposing surfaces during alignment, and the opposing surfaces are in close contact during assembly, as in the fourth modification. Since it is a clearance fit, each part can be securely fixed by fixing in the fourth step while maintaining alignment in the third step.

DESCRIPTION OF SYMBOLS 1 Screw shaft 2 Nut 3 Ball 4 Ball circulation tube 4a Ball scooping part 4j Ball circulation path 5 Tube retainer 6 Bolt 7 Rolling path 10 Ball screw 11 Screw shaft thread groove 21 Nut thread groove 22 Flange 23 Mounting surface 24 Installation Screw hole 25 Tube mounting part 41 Circulating path part 42 Elastic part 43 (43A, 43B) Scooping part

Claims (10)

1. A screw shaft having a spiral thread groove on the outer peripheral surface, a nut having a spiral thread groove on the inner peripheral surface, and a plurality of balls arranged in a rolling path formed by these thread grooves. Used in a ball screw, mounted on the tube mounting portion of the nut, scoops the ball of the rolling path from the ball scooping portion on one end side so that the ball circulates on the outer surface of the nut, and the ball circulation path A ball circulation tube to be returned from the ball scooping portion on the other end side through
   A ball circulation tube for a ball screw, wherein a pair of scooping parts each having the ball scooping part and a circulation path part having the ball circulation path are formed of separate parts.
2. The scooping part is formed of a cylindrical member having a center axis as a track drawn by the center of the ball circulating in the scooping part, and rotates around the central axis when mounted on the tube mounting part. The ball circulation tube for a ball screw according to claim 1, which has an allowable cylindrical shape and upper surface.
3. The ball circulation tube for a ball screw according to claim 2, further comprising an annular elastic part that is elastically deformable in an axial direction and is coaxially interposed between an upper surface of the scooping part and a lower surface of the circulation path part.
4. The scooping component and the elastic component have a concavo-convex shape in which a convex portion formed on one of the other surfaces is fitted to a concave portion formed on one of the opposing surfaces. Item 4. A ball circulation tube for ball screw according to Item 3.
5. 5. The concave portion formed on one of the surfaces has a dimension around the central axis wider than a dimension around the central axis of a convex portion formed on the other surface. Ball circulation tube for ball screw as described in 1.
6. The scooping component and the tube mounting portion of the nut have a concave-convex shape in which the concave portion formed on one of the other surfaces is fitted to the convex portion formed on one of the opposing surfaces. The convex portion formed on one of the surfaces has a dimension around the central axis wider than the dimension around the central axis of the concave portion formed on the other surface. The ball circulation tube for a ball screw according to any one of claims 3 to 5.
7. A screw shaft having a spiral thread groove on the outer peripheral surface, a nut having a spiral thread groove on the inner peripheral surface, and a plurality of balls disposed in a rolling path formed by these thread grooves, Mounted on the tube mounting portion of the nut, the ball of the rolling path is scooped up from the ball scooping portion on one end side so that the ball circulates on the outer surface of the nut, and on the other end side through the ball circulation path. A ball screw including a ball circulation tube returning from a ball scooping portion,
   A ball screw comprising the ball circulation tube for a ball screw according to any one of claims 1 to 6, as the ball circulation tube.
8. A method for producing a ball screw having the ball circulation tube for ball screw according to any one of claims 1 to 6,
   Including a first step of assembling the pair of scooping parts to the tube mounting portion and, in the assembled state, inserting the ball into the rolling path from an upper opening of the pair of scooping parts. To manufacture a ball screw.
9. After the first step, the second step of packing the ball in the circulation path component and assembling the circulation path component packed with the ball from the upper part of the pair of scooping components to the tube mounting portion; ,
   After the second step, the ball is circulated by rotating the nut or the screw shaft while pressing the circulation path component, so that the ball collides with the ball scooping portion of the scooping component. The ball screw manufacturing method according to claim 8, further comprising a third step of rotating the scooping component itself about its axis.
10. A method for producing a ball screw having a ball circulation tube for a ball screw according to any one of claims 3 to 6,
    Assembling the pair of scooping parts to the tube mounting portion, and in the assembled state, a first step of inserting the ball into the rolling path from the upper openings of the pair of scooping parts;
    After the first step, the ball is packed in the circulation path part, and the circulation path part packed with the ball is placed between the pair of scooping parts and the circulation path part packed with the ball. A second step of assembling the tube mounting portion of the nut from the upper part of the pair of scooping parts in a state of interposing the parts;
    After the second step, the ball is circulated by rotating the nut or the screw shaft while pressing the circulation path component, so that the ball collides with the ball scooping portion of the scooping component. A third step of rotating the scooping component itself around its axis;
    After the third step, a fourth step of pressing the circuit part using a tube presser for fixing the ball circulation tube to the outer surface of the nut and fixing the scooping part together with the circuit part. A method of manufacturing a ball screw.

Images