JP2019184014A - Intermediate shaft - Google Patents

Abstract

To provide an intermediate shaft in which joining between a sleeve and a connecting member can be stably maintained for a long period of time.SOLUTION: An intermediate shaft 100 comprises: an outer shaft 140 (sleeve) having, at an internal circumferential surface, a ball groove 142 formed along an X-axis direction (axial direction); a tube 160 (connecting member) joined to one end part of the outer shaft 140; and a caulked part 200 which is formed by caulking at least either of one end part of the outer shaft 140 and of the tube 160. The caulked part 200 is arranged in a position circumferentially different from the ball groove 142.SELECTED DRAWING: Figure 10

Description

  The present invention relates to an intermediate shaft.

  In general, in an automobile, a steering shaft connected to a steering wheel and a pinion shaft as a steering gear shaft are connected via an intermediate shaft. The sleeve and shaft of the intermediate shaft can be expanded and contracted by adopting, for example, an expansion / contraction shaft (for example, see Patent Document 1) provided with a ball groove and a ball.

  In addition, a yoke forming a part of a universal joint connected to the pinion shaft is directly joined to the other end of the sleeve, or a tube interposed between the yoke and the yoke is directly joined.

JP 2010-53943 A

  In the intermediate shaft, the connection between the connecting member such as a yoke or a tube and the sleeve may be deteriorated. The deterioration of the joining causes a positional deviation between the connecting member and the sleeve.

  An object of this invention is to provide the intermediate shaft which can maintain the joining of a sleeve and a connection member stably for a long term.

  In order to solve the above-described problem, an intermediate shaft according to one aspect of the present invention includes a sleeve having a ball groove along the axial direction on an inner peripheral surface, a connecting member joined to one end of the sleeve, A crimping portion formed by crimping at least one of the one end portion of the sleeve and the connecting member is provided, and the crimping portion is arranged at a different position in the circumferential direction with respect to the ball groove.

  According to the intermediate shaft according to the present invention, the joining between the sleeve and the connecting member can be stably maintained over a long period of time.

It is a schematic diagram which shows an example of the usage condition of the intermediate shaft which concerns on embodiment. It is a perspective view which shows schematic structure of the intermediate shaft which concerns on embodiment. It is a perspective view which decomposes | disassembles and shows the outer shaft and tube with which the intermediate shaft which concerns on embodiment is equipped. It is a top view which shows the shape of the other end part of the tube which concerns on embodiment. It is sectional drawing of the one end part of the outer shaft which concerns on embodiment. It is a top view which shows the shape of the one end part of the outer shaft which concerns on embodiment. It is sectional drawing which shows the state immediately after the assembly | attachment of the other end part of the tube which concerns on embodiment, and the one end part of an outer shaft. It is sectional drawing which looked at the cut surface containing the VIII-VIII cutting line in FIG. It is sectional drawing which looked at the cut surface containing the IX-IX cutting line in FIG. FIG. 10 is a cross-sectional view showing a state after crimping between the other end of the tube and one end of the outer shaft according to the embodiment.

  Hereinafter, embodiments will be specifically described with reference to the drawings. It should be noted that each of the embodiments described below shows a comprehensive or specific example. Numerical values, shapes, materials, constituent elements, arrangement positions and connection forms of constituent elements, and the like shown in the following embodiments are merely examples, and are not intended to limit the present invention. In addition, among the constituent elements in the following embodiments, constituent elements that are not described in the independent claims indicating the highest concept are described as optional constituent elements.

  In addition, the drawings are schematic diagrams in which emphasis, omission, and ratio adjustment are appropriately performed to show the present invention, and may differ from actual shapes, positional relationships, and ratios.

  Drawing 1 is a mimetic diagram showing an example of a use form of intermediate shaft 100 concerning an embodiment. As shown in FIG. 1, the intermediate shaft 100 is provided in a steering apparatus 10 for an automobile. Specifically, the steering device 10 includes a steering shaft 12 having a steering wheel 11 connected to one end thereof, and a rack and pinion mechanism including a pinion shaft 13 and a rack shaft 14. And an intermediate shaft 100 that is interposed between the steering shaft 12 and the pinion shaft 13 and transmits steering torque.

  One end of the intermediate shaft 100 is connected to the steering shaft 12 via the first universal joint 17. The other end of the intermediate shaft 100 is connected to the pinion shaft 13 via the second universal joint 18.

  When the steering wheel 11 is operated to rotate the steering shaft 12, the rotation is transmitted to the pinion shaft 13 and the rack shaft 14 through the intermediate shaft 100. Thereby, the steering mechanism 16 turns the steered wheels 15.

  Next, the intermediate shaft 100 according to the present embodiment will be described in detail. FIG. 2 is a perspective view showing a schematic configuration of the intermediate shaft 100 according to the embodiment. FIG. 3 is an exploded perspective view showing the outer shaft 140 and the tube 160 provided in the intermediate shaft 100 according to the embodiment. In FIG. 2 and subsequent figures, an orthogonal coordinate system in which the X-axis direction is the axial direction of the intermediate shaft 100 is used. That is, the Y-axis direction and the Z-axis direction that are orthogonal to each other are also orthogonal to the X-axis direction. In the following description, the end on the X axis direction minus side is referred to as one end, and the end on the X axis direction plus side is referred to as the other end.

  As shown in FIG. 2, the intermediate shaft 100 includes a telescopic intermediate shaft 110, a first universal joint 17 provided at the other end of the intermediate shaft 110, and a second provided at one end of the intermediate shaft 110. A universal joint 18 is provided. The intermediate shaft 110 includes an outer shaft 140, an inner shaft 150, and a tube 160.

  As shown in FIGS. 2 and 3, the outer shaft 140 is an example of a sleeve that is disposed between the inner shaft 150 and the tube 160 and connects the inner shaft 150 and the tube 160.

  The outer shaft 140 is a cylindrical shaft body and has a through hole 141. An inner shaft 150 is inserted into the other end portion of the outer shaft 140 from the X axis direction plus side. A pair of ball grooves 142 extending in the X-axis direction are formed on the inner peripheral surface of the outer shaft 140 (see FIG. 6). The inner peripheral surface of the ball groove 142 is a concave curved surface when viewed in the X-axis direction. The pair of ball grooves 142 oppose each other in the Z-axis direction.

  The inner shaft 150 is a shaft body, and the first universal joint 17 is provided at the other end. The first universal joint 17 includes a first yoke 171 coupled to the inner shaft 150, a second yoke 172 coupled to the steering shaft 12, and a cross shaft 173 that connects the first yoke 171 and the second yoke 172. including. Each shaft portion of the cross shaft 173 is rotatably supported by the respective arms of the first yoke 171 and the second yoke 172 via a bearing (not shown).

  A pair of ball grooves 151 extending in the X-axis direction are formed on the outer peripheral surface of the inner shaft 150 (see FIG. 6). The inner peripheral surface of the ball groove 151 is a concave curved surface when viewed in the X-axis direction. The pair of ball grooves 151 are opposed to each other in the Z-axis direction. That is, in a state where the inner shaft 150 is inserted into the outer shaft 140 and assembled, the ball grooves 142 and 151 face each other in the Z-axis direction. A space formed by the ball grooves 142 and 151 is substantially circular when viewed in the X-axis direction. In this space, a plurality of balls B arranged in the X-axis direction are arranged. Since the plurality of balls B slide in the ball grooves 142 and 151, the inner shaft 150 and the outer shaft 140 can smoothly expand and contract in the X-axis direction. The outer shaft 140 and the inner shaft 150 are provided with a structure that restricts the ball B from coming off. Specifically, a lid 147 is attached to the other end of the outer shaft 140. The lid 147 is formed with a through hole 148 for allowing the inner shaft 150 to slide and a wall portion 149 for restricting the ball B from coming off. A stopper member (not shown) that restricts the ball B from being removed is provided at one end of the inner shaft 150.

  The tube 160 is an example of a connecting member joined to one end of the outer shaft 140. The tube 160 is a cylindrical shaft body and has a through hole 162. A second universal joint 18 is provided at one end of the tube 160. The second universal joint 18 includes a first yoke 181 coupled to the tube 160, a second yoke 182 coupled to the pinion shaft 13, and a cross shaft 183 connecting the first yoke 181 and the second yoke 182. Including. Each shaft portion of the cross shaft 183 is rotatably supported by the respective arms of the first yoke 181 and the second yoke 182 via a bearing (not shown).

  The other end of the tube 160 is joined to one end of the outer shaft 140. Hereinafter, a joint structure between the tube 160 and the outer shaft 140 will be described. Specifically, the convex portion 161 provided at the other end portion of the tube 160 and the fitting portion 144 provided at one end portion of the outer shaft 140 are fitted and welded, so that the tube 160 and the outer shaft are welded. 140 is joined.

  First, the other end portion of the tube 160 will be described in detail. FIG. 4 is a plan view showing the shape of the other end of the tube 160 according to the embodiment. As shown in FIGS. 3 and 4, the other end portion of the tube 160 includes a pedestal portion 163 and a convex portion 161.

  The pedestal portion 163 is an annular portion having an outer diameter smaller than that of the outer peripheral surface of the tube 160, and supports the convex portion 161 at the tip surface thereof. When viewed in the X-axis direction, the circle formed by the outer peripheral surface of the tube 160 and the circle formed by the outer peripheral surface of the pedestal 163 are concentric circles. For this reason, an equal stepped portion 164 is formed over the entire circumference of the outer peripheral surface of the tube 160 and the outer peripheral surface of the pedestal portion 163.

  The convex portion 161 is formed long in the Y-axis direction when viewed in the X-axis direction. Specifically, the convex portion 161 is formed in an oval shape that is long in the Y-axis direction. The pair of long side portions 161 a in the convex portion 161 are arranged in the Z-axis direction with the through hole 162 interposed therebetween. The pair of short side portions 161b in the convex portion 161 are arranged in the Y-axis direction with the through hole 162 interposed therebetween. A concave portion 165 is formed on the outer peripheral surface of each of the pair of short side portions 161 b in the convex portion 161. The pair of recesses 165 are arranged in the X-axis direction with the through-hole 162 interposed therebetween. That is, the pair of recesses 165 are equally arranged in the circumferential direction. Moreover, the convex part 161 is settled in the base part 163 in the X-axis direction view.

  Next, one end portion of the outer shaft 140 will be described in detail. FIG. 5 is a cross-sectional view of one end portion of the outer shaft 140 according to the embodiment. FIG. 6 is a plan view showing the shape of one end of the outer shaft 140 according to the embodiment. 5 is a cross-sectional view of the cut surface including the VV cut line in FIG. In FIG. 6, the outer shape of the inner shaft 150 is indicated by a broken line, and the outer shape of the ball B is indicated by a two-dot chain line.

  As shown in FIGS. 5 and 6, a guide portion 143 and a fitting portion 144 are provided at one end portion of the outer shaft 140. The guide part 143 is a part that guides the base part 163 of the tube 160 to a predetermined position during assembly. Specifically, the guide portion 143 is formed in an annular shape, and guides by sliding the pedestal portion 163 on the inner peripheral surface thereof. Since the stepped portion 164 of the tube 160 comes into contact with the distal end surface of the guide portion 143, further entry of the convex portion 161 is restricted.

  The fitting portion 144 is a portion where the convex portion 161 of the tube 160 is fitted. The fitting portion 144 is a portion disposed on the plus side in the X-axis direction with respect to the guide portion 143. The fitting portion 144 is provided continuously to the other end portion of the tube 160, but the portion to which the convex portion 161 is fitted is only a part on the distal end side.

  The fitting portion 144 is formed in an annular shape, and its inner peripheral surface is formed in a substantially oval shape that is long in the Y-axis direction. The pair of long side portions 144a in the fitting portion 144 are arranged in the Z-axis direction with the through hole 141 interposed therebetween. The pair of short side portions 144b in the fitting portion 144 are arranged in the Y-axis direction with the through hole 141 interposed therebetween. The short side portion 144b has the same thickness as the guide portion 143. On the other hand, the long side portion 144 a is formed thicker than the guide portion 143. A ball groove 142 is formed for each of the pair of long side portions 144a. Each of the pair of long side portions 144 a is formed with a pair of flat portions 146 that are arranged so as to sandwich the ball groove 142 in the circumferential direction and abut against the convex portion 161.

  Next, a method for assembling the tube 160 and the outer shaft 140 will be described. Here, a case where the operator assembles the tube 160 and the outer shaft 140 is illustrated, but the tube 160 and the outer shaft 140 may be automatically assembled by an assembling apparatus. Even in that case, the tube 160 and the outer shaft 140 are assembled in the same procedure.

  First, the operator assembles the other end of the tube 160 to one end of the outer shaft 140. Specifically, the operator inserts the convex portion 161 and the pedestal portion 163 of the tube 160 into the through hole 141 from one end portion side of the outer shaft 140. As a result, the base portion 163 slides on the inner peripheral surface of the guide portion 143 and the convex portion 161 is fitted to the fitting portion 144 until the distal end surface of the guide portion 143 contacts the stepped portion 164 of the tube 160. To do.

  FIG. 7 is a cross-sectional view showing a state immediately after assembly of the other end of the tube 160 and one end of the outer shaft 140 according to the embodiment. 8 is a cross-sectional view of a cut surface including a VIII-VIII cut line in FIG. 9 is a cross-sectional view of a cut surface including a IX-IX cut line in FIG. FIG. 7 is a cross-sectional view of the cut surface including the VII-VII cut line of FIGS. 8 and 9, and shows a fitting state between the convex portion 161 of the tube 160 and the fitting portion 144 of the outer shaft 140. ing.

  As shown in FIGS. 7 to 9, the pair of long side portions 161 a of the convex portion 161 is in contact with the pair of long side portions 144 a of the fitting portion 144, and the pair of short side portions of the convex portion 161. 161b is in contact with the pair of short side portions 144b of the fitting portion 144, respectively. Specifically, the pair of long side portions 144 a of the convex portion 161 are in surface contact with the flat portion 146 of the fitting portion 144. For this reason, for example, even if the tube 160 rotates, the outer shaft 140 also rotates without idling.

  Immediately after the fitting, since the short side portion 161b of the convex portion 161 has the concave portion 165, a gap is formed between the short side portion 161b of the convex portion 161 and the short side portion 144b of the fitting portion 144. Has been. The pair of recesses 165 are disposed at different positions in the circumferential direction with respect to the pair of ball grooves 142 of the outer shaft 140. Specifically, the arrangement direction of the pair of convex portions 161 (Y-axis direction in the present embodiment) is orthogonal to the direction orthogonal to the arrangement direction of the pair of ball grooves 142 (Z-axis direction in the present embodiment). It has become.

  Next, the operator joins the outer shaft 140 to the tube 160 by crimping one end portion of the outer shaft 140. FIG. 10 is a cross-sectional view showing a state after crimping between the other end of the tube 160 and one end of the outer shaft 140 according to the embodiment. FIG. 10 corresponds to FIG.

  Specifically, the operator forms the crimping portion 200 by crimping a portion of the outer shaft 140 that faces the recess 165. In the present embodiment, since the caulking portion 200 is provided for each of the pair of recesses 165, the number of the caulking portions 200 is two. For this reason, the two crimping parts 200 are arranged in the Y-axis direction. That is, the two crimping parts 200 are equally arranged in the circumferential direction. Further, the caulking portion 200 is plastically deformed by caulking and fits into the recess 165, and has a shape that is recessed from other portions after caulking. Since the caulking portion 200 is fitted in the recess 165 as described above, the outer shaft 140 and the tube 160 can be firmly joined.

  In the caulking process, a plurality of caulking portions 200 may be formed simultaneously using a jig or the like, or the caulking portions 200 may be formed one by one while rotating the outer shaft 140 and the tube 160.

  Next, the operator completes the assembly of the tube 160 and the outer shaft 140 by welding one end of the outer shaft 140 and the other end of the tube 160.

  As described above, the intermediate shaft 100 according to the present embodiment includes the outer shaft 140 (sleeve) having the ball groove 142 along the X-axis direction (axial direction) on the inner peripheral surface, and one end portion of the outer shaft 140. And a crimping portion 200 formed by crimping at least one of one end of the outer shaft 140 and the tube 160, and the crimping portion 200 includes the ball groove 142. Are arranged at different positions in the circumferential direction.

  According to this, since the crimping part 200 formed by crimping at least one of the one end part of the outer shaft 140 and the tube 160 is provided, for example, welding is broken and the joining by welding is released. In addition, the joining by the caulking portion 200 can be maintained. That is, since the double joint structure is adopted, the joint between the outer shaft 140 and the tube 160 can be stably maintained for a long time.

  Further, since the caulking portion 200 is disposed at a different position in the circumferential direction with respect to the ball groove 142, deformation of the ball groove 142 of the outer shaft 140 due to caulking can be suppressed. Therefore, expansion / contraction between the inner shaft 150 and the outer shaft 140 can be stabilized.

  In addition, since the tube 160 is provided between the first yoke 181 and the outer shaft 140, the intermediate shaft 110 can be lengthened by the tube 160. If the tubes 160 having different lengths are selected and used, the intermediate shaft 110 can be set to an arbitrary length.

  Further, a convex portion 161 protruding in the X-axis direction is provided at one end portion of the outer shaft 140, and a fitting portion 144 into which the convex portion 161 is fitted is provided in the tube 160, and the convex portion 161 and The fitting part 144 is non-circular when viewed in the X-axis direction.

  According to this, since the convex portion 161 and the fitting portion 144 are non-circular when viewed in the X-axis direction, even if both the joining by welding and the joining by the crimping portion 200 are released, the convex portion 161 and the fitting portion 144 are fitted. One of the joint portions 144 does not idle with respect to the other. Thereby, even in the case of an emergency, the outer shaft 140 and the tube 160 can be rotated simultaneously.

  Further, the fitting portion 144 is provided at one end portion of the outer shaft 140, the convex portion 161 is provided in the tube 160, and the convex portion 161 and the fitting portion 144 are formed long in the X-axis direction view. The ball groove 142 is provided in each of the pair of long side portions 144a in the fitting portion 144, and the crimping portion 200 is provided in each of the pair of short side portions 144b in the fitting portion 144. Yes.

  According to this, since the crimping part 200 is provided in each of a pair of short side part 144b in the fitting part 144, the two crimping parts 200 can be opposingly arranged. Therefore, since the two crimping parts 200 can be formed by compressing the outer shaft 140 so as to sandwich the outer shaft 140, the fastening force can be increased.

  Moreover, the long side part 144a in the fitting part 144 is a thicker part than the short side part 144b. Since the ball groove 142 is provided for the long side portion 144a, the ball groove 142 can be easily formed. Further, deformation of the ball groove 142 due to caulking can be further suppressed.

  In addition, the long side portion 144 a of the fitting portion 144 is formed with a pair of flat portions 146 that are disposed so as to sandwich the ball groove 142 and abut against the convex portion 161.

  According to this, since the pair of flat portions 146 of the fitting portion 144 are in contact with and in surface contact with the convex portion 161, one rotation of the outer shaft 140 and the tube 160 is smoothly transmitted to the other. can do.

  Further, one end portion of the outer shaft 140 and the tube 160 are welded.

  According to this, since the one end part of the outer shaft 140 and the tube 160 are welded, the outer shaft 140 and the tube 160 can be firmly joined.

  In addition, a plurality of crimping portions 200 are provided and are equally arranged in the circumferential direction.

  According to this, since the several crimping part 200 is arrange | positioned equally at the circumferential direction, it can suppress that each axial center of the outer shaft 140 and the tube 160 shifts | deviates by crimping.

  As mentioned above, although the intermediate shaft which concerns on this invention was demonstrated based on the said embodiment, this invention is not limited to said embodiment.

  For example, in the above-described embodiment, the tube 160 is illustrated as an example of the connecting member joined to one end portion of the outer shaft 140. However, the connecting member is not limited to the tube 160 as long as it is a member joined to one end of the outer shaft 140. Other examples of the connecting member include a yoke that constitutes a universal joint.

  In the above embodiment, the steering shaft 12 is connected to the first universal joint 17 on the other end side of the intermediate shaft 100, and the pinion shaft 13 is connected to the second universal joint 18 on the one end side. Was illustrated. However, the pinion shaft 13 may be connected to the first universal joint 17 of the intermediate shaft 100 and the steering shaft 12 may be connected to the second universal joint 18.

  In the said embodiment, the case where the convex part 161 and the fitting part 144 were elongate was illustrated. However, the convex part 161 and the fitting part 144 should just be non-circular. Since the convex portion 161 and the fitting portion 144 are non-circular, it is possible to prevent one of the convex portion 161 and the fitting portion 144 from spinning around the other. Examples of other shapes of the convex portion 161 and the fitting portion 144 include a polygonal shape and a substantially circular shape with a part cut away. Moreover, as long as idle rotation can be controlled, the convex part 161 and the fitting part 144 may have different shapes.

  Moreover, in the said embodiment, the intermediate shaft 100 by which joining by welding and joining by the crimping part 200 was employ | adopted was illustrated. However, it is also possible to employ a joining method other than welding. Examples of joining methods other than welding include press-fitting and adhesion.

  In the said embodiment, the case where the two crimping parts 200 were provided was illustrated. However, it is sufficient that there is one or more crimping portions. In addition, in the case where a plurality of crimping portions 200 are provided, it is desirable that they are arranged evenly in the circumferential direction, but they may be arranged unevenly in the circumferential direction. In this case, if the resultant force of the fastening force with respect to each crimping portion 200 when the plurality of crimping portions 200 are formed is aligned with the axis of the outer shaft 140, each of the outer shaft 140 and the tube 160 is It is possible to prevent the axial center from being displaced due to caulking.

  Moreover, in the said embodiment, the convex part 161 was provided in the one end part of the tube 160, and the case where the fitting part 144 was provided in the outer shaft 140 was illustrated. However, the convex part may be provided in the one end part of the outer shaft, and the fitting part may be provided in the tube. In this case, since the tube is disposed outside the outer shaft, a crimped portion is formed with respect to the tube.

  In addition, the embodiment can be realized by arbitrarily combining the components and functions in the embodiments and modifications without departing from the spirit of the present invention, and forms obtained by subjecting the embodiments to various modifications conceived by those skilled in the art. This form is also included in the present invention.

  The present invention is applicable to an intermediate shaft having a ball groove.

  DESCRIPTION OF SYMBOLS 10 Steering device, 11 Steering wheel, 12 Steering shaft, 13 Pinion shaft, 14 Rack shaft, 15 Steering wheel, 16 Steering mechanism, 17 First universal joint, 18 Second universal joint, 100 Intermediate shaft, 110 Intermediate shaft, 140 Outer shaft (sleeve), 141, 148, 162 Through hole, 142, 151 Ball groove, 143 Guide part, 144 Fitting part, 144a, 161a Long side part, 144b, 161b Short side part, 146 Flat part, 147 Lid Body, 149 Wall, 150 Inner shaft, 160 Tube (connecting member), 161 Convex, 163 Base, 164 Step, 165 Concave, 171, 181 First yoke, 172, 182 Second yoke, 173, 183 Cross Shaft, 200 crimping part, B ball

Claims (6)

A sleeve having a ball groove on the inner peripheral surface along the axial direction;
A connecting member joined to one end of the sleeve;
A caulking portion formed by caulking at least one of the one end portion of the sleeve and the connecting member;
The said crimping | crimped part is arrange | positioned in the position which differs in the circumferential direction with respect to the said ball groove. One of the one end of the sleeve and the connecting member is provided with a protruding portion protruding in the axial direction, and the other end of the one end of the sleeve and the connecting member is fitted with the protruding portion. A fitting part is provided,
The intermediate shaft according to claim 1, wherein the convex portion and the fitting portion are non-circular when viewed in the axial direction. The fitting portion is provided at one end of the sleeve,
The convex portion is provided on the connecting member,
The convex part and the fitting part are formed long in the axial direction view,
The ball groove is provided in each of the pair of long side portions in the fitting portion,
The intermediate shaft according to claim 2, wherein the crimping portion is provided on each of the pair of short sides in the fitting portion. The intermediate shaft according to claim 3, wherein the long side portion of the fitting portion is formed with a pair of flat portions that are disposed so as to sandwich the ball groove and abut against the convex portion. The intermediate shaft according to claim 1, wherein the one end portion of the sleeve and the connecting portion are welded. The intermediate shaft according to any one of claims 1 to 5, wherein a plurality of the caulking portions are provided and are arranged uniformly in the circumferential direction.

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