JP2005321058A - Yoke for universal joint - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a yoke for a universal joint in which sufficient strength can be secured even when the whole length of the yoke is short. <P>SOLUTION: From an upper free end of a hub 4, a straight flange 42 is formed to be extended in a tangent direction to the hub 4. From a lower free end of the hub 4, an L-shaped flange 43 is formed to be extended in parallel to the straight flange 42, and then bent at a right angle to the straight flange 42. On the inside 421 of the straight flange 42, a recessed engagement groove 44 is formed. The engagement groove 44 is formed by press work, and its depth L is set in plate thickness S3-2.5 mm or less. At an upper end of a folded part 432 of the L-shaped flange 43, a projection 45 to be engaged with the engagement groove 44 is formed. The projection 45 is, preferably, tightly engaged with the engagement groove 44 in the direction of groove length Q. It may be provided with a gap of 1 mm or less, if any. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a universal joint yoke, and more particularly to a universal joint yoke that is incorporated in a steering column device of a vehicle and transmits the rotation of a steering wheel to a steering gear.

  A universal joint yoke formed by bending a metal plate by plastic working has a tubular hub whose one end is coupled to a rotating shaft by serration or the like, and extends from the other end of the hub in parallel to the central axis of the hub. It is comprised from a pair of fork which has a bearing hole which connects an axis | shaft. A pair of flanges extend from the tubular hub, and the bolts inserted into the flanges are fastened with a predetermined torque, whereby the hub is fastened to the rotating shaft and the rotating torque is transmitted between the rotating shaft and the hub. I have to.

  When torque is applied to this universal joint during vehicle steering, and torque is transmitted to the hub via the cross shaft, the stress that tends to deform the free ends of the pair of flanges in a direction that is shifted parallel to the central axis of the hub Works. If this deformation of the flange is large, there is a problem that the steering feeling of the steering wheel deteriorates.

  Universal yokes disclosed in Patent Document 1, Patent Document 2, and Patent Document 3 are yokes that prevent such flange displacement. The universal joints disclosed in Patent Documents 1 to 3 are provided with flanges by alternately providing protrusions and notches along the central axis of the hub at the free end of the flange. The shift is prevented.

  However, in the universal joints of Patent Document 1 to Patent Document 3, in the case of a universal joint whose overall length in the central axis direction of the hub is short, the length of the projection and the notch in the central axis direction is also shortened. As a result, the steering feeling of the tearing wheel is not improved.

  In addition, the universal joint disclosed in Patent Document 4 is such that the free end of the flange is bent into an L shape and abutted against the other free end, and this abutting surface is brought into close contact with the tightening force of the bolt. Since the displacement of the flange is merely prevented by the frictional force of the abutting surface, the displacement of the flange in the direction of the central axis of the hub cannot be reliably prevented.

Japanese Utility Model Publication No. 3-15859 Japanese Utility Model Publication No. 4-11924 Japanese Patent Laid-Open No. 6-10959 Japanese Utility Model Publication No. 54-182755

  An object of the present invention is to provide a universal joint yoke capable of ensuring sufficient strength even when the yoke overall length is short.

  The above problem is solved by the following means. That is, the first invention is a universal joint yoke formed by plastic processing of a metal plate, the hub bent into a tubular shape to hold the rotating shaft, and the hub from one of the free ends of the hub. A linear flange extending in a substantially tangential direction, an engagement groove formed shallower than the thickness of the linear flange inside the linear flange, and extending substantially parallel to the linear flange from the other free end of the hub. After that, the L-shaped flange which is bent in the L-shape on the linear flange side and formed with the protrusion engaged with the engaging groove, between the parallel portion of the L-shaped flange and the linear flange The universal joint yoke is provided with a bolt that is inserted through the bolt and tightened in a direction in which the L-shaped flange and the linear flange approach each other.

  A second invention is a universal joint yoke formed by plastic processing of a metal plate, the hub bent into a tubular shape to hold a rotating shaft, and the hub from one of the free ends of the hub. A linear flange extending in the tangential direction, an engagement groove formed shallower than the thickness of the linear flange on the inner side of the linear flange, and tilted inward from the other free end of the hub with respect to the linear flange The L-shaped flange, which is bent into an L-shape on the linear flange side and formed with a protrusion that engages with the engaging groove, the inclined portion of the L-shaped flange, and the linear flange The universal joint yoke is provided with a bolt that is inserted between the L-shaped flange and the linear flange so as to be close to each other.

  According to a third invention, in the universal joint yoke according to the first or second invention, a plurality of the engagement grooves are formed inside the linear flange, and the L-shaped flange is formed. In the universal joint yoke, the same number of protrusions engage with the engaging groove.

  A fourth invention is a universal joint yoke formed by plastic processing of a metal plate, the hub bent into a tubular shape to hold a rotating shaft, and the hub from one of the free ends of the hub. A linear flange extending in a tangential direction, a protrusion formed below the thickness of the linear flange on the inner side of the linear flange, and extending substantially parallel to the linear flange from the other free end of the hub; An L-shaped flange which is bent in an L-shape on the linear flange side and formed with an engagement groove that engages with the protrusion, and is inserted between a parallel portion of the L-shaped flange and the linear flange; A universal joint yoke comprising a bolt for tightening an L-shaped flange and the linear flange in a direction approaching each other.

  A fifth invention is a universal joint yoke formed by plastic processing of a metal plate, the hub bent in a tubular shape to hold a rotating shaft, and the hub from one of the free ends of the hub. A linear flange extending in the tangential direction, a protrusion formed below the thickness of the linear flange on the inner side of the linear flange, and inclined from the other free end of the hub to the inner side of the linear flange. After extending, the L-shaped flange is bent into an L-shape on the linear flange side and formed with an engagement groove to be engaged with the protrusion, and the inclined portion of the L-shaped flange and the linear flange A universal joint yoke comprising bolts inserted between the L-shaped flange and the linear flange so as to approach each other.

According to a sixth invention, in the universal joint yoke according to the fourth or fifth invention, a plurality of the protrusions are formed inside the linear flange, and the same number formed on the L-shaped flange. The engagement groove engages with the engagement groove.

  In the universal joint yoke of the present invention, the groove depth of the engaging groove or the height of the protrusion is smaller than the plate thickness of the flange and does not penetrate the outside of the flange. Even in such a case, sufficient strength can be ensured.

* 1st Embodiment Hereinafter, embodiment of this invention is described based on drawing. FIG. 1 is a side view, partly in section, of a universal joint according to a first embodiment of the present invention. 2 is a cross-sectional view taken along line AA of FIG. 1, and FIG. 3 is a perspective view of the linear flange of FIG. 2 as viewed from below.

  As shown in FIGS. 1 to 3, the universal joint 1 according to the first embodiment of the present invention includes a pair of yokes 2 </ b> A and 2 </ b> B, and the left yoke 2 </ b> A is a rotating shaft 3 </ b> A such as a steering shaft. It is fixed to the right end by welding. On the other hand, the right yoke 2B is a universal joint yoke according to the first embodiment of the present invention, which is formed by pressing (plastic processing) a metal plate, and is used for the rotary shaft 3B such as an intermediate shaft. It is detachably attached to the male serration 31 at the left end. The yoke length M of the first embodiment is 41 mm to 62 mm.

  The yoke 2B is composed of a hub 4 bent into a tubular shape and a pair of forks 5A, 5B extending from the left end of the hub 4 to the left in parallel with the central axis of the hub 4. At the left end of the forks 5A, 5B, a concentric bearing hole 51 is formed orthogonal to the central axis of the hub 4, and a bottomed cylindrical bearing cup 53 is opposed to the opening of the bearing hole 51. The inner fitting is fixed in the state.

  Four shaft portions 55 perpendicular to the cross shaft are inserted into the bearing cup 53, and a needle bearing 52 is inserted between the inner peripheral surface of the bearing cup 53 and the outer peripheral surface of the shaft portion 55. The forks 5A and 5B are swung with a light force with respect to the shaft portion 55 of the cross shaft. The diameter of the shaft portion 55 is set to 9 mm to 10.6 mm, and the outer diameter of the needle bearing 52 is set to 14.6 mm to 16.6 mm.

  A bottomed insertion hole 56 is formed in the central portion of the shaft portion 55, and the resin thrust piece 54 inserted between the insertion hole 56 and the bottom surface of the bearing cup 53 is an opening end portion of the bearing cup 53. Therefore, even if the central axes of the yokes 2A and 2B are not on the same straight line, a transmission loss is generated between the yokes 2A and 2B. The rotational force can be transmitted without being generated.

  A female serration 41 is formed on the inner peripheral surface of the tubular hub 4, and the male serration 31 of the rotary shaft 3B is engaged with the female serration 41 to transmit rotational torque between the hub 4 and the rotary shaft 3B. can do.

  The hub 4 is formed with a linear flange 42 extending from a free end on the upper side of the hub 4 in a tangential direction of the hub 4 (a direction perpendicular to the bearing hole 51). Further, the free end on the lower side of the hub 4 extends in parallel to the linear flange 42 (the direction tangential to the hub 4 and perpendicular to the bearing hole 51), and then is perpendicular to the linear flange 42 side. An L-shaped flange 43 is formed that is bent in a straight line.

  As a material of the metal plate of the yoke 2B formed by press working, JIS hot rolled mild steel plate SPHC, SPHD, SPHE, or JIS automotive structural hot rolled steel plate SAPH310, SAPH370, SAPH400, SAPH440, etc. are used. The plate thickness of the metal plate is 5 to 7.2 mm.

  A concave engagement groove 44 is formed on the inner side 421 of the linear flange 42. The engagement groove 44 is formed by press working, and the groove depth L is formed to a plate thickness S3-2.0 mm or less in consideration of ease of forming by press working. Further, the groove width S1 is formed to a plate thickness S3 + 1.0 mm.

  On the upper end of the bent portion 432 of the L-shaped flange 43, a protrusion 45 that engages with the engagement groove 44 is formed. The protrusion 45 is preferably tightly fitted in the direction of the groove length Q of the engagement groove 44, and is preferably 1 mm or less even if a gap is provided. The groove length Q is longer than the length N at both ends of the groove, and the groove length Q is preferably twice the length N at both ends of the groove. The gap E between the upper surface 451 of the protrusion 45 and the bottom surface 441 of the engagement groove 44 is preferably 2.5 mm or less.

  A bolt hole 422 is formed in the linear flange 42 in parallel with the bearing hole 51, and an internal thread 433 is formed on the parallel part 431 of the L-shaped flange 43 on the same axis as the bolt hole 422, so that the bolt 6 is attached. It is screwed into the female screw 433 through the bolt hole 422. In order to increase the screw length of the female screw 433, a thickened portion 435 is formed outside the parallel portion 431 by upsetting or burring. The nominal dimension of the bolt 6 is M8 × 1.25.

  When the bolt 6 is tightened via the spring washer 61, the linear flange 42 and the L-shaped flange 43 are bent inward from the root portions 423 and 434, and the female serration 41 is strongly pressed against the male serration 31. 3B and the hub 4 adhere closely without a gap. The tightening torque of the bolt 6 is 20 to 30 N · m.

  By tightening the bolt 6, the gap E between the upper surface 451 of the protrusion 45 and the bottom surface 441 of the engagement groove 44 becomes zero, and the coupling rigidity between the protrusion 45 and the engagement groove 44 increases. During driving operation, when the vehicle steering load is applied to the universal joint 1 and the torque transmitted to the fork 2B via the shaft portion 55 of the cross shaft is transmitted to the hub 4, the linear flange 42, L-shape A stress acts to move the flanges 43 in the direction in which the flanges 43 are displaced in parallel to the central axis of the hub.

  However, the engagement between the engaging groove 44 of the linear flange 42 and the protrusion 45 of the L-shaped flange 43 prevents this movement, so that the linear flange 42 and the L-shaped flange 43 are not displaced. Good steering feeling of the steering wheel can be obtained.

  Moreover, since the torque at the time of a steering is hardly applied to the volt | bolt 6, since the nominal diameter of the volt | bolt 6 can be made small, the rotating diameter of the universal joint 1 can be made small. In the first embodiment, the groove depth L of the engaging groove 44 is shallower than the plate thickness of the linear flange 42 and does not penetrate the outside of the linear flange 42. Even when the strength is large and the yoke total length M is short, sufficient strength can be ensured.

  Further, in the steering column device with a column type electric power steering, since the auxiliary steering force applying portion is arranged on the steering wheel side with respect to the universal joint 1, the steering torque applied to the universal joint 1 is increased. It is preferable to apply the universal joint yoke of the present invention to a steering column device that requires high strength. Furthermore, since the yoke of the universal joint of the present invention can be easily formed by pressing, it can be manufactured at a lower cost than those formed by hot forging or cold forging.

* 2nd Embodiment Hereinafter, the 2nd Embodiment of this invention is described based on drawing. FIG. 4 is a side view, partly in section, of a universal joint according to the second embodiment of the present invention. In the following description, only a structural part different from the first embodiment will be described, and a duplicate description will be omitted.

  As shown in FIG. 4, the universal joint 1 according to the second embodiment of the present invention has two concave engagement grooves 44 </ b> A and 44 </ b> B formed on the inner side 421 of the linear flange 42. Two protrusions 45A and 45B that engage with the engaging grooves 44A and 44B are formed at the upper end of the bent portion 432. Since two engaging grooves and two protrusions are required, the manufacturing cost is slightly higher than in the first embodiment. Other structures are the same as those of the first embodiment.

* Third Embodiment Hereinafter, a third embodiment of the present invention will be described with reference to the drawings. FIG. 5 is a side view, partly in section, of a universal joint according to the third embodiment of the present invention. 6 is a cross-sectional view taken along the line BB in FIG. 5, and FIG. 7 is a cross-sectional view taken along the line CC in FIG. In the following description, only a structural part different from the first embodiment will be described, and a duplicate description will be omitted.

  The universal joint 1 according to the third embodiment of the present invention is obtained by reversing the flange on which the protrusion 45 and the engagement groove 44 are formed. The protrusion 45 is formed on the linear flange 42 side, and is L-shaped. An engagement groove 44 that engages with the protrusion 45 is formed at the upper end of the bent portion 432 of the flange 43. The groove width S2 is smaller than the plate thickness S3. Thereby, as shown in FIG. 6, the rotation diameter D of the universal joint 1 can be made small. Other structures are the same as those of the first embodiment.

  In the third embodiment, similarly to the second embodiment, a plurality of protrusions 45 and engagement grooves 44 may be formed.

* Fourth Embodiment Hereinafter, a fourth embodiment of the present invention will be described with reference to the drawings. FIG. 8 is a side view showing a cross section of a part of a universal joint according to a fourth embodiment of the present invention. 9 is a cross-sectional view taken along the line DD of FIG. In the following description, only a structural part different from the first embodiment will be described, and a duplicate description will be omitted.

  The universal joint 1 according to the fourth embodiment of the present invention is obtained by reversing the vertical positions of the linear flange 42 and the L-shaped flange 43. That is, the linear flange 42 is formed from the lower free end of the hub 4 in the tangential direction of the hub 4 (direction perpendicular to the bearing hole 51). In addition, the free end on the upper side of the hub 4 extends parallel to the linear flange 42 (the tangential direction of the hub 4 and perpendicular to the bearing hole 51), and then is perpendicular to the linear flange 42 side. A bent L-shaped flange 43 is formed.

  The point that the engaging groove 44 is formed on the linear flange 42 side and the protrusion 45 that engages with the engaging groove 44 is formed at the lower end of the bent portion 432 of the L-shaped flange 43 is the same as in the first embodiment. Are the same. The point that the groove width S2 is smaller than the plate thickness S3 is the same as in the third embodiment. Further, the tip corner portion 424 of the linear flange 42 is not chamfered. Thereby, manufacturing cost can be made cheaper than the first embodiment. In the fourth embodiment, the thickening portion 435 provided in the first to third embodiments is omitted.

  The yoke 2A connected to the yoke 2B is made of cold forging. The yoke to be paired with the universal joint yoke 2B of the present invention is a combination of two universal joint yokes 2B of the present invention or a combination of a buffer yoke with rubber inserted between the yoke and the rotating shaft. There are various modifications, and the like, and the present invention is not limited to the embodiments.

* Fifth Embodiment Hereinafter, a fifth embodiment of the present invention will be described with reference to the drawings. FIG. 10 is a cross-sectional view of a universal joint according to a fifth embodiment of the present invention, and is a cross-sectional view corresponding to the DD cross-sectional view of FIG. In the following description, only a structural part different from the first embodiment will be described, and a duplicate description will be omitted.

  The fifth embodiment of the present invention is characterized in that after the L-shaped flange 43 extends while inclining with respect to the linear flange 42, the L-shaped flange 43 is bent in an L-shape on the linear flange side 42. is there. That is, instead of the parallel portion 431 of the first to fourth embodiments, the inclined portion 436 extends from the free end of the hub 4 and the bent portion 432 extends in an L shape from the inclined portion 436. The angle is small and it can be bent easily. Also, since the bending radius R is larger than the bending radii of the first to fourth embodiments, it is easy to form even a metal plate of a high strength material or a metal plate of a small elongation material. It becomes.

It is the side view which made some cross sections of the universal joint of the 1st Embodiment of this invention. It is AA sectional drawing of FIG. It is the perspective view which looked at the linear flange 42 of FIG. 2 from the downward direction. It is the side view which made a part of universal joint of the 2nd Embodiment of this invention the cross section. It is the side view which made a section of a universal joint of a 3rd embodiment of the present invention a section. It is BB sectional drawing of FIG. It is CC sectional drawing of FIG. It is the side view which made a part of universal joint of the 4th Embodiment of this invention the cross section. It is DD sectional drawing of FIG. It is sectional drawing which shows the universal joint of the 5th Embodiment of this invention, and is equivalent to the DD cross section of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Universal joint 2A, 2B Yoke 3A, 3B Rotating shaft 31 Male serration 4 Hub 41 Female serration 42 Linear flange 421 Inner 422 Bolt hole 423 Root part 424 Tip corner part 43 L-shaped flange 431 Parallel part 432 Bending part 433 Female screw 434 Root portion 435 Thickened portion 436 Inclined portion 44 Engaging groove 441 Bottom surface 45 Projection 451 Top surface 5A, 5B Fork 51 Bearing hole 52 Needle bearing 53 Bearing cup 54 Thrust piece 55 Shaft portion 56 Insertion hole 6 Bolt 61 Spring washer

Claims (6)

A universal joint yoke formed by plastic processing of a metal plate,
A hub folded into a tube to hold the axis of rotation;
A linear flange extending from one of the free ends of the hub in a substantially tangential direction of the hub;
An engagement groove formed shallower than the thickness of the linear flange inside the linear flange;
An L-shaped flange having a protrusion that extends substantially parallel to the linear flange from the other free end of the hub and is then bent into an L-shape on the linear flange side to engage with the engaging groove. ,
A universal joint yoke comprising a bolt inserted between a parallel portion of the L-shaped flange and the linear flange and tightened in a direction in which the L-shaped flange and the linear flange approach each other. . A universal joint yoke formed by plastic processing of a metal plate,
A hub folded into a tube to hold the axis of rotation;
A linear flange extending from one of the free ends of the hub in a substantially tangential direction of the hub;
An engagement groove formed shallower than the thickness of the linear flange inside the linear flange;
After extending from the other free end of the hub so as to incline with respect to the linear flange, the hub is bent into an L shape on the linear flange side, and a projection that engages with the engagement groove is formed. L-shaped flange,
A universal joint yoke comprising a bolt inserted between an inclined portion of the L-shaped flange and the linear flange, and tightened in a direction in which the L-shaped flange and the linear flange approach each other. . In the universal joint yoke according to claim 1 or 2,
A plurality of the engaging grooves are formed inside the linear flange,
A universal joint yoke, wherein the same number of protrusions formed on the L-shaped flange engage with the engaging groove. A universal joint yoke formed by plastic processing of a metal plate,
A hub folded into a tube to hold the axis of rotation;
A linear flange extending from one of the free ends of the hub in a substantially tangential direction of the hub;
A protrusion formed below the thickness of the linear flange inside the linear flange,
An L-shaped flange having an engagement groove that extends substantially parallel to the linear flange from the other free end of the hub and is then bent to an L-shape on the linear flange side to engage with the protrusion;
A universal joint yoke comprising a bolt inserted between a parallel portion of the L-shaped flange and the linear flange and tightened in a direction in which the L-shaped flange and the linear flange approach each other. . A universal joint yoke formed by plastic processing of a metal plate,
A hub folded into a tube to hold the axis of rotation;
A linear flange extending from one of the free ends of the hub in a substantially tangential direction of the hub;
A protrusion formed below the thickness of the linear flange inside the linear flange,
After extending inward from the other free end of the hub with respect to the linear flange, it is bent into an L shape on the linear flange side, and an engagement groove is formed to engage with the protrusion. L-shaped flange,
A universal joint yoke comprising a bolt inserted between an inclined portion of the L-shaped flange and the linear flange, and tightened in a direction in which the L-shaped flange and the linear flange approach each other. . In the universal joint yoke according to claim 4 or 5,
A plurality of the protrusions are formed inside the linear flange,
A universal joint yoke, wherein the same number of engaging grooves formed in the L-shaped flange engage with the engaging grooves.

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