JP2008303980A - Joint - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a joint having improved shaft joint rigidity without increasing the number of components. <P>SOLUTION: When bolts 8, 8 are threaded to a first threaded hole 481 and a second threaded hole 482, respectively, a first flange 46 and a second flange 47 are fastened to each other. The first threaded hole 481 and the second threaded hole 482 are arranged at symmetrical positions across a female serration 45. Thus, clearances δ1, δ2 between a first cut split 431 and a second cut split 432 are uniformly narrowed, a male serration 71 of a shaft 7 is engaged with the female serration 45 of a joint cylinder portion 41 to permit the transmission of rotating torque, and the outer peripheries of the bolts 8, 8 are engaged with an annular groove 72 of the shaft 7 to prevent the come-off of the shaft 7 from the serration 45. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a joint, and more particularly, to a joint that connects shafts that transmit rotation of a steering shaft of a steering device.

  In a steering device that steers the front wheels of a vehicle, the movement of a steering shaft that is rotated by the operation of a steering wheel is transmitted to an input shaft of a steering gear through a universal joint.

  The movement of the steering wheel is transmitted to the steering gear via a steering shaft and an intermediate shaft that are rotatably provided in the steering column, and the direction of the wheel is steered by the steering gear. Normally, the steering shaft and the input shaft of the steering gear cannot be provided on the same straight line.

  For this reason, conventionally, as shown in Patent Document 1, an intermediate shaft is provided between the steering shaft and the input shaft to the steering gear, the end of the intermediate shaft and the steering shaft, and the end of the intermediate shaft and the steering shaft. By connecting the end portion of the input shaft of the gear via a universal joint, power can be transmitted between the steering shaft and the input shaft that do not exist on the same straight line.

  In recent years, there has been an increasing number of column assist type electric power steering devices in which an assist device for applying a steering assist force to a steering shaft is provided between an intermediate shaft and a steering wheel.

  In such column assist type electric power steering, since the rotational torque applied to the intermediate shaft is increased, it is necessary to increase the coupling rigidity of the coupling portion between the intermediate shaft and the universal joint.

  The universal joint shown in Patent Document 2 uses two bolts to couple the coupling cylinder portion of the universal joint yoke and the shaft. In the universal joint shown in Patent Document 2, the number of parts increases because the coupling cylinder part of the yoke and the shaft are tightened with bolts through a thin plate-like strap formed as a separate part from the coupling cylinder part. As a result, the manufacturing cost may increase.

Japanese Patent Laid-Open No. 4-125314 British Patent Application No. 1233828

  An object of the present invention is to provide a joint that does not increase the number of parts and has high coupling rigidity with a shaft.

  The above problem is solved by the following means. That is, the first invention is formed with a coupling cylinder portion having a hole for fitting a shaft to the proximal end portion so that rotational torque can be transmitted, and the coupling cylinder portion sandwiching the hole portion, respectively. A first flange portion formed by a pair of left and right flange portions provided integrally with the coupling cylinder portion across the first slit and the first slit and the second slit penetrating the hole portion; A second flange portion formed by a pair of left and right flange portions and formed on either the left or right flange portion of the first flange portion, which is provided integrally with the coupling cylinder portion across the second slit. The first through hole, the second through hole formed in either the left or right flange portion of the second flange portion, the first flange portion in the left or right flange portion of the first flange portion, To screw the bolt inserted through the through hole In order to screw the bolt inserted through the second through hole into the first screw hole formed concentrically with the first through hole or the left or right flange part of the second flange part. The joint has a second screw hole formed concentrically with the second through hole.

  According to a second aspect of the present invention, in the joint according to the first aspect, the first through hole and the second through hole are formed at symmetrical positions across the hole portion. It is.

  According to a third aspect of the present invention, a coupling cylinder part having a hole part for fitting a shaft so that rotational torque can be transmitted to a proximal end part is formed, and the coupling cylinder part is formed with the hole part interposed therebetween, A first flange portion formed by a pair of left and right flange portions provided integrally with the coupling cylinder portion with the first slit and the second slit penetrating through the hole portion interposed therebetween, and the first flange portion; A second flange portion formed by a pair of left and right flange portions and a left or right flange portion of the first flange portion, which is provided integrally with the coupling cylinder portion across two cuts. 1 through hole, a second through hole formed in either the left or right flange portion of the second flange portion, and the first through hole in the left or right flange portion of the first flange portion. In order to insert the bolt inserted through the hole, the first In order to insert a bolt inserted from the second through-hole into a third through-hole formed concentrically with the through-hole, the left or right flange portion of the second flange portion, the second through-hole A fourth through-hole formed concentrically with the through-hole, and a nut that is screwed into each of the bolts and fastens the bolt to the first flange portion and the second flange portion, respectively. It is a joint.

  According to a fourth aspect of the present invention, in the joint according to the third aspect, the first through hole and the second through hole are formed at symmetrical positions with the hole interposed therebetween. It is.

  According to a fifth aspect of the present invention, in the joint according to any one of the first to fourth aspects of the invention, the coupling cylinder portion includes a first concave portion and a second concave portion that do not penetrate the hole portion. The joint is characterized in that the first slit is formed in the first recess, and the second slit is formed in the second recess. .

  A sixth invention is a joint according to the fifth invention, wherein the first recess and the second recess are substantially V-shaped recesses.

  According to a seventh invention, in the joint of any one of the first to fourth inventions, a female serration that engages with the male serration of the shaft and transmits rotational torque is formed in the hole. It is the coupling characterized by having.

  According to an eighth aspect of the present invention, in the joint according to any one of the first to fourth aspects, the hole includes two pieces that engage with two planes of the shaft and transmit rotational torque. The joint is characterized in that a flat surface is formed.

  A ninth invention is a joint according to any one of the first to fourth inventions, wherein the shaft is formed with a groove engaging with the bolt.

  A tenth aspect of the invention is a joint according to the ninth aspect of the invention, wherein the bolt is engaged with the groove of the shaft when the bolt passes through the hole of the coupling cylinder portion.

  The eleventh invention is characterized in that, in the joint according to any one of the first to fourth inventions, at least one of the bolts is a stepped bolt in which a step portion is formed. It is a joint.

  In a twelfth aspect of the joint according to any one of the first to fourth aspects of the present invention, the first split and the second split are provided at the radially outer ends of the first split and the second split. The joint is characterized in that a gap smaller than the slit gap is formed.

  A thirteenth aspect of the invention is the joint according to any one of the first to fourth aspects of the invention, wherein the coupling tube portion has a bearing hole for pivotally supporting the cross shaft on the side opposite to the hole portion. A joint having a pair of arms formed integrally.

  A fourteenth aspect of the invention is the joint according to the thirteenth aspect of the invention, wherein the hole is formed as a blind hole that does not penetrate the bottom of the arm.

  A fifteenth aspect of the invention is a joint according to the thirteenth aspect of the invention, wherein the first and second slits are formed in a shape that does not penetrate the bottom of the arm portion. .

  A sixteenth aspect of the present invention is the joint according to any one of the first to fourth aspects, wherein the joint is a universal joint that connects the intermediate shaft and the steering shaft or the intermediate shaft and the steering gear. An assist device for applying a steering assist force to the steering shaft is provided between the intermediate shaft and the steering wheel.

  The seventeenth invention is a joint characterized in that the joint of any one of the first to fourth inventions is formed by forging.

  The joint of the present invention is formed with a coupling cylinder part provided with a hole part for fitting a shaft so that rotational torque can be transmitted to the proximal end part, and a coupling cylinder part with the hole part sandwiched between them. A first flange portion that is formed integrally with the coupling cylinder portion with the first slit and the second slit, and a pair of left and right flange portions sandwiching the first slit, and a second slit. A second flange portion that is provided integrally with the coupling cylinder portion and sandwiched between a pair of left and right flange portions; and a first through hole formed in either the left or right flange portion of the first flange portion; The second through hole formed in either the left or right flange portion of the second flange portion and the bolt inserted from the first through hole into the left or right flange portion of the first flange portion A first screw hole formed concentrically with the first through hole for screwing A second screw hole formed concentrically with the second through hole in order to screw the bolt inserted from the second through hole into the left or right flange part of the second flange part. Have.

  Accordingly, since the first flange portion and the second flange portion formed integrally with the coupling cylinder portion are tightened using bolts, the coupling rigidity between the shaft and the coupling cylinder portion is large, and the number of parts increases. The increase in manufacturing cost is small.

  Embodiments 1 to 10 of the present invention will be described below with reference to the drawings.

  FIG. 1 is a side view showing a part of a steering apparatus including a joint according to the present invention, and shows an embodiment applied to an electric power steering apparatus having a steering assisting portion.

  As shown in FIG. 1, the steering device of the present invention includes a steering shaft 12 on which a steering wheel 11 can be mounted on the rear side of the vehicle body (right side of FIG. 1), a steering column 13 inserted through the steering shaft 12, and the steering wheel. An assist device (steering assisting portion) 20 for applying assist torque to the shaft 12 and a steering gear connected to the front side of the vehicle body of the steering shaft 12 (left side in FIG. 1) via a rack / pinion mechanism (not shown). 30.

  The steering shaft 12 is spline-fitted between a female steering shaft 12A and a male steering shaft 12B so as to be able to transmit rotational torque and to be relatively movable in the axial direction. Therefore, when the female steering shaft 12A and the male steering shaft 12B collide, the spline fitting portion moves relative to each other so that the total length can be shortened.

  Further, the cylindrical steering column 13 inserted through the steering shaft 12 combines the outer column 13A and the inner column 13B so that they can be telescopically moved. It has a so-called collapsible structure in which the entire length is shortened while absorbing water.

  The vehicle body front side end portion of the inner column 13B is press-fitted and fixed to the vehicle body rear side end portion of the gear housing 21. Further, the front end portion of the male steering shaft 12B on the vehicle body is passed through the inside of the gear housing 21 and connected to the rear end portion of the assist device 20 on the rear side of the input shaft (not shown).

  The steering column 13 is supported by a support bracket 14 at a middle portion thereof on a part of the vehicle body 18 such as a lower surface of the dashboard. Further, a locking portion (not shown) is provided between the support bracket 14 and the vehicle body 18, and when an impact in a direction toward the front side of the vehicle body is applied to the support bracket 14, the support bracket 14 is locked to the locking bracket 14. It moves away from the vehicle and moves to the front side of the vehicle.

  The upper end portion of the gear housing 21 is also supported on a part of the vehicle body 18. In this embodiment, the height position of the steering wheel 11 and the longitudinal position of the vehicle body can be freely adjusted by providing a tilt mechanism and a telescopic mechanism. Such a tilt mechanism and a telescopic mechanism are well known in the art and are not characteristic features of the present invention, and thus detailed description thereof is omitted.

  The output shaft 23 protruding from the end face on the front side of the vehicle body of the gear housing 21 is connected to the rear end portion of the intermediate shaft 16 via the universal joint 15. Further, the input shaft 31 of the steering gear 30 is connected to the front end portion of the intermediate shaft 16 via another universal joint 17. The intermediate shaft 16 is fitted on the vehicle body front side of the male intermediate shaft (male shaft) 16A on the vehicle body rear side of the female intermediate shaft (female shaft) 16B, so that rotational torque can be transmitted and relative movement in the axial direction is possible. Is fitted.

  A pinion (not shown) is coupled to the input shaft 31. A rack (not shown) fitted in the steering gear 30 so as to be reciprocally slidable meshes with the pinion, and the rotation of the steering wheel 11 moves the tie rod 32 to steer a wheel (not shown).

  A case 261 of an electric motor 26 is fixed to the gear housing 21 of the assist device 20, and a worm is coupled to a rotating shaft (not shown) of the electric motor 26. A worm wheel (not shown) is attached to the output shaft 23, and the worm of the rotating shaft of the electric motor 26 is engaged with the worm wheel.

  A torque sensor (not shown) is provided around an intermediate portion of the axial length of the output shaft 23. The direction and magnitude of torque applied from the steering wheel 11 to the steering shaft 12 is detected by a torque sensor.

  The electric motor 26 is driven according to the detected value of the torque sensor, and auxiliary torque is generated in a predetermined direction in a predetermined direction on the output shaft 23 via a speed reduction mechanism composed of a worm and a worm wheel.

  2A and 2B show a universal joint according to the first embodiment of the present invention applied to the universal joints 15 and 17 of FIG. 1, wherein FIG. 2A is a cross-sectional view taken along the line A-A in FIG. It is. 3A is a cross-sectional view showing a state where the bolt and the shaft are removed from FIG. 2A, FIG. 3B is a front view showing the shaft of FIG. 2, and FIG. 3C is FIG. It is BB sectional drawing of).

  As shown in FIGS. 2 and 3, the universal joint of the first embodiment includes yokes 4 and 4 having bifurcated arm portions 42 and 42 and a cross shaft 6 that couples the bifurcated arm portions 42 and 42 to each other. It consists of Although not shown, the arm portions 42 and 42 are formed with a pair of circular holes (bearing holes), and a bearing for fitting with the cross shaft 6 is inserted therein.

  The yoke 4 is provided with a substantially rectangular coupling cylinder portion 41 at the proximal end portion, and an axial center of the coupling cylinder portion 41 (the center in the left and right and vertical directions in FIG. Female serrations (holes) 45 for fitting 7 (male intermediate shaft 16A, female intermediate shaft 16B, output shaft 23, input shaft 31 and the like in FIG. 1) are formed.

  As shown in FIGS. 2 (A) and 3 (A), the coupling cylinder portion 41 extends in the vertical direction of FIGS. 2 (A) and 3 (A) with the female serration 45 interposed therebetween, and the female serration 45. A first cut 431 and a second cut 432 are formed so as to pass through. The gaps δ1 and δ2 of the first cut 431 and the second cut 432 are formed with the same dimensions.

  A first flange portion 46 including a left flange portion 461 and a right flange portion 462 is formed integrally with the coupling cylinder portion 41 with the first slit 431 interposed therebetween. In addition, a second flange portion 47 including a left flange portion 471 and a right flange portion 472 is formed integrally with the coupling cylinder portion 41 with the second slit 432 interposed therebetween.

  A first screw hole 481 is formed in the left flange portion 461 of the first flange portion 46 in a direction perpendicular to the flange surface (the left-right direction in FIGS. 2A and 3A). . Further, the left flange portion 471 of the second flange portion 47 has a female serration 45 sandwiched in a direction perpendicular to the flange surface (left and right direction in FIG. 2A and FIG. A second screw hole 482 is formed at a position symmetrical to the screw hole 481.

A first through hole 491 is formed in the right flange portion 462 of the first flange portion 46 concentrically with the first screw hole 481. A second through hole 492 is formed in the right flange portion 472 of the second flange portion 47 concentrically with the second screw hole 482. Therefore, if the bolts 8 and 8 are inserted into the first through hole 491 and the second through hole 492, respectively, and the bolts 8 and 8 are rotated, the bolt 8 is inserted into the first screw hole 481 and the second screw hole 482. , 8 are screwed together.
The first through hole 491, the second through hole 492, the first screw hole 481, and the second screw hole 482 pass through the female serration 45.

  When the bolts 8 and 8 are screwed into the first screw hole 481 and the second screw hole 482, the first flange portion 46 and the second flange portion 47 are tightened. Since the first screw hole 481 and the second screw hole 482 are arranged at symmetrical positions across the female serration 45, the gaps δ1, δ2 between the first cut 431 and the second cut 432 are uniformly narrowed. The inner diameter of the female serration 45 is reduced, and the outer periphery of the shaft 7 is strongly tightened.

  As shown in FIGS. 2A, 3 </ b> B, and 3 </ b> C, a male serration 71 that engages with the female serration 45 is formed on the outer periphery of the end of the shaft 7. An annular groove 72 is formed on the outer periphery of the end of the shaft 7. The annular groove 72 is parallel to the axis of the shaft 7, and an arbitrary planar shape passing through the axis of the shaft 7 is formed in a convex arc shape toward the axis of the shaft 7.

  Therefore, when the bolts 8 and 8 are inserted into the first through hole 491 and the second through hole 492, the male serration 71 of the shaft 7 is serrated and engaged with the female serration 45 of the coupling cylinder portion 41, and rotational torque is transmitted. It becomes possible. At the same time, since the outer peripheries of the bolts 8 and 8 pass through the female serration 45, the outer peripheries of the bolts 8 and 8 engage with the annular groove 72 of the shaft 7 and the shaft 7 does not come out of the female serration 45.

  In the universal joint according to the first embodiment of the present invention, the first flange portion 46 and the second flange portion 47 formed integrally with the yoke 4 are fastened by using bolts 8 and 8 respectively. Therefore, the coupling rigidity between the shaft 7 and the coupling cylinder portion 41 of the yoke 4 is large, the number of parts is not increased, and the increase in manufacturing cost is small.

  Next, a second embodiment of the present invention will be described. FIG. 4 (A) is a view corresponding to FIG. 3 (A) showing a universal joint according to Embodiment 2 of the present invention. In the following description, only structural portions and operations different from the above embodiment will be described, and redundant description will be omitted. Further, the same parts will be described with the same numbers.

  The second embodiment is a modification of the first embodiment, and the first slit 431 and the second slit 432 are spaced at the outer ends in the radial direction of the first slit 431 and the second slit 432. In this example, gaps smaller than δ1 and δ2 are formed. Thus, when the tightening force with which the bolts 8 and 8 tighten the first flange portion 46 and the second flange portion 47 reaches a predetermined value, there is no gap and the tightening force is regulated to the predetermined value. .

  As shown in FIG. 4 (A), a rectangular protrusion 462A projecting into the first slit 431 is provided at the radially outer end of the first slit 431 (the upper end of FIG. 4 (A)). A right flange portion 462 of the portion 46 is formed. In addition, a rectangular protrusion 472A that protrudes into the second slit 432 extends from the right flange portion 472 of the second flange portion 47 at the radially outer end of the second slit 432 (the lower end of FIG. 4A). Is formed.

Accordingly, the gap δ3 between the rectangular protrusion 462A and the left flange portion 461 of the first flange portion 46 is set to a size smaller than the gap δ1 of the first slit 431. The gap δ4 between the rectangular protrusion 472A and the left flange portion 471 of the second flange portion 47 is set to a size smaller than the gap δ2 of the second slit 432. The gaps δ3 and δ4 are formed with the same dimensions.

  Therefore, if the bolts 8 and 8 are inserted into the first through hole 491 and the second through hole 492, respectively, and the bolts 8 and 8 are rotated, the bolt 8 is inserted into the first screw hole 481 and the second screw hole 482. , 8 are screwed together, and the first flange portion 46 and the second flange portion 47 are tightened. The gaps δ3 and δ4 are uniformly narrowed, the inner diameter of the female serration 45 is reduced, and the outer periphery of the shaft 7 is strongly tightened.

  When the tightening force for tightening the flange portions 46 and 47 reaches a predetermined value, the gaps δ3 and δ4 disappear, the rectangular projection 462A and the left flange portion 461 of the first flange portion 46 come into close contact, and the rectangular projection 472A and the second flange The left flange portion 471 of the portion 47 is in close contact with the bolts 8 and 8 so that the bolts 8 and 8 cannot be tightened any further. For this reason, the coupling rigidity between the shaft 7 and the coupling cylinder portion 41 of the yoke 4 can be reliably set to a predetermined size.

  Next, a third embodiment of the present invention will be described. FIG. 4 (B) is a view corresponding to FIG. 3 (A) showing a universal joint according to Embodiment 3 of the present invention. In the following description, only structural portions and operations different from the above embodiment will be described, and redundant description will be omitted. Further, the same parts will be described with the same numbers.

  The third embodiment is a modification of the second embodiment, in which the first slit 431 and the second slit 432 have a gap between the first slit 431 and the second slit 432 at the outer ends in the radial direction. In this example, gaps smaller than δ1 and δ2 are formed, and rectangular protrusions are formed from both the left and right flange portions of the first flange portion 46 and the second flange portion 47.

  As shown in FIG. 4B, a rectangular protrusion 462A protruding into the first slit 431 is provided at the radially outer end of the first slit 431 (the upper end of FIG. 4B). A right flange portion 462 of the portion 46 is formed. In addition, a rectangular protrusion 461A that protrudes into the first slit 431 is also formed from the left flange portion 461 of the first flange portion 46.

  In addition, a rectangular protrusion 472A that protrudes into the second slit 432 extends from the right flange portion 472 of the second flange portion 47 at the radially outer end of the second slit 432 (the lower end of FIG. 4B). Is formed. In addition, a rectangular protrusion 471 A that protrudes into the second slit 432 is also formed from the left flange portion 471 of the second flange portion 47.

  Accordingly, the gap δ5 between the rectangular protrusion 462A and the rectangular protrusion 461A is set to a size smaller than the gap δ1 of the first slit 431. In addition, the gap δ6 between the rectangular protrusion 472A and the rectangular protrusion 471A is set to a size smaller than the gap δ2 of the second slit 432. The gaps δ5 and δ6 are formed with the same dimensions.

  Therefore, if the bolts 8 and 8 are inserted into the first through hole 491 and the second through hole 492, respectively, and the bolts 8 and 8 are rotated, the bolt 8 is inserted into the first screw hole 481 and the second screw hole 482. , 8 are screwed together, and the first flange portion 46 and the second flange portion 47 are tightened. The gaps δ5 and δ6 are uniformly narrowed, the inner diameter of the female serration 45 is reduced, and the outer periphery of the shaft 7 is strongly tightened.

  When the tightening force for tightening the flange portions 46 and 47 reaches a predetermined value, the gaps δ5 and δ6 disappear, the rectangular protrusions 462A and the rectangular protrusions 461A come into close contact, the rectangular protrusions 472A and the rectangular protrusions 471A come into close contact, and the bolt 8 , 8 is restricted so that it cannot be tightened. For this reason, the coupling rigidity between the shaft 7 and the coupling cylinder portion 41 of the yoke 4 can be reliably set to a predetermined size.

  Next, a fourth embodiment of the present invention will be described. FIG. 5 shows a universal joint according to a fourth embodiment of the present invention, (A) is a view corresponding to FIG. 2 (A), (B) is a front view showing the axis of (A), and (C) is C of (B). It is -C sectional drawing. In the following description, only structural portions and operations different from the above embodiment will be described, and redundant description will be omitted. Further, the same parts will be described with the same numbers.

  The fourth embodiment is a modification of the first embodiment, and is an example in which the first screw hole 481 and the second screw hole 482 are changed to through holes and bolts are fastened to the flange portion with nuts.

  As shown in FIG. 5A, a first through hole 491 is formed in the right flange portion 462 of the first flange portion 46 in a direction perpendicular to the flange surface (left and right direction in FIG. 5A). Is formed. Further, the right flange portion 472 of the second flange portion 47 has a female serration 45 sandwiched in a direction perpendicular to the flange surface (left and right direction in FIG. 5A) with respect to the first through hole 491. A second through hole 492 is formed at a symmetrical position.

  A third through hole 493 is formed in the left flange portion 461 of the first flange portion 46 concentrically with the first through hole 491. Further, a fourth through hole 494 is formed in the left flange portion 471 of the second flange portion 47 concentrically with the second through hole 492. Accordingly, the bolts 8 and 8 are inserted into the first through hole 491 and the second through hole 492, respectively, and the bolts 8 and 8 are protruded from the third through hole 493 and the fourth through hole 494.

  Next, when the nuts 81, 81 are screwed into the bolts 8, 8, the first flange portion 46 and the second flange portion 47 are tightened, and the gap δ 1 between the first cut 431 and the second cut 432, δ2 is uniformly narrowed, the inner diameter of the female serration 45 is reduced, and the outer periphery of the shaft 7 is strongly tightened.

  As shown in FIGS. 5B and 5C, a male serration 71 that engages with the female serration 45 is formed on the outer periphery of the end of the shaft 7. Grooves 73 and 73 are formed on the outer periphery of the end portion of the shaft 7. The grooves 73, 73 are formed at positions 180 degrees out of phase on the outer periphery of the end of the shaft 7, and are parallel to the shaft center of the shaft 7 and have a single planar shape passing through the shaft center of the shaft 7. It is formed in the shape of a convex arc toward the axis.

  Accordingly, the bolts 8 and 8 are respectively inserted into the first through hole 491 and the second through hole 492, the bolts 8 and 8 are protruded from the third through hole 493 and the fourth through hole 494, and the nut 81, When 81 is screwed onto the bolts 8 and 8, the male serration 71 of the shaft 7 is serrated to the female serration 45 of the coupling cylinder portion 41, and the rotational torque can be transmitted. Further, the outer circumferences of the bolts 8 and 8 engage with the grooves 73 and 73 of the shaft 7, respectively, so that the shaft 7 does not come out of the female serration 45.

  Next, a fifth embodiment of the present invention will be described. FIG. 6 (A) is a view equivalent to FIG. 3 (A) showing a universal joint of Embodiment 5 of the present invention, FIG. 6 (B) is a front view showing a shaft fitted in FIG. 6 (A), and FIG. FIG. 6C is a sectional view taken along the line DD in FIG. In the following description, only structural portions and operations different from the above embodiment will be described, and redundant description will be omitted. Further, the same parts will be described with the same numbers.

  The fifth embodiment is a modification of the first embodiment, and is an example in which two planes are formed on the inner peripheral surface of the coupling cylinder portion 41 of the yoke 4 instead of the female serration 45 of the first embodiment.

  As shown in FIG. 6 (A), shafts (male intermediate shaft 16A, female intermediate shaft 16B, output shaft 23, input shaft 31 and the like in FIG. 1) 7 are provided on the inner peripheral surface of the coupling cylinder portion 41 of the yoke 4. Two planes 451 and 451 parallel to each other for fitting are formed.

  As shown in FIGS. 6B and 6C, on the outer periphery of the end portion of the shaft 7, two planes 74 and 74 that are engageable with the two planes 451 and 451 and are parallel to each other are formed. ing. Grooves 73 and 73 are formed on the outer periphery of the end portion of the shaft 7. The grooves 73, 73 are formed at positions 180 degrees out of phase on the outer periphery of the end of the shaft 7, and are parallel to the shaft center of the shaft 7 and have a single planar shape passing through the shaft center of the shaft 7. It is formed in the shape of a convex arc toward the axis.

  Therefore, when the bolts 8 and 8 are screwed into the first screw hole 481 and the second screw hole 482, the first flange portion 46 and the second flange portion 47 are tightened, and the first slit 431, The gaps δ1 and δ2 of the two slits 432 are evenly narrowed, the distance between the two planes 451 and 451 is reduced, the two planes 74 and 74 of the shaft 7 are strongly tightened, and the rotational torque can be transmitted. Further, the outer circumferences of the bolts 8 and 8 engage with the grooves 73 and 73 of the shaft 7, respectively, so that the shaft 7 does not come out of the coupling cylinder portion 41.

  Next, a sixth embodiment of the present invention will be described. FIG. 7: shows the universal joint of Example 6 of this invention, (A) is EE sectional drawing of (B), (B) is a front view of a universal joint. In the following description, only structural portions and operations different from the above embodiment will be described, and redundant description will be omitted. Further, the same parts will be described with the same numbers.

  The sixth embodiment is a modification of the first embodiment, and is an example in which the phase of the flange surface of the coupling cylinder portion 41 and the arm portions 42 and 42 is changed by 90 degrees.

  As shown in FIGS. 7A and 7B, the yokes 4 and 4 of the universal joint of the sixth embodiment are provided with flange surfaces (first slits 431 and 431) of the first flange portion 46 and the second flange portion 47, respectively. In addition, the arm portions 42 and 42 are formed to be bifurcated in a direction perpendicular to the second slit 432), and the bifurcated arm portions 42 and 42 are connected to each other by the cross shaft 6. Although not shown, a pair of circular holes (bearing holes) are formed in the arm portions 42 and 42 as in the first embodiment, and bearings for fitting with the cross shaft 6 are inserted.

  Next, a seventh embodiment of the present invention will be described. FIG. 8 is a component diagram showing a universal joint yoke 4 according to a seventh embodiment of the present invention. FIG. 8A is a sectional view taken along line FF in FIG. 8B, FIG. 8B is a front view, and FIG. ) And (D) are bottom views of (B).

  The universal joint yoke 4 of Example 7 of the present invention is formed by cutting a round bar-shaped material into a predetermined length, subjecting it to annealing treatment, forming a lubricating film layer such as zinc phosphate on the surface, and then forging. Produced. Since the description of this part is the same, description of this part is abbreviate | omitted in the following Example 8-10.

  As shown in FIGS. 8A to 8D, a round bar-shaped material is forged to form a substantially rectangular shape that is symmetrical in the vertical and horizontal directions when viewed from both the left and right sides. As shown in FIGS. 8 (A) and 8 (C), a connecting cylinder portion 41 protruding in an arc shape is formed from the central portion in the axial direction (left-right direction) to the left end portion.

  Moreover, after forging a hole in the vertical and horizontal center portions in FIG. 8A, the female serration 45 is cut out and processed in the next cutting step. Furthermore, as shown in FIG. 8 (A), the first concave portion 51 having a substantially V shape and the second end are formed from the central portion in the axial direction (left / right direction) in FIG. 8 (B) to the left end portion. A pair of recesses 52 are formed by forging so that the vertical direction and the horizontal direction are symmetrical as seen in FIG.

  The upper substantially V-shaped first recess 51 is V-shaped so that the width in the left-right direction in FIG. 8A gradually decreases from the upper end surface of the coupling cylinder portion 41 toward the female serration 45. The tip of the V-shape is formed so as not to penetrate the female serration 45.

  Further, the lower substantially V-shaped second recess 52 is formed so that the width in the left-right direction in FIG. 8A gradually narrows from the lower end surface of the coupling tube portion 41 toward the female serration 45. The tip of the V-shape is formed so as not to penetrate the female serration 45.

  A first slit 431 that extends in the vertical direction of FIG. 8A and penetrates the female serration 45 is formed in the first recess 51 by cutting. Similarly, a second slit 432 extending in the vertical direction of FIG. 8A and penetrating through the female serration 45 is formed in the second recess 52 by cutting. The gaps δ1 and δ2 of the first cut 431 and the second cut 432 are formed with the same dimensions.

  A first flange portion 46 including a left flange portion 461 and a right flange portion 462 is formed integrally with the coupling cylinder portion 41 with the first slit 431 interposed therebetween. In addition, a second flange portion 47 including a left flange portion 471 and a right flange portion 472 is formed integrally with the coupling cylinder portion 41 with the second slit 432 interposed therebetween.

  A first screw hole 481 is formed by cutting in the right flange portion 462 of the first flange portion 46 in a direction perpendicular to the flange surface (the left-right direction in FIG. 8A). In addition, the right flange portion 472 of the second flange portion 47 has a female serration 45 sandwiched in a direction perpendicular to the flange surface (left and right direction in FIG. 8A) with respect to the first screw hole 481. The second screw hole 482 is formed by cutting at a symmetrical position.

  A first through hole 491 is formed by cutting in the left flange portion 461 of the first flange portion 46 concentrically with the first screw hole 481. A second through hole 492 is formed in the left flange portion 471 of the second flange portion 47 concentrically with the second screw hole 482 by cutting. Therefore, if the bolts 8 and 8 (see FIG. 2) are inserted into the first through hole 491 and the second through hole 492, respectively, and the bolts 8 and 8 are rotated, the first screw hole 481 and the second screw hole 481 Bolts 8 and 8 are screwed into the screw holes 482.

  When the bolts 8 and 8 are screwed into the first screw hole 481 and the second screw hole 482, the first flange portion 46 and the second flange portion 47 are tightened, and the first slit 431 and the second The gaps δ1 and δ2 of the cut 432 are uniformly narrowed, the inner diameter of the female serration 45 is reduced, and the outer periphery of the shaft 7 (see FIG. 2) is strongly tightened.

  Next, the right side of the central portion in the axial direction (left-right direction) in FIG. 8B is formed by forging into a bifurcated shape, and the arm portions 42 are formed. A female serration 45 passes through the bottom 53 near the connecting cylinder 41 at the left end of the arms 42 and 42 and is processed into a through hole. The first slit 431, the second slit 432, the first recess 51, and the second recess 52 are processed into a shape that does not penetrate the bottom 53 of the arm portions 42 and 42.

  Next, as shown in FIG. 8D, the right end surfaces 421 and 421 of the arm portions 42 and 42 are formed by punching into an arc shape by shaving. When the arm portions 42, 42 are forged into two forks, when the right end surfaces 421, 421 of the arm portions 42, 42 are simultaneously formed into an arc shape, shaving may be unnecessary. As in the first embodiment, a pair of circular holes 50 (bearing holes) are formed in the arm portions 42 and 42 by cutting and a bearing for fitting with the cross shaft 6 is inserted.

  In the universal joint of Example 7 of the present invention, a pair of substantially V-shaped recesses are formed symmetrically, so that the mold can be simplified and simplified, so the load applied to the mold is reduced. Mold life is extended.

  Moreover, since the cut is formed by cutting in the portion where the substantially V-shaped concave portion is formed by forging, the volume to be removed by cutting can be reduced, so the time for cutting the cut is shortened, and the cutting tool The service life is also extended, and the processing cost can be reduced.

  Next, an eighth embodiment of the present invention will be described. FIGS. 9A and 9B are component diagrams showing a universal joint yoke according to an eighth embodiment of the present invention, in which FIG. 9A is a sectional view taken along line GG in FIG. 9B, FIG. 9B is a front view, and FIG. (D) is a bottom view of (B). In the following description, only structural portions and operations different from the above embodiment will be described, and redundant description will be omitted. Further, the same parts will be described with the same numbers.

  The eighth embodiment is a modification of the seventh embodiment, in which the coupling cylinder portion 41 is formed in an arcuate recess and is formed in a shape that is recessed from the first flange portion 46 and the second flange portion 47. It is. Since the manufacturing process of the yoke 4 of the eighth embodiment is the same as the manufacturing process of the yoke 4 of the seventh embodiment, detailed description thereof is omitted.

  Next, a ninth embodiment of the present invention will be described. FIGS. 10A and 10B are component diagrams showing a universal joint yoke according to a ninth embodiment of the present invention. FIG. 10A is a cross-sectional view taken along the line H-H in FIG. 10B, FIG. 10B is a front view, and FIG. (D) is a bottom view of (B). In the following description, only structural portions and operations different from the above embodiment will be described, and redundant description will be omitted. Further, the same parts will be described with the same numbers.

  The ninth embodiment is a modification of the seventh embodiment, in which the female serration 45 is a blind hole. As shown in FIGS. 10 (A) to 10 (D), the connecting cylinder portion 41 is forged at the center in the vertical direction and the horizontal direction in FIG. It cuts out in the cutting process.

  The female serration 45 does not penetrate through the bottom 53 near the connecting cylinder 41 at the left end of the arm 42, 42, and is processed into a blind hole. The first slit 431, the second slit 432, the first recess 51, and the second recess 52 are processed into a shape that does not penetrate the bottom 53 of the arm portions 42 and 42. Since the manufacturing process of the yoke 4 of the ninth embodiment is the same as the manufacturing process of the yoke 4 of the seventh embodiment, detailed description thereof is omitted.

  In the universal joint of the ninth embodiment of the present invention, since the female serration 45 is formed in the blind hole, the coupling cylinder portion 41 has high rigidity and can transmit a large rotational torque.

  Next, a tenth embodiment of the present invention will be described. FIG. 11 is a component diagram showing a universal joint yoke according to a tenth embodiment of the present invention, in which (A) is a sectional view taken along line JJ of (B), (B) is a front view, and (C) is (B). (D) is a bottom view of (B), (E) is a front view of a bolt. In the following description, only structural portions and operations different from the above embodiment will be described, and redundant description will be omitted. Further, the same parts will be described with the same numbers.

  The tenth embodiment is a modification of the seventh embodiment, in which one of the bolts for tightening the flange portion is a stepped bolt, and the tightening force with which the bolt tightens the flange portion is regulated to a predetermined value, and the yoke 4 and the shaft 7 are This is an example in which the workability is the same as that of a conventional yoke in which only one bolt is fastened to the flange portion.

  As shown in FIGS. 11 (A) to 11 (D), the coupling cylinder portion 41 does not have the first V-shaped first recess 51 and the second recess 52 and passes through the female serration 45. 431 and the second slit 432 are formed by cutting. The gaps δ1 and δ2 of the first cut 431 and the second cut 432 are formed with the same dimensions.

  A first flange portion 46 including a left flange portion 461 and a right flange portion 462 is formed integrally with the coupling cylinder portion 41 with the first slit 431 interposed therebetween. In addition, a second flange portion 47 including a left flange portion 471 and a right flange portion 472 is formed integrally with the coupling cylinder portion 41 with the second slit 432 interposed therebetween.

  In the right flange portion 462 of the first flange portion 46, a first screw hole 481 is formed by cutting in a direction perpendicular to the flange surface (the left-right direction in FIG. 11A). Further, the right flange portion 472 of the second flange portion 47 has a female serration 45 sandwiched in a direction perpendicular to the flange surface (left and right direction in FIG. 11A) with respect to the first screw hole 481. The second screw hole 482 is formed by cutting at a symmetrical position.

  A first through hole 491 having a diameter larger than the diameter of the valley of the first screw hole 481 is formed in the left flange portion 461 of the first flange portion 46 concentrically with the first screw hole 481. It is formed with. The first through hole 491 is formed away from the axial center of the female serration 45 toward the radially outer end side (above FIG. 11A) so as not to be caught by the female serration 45. A second through hole 492 is formed by cutting in the left flange portion 471 of the second flange portion 47 so as to be concentric with the second screw hole 482.

  As shown in FIG. 11E, the bolt 9 to be screwed into the first screw hole 481 is formed with a large-diameter shaft portion 92 larger in diameter than the outer diameter of the male screw portion 91. A stepped portion 93 is formed at a connecting portion between the shaft portion 92 and the male screw portion 91 to form a stepped bolt. The outer diameter dimension of the large diameter shaft portion 92 is formed slightly smaller than the inner diameter dimension of the first through hole 491. As a method for forming the stepped portion 93, a hollow cylindrical collar having the same outer diameter as that of the large-diameter shaft portion 92 may be fitted on the outer periphery of a normal bolt.

  Before assembling the yoke 4 of the tenth embodiment to the shaft 7 (see FIGS. 3B and 3C), the bolt 9 is inserted into the first through hole 491 in advance, and the bolt 9 is rotated to The bolt 9 is screwed into the screw hole 481. When the first flange portion 46 is tightened and the gap δ1 of the first slit 431 is narrowed, the stepped portion 93 comes into contact with the right flange portion 462 of the first flange portion 46, and the bolt 9 is further tightened. It is regulated so that it cannot be done.

  Since the large-diameter shaft portion 92 of the bolt 9 is not caught by the male serration 71 (see FIGS. 3B and 3C) of the shaft 7, the yoke 4 can be used even after the bolt 9 is fastened to the first flange portion 46. It is possible to attach the shaft 7 to the shaft.

  Therefore, after assembling the shaft 7 to the yoke 4 to which the bolt 9 is tightened, the bolt 8 (see FIG. 2) is screwed into the second screw hole 482. Then, the second flange portion 47 is tightened, the gap δ2 of the second slit 432 is narrowed, the inner diameter of the female serration 45 is reduced, and the outer periphery of the shaft 7 is strongly tightened.

  When the bolt 8 is screwed into the second screw hole 482, the male serration 71 of the shaft 7 is serrated and engaged with the female serration 45 of the coupling tube portion 41, so that rotational torque can be transmitted. Further, the outer periphery of the bolt 8 is engaged with the annular groove 72 (see FIGS. 3B and 3C) of the shaft 7, so that the shaft 7 does not come out of the female serration 45.

  In the universal joint according to the tenth embodiment of the present invention, the first flange portion 46 and the second flange portion 47 are fastened by using two bolts 8 and 9, so that the coupling tube portion 41 of the shaft 7 and the yoke 4 is used. And the coupling rigidity can be increased. In addition, since the work of assembling the yoke 4 and the shaft 7 with the vehicle body is only the work of tightening one bolt 8, the workability is the same as that of a conventional yoke that tightens only one bolt to the flange portion.

  As shown in the seventh to tenth embodiments, the coupling cylinder portion 41 may have a convex shape, a concave shape, or a planar shape, and the shape can be various shapes such as a circle, an ellipse, and a rectangle.

  In the above-described embodiment, an example in which a substantially V-shaped concave portion is formed as the concave portion has been described. However, a concave portion having a substantially U-shape, rectangular shape, circular shape, elliptical shape, or the like may be used. Moreover, although the example which formed the female serration or two planes in the connection cylinder part was demonstrated in the said Example, hole parts, such as a female spline, a polygonal hole, and an elliptical hole, may be sufficient. Further, in the above embodiment, the gaps δ1 and δ2 of the first cut 431 and the second cut 432 are formed to have the same dimensions, but may be different.

BRIEF DESCRIPTION OF THE DRAWINGS It is the side view which showed the whole steering apparatus provided with the coupling of this invention, and was cut in part, Comprising: The Example applied to the electric power steering apparatus which has a steering assistance part is shown. The universal joint of Example 1 of this invention is shown, (A) is AA sectional drawing of (B), (B) is a front view of a universal joint. (A) is sectional drawing which shows the state which removed the volt | bolt and the axis | shaft from FIG. 2 (A), (B) is a front view which shows the axis | shaft of FIG. 2, (C) is BB sectional drawing of (B). is there. FIG. 3A is a view corresponding to FIG. 3A showing the universal joint of the second embodiment of the present invention, and FIG. 3B is a view corresponding to FIG. 3A showing the universal joint of the third embodiment of the present invention. The universal joint of Example 4 of this invention is shown, (A) is FIG. 2 (A) equivalent view, (B) is a front view which shows the axis | shaft of (A), (C) is CC cross section of (B). FIG. FIG. 3A is a view corresponding to FIG. 3A showing a universal joint of Embodiment 5 of the present invention, FIG. 3B is a front view showing a shaft fitted to FIG. 3A, and FIG. It is -D sectional drawing. The universal joint of Example 6 of this invention is shown, (A) is EE sectional drawing of (B), (B) is a front view of a universal joint. It is component drawing which shows the yoke of the universal joint of Example 7 of this invention, Comprising: (A) is FF sectional drawing of (B), (B) is a front view, (C) is the right side surface of (B). FIG. 4D is a bottom view of FIG. It is component drawing which shows the yoke of the universal joint of Example 8 of this invention, Comprising: (A) is GG sectional drawing of (B), (B) is a front view, (C) is a right view of (B). FIG. 4D is a bottom view of FIG. It is component drawing which shows the yoke of the universal joint of Example 9 of this invention, Comprising: (A) is HH sectional drawing of (B), (B) is a front view, (C) is the right side surface of (B). FIG. 4D is a bottom view of FIG. It is component drawing which shows the yoke of the universal joint of Example 10 of this invention, Comprising: (A) is JJ sectional drawing of (B), (B) is a front view, (C) is a right view of (B). The figure, (D) is a bottom view of (B), and (E) is a front view of the bolt.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Steering wheel 12 Steering shaft 12A Female steering shaft 12B Male steering shaft 13 Steering column 13A Outer column 13B Inner column 14 Support bracket 15 Universal joint 16 Intermediate shaft 16A Male intermediate shaft 16B Female intermediate shaft 17 Universal joint 18 Car body 20 Assist device 21 Gear Housing 23 Output shaft 26 Electric motor 261 Case 30 Steering gear 31 Input shaft 32 Tie rod 4 Yoke 41 Coupling tube portion 42 Arm portion 421 Right end surface 431 First slit 432 Second slit 45 Female serration 451 Plane 46 First flange portion 461 Left flange portion 461A Rectangular protrusion 462 Right flange portion 462A Rectangular protrusion 47 Second flange portion 471 Left flange Portion 471A Rectangular protrusion 472 Right flange 472A Rectangular protrusion 481 First screw hole 482 Second screw hole 491 First through hole 492 Second through hole 493 Third through hole 494 Fourth through hole 50 Circular hole (Bearing hole)
51 First recess 52 Second recess 53 Bottom 6 Cross shaft 7 Axis 71 Male serration 72 Annular groove 73 Groove 74 Plane 8 Bolt 81 Nut 9 Bolt 91 Male screw portion 92 Large diameter shaft portion 93 Step portion

Claims (17)

A coupling cylinder portion having a hole portion for fitting the shaft to the proximal end portion so that rotational torque can be transmitted,
A first slit and a second slit which are formed in the coupling cylinder portion with the hole portion interposed therebetween, and penetrate the hole portion;
A first flange portion provided integrally with the coupling cylinder portion with the first slit interposed therebetween, and configured by a pair of left and right flange portions;
A second flange portion, which is provided integrally with the coupling cylinder portion across the second slit, and is composed of a pair of left and right flange portions;
A first through hole formed in one of the left and right flange portions of the first flange portion;
A second through hole formed in either the left or right flange portion of the second flange portion;
A first screw hole formed concentrically with the first through hole for screwing a bolt inserted from the first through hole into the left or right flange portion of the first flange portion. ,
A second screw hole formed concentrically with the second through hole for screwing a bolt inserted from the second through hole into the left or right flange portion of the second flange portion. A joint characterized by comprising: The joint according to claim 1,
The first through hole and the second through hole are formed at symmetrical positions with the hole interposed therebetween, respectively. A coupling cylinder portion having a hole portion for fitting the shaft to the proximal end portion so that rotational torque can be transmitted,
A first slit and a second slit which are formed in the coupling cylinder portion with the hole portion interposed therebetween, and penetrate the hole portion;
A first flange portion provided integrally with the coupling cylinder portion with the first slit interposed therebetween, and configured by a pair of left and right flange portions;
A second flange portion, which is provided integrally with the coupling cylinder portion across the second slit, and is composed of a pair of left and right flange portions;
A first through hole formed in one of the left and right flange portions of the first flange portion;
A second through hole formed in either the left or right flange portion of the second flange portion;
A third through-hole formed concentrically with the first through-hole in order to insert the bolt inserted through the first through-hole into the left or right flange portion of the first flange portion;
A fourth through hole formed concentrically with the second through hole in order to insert a bolt inserted from the second through hole into the left or right flange part of the second flange part;
A joint comprising nuts that are screwed into the bolts and fasten the bolts to the first flange portion and the second flange portion, respectively. In the joint according to claim 3,
The first through hole and the second through hole are formed at symmetrical positions with the hole interposed therebetween, respectively. In the joint according to any one of claims 1 to 4,
In the coupling cylinder portion, a first recess and a second recess that do not penetrate the hole are respectively formed at symmetrical positions across the hole.
The first slit is formed in the first recess;
The joint, wherein the second slit is formed in the second recess. The joint according to claim 5,
The joint, wherein the first recess and the second recess are substantially V-shaped recesses. In the joint according to any one of claims 1 to 4,
A female serration that engages with the male serration of the shaft and transmits rotational torque is formed in the hole. In the joint according to any one of claims 1 to 4,
The joint is characterized in that the hole is formed with two planes for transmitting rotational torque by engaging with the two planes of the shaft. In the joint according to any one of claims 1 to 4,
The joint is characterized in that a groove for engaging with the bolt is formed on the shaft. The joint according to claim 9,
The joint is characterized in that the bolt is engaged with the groove of the shaft when the bolt passes through the hole of the coupling cylinder portion. In the joint according to any one of claims 1 to 4,
At least one of the bolts is a stepped bolt in which a step portion is formed. In the joint according to any one of claims 1 to 4,
A joint characterized in that a gap smaller than the gap between the first and second slits is formed at the radially outer ends of the first and second slits. In the joint according to any one of claims 1 to 4,
The coupling cylinder portion is integrally formed with a pair of arm portions having bearing holes for supporting the cross shaft on the opposite side to the hole portion. The joint according to claim 13,
The said hole is formed in the blind hole which does not penetrate the bottom part of the said arm part, The coupling characterized by the above-mentioned. The joint according to claim 13,
The joint according to claim 1, wherein the first slit and the second slit are formed in a shape that does not penetrate the bottom of the arm portion. In the joint according to any one of claims 1 to 4,
The joint is a universal joint that connects the intermediate shaft and the steering shaft, or the intermediate shaft and the steering gear.
A joint characterized in that an assist device for applying a steering assist force to the steering shaft is provided between the intermediate shaft and the steering wheel. The joint according to any one of claims 1 to 4, wherein the joint is formed by forging.

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