JP2012140980A - Rolling bearing fixing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rolling bearing fixing device preventing the occurrence of rotation failure such as increasing of torque.SOLUTION: A rolling bearing 20A rotatably supports a rotating shaft 1 with an inner ring 21A fixed by a nut 22 to the rotating shaft 1 around which a belt of a belt type continuously variable transmission is wound. The groove bottom diameter d1 of a raceway groove 30 of the inner ring 21A is set larger than the outer diameter d2 of a contact part 40A of the inner ring 21A with the nut 22, and the groove bottom diameter d1 of the raceway groove 30 of the inner ring 21A is set larger than the outer diameter d3 of a contact part 41A in the inner ring 21A with a cover 14.

Description

  The present invention relates to a rolling bearing fixing device, and more particularly to a rolling bearing fixing device that fixes a rolling bearing used in a belt type continuously variable transmission or the like.

  The belt type continuously variable transmission (CVT) is configured such that a belt is passed between V-grooves of a driving pulley provided on an input shaft and a driven pulley provided on an output shaft, and V-grooves of a driving side and a driven pulley are provided. The gear ratio is changed steplessly by changing the width (for example, see Patent Document 1).

  FIG. 5 shows the configuration of the input side of a belt type continuously variable transmission as an example. Around the input shaft 1, a fixed pulley portion 2 is provided that cannot move in the axial direction and cannot rotate relative to the input shaft 1, and the movable pulley portion 3 can move in the axial direction relative to the input shaft 1 and can rotate relatively. A drive pulley 4 that is impossible is configured. Then, a belt 7 is hung on a V groove 6 formed by the fixed pulley portion 2 and the movable pulley portion 3, and the belt 7 is hung on a driven pulley on the output shaft side (not shown).

  Further, a cylinder device 8 for moving the movable pulley portion 3 in the axial direction is provided around the input shaft 1 on the opposite side of the movable pulley portion 3 from the fixed pulley portion 2. The cylinder device 8 includes a substantially cylindrical outer peripheral wall 10 projecting from the outer peripheral portion of the movable pulley portion 3 to the opposite side of the fixed pulley portion 2, and a stepped cylindrical portion 11 having one end fixed to the input shaft 1. And a flange portion 12 extending from the other end portion of the stepped cylindrical portion 11 to the outer peripheral side, and an outer peripheral edge portion of the flange portion 12 is slidably fitted inside the outer peripheral wall 10. A member 13, a substantially bottomed cylindrical cover 14 having an inner peripheral surface facing the outer peripheral surface of the cylindrical portion 11 of the first piston member 13 and fixed to the input shaft 1, and fixed to the distal end portion of the outer peripheral wall 10 And an annular second piston member 15 slidably fitted to the outer peripheral surface of the cylindrical portion 11 of the first piston member 13 and the inner peripheral surface of the cover 14. The cylinder device 8 is configured to move the movable pulley by the liquid pressure introduced into the liquid chamber 17 surrounded by the movable pulley portion 3 and the first piston member 13 and the liquid chamber 18 surrounded by the second piston member 15 and the cover 14. The part 3 is moved in the axial direction.

  The input shaft 1 is rotatably supported by a large rolling bearing 19 arranged on the fixed pulley portion 2 side and a small rolling bearing 20 arranged on the movable pulley portion 3 side. The inner ring 21 of the side rolling bearing 20 is fastened to the input shaft 1 by a nut 22 together with the cover 14 of the cylinder device 8 and the first piston member 13. That is, the first piston member 13 is brought into contact with the step portion 23 formed on the input shaft 1, and the first piston member 13, the cover 14, and the inner ring 21 of the rolling bearing 20 are fitted to the input shaft 1 in this order, By screwing the nut 22 into the male screw portion 24 of the input shaft 1, the first piston member 13, the cover 14, and the inner ring 21 of the rolling bearing 20 are clamped between the step portion 23 and the nut 22 in the axial direction.

Japanese Patent Laid-Open No. 2-154850

  By the way, in the rolling bearing 20 that supports the movable pulley 3 side of the input shaft 1 described above, the inner ring 21 is fastened to the input shaft 1 together with the cover 14 and the first piston member 13 of the cylinder device 8 by the nut 22 as described above. In this case, it is necessary to fasten and fix the nut 22 with a large axial force so as to overcome the operating pressure introduced into the cylinder device 8.

  In addition, the rolling bearing 20 that supports the movable pulley portion 3 side of the input shaft 1 is farther from the belt 7 than the rolling bearing 19 on the fixed pulley portion 2 side, so that it is smaller than the rolling bearing 19 due to bearing load. The size is used. For this reason, when the groove diameter of the raceway groove that guides the rolling element is smaller than the outer diameter of the portion that contacts the nut 22 in the inner ring 21 and a large axial force is introduced when the nut 22 is fastened, the rolling element is guided. There was a possibility that the raceway groove to be deformed would cause rotation failure such as a negative gap and increased torque. Such a problem is more likely to occur in the rolling bearing 20 on the movable pulley portion 3 side, but may also occur in the rolling bearing 19 on the fixed pulley portion 2 side, and the output in the belt type continuously variable transmission is also possible. There is a possibility that it may also occur in the shaft.

  The present invention has been made to eliminate such inconveniences, and an object of the present invention is to provide a rolling bearing fixing device capable of preventing the occurrence of rotation failure such as an increase in torque in the rolling bearing. is there.

The above object of the present invention can be achieved by the following constitution.
(1) An inner ring having an inner ring raceway on an outer peripheral surface, an outer ring having an outer ring raceway on an inner peripheral surface, a plurality of rolling elements arranged to be freely rollable between the inner ring raceway and the outer ring raceway, A rolling bearing having a cage that holds the rolling elements at a predetermined interval in the circumferential direction;
A rotating shaft having a fitting surface with which the inner ring is fitted, and a male screw portion provided adjacent to the fitting surface;
A positioning member that abuts one axial end of the inner ring and determines the axial position of the inner ring;
A nut that is screwed into the male thread portion of the rotating shaft and fixed by clamping the inner ring together with the positioning member;
A rolling bearing fixing device comprising:
A groove bottom diameter of the inner ring raceway is larger than an outer diameter of a contact part between the inner ring and the positioning member, and larger than an outer diameter of a contact part between the inner ring and the nut. Rolling bearing fixing device.
(2) A contact surface having a smaller diameter than the groove bottom diameter of the inner ring raceway is provided on the axial end surface of the inner ring,
The rolling bearing fixing device according to (1), wherein an axial end surface other than the contact portion is recessed inward in the axial direction with respect to the contact surface.
(3) The rolling bearing fixing device according to (2), wherein an annular step portion is provided on an outer diameter side at both axial ends of the inner ring.
(4) On the axial end surface of the positioning member facing the rolling bearing, there is an abutting surface that abuts the inner ring by protruding an inner diameter side portion smaller in diameter than the groove bottom diameter of the inner ring raceway in the axial direction. The rolling bearing fixing device according to (1), which is provided.
(5) An abutment surface that abuts the inner ring by protruding an inner diameter side portion smaller in diameter than the groove bottom diameter of the inner ring raceway in the axial direction is provided on the axial end surface of the nut facing the rolling bearing. The rolling bearing fixing device according to (1) or (4), wherein

  According to the rolling bearing fixing device of the present invention, the groove bottom diameter of the inner ring raceway is larger than the outer diameter of the contact part between the inner ring and the positioning member, and is larger than the outer diameter of the contact part between the inner ring and the nut. Therefore, even if a large axial force is introduced at the time of fastening the nut, it is possible to prevent deformation in the raceway groove that guides the rolling element in the inner ring. Therefore, it is possible to prevent a rotation failure such as an increase in torque due to the negative gap between the raceway groove of the inner ring and the rolling element.

It is principal part sectional drawing for demonstrating 1st Embodiment of the rolling bearing fixing device which concerns on this invention. It is principal part sectional drawing for demonstrating 2nd Embodiment of the rolling bearing fixing device which concerns on this invention. It is principal part sectional drawing for demonstrating 3rd Embodiment of the rolling bearing fixing device which concerns on this invention. It is principal part sectional drawing for demonstrating 4th Embodiment of the rolling bearing fixing device which concerns on this invention. It is sectional drawing of the input shaft of a belt type continuously variable transmission.

  Embodiments of a rolling bearing fixing device according to the present invention will be described below in detail with reference to the drawings. In addition, since structures other than the main part of the present invention are the same as those of the prior art, the same parts are denoted by the same reference numerals, and description thereof is omitted or simplified.

(First embodiment)
First, a first embodiment of a rolling bearing fixing device according to the present invention will be described with reference to FIG. As shown in FIG. 1, in the rolling bearing fixing device according to the first embodiment, the rolling bearing 20 </ b> A is provided on the movable pulley portion 3 side of the input shaft 1 that is the rotating shaft of a belt type continuously variable transmission (CVT), specifically. Is disposed on the opposite side of the movable pulley portion 3 from the fixed pulley portion 2 and rotatably supports the input shaft 1.

  As shown in FIG. 1, the rolling bearing 20 </ b> A includes an inner ring 21 </ b> A having an inner ring raceway groove 30 having an arc-shaped cross section on an outer peripheral surface, an outer ring 31 having an outer ring raceway groove 32 having an arc-shaped cross section on an inner peripheral surface, and an inner ring raceway groove. 30 and a plurality of balls (rolling elements) 33 that are rotatably arranged between the outer ring raceway grooves 32 and a cage 34 that holds the plurality of balls 33 at a predetermined interval in the circumferential direction.

  In this rolling bearing 20A, the inner ring 21A is fitted on the fitting surface of the input shaft 1, and at this time, one end surface 35A abuts against the abutting surface 36 of the cover (positioning member) 14 of the cylinder device 8 in the axial direction. The other end surface 37A abuts in the axial direction on the abutment surface 38 of the nut 22 screwed into the male screw portion 24 adjacent to the fitting surface of the input shaft 1. The rolling bearing 20 </ b> A is fixed to the input shaft 1 by tightening the nut 22.

  Here, in the rolling bearing 20A, the diameter difference between the groove bottom diameter d1 and the inner diameter of the raceway groove 30 of the inner ring 21A is increased, and the radial thickness is increased. Thereby, the groove bottom diameter d1 of the raceway groove 30 of the inner ring 21A is such that the contact portion 40A that contacts the contact portion between the inner ring 21A and the nut 22, that is, the contact surface 38 of the nut 22 at the other end surface 37A of the inner ring 21A. It is set larger than the outer diameter d2.

  Further, the groove bottom diameter d1 of the raceway groove 30 of the inner ring 21A is outside the contact portion 41A that contacts the contact portion between the inner ring 21A and the cover 14, that is, the contact surface 36 of the cover 14 at the one end surface 35A of the inner ring 21A. It is set to be larger than the diameter d3.

  In the rolling bearing fixing device configured as described above, the groove bottom diameter d1 of the raceway groove 30 of the inner ring 21A is larger than the outer diameter d3 of the contact portion 41A with the cover 14 in the inner ring 21A, and the nut in the inner ring 21A. Therefore, even if a large axial force is introduced when the nut 22 is fastened, deformation that occurs in the raceway groove 30 of the inner ring 21A can be prevented. Therefore, it is possible to prevent a rotation failure such as an increase in torque due to the negative gap between the raceway groove 30 and the ball 33 of the inner ring 21A.

(Second Embodiment)
Next, a second embodiment of the rolling bearing fixing device according to the present invention will be described with reference to FIG. In the rolling bearing fixing device of the second embodiment, the outer peripheral side is partially cut out at both axial ends of the inner ring 21B of the rolling bearing 20B, and an annular stepped portion 44 that forms a gap that does not contact the nut 22 is formed. And annular stepped portions 45 that form gaps that do not come into contact with the cover 14 are formed.

  As a result, the other end surface 37B of the inner ring 21B becomes a contact portion 40B that contacts the contact surface 38 of the nut 22 in the axial direction, and the bottom diameter d1 of the raceway groove 30 of the inner ring 21B is larger than the outer diameter d2 of the contact portion 40B. It is set large. Further, the one end surface 35B of the inner ring 21B serves as a contact portion 41B that contacts the contact surface 36 of the cover 14 in the axial direction, and the bottom diameter d1 of the raceway groove 30 of the inner ring 21B is larger than the outer diameter d3 of the contact portion 41B. Is set.

  That is, a contact portion (contact surface) 40B and a contact portion (contact surface) 41B having a diameter smaller than the groove bottom diameter d1 of the raceway groove 30 are provided on both end surfaces in the axial direction of the inner ring 21B. The end surfaces in the axial direction other than 41B are recessed more inward in the axial direction than the contact portions 40B and 41B.

  Also with the rolling bearing fixing device configured as described above, the groove bottom diameter d1 of the raceway groove 30 of the inner ring 21B is larger than the outer diameter d3 of the contact portion 41B with the cover 14 in the inner ring 21B, and in the inner ring 21B. Since it is larger than the outer diameter d2 of the contact portion 40B with the nut 22, even if a large axial force is introduced when the nut 22 is fastened, deformation that occurs in the raceway groove 30 of the inner ring 21B can be prevented. Therefore, it is possible to prevent a rotation failure such as an increase in torque due to the negative gap between the raceway groove 30 and the ball 33 of the inner ring 21B.

  In addition, by changing the shape of the inner ring 21B, even if the nut 22 and the cover 14 having the same dimensions as those of the first embodiment are used, the bottom diameter d1 of the raceway groove 30 of the inner ring 21B is changed to the nut 22 and the cover of the inner ring 21B. 14 can be larger than the outer diameters d2 and d3 of the contact portions 40B and 41B, and the outer diameter of the bearing can be made smaller than that of the first embodiment.

(Third embodiment)
Next, a third embodiment of the rolling bearing fixing device according to the present invention will be described with reference to FIG. In the rolling bearing fixing device of the third embodiment, the outer peripheral side is partially cut off on the contact surface 38C side of the nut 22C and the contact surface 36C side of the cover 14, and the inner ring 21C of the rolling bearing 20C is not cut. An annular stepped portion 47 that forms a gap that does not contact the other end surface 37C and an annular stepped portion 48 that forms a gap that does not contact the one end surface 35C of the inner ring 21C are formed.

  Thereby, the groove bottom diameter d1 of the raceway groove 30 of the inner ring 21C is set larger than the outer diameter d2 of the contact portion 40C that contacts the contact surface 38C of the nut 22C on the other end surface 37C of the inner ring 21C. Further, the groove bottom diameter d1 of the raceway groove 30 of the inner ring 21C is set larger than the outer diameter d3 of the contact portion 41C that contacts the contact surface 36C of the cover 14 at the one end face 35C of the inner ring 21C.

  That is, on the axial end surface of the cover (positioning member) 14 facing the rolling bearing 20C, an inner diameter side portion smaller than the groove bottom diameter d1 of the inner ring raceway 30 protrudes in the axial direction so as to contact the inner ring 21C. A contact surface 36C is provided. Further, on the axial end surface of the nut 22C facing the rolling bearing 20C, an abutting surface 38C that abuts the inner ring 21C by projecting an inner diameter side portion smaller in diameter than the groove bottom diameter d1 of the inner ring raceway groove 30 in the axial direction. Is provided.

  Also with the rolling bearing fixing device configured as described above, the groove bottom diameter d1 of the raceway groove 30 of the inner ring 21 is larger than the outer diameter d3 of the contact portion 41C with the cover 14 in the inner ring 21C, and in the inner ring 21C. Since it is larger than the outer diameter d2 of the contact portion with the nut 22C, even if a large axial force is introduced when the nut 22 is fastened, deformation that occurs in the raceway groove 30 of the inner ring 21C can be prevented. Accordingly, it is possible to prevent a rotation failure such as an increase in torque due to the negative gap between the raceway groove 30 and the ball 33 of the inner ring 21C.

  In addition, the bottom diameter d1 of the raceway groove 30 of the inner ring 21B can be made larger by changing the shape of the nut 22 and the cover 14 than the outer diameters d2 and d3 of the contact portions 40C and 41C of the inner ring 21C with the nut 22C and the cover 14. As in the second embodiment, the outer diameter of the bearing can be made smaller than in the first embodiment.

(Fourth embodiment)
Next, a fourth embodiment of the rolling bearing fixing device according to the present invention will be described with reference to FIG. In the rolling bearing fixing device of the fourth embodiment, as in the first embodiment, the diameter difference between the groove bottom diameter d1 and the inner diameter of the raceway groove 30 of the inner ring 21D of the rolling bearing 20D is increased, and the radial thickness is increased. Make it thicker. Thereby, the bottom diameter d1 of the raceway groove 30 of the inner ring 21D is set larger than the outer diameter d2 of the contact portion 40D that contacts the contact surface 38 of the nut 22 at the other end surface 37D of the inner ring 21D.

  Further, the groove bottom diameter d1 of the raceway groove 30 of the inner ring 21D is set larger than the outer diameter d3 of the contact portion 41D that contacts the contact surface 36 of the cover 14 at the one end face 35D of the inner ring 21D.

  In addition, the rolling bearing 20D of the fourth embodiment uses an increase in the thickness of the inner ring 21D described above, and the other end surface 37D of the inner ring 21D has an annular inner side so that the inner diameter side is recessed in the axial direction from the outer diameter side. A step portion 50 is formed. The outer diameter of the inner diameter step portion 50 is larger than the outermost diameter of the nut 22 so that the inner diameter step portion 50 includes the contact portion 40 </ b> D. Thereby, at the time of attachment to the input shaft 1, a part of the nut 22 enters the inner ring 21D side. The inner diameter step portion 50 has an inner diameter smaller than the groove bottom diameter d1 of the raceway groove 30 of the inner ring 21D.

  Also by the rolling bearing fixing device of the fourth embodiment configured as described above, the groove bottom diameter d1 of the raceway groove 30 of the inner ring 21D is larger than the outer diameter d3 of the contact portion 41D with the cover 14 in the inner ring 21D. And since it is larger than the outer diameter d2 of the contact part 40D with the nut 22 in the inner ring 21D, even if a large axial force is introduced when the nut 22 is fastened, the deformation generated in the raceway groove 30 of the inner ring 21D can be prevented. Therefore, it is possible to prevent a rotation failure such as an increase in torque due to the negative gap between the raceway groove 30 and the ball 33 of the inner ring 21D.

  In addition, since the inner step portion 50 is formed on the other end surface 37D of the inner ring 21D, a part of the nut 22 can be inserted into the inner ring 21D side in the axial direction, so that space saving in the axial direction can be achieved. it can.

In addition, this invention is not limited to each embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably.
In the rolling bearing fixing device of the first to fourth embodiments described above, the rolling bearing that supports the side opposite to the fixed pulley portion of the movable pulley portion of the input shaft of the belt type continuously variable transmission has been described as an example. The present invention is also applicable to a rolling bearing that supports the movable pulley portion side of the driven pulley on the output shaft of the type continuously variable transmission. Furthermore, the present invention may be applied to a rolling bearing that supports the fixed pulley portion side of the driving pulley on the input shaft and a rolling bearing that supports the fixed pulley portion side of the driven pulley on the output shaft.

Further, the rolling bearing fixing device of the present invention can be applied to structures other than the belt-type continuously variable transmission as long as the inner ring is sandwiched between a positioning member that determines the axial position of the inner ring and a nut. Therefore, the positioning member that determines the axial position of the inner ring is not limited to the cover of the present embodiment.
Furthermore, the rolling bearing applied to the present invention is not limited to the deep groove ball bearing of the above-described embodiment, but can also be applied to a cylindrical roller bearing or a tapered roller bearing in which an inner ring raceway groove is formed by a flange portion. is there.

1 Input shaft (rotary shaft)
2 fixed pulley section 3 movable pulley section 4 driving pulley 7 belt 14 cover (positioning member)
20A, 20B, 20C, 20D Rolling bearing 21A, 21B, 21C, 21D Inner ring 22, 22C Nut 40A, 40B, 40C, 40D Contact part 30 Track groove d1 Groove bottom diameter d2, d3 Outer diameter

Claims (5)

An inner ring having an inner ring raceway on an outer peripheral surface, an outer ring having an outer ring raceway on an inner peripheral surface, a plurality of rolling elements arranged to roll between the inner ring raceway and the outer ring raceway, and the plurality of rolling elements A rolling bearing having a cage that is held at predetermined intervals in the circumferential direction;
A rotating shaft having a fitting surface with which the inner ring is fitted, and a male screw portion provided adjacent to the fitting surface;
A positioning member that abuts one axial end of the inner ring and determines the axial position of the inner ring;
A nut that is screwed into the male thread portion of the rotating shaft and fixed by clamping the inner ring together with the positioning member;
A rolling bearing fixing device comprising:
A groove bottom diameter of the inner ring raceway is larger than an outer diameter of a contact part between the inner ring and the positioning member, and larger than an outer diameter of a contact part between the inner ring and the nut. Rolling bearing fixing device. A contact surface having a smaller diameter than the groove bottom diameter of the inner ring raceway is provided on the axial end surface of the inner ring,
The rolling bearing fixing device according to claim 1, wherein an end surface in the axial direction other than the contact portion is recessed inward in the axial direction from the contact surface.   The rolling bearing fixing device according to claim 2, wherein an annular step portion is provided on the outer diameter side at both axial end portions of the inner ring.   An abutting surface that abuts the inner ring is provided on an axial end surface of the positioning member facing the rolling bearing by protruding an inner diameter side portion smaller in diameter than the groove bottom diameter of the inner ring raceway in the axial direction. The rolling bearing fixing device according to claim 1.   An axial end surface of the nut facing the rolling bearing is provided with a contact surface that comes into contact with the inner ring by protruding an inner diameter side portion smaller in diameter than the groove bottom diameter of the inner ring raceway in the axial direction. The rolling bearing fixing device according to claim 1, wherein the rolling bearing fixing device is a rolling bearing fixing device.

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