JP2005172205A - Power transmission device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power transmission device, preventing each ball from moving inward in the radial direction of a driven side rotor in assembling and facilitating assembling work. <P>SOLUTION: This power transmission device includes a holding ring 16 holding each ball 14 outside in the radial direction of a hub 13 and allowing each ball 14 to move inward in the radial direction of the hub 13 when the power is shut-off, whereby in assembling, each ball 14 is prevented from moving inward in the radial direction of the hub 13. In this case, the holding ring 16 is broken by pressure contact of each ball 14 to allow the movement of each ball 14, so that a complicated structure for allowing the movement of each ball 14 is not needed to construct the holding ring 15 at a low cost. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a power transmission device used in, for example, a compressor of a vehicle air conditioner.

  Generally, as a compressor used in an air conditioner for a vehicle, a compressor body formed in a hollow shape, a compression unit that compresses fluid sucked into the compressor body, and a drive shaft connected to the compression unit And the drive shaft is rotated by the power of the engine to drive the compression section to suck and discharge the refrigerant.

Further, the power transmission device provided in the compressor includes a pulley to which power from the outside is transmitted, a transmission ring that is rotated by the power transmitted to the pulley, and a hub that is disposed on the inner peripheral surface side of the transmission ring. A plurality of balls that transmit the rotational force of the transmission ring to the hub, and a pressing ring that presses each ball in the axial direction toward the hub, and each ball pressed by the pressing ring is on the inner peripheral surface side of the transmission ring The torque of the transmission ring is transmitted to each ball by being locked to the ball, and when a torque of a predetermined magnitude or more is generated between the transmission ring and the hub, the ball to be locked to the transmission ring is pushed by the pressing ring. It is known that the power transmitted from the transmission ring to the hub is cut off by releasing the locking between the transmission ring and each ball by moving the hub inward in the radial direction of the hub against pressure. For example, see Patent Document 1.).
JP 2003-269489 A

  By the way, in the power transmission device, each ball is engaged with a plurality of grooves provided on one end face in the axial direction of the hub so as to be movable in the radial direction, and each ball is brought into the diameter of the hub by an inclined surface provided on the pressing ring. Although the pressure ring is arranged to face each groove of the hub in the axial direction, each ball has a diameter along the groove of the hub until the pressure ring is assembled at the time of assembly. It can be moved in any direction. For this reason, when the pressure ring is assembled, the ball easily moves inward in the radial direction, and if the ball is mistakenly moved inward in the radial direction, the power of the transmission ring is not transmitted to the ball. Therefore, it is necessary to perform assembly work carefully so that the balls do not move inward in the radial direction, and there is a problem that productivity is lowered.

  The present invention has been made in view of the above problems, and the object of the present invention is that each ball does not move inward in the radial direction of the driven-side rotating body during assembly, and the assembly work can be easily performed. It is in providing the power transmission device which can be performed.

  In order to achieve the above-mentioned object, the present invention provides an annular drive-side rotator that is rotated by external power, a driven-side rotator that is disposed on the inner peripheral surface side of the drive-side rotator, Provided with a plurality of balls for transmitting rotational force to the driven side rotating body and a pressing member for pressing each ball in the axial direction, and locking each ball pressed by the pressing member to the inner peripheral surface side of the driving side rotating body As a result, the rotational force of the drive-side rotator is transmitted to each ball, and when a torque of a predetermined magnitude or more is generated between the drive-side rotator and the driven-side rotator, By moving the ball against the pressing force of the pressing member inward in the radial direction of the driven-side rotator, the drive-side rotator and the balls are unlocked to change from the drive-side rotator to the driven-side rotator. In the power transmission device that cuts off the transmitted power, If the torque of a predetermined magnitude or more is generated between the driving side rotating body and the driven side rotating body, the inner side of the driven side rotating body A holding member that allows movement of the ball is provided.

  Thereby, each ball is held by the holding member on the radially outer side of the driven-side rotator, so that each ball does not move radially inward of the driven-side rotator during assembly. Further, when the balls move toward the radially inner side of the driven-side rotator when the power is cut off, the movement of the balls is not hindered because the movement of the balls is permitted by the holding member.

  According to the power transmission device of the present invention, each ball does not move inward in the radial direction of the driven-side rotator during assembly, so that assembly work can be easily performed and productivity can be improved. .

  1 to 7 show an embodiment of the present invention. FIG. 1 is a side sectional view of a power transmission device, FIG. 2 is a sectional view taken along line AA in FIG. 1, and FIG. 4 is a side cross-sectional view of the main part of the power transmission device, FIG. 5 is a front view of the main part of the holding ring showing the ball holding state, FIG. 6 is a side cross-sectional view of the main part showing the operation when the power is cut off, It is a principal part front view of the holding ring shown.

  This power transmission device is used in a compressor of a vehicle air conditioner, and transmits power to a drive shaft 2 protruding from one end of a compressor body 1.

  That is, the power transmission device according to the present embodiment generates the rotational force of the pulley 10 to which power from the outside is transmitted, the transmission ring 11 as a driving side rotating body that rotates by the power transmitted to the pulley 10, and the pulley 10. A plurality of shock absorbing rubbers 12 for transmitting to the transmission ring 11, a hub 13 as a driven side rotating body connected to the drive shaft 2, a plurality of balls 14 for transmitting the rotational force of the transmission ring 11 to the hub 13, and each ball A pressing ring 15 that presses 14 in the axial direction and a holding ring 16 that holds each ball on the radially outer side of the hub 13 are provided.

  The pulley 10 is configured such that a V belt (not shown) is wound around the outer peripheral surface, and is rotatably supported by the compressor main body 1 via a bearing 10 a disposed between the inner peripheral surface and the compressor main body 1. Has been. An annular groove 10b extending in the circumferential direction is provided on one end surface of the pulley 10, and a plurality of protrusions 10c protruding in the axial direction are provided in the groove 10b at intervals in the circumferential direction.

  The transmission ring 11 is disposed so that one end surface thereof faces the one end surface of the pulley 10, and a plurality of projecting portions 11 a projecting in the axial direction are provided on the surface facing the pulley 10 at intervals in the circumferential direction. . The protrusions 11a are inserted into the recesses 10b of the pulley 10 and are alternately disposed in the circumferential direction one by one with the protrusions 10c of the pulley 10, and are spaced apart from the protrusions 10c of the pulley 10 in the circumferential direction. And facing each other. A locking ring 11 b that locks each ball 14 from the outside in the radial direction is attached to the inner peripheral surface of the transmission ring 11. A plurality of tapered surfaces 11c that form a predetermined angle with each other are formed on the inner peripheral surface of the locking ring 11b, and each ball 14 is positioned on the radially outer side by contacting the adjacent tapered surfaces 11c. Yes.

  Each buffer rubber 12 is formed in a block shape, and is disposed between the protruding portion 10 c of the pulley 10 and the protruding portion 11 a of the transmission ring 11. Each buffer rubber 12 includes a pair of buffer portions 12a disposed on both sides in the circumferential direction of the protruding portion 10c of the pulley 10, and each buffer portion 12a is formed to have a width substantially equal to the groove portion 10b of the pulley 10, and the groove portion 10b. It is formed so that it may curve along.

  The hub 13 is formed in a disc shape and is disposed on the inner peripheral surface side of the transmission ring 11. A connecting portion 13 a for connecting the drive shaft 2 is provided on one end surface side of the hub 13, and the drive shaft 2 is fixed to the hub 13 by a nut 13 b that is screwed from the other end surface side of the hub 13. The other end surface of the hub 13 is provided with a plurality of ball grooves 13c that engage the balls 14 so as to be movable in the radial direction at intervals in the circumferential direction, and each ball 14 is provided on the inner surface of the ball groove 13c. Locked in the direction. In this case, a convex portion 13d protruding in the axial direction is provided on the radially outer side of each ball groove 13c, and the convex portion 13d comes into contact with the ball 14 positioned on the radially outer side of the ball groove 13c in the axial direction. ing. In addition, an extending portion 13e extending in a cylindrical shape in the axial direction is provided at the center portion in the radial direction of the other end surface of the hub 13 so as to cover the nut 13b.

  The balls 14 are spaced from each other in the circumferential direction of the hub 13, and are disposed in the ball grooves 13 c of the hub 13.

  The pressing ring 15 is engaged with the extending portion 13e of the hub 13 so as to be movable in the axial direction, and one end surface thereof is in contact with each ball 14. One end surface of the pressing ring 15 is provided with an inclined surface 15a that gradually protrudes in the axial direction from the radially outer side to the inner side, and is positioned on the radially outer side of each of the ball grooves 13c on the radially outer side of the inclined surface 15a. The balls 14 are in contact with each other. A disc spring 15b that engages with the extension 13e of the hub 13 is provided on the other end surface side of the press ring 15, and the press ring 15 is urged toward the ball 14 by the disc spring 15b. The disc spring 15b is disposed in a compressed state between an annular nut 15c that is screwed into the extending portion 13e and the pressing ring 15, and the pressing force of the pressing ring 15 by the disc spring 15b is adjusted by adjusting the tightening force of the nut 15c. The pressure can be set arbitrarily.

  The holding ring 16 is made of synthetic resin formed in an annular shape, and has an outer diameter corresponding to a substantially central portion in the radial direction of each ball groove 13c. That is, the holding ring 16 is disposed between the other end surface of the hub 13 and the pressing ring 15, and engages each ball 14 positioned radially outside the ball groove 13 c from the inside in the radial direction, thereby holding each ball 14. The ball groove 13c is held outside in the radial direction. A plurality of concave portions 16a formed in an arc shape are provided on the inner peripheral surface of the holding ring 16 at intervals in the circumferential direction, and the thickness in the radial direction of the portion where each concave portion 16a is provided is different from that of the other portion. It is smaller than the thickness. In this case, the portion provided with each recess 16a is formed to have a strength that can be broken by the pressure contact of each ball 14 that moves inward in the radial direction of the ball groove 13c when the power is cut off.

  In the above configuration, when engine power is input to the pulley 10, the transmission ring 11 rotates together with the pulley 10. At that time, the rotational force of the pulley 10 is transmitted to the transmission ring 11 via each buffer rubber 12, and each buffer rubber 12 is elastically deformed between the protruding portion 10 c of the pulley 10 and the protruding portion 11 a of the transmission ring 11. As a result, shocks due to sudden rotation fluctuations are absorbed. Further, the rotational force of the transmission ring 11 is transmitted to the hub 13 via the locking ring 11 b and the balls 14, and the drive shaft 2 rotates together with the hub 13. At this time, each ball 14 is pressed radially outward of each ball groove 13c by the inclined surface 15a of the pressing ring 15, and each ball 14 is locked in the circumferential direction on the tapered surface 11c of the locking ring 11b. The rotational force of the transmission ring 11 is transmitted to the hub 13.

  Here, for example, when an excessive rotational load is applied to the pulley 10 side due to, for example, seizure of the compressor, and a torque of a predetermined magnitude or more is generated between the transmission ring 11 and the hub 13, the tapered surface of the locking ring 11b. By the pressing of 11c, each ball 14 moves to the inner side in the radial direction of the ball groove 13c against the pressing force of the pressing ring 15 as shown in FIG. As a result, each ball 14 is held radially inward of the ball groove 13c by the convex portion 13d of the ball groove 13c and the pressing ring 15, and each ball 14 is restrained at a position where it cannot be locked with the locking ring 11b. The transmission ring 11 idles with respect to the hub 13, and the transmission of power from the pulley 10 side to the drive shaft 2 is interrupted. At that time, if each ball 14 moves toward the inner side in the radial direction of the ball groove 13c, the holding ring 16 is broken by the pressure contact of each ball 14 as shown in FIG. 7, and the movement of each ball 14 is allowed. The movement of each ball 14 is not hindered.

  When assembling the power transmission device, the holding ring 16 is arranged on the hub 13 side, and then each ball 14 is arranged in the ball groove 13c. Each ball 14 is held radially outside and does not move radially inward of the ball groove 13c until the pressing ring 15 is assembled.

  As described above, according to the power transmission device of the present embodiment, each ball 14 is held on the radially outer side of the hub 13, and holding that allows the movement of each ball 14 toward the radially inner side of the hub 13 when the power is interrupted. Since the ring 16 is provided, the balls 14 do not move inward in the radial direction of the hub 13 during assembly, and the assembly work can be performed very easily.

  In this case, since the holding ring 16 is formed by an annular member that locks each ball 14 from the inside in the radial direction of the hub 13, all the balls 14 can be held by one holding ring 16, and the structure is simplified. Can be achieved.

  Further, since the retaining ring 16 is formed to be ruptured by the pressure contact of each ball 14 to allow the movement of each ball 14, a complicated structure for allowing the movement of each ball 14 is not required, and the retaining ring 16 is not required. Can be configured at low cost.

  Furthermore, since the plurality of recesses 16a that reduce the thickness in the radial direction are provided on the inner peripheral surface of the holding ring 16 at intervals in the circumferential direction, the holding ring 16 can be easily removed from the portion where each recess 16a is provided. The movement resistance of each ball 14 by the holding ring 16 can be made extremely small.

  In each of the above embodiments, the holding ring 16 is broken by the pressure contact of each ball 14. However, the holding ring formed by the elastic member is deformed by the pressure contact of each ball 14. Also good.

  In each of the above embodiments, the concave portions 16a of the holding ring 16 are formed in an arc shape. However, the present invention is not limited to such a shape. For example, a triangular concave portion 16b shown in FIG. 9 may be provided with a rectangular recess 16c as shown in FIG. 9, or a notch 16d may be provided as shown in FIG. 10 instead of the recess.

  Further, in each of the above embodiments, the power is transmitted to the compressor. However, the present invention can also be applied to a power transmission device used for other rotating devices.

Side surface sectional drawing of the power transmission device which shows one Embodiment of this invention AA sectional view of FIG. Front view of retaining ring Side view of the main part of the power transmission device Front view of main part of holding ring showing ball holding state Side sectional view of the main part showing the operation when power is shut off Front view of main part of retaining ring showing broken state Main part front view showing a modified example of the retaining ring The principal part front view which shows the other modification of a holding ring The principal part front view which shows the other modification of a holding ring

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Transmission ring, 13 ... Hub, 14 ... Ball | bowl, 15 ... Press ring, 16 ... Holding ring, 16a, 16b, 16c ... Recessed part, 16d ... Notch part.

Claims (4)

An annular drive-side rotator that is rotated by power from the outside, a driven-side rotator that is disposed on the inner peripheral surface side of the drive-side rotator, and a plurality that transmits the rotational force of the drive-side rotator to the driven-side rotator. And a pressing member that presses each ball in the axial direction, and the balls pressed by the pressing member are locked to the inner peripheral surface side of the driving side rotating body, thereby reducing the rotational force of the driving side rotating body. When the torque is transmitted to each ball and a torque of a predetermined magnitude or more is generated between the driving side rotating body and the driven side rotating body, each ball locked to the driving side rotating body is resisted against the pressing force of the pressing member. By moving the driven-side rotator radially inward, the drive-side rotator and the balls are unlocked, and the power transmitted from the drive-side rotator to the driven-side rotator is cut off. In the transmission device,
Each of the balls is held on the radially outer side of the driven-side rotator, and when a torque of a predetermined magnitude or more is generated between the drive-side rotator and the driven-side rotator, the radially inner side of the driven-side rotator is generated. A power transmission device comprising a holding member that allows movement of each of the balls. The power transmission device according to claim 1, wherein the holding member is formed by an annular member that locks each ball from the radially inner side of the driven-side rotator. 3. The power transmission device according to claim 1, wherein the holding member is formed to be broken or deformed by pressure contact of each ball to allow movement of each ball. The power transmission device according to claim 3, wherein the holding member is provided with a plurality of recesses that reduce the thickness in the radial direction at intervals in the circumferential direction.

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