JP4561595B2 - Power transmission device - Google Patents

Description

  The present invention relates to a power transmission device that transmits power (torque) from a drive source to a rotating device, and more particularly, to a rotating device such as a compressor of a vehicle air conditioner disposed in a vehicle. (Torque) is suitably used for a power transmission device.

  As a prior art, a power transmission device shown in FIG. In this conventional power transmission device, as shown in FIG. 10, a plurality of protrusions 31 protruding toward the hub side are provided on the pulley 3, which is a driving side rotating member that rotates by receiving power from a driving source. It is integrally formed with a gap in the circumferential direction. On the other hand, it also projects toward the pulley side and is supplied from the pulley side to the hub 4 that is a driven side rotating member fixed to the rotating shaft on the rotating device side. A plurality of protrusions 41 that receive torque are integrally formed at intervals in the circumferential direction. When the pulley 3 and the hub 4 are mounted, the protrusions 31 of the hub 3 and the protrusions 41 of the pulley 4 are provided. Are mutually displaced around the rotation axis by shifting in the rotation direction of the rotation axis. The first and second dampers (torque transmission members) 11 and 12 connected by the connecting member 13 are arranged between the protrusions 31 and 41 so as to be sandwiched between the protrusions. Torque is transmitted between the hub 4 and the hub 4.

  In the power transmission device having such a structure, as shown in FIG. 11A, the first damper 11 has a direction in which the pulley 3 rotates relative to the hub 4 (forward rotation) when the rotating device is driven. When rotating in the direction), the projecting portion 31 of the pulley 3 undergoes compressive deformation under a compressive load and transmits torque to the projecting portion 41 of the hub 4.

  On the other hand, as shown in FIG. 11B, the second damper 12 receives a compressive load when the pulley 3 rotates in the reverse direction (reverse direction) relative to the hub 4. To compress and deform. The size of the first and second dampers 11 and 12 in the compressive load direction, the dimension between the two protrusions 31 and 41, and the like are as follows when the first damper 11 is in contact with both the protrusions 31 and 41. The second damper 12 is separated from at least one of the protrusions 31 and 41 with a predetermined gap g.

  Thus, in the power transmission device having the conventional structure, a predetermined gap g is provided as shown in FIG. 10 in order to ensure the fatigue limit strength of the component due to excessive torque fluctuation. Accordingly, by repeating positive torque (see FIG. 11A) and negative torque (see FIG. 11B) due to engine rotation fluctuation, the protrusion 41 of the hub 4 and the damper 11 (12) are connected. Tapping behavior occurs. There is a problem that the hub 4 vibrates due to this impact, and abnormal noise is generated.

  On the other hand, as a prior art, Patent Document 2 discloses a soundproof cover that is attached to a rotating member such as a pulley or a hub of a torsional damper and shields noise generated in the rotating member. However, in the pulley described in Patent Document 2, the pulley and the hub are not connected in the circumferential direction via the elastic member and the gap g as in the present invention. There is no abnormal noise that collides with the elastic member.

JP 2004-144226 A JP-A-11-37218

  The present invention has been made in view of the above problems, and its purpose is to insulate abnormal noise generated in the power transmission portion between the hub and the pulley, and to be easily attached and detached and to fall off. It is to provide a power transmission device with no sound insulation cover.

The present invention provides a power transmission device according to each of the claims as means for solving the problems.
The power transmission device according to claim 1 is a pulley 3 that is rotationally driven by a drive source, a hub 4 that is connected to a rotation shaft 81 of a driven device 8, and an elastic member for torque transmission that is interposed between the pulley and the hub. 1, and the pulley 3 and the hub 4 are connected in the circumferential direction via the elastic member 1 and the gap g, and the cover body 5 covers the connecting portion between the pulley and the hub. , 5A to 5D, and this cover body 5A is composed of a rubber cover member 51 and an annular ring 52 bonded to the outer periphery of the cover member and partially having a notch 52a. It is assembled in an annular groove 32 provided on the front side of the pulley 3, and an opening 51b is provided on the peripheral side edge of the cover member 51. The cover member 51 includes a disk portion whose outer edge portion forms an annular shape, Rotates from the outer edge of this disk 81, and an end portion of the side wall portion is bonded to the annular ring 52, and the opening 51b extends in an axial direction from the end portion of the side wall portion to the outer edge portion of the disk portion. And a rectangular shape extending from the outer edge toward the center of the disk portion . As a result, the hub 4 vibrates by the impact of the hub 4 and the elastic member 1 generated by repeating positive torque and negative torque due to fluctuations in the rotation of the engine as the drive source, and the generated abnormal noise can be insulated. . Further, the cover body 5A can be easily assembled to the groove 32 of the pulley 3 by reducing the diameter of the ring 52, and the cover body 5A can be easily attached to and detached from the pulley. Also, the fact that the cover body 5A is assembled in the groove 32 of the pulley 3 using the pressing force of the ring determines the material and dimensions of the ring that the ring 52 does not rotate when the pulley 3 rotates. For this reason, abrasion of the pulley 3 can be prevented and the cover body 5A can be prevented from falling off the pulley. Furthermore, since the opening 51b is provided in the cover body 5A, the heat generated in the space closed by the cover body can be released, and the temperature increase of the power transmission device can be prevented.

In the power transmission device according to claim 2, the annular ring 52 is configured such that the distance between the end portions 52b of the annular ring 52 facing the notch 52a is shortened toward the center of the disk portion. Is.
The power transmission device according to claim 3 is configured such that both ends 52b of the ring 52 facing the notch 52a are not covered with the cover member 51, whereby the both ends 52b of the ring 52 are easily gripped. The cover body 5A can be assembled to the pulley 3 without damaging the cover member 51.

  In the power transmission device according to the fourth aspect, a plurality of openings 51b are formed at intervals around the periphery of the cover member 51, thereby increasing the temperature in the space closed by the pulley 3 and the cover body 5A. It is possible to prevent the abnormal noise and the temperature rise at the same time. Further, as in claim 5, even if the circular hole 51c is formed in the substantially central portion of the cover member 51, the temperature rise in the space closed by the pulley 3 and the cover body 5A can be prevented, The problem of abnormal noise and temperature rise can be solved simultaneously.

  A power transmission device according to an embodiment of the present invention will be described below with reference to the drawings. The power transmission device of the present invention is suitable for being assembled to a compressor of a vehicle air conditioner, and will be described as being assembled to the compressor in the following description. FIG. 1 is a longitudinal sectional view of an upper half of a power transmission device according to an embodiment of the present invention. The power transmission device of the present invention includes a pulley 3 that is a driving side rotating member that obtains power from an engine or motor that is a driving source, and a hub 4 that is a driven side rotating member fixed to a rotating shaft 81 of a compressor 8. Power (torque) is transmitted between the two. The pulley 3 and the hub 4 are provided on the same axis.

  The pulley 3 is rotatably mounted via a bearing 7 on a cylindrical portion 82 a provided on one end side of the casing 82 of the compressor 8. The pulley 3 includes a pulley body 3a preferably formed of a thermoplastic synthetic resin and a ring-shaped sleeve 3b formed of a metal material such as iron, and these are integrally formed by, for example, insert molding. . In addition, an annular pocket portion 3c for accommodating and holding an elastic member (damper) 1 for torque transmission is formed on the front side of the pulley 3 (left side in FIG. 1). Furthermore, a plurality of protrusions 31 are integrally formed on the pulley 3 at intervals in the circumferential direction, protruding toward the hub 4 so as to be accommodated in the pocket portion 3c as in the conventional example of FIG. ing.

  Further, a belt (not shown) is wound around the outer peripheral surface of the pulley 3 and is rotated by power from the outside such as an engine or a motor. The bearing 7 is fitted in the cylindrical portion 82a of the casing 82, and is prevented from moving in the axial direction by a snap ring 71 fitted in a groove formed on the outer peripheral surface of the cylindrical portion 82a. Further, the casing 82 and the rotary shaft 81 of the compressor 8 are sealed by a shaft seal device 83 to prevent leakage of refrigerant, oil, and the like inside the casing 82.

  A torque limiter 9 integrally formed by sintering metal powder is fixed to the tip of the rotary shaft 81 of the compressor 8. The torque limiter 9 includes an inner part 91 that is fitted and connected to the rotary shaft 81, an outer part 92 that is connected to the hub 4, and a bridge part 93 that connects the inner part 91 and the outer part 92. The inner portion 91 has a cylindrical shape, and a female screw portion, for example, is formed on the inner peripheral surface thereof. The inner shaft 91 is screwed with a male screw portion formed on the outer peripheral surface of the rotary shaft 81, so that the rotary shaft 81 is connected. On the other hand, the outer portion 92 is coupled to the hub 4 by injection molding. In FIG. 1, a plurality of bridge portions 93 that are visible in the back are provided, and are set to have such a strength as to be broken when the transmission torque exceeds a predetermined torque.

  As shown in the conventional example of FIG. 10, a plurality of protrusions 41 are integrally formed on the hub 4 at intervals in the circumferential direction protruding toward the pocket portion 3 c of the pulley 3. Therefore, in a state where the pulley 3 and the hub 4 are mounted on the compressor 8, the protrusion 41 of the hub 4 and the protrusion 31 of the pulley 3 are mutually in the rotational direction of the rotation shaft 81 as shown in FIG. They are displaced and positioned alternately around the rotation axis 81.

  The first and second elastic members (first and second dampers) 11 and 12 are disposed between the projecting portions 31 and 41 so as to be sandwiched between the first and second elastic members 11. , 12 are connected by a connecting member 13. That is, the first and second elastic members 11 and 12 and the connecting member 13 are integrally formed in a bifurcated shape to constitute an elastic member (damper) 1 and act as a torque transmission member. The elastic member 1 is made of an elastically deformable material such as ethylene / propylene / diene terpolymer rubber (EPDM).

As described above, the first and second elastic members 11 and 12 arranged in this way receive both positive torque and negative torque repeatedly due to engine rotation fluctuations, and both protrusions 31 and 41. It compresses and deforms between them, and transmits torque from the pulley 3 to the hub 4.
The first elastic member 11 is in contact with both protrusions 31 and 41 in terms of the size of the first and second elastic members 11 and 12 in the compressive load direction and the size between the protrusions 31 and 41. In some cases, the second elastic member 12 is selected to be separated from at least one of the protrusions 31 and 41 with a predetermined gap g. For this reason, every time a positive torque and a negative torque are repeated, the protrusion 41 of the hub 4 and the elastic member 1 are struck, and the hub 4 vibrates by this impact, and abnormal noise is generated. In FIG. 10, the elastic member 1 is provided so as to be fitted to the protruding portion 31 of the pulley 3, but the elastic member 1 is provided so as to be fitted to the protruding portion 41 of the hub 4. Is the same.

  Therefore, in the present invention, the cover body 5 is attached to the front surface (front side) of the power transmission device so as to cover the connection portion between the hub 4 and the pulley 3 in order to insulate abnormal noise. FIG. 2 is a front view of the cover body 5 according to the first embodiment, and FIG. 3A is a view for explaining the attachment of the cover body 5 to the pulley 3. The cover body 5 includes a circular shallow dish-shaped cover member 51 formed of rubber, for example, EPDM, and an annular ring 52 that is bonded to the periphery of the cover member 51 and is partially formed with a notch 52a. It is composed of The ring 52 is made of a metal material, for example, SUS304 stainless steel. The cover member 51 and the ring 52 are preferably integrally formed during vulcanization. The cover member 51 and the ring 52 are joined together so that the inner peripheral surface and one side surface of the ring 52 are joined to the cover member 51 as shown in FIG.

  In the cover body 5 of the first embodiment, a cup-shaped raised portion 51 a for avoiding the protruding tip of the rotating shaft 81 is formed at a substantially central portion of the cover member 51. In order to assemble the cover body 5 to the pulley 3, as shown in FIG. 3A, an annular groove 32 is provided on the inner surface of the pulley 3 in front of the pocket portion 3 c, and the cover member 51 is formed in the groove 32. The cover body 5 is assembled to the pulley 3 by fitting the peripheral edge (ring 52). In this case, the diameter of the groove 32 is smaller than the outer shape of the ring 52. As an assembling method, the notch 52 a is used to reduce the diameter of the ring 52, that is, the cover member 5, and the peripheral edge thereof is fitted into the groove 32 of the pulley 3.

FIG. 4 shows a cover body 5A of the second embodiment. In the cover body 5 of the first embodiment, the front side of the pulley 3 is completely closed, and there is a concern about the temperature rise in the space closed by the pulley 3 and the cover body 5 due to heat generated by the bearing 7 or the like. . Therefore, the basic structure that the cover body 5A of the second embodiment is composed of a circular shallow dish-shaped cover member 51 and an annular ring 52 formed with a notch 52a is the same as the cover body of the first embodiment. 5, in the cover body 5 </ b> A of the second embodiment, a plurality of openings 51 b are formed in the circumferential edge of the cover member 51 at intervals in the circumferential direction. A circular hole 51c is provided in place of the cup-shaped raised portion 51a formed at the substantially central portion of the cover member 51. The diameter of the circular hole 51 c is slightly larger than the shaft diameter of the rotating shaft 81.
Furthermore, both ends of the ring 52 facing the notch 52a are exposed portions 52b that are not covered with the cover member 51 in consideration of ease of gripping during assembly. Therefore, in the cover body 5A of the second embodiment, since the space closed by the pulley 3 and the cover member 51 is not completely sealed, the sound insulation is somewhat inferior to the cover body 5 of the first embodiment. However, temperature rise in the space can be prevented.

  FIG. 5 is a graph comparing the effects when the cover body 5 of the first embodiment is provided and when the cover body is not provided. That is, the abnormal noise is reproduced on the bench simulating the rotational fluctuation of the actual vehicle engine, and the abnormal noise level is measured. In the figure, the vertical axis represents the abnormal sound level (dB), and the horizontal axis represents the frequency (Hz). A thin solid line indicates a case where the cover body is not attached, and a thick solid line indicates a case where the cover body 5 which is not provided with the opening and the circular hole of the first embodiment is attached. As can be seen from this graph, when the cover body 5 of the first embodiment is mounted, the abnormal noise is reduced by 22 (dB) compared to the case where the cover body is not mounted.

  FIG. 6 is a graph comparing the effects obtained when the cover body 5A of the second embodiment is provided and when the cover body is not provided. The test method is the same as in FIG. In the drawing, a thin solid line indicates a case where the cover body is not mounted, and a thick solid line indicates a case where the cover body 5A provided with the opening and the circular hole of the second embodiment is mounted. As can be seen from this graph, when the cover body 5A of the second embodiment is mounted, the abnormal noise is reduced by 15 (dB) compared to the case where the cover body is not mounted. Therefore, the cover body 5 of the first embodiment is slightly better than the cover body 5A of the second embodiment in terms of sound insulation measures, but the cover body 5A of the second embodiment also has a sufficient noise level. In addition to being able to lower it, you can take precautions against fever.

  FIG. 7 shows a cover body 5B of the third embodiment. The cover body 5B of the third embodiment is made of an aluminum material instead of the rubber material of the first and second embodiments. That is, the cover body 5B is formed by adhering the disk-shaped aluminum tape 53 to the entire front side of the hub 4 including the torque limiter 9. In this case, since the cover 5B is made of an aluminum material, a heat dissipation effect can be expected in addition to the sound insulation effect.

  FIG. 8 shows an upper half vertical cross-sectional view of the power transmission device equipped with the cover body 5C of the fourth embodiment. The cover body 5C of the fourth embodiment is formed from a disk-shaped laminated plate 54 containing glass fibers. As in the second embodiment, the cover body 5C has a circular hole 54a formed in the substantially central portion thereof, and the peripheral edge thereof is bonded to the front end surface of the pulley 3.

  FIG. 9 shows a plan view and a cross-sectional view of the cover body 5D of the fifth embodiment. The cover body 5D of the fifth embodiment is formed by pressing a cover body having substantially the same shape as the cover body 5 of the first embodiment using an iron material. Since the cover body 5D cannot be assembled to the pulley 3 due to the reduced diameter, the groove 32 provided in the pulley 3 described above is a recessed portion whose front side is open over the entire surface, and the cover body 5D is fitted into the recessed portion. After that, the cover body 5 </ b> D is fixed to the pulley 3 with the circlip 56. Note that a cup-like raised portion 55 similar to that of the first embodiment is formed at a substantially central portion of the cover body 5D. Further, in the case of the metal cover body 5D, the cover body 5D itself may vibrate and become a new different sound source.

As described above, the present invention has the following effects.
(1) Since a cover body in which an elastic member is bonded to a ring with a notch is used, it is possible to add an anti-noise function that can be easily assembled. In addition, since there is no major change in the compressor and the power transmission device, it is possible to quickly cope with abnormal noise.
(2) By using an elastic member as the material, it is possible to prevent the generation of new abnormal noise.
(3) The noise level can be lowered by closing the sound source.
(4) The foreign member can be prevented from entering by covering the rotating member.
(5) Since the ring end is not covered with rubber, it is easy to grip the ring end, and the cover member can be easily assembled to the rotating member.
(6) Since the opening or hole is provided in the cover body, the heat generated in the space closed by the cover body can be released, and the temperature increase of the power transmission device can be prevented.

It is an upper half longitudinal cross-sectional view of the power transmission device of embodiment of this invention. It is a top view of the cover body of the 1st example used for the power transmission device of the embodiment of the present invention. (A) is a figure explaining the state which assembled | attached the cover body to the pulley, (b) is a figure explaining joining of a cover member and a ring. (A) is a top view of the cover body of 2nd Example, B arrow directional view, C arrow directional view, (b) is sectional drawing which shows the AA 'cross section of (a), ( c) is a detailed view of the vicinity of the cutout of the ring of the cover body. It is a graph which compares the effect of the case where the cover body of 1st Example is mounted | worn with the case where a cover body is not mounted | worn. It is a graph which compares the effect of the case where the cover body of 2nd Example is mounted | worn with the case where a cover body is not mounted | worn. It is a front view of the power transmission device which equipped the cover body of 3rd Example. It is an upper half longitudinal cross-sectional view of the power transmission device which attached the cover body of 4th Example. It is the top view and sectional drawing of the cover body of 4th Example. They are the side view (a) cut away partially of the power transmission device of a prior art, and DD sectional drawing (b). It is a figure explaining the operation | movement at the time of (a) forward rotation and (b) reverse rotation of the power transmission device of a prior art.

Explanation of symbols

1 Elastic member (damper, torque transmission member)
11 First elastic member (first damper)
12 Second elastic member (second damper)
DESCRIPTION OF SYMBOLS 13 Connection member 3 Pulley 3a Pulley main body 3b Sleeve 3c Pocket part 31 Projection part 32 Groove 4 Hub 41 Projection part 5,5A-5D Cover body 51 Cover member 51a Protrusion part 51b Opening part 51c Circular hole 52 Ring 52a Notch 52b Exposed part (edge)
7 Bearing 8 Compressor 81 Rotating shaft 82 Housing 9 Torque limiter 91 Inner part 92 Outer part 93 Bridge part

Claims (5)

A pulley (3) that is rotationally driven by a drive source;
A hub (4) connected to the rotating shaft (81) of the driven device (8);
An elastic member (1) for torque transmission interposed between and held by the pulley (3) and the hub (4);
In the power transmission device, wherein the pulley and the hub are connected to each other in the circumferential direction via the elastic member (1) and the gap (g).
A cover body (5, 5A to 5D) that covers a connection portion between the pulley (3) and the hub (4) is provided , the cover body (5A) is a cover member (51) made of rubber, and the cover member And an annular ring (52) having a notch (52a) in part, and the annular ring (52) of the cover body (5A) is disposed on the front side of the pulley (3). Assembled in the annular groove (32) provided, and
An opening (51b) is provided at the peripheral edge of the cover member (51); and
The cover member (51) includes a disk part having an annular outer edge part, and an annular side wall part extending in the axial direction of the rotary shaft (81) from the outer edge part of the disk part, and the end of the side wall part The part is bonded to the annular ring (52), and
The opening (51b) has a rectangular shape that rises in the axial direction from the end of the side wall to the outer edge of the disk, and extends from the outer edge toward the center of the disk.
A power transmission device characterized by that. The annular ring (52) is characterized in that the distance between the end portions of the annular ring (52b) facing the notch (52a) becomes shorter as both end portions (52b) of the annular ring are directed toward the center of the disk portion. The power transmission device according to claim 1. The power transmission device according to claim 1 or 2 , wherein both ends (52b) of the annular ring facing the notch (52a) are not covered with the cover member (51). 4. The power transmission device according to claim 1, wherein a plurality of the openings (51 b) are formed at intervals on a peripheral edge of the cover member (51). The circular hole (51c) of a diameter a little larger than the said rotating shaft (81) is formed in the approximate center part of the said cover member (51), The Claim 1 thru | or 4 characterized by the above-mentioned. Power transmission device.

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