JP4493576B2 - Power transmission device - Google Patents

Description

  The present invention relates to a power transmission device that transmits a rotational force of an automobile engine or the like to a compressor or the like.

In general, the power of an automobile engine (rotation drive source) is transmitted to an air conditioning compressor (driven device) via a power transmission device, and the interior of the vehicle is air-conditioned by driving the compressor. When this compressor is a variable capacity type, the rotational force of the engine is transmitted to the pulley via the belt, and the rotational force transmitted to the pulley is a power cutoff function (functions when the compressor is overloaded such as a compressor lock). ) And is further transmitted from the leaf spring member to the shaft of the compressor through the hub and used as the rotational force of the compressor.
JP 2001-32903 A

  By the way, the rotational force of the engine is not constant but fluctuates in torque, and this torque fluctuation is absorbed by the shock absorber of the power transmission device. This shock absorber has a rubber shock absorbing material, a nut that is fixed through the shock absorbing material, and a bolt that is screwed into the nut and fastens the leaf spring member to the pulley, and absorbs torque fluctuations with the shock absorbing material. On the other hand, the leaf spring member is connected to the pulley with bolts and nuts to give a stable rotational force to the hub and the shaft of the compressor.

  However, this power transmission device has a structure in which the leaf spring member is directly connected to the pulley by a bolt. Therefore, the fall of the nut that occurs when absorbing torque fluctuations depends only on the fastening force of the leaf spring member and the bolt. As a result, shear stress concentrates on the contact portion between the leaf spring member and the bolt, and the leaf spring member may be damaged.

  An object of the present invention is to provide a power transmission device capable of preventing a leaf spring member from being damaged by suppressing a fall phenomenon of a nut in view of the conventional problems.

  In order to solve the above-mentioned problems, the present invention provides a pulley to which a rotational force of a rotational drive source is applied, a leaf spring member connected to the pulley via a shock absorber, and a leaf spring member. And a hub that freely connects and transmits the rotational force transmitted to the leaf spring member to the driven device, and the shock absorber includes an elastic shock absorber that absorbs the torque fluctuation of the pulley, a nut that penetrates the shock absorber, and a nut In a power transmission device having a damper comprising a bolt that is screwed to fasten a leaf spring member to a pulley, a spacer plate is interposed between the leaf spring member and the pulley, and a bolt is inserted between both axial ends of the nut. One end of the side is structured to be separated from the spacer plate.

  According to the invention of claim 1, since the leaf spring member is bolted to the pulley via the spacer plate, the fall of the nut is suppressed by the spacer plate in addition to the leaf spring member. The damage of the is suppressed.

  According to the first aspect of the present invention, when the bolt is screwed onto the nut, the nut moves toward the spacer plate while compressing the buffer material as the screwing operation proceeds. Thereafter, the nut hits the spacer plate, and the leaf spring member is fixed to the pulley via the spacer plate. When the leaf spring member is in a fixed state, the cushioning material is in a compressed state, so an anti-compression force is applied to the nut, and this anti-compression force moves the bolt toward the nut. Acts as a force to cause Therefore, the spacer plate is always pressed against the pulley, the leaf spring member is firmly fastened to the pulley, and the nut falling phenomenon is suppressed.

  The invention according to claim 2 is the power transmission device according to claim 1, since the thickness dimension of the spacer plate is larger than the thickness dimension of the leaf spring member, the deformation of the spacer plate is prevented, and the fastening strength by the bolt Is further improved.

  According to a third aspect of the invention, in the power transmission device of the first or second aspect, a plurality of dampers are provided in the circumferential direction of the pulley, and the spacer plate is formed of a common member for each damper. The nut falling phenomenon that occurs is interfered with each other by the common spacer plate, and the nut falling phenomenon is further suppressed.

  According to the present invention, since the leaf spring member and the pulley are bolted via the spacer plate, the fall of the nut is suppressed by the spacer plate in addition to the leaf spring member, and the breakage of the leaf spring member is suppressed. Has the advantage of.

  1 to 6 show a first embodiment of a power transmission device according to the present invention. FIG. 1 is a sectional view of the power transmission device, FIG. 2 is an enlarged sectional view of a main part of the present invention, and FIG. FIG. 4 is a plan view showing the leaf spring member, FIG. 5 is a plan view showing the spacer plate, and FIG. 6 is a plan view showing the correspondence between the leaf spring member and the spacer plate. 7 (a) and 7 (b) are enlarged cross-sectional views of the main part showing the fastening operation of the leaf spring member performed using a modification of the nut.

  The power transmission device 10 according to the present invention transmits the rotational force of an automobile engine (external drive source) to a variable displacement compressor (driven device), and the engine rotational force is normally transmitted to the compressor. On the other hand, when the compressor breaks down due to a lock or the like, the power shut-off function works to prevent transmission of the rotational force and protect the compressor and the like. Such a power transmission device 10 will be described below with reference to FIG.

  The power transmission device 10 has an annular pulley 11 having a substantially U-shaped cross section, and a belt (not shown) to which the rotational output of the engine is transmitted is stretched around the pulley 11. The pulley 11 is pivotally supported on the front housing 20 of the compressor via a bearing 11a, and the pulley 11 is rotated by the rotational force of the belt. The front plate 111 of the pulley 11 has a plurality of through holes 111a for penetrating bolts and nuts at intervals in the circumferential direction.

  A shock absorber 12 is installed inside the pulley 11. The structure of the shock absorber 12 will be described in detail with reference to FIGS. The shock absorber 12 has a damper holding member 121 formed in an annular shape along the inside of the pulley 11 and a plurality of dampers 122 of the damper holding member 121.

  The damper holding member 121 is formed of a plastic material, and a cylindrical holding member main body 121a formed annularly along the inside of the pulley 11 and a plurality of cylindrical members formed at intervals in the circumferential direction of the holding member main body 121a. And a damper cover 121b. The holding member main body 121a is fixed to the pulley 11 with a rivet 121c. The damper cover 121b is disposed so as to face the through holes 111a, and a damper 122 is disposed inside the damper cover 121b.

  The damper 122 includes a nut 122a penetrating the inside of the damper cover 121b, a bolt 122b screwed into the inner surface of the nut 122a, and a damper rubber (buffer material) 122c interposed between the inner surface of the damper cover 121b and the outer surface of the nut 122a. And have. The front end of the nut 122a (one end on the insertion side of the bolt 122b) passes through the through hole 111a, and the rear end has a damper pressing portion 122d extending in the radial direction. A damper rubber 122c is disposed between the front plate 111 and the front plate 111. The bolt 122b is inserted from the tip of the nut 122a and is screwed so as to be able to advance and retract in the axial direction of the nut 122b.

The rotational force transmitted to the shock absorber 12 is transmitted to the elastic leaf spring member 13. The leaf spring member 13 is connected to the front plate 111 of the pulley 11 via the spacer plate 14. That is, the leaf spring member 13, as shown in FIG. 4, an annular spring body 131, and three inclined portion 132 extending integrally from the outer peripheral edge of the spring body 131, of the inclined portions 13 2 tip And a bolt hole 132a through which the bolt 122b penetrates is formed in the base of the inclined portion 132. On the other hand, as shown in FIG. 5, the spacer plate 14 includes an annular plate body 141 and three attachment portions 142 that protrude radially from the plate body 141, and bolts 122 b penetrate the attachment portions 142. Bolt holes 142a are formed. Here, the correspondence relationship between the leaf spring member 13 and the spacer plate 14 will be described with reference to FIG. 6. The bolt holes 132 a and 142 a face each other vertically, and the base portion of the inclined portion 132 of the leaf spring member 13 and the spacer plate. The 14 attachment portions 142 are vertically overlapped and fixed to the front plate 111 of the pulley 11.

  The rotational force transmitted to the leaf spring member 13 is transmitted to the hub 15. The hub 15 has a cylindrical connecting portion 151 and a flange portion 152 extending in the radial direction from the tip of the connecting portion 151. The connecting portion 151 is connected to the shaft 21 of the compressor so that when the hub 15 rotates, the shaft 21 also rotates at the same time. A pressing member 16 urged toward the back surface is installed on the back side of the flange portion 152, and an engagement hole 161 is formed at the tip of the pressing member 16. Here, the projecting portion 134 of the leaf spring member 13 is freely detachable between the flange portion 152 and the engaging hole 161, and when the projecting portion 134 is engaged with the engaging hole 161, The rotational force of the leaf spring member 13 is transmitted to the hub 15. When the compressor is locked due to a failure, the force applied to the projecting portion 134 becomes larger than the pressing force of the pressing member 16, and the projecting portion 134 is disengaged from between the flange portion 152 and the engagement hole 161, and the hub 15 Transmission of rotational force to is prevented.

  According to this embodiment, the torque fluctuation transmitted to the pulley 11 is buffered by the damper 122 of the shock absorber 12, and the buffered rotational force is transmitted to the leaf spring member 13 via the spacer plate 14. When the torque fluctuation is buffered, the nut 122a falls, and the bolt 122b tends to tilt in the circumferential direction of the pulley as shown by a two-dot chain line in FIG. However, in this embodiment, since the spacer plate 14 is interposed between the leaf spring member 13 and the pulley 11 (front plate 111), the falling phenomenon of the nut 122a is also caused by the spacer plate 14 in addition to the leaf spring member 13. This suppresses the breakage of the leaf spring member 13.

  Further, since the spacer plate 14 is formed of a member common to each damper 122, the falling phenomenon of the nut 122a occurring in each damper 122 is interfered with each other by the spacer plate 14, and the falling phenomenon of the nut 122a is further suppressed.

  Further, the nut may be improved as shown in the modification of FIGS. 7 (a) and 7 (b). That is, the nut 122a 'according to the modified example has a structure in which the tip is separated from the spacer plate 14 as shown in FIG.

  According to this modification of the nut, when the bolt 122b is screwed into the nut 122a ′, the bolt 122b is placed on the inner surface of the nut 122a ′ until the bolt 122b hits the leaf spring member 13, as shown in FIG. The position of the nut 122a ′ remains unchanged only by moving along the axial direction.

  After the bolt 122b hits the leaf spring member 13 by continuing the screwing operation of the bolt 122b, the axial movement of the bolt 122b is restricted by the leaf spring member 13 and the spacer plate 14, so that FIG. As indicated by the white arrow, the nut 122a ′ moves in the direction opposite to the traveling direction of the bolt 122b while compressing the damper rubber 122c. The tip of the nut 122 a ′ is in pressure contact with the back surface of the spacer plate 14, and the leaf spring member 13 is fixed to the pulley 11.

  Thus, when the leaf spring member 13 is in a fixed state, the damper rubber 122c is in a compressed state. The compression force of the damper rubber 122c is applied as an anti-compression force to the nut 122a ', and further, this anti-compression force acts as a force for moving the bolt 122b in the direction of the nut 122a'. Therefore, the spacer plate 14 is always pressed against the pulley 11, the leaf spring member is firmly fastened to the pulley 11, and the fall phenomenon of the nut 122a 'is further suppressed.

  FIG. 8 shows a second embodiment of the power transmission device according to the present invention and is an enlarged cross-sectional view of a main part showing a fastening state of a leaf spring member. Note that the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  In this embodiment, the thickness dimension of the spacer plate is improved. That is, the thickness dimension of the spacer plate 14 and the leaf spring member 13 according to each of the embodiments is substantially equal as shown in FIGS. 2, 3, and 7A and 7B. On the other hand, in this embodiment, as shown in FIG. 8, the spacer plate 14 ′ is formed of a thick member, and the thickness dimension of the spacer plate 14 ′ is larger than the thickness dimension of the leaf spring member 13. It is set.

  According to this embodiment, the strength of the spacer plate 14 ′ is increased by increasing the thickness dimension of the spacer plate 14 ′. Thereby, the deformation of the spacer 14 'is almost eliminated, and the nut collapse is further suppressed. Other configurations and operations are the same as those in the first embodiment.

  Although not shown, in the second embodiment, the damper rubber 122c having a larger thickness in the width direction is used, and the damper rubber 122c is interposed between the damper cover 121b and the nut 122a. You may do it. In this case, the elastic force of the damper rubber 122c is further increased, and the nut falling phenomenon is further suppressed.

Sectional drawing of the power transmission device which concerns on 1st Embodiment The principal part expanded sectional view concerning a 1st embodiment Sectional view in the direction of arrows AA in FIG. The top view which shows the leaf | plate spring member which concerns on 1st Embodiment. The top view which shows the spacer board which concerns on 1st Embodiment. The top view which shows the correspondence of the leaf | plate spring member which concerns on 1st Embodiment, and a spacer board. The principal part expanded sectional view which shows the fastening operation of the leaf | plate spring member performed using the modification of the nut which concerns on 1st Embodiment. The principal part expanded sectional view concerning 2nd Embodiment

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Power transmission device, 11 ... Pulley, 12 ... Shock absorber, 13 ... Leaf spring member, 14 ... Spacer plate, 15 ... Hub, 122 ... Damper, 122a ... Nut, 122b ... Bolt, 122c ... Damper rubber

Claims (3)

A pulley to which the rotational force of the rotational drive source is applied, a leaf spring member connected to the pulley via a shock absorber, and a rotational force transmitted to the leaf spring member that is detachably connected to the leaf spring member is driven. A shock absorber that absorbs torque fluctuations of the pulley, and a nut that passes through the shock absorber and is interposed between the shock absorber and the pulley. And a power transmission device having a damper comprising a bolt screwed to the nut and fastening the leaf spring member to the pulley,
A spacer plate is interposed between the leaf spring member and the pulley, and one end on the insertion side of the bolt among the axial ends of the nut is screwed into the nut by the screwing operation of the bolt. It is separated from the spacer plate until it comes into contact with the leaf spring member, and after the bolt comes into contact with the leaf spring member, the nut moves against the elasticity of the cushioning material so as to contact the spacer plate. A power transmission device characterized by. The power transmission device according to claim 1, wherein a thickness dimension of the spacer plate is larger than a thickness dimension of the leaf spring member. The power transmission device according to claim 1, wherein a plurality of the dampers are provided in a circumferential direction of the pulley, and the spacer plate is formed of a member common to the dampers.

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