JP2009264491A - Power transmission device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power transmission device having stable torque cutting-off performance while suppressing an increase of cut-off torque by suppressing the appearance of corrosive organisms on a contact face between an extraction member and a member to which one end thereof is connected, with easy and inexpensive treatment. <P>SOLUTION: The power transmission device is provided with: the extraction member to be extracted during cutting off torque; and a fastening member for extractively fastening one end of the extraction member to a driving side member or a driven side member when transmission torque exceeds a set value. Surface treatment is applied to the contact face of the driving side member or the driven side member with the extraction member to suppress the appearance of the corrosive organisms. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a power transmission device that transmits torque from a drive-side member to a driven-side member so that the torque transmission can be interrupted when the transmitted torque exceeds a set value.

  As a power transmission device having a torque cutoff function, for example, a power transmission device (torque limiter) that transmits a driving force from a drive source to a compressor so that the torque transmission can be cut off when the transmission torque becomes excessive is known. It is described in Document 1, Patent Document 2, Patent Document 3, and the like. In the power transmission devices described in these patent documents, the driving force of the driving side member is transmitted to the driven side member via the connecting member (pulling member), but the transmission torque exceeds the set value and is excessive. At this time, for example, one end of the connecting member is pulled out from the driving side member or the driven side member that has been connected so far, and the driving side member is idled so that the transmission torque is cut off.

Such power transmission devices are often provided in places exposed to harsh conditions, such as for power transmission to a compressor for a vehicle air conditioner, and are durable enough to cope with the environment and changes in the environment, In particular, corrosion resistance is often required. In particular, in the case of having a mechanism including the above-described extraction member, high corrosion resistance is required between the contact surface of the extraction member and the member to which the extraction member is fixed, and when the corrosion resistance of the contact surface portion is low, When the pullout member is pulled out for torque cutoff, the pullout resistance greatly fluctuates, and the target cutoff torque value may fluctuate significantly. Conventionally, in order to satisfy this corrosion resistance, a surface treatment such as ZnNi plating has been applied to the contact surface portion.
JP 2004-197928 A JP 2004-197929 A JP 2005-308203 A

  However, it has been found that the surface treatment of the ZnNi plating as described above tends to generate corrosive organisms, and the extraction force of the extraction member increases due to the generation of the corrosive organisms. When the pulling force of the pulling member increases, torque blocking is not performed at the set torque value to be blocked, and the torque blocking performance of the power transmission device may be impaired. Such corrosive organisms are likely to be generated on the contact surface when, for example, salt water enters.

  Accordingly, the object of the present invention is to pay attention to the above problems, and the mechanism itself basically changes the generation of corrosive organisms at the contact surface between the drawing member and the member to which one end thereof is connected. Accordingly, an object of the present invention is to provide a power transmission device that can be suppressed only by simple and inexpensive processing, and that can suppress a rise in the cutoff torque and exhibit a stable torque cutoff performance.

  In order to solve the above problems, a power transmission device according to the present invention is provided between a driving side member and a driven side member, and is pulled out at the time of torque interruption, and one end side of the drawing member is connected to the driving side. In a power transmission device comprising a fastening member that is detachably fastened to a member or a driven side member when a transmission torque exceeds a set value, the contact surface of the driving side member or the driven side member to the drawing member is It consists of what was given the surface treatment which suppresses generation | occurrence | production of a corrosive organism.

  That is, corrosive organisms are likely to be generated on the contact surface of the drive side member or the driven side member to the extraction member, and when the corrosive organisms are generated, the extraction force of the extraction member increases, and the torque that is actually cut off thereby. Based on the knowledge that the value increases, the contact surface of the drive-side member or driven-side member where the corrosive organisms are likely to be generated is not a conventional ZnNi plating surface treatment but a special surface treatment that suppresses the generation of corrosive organisms. It is to give. This corrosive organism generation suppression surface treatment intentionally and actively suppresses the generation of corrosive organisms on this contact surface, thereby suppressing an increase in the extraction force of the extraction member due to the environment and environmental changes. Thus, the torque cutoff performance is maintained stably.

  Cationic electrodeposition coating is particularly suitable as the corrosive organism generation-suppressing surface treatment. In addition, as the surface treatment for inhibiting the generation of corrosive organisms, it is possible to coat with a fluorine resin, or coat with molybdenum disulfide and an organic binder. Which process is to be adopted may be determined in consideration of the shape and structure of the processing site and the degree and price of the processing effect, ease of processing, productivity of the entire apparatus, and the like.

  Further, in addition to the corrosive organism generation suppression surface treatment on the contact surface of the driving side member or the driven side member to the extraction member, the contact surface of the extraction member on the driving side member or the driven side member is the same as described above. The corrosive biogeneration-inhibiting surface treatment may be applied. By subjecting both contact surfaces to a surface treatment that inhibits the generation of corrosive organisms, the generation of corrosive organisms can be more reliably suppressed. In this case, the types of corrosive organism generation inhibiting surface treatments on both contact surfaces may be the same or different. When they are different, it is possible to employ a combination of various processes as described above.

  Although it does not specifically limit as said fastening member, For example, the rivet-shaped member which can be crimped can be used, and what is necessary is just to be able to crimp this rivet-shaped member in the axial direction. By using such a rivet-shaped member, it is possible to easily perform assembly and caulking.

  In the power transmission device according to the present invention, the drive side member or the driven side member is provided with a disk fixed to the member so as to be integrally rotatable, and one end side of the extraction member is fastened to the disk so as to be extracted. It is also possible to employ a structure in which at least the contact surface of the disc with the pull-out member is subjected to the corrosive organism generation suppressing surface treatment. The disk only needs to be tightly fixed to the corresponding rotating member by bolting or the like, and may be configured as an integral body with the rotating member. By providing such a disk, for example, it is possible to temporarily assemble as a pre-assembled part including the connection of the disk and the pull-out member via the fastening member. In this way, when the temporarily assembled assembly disk is assembled to the corresponding rotating member, predetermined assembly is completed, and assemblability is improved. Further, since the rivet-shaped member can be caulked at the assembly stage, the caulking force can be controlled more easily.

  The power transmission device according to the present invention is basically applicable as a power transmission device in any device, but in particular, there is a torque fluctuation in the drive source, and it is required to maintain a high-accuracy excessive transmission torque cutoff performance. It is effective in the case. For example, this is effective when the drive source of the drive side rotation member is a motor for a vehicle. In that case, it is particularly suitable as a power transmission device used for a compressor.

  As described above, according to the power transmission device according to the present invention, it is basically possible to perform a simple and inexpensive corrosive organism generation suppression surface treatment on a predetermined portion without requiring a design change of the device. The generation of corrosive organisms on the contact surface can be effectively suppressed, thereby suppressing an increase in the pulling force of the pulling member due to the environment and environmental changes, and the target torque interruption performance can be stably maintained.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
1A and 1B show a power transmission device according to a first embodiment of the present invention, in which FIG. 1A is a front view thereof, and FIG. 1B is a cross-sectional view taken along line BB in FIG. . In FIG. 1, 1 is a drive side member (drive side rotating member) composed of a pulley from which a driving force is transmitted via a belt or the like from a drive source such as an engine (not shown), and 2 is a drive of a compressor, for example. A driven side member (driven side rotating member) connected and fixed to a shaft or the like is shown, and these are arranged concentrically. The drive side rotating member 1 is supported via a bearing 3 so as to be rotatable with respect to the main body side of a compressor or the like. The driving side rotating member 1 and the driven side rotating member 2 are connected to each other via a pulling member 4 made of a flat plate member, and the torque from the driving side rotating member 1 is driven to the driven side rotating member 2 via the pulling member 4. To be communicated to.

  The driving side rotation member 1 and one end of the extraction member 4 are fixed by a first fastening member 5, and the driven side rotation member 2 and the other end of the extraction member 4 are fixed by a second fastening member 6. It is fixed. In this embodiment, when the torque from the driving side rotating member 1 is transmitted to the driven side rotating member 2 via the pulling member 4, the first fastening member 5 is pulled out when the transmission torque exceeds a set value. The torque transmission is interrupted by detaching from the member 4, that is, by pulling the pulling member 4 out of the fixed portion by the first fastening member 5 that has been fixed so far. It is also possible to cut off this torque transmission on the second fastening member 6 side. A fastening member configured to be able to be detached from the pull-out member 4 for blocking torque transmission, in the present embodiment, the first fastening member 5 is a columnar shape that is completely separate from the rotating members 1 and 2 and the pull-out member 4. It is comprised by the fastening member. In this embodiment, the fastening member 5 is composed of a rivet-like member having a head 8 having a diameter larger than that of the columnar shaft portion 7 on one end side of the columnar shaft portion 7 before mounting. By being caulked in the axial direction, the driving side rotating member 1 and the pulling member 4 are fixed via the fastening member 5 (9 indicates a caulking portion). In the present embodiment, a similar caulking fixing structure is also employed on the second fastening member 6 side that is not intended to be detached, but the fixing structure on this side is not particularly limited. However, the pulling member 4 is set to be rotatable around the second fastening member 6 when the pulling member 4 is pulled out from the fastening member 5 portion.

  In the present embodiment, the three extraction members 4 are arranged in the rotational direction (the direction of the arrow R in FIG. 1A), and each extraction member 4 is in the radial direction of the rotation members 1 and 2. The rotating member is arranged to be inclined in the rotation direction R. Each pull-out member 4 is formed with a hole 10 through which the columnar shaft portion 7 of the first fastening member 5 is inserted, and is connected to the hole 10 to open in the rotation direction R of the rotating member. A notch 11 is provided. Through the notch 11, the first fastening member 5 can be detached in the rotation direction R of the rotating member.

  2A and 2B show a power transmission device according to a second embodiment of the present invention, in which FIG. 2A is a front view thereof, and FIG. 2B is a cross-sectional view taken along line BB in FIG. . The second embodiment differs from the first embodiment shown in FIG. 1 only in that a disk (disk-shaped member) fixed to the one rotating member so as to rotate integrally therewith is provided. Since the other parts are basically the same as those in the first embodiment, the same members as those shown in FIG. 1 are denoted by the same reference numerals as those in FIG. In the structure shown in FIG. 2, a disk 21 is provided between the driving side rotating member 1 and the extraction member 4 so as to be rotatable integrally with the driving side rotating member 1, and the disk 21 is interposed via a fixing bolt 22. The drive-side rotating member 1 is fixed. Therefore, the drive side rotation member 1 and the disk 21 in FIG. 2 can be regarded as a drive side member (drive side rotation member) in the present invention. Note that reference numeral 23 in FIG. 2 denotes a hole formed in the drive side rotation member 1 in order to avoid interference with the crimped fastening member 5. By providing such a disk 21, as described above, for example, the disk 21 and the extraction member 4 can be assembled first via the fastening member 5, and the assembly is attached to the drive side rotating member 1 with a bolt. It becomes possible to conclude. As a result, the assembly can be facilitated, the control of the caulking force of the fastening member 5 can be facilitated, and the setting of the torque cutoff characteristics can be facilitated and the accuracy can be increased.

  FIG. 3 shows a cross-sectional structure after caulking by the fastening member 5 with respect to the embodiment shown in FIG. After the columnar shaft portion 7 of the fastening member 5 is inserted into the hole portion 10 of the extraction member 4 and the hole 24 formed in the disk 21, the end of the columnar shaft portion 7 opposite to the head portion 8 is caulked. The caulking portion 9 is formed by plastic deformation. In addition, it is preferable that the diameter of the hole 10 of the extraction member 4 and the hole 24 of the disk 21 is set to be slightly larger than the outer diameter of the columnar shaft portion 7, thereby facilitating insertion.

  When an excessive torque equal to or greater than the set transmission torque value is transmitted, the extraction member 4 is extracted from the fastening portion by the fastening member 5 as shown in FIG. 4, and the fastening member 5 is detached from the extraction member 4 and the disk 21 (drive) Side rotation member) idles and torque transmission is interrupted. In the present embodiment, as shown in FIG. 4, the shape of the tip portion 4 a branched into the forked portion of the extraction member 4 is an R shape in consideration of productivity and workability.

  A case where the surface treatment according to the present invention is applied to a device equivalent to the device shown in FIG. 2 in the power transmission device configured as described above will be described with reference to FIG. In the example shown in FIG. 5, a surface treatment that suppresses the generation of corrosive organisms is performed on the contact surface of the disk 21 serving as the drive-side member with the drawing member 4. Actually, a corrosive organism generation suppression surface treatment portion 31 is provided on the entire surface of the disk 21 on the contact surface side with respect to the extraction member 4.

  This corrosive organism generation suppression surface treatment is performed by, for example, cationic electrodeposition coating. However, as described above, in addition to the cationic electrodeposition coating, it is also possible to perform a corrosive organism generation-suppressing surface treatment by, for example, coating with a fluorine resin or coating with molybdenum disulfide and an organic binder. is there. In addition to the contact surface of the disk 21 as the drive side member, the contact surface of the extraction member 4 may be subjected to the same corrosive organism generation suppression surface treatment. In that case, the types of the corrosive organism generation inhibiting surface treatments on both contact surfaces may be the same or different.

  As described above, by providing the corrosive organism generation suppressing surface treatment portion 31 on the contact surface of the disk 21 with the extraction member 4, the generation of corrosive organisms is effectively suppressed, thereby the extraction member 4. The increase in the pulling force is suppressed, and the target torque interruption performance is stably maintained even in a severe environment or when there is an environmental change. Incidentally, as a result of conducting a forced durability test for 240 hours continuous operation in a salt spray environment, the contact surface of the disk 21 according to the present invention is compared with the case where the contact surface of the disk 21 is subjected to the conventional ZnNi plating surface treatment. When surface treatment for inhibiting the generation of corrosive organisms by cationic electrodeposition coating was performed, the generation of corrosive organisms such as red rust could be completely suppressed, and the effects of the present invention could be confirmed. In the test in which the contact surface of the disk 21 is subjected to cationic electrodeposition coating, when the contact surface of the extraction member 4 is stainless steel as a material base, the contact surface of the extraction member 4 is coated with molybdenum disulfide and an organic binder. In any case where the layer was provided, an excellent inhibitory effect on the generation of corrosive organisms was obtained.

  The power transmission device according to the present invention is basically applicable to a device that performs torque transmission in any device and blocks excessive transmission torque. In particular, it is suitable for torque transmission when there is a torque fluctuation in the drive source, for example, torque transmission using a vehicle prime mover as a drive source (for example, driving a compressor using a vehicle prime mover as a drive source). is there.

It is sectional drawing which follows the BB line of the front view (A) and figure (A) of the power transmission device which concerns on 1st embodiment of this invention. It is sectional drawing which follows the BB line of the front view (A) and figure (A) of the power transmission device which concerns on the 2nd embodiment of this invention. It is a fragmentary sectional view which shows an example of the crimping part by the fastening member of the apparatus of FIG. It is a partial front view which shows the state at the time of torque interruption of the apparatus shown in FIG. It is a schematic front view at the time of performing the surface treatment which concerns on this invention to the apparatus equivalent to the apparatus shown in FIG.

Explanation of symbols

1 Drive side member (Drive side rotating member)
2 Driven side member (driven side rotating member)
3 Bearing 4 Pull-out member 5 First fastening member (rivet-like member)
6 Second fastening member 7 Columnar shaft portion 8 Head portion 9 Caulking portion 10 Pull-out member hole portion 11 Notch 21 Disc 22 Fixing bolt 23 Hole formed in drive side rotating member Hole 31 formed in disc Corrosive Biogenesis control surface treatment part R Rotation direction

Claims (9)

  The pull-out member that is provided between the drive-side member and the driven-side member and is pulled out when the torque is interrupted, and one end of the pull-out member are pulled out when the torque transmitted to the drive-side or driven-side member exceeds the set value. In the power transmission device including a fastening member that can be fastened, the contact surface of the driving side member or the driven side member to the drawing member is subjected to a surface treatment that suppresses the generation of corrosive organisms. Power transmission device.   The power transmission device according to claim 1, wherein the corrosive organism generation-suppressing surface treatment is cationic electrodeposition coating.   The power transmission device according to claim 1, wherein the corrosive biogeneration-suppressing surface treatment is a coating of a fluororesin.   The power transmission device according to claim 1, wherein the corrosive biogeneration-suppressing surface treatment is a coating of molybdenum disulfide and an organic binder.   The power transmission device according to any one of claims 1 to 4, wherein the corrosive organism generation suppressing surface treatment is also applied to a contact surface of the pull-out member with respect to the driving side member or the driven side member.   The power transmission device according to claim 1, wherein the fastening member is a rivet-shaped member that can be caulked.   A disk fixed to the drive side member or the driven side member so as to rotate integrally with the member is provided, and one end side of the extraction member is fastened to the disk so as to be extractable, and at least to the extraction member of the disk The power transmission device according to claim 1, wherein the contact surface is subjected to the surface treatment for inhibiting the generation of corrosive organisms.   The power transmission device according to any one of claims 1 to 7, wherein a drive source of the drive side member is a vehicle prime mover.   The power transmission device according to any one of claims 1 to 8, which is used for a compressor.

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