JP2003322173A - Power transmission device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power transmission device capable of being assembled without impairing the shearing performance of a shear pin. <P>SOLUTION: A strike plate 20 receiving a press-fit load at its one end side by a notch 16 of the shear pin 15 is mounted. The shear pin 15 can be press- fitted and fixed without adding the press-fit load to the notch 16 of the shear pin 15. Whereby assembling can be performed without impairing the shearing performance of the notch 16 of the shear pin 15. <P>COPYRIGHT: (C)2004,JPO

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle air conditioner, etc.
The present invention relates to a power transmission device attached to an auxiliary device for a vehicle. 2. Description of the Related Art Some conventional power transmission devices include, for example,
The one shown in Japanese Utility Model Laid-Open No. 1-169619 has been proposed. In this power transmission device, a power transmission member and a driven power transmission member integrally mounted on a rotating shaft of an auxiliary machine are connected by a plurality of shear pins, and when an auxiliary machine is overloaded, a fragile portion of the shear pin is provided. Is prevented from hindering the operation of other associated auxiliary machines. [0003] However, if an overload is applied to the fragile portion (shear portion) of the shear pin in the assembling process of the power transmission device and the fragile portion is damaged and deteriorated, the set shear torque is set. In the following, the shear pin is sheared, which may adversely affect the shearing performance. SUMMARY OF THE INVENTION The present invention has been made in view of such a background art, and an object of the present invention is to provide a power transmission device that can be reliably and easily assembled without reducing the shearing performance of a shear pin. According to the present invention, a power transmission member is rotatably mounted on a housing of an auxiliary machine for a vehicle concentrically with a rotating shaft of the auxiliary machine. And a power transmission member fixed to the rotation shaft and disposed opposite to the power transmission member in the axial direction of the rotation shaft; and a weak portion between the opposing surfaces of the power transmission member and the power transmission member. And a plurality of shear pins for connecting the power transmission member and the power transmission member. A shear pin for press-fitting one end of the shear pin to one of the power transmission member and the power transmission member to fix the shear pin. A press-fit hole is formed, and the other end of the shear pin is formed with a shear pin insertion hole for inserting the other end of the shear pin, and the other end and the one are fastened and fixed using a projecting end portion of the shear pin projecting from the other shear pin insertion hole. You In the power transmission device, the shear pin includes a seat for receiving a press-fit load at a position where stress is not applied to the fragile portion. According to the first aspect of the present invention, since the shear pin is provided with a seat for receiving a press-fit load at a position where stress is not applied to the fragile portion, the shear pin is pressed when the shear pin is pressed. No stress is applied to the shear pin, and it is possible to avoid a decrease in the shearing performance of the shear pin. Further, since no stress is applied to the fragile portion as described above, the shear pin can be press-fitted with a larger press-fit than before. In other words, it is possible to set the shear pin press-fitting and fixing allowance larger than in the conventional case, and to more securely fix the shear pin. Thereby, even if the driven power transmission member and / or the power transmission member is bent and the driven power transmission member and the power transmission member are fastened and fixed by the shear pin, there is no fear that the shear pin will fall off due to the bending restoring force. . Therefore, even if the dimensional errors in the axial direction of the vehicle accessory, the driven power transmission member, and the power transmission member are set relatively broadly, the dimensional variation is allowed by bending the driven power transmission member and / or the power transmission member. Manufacturing costs can be greatly reduced. In the present invention, the fastening system between the power transmission member and the power transmission member using the projecting end of the shear pin may be any of a caulking system and a bolt-nut system. An embodiment of the present invention will be described below with reference to the drawings. First Embodiment FIGS. 1 to 7 show a first embodiment of the present invention.
1 shows a power transmission device of an embodiment. The power transmission device of this embodiment is a power transmission device of a compressor (vehicle accessory) interposed in a refrigeration cycle of a vehicle air conditioner. FIG. 1 shows a part of the power transmission device of this embodiment. FIG. 2 is a front view of the power transmission device, FIG. 3 is a side view and a top view of a shear pin used in the power transmission device, and FIGS. Figure,
FIG. 7 is a view showing a step of press-fitting the shear pin into the press-fit hole. The housing of the compressor is not shown in FIG. As shown in FIGS. 1 and 2, "vehicle auxiliary equipment"
One end of a housing 1 of a compressor as a “powered transmission member” to which driving force from a power source is transmitted through a belt (not shown) concentrically with a rotating shaft 2 of the compressor. The pulley 3 is rotatably mounted via a bearing member 24 which has been press-fitted and attached to the inner periphery thereof in advance. A drive plate 4 as a “power transmission member” is attached to an end of the rotating shaft 2, and the drive plate 4 is arranged to face one side of the pulley 3. The drive plate 4 has a first plate 5 fixed to the end of the rotating shaft 2, and a second plate 5 disposed on the outer peripheral side of the first plate 5 and connected to the first plate 5 via a damper rubber 7. And a plate 6. The damper rubber 7 is vulcanized and bonded to a flange edge 5a bent on the outer periphery of the first plate 5 and a flange edge 6a bent on the inner periphery of the second plate 6. A bolt insertion hole 8 is formed in the center of the first plate 5, and a plurality of boss members 9 (three in this example) are formed concentrically with the bolt insertion hole 8 on the side surface facing the housing 1. The rivet pin 10 is fixed to the end of the rotating shaft 2 of the boss member 9 by a spline engaging means 11 in a non-rotating manner, and a screw provided at the end of the rotating shaft 2 through the bolt insertion hole 8. It is screwed and fastened to the hole 12 with a bolt 13. The second plate 6 and the pulley 3
Are connected via a plurality (three in this example) of shear pins 15. The shear pin 15 has a notch 16 as a "fragile portion" disposed between the opposing surfaces of the pulley 3 and the second plate 6, for example, when the rotation of the rotary shaft 2 stops due to a failure of the compressor. The purpose of the present invention is to prevent the notch 16 from shearing and hindering the rotation of the engine linked to the compressor and the operation of other accessories. The connection between the second plate 6 and the pulley 3 by the shear pin 15 is performed by connecting the press-fit portion 17 forming one end of the shear pin 15 to the shear pin press-fit hole 2 provided in the pulley 3.
1, and the other end of the shear pin 15 is inserted through a shear pin insertion hole 22 provided in the second plate 6,
A nut 23 is screwed into a screw portion 18 formed at the projecting end of the shear pin 15 projecting from the shear pin insertion hole 22 to connect the second plate 6 and the pulley 3. A flange 19 forming a base end of the screw portion 18 is formed near the second plate 6 of the notch 16, and a minimum diameter portion of the notch 16 is located at a forming base of the flange 19. . The present invention is characterized in that a receiving seat 20 for receiving a shear pin press-fitting load is provided at one end of the notch 16 of the shear pin 15 from the notch 16, that is, at the press-fitting portion 17, and in this embodiment, FIG. As shown, the press-fit portion 17
Is set to have a diameter larger than that of the flange 19, so that a part of the base end face of the press-fitting portion 17 is configured as a receiving seat 20 that receives a shear pin press-fitting load from the jig 30. Now, an assembling process of the power transmission device will be described with reference to FIG. 1 and FIGS. First, as shown in FIG. 4, the press-fit portion 17 of the shear pin 15 is press-fitted and fixed in the shear pin press-fit hole 21 of the pulley 3. More specifically, as shown in FIG. 7A to FIG. 7B, a press-fit load is applied to the receiving seat 20 while supporting the flange 19 of the shear pin 15 with the cylindrical jig 30, and the press-fit portion 17 of the shear pin 15 is inserted into the shear pin press-fit hole. 21 and press fit. In addition, the support of the shear pin 15 by the jig 30 may be performed at a portion other than the flange 19, or a method of generating an electromagnetic force on the jig 30 and supporting it by suction may be used. The pulley 3 on which the shear pin 15 is fixed as described above is connected to the compressor housing 1 as shown in FIG.
Is rotatably mounted to one end of the first through a bearing member 24. In order to connect the pulley 3 and the rotary shaft 2 of the compressor with a drive plate 4, first, FIG.
As shown in (1), the first plate 5 of the drive plate 4 is fixed to the end of the rotating shaft 2 of the compressor with bolts 13. At this time, the gap d = the gap between the second plate 6 of the drive plate 4 and the flange 19 of the shear pin 15 to allow a total value ± α of the dimensional error and the assembly error of the compressor 2, the pulley 3 and the drive plate 6. d ₀ ± α> 0 is generated. The interval d ₀ is a design value set in advance to allow the error α. Finally, a nut 23 is screwed into the threaded portion 18 of the shear pin 15, and the pulley 3 and the drive plate 4 are fastened via the shear pin 15, as shown in FIG. Complete. At this time, the drive plate 4 is fastened in a bent state. According to the power transmission device of the first embodiment, since the receiving seat 20 for receiving the press-fitting load is provided at a portion on one end side of the notch 16 of the shear pin 15, that is, the press-fitting portion 17, the notch 16 The press-fit load is not applied, and it is possible to reliably prevent the shearing performance of the shear pin 15 from being lowered. According to the power transmission device of the first embodiment, since no stress is applied to the notch 16 as described above, in order to securely fix the shear pin 15, a larger press-in allowance for the shear pin is set than in the prior art. The shear pin 15 can be press-fitted with a large press-fit. For this reason, conventionally, in order to reduce the manufacturing cost, the axial dimension accuracy of the compressor housing, the pulley, and the drive plate is set low (roughly) and the drive plate is largely bent, and the pulley and the drive plate are sheared with the shear pin. In the case of the structure of fastening and fixing, there was a concern that the shear pin would fall out of the shear pin press-in hole due to the large deflection restoring force, but in the present embodiment, the shear pin 15 is dropped by setting a large press-in allowance for the shear pin 15. No worries.
As a result, the axial dimensional accuracy of the compressor housing 1, the pulley 3, and the drive plate 4 can be set low (roughly), and the manufacturing cost of each component can be reduced accordingly. Also, the assembly cost can be reduced. Further, according to the power transmission device of the first embodiment, when the notch 16 of the shear pin 15 is sheared, the drive plate 4 is separated from the side surface of the pulley 3 by the bending restoring force of the drive plate 4, and the shear pin Fifteen
The sheared portion of the pulley 3 does not interfere with the side of the pulley 3
Can surely run idle. Further, according to the power transmission device of the first embodiment, the minimum diameter portion of the notch 16 formed at the base where the flange 19 of the shear pin 15 is formed is adjusted to the reference surface (the pulley 3).
(The front end surface of the pulley 3 = the surface facing the drive plate 3 of the pulley 3), which is a preferable structure from the viewpoint of shearing the shear pin 15. In the present invention, the minimum diameter portion of the notch 16 does not need to coincide with the reference plane, and a portion on one end side of the notch 16, for example, the shear pin 15
However, the seat 20 may coincide with the reference plane. Second Embodiment FIGS. 8 and 9 show a power transmission device according to a second embodiment. Note that the same components as those in the above embodiment are denoted by the same reference numerals, and description thereof is omitted. The power transmission device according to the second embodiment has a structure in which the flange 41 of the shear pin 40 can be held between the pulley 3, the drive plate 4 and the facing surface.
The basic structure of the shear pin 40 differs from that of the first embodiment in that the flange 41 is set to have a larger diameter than the press-fit portion 17. In the second embodiment, in such a basic structure, notches 42, 42 are provided in the flange 41 so that a part of the base end face of the press-fit portion 17 of the shear pin 40 can be partially pressed into the press-fit load of the flange 41. This is an example in which the exposed portion is exposed outside the direction projection plane, and the exposed portion is configured as a seat 43 for receiving a press-fit load. As described above, the power transmission device of the second embodiment also includes the receiving seat 43 for receiving a press-fit load at a portion on one end side of the notch 16, that is, the press-fit portion 17, so that the same operation as the first embodiment is performed. The effect can be obtained. According to the power transmission device of the second embodiment, since the shear pin 40 has the flange 41 sandwiched between the opposing surfaces of the drive plate 4 and the pulley 3, first, the notch is formed by the flange 41. 16 is extremely easy to position. Secondly, even if the pulley 3 and the drive port 4 are strongly fastened and fixed, a gap corresponding to the thickness of the flange 41 is formed between the two members 3 and 4, so that both members 3 , 4 is more reliably subjected to a predetermined shearing force. Third, when the nut 23 is tightened, the flange 41 is sandwiched between the opposing surfaces of the pulley 3 and the drive plate 4, so that the screw portion 18 including the flange 41 is closer than the structure in which the flange is not clamped. Is difficult to rotate with the fastening torque of the nut 23. Therefore, even if the nut is tightened with a relatively strong force, a structure in which the fastening torque is not easily applied to the notch 16 is obtained. Further, according to the power transmission device of the second embodiment, since the notch 42 is provided in the flange 41 of the shear pin 40, even if the outer diameter of the press-fit portion 17 is relatively small, the press-fit is not required. The portion 17 has an advantage that the receiving seat 43 can be formed. As the outer diameter of the press-fit portion 17 is reduced,
The weight of the shear pin 40 can be reduced, and the degree of freedom in the layout of the shear pin press-fit hole 21 can be increased. Third Embodiment FIGS. 10 to 12 show a power transmission device according to a third embodiment of the present invention.
In the first and second embodiments described above, the screw 1
Since the outer diameter or shape of the flanges 19 and 41 is devised, the receiving seats 20 and 43 are formed in the press-fitting portion 17 because the outer diameter or the shape of the flanges 19 and 41 is modified.
As shown in FIGS. 10 to 12, the outer diameter of the screw portion 18 ≧ the press-fit portion 5
In a shear pin structure or the like that satisfies one outer diameter, the protrusions 53, 53 projecting from the press-fitting portion 51 and extending at least outward from the flange 52 are configured as “receiving seats”, and the pulleys 3 receive the protrusions 53, 53. By providing the grooves 54, 54, the same effect as in the first and second embodiments can be obtained. In this case, the flange 52 constituting the base end of the screw portion 18 has a structure sandwiched between the pulley 3 and the drive plate 4, so that the same operation and effect as the flange 41 of the second embodiment can be obtained. Demonstrate. The shape of the flange 52 is, for example, a circle as shown in FIG.
For example, a square as shown in FIG. here,
Reference numeral 55 in FIGS. 10 and 11 indicates a shear pin press-fit hole. As described above in the first to third embodiments, according to the present invention, the receiving pin for receiving the press-fit load is provided at one end (press-fit portion) from the weak portion (notch) of the shear pin. The shear pin can be press-fitted and fixed without applying a press-fit load to the fragile portion. Therefore, it becomes possible to assemble without reducing the shearing performance of the fragile portion of the shear pin. In any of the above-described embodiments, the flanges 19, 41,
Although this is an example in which the present invention is applied to a shear pin structure including the pin 52, the technical idea of the present invention can be applied to a shear pin without a flange. In the above embodiment, the pulley and the drive plate are fastened and fixed by screwing a nut to the projecting end of the shear pin. The structure which fastens and fixes with a drive plate may be sufficient. Further, the present invention includes the following shear pin press-fitting fixing structure as a modified example in which the shear pin 15 of the first embodiment is applied. Referring to FIGS. 1 and 4 of the first embodiment, the structure is a structure in which the shear pin 15 is press-fitted into the shear pin press-fit hole 21 from the compressor housing 1 side. In other words, it is based on the fact that the shear pin 15 is configured such that the thread part 18 outer diameter <the flange 19 outer diameter <the press fitting part 51 outer diameter, and the rear end face of the shear pin 15 is the “receptacle” of the present invention. is there. When the shear pin is press-fitted and fixed in this manner, a press-fit load is not applied to the notch 16, and a reduction in the shearing performance of the shear pin 15 can be reliably avoided. In this case, the pulley 3 is designed to have a structure in which the shear pin press-fitting hole 21 is formed completely through the compressor housing 1 with the same diameter so that the shear pin 15 can be pressed into the shear pin press-fitting hole 21 from the compressor housing 1 side. There is a need to.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view of a power transmission device for a vehicle accessory according to a first embodiment, including a broken portion of a main part. FIG. 2 is a front view of the power transmission device. FIG. 3 is a view showing a shear pin used in the power transmission device, wherein FIG. 3A is a top view of the shear pin, and FIG. 3B is a side view of the shear pin. FIG. 4 is an explanatory view of an assembling process of the power transmission device. FIG. 5 is an explanatory diagram of an assembling process of the power transmission device. FIG. 6 is an explanatory diagram of an assembling process of the power transmission device. FIG. 7 is a diagram showing a step of press-fitting a shear pin into a shear pin press-fitting hole. FIG. 8 is a fragmentary cross-sectional view of a power transmission device for a vehicle accessory according to a second embodiment. 9 is a view showing a shear pin used in the power transmission device, wherein FIG. 9A is a side view of the shear pin, and FIG. 9B is a top view of the shear pin. FIG. 10 is a fragmentary cross-sectional view of a power transmission device for a vehicle accessory according to a third embodiment; 11 is a view as viewed in the direction A in FIG. 10 and shows a state before the drive plate is assembled. FIG. 12 is a view showing a shear pin according to a third embodiment, in which a separation diagram b is a top view of the shear pin, a separation diagram a and a separation diagram c.
Is a side view of one of the shear pins. FIG. 13 is a top view of the shear pin, showing a modification of the flange of the shear pin. FIG. 14 is a view showing a modified example of a flange of a shear pin, wherein a separation diagram b is a top view of the shear pin, and separation diagrams a and c are side views of the shear pin. [Description of Signs] 1 Compressor housing (vehicle accessory housing) 2 Rotary shaft 3 Pulley (power-transmitted member) 4 Drive plate (power-transmitting member) 15 Sharpin 16 Notch (fragile portion) 17 Press-fit portion (Sherpin) 18 Threaded portion (protruding end) 19 Flange 20 Receptacle 21 Sherpin press-in hole 22 Sherpin insertion hole 23 Nut 40 Sherpin 41 Flange 43 Receipt 50 Sherpin 51 Press-fit portion One end side part) 52 Flange 53 Projection (seat) 55 Sherpin press-fit hole

Claims (1)

Claims: 1. A power transmission member (3) mounted on a housing (1) of a vehicle auxiliary machine so as to be rotatable concentrically with a rotation shaft (2) of the auxiliary machine, and A power transmission member (4) fixed to a rotating shaft (2) and arranged to face the power transmission member (3) in the axial direction of the rotation shaft (2); and the power transmission member (3). A weak portion (16) is arranged between the opposing surfaces of the power transmission member (4), and a plurality of shear pins (15, 40, 40) connecting the driven power transmission member (3) and the power transmission member (4). 50), and a shear pin press-fit hole (21, 55) for press-fitting and fixing one end side of the shear pin (15) to one of the power transmission member (3) and the power transmission member (4), and the other end. Forming a shear pin insertion hole (22) through which the other end of the shear pin (15) is inserted A power transmission device for fastening and fixing the other and the one by using a projecting end of a shear pin (15) protruding from the other shear pin insertion hole (22), wherein the shear pins (15, 40, 50) And a receiving seat (20, 43, 53) for receiving a press-fit load at a position where stress is not applied to the fragile portion (16).