JPS6392826A - Coupling mechanism - Google Patents

Abstract

PURPOSE:To control the displacement velocity of a piston with a simple structure, by introducing an oil pressure on the head part of a piston inside a piston cover, and providing grooves for releasing the oil pressure on the head part, when the piston is displaced by a prescribed distance, in the position opposite to the side surface of the piston. CONSTITUTION:In the interior of a clutch housing 201, a piston cover 202 which is fixed to a shaft 100 is arranged, and inside the piston cover a piston 204 is inserted, so that the input side friction plates 208 of a slider 206 integrally turning with the shaft 100 are operated so as to be pressed on output side friction plates 207. Further, on the piston cover 202, releasing grooves 205 through which the pressure in the pressure chamber 280 at the piston head part is released to the rear surface side are formed. Accordingly, with a simple constitution, the displacement velocity of the piston 204 can be controlled so that it is fast at the time of starting of coupling, and that it is gradual after the clearances between friction plates 207 and 208 have become small.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a rotational force coupling mechanism, for example, for introducing or not introducing rotational force from an automobile engine into a refrigerant compressor for an automobile air conditioner. It is effective when used.

[Prior art and its problems]

2. Description of the Related Art Conventionally, a coupling mechanism is known in which a piston is moved by fluid pressure such as oil pressure, a friction plate is displaced by the piston, and rotational torque is transmitted by pressing the friction plates together. When such a transmission mechanism is used, for example, to transmit power to a compressor for an automobile air conditioner, it is effective in reducing the shock at the time of connection, and for this purpose, the movement of the piston at the time of connection is It is preferable to move quickly at the beginning of the movement, and to move slowly after the friction plates begin to come into contact with each other.

Conventionally, the displacement speed of the friction plate has been adjusted by controlling the switching of the oil introduced (see, for example, Japanese Patent Laid-Open No. 58-211025).

However, if a switching piston or the like is used in this way, the hydraulic circuit becomes complicated, and the entire coupling mechanism has to be enlarged.

[Problem that the invention seeks to solve]

The present invention was devised in view of the above points, and its purpose is to make the movement of a piston that displaces a friction plate quick at the beginning of the movement, and to move slowly after the friction plate comes into contact with the piston. A further object of the present invention is to achieve such movement of the piston with an extremely simple configuration.

[Configuration and operation]

In order to achieve the above object, in the present invention, a piston is slidably disposed within a piston cover attached around a shaft, and pressure from a hydraulic pump is guided to the head of the piston. Further, a relief groove is provided in a position of the piston cover facing the side surface of the piston to release hydraulic pressure from the piston head to a low pressure region when the piston is displaced by a predetermined amount.

With the above configuration, when hydraulic pressure is introduced to the piston head, the piston is quickly displaced in response to the hydraulic pressure. When the piston is displaced a predetermined distance and the relief groove formed on the inner surface of the piston cover opens to the piston head, the hydraulic pressure in the piston head is released through the relief groove. Since the hydraulic pressure is thus released through the relief groove, the displacement speed of the piston is reduced.

〔Example〕

An embodiment of the coupling mechanism of the present invention will be described below with reference to the drawings. In Fig. 1, 100 is a shaft, and this shaft is the hub 5.
03 with bolts 504. Further, the hub 503 is coupled to a pulley 500, and the hub 503 is connected to a pulley 500.
rotates by receiving the rotational force of an automobile engine (not shown) via a V-belt (not shown). Therefore shaft 10
0 rotates together with pulley 500. In addition, pulley 500
is rotatably supported by a bearing 502.

The bearing 502 is fixed on the front cover 501, and a shaft seal 505 is provided on the inner surface of the front cover 501 to provide a seal between the front cover 501 and the shaft.

The pump housing 30 is attached to the side of the front cover 501.
4 is disposed, and a trochoid pump 300 is disposed within this pump housing 304. The trochoid pump 300 sucks oil in an oil reservoir 303 through a suction passage 301, raises the pressure to a predetermined pressure, and then leads it out to the discharge passage 302 or the oil guide passage 230 side.

The trochoid pump 300 is fixed to the outer periphery of the shaft 100, and receives the rotational force of the shaft 1000 to operate the pump. The discharge passage 302 is a solenoid valve 4
It is connected to the oil reservoir 303 via 00. That is, when the solenoid valve 400 is open, the discharge passage 3
02 opens to the oil reservoir 303, and therefore almost all of the oil discharged from the trochoid pump 300 is returned to the oil reservoir 303 side. Conversely, the solenoid valve 40
0 is closed, the discharge passage 302 is closed, and the oil discharged from the trochoid pump 300 flows to the oil receptacle 230 side.

A clutch housing 201 is disposed on a side surface of the pump housing 304. This clutch housing 20
1 has a cylindrical space inside, and a piston cover 202 is disposed within this space. Piston cover 20
2 is fixed to the outer periphery of the shaft 100, and the shaft 1
It rotates together with 00. Piston cover 202
A bearing 211 is located between the side surface of the pump housing 304 and the pump housing 304.
is provided to support the load of the piston cover 202 in the thrust direction.

A ring-shaped space is formed in the piston cover 202, and a piston 204, which is also ring-shaped, is placed in this space.
are slidably arranged. A slider 206 is disposed on the outer periphery of the shaft 100 so as to rotate together with the shaft 100. Furthermore, the displacement of the slider 206 in its axial direction is also restricted by a circlip 240. Further, a spring 203 is disposed between the slider 206 and the piston 204, and this spring 203 is disposed between the slider 206 and the piston 204.
03, the piston 204 is pressed against the piston cover 202.

The oil guide passage 230 described above is formed in the shirt 100, and the oil guide passage 230 is also supplied to the head of the piston 204 from the oil guide passage 230 formed in the piston cover. A relief groove 205 is cut out in the piston cover 202 at a position facing the side surface of the piston 204. This relief groove 205 is the piston 20
4 is displaced by a predetermined amount, it opens into the pressure chamber 280 of the piston head.

An input side friction plate 208 is disposed on the outer periphery of the slider 206 so as to be displaceable in the axial direction. A plurality of friction plates 208 are provided on the input side, and a spacer 2 is provided between each friction plate 208.
41 are arranged.

An output side friction plate 207 is arranged adjacent to the input side friction plate 208 . This output side friction plate is fixed to an output rotating body 209, and the output rotating body 209 is fixed to an output shaft 215. A bearing 212 is disposed within the output shaft 215, and the distal end of the shaft 100 is rotatably supported by the bearing 212. Further, the output shaft is rotatably supported by the side plate 104 via a bearing 112. Further, a bearing 210 is disposed between the side plate 104 and the side surface of the output rotary body 209, and the thrust direction load of the output rotary body 209 is supported by this bearing.

The output shaft 215 is integrally formed with the rotor 102, and therefore the rotor 102 rotates within the pump housing 101 under the rotational force of the output shaft. The rotor 102 has a vane 1
03 is slidably disposed, and as the rotor 1020 rotates, the volume of the pressure chamber formed by the vane 103, the rotor 102, and the pump housing 101 changes. A suction hole (not shown) is opened in the front side plate 104, and refrigerant is sucked into the pressure chamber through this suction hole.

Further, the refrigerant compressed in the pressure chamber is discharged into the discharge chamber 107 from a discharge hole (not shown). The high-pressure refrigerant discharged into the discharge chamber 107 is discharged into the oil separation chamber 151 in the rear cover 109 via the discharge passage 108. The lubricating oil is separated in the separation chamber 151, and the refrigerant is then discharged to the unillustrated condenser side of the refrigeration cycle. Further, the lubricating oil separated in the separation chamber 151 is stored in the oil reservoir chamber 110. Note that the above-mentioned pump housing 304. clutch housing 201,
Front side plate 104. pump housing 10
1. Rear side plate 105 and rear cover 109
are integrally connected by a through bolt 152. A minute gap is formed on the outer periphery of the through bolt 152, and the lubricating oil stored in the oil reservoir chamber 110 is supplied to the oil reservoir 303 side through this gap. 153 is this supply passage.

Next, the operation of the coupling mechanism having the above configuration will be explained.

The pulley 500 is constantly rotated by the rotational force of the automobile engine. Therefore, this rotation is received by the shaft 10.
0 is also constantly rotating, and the trochoid pump is constantly discharging oil. When the compressor does not require rotational force, the solenoid valve 400 is open. Therefore, the entire amount of oil discharged from the trochoid pump 300 is returned to the oil reservoir 303 side. That is, in this state, the trochoid pump 300 operates without load.

When it is necessary to transmit rotational force to the compressor side, the solenoid valve closes the discharge passage 302 upon receiving an electric signal. As a result, the oil discharged from the trochoid pump 300 is supplied from the oil guide passage 230 to the pressure chamber 280 side. As lubricating oil is supplied to the pressure chamber, the piston 204 is displaced to the right in FIG. This displacement is the slider 20
6, the input side friction plate 208 disposed on the outer periphery is displaced to the right in the figure. Here, a plurality of input side friction plates 2
08 are connected via the spacer 241, the displacement of the piston 204 is transmitted almost equally to all the friction plates 208. As a result, the gap between the input-side friction plate 208 and the output-side friction plate 207 is reduced in such a manner that almost all the friction plates are uniform.

As the gap between the input side and output side friction plates 208, 207 becomes smaller, the frictional force between both the friction plates 208, 207 increases. As a result, the rotational force of the slider 206 is transmitted to the output rotating body 209 side. here,
Since the slider 206 rotates integrally with the shaft 100 and the output rotating body 209 is fixed to the output shaft 215, the rotational force of the shaft 100 is transmitted to the output shaft 215 side by the frictional force of the friction plate.

Since a relief groove 205 is formed in the piston cover 202, once the piston 204 is displaced to a predetermined position,
The pressure within the pressure chamber 280 will be released to the back side of the piston 204. Here, clutch housing 201
A suction passage is open to the refrigeration cycle, and low-pressure refrigerant is supplied from an evaporator (not shown) of the refrigeration cycle. That is, the inside of the clutch housing 201 also serves as the suction chamber 150. And the pressure in the suction chamber is
Since the pressure is lower than the pressure of the oil discharged from the trochoid pump 300, if the relief groove 205 is opened, the oil will escape from the pressure chamber 280 to the suction chamber 150 side.

That is, after the relief groove 205 is opened, the pressure chamber 28
0 pressure increase rate becomes smaller. Here, the relief groove 205
is extremely small, and its current 1ffi resistance is large. Therefore, no matter how much the relief groove 205 is opened, a predetermined pressure is still maintained in the pressure chamber 280, and this pressure pushes the input side friction Fi 208 toward the output side friction plate 207. However, the displacement speed decreases as the relief groove 205 opens.

The output shaft 215 receives the rotational force via the friction plates 208 and 207.
When the rotor lOO rotates, the rotor lOO also rotates together. As the rotor rotates, the refrigerant in the suction chamber 150 is supplied from a suction hole formed in the front side plate 104 to a pressure chamber formed on the rotor 102 side. The refrigerant sucked in as the volume of the pressure chamber fluctuates is compressed, and when it reaches a predetermined value, it is discharged from the discharge hole into the discharge chamber 107. After the oil is separated in the oil separation chamber, it is discharged to the condenser side of the refrigeration cycle (not shown).

Note that FIGS. 2 and 3 show the displacement state of the piston 204, and show that the relief groove 205 opens to the pressure chamber 280 as the gap between the friction plates 207 and 208 becomes smaller, as described above. . Also, as shown in the figure, piston 2
An O-ring 256 is disposed around the outer periphery of the piston 204 to maintain a seal between the piston 204 and the piston cover 202.

As described above, in the compressor of the present invention, the displacement speed of the piston 204 can be controlled by the extremely simple configuration of providing the relief groove in the piston cover 202. That is, in the coupling mechanism of the present invention, the piston 204 is rapidly displaced at the start of coupling, and after the gap between the friction plates is reduced, the displacement speed of the piston can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing one embodiment of the coupling mechanism of the present invention, and FIG.
This figure and FIG. 3 are cross-sectional views showing the operating state of the coupling mechanism shown in FIG. 1. 100... Shaft, 201... Clutch housing, 202... Piston cover, 204... Piston. 205... Relief groove, 280... Pressure chamber, 300...
... Trochoid pump, 301 ... Suction passage, 302
...Discharge passage, 230... Oil guide passage, 400...
Solenoid valve, 500...Pulley.

Claims (1)

[Claims] A shaft that rotates by receiving rotational force from a pulley, and an oil pump that operates by receiving rotational force from this shaft.
A clutch housing disposed to cover the shaft, a piston cover disposed within the clutch housing, a piston slidably disposed within the piston cover, and a piston disposed on the shaft. A slider that rotates integrally with the shaft, an input friction plate disposed on the slider, an output friction plate placed opposite the input friction plate, and an output rotation to which the output friction plate is fixed. an oil guide passage that guides discharge oil from the trochoid pump to the end surface of the piston, a control valve that controls the discharge oil pressure of the trochoid pump, and a control valve that is formed in the piston cover so that the piston is connected to the input side friction. A coupling mechanism characterized by having a relief groove that allows oil guided to the end of the piston to escape when the plate is displaced a predetermined distance in the direction of the output side friction plate.