JP2000310253A - Fluid joint device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent pressure rise in a fluid joint due to thermal expansion of an operating fluid by arranging a fluid storage tank storing the operating fluid at a position higher than an output shaft, and communicating the fluid storage tank with an operation chamber formed of a pump and a turbine. SOLUTION: A fluid storage tank 60 storing an operating fluid is arranged at a position higher than an output shaft 46 fitted with a turbine 43 of a fluid joint. The fluid storage space 61 of the fluid storage tank 60 is communicated with an operation chamber 40a formed of a pump 42 and a turbine 43 via a communication path 67, a passage 462, a passage 461 and a chamber 40a formed of a casing 41 and the pump 42. Even when the operating fluid is heated and thermally expanded while circulating, the thermally expanded quantity can be absorbed by the storage space 61. The pressure increased by absorbing the thermally expanded quantity of the operating fluid is released to the atmosphere via an air breather 65, and pressure rise due to the thermal expansion of the operating fluid can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid coupling (fluid coupling) for transmitting rotational torque of a motor.
It relates to improvement of the device.

[0002]

2. Description of the Related Art Fluid coupling devices have been conventionally used as power transmission couplings for ships, industrial machines, and automobiles. A vehicle drive device equipped with a fluid coupling is disclosed in, for example, Japanese Patent Application Laid-Open No. 55-159360. The fluid coupling disclosed in the publication includes a pump connected to a crankshaft (an input shaft as a fluid coupling) of an engine, and an output arranged on the same axis as an input shaft disposed to face the pump. A working fluid is sealed in a working chamber formed by the pump and the turbine. Such a hydraulic fluid-filled type fluid coupling has a simple structure because the hydraulic fluid is sealed inside the fluid coupling so that the hydraulic fluid does not leak to the outside and no oil seal is required. Become.

[0003]

The working fluid sealed in the fluid coupling generates heat by circulating in the fluid coupling and expands thermally. Therefore, the above-mentioned fluid coupling in which the working fluid is sealed cannot absorb the thermal expansion of the working fluid because the working fluid is sealed. Therefore, since the pressure inside the fluid coupling becomes extremely high, there is a problem that the fatigue fracture of the fluid coupling is induced and the drag torque, that is, the transmission torque when the engine is operated at the idling speed increases.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and a main technical problem thereof is to provide a fluid coupling device capable of preventing an increase in pressure inside a fluid coupling due to thermal expansion of a working fluid. .

[0005]

According to the present invention, in order to solve the above-mentioned main technical problems, a pump mounted on an input shaft and a pump disposed opposite to the pump and coaxial with the input shaft are provided. And a turbine attached to an output shaft disposed on a line, wherein a fluid storage tank containing a working fluid is disposed at a position higher than the output shaft, and the fluid storage tank is connected to the pump by the pump. And a fluid coupling device communicating with a working chamber formed by the turbine and the turbine.

It is desirable that an air breather is mounted on the fluid storage tank.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a fluid coupling device constructed in accordance with the present invention will be described below in more detail with reference to the accompanying drawings.

FIG. 1 shows an embodiment of a drive device in which a fluid coupling (fluid coupling) device to which the present invention is applied is disposed between an automobile engine and a friction clutch. The drive device in the illustrated embodiment includes an internal combustion engine 2 as a prime mover, a fluid coupling device 4 and a friction clutch 8 configured according to the present invention. The internal combustion engine 2 is a diesel engine in the illustrated embodiment, and a pump side, described later, of the fluid coupling device 4 is attached to an end of the crankshaft 21.

The fluid coupling device 4 includes a diesel engine 2
Is provided in the fluid coupling housing 6 which is attached to the housing 22 mounted on the housing 22 by fastening means such as bolts 23. Fluid coupling device 4 in illustrated embodiment
Is provided with a fluid coupling 40 having a casing 41, a pump 42 and a turbine 43.

The casing 41 is mounted on the outer peripheral portion of a drive plate 44 in which the inner peripheral portion is mounted on the crankshaft 21 with bolts 24 by means of fastening means such as bolts 441 and nuts 442. A ring gear 45 for starting is engaged with the drive gear of a starter motor (not shown) on the outer periphery of the drive plate 44.

The pump 42 is provided to face the casing 41. The pump 42 includes a bowl-shaped pump shell 421 and a plurality of impellers 422 radially arranged in the pump shell 421. The pump shell 421 is fixed to the casing 41 by welding or the like. Installed. Accordingly, the pump shell 421 of the pump 42 is connected to the crankshaft 21 via the casing 41 and the drive plate 44. Therefore, the crankshaft 21 functions as an input shaft of the fluid coupling 40. A pump hub 48 is attached to an inner peripheral end of a pump shell 421 of the pump 42. The pump hub 48 is attached to a cylindrical support portion 600 of the fluid coupling housing 6 which is formed so as to surround the output shaft 46. It is rotatably supported by a bearing 490.

The turbine 43 is disposed in a chamber formed by the pump 42 and the casing 41 so as to face the pump 42. The turbine 43 includes a bowl-shaped turbine shell 431 disposed to face the pump shell 421 of the pump 42, and a plurality of runners 432 radially disposed in the turbine shell 431. . The turbine shell 431 is attached to a turbine hub 47 spline-fitted to an output shaft 46 disposed on the same axis as the crankshaft 21 as the input shaft by welding or other fixing means.

In the illustrated embodiment, the output shaft 4
6 is provided with a working fluid passage 461 formed along the axis. One end of the passage 461 is opened at the left end face in the drawing of the output shaft 46 and communicates with the chamber 40 a formed by the casing 41 and the pump 42, and the other end is opened at the outer peripheral surface of the output shaft 46. It communicates with a radial passage 462.

The fluid coupling device 4 in the illustrated embodiment
Has a fluid storage tank 60 provided in the fluid coupling housing 6 and containing a working fluid. The fluid storage tank 60
It is important to arrange at a position higher than the output shaft 46 on which the turbine 43 of the fluid coupling is mounted, and in the illustrated embodiment, it is arranged at a position higher than the pump 42 and the turbine 43. The fluid storage tank 60 includes a fluid storage space 61 formed by opening the right side in the figure, and is integrally formed with the fluid coupling housing 6 formed of, for example, an aluminum alloy. A lid plate 62 is attached to the right open end of the fluid storage tank 60 in the drawing. The upper wall 63 of the fluid storage tank 60 is provided with a working fluid supply hole 63a and an air breather fitting hole 63b. A cap 64 is attached to the working fluid supply hole 63a, and an air breather 65 is fitted in the breather fitting hole 63b. It is installed. In the illustrated embodiment, a baffle plate 66 is provided below the air breather 65, and the baffle plate 66 is connected to the lid plate 62 and the fluid storage tank 6.
0 and the open end. The fluid coupling housing 6 provided with the fluid storage tank 60 configured as described above includes:
A communication passage 67 is formed to communicate a lower portion of the fluid storage space 61 with a passage 462 provided on the output shaft 46.
Therefore, the fluid storage space 61 of the fluid storage tank 60 is
7, a passage 462, a passage 461, and a working chamber 4a formed by the pump 42 and the turbine 43 through a chamber 40a formed by the casing 41 and the pump 42.

The fluid coupling device 4 in the illustrated embodiment is configured as described above, and a method of filling the working fluid into the fluid coupling 40 will be described below. Fluid storage tank 60
The cap 64 attached to the upper wall 63 is removed, and the working fluid is supplied to the fluid storage space 61 through the working fluid supply hole 63a. The working fluid supplied to the fluid storage space 61 falls naturally through the communication passage 67, the passage 462, and the passage 461, and is formed by the chamber 40a formed by the casing 41 and the pump 42, and by the pump 42 and the turbine 43. Into the working chamber 4a. In this state, since the passage 461 opening to the chamber 40 a formed by the casing 41 and the pump 42 is provided in the axis of the output shaft 46, the working fluid does not flow above the center of the fluid coupling 40. Therefore, if the fluid coupling 40 is rotated at an appropriate rotation speed, the working fluid moves to the outer peripheral side of the inner surface of the fluid coupling 40 due to centrifugal force, so that the working fluid in the fluid storage space 61 of the fluid storage tank 60 is And the inside of the fluid coupling 40 is filled. In this manner, once the working fluid is filled in the fluid coupling 40, the working fluid does not return even if the rotation of the fluid coupling 40 is stopped, and the working fluid is always filled in the fluid coupling 40. State. Then, the cap 64 is fitted into the working fluid supply hole 63a to complete the working fluid filling operation.

Next, the friction clutch 8 will be described. The friction clutch 8 is disposed in a clutch housing 80 mounted on the fluid coupling housing 6 by bolts 81. Friction clutch 8 in the illustrated embodiment
Are a clutch drive plate 82 mounted on the output shaft 46 of the fluid coupling 40, and a transmission shaft 83 disposed on the same axis as the output shaft 46 (in the illustrated embodiment, an input shaft of a transmission (not shown)). ), A driven plate 86 attached to a clutch hub 84 spline-fitted to the transmission shaft 83 and having a clutch facing 85 mounted on the outer periphery thereof, and a pressure plate 87 pressing the driven plate 86 against the clutch drive plate 82.
And a diaphragm spring 8 for urging the pressure plate 87 toward the clutch drive plate 82.
8, a release bearing 89 which is engaged with the inner end of the diaphragm spring 88 and operates with the middle part of the diaphragm spring 88 as a fulcrum 881, and a clutch release fork 90 for operating the release bearing 89 in the axial direction. are doing. In the friction clutch 8 configured as described above, the pressure plate 87 is pressed against the clutch drive plate 82 by the spring force of the diaphragm spring 88 in the state shown in the drawing, and therefore, the clutch facing mounted on the driven plate 86 85 is the clutch drive plate 8
2 and transmitted to the output shaft 46 of the fluid coupling 40 is transmitted to the transmission shaft 83 via the clutch drive plate 82 and the driven plate 86. To interrupt this power transmission, hydraulic pressure is supplied to a slave cylinder (not shown) to operate the clutch release fork 90, and the release bearing 89 is moved to the left in FIG. 1, so that the diaphragm spring 88 is indicated by a two-dot chain line in FIG. By operating as shown, the pressing force on the pressure plate 87 is released, and the power transmission from the clutch drive plate 82 to the driven plate 86 is cut off.

The fluid coupling device 4 in the illustrated embodiment is configured as described above, and its operation will be described below. The driving force generated on the crankshaft 21 (input shaft) of the diesel engine 2 is transmitted to the casing 41 of the fluid coupling 40 via the drive plate 44 as described above. Pump shell 4 of casing 41 and pump 42
Since the pump 21 is integrally formed, the pump 42 is rotated by the driving force. When the pump 42 rotates, the working fluid in the pump 42 is centrifugally moved to the impeller 4.
It flows toward the outer periphery along 22 and flows into the turbine 43 side as shown by the arrow. The working fluid flowing into the turbine 43 flows toward the center and returns to the pump 42 as indicated by an arrow. As described above, the working fluid in the working chamber 4a formed by the pump 42 and the turbine 43 circulates in the pump 42 and the turbine 43, so that the driving torque on the pump 42 side is transmitted through the working fluid to the turbine 43a.
Transmitted to the side. The driving force transmitted to the turbine 43 is transmitted to the output shaft 46 via the turbine shell 431 and the turbine hub 47, and further transmitted to a transmission (not shown) via the friction clutch 8.

As described above, when the fluid coupling 40 operates and the working fluid circulates, the working fluid generates heat due to its friction and thermally expands. The thermally expanded working fluid is absorbed into the fluid storage space 61 through the passage 461, the passage 462, and the communication passage 67. Then, the pressure in the fluid storage space 61 that has risen by absorbing the thermal expansion of the working fluid is released to the atmosphere via the air breather 65. Therefore, it is possible to prevent the pressure inside the fluid coupling 40 from rising due to the thermal expansion of the working fluid.

[0019]

As described above, the fluid coupling device according to the present invention has the following functions and effects.

That is, in the fluid coupling device according to the present invention, a fluid storage tank for storing the working fluid is disposed at a position higher than the output shaft of the fluid coupling, and the fluid storage tank communicates with the working chamber formed by the pump and the turbine. Therefore, even if the fluid coupling operates and the working fluid circulates, and heat is generated due to the circulation, the fluid can be absorbed by the fluid storage tank and the pressure inside the fluid coupling can be prevented from rising. For this reason, it is possible to prevent the occurrence of fatigue fracture and an increase in drag torque of the fluid coupling caused by an increase in the pressure inside the fluid coupling.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an embodiment of a driving device equipped with a fluid coupling device configured according to the present invention.

[Explanation of symbols]

 2: Internal combustion engine 21: Crankshaft 4: Fluid coupling device 40: Fluid coupling 41: Casing 42: Pump 421: Pump shell 422: Impeller 43: Turbine 431: Turbine shell 432: Runner 44: Drive plate 45: Ring gear 46: Output Shaft 47: Turbine hub 48: Pump hub 6: Fluid coupling housing 60: Fluid storage tank 61: Fluid storage space 62: Cover plate 63: Upper wall 64: Cap 65: Air breather 66: Baffle plate 67: Communication passage 8: Friction clutch 80 : Clutch housing 82: Clutch drive plate 83: Transmission shaft 84: Clutch hub 85: Clutch facing 86: Driven plate 87: Pressure plate 88: Diaphragm spring 89: Release bearing 90: Clutch release Zufoku

Claims (2)

[Claims] 1. A fluid coupling comprising: a pump mounted on an input shaft; and a turbine mounted on an output shaft disposed opposite to the pump and arranged on the same axis as the input shaft. In the fluid coupling device, a fluid storage tank containing a working fluid is disposed at a position higher than the output shaft, and the fluid storage tank is communicated with a working chamber formed by the pump and the turbine. apparatus. 2. The fluid coupling device according to claim 1, wherein an air breather is mounted on the fluid storage tank.