JPH03328A - Hydraulic power transmission coupling - Google Patents

Abstract

PURPOSE:To shorten the time for returning from a locked condition by leaking a hydraulic oil in a high-pressure chamber to a low-pressure chamber when a detecting mechanism, provided in a main line for connecting to delivery and suction lines of fluid, is moved at a specified delivery pressure or a specified temperature to close an orifice. CONSTITUTION:When a delivery pressure reaches a specified value, an orifice value 24 is moved to the right against a spring 25 until it comes in contact with the staged portion of a rotor 12. Although a needle valve 26 closes an orifice 23, there exists a clearance 40 between the orifice valve 24 and the needle valve 26 and a hydraulic oil in a high-pressure chamber 16A leaks to a low-pressure chamber 16B through the clearance 40. Accordingly, when a load torque on a coupling is removed, the orifice valve 24 returns to the original position by the spring 25 to shorten the time for returning from a locked condition.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a hydraulic power transmission joint used for distributing driving force in a vehicle.

[Prior Art] The present applicant has proposed a hydraulic power transmission joint in which the joint is locked when a predetermined discharge pressure is reached, as disclosed in Japanese Patent Application No. 63-3115.
This is proposed in issue 31.

This hydraulic power transmission joint is provided between relatively rotatable input and output shafts, and includes a flow rate generating means for causing an amount of fluid to flow according to the rotational speed difference between the two shafts, and a means for generating flow resistance of the fluid. The torque transmission joint, in which the transmission torque between the input and output shafts is controlled by the flow-resistance of the fluid, has an orifice in the main passage that communicates the fluid discharge passage and the suction passage, and the discharge passage side is in a predetermined position. The orifice valve moves against a spring when the discharge pressure reaches the discharge pressure, and the needle valve closes the orifice when the orifice valve moves.

[Problems to be Solved by the Invention] However, in such a hydraulic power transmission joint, when the orifice is completely closed, the hydraulic fluid trapped in the high pressure chamber side will leak to a small amount on the outer diameter of the orifice valve. It just leaks through the gaps. Therefore, when the load torque on the joint is released, there is a problem in that it takes too long to return from the locked state.

The present invention has been made in view of these conventional problems, and by allowing the hydraulic oil in the high pressure chamber to escape to the low pressure chamber when the orifice is closed, it takes less time to recover from the locked state. The object of the present invention is to provide a hydraulic power transmission joint that is free from stress.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a flow rate system that is provided between input and output shafts that are relatively rotatable, and that flows an amount of fluid according to the rotational speed difference between the two shafts. A torque transmission joint comprising a generating means and a means for generating flow resistance of the fluid, and in which the transmission torque between the input and output shafts is controlled by the flow resistance of the fluid, wherein A leak means is provided for leaking hydraulic fluid in the high pressure chamber into the low pressure chamber when the detection mechanism provided in the passage moves at a predetermined discharge pressure or a predetermined temperature to close the orifice of the variable orifice mechanism.

[Function] In the present invention, when the detection mechanism moves to close the orifice of the variable orifice mechanism at a predetermined discharge pressure or a predetermined temperature, the hydraulic oil in the high pressure chamber is released to the low pressure chamber. When the load torque on the joint is released without being trapped in the high pressure chamber, the detection mechanism returns to its original position and it takes no time to return from the locked state.

[Example code] Embodiments of the present invention will be described below based on the drawings.

1 to 3 are diagrams showing a first embodiment of the present invention.

First, to explain the configuration, in FIG. 1, numeral 11 is a cam ring having a cam surface 11A formed on its inner circumference.The cam ring 11 is connected to an input shaft or an output shaft, and rotates integrally with the input shaft or output shaft.

The cam surface 11A has a cam shape in which the flow rate through an orifice (described later) is always constant regardless of changes in rotation angle, and the volume inside the rotor including the plunger chamber and the main passage is always constant.

12 is a rotor rotatably housed in the cam ring 11, and the rotor 12 is connected to an output shaft or an input shaft.
Rotates together with the output shaft or input shaft. Note that 13 is an oil seal interposed between the cam ring 11 and the rotor 12.

As shown in FIG. 2, a plurality of plunger chambers 14 are formed in the rotor 12 in the circumferential direction.
A plurality of plungers 15 are slidably housed inside. Further, a main passage 16 is formed in the center of the rotor 12, and the plunger chambers 14 are communicated through the main passage 16 through a discharge passage 17 and a suction passage 18.

A suction valve (check valve) is installed in the suction passage 18 by a spring 19.
A discharge valve 20 is connected to the discharge passage 17 by a spring 21.
2 are interposed respectively.

An orifice valve 24 as a detection mechanism having an orifice 23 is housed in the main passage 16 so as to be movable at a predetermined discharge pressure via a spring 25. It is defined by a low pressure chamber 16B. A needle valve 26 as a variable orifice mechanism is fixed in the main passage 16, and the needle valve 26 closes the orifice 23 when the orifice valve 24 moves rightward in the figure.

Note that a temperature sensing member may be provided so that the orifice 23 is closed by the needle valve 26 when a predetermined temperature is reached.

Furthermore, a check valve 30 is interposed in the passage 27 communicating with the low pressure chamber 16B via a spring 28, and this check valve 30 causes the inside of the rotor 12 including the plunger chamber 14 and the main passage 16 to be A chamber (inner chamber) and a chamber (outer chamber) formed between the cam ring 11 and the rotor 12 are defined.

31 is a piston, 32 is a holding member, 33 is a holding member 32
This is a spring interposed between the piston 31 and the piston 31.

In addition, 34 to 36 are mounting holes for the input shaft or output shaft, and 37
38 is an oil seal, 38 is a mounting bolt, and 39 is a shutoff valve. Further, the inside of the joint is filled with fluid.

Here, as shown in FIG. 3, when the orifice valve 24 moves by the full stroke amount of the orifice variable stroke amount (A) and comes into contact with the stepped portion of the rotor 12, the orifice valve 24 and the needle valve 26 A gap 40 is provided between them as a leakage means.

Next, the effect will be explained.

When the discharge pressure reaches a predetermined value, the orifice valve 24 moves to the right in the figure against the spring 25, and the rotor 12
It comes into contact with the stepped part. Needle valve 26 is orifice 2
3 is closed, but in this case, there is a gap 40 between the orifice valve 24 and the needle valve 26, and the hydraulic oil in the high pressure chamber 16A leaks from the gap 40 to the low pressure chamber 16B.

Therefore, when the load torque on the joint is released, the orifice valve 24 is returned to its original position by the spring 25, so it does not take much time to return from the locked state.

Next, FIGS. 4 and 5 are diagrams showing a second embodiment of the present invention.

In FIG. 4 and FIG. 5, 41 is a groove 4 serving as a gap.
2 (leakage means), and the circular member 41 is provided at one end side of the orifice valve 24.

Therefore, when the discharge pressure reaches a predetermined value, the orifice valve 2
4 moves, the needle valve 26 closes the circular member 41
Since the orifice 23 is not completely closed,
The hydraulic oil in the high pressure chamber 16A escapes from the groove 42 to the low pressure chamber 16B.

In this embodiment as well, the same effects as in the previous embodiment can be obtained.

FIG. 6 is a diagram showing a third embodiment of the present invention.

In FIG. 6, when the cross-sectional area of the main passage 16 is B1 and the cross-sectional area of the orifice valve 24 is C, (B-C) is designed to be smaller than the cross-sectional area of the orifice 23. Therefore, a bypass passage 431 as a leakage means is formed between the rotor 12 and the orifice valve 24;
When the discharge pressure reaches a predetermined value, the orifice 23 is completely closed, but the hydraulic fluid in the high pressure chamber 16A escapes from the bypass passage 43 to the low pressure chamber 16B. In this embodiment as well, the same effects as in the previous embodiment can be obtained.

FIG. 7 and FIG. 8 are diagrams showing a fourth embodiment of the present invention.

In FIGS. 7 and 8, the orifice valve 24 is flattened, and a bypass passage 44 as a leakage means is formed between the rotor 12 and the flattened surface.

Therefore, when the discharge pressure reaches a predetermined value, the orifice 23 is completely closed by the needle valve 26 due to the movement of the orifice valve 24, but the hydraulic fluid in the high pressure chamber 16A escapes from the bypass passage 44 to the low pressure chamber 16B.

Therefore, in this embodiment as well, the same effects as in the previous embodiment can be obtained.

[Effects of the Invention] As explained above, according to the present invention, when the discharge pressure reaches a predetermined value and the orifice valve moves to close the orifice, the hydraulic fluid in the high pressure chamber is released to the low pressure chamber. Therefore, when the load torque on the joint is released, the orifice valve returns to its original position, so it takes less time to return from the locked state.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing the first embodiment of the present invention, FIG. 2 is a view taken along the line A-A in FIG. FIG. 6 is a diagram showing a third embodiment, and FIGS. 7 and 8 are diagrams showing a fourth embodiment. In the figure, 11... cam ring, 11A... cam surface, 12... rotor, 13... oil seal, 14... plunger chamber, 15... plunger 16... main passage, 16A...High pressure chamber, 16B...Low pressure chamber, 17...Discharge path, 18...Suction path, 19...Spring, 20...Suction valve, 21...Spring, 22...・Discharge valve, 23... Orifice, 24... Orifice valve, 25... Spring, 26... Needle valve, 27... Passage, 28... Spring, 30... Check valve, 31...Piston, 32...Holding member, 33...Spring, 34-36...Mounting hole, 37...Oil seal, 38...Mounting bolt, 39...Shutoff valve, 40 ... Clearance (leakage means), 41 ... Circular member (leakage means), 42 ... Groove, 43.44 ... Bypass passage (leakage means). Patent applicant: Fuji Iron Works Co., Ltd.

Claims (3)

[Claims] (1) Provided between relatively rotatable input and output shafts, comprising a flow rate generating means for causing an amount of fluid to flow according to the rotational speed difference between the two shafts, and a means for generating flow resistance of the fluid, the fluid In a torque transmission joint where the transmission torque between the input and output shafts is controlled by the flow resistance of 1. A hydraulic power transmission joint comprising a leak means for leaking hydraulic oil in a high pressure chamber into a low pressure chamber when the orifice of the variable orifice mechanism is closed. (2) The hydraulic power transmission joint according to claim 1, wherein the leakage means is a gap provided between the detection mechanism and the variable orifice mechanism. (3) The hydraulic power transmission joint according to claim 1, wherein the leakage means is a bypass passage provided in the detection mechanism.