JPH0615142Y2 - Liquid coupling device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a liquid coupling device, for example, a variable capacity liquid coupling device used as a temperature-sensitive fan coupling device for a cooling device of an internal combustion engine. Pertain.

2. Description of the Related Art A variable displacement liquid coupling device used as a temperature-sensitive fan coupling device or the like for a cooling device of an internal combustion engine generally includes a shaft member and a shaft member that is concentrically rotatable with respect to the shaft member. A carried coupling housing, a partition for partitioning a chamber space in the coupling housing into a liquid joint working chamber and a liquid storage chamber, and the liquid joint fixed in the liquid joint working chamber and concentric with the shaft member. A labyrinth passage is formed in the working chamber together with the coupling housing to allow the working liquid to pass therethrough, and a relative rotation with respect to the coupling housing causes a pumping action to discharge the working fluid in the working chamber of the liquid joint toward the liquid storage chamber. A rotor; a working liquid supply passage for guiding working liquid from the liquid storage chamber to the liquid working chamber; And a first control valve for selectively opening and closing the supply passage. This type of liquid coupling device is disclosed in U.S. Pat. No. 3,587,801 and Japanese Utility Model Laid-Open No. 56-95622.
It is described in each publication of Japanese Utility Model Publication No. 59-39218.

Problems to be Solved by the Invention In the liquid coupling device having the above-described structure, when the working liquid supply passage is open, the working liquid flows from the liquid storage chamber to the working chamber of the liquid joint through the working liquid passage, Since this exists in the labyrinth passage between the coupling housing and the rotor, the viscosity of the working liquid causes torque transmission in a liquid coupling manner between the shaft member and the coupling housing. When the working liquid supply passage is closed by the control valve, the working liquid in the liquid joint working chamber is discharged to the liquid storage chamber by the pumping action of the rotor while the supply of the working liquid from the liquid storage chamber is cut off. The working liquid is not present in the labyrinth passage between the coupling housing and the rotor, and torque transmission between the shaft member and the coupling housing is substantially eliminated.

When the viscosity of the working fluid such as silicone oil filled in the coupling housing is increased to reduce the power loss due to the slip, the working fluid supply passage is opened and the shaft member when the liquid coupling action is performed is performed. The rotational speed difference with the coupling housing is reduced. This is significant for increasing the torque transmission efficiency, but when the hydraulic fluid supply passage is closed by the control valve to disconnect the coupling from the above-mentioned state, the inside of the liquid coupling operating chamber is closed. It takes a long time for the working liquid to be discharged to the liquid storage chamber, and its cutting responsiveness becomes very poor. Therefore, when the cooling device for the internal combustion engine is driven through such a fan coupling device, the cooling fan rotates at a high speed during the delay in the disconnection response, which may cause the internal combustion engine to be overcooled. Thus, it takes a long time for the working liquid in the fluid coupling working chamber to be discharged to the liquid storage chamber because this discharging is performed by the pumping action of the relative rotation of the rotor with respect to the coupling housing. That is, the smaller the relative rotational speed between the shaft member and the coupling housing, the later the discharge of the working liquid remaining in the liquid coupling working chamber toward the liquid storage chamber due to the above-mentioned pump action, and the liquid coupling device It takes time to switch from the connected state to the disconnected state.

An object of the present invention is to provide an improved liquid coupling device which solves the above problems.

According to the present invention, a shaft member, a coupling housing rotatably supported by the shaft member concentrically with respect to the shaft member, and the coupling housing are provided. A partition for partitioning the inner chamber space into a liquid joint working chamber and a liquid storage chamber, and a working liquid in the liquid joint working chamber that is fixed concentrically to the shaft member in the liquid joint working chamber together with the coupling housing. A labyrinth passage that passes through the rotor and a pump rotor that discharges the working fluid in the liquid joint working chamber toward the liquid storage chamber by relative rotation with respect to the coupling housing; and the liquid joint working from the liquid storage chamber. A liquid cup having a working liquid supply passage for guiding the working liquid to the chamber and a first control valve for selectively opening and closing the working liquid supply passage. In the ring device, the coupling housing is movably supported between a first position for closing the working liquid supply passage and a second position for opening the working liquid supply passage, and is elastically biased by a resilient biasing means. The rotor is elastically urged from the second position toward the first position, and the rotor rotates in response to an increase in relative rotational speed between the two due to a delay in following the rotation of the coupling housing with respect to the rotation of the rotor. A second control valve which is biased to a greater extent from the first position toward the second position via the viscosity of the working liquid against the biasing force of the elastic biasing means; Corresponding to the control valve being biased to the position for closing the working liquid supply passage, the interlocking means biases the second control valve to the second position against the biasing force of the elastic biasing means. Have and It is achieved by a liquid coupling device according to claim and.

Advantageous Effects and Advantages of the Invention According to the above-mentioned configuration, when the relative rotation speed between the shaft member and the coupling housing becomes a predetermined value or less, the opening degree of the working liquid supply passage is reduced by the second control valve, Since the flow rate of the working liquid supplied from the storage chamber to the liquid joint working chamber is reduced, the transmission torque capacity by the liquid joint is reduced accordingly, and the relative rotational speed between the shaft member and the coupling housing is increased. Due to the balance of such control, the relative rotational speed between the shaft member and the coupling housing does not become smaller than a predetermined value, and at least a predetermined relative rotational speed is maintained between the shaft member and the coupling housing, whereby the required rotor rotation speed is maintained. When the pumping action is secured and the working liquid supply passage is closed by closing the first control valve, the working liquid in the liquid joint working chamber is quickly transferred to the liquid storage chamber. The liquid is discharged quickly, and the liquid coupling device is switched from the connected state to the disconnected state with good responsiveness.

Embodiment Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 and 2 show an embodiment in which the liquid coupling device according to the present invention is constructed as a temperature-sensitive coupling device. In these figures, 10 is a shaft member, which is directly driven to rotate by an internal combustion engine (not shown). The shaft member 10 includes a front cover 14 and a rear cover 16 assembled by bolts 12.
The rear cover of the coupling housing 18 is concentrically and rotatably carried by a ball bearing 20 with a seal. The coupling housing 18 has bolts 12
A cooling fan (not shown) can be attached.

A partition plate 22 is provided inside the coupling housing 18 to divide the internal space of the coupling housing into two. The partition plate 22 has a liquid joint working chamber 24 on the rear cover 16 side and a liquid storage chamber 2 on the front cover 14 side.
6 are each bounded.

A disk-shaped rotor 28 is arranged in the liquid joint working chamber 24. The rotor 28 is fixedly connected to the shaft member 10 in the liquid joint working chamber 24, is supported by the shaft member 10, and can rotate relative to the coupling housing 18.

The rear cover 16 of the coupling housing 18 and the rotor 28 are provided with a plurality of concentric annular projections 30 and 32 on their opposing surface portions.
And 32 are different from each other, and the coupling housing 1
A labyrinth passage 34 extending in the radial direction is defined between the rotor 8 and the rotor 28.

The rotor 28 has a gear pump tooth portion 36 on its outer peripheral portion, performs a pumping action by relative rotation with the coupling housing 18, and forms the working liquid in the liquid joint working chamber 24 on the front cover 14. The liquid is returned to the working liquid return passage 38 under pressure and discharged to the liquid storage chamber 26.

The rotor 28 is provided with a plurality of through holes 40 for guiding a working liquid such as silicon oil from the liquid storage chamber 26 side of the liquid joint working chamber 24 to the labyrinth passage 34 side, spaced apart from each other in the circumferential direction. ing.

The partition plate 22 has a liquid joint working chamber 24 from the liquid storage chamber 20.
A working liquid supply hole 42 is provided which operates as a working liquid supply passage for supplying the working liquid to.

In the liquid storage chamber 26 of the coupling housing 18, a temperature sensitive valve 44 as a first control valve for opening and closing the working liquid supply hole 42 is provided. The temperature sensitive valve 44 is the partition plate 22.
It is configured as a plate-like valve element that is in sliding contact with one surface of the first cover, and is rotatably supported by the front cover 14 by a support shaft 46. The support shaft 46 is locked and connected to a core end portion of a spiral bimetal 48 arranged at the front portion of the front cover 14. The outer end of the spiral bimetal 48 is locked to the front cover 14 by the hook member 50, whereby the spiral bimetal 48 rotates counterclockwise with respect to the support shaft 46 as seen in FIG. It is designed to give torque. As a result, when the temperature sensed by the spiral bimetal 48 is equal to or lower than a predetermined value, the temperature sensitive valve 44 is located at the valve closing position for closing the working liquid supply hole 42, as shown in FIG. As shown in FIG. 2, the working liquid supply hole 42 is opened by rotational displacement in a counterclockwise direction as the sensed temperature rises.

A rotary valve 52 as a second control valve for controlling the opening degree of the working liquid supply hole 42 is provided between the rotor 28 of the fluid coupling working chamber 24 and the partition plate 22. The rotary valve 52 is in sliding contact with the other surface of the partition plate 22 and is rotatably supported by the support shaft 54 concentrically with the coupling housing 18 from the partition plate 22. In the state shown in FIG. 2, the rotary valve 52 is forced to the end position in the clockwise direction in the figure by the temperature sensitive valve 44 which has returned to the position where the working liquid supply hole 42 is closed as described below. However, when the temperature sensitive valve 44 is rotated counterclockwise in the drawing as the sensed temperature rises and the forced bias in the clockwise direction with respect to the rotary valve 52 is released, the temperature sensitive valve 44 is rotated. The valve 52 is the rotor 2
2 due to the relative rotation between the shaft 8 and the coupling housing 18 (the shaft member 10 is driven clockwise in FIG. 2), which is given by the viscosity of the working liquid in the fluid coupling working chamber 24. Seen in the figure, the torque is applied in the clockwise direction and the torsion coil spring 56 takes a rotational position according to the equilibrium relationship between the torque in the counterclockwise direction as seen in FIG. Along with the reduction of the torque, the spring force of the torsion coil spring 56 rotates counterclockwise as viewed in FIG. 2 to reduce the opening degree of the working liquid supply hole 42.

The partition plate 22 is provided with an arcuate slit 58 concentric with the rotation center of the temperature sensitive valve 44.
A force-valve opening claw 60 provided integrally with the temperature-sensitive valve 44 is engaged with this. The forced valve opening claw 60 penetrates through the arcuate slit 58 and engages with the rotary valve 52. When the temperature sensitive valve 44 is in the closed position as shown in FIG. 2, the rotary valve 52 is twisted by a coil spring. It is designed to be driven in the clockwise direction as viewed in FIG. 2 against the spring force of 56 and forcibly biased to the fully open position where it abuts against the stopper 62.

In the liquid coupling device having the above-described structure, when the temperature sensed by the spiral bimetal 48 is low, the temperature sensitive valve 44 is located at the valve closed position as shown in FIG. The holes 42 are closed to prevent the working liquid in the liquid storage chamber 26 from being supplied to the fluid coupling working chamber 24. At this time, since there is no working liquid in the labyrinth passage 34, the liquid coupling device does not perform a substantial fluid coupling action and is in a disconnected state. Even if the rotor 28 rotates together with the fan drive shaft 10 by the internal combustion engine, the coupling does not occur. The housing 18 does not substantially rotate.

When the temperature sensed by the spiral bi-melter 48 rises, the spiral bi-metal 48 is thermally deformed accordingly, causing the temperature sensing valve 44 to rotate counterclockwise as viewed in FIG. The supply hole 42 comes to be opened. As a result, the working liquid in the liquid storage chamber 26 flows to the fluid coupling working chamber 24 through the working liquid supply hole 42, and further to the labyrinth passage 34 through the through hole 40, and the working liquid exists in the labyrinth passage. As a result, torque is transmitted between the rotor 28 and the coupling housing 18 due to the viscosity of the working liquid, and the rotor 2 in the clockwise direction as seen in FIG.
With the rotation of 8, the coupling housing 18 also rotates in the same direction.

As described above, the rotary valve 52 is forcibly biased in the clockwise direction as viewed in FIG. 2 by the temperature sensitive valve 44 via the forced valve opening claw 60, until the temperature sensitive valve 44 is fully opened. The supply hole 42 is held at a valve opening position that does not reduce the opening degree.

The working liquid supplied to the labyrinth passage 34 is directed toward the outer side of the rotor 28 by the centrifugal force, and is returned to the inside of the liquid storage chamber 26 from the working liquid returning passage 38 by the pumping action of the teeth portion 36. Thus, when the working liquid supply hole 42 is opened, the working liquid is stored in the liquid storage chamber 2
From 6 through the working liquid supply hole 42 enters the fluid coupling working chamber 24, returns to the liquid storage chamber 26 by the pump action of the rotor 28, repeatedly circulates these, and at that time, performs the liquid coupling action in the labyrinth passage 34, The rotor 28 and the coupling housing 18 are connected in a torque transmitting relationship.

After the temperature-sensing valve 44 is sufficiently opened, the rotary valve 52 is released from the forced-valve opening by the forced-valve opening claw 60, and due to the relative rotation between the rotor 28 and the coupling housing 18, the liquid joint working chamber 24 is released. The balance between the torque in the clockwise direction as seen in FIG. 2 and the torque in the counterclockwise direction as seen in FIG. 2 due to the torsion coil spring 56 due to the viscosity of the working liquid existing between the rotor 28 and the rotary valve 52 of FIG. The sled rotation position is determined by the relationship. When the difference in the number of rotations between the rotor 28 and the coupling housing 18 decreases, the rotor 2 passes through the working liquid.
The torque transmitted to the rotary valve 52 from 8 is reduced, whereby the rotary valve 52 is rotationally displaced counterclockwise as viewed in FIG. 2 by the spring force of the torsion coil spring 56, and the temperature sensitive valve 44
Apart from this, the opening degree of the working liquid supply hole 42 can be reduced. When the opening degree of the working liquid supply hole 42 decreases,
Along with this, the flow rate of the working liquid supplied from the liquid storage chamber 26 to the liquid joint working chamber 24 is reduced, so that the transmission torque capacity of the liquid coupling device is reduced, and accordingly, the rotor 28 and the coupling housing are reduced. The rotational speed difference from 18 increases. When the rotational speed difference increases, the torque in the clockwise direction as seen in FIG. 2 that is transmitted from the rotor 28 to the rotary valve 52 via the viscosity of the working liquid increases again.
The opening degree of the working liquid supply hole 42 increases again, and accordingly, the flow rate of the working liquid supplied from the liquid storage chamber 26 to the liquid joint working chamber 24 increases again, and the transfer torque capacity of the liquid coupling device increases again. Increase. This balance control prevents the rotational speed difference between the rotor 28 and the coupling housing 18 from falling below a predetermined value, and maintains the relative rotational speed between the two at a predetermined value or above.

When the temperature sensed by the spiral bimetal 48 falls below the connected state of the liquid coupling device and the temperature sensitive valve 44 closes, and the working liquid supply hole 42 closes, then between the rotor 28 and the coupling housing 18 at that time. Is always maintained at a relative rotational speed equal to or higher than a predetermined value, a pumping action of the rotor 28 having a predetermined performance or higher is obtained, whereby the working liquid in the fluid coupling working chamber 24 is returned to the working liquid return passage 38.
After that, the liquid coupling device is quickly discharged to the liquid storage chamber 26, and the liquid coupling device is disconnected with good responsiveness.

FIG. 3 shows the relationship between the cooling water temperature, the operation of the temperature sensitive valve, and the rotation speed of the coupling housing, that is, the rotation speed of the cooling fan. In the liquid coupling device according to the present invention,
When the temperature sensitive valve 44 is closed by the operation of the spiral bimetal 48 at the time point T ₁ , the liquid coupling device is immediately disconnected at the time point T ₂ after a short time ΔT has elapsed, whereby the cooling fan is closed. Although the number of revolutions decreases rapidly, in the conventional case, the time T that is considerably longer than the time T ₁ has elapsed because the working liquid in the fluid coupling working chamber 24 is not rapidly discharged at this time. _{At 3, the} liquid coupling device becomes disconnected for the first time, and the cooling fan speed decreases.

FIG. 4 and FIG. 5 show another embodiment of the forced biasing mechanism of the rotary valve 52 by the temperature sensitive valve 44 in the liquid coupling device according to the present invention. In this embodiment, the forced valve opening claw 60 is attached to the temperature sensitive valve 44 by the leaf spring 64, and can be moved in the thickness direction thereof, that is, in the left and right direction in the figure, and the temperature sensitive valve 44 is shown in the figure. Is biased to the left. The forced valve opening claw 60 extends through the arcuate slit 58 of the partition plate 22 to a position where it engages with the rotary valve 52, and at the same time, the slit 68 provided in the temperature sensitive valve 44.
At the left end 60a thereof to abut the circumferential cam surface 66 provided on the inner wall of the front cover 14, and
It is pressed to the corresponding contact position by the spring force of No. 4. The cam surface 66 has two cam surfaces 66a and 66b that are staggered from each other at a position midway along the circumferential direction. When the temperature sensitive valve 44 is in the valve closing position, the forced valve pawl 60 has the cam surface 6 as shown by the solid line in FIG.
When the temperature sensitive valve 44 is in the open position, the cam surface 66b, as shown by the phantom line II in FIG.
And the amount of protrusion to the liquid joint working chamber 24 is reduced. The forced valve opening claw 60 contacts the rotary valve 52 at the end opposite to the contact end with the cam surface 66, and this end contacts the inclined surface 60b and the vertical end surface 60.
and c.

When the temperature sensitive valve 44 is in the closed position for closing the working liquid supply hole 42, the forced valve opening claw 60 is in the position shown by the solid line in FIG. 5, and at this time, the rotary valve 52 is forcibly opened. 60
And is held in the valve open position by abutting on the vertical end surface 60c. When the temperature sensitive valve 44 starts to open, the forced valve opening claw 60 also moves along with this valve opening movement, and the forced valve opening claw 60 comes apart from the cam surface 66a and corresponds to the cam surface 66b.
Until the rotary valve 52 is given a torque via the viscosity of the working liquid in the liquid joint working chamber 24, the rotary valve is pressed against the vertical end surface 60c of the forced valve opening claw 60 by the spring force of the torsion coil spring 56. As a result, the forced valve opening claw 60 maintains the protruding state as shown by the phantom line I in FIG.

After that, the working liquid flows from the liquid storage chamber 26 to the liquid joint working chamber 24 through the working liquid supply hole 42, and when torque is applied to the rotary valve 52 by the viscosity of the working liquid, the rotary valve 52 opens the forced valve opening claw 60. When the pressing is stopped, the forced valve opening claw 60 moves toward the front cover 14 by the spring force of the leaf spring 64 and comes into contact with the cam surface 66b. From this point onward, even if the rotary valve 52 comes into contact with the forced valve opening claw 60, it contacts the inclined surface 60b of the forced valve opening claw 60 as shown by the phantom line II in FIG.

In the process of closing the temperature sensitive valve 44 from the above-described state, the rotary valve 52 is tilted at the inclination angle 60b of the forced valve opening claw 60 until the forced valve opening claw 60 rides on the cam surface 66a from the cam surface 66b. Since the valve can be rotated in the valve closing direction until it is engaged with, the rotary valve 52 is compared with the case where the rotary valve 52 is engaged with the vertical surface 60c of the forced opening pawl 60 during the process of opening the temperature sensitive valve 44. Therefore, the distance between the temperature sensitive valve 44 and the rotary valve 52 can be made smaller, and when the temperature sensitive valve 44 starts to close the working liquid supply hole 42, the temperature sensitive valve 44 causes the rotary valve 52 to move. It is too early to be forcibly driven in the circumferential direction, and the working liquid supply hole 42, which has been throttled by the rotary valve 52 until then, is greatly opened, and the rotational speed between the rotor 28 and the coupling housing 18 by the rotary valve 52 is increased. The situation that the effect of maintaining the difference is lost is prevented. . In the process of opening the temperature sensitive valve 44, the rotary valve 52 is connected to the vertical surface 6 of the forced valve opening claw 60 as described above.
Since the temperature sensitive valve 44 and the rotary valve 52 are engaged with the hydraulic fluid supply hole 4a,
Both are largely separated from each other so as not to close 2.

By the time the temperature sensitive valve 44 reaches the valve closing position where the hydraulic fluid supply hole 42 is completely closed, the forced valve opening claw 60 is riding on the cam surface 66a, and the rotary valve 52 contacts the forced valve opening claw 60. The contact position moves from the inclined surface 60b to the vertical end surface 60c.

In the above, the present invention has been described in detail with reference to specific embodiments, but the present invention is not limited to these.
It will be apparent to those skilled in the art that various embodiments are possible within the scope of the invention.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment in which the liquid coupling device according to the present invention is constructed as a temperature-sensitive fan coupling device, and FIG. 2 is a temperature-sensitive fan coupling device shown in FIG. FIG. 3 is a rear view of the valve device portion of FIG. 3, FIG. 3 is a graph showing the operating characteristics of the liquid coupling device according to the present invention shown in FIGS. 1 and 2, and FIG. 4 is a liquid coupling device according to the present invention. FIG. 5 is a vertical sectional view showing the main part of another embodiment of the rotary valve forced biasing mechanism using the temperature sensitive valve, and FIG. 5 is a bottom view of the structure shown in FIG. 10 ... Fan drive shaft, 12 ... Bolt, 14 ... Front cover, 16 ... Rear cover, 18 ... Coupling housing, 20 ... Sealed ball bearing, 22 ...
... Partition plate, 24 ... Liquid joint working chamber, 26 ... Liquid storage chamber, 28 ... Rotor, 30, 32 ... Ribs, 34 ... Labyrinth passage, 36 ... Tooth portion, 38 ... Working liquid return Passage, 40 ... Through hole, 42 ... Working liquid supply hole, 44 ...
… Temperature sensitive valve, 46 …… Support shaft, 48 …… Spiral bimetal, 50 …… Hook member, 52 …… Rotating valve, 54 ……
Support shaft, 56 ... Torsion coil spring, 58 ... Arc slit, 60 ... Forced valve opening claw, 62 ... Stopper, 64 ...
… Leaf spring, 66… Cam surface, 68… Slit

Claims (1)

[Scope of utility model registration request] 1. A shaft member, a coupling housing rotatably supported by the shaft member concentrically with respect to the shaft member, and a chamber space in the coupling housing as a liquid joint working chamber and a liquid storage chamber. A partition and a partition which is fixed concentrically to the shaft member in the liquid joint working chamber and which forms a labyrinth passage for passing working liquid together with the coupling housing in the liquid joint working chamber and relative rotation with respect to the coupling housing. A rotor that performs a pumping action to discharge the working fluid in the liquid joint working chamber toward the liquid storage chamber, a working liquid supply passage that guides the working liquid from the liquid storage chamber to the liquid joint working chamber, and the working liquid In a liquid coupling device having a first control valve that selectively opens and closes a supply passage, the liquid coupling device comprises: Is movably supported between a first position for closing the working liquid supply passage and a second position for opening the working liquid supply passage, and is elastically biased from the second position to the first position. Is elastically urged toward the position, and the rotor rotates through the viscosity of the working liquid in response to an increase in relative rotational speed between the two due to a delay in following the rotation of the coupling housing with respect to the rotation of the rotor. A second control valve that is biased to a greater extent from one position toward the second position against the urging force of the elastic urging means, and the first control valve connects the working liquid supply passage. A liquid cup, which corresponds to biasing to the closed position, and interlocking means for biasing the second control valve to the second position against the biasing force of the elastic biasing means. Ring device.