JP2003156124A - Fluid coupling - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluid coupling which eliminates slip (sliding) loss and improves mechanical efficiency of power transmission by providing a clutch mechanism between a driving shaft side and a driven shaft side and by providing the same driven shaft rotational speed as a driving shaft rotational speed from a prime mover. SOLUTION: In the fluid coupling, fluid is used as a medium for power transmission, and power is transmitted by rotating vanes 5 acting as a water turbine provided on a driven shaft 9 by kinetic energy applied to the fluid by vanes 4 acting as a pump provided on a driving shaft 1 driven by the prime mover. A clutch is provided between the driving shaft 1 side and the driven shaft 9 side. Power is transmitted by engaging the clutch in a state of feeding oil to portions of the vanes 4 and the vanes 5 and transmitting rotational power and providing the same rotational speed between the driving shaft 1 and the driven shaft 9. After operating the clutch, an oil level of hydraulic oil is prevented from reaching the vanes acting as a pump or the vanes acting as a water turbine by drawing out or discharging the hydraulic oil remaining in a fluid coupling hydraulic oil chamber.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid coupling for transmitting power from a drive shaft side to a driven shaft side by using kinetic energy of a fluid, and particularly to a clutch mechanism provided with the clutch mechanism. The present invention relates to a fluid coupling in which a drive shaft and a driven shaft are mechanically coupled to each other to make the rotation speeds of both shafts equal to each other, thereby eliminating a slip loss and improving power transmission efficiency from a prime mover to a driven machine. 2. Description of the Related Art Conventionally, a pumping blade is connected to a drive shaft and a water wheel is connected to a driven shaft, and power is transmitted from the driving shaft to the driven shaft via a fluid filled in a casing. 2. Description of the Related Art Fluid couplings are known, and there are a constant speed rotation type fluid coupling and a variable speed type fluid coupling. Conventionally, in variable-speed fluid couplings, a scoop tube is used to increase or decrease the amount of hydraulic oil in the coupling so that the rotational speed on the load side can be steplessly changed from the maximum rotational speed to the minimum rotational speed. ing. At this time, since the power transmission medium is a liquid, the power transmission loss appears as a decrease in the rotational speed. Therefore, even if the fluid coupling is filled with 100%, the maximum rotational speed of the driven shaft is equal to the drive shaft. Does not match that of the above, resulting in a value reduced by 2 to 3%. In a descaling pump used in a hot rolling facility, rapid acceleration rotation speed control is indispensable for operational reasons of the rolling facility, and a rapid-change fluid coupling is used for that purpose. The rapid-change fluid coupling rapidly fills / discharges the oil amount in the impeller and changes the transmission torque from the maximum (when refueling: maximum rotation speed) to the minimum (when discharging oil: minimum rotation speed). A fluid coupling that performs variable speed operation.
Filling / discharging is performed by opening or closing a hydraulic oil switching valve to fill or substantially empty the oil amount in the impeller. [0004] In recent years, the problem of energy saving has been highlighted, and power loss due to slippage of a drive shaft and a driven shaft in this fluid coupling has been taken up as a target item of energy saving. Energy saving by eliminating slips is an issue. SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and provides a clutch mechanism between a drive shaft side and a driven shaft side to make the rotation speed of the drive shaft from the prime mover equal to the rotation speed of the driven shaft. , Eliminate its slip (slip) loss,
It is an object of the present invention to provide a fluid coupling capable of improving power transmission efficiency. SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention uses a fluid as a medium for power transmission, and a kinetic energy applied to the fluid by a pumping blade provided on a drive shaft driven by a prime mover. In the fluid coupling for transmitting power by rotating the water turbine working blade provided on the driven shaft, a clutch is provided between the drive shaft side and the driven shaft side, and the pump working blade and the water turbine working blade are filled with oil. In the state where the rotational power is being transmitted, it is possible to perform power transmission with the drive shaft and the driven shaft at the same rotational speed by coupling the clutch, and after operating the clutch, the clutch remains in the fluid coupling hydraulic oil chamber. The hydraulic oil is drained out or the hydraulic oil remaining in the fluid coupling hydraulic oil chamber is discharged so that the oil level of the hydraulic oil does not reach the pump operating blade and the water turbine operating blade. Ah You. According to the present invention, a clutch is provided between the drive shaft side and the driven shaft side of the fluid coupling, and after the rotational speed of the driven shaft reaches the maximum speed, the clutch is connected to connect the drive shaft and the driven shaft. Can be mechanically coupled to eliminate slippage between the drive shaft and the driven shaft. For the clutch, for example, a multi-plate clutch having a simple structure and easy control is used, and hydraulic oil is supplied to the clutch by a hydraulic pump to attach and detach the clutch by hydraulic pressure. And, in the present invention, during operation of the fluid coupling, after the clutch is connected and the drive shaft and the driven shaft are directly connected, the hydraulic oil remaining in the fluid coupling hydraulic oil chamber is removed, or the fluid coupling operation is performed. By discharging the hydraulic oil remaining in the oil chamber so that the oil level of the hydraulic oil does not fall on the pump operating blade and the water turbine operating blade, the mixing and stirring power by the fluid in the fluid coupling during full speed operation is reduced, Further, the energy saving effect can be improved. An embodiment of the fluid coupling according to the present invention will be described below with reference to the drawings. FIG. 1 is a system diagram showing an overall system of a first embodiment of the fluid coupling of the present invention, and FIG. 2 is a sectional view showing a detailed structure of a power transmission unit of the fluid coupling shown in FIG. The fluid coupling of the present invention includes a multi-plate clutch between the drive shaft side and the driven shaft side. When a multi-plate clutch is used for a fluid coupling, hydraulic oil is supplied to a hydraulic cylinder attached to the clutch by a separately provided hydraulic pump, and multiple hydraulic fluid is supplied by a built-in piston using centrifugal oil pressure generated in the cylinder chamber. Press the plate clutch to connect the clutch. A hydraulic pump that pumps hydraulic oil from the outside
There is a method of driving by using a separately provided electric motor, and a method of driving by a belt or a gear transmission method from the driving machine. As shown in FIG. 1, a drive shaft 1 is rotatably supported by a radial bearing 2 and a thrust bearing 3. A pumping blade (impeller) 4, a fluid coupling housing 20, and a clutch chamber 13 are fixed to a distal end portion of the drive shaft 1. The clutch chamber 13 is provided with a plurality of drive-side friction plates 7, a clutch piston 11, and the like. The clutch chamber 13 and the clutch piston 11
Defines a cylinder chamber 10. A driven shaft 9 is disposed adjacent to the drive shaft 1, and the driven shaft 9 is rotatably supported by a radial bearing 2 and a thrust bearing 3. A water turbine working blade (runner) 5 is fixed to the tip end of the driven shaft 9, and the water turbine working blade 5 is arranged to face the pump working blade 4. The driven shaft 9 is provided with a plurality of driven-side friction plates 12, and these driven-side friction plates 12 are arranged alternately with the drive-side friction plates 7 in the clutch chamber 13 (see FIG. 2).
The drive-side friction plates 7 and the driven-side friction plates 12 as the clutch plates arranged alternately constitute a multi-plate clutch. Reference numeral 22 denotes a fixing plate fixed in the clutch chamber 13 (see FIG. 2). As shown in FIG. 1, hydraulic oil is stored in the lower part of the fluid coupling case 30. The hydraulic oil is pressurized by the hydraulic pump 16, and the hydraulic oil is supplied to the fluid coupling hydraulic oil minimum oil amount setting orifice 32. Almost no pressure to about 0.2MP on the pumping blade 4 of the fluid coupling by the fluid coupling oil supply pipe 17 via
Supply with a. Since the amount of oil supplied at this time is smaller than the amount of oil discharged from the hydraulic oil discharge nozzle 6, the fluid coupling is operated at the minimum rotation speed. At this time, when the hydraulic oil switching valve 15 for the fluid coupling is opened, the hydraulic oil passes through the hydraulic oil supply pipe 17 via the hydraulic oil switching valve 15 for the fluid coupling to the pump working blade 4 of the fluid coupling with almost no pressure to about 0.1. It is supplied at 2 MPa. Reference numeral 19 denotes a relief valve that returns hydraulic oil into the fluid coupling case 30 when the pressure in the pipe becomes higher than necessary. The supplied hydraulic oil is supplied to the pumping blade 4
Is given kinetic energy by the turbine blades 5
To give energy to the water turbine working blade 5 to drive the driven shaft 9
To transmit power. The hydraulic oil supplied into the fluid coupling housing 20 including the pumping blade 4 and the water wheel 5 is
Fluid coupling case 30 discharged from hydraulic oil discharge nozzle 6
Return to the bottom. Since the oil supply amount from the fluid coupling oil supply pipe 17 is much larger than the discharge amount from the hydraulic oil discharge nozzle 6, the fluid coupling housing 20 is rapidly filled with the hydraulic oil, and the rotation speed of the driven shaft 9 also increases rapidly. The maximum rotation speed. At this maximum rotational speed, a slip (slip) of usually 2 to 3% occurs between the drive shaft 1 and the driven shaft 9, and the driven shaft 9 rotates with a slight delay. In this state, when the clutch switching valve 14 is opened and hydraulic oil is supplied to the clutch oil supply pipe 18 by the hydraulic pump 16, the hydraulic oil that has entered the cylinder chamber 10 through the clutch oil supply pipe 18 Due to friction between the inner surface of the clutch chamber 11 and the clutch piston 11, the clutch chamber 13 starts rotating at substantially the same rotation speed. Therefore, the cylinder chamber 10
A pressure is generated therein by a centrifugal force caused by the rotation of the hydraulic oil, and the clutch piston 11 is pushed out by this pressure to press the driving-side friction plate 7 of the multi-plate clutch toward the driven-side friction plate 12. Since the plurality of drive-side friction plates 7 and the driven-side friction plates 12 are alternately overlapped, the driven-side friction plates 12 also rotate at the same rotational speed as the drive-side friction plates 7, and the drive shaft 1 and the driven shaft 9 slide. Drive shaft 1 rotating at the same rotational speed without
To the driven shaft 9. A clutch hydraulic oil discharge nozzle 8 is provided on the outer peripheral portion of the clutch chamber 13, and the hydraulic oil in the clutch chamber 13 is constantly discharged little by little by the rotation of the drive shaft 1. Therefore, when the clutch switching valve 14 is closed, the operating oil in the cylinder chamber 10 runs out, and as a result,
Since there is no pressing force for the clutch piston 11 to press the drive-side friction plate 7, the clutch is released by the spring attached to the clutch, and power transmission is stopped. The hydraulic oil discharge nozzle 6 and the clutch hydraulic oil discharge nozzle 8 are connected to an oil return pipe 25. Before the transmission of power with the clutch in the engaged state, a slip of 2-3% occurs between the rotation speeds of the pump operation blade 4 and the water turbine operation blade 5. This is caused by fluid friction between both blades or collision loss of fluid, which appears as a difference in rotation speed, and is inevitable in transmitting power through fluid It is a principle. However, as described above, from the viewpoint of energy saving, as shown in FIG. 1, a multiple disc clutch is provided as a means for eliminating the power loss. When the clutch is connected, the power is transmitted by friction between the clutch plates, but the slip between the clutch plates can be stopped by increasing the contact pressure of the clutch plates, so that the power is transmitted without loss. At this time, the fluid coupling housing 2 is still in operation.
Since the working oil is filled in 0, the power transmission between the fluid coupling blades is also performed, so that the power transmission by the clutch is small and the power transmission is performed smoothly. With these mechanisms, power transmission loss is reduced to zero, and an energy saving effect can be exhibited. FIG. 2 is a sectional view showing the detailed structure of the power transmission section of the fluid coupling shown in FIG. 1 incorporating the multi-plate clutch.
As shown in FIG. 2, the clutch chamber 13 is fixed to the fluid coupling housing 20. Further, a clutch hub 21 is fixed to the water wheel 5. The clutch chamber 13 holds the driving-side friction plate 7 movably in the axial direction of the drive shaft 1, and the clutch hub 21 holds the driven-side friction plate 12 movably in the axial direction of the driven shaft 9. Have been.
That is, although the driving-side friction plate 7 rotates integrally with the clutch chamber 13, it can move in the axial direction with respect to the clutch chamber 13, and the driven-side friction plate 12 rotates integrally with the clutch hub 21. 21 is movable in the axial direction. A clutch piston 11 is disposed in the clutch chamber 13. When hydraulic oil is supplied to the cylinder chamber 10 in the clutch chamber 13, centrifugal pressure is generated in the cylinder chamber 10 as described above. Then, the driving-side friction plate 7 is pressed against the driven-side friction plate 12, and the multi-plate clutch is engaged. Therefore, the drive shaft 1 and the driven shaft 9 rotate at the same rotational speed without slip. A radial bearing 31 is interposed between the clutch chamber 13 and the clutch hub 21. Reference numeral 23 denotes a clutch oil supply port, and reference numeral 24 denotes a fluid coupling supply port. In addition, a circuit having a fluid coupling working oil minimum oil amount setting orifice 32 and a fluid coupling working oil minimum oil amount switching valve 33 is additionally connected in parallel with the fluid coupling working oil switching valve 15. In the fluid coupling shown in FIG. 1, when the clutch switching valve 14 is opened and the clutch is engaged to perform a direct connection operation between the drive shaft 1 and the driven shaft 9, the fluid in the fluid coupling during the full speed operation is used. There is a problem that power for mixing and stirring is consumed. Therefore, in order to further enhance the energy saving effect, there is a demand for energy saving measures from the entire configuration of the fluid coupling including the clutch. Therefore, in the present invention, during operation of the fluid coupling including the above-described multi-plate clutch,
After the drive shaft 1 and the driven shaft 9 are directly connected, the hydraulic oil present in the hydraulic coupling hydraulic oil chamber is extracted to reduce the mixing and stirring power of the fluid in the hydraulic coupling during full-speed operation, thereby further improving the energy saving effect. Is to try. That is, in the present invention, after the clutch operates and power is transmitted, the supply of hydraulic oil into the fluid coupling housing 20 is stopped, and the fluid coupling housing 20 is stopped.
The hydraulic oil in the fluid coupling is discharged, the power transmission from the fluid coupling portion is eliminated, the power is transmitted only by the clutch, and the mixing and stirring power by the fluid in the fluid coupling is eliminated. of course,
At that time, since all the power is applied to the clutch, the frictional force for stopping the slip between the clutches is increased, and the structure is structurally strong. In this way, even if the drive shaft 4 and the driven shaft 9 are rotating at the same rotational speed, the pumping blade 4 and the water turbine blade 5 are filled and actuated by pressure imbalance. Loss caused by the flow of oil can be eliminated, and at the same time, unbalanced vibration due to the presence of fluid inside both blades can be eliminated. Since the fluid in the fluid coupling hydraulic oil chamber formed by the pumping blade 4, the water wheel 5 and the fluid coupling housing 20 gradually decreases, the amount of increase in the torque applied to the clutch is not abrupt in time. Transition smoothly. After the hydraulic fluid runs out of the fluid coupling hydraulic oil chamber,
Since the hydraulic oil switching valve 15 for supplying hydraulic oil for supplying the hydraulic oil into the fluid coupling housing 20 is closed, the flow rate of the hydraulic pump 16 for supplying the hydraulic oil is reduced, and the power consumed by the pump is further reduced. Energy saving. At this time, the fluid coupling operating oil minimum oil amount switching valve 33 is also closed. FIG. 3 is a system diagram showing a second embodiment of the fluid coupling of the present invention. In the second embodiment, a circuit having a fluid coupling working oil minimum oil amount setting orifice 32 is additionally connected in parallel with the fluid coupling working oil switching valve 15. The difference from the embodiment shown in FIG. 1 is that the fluid coupling operating oil minimum oil amount switching valve 33 is omitted.
In the second embodiment, the minimum oil amount setting orifice 3
By adjusting the balance between the supply flow rate of No. 2 and the discharge flow rate of the fluid-coupling discharge nozzle 6, it is possible to prevent the oil level from being applied to both the pump action blade 4 and the water turbine action blade 5.
By closing the fluid coupling hydraulic oil switching valve 15 to cut off the supply of the fluid coupling hydraulic oil, the same effect as that of the fluid coupling shown in FIG. 1 can be obtained. That is, if the hydraulic oil remaining in the fluid coupling hydraulic oil chamber is discharged so that the oil level of the hydraulic oil does not reach the pump operation blade and the water turbine operation blade, the mixing and stirring power by the fluid in the fluid coupling during full speed operation is obtained. Can be reduced, and the energy saving effect can be further increased. Next, an example of an operation pattern of the fluid coupling configured as shown in FIG. 1 or FIG. 3 will be described with reference to FIG. In FIG. 4, the horizontal axis represents time, and the vertical axis represents rotation speed. FIG. 4 shows that the prime mover is rotating at the rated rotational speed (input rotational speed), and that the rotational speed of the driven machine changes depending on the state of the fluid coupling and the clutch. FIG. 4 shows the open / closed state of the quick switching valve (the hydraulic oil switching valve 15 for fluid coupling).
The open / close state of the / OFF valve (clutch switching valve 14) is shown. The prime mover is rotating at the rated rotation speed (input rotation speed), and the quick switching valve (hydraulic oil switching valve 1 for fluid coupling)
When (5) is closed, the hydraulic oil amount specified by the hydraulic coupling hydraulic oil minimum oil amount setting orifice 32 is supplied to the hydraulic coupling operating chamber formed by the pump operating blade 4, the water turbine operating blade 5, and the hydraulic coupling housing 20. Then, the rotational speed of the driven machine becomes the minimum rotational speed as shown in FIG. At this time, in the embodiment shown in FIG. 1, the fluid coupling operating oil minimum oil amount switching valve 33 is open. Next, the quick switching valve is opened and the hydraulic pump 16
To supply the hydraulic oil to the pumping blade 4 at substantially no pressure to about 0.2 MPa. Then, the fluid coupling is refueled and the rotation speed of the driven machine is rapidly increased to the maximum rotation speed including slippage due to the fluid coupling (about 5 seconds).
Within). Next, when the clutch ON / OFF valve (clutch switching valve 14) is opened and hydraulic oil is supplied to the clutch, the multi-plate clutch operates to increase the rotation speed of the driven machine.
Then, as shown in FIG. 4, the prime mover and the driven machine immediately rotate at the same rotational speed without slip to transmit power.
In this state, the fluid coupling and the clutch operate to transmit power. Thereafter, the hydraulic fluid switching valve 15 for the fluid coupling is closed, and power is transmitted only by the clutch. When power is transmitted only by this clutch, the hydraulic oil present in the fluid coupling hydraulic oil chamber is extracted to reduce the mixing and stirring power by the fluid in the fluid coupling during full-speed operation, further increasing the energy saving effect. I have. In order to close the hydraulic coupling operating oil switching valve 15 that supplies hydraulic oil into the fluid coupling housing 20, the flow rate of the hydraulic oil supply hydraulic pump 16 is defined by the hydraulic coupling hydraulic oil minimum oil amount setting orifice 32. The flow rate is reduced, and the power consumed by the pump is reduced, further saving energy. In the case of FIG. 1, the fluid coupling operating oil minimum oil amount switching valve 33 is closed. After performing the power transmission only by the clutch for a predetermined time, the rapid switching valve is opened again, and the power transmission by the fluid coupling and the clutch is performed for a predetermined time. Then, close the clutch ON / OFF valve,
Switch to power transmission by fluid coupling only. In the power transmission using only the fluid coupling, the rotational speed of the driven machine gradually decreases, and is eventually reduced to the maximum rotational speed including slippage due to the fluid coupling. Next, when the quick switching valve is closed, the rotation speed (output rotation speed) of the driven machine is reduced,
Eventually the speed is reduced to the minimum rotational speed. Thereby, Ta
One cycle of sec (second) ends. As described above, the fluid coupling according to the present invention can easily start and stop a large-sized rotating machine as well as rapidly perform a rapid acceleration operation and a maximum rotation speed (specified rotation speed).
After starting the large rotating machine and reaching the specified speed, despite the two-step shifting operation with the minimum rotation speed and the minimum rotation speed, the drive shaft and the driven shaft of the fluid coupling are mechanically connected to rotate the rotation. And energy saving can be achieved. According to the present invention, the power loss of the fluid stirring in the fluid coupling main body is reduced, and the power transmission efficiency of the entire fluid coupling system is improved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a system diagram showing an overall system of a first embodiment of a fluid coupling according to the present invention. FIG. 2 is a sectional view showing a detailed structure of a power transmission unit of the fluid coupling shown in FIG. FIG. 3 is a system diagram showing a second embodiment of the fluid coupling of the present invention. FIG. 4 is a diagram showing an example of an operation pattern of the fluid coupling of the present invention. [Description of Signs] 1 Drive shaft 2, 31 Radial bearing 3 Thrust bearing 4 Pump operating blade (impeller) 5 Water turbine operating blade (runner) 6 Hydraulic oil discharge nozzle 7 Drive side friction plate 8 Clutch hydraulic oil discharge nozzle 9 Driven shaft 10 Cylinder chamber 11 Clutch piston 12 Driven friction plate 13 Clutch chamber 14 Clutch switching valve 15 Fluid coupling hydraulic oil switching valve 16 Hydraulic pump 17 Fluid coupling lubrication pipe 18 Clutch lubrication pipe 19 Release valve 20 Fluid coupling housing 21 Clutch hub 22 Fixed plate 23 Clutch oil supply port 24 Fluid coupling supply port 25 Oil return pipe 30 Fluid coupling case 32 Fluid coupling minimum hydraulic oil setting orifice 33 Fluid coupling hydraulic minimum oil switching valve

   ────────────────────────────────────────────────── ─── Continuation of front page    (72) Inventor Kazuo Hattori             11-1 Haneda Asahimachi, Ota-ku, Tokyo             EBARA CORPORATION (72) Inventor Taiyo Ogata             11-1 Haneda Asahimachi, Ota-ku, Tokyo             EBARA CORPORATION (72) Inventor Kazuhiko Sugiyama             11-1 Haneda Asahimachi, Ota-ku, Tokyo             EBARA CORPORATION

Claims (1)

Claims: 1. A pumping blade provided on a drive shaft driven by a prime mover uses a fluid as a medium for power transmission to rotate a water turbine operating blade provided on a driven shaft by kinetic energy given to the fluid. A clutch provided between a drive shaft side and a driven shaft side, and in a state where the pumping blade and the water turbine blade are filled with oil to transmit rotational power, the clutch is provided. After the clutch is actuated, the hydraulic oil remaining in the fluid coupling hydraulic oil chamber is removed, or the fluid coupling is A fluid coupling characterized in that the hydraulic oil remaining in the hydraulic oil chamber is discharged so that the oil level of the hydraulic oil does not reach the pump operating blade and the water turbine operating blade.