JPS58221023A - Variable speed fluid coupling - Google Patents

Abstract

PURPOSE:To make it possible to adjust the operating position of a flow adjusting valve, by adjusting a needle valve for regulating the discharge pressure of a Westco pump for feed-back so that the pressure of feed-back operation is changed. CONSTITUTION:When the rotational speed of the output shaft 9 is lowered, the discharge pressure of a Westco pump is made large so that a spool 21 is pushed up by the actuation of a pressure detecting device 28 for opening a flow adjusting valve, resulting in increasing the supply volume of working fluid into an impeller 5, and therefore, the rotational speed of the output shaft 9 is raised. On the contrary, when the rotational speed of the output shaft 9 is raised, the spool 21 is moved downward so that the open degree of the flow adjusting valve is reduced for decreasing the inlet flow into an impeller 5, and therefore, the rotational speed of the output shaft 9 is lowered, thereby automatic control is made such that the control pressure of a driven machine becomes a predetermined value.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a fluid coupling, in particular, a runner installed on an input shaft (a runner is rotatably disposed within a single-digit impeller, and the runner is attached to an output shaft, and a pump for supplying working fluid is used to connect a runner to the impeller). While supplying working fluid to the impeller, the rotation of the input shaft is transmitted to the output shaft, and the supply amount of the working fluid is controlled by a flow control valve, and the supply amount is continuously supplied from a small outlet hole provided on the outer periphery of the impeller. 1. Discharge the internal driftwood of the impeller and runner by making the current larger or smaller than the current. This invention relates to an i'iJ variable speed fluid coupling that controls the rotational speed of an output shaft by freely adjusting the position of the I-+ surface from the shaft center.

In the above-mentioned flits, the operation t is
The supply amount of the IT body 2- is determined based on the rotational speed of the output shaft and the load-side state variables of a driven machine such as a pump or blower rotationally driven by the output shaft, such as discharge pressure, flow rate, suction water tank water level, discharge water tank water level, etc. It is controlled in accordance with a control pressure signal (hereinafter simply referred to as driven machine control pressure 6) issued in response to a state quantity. Then, in order to detect and feedbank the control pressure signal of the driven machine and the rotational speed of the output shaft, the flow rate adjustment device is controlled by the discharge pressure signal from the feedback pump attached to the output shaft. It looks like this.

- Conventionally, in this type of fluid coupling, the feedback pump is constituted by a centrifugal pump, the discharge pressure of which moves a diaphragm to actuate the flow control valve (1) and causes the flow to flow through an orifice. There is.

However, since this is an orifice or fixed type and the flow rate from the orifice cannot be adjusted, the feedback operating pressure cannot be adjusted, and the position of the flow rate control valve cannot be arbitrarily set or adjusted. = Also, in the conventional fluid coupling mentioned above, the spring that supports the diaphragm that receives the control pressure of the driven machine from the back side cannot be adjusted, so it has the disadvantage that it cannot be adjusted to correspond to changes in the set control pressure of the driven machine. .

The present invention aims to overcome the drawbacks of the conventional fluid couplings described above.
This method adjusts the discharge pressure of the Esco pump for the feed bank by adjusting the needle valve, changes the feedback operation pressure, and allows the operating position of the flow control valve to be set or adjusted so that it is always in the optimal state. It is an object of the present invention to provide a variable speed fluid coupling that can adjust the pressure detection device to the most operable state by controlling the operation, and even when the set value of the control pressure of the driven machine is changed. This is the purpose.

The present invention has a runner rotatably disposed in an impeller mounted on an input shaft, and the runner is attached to an output shaft, and a working fluid supply pump rotationally driven by the input shaft is used to supply a working fluid to the impeller. The rotation of the human-powered shaft is transmitted to the output shaft by supplying working fluid to the output shaft, and a load-side state quantity signal corresponding to the load-side state of the driven machine rotationally driven by the output shaft is also output. A flow control valve is controlled by the discharge pressure from a feedback pump attached to the shaft, and the supply amount of the working fluid is adjusted, thereby adjusting the position of the free surface of the internal fluid of the impeller and the runner from the center of the shaft. In a fluid coupling that automatically controls the rotational speed of the output shaft, the feedback pump is constituted by a Wesco pump, and its discharge pressure moves the spool to operate the flow rate control valve and adjust the pressure of the discharged fluid. The flow control valve can be adjusted by a needle valve, and the load-side state quantity signal of the driven machine is converted into pressure, and a flexible pressure receiver such as a diaphragm or bellows is operated to receive the pressure, and the flow rate adjustment valve is actuated via an appropriate transmission mechanism. The variable speed fluid coupling is characterized in that the flexible pressure receiver is supported by an adjustable back pressure spring.

An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, 1 is a main body case 5-sink, and an input shaft 3 is supported by a bearing 2 at one end thereof. An impeller 5 is integrally attached to the right inner end of the input shaft 3 via a 7 flange 4, and a sleeve 6 is fixed to the impeller 5 and is inserted into the main body casing 1. It is supported by a bearing 8 of a bearing body 7 provided in the bearing body 7. Therefore, input shaft 3.7 langes 4, impeller 5
, and sleeve 6 is reliably supported by bearings 2 and 8 which are spaced apart from each other with a sufficiently large distance.

Reference numeral 9 denotes an output shaft, which is supported by a bearing 10 on the other end side of the main body casing 1, and its left inner end is supported by a bearing 11 provided in the flange 4, and is connected to the output side rotating body. is also reliably supported by the bearings 10 and 11 provided at a sufficiently large interval, and in combination with the above-mentioned method of supporting the input side rotating body,
The axial length of the fluid coupling is reduced. 12 is a runner, which is accommodated in the output shaft 9, and
”1 It is designed to be able to rotate freely within the impeller 5.

The lower part of the bearing body 7 is open, allowing the left and right oil tanks 13 and 14 to communicate with each other. Further, a centrifugal pump 15 for supplying working fluid is attached to the lower part of the bearing body 7 from below. The centrifugal pump 15 includes a sleeve 6 that rotates together with the input shaft 3 and impeller 5.
It is designed to be rotationally driven via an intermediate gear 17 by a timing gear 16 attached to the intermediate gear 17 . Reference numeral 18 denotes a bearing bushing, which rotatably supports the intermediate gear 17 and is fitted into the bearing body 7.

As is clear from FIG.
0a has been contacted. The flow rate regulating device 20 is constructed such that a casing as shown in FIG. 3 is attached to a bearing body 7, and the bearing body 7 also functions as one side wall of the device. A spool chamber 20b is formed in the flow rate adjustment device 20, and a flow rate adjustment valve is configured by moving the spool 21 up and down within the spool chamber 20b. As is clear from FIG. 1, the spool chamber 20b is the outflow chamber 20.
c, it communicates with the right side chamber of the impeller 5 through a flow path 6a formed between the sleeve 6 and the output shaft 9, and further a flow path 12a formed inside the boss portion of the runner 12. It is communicated with the left side chamber of the impeller 5 through the impeller 5.

22 is a Wesco pump for feedback of the output shaft 9, and its impeller 22a is attached to the output shaft 9. A suction passage 22b and a discharge passage 22c are formed in the casing of the Wesco pump 22, as shown in FIG.
The discharge passage 22c also communicates with the pool chamber 2dd. In particular, no suction casing is required in the axial direction. Further, the suction of the Wesco pump 22 is operated not in a suction state but in a pushing state. A spool 23 is housed in the spool chamber 2Od so as to move up and down. The spool 23 is urged downward by a return spring 24. The spool chamber 20d is connected to the inflow chamber 20a by a communication passage 20e, and the pressure fluid in the spool chamber 20d is controlled by a needle valve 25. 8- An appropriate amount is allowed to flow out into the inflow chamber 2Oa, and the pressure used for the feedback operation in the pool chamber 2Od can be appropriately set for the return spring 24.

The upper ends of the spools 21 and 23 are pivotally connected to both ends of a lever 26, and the lower end of a rod 27 is pivotally connected to the middle part of the lever 26. The upper end of the rod 27 is connected to a pressure sensing device 28.

As is clear from FIG. 5, the pressure detection device 28 is provided with a diaphragm 29, and the driven device 8!, such as a pump or blower, is provided with a diaphragm 29. (not shown) is suppressed in response to a control pressure (for example, the pressure of fluid discharged from a driven machine) corresponding to a load-side state quantity. The diaphragm 2
An operating rod 31 is attached to the back of 9 via a rod 30 (1
I'm being kicked.

A back pressure spring 33 is interposed between the operating rod 31 and the supporting rod 32, and by setting the supporting rod 32 to an appropriate position with an adjustment screw 34, the initial position of the operating rod 31 can be adjusted. 9- It is now possible to set the reinforcement. One end of an I-shaped link 35 is pivotally connected to the operating rod 31, and the other end of the I-shaped link 35 is pivotally connected to one end of a lever 37 via a rod 36. There is. The other end of the lever 37 is pivotally attached to the upper end of the rod 27, and its intermediate portion is pivotally supported by an adjusting screw 38. The adjustment screw 38 is set at an appropriate position by a handle 39, and even when control based on the control pressure of the driven machine is not performed, the pivot point 37I between the rod 36 and the lever 37 is used as the fulcrum and the waist Neshi 38 and lever 3
It is possible to manually set the position of the pivot point 37a with respect to 7 and perform control only by feedback control of the output shaft rotation speed based on the discharge pressure of the Wesco pump 22. Also,
The diaphragm 29 of the pressure sensing device 28 may be replaced with a bellows 29' as shown in FIG.

In addition to discharge pressure, load state quantities such as discharge flow rate, suction water tank water level, and discharge water tank water level are detected as state quantities on the load side of the driven machine.
Alternatively, it may be converted into force and applied to the operating rod 31. In this way, control can be performed to keep these load-side state quantities constant. A spirally wound cooling pipe 40 is disposed in the oil tank 13 at the bottom of the main body casing 1, and the hydraulic oil is cooled by an external refrigerant flowing through the cooling pipe 40.

Next, the operation of the above embodiment will be explained.

The input shaft 3 is connected to the input shaft 3 by an appropriate prime mover (not shown) such as an electric motor.
The centrifugal pump 1-5 is operated via the opening gear 17 by the timing gear 16 rotating integrally with the impeller 5. When the centrifugal pump 15 begins to rotate, the working fluid pushed up thereby flows into the inflow chamber 20a of the flow rate adjustment device 20 through the arrangement qf19. At the start of operation, the fulcrum 26a of the lever 26 is in the neutral position, and the pivot point 26b is pushed down by the return spring 24, so the spool 21 is positioned on three sides and the flow rate control valve is open. Therefore, a part of the working fluid that has entered the inflow chamber 20a as described above passes through the spool chamber 2Ob, flows into the right side chamber of the impeller 5 from the outflow chamber 20c and the passage 6a, and also Impeller 5 via passage 12a
Flows into the left side of the room.

Since the amount of working fluid supplied is greater than the amount that is continuously discharged from the small discharge hole 43 provided on the outer periphery of the impeller 5, the working fluid gradually accumulates inside the runner 12 and the free surface approaches the central axis ( =1<position, and the rotational speed of the runner 12 is increased.

The working fluid that has entered the impeller 5 rotates the rotationally inner runner 12 together with the impeller 5, thereby rotating the output shaft 9 integrated therewith. When the output shaft 9 rotates,
Wesco pump 22 starts to operate, and its suction passage 22b
A part of the working fluid in the inflow chamber 2Oa is sucked in from the inflow chamber 2Oa,
A working fluid having a pressure corresponding to the number of strokes of the output shaft 9 is sent into the spool chamber 20d from the discharge passage 22c. The original pressure that has entered the spool chamber 20d is appropriately regulated by the needle valve 25 and flows out into the inflow chamber 2On through the communication path 20e.

While the rotational speed of the output shaft 9 is low, the control pressure of the driven drive 12 is low, so the force pressing the diamond 7 arm 29 against the back pressure spring 33 is weak, and the rod 27, i.e. The position of the fulcrum 26a of the lever 26 hardly changes, and the discharge pressure of the Wesco pump 22 is small, so the spool 23 in the spool chamber 2Od is hardly moved, and the pivot of the lever 26 is Point 26b also remains at the same position. Therefore, the spool 21 remains fully open and continues to supply working fluid into the impeller 5.

When the control pressure (for example, discharge pressure) of the driven machine increases and the control pressure increases, the diaphragm 2 of the pressure detection device 28
9 is pushed to the left in FIG. 2, causing the operating rod 31 to move to the left against the back pressure spring 33.

When the operating rod 31 moves to the left, the L-shaped sink 35 moves to the fulcrum 35.
Rotate clockwise around point a and lift the rod 36 upwards. When the rod 36 moves upward, the lever 37 rotates clockwise about the pivot point 37a with the adjustment screw 38, pushing the rod 27 downward, as is clear from FIG. As the rod 27 moves downward, the lever 26
The fulcrum 26a13- moves downward.

When the fulcrum 26a of the lever 26 moves downward, the lever 26 is rotated to the left, so the spool 21 is pushed down and the amount of working fluid flowing into the spool chamber 20b from the inflow chamber 20a is throttled. When the amount of flow into the spool chamber 2Ob is reduced, an increase in the amount of working fluid in the impeller 5 is suppressed, and an increase in the rotational speed of the output shaft 9 is suppressed.

Also, when the rotational speed of the output shaft 9 is increasing, the output shaft 9
Since the discharge pressure of the Wesco pump 22, that is, the pressure inside the spool chamber 20d increases as the rotation speed increases, the spool 23 is pushed up by overcoming the return spring 24, and the position of the pivot point 26b of the lever 26 is raised. Then, the amount of working fluid flowing into the spool chamber 20b from the inflow chamber 20a is throttled. This helps to suppress an increase in the rotational speed of the output shaft 9.

As the amount of inflow into the spool chamber 201], that is, the amount of supply into the impeller 5, decreases, the amount of water that flows into the impeller 5 approaches a state where it is continuously discharged from the small discharge hole 43 provided on the outer periphery of the impeller 5, and eventually the amount of supply decreases. The increase in rotational speed stops when the amount of discharge is balanced.

Furthermore, when the supply amount decreases beyond the equilibrium state and becomes smaller than the discharge amount, the amount of working fluid in the impeller 5 begins to decrease and the rotational speed of the output shaft 9 begins to decrease.

When the rotational speed of the output shaft 9 decreases, the discharge pressure of the Unisph pump 22, that is, the pressure inside the spool chamber 20d decreases, and the spool 23 is pushed down by the return spring 24, causing the lever 26 to pivot. point 26
Go down to position b.

Then, as this approaches, the control pressure of the driven machine decreases, and the operating rod 31 is pushed back to the right in FIG. 2 by the back pressure spring 33.
Rotate the L-shaped sink 35 to the left and lower the rod 36.

When the rod 36 descends, the lever 37 rotates to the left to lift the rod 27, and the fulcrum 26a of the lever 26 moves in three directions.

As shown in Figure 2, when the rotational speed of the output shaft 9 decreases, the rotational speed of the output shaft 9 decreases.
One point 26b goes down first, and the fulcrum 26a of the lever 26 goes up following this, so the lever 2G rotates clockwise and lifts the spool 23 upwards, reducing the amount of inflow into the spool chamber 20b, that is, the amount of inflow into the impeller 5. is increased, and the rotational speed of the output shaft 9 is increased again.

As described above, when the rotation of the output shaft 9 decreases, the spool 21 is pushed up by the action of the Wesco pump 22 and the pressure detection device 28, and the flow control valve is opened, and the working fluid flows into the impeller 5. As the supply amount increases, the rotational speed of the output shaft 9 increases. Conversely, when the rotational speed of the output shaft 9 increases by 1, the spool 21 is moved downward and the opening degree of the flow adjustment valve becomes smaller, the amount of inflow into the impeller 5 decreases, and the flow rate of the output shaft 9 decreases. The rotational speed decreases and the control pressure of the driven machine is automatically controlled to the set value.

In the above embodiment, since the Wesco pump 22 is used to determine the opening of the control valve spool 21 at the beginning of operation, the pressure in the feedback spool chamber 20d is lower than that of the conventional one due to the change in the relief amount of the needle valve 25. compared to centrifugal pumps. When the Wesco pump 22 is used, the cut-off discharge pressure is approximately 2 to 2.5 times higher than that of a centrifugal pump with the same impeller outer diameter. Therefore, a wide range of pressure can be used, and by utilizing this, the feedback spool 23 for the rotational speed on the driven machine side can be used.
It is easy to return the position of the spring 24 and set it so that an appropriate stroke can be obtained between full-speed rotation and low-speed rotation by countering the action of the spring 24.

The stroke of the feedback spool 23 is directly reversed by the lever 26 to the stroke of the regulating valve spool 21, thereby contributing to the regulating action. Therefore, once the two-dollar valve 25 is initially set, no adjustment is required thereafter. By adjusting the initial setting of the needle valve 25 according to the type of working fluid, temperature, discharge set pressure, set rotation speed, etc. so that the stroke position of the spool 23 is appropriate, it is an advantage that has a wide range of applications. control can be performed.

Since the present invention is configured as described above, it is possible to freely adjust the setting position of the flow rate control valve by adjusting the pressure for feedback control, and also to adjust the load side state such as the discharge pressure of the driven machine. Even if the set value is changed, the pressure detection device is adjusted accordingly, and the position of the flow rate control valve is always set or adjusted to the optimum state, thereby ensuring reliable and highly accurate operation control. .

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view showing one embodiment of the variable speed fluid coupling of the present invention, Fig. 2 is a transverse sectional view taken along line 1-1 in Fig. 1, and Fig. 3 is a case of the flow rate adjustment device. 4 is an enlarged view showing the case of the Wesco pump, FIG. 5 is an enlarged sectional view showing the pressure detection device, and FIG. 6 is a partial sectional view showing another embodiment of the pressure detection device. It is. 1...Body casing 2...Bearing 3...Input shaft 4...7 Lange...Impeller
6... Sleeve 6a... Channel 7... Bearing body 8... Bearing 9... Output shaft 10.
11...Bearing 12...Runner 13.14...
・Oil tank 15... Centrifugal pump 16... Timing gear 17... Intermediate gear 18... Bearing bushing
19... Piping 20... Flow rate adjustment device 20a...
Inflow chamber 201)... Spool chamber 2'Oc... Outflow chamber 20d... Spool chamber 20e... Communication path 21.
...Spool 22': ...Wesco pump 22a
... Impeller 22b... Suction passage 22c...
Discharge passage 23...Spool 24...Return spring
25... Needle valve 26... Lever 26
a...Fully point 26b...Pivot point 27...Rod-28...Pressure detection device 29...Guiya 7 ram 29'...Bello 30...Rod 31...
Operating rod 32...Support rod 33...Back pressure spring
34...Adjustment screw 35...L type sink 35
a...Fully point 36...Port 37...Lever 37a, 37b...Pivot point 38...Adjustment screw 3
9... Handle 40... Cooling pipe 43... Discharge hole 19-

Claims (1)

[Claims] 1. A runner is rotatably disposed in an impeller mounted on an input shaft, and the runner is attached to an output shaft,
A working fluid supply pump rotationally driven by the input shaft supplies working fluid into the impeller to transmit the rotation of the input shaft to the output shaft, and also to transmit the rotation of the input shaft to the output shaft. The flow control valve is controlled by the load-side state quantity signal corresponding to the state and the discharge pressure from the single-digit feed bank pump attached to the outlet valve shaft, and the supply amount of the working fluid is adjusted. (inside the impeller and runner) In a fluid coupling that automatically controls the rotational speed of the output shaft while adjusting the position of the free surface of the flat body from the axis center; is constituted by a Wesco pump, and its discharge pressure moves a spool to operate a flow control valve, and the pressure of the discharge fluid can be adjusted by a neat valve. Converts the load-side state quantity signal of the driven machine into pressure, causes a flexible pressure receiver such as a guyafram or bellows to receive the pressure, and operates the flow rate control valve via a transmission mechanism as appropriate, and the flexible pressure receiver can be adjusted. A variable speed fluid coupling characterized by being supported by a back pressure spring.