Variable-ratio quick coupling

Abstract

The application discloses a variable-torque quick coupling and belongs to the technical field of pumped storage units. The variable-torque quick coupling is provided with a machine shell and a water pump shaft. A hollow motor shaft is arranged in the machine shell. The hollow motor shaft is characterized in that a driving pump wheel and a driving main gear are arranged on the hollow motor shaft, a driven runner and a driven secondary gear are arranged on the water pump shaft, an intermediate gear is arranged between the driving main gear and the driven secondary gear, a piston rod is arranged in the hollow motor shaft, a servomotor is fixed in a ring cavity formed by the piston rod and the hollow motor shaft, the intermediate gear moves up and down under the action of the servomotor, and the intermediate gear is connected with the driving main gear and the driven secondary gear through gear meshing. The application can realize low-torque and low-load starting without reducing the rotating speed of the motor, reducing the rotating speed of the water pump shaft through the coupling, and without stopping operation during working condition conversion. The application can effectively save the conversion time and quickly respond to the demand of the power grid.

Description

Technical Field

[0001] This invention relates to the field of pumped storage unit technology, and in particular to a torque-changing fast coupling. Background Technology

[0002] In a pumped-storage hydroelectric unit, the turbine and pump are two operating modes of the same equipment: the turbine generates electricity, and the pump pumps pump water. Similarly, the generator and motor are two operating modes of the same equipment: the generator supplies power to the grid, and the motor consumes power from the grid.

[0003] Pumped storage units have high starting torque for their pumps, often employing SFC (Static Variable Frequency) or variable frequency drive (VFD) starting methods to reduce this torque. Using electrical methods to achieve low-speed starts and gradually increase to synchronous speed is expensive, and the reliability is affected by the stability of the electrical equipment. To reduce the generator load, the unit must be shut down and restarted before switching between turbine and pump operating modes, resulting in a lengthy transition time.

[0004] Chinese patent document CN214330788U, published on October 1, 2021, discloses a coupling device for a modular through-flow propeller turbine generator set. The device is characterized by comprising a linkage rod, a telescopic joint, a telescopic connecting ring, two linkage shafts, a generator connector, and a turbine main shaft speed increaser. The generator connector is located above the turbine main shaft speed increaser. Both the generator connector and the turbine main shaft speed increaser are fixedly connected to the plant building. The linkage rod is located between the generator connector and the turbine main shaft speed increaser. One end of the linkage rod is fixedly connected to the generator connector, and the other end is fixedly connected to the turbine main shaft speed increaser. The telescopic joint is located between the linkage rod and the generator connector. At the connection point between the devices, one end of the telescopic device is fixedly connected to the linkage rod, and the other end of the telescopic device is fixedly connected to the generator connector. The telescopic connecting ring is located at the connection point between the telescopic device and the linkage rod, with one end of the telescopic connecting ring fixedly connected to the telescopic device and the other end fixedly connected to the linkage rod. The two linkage shafts are located at the upper and lower ends of the linkage rod, respectively, and both linkage shafts are fixedly connected to the linkage rod. One of the linkage shafts is fixedly connected to the generator connector, and the other linkage shaft is fixedly connected to the turbine main shaft speed increaser. Each linkage shaft is also provided with a protective sleeve, which is located on the outside of the linkage shaft and is fixedly connected to the linkage shaft.

[0005] The coupling device disclosed in this patent document for a modular axial-flow propeller turbine generator set reduces the concentricity and elevation position errors between the generator set shaft and the turbine speed increaser shaft, making the operation of the generator set and turbine set smoother, more stable, safer, and more reliable, and installation more convenient and easier. However, when changing the turbine operating condition and the pump operating condition, it is still necessary to first shut down the unit and then restart it to switch operating states. The switching time is relatively long and cannot achieve rapid response to grid demands. Summary of the Invention

[0006] To overcome the shortcomings of the prior art, this invention provides a torque-changing quick coupling. This invention eliminates the need to reduce the motor speed, and reduces the pump shaft speed through the coupling to achieve low-torque, low-load start-up. No shutdown operation is required during operating condition changes, which can effectively save switching time and quickly respond to power grid demands.

[0007] This invention is achieved through the following technical solution:

[0008] A torque-changing quick coupling includes a housing and a water pump shaft. A hollow motor shaft is disposed within the housing. The hollow motor shaft is characterized by: a drive pump wheel and a drive main gear mounted on the hollow motor shaft; a driven wheel and a driven secondary gear mounted on the water pump shaft; an intermediate gear disposed between the drive main gear and the driven secondary gear; a piston rod disposed within the hollow motor shaft; a servo drive fixed within the annular cavity formed by the piston rod and the hollow motor shaft; the intermediate gear moving up and down under the action of the servo drive; and the intermediate gear being connected to the drive main gear and the driven secondary gear respectively through gear meshing.

[0009] The housing is equipped with movable guide vanes for adjusting the flow rate.

[0010] The casing has an inlet and an outlet, with the inlet located above the outlet and the movable guide vane located on one side of the inlet.

[0011] The drive pump wheel is rigidly connected to the hollow motor shaft, and the drive pump wheel is used to pressurize the incoming water flow.

[0012] The movable guide vane is used to control the magnitude of the torque transmitted asynchronously, and to lock the flow rate and the synchronous speed.

[0013] The drive main gear is rigidly connected to the hollow motor shaft, and the drive main gear is used to transmit torque after synchronizing the rotation speed.

[0014] The driven impeller is used to convert the high-pressure water flow input to the driving pump wheel and output torque to the pump shaft, driving the pump shaft from a standstill to synchronous speed.

[0015] The driven pair gear is used to transmit torque through gear meshing after synchronizing the rotational speed.

[0016] The drive main gear is located below the drive pump wheel.

[0017] The driven pair gear is located below the driven wheel.

[0018] The beneficial effects of this invention are mainly reflected in the following aspects:

[0019] 1. This invention comprises a hollow motor shaft with a drive pump wheel and a drive main gear, a driven wheel and a driven secondary gear on the pump shaft, an intermediate gear between the drive main gear and the driven secondary gear, a piston rod inside the hollow motor shaft, and a servo drive fixed in the annular cavity formed by the piston rod and the hollow motor shaft. The intermediate gear moves up and down under the action of the servo drive. The intermediate gear is connected to the drive main gear and the driven secondary gear through gear meshing. Compared with existing variable frequency starting equipment and SFC starting methods, which reduce the motor speed to reduce the starting torque and reduce the motor load, this invention eliminates the need to reduce the motor speed. The pump shaft speed is reduced through a coupling to achieve low torque and low load starting. No shutdown operation is required during operation mode switching, which can effectively save switching time and quickly respond to grid demand.

[0020] 2. In this invention, a movable guide vane for adjusting the flow rate is provided inside the casing. By adjusting the opening of the movable guide vane, the torque transmitted from the driving pump wheel to the driven impeller is controlled, thereby controlling the motor load and the starting speed of the water pump.

[0021] 3. In this invention, the casing has an inlet and an outlet, with the inlet located above the outlet and the movable guide vane located on one side of the inlet. The structure is simple and facilitates the rapid start-up of the subsequent water pump.

[0022] 4. In this invention, the drive pump wheel is rigidly connected to the hollow motor shaft. The drive pump wheel is used to pressurize the incoming water flow. By driving the pump wheel, the water flow entering the coupling is transformed into a high-pressure water flow, which facilitates the synchronous rotation of the driven wheel.

[0023] 5. In this invention, the movable guide vane is used to control the magnitude of the torque transmitted asynchronously, and to lock the flow rate and the synchronous speed. By setting the movable guide vane, the starting speed of the water pump can be conveniently controlled.

[0024] 6. This invention enables pumped storage units to switch between turbine and pump operating modes without shutting down the unit, using a variable torque method. The entire switching process is achieved through a mechanical-hydraulic connection, resulting in high structural reliability and rapid mode switching.

[0025] 7. This invention is not only suitable for multi-condition switching of traditional low-head Francis-type two-unit pumped storage units, but also for high-head and ultra-high-head three-unit pumped storage units, making it highly applicable.

[0026] 8. Since this invention does not require frequency converter starting equipment or SFC starting equipment and is a purely mechanical operation, it can effectively reduce costs and has high reliability. Attached Figure Description

[0027] The present invention will now be further described in detail with reference to the accompanying drawings and specific embodiments, wherein:

[0028] Figure 1 This is a schematic diagram of the structure of the present invention;

[0029] Figure 2 This is a plan view of the present invention;

[0030] The markings in the diagram are: 1. Casing, 2. Movable guide vane, 3. Drive pump wheel, 4. Driven impeller, 5. Driven secondary gear, 6. Drive main gear, 7. Intermediate gear, 8. Pump shaft, 9. Continuing device, 10. Piston rod, 11. Hollow motor shaft, 12. Inlet, 13. Outlet. Detailed Implementation

[0031] Example 1

[0032] See Figure 1 and Figure 2 A torque-changing quick coupling includes a housing 1 and a water pump shaft 8. A hollow motor shaft 11 is disposed inside the housing 1. A drive pump wheel 3 and a drive main gear 6 are mounted on the hollow motor shaft 11. A driven wheel 4 and a driven secondary gear 5 are mounted on the water pump shaft 8. An intermediate gear 7 is disposed between the drive main gear 6 and the driven secondary gear 5. A piston rod 10 is disposed inside the hollow motor shaft 11. A servo drive 9 is fixed in the annular cavity formed by the piston rod 10 and the hollow motor shaft 11. The intermediate gear 7 moves up and down under the action of the servo drive 9. The intermediate gear 7 is connected to the drive main gear 6 and the driven secondary gear 5 through gear meshing.

[0033] This embodiment is the most basic implementation method. Compared with the existing variable frequency starter and SFC starter methods, which reduce the motor speed to reduce the starting torque and reduce the motor load, this embodiment does not require reducing the motor speed. The pump shaft speed is reduced by the coupling to achieve low torque and low load start. No shutdown operation is required when switching operating conditions, which can effectively save switching time and quickly respond to the grid demand.

[0034] Example 2

[0035] See Figure 1 and Figure 2A torque-changing quick coupling includes a housing 1 and a water pump shaft 8. A hollow motor shaft 11 is disposed inside the housing 1. A drive pump wheel 3 and a drive main gear 6 are mounted on the hollow motor shaft 11. A driven wheel 4 and a driven secondary gear 5 are mounted on the water pump shaft 8. An intermediate gear 7 is disposed between the drive main gear 6 and the driven secondary gear 5. A piston rod 10 is disposed inside the hollow motor shaft 11. A servo drive 9 is fixed in the annular cavity formed by the piston rod 10 and the hollow motor shaft 11. The intermediate gear 7 moves up and down under the action of the servo drive 9. The intermediate gear 7 is connected to the drive main gear 6 and the driven secondary gear 5 through gear meshing.

[0036] The housing 1 is equipped with a movable guide vane 2 for adjusting the flow rate.

[0037] This embodiment is a preferred implementation. The housing 1 is provided with a movable guide vane 2 for adjusting the flow rate. By adjusting the opening of the movable guide vane 2, the torque transmitted from the drive pump wheel 3 to the driven impeller 4 can be controlled, thereby controlling the motor load and the starting speed of the water pump.

[0038] Example 3

[0039] See Figure 1 and Figure 2 A torque-changing quick coupling includes a housing 1 and a water pump shaft 8. A hollow motor shaft 11 is disposed inside the housing 1. A drive pump wheel 3 and a drive main gear 6 are mounted on the hollow motor shaft 11. A driven wheel 4 and a driven secondary gear 5 are mounted on the water pump shaft 8. An intermediate gear 7 is disposed between the drive main gear 6 and the driven secondary gear 5. A piston rod 10 is disposed inside the hollow motor shaft 11. A servo drive 9 is fixed in the annular cavity formed by the piston rod 10 and the hollow motor shaft 11. The intermediate gear 7 moves up and down under the action of the servo drive 9. The intermediate gear 7 is connected to the drive main gear 6 and the driven secondary gear 5 through gear meshing.

[0040] The housing 1 is equipped with a movable guide vane 2 for adjusting the flow rate.

[0041] Furthermore, the housing 1 has a water inlet 12 and a water outlet 13, with the water inlet 12 located above the water outlet 13 and the movable guide vane 2 located on one side of the water inlet 12.

[0042] This embodiment is another preferred implementation. The housing 1 has an inlet 12 and an outlet 13. The inlet 12 is located above the outlet 13, and the movable guide vane 2 is located on one side of the inlet 12. The structure is simple and facilitates the rapid start-up of the subsequent water pump.

[0043] Example 4

[0044] See Figure 1 and Figure 2 A torque-changing quick coupling includes a housing 1 and a water pump shaft 8. A hollow motor shaft 11 is disposed inside the housing 1. A drive pump wheel 3 and a drive main gear 6 are mounted on the hollow motor shaft 11. A driven wheel 4 and a driven secondary gear 5 are mounted on the water pump shaft 8. An intermediate gear 7 is disposed between the drive main gear 6 and the driven secondary gear 5. A piston rod 10 is disposed inside the hollow motor shaft 11. A servo drive 9 is fixed in the annular cavity formed by the piston rod 10 and the hollow motor shaft 11. The intermediate gear 7 moves up and down under the action of the servo drive 9. The intermediate gear 7 is connected to the drive main gear 6 and the driven secondary gear 5 through gear meshing.

[0045] The housing 1 is equipped with a movable guide vane 2 for adjusting the flow rate.

[0046] The housing 1 has an inlet 12 and an outlet 13. The inlet 12 is located above the outlet 13, and the movable guide vane 2 is located on one side of the inlet 12.

[0047] The drive pump wheel 3 is rigidly connected to the hollow motor shaft 11, and the drive pump wheel 3 is used to pressurize the incoming water flow.

[0048] This embodiment is another preferred implementation. The drive pump wheel 3 is rigidly connected to the hollow motor shaft 11. The drive pump wheel 3 is used to pressurize the incoming water flow. By driving the pump wheel 3, the water flow entering the coupling is transformed into a high-pressure water flow, which facilitates the synchronous rotation of the driven wheel 4.

[0049] Example 5

[0050] See Figure 1 and Figure 2 A torque-changing quick coupling includes a housing 1 and a water pump shaft 8. A hollow motor shaft 11 is disposed inside the housing 1. A drive pump wheel 3 and a drive main gear 6 are mounted on the hollow motor shaft 11. A driven wheel 4 and a driven secondary gear 5 are mounted on the water pump shaft 8. An intermediate gear 7 is disposed between the drive main gear 6 and the driven secondary gear 5. A piston rod 10 is disposed inside the hollow motor shaft 11. A servo drive 9 is fixed in the annular cavity formed by the piston rod 10 and the hollow motor shaft 11. The intermediate gear 7 moves up and down under the action of the servo drive 9. The intermediate gear 7 is connected to the drive main gear 6 and the driven secondary gear 5 through gear meshing.

[0051] The housing 1 is equipped with a movable guide vane 2 for adjusting the flow rate.

[0052] The housing 1 has an inlet 12 and an outlet 13. The inlet 12 is located above the outlet 13, and the movable guide vane 2 is located on one side of the inlet 12.

[0053] Furthermore, the drive pump wheel 3 is rigidly connected to the hollow motor shaft 11, and the drive pump wheel 3 is used to pressurize the incoming water flow.

[0054] Furthermore, the active guide vane 2 is used to control the magnitude of the torque transmitted asynchronously, and to lock the flow rate and the synchronous speed.

[0055] This embodiment is another preferred implementation. The movable guide vane 2 is used to control the magnitude of the torque transmitted asynchronously, and to lock the flow rate and the synchronous speed. By setting the movable guide vane 2, the starting speed of the water pump can be conveniently controlled.

[0056] Example 6

[0057] See Figure 1 and Figure 2 A torque-changing quick coupling includes a housing 1 and a water pump shaft 8. A hollow motor shaft 11 is disposed inside the housing 1. A drive pump wheel 3 and a drive main gear 6 are mounted on the hollow motor shaft 11. A driven wheel 4 and a driven secondary gear 5 are mounted on the water pump shaft 8. An intermediate gear 7 is disposed between the drive main gear 6 and the driven secondary gear 5. A piston rod 10 is disposed inside the hollow motor shaft 11. A servo drive 9 is fixed in the annular cavity formed by the piston rod 10 and the hollow motor shaft 11. The intermediate gear 7 moves up and down under the action of the servo drive 9. The intermediate gear 7 is connected to the drive main gear 6 and the driven secondary gear 5 through gear meshing.

[0058] The housing 1 is equipped with a movable guide vane 2 for adjusting the flow rate.

[0059] The housing 1 has an inlet 12 and an outlet 13. The inlet 12 is located above the outlet 13, and the movable guide vane 2 is located on one side of the inlet 12.

[0060] The drive pump wheel 3 is rigidly connected to the hollow motor shaft 11, and the drive pump wheel 3 is used to pressurize the incoming water flow.

[0061] The movable guide vane 2 is used to control the magnitude of the torque transmitted asynchronously, and to lock the flow rate and the synchronous speed.

[0062] Furthermore, the drive main gear 6 is rigidly connected to the hollow motor shaft 11, and the drive main gear 6 is used to transmit torque after synchronizing the rotation speed.

[0063] Furthermore, the driven impeller 4 is used to convert the high-pressure water flow input to the drive pump impeller 3 and output torque to the pump shaft 8, driving the pump shaft 8 from a standstill to synchronous speed.

[0064] The driven pair gear 5 is used to transmit torque through gear meshing after synchronizing the rotational speed.

[0065] The drive main gear 6 is located below the drive pump wheel 3.

[0066] The driven pair gear 5 is located below the driven rotating wheel 4.

[0067] This embodiment is the optimal implementation method, which can realize the switching between turbine and pump operation modes of the pumped storage unit through variable torque without shutting down the unit. The entire switching process is realized through mechanical and hydraulic connection, which has high structural reliability and rapid operation mode switching.

[0068] It is not only suitable for multi-condition switching of traditional low-head Francis-type two-unit pumped storage units, but also for high-head and ultra-high-head three-unit pumped storage units, making it highly adaptable.

[0069] Since it does not require frequency converter starting equipment or SFC starting equipment and is a purely mechanical operation, it can effectively reduce costs and has high reliability.

[0070] The working principle of this invention is as follows:

[0071] Before the water pump starts operating, the intermediate gear 7 is disengaged, and there is no torque transmission between the hollow motor shaft 11 and the water pump shaft 8. When the water pump starts, water is introduced into the inlet 12 of the casing 1. After passing through the drive pump impeller 3, the water becomes a high-pressure flow. This high-pressure flow drives the driven impeller 4 from rest to synchronous speed. Adjusting the opening of the movable guide vane 2 controls the flow rate into the impeller, which in turn controls the output torque of the driven impeller 4 and the acceleration of the water pump shaft 8. Lower acceleration results in a smaller motor load but a slower start-up speed, and the water pump shaft 8 takes a longer time to reach synchronous speed. Increasing the opening of the movable guide vane 2 reduces the synchronization time, allowing for faster operation transition. Once synchronous speed is reached, the opening of the movable guide vane 2 is locked, and the hollow motor shaft 11 and the water pump shaft 8 rotate synchronously without relative slippage between them. The operating relay 9 drives the intermediate gear 7 to mesh with the drive main gear 6 on the hollow motor shaft 11 and the driven secondary gear 5 on the water pump shaft 8, thus completing the rigid connection between the hollow motor shaft 11 and the water pump shaft 8. After the rigid connection is completed, the water flow into the coupling is stopped, and the water outlet 13 is opened to discharge the water in the coupling, thus completing the start-up of the water pump.

Claims

1. A torque-changing quick coupling, comprising a housing (1) and a water pump shaft (8), wherein a hollow motor shaft (11) is disposed within the housing (1), characterized in that: The hollow motor shaft (11) is equipped with a drive pump wheel (3) and a drive main gear (6). The water pump shaft (8) is equipped with a driven wheel (4) and a driven secondary gear (5). An intermediate gear (7) is provided between the drive main gear (6) and the driven secondary gear (5). A piston rod (10) is provided inside the hollow motor shaft (11). A servo device (9) is fixed in the annular cavity formed by the piston rod (10) and the hollow motor shaft (11). The intermediate gear (7) moves up and down under the action of the servo device (9). The intermediate gear (7) is connected to the drive main gear (6) and the driven secondary gear (5) respectively through gear meshing. The housing (1) is provided with a movable guide vane (2) for adjusting the flow rate. The movable guide vane (2) is used to control the magnitude of the torque transmitted asynchronously, and to lock the flow rate and the synchronous speed; The driven impeller (4) is used to convert the high-pressure water flow input to the driving pump impeller (3) and output torque to the pump shaft (8), driving the pump shaft (8) from stationary to synchronous speed.

2. The torque-changing quick coupling according to claim 1, characterized in that: The housing (1) has an inlet (12) and an outlet (13). The inlet (12) is located above the outlet (13), and the movable guide vane (2) is located on one side of the inlet (12).

3. The torque-changing quick coupling according to claim 1, characterized in that: The drive pump wheel (3) is rigidly connected to the hollow motor shaft (11), and the drive pump wheel (3) is used to pressurize the incoming water flow.

4. A torque-changing quick coupling according to claim 1, characterized in that: The drive main gear (6) is rigidly connected to the hollow motor shaft (11), and the drive main gear (6) is used to transmit torque after synchronizing the speed.

5. A torque-changing quick coupling according to claim 1, characterized in that: The driven pair gear (5) is used to transmit torque through gear meshing after synchronizing the rotational speed.

6. A torque-changing quick coupling according to claim 1, characterized in that: The drive main gear (6) is located below the drive pump wheel (3).

7. A torque-changing quick coupling according to claim 1, characterized in that: The driven pair gear (5) is located below the driven wheel (4).

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