Internal circulation adjusting mechanism of shield pump and shield pump

Abstract

The utility model relates to a shield pump internal circulation adjusting structure and a shield pump, and the shield pump internal circulation adjusting mechanism comprises a telescopic assembly which is arranged at the first end of an axial through hole formed in the center of a rotating shaft of an impeller, and the first end of the axial through hole is the end away from an inlet of the shield pump; and the control assembly is connected with the telescopic assembly and is arranged to control the telescopic assembly to stretch out and draw back so as to adjust the distance between the first end of the axial through hole and the telescopic assembly. According to the technical scheme, the internal circulation amount of the shield pump is reduced under the small-flow working condition, and therefore the efficiency of the water pump is improved; meanwhile, the internal circulation amount is kept under the large-flow working condition, motor heat dissipation is accelerated, and the service life of the motor is prolonged.

Description

Technical Field

[0001] The utility model relates to the technical field of shielded pumps, in particular to an internal circulation regulating mechanism of a shielded pump and a shielded pump. Background Art

[0002] As a fluid machine for energy transmission, water pumps convert the mechanical energy of the motor into the energy of the fluid during their operation, thereby transporting the fluid to a high place to increase potential energy or a higher pressure space. They are widely used in various industries today. As a type of water pump, the canned pump is a centrifugal sealless pump. The pump and the drive motor are enclosed in a pressure vessel filled with the pumping medium. This pressure vessel has only static seals. The canned pump eliminates the rotating shaft sealing device of the traditional centrifugal pump and can be completely leak-free. The canned pump can be lubricated and dissipated by its conveying medium, so no additional lubricating grease and cooling fan are required.

[0003] Existing shielded pump products usually have through holes on the impeller shaft and bearings to achieve lubrication of the impeller bearings by the conveying medium. At the same time, the heat on the motor stator and rotor is taken away by the medium to achieve a heat dissipation process, which is usually called internal circulation.

[0004] However, when the existing shielded pump includes an internal circulation mode, the medium inside the shielding sleeve will cause the shielded pump efficiency to decrease, which is generally about 8% lower than that of an ordinary centrifugal pump. Since the diameter of the through hole on the impeller shaft cannot usually be changed, the following phenomena will occur: when the water pump is working in the rated working area, the internal circulation volume is relatively balanced with the heat dissipation required by the motor, the water pump efficiency is relatively stable, and the motor temperature is relatively stable; when the water pump is working in a small flow area, the internal pressure difference of the water pump is large, resulting in an increase in the internal circulation volume, while the motor load is low under this condition, and no excessive medium is required for heat dissipation. The increased internal circulation volume will cause the water pump efficiency to decrease; when the water pump is working in a large flow area, the internal pressure difference of the water pump is small, resulting in a decrease in the internal circulation volume, while the motor load is high under this condition, and more medium is required for heat dissipation. The small internal circulation volume will cause the water pump motor temperature to increase and reduce the motor life. Utility Model Content

[0005] The utility model aims to provide a canned pump internal circulation regulating mechanism and a canned pump, so as to regulate the internal circulation of the canned pump.

[0006] In order to achieve the above-mentioned purpose, the utility model provides a canned pump internal circulation regulating mechanism, comprising:

[0007] The telescopic assembly is arranged at the first end of the axial through hole opened at the center of the impeller shaft, wherein the first end of the axial through hole is the end away from the inlet of the shielded pump;

[0008] The control component is connected to the telescopic component and is configured to control the telescopic movement of the telescopic component to adjust the distance between the first end of the axial through hole and the telescopic component.

[0009] Optionally, the telescopic component is an electric push rod, and the electric push rod and the axial through hole are coaxially arranged.

[0010] Optionally, the head of the electric push rod is in the shape of a sphere, a semi-sphere or a cone.

[0011] Optionally, the diameter of the rod head is greater than or equal to the diameter of the first end of the axial through hole.

[0012] Optionally, the first end of the axial through hole is provided with a chamfer.

[0013] The utility model embodiment also provides a shielded pump, characterized in that it includes the shielded pump internal circulation adjustment mechanism provided by any embodiment, and also includes an impeller shaft, the center of which is provided with an axial through hole, which is inserted into the shielding sleeve; the end of the shielding sleeve close to the inlet of the shielded pump is connected to a cover plate, and the bottom of the shielding sleeve is installed with a bottom bearing; a cover plate through hole is provided on the cover plate; the bottom bearing is sleeved with the end of the impeller shaft away from the inlet of the shielded pump, and an opening is provided on the bottom bearing; the impeller is sleeved with the end of the impeller shaft close to the inlet of the shielded pump.

[0014] Optionally, the shielded pump further includes a motor rotor, which is sleeved on the middle section of the impeller shaft and is arranged in the shielding sleeve.

[0015] Optionally, the shielded pump further includes a top bearing, which is sleeved on the impeller shaft and is relative to the motor rotor and close to the shielded pump inlet.

[0016] Optionally, the shielded pump further includes a pump body, a shielding sleeve is installed in the pump body, and a motor stator core is installed between the pump body and the shielding sleeve.

[0017] Optionally, the shielded pump also includes a telescopic component mounting position for fixing the telescopic component.

[0018] As can be seen from the above, the technical solution provided by the embodiment of the utility model, the shielded pump internal circulation regulating mechanism, can reduce the shielded pump internal circulation volume under low flow conditions through the telescopic component, thereby improving the pump efficiency; at the same time, the internal circulation volume is maintained under high flow conditions, accelerating the heat dissipation of the motor and improving the life of the motor. The telescopic component is controlled by the control component to achieve self-regulation of the shielded pump internal circulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the cross-sectional structure of the shielding screen provided by the embodiment of the utility model;

[0020] Figure 2 It is a structural schematic diagram of a telescopic assembly provided in an embodiment of the utility model;

[0021] Figure 3 It is a schematic diagram of the internal circulation of the canned pump under a small flow rate provided by an embodiment of the utility model;

[0022] Figure 4 It is a schematic diagram of the internal circulation of a shielded pump under a large flow rate provided by an embodiment of the utility model. DETAILED DESCRIPTION

[0023] The technical solution of the utility model is further described below in conjunction with the accompanying drawings and through specific implementation methods. It is understood that the specific embodiments described herein are only used to explain the utility model, rather than to limit the utility model. It is also necessary to explain that, for the convenience of description, only the parts related to the utility model are shown in the accompanying drawings, rather than all.

[0024] Some directional words are defined in the present utility model. Unless otherwise specified, the directional words used, such as "upper", "lower", "left", "right", "inside" and "outside", are used for ease of understanding and therefore do not constitute limitations on the protection scope of the present utility model.

[0025] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0026] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0027] The utility model embodiment provides a canned pump internal circulation regulating mechanism, such as Figure 1 As shown, including:

[0028] The telescopic assembly 005 is arranged at the first end of the axial through hole opened at the center of the impeller shaft 007, wherein the first end of the axial through hole is the end away from the inlet 100 of the canned pump;

[0029] The control component 006 is connected to the telescopic component 005 and is configured to control the telescopic movement of the telescopic component 005 so as to adjust the distance between the first end of the axial through hole and the telescopic component 005 .

[0030] The closer the telescopic component 005 is to the first end of the axial through hole under the control of the control component 006, the smaller the internal circulation amount is; conversely, the farther the telescopic component 005 is from the first end of the axial through hole under the control of the control component 006, the larger the internal circulation amount is. In this way, self-regulation of the internal circulation can be achieved. The control component 006 can supply power to the telescopic component 005 and send a control signal to it. Figure 1 The specific connection lines between the two are omitted.

[0031] Optional, such as Figure 2 As shown, the telescopic component 005 can be an electric push rod, and the electric push rod and the axial through hole are coaxially arranged.

[0032] Optionally, the head of the electric push rod is in the shape of a sphere, a semi-sphere or a cone. Figure 2 The semi-circular ball is taken as an example. The rod head of the electric push rod is set in a protruding shape. When adjusting the internal circulation, the front end of the rod head can extend into the axial through hole, which can better control the internal circulation volume under the condition of small flow of the shielded pump.

[0033] Optionally, the diameter of the rod head is greater than or equal to the diameter of the first end of the axial through hole.

[0034] Optionally, the first end of the axial through hole is provided with a chamfer, wherein the chamfer of the axial through hole is suitable for matching the protruding shape of the rod head, which is beneficial for accurately controlling the internal circulation amount.

[0035] An embodiment of the utility model also provides a shielded pump, including the shielded pump internal circulation regulating mechanism provided by any of the above embodiments, and also including an impeller shaft 007, an axial through hole is opened at the center of which is passed through the shielding sleeve 008; the end of the shielding sleeve 008 close to the shielding pump inlet 100 is connected with a cover plate 002, and the bottom of the shielding sleeve 008 is installed with a bottom bearing 004; a cover plate through hole is opened on the cover plate 002; the bottom bearing 008 is sleeved on the end of the impeller shaft 007 away from the shielding pump inlet 100, and an opening is provided on the bottom bearing 004; an impeller 009, which is sleeved on the end of the impeller shaft 007 close to the shielding pump inlet 100.

[0036] Optionally, the shielded pump further includes a motor rotor 011 , which is sleeved on the middle section of the impeller shaft 007 and disposed in the shielding sleeve 008 .

[0037] Optionally, the shielded pump further includes a top bearing 012 , which is sleeved on the impeller shaft 007 and is close to the shielded pump inlet 100 relative to the motor rotor 011 .

[0038] Optionally, the shielded pump further includes a pump body 001 , a shielding sleeve 008 is installed in the pump body 001 , and a motor stator core 003 is installed between the pump body 001 and the shielding sleeve 008 .

[0039] Optionally, the shielded pump also includes a telescopic component mounting position 010 for fixing the telescopic component 005.

[0040] When the shielded pump is working, due to the high-speed rotation of the impeller 009 to form a low-pressure area, the medium inside the pump body 001 will enter the shielding sleeve 008 through the cover plate 002 under the action of the pressure difference; continue to enter the bottom space of the impeller shaft 007 through the opening on the bottom bearing 004; enter the opening of the axial through hole at the bottom of the impeller shaft 007 through the small gap formed by the telescopic component 005 and the impeller shaft 007; and be transmitted to the top opening through the bottom opening of the impeller shaft 007 to complete the internal circulation. Figure 1 , 3 As shown in Figures 4 and 5, the direction of the arrow is the direction of medium flow.

[0041] like Figure 3 As shown, under low flow, the control component 006 controls the telescopic component 005 to extend forward to reduce the internal circulation amount; Figure 4 When the flow rate is large, the control component 006 controls the telescopic component 005 to shrink backward to increase the internal circulation volume. It can be understood that small flow rate and large flow rate are equivalent, and are divided according to the working capacity of the shielded pump. Different models of shielded pumps have different specific flow values ​​under different flow conditions.

[0042] As can be seen from the above, the technical solution provided by the embodiment of the utility model, the shielded pump internal circulation regulating mechanism, can reduce the shielded pump internal circulation volume under low flow conditions through the telescopic component, thereby improving the pump efficiency; at the same time, the internal circulation volume is maintained under high flow conditions, accelerating the heat dissipation of the motor and improving the life of the motor. The telescopic component is controlled by the control component to achieve self-regulation of the shielded pump internal circulation.

[0043] Although the utility model has been described in detail above by means of general description, specific implementation methods and tests, it is obvious to those skilled in the art that some modifications or improvements can be made to the utility model. Therefore, these modifications or improvements made without departing from the spirit of the utility model are within the scope of protection claimed by the utility model.

Claims

1. A canned motor pump internal circulation regulating mechanism, characterized in that: include: The telescopic assembly is arranged at the first end of the axial through hole opened at the center of the impeller shaft, wherein the first end of the axial through hole is the end away from the inlet of the shielded pump; A control component is connected to the telescopic component and is configured to control the telescopic movement of the telescopic component to adjust the distance between the first end of the axial through hole and the telescopic component.

2. The canned motor pump internal circulation regulating mechanism according to claim 1 is characterized in that: The telescopic component is an electric push rod, and the electric push rod and the axial through hole are coaxially arranged.

3. The canned motor pump internal circulation regulating mechanism according to claim 2 is characterized in that: The rod head of the electric push rod is in the shape of a sphere, a semi-sphere or a cone.

4. The canned motor pump internal circulation regulating mechanism according to claim 3 is characterized in that: The diameter of the rod head is greater than or equal to the diameter of the first end of the axial through hole.

5. The canned motor pump internal circulation regulating mechanism according to any one of claims 1 to 4, characterized in that: The first end of the axial through hole is provided with a chamfer.

6. A canned motor pump, characterized in that: It comprises the internal circulation regulating mechanism of the shielded pump as described in any one of claims 1 to 5, and also comprises an impeller shaft, a center of which is provided with an axial through hole, which is passed through the shielding sleeve; a cover plate is connected to the end of the shielding sleeve close to the inlet of the shielded pump, and a bottom bearing is installed at the bottom of the shielding sleeve; a cover plate through hole is provided on the cover plate; the bottom bearing is sleeved on the end of the impeller shaft away from the inlet of the shielded pump, and an opening is provided on the bottom bearing; an impeller, which is sleeved on the end of the impeller shaft close to the inlet of the shielded pump.

7. The canned motor pump according to claim 6, characterized in that: It also includes a motor rotor, which is sleeved on the middle section of the impeller shaft and is arranged in the shielding sleeve.

8. The canned motor pump according to claim 7, characterized in that: It also includes a top bearing, which is sleeved on the impeller shaft and is close to the shielded pump inlet relative to the motor rotor.

9. The canned motor pump according to claim 6, characterized in that: It also includes a pump body, in which the shielding sleeve is installed, and a motor stator core is installed between the pump body and the shielding sleeve.

10. The canned motor pump according to any one of claims 6 to 9, characterized in that: It also includes a telescopic component mounting position for fixing the telescopic component.

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