CN114922825A

CN114922825A - Centrifugal pump structure driven by disc type motor

Info

Publication number: CN114922825A
Application number: CN202210677682.4A
Authority: CN
Inventors: 施宇钦; 杨托; 李晓琴; 刘鑫华; 张红斌
Original assignee: HANGZHOU DALU INDUSTRIAL CO LTD
Current assignee: HANGZHOU DALU INDUSTRIAL CO LTD
Priority date: 2022-06-15
Filing date: 2022-06-15
Publication date: 2022-08-19

Abstract

The invention discloses a centrifugal pump structure driven by a disc type motor. Including the pump body, pump cover and arrange rotor part, the disc motor assembly in the pump body and pump cover in, the import is seted up to pump body one end, and the pump cover closing cap is connected on the pump body other end, and rotor part, disc motor assembly all adorn in the inner chamber that forms between the pump body and pump cover, and disc motor assembly suit is on the rotor part, and it is rotatory and then produce centrifugal motion through the rotatory rotor part of disc motor assembly drive, realize the function of centrifugal pump. The invention realizes the dynamic balance of the axial force of the rotor and the self-cooling of the medium, and has the characteristics of small axial size and the whole weight, low maintainability space requirement, good vibration noise performance, self-balance of the axial force, self-cooling of the medium and the like.

Description

Centrifugal pump structure driven by disc type motor

Technical Field

The invention belongs to a centrifugal pump structure in the field of electric drive water pumps, and particularly relates to a compact water pump driven by a disc type motor.

Background

The electric drive water pump in the market basically adopts a three-phase asynchronous motor, drives an impeller through a coupler or other torque drivers, and the axial size of the electric drive water pump is generally larger.

Most of the common motor cooling forms adopt air cooling or external cooling water cooling, and for equipment with a compact and complex structure, the actual heat dissipation capacity is difficult to calculate during operation, the heat dissipation of the motor is difficult to cause in the later period, and the service efficiency and the service life of the motor are influenced.

The conventional water pump has the defects that the axial force balance of the rotor is difficult to realize due to the unbalanced pressure of the front cover plate and the rear cover plate of the impeller, and the service lives of wearing parts such as a bearing and the like are consumed at an accelerated speed.

The torque transmission path between the impeller and the shaft in the structure of the existing water pump is long, and the requirement of vibration and noise reduction of equipment is not favorably realized.

Disclosure of Invention

The invention aims to overcome the defects of the background technology and provides a disc type motor-driven centrifugal pump structure which has the advantages of compact structure, low equipment weight, small axial occupied space, self-balance axial force, good motor heat dissipation performance and the like and is mainly suitable for occasions with narrow space in cabins of ships and boats.

The invention mainly aims at improving the technology of the traditional centrifugal pump structure after the disc type motor is applied, and aims at solving the problems of motor heat dissipation, torque transmission, axial force balance and the like, and the specific scheme is described as follows:

the centrifugal pump comprises a pump body, a pump cover, a rotor component and a disc type motor assembly, wherein the rotor component and the disc type motor assembly are arranged in the pump body and the pump cover, one end of the pump body is provided with an inlet, a pump cover sealing cover is connected to the other end of the pump body, the rotor component and the disc type motor assembly are both arranged in an inner cavity formed between the pump body and the pump cover, the disc type motor assembly is sleeved on the rotor component, and the rotor component is driven to rotate by the disc type motor assembly to generate centrifugal motion, so that the function of the centrifugal pump is realized.

The rotor part comprises an impeller and a pump shaft; one end part of the pump shaft is fixedly connected with the inner end face of the pump cover through a cylindrical pin, the impeller is coaxially and rotatably sleeved on the pump shaft, the two ends of the pump shaft penetrate through the impeller and then are sleeved with round nuts, and the impeller is axially limited and mounted in a limited moving mode through the round nuts.

A disc type motor assembly is arranged between the impeller and the pump cover, the disc type motor assembly comprises an upper rotor, a stator and a lower rotor, a non-rotating annular stator is fixedly arranged between the impeller and the pump cover, the stator is sleeved outside the pump shaft and is not connected with the pump shaft and the impeller, the annular upper rotor is arranged between the stator and the pump cover, the annular lower rotor is arranged between the stator and the impeller, the stator is positioned between the upper rotor and the lower rotor, and the stator is not connected with the upper rotor and the lower rotor on the two sides respectively and has a gap; the upper rotor and the lower rotor are fixedly connected into a whole between the radial inner ring parts, and the rotor is fixedly connected with the impeller; the stator is wound with coil windings, and the end faces of the upper rotor and the lower rotor are pasted with permanent magnets.

The upper rotor and the pump cover between be equipped with self-balancing cavity structures, self-balancing cavity structures including setting up inside and outside twice annular on the pump cover inner end face protruding and set up the annular on the upper rotor terminal surface that is close to the pump cover protruding, the annular of going up the rotor is located between the inside and outside twice annular of pump cover, the annular of going up the rotor is protruding to be close to the outer annular of pump cover and is arranged but have the clearance, the clearance has between the interior annular of pump cover protruding and the upper rotor terminal surface.

The annular inflow port is formed in one end, facing the inlet of the pump body, of the impeller, the annular outflow port is formed in the outer circumferential surface of the impeller, the annular inflow port and the annular outflow port are communicated through the annular flow channel in the impeller to form an impeller flow channel in the impeller, and an annular cavity is formed in the pump body around the annular outflow port of the impeller.

The pressure relief cavity is defined by the inner annular protrusion of the pump cover and the end face of the upper rotor, the pressure regulating cavity is defined by the inner annular protrusion of the pump cover and the outer annular protrusion of the pump cover and the end face of the upper rotor, a gap between the inner annular protrusion of the pump cover and the end face of the upper rotor serves as a radial throttling ring, and a gap between the annular protrusion of the upper rotor and the outer annular protrusion of the pump cover serves as an axial throttling ring.

The inner ring parts of the impeller, the upper rotor and the lower rotor are provided with overflowing holes communicated with each other, and the pressure relief cavity is directly communicated with an impeller flow passage in the impeller through the flowing holes.

The pump cover is provided with an exhaust port at the pressure relief cavity, and the exhaust port is provided with an exhaust valve.

One end of the pump shaft extends towards the inlet of the pump body and is provided with a guide ring at the end part through an impeller nut.

The impeller is fixedly sleeved with an impeller opening ring at the periphery of the end part facing the inlet of the pump body, and an opening ring gap exists between the impeller opening ring and the inner wall of the inlet of the pump body.

The stator is fixedly connected with the wiring cover through screws, and the wiring cover is fixed between the pump body and the end face of the pump cover.

And a sealing ring is arranged between the wiring cover and the pump cover, and static sealing is realized through the sealing ring.

The upper rotor and the lower rotor of the disc type motor assembly are coaxially fixed on the impeller of the rotor part through keys, and the impeller is directly driven to rotate.

The two ends of the pump shaft are fixedly sleeved with thrust discs, a shaft sleeve and an elastic bushing are sequentially sleeved on the pump shaft between the thrust discs at the two ends, a positioning sleeve is sleeved on the pump shaft between the shaft sleeve and the elastic bushing, and the two ends of an inner hole of the impeller are respectively sleeved on the shaft sleeve and the elastic bushing through respective bearings and are rotatably and axially connected with the thrust discs at the two ends.

The shaft sleeve, the bearing and the thrust disc in the rotor part are made of wear-resistant silicon carbide materials.

The principle for realizing the dynamic balance of the axial force is as follows:

the medium lift at the outlet of the impeller is high, the medium lift at the position of the disc type motor is relatively low, and the medium enters the axial throttling ring through the gap of the motor rotor and the overflowing hole of the motor stator and then flows into the pressure regulating chamber;

at the moment, the pressure in the pressure regulating cavity is gradually increased, after the upward pressure of the front cover plate of the impeller is overcome, the whole rotor component floats downwards, the gap of the radial throttling ring is enlarged, part of the pressure is discharged, flows through the rotor overflowing hole and the impeller overflowing hole and flows back to the inlet of the impeller;

when the pressure in the pressure regulating cavity is reduced, the whole rotor component floats upwards under the pressure of the front cover plate of the impeller, and the radial throttling ring gap is reduced;

the dynamic balance of the axial force is finally achieved through repeated adjustment, and the balance principle is verified in practice.

The medium self-cooling has the following principle: in the actual operation process of the motor stator, the winding of the motor stator can generate certain heat, the motor assembly is wholly immersed in a fluid medium, and the medium flows through various overflowing holes to take away the heat.

The invention is designed and developed for solving the problem of the background art mainly, the centrifugal pump driven by the disc type motor is mainly characterized in that the disc type motor is wholly immersed in a medium and is placed in a pump body, and the structure is favorable for heat dissipation of the motor and reduces the axial size and the whole weight of equipment; the disk motor is fixed on the rear cover plate of the impeller, so that a torque transmission path is reduced, the impeller is directly driven to rotate, and the vibration noise performance of equipment is improved; and throttle gaps and overflowing holes are reasonably arranged in each part in the pump body, so that self-balance of axial force is realized.

The beneficial effects of the invention are:

the invention can well solve the traditional design problem, breaks through the traditional design thinking, and has the characteristics of small axial size and overall weight, low maintainability space requirement, good vibration noise performance, self-balancing of axial force, self-cooling of media and the like.

The disc type motor has the characteristic of small axial size, and can be applied to the condition of limited axial installation space; the heat generated by the stator winding is taken away by arranging the stator rotor overflowing hole, the impeller overflowing hole, the bearing shaft sleeve diversion trench and the like, so that the running reliability and the service life of the equipment are improved; the dynamic balance of the axial force of the rotor is realized by arranging the pump cover pressure regulating ring and the rotor pressure regulating ring; through the key-type connection, make the motor direct drive impeller rotation do work, reduce mechanical loss, improve vibration noise performance.

The invention has the advantages that:

1) the motor and the pump body of the traditional centrifugal pump unit are integrated together. The size of the whole pump unit is only the size of a common centrifugal pump head, and the size and the weight of the whole pump unit are greatly reduced.

2) The device has compact structure and low manufacturing cost.

3) In the aspect of axial force balance, the self-balance of the axial force is realized by utilizing the combination of the pressure difference of the front cavity and the rear cavity of the pump and the thrust disc.

4) Because the motor and the pump body are integrated, when the pump is maintained, the easily damaged parts in the pump body can be replaced only by detaching the bolts on the pump cover, and the maintenance operability of the whole equipment is greatly improved.

5) Compare in traditional motor drive's centrifugal pump, realized that the motor directly drives the impeller and need not the shaft coupling, this has obvious advantage to the vibration noise performance promotion of whole pump.

Drawings

Fig. 1 is a general view of a centrifugal pump structure to which a disc motor is applied.

Fig. 2 is a partial enlarged view of the pressure chamber.

Fig. 3 is an enlarged partial view of the impeller eye.

Fig. 4 is an external view of a centrifugal pump to which a disc motor is applied.

Fig. 5 is a structural view of the rotor part.

Figure 6 is an outline view of the rotor component.

Fig. 7 is a structural view of a disc motor assembly.

In the figure: the pump comprises a pump body 1, a disc type motor assembly 2, an impeller key 3, a pump cover 4, a cylindrical pin 5, a rotor component 6, an exhaust valve 7, a round nut 8, a sealing gasket 9, a nut 10, a bolt 11, a power supply connector 12, an impeller nut 13, a mouth ring gap 14, a pressure relief cavity 15, a radial throttling ring 16, a pressure regulating cavity 17, an axial throttling ring 18, a fixing screw 21, an upper motor rotor 22, a motor stator 23, a lower motor rotor 24 and a wiring cover 25; impeller collar 61, impeller 62, bearing 63, shaft sleeve 64, elastic bushing 65, thrust disc 66, pump shaft 67, locating sleeve 68 and round nut 69.

Detailed Description

How the present invention may be carried into effect will now be further described with reference to the accompanying drawings.

As shown in fig. 1, centrifugal pump structure is vertical to be arranged, including the pump body 1, pump cover 4 and place the rotor part 6 in the pump body 1 and pump cover 4, disc motor assembly 2, the import is seted up to 1 one end of the pump body, pump cover 4 closing cap is connected on 1 other end of the pump body, rotor part 6, disc motor assembly 2 is all adorned in the inner chamber that forms between the pump body 1 and pump cover 4, disc motor assembly 2 suit is on rotor part 6, it is rotatory and then produce centrifugal motion to drive rotor part 6 through disc motor assembly 2, realize the function of centrifugal pump.

As shown in fig. 5, rotor component 6 includes an impeller 62 and a pump shaft 67; the pump shaft 67 is axially arranged along an inlet of the pump body 1, one end part of the pump shaft 67 is fixedly connected with the inner end face of the pump cover 4 through the cylindrical pin 5, the impeller 62 is coaxially and rotatably sleeved on the pump shaft 67 through the bearing 63, the shaft sleeve 64, the elastic bushing 65, the thrust disc 66 and the positioning sleeve 68, the two ends of the pump shaft 67 penetrate through the impeller 62 and then are sleeved with the round nuts, in fig. 1, the upper end penetrates through the rear sleeve and then is sleeved with the round nut 8, the lower end penetrates through the rear sleeve and then is sleeved with the round nut 69, and the impeller 62 is axially limited and mounted in a limited movement mode through the round nuts.

In a specific implementation, the impeller 62 extends axially from an annular sleeve portion at an end facing the pump cover 4, and the annular sleeve portion is coaxially and rotatably sleeved on the pump shaft 67 through a bearing 63, a shaft sleeve 64, an elastic bushing 65, a thrust disc 66 and a positioning sleeve 68. The periphery of the annular sleeve part of the impeller 62 is provided with a key groove which is used for mounting the disc type motor assembly 2, a key is mounted in the key groove, and the upper rotor 22 and the lower rotor 24 are coaxially sleeved on the annular sleeve part through the key 3.

The impeller 62 is provided with an annular inflow port at one end facing the inlet of the pump body 1, an annular outflow port is provided at the outer circumferential surface, the annular inflow port and the annular outflow port are communicated through an annular flow passage inside the impeller 62 to form an impeller flow passage inside the impeller 62, and an annular chamber is arranged in the pump body 1 around the annular outflow port of the impeller 62. An outlet is arranged on one side wall of the pump body 1 around the annular cavity.

As shown in fig. 5 and 6, thrust disks 66 are fixedly sleeved at both ends of a pump shaft 67, the thrust disks 66 at both ends are respectively axially positioned and connected with round nuts at both ends of the pump shaft 67, a shaft sleeve 64 and an elastic bushing 65 are sequentially sleeved on the pump shaft 67 between the thrust disks 66 at both ends, a positioning sleeve 68 is sleeved on the pump shaft 67 between the shaft sleeve 64 and the elastic bushing 65, the shaft sleeve 64, the elastic bushing 65 and the positioning sleeve 68 are all fixed and do not rotate like the pump shaft 67, both ends of an inner hole of an impeller 62 are respectively sleeved on the shaft sleeve 64 and the elastic bushing 65 through respective bearings 63 and are rotatably and axially connected with the thrust disks 66 at both ends, and axial supporting rotation and radial supporting rotation are simultaneously realized through the bearings 63. And the impeller 62 is axially and slightly movably mounted between the thrust disks 66 at both ends through bearings 63 at both ends.

The two bearings 63 are assembled in the inner hole of the impeller in an interference manner, and a thrust disc 66, an elastic bush 65, a shaft sleeve 64 and a positioning sleeve 68 are sequentially arranged on the pump shaft; the pump shaft 67 is inserted into the remaining thrust disk 66 after penetrating the inner hole of the impeller bearing, and is fastened by a round nut 69. The shaft sleeves 64 and the bearings 63 at the two ends of the rotor part 6 are placed between the thrust discs 66 at the two ends, so that the axial displacement of the rotor is limited.

One end of the pump shaft 67 extends towards the inlet of the pump body 1, and a guide ring is arranged at the end part through the impeller nut 13 and used for limiting the axial movement of the pump. A guide ring is arranged at the inlet of the pump body 1, and the guide ring is matched with the pump shaft 67 and then fixed by an impeller nut 13.

As shown in fig. 3, an impeller mouth ring 61 is fixedly sleeved on the periphery of the end part of the impeller 62 facing the inlet of the pump body 1, the impeller mouth ring 61 is fixed on the impeller 62 in a spot welding manner, the impeller mouth ring 61 is a replaceable part which can be made without replacing a new impeller or pump body due to the enlargement of a mouth ring gap 14 caused by the long-time operation of equipment and further causes the deviation of the flow rate and the lift, the mouth ring gap 14 is formed between the impeller mouth ring 61 and the inner wall of the inlet of the pump body 1, the mouth ring gap 14 is used for assisting in adjusting the balance of the axial force of the rotor, and simultaneously, the relatively disordered flowing state of the fluid at the inlet of the impeller is ensured.

In specific implementation, the impeller collar 61 and the pump body 1 are matched to form a collar gap 14 of about 0.25 mm.

The friction surface materials of the bearing 63, the shaft sleeve 64 and the thrust disc 66 are all made of silicon carbide, the inner wall of the bearing is provided with a flow guide groove, the friction resistance in the operation process is reduced in a water lubrication mode, and the friction surface materials are also used as a medium flowing channel, so that the heat productivity generated in the operation process of the motor can be taken away.

The elastic bushing 65 is provided with a wire cutting groove to compensate the deformation of the elastic bushing 65 due to thermal expansion of the material, compensate the difference of the thermal expansion amount of the material of the elastic bushing under various temperature working conditions, and avoid the friction generated by the thermal expansion.

As shown in fig. 7, a disc motor assembly 2 is arranged between the impeller 62 and the pump cover 4, the disc motor assembly 2 includes an upper rotor 22, a stator 23 and a lower rotor 24, a non-rotating annular stator 23 is fixedly arranged between the impeller 62 and the pump cover 4, the stator 23 is sleeved outside the pump shaft 67 and is not connected with the pump shaft 67 and the impeller 62, an annular upper rotor 22 is arranged between the stator 23 and the pump cover 4, an annular lower rotor 24 is arranged between the stator 23 and the impeller 62, the stator 23 is located between the upper rotor 22 and the lower rotor 24, and the stator 23 is not connected with the upper rotor 22 and the lower rotor 24 on both sides and has a gap;

the inner ring parts of the upper rotor 22 and the lower rotor 24 extend inwards in the radial direction and cross the inner ring part of the stator 23, the upper rotor 22 and the lower rotor 24 are fixedly connected into a whole rotor between the radial inner ring parts through rivets, and the rotor is fixedly connected with the impeller 62;

the disk type motor assembly 2 is integrally in a disk shape, a coil winding is wound on the stator 23, and permanent magnets are attached to the end faces of the upper rotor 22 and the lower rotor 24. The coil winding on the stator 23 is electrified to control and generate a magnetic field, so that the permanent magnets on the upper rotor 22 and the lower rotor 24 are driven to rotate, and the upper rotor 22 and the lower rotor 24 are further driven to rotate.

In specific implementation, a plurality of pairs of magnetic poles are arranged on the upper rotor and the lower rotor in the circumferential direction, the adjacent permanent magnet magnetic poles are the same, and the corresponding permanent magnet magnetic poles of the upper rotor and the lower rotor are opposite; the coil windings are all packaged in the motor stator 23, and the packaging materials are all insulating materials such as epoxy resin and the like; the direction of the electromagnetic force borne by the coil is not changed due to the alternating magnetic field generated by electromagnetic induction, and the continuous operation of the motor is ensured.

The upper rotor 22/24 and the lower rotor 22/24 are axially and uniformly distributed with a plurality of magnetic steel sheets, and the upper magnetic pole and the lower magnetic pole are mutually corresponding.

As shown in fig. 1 and 4, the stator 23 is fixedly connected to an annular terminal cover 25 by screws 21, the terminal cover 25 is fixed between the end faces of the pump body 1 and the pump cover 4, and the terminal cover 25 is fixedly connected between the pump body 1 and the pump cover 4 by a gasket 9, bolts 11, and nuts 10, thereby fixedly mounting the stator 23. And a sealing ring 9 is arranged between the wiring cover 25 and the pump cover 4, and static sealing is realized through the sealing ring 9.

The wiring cover 25 is internally provided with a threading hole, the power connector 12 is externally connected through the threading hole, and the power connector 12 is electrically connected with the coil winding on the stator 23.

The upper rotor 22 and the lower rotor 24 of the disc type motor assembly 2 are coaxially fixed on the impeller 62 of the rotor part 6 through the key 3, and directly drive the impeller to rotate 62.

Go up rotor 22 and pump cover 4 between be equipped with self-balancing cavity structure, self-balancing cavity structure is protruding and set up the annular on the 22 terminal surfaces of last rotor that is close to pump cover 4 including setting up the inside and outside twice annular on the terminal surface in pump cover 4, the annular of last rotor 22 is protruding to be located between the inside and outside twice annular of pump cover 4, the annular of going up rotor 22 is protruding to be close to more to the outer annular of pump cover 4 and is protruding to be arranged but has the clearance, the interior annular of pump cover 4 is protruding to have the clearance with between the 22 terminal surfaces of last rotor.

As shown in fig. 2, the inner annular protrusion of the pump cover 4 and the end surface of the upper rotor 22 enclose a pressure relief cavity 15, a pressure regulating cavity 17 is enclosed between the inner and outer annular protrusions of the pump cover 4 and the end surface of the upper rotor 22, a gap between the inner annular protrusion of the pump cover 4 and the end surface of the upper rotor 22 serves as a radial restrictor ring 16, and a gap between the annular protrusion of the upper rotor 22 and the outer annular protrusion of the pump cover 4 serves as an axial restrictor ring 18, so as to achieve dynamic balance of axial force of the rotor component 6.

The pump cover 4 is provided with an air outlet at the pressure relief cavity 15, an air outlet valve 7 is installed at the air outlet, and the air outlet valve 7 is used for exhausting air before the pump is started.

In a specific implementation, the radial throttle ring 16 and the axial throttle ring 18 both have a throttle gap of about 0.25 mm.

Both ends of the pressure regulating cavity 17 can be communicated with the cavities at both sides only through the radial throttling ring 16 and the axial throttling ring 18, so that the pressure regulating cavity 17 is a relatively closed cavity, and further the axial direction of the impeller 62 is balanced.

The inner ring parts of the impeller 62, the upper rotor 22 and the lower rotor 24 are provided with overflowing holes communicated with each other and used for transferring heat of circulating media, the overflowing holes are small through holes, the pressure relief cavity 15 is directly communicated with an impeller flow channel in the impeller 62 through the flowing holes, circulating pressure relief and cooling are simultaneously realized through the overflowing holes, and the fluid media of the circulating media flow through the overflowing holes to take away heat of the motor.

The side of the motor stator 23 is drilled with an overflowing hole, the overflowing holes of the upper and lower rotors of the motor and the overflowing holes of the impeller interact with the pressure regulating chamber to form a complete water flow pressure passage, so that the dynamic balance of axial force and the self-cooling of media are realized.

The axial throttling ring, the radial throttling ring and the overflowing holes act together to regulate the pressure of the pressure regulating cavity and the pressure relief cavity, and the pressure difference between the front cover plate and the rear cover plate of the impeller 62 is regulated through the dynamic change of the medium flow velocity in the gap between the two throttling gaps, so that the dynamic balance of the axial force is realized.

The fluid medium entering from the inlet of the pump body 1 enters the impeller flow channel inside the impeller 62, the fluid medium flows into the annular cavity of the pump body 1 from the impeller flow channel inside the impeller 62, one part of the fluid medium flows out from the outlet of the pump body 1 after flowing through the annular cavity, the other part of the fluid medium flows into the annular gap between the stator 23 and the lower rotor 24 from the annular cavity, then flows into the inner ring transition cavity formed between the inner ring part of the stator 23 and the upper rotor 22 and the lower rotor 24 respectively, then flows into the annular gap between the stator 23 and the upper rotor 22 from the inner ring transition cavity, then flows into the rear cavity between the outer annular bulge periphery of the pump cover 4 and the end surface of the upper rotor 22 from the annular gap between the stator 23 and the upper rotor 22, then flows into the pressure regulating cavity 17 from the rear cavity through the axial throttling ring 18, and then flows into the pressure relief cavity 15 from the pressure regulating cavity 17 through the radial throttling ring 16, then flows back to the impeller flow channel from the pressure relief cavity 15 through the flow hole for circulation, and can flow out of the pump body to take away heat generated by the operation of the centrifugal pump structure.

When impeller 62 and the whole axial displacement of rotor are close to pump cover 4, drive radial restrictor ring 16, the clearance of axial restrictor ring 18 diminishes, the inflow and the outflow of pressure regulating chamber 17 all become less, make pressure regulating chamber 17 become relative confined cavity, pressure regulating chamber 17 is whole by impeller 62 and rotor extrusion this moment, make the pressure increase of pressure regulating chamber 17, pressure regulating chamber 17 can feed back fluid medium effort and then drive impeller 62 axial and reply balanced position to the rotor, the axial displacement of pump cover 4 is kept away from to the orientation.

When the impeller 62 and the rotor move axially towards the direction away from the pump cover 4, the gap between the radial throttling ring 16 and the axial throttling ring 18 is driven to be enlarged, the inflow and the outflow of the pressure regulating cavity 17 are both enlarged, so that the pressure regulating cavity 17 is not relatively closed any more, the fluidity of the pressure regulating cavity 17 is enhanced, the pressure of the pressure regulating cavity 17 is reduced, and the impeller 62 can be impacted by a fluid medium at the inlet of the pump body to move axially towards the pump cover 4.

According to the invention, through the arrangement of the relationship among the disc type motor assembly 2, the impeller 62 and the pump cover 4, the rotor of the disc type motor assembly 2 can be in axial self-adaptive floating motion skillfully, the pressure on two sides and around can be adjusted, and the effect and advantage of dynamic self-balancing of axial force can be realized.

When the water pressure in the centrifugal pump structure rises, the temperature can rise, the pressure relief cavity 15 flows back to the impeller flow channel through the flow hole to circulate, the heat can be driven by flowing, and meanwhile, a good medium self-cooling effect is achieved.

Claims

1. A centrifugal pump structure driven by a disc type motor is characterized in that: including the pump body (1), pump cover (4) and arrange rotor part (6) in the pump body (1) and pump cover (4) in, disc motor assembly (2), the import is seted up to pump body (1) one end, pump cover (4) closing cap is connected on pump body (1) other end, rotor part (6), disc motor assembly (2) all adorn in the inner chamber that forms between the pump body (1) and pump cover (4), disc motor assembly (2) suit is on rotor part (6), it is rotatory and produce centrifugal motion to drive rotor part (6) through disc motor assembly (2), realize the function of centrifugal pump.

2. A disc motor driven centrifugal pump structure according to claim 1, wherein:

the rotor part (6) comprises an impeller (62) and a pump shaft (67); one end part of the pump shaft (67) is fixedly connected with the inner end face of the pump cover (4) through a cylindrical pin (5), the impeller (62) is coaxially and rotatably sleeved on the pump shaft (67), the two ends of the pump shaft (67) penetrate through the impeller (62) and are sleeved with round nuts, and the impeller (62) is axially limited and movably mounted in a limiting manner through the round nuts;

a disc type motor assembly (2) is arranged between the impeller (62) and the pump cover (4), the disc type motor assembly (2) comprises an upper rotor (22), a stator (23) and a lower rotor (24), a non-rotating annular stator (23) is fixedly arranged between the impeller (62) and the pump cover (4), the stator (23) is sleeved outside the pump shaft (67) and is not connected with the pump shaft (67) and the impeller (62), the annular upper rotor (22) is arranged between the stator (23) and the pump cover (4), the annular lower rotor (24) is arranged between the stator (23) and the impeller (62), the stator (23) is positioned between the upper rotor (22) and the lower rotor (24), and the stator (23) is not connected with the upper rotor (22) and the lower rotor (24) on two sides respectively and has a gap; the upper rotor (22) and the lower rotor (24) are fixedly connected into a whole between the radial inner ring parts, and the rotor is fixedly connected with the impeller (62); the stator (23) is wound with coil windings, and the end faces of the upper rotor (22) and the lower rotor (24) are pasted with permanent magnets.

3. A disc motor driven centrifugal pump structure according to claim 2, wherein:

go up rotor (22) and pump cover (4) between be equipped with self-balancing cavity structure, self-balancing cavity structure is including setting up inside and outside twice annular protrusion on pump cover (4) inner end face and setting up the annular protrusion on last rotor (22) terminal surface near pump cover (4), the annular protrusion of going up rotor (22) is located between the inside and outside twice annular protrusion of pump cover (4), the annular protrusion of going up rotor (22) is close to the outer annular protrusion of pump cover (4) and arranges but has the clearance, the interior annular protrusion of pump cover (4) and last rotor (22) terminal surface between have the clearance.

4. A disc motor driven centrifugal pump structure according to claim 2, wherein:

the pump body (1) around the annular outflow port of impeller (62) is equipped with the annular inflow port in the one end towards pump body (1) import, offers annular outflow port at the peripherad, forms the impeller runner of impeller (62) inside through the inside annular runner intercommunication of impeller (62) between annular inflow port and the annular outflow port, is equipped with the annular chamber in the pump body (1) around the annular outflow port of impeller (62).

5. A disc motor driven centrifugal pump structure according to claim 2, wherein:

the pressure relief structure is characterized in that a pressure relief cavity (15) is formed by the inner annular protrusion of the pump cover (4) and the end face of the upper rotor (22) in a surrounding mode, a pressure regulating cavity (17) is formed by the inner annular protrusion of the pump cover (4) and the outer annular protrusion of the upper rotor (22) in a surrounding mode, a gap between the inner annular protrusion of the pump cover (4) and the end face of the upper rotor (22) serves as a radial throttling ring (16), and a gap between the annular protrusion of the upper rotor (22) and the outer annular protrusion of the pump cover (4) serves as an axial throttling ring (18).

6. A disc motor driven centrifugal pump structure according to claim 1, wherein:

the inner ring parts of the impeller (62), the upper rotor (22) and the lower rotor (24) are provided with overflowing holes communicated with each other, and the pressure relief cavity (15) is directly communicated with an impeller flow passage in the impeller (62) through the overflowing holes.

7. A disc motor driven centrifugal pump structure according to claim 1, wherein:

the pump cover (4) is provided with an exhaust port at the pressure relief cavity (15), and the exhaust port is provided with an exhaust valve (7).

8. A disc motor driven centrifugal pump structure according to claim 1, wherein:

the impeller (62) is fixedly sleeved with an impeller opening ring (61) at the periphery of the end part facing the inlet of the pump body (1), and an opening ring gap (14) exists between the impeller opening ring (61) and the inner wall of the inlet of the pump body (1).

9. A disc motor driven centrifugal pump structure according to claim 1, wherein:

both ends of pump shaft (67) all fixed cover be equipped with thrust disc (66), the cover is equipped with axle sleeve (64) and elastic bushing (65) in proper order on pump shaft (67) between thrust disc (66) at both ends, suit position sleeve (68) are gone up in pump shaft (67) between axle sleeve (64) and elastic bushing (65), the both ends of impeller (62) hole all through respective bearing (63) suit respectively at axle sleeve (64), elastic bushing (65) go up and rotatably the axial connection with thrust disc (66) at both ends.

10. A disc motor driven centrifugal pump structure according to claim 1 or 9, wherein: the shaft sleeve (64), the bearing (63) and the thrust disc (66) in the rotor part (6) are made of wear-resistant silicon carbide materials.