CN114294240A

CN114294240A - Working method of drainage type constant-pressure self-priming pump with external open type pressure relief valve body

Info

Publication number: CN114294240A
Application number: CN202111671419.6A
Authority: CN
Inventors: 黄晓军
Original assignee: Jiangsu Jinrongsen Refrigeration Technology Co Ltd
Current assignee: Jiangsu Jinrongsen Refrigeration Technology Co Ltd
Priority date: 2021-12-31
Filing date: 2021-12-31
Publication date: 2022-04-08
Anticipated expiration: 2041-12-31
Also published as: CN114294240B

Abstract

The invention relates to a working method of a drainage type constant-pressure self-priming pump with an externally-opened pressure relief valve body, wherein the drainage pump rotates together due to the rotation of a motor rotating shaft, and when an impeller rotates at high speed, the air in a suction cavity is exhausted infinitely after cycles because the suction cavity of a pump body and a pump inlet are the same in atmospheric pressure; the liquid in the external storage tank is sucked into the suction cavity through the drainage pump, and then the liquid with higher pressure is obtained by the rotating impeller under the action of high-speed inertial centrifugal force, enters the discharge pipeline from the pump outlet and is conveyed to a required place. The invention can be suitable for conveying low-temperature and high-viscosity liquid and high-temperature and low-viscosity liquid, and the motor can stably operate and has stable output pressure.

Description

Working method of drainage type constant-pressure self-priming pump with external open type pressure relief valve body

Technical Field

The invention relates to a working method of a drainage type constant-pressure self-priming pump with an outward opening type pressure relief valve body.

Background

A pump: is a machine for transporting liquids.

The pump is divided into according to its theory of operation: dynamic pumps (vane), positive displacement pumps (positive displacement), other types of pumps. A dynamic pump (impeller type) is a pump that uses an impeller rotating at a high speed to transfer liquid by applying work to the liquid by a blade, such as a centrifugal pump, a vortex pump, a mixed flow pump, and an axial flow pump. According to the impeller suction mode: single and multiple suction pumps; dividing according to the number of impellers: single stage pumps and multi-stage pumps; dividing according to the position of a pump shaft: horizontal pumps and vertical pumps, etc.; according to the installation height and the working mode of the pump: self-priming centrifugal pumps and suction centrifugal pumps.

The centrifugal pump is characterized in that: 1. the structure is simple, the operation is easy, and the adjustment and the control are convenient; 2, the flow is uniform, and the benefit is high; 3. the application range of flow and pressure is wide; 4. the conveying device is suitable for conveying corrosive or suspended liquid, and has the advantages of low running noise, low manufacturing cost, durability, excellent stability and the like.

The self-priming centrifugal pump has certain self-priming capacity, makes up the defect that the common suction type centrifugal pump has no self-priming capacity, and can meet the requirement of self-priming conveying of fluids below the pump level in various industries. When general large-flow liquid is conveyed, the self-filling centrifugal pump has excellent performance because of the advantages of simple structure, higher benefit, low noise, low manufacturing cost and the like.

However, in practical use, the self-priming centrifugal pump cannot be used particularly for some liquids with viscosity, and the viscosity of the liquid is greatly changed along with the change of temperature, particularly for conveying low-temperature (the viscosity of the liquid is increased at low temperature) and some liquids with viscosity.

The reason is as follows:

1. in order to adapt to low temperature and some viscosity liquid, the centrifugal pump needs to have larger suction force and an enlarged impeller to obtain larger inertial centrifugal force; meanwhile, the shaft power is increased, and the power of the motor is increased to make up the condition that the self-priming centrifugal pump operates at low temperature and with some viscous liquid; thus, certain flow speed and flow can be achieved, and the output liquid pressure is met. Especially in low temperature viscosity liquid, the output liquid pressure is large due to the poor liquidity of the liquid, thus increasing the shaft power and possibly overloading and burning the motor.

2. When the pump is just started, because the mixture proportion of air and liquid is different, the load force of the impeller is different, so that the unbalance of output pressure is caused, the power of the motor shaft is unbalanced, the operation of the motor is unstable, and the service lives of the impeller and the motor are greatly shortened.

3. Because when increasing the shaft power, when carrying high temperature liquid, that is to say when the viscosity of liquid changes by a wide margin into low viscosity liquid along with the change of temperature, the self priming pump is carried liquid and is expected to reach certain velocity of flow and flow, because liquid viscosity is little, and mobility is good, carries liquid pressure also for a short time. Therefore, the pressure difference between some viscosity liquid in a self-priming pump conveying low-temperature zone and the high-temperature low-viscosity liquid is large, the self-priming centrifugal pump cannot automatically adjust the output pressure, the pressure value of the output liquid cannot be kept to meet the working condition requirement all the time, and the equipment system is unstable.

4. In practical operation, especially for some liquid with viscosity and the viscosity of the liquid is changed greatly with the change of temperature, especially at low temperature and some viscosity liquid, the self-filling centrifugal pump drives the impeller on the rotating shaft to rotate due to the influence of its characteristics (the pump is operated by the rotating shaft of the motor, if there is no liquid in the pump and only air is, the density of the air is very low, the centrifugal force generated after the rotation is small, so the low pressure formed in the central area of the impeller is not enough to suck the liquid in the external storage tank into the pump, after a certain amount of liquid is added into the pump body, the pump shaft drives the impeller to rotate together to force the liquid among the blades to rotate, the liquid is thrown from the center of the impeller to the periphery under the action of inertial centrifugal force and obtains energy, so that the static pressure of the liquid flowing to the periphery of the impeller is increased, the flow velocity is increased, after the liquid leaves the impeller and enters the extrusion cavity in the pump body, the liquid is decelerated due to the gradual expansion of the flow channel of the pump body, most of kinetic energy is converted into static pressure, and then the liquid with higher pressure enters the discharge pipeline from the discharge port of the pump and is conveyed to a required place. ) In the process, the self-priming centrifugal pump needs to discharge air in the pump body and the inlet pipe for a long time, generally more than 5-10 minutes, or the air cannot be discharged completely, the suction force of the impeller is far lower than one atmospheric pressure, so that the suction lift of the centrifugal pump is very small and cannot meet daily use, and particularly, the liquid cannot be used at a height of 5-9 meters below the pump level.

Therefore, it is important to find a working method of the drainage type constant pressure self-priming pump with the external open pressure relief valve body, which can be suitable for conveying low-temperature and high-viscosity liquid and can also be suitable for conveying high-temperature and low-viscosity liquid, and has stable operation of the motor and stable output pressure.

Disclosure of Invention

The invention aims to overcome the defects and provides a working method of the drainage type constant-pressure self-priming pump with the external open pressure relief valve body, which can adapt to the transportation of low-temperature and high-viscosity liquid and also adapt to the transportation of high-temperature and low-viscosity liquid, the motor runs stably, and the output pressure is stable, so that the system runs reliably, has constant pressure, is not easy to damage and runs stably.

The purpose of the invention is realized as follows:

the working method of the drainage type constant-pressure self-priming pump with the external open type pressure relief valve body is characterized by comprising a pump body and a motor, wherein the pump body and the motor are jointly installed on a pump base and are arranged on the left and the right, the pump body comprises a pump shell, the pump base is connected to the bottom of the pump shell, a suction cavity, an impeller cavity, a pressing cavity and a pressure relief cavity are arranged in the pump shell, the motor comprises a motor main body, the pump base is connected to the bottom of the motor main body, a motor flange is arranged at the left end of the motor main body and fixedly connected with a pump flange on the left side of the motor main body through bolts, a motor rotating shaft is stretched out to the left of the motor main body, the motor rotating shaft stretches out to the left of the motor flange, and sequentially penetrates through the pump flange and the impeller to the left, the left end of a rotating shaft of the motor is fixedly connected with the left end face of the impeller through an impeller fixing screw, a drainage pump is further arranged in the middle of the left end of the pump body, a drainage pump inlet pipeline is arranged in the pump body on the outer side of the inlet check valve and connected with an inlet of the drainage pump, a drainage pump outlet pipeline is arranged in the pump body on the inner side of the inlet check valve, an outlet of the drainage pump is connected with a drainage pump outlet pipeline, namely, fluid entering from a pump inlet can be divided into two parts, one part directly enters the suction cavity through the inlet check valve, and the other part enters the suction cavity through the drainage pump inlet pipeline, the drainage pump and the drainage pump outlet pipeline; the specific working method comprises the following steps:

the drainage pump rotates together due to the rotation of the motor rotating shaft, air in the pump inlet is rapidly discharged into the pump body and then discharged out of the pump outlet through the impeller, the motor rotating shaft rotates to drive the impeller and the drainage pump, when the pump is just started, because the suction cavity and the pump inlet of the pump body are the same as the atmospheric pressure, when the impeller rotates at a high speed, the air in the suction cavity is discharged out of the pump outlet through the centrifugal force of the impeller, at the moment, the suction cavity is negative pressure, the pressure of the pump inlet is atmospheric pressure and is larger than the pressure of the suction cavity, so that the inlet check valve is opened, meanwhile, the drainage pump also rotates together, simultaneously, the air in the pump inlet is introduced into the suction cavity, and then the air is discharged out of the pump outlet through the impeller, and the process is repeated; until the pressures of the suction cavity and the pump inlet are balanced, the inlet check valve is closed, the rotation of the drainage pump enables the air at the pump inlet to be continuously discharged into the suction cavity through the drainage pump, and then the impeller discharges the air out of the pump outlet, so that the air in the suction cavity is infinitely exhausted in a circulating manner; the liquid in the external storage tank is sucked into the suction cavity through the drainage pump, and then the liquid with higher pressure is obtained by the rotating impeller under the action of high-speed inertial centrifugal force, enters the discharge pipeline from the pump outlet and is conveyed to a required place.

Preferably, the drainage pump comprises a drainage pump shell, a driven gear and a driving gear which are arranged up and down are arranged in the drainage pump shell, the driven gear and the driving gear are meshed with each other, the height of the mutual meshing is called the meshing height, the driven gear penetrates through a transverse driven shaft, the driving gear penetrates through a transverse driving shaft, the left end and the right end of the driven shaft are arranged in a driven shaft cavity of the upper half section in the drainage pump shell through bearings, the inner diameter of the driven shaft cavity is matched with the size of the driven gear, the left end and the right end of the driving shaft are arranged in a driving shaft cavity of the lower half section in the shell of the drainage pump through bearings, the inner diameter of the driving shaft cavity is matched with the size of the driving gear, the right end of the driving shaft penetrates out of the drainage pump shell and is in power connection with a rotating shaft of the motor through a linkage shaft, and a driving shaft seal is arranged at the joint of the driving shaft and the linkage shaft; the drainage pump shell includes the drainage pump shell end cover of the drainage pump shell main casing body and the left end of half section on the right side, and drainage pump shell end cover passes through the screw fixation on the drainage pump shell main casing body, drainage pump shell right-hand member still is equipped with inlet opening, exit hole and initiative shaft hole left, inlet opening intercommunication feed liquor oral cavity, the oral cavity of feed liquor highly be a little higher than the meshing height and with the axle core staggered arrangement in driven shaft chamber, exit hole intercommunication liquid oral cavity, the oral cavity of liquid highly be a little less than the meshing height and with the axle core staggered arrangement in initiative axle chamber, the axis of driven shaft forms a vertical axis plane with the axis of driving shaft, inlet opening and exit hole are located axis plane front and back both sides respectively, initiative shaft hole and driving shaft are arranged with one heart. The inlet pipeline of the drainage pump is connected with the inlet hole, and the outlet pipeline of the drainage pump is connected with the outlet hole.

Preferably, the lower section of the right side of the pump shell is provided with a pump body flange, the left side of the pump body flange is provided with an impeller cavity, an impeller is arranged in the impeller cavity, the suction cavity is positioned at the upper left side of the impeller cavity and is communicated with the inlet at the left end of the impeller cavity, the extrusion cavity is communicated with the top of the impeller cavity, the pressure relief cavity is communicated with the bottom of the impeller cavity, the pump shell at the left side of the suction cavity is provided with a pump inlet, the pump inlet is provided with an inlet check valve, the pump shell at the top of the extrusion cavity is provided with a pump outlet, the bottom of the suction cavity is provided with a liquid return port leftwards and rightwards, the left end of the pressure relief cavity is upwards provided with a pressure relief port, the pressure relief port is communicated from top to bottom, the liquid return port is positioned at the upper right side of the pressure relief port, a pressure relief valve body mounting position is formed in the area between the liquid return port and the pressure relief port, the pressure relief valve body mounting position is communicated with the left end surface of the pump shell, an outward-opened pressure relief valve body is arranged in the pressure relief valve body mounting position, the outward opening type pressure relief valve body is provided with a pressure relief inlet and a pressure relief outlet, the pressure relief inlet is communicated with the pressure relief port, and the pressure relief outlet is communicated with the liquid return port.

Preferably, the outward opening type pressure relief valve body is a detachable outward opening type adjustable pressure relief valve;

the detachable outward-opening type adjustable pressure relief valve comprises a valve body shell, an adjusting screw rod, a spring, a valve core, a connecting rod, a locking nut, a clamp spring, a spring pressing plate, a choke plug screw and a fixed pin, wherein the right half section of the bottom of the valve body shell is provided with a pressure relief inlet, the right end of the valve body shell is provided with a pressure relief outlet, the inner wall of the valve body shell on the left side of the pressure relief outlet is convexly provided with a circle of valve core bayonet, the left end of the valve body shell is outwards provided with a valve body flange which is connected with a pump shell through a connecting bolt, the inner wall of the left section of the valve body shell is provided with an internal thread, the periphery of the adjusting screw rod is provided with an external thread, the adjusting screw rod is screwed into the valve body shell from left to right to be in threaded fit with the valve body shell, the left section of the adjusting screw rod is positioned on the left outer side of the valve body shell, the adjusting screw rod is of a hollow structure which is communicated from left to right, and a transverse spring is arranged in the right section of the adjusting screw rod, the connecting rod is arranged in the spring in a penetrating mode, the right end of the connecting rod is connected with the valve core, the appearance of the valve core is matched with the inner cavity of the valve body shell, the valve core is located on the right side of the valve core bayonet and can be limited by the valve core bayonet, a circle of clamp spring limiting groove is formed in the inner wall of the right end of the adjusting screw rod and is inwards concave, the clamp spring is arranged in the clamp spring limiting groove, the right end of the spring is in contact connection with the clamp spring, a spring pressing plate is sleeved at the left end of the connecting rod, the right side of the spring pressing plate is in contact connection with the left end of the spring, a fixing pin is arranged at the end portion of the left connecting rod of the spring pressing plate, a first sealing ring is arranged on the outer ring of the right end of the adjusting screw rod, a second sealing ring is arranged between the adjusting screw rod and the blind screw rod, and the locking nut is arranged on the left section of the adjusting screw rod and is tightly close to the outer wall of the left side of the flange of the valve body so as to lock the position of the adjusting screw rod.

Preferably, the outward opening type pressure relief valve body is an outward opening type adjustable pressure relief valve;

the outward opening type adjustable relief valve is different from a detachable outward opening type relief valve in that a valve body shell does not exist, the outward opening type adjustable relief valve comprises a valve body shell, an adjusting screw rod, a spring, a valve core, a connecting rod, a locking nut, a clamp spring, a spring pressing plate, a choke plug screw and a fixing pin, an internal thread is arranged on the inner wall of the left section of a pump shell at the installation position of the pressure relief valve body, an external thread is arranged on the periphery of the adjusting screw rod, the adjusting screw rod is screwed into the installation position of the pressure relief valve body from left to right to be matched with the internal thread, the left section of the adjusting screw rod is positioned on the left outer side of the installation position of the pressure relief valve body, a circle of valve core bayonet is convexly arranged on the inner wall of the installation position of the pressure relief valve body on the left side of a pressure relief outlet, the adjusting screw rod is of a hollow structure which is communicated from left to right, a transverse spring is arranged in the right section of the adjusting screw rod, the connecting rod is penetrated in the spring, the right end of the connecting rod is connected with the valve core, and the appearance of the valve core is matched with the inner cavity of the installation position of the pressure relief valve body, the valve core is located on the right side of the valve core bayonet and can be limited by the valve core bayonet, a circle of clamp spring limiting groove is inwards concave on the inner wall of the right end of the adjusting screw rod, the clamp spring is arranged in the clamp spring limiting groove, the right end of the spring is in contact connection with the clamp spring, a spring pressing plate is sleeved at the left end of the connecting rod, the right side of the spring pressing plate is in contact connection with the left end of the spring, a fixing pin is arranged at the end of the connecting rod on the left side of the spring pressing plate, a first sealing ring is arranged on the outer ring of the right end of the adjusting screw rod, a choke plug screw is screwed in the left end of the adjusting screw rod, a second sealing ring is arranged between the adjusting screw rod and the choke plug screw, and the locking nut is screwed on the left section of the adjusting screw rod and locks the position of the adjusting screw rod by abutting against the outer wall on the left side of the pressure relief valve body mounting position.

Compared with the prior art, the invention has the beneficial effects that:

the self-priming pump adopts the externally-opened pressure relief valve body, so that liquid initially entering the impeller cavity of the self-priming pump can return to the suction cavity through the externally-opened pressure relief valve body, the self-priming pump impeller cavity is quickly filled with the liquid, the impeller is prevented from idling, the conveying capacity of the impeller is improved, and the self-priming pump is suitable for conveying liquid incapable of viscosity by adjusting the adjusting screw rod of the externally-opened pressure relief valve body. The invention has the advantages of being suitable for conveying low-temperature and high-viscosity liquid, being suitable for conveying high-temperature and low-viscosity liquid, stably operating the motor and stabilizing the output pressure.

Drawings

Fig. 1 is a schematic structural view of a drainage type constant pressure self-priming pump with an outward opening pressure relief valve body in embodiment 1.

Fig. 2 is a schematic view of the detachable externally-opened adjustable relief valve in embodiment 1.

Fig. 3 is another state diagram of fig. 2.

Fig. 4 is an exploded view of fig. 2.

Fig. 5 is a schematic structural view of a drainage type constant pressure self-priming pump with an outward opening pressure relief valve body in embodiment 2.

Fig. 6 is a schematic view of the detachable externally-opened adjustable relief valve in embodiment 2.

Fig. 7 is another state diagram of fig. 6.

Fig. 8 is an exploded view of fig. 6.

Fig. 9 is a schematic view of the drainage pump of fig. 1.

FIG. 10 is an exploded view of FIG. 9

FIG. 11 is a cross-sectional view of a pump.

Fig. 12 is a perspective cross-sectional view of a drainage pump.

Fig. 13 is a right side view of the drainage pump.

Wherein:

the drainage pump 400, the drainage pump shell 401, the drainage pump shell main shell 401.1, the drainage pump shell end cover 401.2, the driven gear 402, the driving gear 403, the driven shaft 404, the driving shaft 405, the inlet hole 406, the outlet hole 407, the driving shaft hole 408, the linkage shaft 409, the driven shaft cavity 410, the driving shaft cavity 411 and the driving shaft seal 412

The self-priming pump comprises a drainage type constant pressure self-priming pump 700 with an externally-opened pressure relief valve body, a pump body 701, a pump housing 701.1, a suction cavity 701.2, an impeller cavity 701.3, a pressing cavity 701.4, a pressure relief cavity 701.5, a pump body flange 701.6, an impeller 701.7, a pump inlet 701.8, an inlet check valve 701.9, a pump outlet 701.10, a defoamer 701.11, a liquid filling opening 701.12, a liquid filling opening bolt 701.13, a liquid discharging opening 701.14, a liquid discharging opening bolt 701.15, a liquid return opening 701.16, a pressure relief opening 701.17, a buffer cavity 701.18, a motor 702, a motor main body 702.1, a motor flange 702.2, a motor rotating shaft 702.3, an impeller fixing screw 702.4 and a pump base 703

Detachable outward-opening pressure relief valve body 640, valve body shell 641, adjusting screw rod 642, spring 643, valve core 644, connecting rod 645, locking nut 646, clamp spring 647, spring pressing plate 648 and bulkhead screw 649

An externally opening adjustable relief valve 650.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to the drawings, the invention relates to a flow-guiding type constant pressure self-priming pump 700 with an outward opening pressure relief valve body, which comprises a pump body 701 and a motor 702, wherein the pump body 701 and the motor 702 are jointly installed on a pump base 703, the pump body 701 and the motor 702 are arranged on the left and right, the pump body 701 comprises a pump housing 701.1, the bottom of the pump housing 701.1 is connected with the pump base 703, a suction cavity 701.2, an impeller cavity 701.3, a pressure relief cavity 701.4 and a pressure relief cavity 701.5 are arranged in the pump housing 701.1, the lower half section of the right side of the pump housing 701.1 is provided with a pump flange 701.6, the left side of the pump flange 701.6 is provided with the impeller cavity 701.3, the impeller cavity 701.3 is provided with an impeller 701.7, the suction cavity 701.2 is positioned above the left side of the impeller cavity 701.3 and is communicated with a left end inlet of the impeller cavity 701.3, the pressure relief cavity 701.4 is communicated with the top of the impeller cavity 701.3, the pressure relief cavity 701.5 is communicated with the bottom of the pump 701.3, the pump housing 701.2 is provided with a pump inlet 701.8, an inlet check valve 701.9 is arranged at a pump inlet 701.8, a pump outlet 701.10 is arranged on a pump housing 701.1 at the top of an extrusion cavity 701.4, a defoamer 701.11 is arranged at an extrusion cavity 701.4 right below the pump outlet 701.10, a buffer cavity 701.18 is arranged right below the defoamer 701.11, a filling port 701.12 is further arranged on the pump housing 701.1 at the top of the extrusion cavity 701.4, a filling port 701.12 is positioned at the left upper part of the extrusion cavity 701.4, a filling port bolt 701.13 is arranged at the filling port 701.12, a liquid discharging port 701.14 is arranged on the pump housing 701.1 at the left end of the pressure discharging cavity 701.5, a liquid discharging port bolt 701.15 is arranged at the liquid discharging port 701.14, a liquid return port 701.16 is arranged at the bottom of the suction cavity 701.2 leftwards, the liquid return port 701.16 is communicated left and right, a pressure relief port 701.17 is arranged upwards at the left end of the pressure discharging cavity 701.5, the pressure relief port 701.17 is communicated up and the liquid return port 701.16 is positioned at the right upper part of the pressure relief 701.17, a pressure relief valve body is formed between the pressure relief port 701.16 and the pressure relief port 701.17, the pressure relief valve body installation position communicates to the pump casing 701.1 left end face, is provided with an outward opening pressure relief valve body in the pressure relief valve body installation position, and outward opening pressure relief valve body has a pressure relief import 610.1 and a pressure relief export 610.2, and pressure relief import 610.1 communicates with pressure relief port 701.17, and pressure relief export 610.2 communicates with liquid return port 701.16.

The motor 702 comprises a motor body 702.1, the pump base 703 is connected to the bottom of the motor body 702.1, the left end of the motor body 702.1 is provided with a motor flange 702.2, the motor flange 702.2 passes through bolt fixed connection with the pump body flange 701.6 on the left side thereof, the motor body 702.1 stretches out to the left motor rotating shaft 702.3 and the motor rotating shaft 702.3 stretches out to the left of the motor flange 702.2, the motor rotating shaft 702.3 also passes through the pump body flange 701.6 and the impeller 701.4 to the left in sequence, and the left end of the motor rotating shaft 702.3 passes through the left end face fixed connection of the impeller fixing screw 702.4 and the impeller 701.7.

The left end middle part of the pump body 701 still is provided with a drainage pump 400, be provided with a drainage pump inlet pipeline 708 in the pump body 701 in the import check valve 701.9 outside, the entry of drainage pump 400 is connected to drainage pump inlet pipeline 708, be provided with a drainage pump outlet pipeline 709 in the pump body 701 of import check valve 701.9 inboard, drainage pump outlet pipeline 709 is connected to the export of drainage pump 400, and the fluid that pump inlet 701.8 got into that says so can divide two, and one directly gets into through import check valve 701.9 and inhales chamber 701.2, and another gets into again and inhales chamber 701.2 through drainage pump inlet pipeline 708, drainage pump 400 and drainage pump outlet pipeline 709.

The drainage pump 400 comprises a drainage pump shell 401, a driven gear 402 and a driving gear 403 which are arranged up and down are arranged in the drainage pump shell 401, the driven gear 402 and the driving gear 403 are meshed with each other, the height of the mutual meshing is called the meshing height, the driven gear 402 passes through a transverse driven shaft 404, the driving gear 403 passes through a transverse driving shaft 405, the left end and the right end of the driven shaft 404 are installed in a driven shaft cavity 410 of the upper half section in the drainage pump shell 401 through bearings, the inner diameter of the driven shaft cavity 410 is matched with the size of the driven gear 402, the left end and the right end of the driving shaft 405 are installed in a driving shaft cavity 411 of the lower half section in the drainage pump shell 401 through bearings, the inner diameter of the driving shaft cavity 411 is matched with the size of the driving gear, the right end of the driving shaft 405 penetrates out of the drainage pump shell 401 and is in power connection with a motor rotating shaft 702.3 through a linkage shaft 409, of course, the motor rotating shaft 702.3 may be driven by other power connection methods, and may rotate at the same speed or at different speeds. A driving shaft seal 412 is arranged at the joint of the driving shaft 405 and the linkage shaft 409; the drainage pump shell 401 includes the drainage pump shell end cover 401.2 of the drainage pump shell main casing 401.1 and the left end of half section on the right side in the figure, and drainage pump shell end cover passes through the screw fixation on the drainage pump shell main casing, drainage pump shell 401 right-hand member still is equipped with left inlet port 406, exit hole 407 and initiative shaft hole 408, inlet port 406 intercommunication feed liquor oral cavity, the height in feed liquor oral cavity is a little higher than the meshing height and with the axle core staggered arrangement in driven shaft chamber, exit hole 407 intercommunication feed liquor oral cavity, the height in feed liquor oral cavity be a little lower than the meshing height and with the axle core staggered arrangement in initiative shaft chamber, the axis of driven shaft 404 and the axis of driving shaft 405 form a vertical axis plane, inlet port 406 and exit hole 407 are located axis plane's front and back both sides respectively, initiative shaft hole 408 and driving shaft 405 are arranged with one heart. A drain pump inlet conduit 708 connects with the inlet port 406 and a drain pump outlet conduit 709 connects with the outlet port 407.

The working principle of the drainage pump 400 is as follows:

the drainage pump rotates together due to the rotation of the motor rotating shaft, and the drainage pump has good structural characteristic and sealing performance, and can quickly discharge air in the pump inlet into the pump body and then discharge the air out of the pump outlet through the impeller, the motor rotating shaft rotates to drive the impeller and the drainage pump, when the pump is started, because the suction cavity and the pump inlet of the pump body are the same as the atmospheric pressure, when the impeller rotates at high speed, the air in the suction cavity is discharged out of the pump outlet through the centrifugal force of the impeller, the suction cavity is at negative pressure, and the pump inlet is at the atmospheric pressure so as to be higher than the pressure of the suction cavity, the check valve at the inlet is opened, and simultaneously, the drainage pump also rotates together to introduce the air in the pump inlet into the suction cavity and discharge the air out of the pump outlet through the impeller, and the process is repeated; the inlet check valve is closed until the pressures of the suction cavity and the pump inlet are balanced, and due to the structural characteristics and good sealing property of the drainage pump, the rotation of the drainage pump enables the air at the pump inlet to be continuously discharged into the suction cavity through the drainage pump, and then the air is discharged out of the pump outlet through the impeller, so that the air in the suction cavity is infinitely exhausted in a repeated way; the liquid in the external storage tank is sucked into the suction cavity through the drainage pump, and then the liquid with higher pressure is obtained by the rotating impeller under the action of high-speed inertial centrifugal force, enters the discharge pipeline from the pump outlet and is conveyed to a required place.

1. Thus, the problem that a certain amount of liquid must be added into the pump body to ensure self-suction capability is solved; 2. the problem that the liquid cannot be used at a height of more than 5 to 9 meters below the level of the centrifugal pump is solved;

3. the problem that the time for exhausting the air in the pump body and the inlet pipe is long is solved, and the exhausting can be generally completed within a few seconds.

Example 1

The outward opening type pressure relief valve body is a detachable outward opening type adjustable pressure relief valve 640;

the detachable outward-opening type adjustable pressure relief valve 640 specifically comprises a valve body shell 641, an adjusting screw rod 642, a spring 643, a valve core 644, a connecting rod 645, a locking nut 646, a snap spring 647, a spring pressing plate 648, a choke plug screw 649 and a fixing pin, wherein the right half section of the bottom of the valve body shell 641 is provided with a pressure relief inlet 610.1, the right end of the valve body shell 641 is provided with a pressure relief outlet 610.2, the inner wall of the valve body shell 641 at the left side of the pressure relief outlet 610.2 is convexly provided with a circle of valve core bayonet, the left end of the valve body shell 641 is outwards provided with a valve body flange 641.1, the valve body flange 641.1 is connected with a pump shell 701.1 through a connecting bolt, the inner wall of the left section of the valve body shell 641 is provided with internal threads, the periphery of the adjusting screw rod 642 is provided with external threads, the adjusting screw rod 642 is screwed into the valve body shell 641 to the right side and is in threaded fit with the valve body shell 641, the left section of the adjusting screw rod 642 at the left outer side of the valve body shell 641, and the adjusting screw rod is a hollow structure with a through left side and right side, a transverse spring 643 is arranged in the right section of the adjusting screw rod 642, a connecting rod 645 penetrates through the spring 643, the right end of the connecting rod 645 is connected with a valve core 644, the appearance of the valve core 644 is matched with the inner cavity of the valve body shell 641, the valve core 644 is located on the right side of a valve core bayonet and can be limited by the valve core bayonet, a circle of snap spring limiting groove is inwards recessed in the inner wall of the right end of the adjusting screw rod 642, a snap spring 647 is arranged in the snap spring limiting groove, the right end of the spring 643 is in contact connection with the snap spring 647, a spring pressing plate 648 is sleeved at the left end of the connecting rod 648, the right end of the spring pressing plate 648 is in contact connection with the left end of the spring 643, a fixing pin is arranged at the end of the connecting rod 645 on the left side, a first sealing ring is arranged on the outer ring of the right end of the adjusting screw rod 642, a second sealing ring is arranged between the adjusting screw rod 642 and the blind screw 649, a locking nut 646 is screwed on the left section of the adjusting screw rod 642 and abuts against the outer wall of the left side of the valve body flange 641.1, so that the adjusting screw rod 642 can enable the adjusting screw rod 642 to be tightly The position of (1) is locked, and the extension and contraction of the spring 643 are suitable for the liquid return of a certain viscosity liquid or a certain pressure liquid.

Example 2

The outward opening type pressure relief valve body is an outward opening type adjustable pressure relief valve 650;

the outward opening type adjustable pressure relief valve 650 is different from the detachable outward opening type pressure relief valve 640 in that a valve body shell 641 does not exist, the outward opening type adjustable pressure relief valve 650 comprises the valve body shell 641, an adjusting screw rod 642, a spring 643, a valve core 644, a connecting rod 645, a locking nut 646, a snap spring 647, a spring pressing plate 648, a closed head screw 649 and a fixing pin, an inner thread is arranged on the inner wall of the left section of a pump shell 701.1 at the installation position of the pressure relief valve body, an outer thread is arranged on the periphery of the adjusting screw rod 642, the adjusting screw rod 642 is screwed into the installation position of the pressure relief valve body from left to right to be matched with the inner thread, the left section of the adjusting screw rod 642 is positioned on the left outer side of the installation position of the pressure relief valve body, a circle of a valve core bayonet is convexly arranged on the inner cavity wall of the installation position of the pressure relief valve body on the left of a pressure relief outlet 610.2, the adjusting screw rod 642 is of a hollow structure which is communicated from left to right, a transverse spring 643 is arranged in the right section of the adjusting screw rod 642, and a connecting rod 645 is penetrated, the right end of a connecting rod 645 is connected with a valve core 644, the shape of the valve core 644 is matched with the inner cavity of the mounting position of the pressure relief valve body, the valve core 644 is positioned on the right side of the valve core bayonet and can be limited by the valve core bayonet, the inner wall of the right end of an adjusting screw rod 642 is inwards provided with a circle of snap spring limiting groove, a snap spring 647 is arranged in the snap spring limiting groove, the right end of a spring 643 is in contact connection with the snap spring 647, the left end of the connecting rod 645 is sleeved with a spring pressing plate 648, the right side of the spring pressing plate 648 is in contact connection with the left end of the spring 643, the end of the connecting rod 645 on the left side of the spring pressing plate 648 is provided with a fixing pin, the outer ring of the right end of the adjusting screw rod 642 is provided with a first sealing ring, the left end of the adjusting screw rod 642 is screwed into a blind screw 649, a second sealing ring is arranged between the adjusting screw rod 642 and the blind screw 649, a locking nut 646 is screwed on the left section of the adjusting screw rod 642 and abuts against the outer wall of the mounting position on the left side of the mounting position of the pressure relief valve body, the extension and contraction of the spring 643 are suitable for the return of a liquid with a certain viscosity or a liquid under pressure.

The working principle is as follows:

when the motor is started, the rotating shaft of the motor rotates to drive the impeller to rotate, and if air exists in the pump body, the air density is low, and the centrifugal force generated after the rotation is small, so that the low pressure formed in the central area of the impeller is not enough to suck the liquid in the external storage tank into the pump body; therefore, after a certain amount of liquid is added into the pump body, the motor power can drive the impeller to force the liquid among the impeller blades to rotate, the liquid is thrown from the center of the impeller to the periphery under the action of inertial centrifugal force and obtains energy, so that the static pressure of the liquid flowing to the periphery of the impeller is increased, the flow rate is increased, the liquid is decelerated due to the gradual expansion of a flow passage of the pump body after leaving the impeller and entering a pressing cavity in the pump body, most of kinetic energy is converted into the static pressure, and then the liquid with higher pressure enters a discharge pipeline from the pump outlet and is conveyed to a required place.

When the liquid is thrown from the center of the impeller to the periphery, a low-pressure area is generated in the center of the impeller, the pressure above the liquid level of the storage tank is greater than the pressure of the suction port of the pump, so that the check valve is automatically opened in one direction, the liquid is sucked into the center of the impeller, the liquid has self-sealing capacity in the pump body as long as the impeller rotates continuously, the liquid is loaded with air and is sent to the extrusion cavity together, air and the liquid are separated out in the bubble eliminator in the pump body, the air is discharged from the pump outlet, the liquid is remained in the extrusion cavity until the air in the pump inlet and the suction cavity is completely discharged through the pump outlet, the liquid is continuously sucked and discharged, and the liquid is continuously conveyed out.

When the pressure of the liquid exceeds the set pressure, the liquid pushes a valve core of the pressure relief valve body to compress a spring in the pressure relief valve body, and high-pressure liquid enters from a pressure relief inlet and then is discharged from a pressure relief outlet to enter into a suction cavity; the larger the pressure is, the larger the compression of the spring in the pressure relief valve body is, the larger the opening area of the valve core and the pressure relief outlet of the pressure relief valve body is, so that the larger the circulating area is, and the flow rate is increased therewith. When the pressure of the liquid is lower than the set pressure, the spring in the pressure relief valve body resets, the valve core of the pressure relief valve body is closed, and the liquid cannot enter the pressure relief outlet through the pressure relief inlet and is discharged to the suction cavity. The strength and the pressure of the spring can be adjusted by adjusting the adjusting screw rod, and the pressure of the valve core on the pressure relief inlet of the valve body can be adjusted, namely the pressure and the flow of pressure relief can be continuously adjusted. The locking nut locks the adjusting screw rod after the technological requirement of pressure relief is adjusted by the adjusting screw rod. The pressure relief valve body can be an independent device and is embedded on the pump body to control the pressure and flow of the pump, so that the aim of constant pressure output of the pump liquid is fulfilled.

The above is only a specific application example of the present invention, and the protection scope of the present invention is not limited in any way. All the technical solutions formed by equivalent transformation or equivalent replacement fall within the protection scope of the present invention.

Claims

1. The working method of the drainage type constant-pressure self-priming pump with the external open type pressure relief valve body is characterized by comprising a pump body and a motor, wherein the pump body and the motor are jointly installed on a pump base and are arranged on the left and the right, the pump body comprises a pump shell, the pump base is connected to the bottom of the pump shell, a suction cavity, an impeller cavity, a pressing cavity and a pressure relief cavity are arranged in the pump shell, the motor comprises a motor main body, the pump base is connected to the bottom of the motor main body, a motor flange is arranged at the left end of the motor main body and fixedly connected with a pump flange on the left side of the motor main body through bolts, a motor rotating shaft is stretched out to the left of the motor main body, the motor rotating shaft stretches out to the left of the motor flange, and sequentially penetrates through the pump flange and the impeller to the left, the left end of a rotating shaft of the motor is fixedly connected with the left end face of the impeller through an impeller fixing screw, a drainage pump is further arranged in the middle of the left end of the pump body, a drainage pump inlet pipeline is arranged in the pump body on the outer side of the inlet check valve and connected with an inlet of the drainage pump, a drainage pump outlet pipeline is arranged in the pump body on the inner side of the inlet check valve, an outlet of the drainage pump is connected with a drainage pump outlet pipeline, namely, fluid entering from a pump inlet can be divided into two parts, one part directly enters the suction cavity through the inlet check valve, and the other part enters the suction cavity through the drainage pump inlet pipeline, the drainage pump and the drainage pump outlet pipeline; the specific working method comprises the following steps:

2. The working method of the drainage type constant pressure self-priming pump with the external open pressure relief valve body as claimed in claim 1, wherein the drainage pump comprises a drainage pump housing, a driven gear and a driving gear are arranged in the drainage pump housing, the driven gear and the driving gear are meshed with each other, the height of the mutual meshing is called as the meshing height, the driven gear passes through a transverse driven shaft, the driving gear passes through a transverse driving shaft, the left end and the right end of the driven shaft are mounted in a driven shaft cavity of the upper half section in the drainage pump housing through bearings, the inner diameter of the driven shaft cavity is matched with the size of the driven gear, the left end and the right end of the driving shaft are mounted in a driving shaft cavity of the lower half section in the drainage pump housing through bearings, the inner diameter of the driving shaft cavity is matched with the size of the driving gear, the right end of the driving shaft penetrates out of the drainage pump housing and is connected with the rotating shaft of the motor through a linkage shaft, a driving shaft seal is arranged at the joint of the driving shaft and the linkage shaft; the drainage pump shell comprises a drainage pump shell main shell body at the right half section and a drainage pump shell end cover at the left end, the drainage pump shell end cover is fixed on the drainage pump shell main shell body through screws, the right end of the drainage pump shell is also provided with a left inlet hole, a left outlet hole and a driving shaft hole, the inlet hole is communicated with a liquid inlet cavity, the height of the liquid inlet cavity is slightly higher than the meshing height and is arranged in a staggered way with the shaft core of the driven shaft cavity, the outlet hole is communicated with the liquid outlet cavity, the height of the liquid outlet cavity is slightly lower than the meshing height and is arranged in a staggered way with the shaft core of the driving shaft cavity, the axis of the driven shaft and the axis of the driving shaft form a vertical axis plane, the inlet hole and the outlet hole are respectively positioned at the front side and the rear side of the axis plane, the driving shaft hole and the driving shaft are arranged concentrically, an inlet pipeline of the drainage pump is connected with the inlet hole, and an outlet pipeline of the drainage pump is connected with the outlet hole.

3. The operation method of the drainage type constant pressure self-priming pump with the external open type pressure relief valve body according to claim 1, wherein the lower section of the right side of the pump housing is provided with a pump body flange, the left side of the pump body flange is an impeller cavity, an impeller is arranged in the impeller cavity, the suction cavity is positioned at the upper left of the impeller cavity and is communicated with the inlet at the left end of the impeller cavity, the extrusion cavity is communicated with the top of the impeller cavity, the pressure relief cavity is communicated with the bottom of the impeller cavity, the pump housing at the left side of the suction cavity is provided with a pump inlet, the pump inlet is provided with an inlet check valve, the pump housing at the top of the extrusion cavity is provided with a pump outlet, the bottom of the suction cavity is provided with a liquid return port at the left and right, the left end of the pressure relief cavity is provided with a pressure relief port upward, the pressure relief port is communicated with the upper and lower right, and the area between the liquid return port and the pressure relief port forms a pressure relief valve body installation position, the pressure relief valve body installation position communicates to pump casing left end face, is provided with an outward opening pressure relief valve body in the pressure relief valve body installation position, and outward opening pressure relief valve body has a pressure release import and a pressure release export, pressure release import and pressure release mouth intercommunication, pressure release export and liquid return mouth intercommunication.

4. The method of claim 3, wherein the externally-open pressure relief valve body is a detachable externally-open adjustable pressure relief valve;

5. The method of claim 3, wherein the externally-open pressure relief valve body is an externally-open adjustable pressure relief valve;