Two-stage water ring pump

Abstract

The utility model provides a two-stage water ring pump, and belongs to the technical field of pumps. The double-stage water ring pump solves the problem that in the prior art, a double-stage water ring pump is low in use reliability. The two-stage water ring pump comprises a pump shell with an air inlet and an air outlet, a front pump cover and a rear pump cover, the front pump cover and the rear pump cover are connected to the two ends of the pump shell respectively, the front pump cover is communicated with the air inlet, and the rear pump cover is communicated with the air outlet. A front-stage pump cavity communicated with the front pump cover through a front-stage air suction and exhaust disc and a rear-stage pump cavity communicated with the rear pump cover through a rear-stage air suction and exhaust disc are formed in the pump shell, a communicating pipe communicated with the front pump cover and the rear pump cover is further arranged on the pump shell, and an air exhaust pipe is connected to an air exhaust opening of the pump shell. An overflow pipe for communicating the exhaust pipe with the communicating pipe is arranged between the exhaust pipe and the communicating pipe, and an overflow valve for unidirectionally conducting airflow in the overflow pipe to the exhaust pipe is arranged on the overflow pipe. The double-stage water ring pump has the advantage that the use reliability of the double-stage water ring pump can be improved.

Description

TECHNICAL FIELD

[0001] The utility model belongs to pump technical field relates to a two-stage water ring pump. BACKGROUND

[0002] Water ring pump (i.e. water ring vacuum pump) is equipped with eccentric rotor with fixed blade, is thrown to the stator wall with liquid, and the liquid forms the liquid ring concentric with the stator, and the liquid ring and rotor blade constitute the variable volume of a kind of rotary variable volume vacuum pump.For Chinese patent document discloses a two-stage water ring pump (grant announcement number: CN202811403U), including main shaft, front bearing gland, rear bearing gland, the front bearing gland and rear bearing gland are located at the both ends of the main shaft respectively, the right side of the rear bearing gland is equipped with rear pump cover, the left side of the front bearing gland is equipped with front pump cover, rear pump cover and front pump cover between are sequentially equipped with rear stage pump body and front stage pump body, the rear stage pump body is equipped with rear stage impeller, the front stage pump body is equipped with front stage impeller, the right side of the front bearing gland is connected with shaft coupling, the rear stage pump body is connected with the rear stage suction and exhaust disc, the front stage pump body is connected with the front stage suction and exhaust disc, rear pump cover and front pump cover between are connected with gas guide pipe.

[0003] The two-stage water ring pump has the following deficiencies in use: when using, the two-stage water ring pump takes in air from the air suction end, and then the compressed gas (first stage) at the front stage impeller end is delivered to the rear stage impeller end through the gas guide pipe, and then the compressed gas (second stage) at the rear stage impeller end is discharged through the exhaust port, when the pressure of the compressed gas (first stage) in the front stage pump body reaches 0.05MPa to 0.1MPa, the pressure of the compressed gas entering the rear stage pump body through the gas guide pipe will exceed 0.1MPa, and the compressed gas with high air pressure is easy to cause damage to the rear stage impeller in the rear stage pump body, and even cause cracking of the rear stage impeller. SUMMARY

[0004] The utility model discloses a two-stage water ring pump to solve the above problems of the prior art. The technical problem to be solved by the utility model is how to improve the use reliability of the two-stage water ring pump.

[0005] The object of the utility model can be realized by the following technical schemes:

[0006] The utility model provides a double stage water ring pump, including the pump shell with air inlet and exhaust port and the front pump cover and rear pump cover who links respectively in the both ends of pump shell, the front pump cover communicates with the air inlet, the rear pump cover communicates with the exhaust port, the pump shell has the front stage pump cavity who communicates with the front pump cover through the front stage suction exhaust disc and the rear stage pump cavity who communicates with the rear pump cover through the rear stage suction exhaust disc in, the pump shell still is equipped with the communication pipe who communicates the front pump cover and rear pump cover, its characterized in that, the exhaust pipe is connected on the exhaust port of pump shell, and the overflow pipe who communicates both is equipped between the exhaust pipe and communication pipe, and the overflow valve for making the one-way conduction of the airflow in overflow pipe to exhaust pipe is arranged on the overflow pipe.

[0007] When the pressure of the compressed gas in the front stage pump cavity exceeds 0.1 MPa during the use of the double stage water ring pump, the overflow valve on the overflow pipe of the double stage water ring pump can automatically open to make the compressed gas in the front stage pump cavity directly discharge to the exhaust pipe through the overflow pipe without passing through the rear stage pump cavity. When the pressure of the compressed gas in the front stage pump cavity drops to less than 0.1 MPa, the overflow valve can automatically close to make the compressed gas in the front stage pump cavity discharge to the rear stage pump cavity through the communication pipe for further two-stage compression and then discharge through the exhaust pipe. This avoids the compressed gas with high pressure from damaging the rear stage impeller in the rear stage pump body, thereby improving the use reliability of the double stage water ring pump.

[0008] In the double stage water ring pump, the overflow valve includes a valve seat connected with the overflow pipe, the valve seat has an air inlet hole communicated with the communication pipe and an air outlet hole communicated with the exhaust pipe, a cylinder is installed on the valve seat, a valve core is connected with the output shaft of the cylinder, and the valve core can open or close the air inlet hole of the valve seat. The overflow valve adopts a pneumatic valve, so that the structure of the overflow valve is simple and the one-way conduction of the airflow in the overflow pipe to the exhaust pipe can be better achieved. In addition, the overflow valve also adopts the following structure: a retractable spring is installed on the valve seat, the valve core is connected with the retractable spring, and the valve core can open or close the air inlet hole of the valve seat.

[0009] In the double stage water ring pump, the valve seat has a through hole arranged opposite to the air inlet hole, the output shaft of the cylinder is vertically arranged and passes through the through hole, a sealing ring is sleeved on the output shaft of the cylinder and abuts against the hole wall of the through hole, and the vertical section of the combination of the valve core and the output shaft of the cylinder is in the shape of inverted T. This makes the valve core better open or close the air inlet hole of the valve seat, and the sealing ring can prevent the airflow from flowing out of the gap between the output shaft of the cylinder and the hole wall of the through hole, thereby improving the use reliability of the double stage water ring pump.

[0010] In the double-stage water ring pump, a partition plate is arranged in the pump shell between the front-stage pump cavity and the rear-stage pump cavity, the partition plate is provided with an overflow channel communicating the rear-stage pump cavity with the outside, and a micro pneumatic valve is arranged on the partition plate to open or close the overflow channel. The micro pneumatic valve can switch the double-stage water ring pump between single-stage and double-stage. Specifically, when the overflow valve is opened and the micro pneumatic valve is closed, the compressed gas in the front-stage pump cavity is directly discharged to the exhaust pipe through the overflow pipe without passing through the rear-stage pump cavity, so that the double-stage water ring pump becomes a single-stage pump in actual use, which is more energy-saving. When the overflow valve is closed and the micro pneumatic valve is opened, the compressed gas in the front-stage pump cavity is discharged to the rear-stage pump cavity through the communication pipe for secondary compression, and then discharged through the exhaust pipe. When the air pressure in the rear-stage pump cavity is too high, the air flow in the rear-stage pump cavity can be discharged to the outside through the overflow channel, so as to avoid damage to the rear-stage impeller in the rear-stage pump body caused by the compressed gas with high air pressure, thereby improving the vacuum degree while ensuring the use reliability of the double-stage water ring pump.

[0011] In the double-stage water ring pump, the lower end of the exhaust pipe and the two ends of the communication pipe are provided with flange rings, and the lower end of the exhaust pipe and the two ends of the communication pipe are detachably connected to the pump shell through bolts penetrating the flange rings. The pump shell is provided with corresponding flange rings, which facilitates the disassembly and assembly of the exhaust pipe, the communication pipe and the overflow pipe connecting the two.

[0012] In the double-stage water ring pump, the length of the front-stage impeller in the front-stage pump cavity is greater than the length of the rear-stage impeller in the rear-stage pump cavity. The longer front-stage impeller can reduce the loss of gas flowing through the impeller, thereby improving the compression efficiency. The shorter rear-stage impeller is subjected to smaller centrifugal force and has more uniform stress distribution, thereby reducing the risk of cracking.

[0013] Compared with the prior art, the double-stage water ring pump has the advantages that when the pressure of the compressed gas in the front-stage pump cavity exceeds 0.1 MPa, the overflow valve on the overflow pipe of the double-stage water ring pump can automatically open to make the compressed gas in the front-stage pump cavity directly discharged to the exhaust pipe through the overflow pipe without passing through the rear-stage pump cavity. When the pressure of the compressed gas in the front-stage pump cavity drops to less than 0.1 MPa, the overflow valve can automatically close to make the compressed gas in the front-stage pump cavity discharged to the rear-stage pump cavity through the communication pipe for secondary compression, and then discharged through the exhaust pipe. This avoids damage to the rear-stage impeller in the rear-stage pump body caused by the compressed gas with high air pressure, thereby improving the use reliability of the double-stage water ring pump. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 is a sectional view of the double-stage water ring pump.

[0015] Figure 2 is Figure 1A local enlarged view at B.

[0016] Figure 3 is Figure 1 A local enlarged view at B.

[0017] Figure 4 is a schematic structural view of the utility model from top.

[0018] In the figure, 1, pump shell; 1a, air inlet; 1b, air outlet; 1c, front stage pump cavity; 1d, rear stage pump cavity; 2, communication pipe; 3, exhaust pipe; 4, overflow pipe; 5, overflow valve; 5a, valve seat; 5a1, air inlet hole; 5a2, air outlet hole; 5a3, through hole; 5b, valve core; 6, sealing ring; 7, partition plate; 7a, overflow channel; 8, micro pneumatic valve; 9, front stage impeller; 10, rear stage impeller; 11, cylinder; 11a, output shaft; 12, front pump cover; 13, rear pump cover; 14, front stage suction and exhaust disc; 15, rear stage suction and exhaust disc; 16, pump shaft. DETAILED DESCRIPTION

[0019] The following is a specific embodiment of the utility model and further describes the technical scheme of the utility model in combination with the drawings, but the utility model is not limited to these embodiments.

[0020] A two-stage water ring pump, referring to Figures 1-4 , comprising a pump shell 1 with an air inlet 1a and an air outlet 1b, a pump shaft 16 rotatably arranged in the pump shell 1, and a front pump cover 12 and a rear pump cover 13 connected at both ends of the pump shell 1 respectively, the front pump cover 12 is communicated with the air inlet 1a, the rear pump cover 13 is communicated with the air outlet 1b, the pump shell 1 has a front stage pump cavity 1c communicated with the front pump cover 12 through a front stage suction and exhaust disc 14 and a rear stage pump cavity 1d communicated with the rear pump cover 13 through a rear stage suction and exhaust disc 15, the pump shell 1 is further provided with a communication pipe 2 communicating the front pump cover 12 and the rear pump cover 13, the air outlet 1b of the pump shell 1 is connected with an exhaust pipe 3, the overflow pipe 4 communicating the exhaust pipe 3 and the communication pipe 2 is arranged between the exhaust pipe 3 and the communication pipe 2, and the overflow valve 5 for unidirectionally guiding the airflow in the overflow pipe 4 to the exhaust pipe 3 is arranged on the overflow pipe 4.

[0021] Referring to Figure 1 and Figure 4, specifically, the overflow valve 5 comprises a valve seat 5a connected with the overflow pipe 4, the valve seat 5a is provided with an inlet hole 5a1 communicated with the communication pipe 2 and an outlet hole 5a2 communicated with the exhaust pipe 3, a cylinder 11 is installed on the valve seat 5a, a valve core 5b is connected with the output shaft 11a of the cylinder 11, and the valve core 5b can open or close the inlet hole 5a1 of the valve seat 5a. More specifically, a pressure sensor is arranged in the front-stage pump cavity 1c, a controller is arranged on the valve seat 5a and electrically connected with the cylinder 11, when the pressure sensor detects that the pressure of the compressed gas in the front-stage pump cavity 1c drops to less than 0.1 MPa, the controller controls the output shaft 11a of the cylinder 11 to drive the valve core 5b to close the inlet hole 5a1 of the valve seat 5a, and when the pressure sensor detects that the pressure of the compressed gas in the front-stage pump cavity 1c rises to more than 0.1 MPa, the controller controls the output shaft 11a of the cylinder 11 to drive the valve core 5b to open the inlet hole 5a1 of the valve seat 5a.

[0022] Referring to Figure 1 and Figure 3 , more specifically, the valve seat 5a is provided with a through hole 5a3 arranged opposite to the inlet hole 5a1, the output shaft 11a of the cylinder 11 is vertically arranged and passes through the through hole 5a3, a sealing ring 6 is sleeved on the output shaft 11a of the cylinder 11, and the sealing ring 6 abuts against the hole wall of the through hole 5a3, and the vertical section of the combination of the valve core 5b and the output shaft 11a of the cylinder 11 is in inverted T shape.

[0023] Referring to Figure 1 and Figure 2 , further, a partition plate 7 is arranged in the pump shell 1 between the front-stage pump cavity 1c and the rear-stage pump cavity 1d, the partition plate 7 is provided with an overflow channel 7a communicated with the rear-stage pump cavity 1d and the outside, and a micro pneumatic valve 8 is arranged on the partition plate 7 for opening or closing the overflow channel 7a. Specifically, referring to Figure 2 , the micro pneumatic valve 8 comprises a micro cylinder installed on the partition plate 7, the output shaft of the micro cylinder is vertically arranged and connected with a cylindrical pin, and the micro cylinder drives the cylindrical pin to move up and down to open or close the overflow channel 7a.

[0024] Referring to Figure 1 and Figure 4 , more specifically, the lower end of the exhaust pipe 3 and the two ends of the communication pipe 2 are all provided with flange rings, and the lower end of the exhaust pipe 3 and the two ends of the communication pipe 2 are respectively detachably connected with the pump shell 1 through bolts passing through the flange rings; the length of the front-stage impeller 9 in the front-stage pump cavity 1c is greater than the length of the rear-stage impeller 10 in the rear-stage pump cavity 1d.

[0025] When the pressure of the compressed gas in the front stage pump cavity 1c exceeds 0.1 MPa, the overflow valve 5 on the overflow pipe 4 of the dual-stage water ring pump can be automatically opened to make the compressed gas in the front stage pump cavity 1c directly discharged to the exhaust pipe 3 through the overflow pipe 4 without passing through the rear stage pump cavity 1d, and when the pressure of the compressed gas in the front stage pump cavity 1c drops to less than 0.1 MPa, the overflow valve 5 can be automatically closed to make the compressed gas in the front stage pump cavity 1c discharged to the rear stage pump cavity 1d through the communication pipe 2 for two-stage compression and then discharged through the exhaust pipe 3, thereby avoiding damage of the compressed gas with high pressure to the rear stage impeller 10 in the rear stage pump body and improving the use reliability of the dual-stage water ring pump.

[0026] Meanwhile, the dual-stage water ring pump can be switched between single-stage and dual-stage by setting the micro pneumatic valve 8, specifically, when the overflow valve 5 is opened and the micro pneumatic valve 8 is closed, the compressed gas in the front stage pump cavity 1c is directly discharged to the exhaust pipe 3 through the overflow pipe 4 without passing through the rear stage pump cavity 1d, so that the dual-stage water ring pump becomes a single-stage pump in actual use, which is more energy-saving, and when the overflow valve 5 is closed and the micro pneumatic valve 8 is opened, the compressed gas in the front stage pump cavity 1c is discharged to the rear stage pump cavity 1d through the communication pipe 2 for two-stage compression and then discharged through the exhaust pipe 3, and when the pressure in the rear stage pump cavity 1d is too high, the gas flow in the rear stage pump cavity 1d can be discharged to the outside through the overflow channel 7a, thereby avoiding damage of the compressed gas with high pressure to the rear stage impeller 10 in the rear stage pump body and improving the vacuum degree while ensuring the use reliability of the dual-stage water ring pump.

[0027] The specific embodiments described herein are merely illustrative of the present application. Those skilled in the art can make various modifications or supplements to the described specific embodiments or adopt similar ways to replace them without departing from the spirit of the present application or exceeding the scope defined by the appended claims.

Claims

1. A double-stage water ring pump, comprising a pump shell (1) having an air inlet (1a) and an air outlet (1b), and a front pump cover (12) and a rear pump cover (13) connected to the two ends of the pump shell (1) respectively, the front pump cover (12) being communicated with the air inlet (1a), and the rear pump cover (13) being communicated with the air outlet (1b), the pump shell (1) having a front-stage pump cavity (1c) communicated with the front pump cover (12) through a front-stage suction and exhaust disc (14), and a rear-stage pump cavity (1d) communicated with the rear pump cover (13) through a rear-stage suction and exhaust disc (15), and the pump shell (1) further having a communication pipe (2) communicated with the front pump cover (12) and the rear pump cover (13), characterized in that, The exhaust port (1b) of the pump shell (1) is connected with an exhaust pipe (3), and an overflow pipe (4) is arranged between the exhaust pipe (3) and the communication pipe (2) to communicate the two pipes; the overflow pipe (4) is provided with an overflow valve (5) for unidirectionally guiding the airflow in the overflow pipe (4) to the exhaust pipe (3).

2. A two-stage water ring pump according to claim 1, characterized in that The overflow valve (5) comprises a valve seat (5a) connected with the overflow pipe (4), the valve seat (5a) is provided with an air inlet hole (5a1) communicated with the communication pipe (2) and an air outlet hole (5a2) communicated with the exhaust pipe (3), and a cylinder (11) is arranged on the valve seat (5a); the output shaft (11a) of the cylinder (11) is connected with a valve core (5b), and the valve core (5b) can open or close the air inlet hole (5a1) of the valve seat (5a).

3. A two-stage water ring pump according to claim 2, characterized in that The valve seat (5a) is provided with a through hole (5a3) arranged opposite to the air inlet hole (5a1) in the up-down direction, the output shaft (11a) of the cylinder (11) is vertically arranged and passes through the through hole (5a3), a sealing ring (6) is arranged on the output shaft (11a) of the cylinder (11), and the sealing ring (6) abuts against the hole wall of the through hole (5a3); and the vertical section of the combination of the valve core (5b) and the output shaft (11a) of the cylinder (11) is in inverted T shape.

4. A two-stage water ring pump according to claim 1 or 2 or 3, characterized in that, A partition plate (7) is arranged in the pump shell (1) between the front-stage pump cavity (1c) and the rear-stage pump cavity (1d), the partition plate (7) is provided with an overflow channel (7a) communicated with the rear-stage pump cavity (1d) and the outside, and a micro pneumatic valve (8) is arranged on the partition plate (7) to open or close the overflow channel (7a).

5. A double stage water ring pump as claimed in claim 1 or 2 or 3, wherein, The lower end of the exhaust pipe (3) and the two ends of the communication pipe (2) are provided with flange rings, and the lower end of the exhaust pipe (3) and the two ends of the communication pipe (2) are detachably connected to the pump shell (1) by bolts passing through the flange rings.

6. A double stage water ring pump as claimed in claim 1 or 2 or 3, wherein, The length of the front-stage impeller (9) in the front-stage pump cavity (1c) is greater than the length of the rear-stage impeller (10) in the rear-stage pump cavity (1d).

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