Dry-type variable-lead double-screw vacuum pump

Abstract

The invention relates to a dry-type variable-lead double-screw vacuum pump which comprises a main screw, an auxiliary screw, a double-row angular contact ball bearing and a vacuum breaking silencing assembly. And a mechanical sealing ring I and a mechanical sealing ring II are respectively arranged on a front shaft and a rear shaft of the main screw rod. The completely-sealed screw end face molded line is a completely-sealed screw end face molded line of brand new design, it is ensured that a pump body is free of leakage in the operation process, the working efficiency is improved, the service life is prolonged, the sealing performance is enhanced through a unique sealing structure, the maintenance cost is greatly reduced, and the service life of the pump body is prolonged. According to the optimized design of the end face profile of the screw, through a precise machining process, higher machining precision and matching degree are achieved, it is ensured that the stable sealing effect can still be kept under the conditions of high rotating speed and high load, and friction loss and energy consumption are reduced to the maximum extent.

Description

Technical Field

[0001] The invention relates to the technical field of vacuum pumps, in particular to a dry variable-lead twin-screw vacuum pump. Background Art

[0002] The twin-screw vacuum pump is a vacuum device that uses two screws to rotate synchronously and at high speed in opposite directions in the pump body to produce suction and exhaust effects. It is an updated version of the oil-sealed vacuum pump and can extract gases containing a large amount of water vapor and a small amount of dust. It is widely used in major domestic pharmaceutical and chemical companies.

[0003] For example, the document with publication number CN110701045B discloses a twin-screw vacuum pump. The twin-screw vacuum pump of the invention has a simple and compact structure and high precision. The front bearing mechanism and oil-slinging plate are arranged to prevent oil from seeping into the motor, making the twin-screw vacuum pump more compact, improving the screw power transmission accuracy and transmission efficiency, and making the whole machine run more smoothly and reliably.

[0004] For example, the document with publication number CN109505769A discloses a double-headed screw vacuum pump. In this invention, a screw with positive and negative spiral teeth structure welded on it is used to shorten the gas transportation distance, reduce gas reflux, greatly increase the gas transfer efficiency, and directly improve the working efficiency of the double-headed screw vacuum pump.

[0005] However, during the use of the dry variable-lead twin-screw vacuum pump, due to the transmission of the screw, the pump body is prone to leakage during operation, affecting work efficiency. At the same time, the vacuum pump will generate a lot of heat. If the heat is not dissipated in time, it will easily affect the service life of the vacuum pump. After the vacuum pump is used, a large amount of oxygen will exist in the pump. If it is not purged in time, it will cause oxidation reactions and corrosion in the vacuum pump. Summary of the invention

[0006] 1. Technical issues to be solved

[0007] In order to solve the above technical problems, the present invention provides a dry variable-lead twin-screw vacuum pump.

[0008] (II) Technical solution

[0009] Based on this, the present invention provides the following technical solutions: a dry variable lead twin-screw vacuum pump, including a main screw, a secondary screw, a mechanical seal ring 1, a mechanical seal ring 2, a double-row angular contact ball bearing, a vacuum breaking silencer assembly, a round nut 1, a pump casing, a gear pump casing, a mechanical thrust cover, a hexagon socket head screw 1, a pump casing 3, a synchronous gear, a gear mounting taper sleeve, a hexagon socket head screw 2, a round nut 2, a water jacket pump casing 1, a plugging pump casing 1, a plugging pump casing 2, a water jacket pump casing 2, a hexagon socket head screw 3, an oil cap, a hexagon socket head screw 4, an exhaust flange, a blowing flange, a nitrogen purge exhaust pipe, a cooling flange, a quick connector 1, a water jacket sealing gasket, an oil window, a sealing plug 1, a sealing plug 2, a quick connector 2, an air pressure reducing valve 2, a sealing ring, a hexagon socket head screw 7, and an air pressure reducing valve 1;

[0010] The front shaft and the rear shaft of the main screw are respectively provided with a mechanical seal ring 1 and a mechanical seal ring 2, and the front shaft and the rear shaft of the auxiliary screw are respectively provided with a mechanical seal ring 1 and a mechanical seal ring 2. A mechanical thrust cover is installed at the rear end of the mechanical seal ring 2 to provide higher wear resistance and corrosion resistance. The double sealing design combined with high-performance sealing materials greatly improves the stability and reliability of the equipment, ensuring that the excellent sealing effect can be maintained under long-term high-load operation. The rear end of the mechanical thrust cover is connected to a double-row angular contact ball bearing, and the mechanical thrust cover is locked and fixed with the inner side of the sealing pump housing 2 by a hexagon socket head screw 1, and a round nut 1 is provided at the rear end of the double-row angular contact ball bearing;

[0011] The main screw and the auxiliary screw are both placed inside the pump casing, the pump casing is locked and fixed with the rear end of the gear pump casing by means of a hexagon socket head screw seven, the gear pump casing is locked and fixed with the rear end of the pump casing three by means of a hexagon socket head screw seven, the outer side of the pump casing is wrapped with a water jacket pump casing one, the rear end of the water jacket pump casing one is installed with a plugging pump casing one, the rear end of the plugging pump casing one is fixed with a plugging pump casing two, the front end of the pump casing three is installed with a water jacket pump casing two, and the top of the pump casing three is provided with an oil cover;

[0012] The top of the pump housing is locked and fixed to the blowing flange by using hexagon socket head screw four, the water jacket pump housing is locked and fixed to the bottom of the water jacket sealing gasket by using hexagon socket head screw three, the top of the water jacket sealing gasket is provided with a cooling flange, the bottom of the gear pump housing is connected to an exhaust flange, and the middle of the blowing flange is connected to a nitrogen purge exhaust pipe.

[0013] Preferably, the main screw and the auxiliary screw are arranged parallel to each other, and the screw end profiles of the main screw and the auxiliary screw adopt a water drop profile, the screw end of the main screw and the screw end of the auxiliary screw contact and cooperate with each other, and a sealing ring is provided at the front end of the mechanical sealing ring 2 to ensure that the pump body is leak-free during operation, improve work efficiency, and extend service life.

[0014] Preferably, there are two groups of synchronous gears, and the synchronous gears are respectively arranged on the front shaft of the main screw and the front shaft of the auxiliary screw, and the two groups of synchronous gears are meshed with each other.

[0015] Preferably, the front end of the synchronous gear is connected to the gear mounting cone sleeve by using two hexagon socket head screws, and the front end of the gear mounting cone sleeve is provided with two round nuts.

[0016] Preferably, a vacuum breaking silencer assembly is installed on the top of the blowing flange, and an air pressure reducing valve 2 and an air pressure reducing valve 1 are arranged on the left and right sides of the pump housing 3.

[0017] Preferably, quick connector 1 is relatively arranged on the left and right sides of the gear pump housing, quick connector 2 is connected to the top of the gear pump housing, the rear end of the sealing pump housing 2 is connected to the oil window, sealing plug 1 is relatively arranged on the upper and lower sides of the oil window, and sealing plug 2 is embedded and installed on the upper and lower sides of the sealing pump housing 2.

[0018] Preferably, the rear end of the pump housing is provided with a strip inner groove, the surface of the pump housing is provided with an annular channel, and the surface of the pump housing is evenly distributed with flow guide protrusions, by optimizing the cooling path, effectively controlling the internal temperature of the equipment, using heat exchange technology and high-efficiency coolant, so that heat can be quickly transferred from key components to prevent overheating. Whether in high or low temperature environments, it can ensure stable and efficient operation of the vacuum pump.

[0019] Preferably, purge ports are provided at the top and bottom and left and right sides of the gear pump housing. The purge ports at the top and bottom are connected to quick connector 2, and the purge ports on the left and right sides are connected to quick connector 1. By optimizing the purge path and designing evenly distributed purge ports, an all-round, dead-angle-free purge effect is achieved, further improving the safety and durability of the equipment.

[0020] Preferably, the inner wall of the water jacket pump housing 1 is covered with a sound insulation pad, the double-row angular contact ball bearing adopts a double-row angular contact ball bearing with a protective cover, the quick connector 1 is a PC10-02SUS quick connector, and the quick connector 2 is a PACK-MEPY10 quick connector.

[0021] (III) Beneficial effects

[0022] Compared with the prior art, the present invention provides a dry variable lead twin-screw vacuum pump, which has the following beneficial effects:

[0023] This dry variable lead twin-screw vacuum pump adopts a newly designed completely sealed screw end profile to ensure that the pump body is leak-free during operation, improve work efficiency and extend service life. The unique sealing structure not only enhances the sealing performance, but also greatly reduces maintenance costs. The optimized design of the screw end profile achieves higher processing accuracy and matching through precise processing technology, ensuring that a stable sealing effect can be maintained under high speed and high load conditions, minimizing friction loss and energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0025] Figure 2 It is a schematic diagram of the explosion structure of the present invention;

[0026] Figure 3 This is a schematic diagram of the three-dimensional structure of the main screw and the auxiliary screw of the present invention;

[0027] Figure 4 It is a schematic diagram of the partial three-dimensional structure of the main screw and the auxiliary screw of the present invention;

[0028] Figure 5 This is a schematic diagram of the three-dimensional structure of the blowing flange of the present invention;

[0029] Figure 6 It is a schematic diagram of the internal structure of the present invention;

[0030] Figure 7 For the present invention Figure 3 A in the figure is an enlarged structural diagram.

[0031] In the figure: main screw-1, auxiliary screw-2, mechanical seal ring 1-3, mechanical seal ring 2-4, double row angular contact ball bearing-5, vacuum breaking silencer assembly-6, round nut 1-7, pump housing-8, gear pump housing-9, mechanical thrust cover-10, hexagon socket head screw 1-11, pump housing 3-12, synchronous gear-13, gear mounting cone sleeve-14, hexagon socket head screw 2-15, round nut 2-16, water jacket pump housing 1-17, plugging pump housing 1-18, plugging pump housing 2-19, Water jacket pump housing 2-20, hexagon socket head screw 3-21, oil cap -22, hexagon socket head screw 4-23, exhaust flange -24, air blowing flange -25, nitrogen purge exhaust pipe -26, cooling flange -27, quick connector 1-28, water jacket sealing gasket -29, oil sight glass -30, sealing plug 1-31, sealing plug 2-32, quick connector 2-33, air pressure reducing valve 2-34, sealing ring -35, hexagon socket head screw 7-36, air pressure reducing valve 1-37. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] See also Figure 1-Figure 7 , a dry variable lead twin-screw vacuum pump, specifically including the following embodiments:

[0034] Example 1

[0035] A dry variable lead twin-screw vacuum pump comprises a main screw 1, a secondary screw 2, a double-row angular contact ball bearing 5, a vacuum breaking silencer assembly 6, a pump housing 8, a mechanical thrust cover 10, a synchronous gear 13, a gear mounting cone sleeve 14, a round nut 2 16, a water jacket pump housing 1 17, a water jacket pump housing 20, a nitrogen purge exhaust pipe 26, and a cooling flange 27; the front shaft and the rear shaft of the main screw 1 are respectively provided with a mechanical seal 3 and a mechanical seal 2 4, the rear end of the mechanical thrust cover 10 is connected with a double-row angular contact ball bearing 5, the mechanical thrust cover 10 is locked and fixed with the inner side of the sealing pump housing 2 19 by a hexagon socket head screw 1 11, and the rear end of the double-row angular contact ball bearing 5 is provided with a round nut 1 7; the main screw 1 and the secondary screw 2 are both placed inside the pump housing 8, and the pump housing 8 is fixed with the gear pump housing 9 by a hexagon socket head screw 7 36. The rear end of the pump casing 8 is locked and fixed, the gear pump casing 9 is locked and fixed with the rear end of the pump casing three 12 by using hexagon socket cylindrical head screws seven 36, the outside of the pump casing 8 is wrapped with a water jacket pump casing 17, the rear end of the water jacket pump casing 17 is installed with a blocking pump casing 18, the rear end of the blocking pump casing 18 is fixed with a blocking pump casing two 19, the front end of the pump casing three 12 is installed with a water jacket pump casing two 20, and the top of the pump casing three 12 is provided with an oil cover 22; the top of the pump casing 8 is locked and fixed with the blowing flange 25 by using hexagon socket cylindrical head screws four 23, the water jacket pump casing 17 is locked and fixed with the bottom of the water jacket sealing gasket 29 by using hexagon socket cylindrical head screws three 21, the top of the water jacket sealing gasket 29 is provided with a cooling flange 27, the bottom of the gear pump casing 9 is connected with an exhaust flange 24, and the middle part of the blowing flange 25 is connected with a nitrogen purge exhaust pipe 26.

[0036] In this embodiment, the front shaft and the rear shaft of the auxiliary screw 2 are respectively provided with a mechanical seal ring 1 3 and a mechanical seal ring 2 4 , and a mechanical thrust cover 10 is installed at the rear end of the mechanical seal ring 2 4 .

[0037] In this embodiment, the main screw 1 and the auxiliary screw 2 are arranged parallel to each other, and the screw end profiles of the main screw 1 and the auxiliary screw 2 adopt a water drop profile, the screw end of the main screw 1 and the screw end of the auxiliary screw 2 are in contact and fit with each other, and a sealing ring 35 is provided at the front end of the mechanical sealing ring 24.

[0038] In this embodiment, there are two groups of synchronous gears 13, and the synchronous gears 13 are respectively arranged on the front shaft of the main screw 1 and the front shaft of the auxiliary screw 2, and the two groups of synchronous gears 13 are meshed with each other. The front end of the synchronous gear 13 is connected to the gear mounting cone sleeve 14 by a hexagon socket head screw 15, and the front end of the gear mounting cone sleeve 14 is provided with a round nut 16, and the top of the blowing flange 25 is installed with a vacuum breaking silencer component 6, and the left and right sides of the pump housing 12 are relatively provided with an air pressure reducing valve 24 and an air pressure reducing valve 137, and the left and right sides of the gear pump housing 9 are relatively provided with a quick connector 28, and the top of the gear pump housing 9 is connected with a quick connector 23, and the rear end of the sealing pump housing 19 is connected to the oil window 30, and the upper and lower sides of the oil window 30 are relatively provided with sealing plugs 31, and the upper and lower sides of the sealing pump housing 19 are embedded with sealing plugs 32.

[0039] In the embodiment, the surface of the pump housing 8 is provided with an annular channel, and the surface of the pump housing 8 is evenly distributed with guide protrusions. By optimizing the cooling path, the double-row angular contact ball bearing 5 adopts a double-row angular contact ball bearing with a protective cover, the quick connector 28 is a PC10-02SUS quick connector, and the quick connector 2 33 is a PACK-MEPY10 quick connector.

[0040] In summary, when in use, the motor is connected to the main screw 1, and the main screw 1 is driven by the motor. The main screw 1 and the auxiliary screw 2 are meshed and driven by the synchronous gear 13, so that the main screw 1 drives the auxiliary screw 2 to transmit, and the two screws rotate in opposite directions at high speed to realize air suction and exhaust. The gas enters from the blowing flange 25 and is discharged from the exhaust flange 24;

[0041] The end profiles of the main screw 1 and the auxiliary screw 2 adopt a water drop profile to form a completely sealed screw end profile, ensuring that the pump body has no leakage during operation, improving work efficiency and extending service life. The unique sealing structure not only enhances the sealing performance, but also greatly reduces maintenance costs. The optimized design of the screw end profile achieves higher processing accuracy and matching through precise processing technology, ensuring that a stable sealing effect can be maintained under high speed and high load conditions, minimizing friction loss and energy consumption. Mechanical seals 1 3 and 2 4 are provided on the front and rear shafts of the main screw 1 and the auxiliary screw 2 to provide higher wear resistance and corrosion resistance. The double sealing design combined with high-performance sealing materials greatly improves the stability and reliability of the equipment, ensuring that an excellent sealing effect can be maintained under long-term high-load operation. The new mechanical seal also has a self-adjusting function, which can automatically adjust the sealing clamping force according to the operating conditions, further improving the sealing performance and service life;

[0042] And the circulating cooling coolant is injected into the water jacket pump housing 17 and the pump housing 8 through the cooling flange 27, so that the coolant flows through the annular channel provided on the surface of the pump housing 8, and finally the coolant is discharged and cooled through the cooling flange 27 at the bottom of the water jacket pump housing 17, and then the coolant is re-injected, and the cycle is repeated in this way to effectively control the internal temperature of the equipment. The heat exchange technology and high-efficiency coolant are used to enable the heat to be quickly transferred from the key components to prevent the occurrence of overheating, and the vacuum pump can be ensured to operate stably and efficiently regardless of high or low temperature environments;

[0043] In addition, the top and bottom and left and right sides of the gear pump housing 9 are provided with purge ports, the purge ports at the top and bottom are connected to quick connectors 2 33, and the purge ports on the left and right sides are connected to quick connectors 1 28. Nitrogen is transported through the nitrogen purge exhaust pipe 26 and enters the pump housing 8 to purge the main screw 1 and the auxiliary screw 2, and is discharged through the purge ports on the quick connectors 2 33 and the quick connectors 1 28. By optimizing the purge path and designing the purge ports evenly distributed, an all-round, dead-angle-free purge effect is achieved, further improving the safety and durability of the equipment, and being able to minimize the oxygen content in the pump while ensuring the performance of the vacuum pump, thereby preventing oxidation reactions and corrosion.

[0044] The inner wall of the water jacket pump housing 17 is covered with a sound insulation pad, and the rear end of the pump housing 8 is provided with a strip-shaped inner groove to form a noise elimination chamber, which can effectively absorb and isolate the noise source, provide the operator with a quieter and more comfortable working environment, and help improve work efficiency and operating experience.

[0045] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. Dry variable lead twin screw vacuum pump, characterized by: It comprises a main screw (1), a secondary screw (2), a double-row angular contact ball bearing (5), a vacuum breaking and muffler assembly (6), a pump housing (8), a mechanical thrust cover (10), a synchronous gear (13), a gear mounting cone sleeve (14), a second round nut (16), a first water jacket pump housing (17), a second water jacket pump housing (20), a nitrogen purge exhaust pipe (26), and a cooling flange (27); The front shaft and rear shaft of the main screw (1) are respectively provided with a mechanical seal ring 1 (3) and a mechanical seal ring 2 (4); the front shaft and rear shaft of the auxiliary screw (2) are respectively provided with a mechanical seal ring 1 (3) and a mechanical seal ring 2 (4); a mechanical thrust cover (10) is installed at the rear end of the mechanical seal ring 2 (4); a double-row angular contact ball bearing (5) is connected to the rear end of the mechanical thrust cover (10); the mechanical thrust cover (10) is locked and fixed to the inner side of the sealing pump housing 2 (19) by a hexagon socket head screw 1 (11); a round nut 1 (7) is provided at the rear end of the double-row angular contact ball bearing (5); The main screw (1) and the auxiliary screw (2) are both placed inside the pump housing (8); the pump housing (8) is locked and fixed to the rear end of the gear pump housing (9) by means of a hexagon socket head screw (36); the gear pump housing (9) is locked and fixed to the rear end of the pump housing (12) by means of a hexagon socket head screw (36); the outer side of the pump housing (8) is wrapped with a water jacket pump housing (17); a plugging pump housing (18) is installed at the rear end of the water jacket pump housing (17); a plugging pump housing (19) is fixed to the rear end of the plugging pump housing (18); a water jacket pump housing (20) is installed at the front end of the pump housing (12); and an oil cover (22) is provided on the top of the pump housing (12); The top of the pump housing (8) is locked and fixed to the blowing flange (25) by using hexagon socket head screw four (23), and the water jacket pump housing (17) is locked and fixed to the bottom of the water jacket sealing gasket (29) by using hexagon socket head screw three (21). The top of the water jacket sealing gasket (29) is provided with a cooling flange (27), the bottom of the gear pump housing (9) is connected to an exhaust flange (24), and the middle of the blowing flange (25) is connected to a nitrogen purge exhaust pipe (26).

2. The dry variable lead twin-screw vacuum pump according to claim 1, characterized in that: The main screw (1) and the auxiliary screw (2) are arranged parallel to each other, and the screw end profiles of the main screw (1) and the auxiliary screw (2) are water drop profiles, the screw end of the main screw (1) and the screw end of the auxiliary screw (2) are in contact with each other, and a sealing ring (35) is arranged at the front end of the second mechanical seal ring (4).

3. The dry variable lead twin-screw vacuum pump according to claim 1, characterized in that: There are two groups of synchronous gears (13) in total, and the synchronous gears (13) are respectively arranged on the front shaft of the main screw (1) and the front shaft of the auxiliary screw (2), and the two groups of synchronous gears (13) are meshed with each other.

4. The dry variable lead twin-screw vacuum pump according to claim 4, characterized in that: The front end of the synchronous gear (13) is connected to the gear mounting cone sleeve (14) by means of two hexagon socket head screws (15), and the front end of the gear mounting cone sleeve (14) is provided with two round nuts (16).

5. The dry variable lead twin-screw vacuum pump according to claim 1, characterized in that: A vacuum breaking silencer assembly (6) is installed on the top of the blowing flange (25), and an air pressure reducing valve 2 (34) and an air pressure reducing valve 1 (37) are arranged on the left and right sides of the pump housing 3 (12) respectively.

6. The dry variable lead twin-screw vacuum pump according to claim 1, characterized in that: The left and right sides of the gear pump housing (9) are provided with quick connectors 1 (28) opposite to each other, the top of the gear pump housing (9) is connected with quick connector 2 (33), the rear end of the sealing pump housing 2 (19) is connected with an oil window (30), the upper and lower sides of the oil window (30) are provided with sealing plugs 1 (31) opposite to each other, and the upper and lower sides of the sealing pump housing 2 (19) are both embedded with sealing plugs 2 (32).

7. The dry variable lead twin-screw vacuum pump according to claim 1, characterized in that: The rear end of the pump housing (8) is provided with a strip-shaped inner groove, the surface of the pump housing (8) is provided with an annular channel, and the surface of the pump housing (8) is evenly distributed with flow-guiding protrusions.

8. The dry variable lead twin-screw vacuum pump according to claim 1, characterized in that: The gear pump housing (9) is provided with purge ports at the top and bottom and at both sides. The purge ports at the top and bottom are connected to quick connector 2 (33), while the purge ports at the left and right sides are connected to quick connector 1 (28).

9. The dry variable lead twin-screw vacuum pump according to claim 1, characterized in that: The inner wall of the water jacket pump housing (17) is covered with a sound insulation pad.

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