A double-helix dry screw vacuum pump

Abstract

The present invention relates to a double-helix dry screw vacuum pump, comprising a cylinder and a vacuum pump body, wherein the vacuum pump body is fixedly arranged inside the cylinder, a rotor and a gas channel are arranged inside the vacuum pump body, the rotor comprises an active rotor and a passive rotor, the active rotor is fixedly connected above the passive rotor, the rotor comprises a rotating shaft rod and a plurality of teeth, the teeth are embedded in the outer surface of the rotating shaft rod and fixedly connected, the plurality of teeth are arranged in the inner cavity of the vacuum pump body, the rotating shaft rod passes through the vacuum pump body, the gas channel is fixedly arranged in the gap between the two sides of the rotor and the vacuum pump body, the two ends of the vacuum pump body are respectively provided with an air intake port and an exhaust port, the exhaust port is fixedly provided with an exhaust channel outside the vacuum pump body, the exhaust channel passes through the bottom of the cylinder, the two sides of the cylinder are respectively provided with a front shell and a rear shell by buckles, the structure is compact, the pumping speed is large, and the vacuum degree is high.

Description

Technical Field

[0001] The invention belongs to the technical field of screw vacuum pumps, and in particular relates to a double-helix dry screw vacuum pump. Background Art

[0002] In 1905, German Wolfgang Gade invented the oil-sealed rotary vane pump. Since then, various vacuum pumps using oil as working fluid, lubricant and sealing fluid have been popularized rapidly and dominated the vacuum equipment market for nearly a hundred years. Various forms of oil vacuum pumps inevitably discharge a large amount of oil pollution along with the discharged gas during operation, which seriously pollutes the environment. With the development of science and technology, many oil-free vacuum pumps have developed rapidly. From the evolution trend of the vacuum pump market in the 21st century, based on the research on the meshing characteristics of the profile, the deformation of the rotor under stress and the expansion under heat, new high-efficiency profiles are created to ensure that the profile processing is simple, the sealing volume between the teeth is large, the leakage triangle is small, the pumping speed is large, and the pumping efficiency is high. The progress of dry pumps is better than that of molecular pumps. Relatively slow. Although the existing dry screw vacuum pump has the advantages of high reliability, easy operation and maintenance, good power balance, strong adaptability, multi-phase mixed transmission, and no coughing and vibration, its main disadvantage is that the tooth surface of the screw rotor is a spatial curved surface, which requires the use of special tools and special machine tools. The manufacturing process is complicated and requires a high degree of sealing for each working chamber such as the cylinder. Therefore, the processing accuracy is very high and the cost is high. This brings many difficulties to practical applications and is not easy to promote and utilize. Because the dry screw vacuum pump relies on the gap to seal the gas, the dry screw vacuum pump generally has superior performance only when the volume flow rate is greater than 0.2 square meters / minute. Therefore, the dry screw vacuum pump cannot be used in micro occasions. For this reason, we propose a double-helix dry screw vacuum pump. Summary of the invention

[0003] In order to solve the above technical problems, the present invention provides a double-helix dry screw vacuum pump.

[0004] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0005] A double-helix dry screw vacuum pump comprises a cylinder and a vacuum pump body, wherein the vacuum pump body is fixedly arranged inside the cylinder, wherein a rotor and a gas passage are arranged inside the vacuum pump body, wherein the rotor comprises an active rotor and a passive rotor, wherein the active rotor is fixedly connected above the passive rotor, wherein the rotor comprises a rotating shaft rod and a plurality of teeth, wherein the teeth are embedded in the outer surface of the rotating shaft rod and fixedly connected, wherein the plurality of teeth are arranged in the inner cavity of the vacuum pump body, wherein the rotating shaft rod penetrates the vacuum pump body, wherein the gas passage is fixedly arranged in the gap between the two sides of the rotor and the vacuum pump body, wherein the Bearings are fixedly connected and arranged around the rotating shaft rod on the outside of the vacuum pump body, oil tanks are fixedly arranged near the bearings on both sides of the cylinder inner cavity, and a number of shaft seals are arranged at the fixed connection between the bearing and the rotating shaft rod. Suction holes and exhaust holes are respectively opened at both ends of the vacuum pump body, and an exhaust channel is fixedly arranged on the outside of the vacuum pump body of the exhaust hole, and the exhaust channel runs through the bottom of the cylinder. A cooling water ring is fixedly arranged on the outside of the cylinder, and an oil seal is arranged at the fixed connection between the active rotor and the outside of the cylinder. A front outer shell and a rear outer shell are respectively arranged on both sides of the cylinder through buckles.

[0006] Furthermore, the cylinder is in an ∞ shape.

[0007] Furthermore, the active rotor and the passive rotor are both spiral-shaped, parallel to each other and in opposite directions, and the plurality of teeth are meshed with each other.

[0008] Furthermore, the air intake opening and the air exhaust opening are of the same shape and size.

[0009] Furthermore, there are two cooling water rings, which are symmetrically arranged on both sides of the cylinder.

[0010] Furthermore, an air suction end surface is arranged at one end of the rotor close to the air suction hole.

[0011] Furthermore, an exhaust end surface is provided at one end of the rotor near the exhaust port.

[0012] Furthermore, a synchronous gear is provided on the rotating shaft rod in the passive rotor near the rear housing, and the synchronous gear is fixedly connected to the rotating shaft rod on the right side of the bearing.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] In this device, the rotor is set to increase the sealing volume between teeth, reduce leakage, increase pumping speed and improve pumping efficiency;

[0015] In this device, the gas channel, the air intake port and the air exhaust port are coordinated to make the fluid in the device flow evenly in the pump chamber, with good dynamic balance. The invention has a scientific and reasonable structure and is safe and convenient to use. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention.

[0017] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0018] Figure 2 It is a schematic diagram of the rotor structure of the present invention;

[0019] Figure 3 It is a schematic diagram of the suction end surface structure of the present invention;

[0020] Figure 4 It is a schematic diagram of the exhaust end surface structure of the present invention;

[0021] In the figure: 1-cylinder, 2-vacuum pump body, 3-rotor, 4-active rotor, 5-passive rotor, 6-rotating shaft, 7-gear, 8-bearing, 9-oil tank, 10-intake hole, 11-exhaust hole, 12-gas channel, 13-shaft seal, 14-oil seal, 15-intake end face, 16-exhaust end face, 17-front housing, 18-rear housing, 19-synchronous gear, 20-exhaust channel, 21-cooling water ring. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0023] See also Figure 1 , Figure 2 , Figure 3 and Figure 4 , the present invention provides a technical solution:

[0024] A double-helix dry screw vacuum pump comprises a cylinder 1 and a vacuum pump body 2, wherein the vacuum pump body 2 is fixedly arranged inside the cylinder 1, a rotor 3 and a gas passage 12 are arranged inside the vacuum pump body 2, the rotor 3 comprises an active rotor 4 and a passive rotor 5, the active rotor 4 is fixedly connected above the passive rotor 5, the rotor 3 comprises a rotating shaft rod 6 and a plurality of teeth 7, the teeth 7 are embedded in the outer surface of the rotating shaft rod 6 and fixedly connected, the plurality of teeth 7 are arranged in the inner cavity of the vacuum pump body 2, the rotating shaft rod 6 passes through the vacuum pump body 2, the gas passage 12 is fixedly arranged in the gap between the two sides of the rotor 3 and the vacuum pump body 2, the outside of the vacuum pump body 2 is fixedly connected with a bearing 8 around the rotating shaft rod 6, and the inner cavity of the cylinder 1 is near the bearing 8 on both sides. An oil tank 9 is fixedly arranged, and a plurality of shaft seals 13 are arranged at the fixed connection between the bearing 8 and the rotating shaft rod 6. Suction holes 10 and exhaust holes 11 are respectively opened at both ends of the vacuum pump body 2. The exhaust hole 11 is fixedly provided with an exhaust channel 20 outside the vacuum pump body 2. The exhaust channel 20 runs through the bottom of the cylinder 1. A cooling water ring 21 is fixedly arranged outside the cylinder 1. An oil seal 14 is arranged at the fixed connection between the active rotor 4 and the outside of the cylinder 1. A front shell 17 and a rear shell 18 are respectively arranged on both sides of the cylinder 1 through buckles. This device has few parts, good power balance, compact structure, high pumping speed, high vacuum degree, can be directly discharged into the atmosphere, has no friction between working parts, long service life, strong self-priming ability, and no easily damaged parts.

[0025] In this embodiment, the cylinder 1 is in the shape of ∞.

[0026] In this embodiment, the active rotor 4 and the passive rotor 5 are both spiral-shaped. When the two rotors are meshed with each other, X2=X2(t,ψ1(t)), Y2=Y2(t,ψ1(t)), f(t,ψ1)=0, and the two are parallel to each other and in opposite directions. A number of meshing teeth 7 are meshed with each other, and the spiral angle between the meshing teeth 7 and the rotating shaft rod 6 is: T=2πRcotβ. The close dynamic performance between the rotors obtains a higher quality vacuum, and there is a gap between the tooth surfaces, which can withstand liquid impact and can also transport other liquids, gases, etc.

[0027] In this embodiment, the suction port 10 and the exhaust port 11 have the same shape and size, and there is no surge, so continuous exhaust can be easily achieved. The displacement of the exhaust port 11 is: F=2πR²-f.

[0028] In this embodiment, there are two cooling water rings 21, which are symmetrically arranged on both sides of the outside of the cylinder 1 to ensure that the device is heated evenly during operation.

[0029] In this embodiment, an air suction end surface 15 is provided at one end of the rotor 3 close to the air suction port 10 .

[0030] In this embodiment, an exhaust end surface 16 is provided at one end of the rotor 3 close to the exhaust port 11 .

[0031] In this embodiment, the rotating shaft rod 6 in the passive rotor 5 is provided with a synchronous gear 19 near the rear housing 18 , and the synchronous gear 19 is fixedly connected to the rotating shaft rod 6 on the right side of the bearing 8 .

[0032] The working principle and use process of the present invention:

[0033] When a double-helix dry screw vacuum pump is working, the suction process is as follows: a pair of mutually meshing spiral rotors 3 are arranged in parallel in an ∞-shaped cylinder 1, wherein the two meshing teeth 7 on the active rotor 4 and the passive rotor 5 are of the same shape and rotate in opposite directions, the active rotor 4 is rotated counterclockwise by the rotating shaft rod 6, driving the meshing teeth 7 on the active rotor 4 to rotate counterclockwise, and the rotating shaft rod 6 of the passive rotor 5 is driven by the meshing teeth 7 to rotate clockwise, and the meshing teeth 7 on the passive rotor 5 rotate synchronously in the clockwise direction, and a suction port 10 and an exhaust port 11 of a certain shape and the same size are respectively opened at both ends of the vacuum pump body 2, and the meshing teeth 7 of the active rotor 4 and the passive rotor 5 near the suction port 10 are completely meshed, and are about to be together with the suction port 10, as the rotor 3 starts to rotate, due to one end of the meshing teeth 7 gradually The inter-tooth volume is formed when the meshing is disengaged, and a certain vacuum is formed inside the vacuum pump body 2. This inter-tooth volume is only connected to the suction port 10. Therefore, the gas flows into the gas channel 12 through the suction port 10 under the action of the pressure difference. As the inter-tooth volume continues to expand and remains connected to the suction port 10, when the inter-tooth volume reaches the maximum value, as the rotor 3 rotates, the inter-tooth volume will no longer increase, and the inter-tooth volume is disconnected from the suction port 10 at this position, that is, the suction process ends; the inter-tooth volume is connected to the exhaust port 10, that is, the exhaust process begins, as the inter-tooth volume continues to shrink, the gas with exhaust pressure is gradually discharged through the exhaust port 11 along the gas channel 12, and the gas is finally completely discharged from the outside of the cylinder 1 along the exhaust port 20, and the closed inter-tooth volume evolves to zero. This process is the exhaust process.

[0034] The above are preferred implementation modes of the present invention. Those skilled in the art to which the present invention belongs can also change and modify the above implementation modes. Therefore, the present invention is not limited to the above specific implementation modes. Any obvious improvements, substitutions or modifications made by those skilled in the art on the basis of the present invention belong to the protection scope of the present invention.

Claims

1. A double-helix dry screw vacuum pump, comprising a cylinder (1) and a vacuum pump body (2), characterized in that: A vacuum pump body (2) is fixedly arranged inside the cylinder (1), and a rotor (3) and a gas passage (12) are arranged inside the vacuum pump body (2). The rotor (3) comprises an active rotor (4) and a passive rotor (5), and the active rotor (4) is fixedly connected above the passive rotor (5). The rotor (3) comprises a rotating shaft rod (6) and a plurality of teeth (7), and the teeth (7) are embedded in the outer surface of the rotating shaft rod (6) and fixedly connected. The plurality of teeth (7) are arranged in the inner cavity of the vacuum pump body (2), and the rotating shaft rod (6) passes through the vacuum pump body (2). The gas passage (12) is fixedly arranged in the gap between the two sides of the rotor (3) and the vacuum pump body (2). The outside of the vacuum pump body (2) is fixed around the rotating shaft rod (6). A bearing (8) is fixedly connected, an oil tank (9) is fixedly arranged near the bearing (8) on both sides of the inner cavity of the cylinder (1), a plurality of shaft seals (13) are arranged at the fixed connection between the bearing (8) and the rotating shaft rod (6), an air intake port (10) and an air discharge port (11) are respectively opened at both ends of the vacuum pump body (2), an air discharge channel (20) is fixedly arranged on the outside of the vacuum pump body (2), the air discharge port (11) runs through the bottom of the cylinder (1), a cooling water ring (21) is fixedly arranged on the outside of the cylinder (1), an oil seal (14) is arranged at the fixed connection between the active rotor (4) and the outside of the cylinder (1), and a front shell (17) and a rear shell (18) are respectively arranged on both sides of the cylinder (1) by buckles; The cylinder (1) is in the shape of ∞; The active rotor (4) and the passive rotor (5) are both spiral-shaped, parallel to each other and in opposite directions, and the plurality of meshing teeth (7) mesh with each other.

2. The double-helix dry screw vacuum pump according to claim 1, characterized in that: The air intake opening (10) and the air exhaust opening (11) have the same shape and size.

3. The double-helix dry screw vacuum pump according to claim 1, characterized in that: The number of the cooling water rings (21) is two, which are symmetrically arranged on both sides of the outside of the cylinder (1).

4. The double-helix dry screw vacuum pump according to claim 1, characterized in that: An air suction end surface (15) is provided at one end of the rotor (3) close to the air suction port (10).

5. The double-helix dry screw vacuum pump according to claim 1, characterized in that: An exhaust end surface (16) is provided at one end of the rotor (3) close to the exhaust port (11).

6. The double-helix dry screw vacuum pump according to claim 1, characterized in that: The rotating shaft rod (6) in the passive rotor (5) is provided with a synchronous gear (19) near the rear housing (18); the synchronous gear (19) is fixedly connected to the rotating shaft rod (6) on the right side of the bearing (8).

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