CN206801876U - A kind of Roots vacuum pump packing structure - Google Patents

Abstract

The utility model relates to a sealing structure of a Roots vacuum pump. The part inserted into the inner hole of the end cover (3) on the main shaft (2) is covered with a spiral bushing (4), and the spiral bushing (4) is covered with a sealing lining. sleeve (5), the sealing bush (5) is provided with an annular groove (5.1) on the outer ring surface of the end facing the fuel tank cap (10), and a set of oil deflectors (6) set on the One side of the sealing bush (5) is provided with a slot (6.1), and the groove wall of the above-mentioned annular groove (5.1) is embedded in the slot (6.1); the hole wall of the inner hole of the end cover (3) An oil return groove (3.1) is arranged on the top, and one end of the oil return groove (3.1) is connected to the annular groove (5.1), and the other end is connected to the cavity of the fuel tank cover (10). The utility model relates to a sealing structure of a Roots vacuum pump, which is simple, reliable, durable, low in cost and low in power consumption.

Description

A Roots vacuum pump sealing structure

technical field

The utility model relates to a sealing structure, in particular to a sealing structure applied to a Roots vacuum pump.

Background technique

At present, whether it is a Roots vacuum pump or other transmission machinery, the leakage and reliability of its dynamic seal have always been the focus of research; and as people's requirements for the reliability of vacuum pumps increase, it is necessary to find a simple, reliable and practical The sealing structure is the direction that vacuum pump manufacturers have been exploring.

Moreover, since the birth of the 1940s, the application of Roots vacuum pumps has become more and more extensive. At the same time, the research on the dynamic sealing of Roots vacuum pumps has not stopped, especially in the past two decades. With the application of technology, the sealing requirements of Roots vacuum pump are becoming more and more stringent. There are more and more types of gases delivered by Roots vacuum pumps, and the seal of Roots vacuum pumps must meet the needs of various special working conditions;

However, the main shaft seal of the conventional Roots vacuum pump generally adopts a single seal structure, so the defects of oil leakage and lubricating oil contamination will occur when used in harsh environments; Sealing and labyrinth composite sealing have been developed all the way, but the problem of sealing reliability of vacuum pumps has not been completely solved;

Specifically, piston ring seals, lip oil seals, mechanical seals, and labyrinth composite seals must rely on fluid liquid cooling and lubrication to maintain the normal use of the seals, so dry seals cannot be achieved. Moreover, there is friction between the seals, which is easy to wear, easy to generate heat, and consumes a lot of power. The most important thing is that two-way sealing cannot be realized. Once the pumped medium contains non-gas materials such as dust and liquid, the above-mentioned sealing structures will be in place. Failure in a short period of time will affect the normal use of the Roots vacuum pump.

Contents of the invention

The purpose of the utility model is to overcome the above disadvantages and provide a simple, reliable, durable, low cost and low power consumption Roots vacuum pump sealing structure.

The purpose of this utility model is achieved in that:

A Roots vacuum pump sealing structure, the structure includes a pump body, a main shaft is pierced through the end covers on both sides of the pump body, and an oil tank cover is fixed on the end cover; the above-mentioned main shaft is located at the end of the oil tank cover The transmission gear is set on the upper sleeve; the part inserted into the inner hole of the end cover on the main shaft is set on a spiral bushing, and a sealing bush is set on the spiral bushing, and the sealing bush faces the outer ring of one end of the fuel tank cap There is an annular groove on the surface, and a set of oil baffle plate set on the main shaft is provided with a slot on the side facing the sealing bush, and the groove wall of the above-mentioned annular groove is embedded in the slot; the inner hole of the end cover An oil return groove is arranged on the wall of the hole, and one end of the oil return groove is connected to the annular groove, and the other end is connected to the cavity of the fuel tank cap.

The utility model relates to a sealing structure of a Roots vacuum pump. The outer diameter of the oil retaining plate is not in contact with the inner hole of the end cover and a certain gap is maintained.

The utility model relates to a sealing structure of a Roots vacuum pump, wherein the sealing bush and the spiral shaft sleeve do not contact and maintain a certain gap.

The utility model relates to a sealing structure of a Roots vacuum pump. A bearing is set on the main shaft, and the bearing is in contact with the inner hole wall of the end cover, and the bearing cover set on the main shaft is pressed on the end cover.

Compared with the prior art, the beneficial effects of the utility model are:

The spiral seal adopted by the utility model has simple structure and high practicability, and the general numerical control processing equipment can meet its processing accuracy requirements, and controlling the matching gap between each part is the key to determine its sealing effect, so it can be well Satisfy the sealing effect; at the same time, the screw dry seal has the advantages of low manufacturing cost, easy installation, good reliability, no pollution, and long service life; after the Roots vacuum pump adopts the screw seal, it can completely isolate the lubricating oil from entering the vacuum pump body, thereby It avoids the oil pollution of the lubricating oil to the pumped gas, and also avoids the pollution of the pumped gas to the lubricating oil of the Roots vacuum pump; in addition, the screw seal has no friction and almost no heat, which will greatly improve the service life of the Roots vacuum pump. effect;

When the utility model is working, when the lubricating oil enters the position of the oil retaining plate, the lubricating oil is thrown away from the inner hole wall of the end cover and the annular groove of the sealing bush through the high-speed rotation of the oil retaining plate, and enters the annular groove. The lubricating oil falls into the oil return groove at the bottom of the inner hole of the end cap by gravity and finally flows back into the oil tank, which can completely block the lubricating oil from entering the pump body and prevent the lubricating oil from polluting the pumped gas in the pump body;

At the same time, when the main shaft of the vacuum pump rotates at high speed, it drives the helical sleeve to rotate together at high speed. The high-speed rotating helical sleeve will generate a reverse thrust cyclone, which can prevent harmful gas or dust or liquid medium in the pump body from entering the lubricating oil tank. Lubricating oil produces destructive effects; compared with traditional labyrinth seals, mechanical seals, and lip seals, this bidirectional seal structure has many advantages such as simple structure, good reliability, low manufacturing cost, and long service life.

Description of drawings

Fig. 1 is a structural schematic diagram of a Roots vacuum pump sealing structure of the present invention.

Fig. 2 is a partially enlarged view of a sealing structure of a Roots vacuum pump of the present invention.

in:

Pump body 1, main shaft 2, end cover 3, screw bushing 4, sealing bush 5, oil deflector 6, bearing 7, bearing gland 8, transmission gear 9, fuel tank cover 10;

Oil return tank 3.1;

Annular groove 5.1;

Socket 6.1.

detailed description

Referring to Fig. 1 and Fig. 2, the utility model relates to a Roots vacuum pump sealing structure, the structure includes a pump body 1, and the main shaft 2 is pierced through the end covers 3 on both sides of the pump body 1, and the end caps The fuel tank cover 10 is fixed on the cover 3; the transmission gear 9 is set on the end of the above-mentioned main shaft 2 located in the fuel tank cover 10;

The part of the main shaft 2 inserted into the inner hole of the end cover 3 is covered with a spiral bushing 4 (the spiral bushing 4 is a bushing structure with a spiral groove line on the outer ring surface of the bushing), and the spiral bushing 4 The upper sleeve is equipped with a sealing bush 5, and the outer ring surface of the end of the sealing bush 5 facing the fuel tank cover 10 is provided with an annular groove 5.1, and a set of oil deflectors 6 on the main shaft 2 faces one side of the sealing bush 5 There is an embedded groove 6.1 on the top, and the groove wall of the above-mentioned annular groove 5.1 is embedded in the embedded groove 6.1; the outer diameter of the oil deflector 6 does not contact the inner hole of the end cover 3 and maintains a certain gap, so that the sealing bush 5 is fastened in the end cover 3 of the vacuum pump, and the outer ring of one end of the sealing bush 5 has an annular groove 5.1, which is engaged with the oil retaining plate 6 with a certain gap to form a three-dimensional labyrinth sealing structure;

The hole wall of the inner hole of the end cover 3 is provided with an oil return groove 3.1, and one end of the oil return groove 3.1 is connected to the annular groove 5.1, and the other end is connected to the cavity of the fuel tank cover 10; the main shaft 2 is covered with a bearing 7 , and the bearing 7 is in contact with the inner hole wall of the end cover 3, and the bearing gland 8 set on the main shaft 2 is pressed on the end cover 3;

When in use, when the main shaft 2 rotates, it drives the transmission gear 9 to rotate synchronously, the lubricating oil in the fuel tank cover 10 is splashed by the transmission gear 9 and enters the bearing 7 in the end cover 3, and the oil retaining plate 6 throws off the lubricating oil entering the bearing 7. To the inner hole of the end cover 3 and the oil return groove 3.1 at one end of the sealing bush 5 arranged in the end cover 3, the lubricating oil finally flows back into the fuel tank cap 10 through the oil return groove 3.1, which can prevent the lubricating oil in the fuel tank cap 10 The oil enters the pump body 1; at the same time, when the screw sleeve 4 rotates, it will generate a reverse thrust facing the pump body 1. This reverse thrust can prevent the medium in the pump body 1 from entering the oil tank cover 10; the above seal can prevent the lubricating oil It interferes with the mutual pollution of the pumped gas, which has a good effect on the pumped medium and the service life of the vacuum pump;

In addition: it should be noted that the above specific implementation is only an optimization solution of this patent, and any changes or improvements made by those skilled in the art based on the above ideas are within the scope of protection of this patent.

Claims (4)

1. A Roots vacuum pump sealing structure, the structure includes a pump body (1), the end cover (3) on both sides of the pump body (1) is pierced with a main shaft (2), and the end cover ( 3) The fuel tank cover (10) is fixed on the top; the transmission gear (9) is set on the end of the above-mentioned main shaft (2) located in the fuel tank cover (10); its features are: The part of the main shaft (2) inserted into the inner hole of the end cover (3) is overlaid with a spiral sleeve (4), and the helical sleeve (4) is overlaid with a sealing bush (5). There is an annular groove (5.1) on the outer ring surface of the end of the sleeve (5) facing the fuel tank cover (10), and a set of oil deflectors (6) on the main shaft (2) faces the side of the sealing bush (5) An embedding groove (6.1) is arranged on the top, and the groove wall of the above-mentioned annular groove (5.1) is embedded in the embedding groove (6.1); an oil return groove (3.1) is arranged on the hole wall of the inner hole of the end cover (3), And one end of the oil return groove (3.1) is connected to the annular groove (5.1), and the other end is connected to the cavity of the fuel tank cap (10). 2 . The sealing structure of a Roots vacuum pump according to claim 1 , characterized in that: the outer diameter of the oil deflector ( 6 ) is not in contact with the inner hole of the end cover ( 3 ) and a gap is maintained. 3 . The sealing structure of a Roots vacuum pump according to claim 1 , characterized in that: the sealing bush ( 5 ) is not in contact with the screw sleeve ( 4 ) and a gap is maintained. 4 . 4. A Roots vacuum pump sealing structure according to claim 1, characterized in that: the main shaft (2) is overlaid with a bearing (7), and the bearing (7) is in contact with the inner hole wall of the end cover (3) contact, the bearing cover (8) set on the main shaft (2) is pressed onto the end cover (3).