KR102207036B1 - Vacuum pump with suction structure of impeller-type balancing weight - Google Patents

Abstract

The present invention relates to a vacuum pump with a suction structure of an impeller type balancing weight, which satisfies a gas suction condition from an initial inlet through rotation-centrifugal force generated inside a guide bracket when variable wings forming a balancing weight are rotated with a screw rotor together while having a shape of a turbine wing, minimizes damage to the screw rotor caused by drilling of a balancing hole for identifying existing center of gravity and rotating without breaking balance of the center of gravity since the rotational center of gravity of the screw rotor is easily identified when eccentric arrangement of the variable wings are coupled and applied to the screw rotor, and balances a product of which rotational center of gravity relative to a rotor is impossible to be identified except the screw rotor so as to improve productivity related to the screw rotor.

Description

Vacuum pump with suction structure of impeller-type balancing weight

The present invention relates to a vacuum pump having a suction structure of an impeller-type balancing weight, and more particularly, a balancing weight on a driving shaft and a driven shaft of a screw rotor forming a pair in the vacuum pump to fit the rotational weight center. The present invention relates to a vacuum pump having a suction structure of an impeller type balancing weight that is installed to increase the amount of vacuum suction during the initial rotation of both screw rotors to realize efficient vacuum pumping and to improve the service life of the vacuum pump.

In recent years, the progress of vacuum technology is remarkably fast, and its application fields are also spreading to semiconductor deposition, electronics industry, metal chemistry, pharmaceuticals, and nuclear industry. In addition, there are many types of vacuum pumps that create a vacuum, such as a water ring type, an oil rotation type, a Roots type, an oil diffusion type, a physical adsorption type, and a chemical adsorption type, but can be largely divided into a wet type and a dry type.

For example, a vacuum pump in which a pair of screw rotors is applied to inhale and discharge gas is a device that removes gas molecules in an airtight container. Gas is sucked and compressed at a low pressure below atmospheric pressure and released into the atmosphere to reduce the degree of vacuum in the container. Raise. These vacuum pumps are largely classified into mechanical vacuum pumps and diffusion/ion pumps, each represented by dry and wet types.

Unlike the diffusion/ion pump of a wet type that uses oil or mercury to achieve high vacuum, the mechanical vacuum pump has a relatively low degree of vacuum, but a dry type that does not use oil, so its structure is relatively simple and has good durability.

In addition, since it shows a stable degree of vacuum, it is widely used in various industrial fields because the user can easily operate it and the cost to maintain it is low.

The vacuum pump to which the screw-type impeller is applied has an inlet and an outlet at the top and bottom of a housing having a compression space, and the inside of the vacuum pump has a drive shaft and a screw each provided with a screw so that gas can be compressed through the housing. It is composed of a drive means for transmitting power to the coaxial and the drive shaft to rotate the driven shaft interlocked.

Both ends of the drive shaft and the driven shaft are rotatably supported by bearings, and the drive means is composed of a motor provided on the drive shaft and gears that transmit the power of the drive shaft to the driven shaft, and a gas inlet pipe at the inlet and outlet port And gas discharge pipe is provided so that gas can be forcibly transferred.

When the motor provided on the drive shaft is driven, the conventional vacuum pump configured as described above rotates in a state where the drive shaft, the gear of the driven shaft meshed with the gear installed on the drive shaft, and the screw provided on the drive shaft and the driven shaft are rotated in a state where they are engaged with each other. Becomes lower than the external air pressure. Therefore, the gas flows into the compression space from the inlet, is compressed, and then discharges through the outlet.

However, in such a vacuum pump, both ends of the screw thread at the beginning of the inlet close to the inlet have a thin thickness on one side and a thick thickness on the other side, so that the weight is not balanced, resulting in a disturbed rotation center, and rotation is not smooth.

In addition, damage to the pump and the motor is caused due to durability problems during high-speed rotation.

Looking at the related source technology for solving the above, Korean Patent Registration No. 10-1320053 (Name: screw rotor and vacuum pump to which the screw rotor is applied, registration date: October 14, 2013, hereinafter'Patent Document 1') and Patent No. 10-1603140 (name: vacuum pump equipped with a screw rotor, registration date: March 08, 2016, hereinafter referred to as Patent Document 2) are disclosed.

The screw rotor of Patent Document 1 is a screw rotor 10 fixed and rotated on a rotating main shaft 3, as shown in FIG. 1, each having a plurality of threads 30 and screw grooves 31 formed therein. The first-stage screw 11 and the second-stage screw 12 are formed to form a vacuum, but the first-stage screw 11 and the second-stage screw 12 have the same outer diameter (D) and a valley diameter (d) It has and characterized in that it further comprises a balancing hole 20 formed in the thread to match the weight balance.

Patent Literature 2 is to solve the problem of the balancing hole of Patent Literature 1, and its configuration is the first and second main screw having blades having the same thread lead length on the main shaft 11 as shown in FIG. (12, 13) and the third, fourth, fifth main screw (14, 15, 16) having blades shorter than the first and second main screw (12, 13) and each having the same thread lead length are provided. The length of the thread lead between the screws 12, 13, 14, 15, 16 is configured to decrease from the fluid intake part (A) to the fluid discharge part (B), and the main screw (12, 13, 14, 15, A main screw rotor 10 composed of a main flank 17 provided in 16); First and second driven screws (22, 23) having blades having the same thread lead length on the driven shaft (21) and blades shorter than the first and second driven screws (22, 23) and having the same thread lead length respectively 3rd, 4th, 5th driven screws (24, 25, 26) are provided, and the thread lead length between each driven screw (22, 23, 24, 25, 26) is from the fluid intake (A) to the fluid discharge (B). ) Is configured to become smaller in the direction of the driven screw (22, 23, 24, 25, 26) of the driven screw (22, 23, 24, 25, 26) is provided with a driven screw rotor (20) consisting of a driven flank (27); is provided, the first, A plurality of main flank holes (18) and driven in the main flank (17) surface formed in the two main screws (12, 13) and the driven flank (27) formed in the first and second driven screws (22, 23), respectively. A flank hole 28 is provided, and the surface of the main flank 17 and the surface of the driven flank 27 are fitted.

The balancing hole 20 of Patent Document 1 and the flank holes 18 and 28 of Patent Document 2 must undergo a balancing process in order to align the center of gravity with the center of rotation after screw processing.

This processing method reduces the unbalanced weight with respect to the rotational center of gravity of the screw rotor by drilling on the outer diameter of the screw or the flank, which is a spiral part, so that the center of gravity is aligned with the rotation center.

This is a work that compensates for the unbalanced mass to increase the life of the machine and improve the performance of the machine by reducing the vibration of the rotating body, i.e., balancing work, a hole work on the outer diameter of the screw to align the unbalanced weight to the rotation center. At this time, as the number of holes increases and the depth of processing increases, damage to the skew rotor itself occurs, and as the number of such balancing holes increases, the vacuum efficiency decreases due to the characteristics of the vacuum pump. .

In addition, in addition to the unbalanced mass of the casting, a lot of weight exists on one side only in the form of a screw, and considerable work time is required to reduce this weight.

If the center of gravity of the screw does not coincide with the center of rotation, the center of mass of the rotating body is eccentric from the center of rotation, and an unbalanced mass exists, the rotating body is in an unbalanced state.

As the screw rotation speed increases, a greater unbalanced centrifugal force is generated by mass eccentricity, and this centrifugal force is transmitted to the bearing and support, causing structural vibration and noise, and at the same time, the compression force decreases, making vacuum pumping inefficient. It has been pointed out that the lifespan is shortened, and it takes a long time to manufacture and produce a vacuum pump.

The present invention was invented to solve the conventional problems as described above, and by simply mounting and using a balancing weight according to the rotational center of gravity on the drive shaft and the driven shaft of the screw rotor, the rotational weight of the screw rotor By minimizing the balancing hole processing work on the center, the appearance of the screw rotor is preserved, while the balancing weight is designed in the shape of a turbine blade to increase the amount of vacuum suction when rotating with the screw rotor to realize efficient vacuum pumping and the service life of the vacuum pump. It is an object to provide a vacuum pump having a suction structure of an impeller-type balancing weight that can significantly extend and improve the manufacturing productivity of the vacuum pump by minimizing the balancing work time for the rotational center of gravity of the screw rotor.

According to the present invention for achieving the above object, a screw rotor in which a screw portion is arranged in series on a drive shaft connected to the drive motor and a driven shaft connected to the drive shaft is guided and installed in the housing, and the housing is sealed at one side of the housing. A vacuum pump consisting of a structure in which the driving shaft and the driven shaft are rotated and supported by the cover support, and the gas is sucked from the inlet provided on the housing side at a low pressure below atmospheric pressure, compressed into a vacuum state, and released to the atmosphere through the outlet on the housing side. In,

Variable blades in the shape of a turbine-type blade having a difference in width and a difference in weight are formed radially outward of the shaft hole and the shaft hole guided to the drive shaft and the driven shaft, and which are smaller than the outer diameter of the screw part. Among the variable blades, a balancing weight having at least one fastening hole fixed to the drive shaft and the driven shaft with a fastening screw is formed between the variable blades and is coupled on the same axis of the drive shaft and the driven shaft of the screw rotor,

One side is a disc-shaped notched, divided and press-fit into the inner diameter end of the housing through which the drive shaft and the driven shaft are passed, and a support shaft portion through which the drive shaft and the driven shaft are supported is formed on the center thereof, and the balancing When the balancing weight is rotated while guiding the weight, a guide groove is provided from the inlet to induce gas intake, and a guide bracket provided with a plurality of fixing holes is combined on one side,

The cover support is a fastening member and is coupled and fixed to the fixing hole of the guide bracket and the housing, respectively.

The guide bracket to which the balancing weight is guided according to the present invention is coupled to the drive shaft and the driven shaft to protrude from the guide groove, and gas intake is induced from the inlet.

Gas passage grooves are respectively formed on the cut side of the guide bracket according to the present invention, and the guide brackets are coupled to each other in a form in which the gas passage grooves face each other.

The vacuum pump having the suction structure of the impeller-type balancing weight according to the present invention includes, first, the variable blades forming the balancing weight have a turbine blade shape, and the gas from the initial inlet is the rotational centrifugal force generated in the guide bracket when rotating together with the screw rotor. It satisfies the suction condition, and secondly, the deviation arrangement of the variable blades makes it easy to obtain the rotational center of gravity of the screw rotor when it is coupled to the screw rotor, so the screw rotor by drilling of the balancing hole to obtain the center of gravity as before. It rotates without breaking the balance of the rotation center while minimizing damage to the rotation center. Third, it is possible to balance products that are not capable of rotating center of gravity work on the rotating body other than the screw rotor, thereby improving product productivity related to the screw rotor. It works.

1 is a cross-sectional view showing a main part of a screw dry vacuum pump to which a screw rotor of the prior art is applied,
2 is a cross-sectional view showing the main part of a screw dry vacuum pump to which another conventional screw rotor is applied,
3 is a perspective view showing the appearance of a vacuum pump for explaining the present inventors impeller-type balancing weight,
4 is a perspective view showing the inside of the vacuum pump excluding the housing according to the present invention
5 is a perspective view showing an extract of the screw rotor, guide bracket, and cover support from FIG. 4;
6 is a cross-sectional view illustrating a state in which a balancing weight, a guide bracket, and a cover support are applied and installed to the screw rotor according to the present invention;
7 is a cross-sectional view showing a state in which a balancing weight, a guide bracket, and a cover support are installed in FIG. 6;
8 is an enlarged view showing a gas inhalation state in FIG. 7;
9 is a perspective view showing a state in which a balancing weight and a guide bracket are disposed inside by cutting a portion of the housing in FIG. 8;
10 is a cross-sectional view illustrating a gas inflow state according to the rotation of the balancing weight within the guide bracket according to the present invention;
Figure 11 (a) (b) (c) is a side view illustrating a state in which balancing weights are mounted at different angles on a screw rotor on a driven shaft and a drive shaft.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

Prior to this, terms or words used in the specification and claims should not be construed as being limited to their usual or dictionary meanings, and the inventors appropriately explain the concept of terms in order to explain their own invention in the best way. Based on the principle that it can be defined, it should be interpreted as a meaning and concept consistent with the technical idea of the present invention.

Accordingly, the embodiments described in the present specification and the configurations shown in the drawings are only the most preferred embodiments of the present invention, and do not represent all the technical ideas of the present invention, so at the time of application, these can be replaced. It should be understood that there may be various equivalents and variations.

The configuration of the vacuum pump 100 according to the present invention is as shown in FIGS. 3 to 10.

Screw rotors 10 and 20 in which screw units 10-1 and 10-2 are arranged in series on the drive shaft 12 connected to the drive motor M and the driven shaft 22 connected to the drive shaft It is guided in the housing 101, and at one side of the housing, the drive shaft and the driven shaft are rotatably supported by a cover support 110 that seals the housing, and an inlet port provided on the housing side at a low pressure below atmospheric pressure ( In the vacuum pump 100 configured to be suctioned from 102, compressed into a vacuum state, and discharged to the atmosphere through the outlet 103 at the housing side,

It is smaller than the outer diameter of the screw parts 10-1 and 10-2, and the difference in the suction flow rate of gas to the outside of the shaft hole 201 and the shaft hole 201 guided to the drive shaft 12 and the driven shaft 22 And turbine-type blade-shaped variable blades 202 having a weight deviation are formed in a radial arrangement with different widths, and a fastening screw to the drive shaft 12 and the driven shaft 22 between the variable blades among the variable blades 202 A balancing weight 200 having one or more fastening holes 203 fixed to (S) is coupled on the same axis of the drive shaft 12 and the driven shaft 22 of the screw rotors 10 and 20.

That is, the balancing weight 200 is installed on the drive shaft 12 and the driven shaft 22 of the screw rotors 10 and 20 close to the inlet 102, and is installed together with the guide bracket 300.

The guide bracket 300 is a pair of disks with one side cut out from the true circle and having a thickness, as shown in the attached FIGS. 4 and 5, the drive shaft 12 and the driven shaft 22 pass Each of the inner diameter end of the housing 101 to be divided and press-fit is installed.

In addition, a support shaft portion 301 through which the drive shaft 12 and the driven shaft 22 are supported is formed on the center, and an inlet 102 when the balancing weight rotates while guiding the balancing weight 200 on one side of the inner side to be press-fitted. ) Is provided with a guide groove 303 for inducing gas intake, and a plurality of fixing holes 304 are provided on one surface thereof.

The guide bracket 300 is coupled to the drive shaft 12 and the driven shaft 22 so as to protrude from the guide groove 303 to induce gas intake from the inlet 102 when the balancing weight 200 is rotated. will be.

On the other hand, gas passage grooves 302 are formed on the cut-out side of the guide bracket 300, respectively. The gas passage groove 302 is to generate the same suction force for each centrifugal suction force generated from the guide grooves of both guide brackets 300 when the balancing weight 200 guided to the guide groove 303 rotates.

The guide bracket 300 as described above has a structure in which the guide bracket 300 is coupled in a form in which the gas passage groove 302 faces and contacts, and is installed together with the housing and the cover support.

That is, the cover support 110 as a fastening member is coupled and fixed to the fixing hole 304 and the housing 101 of the guide bracket 300, respectively.

In the drawings, unexplained reference numeral B denotes a bearing provided on the cover support to support rotation of the drive shaft and the driven shaft, and reference numerals 10a and 20a denote balancing holes formed in the screw portions 10-1 and 10-2.

The operation according to the operation of the vacuum pump having the suction structure of the impeller-type balancing weight of the present invention configured as described above will be described as follows.

First, in the housing 101 of the vacuum pump 100, a pair of screw rotors 10 and 20, which are rotatably installed on both sides, are generally manufactured at both ends of the screw threads of the screw portions 10-1 and 10-2. Due to the difference in thickness, the weight due to rotation is not balanced, so the thickest screw parts (10-1) (10-2) process the balancing holes (10a, 20) around the outer circumference, but the number of balancing holes ( Process 10a) (20a) to provide a screw rotor close to the center of gravity of rotation.

A balancing weight 200 is mounted and fixed to the screw rotors 10 and 20 divided into the drive shaft 12 and the driven shaft 22, respectively, as shown in FIGS. 4 and 5.

The balancing weight 200 guides the shaft hole 201 to each corresponding shaft, makes it as close as possible to the end of the screw part, and then fastens and fixes the provided fastening screw (S) to the fastening hole 203 at two points, respectively, and a vacuum pump Before being installed in the housing 101 of the 100, it is set in a device that adjusts the center of gravity of rotation to check whether the center of gravity according to the rotation is correct.

That is, a method of rotating the balancing weight 200 on the drive shaft 12 or the driven shaft 22 by loosening the fastening screw again as much as the deviation of the rotation center of gravity with respect to the screw parts 10-1 and 10-2 occurs. Re-inspection is performed and the position is adjusted so that the rotational center of gravity of the screw rotors 10 and 20 is consistent.

In the same manner as described above, screw rotors 10 and 20 whose rotation center of gravity exactly fits the center are rotatably connected at both ends of the housing, and drive gear G1 is connected to the drive shaft 12, and the driven shaft 22 The driven gear (G2) is coupled to, and the drive shaft (12) is connected to the drive motor (M).

A balancing weight 200 is installed on the drive shaft 12 or driven shaft 22 on the opposite side of the screw rotors 10 and 20 as described above, and the end of the drive shaft 12 or driven shaft 22 is a guide bracket ( 300) through the shaft support portion 301.

Here, the guide bracket 300 is combined so that the outside is pressed into the inner diameter of the housing 101, but using a fastening member from the outside of the cover support 110, the fixing hole 304 and the housing 101 of the guide bracket By fastening to and fixing, the installation of the screw rotors 10 and 20 is completed. For reference, the drive shaft 12 or the driven shaft 22 guided to the cover support 110 is supported by a bearing B provided.

The balancing weight 200 installed on the drive shaft 12 or the driven shaft 22 of the screw rotors 10 and 20 is a guide groove part 303 of the guide bracket 300 as shown in FIGS. 7 to 9. ), and one side is installed to protrude to the outside of the guide groove by an interval (T), so when the occlusal rotation of the screw rotor is made by operating the driving motor (M), gas is introduced from the target device. In this case, the gas intake activates the gas intake earlier than the screw part by the rotation of the variable blades of the balancing weight.

As shown in FIG. 10, when the screw rotors 10 and 20 rotate through the inlet 102, the balancing weight 200 rotates within the guide bracket 300 to initially satisfy the gas intake condition. You will be able to. In particular, the gas passage groove 302 on the side of the guide bracket 300, which is abutted in a pair, is in a form of mutual communication, and when the screw rotors 10 and 20 are rotated from both sides, the gas is pumped with the same pressure to initially inhale the gas. It satisfies the satisfaction, and the pumping that occurs as the rotation of the screw rotor gradually increases can increase the vacuum compression efficiency.

Attached Figure 11 shows the balance weight 200 located at the end of the screw portion (10-1) (10-2) on the drive shaft 12 and the driven shaft 22, (a) (b) (c ) Shows the form in which the balance weight is mounted in accordance with the center of gravity of the screw rotors 10 and 20, which is the weight according to the position of the variable blades 202 each having a different width in one balancing weight 200 The center of gravity is in balance due to the deviation.

In addition, rotation of the balancing weight 200, each of which has a different wing angle as described above, increases the amount of gas inhaled together with the screw portions 10-1 and 10-2 to provide the target device-side vacuum compression condition. I can.

In the end, the balancing weight 200 according to the present invention has been described for the screw pump, but the center of gravity is set by varying the position of the balancing weight on the shaft for the center of gravity of any rotating body that inflows and transports gas as well as fluid. Since it is easy to find and balance the rotation of the rotating body, it is possible to solve the vibration and noise caused by the rotation center being disturbed due to the unbalanced. Especially, it can be applied to both the screw or various impeller shafts that require high-speed rotation. It provides the advantage of shortening the life of the pump and motor by solving the durability problem.

As described above, in the present invention, specific matters such as specific components, etc., and limited embodiments and drawings have been described, but this is provided only to help a more general understanding of the present invention, and the present invention is not limited to the above embodiments. , If a person of ordinary skill in the field to which the present invention belongs, various modifications and variations are possible from these descriptions.

Therefore, the spirit of the present invention is limited to the described embodiments and should not be defined, and all things that are equivalent or equivalent to the claims as well as the claims to be described later belong to the scope of the invention. .

10, 20: screw rotor 10a, 20a: ballast hole
10-1: 10-2: screw part 12: drive shaft
22: driven shaft 100: vacuum pump
101: housing 102: inlet
103: outlet 110: cover support
200: balance weight 201: shaft work
202: variable wing 203: fastening hole
300: guide bracket 301: support shaft
302: gas passage groove 303: guide groove
304: fixed hole B: bearing
M: drive motor S: fastening screw

Claims (3)

Screw rotors 10 and 20 in which screw units 10-1 and 10-2 are arranged in series on the drive shaft 12 connected to the drive motor M and the driven shaft 22 connected to the drive shaft It is guided in the housing 101, and at one side of the housing, the drive shaft and the driven shaft are rotatably supported by a cover support 110 that seals the housing, and an inlet port provided on the housing side at a low pressure below atmospheric pressure ( In the vacuum pump 100 configured to be suctioned from 102, compressed into a vacuum state, and discharged to the atmosphere through the outlet 103 at the housing side,
It is smaller than the outer diameter of the screw parts 10-1 and 10-2, and the difference in the suction flow rate of gas to the outside of the shaft hole 201 and the shaft hole 201 guided to the drive shaft 12 and the driven shaft 22 And turbine-type blade-shaped variable blades 202 having a weight deviation are formed in a radial arrangement with different widths, and a fastening screw to the drive shaft 12 and the driven shaft 22 between the variable blades among the variable blades 202 A balancing weight 200 having one or more fastening holes 203 fixed to (S) is coupled on the same axis of the drive shaft 12 and the driven shaft 22 of the screw rotors 10 and 20,
One side of the disc shape is cut off, the drive shaft 12 and the driven shaft 22 are divided into each of the inner diameter end of the housing 101 through which it passes, the drive shaft 12 and the driven shaft 22 A support shaft portion 301 through which) is supported is formed, and a guide groove portion 303 for guiding gas intake from the inlet 102 when the balancing weight is rotated while guiding the balancing weight 200 is provided on one side thereof. It is coupled to the drive shaft 12 and the driven shaft 22 so as to protrude from 303 to induce gas intake from the inlet 102, and a guide bracket 300 having a plurality of fixing holes 304 provided on one side thereof is coupled. , Gas passage grooves 302 are respectively formed on the cut side of the guide bracket 300, and the guide bracket 300 is coupled in a form in which the gas passage grooves 302 face each other and contact,
The cover support 110 is a vacuum pump having a suction structure of an impeller type balancing weight, characterized in that it is coupled and fixed to a fixing hole of a guide bracket and a housing as a fastening member. delete delete

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