JP3099516B2 - Vacuum pump - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum pump used in a semiconductor manufacturing field or the like.

[0002]

2. Description of the Related Art Conventionally, this kind of vacuum pump is described, for example, in Japanese Utility Model Laid-Open No. 1-80696. In this conventional vacuum pump, as shown in FIG. 3, an intake port B and an exhaust port C are opened on the upper surface and the lower portion of the casing A, respectively.
A pump element F including a stator D and a rotor E is provided in the casing A between the intake port B and the exhaust port C.
And the rotor E is linked to a rotor shaft H extending from a motor G provided in the casing A. Then, the intake port B of the casing A is connected to a semiconductor manufacturing room or the like, and the rotor E is rotated at a high speed with the driving of the shaft H, thereby exhausting the gas from the intake port B toward the exhaust port C. The semiconductor manufacturing room is evacuated.

Further, like the above-described vacuum pump, the intake port B is opened on the upper surface of the casing A, and the intake port B is connected to the semiconductor via an intake pipe extending upward from the casing A. In the case of connecting to a manufacturing room or the like, when assembling various parts in the semiconductor manufacturing room or performing maintenance and inspection work of the vacuum pump, mounting bolts or wafer fragments dropped into the semiconductor manufacturing room. Such foreign matter may be attracted to the intake port B and enter between the stator D and the rotor E of the pump element F from the intake port B to damage the pump element F. Therefore, in the above-described conventional vacuum pump, as shown in FIG.
Foreign matter introduced from a chamber such as the semiconductor manufacturing room is received by the wire netting I to prevent the foreign matter from entering the pump element F side.

[0004]

However, as mentioned above,
When the wire net I is stretched in the intake port B of the casing A, not only the structure becomes complicated and the cost becomes high, but also when the semiconductor manufacturing chamber or the like is evacuated, it is generated on the semiconductor manufacturing chamber side. Reaction products and the like adhere to the wire mesh I, causing the wire mesh I to be clogged, increasing the passage resistance, and causing a problem that the performance of the pump element F is reduced.

The present invention has been made in view of the above problems, and has as its object to use a wire mesh without using a wire mesh.
It is an object of the present invention to provide a vacuum pump capable of preventing foreign matters such as mounting bolts and wafer fragments from entering the pump element side and preventing accidental damage of the pump element.

[0006]

In order to achieve the above object, according to the present invention, an intake port is provided at an upper portion of a casing 1 in which a pump element 4 including a stator 2 and a rotor 3 rotatable with respect to the stator 2 is provided. In a vacuum pump provided with an exhaust port 12 at a lower portion, an upper surface of the casing 1 is closed, and the intake port 11 is opened on one side of an upper portion of the casing 1 in a lateral direction. Inside the intake port 11, a blocking wall 7 facing the intake port 11 is provided.

As the rotor 3, a screw rotor provided with a screw groove 35 on the outer peripheral surface is used. The outer diameter of the screw rotor is made smaller than that of the casing 1, and the outer circumference of the screw rotor 36 is A stator 25 having an inner peripheral surface facing the outer peripheral surface is provided, and an intake chamber 13 is formed between the outer peripheral surface of the stator 25 and the inner peripheral surface of the casing 1. 1
1 may be opened.

[0008]

In the above-described vacuum pump, the upper surface of the casing 1 is closed, and the intake port 11 connected to the semiconductor manufacturing chamber or the like is opened on one side of the upper portion of the casing 1 in the lateral direction. Even if foreign matters such as bolts and wafer fragments that have fallen into a chamber such as the semiconductor manufacturing chamber are attracted and enter the casing 1 from the horizontally oriented intake port 11, the intake air in the casing 1 is not affected. Since the blocking wall 7 is provided at a portion facing the opening 11, the blocking wall 7 can prevent foreign matter from entering the pump element 4 side. 4 can be prevented from being damaged. Further, since the vacuum pump is configured to prevent foreign matter from entering the pump element 4 side without using a wire mesh unlike a conventional pump, the wire mesh is clogged with a reaction product or the like. Thus, the performance of the pump element 4 does not deteriorate due to the occurrence, and the structure is simple and the cost can be reduced.

Further, a screw rotor provided with a screw groove 35 on the outer peripheral surface is used as the rotor 3, and the outer diameter of the screw rotor 36 is made smaller than that of the casing 1. A stator 25 having an inner peripheral surface facing the outer peripheral surface is provided, and an intake chamber 13 is formed between the outer peripheral surface of the stator 25 and the inner peripheral surface of the casing 1. When the port 11 is opened in the horizontal direction, the above-described blocking wall 7 is fixed by the stator 25 facing the screw rotor 36.
The same operation and effect as described above can be exerted. Therefore, without changing the outer diameter of the casing 1,
Foreign matter can be prevented from entering the pump element 4 side.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The vacuum pump shown in FIG. 1 is used for evacuation in a semiconductor manufacturing room or the like. The basic structure of the vacuum pump will be briefly described. An intake port 11 is provided in an upper portion of the casing 1, and an exhaust port 12 is provided on an outer peripheral side of a lower surface of the casing 1.
And a pump element 4 having a stator 2 fixed to the casing 1 and a rotor 3 rotated relative to the stator 2 inside the casing 1, and a lower surface 1b of the casing 1 Then, a motor housing 10 having a motor 5 therein is attached thereto, and a rotor shaft 6 extending from the motor 5 is connected to the rotor 3 in an interlocking manner. The rotation of the rotor shaft 6 accompanying the motor 5 causes the rotor 3 to rotate. Is rotated at a high speed with respect to the stator 2, so that the intake port 11 and the exhaust port 12
The semiconductor manufacturing chamber and the like connected to the suction port 12 are evacuated by vacuuming.

The vacuum pump shown in FIG. 1 includes a jig-burn type high vacuum stage pump element 4A and a jig-burn type low vacuum stage pump element 4B as the pump element 4, and these pump elements 4A, 4B are provided. Are arranged vertically above and below, respectively, and the high vacuum stage pump element 4A
Are a stator 22 having a large stationary blade 21 and a rotor 32 having a large moving blade 31 interposed between the stationary blades 21.
And the low vacuum stage pump element 4B
A stator 24 having a plurality of small-diameter stationary blades 23;
And a rotor 34 provided with a plurality of small-diameter moving blades 33 interposed between the stationary blades 23.

In the vacuum pump of the present invention, as shown in FIG. 1, the upper surface 1a of the casing 1 is closed. The suction chamber 13 is formed between the upper surface 1a of the casing 1 and the pump element 4A, and the intake chamber 11 is opened in the intake chamber 11. The high vacuum stage pump element 4A is formed inside the intake chamber 13. A cylindrical blocking wall 7 having a diameter larger than that of the rotor 32 and extending upward from the stator 22 and having a facing surface facing the intake port 11 is attached to the upper surface of the outer peripheral portion of the stator 22. The intake port 11
The mounting flange 11a having a large diameter is provided vertically, and mounting holes 1 are formed at a plurality of locations on the outer periphery of the mounting flange 11a.
1b is provided, and the suction port 11 is connected to the semiconductor manufacturing chamber directly or via a suction pipe by a fixing bolt (not shown) inserted into the mounting hole 11b.

As described above, since the air inlet 11 is opened laterally on one side of the upper part of the casing 1, mounting bolts dropped into a chamber such as the semiconductor manufacturing chamber, wafer fragments, etc. Even if foreign matter is attracted toward the intake port 11 and enters the casing 1 through the intake port 11, the interior of the intake chamber 13 in the casing 1 is opposed to the intake port 11. Since the shielding wall 7 is provided, foreign matter that has entered the casing 1 from the intake port 11 can be received by the shielding wall 7 and prevented from entering further inward. The blocking wall 7 can prevent foreign matter from entering the pump element 4 side, so that the pump element 4 can be prevented from being damaged due to foreign matter entering.

Moreover, in the above-mentioned vacuum pump, since the foreign matter is prevented from entering the pump element 4 side without using a wire net unlike the conventional vacuum pump, the wire net is made of the semiconductor material. The performance of the pump element 4 is not degraded due to clogging with a reaction product or the like generated in the manufacturing room, and the structure can be simplified and the cost can be reduced.

Further, in the above embodiment, the pump element 4 using a jigburn type high vacuum stage and low vacuum stage pump element 4A, 4B is shown.
As shown in FIG. 2, the pump element 4 includes a screw type high vacuum stage pump element 4C and a jigburn type low vacuum stage pump element 4D.
The present invention can also be applied to a composite type in which C and 4D are arranged vertically. That is, the high vacuum stage pump element 4C
A screw rotor 36 having a screw groove 35 on the outer peripheral surface and having a diameter smaller than that of the casing 1, and disposed around the outer periphery of the screw rotor 36 so as to face the screw groove 35, and the inner periphery is flush. And the low vacuum stage pump element 4D includes a plurality of moving blades 37 similarly to the low vacuum stage pump element 4B described above.
And a stator 27 having a plurality of stationary blades 26 interposed between the moving blades 37.

The stator 25 constituting the screw-type high-vacuum stage pump element 4C having the above-described structure is used.
An intake chamber 13 is formed between the outer peripheral surface of the casing 1 and the inner peripheral surface of the casing 1.
In the same manner as in the embodiment shown in FIG. 1, the intake port 11 having the mounting flange 11a is opened in the lateral direction,
5 is opposed to the intake port 11, and the stator 25 is used as the blocking wall 7.

In the above configuration, the intake port 11 is connected to the intake chamber 13 at the time of maintenance and inspection work or when assembling various components into a chamber such as the semiconductor manufacturing room.
Foreign matter, such as the bolts and wafer fragments, is attracted to the suction port 11 side and enters the suction chamber 13 in the casing 1 from the suction port 11. The inlet 1
Since the stator 25 of the screw type pump element 4 </ b> C provided in opposition to 1 also serves as the blocking wall 7, the foreign matter can be prevented from entering the pump element 4 side by the stator 25. Therefore, by using the stator 25 of the screw-type pump element 4C, the pump element 4 can be formed without separately changing the outer diameter of the casing 1 or providing a special blocking wall.
This can prevent damage accidents.

[0018]

As described above, according to the present invention, the intake port 11 is provided at the upper part of the casing 1 in which the pump element 4 including the stator 2 and the rotor 3 rotatable with respect to the stator 2 is installed, and the lower part is provided at the lower part. In a vacuum pump provided with an exhaust port 12, the upper surface of the casing 1 is closed, and the intake port 11 is opened on one side surface of the upper portion of the casing 1 in a lateral direction. , The intake port 1
Since the blocking wall 7 opposed to 1 is provided, even if foreign substances such as bolts and wafer fragments which have fallen into a chamber such as the semiconductor manufacturing chamber are attracted and enter the casing 1 from the intake port 11, The intrusion of the foreign matter into the pump element 4 side can be prevented by the blocking wall 7 provided in the casing 1 at a position facing the intake port 11, and therefore, the pump element 4 can be prevented from entering by the foreign matter. Damage accidents can be prevented. Moreover, in the above-described vacuum pump, foreign substances can be prevented from entering the pump element 4 side without using a wire mesh unlike a conventional pump, so that the wire mesh may be clogged with a reaction product or the like. Without deteriorating the performance of the pump element 4 due to
Moreover, the structure is simple and the cost can be reduced.

Further, as the rotor 3, a screw rotor provided with a screw groove 35 on the outer peripheral surface is used. The outer diameter of the screw rotor 36 is made smaller than that of the casing 1, and the outer circumference of the rotor 36 is A stator 25 having an inner peripheral surface facing the outer peripheral surface is provided, and an intake chamber 13 is formed between the outer peripheral surface of the stator 25 and the inner peripheral surface of the casing 1. When the mouth 11 is opened in the lateral direction, the above-mentioned blocking wall 7 can be used also by the stator 25 facing the screw rotor 36, so that the outer diameter of the casing 1 can be changed, It is possible to prevent the foreign matter from entering the pump element 4 side without providing a blocking wall.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a vacuum pump of the present invention.

FIG. 2 is a longitudinal sectional view showing another embodiment.

FIG. 3 is a longitudinal sectional view showing a conventional vacuum pump.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Casing 11 Intake port 12 Exhaust port 13 Intake chamber 2 Stator 25 Stator 3 Rotor 35 Screw groove 36 Screw rotor 4 Pump element 7 Blocking wall

Claims (2)

(57) [Claims] 1. A vacuum pump comprising a casing 1 in which a pump element 4 comprising a stator 2 and a rotor 3 rotatable with respect to the stator 2 is provided. In the above, the upper surface of the casing 1 is closed, and the intake port 11 is opened in one side of the upper part of the casing 1 in the lateral direction.
A vacuum pump, wherein a blocking wall 7 facing the intake port 11 is provided inside the intake port 11. 2. The rotor 3 is composed of a screw rotor having a screw groove 35 provided on an outer peripheral surface thereof. The outer diameter of the screw rotor is made smaller than that of the casing 1, and the outer peripheral surface of the rotor 36 is formed around the outer periphery of the rotor 36. The intake chamber 13 is formed between the outer peripheral surface of the stator 25 and the inner peripheral surface of the casing 1, and the intake port 11 is formed in the intake chamber 13. The vacuum pump according to claim 1, which has been established.