JPH05118288A - Bearing case for vacuum pump - Google Patents

Abstract

PURPOSE:To prevent clogging of various types of piping and the like due to corrosion inside a cooling water passage in a lubricating oil reservoir constituted of a bearing case for housing a bearing for supporting a rotation shaft by incorporating a tube of a corrosion resistant material as a cooling water passage in the bearing case. CONSTITUTION:In a vacuum pump, a pair of rotating bodies 2 engaging with each other are arranged in a casing 1 and bearings 5, 6 to rotating-support respective rotating bodies 2 are housed respectively in bearing cases 10, 11. The bearing cases 10, 11 are respectively serving also as lubricating oil reservoirs, and lubricating oil 38 is housed therein at a predetermined level being a level for submerging an outer circumferential surface of gears 8. In this case, a tube 15 formed of a stainless tube and the like and made of a corrosion resistant material is insert-molded integrally with each of the bearing cases 10, 11 at each bottom of the bearing cases 10, 11. Stainless pipes 17 for a cooling water supply passage are connected to both ends of each tube 15 to flow cooling water in each tube 15 so as to cool the bearing cases 10, 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bearing case of a vacuum pump, and more particularly to a bearing case of a vacuum pump in which a bearing case which supports a rotating shaft of the vacuum pump constitutes a lubricating oil sump.

[0002]

2. Description of the Related Art Conventionally, there has been known a vacuum pump in which rotors having rotors are provided adjacent to each other along a rotation axis, and rotors facing each other rotate in opposite directions to perform suction and exhaust. The rotors for vacuum pumps rotate without contacting each other with a slight gap maintained between the rotors facing each other and between the rotors and the casing.

However, the rotary shaft supporting the rotor is provided with bearings at both ends thereof, and the rotor and the rotary shaft are rotatably supported by the bearings. Gears are provided at the shaft ends of the pair of rotary shafts, respectively, so that power is transmitted from one rotary shaft to the other rotary shaft. In order to lubricate the bearings, gears, and other devices, the bearing case of the vacuum pump constitutes a lubricating oil sump, and the lubricating oil accommodated in the lubricating oil sump causes the bearings, gears, etc. to be oiled. It is supposed to be lubricated.

Next, a bearing case of a conventional vacuum pump will be described with reference to FIG. In FIG. 4, reference numeral 31
Is a bearing case, and this bearing case constitutes a lubricating oil sump. A cooling water jacket 32 is formed on the bottom of the bearing case 31. Cooling water jacket 32
A cooling water tube 33 is connected to the cooling water tube 33 via a tube joint 36, and cooling water is supplied into the cooling water jacket 32.

On the other hand, the bearing case 31 accommodates gears 35, 35 provided at the ends of the pair of rotary shafts 34, 34, and the rotary shaft 31 is housed in the bearing case 31. Bearings for bearing are also housed (not shown). Then, the lubricating oil 38 contained in the bearing case 31 forming the lubricating oil sump lubricates the gear and the bearing. The lubricating oil warmed by this lubrication is cooled by the cooling water in the cooling water jacket 32.

[0006]

However, in the above-mentioned bearing case of the conventional vacuum pump, the inside of the cooling water jacket 32 is corroded and the cooling water is contaminated, and as a result, the flow switch in the circulation path of the cooling water jacket. However, there is a problem in that the equipment having a narrow flow passage such as a flow meter, a coupler and a valve may be clogged, and the cooling water may not flow.

In addition, in instruments such as a flow meter, there is a problem that a pointing portion becomes invisible due to contaminants due to corrosion, and the contaminants cause malfunction in the flow switch.

Further, since the cooling water circulates in the factory, there is a problem that the contamination of the cooling water itself affects other devices other than the vacuum pump.

The present invention has been made in view of the above points, and an object of the present invention is to form a cooling tube for cooling lubricating oil in a bearing case with a corrosion resistant material.
It is an object of the present invention to provide a bearing case for a vacuum pump, which is capable of removing the dirt due to the corrosion by incorporating this tube in the bearing case.

[0010]

In order to achieve the above-mentioned object, in the bearing case of the vacuum pump of the present invention, the bearing case accommodating the bearing for supporting the rotary shaft of the vacuum pump constitutes a lubricating oil sump. In a bearing case of a vacuum pump that lubricates equipment such as bearings and gears in or above the oil surface of the lubricating oil sump, this bearing case incorporates a tube of corrosion resistant material as a cooling water flow path. It is characterized by that.

[0011]

According to the present invention having the above-mentioned structure, since the bearing case has the tube of the corrosion resistant material built therein as the cooling water passage, the cooling water passage is not corroded and is provided in the cooling water circulation passage. There is no risk that the various pipes and equipment will be clogged with contaminants, and each equipment will operate normally. That is, there is no risk of clogging equipment such as the flow switch or flow meter in the circulation path of the cooling water, and no malfunction of the flow switch or the like. Also,
It is possible to prevent a situation in which the indicating portion of the instrument is invisible due to contaminants due to corrosion.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A bearing case for a vacuum pump according to the present invention will be described below with reference to FIGS.

FIG. 1 is a diagram showing the overall construction of a vacuum pump incorporating the bearing case according to the present invention, and FIG.
It is sectional drawing which followed the II-II line.

In FIGS. 1 and 2, reference numeral 1 is a casing, and inside the casing 1, a pair of rotating bodies 2 and 2 are arranged. The rotating body 2 includes a rotating shaft 3 and a plurality of rotors 4 arranged along the axial direction of the rotating shaft. The rotating body 2 is rotatably supported by a bearing 5 at one end thereof and a bearing 6 at the other end thereof, and one rotating body 2 is connected to a motor 7. Then, from one rotating body 2 to the other rotating body 2
Is transmitted by a gear 8 (only one gear is shown in FIG. 1) fixed to the shaft end of the rotary shaft 3,
The pair of rotating bodies 2 and 2 rotate in mutually opposite directions, and rotors facing each other with a slight gap rotate in mutually opposite directions to perform intake and exhaust.

The bearing 5 is housed in the bearing case 10, and the bearing 6 and the gear 8 are also housed in the bearing case 11. The bearings 5, 6 and the gear 8 are lubricated by the lubricating oil in the bearing cases 10, 11.

Next, the detailed structure of the bearing cases 10 and 11 will be described with reference to FIG. In FIG. 3, the bearing cases 10 and 11 form a lubricating oil sump, that is, the lubricating oil 38 is contained in the bearing case up to a predetermined liquid level. The liquid surface is adapted to immerse the outer peripheral portions of the gears 8, 8. At the bottom of the bearing cases 10 and 11, a tube 15 made of a corrosion resistant material such as a stainless steel tube is cast around the bearing cases. This tube 1
5 is connected to the stainless pipes 17 and 17 via the tube joints 16 and 16 at both ends thereof, and the cooling water is supplied to the stainless pipe 17 by a cooling water supply path (not shown). Is supplied to the inside of the tube 15 to cool the bearing cases 10 and 11.

As described above, according to this embodiment, the tube 15 for supplying the cooling water is provided integrally with the bearing cases 10 and 11, and the cooling water is supplied to the tube 15 made of the stainless pipe. Unlike the cooling water jacket method, there is no material that corrodes the cooling water circulation path, and therefore the cooling water is not contaminated by contaminants. As a result, it is possible to operate each device normally without the risk of contaminating the various pipes provided in the cooling water circulation path and the narrow flow paths of devices such as flow switches, flow meters, fittings and valves. Become. Further, since there is no risk of the cooling water being contaminated, it is possible to eliminate the influence of contaminants on equipment other than the vacuum pump.

In this embodiment, the stainless steel tube is cast into a bearing case made of an aluminum material, but the bearing case is bored and then a tube made of a corrosion resistant material such as a stainless steel tube is press-fitted into the bearing case. Alternatively, they may be integrally provided by cold fitting or shrink fitting.

[0019]

As described above, according to the present invention, since the bearing case incorporates the tube of the corrosion resistant material as the cooling water passage, the inside of the cooling water passage is not corroded.
Various pipes and each device provided in the circulation path of the cooling water are not likely to be clogged with contaminants, and each device can operate normally. That is, there is no risk of clogging equipment such as the flow switch or flow meter in the circulation path of the cooling water, and no malfunction of the flow switch or the like.
In addition, it is possible to prevent a situation in which the indicating portion of the instrument is invisible due to a contaminant due to corrosion.

[Brief description of drawings]

FIG. 1 is a sectional view showing the overall structure of a vacuum pump incorporating a bearing case of the vacuum pump according to the present invention.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a sectional view showing an embodiment of a bearing case of the vacuum pump according to the present invention.

FIG. 4 is a sectional view showing a bearing case of a conventional vacuum pump.

[Explanation of symbols]

 1 Casing 2 Rotating Body 3 Rotating Shaft 4 Rotor 5,6 Bearing 7 Motor 8 Gear 10, Gear 11 and 11 Bearing Case 15 Tube 16 Tube Joint 17 Stainless Pipe

Front Page Continuation (72) Inventor Katsuaki Usui 4-2-1 Motofujisawa, Fujisawa City, Kanagawa Prefecture EBARA Research Institute

Claims (2)

[Claims] 1. A bearing case accommodating a bearing for supporting a rotary shaft of a vacuum pump constitutes a lubricating oil sump, and equipment such as bearings and gears in or above the oil level of the lubricating oil sump. A bearing case of a vacuum pump, wherein a tube made of a corrosion resistant material is incorporated as a cooling water flow path in the bearing case of the vacuum pump. 2. The bearing case of the vacuum pump according to claim 1, wherein the tube is integrally encased in the bearing case.