JPS6211353Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention is a mechanical booster pump that can reduce the differential pressure between the pump chamber and mechanical chambers such as bearing chambers and gear chambers adjacent to both sides of the pump chamber. This invention relates to a pressure adjustment device in a machine room.

[Conventional technology]

Conventionally, in this type of mechanical booster pump (hereinafter simply referred to as a booster), the machine chamber is communicated with the exhaust system via a fluid flow path to reduce the differential pressure between the machine chamber and the pump chamber. It is common to prevent disadvantages such as an increase in required power, poor lubrication, or a shortened life of the shaft sealing member that separates the machine room and the pump room. However, with this simple configuration, fluid existing in the exhaust system enters and exits the machine chamber through the fluid flow passage as a transient phenomenon to reduce the differential pressure between the machine room and the pump chamber. If the fluid is organic or highly oxidizing, there are disadvantages in that it is likely to cause deterioration of the lubricating oil injected into the machine chamber and corrosion of bearings provided in the machine chamber.

Therefore, as disclosed in Utility Model Application No. 52-93912, a check valve is inserted in the fluid flow path to allow flow from the machine room to the exhaust system, thereby preventing harmful exhaust gases from entering the machine room. Measures have been proposed to prevent this. However, this means cannot effectively eliminate the pressure difference between the machine chamber and the pump chamber when the pressure is relatively low.

In view of these problems, the inventor of the present invention
In No. 41312, the booster machine room is equipped with an exhaust system separate from the pump room, and when the pressure in the pump room (exhaust system) becomes higher than the machine room, atmospheric air is introduced into the machine room. I am proposing something. However, in this case, the problem is that the exhaust system becomes complicated in order to adjust the pressure in the machine room. Specifically, it is necessary to add vacuum pumps, piping, and valves, and also install a differential pressure gauge. There is a problem with this.

[Problem that the invention attempts to solve]

The present invention was developed by focusing on the problems of the prior art described above, and is a simple means that requires only a single switching valve to be inserted into the fluid flow path that communicates the booster machine room and the exhaust system. The present invention aims to realize a pressure adjustment device for a booster machine room that can effectively prevent the generation of differential pressure between the pump room and the machine room, and can also reliably eliminate the problem of harmful gases entering the machine room from the exhaust system. .

[Means for solving problems]

In order to achieve such an objective, the present invention is a mechanical booster pump in which a machine chamber adjacent to the pump chamber via a shaft seal member is communicated with an exhaust system via a fluid flow path in which a switching valve is inserted. The switching valve has a valve box, a first port provided in the valve box at one end, an air inlet port at an end that is closed by an air inlet valve, and an air inlet port at the other end that communicates with the machine room. A second port communicates with the exhaust system, and a valve holding hole that is slidably fitted into the valve holding hole and is displaced in the axial direction according to the pressure of both ports and communicated with the second port. a piston valve that opens and closes a third port that opens in the valve holding hole; and a piston valve that protrudes from the piston valve toward the first port and comes into contact with the atmosphere introduction valve when the piston valve is displaced toward the first port. The device is characterized in that it includes a push rod for opening the air inlet.

[Effect]

The switching valve according to the present invention operates as follows.
First, when the pressure in the machine chamber and the pressure in the exhaust system are equal to each other, the piston valve in the valve holding hole is located at the neutral position to close the third port and cut off the fluid flow path. Next, if the pressure in the machine chamber is higher than the pressure in the exhaust system, the piston valve is displaced to the second port side and the third
A port opens in the valve retaining hole, which allows fluid to flow from the machine room to the exhaust system to eliminate the differential pressure between the two.
On the other hand, when the pressure in the exhaust system becomes relatively high, the piston valve is displaced toward the first port, and when the third port is closed, the push rod protruding from the piston valve is moved toward the first port. It comes into contact with the atmosphere inlet valve at the end of the holder and pushes it open. Atmospheric air is then introduced into the machine room through the air inlet valve to eliminate the differential pressure with the exhaust system.

In this way, in the machine room pressure adjustment device of the present invention,
By simply inserting a single switching valve in the fluid flow path, the generation of differential pressure between the machine room and the exhaust system (pump room) can be effectively eliminated, and harmful gases from the exhaust system can be prevented from entering the machine room. No intrusion at all.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

The booster 1 has an intake port 2 connected to a tank 5 etc. via an intake pipe line 4, and an oil rotary pump 8 connected to its exhaust port 6 via an exhaust pipe line 7 to connect the tank 5 etc. The fluid inside is evacuated by the booster 1 and the oil rotary pump 8 which are connected in series.

Here, the booster 1 has a pair of rotating shafts 11,
A pump chamber 15 that accommodates rotors 13 and 14 supported by rotors 12 and communicates with the intake port 2 and exhaust port 6, and a partition wall 1 on one side of the pump chamber 15.
6 and a bearing chamber 1 adjacent to the other end of the pump chamber 15 via a partition wall 18.
9 are provided in a common casing 21. The gear chamber 17 includes the rotating shafts 11 and 1.
2 and gears 24 and 25 that connect the two rotating shafts 11 and 12 in a synchronously rotatable manner. Bearings 26 and 27 that pivotally support the other end portions of 11 and 12 are housed therein. Further, in each of the partition walls 16 and 18 through which the rotating shafts 11 and 12 penetrate, a shaft sealing member, for example, an oil seal, is provided to separate the pump chamber 15 and gear chamber 17 and the pump chamber 15 and bearing chamber 19, respectively. There are 28. Note that 29 is an air passage that communicates between the gear chamber 17 and the upper end of the bearing chamber 19, 31 is an oil passage that communicates between the gear chamber 17 and the lower end of the bearing chamber 19, and 32 is an oil passage that communicates with the gear chamber 17 and the lower end of the bearing chamber 19. Lubricating oil is stored at the bottom of each bearing chamber 19, and 33 is an electric motor that rotationally drives one of the rotating shafts.

The machine chamber 34 consisting of the gear chamber 17 and the bearing chamber 19 is connected to the exhaust system 3 through a fluid flow path 35.
It is connected to 6. The exhaust system 36 includes the intake pipe 4, the pump chamber 15, the exhaust pipe 7, etc., and the fluid passage 35 is connected to the exhaust pipe 7 midway.

In such a booster 1, the fluid flow passage 35 is divided into a machine room side passage 37 and an exhaust system side passage 38 in the middle of the fluid flow passage 35, and the machine room 3
A single switching valve 39 is inserted to connect the exhaust gas 4 to the exhaust system 36 or the atmosphere at a predetermined timing. As shown in FIG. 2, the switching valve 39 includes the following components inside a cylindrical valve box 43. That is, a valve holding hole 46 having a large diameter in the axial direction is provided in the center of the interior of the valve box 43, and a first port 47 is provided at one end of the hole 46, and a second port 48 is provided at the other end thereof. The first port 47 has an air inlet 40 at an end that opens onto the surface of the valve box 43 . The atmosphere inlet 40 is connected to an auxiliary valve mechanism 44 inside a perforated case 53 that is attached to the end of the valve box 43.
It is normally closed by an atmospheric air introduction valve 51 installed together with the air inlet valve. That is, a spring 52 is interposed between the inner surface of the case 53 and the atmosphere introduction valve 51 to bias the atmosphere introduction valve 51 into contact with the atmosphere introduction port 40.
Further, the first port has a first connection port 41 which is opened in the peripheral wall of the first port. And this first
The machine room side passage 37 is connected to the connection port 41,
The first port 47 and the machine room 34 are communicated here. On the other hand, the second port 48 is provided with a second connection port 42 at an end that opens onto the surface of the valve box 43.
An exhaust system side passage 38 is connected to this second connection port 42, and the second port 48 and the exhaust system 36 are communicated here.

A piston valve 54, which constitutes the main valve mechanism 45 of the switching valve 39, is fitted into the valve holding hole 46 so as to be slidable in the directions of arrows X and Y in the figure.
Therefore, this piston valve 54 is displaced in the axial direction (X, Y direction) due to the pressure of the first port 47 and the second port 48 on both sides. A pair of springs 55 and 56 are interposed on both sides of the piston valve 54 to return the piston valve to a predetermined neutral position. A third port 49 is opened on the inner periphery of the valve holding hole 46 into which the piston valve 54 is fitted, forming a bypass passage that communicates the valve holding hole 46 with the second port 48 . This third port 49 is opened and closed by displacement of the piston valve 54. That is, the third port 49 is opened only when the piston valve 54 moves in the X direction from the neutral position.

The first port 47 of the piston valve 54
A long, small-diameter push rod 57 is integrally provided on the side and projects from the end surface thereof and is inserted into the first port 47 .
When the piston valve 54 is in the neutral position, the tip of the push rod 57 is slightly separated from the atmosphere inlet valve 51 that blocks the atmosphere inlet 40, but if the piston valve 54 is in the Y direction, The length is adjusted so that when it moves by a certain amount of displacement, it comes into contact with the inner surface of the atmosphere inlet valve 51 and pushes it up from the atmosphere inlet 40 to open the atmosphere inlet 40.

Next, the operation of this embodiment will be explained.

When the booster 1 starts operating and the pressure in the exhaust system 36 becomes lower than the pressure in the machine room 34, the pressure at one end of the valve holding hole 46 communicating with the machine room 34 via the machine room side passage 37 decreases. and a valve holding hole 4 communicating with the exhaust system 36 via the exhaust system side passage 38.
A difference occurs between the pressure at the other end of 6 and the pressure at the other end. and,
When the difference exceeds a certain level, the piston valve 54 moves in the direction of the arrow X against the biasing force of the spring 56 due to the pressure difference. Then, the third port 49 is opened and the machine room side passage 37 and the exhaust system side passage 38 are connected to the first port 47 and the valve holding hole 4.
6 and a third port 49. Therefore, the gas in the machine chamber 34 is exhausted through the fluid flow path 35, and the pressure in the machine chamber 34 and the pressure in the pump chamber 15 are approximately balanced.

Next, when the pressure in the exhaust system 36 increases from such a pressure state, the pressure at one end of the valve holding hole 46 becomes higher than the pressure at the other end, contrary to the above. When the difference exceeds a certain level, the piston valve 54 moves in the direction of the arrow Y against the biasing force of the spring 55 due to the pressure difference. Then, the third port 49 is closed and communication between the machine room side passage 37 and the exhaust system side passage 38 is cut off. At the same time, a push rod 57 protruding from the piston valve 54 presses the atmosphere introduction valve 51 in the direction of arrow Y against the biasing force of the spring 52 to open the atmosphere introduction port 40. Therefore, the exhaust system side passage 38 is closed, and the machine room side passage 37 is opened to the atmosphere through the first port 47, and the pressure inside the machine room 34 increases and the pressure inside the pump chamber 15 increases. It will almost balance out.

Note that when the differential pressure between the machine room 34 and the exhaust system 36 is small, communication between the machine room side passage 37 and the exhaust system side passage 38 is cut off, and the atmospheric air inlet 40 also remains closed.

As described above, according to the machine room pressure regulating device according to the present invention, when the pressure in the machine room 34 is higher than the pressure in the exhaust system 36, the machine room 34 is connected to the exhaust system through the fluid flow path 35. 36 to exhaust the air in the machine room 34. Conversely, when the pressure in the exhaust system 36 is higher than the pressure in the machine room 34, the exhaust system 3
6 and the machine room 34 to open the machine room 34 to the atmosphere, the fluid present in the exhaust system 36 is not introduced into the machine room 34 at all, and the machine room 34 is always connected to the machine room 34. The pressure inside the pump chamber 15 can be approximately balanced with the pressure inside the pump chamber 15. Therefore, even if the fluid present in the exhaust system 36 is organic or highly oxidizing, these harmful fluids may enter the machine room 34 and cause the lubricating oil 32 injected into the machine room 34 to leak. bearings 2 housed in the machine room 34.
No inconvenience such as corrosion of gears 2, 23, 26, 27 or gears 24, 25 occurs.

The greatest feature of the device according to the present invention is that the above-mentioned required effects can be obtained by simply inserting a single switching valve 39 into the fluid flow path 35.

[Effect of idea]

As described above, the machine room pressure regulating device of the present invention can be easily operated by simply inserting a single switching valve having the configuration already detailed in the fluid flow path that communicates the booster machine room and the exhaust system. With this structure, it was possible to reduce the differential pressure between the machine room and the exhaust system required for the booster, and to prevent harmful exhaust gases from entering the machine room.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, with FIG. 1 being a diagram explaining the principle, FIG. 2 being a sectional view showing the main parts, and FIG. 3 being a broken perspective view. 1... Booster, 15... Pump room, 34...
Machine room, 35...Fluid flow path, 36...Exhaust system,
37...Machine room side passage, 38...Exhaust system side passage,
40...Atmospheric introduction port, 43...Valve box, 46...Valve holding hole, 47...First port, 48...Second port, 49...Third port, 51...Atmospheric introduction valve,
54... Piston valve, 57... Push rod.

Claims (1)

[Scope of utility model registration request] A mechanical booster pump in which a machine chamber adjacent to the pump chamber via a shaft sealing member is communicated with an exhaust system via a fluid flow path in which a switching valve is inserted, the switching valve being connected to a valve box, A valve that is provided in the valve box and has an atmosphere inlet at one end of which a first port is closed by an atmosphere inlet valve, and communicates with the machine room, and a second port at the other end communicates with the exhaust system. a holding hole, and a third port that is slidably fitted into the valve holding hole and is displaced in the axial direction according to the pressure of both side ports to communicate with the second port and open to the valve holding hole. and a push rod that protrudes from the piston valve toward the first port and comes into contact with the atmosphere inlet valve to open the atmosphere inlet when the piston valve is displaced toward the first port. A mechanical chamber pressure adjustment device for a mechanical booster pump, characterized in that it is constructed of: