JPS5854273B2 - Vane type gas compression device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a compression device, and more particularly to a vane-type gas compression device suitable for compressing gas using a vane-type compressor.

When compressing a gas, for example air, it is customary for economic reasons to compress it at high speed in order to increase the output per volume of the compressor.

Compressing air at high speeds prevents heat exchange between the air and the walls surrounding it, and the air is compressed adiabatically.

The initial pressure and volume of air are Pl, ■1 Pressure after compression,
The volume is P2. ■It is known that if 2 is used, the respective relationships will be as follows.

However, K is the ratio of specific heat at constant pressure to specific heat at constant volume, and is, for example, 1.4 in the case of air.

On the other hand, when the air is compressed isothermally, not at high speed but slowly so that the temperature of the air does not rise, the change in pressure and volume of air is P2.v2-Pl.■1.

FIG. 1 shows this relationship, where the dotted line al] is the change in pressure and volume in the case of adiabatic compression, and the solid line ab' is the change in pressure and volume in the case of isothermal compression.

Compared to adiabatic compression, isothermal compression has an area a surrounded by solid lines and dotted lines.
The amount of work corresponding to bb' is small.

In other words, it is clear that a compressor that performs isothermal compression consumes less power than a compressor that performs adiabatic compression.

Since conventional compressors perform adiabatic compression, the efficiency of the compression itself is poor.Therefore, improved rotary compressors use a large amount of cooling oil to cool the air being compressed. ○Also, if we consider it from a mechanical point of view,
BACKGROUND ART Conventionally, a reciprocating compressor composed of a crank mechanism and a piston mechanism has been widely used as a typical compressor.

Although this type of compressor is most suitable as a large-capacity, high-output compressor, it has the following drawbacks.

(1) The vibration is strong.

(2) The pulsation of the discharged gas is large.

(3) Requires a large installation area.

etc.

On the other hand, since rotary compressors can overcome the above-mentioned drawbacks of reciprocating compressors, their field of use is rapidly expanding.

In particular, a compressor using a movable vane type so-called vane pump is a typical rotary compressor.

The main parts of a vane compressor are the casing 1 and the rotor 2' as shown in Figure 2. ? The rotor 2 is rotatably held eccentrically with respect to the casing 1, and a plurality of grooves are bored in the rotor 2 so that the vanes 3 can slide in the radial direction.

Therefore, as the rotor 2 rotates, the base 73 rotates while being in close contact with the inner surface of the casing 1 due to centrifugal force.

The space volume surrounded by the rotor 2, the casing 1''J?, and the vanes 3 changes sequentially as the rotor 2 rotates, so gas is sucked in from the suction port S, pressure is applied, and compressed air is discharged from the discharge port. It is something.

In this way, in order to obtain high-pressure compressed air with a vane type compressor, air is sucked from the suction port S, and the air is sucked into spaces A and B.

The compressed air is sequentially compressed at C and high-pressure compressed air is discharged from the discharge port.

Therefore, the inhaled air is in spaces A and B. It is compressed from atmospheric pressure to high pressure in three stages (C).

As a result, adiabatic compression is repeated within the compressor, and the discharged air becomes hot, so a cooling method is used in which cooling oil is directly injected into the casing 1.

This method has both a lubricating effect and a sealing effect, and water vapor in the sucked air and a large amount of cooling oil are pumped inside the compressor and stirred at high speed.

Therefore, the oil and water are completely mixed and form a colloidal state like a so-called petroleum emulsion, causing the vane to swell and weaken.

In addition to this, additional energy sources such as a pump for refueling and an oil/water separator are required, resulting in an increase in power consumption, which is not a desirable method.

Furthermore, each space partitioned by the vane 3 has a large difference in air pressure, and a strong differential pressure is applied to the vane 73.

This causes significant wear on the sliding surfaces of the vanes 3 and the rotor grooves, resulting in extremely low durability dust.

An object of the present invention is to solve the above-mentioned problems of the prior art by using a vane type compressor and connecting the corresponding sections of each compression stage and the next compressor by a group of pipes interposed in a cooling device. Another object of the present invention is to provide a vane type gas compression device capable of highly efficient compression by radiating heat and cooling during the compression process to perform compression in a nearly isothermal state, and by performing compression with less power consumption.

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 3 is an explanatory diagram showing the configuration of a three-stage vane type compression device.

It is composed of a plurality of vane type compressors from the first stage to the final stage (third stage in Figure 3).The first stage compressor 4 has a suction port So, and the final stage compressor 6 has a are each equipped with one discharge port Do.

The n-stage compressors 4 and 5 (first-stage and second-stage compressors in FIG. 3) each have an intermediate discharge port D11. D12. D
13. Dl4 button and D21°D22, D23, D2
4, and the (n+1)th membrane compressor 5 and 6 (third
(in the figure, the second stage director and the third stage) each have an intermediate suction port 82.
1.822.

823.824 button and S31, S32.833.

834.

One or more vanes 31゜32.33 are always interposed between these mutually adjacent intermediate discharge ports and intermediate suction ports, and intermediate discharge ports D11゜Dl 2 , Dl 3
, Dl 4 button and D21. D22°D23, D24 and their corresponding intermediate intake ports 821.822.823
, S24 and S31°832, S33.834 are pipe groups P11°Pl2., which are interposed in the cooling devices 7 and 8, respectively. Pl3. Pl4 button and P21
, P22.

Connected by P23 and P24.

Furthermore, the compressors 4.5, 6 are connected to the drive unit 1 via a drive shaft 9.
0 so that it can rotate.

The effects of the vane type compression device having the above configuration will be explained.

First, when the drive device 10 rotates in the direction of the arrow, the rotors 2 of each of the first to third stage compressors 4, 5, and 6 are rotated through the drive shaft 9.
L22゜23 also rotates in the direction of the arrow, and the respective rotors 21
The vanes 31, 32.33 mounted at 22.23 rotate in close contact with the inner surface of the casing 11.12.13 due to centrifugal force.

The first stage compressor 4 sucks air from the suction port So and compresses it sequentially, but the air in the compression process is transferred to the intermediate discharge port D11.・Dl2. It is sequentially discharged from Dl3° to Dl4.

This discharge port D11°Dl2. Dl3. Dl4. The air discharged from the pipes P11, Pl 2 and Pi
3, Pl 4, and is cooled by the cooling device 7 on the way to the intermediate suction port 821 of the second stage compressor 5, S22.
823.

You will be guided to S24.

At this time, intermediate discharge ports D11 and Dl2 of the first stage compressor 4,
Since the vane 31 is always interposed between Dl2 and Dl3, and between Dl3 and Dl4, air having different compression ratios is discharged.

This air with different compression ratios is supplied to the intermediate suction port S of the second stage compressor 5.
21.822, S23, and S24, and is compressed again and is passed through intermediate discharge ports D21 and D22 for each compression stage.
, D23 and D24.

This second stage compressor 5 also has intermediate suction ports 821 and 22.
, S22 and 23, S23 and 824, and between the intermediate discharge ports D21 and D22, D22 and D23, and D23 and D24, the vanes 32 are always interposed, so the compressed air of each compression stage is mixed. There's nothing to do.

Intermediate discharge ports D21 and D22 of the second stage compressor 5.

D23. The compressed air discharged from D24 passes through the pipes P21, P22, P23, P24, respectively, is cooled by the cooling device 8 on the way, and then passes through the intermediate suction ports 831, 832, 833, . You will be guided to S34.

In this third stage compressor 6, that is, the final stage compressor, the compressed air is again compressed at each compression stage, and high-pressure compressed air is discharged from the discharge port Do.

In this way, each of the first stage, second stage, and third stage compressors 4.5,
6, compressed air with different compression ratios is led to the pipes independently and passes through a cooling device in the middle, so the cooling effect of each can be improved.

Figure 3 shows an example using three compressors and two cooling devices, but by further increasing the number of compressors and cooling devices, it is possible to perform compression that closely approximates ideal isothermal compression. It is something.

Here, the discharge amount of the second stage compressor 5 and the third stage compressor 6 is smaller than the intake amount of the first stage compressor 4 button and the second stage compressor 5 by an amount determined by the target compression ratio. The air is compressed to the desired pressure and then discharged.

The situation of volume change between compressors will be explained with reference to FIG.

In other words, two adjacent vanes 31.3 of the first stage compressor 4
1, the rotor 21, the case 11, and the casing 11 is at its maximum when the rotation angle of the drive shaft 9 is 0 (reference), and as the rotation angle increases, the volume changes as shown by the dotted line in Fig. 4. and compressed.

Further, the space volume surrounded by the two adjacent vanes 32, 32, the rotor 22, and the casing 12 of the second stage compressor 5 is minimum when the rotation angle of the drive shaft 9 is 0,
As the rotation angle increases, the volume changes as shown in the area surrounded by the solid line and dotted line in FIG.

On the other hand, the intermediate discharge ports D11 and Dl of the first stage compressor 4
2. D13D14 and intermediate suction port S21 of the second stage compressor 5
゜822, S23, and S24 are pipe group P11, respectively.
Since they are connected by ゜PI 2 , Pl3, and P14, their total volume changes as shown by the solid line in FIG. 4.

Therefore, it is compressed as a whole, and the suction port S of the first stage compressor 4 is
The entire amount of air taken in from the second stage compressor 5 is transferred to the intermediate discharge port D21. D22D23. It is discharged from D24.

The compressed air exchange relationship between the second stage compressor 5 and the third stage compressor 6 is also exactly the same as described above.

Compression is generally performed relatively slowly, so that the pressure difference on both sides of the bay 73 is not large, reducing wear and friction losses.

Next, other effects will be explained using a PV diagram.

FIG. 1 is a PV diagram showing the total volume on the horizontal axis and the pressure at that time on the vertical axis.

The air sucked up to a point a by the first stage compressor 4 is sequentially compressed as the rotor 21 rotates, and is supplied to the second stage compressor 5 at each compression stage.

The change in volume and pressure at this time is originally a transition from a to b as shown by the dotted line in Figure 1, but as shown in Figure 3, it is cooled by the cooling device 7 installed midway. Therefore, as shown by the solid line in FIG. 1, there is a transition from a to b'.

The required power required to compress air in this way is represented by the area surrounded by d-a-b-c in the former case and d-ab'-c in the latter case.

In the compression device according to the invention, during each compression stage, the air flowing through the husband's pipe is cooled by the cooling device 7, so that the power consumption can be significantly reduced, as is clear from FIG.

By installing multiple stages of compressors and cooling devices that have this effect, it is possible to achieve even gentler compression, which brings it closer to ideal isothermal compression. This will be further explained based on FIG. 5 in comparison with the conventional example.

In conventional two-stage compression, the required power when the discharge port of the first stage compressor and the suction port of the second stage compressor are simply connected is a -
It is expressed as the area enclosed by b - cd - e, which is typical adiabatic compression.

In addition, in conventional two-stage compression, if the discharge port of the first stage compressor and the suction port of the second stage compressor are simply connected and a cooling device is installed between them, the required power is a-b-b' - c'-d-
It can be seen that the power consumption can be reduced slightly compared to the former case, which is expressed by the area surrounded by e.

In contrast, the compression device according to the present invention has an intermediate discharge port connected to each compression stage of the first stage compressor, and a corresponding second discharge port.
The compressed air is cooled by connecting the intermediate suction ports of the stage compressors with respective pipes, and by interposing these pipe groups in a cooling device.

Therefore, the required power is expressed by the area surrounded by a-b'C''-d-e, and it is clear that the power consumption can be significantly reduced compared to the former two.

The details of the cooling device will be explained based on FIG.

Since the compressed air for each compression stage compressed by the first stage compressor 4 in FIG. 3 has a different compression ratio,
Of course, the temperature also matters.

That is, the compressed air discharged from the intermediate discharge port D11 is close to room temperature, but the compression ratio of the compressed air discharged from Dl 2 , Dl 3 , and Di 4 gradually increases. The temperature of the compressed air flowing inside 4 also rises.

Therefore, pipe P11, which is close to room temperature, is installed at the bottom, and pipe P12. If Pl3 and then Pl4 are installed at the top, cold water is supplied from the lower water supply port 51, and water is drained from the upper drain port 52, the cooling effect can be increased.

The above explanation is for a vane-type compressor in which multiple compressors share a common drive shaft, that is, a device in which the rotors of multiple compressors all rotate at the same rotation speed. A vane type compression device in which a plurality of compressors have different rotational speeds will be described below.

In a compression device configured so that the rotational speed of multiple compressors is the same, the discharge amount of the n-th stage compressor (n is an integer, the same applies hereinafter) is the same as that of the (n-1) stage compressor. As mentioned above, the intake amount must be set to be smaller than the intake amount by an amount determined by the target compression ratio.

In other words, the purpose could not be achieved unless the compressors from the first stage to the final stage were all constructed with different capacities.

However, in the case of the compression device described here in which a plurality of compressors have different rotational speeds, it is not necessarily necessary to make the capacities of the compressors different from the first stage to the final stage.
Even if compressors of the same capacity are used, the purpose can be sufficiently achieved.

In other words, when compressors of the same capacity are used, the (n-th
i) The objective can be achieved by rotating the stage compressor at a revolution speed corresponding to the target compression ratio of the n-th stage compressor.

Being able to use compressors of the same capacity in this way is extremely convenient in terms of replacement of consumable parts and preventive maintenance.

Furthermore, as a method for making the rotational speeds of a plurality of compressors different, it is also possible to use a plurality of transmission devices for one drive source, or to install a plurality of one drive source.

The compressor installed in the vane type compression device described above is intended for the diametrical slider type compressor shown in Fig. 2, but is not limited to this. Even better effects can be expected by using the axial slider type compressor shown in the figure.

Next, other embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 7 shows the configuration of an axial sliding device type multi-stage compressor 53, and FIGS. 8 to 10 similarly show cross-sections of essential parts.

The multi-stage compressor 53 is composed of a plurality of vane-shaped working chambers from the first stage to the final stage (two stages in Figs. 7 to 10), and the first stage working chamber 54 has an inlet 'SO'. , each of the final stage working chambers 55 is provided with one discharge port DO.

The first stage working chamber 54 has intermediate discharge ports D11, Dl2°Dl3. Dl4, and the final stage working chamber 55 has an intermediate suction port S21. S22,823. It is equipped with S24.

A vane 3a is always interposed between these mutually adjacent intermediate discharge ports and intermediate suction ports, and the intermediate discharge port D
11, DI 2°Dl3. Between Dl4 and the corresponding intermediate suction ports S21°822, S23, S24 are pipe groups P11, P interposed in the cooling device 7, respectively.
l2. Connected by Pl 3° Pl4.

Further, the compressor 53 is connected to a drive device (not shown) via a drive shaft 9 so as to be rotatable.

The effects of the vane type compression device having the above configuration will be explained.

First, when the drive shaft 9 makes the eighth rotation and rotates in the direction of the arrow shown in FIG. 10, the rotor 2a also rotates in the direction of the arrow.

Therefore, the vane 3a attached to the rotor 2a is connected to the cam 56 of the first stage working chamber 54 and the cam 57 of the final stage working chamber 55.
It rotates while sliding in the axial direction in close contact with each other.

In the first stage working chamber 54, air is sucked in through the suction port SO and compressed sequentially, and the air in the process of being compressed flows through the intermediate discharge ports D11, Dl2, and Dl3.

It is sequentially discharged from Dl4.

The air discharged from these discharge ports is piped into each pipe P11.
, Pl 2. The intermediate suction port 821 of the final stage working chamber 55 is cooled by the cooling device 7 which passes through Pl3°Pl4.
822.

The process is guided to S23 and S24.

At this time, intermediate discharge ports D11 and Dl2 of the first stage working chamber 54
, Dl2 and Dl3, and between Dl3 and Dl4, since the vane 3a is always interposed, air having different compression ratios is discharged.

This air with a different compression ratio is supplied to the intermediate suction ports S21, 822°S23, 824 of the final stage working chamber 55, and the pressure is increased to 1 again.
The compressed air is compressed and discharged from the discharge port DO at a desired pressure.

In this way, the compressed air having different compression ratios is independently guided from the first stage working chamber 54 to the pipe and passes through the cooling device 7 on the way, so that the cooling effect can be further improved.

In Figures 7 to 10, two stages of working chambers and one cooling device are used, but by further increasing the number of working chambers and cooling devices, it is possible to perform compression that closely approximates ideal isothermal compression. It is something.

Here, the discharge amount of the final stage working chamber 55 is set to be smaller than the suction amount of the first stage working chamber 54 by an amount determined by the target compression ratio, so the air is compressed to the target pressure. It is discharged.

In FIGS. 7 to 10, air is compressed using axially sliding vane-type multi-stage compression chambers, so the compression device itself can be made extremely compact.

Furthermore, it goes without saying that the operating chambers 58 and 59, which are excluded from the explanation in FIG. 7, can be effectively used as the third-stage button and the fourth-stage operating chamber by appropriately selecting their spatial volumes.

Further, although FIGS. 7 to 10 show a configuration in which air is compressed by a multi-stage working chamber of the axially sliding blade type, the configuration is not limited to this, and a diametrically sliding blade as shown in FIG. 11 is used. The same objective can also be achieved with a compression device constructed by a type of parallel multi-stage compressor.

As is clear from the above description, the vane type gas compression device according to the present invention has novel functions not found in conventional products, and has many excellent effects as described below.

(1) Compressed gas having a different compression ratio for each compression stage is guided from the intermediate discharge port to the corresponding intermediate suction port, so the flow of the compressed gas is extremely smooth.

(2) The pipe group leading from the intermediate discharge port to the intermediate suction port is
The compressed gas is effectively cooled because it is interposed with a cooling device.

(3) Since independent gas compression is repeated for each compression stage, gentle compression is possible and it is possible to approach ideal isothermal compression.

(4) Since the pressure difference between both sides of the vane becomes smaller, wear and friction loss are reduced.

(5) Power consumption for compressing gas can be significantly reduced.

(6) Since compression is performed in multiple stages, the difference in flow rate between each compression stage is small, and the cooling effect is significantly increased.

(7) The compressed gas discharged in the final stage is cooled and has no temperature rise.

(8) There is no need to cool the lubricating oil.

(9) The structure is simple, small, and lightweight.

00) Fewer breakdowns and easy maintenance management.

01) Low manufacturing cost and long life.

The vane type gas compression device of the present invention, which has many excellent advantages as described above, can be applied to various technical fields to obtain remarkable effects.

[Brief explanation of drawings]

1st freezing and 5th figure are l''V diagrams, 2nd figure is a sectional view of the main part of a conventional compressor, 3rd figure is an explanatory view of the main part showing the embodiment of the present invention, and 4th figure is a compressor. 6 is a longitudinal cross-sectional view of the cooling device, FIG. 7 is a longitudinal cross-sectional view of the axially sliding compressor, FIG. 8 is a cross-sectional view taken along line XX in FIG. 7, and FIG. The figure is a YY sectional view of FIG. 8, FIG. 10 is a Z-X sectional view of FIG. 7, and FIG. ...Casing, 2...Rotor,
3... Vane, 4, 5, 6, 53...
Compressor, 7, 8... Cooling device, 9...
Drive shaft, 10... Drive device, 54.55...
...Working chamber, D...Discharge port, S...
Inlet, P...pipe.

Claims (1)

[Scope of Claims] 1 A plurality of vane type compressors constituting the first stage to the final stage are arranged, and the first stage compressor has one suction port, and the final stage compressor has one discharge port. The n-th stage compressor has a plurality of intermediate discharge ports, and the (n+i)th membrane compressor has a plurality of intermediate suction ports (n is an integer of 1, 2, etc.), and they are adjacent to each other. One or more vanes are always interposed between the intermediate discharge ports and between the intermediate suction ports, and between the intermediate discharge ports and the corresponding intermediate suction ports, a group of pipes each interposed in a cooling device is provided. A vane type gas compression device, characterized in that the compressor is connected to a drive device. 2. A vane type gas compression device according to claim 1, wherein the plurality of compressors have different rotational speeds. 3. A vane type gas compression device, which is the same as the compression device according to claim 1, and is characterized in that a plurality of compressors share a common drive shaft. 4. A vane-type gas compression device, characterized in that the compressor according to any one of claims 1 to 3 has an axially sliding blade type compressor. 5 A multi-stage compressor is provided with a plurality of vane-type working chambers constituting the first stage to the final stage, and the first stage working chamber has one suction port and the final stage working chamber has one discharge port. Provide at least one
The nth stage working chamber is provided with a plurality of intermediate discharge ports, and the (n+1)th membrane working chamber is provided with a plurality of intermediate suction ports (n is an integer of 1, 2, etc.), and the intermediate suction ports are adjacent to each other. One or more vanes are always interposed between the intermediate button and the intermediate suction port, and the intermediate discharge port and the corresponding intermediate suction port are connected by a group of pipes each interposed in a cooling device, A vane type gas compression device, wherein the compressor is connected to a drive device. 6. A vane-type gas compression device, which is an addition to the compression device according to claim 5, wherein the compressor has an axially sliding blade type.