JP3732031B2 - air compressor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an air compressor that sucks and compresses air in the atmosphere.
[0002]
[Prior art]
Conventionally, air compressors are widely used in various fields. And basically, this air compressor takes air in the atmosphere through an air filter into the suction flow path connected to the suction port of the compressor body, and compresses this air in the compressor body, It forms so that it may discharge from the discharge port of a compressor main body.
[0003]
[Problems to be solved by the invention]
In the case of the conventional air compressor, when the temperature of the air sucked from the suction port, that is, the suction temperature is increased, the density of the sucked air is decreased. For this reason, there is a problem that the amount of air discharged from the compressor body per unit power is reduced by that amount, and the power consumption is increased.
The present invention has been made to eliminate such a conventional problem, and an object of the present invention is to provide an air compressor capable of reducing power consumption.
[0004]
[Means for Solving the Problems]
In order to solve the above-described problems, the present invention provides an intake cooling means interposed in a suction flow path that guides air taken from the atmosphere to a suction port of a compressor body for air, and a discharge flow path of the compressor body for air. Includes an aftercooler, a reheater, a sixth heat exchanger for evaporation, and a drain trap, and the sixth heat exchanger includes a compressor main body for refrigerant, a fourth heat exchanger for refrigerant condensation, and an expansion valve. And the first flow rate control valve together with the first flow rate control valve to form a refrigerant third circulation path. The refrigerant compressor body and the fourth heat exchanger serve to evaporate the refrigerant. A refrigerant fourth circulation path is formed together with the seventh heat exchanger, the intake air cooling means is the seventh heat exchanger, and the compressed air discharged from the air compressor body is the aftercooler. To the reheater, the sixth heat exchanger, and the drain trap. After spent, fed out of the machine again passed through the reheater, the compressed air the discharge is first cooled in the aftercooler, the compressed air that has passed through the de Len trap the reheater Heat exchange is performed to raise the temperature of the compressed air, and the sixth heat exchanger cools it. The drain trap removes moisture, and the seventh heat exchanger sucks in the refrigerant. It was set as the structure which performs heat exchange between air .
[0005]
DETAILED DESCRIPTION OF THE INVENTION
Next, an embodiment of the present invention will be described with reference to the drawings.
Figure 1 shows an air compressor according to the first exemplary embodiment comprising a portion of the components of the implementation of the invention described below, the suction passage 2 to the suction port of the air compressor main body 1, discharge port The discharge flow path 3 is connected to this.
The suction flow path 2 is provided with an air filter 4, a first heat exchanger 5 that is an intake air cooling means, and a drain trap 6.
Then, air in the atmosphere is taken into the suction flow path 2 through the air filter 4 and cooled by the first heat exchanger 5 as will be described later, and the drained precipitate is separated and discharged by the drain trap 6. The cooled air is compressed by the compressor body 1 and discharged from the discharge port to the discharge flow path 3.
[0006]
The first heat exchanger 5 constitutes a part of the air compressor and a part of the refrigeration apparatus. This refrigeration apparatus includes a refrigerant first circulation path 14 including a refrigerant compressor body 11, a water-cooled second heat exchanger 12 for refrigerant condensation, an expansion valve 13, and a first heat exchanger 5 for refrigerant evaporation. Forming. Then, the refrigerant compressed by the refrigerant compressor body 11 is deprived of heat by heat exchange with the cooling water in the second heat exchanger 12 to be condensed into a high-pressure refrigerant liquid. And inflated. Further, this refrigerant liquid evaporates by exchanging heat with the air taken into the suction flow path 2 via the air filter 4 in the first heat exchanger 5, and the heat in the suction flow path 2 in the suction flow path 2 is evaporated. Cool the air.
[0007]
Thus, in this air compressor, since the air sucked into the compressor body 1 is cooled and the suction temperature is lowered, the air density is increased and the amount of discharge air per unit power is increased. To do. For example, when the atmospheric temperature is 30 ° C. and the suction temperature is set to 10 ° C. by cooling by the first heat exchanger 5, the discharge air volume increases by 7% as compared with the case where it is not cooled.
Further, when the compressor body 1 is an oil-cooled type in which lubricating oil is injected into a rotor chamber that performs air compression, the temperature of the compressed air discharged from the compressor body 1, that is, the discharge temperature, when the suction temperature decreases. As a result, the viscosity of the lubricating oil increases, so that the sealing performance of the rotor chamber is improved, the efficiency of air compression of the compressor body 1 is improved, and the discharge air volume is further increased.
[0008]
Further, when the compressor main body 1 is an oil-cooled type in which lubricating oil is injected into the rotor chamber, when the suction temperature decreases and the discharge temperature decreases, the temperature of the lubricating oil also decreases. As a result of the lowering of the lubrication temperature, the problem that the sucked air is warmed and thermally expanded and the density is reduced, that is, the problem of suction heating is solved to some extent, thereby increasing the air density and further increasing the discharge air volume. To do.
This discharge air volume increases by several tens of percent compared to our conventional machine, so even if considering that the increase in power consumption by the first heat exchanger 5 is several percent, the overall consumption is about 10%. Power can be saved.
Further, when the discharge temperature decreases, the aftercooler conventionally provided in the discharge flow path 3 of the compressor body 1 can be reduced in size or omitted.
[0009]
2, the illustrated air compressor according to a second reference example including a portion in common with the air compressor according to the first reference example part of the components of the implementation form of the present invention to be described later, The same numbers are assigned to each other and description thereof is omitted.
In this air compressor, an air-cooled aftercooler 21, a reheater 22, a third heat exchanger 23, and a drain trap 6 are interposed in the discharge flow path 3 of the air compressor body 1, and the third heat The exchanger 23 includes the refrigerant compressor body 11, the water-cooled fourth heat exchanger 24 for condensing the refrigerant, the expansion valve 13, and the fifth heat exchanger 25 for evaporating the refrigerant. Is forming. 2 functions as a dryer for drying the compressed air, while the fifth heat exchanger 25 is also an intake air cooling means in the suction flow path 2.
In addition, the * mark in FIG. 2 means that it is continuous.
[0010]
Specifically, as in the case of the first reference example, the refrigerant liquid that has passed through the expansion valve 13 exchanges heat with the air in the suction flow path 2 in the fifth heat exchanger 25 and partially evaporates. At the same time, this air is cooled. The compressed air discharged from the compressor main body 1 is first cooled by the aftercooler 21, exchanged heat with the compressed air that has passed through the drain trap 6 of the discharge flow path 3 by the reheater 22, and has passed through this. The temperature of the compressed air is increased, and the compressed air is cooled to reach the third heat exchanger 23. In the third heat exchanger 23, the refrigerant evaporates and the compressed air is cooled by the heat exchange between the compressed air and the partially evaporated refrigerant, and the precipitated water is separated by the drain trap 6. Then, the compressed air is in a dry state, and as described above, the temperature is raised by the reheater 22 and is further dried to be sent out of the apparatus.
[0011]
With such a configuration, the suction temperature is lowered, the discharge air volume is increased, the power consumption is reduced, and the aftercooler 21 can be reduced in size as in the case of the first reference example. Yes. In FIG. 2, the aftercooler 21 is provided. However, the aftercooler 21 can be omitted by providing the fifth heat exchanger 26.
Further, by cooling the intake air and removing the drain deposited in the suction flow path, it is possible to omit the drying operation or shorten the operation time in the discharge flow path.
[0012]
Figure 3 shows an air compressor according to the implementation embodiments of the present invention, portions common to the air compressor according to the above Reference Examples, the description thereof is omitted given the same number to each other.
In this air compressor, an air-cooled aftercooler 21, a reheater 22, a sixth heat exchanger 31, and a drain trap 6 are interposed in the discharge flow path 3 of the air compressor body 1. On the other hand, the refrigerant flow path is divided into two hands on the secondary side of the expansion valve 13, one of which is the refrigerant compressor body 11, the water-cooled fourth heat exchanger 24 for refrigerant condensation, the expansion valve 13, A part of the third refrigerant circulation path 33 of the refrigeration apparatus including the one flow rate adjusting valve 32 and the sixth heat exchanger 31 for refrigerant evaporation is formed. And the part enclosed with the dashed-dotted line B in FIG. 3 functions as a dryer for drying compressed air.
The other of the two refrigerant flow paths is the refrigerant compressor body 11, the water-cooled fourth heat exchanger 24 for condensing the refrigerant, the expansion valve 13, the second flow rate adjusting valve 34, and the refrigerant evaporation. A part of the refrigerant fourth circulation path 36 of the refrigeration apparatus including the seventh heat exchanger 35 is formed. The seventh heat exchanger 35 is also an intake air cooling means in the suction flow path 2.
As described above, the asterisks in FIG. 3 mean that they are continuous.
Then, in the device according to the implementation form of this, the amount of refrigerant flowing through the third circulation path 33 and the fourth circulating path 36 by adjusting the respective opening of the first flow control valve 32 and the second flow rate control valve 34 It is possible to adjust the functions of the intake air cooling and the dryer. Instead of the first flow rate adjustment valve 32 and the second flow rate adjustment valve 34, a three-way switching valve is provided at the branch portion of the refrigerant flow path on the secondary side of the expansion valve 13 to adjust the amount of refrigerant guided to each circulation path. You may make it do.
Further, similarly to the above, with such a configuration, the suction temperature is reduced, the discharge air volume is increased, the power consumption is reduced, and the aftercooler 21 can be miniaturized. In FIG. 2, the aftercooler 21 is provided, but the aftercooler 21 may be omitted by providing the seventh heat exchanger 35.
[0014]
In each reference example and embodiment described above, the heat of vaporization of the refrigerant in the refrigeration apparatus is used for intake air cooling. However, the present invention is not limited to this, and the first heat exchanger 5, Instead of the fifth heat exchanger 25 and the seventh heat exchanger 35, a compressor provided with an air-cooled or water-cooled heat exchanger is also included.
An air-cooled heat exchanger may be provided in place of the water-cooled fourth heat exchanger 24, and a water-cooled after-cooler may be provided in place of the air-cooled after-cooler 21, both of which are included in the present invention. included.
Furthermore, the compressor main body in the present invention may be either an oil-free type or an oil-cooled type. When the compressor main body is an oil-cooled type, as is well known, the discharge side of the compressor main body In addition, an oil separation / recovery unit is provided, and further, an oil supply flow path is provided from the lower part through an oil cooler and an oil filter to an oil injection point in the compressor body.
[0015]
【The invention's effect】
As apparent from the above description, according to the present invention, the intake air of the compressor is cooled, so that the intake temperature is reduced, the discharge air volume is increased, and the power consumption is reduced. The aftercooler that is normally provided can be downsized or omitted.
In addition, by using the refrigerant of the dryer, which is an accessory device in the discharge flow path, for the intake air cooling, the structure can be simplified compared to the case where a new cooling medium is used for intake air cooling, By making it possible to adjust the amount of refrigerant flowing to each of the dryer sides, there is also an effect that the suction temperature can be adjusted to the optimum according to the outside air temperature.
[Brief description of the drawings]
FIG. 1 is a diagram showing an overall configuration of an air compressor according to a first reference example of the present invention.
FIG. 2 is a diagram showing an overall configuration of an air compressor according to a second reference example of the present invention.
3 is a diagram showing the overall configuration of an air compressor according to the implementation embodiments of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Air compressor main body 2 Suction flow path 3 Discharge flow path 4 Air filter 5 1st heat exchanger 6 Drain trap 11 Refrigerant compressor main body 12 2nd heat exchanger 13 Expansion valve 14 Refrigerant 1st circulation path 21 After Cooler 22 Reheater 23 Third heat exchanger 24 Fourth heat exchanger 25 Fifth heat exchanger 26 Refrigerant second circulation path 31 Sixth heat exchanger 32 First flow control valve 33 Third circulation path 34 Second Flow control valve 35 7th heat exchanger 36 4th circulation path for refrigerant

Claims (1)

Intake air cooling means is interposed in the suction flow path that guides air taken from the atmosphere to the suction port of the compressor body for air ,
The discharge passage of the compressor body for air has an aftercooler, a reheater, a sixth heat exchanger for evaporation, and a drain trap,
The sixth heat exchanger forms a third circulation path for the refrigerant together with the refrigerant compressor body, the fourth heat exchanger for refrigerant condensation, the expansion valve, and the first flow control valve, and works for refrigerant evaporation,
The refrigerant compressor body and the fourth heat exchanger form a refrigerant fourth circulation path together with the second flow rate control valve and the refrigerant evaporation seventh heat exchanger,
The intake air cooling means is the seventh heat exchanger,
The compressed air discharged from the compressor body for air passes through the reheater, the sixth heat exchanger, and the drain trap in this order from the aftercooler, and then passes again through the reheater. Sent out of the machine
The discharged compressed air is first cooled by the aftercooler, heat exchanged with the compressed air that has passed through the drain trap by the reheater, the compressed air is heated, and the sixth heat exchanger While being cooled and the precipitated moisture is removed by the drain trap, it becomes dry,
An air compressor characterized in that heat is exchanged between the refrigerant and the intake air in the seventh heat exchanger.

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