JP5205041B2 - air compressor - Google Patents

Description

  The present invention relates to an air compressor.

  One of the factors affecting the performance of the air compressor is the state of intake air immediately before compression. The intake air temperature is the same as the ambient temperature of the compressor, and it is desirable that the pressure be sucked in at atmospheric pressure, so a package type compressor with a soundproof cover is provided with a dedicated intake duct, etc. It has a structure that sucks air directly from the outside of the compressor package which is not easily affected by As a result, the intake air causes a pressure loss in the intake duct in addition to the intake filter and the intake valve, which causes a reduction in the performance of the compressor.

  In addition, the number of openings provided in the soundproof cover of the compressor increases and the noise radiated to the outside of the machine increases, so as a noise countermeasure, the noise is confined and reduced by complicating the shape of the intake duct. In many cases, however, this method conversely increases the pressure loss in the intake duct portion and further degrades the performance of the compressor body.

  Another method is to provide a suction port for the compression air inside the compressor package to reduce the pressure loss and noise of the suction duct. In this case, the temperature of the intake air is affected by the heat generated by the compressor body. As it rises, the density of air is lowered, which may lead to a decrease in the performance of the compressor.

  As a conventional technique for improving the performance of the screw compressor with respect to such a problem, there is an example disclosed in Patent Document 1. In this example, noise is reduced by partitioning the drive part in the package with a partition, and the discharge air volume is increased and the discharge temperature is decreased by taking into consideration the flow of air supplied to the compressor body and cooling air. I am trying.

JP-A-7-279877

  In the above-mentioned Patent Document 1, a noise generation source is provided with a partition wall that partitions a space A in which a compressor body and a motor are arranged and a space B in which a fan and an oil cooler are arranged to reduce noise. . The air sucked from the air inlet of the package is guided to the space A through the duct by the fan, and is also branched and sent to the oil cooler disposed in the space B.

  The air sent to the space A through the duct is sucked into the compressor body and also cools the motor, and the air after motor cooling is sent out of the package from the first air outlet. The air after cooling the oil cooler is sent out of the package from the second air outlet of the space B.

  Since the compressor body sucks in ambient air by driving the motor, in the configuration of Patent Document 1, air sent to the space A through the duct is sucked into the compressor body through the suction filter. At this time, the air suction amount depends on the rotational speed of the compressor body. Therefore, even if the intake air amount of the compressor main body is large, if the air amount necessary for cooling the motor is not excessively sucked, the cooling of the motor and the compressor main body are affected.

  Moreover, in patent document 1, although the motor is arrange | positioned below the opening of the duct in the space A, since the 1st air outlet is arrange | positioned upwards (refer FIGS. 1-4), it is for cooling. It becomes difficult to sufficiently supply air to the motor. In particular, since the air sent by the fan branches after passing through a long duct, in the space A, it is difficult to obtain the air blowing effect by the fan.

  Therefore, in order to cool the space A in the route to the upper first air outlet after cooling the motor arranged below, it is considered that a structure that reduces the pressure loss of the route is necessary. There is a problem that the structure inside the space becomes complicated.

  In this example, the package requires an air outlet after cooling the oil cooler (second air outlet), and is provided with three openings, an air inlet, a first air outlet, and a second air outlet. Becomes easy to leak out. Actually, if the sound insulation plate is not provided at the first air outlet as in Patent Document 1, it is difficult to obtain a noise reduction effect, and as a result, the number of parts is increased for sound insulation.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an air compressor that achieves performance improvement and noise reduction while having a simple configuration.

In order to achieve the above object, in this gun onset Ming,
A compressor body that compresses air, a motor that drives the compressor body, an after cooler that cools the compressed air compressed by the compressor body, and a cooling that blows air to the after cooler and cools the compressed air In an air-cooled air compressor with a fan in the package,
An intake opening that is provided in the package and communicates with outside air; an intake opening that is provided in the package and is located downstream of the cooling fan and communicates with the compressor body; and An exhaust opening for exhausting the air after cooling the aftercooler provided to the outside,
The motor is disposed between the cooling fan and the intake opening, and the aftercooler is disposed between the cooling fan and the exhaust opening and blown by the cooling fan. Air is sent to the compressor body through the suction opening,
A fan motor that drives the cooling fan , and a booster that uses a power source together with the fan motor to increase the pressure of the air sent to the compressor body, the fan motor being an operation switch for the air compressor Rotate with the motor .

  ADVANTAGE OF THE INVENTION According to this invention, although it is a simple structure, the air compressor which aimed at the performance improvement and noise reduction can be provided.

  An embodiment of an air compressor according to the present invention will be described with reference to an oil supply type screw compressor shown in FIGS. 1, 2, 3, and 4. FIG. 1 is a system diagram of an oil supply type screw compressor according to a first example of the present embodiment.

  This oil supply type screw compressor compresses the intake air that has passed through the suction filter 1 and the suction valve 2 to a predetermined pressure by the compressor main body 3, and the compressor main body 3 includes a pair of screw rotors therein. Yes. The compressor body 3 is driven by a motor 4 that is rotated by being supplied with electric power from an electric box (not shown) on which a compressor control board is mounted.

  The compressed air compressed by the compressor body 3 passes through the piping, and the oil component is separated in the oil separator 5. Then, after oil is removed by the oil separator 5, the oil is cooled by the aftercooler 6, passes through a dryer (not shown), and then supplied from the discharge pipe 8 to the external equipment.

  On the other hand, the circulating oil is discharged from the discharge port together with the air compressed by the compressor body 3, separated from the compressed air by the oil separator 5, and then cooled by the oil cooler 7. Then, after passing through an oil filter (not shown) or the like, it is supplied to the compressor body 3. Thus, the lubricating oil is configured to circulate in the circulation path as the compressor is operated.

  The air for cooling the aftercooler 6 and the oil cooler 7 passes through a path different from the path of the intake air to the compressor body 3, and after exchanging heat with the aftercooler 7 and the oil cooler 8, the outside of the compressor Is discharged. Specifically, it is provided with a fan motor 10 and a cooling fan 11 and is an air-cooling type that performs cooling. Each of these components is disposed in the package 12, and the package 12 is provided with openings 12a and 12b serving as air inlets and outlets.

  When the screw compressor of this embodiment receives an operation signal from the operation switch, the motor 4 is started by an electric box (not shown), and the compressor main body 3 is driven to start air compression. Further, the electric box drives the fan motor 10 and rotates the cooling fan 11 to start blowing air, and starts heat exchange with the after cooler 6 and the oil cooler 7.

  At that time, the cooling fan 11 provided on the upstream side of the after cooler 6 and the oil cooler 7 increases the pressure of the cooling air, and the increased air is used as intake air and the cooling for heat exchange with the compressor body 3. It is supplied to the heat exchanger as wind. Here, in order to guide the air whose pressure has increased to the compressor body 3 as intake air, a suction opening 9 communicating with the compressor body 3 is provided on the downstream side of the cooling fan 11.

  The arrangement of the components related to the air flow at this time will be described with reference to FIG. FIG. 2 is a diagram showing the flow of air in the present embodiment, and since the premise configuration is the same as that in FIG. 1, the reference numerals are omitted. By the operation of the compressor body 3 or the cooling fan 11, air is taken in from the opening 12a for intake. The motor 4 is disposed between the opening 12a and the cooling fan 11, and the motor 4 is cooled by the air taken in from the opening 12a.

  Thereafter, the air boosted by the cooling fan 11 cools the aftercooler 6 and the oil cooler 7, and is exhausted from the exhaust opening 12b to the outside of the compressor. A part of the pressurized air is sent to the compressor body 3 through the suction opening 9. Therefore, the air whose pressure has been increased by the cooling fan 11 is substantially unchanged from the atmospheric temperature and is supplied to the compressor body 3 in a state higher than the atmospheric pressure. As a result, the pressure loss of the intake air is reduced and the performance of the compressor body 3 is improved, so that it is possible to increase the amount of discharged air or reduce the power consumption.

  In addition, it is easy to simplify the air path from the cooling fan 11 through the coolers 6 and 7 to exhaust from the opening 12b, and the performance of the entire compressor can be improved with a simple configuration.

  In addition, in the structure in which air is directly sucked from the outside of the package via an intake duct or the like, noise generated during the suction is radiated from the suction duct and leaks to the outside of the compressor, whereas in the structure of this embodiment, the cooling fan 11 Since noise generated from the air and noise generated when air is sucked can be combined into one, the noise can be easily controlled, and the noise can be reduced.

  Thus, according to the said structure, the freedom degree of arrangement | positioning of the motor 4 used as a sound source with the simple structure, the cooling fan 11, the fan motor 10, the air intake opening 9, and the compressor main body 3 can be raised. In addition, the package 12 has a function as a soundproof cover, and the opening provided in the package 12 can be made into two openings, an intake opening 12a and an exhaust opening 12b. The noise reduction effect can be enhanced as compared with the above.

  Further, since the motor 4 is arranged at the most upstream position in the air flow in the package 12, the motor 4 is operated at a position where the temperature is maintained at substantially the same level as the outside air. Therefore, even when the ambient temperature around the compressor is high, the motor 4 is cooled in a place where it is difficult to be affected by other heat generating parts, so that reliability can be improved.

  Next, a second embodiment will be described with reference to FIG. Note that description of parts common to the first embodiment is omitted. FIG. 3 is a system diagram of the screw compressor of the second embodiment. In this embodiment, a booster device having both a fan motor 10 and a power source is provided, and the pressure of air sent to the compressor body 3 is increased using this booster device. Here, an example in which the dedicated fan 14 and the casing are used as a booster will be described.

  On the opposite side of the cooling fan 11 and the double-shaft motor 13 that drives the cooling fan 11, a dedicated fan 14 and a casing for sending air to the compressor body are provided. The shaft motor 13 is started. Air is supplied to the aftercooler 6 and the oil cooler 7 by the cooling fan 11, and at the same time, the pressure is increased by the dedicated fan 14 and the casing. The air whose pressure has risen is supplied to the compressor main body 3 through the dedicated duct almost at the same temperature as the atmospheric temperature and higher than the atmospheric pressure.

  According to the present embodiment, the dedicated fan 14 and the casing are required, but it is supplied to the compressor main body 3 in a state that is surely higher than the atmospheric pressure than the first embodiment. As a result, the pressure loss of the intake air is reduced and the performance of the compressor body 3 is improved, so that it is possible to increase the discharge air amount or reduce the power consumption.

  Next, a third embodiment will be described with reference to FIG. Note that a description of portions common to the first and second embodiments is omitted. FIG. 4 is a system diagram of the screw compressor of the third embodiment. This embodiment shows a configuration including means for converting the energy of the compressed air compressed by the compressor body 3 into an increase in the pressure of the intake air.

  The air compressed together with oil in the compressor body 3 is separated into compressed air and circulating oil by the oil separator 5, and the compressed air passes through the aftercooler 6 and the dryer (not shown) and is connected to the outside of the compressor. Supplied to each facility. Compressed air energy is used in the air piping path in the compressor, and the air whose pressure is increased to a state higher than the atmospheric pressure is supplied to the compressor main body 3 by the device 15 that is driven by the energy and raises the pressure of the intake air. Is done. In this case, the present invention can also be applied to a water-cooled screw compressor that does not include a large cooling fan installed in the air-cooled screw compressor.

  4 shows a structure provided with a device 15 for raising the pressure of the intake air between the oil separator 5 and the aftercooler 6, this device 15 is a discharge pipe downstream of the aftercooler. You can be in the middle of 8.

  According to this embodiment, since energy of compressed air is used, the present invention can be applied not only to the air cooling type but also to other compressors without increasing the size of the cooling fan and the fan motor. For example, even with a water-cooled compressor, the pressure of the intake air can be increased by the energy of the compressed air without using the cooling fan 11.

  Further, it is supplied to the compressor main body in a state that is surely higher than the atmospheric pressure as compared with the first and second embodiments. As a result, the pressure loss of the intake air is reduced and the performance of the compressor body is improved, so that it is possible to increase the discharge air amount or reduce the power consumption.

  Furthermore, since the pressure increasing effect in the air suction into the compressor body 3 is obtained separately from the fan motor 10, the degree of freedom of arrangement of the fan motor 10 is improved, and the performance is improved and the noise is reduced with a simpler configuration. Can be obtained.

  According to each of the above embodiments, since the intake air immediately before compression is substantially the same as the atmospheric temperature and can be supplied to the compression body in a state higher than the atmospheric pressure, the pressure loss caused by the intake filter or the like can be reduced, and the compressor discharge An increase in the amount of air or power consumption can be reduced.

  Further, as shown in the above embodiments, the motor 4 is arranged on the upstream side of the air flow, so that the cooling of the motor 4 can be made less susceptible to the suction of the compressor body 3, and the cooling object and the fan In this arrangement, the configuration can be simplified, and the effectiveness of performance improvement can be enhanced.

The system diagram of the oil supply type screw compressor which concerns on a 1st Example. The figure which shows the flow of the air in a 1st Example. The system diagram of the oil supply type screw compressor which concerns on a 2nd Example. The system diagram of the oil supply type screw compressor which concerns on a 3rd Example.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Suction filter, 2 ... Suction valve, 3 ... Compressor body, 4 ... Drive motor, 5 ... Oil separator, 6 ... After cooler, 7 ... Oil cooler, 8 ... Discharge piping, 9 ... Suction opening, 10 ... Fan motor, 11 ... cooling fan, 12 ... package, 13 ... double-axis fan motor, 14 ... dedicated fan, 15 ... pressure raising device.

Claims (1)

A compressor body that compresses air, a motor that drives the compressor body, an after cooler that cools the compressed air compressed by the compressor body, and a cooling that blows air to the after cooler and cools the compressed air In an air-cooled air compressor with a fan in the package,
An intake opening that is provided in the package and communicates with outside air; an intake opening that is provided in the package and is located downstream of the cooling fan and communicates with the compressor body; and An exhaust opening for exhausting the air after cooling the aftercooler provided to the outside,
The motor is disposed between the cooling fan and the intake opening; the aftercooler is disposed between the cooling fan and the exhaust opening;
Air blown by the cooling fan is sent to the compressor body through the suction opening,
A fan motor that drives the cooling fan, and a booster that uses a power source together with the fan motor to increase the pressure of the air sent to the compressor body, the fan motor being an operation switch for the air compressor The air compressor rotates together with the motor.

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