JPH09264253A - Cooling structure of two step air cooling reciprocating compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve cooling performance, and carry out downsizing of a compressor main body by arranging an inter cooler and an after cooler in parallel with each other between the crank case and the fly wheel of a two step air cooling reciprocating compressor, and spraying cooling wind from the fly wheel faced to a cooler to both coolers. SOLUTION: Air compressed by the low pressure cylinder 1 of a two step air cooling reciprocating compressor is led to a high pressure cylinder 8 through an leading-in pipe 2, an inter cooler 3, and a water separator 7, and it is compressed in the high pressure cylinder 8 again. Compressed air is cooled by an after cooler 10 through a discharging pipe 9, and then it is discharged. In this case, the inter cooler 3 and the after cooler 10 are arranged between a fly wheel pulley 14 and a crank case 4 and in a pulley outer diameter position, and they are faced to each other on a position where almost of both coolers 3, 10 are covered. Cooling wind generated by rotation of the fly wheel pulley 14 makes flow to both coolers 3, 10, and thereby, compressed air is cooled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intercooler as an intercooler for a two-stage air-cooled reciprocating compressor, and an arrangement structure for attaching an aftercooler for cooling discharge air.

[0002]

2. Description of the Related Art A two-stage air-cooled reciprocating compressor is provided with an improved compression efficiency and a lubricating oil emulsification countermeasure in the case of an oil supply type compressor.
Generally, a structure including an intercooling mechanism and a water separator is provided in the middle of a pipeline for feeding air from the low pressure cylinder to the high pressure cylinder. And, in the structure of this intercooler, various forms exist, the basic is that an intercooler with a long conducting pipe with cooling fins is attached near the cylinder of the compressor, Cooling is performed along with cooling of the cylinder, and water condensed by cooling is removed by a water separator.

Further, the air discharged from the high-pressure cylinder is directly introduced into the air tank without providing an aftercooler, and is cooled while being stored in the air tank to separate water. When supplying dry air to other refrigeration air dryers, install an aftercooler separately from the compressor, cool it using a cooling fan dedicated to the aftercooler, and then introduce it into the refrigeration air dryer. The way to do is taken.

On the other hand, a package type reciprocating compressor in which the reciprocating compressor is housed in a soundproof box is a compressor that has rapidly spread in recent years. A package type compressor with a dryer, which is mounted on the package type reciprocating compressor and is integrated, has also come into standard mass production. In the package compressor with a dryer, the temperature of the air supplied to the refrigeration air dryer is lowered because it is necessary to mount a relatively small refrigeration air dryer. For this reason, an aftercooler and a separate cooling fan for the aftercooler are provided in the package and supplied to the refrigeration air dryer. These must be placed in a narrow package, which is a major factor in the high cost. Further, even in a package compressor that does not have a refrigeration air dryer, by installing an aftercooler, the air that efficiently cools the compressed air temperature is introduced into the air tank that is stored in the package. It has the effect of promptly separating water and reducing the temperature rise inside the package. Also, in the package type compressor,
When accommodating the intercooler and the aftercooler, the total volume of the package becomes large or the inside becomes complicated piping depending on the disposition, which requires assembling man-hours and becomes a problem of high cost.

[0005]

When an intercooler as an intercooler and an aftercooler for cooling discharge air are attached to a two-stage air-cooled reciprocating compressor,
The purpose is to use the cooling air from the flywheel pulley, which has the function of a cooling fan, effectively for the heat exchange of the intercooler and aftercooler, and to make the configuration of the compressor body with both coolers as compact as possible. It is what

[0006]

According to the present invention, an intercooler for intercooling compressed air is attached in the middle of a pipeline connecting a low pressure cylinder and a high pressure cylinder of a two-stage air-cooled reciprocating compressor.
Low-pressure air is supplied to the high-pressure side through a water separator that removes the drain water condensed and separated by the intercooler, and high-pressure air compressed and discharged by the high-pressure cylinder is introduced into the air tank in the middle of the pipeline. In a multi-cylinder two-stage air-cooled reciprocating compressor provided with a cooler, the intercooler and the aftercooler are arranged in parallel between a crankcase and a flywheel of the two-stage air-cooling reciprocating compressor, and both coolers are cranked. A cooling structure of a two-stage air-cooled reciprocating compressor, which is attached directly to the case and allows cooling air from a flywheel pulley having a function of a cooling fan facing the both coolers to flow through the both coolers for heat exchange. is there.

When the intercooler and the aftercooler are directly mounted in parallel on the crankcase of the two-stage air-cooled reciprocating compressor, the both coolers are directly mounted by directly mounting bolts and nuts on the legs of the crankcase. Installation,
Further, it is a cooling structure of the two-stage air-cooled reciprocating compressor in which both coolers are attached to the wall surface of the crankcase with a means for maintaining an appropriate interval.

[0008]

Operation: Main body set of two-stage air-cooled reciprocating compressor of the present invention Fig. 1
The operation will be described with reference to the front view of FIG.
The air discharged from the low pressure cylinder (1) by one-stage compression is
It is introduced into the intercooler (3) via the introduction pipe (2) and air-cooled. The intercooler (3) is fixed to the leg portion (4a) of the crankcase (4) by a plurality of bolts (17) and nuts (5). The air cooled by the intercooler (3) is introduced into the water separator (7) through the conduit tube (6), and the water in the air is condensed by the heat exchange of the intercooler to form water droplets. , Is separated by a water separator (7), and is discharged by an auto drain device attached to the lower part of the water separator. Cooling air from which water has been separated is supplied to the high-pressure cylinder (8), and two-stage compression is performed in the high-pressure cylinder (8). High pressure cylinder (8)
Air discharged from the is introduced into the aftercooler (10) via the discharge pipe (9). Aftercooler (10)
Are installed in parallel with the intercooler (3) in a symmetrical position with the crankshaft (11) as the center line. The aftercooler is fixed to the leg portion of the crankcase by a plurality of bolts (17) and nuts (12), like the intercooler. The air cooled by the aftercooler (10) is supplied from an outlet (13) to an air tank (not shown). When a refrigerating air dryer is used in a package compressor or the like, the air cooled and stored in the air tank is supplied to the refrigerating air dryer.

The air cooling operation in the above structure will be described with reference to FIG. A flywheel pulley (14) for driving a compressor is attached to the crankshaft (11). The flywheel pulley (14) is a flywheel pulley that also serves as a cooling fan and has a rib portion formed into a blade shape. The intercooler (3) and the aftercooler (10) are flywheel pulleys (14).
And a crankcase (4), and is attached so as to face the flywheel pulley (14). The positions where both coolers face each other are arranged in the pulley outer diameter position shown by the dotted line in FIG. 1 so that most of both coolers can be covered. The cooling air generated by the rotation of the flywheel pulley (14) flows from the lower part of the crankshaft (11) to both coolers (3) (10) to perform heat exchange. Then, the cooling air on the upper part of the crankshaft (11) cools the cylinder parts (1) and (8) as usual. The cover (15) is
The role of a guide plate for effectively cooling the cylinder part,
The cover (15) also serves as a danger prevention so that the cylinder head is not directly touched.

In the side view of FIG. 2, both coolers (3) (10) are shown.
When it is attached to the leg portion (4a) of the crankcase (4), it is attached with a proper distance from the side wall of the crankcase (4). This is provided in order to prevent the exhaust hot air that has undergone heat exchange in both coolers from raising the temperature of the crankcase (4), and according to experiments, it is in contact with or close to the crankcase wall surface. If both are installed, the air cooling effect of both coolers will be reduced, the temperature of the crankcase will rise, and the temperature of the lubricating oil in the crankcase will rise accordingly, lowering the viscosity of the lubricating oil more than necessary. This is due to the discovery of problems that reduce lubrication ability and increase oil rise.

With the above-described structure and operation, the aftercooler (10) is attached within the same size as the outer shape of the conventional two-stage air-cooled compressor, and by the cooling air of the cooling fan shared by the flywheel pulley (14), The heat exchange of both coolers (3) (10) is effectively performed, and the crankcase leg (4a) is
By attaching (3) and (10) to both coolers,
The cooling air from the flywheel pulley (14) is used in the lower half, which has relatively low utilization efficiency, so that the cooling effect of both cylinders (1) and (8) is not reduced,
The compressed air can be cooled by heat exchange between the coolers (3) and (10), and the effect of reducing the number of separate cooling fans that have conventionally used aftercoolers can be obtained. Also, when mounting on a package type reciprocating compressor,
Since the compressor main body is provided with the intercooler (3) and the aftercooler (10), it is not necessary to consider the position of arrangement of the aftercooler, so that the assembly is greatly simplified.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described in detail with reference to the drawings. However, the overlapping parts described in the section of the action will be omitted in principle. The embodiment of the present invention is an embodiment,
In a two-stage air-cooled reciprocating compressor that can be equipped with an intercooler and an aftercooler, it is also applied to a two-stage air-cooling reciprocating compressor having a different shape depending on the difference in output and the number of cylinders. It contains modifiable elements.

FIG. 1 is a front view of the two-stage air-cooled reciprocating compressor from the flywheel pulley side. When the flywheel pulley is drawn, the intercooler 3 and the aftercooler 10 behind it are obscured, and the flywheel Only the mounting position of the wheel pulley is shown by a dotted line. In FIG.
The atmosphere sucked through the suction filter 16 is further compressed by the low-pressure cylinder 1 and the rising temperature excluding the ambient temperature is introduced into the intercooler 3 through the introduction pipe 2 as the temperature rises to several hundreds of degrees. To be done. The air cooled by the intercooler 3 is introduced into the water separator 7 via the conducting pipe 6. The rising temperature cooled by the intercooler 3 is cooled to about 50 ° C. According to one experimental example, when the rising temperature of the first-stage discharge port is 152 ° C., the rising temperature cooled by the intercooler 3 and discharged is 49 ° C., and a cooling effect of about 100 ° C. is obtained. As the intercooler 3, a small cooler assembled in a box shape molded by aluminum die casting is used, and the aftercooler 10 of the same type is also used. The intercooler 3 is attached to the leg portion 4a of the crankcase 4 with two studs and nuts, which will be described in detail later.

The air from which water has been removed by the water separator 7 is supplied to the high-pressure cylinder, two-stage compression is performed, and the discharged air is introduced into the aftercooler 10 via the discharge pipe 9. According to one experimental example of the cooling effect of the aftercooler 10, the temperature rise immediately after the second-stage discharge is 126 ° C., and the temperature rise after being cooled and discharged by the aftercooler 10 is 56 ° C.
Thus, a cooling effect of about 70 ° C. is obtained. The description of the control system piping and the like in FIG. 1 will be omitted.

Further, as described above, the present embodiment has been described in the case of one high pressure cylinder and one low pressure cylinder.
Even in the case of a compressor body in which the low-pressure side is two-cylinder and the high-pressure side is one-cylinder, an intercooler and an aftercooler can be attached similarly to the above description, and the cylinder arrangement of the compressor and the shape of the crankcase, etc. It does not limit the invention.

In FIG. 2, the intercooler 3 and the aftercooler 10 are mounted between the flywheel pulley 14 and the crankcase 4 and below the crankshaft 11. When mounting both coolers, a step is formed on the bolt 17 in order to maintain an appropriate gap from the wall surface of the crankcase 4, that is, a gap through which cooling air can pass, and the bolt 17 is attached to the leg portion 4a of the crankcase 4. Is fixed by screwing. Then, the through holes of the mounting bosses 3a of both coolers are fitted and inserted into the bolts 17, and the mounting bosses 3a are brought into contact with the stepped portions of the bolts 17 so as to maintain a distance therebetween and are fixed by the nuts 5. Therefore, the heat is not transferred to the crankcase 4 due to the gap provided and the attachment by the bolt 17.

FIG. 3 is an enlarged partial sectional view of the mounting portions of both coolers. A known flywheel pulley 14 attached to the crankshaft 11 has ribs formed in a blade shape 14a and shares a cooling fan that generates cooling air by rotation. And, the blade portion of the cooling fan is
The cooling air is blown against both coolers. The intercooler 3 has a cross section taken along the same plane as the mounting boss 3a, and has a structure in which compressed air flows through a rectangular flow path 3b, and cooling air flows around the outer circumference of the flow path 3b to cool the compressed air. Two mounting bosses 3a are provided in the lower part of the intercooler 3, and through holes are bored. Two bolts 17 are screwed on the leg portion 4a of the crankcase 4.

As described above, the bolt 17 is a bolt with a step so that the intercooler 3 can be appropriately spaced from the wall surface of the crankcase 4, and the intercooler mounting portion 3a is attached to the stepped portion of the step. The end surface of the through hole of the abutment is brought into contact with the step and the appropriate distance is maintained. Then, the through hole of the mounting boss 3 a of the intercooler 3 is fitted into the bolt 17 and fixed by the nut 5. The number of the mounting bosses 3a is two in order to facilitate mounting at the time of mounting and to prevent rotation, and it goes without saying that the present invention is not limited to two. Further, the means for maintaining an appropriate space is another method, for example, a similar effect can be obtained even if a pipe-shaped collar is inserted in the space forming space. Is not limited to the above. The above description has been made for the intercooler 3, but the attachment of the aftercooler 10 is exactly the same, so the explanation is omitted.

[0019]

Since the present invention is constructed as described above, it has the following effects.

The intercooler, on the leg of the crankcase,
By directly mounting the and aftercoolers in parallel, the cost is low, with the two coolers, and the main body of a compact two-stage air-cooled reciprocating compressor with almost the same volume as the conventional one without aftercooler. With a cooler, it will be a low-cost body that has never been seen before.

Since the aftercooler is integrated with the compressor body and the heat exchange of both coolers is performed by the cooling fan of the flywheel pulley, the cooling fan conventionally provided only for the aftercooler is reduced, and Since it is not necessary to consider the installation space of the aftercooler, it greatly contributes to the cost reduction of the two-stage compressor.

By using the compressor body of the present invention in the package type compressor, piping in the package is simplified, the number of assembly steps of the package type compressor is greatly reduced, and the cost is reduced. Maintenance of the package type compressor becomes easy.

By installing both coolers in parallel with the legs of the crankcase and effectively utilizing the cooling air from the flywheel pulley in the lower half, which is comparatively less efficient in utilization, A sufficient cooling effect of both coolers can be obtained without reducing the cooling effect.

Since both coolers are attached in parallel to the crankcase legs and are attached with an appropriate interval from the wall surface of the crankcase, the exhaust hot air due to heat exchange between both coolers escapes from the interval. Because it is possible, it does not stay on the wall of the crankcase. Therefore, the temperature of the crankcase is not increased by directly flowing into the crankcase, and no trouble occurs in the compressor body. Furthermore, since both coolers are attached to the crankcase at appropriate intervals with bolts, heat transfer from both coolers to the crankcase leg does not occur due to heat dissipation by the bolts. Therefore, the temperature of the crankcase is not raised, and there is no risk of increasing the oil consumption and shortening the life of the bearing due to the rise in the oil temperature in the crankcase.

[Brief description of drawings]

FIG. 1 is a front view of a two-stage air-cooled reciprocating air compressor in which an intercooler and an aftercooler of the present invention are attached to a crankcase leg portion.

FIG. 2 is a side view of FIG.

FIG. 3 is a detailed enlarged cross-sectional view of the mounting portions of the intercooler and the aftercooler of the present invention.

[Explanation of symbols]

 1 Low Pressure Cylinder 3 Intercooler 3a Mounting Boss 4 Crankcase 4a Crankcase Leg 5,12 Nut 7 Water Separator 8 High Pressure Cylinder 10 Aftercooler 11 Crankshaft 13 Discharge Port 14 Flywheel Pulley 17 Bolt

Claims (2)

[Claims] 1. A low-pressure cylinder of a two-stage air-cooled reciprocating compressor,
An intercooler for intercooling the compressed air is attached in the middle of the pipeline that connects the high-pressure cylinders, and a water separator that removes the drain water condensed and separated by the intercooler is used.
In a multi-cylinder two-stage air-cooled reciprocating compressor in which an after-cooler is attached in the middle of a pipeline for introducing high-pressure air compressed by the high-pressure cylinder into the air tank by supplying air from the low-pressure cylinder to the high-pressure cylinder, the intercooler is used. And, the aftercooler is arranged in parallel between the crankcase and the flywheel of the two-stage air-cooled reciprocating compressor,
Two-stage air-cooling reciprocating compression in which both the coolers are directly attached to the crankcase, and cooling air from a flywheel pulley having a function of a cooling fan facing the both coolers is caused to flow through the both coolers for heat exchange. Machine cooling structure. 2. When the intercooler and the aftercooler are directly mounted in parallel to the crankcase of the two-stage air-cooled reciprocating compressor, the both coolers are directly mounted on the legs of the crankcase and both coolers are mounted. The cooling structure for a two-stage air-cooled reciprocating compressor according to claim 1, wherein the cooling means is attached to the wall surface of the crankcase with a means for maintaining an appropriate distance.