JP2528159Y2 - Reciprocating compressor - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reciprocating compressor suitable for use, for example, for generating compressed air.
The present invention relates to a reciprocating compressor capable of improving cooling efficiency.

[0002]

2. Description of the Related Art FIGS. 3 and 4 show an example of a conventional reciprocating compressor, which is a refueling reciprocating air compressor.

[0003] In the drawings, reference numeral 1 denotes a crankcase constituting a base of a compressor. The crankcase 1 is formed in a box shape having an opening 1A at an upper end side by a metal material such as cast iron. An insertion hole 1B through which a projecting shaft portion 2A of the crankshaft 2 described later is inserted is formed in one side surface of the crankcase 1, and a breathing plug 15 described later is inserted into the upper end side of the other side surface. A respiratory chamber 1C is formed.
The breathing chamber 1C is communicated with the inside of the crankcase 1 through a small-diameter communication hole 1D. Further, lubricating oil R for lubricating bearings 3 and 4 described later is injected into the crankcase 1.

[0004] Reference numeral 2 denotes a crankshaft rotatably disposed in the crankcase 1 via bearings 3 and 4. One end of the crankshaft 2 has an insertion hole 1 B of the crankcase 1.
Protruding shaft portion 2A protruding out of the crankcase 1 through the
A pulley 14, which will be described later, is attached to the protruding shaft portion 2A.

[0005] Reference numeral 5 denotes a compressor main body mounted on the crankcase 1, and 6 is provided in contact with the upper surface side of the opening 1 A of the crankcase 1. A cylinder constituting the compressor main body 5 is shown, and a plurality of cooling fins 6A, 6A,... Protruding radially outward are integrally formed on the outer peripheral side of the cylinder 6.

Reference numeral 7 denotes a cylinder head mounted on the cylinder 6, into which air sucked from a suction silencer 9 via a suction port 7A flows into the cylinder 6, as shown in FIG. And a discharge valve (not shown) that allows the compressed air compressed in the cylinder 6 to be discharged to the discharge port 7B side. The cylinder head 7 is provided with a substantially L-shaped rectifying plate 7C that is suspended from the upper side toward the outer peripheral side of the cylinder 6 so as to follow the flow of cooling air from a cooling fan 14A of a pulley 14 described later. The rectifying plate 7C is provided for effectively blowing the cooling air from the cooling fan 14A of the pulley 14 toward each cooling fin 6A of the cylinder 6. Further, the cylinder head 7 is located above the suction valve, and when the reciprocating compressor is driven, the suction valve is opened so that the compressor is operated without load. An unload mechanism 8 is provided for maintaining the state (unload state).

Reference numeral 9 denotes a suction silencer attached to the suction port 7A of the cylinder head 7. The suction silencer 9 reduces noise generated during suction and purifies air sucked into the cylinder 6. Things.

Reference numeral 10 denotes a closed-end cylindrical piston slidably inserted into the cylinder 6, and the piston 10 is provided with a piston pin 10A to which a small end 11A of a connecting rod 11 described later is connected. Have been.

Reference numeral 11 denotes a connecting rod provided between the crankshaft 2 and the piston 10. The connecting rod 11 has a small end rotatably connected at its upper end to a piston pin 10A via a bearing 12. Part 11A, the lower end of which is the crankshaft 2
Is a large end portion 11B rotatably connected to a middle portion of the same through a bearing 13. The large end 11B is integrally formed with an oil scraper 11C extending downward from the lower end thereof. The connecting rod 11 is connected to the crankshaft 2.
Is driven to rotate, this rotation is transmitted to the piston 10,
While reciprocating the piston 10 in the cylinder 6,
The lubricating oil R in the crankcase 1 is scraped up by an oil scraper 11C and supplied to the bearings 3, 4 and the like.

Reference numeral 14 denotes a large-diameter pulley fixed to the tip of the protruding shaft portion 2A of the crankshaft 2. The pulley 14 is connected to a motor or the like serving as an external drive source by a belt (both not shown).
, The crankshaft 2 is rotationally driven. The pulley 14 is integrally formed with a cooling fan 14A located on the crankcase 1 side. The cooling fan 14A rotates when the pulley 14 rotates (counterclockwise in the drawing). 5 is supplied with cooling air.

Reference numeral 15 denotes a respirator inserted at the upper end of the respiratory chamber 1C of the crankcase 1. The respirator 15 is configured to reciprocate when the pressure in the crankcase 1 becomes high or negative when the piston 10 reciprocates. The air in the case 1 is discharged into the suction silencer 9 through an oil return pipe 16 described later, or the air in the suction silencer 9 is sucked into the crankcase 1 so that the pressure in the crankcase 1
This is to prevent it from acting on zero.

Reference numeral 16 denotes an oil return pipe provided between the suction silencer 9 and the respirator 15. The oil return pipe 16 has an upper end connected to a lower end of the suction silencer 9.
The lower end is connected to the respirator 15. As a result, the oil return pipe 16 removes the air in the crankcase 1
5 and the suction silencer 9, and a part of the lubricating oil R contained in the air is removed by the suction silencer 9.
When the oil accumulates in the crankcase 1
It comes back inside.

The reciprocating air compressor according to the prior art has the above-described configuration, and its operation will be described below.

First, when the crankshaft 2 is driven to rotate integrally with the pulley 14 by an external drive source such as a motor, the rotation is performed by moving the piston 10 from the crankshaft 2 through the connecting rod 11 in the cylinder 6. Reciprocate. This allows
Air is sucked into the cylinder 6 from the suction silencer 9 via the suction port 7A and the suction valve, and this air is discharged from the discharge valve via the discharge port while being compressed by the piston 10.

In such a compressor, the suction valve is forcibly opened by the unloading mechanism 8 when the compressor is started, so that the inside of the cylinder 6 and the suction port 7A of the cylinder head 7 are communicated. Thus, in the no-load operation state (unload state), after the motor is raised to the rated speed, the forced opening of the suction valve is released to return to the normal compression operation state (load state), and the motor as a drive source And so on. Further, even when the inside of an air tank (not shown) reaches a predetermined pressure due to the compressed air discharged from the compressor, the suction valve is forcibly opened by the unloading mechanism 8 to enter a no-load operation state. It has become.

When the piston 10 moves down in the cylinder 6 and the pressure in the crankcase 1 increases during the operation of the compressor described above, the air in the crankcase 1 is discharged by the breathing plug 15 and the oil. The pressure in the crankcase 1 is reduced by being discharged to the suction silencer 9 via the return pipe 16 and the like. When the pressure in the crankcase 1 decreases (negative pressure) due to the rise of the piston 10, the air in the suction silencer 9 is removed from the crankcase 1 through the oil return pipe 16, the breathing plug 15, and the like. To increase the pressure in the crankcase 1. As a result, when the piston 10 reciprocates in the cylinder 6, the operating resistance due to the pressure in the crankcase 1 is prevented from acting on the piston 10.

On the other hand, when the compressor is operating, the pulley 14 rotates to generate cooling air from the cooling fan 14A, and this cooling air is supplied to each cooling fin 6A of the cylinder 6 to cool the compressor body 5. doing. Further, in the crankcase 1, the lubricating oil R in the crankcase 1 is scraped up by the oil scraping portion 11C of the connecting rod 11, and the bearing 3,
Each part is cooled by the lubricating oil R while lubricating 4 and the like.

[0018]

By the way, in the above-mentioned prior art, the pulley 14 is rotated to generate cooling air by the cooling fan 14A, and the cooling air is blown to the compressor body 5 so as to be cooled. The inside of the crankcase 1 is cooled by cooling the compressor from the outside and scraping up the lubricating oil R in the crankcase 1 by the oil scraping portion 11C of the connecting rod 11.

However, since the lubricating oil R is sealed in the crankcase 1, the temperature of the lubricating oil R rises due to an increase in the outside air temperature, continuous operation of the compressor, etc., so that the inside of the crankcase 1 is effectively cooled. Bearings,
For example, there is a problem that the reliability and the life are greatly reduced due to deterioration, damage and the like of No. 4 and the like.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and has a reciprocating compressor in which the air and lubricating oil in a crankcase are cooled so that the inside of the crankcase can be effectively cooled. The purpose is to provide.

[0021]

In order to solve the above-mentioned problem, a feature of the structure adopted in the present invention is that a cooling tank is provided at a position in the oil return pipe at a position to be cooled by cooling air from a pulley. That is.

[0022]

According to the above construction, when the piston descends and the pressure in the crankcase becomes high, the air and the lubricating oil in the crankcase flow into the cooling tank via the breathing plug and the oil return pipe, and are discharged from the pulley. Cooled by cooling air. When the piston rises and the pressure in the crankcase becomes negative, the air in the cooling tank is returned to the crankcase, and cools the lubricating oil in the crankcase.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 and 2 using a reciprocating air compressor as an example. In the embodiment, the same components as those in the prior art shown in FIGS. 3 and 4 are denoted by the same reference numerals, and description thereof will be omitted.

FIG. 1 shows a first embodiment of the present invention.

In the drawing, reference numeral 21 denotes an oil return pipe according to the present embodiment. The oil return pipe 21 has an upper end connected to a lower end of the suction silencer 9 in substantially the same manner as the oil return pipe 16 described in the prior art. Although the lower end is connected to the respirator 15, a cooling tank 22 described later is provided in an intermediate portion of the oil return pipe 21.

Reference numeral 22 denotes a rectangular cooling tank disposed in the middle of the oil return pipe 21 at a position to be cooled by cooling air from the cooling fan 14A of the pulley 14, and the cooling tank 22 is When the air discharged from the inside of the case 1 flows in through the breathing plug 15 and the oil return pipe 21, the heat of the air is radiated to the cooling air by the cooling fan 14A to cool.

The reciprocating air compressor according to the present embodiment has the above-described structure, and its basic operation is not particularly different from that of the prior art.

However, in this embodiment, a cooling tank 22 is provided in the middle of the oil return pipe 21 and the cooling tank 22 is connected to the pulley 1.
4, the cooling air is cooled by the cooling air from the cooling fan 14A, so that the high temperature air in the crankcase 1 flows through the respirator 15 or the like during the compression operation of the compressor.
When the air flows into the cooling fan 14, a part of the air is sucked into the suction silencer 9 side, but the remaining air is
The lubricating oil R in the crankcase 1 can be cooled by cooling with the cooling air of A and returning the crankcase 1 to the inside.

Also, when the compressor is operated with no load, the suction valve is forcibly opened by the unloading mechanism 8 provided on the cylinder head 7, so that the suction silencer 9 and the inside of the cylinder 6 are in communication. The air in the cooling tank 22 reciprocates between the inside of the crankcase 1 and the cooling tank 22 without being sucked into the suction silencer 9 side. Thereby, the lubricating oil R in the crankcase 1 can be effectively cooled by the air cooled in the cooling tank 22.

Thus, according to the present embodiment, the cooling air cooled in the cooling tank 22 flows into the crankcase 1 and the lubricating oil R in the crankcase 1 can be effectively cooled. In addition, it is possible to reliably prevent the bearings 3, 4 and the like from being deteriorated or damaged due to a rise in the temperature of the lubricating oil R, thereby greatly improving the reliability and life.

Next, FIG. 2 shows a second embodiment of the present invention, which is characterized in that a plurality of radiating fins are provided on the outer peripheral side of the cooling tank.

In the figure, reference numeral 31 denotes a rectangular cooling tank according to the present embodiment. The cooling tank 31 is provided in the middle of the oil return pipe 21 similarly to the cooling tank 22 described in the first embodiment. Although provided at a position where the pulley 14 is cooled by the cooling air from the cooling fan 14A, a plurality of cooling fins 31A, 31A projecting radially outward are provided on the outer peripheral side of the cooling tank 31. , ... are provided integrally.

Thus, in the present embodiment configured as described above, substantially the same operation and effect as those of the first embodiment can be obtained. In particular, in the present embodiment, a plurality of Are provided, the heat of the air flowing into the cooling tank 31 can be effectively radiated into the cooling air. As a result, by reliably cooling the lubricating oil R in the crankcase 1 with this air and supplying it to the bearings 3, 4, etc., it is possible to reliably prevent the bearings 3, 4 etc. from being deteriorated or damaged. Properties and life can be further improved.

In each of the above embodiments, the case where the rectangular cooling tanks 22 and 31 are used has been described as an example. However, the present invention is not limited to this, and the present invention is not limited to this. It may be formed in a shape.

In each of the above embodiments, the respirator 15 is
The case where the crankcase 1 is inserted into the breathing chamber 1C formed on the other side surface (opposite side of the pulley 14) has been described as an example. Instead, for example, the breathing room 1C is connected to one side surface (the pulley 14 side). And a respirator 15 may be inserted into the breathing chamber 1C. In this case, the pulley 14 can be effectively cooled by the cooling air from the cooling fan 14A of the pulley 14 without lengthening the oil return pipe 21. Cooling tanks 22 and 31 can be provided.

[0036]

As described in detail above, according to the present invention, since the cooling tank is provided at a position in the middle of the oil return pipe and cooled by the cooling air from the pulley, the piston descends. When the pressure in the crankcase becomes high, the air in the crankcase flows into the cooling tank via the breathing plug and the oil return pipe, and is cooled by the cooling air from the pulley. When the piston rises and the pressure inside the crankcase becomes negative, the air in the cooling tank is returned into the crankcase. As a result, the lubricating oil in the crankcase can be effectively cooled by the air cooled in the cooling tank, and the cooling efficiency of the reciprocating compressor can be improved.

[Brief description of the drawings]

FIG. 1 is an external view showing a reciprocating air compressor according to a first embodiment of the present invention.

FIG. 2 is an external view showing a reciprocating air compressor according to a second embodiment of the present invention.

FIG. 3 is a longitudinal sectional view showing a conventional reciprocating air compressor.

FIG. 4 is an external view of a reciprocating air compressor showing a piping state of an oil return pipe.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Crankcase 2 Crankshaft 5 Compressor main body 9 Suction silencer 10 Piston 14 Pulley 15 Respirator 21 Oil return pipe 22, 31 Cooling tank

Claims (1)

(57) [Scope of request for utility model registration] 1. A crankcase which rotatably accommodates a crankshaft, and compresses air sucked through a suction silencer while a piston mounted on the crankcase and connected to the crankshaft reciprocates. The compressor body,
A pulley that is provided outside the crankcase and rotationally drives the crankshaft and supplies cooling air to the compressor body; and a pulley that is provided in the crankcase and that is provided in the crankcase while the piston reciprocates. In a reciprocating compressor comprising a respirator for breathing and an oil return pipe connecting between the respirator and the suction silencer, in the middle of the oil return pipe, cooling air from the pulley is used. A reciprocating compressor comprising a cooling tank provided at a position to be cooled.