JPH08159030A - Enclosed compressor - Google Patents

Abstract

PURPOSE: To improve oil film forming capacity, and prevent abrasion on a sliding part by providing a rotatable cylinder bearing in which a cylinder shaft is inserted, and a movable cylinder which is formed integratedly with the cylinder bearing and which is moved around the cylinder shaft. CONSTITUTION: When a compressor is operated and a crank shaft 4 is rotated, an eccentric part 11 is also rotated in compliance therewith, and the piston part 24a of a connecting rod 24 with a piston is performed reciprocating motion against a movable cylinder 23 by the eccentric part 11 so as to compress refrigerant. At this time, the movable cylinder 23 is performed oscillating motion around a cylinder shaft 22 following with oscillating motion of the piston part 24a, and thereby the piston part 24a and the movable cylinder 23 are oscillated smoothly. Oscillating motion is supported in condition in which bearing pressure is reduced such as the cylinder shaft 22 and a cylinder bearing 20. It is thus possible to prevent lubricating failure in the sliding part and metal contact which is caused by oil film shortage, and also it is possible to suppress abrasion.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reciprocating hermetic compressor used for a refrigerating machine or the like.

[0002]

2. Description of the Related Art A hermetic compressor used in a refrigerating machine or the like has an electrically driven compression element housed in a hermetically sealed container, and maintenance and repair cannot be performed in the hermetically sealed container. It is rare. Above all, the eccentric part of the crankshaft of the reciprocating compressor and the large end hole of the connecting rod, and the sliding part of the piston pin and the small end hole of the connecting rod are subjected to a large surface pressure due to compression and are in a severe sliding state. Therefore, a method of improving reliability by preventing poor lubrication of the sliding portions between the crankshaft eccentric portion and the connecting rod large end hole and between the piston pin and the connecting rod small end hole has been conventionally devised. For example, JP-A-2-275072
There is a hermetic compressor as disclosed in Japanese Patent Publication No.

An example of the conventional hermetic compressor described above will be described below with reference to the drawings.

FIG. 4 is a sectional view showing a conventional hermetic compressor. In FIG. 4, reference numeral 1 is a cylinder in which a piston 2 reciprocates. Reference numeral 3 is a bearing that supports the crankshaft 4. The piston 2 has a hollow portion 5 and a through hole 6 in a direction orthogonal to the axial direction.

Reference numeral 7 is a connecting rod having a small end hole 8 at one end and a large end hole 9 at the other end. Reference numeral 10 is an oil supply hole that passes through the connecting rod 7 and connects the small end hole 8 and the large end hole 9 to each other.

Reference numeral 11 is an eccentric portion formed on the crankshaft 4. Reference numeral 12 is a shaft oil supply hole formed in the crankshaft 4, and 13 is an eccentric part oil supply hole that communicates with the shaft oil supply hole 12 and opens into an oil sump 14 provided on the surface of the eccentric part 11. .

Reference numeral 15 is an oil supply pipe fixed to the crank eccentric portion 11, and communicates with the shaft oil supply hole 12.
Oil 16 stored in the bottom of the closed container (not shown)
Is soaked in. The small end hole 8 of the connecting rod 7 is inserted into the hollow portion 5 of the piston 2, and the through hole 6 and the small end hole 8 are formed.
The piston 2 is connected to the crankshaft 4 by inserting the piston pin 17 into the and the eccentric portion 11 into the large end hole 9. Reference numeral 18 is a circumferential groove provided on the surface of the piston pin 17 in the circumferential direction, and 19 is a locking pin for fixing the piston pin 17 to the piston 2.

The operation of the hermetic compressor constructed as described above will be described below. As the crankshaft rotates, oil pressure is generated in the oil 16 in the oil supply pipe 15, and the oil 16 rises in the oil supply pipe 15 and the shaft oil supply hole 12. Part of the raised oil 16 is the eccentric part oil supply hole 13
Through the oil reservoir 14 and then lubricates the sliding portion between the large end hole 9 and the eccentric portion 11. In addition, the oil sump 14
A part of the oil flows through the oil supply hole 10 to the small end hole 8, lubricates the sliding portion between the piston pin 17 and the small end hole 8, and flows through the circumferential groove 18 into the hollow portion 5 of the piston 2. To do.

Further, the rotation of the oil supply pipe 15 causes
The oil 16 is splashed on the large end hole 9, the small end hole 8, the piston 2, etc., and the sliding portions thereof are lubricated and cooled.

With this structure, the small end hole 8 and the large end hole 9 can be cooled and lubricated by the oil 16, so that abrasion and seizure due to metal contact can be made difficult.

[0011]

However, in the above-mentioned conventional structure, the sliding portion between the small end hole and the piston pin makes a swinging motion, and a large compressive load is applied to the surface, so that the surface pressure is high. It is difficult to generate a sufficient oil film pressure, and there is a drawback that the small end hole portion is worn due to metal contact due to oil film breakage.

The present invention solves the above-mentioned conventional problems by eliminating sliding between the connecting rod small end hole and the piston pin,
Instead, by sliding with a bearing whose bearing pressure is lower than that of the small end hole, the oil film formation capability is increased,
The purpose of the present invention is to provide a highly reliable hermetic compressor that prevents sliding parts from being worn.

Further, in the above-mentioned conventional structure, as the oil level lowers, the amount of oil splashing on the large end hole by the oil supply pipe decreases and the cooling effect decreases. There is a drawback that the large end hole is worn due to the decrease in oil film forming ability due to the decrease in viscosity.

Another object of the present invention is when the oil level is lowered by a cooling blade fixed to a movable cylinder or a cylinder bearing and provided at a position where it is immersed in oil, and the amount of oil splashed by the oil supply pipe is reduced. Also, by splashing oil on the large end hole with cooling blades,
The purpose of the present invention is to provide a highly reliable hermetic compressor that cools the sliding portion to prevent wear.

[0015]

In order to achieve this object, a hermetic compressor of the present invention has a crankshaft having an eccentric portion, an upper bearing for supporting the crankshaft, and a fixed to the upper bearing. And a movable cylinder that is rotatable with the cylinder shaft inserted therein, the cylinder bearing being rotatable, the cylinder bearing being integral with the cylinder bearing, and having a large end hole at one end, It has a piston part at the other end, the eccentric part is inserted into the large end hole, and the piston-equipped connecting rod has the piston part inserted into the movable cylinder.

Further, the structure is further provided with an oil stored in the lower portion of the closed container and a cooling blade fixed to a movable cylinder or a cylinder bearing, at least a part of which is immersed in the oil.

[0017]

The hermetic compressor according to the present invention can eliminate the sliding which has been conventionally performed by the connecting rod small end hole and the piston pin, and instead, the cylinder bearing and the cylinder shaft slide. become. Therefore, the bearing sliding area can be made larger than in the past, sliding lubrication can be performed in a state where the surface pressure is lower, and the oil film is less likely to run out, preventing lubrication failure in the sliding part. It is possible to make the sliding portion less likely to wear.

Further, at least a part is soaked in the oil,
Since the cooling vanes fixed to the movable cylinder or cylinder bearing are provided, the oil level will be low, and even if the amount of oil splashed by the oil supply pipe is small, the oil will not splash to the large end hole of the connecting rod. Therefore, it is possible to cool the large end hole portion, prevent poor lubrication in the sliding portion, and make the sliding portion of the large end hole less likely to wear.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the hermetic compressor of the present invention will be described below with reference to the drawings. It should be noted that the same components as those of the related art will be denoted by the same reference numerals and detailed description thereof will be omitted.

FIG. 1 shows a first embodiment of the hermetic compressor of the present invention. FIG. 2 is a sectional view taken along line AA in FIG.

In FIGS. 1 and 2, 20 is a cylinder bearing, 21 is an upper bearing for supporting the crankshaft 4, and 22 is a cylinder shaft fixed to the upper bearing 21. A cylinder shaft 22 is inserted into the cylinder bearing 20 so as to be rotatable. 23
Is a movable cylinder which is integrated with the cylinder bearing 20 and is movable around a cylinder shaft 22.
Has a large end hole 9 at one end and a piston portion 24a at the other end,
The eccentric part 11 is inserted into the large end hole 9, and the movable cylinder 23
It is a connecting rod with a piston in which the piston portion 24a is inserted.

The operation of the hermetic compressor constructed as described above will be described below. When the compressor operates and the crankshaft 4 rotates, the eccentric portion 11 also rotates accordingly, and the eccentric portion 11 causes the piston portion 24a of the connecting rod with piston 24 to reciprocate with respect to the movable cylinder 23 to compress the refrigerant. To do. At this time, unlike the conventional structure having the connecting rod small end hole portion, the piston portion 24a does not make a simple reciprocating motion, and the connecting rod with piston 24 and the piston portion 24a are integrated so that the swinging motion is prevented. Become. At this time, the movable cylinder 23 swings around the cylinder shaft 22 as a fulcrum in accordance with the swing movement of the piston portion 24a, so that the piston portion 20a and the movable cylinder 23 slide smoothly. Therefore, unlike the conventional structure, the contact pressure of the connecting rod small end hole 8 or the sliding portion with high lubrication is eliminated, and instead of the small end hole 8 and the piston pin 17 like the cylinder shaft 22 and the cylinder bearing 20. The swinging motion can be supported with the surface pressure kept low. Therefore, poor lubrication of sliding parts,
Metal contact due to oil film breakage can be prevented, and abrasion can be made less likely.

The movable cylinder 23 has a piston portion 2
4a, the moving direction of the force applied to the piston portion 24a and the movable cylinder 23 of the piston portion 24a.
Since the moving direction with respect to is on the same straight line, the lateral force of the movable cylinder 24 can be reduced. Therefore,
The contact load between the piston portion 24a and the movable cylinder 23 can be reduced, and the sliding portion between the piston portion 24a and the movable cylinder 23 can be less likely to wear.

As described above, the hermetic compressor of this embodiment is
A crankshaft 4 having an eccentric portion 11, an upper bearing 21 that supports the crankshaft 4, a cylinder shaft 22 fixed to the upper bearing 21, and a cylinder bearing 20 into which the cylinder shaft 22 is inserted and which is rotatable, A movable cylinder 23 which is integrated with the cylinder bearing 20 and is movable around a cylinder shaft 22, a large end hole 9 at one end, and a piston portion 24a at the other end, and the eccentric portion 11 is provided in the large end hole 9. Since it is composed of the connecting rod with piston 24 in which the piston portion 24a is inserted into the movable cylinder 23, the sliding movement of the small end hole 8 is replaced with the swinging movement performed at the sliding portion of the small end hole 8. Since sliding can be performed by the cylinder bearing 20 having a surface pressure lower than that of the moving part, the sliding part is caused by poor lubrication of the sliding part or metal contact due to oil film breakage. It can be difficult to wear.

Next, a second embodiment of the hermetic compressor of the present invention will be described with reference to the drawings. The same components as those in the conventional example and the first embodiment are designated by the same reference numerals and detailed description thereof will be omitted.

FIG. 3 shows a second embodiment of the hermetic compressor of the present invention. In FIG. 3, 25 is oil 16
Is a cooling blade fixed to the movable cylinder 23 or the cylinder bearing 20.

The operation of the hermetic compressor constructed as described above will be described below. Oil 16 remains in the system while the compressor is operating
The cooling blade 25 performs a rotational movement even when the oil 16 cannot be splashed into the large end hole 9 in the oil supply pipe 15 due to a decrease in the amount of oil or a lowering of the oil surface due to forming. Since it is fixed to the movable cylinder 23 or the cylinder bearing 20, the oil 16 is splashed on the large end hole 9 by the cooling blade 25. Therefore, even when the oil level is low, the sliding portion of the large end hole 9 can be cooled, the oil film forming ability can be enhanced, and the sliding portion of the large end hole 9 can be less likely to wear.

As described above, the hermetic compressor of this embodiment is
In addition to the effects of the first embodiment, at least a part of the oil 16 is immersed in the oil 16 and the cooling blade 25 fixed to the movable cylinder 23 or the cylinder bearing 20 is provided. Even when the surface is low, the oil 16 can be splashed on the sliding portion of the large end hole 9, and the sliding portion of the large end hole 9 can be cooled. Therefore, it is possible to prevent the deterioration of the oil film forming ability and the poor lubrication due to the temperature rise of the sliding portion of the large end hole 9, and to prevent the sliding portion from being worn easily.

[0029]

As described above, according to the present invention, a crankshaft having an eccentric portion, an upper bearing that supports the crankshaft, a cylinder shaft fixed to the upper bearing, and the cylinder shaft are inserted. A rotatable cylinder bearing, a movable cylinder which is integrated with the cylinder bearing and can move around the cylinder shaft, a large end hole at one end, and a piston portion at the other end, and the large end Since the eccentric portion is inserted in the hole and the piston-containing connecting rod in which the piston portion is inserted in the movable cylinder, the small end instead of the swinging movement performed in the sliding portion of the small end hole is used. Sliding can be performed with a cylinder bearing whose surface pressure is lower than that of the sliding part of the hole, and abrasion of the sliding part caused by metal contact due to oil film breakage is less likely to occur. Can.

Further, according to the present invention, the oil stored in the lower part of the closed container and the cooling blade fixed to the movable cylinder or the cylinder bearing at least partly immersed in the oil are provided. Even when the oil level in the closed container is low, the cooling blades can splash the oil on the sliding part of the large end hole, and the sliding part of the large end hole can be cooled. It is possible to prevent the deterioration of the oil film forming ability and the poor lubrication due to the temperature rise of the parts, and to make the sliding parts less likely to wear.

[Brief description of drawings]

FIG. 1 is a sectional view of a piston device for a hermetic compressor showing a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view of a piston device of a hermetic compressor showing a second embodiment of the present invention.

FIG. 4 is a sectional view of a piston device of a conventional hermetic compressor.

[Explanation of symbols]

 4 Crankshaft 9 Large End Hole 11 Eccentric Part 16 Oil 20 Cylinder Bearing 21 Upper Bearing 22 Cylinder Shaft 23 Movable Cylinder 24 Piston Connecting Rod 24a Piston Part 25 Cooling Blade

Claims (2)

[Claims] 1. A crankshaft having an eccentric part, an upper bearing for supporting the crankshaft, a cylinder shaft fixed to the upper bearing, and a rotatable cylinder bearing into which the cylinder shaft is inserted. A movable cylinder, which is integrated with the cylinder bearing and is movable around the cylinder shaft, has a large end hole at one end and a piston portion at the other end, and the eccentric portion is inserted into the large end hole, A hermetic compressor comprising a connecting rod with a piston in which the piston portion is inserted into the movable cylinder. 2. Oil stored in the lower part of the closed container,
The hermetic compressor according to claim 1, further comprising a cooling blade fixed to a movable cylinder or a cylinder bearing, the cooling blade being at least partially immersed in the oil.