JPH08165995A - Rotary compressor - Google Patents

Abstract

PURPOSE: To provide a rotary compressor which is constituted to prevent the stop of rotation of the roller of a rotary compressor, prevent the occurrence of slide wear between the roller and a vane, and provide high reliability. CONSTITUTION: A rotary compressor comprises a cylinder 4; a vane 7 reciprocated in the cylinder 4; a roller 21 to effect rotation slide in the cylinder 4 and having an inner periphery formed in the shape of a taper in the direction of the height of the cylinder 4; and a crank 20 formed in the shape of a taper in the direction of the height of the cylinder 4 and slidably fitted in the roller 21.

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art A hermetic electric compressor used in a refrigerating machine has an electric compression element housed in a hermetic container.
There is a strong demand for highly reliable ones because maintenance and repair cannot be performed inside the closed container. Above all, the sliding parts of the rotary compressor rollers and vanes are in line contact,
It is in a severe sliding condition.

Therefore, there has been conventionally devised a method of preventing the lubrication failure of the sliding portion between the roller and the vane and improving the reliability. For example, there is a hermetic electric compressor as disclosed in JP-A-62-199990.

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

FIG. 3 is a sectional view showing a conventional rotary compressor, and FIG. 4 is a sectional view taken along the line AA of FIG.

In FIGS. 3 and 4, 1 is a closed casing, 1a is a refrigerant gas space, 2 is an electric element, and 3 is a shaft, which is composed of a main shaft 3a, an auxiliary shaft 3b, and an eccentric portion 3c.
Reference numeral 4 is a cylinder, 5 is a roller rotatably housed in the eccentric portion 3c of the shaft 3, 6 is a vane groove provided in the cylinder, and 7 is a vane that reciprocates in the vane groove 6. . Reference numeral 8 is a main bearing and 9 is a sub bearing, which are fixed to the end surface of the cylinder 4.

Reference numeral 10 is a spring provided between the rear surface of the vane 7 and the cylinder 4. Reference numerals 11a and 11b denote a suction chamber and a compression chamber, respectively, which are constituted by a roller 5, a vane 7, a main bearing 8 and a sub bearing 9 in the cylinder 4. Reference numeral 12 is an oil supply mechanism including a coil spring 12a fixed to the sub shaft 3b and a guide tube 12b fixed to the sub bearing 9.

Reference numeral 13 denotes a suction pipe, which is a suction chamber 11a at a suction portion 15 via a sub bearing 9 and a suction passage 14 of the cylinder 4.
Is in communication with 16 is a discharge part, 17 is a discharge valve, and 18 is a discharge pipe. Reference numeral 19 is a lubricating oil in the closed casing 1.

The operation of the rotary compressor configured as described above will be described below. The refrigerant gas is guided from the cooling system (not shown) to the suction pipe 13, the suction passage 14, and the suction portion 15 and reaches the suction chamber 11a in the cylinder 4. The refrigerant gas that has reached the suction chamber 11a is transferred to the crank 3 of the shaft 3
In the compression chamber 11b partitioned by the roller 5 and the vane 7 which are rotatably housed in c, the shaft 3 is gradually compressed by the rotation of the electric element 2.

At this time, the roller 5 makes a rotational movement (revolution) around the shaft 3 with respect to the fixed coordinate system of the main bearing 8, the auxiliary bearing 9, etc., and at the same time, performs a rotational movement (rotation) about the center of the eccentric portion 3c. I do. Then, due to this revolution and rotation, a relative speed is generated between the roller 5 and the vane 7,
Due to the relative speed, an oil film is generated between the roller 5 and the vane 7.

The compressed refrigerant gas is once discharged into the closed casing 1 through the discharge portion 16 and the discharge valve 17, and then discharged through the discharge pipe 18 into the cooling system.

The lubricating oil 19 accumulated in the lower portion of the closed casing 1 is the coil spring 12 fixed to the sub shaft 3b.
It reaches the sub shaft 3b through a and lubricates the sliding portions of the shaft 3 and the roller 5. Further, between the vane 7 and the vane groove 6 of the cylinder 4, when the vane 7 reciprocates, it is soaked in the lubricating oil 19 stored in the closed casing 1 so that a sliding portion between the vane 7 and the vane groove 6 is formed. Lubricated and sealed.

[0013]

However, in the above-mentioned conventional structure, the rotation of the roller 5 is such that the outer peripheral surface of the roller 5 and the cylinder 4 or the vane 7, the end surface of the roller 5 and the main bearing 8 or the sub bearing 9, and the inner peripheral surface of the roller 5. And the eccentric portion 3c are determined by the viscous force and frictional force of the lubricating oil. Further, regarding the rotary compressor in which the cylinder volume is selected according to the height of the cylinder 4, the height of the cylinder 4 becomes low when the cylinder volume is small.

Among the forces that determine the rotation of the roller 5, the viscous force of the lubricating oil acting between the inner peripheral surface of the roller 5 and the eccentric portion 3c acts to promote the rotation of the roller 5, and The force is almost proportional to the surface area of the sliding portion. Further, the viscous force and frictional force of the lubricating oil acting on the roller 5 and the cylinder 4, the vane 7, and the end face of the roller 5 and the sliding portion of the main bearing 8 and the auxiliary bearing 9 act to stop the rotation of the roller 5. .

Therefore, when the roller 5 has a small cylinder volume and the height of the roller 5 is low, the viscous force between the inner peripheral surface of the roller 5 and the eccentric portion 3c for promoting the rotation of the roller 5 is reduced, and the rotation of the roller 5 is reduced. The viscous force and the frictional force acting between the outer peripheral surface of the roller 5 and the cylinder 4 or the vane 7 and the end surface of the roller 5 and the main bearing 8 or the sub-bearing 9 are larger.

Therefore, particularly in a cylinder having a low height of the cylinder 4 and a small cylinder volume, the rotation of the roller 5 decreases, the relative speed of the sliding portion of the roller 5 and the vane 7 decreases, and it becomes difficult to generate an oil film. . Therefore, there is a drawback in that the sliding portion between the roller 5 and the vane 7 causes metal contact due to the oil film breakage, and the sliding portion is worn.

The present invention solves the conventional problems, and prevents the rotation of the roller 5 from decreasing even when the height of the cylinder 4 is low, and prevents the oil film between the roller 5 and the vane 7 from running out. The purpose is to prevent abrasion of the sliding part due to metal contact.

Further, in the above-mentioned conventional construction, the temperature of the sliding portion rises under high outside temperature conditions, the oil viscosity of the sliding portion becomes considerably low, and the lubrication acting between the inner circumference of the roller 5 and the eccentric portion 3c is achieved. The viscous force of the oil may decrease, and the rotation of the roller 5 may extremely decrease. Therefore, when the temperature of the sliding portion is high due to high outside air temperature, the relative speed between the roller 5 and the vane 7 is extremely reduced, making it difficult to generate an oil film between the roller 5 and the vane 7. There was a drawback that the parts would wear out.

Another object of the present invention is to prevent the rotation of the roller 5 from deteriorating and prevent the oil film from running out between the roller 5 and the vane 7 when the temperature of the sliding portion becomes high due to high outside air temperature. , To prevent abrasion of sliding parts.

[0020]

To achieve this object, a hermetic compressor of the present invention has a cylinder, a vane that reciprocates in the cylinder, and a rotary slide in the cylinder. A roller that is tapered in the depth direction,
It is composed of a crank which is tapered in the height direction of the cylinder and which is slidably fitted to the roller.

Further, the cylinder, the vane which reciprocates in the cylinder, the eccentric portion which rotates and slides in the cylinder, and the eccentric portion which are slidably fitted to each other and are provided with grooves formed on the inner peripheral surface. It has a roller and a telescopic mechanism which is arranged in the groove in the radial direction and expands at a high temperature and contracts at a low temperature.

[0022]

The hermetic compressor of the present invention includes a cylinder, a vane that reciprocates in the cylinder, and a rotary slide in the cylinder.
Since the roller whose inner circumference is tapered in the height direction of the cylinder and the crank that is slidably fitted in the height direction of the cylinder and is slidably fitted to the roller are provided, the cylinder volume is small and the cylinder height is small. Even if it is low, the sliding area between the inner circumference of the roller and the crank can be increased.

Therefore, it is possible to increase the viscous force between the inner peripheral surface of the roller and the crank, prevent the rotation of the roller from decreasing, and prevent the relative speed between the roller and the vane from decreasing. Therefore, the oil film between the roller and the vane can be prevented from running out, and the wear of the sliding portion can be prevented.

Further, the cylinder, the vanes that reciprocate in the cylinder, the eccentric portion that rotationally slides in the cylinder, and the groove that is slidably fitted to the eccentric portion and is provided in the inner peripheral surface are formed. Since it has a roller and a telescopic mechanism that is arranged radially in the groove and expands at high temperature and contracts at low temperature, the temperature of the sliding part becomes high due to high outside air temperature etc. Even if the viscosity of the lubricating oil decreases, the expansion / contraction mechanism provided inside the roller expands, and the frictional force between the eccentric portion and the roller increases.

Therefore, by promoting the rotation of the rollers, the oil film between the rollers and the vanes can be prevented from running out, and the abrasion of the sliding parts can be prevented.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the hermetic compressor according to 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 is a longitudinal sectional view of a main part of a rotary compressor according to a first embodiment of the present invention. In FIG. 1, reference numeral 20 denotes a crank which is rotationally slid in the cylinder 4 and has a taper shape in the height direction of the cylinder, and 21 has an inner circumference which is tapered in the height direction of the cylinder and slides with the crank 20. A roller that fits freely.

The operation of the hermetic compressor constructed as described above will be described below. The roller 21 revolves around the shaft 3 with the rotation of the electric element 2 about the main bearing 8 and the sub bearing 9, and also rotates about the center of the crank 20. The sliding area between the circumferential surface of the crank 20 and the inner circumferential surface of the roller 21 has a taper shape in the height direction of the cylinder 4, so that the sliding area is large.

Since the viscous force due to the lubricating oil between the crank 20 and the roller 21 is almost proportional to the sliding area thereof, even if the height of the cylinder 4 is low, the inner circumference between the roller 21 and the crank 20 is small. The viscous force of can be increased. Therefore, it is possible to prevent the rotation of the roller 21 from decreasing,
Since it is possible to prevent the relative speed between the roller 21 and the vane 7 from decreasing, it is possible to prevent the oil film from running out between the roller 21 and the vane 7, prevent the metal contact of the sliding part, and prevent the sliding part from wearing. You can

As described above, the rotary compressor of this embodiment is
A crank 20 that is slidably rotated in the cylinder 4 and has a taper shape in the height direction of the cylinder, and a roller 21 that has an inner circumference that is tapered in the height direction of the cylinder and is slidably fitted to the crank 20. Since it is configured, even if the height of the cylinder 4 is low, the viscous force between the inner circumference of the roller 21 and the crank 20 can be increased.

Therefore, the rotation of the roller 21 can be prevented from lowering, and the relative speed between the roller 21 and the vane 7 can be prevented from decreasing, so that the oil film between the roller 21 and the vane 7 can be prevented and the sliding portion can be prevented. Metal contact can be prevented, and abrasion of sliding parts can be prevented.

Although the crank 20 and the roller 21 are tapered in this embodiment, it is needless to say that the same effect can be obtained even if the crank 20 and the roller 21 have a wide sliding area. .

Next, the second embodiment of the rotary type compressor according to the present invention
Embodiments will be described with reference to the drawings. It should be noted that the same components as those of the related art are designated by the same reference numerals and detailed description thereof is omitted.

FIG. 2 is a longitudinal sectional view of a main part of a rotary compressor according to a second embodiment of the present invention. In FIG. 2, reference numeral 22 denotes a rotatable roller fitted in the eccentric portion 3c,
Is a groove provided on the inner peripheral surface of the roller 22, and 24 is an expansion and contraction mechanism which is arranged in the groove 23 in the radial direction and extends at a high temperature and contracts at a low temperature. A shape memory alloy or the like is used as the expansion / contraction mechanism 24.

The operation of the rotary compressor constructed as above will be described below. Even if the temperature of the rotary compressor rises due to high outside air temperature and the viscosity of the lubricating oil between the roller 22 and the eccentric portion 3c decreases, the expansion mechanism 24 extends and presses the roller 22 against the eccentric portion 3c. . Therefore, in the sliding portion of the expansion / contraction mechanism 24, the frictional force between the inner circumference of the roller 22 and the eccentric portion 3c increases via the expansion / contraction mechanism 24. Further, on the side opposite to the expansion / contraction mechanism 24 in the circumferential direction, the roller 22
The inner periphery of the load increases between the eccentric portions 3c,
Friction force increases.

Therefore, the temperature of the sliding portion rises during the operation of the rotary compressor, the viscosity of the lubricating oil between the roller 22 and the eccentric portion 3c decreases, and the roller 22 acts to promote the rotation of the roller 22. Even if the viscous force and the frictional force between the eccentric portion 22 and the eccentric portion 3c decrease, the roller 22 can be rotated by the frictional force of the expansion / contraction mechanism 24. Therefore, it is possible to prevent the relative speed between the vane 7 and the roller 22 from decreasing, and the roller 2
Since the oil film of 2 and the vane 7 can be prevented from running out, abrasion of the sliding portion can be prevented.

Further, depending on the operating condition of the rotary compressor,
When the temperature of the sliding portion is not too high, the expansion / contraction mechanism 24 contracts without pressing the roller 22 against the eccentric portion 3c.
The eccentric portion 3c and the roller 22 slide like the conventional one.
Therefore, the roller 22 and the eccentric portion 3c
Rotation is promoted only by viscous force and frictional force, and the number of rotation does not increase extremely. Therefore, it is possible to prevent the sliding portion from being worn due to an increase in the sliding distance as the relative speed between the roller 22 and the vane 7 increases.

As described above, the rotary compressor of this embodiment is
A rotatable roller 22 fitted into the eccentric portion 3c, a groove 23 provided in the inner peripheral surface of the roller 22, a radial arrangement in the groove 23, and an expansion mechanism 24 that expands at high temperature and contracts at low temperature.
Therefore, the temperature of the sliding portion rises during the operation of the rotary compressor, the viscosity of the lubricating oil becomes low, and the roller 22
Roller 22 and eccentric portion 3 that act to promote rotation of the roller
Even if the viscous force and frictional force between c are reduced, the roller 22 can be rotated by the frictional force of the expansion / contraction mechanism 24.

Therefore, it is possible to prevent the oil film of the roller 22 and the vane 7 from running out, so that it is possible to prevent wear of the sliding portion. Further, depending on the operating condition of the rotary compressor, when the temperature of the sliding portion is not so high, the sliding is the same as the conventional one. Therefore, the rotation of the roller 22 is promoted only by the viscous force and frictional force of the roller 22 and the eccentric portion 3c, and the number of rotations does not increase extremely. Therefore, the roller 22 and the vane 7
It is possible to prevent the wear of the sliding portion due to the increase of the sliding distance with the increase of the relative speed of.

A shape memory alloy or the like can be considered as the expansion mechanism 24, but it goes without saying that the same effect can be obtained by changing the frictional force between the roller 22 and the eccentric portion 3c by another method.

[0041]

As described above, according to the present invention, a crank having a tapered shape in the height direction of the cylinder, which is slidably rotated in the cylinder, and an inner circumference having a tapered shape in the height direction of the cylinder, Since the roller is slidably fitted to the cylinder, the viscous force between the inner circumference of the roller and the crank can be increased even if the height of the cylinder is low. Therefore, even if the cylinder height is low, the rotation of the roller can be secured and the relative speed between the roller and the vane can be prevented from decreasing, so that the oil film between the roller and the vane can be prevented, and the metal of the sliding part can be prevented. Contact can be prevented, and abrasion of sliding parts can be prevented.

Further, a rotatable roller fitted into the eccentric portion, a groove provided on the inner peripheral surface of the roller, and a radial arrangement within the groove are provided to expand / contract at high temperature and contract at low temperature. As it is configured, the temperature of the sliding part rises during operation of the rotary compressor, the viscosity of the lubricating oil decreases, and the viscous force and friction between the roller and the eccentric part that act to promote rotation of the roller Even if the force decreases, the roller can be rotated by the frictional force of the expansion and contraction mechanism.

Therefore, the relative speed between the roller and the vane can be prevented from lowering, and the oil film of the roller and the vane can be prevented from running out, so that the wear of the sliding portion can be prevented. Further, depending on the operating condition of the rotary compressor, when the temperature of the sliding portion is not so high, the sliding is the same as the conventional one. Therefore, the rotation of the roller is promoted only by viscous force and frictional force between the roller and the eccentric portion, and the number of rotation does not increase extremely. Therefore, it is possible to prevent the wear of the sliding portion due to the increase of the sliding distance with the increase of the relative speed of the roller and the vane.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a main part of a first embodiment of a rotary compressor according to the present invention.

FIG. 2 is a longitudinal sectional view of a main part of a second embodiment of the rotary compressor according to the present invention.

FIG. 3 is a vertical sectional view of a conventional hermetic compressor.

FIG. 4 is a sectional view taken along line AA of FIG.

[Explanation of symbols]

 3c Eccentric part 4 Cylinder 7 Vane 20 Crank 21 Roller 22 Roller 23 Groove 24 Expansion mechanism

Claims (2)

[Claims] 1. A cylinder, a vane that reciprocates in the cylinder, a roller that slides in the cylinder and has an inner circumference that is tapered in the height direction of the cylinder, and a height direction of the cylinder. A rotary compressor having a tapered shape and a crank slidably fitted to the roller. 2. A cylinder, a vane that reciprocates in the cylinder, an eccentric portion that rotationally slides in the cylinder, and an eccentric portion that are slidably fitted and are provided on an inner peripheral surface. A rotary compressor comprising a roller having a groove and a telescopic mechanism arranged in the groove in a radial direction and extending at a high temperature and contracting at a low temperature.