JPH09151891A - Hermetic type rotary compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the generation of trouble and the lowering of compression efficiency caused by the wear and breaking of a compression spring for driving a piston of displacement control mechanism by holding the intermediate part of the compression spring of the displacement control mechanism to a third hole. SOLUTION: Compression chambers 8A, 8B are provided at the peripheral direction side walls of first and second cylinders 6A, 6B. First holes 11A, 11B communicate with these compression chambers 8A, 8B, and second holes 12A, 12B communicate with the first holes 11A, 11B. A third hole 13 piercing a partition plate 5 communicate with the second holes 12A, 12B. A compression spring 15 is inserted through the third hole 13, and an intermediate part 15 of the compression spring 15 is held to the third hole 13 of the partition plate 5. This constitution can prevent the generation of trouble and the lowering of compression efficiency caused by the wear and breaking of the compression spring 15.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-cylinder hermetic rotary compressor mounted in, for example, an air conditioner or a refrigerator, and more particularly, by improving a capacity control mechanism provided in a rotary compression element. It is intended to prevent the occurrence of troubles due to wear and breakage of the compression spring driving the piston of the capacity control mechanism and the reduction of compression efficiency.

[0002]

2. Description of the Related Art Conventionally, in a two-cylinder hermetic rotary compressor of this type, as shown in FIG. 6, a hermetically-sealed container 1 is driven by an electric element 2 and a crankshaft 3 of the electric element 2. While the rotary compression element 4 is housed therein, the inner bottom surface of the closed container 1 serves as an oil sump portion 1A of the lubricating oil O supplied to the drive parts of the electric element 2 and the rotary compression element 4, As the rotary compression element 4, piston rollers 7A and 7B provided in first and second cylinders 6A and 6B vertically partitioned by a partition plate 5 are alternately eccentric with the crankshaft 3 of the electric element 2. Rotate each of these cylinders 6
The compression chambers 8A and 8B formed by A and 6B and the piston rollers 7A and 7B are attached to one outer side portion 1a of the closed container 1.
The refrigerant gas G is alternately supplied through the suction pipe 9A facing from the side, and the compressed refrigerant gas G is connected to a refrigerant unit circuit (not shown) provided at the top of the closed container 1 while repeating the suction / compression process. It is made to discharge to the outside from the discharge pipe 9B, and the other outer side portion 1 of the closed container 1
There is a structure in which a capacity control mechanism 10 for controlling the capacity of the rotary compression element 4 is provided on the b side.

As shown in FIG. 7, the capacity control mechanism 10 having such a conventional structure has the compression chambers 7A, 7B respectively provided on the outer circumferential side walls of the first and second cylinders 6A, 6B. The first holes 11A, 11 communicating with the
B and the first holes 11A and 11B so as to communicate with each other in the rotation axis direction of the crankshaft 3 via the partition plate 5 near the inner periphery of the cylinders 6A and 6B. Second holes 12A, 1 that are in contact with each other and penetrate through
2B and a third hole provided so as to penetrate the partition plate 5 so that the respective second holes 12A and 12B are communicated with each other.
Hole 13 and the respective first holes 11A, 11 provided slidably in the respective second holes 12A, 12B.
First and second pistons 14A, 14B for opening and closing B
And these pistons 14A and 14B are connected to the respective first
The compression spring 15 is inserted through the third hole 13 formed in the partition plate 5 so as to urge the holes 11A and 11B in the valve opening direction.

The compression spring 15 pushes each of the first and second pistons 14A and 14B under the low pressure condition by its urging force.
1B is urged so as to maintain the valve open state, whereby the refrigerant gas G in the compression chamber 8A or 8B during the compression process is discharged from the first hole 11A or 11B to the third position.
Through the hole 13 of the compression chamber 8 during the other suction process.
The capacity control operation is performed by alternately flowing into A or 8B through the first hole 11A or 11B.

Then, in the vicinity of the inner circumference of each of the cylinders 6A, 6B, the first and second pistons 14A, 1
Second holes 12A, 12 on the piston head side of each of 4B
A back pressure space 16 communicating with B is formed, and a high pressure back pressure medium P is flown into the back pressure space 16 from an inflow pipe 17 which is exposed from the outer side portion 1b of the hermetically sealed container 1. , The first and second pistons 14A and 14B are moved against the biasing force of the compression spring 15 to move the first and second first holes 11A and 11B, respectively.
B is closed and the capacity control operation is stopped.

[0006]

However, in the above-mentioned conventional hermetic rotary compressor, in particular, the structure of the displacement control mechanism 10, the compression spring 15 serving as a driving force for operating the displacement control pistons 14A and 14B. Is inserted into the third hole 13 formed through the partition plate 5 in a loosely inserted state,
Moreover, since the upper and lower pistons 14A and 14B are operated integrally, the total length of the compression spring 15 becomes long, and the compression control is stopped when the capacity control operation is performed when the pistons 14A and 14B are operated by back pressure. Spring 15
Is compressed and shortened, the compression spring 15 is distorted (bent). Due to such distortion (bent) of the compression spring 15, the peripheral surface of the insertion portion of the compression spring 15 into the third hole 13 of the partition plate 5 is surrounded. However, the inner peripheral side surface of the third hole 13 of the partition plate 5 is likely to come into contact with the inner peripheral surface of the third hole 13, and troubles such as wear and breakage are likely to occur.

Moreover, conventionally, each of the pistons 1 is
The back pressure applied to 4A, 14B is connected to the high pressure side refrigerant gas piping system branched from the middle of the refrigerant unit circuit, so that the gas pressure of the high pressure side refrigerant gas is used as the back pressure medium P. For the second holes 12A and 12B,
If the gap between the pistons 14A and 14B sliding in the second holes 12A and 12B is not made as small as possible, the back pressure medium P leaks into the compression chambers 8A and 8B, and the pressurizing pressure is increased. When the displacement control operation is stopped, each piston 14A, 14B loses the urging force (repulsive force) of the compression spring 15 to operate unnecessarily, and also has a problem of reducing compression efficiency.

An object of the present invention is to provide a hermetic rotary compressor capable of preventing troubles due to wear and breakage of a compression spring driving a piston of a displacement control mechanism and reduction of compression efficiency. Especially.

[0009]

In order to solve the above-mentioned problems, the present invention has a rotary compression element driven by a crankshaft of an electric element housed in a hermetically sealed container in two stages via a partition plate. The first and second cylinders are divided into two parts, and the refrigerant gas alternately supplied in the compression chambers of these cylinders is compressed and discharged to the external refrigerant unit circuit. A capacity control mechanism provided in the element for controlling the capacity of the compression chamber, and a first hole communicating with each of the compression chambers provided on the side walls of the first and second cylinders in the outer peripheral direction, respectively, and Second holes penetrating each other in the vicinity of the inner circumference of each of the cylinders so as to communicate with the first holes with the partition plate interposed therebetween in the direction of the rotation axis of the crankshaft, and the second holes respectively penetrating therethrough. The second holes of the two communicate with each other A third hole penetrating the partition plate as described above, and first and second pistons for opening and closing the first holes slidably provided in the second holes, respectively. , A hermetically sealed rotary compression constituted by a compression spring provided by inserting the both pistons into a third hole formed in the partition plate so as to urge the pistons in the valve opening direction of each of the first holes. In the machine, the intermediate portion of the compression spring of the capacity control mechanism is held in the third hole of the partition plate.

In the above structure, the intermediate portion of the compression spring of the capacity control mechanism is composed of a large-diameter spiral portion, and the intermediate spiral portion is formed on the inner peripheral side surface of the third hole of the partition plate. It is characterized in that it is screwed onto and held.

Further, the present invention is characterized in that the lubricating oil stored in the oil reservoir on the inner bottom surface of the closed container is connected to the refrigerant unit circuit so as to serve as a back pressure medium. .

Further, the present invention is characterized in that lubricating oil stored in an oil separator connected to the high pressure side of the refrigerant unit circuit is used as a back pressure medium.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below in detail with reference to the drawings shown in FIGS. In the illustrated embodiment of the present invention, portions having the same configurations as those of the conventional structure shown in FIGS. 6 to 8 will be described using the same reference numerals.

1 to 4 show a first embodiment of a hermetic rotary compressor according to the present invention, which is basically the same as the conventional structure shown in FIG. It has an overall structure.

That is, the electric element 2 is provided in the closed container 1,
The rotary compression element 4 driven by the crankshaft 3 of the electric element 2 is housed, and the inner bottom surface of the closed container 1 is supplied with the lubricating oil O supplied to the drive parts of the electric element 2 and the rotary compression element 4. The first and second parts are divided into upper and lower parts by a partition plate 5 as the rotary compression element 4 while forming the oil sump portion 1A.
Piston rollers 7A provided in the cylinders 6A, 6B of
7B are alternately eccentrically rotated by the crankshaft 3 of the electric element 2, and the compression chambers 8A, 8B formed by the cylinders 6A, 6B and the piston rollers 7A, 7B are placed in one of the closed containers 1 Suction pipe 9 facing from the outer side 1a side
Refrigerant gas G is alternately supplied through A, and the refrigerant gas G compressed while repeating the suction / compression process is provided on the top of the closed container 1 and has an external refrigerant unit circuit 20 described later.
And a capacity control mechanism 10 for controlling the capacity of the rotary compression element 4 on the other outer side 1b side of the closed container 1.

As shown in FIG. 1, such a capacity control mechanism 10 includes compression chambers 8A, 8A, 6B, 6A, 6B provided on the side walls of the first and second cylinders 6A, 6B in the outer peripheral direction, respectively.
8B and the first holes 11A and 11B communicating with each other, and the partition plates 5 in the vicinity of the inner circumferences of the cylinders 6A and 6B so as to communicate with the first holes 11A and 11B. The second holes 12A, 12B which are opposed to each other in the direction of the rotation axis of the crankshaft 3 and penetrate therethrough, and the second holes 12A, 12B are penetrated through the partition plate 5 so as to communicate with each other. A first hole for opening and closing the third hole 13 provided and the respective first holes 11A, 11B slidably provided in the respective second holes 12A, 12B.
And the second pistons 14A and 14B, and the two pistons 14A and 14B to the first holes 11A and 11B, respectively.
The compression spring 15 is inserted through the third hole 13 formed in the partition plate 5 so as to bias the valve opening direction.

The compression spring 15 pushes each of the first and second pistons 14A and 14B under the low pressure condition by its urging force.
1B is urged so as to maintain the valve open state, whereby the refrigerant gas G in the compression chamber 8A or 8B during the compression process is discharged from the first hole 11A or 11B to the third position.
Through the hole 13 of the compression chamber 8 during the other suction process.
The capacity control operation is performed by alternately flowing into A or 8B through the first hole 11A or 11B.

Further, in the vicinity of the inner circumference of each of the cylinders 6A, 6B, the first and second pistons 14A, 14
Second holes 12A, 12B on the piston head side of each B
A back pressure space 16 communicating with the back pressure space 16 is formed, and a high pressure back pressure medium P is caused to flow into the back pressure space 16 from an inflow pipe 17 exposed from the outer portion 1b of the closed container 1.
As shown in FIG. 2, each of the first and second pistons 14A and 14B is moved against the biasing force of the compression spring 15, thereby causing each of the first holes 11 to move.
The valves A and 11B are closed and the capacity control operation is stopped.

Further, as shown in FIG. 3, the intermediate portion of the compression spring 15 of the capacity control mechanism 10 is formed into a large-diameter spiral portion 15a, which is the third spiral portion of the partition plate 5. Screwing portion 13 formed on the inner peripheral side surface of the hole 13 of
It is configured to be held by being screwed into a.

As shown in FIG. 4, reference numeral 20 in the drawing denotes a refrigerant unit circuit connected to the outside of the hermetic rotary compressor, and this refrigerant unit circuit 20 extends from the discharge pipe 9B of the child hermetic container 1. The discharged refrigerant gas is condensed by the condenser 21.
And the refrigerant gas after heat exchange to the evaporator 23 via the expansion mechanism 22 and to the rotary compression element 4 via the suction pipe 9B, and branched to the downstream side of the evaporator 23. The branch refrigerant circuit 20A is connected to the inflow pipe 17 of the capacity control mechanism 10 via the pressure reducing solenoid valve 24, and
The oil reservoir 1A at the inner bottom of the closed container 1 is communicated to the downstream side of the back pressure circuit 20B which is branched from the pressure reducing electromagnetic valve 24 and the inflow pipe 17 via the pressure increasing electromagnetic valve 25. By connecting the outflow pipe 18, the lubricating oil O stored in the oil reservoir 1A of the closed container 1 serves as a back pressure medium P.

FIG. 5 shows a back pressure circuit according to a second embodiment of the present invention, in which the refrigerant unit circuit 2 is provided.
The lubricating oil O stored in the inner bottom portion of the oil separator 27 connected to the pressure reducing capillary tube 26 is used as the back pressure medium P.

[0022]

As is apparent from the above description, according to the present invention, the rotary compression element driven by the crankshaft of the electric element housed in the closed container is divided into two stages through the partition plate. The first and second cylinders are formed, and the refrigerant gas alternately supplied in the compression chambers of these cylinders is compressed and discharged to the external refrigerant unit circuit. A capacity control mechanism for controlling the capacity of the chamber is communicated with a first hole that communicates with each compression chamber provided in the outer circumferential side walls of the first and second cylinders, and with each of these first holes. As described above, the second holes penetrating each other in the vicinity of the inner circumference of each cylinder through the partition plate so as to be opposed to each other in the direction of the rotation axis of the crankshaft and the respective second holes communicate with each other. No. 3 which is provided by penetrating the partition plate The first and second opening and closing the hole, the first hole of each respectively provided slidably on the second hole of each
Sealed rotation including a piston and a compression spring inserted through a third hole formed in the partition plate so as to urge both pistons in the valve opening direction of each first hole. In the compressor, since the intermediate portion of the compression spring of the capacity control mechanism is held in the third hole of the partition plate, the conventional problems such as wear and breakage due to distortion (bending) of the compression spring occur. Can be prevented.

Moreover, in claim 2, the intermediate portion of the compression spring is formed into a large-diameter spiral portion, and the intermediate spiral portion is screwed into the screwing portion formed on the inner peripheral side surface of the third hole of the partition plate. Since they are held together, the compression springs can be integrally formed as in the past, which makes it possible to optimize each cylinder and the piston roller, crankshaft, etc. incorporated in each cylinder. It is possible to easily assemble the compression spring later without hindering the assembly while ensuring a sufficient clearance.

Further, in claim 3, the lubricating oil stored in the oil sump portion on the inner bottom surface of the closed container is connected to the refrigerant unit circuit so as to serve as a back pressure medium. Compared with what becomes a pressure medium,
The gap between the second hole and the piston can be increased, which can reduce the machining accuracy between the two portions, thus reducing the machining cost.

Further, in claim 4, since the lubricating oil stored in the oil separator connected to the high pressure side of the refrigerant unit circuit serves as a back pressure medium, it is incorporated in the refrigerant unit circuit side when assembling the refrigerant unit. Since the solenoid valve of the capacity control mechanism and the pressurizing oil supply circuit can be connected to the refrigerant unit circuit side first, the number of connecting pipes between the refrigerant unit circuit and the compressor body can be reduced. As a result, the number of assembling steps can be reduced, and it is not necessary to take out oil from the compressor body, so that the price can be reduced.

[Brief description of the drawings]

FIG. 1 is an enlarged cross-sectional view of a main part of a hermetic rotary compressor according to a first embodiment of the present invention during a capacity control operation of a capacity control mechanism for a rotary compression element.

FIG. 2 is an enlarged sectional view of an essential part showing a piston operating state when the displacement control operation of the displacement control mechanism of the rotary compression element is stopped.

FIG. 3 is an enlarged cross-sectional view of a main part of a portion A of FIG.

FIG. 4 is an explanatory view showing a connection state to the refrigerant unit circuit in the same manner.

FIG. 5 is an explanatory diagram of a connection state to a refrigerant unit circuit showing a second embodiment according to the present invention.

FIG. 6 is a sectional view of the entire configuration of a conventional hermetic rotary compressor.

FIG. 7 is an enlarged cross-sectional view of a main part of the conventional rotary compression element during capacity control operation of the rotary compression element capacity control mechanism.

FIG. 8 is an enlarged sectional view of an essential part showing a piston operating state when the capacity control operation of the conventional rotary compression element capacity control mechanism is stopped.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Airtight container, 1a, 1b ... Outer side part, 1A ... Oil sump part, 2 ... Electric element, 3 ... Crank shaft, 4 ... Rotary compression element, 5 ... Partition plate, 6A, 6B ... Cylinder, 7A, 7B ... Piston roller, 8A, 8B ... Compression chamber, 9A ... Suction pipe, 9B ... Discharge pipe, 10 ... Volume control mechanism , 11A, 11B ... First hole, 12A, 12B ... Second hole, 13 ... Third hole, 13a ... Inner peripheral side surface (screwed portion), 14A, 14B ... -Piston, 15 ... Compression spring, 15a ... Intermediate spiral part, 16 ... Back pressure space, 17 ... Inflow pipe, 18 ... Outflow pipe, 20 ... Refrigerant unit circuit, G ... ..Refrigerant gas, P ... Back pressure medium, O ... Lubricating oil.

Claims (4)

[Claims] 1. A rotary compression element driven by a crankshaft of an electric element housed in a hermetically sealed container, and a rotary compression element 2
It is formed by first and second cylinders divided into stages, and the refrigerant gas alternately supplied in the compression chambers of these cylinders is compressed and discharged to an external refrigerant unit circuit. A capacity control mechanism provided in a compression element for controlling the capacity of the compression chamber, and a first hole that communicates with each compression chamber provided on the side walls of the first and second cylinders in the outer peripheral direction, and a first hole that communicates with the first hole. Second holes penetrating each other in the rotation axis direction of the crankshaft in the vicinity of the inner periphery of each of the cylinders so as to communicate with the first holes of the cylinders with the partition plate interposed therebetween, and Opening and closing of a third hole penetrating the partition plate so that the respective second holes communicate with each other and each first hole slidably provided in each of the second holes. First and second pistons,
A hermetic rotary compressor composed of a compression spring inserted into a third hole formed in the partition plate so as to urge both pistons in the valve opening direction of each of the first holes. 3. The hermetic rotary compressor according to claim 3, wherein an intermediate portion of the compression spring of the capacity control mechanism is held in the third hole of the partition plate. 2. The intermediate portion of the compression spring of the capacity control mechanism comprises a large-diameter spiral portion, and the intermediate spiral portion is screwed into a screwing portion formed on the inner peripheral side surface of the third hole of the partition plate. The hermetically sealed rotary compressor according to claim 1, wherein the hermetically sealed rotary compressor is held. 3. The hermetically sealed rotary according to claim 1, wherein the lubricating oil stored in the oil sump portion on the inner bottom surface of the hermetic container is connected to the refrigerant unit circuit so as to serve as a back pressure medium. Compressor. 4. The hermetic rotary compressor according to claim 1, wherein the lubricating oil stored in an oil separator connected to the high pressure side of the refrigerant unit circuit is used as a back pressure medium.