JP2914702B2 - Multi-cylinder rotary compressor - Google Patents

Description

Description: Object of the Invention (Industrial Application Field) The present invention relates to a multi-cylinder rotary compressor having a plurality of compression mechanisms built in a closed casing, and in particular, to a release for adjusting a compression capacity. The present invention relates to a multi-cylinder rotary compressor having an improved mechanism.

(Prior Art) Conventionally, in this type of multi-cylinder rotary compressor, a release mechanism is provided for varying the compression capacity.
One example is described in JP-A-61-272492.

The multi-cylinder rotary compressor 1 has, as shown in a vertical sectional view of a main part in FIG. 7, a first and a second cylinder 3, 4 of two compression mechanisms arranged vertically in a closed casing 2, for example. And an intermediate partition plate 5 is interposed between the cylinders 3 and 4.

The intermediate partition plate 5 slidably accommodates a slide valve 7 in a valve guide hole 6 and a high-pressure chamber 8 of the first cylinder 3.
And a low pressure chamber 9 of the second cylinder 4 are respectively formed with communication holes 10 vertically communicating with each other to form a release passage, and the communication hole 10 is opened by the slide valve 7 to perform the release operation. Has become.

(Problems to be Solved by the Invention) However, in such a conventional multi-cylinder rotary compressor 1, since the gas pressure of the gas discharged from the compression mechanism is used as a drive source of the slide valve 7, the valve guide hole 6 is used. The pipe 11 is connected to first and second bypass pipes 12, 13 as shown in FIG.

For this reason, there is a problem that the piping becomes complicated, the amount of piping is increased, the number of parts such as the two-way valves 14 and 15 is increased, and the cost is increased.

In addition, since the slide valve 7 and the spring 16 are built in the valve guide hole 6 and the thickness of the intermediate partition plate 5 increases,
There is a problem that the bearing load for supporting 17 increases and the shaft reliability decreases.

In FIG. 7, reference numeral 18 denotes a main bearing, 19 denotes a sub bearing, and 20 and 21 denote rollers.
Is a condenser, and 23 is an evaporator.

Therefore, the present invention has been made in view of the above circumstances,
It is an object of the present invention to provide a multi-cylinder rotary compressor in which the release mechanism has a simple configuration, operates reliably, and can reduce the cost.

[Configuration of the invention]

(Means for Solving the Problems) The present invention is configured as follows to solve the above problems.

That is, the invention according to claim 1 is a multi-cylinder rotary compressor in which a plurality of compression mechanisms are housed in a closed casing, wherein an intermediate partition plate formed by joining a plurality of plate members to partition between adjacent cylinders; A release passage formed in the intermediate partition and communicating the high-pressure chamber of one cylinder and the low-pressure chamber of the other cylinder; and a cross-sectional rectangle formed between a plurality of plate members of the intermediate partition perpendicular to the release passage. A movable valve that has a U-shaped valve body that is reciprocally movable within the valve guide passage and that opens and closes the release passage, and that constantly receives pressure in a direction that closes the release passage; A multi-cylinder rotary compressor comprising an electromagnet for moving a valve by electromagnetic force to open the release passage.

According to a second aspect of the present invention, the valve body driving means includes an electromagnet provided with a magnet on the movable valve and moving the magnet by electromagnetic force to open the release passage. Machine.

(Operation) During the normal operation in which the release operation is not performed, the pressure in the closed casing is applied to the U-shaped valve body, and this valve body is constantly urged to the closed position for closing the release passage.

However, at the time of the release operation, the movable valve is moved to the open position by the electromagnet of the valve body driving means to open the release passage.

For this reason, the compressed gas in the middle of the compression in the high-pressure chamber of one cylinder is released to the low-pressure chamber of the other cylinder, so that the capacity is reduced.

This allows the compression mechanism to operate at low capacity,
The lower limit of the low capacity can be expanded, and the capacity control can be performed according to the load fluctuation.

Therefore, according to the present invention, by forming the intermediate partition plate by joining a plurality of plate members, the valve guide passage is formed in a rectangular cross section, and the movable valve that opens and closes the release passage is a U-shaped valve body. Since it is formed, it is possible to prevent the thickness of the intermediate partition plate from increasing, and to always apply a pressure in a direction to close the release passage to the movable valve and move the movable valve by electromagnetic force to release the release passage. By providing the valve drive means for opening the pipe, it is possible to prevent the pipe from becoming complicated and the pipe pulling amount from increasing.

Embodiment An embodiment of the present invention will be described below with reference to FIGS.

FIG. 3 is a longitudinal sectional view of one embodiment of the present invention. In the drawing, a multi-cylinder rotary compressor 31 includes a motor unit 33 and, for example, two first and second compression mechanisms in a closed casing 32. 34,35
The compressed gas is discharged from the compression mechanisms 34 and 35 into the closed casing 32 and then discharged to the outside by the discharge pipe 36.

The first and second compression mechanisms 34 and 35 are arranged in two upper and lower stages in the figure, and are rotationally driven by the rotation shaft 33a of the motor unit 33, and their rotation phase angles are shifted from each other by, for example, 180 °.

Therefore, the inside of the cylinder 37 of the first compression mechanism 34 is
In the case of 37a, the inside of the cylinder 38 of the second compression mechanism 35 is in the low pressure chamber 38a.
Becomes

An intermediate partition plate 39 is interposed between these cylinders 37 and 38.

As shown in FIG. 4, the intermediate partition plate 39 is composed of a thin disk-shaped upper partition plate 40 and a thick disk-shaped lower partition plate 41, which are a plurality of plate members, as shown in FIG. Shaft holes 40a, 41a through which the rotating shaft 33a is rotatably inserted.
Are drilled respectively.

The lower partition plate 41 has a lateral groove 41b of a required width, which is a valve guide passage, formed in the radial direction on the upper surface in the drawing, and the inner end thereof is formed into a shaft hole 40a through a pressure equalizing hole 41c smaller in width than the lateral groove 41b. They are communicating.

The horizontal axis 41b has a lower hole 41d formed on the bottom thereof so as to penetrate the lower partition plate 41 in the thickness direction.

On the other hand, the upper partition plate 40 is provided with an upper hole 40b penetrating in the thickness direction thereof at a position corresponding to the lower hole 41d, and as shown by a broken line in FIG. 41d communicates via the space of the lateral groove 41b to form a release passage 42.

A movable valve 43 shown in FIG. 6 is accommodated in the lateral groove 41b so as to be reciprocally movable in the radial direction. The movable valve 43 is a valve body 44 formed by bending a flat plate into a U-shape along the vertical direction in the figure. The upper hole 40b of the intermediate partition plate 39 is airtightly closed by the upper surface 44a, and the lower surface 44b
Thereby, the lower hole 41c is airtightly closed.

A round rod-shaped valve stem 45 is fixed to the U-shaped arc portion of the valve body 44, and a cylindrical magnet 46 is externally fitted and fixed to the outer periphery of the distal end portion of the valve stem 45. A narrow groove 46a penetrating in the axial direction is formed.

The magnet 46 extends radially from the outer surface opening 41e of the lateral groove 41b of the intermediate partition plate 39, as shown in FIGS. 1 and 2, and further extends through the closed casing 32 into the cap 47. I have.

The cap 47 is formed in a cylindrical shape with a bottom by a non-magnetic material,
The opening end is fitted and fixed in the through hole of the closed casing 32, and an electromagnet 48 is arranged on the outer peripheral surface of the cap 47 in the circumferential direction.

The electromagnet 48 is connected to a power supply 50 via a switch 49,
When the switch 49 is turned on, it is excited and attracts the magnet 46 of the movable valve 43 as shown in FIG.
And the valve drive mechanism is configured to open the high pressure chamber 37a of the first cylinder and the low pressure chamber 38a of the second cylinder.

 Next, the operation of the present embodiment will be described.

First, when the motor unit 33 rotates during the normal operation in which the release operation is not performed, the rotational force is given to the first and second compression mechanisms 34 and 35 via the rotation shaft 33a, respectively.
Drive these.

During the non-release operation, the switch 49 is shut off as shown in FIG. 1, so the electromagnet 48 is not excited,
The magnet 46 of the movable valve 43 is magnetically attracted to the closed casing 32 made of a magnetic material rather than the bottom of the cap 47 made of a non-magnetic material, and the U-shaped valve body 44 is pushed into the lateral groove 41b to form a U-shaped valve. The upper hole 40b is airtightly closed by the upper surface 44a of the valve body 44, and the lower hole 41d of the intermediate partition plate 39 is airtightly closed by the lower surface 44b, so that the release passage 42 is closed.

Accordingly, each of the compression mechanisms 34 and 35 separately compresses the refrigerant or the like, discharges the compressed refrigerant into the closed casing 32 first, and then discharges the compressed refrigerant to the outside through the discharge pipe 36.

For this reason, the refrigerant gas discharged into the closed casing 32 enters the inside opening end of the cap 47 as shown in FIG. 1 and flows through the narrow groove 46a of the magnet 46 to the left side of the magnet 46 in the figure. And equalize the left and right ends of the magnet 46 in the axial direction.
Can suck the closed casing 32 and move to the right in the figure.

On the other hand, on both sides of the movable valve 43 in the moving direction of the U-shaped valve body 44, the differential pressure in the closed casing 32 is pressurized from the outer opening 41e of the intermediate partition plate 39 and the equalizing hole 41c.

That is, the pressure Pda applied from the outer opening 41e and the pressure equalizing hole
Since the differential pressure of the pressure Pdb (Pda> Pdb) applied from 41c is applied to the U-shaped valve body 44, the U-shaped valve body 44 is always attached so as to be pushed inward in the lateral groove 41b. Be inspired.

That is, the U-shaped valve body 44 is constantly urged in a direction to close the release passage 42 by the magnetic attraction force of the magnet 46 to the closed casing 32 and the differential pressure between the discharge pressures PDa and PDb.

On the other hand, during the release operation, as shown in FIG. 2, the switch 49 is turned on and the electromagnet 48 is excited, so that the magnet 46 of the movable valve body 43 is magnetically attracted by the electromagnet 48, and the magnet 46 is moved to the bottom side of the cap 47. That is, it moves to the left side in the figure.

For this purpose, the U-shaped valve body 44 connected to the magnet 46 via the valve rod 45 slides in the lateral groove 41b toward the outer surface opening 41e against the pressure difference between the discharge gas pressure PDa and PDb. I do.

As a result, the upper and lower holes 41b and 41d of the intermediate partition plate 39 are opened, the release passage 42 is opened, and the high pressure chamber 37a of the first cylinder 37 and the second cylinder 38 are opened through the release passage 42.
Communicates with the low-pressure chamber 38a.

Therefore, the refrigerant gas in the middle of the compression in the high-pressure chamber 37a is released to the low-pressure chamber 38a, the capacity is reduced, and the capacity can be controlled according to the fluctuation of the load.

〔The invention's effect〕

As described above, the present invention provides an intermediate partition plate formed by joining a plurality of plate members to form a valve guide passage with a rectangular cross section and a movable valve that opens and closes a release passage. Since it is formed on the body, it is possible to prevent the thickness of the intermediate partition plate from increasing, and to apply pressure to the movable valve in a direction to always close the release passage, and to move the movable valve by electromagnetic force. By providing the valve drive means for opening the release passage, it is possible to prevent the pipe from becoming complicated and the pipe pulling amount from increasing.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a main part of a multi-cylinder rotary compressor according to an embodiment of the present invention, showing a release passage in a closed state, and FIG.
FIG. 3 is a longitudinal sectional view showing a main part of the embodiment of FIG. 1 in a closed state of the release passage, FIG. 3 is a longitudinal sectional view showing an entire configuration of the present embodiment including the principal parts shown in FIG. 1 and FIG. The figure is an exploded perspective view of the intermediate partition plate shown in FIG. 1 and the like, FIG. 5 is a longitudinal sectional view after the assembly of the intermediate partition plate shown in FIG. 4, and FIG. 6 is a perspective view of the movable valve shown in FIG. FIG. 7 is an enlarged longitudinal sectional view of a main part of a conventional release mechanism, and FIG. 8 is a refrigeration cycle diagram of a compressor having the release mechanism shown in FIG. 31: Multi-cylinder rotary compressor, 32: Sealed casing, 34
... first compression mechanism, 35 ... second compression mechanism, 37 ... first cylinder, 37a ... high-pressure chamber, 38 ... second cylinder, 38a
…… Low pressure chamber, 39 …… Intermediate partition plate, 40b …… Top hole, 41b…
... lateral groove, 41d ... lower hole, 42 ... release passage, 43 ...
Movable valve, 46 ... magnet, 48 ... electromagnet.

Claims (2)

(57) [Claims] 1. A multi-cylinder rotary compressor in which a plurality of compression mechanisms are housed in a closed casing, an intermediate partition plate formed by joining a plurality of plate members and separating adjacent cylinders; A release passage formed and communicating between the high-pressure chamber of one cylinder and the low-pressure chamber of the other cylinder, and a valve guide having a rectangular cross section formed between a plurality of plate members of the intermediate partition plate orthogonal to the release passage. A movable valve having a U-shaped valve body reciprocally movable within the valve guide passage for opening and closing the release passage, and a movable valve that constantly receives pressure in a direction to close the release passage; A multi-cylinder rotary compressor comprising: a valve drive means for moving the release passage by force. 2. The multi-cylinder rotary compressor according to claim 1, wherein said valve body driving means comprises an electromagnet provided with a magnet on a movable valve and moving said magnet by electromagnetic force to open said release passage.