JPH01247786A - Two-cylinder type rotary compressor - Google Patents

Abstract

PURPOSE:To make fruitless compression work zero and improve capacity variable efficiency by a method wherein a blade of a cylinder chamber is forcedly kept off a roller and a high pressure feeding device which suspends compression function by making the pressure of a cylinder chamber high is provided. CONSTITUTION:Cylinder chambers 7a, 8a re equipped with compression mechanisms 9a, 9b. A high pressure feeding device 25 is provided only on the first cylinder 7a. A hole for feeding high pressure 26 is provided at a position which is closed by the upper end of a blade 11a during normal operation and which is opened when it is applied with force so that this blade 11a is forcedly separated from a roller 10a. This makes fruitless compression work zero, improving capacity variable efficiency.

Description

Detailed Description of the Invention (Objective of the Invention) (Industrial Field of Application) The present invention has a cylinder chamber of 2V, performs a compression action at the same time in both chambers, and interrupts the compression action in one of the cylinder chambers. The present invention relates to a two-cylinder rotary compressor that can reduce compression work and achieve so-called variable capacity.

(Prior art) There is a tendency for two-cylinder rotary compressors to be frequently used, which are equipped with two cylinder chambers, one for the passenger and one for the passenger, in a closed container, and each cylinder chamber is equipped with a compression mechanism to perform compression at the same time. It is in. That is, this type of compressor is advantageous because it can perform the compression work of two compressors in the space of one compressor.

Moreover, if the compression action in one of the cylinder chambers is interrupted and the compression action in the other cylinder chamber is continued, the compression work will be halved, making it possible to perform so-called variable capacity.

In order to make such variable capacity possible, a refrigeration cycle equipped with this type of compressor has conventionally been constructed as shown in FIG. 4. In the figure, reference numeral 1 denotes a two-cylinder rotary compressor (hereinafter simply referred to as a compressor), which includes a condenser, a 2° throttling mechanism, 3. Evaporator 4. The gas-liquid separator 5 is sequentially connected via the refrigerant pipe P. The compressor 1 is
A first cylinder 7 and a second cylinder 8 are placed in a closed container 6.
Equipped with. These cylinders 7.8 are actually located one above the other around an axis of rotation, which is not shown, with intermediate partitions interposed therebetween. The first, which is inside each cylinder 7°8
The cylinder chamber 7a and the second cylinder chamber 8a are provided with a pressure #I mechanism 98.9b having the same configuration. That is, 1st. The second cylinder chambers 7a, 8a accommodate rollers 10a, 10b that are fitted onto the eccentric portion of the rotating shaft, and blades 11 are provided on the circumferential surfaces of the respective rollers 10a, 10b.
The tips of a and 11b elastically abut each cylinder chamber 7.
a, partition 8a. Springs 12a, 12b that elastically press and bias the blades 11a, Ilb are blade chambers 13a, 1 integrally provided in each cylinder 7.8.
3b. On the other hand, the first. Second cylinder7.
A discharge hole 1 is provided on one side of the blades 11a and llb in 8.
4a.

14b is provided, and the discharge valves 15a and 15b are connected to rM.
l! Il is designed to do so. The discharge valve 15a.

By opening 15b, the cylinder chamber 7a is opened.

The refrigerant gas compressed within 8a is discharged and guided into the closed container 6. Suction holes 16a and 16b are opened on the other side of the blades 11a and 11b, and refrigerant pipes P and P passing through the closed container 6 are connected to the suction holes 16a and 16b, respectively. These refrigerant pipes P and P on the suction side join together on the refrigerant outlet side of the gas-liquid separator 5,
Only the refrigerant pipe P communicating with the first cylinder chamber 7a is provided with a 1vA on-off valve 17 in the middle.

To perform normal two-cylinder operation, the electromagnetic on-off valve 17 is opened and the rotating shaft of the compressor 1 is driven to rotate.

1st. Second cylinder chamber 7a.

Rollers 10a and 10b in roller 8a rotate eccentrically at the same time, and blades 11a and 11b follow this movement to partition the inside of cylinder chambers 7a and 8a. Through these operations, refrigerant gas is sucked into each cylinder chamber 7a, 8a via the refrigerant pipes P, P on the suction side, compressed, and discharged into the closed container 6. The high temperature and high pressure refrigerant gas is then transferred to the condenser 2. Aperture mechanism 3. Evaporator 4. The gas-liquid separators 5 are successively connected to perform a refrigeration cycle.

To perform variable capacity operation, the electromagnetic on-off valve 17 is closed.

Refrigerant gas is not sucked into the first cylinder chamber 7a, but is drawn into the second cylinder chamber 7a.
The compressed air is sucked only into the cylinder chamber 8a, and a compression action is performed. In the first cylinder chamber 7a, the roller 10a continues to rotate, but there is no compression action, resulting in so-called idle operation. In the end, it is possible to change the capacity by halving the compression work while continuing the operation of compression 1i11.

(Problem to be Solved by the Invention) However, in such a compressor, compressed high-pressure refrigerant gas is always discharged into the closed container 6 regardless of normal operation or variable capacity operation. The pressure inside is high. On the other hand, since the pressure inside the cylinder chamber (here, the first cylinder chamber 7a) which operates empty during the variable capacity operation is low pressure, the high pressure refrigerant gas inside the closed container 6 and the lubricating oil contained therein The discharge valve 15a and the discharge hole 14a
or from around the blade 11a into the first cylinder chamber 7a. Therefore, the first cylinder chamber 7
In case a, the compression work could not be completely reduced to zero, and the capacity variable efficiency was poor.

The present invention has been made by focusing on the situation described in F. By increasing the pressure of the cylinder chamber that operates empty when the capacity is varied, the compression work in this cylinder chamber is completely reduced to zero, and the efficiency of the variable capacity is reduced. The purpose of the present invention is to provide a two-cylinder rotary compressor that can be improved.

(Structure of the Invention) (Means for Solving the Problems) That is, the present invention provides a roller that rotates eccentrically in each of the two cylinder chambers, and a blade that elastically abuts around the roller and partitions the cylinder chamber. In a device that is equipped with a compression mechanism that compresses two cylinder chambers at the same time, if necessary, the blade of one of the cylinder chambers is forcibly held apart from the roller, and the pressure of that cylinder chamber is increased to perform compression. This is a two-cylinder rotary compressor characterized by being equipped with a high-pressure introducing means for interrupting.

(Function) The blade is separated from the roller by the action of the high pressure introduction means, and the pressure in the cylinder chamber is increased, so that the compression work in the cylinder chamber becomes completely zero.

<Example> Hereinafter, an example of the present invention will be described based on FIGS. 1 and 2. R in the figure is a 2-cylinder type rotary compression 8! (hereinafter simply referred to as a compressor), which includes a condenser 2, a two-stage throttling mechanism 21. Evaporator 4
．． The gas-liquid separator 5 is sequentially connected via the refrigerant pipe P. The compressor R has an intermediate partition plate 2 in a closed container 6, as in the conventional case.
2, a first cylinder 7 and a second cylinder 8 are provided above and below each other. The upper surface opening of the first cylinder 7 is closed by the main bearing 23, and the upper surface opening of the first cylinder 7 is closed by the main bearing 23.
The lower opening of is closed by a sub bearing 24. In addition, each cylinder chamber 7a, 8a has a compression mechanism 9 similar to the conventional one.
9a and 9b, the same numbers are given to the respective constituent parts and the explanation thereof will be omitted.

High pressure introducing means 25 is provided only in the first cylinder chamber 7a. That is, it is a part of the main bearing 23,
A high pressure introduction hole 26 is provided at a position that is closed at the upper end surface of the blade 11a under normal operating conditions and opens when the blade 11a is forcibly urged away from the roller 10a. By opening this high pressure introduction hole 26, the first cylinder chamber 7a and the inside of the closed container 6 are brought into direct communication. Further, the spring 12a that imparts elastic force to the blade 11a is housed in the blade chamber 3a as in the conventional case, but this blade chamber 13a and the first throttle mechanism 21a constituting the two-stage throttle mechanism 21 are connected to each other. The intermediate part between the throttle mechanism 21b and the bypass refrigerant pipe p
communicated by a. An electromagnetic on-off valve 27 is provided in the middle of this bypass refrigerant pipe Pa. Furthermore, the first
A check valve 28 for blocking the flow of refrigerant from the first cylinder chamber 7a to the gas-liquid separator 5 is provided in the middle of the suction side refrigerant pipe P connected to the cylinder 7.

For normal two-cylinder operation, it is sufficient to close the electromagnetic on-off valve 27 and drive the compression IIR. 1st
．． Rollers 10a, 10 in second cylinder chambers 7a, 8a
b rotates eccentrically at the same time, and this movement causes the blade 118.1
1b follows and partitions the inside of the cylinder chambers 7a and Ba. These operations cause a refrigerant pipe P on the suction side to each cylinder chamber 7a, 8a.

Refrigerant gas is sucked in through P and compressed into a closed container 6.
discharged inside. The high-pressure refrigerant gas is then transferred to a condenser 2, a two-stage throttling mechanism 21. Evaporator 4. Gas-liquid separator 5
are sequentially communicated to perform a refrigeration cycle, and then sucked into each cylinder chamber 7a, 8a again.

To achieve variable capacity operation, the high pressure introduction means 25 is activated. That is, the electromagnetic on-off valve 27 is opened and the bypass refrigerant pipe p
A refrigerant is introduced into the blade chamber 13a through a. The refrigerant introduced here is a part of the refrigerant that passed through the first throttle mechanism 218 of the two-stage throttle mechanism 21, and has an intermediate pressure P2 that has not been completely reduced in pressure. On the other hand, the cylinder chamber 7a
Since the compression action continues in , the cylinder chamber 7a is at high pressure P1. These pressure differences (ΔP-P1
-P2) k: Therefore, the blade 11a is forcibly pushed into the blade chamber 13a side, and the high pressure introduction hole 26 is opened. Then, the high-pressure refrigerant gas discharged into the closed container 6 is introduced into the first cylinder chamber 7a through the high-pressure introduction hole 26 and continues to be pressurized. Blade 11a is roller 10a
Although the rollers 10a continue to rotate, there is no compression effect, resulting in so-called idle operation. The high-pressure refrigerant gas in the cylinder 17a is led out from the suction-side refrigerant pipe P toward the gas-liquid separator 5, but its flow is blocked by a check valve 28 provided in the middle. In the end, it is possible to change the capacity by reducing the compression work by half while the compressor R continues to operate.

Note that a high pressure introducing means 25A as shown in FIG. 3 may be used. That is, the compression 11R itself is completely the same as in the above embodiment, and the same numbers will be given and new explanation will be omitted. Furthermore, this blade chamber 13a and the first aperture forming a two-stage aperture m-ellipse! An intermediate product between the I structure 21a and the second throttle structure 21b is communicated with by a bypass refrigerant pipe pa,
Similarly, an electromagnetic on-off valve 27 is provided in the middle of the valve. On the other hand, a second electromagnetic on-off valve 31 is provided in the middle of the suction side refrigerant pipe P connected to the cylinder 7. Further, a high pressure introduction refrigerant pipe pb branches from between this second electromagnetic on-off valve 31 and the compressor R, and this end is connected to the compression tII.
R and the condenser 2 are connected to a discharge side refrigerant pipe P that communicates with the condenser 2.

A third electromagnetic on-off valve 32 is provided in the middle of the high-pressure introduction refrigerant pipe Pb.

Thus, during normal operation, the second *11i closing valve 31 is opened and the third electromagnetic opening/closing valve 32 is closed.

Of course, the electromagnetic on-off valve 27 is closed, and performs the same refrigeration cycle operation as in the above embodiment.

To achieve variable capacity operation, the pressure introduction means 27 is operated. That is, after opening the electromagnetic on-off valve 27 and conducting the first throttling mechanism 21a, the intermediate pressure refrigerant is transferred to the blade chamber 13a.
In addition to introducing the second N! & The on-off valve 31 is closed, and the third electromagnetic on-off valve 32 is opened. Therefore, a part of the high-pressure refrigerant gas discharged from the discharge-side refrigerant pipe P is introduced into the first cylinder chamber 7a via the third electromagnetic on-off valve 32, and this cylinder chamber 7atfi^ pressure is increased to high pressure. The introduction hole 26 is opened to obtain the same effect as in the above embodiment.

(Parts that are the same as those in the above embodiment are given the same numbers and new explanations are omitted.) In addition, the configuration of the high pressure introducing means can be prepared in various ways, and modifications can be made within the scope of the gist of the present invention. It is.

〔Effect of the invention〕

As explained above, according to the present invention, empty operation can be performed with one cylinder chamber under high pressure by the high pressure introduction means, and refrigerant gas and lubricating oil do not leak into this cylinder chamber.
This has the effect of completely eliminating unnecessary compression work and improving variable capacity efficiency.

[Brief explanation of the drawing]

1 and 2 show an embodiment of the present invention, FIG. 1 is a schematic structure of a two-cylinder rotary compressor and a block diagram of a refrigeration cycle equipped with this compressor, and FIG. 2 is a two-cylinder rotary compressor. FIG. 3 is a longitudinal cross-sectional view of a main part of a two-cylinder rotary compressor showing another embodiment of the present invention, and a block diagram of a refrigeration cycle equipped with this compressor. The figure is a schematic structure of a two-cylinder rotary compressor and a configuration diagram of a refrigeration cycle equipped with this compressor, showing a conventional example of the present invention. 7a... (first) cylinder chamber, 8a... (second) cylinder chamber, 10a, 10b... roller, 11a. 11b...Blade, 9a, 9b...Compression mechanism, 2
5... High pressure introduction means. Applicant's agent Patent attorney Takehiko Suzue Figure 1

Claims (1)

[Claims] Equipped with two cylinder chambers, each cylinder chamber is equipped with a compression mechanism consisting of a roller that rotates eccentrically and a blade that elastically contacts the circumferential surface of this roller to partition the cylinder chambers, which simultaneously compresses the two cylinder chambers. characterized by comprising high pressure introducing means for forcibly holding the blades of one of the cylinder chambers apart from the rollers and increasing the pressure of the cylinder chamber to interrupt the compression action as necessary. A 2-cylinder rotary compressor.