JPH0225037B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a multi-cylinder rotary compressor in which a plurality of cylinders are partitioned by intermediate partition plates.

(Prior Art) A multi-cylinder rotary compressor, for example a two-cylinder compressor, is generally constructed as shown in FIG. That is, 1 is a case of a compressor, and a compressor main body 2 is housed within this case 1.
The compressor main body 2 is composed of an electric motor section 3 and a compressor section 4. The compressor section 4 is composed of a first cylinder 5 and a second cylinder 6,
An intermediate partition plate 7 is provided between these cylinders 5 and 6. Further, 8 is a shaft that interlocks with the electric motor section 3, and this shaft 8 is rotatably supported by a main bearing 9 and a sub-bearing 10. Eccentric portions 11 and 12 are provided at portions of the shaft 8 corresponding to the first cylinder 5 and the second cylinder 6, and the eccentric portions 11 and 12 are shifted in phase from each other.
2 has a first roller 13 and a second roller 14
are fitted. Further, a shaft portion 15 is provided between the eccentric portions 11 and 12 of the shaft 8, and this shaft portion 15 is rotatably supported by a bearing portion 16 of the intermediate partition plate 7.

The rotation of the shaft 8 causes the first roller 13 to eccentrically rotate within the first cylinder 5.
The second roller 14 rotates eccentrically within the second cylinder 6 to suck in, compress, and discharge refrigerant within an independent cylinder.

(Problems to be Solved by the Invention) Therefore, the above-mentioned multi-cylinder rotary compressor has the following problems:
Because the refrigerant is sucked in, compressed, and discharged in an independent cylinder, it is possible to increase the capacity compared to a normal single-cylinder rotary compressor, but the capacity is fixed and varies depending on the load. It is not possible to change the capacity.

This invention was made with attention to the above-mentioned circumstances, and its purpose is to make it possible to vary the capacity according to the load even in a rotary compressor that has a plurality of cylinders and each sucks and compresses independently. An object of the present invention is to provide a multi-cylinder rotary compressor.

(Means and Effects for Solving the Problems) In order to achieve the above object, the present invention provides an arrangement in which the high pressure chamber side of one adjacent cylinder and the low pressure chamber side of the other cylinder are located between the respective cylinders. This is achieved by providing an opening/closing mechanism that communicates with each other via a passage provided in the partition plate and opens and closes this passage. During normal operation, the passage is closed by the opening/closing mechanism, making both cylinders independent; when the capacity is down, the passage is opened by the opening/closing mechanism, and the high pressure chamber side of one cylinder is and the low pressure chamber side of the other cylinder,
Release reduces ability.

(Example) Hereinafter, an example of the present invention will be described based on the drawings.

Figure 1 shows the main parts of a multi-cylinder rotary compressor, and the basic configuration is the same as the conventional structure shown in Figure 4, so the same components will be given the same numbers and the explanation will be omitted. . In FIG. 1, 21 is an intermediate partition plate that partitions the first cylinder 5 and the second cylinder 6, and a valve guide hole 23 having a bottom portion 22 is bored in a part of the intermediate partition plate 21. ing. The bottom portion 22 has a sliding portion between the shaft portion 15 of the shaft 8 and the bearing portion 16, and a valve guide hole 23.
A pressure equalizing hole 24 communicating with the two is bored. Furthermore, a communication port 27 is bored in the intermediate partition plate 21 at a portion corresponding to the valve guide hole 23 as a passage for communicating the high pressure chamber 25 of the first cylinder 5 and the low pressure chamber 26 of the second cylinder 6. has been done. A slide valve 28 is housed in the valve guide hole 23 and is movable in the axial direction, closing the communication port 27 when moving forward and opening the communication port 27 when moving backward. It is always biased in the forward direction. Further, an opening/closing mechanism 30 for opening and closing the communication port 27 is configured. Further, one end of a pipe 31 is connected to the open end of the valve guide hole 23, so that back pressure is applied to the slide valve 28. That is, as shown in FIG. 2, the pipe 31 is branched and connected to the discharge side 32a of the multi-cylinder rotary compressor 32 via a bypass passage 33, and is connected to the suction side 32b via a bypass passage 34. It is connected. A first on-off valve 35 is provided in the bypass path 33, and a second on-off valve 36 is provided in the bypass path 34. Therefore, the first and second on-off valves 35 and 36
By switching the discharge side 3 to the pipe 31,
2a or the suction side 32b can be connected. In addition, 37 is a capacitor, 38 is an expansion valve,
39 is an evaporator.

During normal operation, the first on-off valve 35 is open and the second on-off valve 36 is closed, so that discharge pressure is applied to the valve guide hole 23 through the pipe 31. Therefore, the slide valve 28 is moved forward by the discharge pressure and the spring 29 to close the communication port 2.
7 is in the closed state. For this reason, the first cylinder 5
and the second cylinder 6 are completely independent. Next, when reducing the capacity, the first on-off valve 35 is closed, the second on-off valve 36 is opened, and the pipe 31 is communicated with the suction side 32b. As a result, high pressure is received from the pressure equalization hole 24, and the slide valve 28
moves backward against the restoring force of the spring 29. Therefore, the communication port 27 is in an open state, the high pressure chamber 25 of the first cylinder 5 and the low pressure chamber 26 of the second cylinder 6 communicate with each other, and the refrigerant gas in the middle of compression in the high pressure chamber 25 flows into the low pressure chamber 26. It will be released and the ability will be reduced. Therefore, capacity control can be performed in accordance with load fluctuations.

Note that in the above embodiment, the bypass path 3
3 and 34 are provided with on-off valves 35 and 36, respectively, but the present invention is not limited to this, and as shown in FIG.
A three-way valve 40 may be provided at the connection portion with the bypass paths 33, 34 and the pipe 31, and the three-way valve 40 may be switched. Furthermore, although the case of two cylinders has been described, the present invention can also be applied to a case of multiple cylinders.

(Effects of the Invention) As explained above, according to the present invention, a passage is provided in the intermediate partition plate that partitions a plurality of cylinders, and this passage is closed during normal times and opened when the capacity is reduced, thereby reducing the load. It is possible to change the capacity according to the pressure, and in the case of a two-cylinder type, it is possible to control the capacity in two stages, and in the case of multiple cylinders, it is possible to control the capacity in other stages.In addition, because the passage from the high pressure chamber to the low pressure chamber is short, the release This has the effect of reducing time input.

[Brief explanation of drawings]

Fig. 1 is a longitudinal cross-sectional side view of the main parts of a multi-cylinder rotary compressor showing one embodiment of the present invention, Fig. 2 is a system diagram of the refrigeration cycle, and Fig. 3 is a diagram showing another embodiment of the invention. FIG. 4, a system diagram of a refrigeration cycle, is a partially cutaway side view of a general multi-cylinder rotary compressor. 5, 6...Cylinder, 21...Intermediate partition plate,
25...High pressure chamber, 26...Low pressure chamber, 27...Communication port (passage), 30...Opening/closing mechanism.

Claims (1)

[Claims] 1. In a multi-cylinder rotary compressor having a plurality of cylinders, the high pressure chamber side of one adjacent cylinder and the low pressure chamber side of the other cylinder are connected through a passage provided in an intermediate partition plate located between each cylinder. A multi-cylinder rotary compressor characterized by being provided with an opening/closing mechanism that communicates with each other and closes the passage during normal operation and opens the passage when the capacity is reduced.