CN104632624B - A two-cylinder two-stage compressor - Google Patents

Abstract

The invention discloses a kind of twin-tub double-stage compressor, including for refrigerant gas providing the low-pressure stage cylinder of one stage of compression and for the refrigerant gas after one stage of compression provides the hiigh pressure stage cylinder of two-stage compression, and the phase contrast of the air inlet start time of described low-pressure stage cylinder and described hiigh pressure stage cylinder is in the range of 120 ° 240 °.When low-pressure stage cylinder arrives aerofluxus peak, hiigh pressure stage cylinder just at inspiration peak position near, this is just so that the one stage of compression gas that low-pressure stage cylinder is discharged can be siphoned away by hiigh pressure stage cylinder in time, decrease intermediate cavity pressure fluctuation, ensure that low-pressure stage cylinder and the seriality of hiigh pressure stage cylinder suction and discharge and smoothness, the inspiration capacity simultaneously also making hiigh pressure stage cylinder is the most sufficient, is effectively increased the performance of compressor.

Description

A two-cylinder two-stage compressor

technical field

The invention relates to the technical field of preparation of air-conditioning compressors, in particular to a two-cylinder two-stage compressor.

Background technique

The current rolling rotor two-stage compressor generally includes a low-pressure stage cylinder and a high-pressure stage cylinder. The low-pressure stage cylinder forms a stage of compressed gas after completing the stage of compression. The compressed gas undergoes secondary compression to form a secondary compressed gas.

The suction connection between the low-pressure stage cylinder and the high-pressure stage cylinder in the current two-stage compression cylinder is not reasonable enough. It often happens that when the high-pressure stage cylinder is at the suction peak position, the low-pressure stage cylinder does not start to exhaust or does not reach the exhaust peak. The position is far away from the exhaust peak position, or when the suction rate of the high-pressure stage cylinder is low, the low-pressure stage cylinder is already at the exhaust peak position. These situations will lead to insufficient connection between the high-pressure stage and the exhaust gas. smooth, so that suction and exhaust pulsations are generated between the high-pressure stage cylinder and the low-pressure stage cylinder. The continuity of suction and exhaust between the low-pressure stage cylinder and the high-pressure stage cylinder will directly affect the performance of the compressor. When inhaled by the high-pressure stage cylinder, the first-stage compressed gas will accumulate in the intermediate chamber, causing the pressure in the intermediate chamber to rise. When the high-pressure stage cylinder is at the peak suction position, the low-pressure stage cylinder has not started to exhaust or is far from the exhaust peak position. If it is far away, this will lead to insufficient air intake of the high-pressure stage cylinder, resulting in a decrease in compressor performance.

Therefore, how to solve the problem of large suction and exhaust pulsation between the high-pressure stage cylinder and the low-pressure stage cylinder of the current double-cylinder two-stage compressor, so that the connection between the suction and exhaust process between the low-pressure stage cylinder and the high-pressure stage cylinder is smoother , is a technical problem urgently needed to be solved by those skilled in the art.

Contents of the invention

In view of this, the object of the present invention is to provide a double-cylinder two-stage compressor to solve the problem that the low-pressure stage and high-pressure stage of the current double-cylinder two-stage compressor have large suction and exhaust pulsations, so that the low-pressure stage cylinder and the high-pressure stage The suction and exhaust process between the cylinders is more smoothly connected, thereby improving the performance of the compressor.

To achieve the above object, the present invention provides the following technical solutions:

A two-cylinder two-stage compressor, comprising a low-pressure stage cylinder for providing primary compression of refrigerant gas and a high-pressure stage cylinder for providing secondary compression of refrigerant gas after primary compression, and the low-pressure stage The phase difference between the intake start moment of the stage cylinder and the high-pressure stage cylinder is in the range of 120°-240°.

Preferably, when the ratio of the discharge pressure to the suction pressure of the compressor is not greater than 2, the phase difference between the intake start time of the low-pressure stage cylinder and the high-pressure stage cylinder is in the range of 120°-180° Inside.

Preferably, the crankshaft eccentric portion of the low-pressure stage cylinder and the crankshaft eccentric portion of the high-pressure stage cylinder are arranged symmetrically at 180°, and the sliding vanes of the low-pressure stage cylinder and the sliding vanes of the high-pressure stage cylinder are in the direction of rotation of the crankshaft. The angle difference on is in the range of 0°-60°.

Preferably, the angle between the sliding vane of the low-pressure stage cylinder and the sliding vane of the high-pressure stage cylinder is 0°, and the crankshaft eccentric part of the low-pressure stage cylinder and the crankshaft eccentric part of the high-pressure stage cylinder are in the direction of crankshaft rotation. The angle difference above is in the range of 120°-180°.

Preferably, when the ratio of the discharge pressure to the suction pressure of the compressor is greater than 2, the phase difference between the intake start time of the low-pressure stage cylinder and the high-pressure stage cylinder is in the range of 180°-240° .

Preferably, the crankshaft eccentric portion of the low-pressure stage cylinder and the crankshaft eccentric portion of the high-pressure stage cylinder are arranged symmetrically at 180°, and the sliding vanes of the low-pressure stage cylinder and the sliding vanes of the high-pressure stage cylinder are in the direction of rotation of the crankshaft. The angle difference on is in the range of -60°-0°.

Preferably, the included angle between the sliding vanes of the low-pressure stage cylinder and the sliding vanes of the high-pressure stage cylinder is 0°, and the crankshaft eccentric part of the low-pressure stage cylinder and the high-pressure stage crankshaft eccentric part are in the crankshaft rotation direction The angle difference is in the range of 180°-240°.

It can be seen from the above-mentioned technical scheme that the phase difference of the intake start moment of the low-pressure stage cylinder and the high-pressure stage cylinder in the two-cylinder two-stage compressor provided by the present invention is in the range of 120°-240°, that is, the low-pressure stage When the cylinder reaches the position of the start of suction, the high-pressure stage cylinder will have to rotate 120°-240° to reach the position of the start of suction. With the rotation of the compressor crankshaft, when the low-pressure stage cylinder reaches the peak position of exhaust, The high-pressure stage cylinder is just near the suction peak position, which enables the primary compressed gas discharged from the low-pressure stage cylinder to be sucked away by the high-pressure stage cylinder in time, thereby avoiding the storage of the primary compressed gas in the intermediate cavity and causing suction and discharge. Large gas pulsation occurs, and the two-cylinder two-stage compressor also makes the air intake of the high-pressure stage cylinder relatively sufficient, thereby effectively improving the performance of the compressor.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

Fig. 1 is a partial cross-sectional schematic diagram of a two-cylinder two-stage compressor provided in an embodiment of the present invention;

Fig. 2 is a schematic top view of the low-pressure stage cylinder in the first embodiment;

Fig. 3 is a schematic top view of the high-pressure stage cylinder in the first embodiment;

Fig. 4 is a schematic plan view of the crankshaft eccentric part of the high-pressure stage cylinder and the crankshaft eccentric part of the low-pressure stage cylinder in the second embodiment;

Fig. 5 is a schematic top view of the low-pressure stage cylinder in the second embodiment;

Fig. 6 is a schematic top view of the high-pressure stage cylinder in the second embodiment;

Fig. 7 is a schematic top view of the high-pressure stage cylinder in the third embodiment;

Fig. 8 is a top view schematic diagram of the crankshaft eccentric part of the high-pressure stage cylinder and the crankshaft eccentric part of the low-pressure stage cylinder in the fourth embodiment;

Fig. 9 is a schematic top view of the low-pressure stage cylinder in the fourth embodiment;

Fig. 10 is a schematic top view of the high pressure stage cylinder in the fourth embodiment.

in,

1 is the crankshaft, 2 is the low-pressure cylinder, 3 is the high-pressure cylinder, and 4 is the middle cavity;

11 is the eccentric part of the crankshaft of the low-pressure cylinder, 12 is the eccentric part of the crankshaft of the high-pressure cylinder, 21 is the intake port of the low-pressure cylinder, 22 is the exhaust port of the low-pressure cylinder, 23 is the slide plate of the low-pressure cylinder, and 31 is the high-pressure cylinder Stage cylinder intake port, 32 is the exhaust port of the high-pressure stage cylinder, and 33 is the sliding vane of the high-pressure stage cylinder;

111 is a low-pressure roller, and 121 is a high-pressure roller.

detailed description

The core of the present invention is to provide a two-cylinder two-stage compressor to solve the problem that the gas in the low-pressure stage cylinder of the current two-cylinder two-stage compressor cannot be sucked away by the high-pressure stage cylinder in time, the gas volume is stored in the middle cavity, and the pressure in the middle cavity increases The technical problem of the pressure pulsation in the intermediate chamber caused by it makes the connection between the suction and exhaust process between the low-pressure stage cylinder and the high-pressure stage cylinder more smooth, thereby improving the performance of the compressor.

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

First, the core idea of the present invention is introduced: the two-cylinder two-stage compressor provided by the present invention includes a low-pressure stage cylinder for performing primary compression on the refrigerant gas and performing two-stage compression on the refrigerant gas after the primary compression. The high-pressure stage cylinder is designed by optimizing the intake start time of the low-pressure stage cylinder and the high-pressure stage cylinder, so that when the low-pressure stage cylinder is near the exhaust peak position, the high-pressure stage cylinder is just near the intake peak position, so that The refrigerant gas discharged from the low-pressure stage cylinder can be sucked away by the high-pressure stage cylinder in time, and the intake air volume of the high-pressure stage cylinder can be ensured to be sufficient.

Based on this design concept, the following is a detailed introduction to the two-cylinder two-stage compressor provided by the present invention through specific implementation methods. The two-cylinder two-stage compressor provided by the present invention includes a low-pressure compressor for providing one-stage compression of refrigerant gas. stage cylinder 2 and the high-pressure stage cylinder 3 that provides two-stage compression for the refrigerant gas after the first-stage compression, and the phase difference between the intake start time of the low-pressure stage cylinder 2 and the high-pressure stage cylinder 3 is in the range of 120°-240° Inside.

Here it is necessary to explain the concept of phase difference, assuming that the angle of the crankshaft at the moment when the low-pressure stage cylinder 2 starts to intake air is 0°, if the crankshaft continues to rotate A°, the high-pressure stage cylinder 3 starts to inhale, then we say the low-pressure stage The phase difference between cylinder 2 and high-pressure stage cylinder 3 is A°.

Those skilled in the art can easily understand that, since the phase difference of the intake start moment of the low-pressure stage cylinder 2 and the high-pressure stage cylinder 3 in the two-cylinder two-stage compressor provided by the present invention is within the range of 120°-240°, That is, when the low-pressure stage cylinder 2 reaches the position of the suction start moment, the high-pressure stage cylinder 3 has to rotate 120°-240° to reach the position of the suction start moment. With the rotation of the compressor crankshaft 1, the low-pressure stage cylinder 2 reaches the position of the suction start moment. When the exhaust peak position is near, the high-pressure stage cylinder 3 is just near the suction peak position, which enables the first-stage compressed gas discharged from the low-pressure stage cylinder 2 to be sucked away by the high-pressure stage cylinder 3 in time, thus avoiding the first stage Compressed gas is stored in the intermediate cavity 4, resulting in large intake and exhaust pulsations, and the double-cylinder two-stage compressor also makes the intake volume of the high-pressure cylinder 3 relatively sufficient, thereby effectively improving the performance of the compressor.

Depending on the operating environment of the compressor and the working conditions of the compressor, the phase difference between the start of air intake of the low-pressure stage cylinder 2 and the high-pressure stage cylinder 3 can be 120°, 180°, 240°, etc. within the range of 120°-240° Appropriate angle value.

In order to further optimize the technical solutions in the above embodiments, when the ratio of the discharge pressure to the suction pressure of the two-cylinder two-stage compressor provided in the present invention is not greater than 2 (i.e. low load), due to the low-pressure stage cylinder 2 exhaust The initial angle is small, so the phase difference between the intake start time of the low-pressure stage cylinder 2 and the high-pressure stage cylinder 3 is set in the range of 120°-180°, so as to ensure the suction between the low-pressure stage cylinder 2 and the high-pressure stage cylinder 3. The exhaust connection is smoother.

For the convenience of description, in the following embodiments, the phase difference between the intake start times of the low-pressure stage cylinder 2 and the high-pressure stage cylinder 3 is 120° or 180°.

Embodiment one

Please refer to Figures 1 to 3, Figure 1 is a partial cross-sectional view of a two-cylinder two-stage compressor provided in an embodiment of the present invention, Figure 2 is a top view of a low-pressure stage cylinder in the first embodiment, Figure 3 is a first A schematic top view of the high-pressure stage cylinder in the embodiment.

As shown in Figure 2, based on the crankshaft eccentric part 11 of the low-pressure stage cylinder, the crankshaft eccentric part 12 of the high-pressure stage cylinder and the crankshaft eccentric part 11 of the low-pressure stage cylinder are symmetrically arranged at an angle of 180°, please refer to Figure 3 at the same time, Both sides of the slide 23 of the low-pressure cylinder are respectively provided with a low-pressure cylinder inlet 21 and a low-pressure cylinder exhaust 22, and both sides of the slide 33 of the high-pressure cylinder are respectively provided with a high-pressure cylinder inlet 31 and a high-pressure cylinder. Cylinder exhaust port 32, because the angle between the crankshaft eccentric part 11 of the low-pressure stage cylinder and the crankshaft eccentric part 12 of the high-pressure stage cylinder is 180°, in order to ensure the phase of the intake start time of the low-pressure stage cylinder 2 and the high-pressure stage cylinder 3 The difference is 120°, and the angle difference between the slide plate 23 of the low-pressure stage cylinder and the slide plate 33 of the high-pressure stage cylinder in the direction of rotation of the crankshaft 1 is set to 60° (that is, relative to the slide plate 23 of the low-pressure stage cylinder, the high-pressure stage cylinder The sliding plate 33 rotates 60° counterclockwise), so that the phase difference between the start of air intake of the low-pressure stage cylinder 2 and the high-pressure stage cylinder 3 is 120°; The phase difference is 180°, and it is only necessary to set the angle between the slide plate 33 of the high-pressure stage cylinder and the slide plate 23 of the low-pressure stage cylinder to be 0°; The phase angle difference at the start moment is other values between 120°-180°, which can be determined by the angle between the crankshaft eccentric part 11 of the low-pressure stage cylinder and the crankshaft eccentric part 12 of the high-pressure stage cylinder and the sliding vane of the low-pressure stage cylinder 23 and the joint adjustment of the angle between the slide vanes 33 of the high-pressure stage cylinder to achieve.

Embodiment two

Please refer to FIG. 4 to FIG. 6, FIG. 4 is a schematic top view of the eccentric portion of the crankshaft of the high-pressure stage cylinder and the eccentric portion of the crankshaft of the low-pressure stage cylinder in the second embodiment, and FIG. 5 is a schematic top view of the low-pressure stage cylinder in the second embodiment. Fig. 6 is a schematic top view of the high-pressure stage cylinder in the second embodiment.

The two-cylinder two-stage compressor disclosed in Embodiment 1 ensures the air intake of the low-pressure stage cylinder 2 and the high-pressure stage cylinder 3 by jointly adjusting the included angle of the eccentric part of the crankshaft of the high-low pressure cylinder and the included angle of the slide vane of the high-low pressure cylinder. The phase difference at the beginning is within the ideal range. In the two-cylinder two-stage compressor disclosed in this embodiment, it is ensured by adjusting the angle between the crankshaft eccentric part 12 of the high-pressure stage cylinder and the crankshaft eccentric part 11 of the low-pressure stage cylinder. The phase difference between the intake start time of the low-pressure stage cylinder 2 and the high-pressure stage cylinder 3 is within an ideal range. Specifically, the included angle between the slide plate 23 of the low-pressure stage cylinder and the slide plate 33 of the high-pressure stage cylinder provided in this embodiment is 0° , so in order to construct the phase difference between the low-pressure stage cylinder 2 and the high-pressure stage cylinder 3 intake start time is 120°, then the angle between the crankshaft eccentric portion 11 of the low-pressure stage cylinder and the crankshaft eccentric portion 12 of the high-pressure stage cylinder in the direction of rotation of the crankshaft 1 The difference is 120°; in order to establish a phase difference of 180° between the low-pressure stage cylinder 2 and the high-pressure stage cylinder 3 when the air intake starts, the crankshaft eccentric part 11 of the low-pressure stage cylinder and the crankshaft eccentric part 12 of the high-pressure stage cylinder are in the rotation direction of the crankshaft 1 The angular difference on is 180°.

Of course, if it is necessary to construct a phase angle difference between the low-pressure stage cylinder 2 and the high-pressure stage cylinder 3 when the air intake starts to be other values between 120°-180°, the crankshaft eccentric portion 11 of the low-pressure stage cylinder and the high-pressure stage cylinder The angle adjustment between the crankshaft eccentric parts 12 is realized.

In the two-cylinder two-stage compressor provided in the embodiment of the present invention, when the ratio of the discharge pressure to the suction pressure is greater than 2 (that is, high load), the low-pressure stage cylinder 2 has a relatively large exhaust starting angle, so the low-pressure stage The phase difference between the intake start time of the cylinder 2 and the high-pressure cylinder 3 is set in the range of 180°-240°, so as to ensure a smoother connection of intake and exhaust between the low-pressure cylinder 2 and the high-pressure cylinder 3 .

For the convenience of description, in the following embodiments, the phase difference between the intake start times of the low-pressure stage cylinder 2 and the high-pressure stage cylinder 3 is 180° or 240°.

Embodiment Three

Please refer to Fig. 7. Fig. 7 is a schematic top view of the high-pressure cylinder in the third embodiment. It should be noted that the top view of the low-pressure cylinder in this embodiment is the same as that in Embodiment 1. Please refer to Figure 2 for the top view schematic diagram of the high-pressure cylinder, and please refer to Figure 7 for the top view schematic diagram of the high-pressure cylinder.

As shown in Fig. 2, based on the crankshaft eccentric part 11 of the low-pressure stage cylinder, the crankshaft eccentric part 12 of the high-pressure stage cylinder and the crankshaft eccentric part 11 of the low-pressure stage cylinder are symmetrically arranged at an angle of 180°. Please refer to Fig. 2 and Fig. 7, the two sides of the slide 23 of the low-pressure cylinder are respectively provided with a low-pressure cylinder inlet 21 and the low-pressure cylinder exhaust 22, and the two sides of the slide 33 of the high-pressure cylinder are respectively provided with a high-pressure cylinder inlet 31 and the exhaust port 32 of the high-pressure stage cylinder, because the included angle between the crankshaft eccentric portion 11 of the low-pressure stage cylinder and the crankshaft eccentric portion 12 of the high-pressure stage cylinder is 180°, in order to ensure that the intake air of the low-pressure stage cylinder 2 and the high-pressure stage cylinder 3 starts The phase difference at each moment is 180°, and the angle difference between the slide plate 23 of the low-pressure stage cylinder and the slide plate 33 of the high-pressure stage cylinder in the direction of rotation of the crankshaft 1 is set to 0°, so as to construct the low-pressure stage cylinder 2 and the high-pressure stage cylinder 3 The phase difference at the start of the air intake is 180°; if the phase difference between the intake start time of the low-pressure stage cylinder 2 and the high-pressure stage cylinder 3 is 240°, it is only necessary to set the slide plate 23 of the low-pressure stage cylinder to be the same as that of the high-pressure stage cylinder. The angle difference of the sliding vane 33 is -60° (that is, relative to the sliding vane 23 of the low-pressure cylinder, the sliding vane 33 of the high-pressure cylinder rotates 60° clockwise); of course, if it is necessary to construct the low-pressure cylinder 2 and the high-pressure The phase angle difference value of stage cylinder 3 air intake start moment is other values between 180°-240°, can pass the included angle between the crankshaft eccentric portion 11 of the low-pressure stage cylinder and the crankshaft eccentric portion 12 of the high-pressure stage cylinder and The common adjustment of the included angle between the slide plate 23 of the low-pressure stage cylinder and the slide plate 33 of the high-pressure stage cylinder is realized.

Embodiment four

Please refer to FIG. 8 to FIG. 10 , FIG. 8 is a schematic top view of the crankshaft eccentric portion of the high-pressure stage cylinder and the crankshaft eccentric portion of the low-pressure stage cylinder in the fourth embodiment, and FIG. 9 is a schematic top view of the low-pressure stage cylinder in the fourth embodiment. Fig. 10 is a schematic top view of the high pressure stage cylinder in the fourth embodiment.

The two-cylinder two-stage compressor disclosed in the third embodiment is to ensure that the low-pressure stage cylinder 2 and the high-pressure stage cylinder 3 are advanced by jointly adjusting the included angle of the eccentric part of the crankshaft of the high- and low-pressure stage cylinder and the included angle of the sliding vane of the high- and low-pressure stage cylinder. The phase difference at the start of gas is within the ideal range. In the two-cylinder two-stage compressor disclosed in this embodiment, the angle between the crankshaft eccentric part 11 of the high-pressure stage cylinder and the crankshaft eccentric part 12 of the low-pressure stage cylinder is adjusted. Ensure that the phase difference between the intake start time of the low-pressure stage cylinder 2 and the high-pressure stage cylinder 3 is within an ideal range. Specifically, the included angle between the slide plate 23 of the low-pressure stage cylinder and the slide plate 33 of the high-pressure stage cylinder provided in this embodiment is 0 °, so in order to construct the phase difference between the low-pressure stage cylinder 2 and the high-pressure stage cylinder 3 intake start time is 180°, then the crankshaft eccentric part 11 of the low-pressure stage cylinder and the crankshaft eccentric part 12 of the high-pressure stage cylinder in the direction of rotation of the crankshaft 1 The angle difference is 180°; in order to establish a phase difference of 240° at the start of air intake between the low-pressure stage cylinder 2 and the high-pressure stage cylinder 3, the crankshaft eccentric part 11 of the low-pressure stage cylinder and the crankshaft eccentric part 12 of the high-pressure stage cylinder rotate on the crankshaft 1 The angular difference in direction is 240°.

Of course, if it is necessary to construct other values between 180°-240° for the phase angle difference between the low-pressure stage cylinder 2 and the high-pressure stage cylinder 3 when the air intake starts, the crankshaft eccentric portion 11 of the low-pressure stage cylinder and the high-pressure stage cylinder The angle adjustment between the crankshaft eccentric parts 12 is realized.

Each embodiment in this specification is described in a progressive manner, each embodiment focuses on the difference from other embodiments, and the same and similar parts of each embodiment can be referred to each other.

The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention will not be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (5)

1. A two-cylinder two-stage compressor comprising a low-pressure stage cylinder (2) for providing one-stage compression of refrigerant gas and a high-pressure stage cylinder (3) for providing two-stage compression of refrigerant gas after the one-stage compression, characterized in that, when a ratio of discharge pressure to suction pressure of the compressor is not more than 2, a phase difference of intake start timings of the low-pressure stage cylinder (2) and the high-pressure stage cylinder (3) is in a range of 120 ° to 180 °; when the ratio of the discharge pressure to the suction pressure of the compressor is greater than 2, the phase difference between the intake start timings of the low-pressure stage cylinder (2) and the high-pressure stage cylinder (3) is in the range of 180-240 °.

2. The dual-cylinder dual-stage compressor as claimed in claim 1, wherein, when the ratio of the discharge pressure to the suction pressure of the compressor is not more than 2, the crank eccentric portion (11) of the low pressure stage cylinder and the crank eccentric portion (12) of the high pressure stage cylinder are symmetrically arranged by 180 °, and the difference in angle between the vane (23) of the low pressure stage cylinder and the vane (33) of the high pressure stage cylinder in the rotation direction of the crankshaft is in the range of 0 ° to 60 °.

3. The dual-cylinder dual-stage compressor as claimed in claim 1, wherein, when the ratio of the discharge pressure to the suction pressure of the compressor is not more than 2, the angle between the sliding vane (23) of the low pressure stage cylinder and the sliding vane (33) of the high pressure stage cylinder is 0 °, and the difference between the angle of the crankshaft eccentric portion (11) of the low pressure stage cylinder and the angle of the crankshaft eccentric portion (12) of the high pressure stage cylinder in the rotation direction of the crankshaft is in the range of 120 ° to 180 °.

4. The dual-cylinder dual-stage compressor as claimed in claim 1, wherein, when the ratio of the discharge pressure to the suction pressure of the compressor is greater than 2, the crank eccentric portion (11) of the low pressure stage cylinder and the crank eccentric portion (12) of the high pressure stage cylinder are symmetrically arranged by 180 °, and the difference in angle between the sliding vane (23) of the low pressure stage cylinder and the sliding vane (33) of the high pressure stage cylinder in the rotation direction of the crankshaft is in the range of-60 ° to 0 °.

5. The dual-cylinder dual-stage compressor as claimed in claim 1, wherein, when the ratio of the discharge pressure to the suction pressure of the compressor is greater than 2, the angle between the sliding vane (23) of the low pressure stage cylinder and the sliding vane (33) of the high pressure stage cylinder is 0 °, and the difference between the angle between the crankshaft eccentric portion (11) of the low pressure stage cylinder and the crankshaft eccentric portion (12) of the high pressure stage cylinder in the crankshaft rotation direction is in the range of 180 ° to 240 °.