JP2003227485A - Multi-cylinder compressors - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the efficiency by reducing suction loss by preventing the interference of pressure pulsation generated by one of the cylinders disturbing suction to an operating chamber of the other cylinder. <P>SOLUTION: A compressing mechanism part is provided with a plurality of cylinders 6a, 6b, each cylinder 6a, 6b is provided with a plurality of operating chambers 51, 52 defined by a partition plate 50 and a pair of end plates 5, 8. A crank shaft 3 is provided with a plurality of crank pins 13, 14 of different phases. A suction chamber 51 is provided with suction ports 20a, 20b communicated to suction pipes 19a, 19b through a suction channel. The suction channel has a channel part 30 communicating a channel part of each cylinder 6a, and channel parts 23a, 23b of the cylinder enlarged to both end faces of the cylinder. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-cylinder compressor, and particularly to a multi-cylinder compressor used in a refrigeration cycle such as a refrigerator or an air conditioner.

[0002]

2. Description of the Related Art As a conventional multi-cylinder compressor, as disclosed in Japanese Patent Laid-Open No. 8-270580, an electric motor section and a compression mechanism section are connected by a crankshaft and housed in a closed container. This compression mechanism section is provided with two cylinders and each cylinder has two working chambers defined by a partition plate and a pair of end plates, and the crankshaft has a plurality of eccentric crankpins with different phases. Arranged so as to eccentrically rotate each working chamber by fitting a piston to each of the crank pins, the working chamber has a suction port communicating with a suction pipe connected to the cylinder via a suction flow path, There is one in which the suction flow passage is formed to have a flow passage portion that communicates between the flow passage portions of the cylinders.

In this prior art, there is shown a specific example in which a suction pipe is connected to a specific cylinder and a passage portion is formed which communicates from the inside of this suction pipe to the suction port of another cylinder. ing.

Further, in this prior art, a suction pipe is connected to each of the two cylinders, and a flow passage portion for communicating the flow passage portions of the two cylinders is provided inside the portion where the suction pipe is connected. The example formed is also shown.

[0005]

In the above-mentioned prior art, when the compressor is operated, the suction flow rate changes due to the volume change of each working chamber, and pressure pulsation occurs in the suction flow passage. As a result, the pressure pulsation generated by one working chamber may cause interference that hinders the suction action to the other working chamber. However, the prior art does not give sufficient consideration to this point.

Further, according to the prior art, in a flow passage portion which communicates between the flow passage portions of each cylinder, a flow resistance in the suction port direction of a specific cylinder and a flow resistance in the suction port direction of another cylinder are No relationship was disclosed. Here, when the flow resistance in the suction port direction of the specific cylinder is smaller than the flow resistance in the suction port direction of the other cylinder, the other in the suction stroke of the working chamber of the specific cylinder There is a problem that the gas once sucked into the working chamber of the cylinder may flow back to the working chamber of a specific cylinder.

A first object of the present invention is to prevent the pressure pulsation generated by one cylinder from interfering with the suction of the other cylinder into the working chamber and reduce the suction loss.
It is to provide a multi-cylinder compressor that can improve efficiency.

A second object of the present invention is to provide a multi-cylinder compressor which can prevent backflow of suction gas in the other working chamber due to suction stroke of one working chamber to reduce suction loss and improve efficiency. Especially.

The objects and advantages of the present invention other than the above will be apparent from the following description.

[0010]

In order to achieve the first object, in a multi-cylinder compressor of the present invention, an electric motor part and a compression mechanism part are connected and housed in a closed container by a crankshaft, The compression mechanism unit includes a plurality of cylinders and a plurality of working chambers defined by partition plates and end plates in each of the cylinders, and the crankshaft includes a plurality of eccentric crankpins with different phases. A multi-cylinder compressor having pistons fitted to the crank pins so as to eccentrically rotate in the working chambers, and the working chambers have suction ports communicating with suction pipes connected to the cylinders through suction passages. In the above, the suction flow passage has a flow passage portion that communicates between the flow passage portions of the cylinders, and a cylinder flow passage portion that extends to both end surfaces of the cylinder. Lies in the thing.

In order to achieve the second object, a multi-cylinder compressor of the present invention has a hermetically sealed container in which an electric motor section and a compression mechanism section are connected by a crankshaft and housed, and the plurality of compression mechanism sections are provided. And a plurality of working chambers partitioned by partition plates and end plates are formed in each of the cylinders, and the crankshaft is provided with a plurality of eccentric crankpins with different phases and a piston at each of the crankpins. Is arranged so as to eccentrically rotate in each of the working chambers, and the working chambers have a suction port communicating with a suction pipe connected to the cylinder via a suction flow path, wherein the cylinders are: The suction pipe has a specific cylinder to which the suction pipe is connected, and another cylinder to which the suction pipe is not connected, and the suction flow path includes the suction pipes. Has a channel portion communicating between the mouth,
This communication flow path portion is configured to have a fluid diode portion in which the flow resistance in the suction port direction of the specific cylinder is larger than the flow resistance in the suction port direction of the other cylinder.

Other means of the present invention will be apparent from the following description.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. In addition, in the second embodiment, a part of the configuration common to the first embodiment is omitted, and the duplicate description is omitted. The same reference numerals in the drawings of the respective embodiments indicate the same or equivalent components.

A multi-cylinder compressor according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 3. 1 is a longitudinal sectional view showing a multi-cylinder rotary compressor according to a first embodiment of the present invention, FIG. 2 is an enlarged view of a main part of FIG. 1, and FIG.
FIG.

1 to 3, 1 is a closed container,
Reference numeral 2 is an electric motor portion, 2a is a rotor of the electric motor, 2b is a stator, 3 is a crankshaft, 4 is a main bearing, 5 is a compression mechanism portion, 6
a is a first cylinder, 6b is a second cylinder, 50 is a partition plate, 8 is a sub-bearing, 9 is a cover, 10a is a first piston, 10b is a second piston, 11 is a cover, 12
a, 12b are vanes, 13 is the first crank pin, 14
Is a second crank pin, 15 is a discharge chamber, 16 is a discharge gas passage, 17 is a discharge chamber, 18 is a discharge pipe, 19a, 19
Reference numeral b is a suction pipe, 20a and 20b are suction ports of the cylinder, 21a and 21b are suction flow passage portions reaching the suction ports 20a and 20b, and 22a and 22b are suction pipes 19a1.
9b is a suction flow passage portion, 23a is a flow passage portion connecting the suction flow passage portions 21a and 22a, 23b is a suction flow passage portion connecting the suction flow passage portions 21b and 22b, 3
Reference numeral 0 is a suction flow passage portion that connects the suction flow passage portions 23a and 23b.

This first embodiment is intended for a two-cylinder rotary compressor having two cylinders.

A main bearing 4 for supporting the crankshaft 3 is fixed to the inner wall of the closed container 1 by welding or the like. The electric motor unit 2 is housed in one space of the main bearing 4, and the compression mechanism unit 5 is housed in the other space. The electric motor unit 2 is composed of a rotor 2a fitted with a crankshaft 3 and a stator 2b which is opposed to and coaxial with the rotor 2a, and the stator 2b is fixed to the closed casing 1.

In the compression mechanism portion 5, the crankshaft 3 further extends from the main bearing 4, and the tip end portion thereof is supported by the auxiliary bearing 8. Between the main bearing 4 and the sub bearing 8, two cylinders 6a and 6b and a partition plate 50 are partitioned to form two sets of working spaces. Crank pin portions 13 and 14 formed on the crank shaft 3 are arranged in the cylinders 6a and 6b, respectively. In addition, in the cylinders 6a and 6b, the piston 10
a and 10b are stored respectively. The pistons 10a and 10b are fitted in the crank pin portions 13 and 14, respectively. The crankpins 13 and 14 are formed with a phase difference of 180 ° in the circumferential direction of the crankshaft 3.

When the crankshaft 3 is rotationally driven by the electric motor portion 2, the pistons 10a and 10b rotate with a phase difference of 180 ° with each other as the crankpin portions 13 and 14 rotate. The vanes 12a and 12b are constantly pressed against the pistons 10a and 10b by a spring member. Although the vane 12b is not shown, the description is given with the reference numeral 12b for easy understanding. In the cylinder 6a, a working chamber including a suction chamber 51 and a compression chamber 52 is formed by the piston 10a and the vane 12a.
Further, in the cylinder 6b, the piston 10b and the vane 12b are
With the above, a working chamber including the suction chamber 51 and the compression chamber 52 is formed. The suction chamber 51 on the cylinder 6b side
Is not shown, the reference numeral 6 is provided for easy understanding.
The description will be given with b.

The piston 10 by the rotation of the crankshaft 3
Due to the eccentric rotation of a and 10b, the suction chamber 51 and the compression chamber 52 in the cylinders 6a and 6b repeatedly contract and expand. When the suction chambers 51 of the cylinders 6a and 6b are expanded, the refrigerant gas is supplied from the refrigeration cycle through the suction pipes 19a and 19b, and is further sucked into the respective suction chambers 51 through the suction passage.

As the compression chamber 52 shrinks as the crankshaft 3 rotates, the refrigerant gas is compressed and when these pressures reach a certain level (discharge pressure), the compressed refrigerant gas in the cylinder 6a and the main bearing 4 and its While being discharged to the discharge chamber 17 formed by the cover 11, the compressed refrigerant gas in the cylinder 6b is discharged to the discharge chamber 15 formed by the auxiliary bearing 8 and its cover 9. The refrigerant gas is alternately compressed by the cylinders 6a and 6b, and is discharged into the discharge chambers 17 and 15
Is discharged into the closed container 1 through the discharge pipe 18, and further discharged from the closed container 1 to the refrigeration cycle through the discharge pipe 18.

The suction pipes 19a and 19b are the cylinder 6
a, 6b connected to the portion extending in the direction of the closed container 1,
It communicates with the suction ports 20a, 20b formed in the suction chamber 51 via the suction flow passages formed in the cylinders 6a, 6b. The suction flow passages include suction flow passage portions 22a, 23a, 21a formed in the cylinder 6a and suction flow passage portions 22b, 23b, 2 formed in the cylinder 6b.
1b and the suction flow path portion 30 formed in the partition plate 50
It consists of and.

The suction passage portions 23a, 30 and 23b are provided so as to penetrate through the cylinders 6a and 6b and the flange portion of the partition plate 50, and are constituted by holes having a circular cross-sectional area. The suction flow passage portions 23a, 30 and 23b are configured to communicate with each other in parallel to the crankshaft center (vertical direction in the drawing), and both ends thereof are closed by the flange surfaces of the main bearing 5 and the sub bearing 8.

The suction flow passage portions 22a and 22b include the suction pipes 19a and 19b and the suction flow passage portions 23a and 23b.
And extend in the radial direction so as to communicate with. The suction flow path portions 21a and 21b are the suction flow path portions 23a and 23b.
And the suction ports 20a and 20b communicate with each other in the radial direction. Therefore, the suction ports 20a, 20b are connected to the suction flow path portions 21a, 23a, 30, 23b, 21b.
Are communicated with each other via. Also, the suction port 20a
Is a suction flow path portion 21a, 23a, 30, 23b, 22
It communicates with the suction pipe 19b through b. The suction port 20b is connected to the suction flow path portions 21b, 23b,
It is connected to the suction pipe 19a via 30, 23a, 22a.

According to this embodiment, when the volume change of the suction chamber 51 of the first cylinder 6a is large and the suction flow rate is large, the refrigerant gas mainly flows from the first suction pipe 19a to the suction flow passage portions 22a23a, 21a. Although it is sucked into the first suction port 20a through it, the suction flow path portions 22b, 23b, 30, 23a, 2 are also sucked from the second suction pipe 19b.
It is sucked into the first suction port 20a through 1a. At this time, the volume change of the suction chamber 51 of the second cylinder 6b is small because the phase is shifted by 180 °, and the suction flow rate is small.

On the contrary, the suction chamber 5 of the second cylinder 6b
When the volume change of 1 is large and the suction flow rate is large, the refrigerant gas mainly flows from the second suction pipe 19b to the suction flow path portion 2
The second suction port 20b is sucked into the second suction port 20b through 2b, 23b, 21b, but also through the suction flow path portions 22a, 23a, 30, 23b, 21b from the first suction pipe 19a. Is sucked into. At this time, the volume change of the suction chamber of the first cylinder 6a is small because the phase is shifted by 180 °, and the suction flow rate is small.

The two-cylinder rotary compressor has a large change in volume during one rotation and a large change in suction flow rate, but the maximum suction flow rate of each cylinder 6a, 6b is 18
The phases appear 0 ° out of phase, and in the present embodiment, as described above, since the suction flow passages of the cylinders 6a and 6b communicate with each other through the suction flow passage portion 30, one suction port 20a is connected. Or both suction pipes 1 to 20b
The refrigerant gas can be sucked from 9a and 19b, and the loss due to the flow path resistance in the suction pipes 19a and 19b can be reduced.

However, each cylinder 6a, 6b
Since pressure pulsation occurs in the suction flow passages of the respective cylinders 6a and 6b due to the volume change of the suction chamber 51, if the respective suction flow passages are simply made to communicate with each other, they are affected by the pressure pulsation of each other and the suction state becomes unstable. Or the suction flow rate may decrease. In the present embodiment, the suction passage portions 23a of the cylinders 6a and 6b,
An extremely large flow path portion is formed in contact with the main bearing 4 and the sub bearing 8 which are end plates enlarged to open both ends of the cylinder 23b. The flow path portions 23a and 23b are the cylinder 6
a, 6b has a length in the axial direction, and the axial direction of the cylinders 6a, 6b of the flow passage portions 23a, 23b is larger than the cross-sectional area of the suction flow passage portions 21a, 21b, 22a, 22b in the gas flow direction. The structure has a larger cross-sectional area. Therefore, the gas flow velocity flowing from the suction pipes 19a and 19b is reduced in the suction flow passage portions 23a and 23b,
This has the effect of reducing the pressure pulsation that occurs. in addition,
Since the respective suction flow passage portions 23a and 23b are communicated with each other by the suction flow passage portion 30, there is an effect that the flow rates flowing into the suction flow passage portions 23a and 23b are averaged and the generated pressure pulsation is significantly reduced. .

Therefore, according to this embodiment, the pressure pulsation generated in the suction passages of the respective cylinders 6a and 6b can be reduced, interference between the suctions of the cylinders 6a and 6b can be prevented, and the suction flow rate loss can be prevented. And the efficiency of the compressor can be improved.

Next, a second embodiment of the present invention will be described with reference to FIGS.
Will be described with reference to. FIG. 4 is a sectional view of a main part of a multi-cylinder compressor according to a second embodiment of the present invention, and FIG. 5 is a sectional view taken along line BB of FIG. The second embodiment is different from the first embodiment as described below, and is basically the same as the first embodiment in other points.

4 and 5, the suction passage portion 23a having a circular cross-sectional area is provided in the first cylinder 6a and communicates with the suction pipe 19a through the suction passage portion 22a. The suction flow path portion 30 is formed by the partition plate 5.
0, and is composed of a tapered portion 30a and an edge portion 30b. The tapered portion 30a is the first cylinder 6a.
From the side toward the second cylinder 6b side. The edge portion 30b is formed to have a small diameter that matches the narrow diameter of the tapered portion 30a, and is opened to the side of the second cylinder 6a. The suction flow passage portion 23b having a circular cross section is formed from the end surface of the second cylinder 6b and extends partway without reaching the end surface on the other side. Further, the suction flow path portion 2 having a circular cross-sectional area
3b is provided in the second cylinder 6a and communicates with the suction flow passage portion 30 through the upper surface opening. Suction port 20
The a and 20b are opened in the suction chamber 51 of each cylinder 6a and 6b by a groove having a narrow width. Suction channel portions 21a, 2
1b is a suction port 20a, 20b and a suction flow path portion 23
a, 23b, and a suction flow path portion 23
It is connected so as to inscribe the circles a and 23b. In the second embodiment, the suction pipe is not connected to the cylinder 6b.

In the second embodiment, the refrigerant gas is sucked due to the volume change of the respective cylinders 6a and 6b, but when the suction flow rate of the first cylinder 6a is large, the refrigerant gas is sucked from the suction pipe 19a. Road part 23
After flowing into a, the cross-sectional area of the flow passage is enlarged, and the flow velocity is reduced there, and then is sucked into the suction chamber 51 of the first cylinder 6a through the suction flow passage portion 21a and the suction port 20a. At this time, due to the pressure change generated in the suction flow path portion 23a,
The gas also tries to flow backward from the suction flow passage portion 23b side, but the flow rate can be reduced by the fluid diode action of the suction flow passage portions 21b and 23b and the suction flow passage portion 30. That is, when a backflow that is sucked out from the second cylinder 6b occurs, the refrigerant gas flows tangentially from the suction flow passage portion 21b provided so as to be inscribed in the suction flow passage portion 23b into the suction flow passage portion 23b. However, a vortex flow is generated therein, and the backflow from the suction flow passage portion 30 narrowed by the edge portion 30b is reduced.

On the other hand, when the suction flow rate of the second cylinder 6b is large, the refrigerant gas flows from the suction pipe 19a into the suction passage portion 23a, and the suction passage portions 30, 23b,
21b and the suction port 20b, and the second cylinder 6
It is sucked into the suction chamber 51 of b. At this time, the suction flow passage portion 23a reduces the flow velocity, reduces the pressure pulsation, and reduces the flow passage resistance due to bending. Further, the flow passage resistance in the suction direction hardly increases due to the tapered portion 30a. Furthermore, since the flow flows from the suction flow path portion 23b to the suction flow path portion 21b along the inner wall, the flow path resistance here hardly increases. When the suction flow rate of the second cylinder 6b is high, a backflow is generated so as to be sucked out from the suction chamber 51 of the first cylinder 6a. However, due to the inertial force of the gas flowing from the suction pipe 19a, the suction flow passage portion 21a is discharged. It pushes the outflow and reduces backflow.

Further, as in the second embodiment, the suction ports 20a, 20b opening in the cylinders 6a, 6b are constituted by a groove having a width smaller than the inner diameter of the suction passage and the suction pipe 19a. ,effective.
In the rotary compressor, since the suction ports 20a, 20b open to the suction chamber 51 of the cylinders 6a, 6b at the start of compression during one rotation, the suction ports 20a, 20b
The start of compression is delayed until b is closed by the pistons 10a and 10b, and the compressed gas left in the discharge hole 24 re-expands and flows backward from the suction ports 20a and 20b. Therefore, when the suction ports 20a and 20b are large,
The start of compression is delayed and the reverse flow rate increases. Therefore, in the second embodiment, since the suction ports 20a and 20b having a narrow width are used, there is an effect of accelerating the start of compression and reducing the reverse flow rate. Furthermore, since it is made to flow into the suction flow passage portion 21b along the inner wall of the circular cross section of the suction flow passage portion 23b,
The resistance in the suction flow passage 21b is also reduced, and the suction flow rate loss can be reduced.

[0035]

As is apparent from the above description, according to the present invention, it is possible to prevent the pressure pulsation generated by one cylinder from interfering with the suction of the other cylinder into the working chamber and reduce the suction loss. A multi-cylinder compressor that can improve efficiency is obtained.

Further, according to the present invention, it is possible to obtain the multi-cylinder compressor which can prevent the backflow of the suction gas in the other working chamber due to the suction stroke of the one working chamber to reduce the suction loss and improve the efficiency.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a multi-cylinder rotary compressor according to a first embodiment of the present invention.

FIG. 2 is an enlarged view of a main part of FIG.

3 is a cross-sectional view taken along the line AA of FIG.

FIG. 4 is a lateral cross-sectional view of a main part of a multi-cylinder compressor according to a second embodiment of the present invention.

5 is a sectional view taken along line BB of FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Airtight container, 2 ... Electric motor part, 2a ... Rotor, 2b ... Stator, 3 ... Crank shaft, 4 ... Main bearing, 5 ... Compression mechanism part, 6a, 6b ... Cylinder, 8 ... Sub bearing, 9 ... Cover,
10a, 10b ... Piston, 11 ... Cover, 12a, 1
2b ... Vane, 13 ... First crank pin, 14 ... Second
Crank pin, 15 ... discharge chamber, 16 ... discharge gas passage,
Reference numeral 17 ... Discharge chamber, ... Discharge pipe, 19a, 19b ... Suction pipe, 20a, 20b ... Suction port, 21a, 21b,
22a, 22b, 23a, 23b ... Suction flow path part, 24
... Discharge hole, 30 ... Suction flow path part, 30a ... Tapered part,
30b ... Edge portion, 50 ... Partition plate, 51 ... Suction chamber,
52 ... compression chamber.

Claims (6)

[Claims] 1. An electric motor unit and a compression mechanism unit are connected and housed in a closed container by a crankshaft, and the compression mechanism unit includes a plurality of cylinders, and each cylinder is partitioned by a partition plate and an end plate. A plurality of working chambers are formed, the crankshaft is provided with a plurality of eccentric crankpins with different phases, and pistons fitted to the crankpins are arranged so as to eccentrically rotate in the working chambers. A multi-cylinder compressor in which the working chamber has a suction port that communicates with a suction pipe connected to the cylinder via a suction flow path, wherein the suction flow path is a flow path that communicates between the flow path portions of the cylinders. A multi-cylinder compressor having a passage portion and a cylinder passage portion that extends to both end surfaces of the cylinder. 2. A multi-cylinder compressor according to claim 1, wherein a suction pipe is connected to all of said cylinders, and each of said cylinders has a cylinder flow path portion which extends to both end surfaces of the cylinder. 3. The multi-cylinder compressor according to claim 1, wherein the volume of the suction space is larger than the maximum volume of one of the working chambers. 4. An electric motor section and a compression mechanism section are connected and housed in a closed container by a crankshaft, and the compression mechanism section is provided with a plurality of cylinders, and each cylinder is divided by a partition plate and an end plate. A plurality of working chambers are formed, the crankshaft is provided with a plurality of eccentric crankpins with different phases, and a piston is fitted to each of the crankpins so as to eccentrically rotate in each of the working chambers; In a multi-cylinder compressor in which the chamber has a suction port communicating with a suction pipe connected to the cylinder via a suction flow passage, the suction flow passage has a flow passage portion communicating between the flow passage portions of each cylinder. A flow path portion having a circular cross-sectional area extending in the axial direction and a flow path portion communicating from the suction port so as to be inscribed in the flow path portion extending in the axial direction. A characteristic multi-cylinder compressor. 5. An electric motor section and a compression mechanism section are connected and housed in a closed container by a crankshaft, and the compression mechanism section is provided with a plurality of cylinders, and each cylinder is divided by a partition plate and an end plate. A plurality of working chambers are formed, the crankshaft is provided with a plurality of eccentric crankpins with different phases, and a piston is fitted to each of the crankpins so as to eccentrically rotate in each of the working chambers; In a multi-cylinder compressor having a suction port in which a chamber communicates with a suction pipe connected to the cylinder via a suction flow path, the cylinder does not connect the suction pipe to a specific cylinder to which the suction pipe is connected. And a cylinder, and the suction flow passage has a flow passage portion that communicates between the flow passage portions of the cylinders. Multiple cylinder compressors, characterized in that it comprises a fluid diode portion towards the flow resistance increases in the inlet direction of the specific cylinder from the flow resistance in the inlet direction of the other cylinder. 6. The multi-cylinder compressor according to claim 5, wherein the fluid diode section is formed on the partition plate.