JPH04255589A - Scroll type compressor - Google Patents

Abstract

PURPOSE:To prevent overcompression and to suppress an input loss by contriving pressure balance, decreasing compression ratio, and substantially reducing stress in a blade part at the time of high suction pressure operation. CONSTITUTION:An essential suction amount of compressed gas in the first compression chamber A, which compresses compressed gas sucked from a suction port 11 provided in a volute finish end part S in a blade part 9 of a fixed scroll blade 3, is larger than the second compression chamber B for compressing compressed gas sucked from a suction port 12 provided in a position opposed 180 deg. from the above-mentioned volute finish end part. However, a total sectional area of a release port, provided in the first compression chamber, is formed larger than the total sectional area of a release port provided in the second compression chamber, so that various effects can be guided by balancing pressure mutually of each compression chamber.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll compressor used, for example, as a compressor constituting a refrigeration cycle of an air conditioner.

0002

[Prior Art] For example, a compressor that makes up the refrigeration cycle of an air conditioner that can switch between cooling operation and heating operation has extremely low kinetic noise and compression compared to a normal rotary compressor. Scroll compressors with good performance tend to be used frequently.

This type of scroll compressor has better volumetric efficiency than a normal rotary compressor, and the compression ratio does not fluctuate and always remains constant, so the suction pressure is high, especially during heating operation. Problems are likely to occur in some cases.

That is, in this compressor, fixed scroll blades and orbiting scroll blades having spiral blade portions of the same shape are meshed with each other, and the orbiting scroll blades are caused to rotate, thereby sucking and compressing refrigerant gas. It is designed to form a chamber.

To explain, by meshing the blade portions of the fixed scroll blade and the orbiting scroll blade with each other,
a first compression chamber for compressing the compressed gas sucked from a suction port provided near the winding end of the wing section of the fixed scroll blade; and a position 180° opposite from the winding end of the fixed scroll blade. The symmetrical two compression chambers compress the compressed gas sucked in from the suction port provided in the second compression chamber.
Two compression chambers are formed.

[0006]

[Problems to be Solved by the Invention] As mentioned above, when the suction pressure rises to a high state, the pressure in the center of the wing becomes extremely high, which not only increases the input loss, but also increases the suction pressure. Wing stress increases and in extreme cases leads to failure.

As shown in FIG. 11, the first and second compression chambers have different compression capacity contribution rates. That is, the first compression chamber that sucks and compresses the compressed gas from the suction port formed at the winding end of the blade part of the fixed scroll blade is as follows:
It is possible to suck in and compress a larger amount of refrigerant gas than in the second compression chamber, which sucks in and compresses the gas to be compressed from the suction port provided at a position 180° opposite from the winding end.

Therefore, even though the compression capacity contribution ratios of the first and second compression chambers are different from each other at a ratio of approximately 3:2, when high suction pressure is applied, the first compression chamber , an unbalanced force is generated in the second compression chamber, resulting in a decrease in compression efficiency.

The present invention has been made in view of the above-mentioned circumstances, and its purpose is to reduce the compression ratio by balancing the pressures among the compression chambers, so that even during high suction pressure operation, the blades The present invention aims to provide a scroll compressor that can significantly reduce stress in the compressor, prevent overcompression, and suppress input loss.

0010

[Means for Solving the Problems] In order to satisfy the above object, the present invention provides a fixed scroll wing and an orbiting scroll wing having spiral wing portions of the same shape, which are meshed with each other. A first compression chamber that compresses the compressed gas sucked from a suction port provided near the end of the winding of the fixed scroll blade, and a suction port provided at a position 180° opposite from the end of the winding of the fixed scroll blade. In a scroll compressor that forms two symmetrical compression chambers with a second compression chamber that compresses compressed gas to be sucked in, a release port is provided in each of the first compression chamber and the second compression chamber. , a scroll compressor characterized in that the total cross-sectional area of the release ports provided in the first compression chamber is larger than the total cross-sectional area of the release ports provided in the second compression chamber.

[0011]

[Operation] The first compression chamber that compresses the compressed gas sucked in from the suction port provided at the winding end of the wing section of the fixed scroll blade is 180 degrees opposite from the winding end of the fixed scroll blade. Originally, the suction amount of the compressed gas is larger than that of the second compression chamber which compresses the compressed gas sucked from the suction port provided at the position.

On the other hand, since the total cross-sectional area of the release ports provided in the first compression chamber is made larger than the total cross-sectional area of the release ports provided in the second compression chamber, The pressure in the second compression chamber is balanced,
In addition to eliminating the unbalance caused by gas pressure, the compression ratio is lowered and blade stress is significantly reduced even during high suction pressure operation, preventing overcompression and suppressing input loss.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, 1 is a sealed case;
A support frame 2 is installed inside the sealed case 1.
The interior is divided into upper and lower parts.

At the upper part of the support frame 2, a valve cover 6 surrounds the fixed scroll blades 3, the orbiting scroll blades 4, and the discharge side space on the side of the fixed scroll blades 3, and forms a high pressure discharge chamber 5 inside. A scroll compression mechanism section K is provided.

Both the fixed scroll blade 3 and the orbiting scroll blade 4 have end plate portions 7, 8, and end plate portions 7, 8.
It is composed of spiral wing portions 9 and 10 that are integrally provided with. These wing portions 9 and 10 are engaged with each other, and a space surrounded by the mirror plate portions 7 and 8 is formed.

As shown in FIG. 2, the space section is 180
° A pair of compression chambers A and B are provided for the suction ports 11 and 12 that are provided opposite to each other. That is, the first compressor sucks and compresses the gas to be compressed from the suction port 11 provided near the winding end S of the wing portion 9 of the fixed scroll blade 3.
A second compression chamber B is formed, which sucks and compresses the gas to be compressed from the suction port 12 provided at a position 180 degrees opposite from the suction port 11.

The first and second compression chambers A and B have symmetrical shapes, and as the orbiting scroll blades 4 rotate, their positions gradually move in the rotation direction and their areas decrease. Eventually, it moves to the discharge port 13 provided on the spiral start end side of each wing section 9, 10, and the area becomes approximately zero.

As shown in the figure, release ports 14 are provided in the first compression chamber A and the second compression chamber B, respectively. The first compression chamber A is provided with two release ports 14, 14, and the second compression chamber B is provided with:
1. A release port 14 is provided.

All release ports 14 have the same opening area. Therefore, from the total cross-sectional area of the release port 14 provided in the second compression chamber B, the first
The total cross-sectional area of the release port 14 provided in the compression chamber A becomes large.

As shown again in FIG. 1, the release ports 14 are provided through the end plate 7 of the fixed scroll blade 3 and communicate with the release chamber 15 provided in the end plate 7.

The upper end opening of the release chamber 15 is closed by a partition plate 16 interposed between the end plate 7 and the flange of the valve cover 6. The cross-sectional shape of the mirror plate portion 7 is as shown in FIG.

In the figure, 17 is a high pressure chamber communicating with the high pressure discharge chamber 5 inside the valve cover 6, and 18 is a discharge gas passage. A release tube 19 communicates with the release chamber 15 . The partition plate 16 is designed as shown in FIG. In the figure, 20 is a high pressure gas communication port.

On the other hand, each of the release ports 14
... are opened and closed by a valve mechanism 21 provided in the release chamber 15, as shown in FIG. That is, a valve seat 22 is provided along the open end of each release port 14, and a check valve 23 for opening and closing the open end of the release port 14 is provided there.

Further, a valve stopper 24 is provided with a predetermined gap between the check valve 23 and the valve stopper 24 to prevent the check valve 23 from opening when high pressure is applied to the release chamber 15. ing.

As described above, the valve mechanism 21 is of the so-called free valve type, but it may also be of the so-called reed valve type, in which, for example, a check valve and a valve stopper are stacked one on top of the other, and one end thereof is attached and fixed to the valve seat. It may be something. Further, when the fixed scroll blade 3 is made of, for example, an aluminum material, only the valve seat 22, for example, S
It is also conceivable to use different types of wear-resistant materials such as CM.

As shown again in FIG. 1, a discharge pipe 25 is connected to the discharge gas passage 18 provided in the end plate 7 of the fixed scroll blade 3, and this discharge pipe 25 extends outside from the sealed case 1. Communicated with the condenser. Further, a suction pipe 26 is connected to a substantially central portion of the sealed case 1, and communicates with an evaporator (not shown).

As shown in FIG. 6, a release pipe 28 connected to one connection port of a three-way valve 27 is connected to the suction pipe 26 on the suction side of the compressor C. The release pipe 19 is connected to the other connection port of the three-way valve 27, and the release bypass pipe 29, which communicates with the midway portion of the discharge pipe 25, is connected to the remaining connection port of the three-way valve 27.

That is, when the three-way valve 27 is switched so that the release pipe 19 and the release pipe 28 communicate with each other, a portion of the refrigerant gas compressed in the first and second compression chambers A and B is transferred to each release port. 14 through the release chamber 15 and released to the suction pipe 26 side.

When the three-way valve 27 is switched so that the release pipe 19 and the release bypass pipe 29 communicate with each other, a portion of the high pressure gas discharged from the discharge pipe 25 flows into the release chamber 15.
is guided to each release port 1 via the valve mechanism 21.
4. It is designed to close...

As shown again in FIG. 1, an electric motor section D consisting of a stator 30 and a rotor 31 is provided at the lower part of the support frame 2. This electric motor section D and the scroll compression mechanism section K are connected via a main shaft 32.

Note that the stator 30 is mounted on the support frame 2.
A fixing bolt 33 is attached and fixed to the stator 30 as well as a stay 34, and an oil pump 35 provided at the lower end of the main shaft 32 is supported at a substantially central portion of the stay 34. The oil pump 35 is provided with a rotor cover 36.

To explain further, as shown enlarged in FIG. 7, the pump case 37 constituting the oil pump 35
The rotor cover 36 is attached to the upper surface via a rotor cover holder 38. The rotor cover 36 has a substantially U-shaped cross section, and its peripheral end is interposed between the rotor end ring 31a and the stator coil end 30a.

[0033] In the scroll compressor constructed in this manner, the motor section D is energized to drive the scroll compression mechanism section K, and low-pressure refrigerant gas, which is the gas to be compressed, is introduced from the suction pipe 26. to fill the airtight case 1.

[0034] This refrigerant gas is transferred to the scroll compression mechanism section K.
In the first compression chamber A and the second compression chamber B formed between the fixed scroll blade 3 and the orbiting scroll blade 4 that constitute the
They are sucked in through suction ports 11 and 12, respectively.

The refrigerant gas sucked into the first and second compression chambers A and B is compressed as the orbiting scroll blades 4 rotate. Once the pressure has risen to a predetermined level, it is discharged into the high-pressure discharge chamber 5 and further led to an external condenser via the discharge pipe 25. The electric motor section D is controlled to an optimal operating frequency according to the load, and air conditioning can be performed under optimal conditions.

[0036] Also, especially during startup, automatic control is performed to perform high frequency operation so that the set temperature is reached in a short time. At this time, the three-way valve 27
9 and the release bypass pipe 29 are switched to communicate with each other.

A part of the high-pressure discharge gas discharged from the discharge pipe 25 is transferred from the release bypass pipe 29 to the three-way valve 27.
is led to the release pipe 19 through the release chamber 1.
5, the valve stopper 24 constituting the valve mechanism 21 is pressed.

The valve stopper 24 together with the check valve 23 closes the release ports 14 all at once. Therefore, the refrigerant gas compressed in the first and second compression chambers A and B is all discharged into the high-pressure discharge chamber 5 without being released, and is led from the discharge pipe 25 to the condenser of the refrigeration cycle. The amount of refrigerant circulated increases to maintain high compression efficiency.

After a certain amount of time has passed and the room temperature has stabilized close to the set temperature, the operation is gradually switched to low frequency operation, and at the same time, the three-way valve 27 is switched so that the release pipe 19 and the release pipe 28 communicate with each other.

Then, the check valve 23 opens from the point where high pressure is no longer applied to the valve mechanism 21, and a portion of the refrigerant gas that is being compressed in the first and second compression chambers A and B is released to each release port. 14...

[0041] This refrigerant gas is supplied to each release port 14...
from the release chamber 15 to the release pipe 19,
It is further released to the suction pipe 26 side. That is, the amount of refrigerant circulated in the refrigeration cycle is reduced, resulting in an operating state that matches the load.

As mentioned above, the fixed scroll blade 3
Two release ports 14, 14 are provided in the first compression chamber A that sucks refrigerant gas from the suction port 11 provided near the winding end S in the wing section 7, and the release port 14 is located at 180° from the winding end S. One release port 14 is provided in the second compression chamber B that sucks refrigerant gas from the suction ports 12 provided at opposing positions.

Therefore, the total cross-sectional area of the release ports 14 provided in the first compression chamber A is larger than the total cross-sectional area of the release ports 14 provided in the second compression chamber B.

Originally, as shown in FIG. 11, the first compression chamber A has a larger compression capacity contribution ratio than the second compression chamber B, but the total cross-sectional area of the release port 14 is set. Due to this relationship, the pressure balance in both the first and second compression chambers A and B is balanced.

In view of the compression capacity contribution ratio shown in FIG. 11, if the first and second compression chambers A and B are assumed to be at the same temperature, the present invention will be as shown in FIG. 10(A). With such a release, the differential pressure (Δp) between the first compression chamber A and the second compression chamber B can be considered to be zero. On the other hand, in the conventional one without a release, the differential pressure (Δp) between the first compression chamber and the second compression chamber is 0 of the release pressure Pm.
．． Proportional to 5 times.

From this, even when the compression ratio is low and high suction pressure operation (for example, about 10 kg/cm2 G) is performed, the stress applied to the blade section is lower than that of the conventional model, as shown in FIG. 10(B). A result was obtained in which the number of products with the release of the present invention was reduced to about 1/3 or less compared to the number of products without a release. (The pressure conditions in the figure are suction pressure 19 kg/
cm2G, and the discharge pressure is 25kg/cm2G. )

[
In the above embodiment, the rotor cover 36 is integrally attached to the pump case 37, and its peripheral end is connected to the rotor end ring 31a and the stator coil end 3.
0a.

As the main shaft 32 rotates, the liquid level of the lubricating oil collected at the inner bottom of the sealed case 1 rises, and the lubricating oil stirred by the rotor end ring 31a applies force to the stator coil end 30a. try However, since the rotor cover 36 is interposed between these, the stator coil end 36 is coated with lubricating oil.
The force acting on a can be blocked.

Furthermore, since the rotor cover 36 is integrated with the pump case 35 without intervening the main shaft 32, the rotor cover 36 and the main shaft 32 do not slide, thus eliminating mutual wear and sliding loss. improved reliability.

Further, in the above embodiment, the number of valve mechanisms 21 corresponding to the plurality of release ports 14 is provided, but the invention is not limited to this, and as shown in FIG. The pair of release ports 14a, 14a provided on the compression chamber A side have their open ends on the release chamber 15 side close to each other, and merge into a release merging port 14S provided on the open end side. The release merging port 14S may be opened and closed simultaneously by the same valve mechanism 21A.

Similarly, as shown in FIG. 9, the release ports 14 completely merge before the release merge port 14S.
b, 14b, the release merging port 14S may be opened and closed simultaneously by the same valve mechanism 21A. In any case, the number of valve mechanisms 21A can be reduced, improving reliability and ease of assembly, and reducing installation space. In addition, various modifications can be made within the scope of the gist of the present invention.

[0052]

According to the present invention, the first compression chamber compresses the compressed gas sucked from the suction port provided near the winding end of the wing portion of the fixed scroll blade; A second compression chamber is formed for compressing the gas to be compressed sucked in from a suction port provided at a position 180 degrees opposite from the second compression chamber, and from the total cross-sectional area of the release port provided in the second compression chamber, Since the total cross-sectional area of the release ports provided in the compression chambers has been increased, the pressure balance between the first and second compression chambers can be achieved, eliminating unbalance caused by gas pressure, and the compression ratio can be lowered to increase the Even during suction pressure operation, the blade stress is significantly reduced, preventing overcompression and suppressing input loss.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a scroll compressor showing one embodiment of the present invention.

FIG. 2 is a cross-sectional plan view of the scroll compression mechanism section of the same embodiment.

FIG. 3 is a longitudinal cross-sectional view of the release port portion of the same embodiment.

FIG. 4 is a cross-sectional plan view of a fixed scroll blade mirror plate portion of the same embodiment.

FIG. 5 is a plan view of a partition plate of the same embodiment.

FIG. 6 is a piping configuration diagram of the compressor in the same embodiment.

FIG. 7 is a longitudinal sectional view of the oil pump section of the same embodiment.

FIG. 8 is a schematic vertical sectional view of a release port portion showing another embodiment of the present invention.

FIG. 9 is a schematic vertical cross-sectional view of a release port portion of yet another embodiment.

FIG. 10(A) is a differential pressure characteristic diagram between an embodiment of the present invention and a conventional example. (B) is a wing stress characteristic diagram of an embodiment of the present invention and a conventional example.

FIG. 11 is a compression capacity contribution rate characteristic diagram for each compression chamber, showing a conventional example of the present invention.

[Explanation of symbols] 9, 10...Blade section, 3...Fixed scroll wing, 4...Orbiting scroll wing, S...End of winding (of the wing section of fixed scroll wing), 11...Suction port, A...First Compression chamber, 12...Suction port, B...Second compression chamber, 14...Release port.

Claims (1)

[Claims] [Claim 1] A fixed scroll wing and an orbiting scroll wing having spiral wing sections of the same shape are meshed with each other, whereby suction is drawn from a suction port provided near the winding end of the wing section of the fixed scroll wing. a first compression chamber that compresses the compressed gas that is drawn into the fixed scroll blade; and a second compression chamber that compresses the compressed gas that is sucked in from a suction port that is provided at a position 180 degrees opposite from the winding end of the fixed scroll blade. With,
In a scroll compressor that forms two symmetrical compression chambers, a release port is provided in each of the first compression chamber and the second compression chamber, and from the total cross-sectional area of the release port provided in the second compression chamber. , A scroll compressor characterized in that the total cross-sectional area of the release port provided in the first compression chamber is increased.