JPH11166490A - Displacement control scroll compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide highly efficient high performance like that shown in the drawing during full/part road running by providing a power saving mechanism and an over-compression preventing mechanism and setting an incorporated compression ratio decided by the geometrical shape of a spiral lap vortex to be optimal at the time of power save running. SOLUTION: An incorporated compression ratio between spiral laps 23 and 33 is set to be optimal under a standard condition during part road running. During full road running, a power saving mechanism 40 introduces high pressure coolant gas before flowing into a condenser to a bypass route 43, presses a bypass valve 46, shuts off a bypass hole 44 and a return hole 45 and prevents coolant gas in a compression room P from returning to a lower pressure room 2A side. Also, when a pressure in the compression room P increases more than that of a high pressure room 2B, coolant in the compression room P is leaked to the high pressure room 2B by the action of an over-compression preventing mechanism 50 composed of an over-compression bypass hole 51 and an over- compression bypass valve 52, and thus over-compression is prevented.

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 an air conditioner, a refrigerator and the like, and more particularly, to a power saving mechanism for controlling a capacity by bypassing a refrigerant gas during compression to a low pressure side. The capacity control scroll compressor that can secure the performance improvement by improving the illustration loss, recompression loss, and motor loss, the cost reduction by facilitating the workability, the sealing performance, and the reliability improvement by improving the starting characteristics. It is about.

[0002]

2. Description of the Related Art FIG. 9 shows, for example, Japanese Patent Application Laid-Open No. 8-303361.
FIG. 1 is a schematic explanatory view showing a state of piping to a unit circuit of a conventional capacity-controlled scroll compressor disclosed in Japanese Patent Application Publication No. JP-A-2006-15095.
As shown in FIG. 9, the compressor body 1 is connected to an external unit circuit 100, and the unit circuit 1
00 denotes a condenser 101, a decompression device 102, and an evaporator 10
The compressed high-pressure refrigerant gas discharged from the compressor body 1 is condensed and liquefied in the condenser 101, the liquid refrigerant is decompressed by the decompression device 102, and is vaporized in the evaporator 103 to perform a cooling action. Is performed, and then returned to the compressor body 1.

A part of the liquid refrigerant condensed and liquefied in the evaporator 101 is supplied from a liquid refrigerant pipe 104 into a compression chamber of a scroll compression element in the compressor main body 1 described later to raise the temperature of the compressed refrigerant. On the other hand, during full load (full load) operation and power save operation,
A high-pressure refrigerant gas or a low-pressure refrigerant gas before flowing into the condenser 101 is selectively opened by opening an electromagnetic valve 106 provided in the high-pressure inlet pipe 105, so that a back-pressure passage for a scroll compression element described later communicates with a bypass passage of a power saving mechanism. It is designed to be introduced into the pressure passage.

FIG. 10 is a schematic vertical sectional view showing the entire structure of a conventional displacement control scroll compressor disclosed in the above publication. As shown in FIG. 10, the compressor main body 1 includes a cylindrical middle shell 3 and an upper shell 4 and a lower shell 5 covered by upper and lower ends of the middle shell 3. A frame 6 is fixed to an upper portion, and a suction passage 7 for guiding the refrigerant gas into a compression chamber P, which will be described later, is formed on the outer periphery of the frame 6, while a sub-frame 8 is fixed to a lower portion thereof. 6 and a scroll compression element 20 driven by the electric element 10 is disposed above the main frame 6.

The electric element 10 comprises a stator 11, a rotor 12 rotatably inserted into the stator 11, and a shaft 13 forming a central shaft of the rotor 12. The scroll compression element 20 is composed of a fixed scroll 21 and an orbiting scroll 31 which are vertically opposed to each other. The spiral wrap 23 formed on the lower surface of the end plate 22 of the fixed scroll 21 is attached to the end plate 32 of the orbiting scroll 31.
A compression chamber P composed of a plurality of compression spaces is formed by meshing with a spiral wrap 33 formed on the upper surface of the compression chamber P.

That is, the oscillating scroll 31 has an eccentric shaft portion 1 having a boss-shaped bearing portion 34 provided at the upper end portion of the shaft 13 of the electric element 10 at the center of the lower surface of the end plate 32.
4, the fixed scroll 21 is revolved so as not to rotate with respect to the fixed scroll 21 driven by the electric element 10 and eccentrically moved, and the compression chamber P is moved from the outer low-pressure side compression space to the inner high-pressure side compression space. , The refrigerant gas flowing from the suction pipe 9A facing the low pressure chamber 2A side in the closed container 2 and compressed through the electric element 10 and the suction passage 7 is compressed, and the compressed refrigerant gas is compressed. Is discharged from the discharge port 24 communicating with the high pressure side of the compression chamber P formed at the center of the fixed scroll 21 to the high pressure chamber 2B side by opening the discharge valve 25, and sealed from the discharge pipe 9B communicating with the high pressure chamber 2B. It is configured to be discharged out of the container 2 and then condensed and liquefied in the condenser 101 as described above.

FIG. 11 is a schematic vertical sectional view showing a main part of a power saving mechanism in the conventional displacement control scroll compressor disclosed in the above publication. As shown in the drawing, the scroll compression element 20 is provided with a power save mechanism 40 for bypassing the refrigerant gas in the middle of compression to the low pressure side and controlling the capacity. The power save mechanism 40 is provided with a head plate 22 of the fixed scroll 21. A cover 41 provided on the upper surface of
The cover 41 has a back-pressure passage 42 through which the high-pressure refrigerant gas from the unit circuit 100 is supplied through a high-pressure introduction pipe 106, and a bypass passage that communicates with the back-pressure passage 42 via an introduction port 42a. The bypass passage 43 has a bypass hole 44 communicating with the compression chamber P formed through the end plate 22 of the fixed scroll 21.
And the return hole 45 communicating with the low-pressure chamber 2 </ b> A face as a pair,
The bypass passage 4 of the bypass hole 44 and the return hole 45
The openings 44a and 45a on the third side are inclined so as to be close to each other, and are opened and closed by the bypass valve 46.

The power save mechanism 40 keeps the solenoid valve 106 closed during part-load (power save) operation so that the high-pressure refrigerant gas before flowing into the condenser 101 does not flow into the bypass passage 43. On the other hand, during the full load operation, the high pressure refrigerant gas before flowing into the condenser 101 is introduced from the back pressure passage 42 into the bypass passage 43 by opening the solenoid valve 106, and the back pressure action by the high pressure refrigerant gas is performed. By depressing the bypass valve 46, the bypass hole 44 and the return hole 45 are shut off, so that the refrigerant gas in the compression chamber P does not return to the low-pressure chamber 2A side.

At the time of part-load operation, by introducing the low-pressure refrigerant gas into the back pressure passage 42, the bypass valve 46 is pushed up by the excessive pressure of the refrigerant gas being compressed and opened, and the refrigerant gas being compressed is bypassed. Return hole 4 from 44
By leaking to the low pressure chamber 2A side through 5, capacity control suitable for the refrigerating capacity is performed.

[0010]

Since the conventional displacement control scroll compressor is constructed as described above, the built-in compression ratio determined by the geometric shape of the spiral wraps 23, 33 is set at the time of full load operation. It was optimized so that excess / under-compression loss and over-compression loss were reduced under conditions of high operation frequency such as standard conditions. Therefore, during the part-load operation, substantial compression starts inside the bypass hole 44, which is the same as the reduction in the number of turns of the spiral wraps 23 and 33, and the built-in compression ratio is full. Since the compression loss was smaller than that during the load operation, the excess and deficiency compression loss increased.

This is illustrated in FIG.
Shows a PV diagram under the standard condition of the full load operation, and there is almost no over-compression loss or over-under compression loss. Further, the PV diagram at the time of the part-load operation is indicated by 201, and the number of turns of the spiral wraps 23 and 33 is substantially reduced,
The built-in compression ratio has become smaller, and the excess / deficiency compression loss 202 has increased.

Further, in the conventional capacity-controlled scroll compressor, when the electric element 10 is a single-phase induction motor, the capacity of the operation capacitor is set so that the motor efficiency becomes maximum during the full load operation. For this reason, during the part load operation in which the compressor capacity is small and the load is light, the set capacitor capacity is substantially large and is not appropriate, and the motor efficiency is reduced.

FIG. 13 illustrates this, and the motor efficiency becomes the maximum value ηm at the load torque Tf at the time of full load operation.
ax because the capacity of the operation capacitor is set to be optimal when the load torque is Tf as described above.
Since p is a very light load as compared with the full load operation, the motor efficiency is reduced to ηp because the capacity of the operation capacitor is larger than the load torque Tp.

Further, in the conventional capacity control scroll compressor, the scroll compression element 20 is provided with a partition wall for separating the inside of the closed casing 2 into a high pressure side and a low pressure side, so that the spring force by the elastic member and one of the back surfaces of the fixed scroll 21 are provided. In the case of a scroll compressor having a compliant mechanism that presses the fixed scroll 21 in the axial direction with the gas pressure of the high pressure space provided in the section, when the high pressure introduction pipe 105 is introduced in the axial direction from the upper shell 4 Due to the presence of the partition wall, there are three joining points, that is, the upper shell 4, the partition wall, and the fixed scroll 21, and processing and assembly are complicated.

When the high-pressure introducing pipe 105 is introduced from the radial direction of the closed vessel 2, the bypass passage 43 becomes long, and when refrigerant leaks into the low-pressure space, the pressure loss increases and the efficiency shown in the drawing decreases. Had a re-compression loss because of the dead volume.

Further, in the above-described scroll compressor with a compliant mechanism, when liquid compression occurs at the time of starting the compressor, the pressure in the compression chamber becomes larger than the pressing force on the back of the fixed scroll 21, and the fixed scroll 21 21 moves upward in the axial direction, reduces the pressure in the compression chamber, returns to the normal position of the fixed scroll 21 again, and moves up and down in the axial direction until a steady state where liquid compression is not performed. For this reason,
Since there is a possibility that the high-pressure introduction pipe 105 may be repeatedly subjected to stress and cause fatigue failure, it is not easy to secure the reliability of the high-pressure introduction pipe 105.

Further, in the conventional capacity-controlled scroll compressor, the high-pressure inlet pipe 105 was required for switching between full load operation and part load operation. For this reason, in the compressor, the high pressure introduction pipe 105 is connected to the power saving mechanism 4.
The number of joints such as welding, bolting, caulking, etc. increases in order to join with 0, processing and assembly are complicated, and it is necessary to secure the high pressure inlet pipe 105 and the solenoid valve 106 on the external unit side and secure piping management space. This has led to increased costs and larger units.

The present invention has been made to solve such a problem, and an object of the present invention is to provide a high-capacity scroll compressor having a high efficiency in illustration in both full load operation and part load operation.

It is another object of the present invention to obtain a high-performance capacity-controlled scroll compressor having high motor efficiency at full load operation and part load operation.

It is another object of the present invention to provide a high-performance capacity control scroll compressor having a high power save ratio and a small recompression loss.

It is another object of the present invention to provide a capacity-controlled scroll compressor which is easy to process and assemble, has high reliability in a high-pressure inlet pipe, and has high performance, high reliability and low cost.

Another object of the present invention is to obtain a lower-cost capacity control scroll compressor by using a low-cost bypass valve that does not require a sealing means such as an O-ring and has no O-ring groove processing.

Further, the reliability of the power saving mechanism which does not require a high pressure introducing pipe is high, and the processing and assembly for joining the high pressure introducing pipe to the power saving mechanism can be simplified. An object of the present invention is to provide a displacement-controlled scroll compressor that does not require welding of an electromagnetic valve, can easily secure piping management space, and can reduce the cost and the size of the unit.

[0024]

SUMMARY OF THE INVENTION A capacity control scroll compressor according to the present invention has an electric element housed in a closed container, and a fixed scroll and an orbiting scroll housed in the closed container. A scroll compression element that forms a compression chamber composed of a plurality of compression spaces by meshing spiral wraps formed opposite to the end plates of the fixed scroll and the orbiting scroll, respectively, and a refrigerant gas that is being compressed in the compression chamber. A power saving mechanism for controlling the capacity by bypassing the gas from the bypass hole to the low pressure side, and an overcompression bypass hole and an overcompression bypass valve for bypassing the gas in the compression chamber during compression to the high pressure side during full load operation. With an overcompression prevention mechanism that has a built-in compression ratio determined by the spiral wrap spiral geometry during power save operation. Condensation, is obtained by setting as excessive compression loss is small becomes optimum.

[0025] Further, an electric element comprising a single-phase induction motor housed in a sealed container and having a main winding and an auxiliary winding on a stator winding, and a unit connected in series to the auxiliary winding of the electric element, The operation capacitor for full load operation with the optimum capacitor capacity during the full load operation on the side and the operation capacitor for power save operation with the optimum capacitor capacity during the power save operation on the unit side, connected in series with the auxiliary winding of the electric element And a mechanism for switching between a full-load operation capacitor and a power-save operation capacitor in conjunction with switching between a full-load operation and a power-save operation.

Further, the electric scroll includes a motorized element housed in a sealed container and a fixed scroll and a swinging scroll housed in the sealed container. The fixed scroll and the orbiting scroll are formed so as to face each other. A scroll compression element that forms a compression chamber composed of a plurality of compression spaces by meshing the spiral wraps with each other, and a partition wall that separates the interior of the closed container into a high-pressure side and a low-pressure side, and has an elasticity. A compliant mechanism that presses the fixed scroll in the axial direction with the spring force of the member and the gas pressure of the high-pressure space provided in a part of the fixed scroll back surface, and compresses the refrigerant gas in the middle of compression in the compression chamber from the compression chamber in the axial direction. And a power saving mechanism for performing capacity control by bypassing to a low-pressure side from a bypass hole that passes to a low-pressure side.

A bypass valve provided in the power save mechanism and using a piston valve. A high pressure refrigerant gas is guided from the unit circuit to the power save mechanism to close the bypass valve by pressing a back surface of the bypass valve. And a high-pressure inlet pipe whose part is joined to the partition wall.

The piston valve is formed of an elastic member.

Further, there are a motorized element housed in the closed container and a fixed scroll and a swinging scroll housed in the closed container. The fixed scroll and the swinging scroll are respectively formed so as to face the end plates of the fixed scroll and the swinging scroll. A scroll compression element that forms a compression chamber composed of a plurality of compression spaces by meshing the spiral wraps that are formed with each other, and a power that controls the capacity by bypassing the refrigerant gas during compression in the compression chamber from the bypass hole to the low pressure side. It is provided with a save mechanism and a bypass valve provided in the power save mechanism and constituted by an electromagnetic valve provided in a closed container.

[0030]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 Hereinafter, an example of an embodiment of the present invention will be described with reference to the drawings. FIG.
BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a view showing an example of an embodiment of the present invention and is a longitudinal sectional view of a main part of a displacement control scroll compressor. This compressor body has the same structure as the conventional capacity-controlled scroll compressor except that the built-in compression ratio of the spiral is set to be optimal during part-load operation, and that it has an over-compression prevention mechanism. .

A frame 6 is fixed to an upper portion in a closed container 2 formed by a cylindrical middle shell 3 and an upper shell 4 and a lower shell (not shown) covered at upper and lower ends of the middle shell 3. A suction passage (not shown) for guiding the refrigerant gas into a compression chamber P, which will be described later, is formed on the outer periphery of the frame 6, and a sub-frame 8 is fixed to a lower portion of the suction passage. An electric element (not shown) is supported between the frame and the frame 6, and a scroll compression element 20 driven by the electric element is arranged above the frame 6.

The electric element comprises a stator, a rotor rotatably inserted into the stator, and a shaft forming a central shaft of the rotor. The fixed scroll 21 includes a fixed scroll 21 and an orbiting scroll 31 which are vertically opposed to each other.
The spiral wrap 23 formed on the lower surface of the first end plate 22 and the spiral wrap 33 formed on the upper surface of the end plate 32 of the orbiting scroll 31 are engaged with each other, thereby forming the compression chamber P including a plurality of compression spaces. Has formed.

That is, the orbiting scroll 31 is mounted on the end plate 3
A boss-shaped bearing portion 34 formed in the center of the lower surface of the motor 2 is aligned with an eccentric shaft portion provided at the upper end of the shaft of the electric element, so that the fixed scroll 21 does not revolve around the fixed scroll 21 driven by the electric element. By causing the compression chamber P to gradually reduce from the outer low-pressure side compression space toward the inner high-pressure side compression space, the suction pipe (shown in FIG. ) Is compressed from the discharge port 24 communicating with the high-pressure side of the compression chamber P formed at the center of the fixed scroll 21 by compressing the refrigerant gas flowing from the electric scroll and supplied through the electric element and the suction passage. When the discharge valve 25 is opened, the liquid is discharged to the high-pressure chamber 2B side, discharged from the discharge pipe 9B communicating with the high-pressure chamber 2B to the outside of the closed vessel 2, and condensed and liquefied.

The scroll compression element 20 is provided with a power save mechanism 40 for controlling the capacity by bypassing the refrigerant gas in the middle of compression to the low pressure side. A cover 41 is provided on the upper surface, and the cover 41 is provided with a high-pressure refrigerant gas from the unit circuit 100.
Back pressure passage 42 supplied through the
Is formed with a bypass passage 43 communicating with the low pressure chamber 2A through the inlet 42a. The bypass passage 43 communicates with the compression chamber P formed through the end plate 22 of the fixed scroll 21 and communicates with the low pressure chamber 2A. Return hole 45
And the bypass hole 44 and the return hole 4
The opening 44a, 45a on the side of the bypass passage 43 in FIG.

The power saving mechanism 40 prevents the high-pressure refrigerant gas before flowing into the condenser from flowing into the bypass passage 43 during the part-load (power-save) operation. The high-pressure refrigerant gas before flowing into the bypass passage 43 is introduced from the back-pressure passage 42 into the bypass passage 43, and the bypass valve 46 is depressed by the back-pressure action of the high-pressure refrigerant gas.
The return hole 45 is shut off to prevent the refrigerant gas in the compression chamber P from returning to the low-pressure chamber 2A.

When the pressure in the compression chamber P rises higher than the pressure in the high-pressure chamber 2B, the over-compression prevention mechanism 50 composed of the over-compression bypass hole 51 and the over-compression bypass valve 52 causes the inside of the compression chamber P Leaks into the high-pressure chamber 2B, it is possible to prevent over-compression.

At the time of part-load operation, by introducing the low-pressure refrigerant gas into the back pressure passage 42, the bypass valve 46 is pushed up by the excessive pressure of the refrigerant gas in the middle of compression and opened, and the refrigerant gas in the middle of the compression is bypassed. Return hole 4 from 44
By leaking to the low pressure chamber 2A side through 5, capacity control suitable for the refrigerating capacity is performed.

Here, since the built-in compression ratio of the spiral wraps 23 and 33 is set to be optimal under the standard conditions during the part-load operation, the over / under compression loss and the over compression loss can be reduced. It becomes possible.

As is clear from the above description, since the built-in compression ratio of the spiral wraps 23 and 33 is set to be optimal under standard conditions during part-load operation,
In this case, the PV diagram has almost no over / under compression loss and no over compression loss as indicated by 205 in FIG. Also, the PV diagram at the time of full load operation is shown at 206, where the over-compression prevention mechanism 50 also causes almost no over-compression loss or over-under compression loss. In other words, it is possible to obtain a high-performance capacity-controlled scroll compressor having high efficiency in both the full load operation and the part load operation.

Embodiment 2 Hereinafter, another example of the embodiment of the present invention will be described with reference to the drawings. FIG. 3 is a diagram showing another example of the embodiment of the present invention, and is a circuit configuration diagram of a capacity control scroll compressor. The electric element is formed of a single-phase induction motor having a main winding 300 and an auxiliary winding 301 on a stator winding, and is connected in series to the auxiliary winding 301. Are connected in parallel to each other and are connected in parallel with an operation capacitor that is always energized during operation.
rf302, operation capacitor Crp for part-load operation
303, a full-load operation capacitor Crf for maximizing the motor efficiency with the load torque during the full-load operation in conjunction with switching between the unit-side full-load operation and the power save operation; A mechanism is provided to switch using the relay 304 or the like to the part load operation operation capacitor CRp that maximizes the motor efficiency with the load torque during the part load operation.

From the above, as shown in FIG. 4, during the full load operation, the load torque Tf and the operation capacitor Cr
Since f is set to be optimal, the motor efficiency becomes max at ηf, and the motor efficiency is compared with ηf because the load torque Tp and the operation capacitor CRp are set to be optimal even during part-load operation. Ηp with almost no reduction. That is, it is possible to obtain a high-performance capacity-controlled scroll compressor with high motor efficiency in both full load operation and part load operation.

Embodiment 3 Hereinafter, another example of the embodiment of the present invention will be described with reference to the drawings. FIG. 5 is a view showing another example of the embodiment of the present invention, and is a longitudinal sectional view of a main part of a displacement control scroll compressor. The scroll compression element 20 includes a partition wall 60 that separates the inside of the closed vessel 2 into a high pressure side and a low pressure side, and the spring force of the elastic member 61 and the gas pressure of the high pressure space 62 provided on a part of the back surface of the fixed scroll 21 are used. In a scroll compressor having a compliant mechanism that presses the fixed scroll 21 in the axial direction, a power saving mechanism 40 for a capacity control bypass is provided with a bypass passage 43 provided so as to pass from the compression chamber to the low pressure side in the axial direction. It is constituted by a piston-shaped bypass valve 63.

Further, the joining portion of the high-pressure introduction pipe 105 in the closed vessel 2 is provided on the partition wall 60. Thereby, the bypass passage 43 is very short, and the pressure loss when the refrigerant being compressed during the part load operation leaks to the low pressure side through the bypass passage 43 can be reduced.
Can be made very small. In other words, the power saving ratio during capacity control can be increased, and the recompression loss can be reduced because the volume of the bypass passage serving as a dead volume is very small.

Since the high-pressure inlet tube 105 is joined to the partition wall 60, the fixing point such as welding is fixed to the upper shell 4 and the partition wall 6
0, and the high-pressure introduction pipe 105
Is not directly fixed to the fixed scroll 21, so that no repetitive stress is exerted by the vertical movement of the fixed scroll 21 in the axial direction during liquid compression. Thereby, the reliability of the high-pressure introduction pipe can be improved.

The bypass valve 6 shown in FIG.
3 is configured in a piston shape and connects the bypass passage 43 of the fixed scroll 21 and the high-pressure introduction pipe 105,
It is possible to follow the above-mentioned vertical movement of the fixed scroll, and a seal can be secured. Here, the case where the piston-shaped bypass valve 63 is made of a metal such as iron is shown, and the radial seal is sealed with an O-ring 63a, but other sealing means may be used. .

Further, the material of the piston-like bypass valve 63 may be made of an elastic member such as Teflon or rubber. In this case, the seal can be formed as shown in FIG. 7 without using an O-ring. Becomes possible.

As described above, the capacity control scroll which is easy to process and assemble, has a high power saving rate, has a small recompression loss, has high reliability of the high-pressure inlet tube 105, and has high performance, high reliability and low cost. You can get a compressor.

When the piston-like bypass valve 63 is made of an elastic material such as Teflon or rubber,
A sealing means such as a ring 63a is not required, and a low-cost bypass valve 63 without O-ring groove processing can be obtained. Thus, a capacity-controlled scroll compressor lower in cost than the compressor can be obtained.

Embodiment 4 Hereinafter, another example of the embodiment of the present invention will be described with reference to the drawings. FIG. 8 is a view showing another example of the embodiment of the present invention, and is an enlarged vertical sectional view of a main part of a displacement control scroll compressor. Bypass passage 4
3 and a piston-like bypass valve 63, the bypass valve 63 is connected to a solenoid 64.
It is configured by an electromagnetic valve using such as provided in a closed container.

In the conventional capacity-controlled scroll compressor, the high-pressure inlet pipe 105 and the solenoid valve 106 were required for switching between the full load operation and the part load operation, but the bypass valve 63 itself is an electromagnetic valve. The opening and closing of the bypass hole can be performed directly, and the high-pressure introduction pipe 105 is opened.
Is not required. This also increases the reliability of the power save mechanism because one valve is eliminated.

Furthermore, since the high pressure introducing pipe 105 is joined to the power saving mechanism 40 on the compressor side, there is no need to join such as welding, bolting, caulking, etc., so that the processing and assembly can be simplified, and the high pressure introducing on the external unit side. Welding of pipes and solenoid valves is eliminated, and space for piping management can be easily secured, so that costs can be reduced and units can be downsized. That is, a low-cost and highly reliable capacity control scroll compressor can be obtained.

[0052]

According to the displacement control scroll compressor according to the present invention, a high performance displacement control scroll compressor having a high efficiency in drawing both in full load operation and in part load operation can be obtained.

Further, it is possible to obtain a high-performance capacity-controlled scroll compressor having high motor efficiency in both full load operation and part load operation.

Further, it is possible to obtain a high-performance capacity-controlled scroll compressor having a high power saving ratio and a small recompression loss.

Further, it is possible to obtain a high-performance, high-reliability, low-cost capacity-controlled scroll compressor which is easy to process and assemble, has high reliability for the high-pressure introduction pipe.

Further, since the piston-like bypass valve is made of an elastic member, no sealing means is required, and a low-cost bypass valve which does not require processing for the sealing means can be obtained. A capacity control scroll compressor can be obtained.

Further, since the bypass valve is constituted by an electromagnetic valve and provided in a closed container, a low-cost and highly reliable displacement control scroll compressor can be obtained.

[Brief description of the drawings]

FIG. 1 is a view showing a first embodiment of the present invention, and is a longitudinal sectional view of a main part of a displacement control scroll compressor.

FIG. 2 is a diagram showing the first embodiment of the present invention, and is a PV diagram of the displacement control scroll compressor.

FIG. 3 is a diagram illustrating a second embodiment of the present invention, and is a circuit configuration diagram of a displacement control scroll compressor.

FIG. 4 is a view showing a second embodiment of the present invention, and is a graph showing a relationship between the number of revolutions of the displacement control scroll compressor, the motor efficiency, and the torque.

FIG. 5 is a view showing a third embodiment of the present invention, and is a longitudinal sectional view of a main part of a displacement control scroll compressor.

FIG. 6 is a view showing a third embodiment of the present invention, and is an enlarged longitudinal sectional view of a main part of a displacement control scroll compressor.

FIG. 7 is a view showing a third embodiment of the present invention, and is an enlarged longitudinal sectional view of a main part of a displacement control scroll compressor.

FIG. 8 is a view showing a fourth embodiment of the present invention, and is an enlarged longitudinal sectional view of a main part of a displacement control scroll compressor.

FIG. 9 is a schematic explanatory diagram showing a state of piping to a unit circuit of a conventional displacement control scroll compressor.

FIG. 10 is a schematic longitudinal sectional view showing the entire configuration of a conventional displacement control scroll compressor.

FIG. 11 is a schematic vertical sectional view showing a main part of a power saving mechanism in a conventional capacity control scroll compressor.

FIG. 12 is a PV diagram of a conventional displacement control scroll compressor.

FIG. 13 is a graph showing a relationship between the number of revolutions, the motor efficiency, and the torque in a conventional displacement control scroll compressor.

[Explanation of symbols]

1 Compressor body, 2 sealed container, 2A low pressure chamber, 2B
High pressure chamber, 9A suction pipe, 9B discharge pipe, 10 electric elements, 20 scroll compression element, 21 fixed scroll, 22 end plate, 23 lap, 24 discharge port, 3
1 oscillating scroll, 32 end plate, 33 wrap, 40
Power save mechanism, 41 cover, 42 back pressure passage, 4
3 bypass passage, 44 bypass hole, 45 return hole, 4
6 bypass hole, 47 valve body, 50 overcompression prevention mechanism,
51 over-compression bypass hole, 52 over-compression bypass valve, 6
0 partition wall, 61 elastic member, 62 high-pressure space, 63
Piston-shaped bypass valve, 63a O-ring, 63b
A piston-shaped bypass valve made of an elastic member, 64 solenoids.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Yoshinori Shirato 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsubishi Electric Corporation

Claims (6)

[Claims] An electric element housed in a closed container, and a fixed scroll and an orbiting scroll housed in the closed container. The fixed scroll and the orbiting scroll face each other. A scroll compression element that forms the compression chamber composed of a plurality of compression spaces by meshing the formed spiral wraps with each other, and controls the capacity by bypassing the refrigerant gas during compression in the compression chamber from the bypass hole to the low pressure side. A power saving mechanism for performing the operation, and an over-compression prevention mechanism having an over-compression bypass hole and an over-compression bypass valve for bypassing the gas in the compression chamber during compression to a high pressure side during full load (full load) operation. With the built-in compression ratio determined by the spiral wrap spiral geometry, over / under compression and over compression loss during power save operation are reduced. A capacity control scroll compressor characterized by being set to be optimal. 2. An electric element, which is housed in a closed container and includes a single-phase induction motor having a main winding and an auxiliary winding on a stator winding, and connected in series to an auxiliary winding of the electric element; An operation capacitor for full load operation having an optimum capacitor capacity during the full load operation on the unit side, and a power save operation operation having an optimum capacitor capacity during the power save operation on the unit side, connected in series to the auxiliary winding of the electric element. A capacitor, and a mechanism for switching between the full-load operation capacitor and the power-save operation capacitor in conjunction with switching between the full-load operation and the power-save operation. Capacity control scroll compressor. 3. An electric element housed in a closed container, and a fixed scroll and an orbiting scroll housed in the closed container. The fixed element and the orbiting scroll face each other. A scroll compression element that forms a compression chamber composed of a plurality of compression spaces by meshing the formed spiral wraps with each other; and a partition wall that separates the inside of the closed container into a high-pressure side and a low-pressure side by the scroll compression element. A compliant mechanism that presses the fixed scroll in the axial direction by a spring force of an elastic member and a gas pressure of a high-pressure space provided on a part of the fixed scroll rear surface; And a power saving mechanism for performing capacity control by bypassing to the low pressure side from a bypass hole that passes from the compression chamber to the low pressure side in the axial direction. Characterized capacity control scroll compressor. 4. A bypass valve provided in the power saving mechanism and using a piston valve; and a high pressure refrigerant gas is supplied from the unit circuit to the power saving mechanism to press a back surface of the bypass valve to close the bypass valve. The capacity-controlled scroll compressor according to claim 3, further comprising: a high-pressure inlet pipe whose leading end is joined to the partition wall. 5. The displacement control scroll compressor according to claim 4, wherein said piston valve is formed of an elastic member. 6. An electric element housed in an airtight container, and a fixed scroll and an orbiting scroll housed in the airtight container. The electric element is opposed to the end plates of the fixed scroll and the orbiting scroll. A scroll compression element that forms the compression chamber composed of a plurality of compression spaces by meshing the formed spiral wraps with each other, and controls the capacity by bypassing the refrigerant gas during compression in the compression chamber from the bypass hole to the low pressure side. A capacity control scroll compressor, comprising: a power saving mechanism for performing the operation; and a bypass valve provided in the power saving mechanism and configured by an electromagnetic valve provided in a closed container.