JP3457689B2 - Refrigeration system with scroll compressor - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerating apparatus having a scroll compressor as a compressor constituting a refrigerating cycle in, for example, an air conditioner. 2. Description of the Related Art For example, in a compressor constituting a refrigeration cycle of an air conditioner, motion noise is extremely low as compared with a normal rotary compressor, and a suction valve and a discharge valve are not required. Scroll compressors that require a small number of parts and have good compression performance tend to be frequently used. In this type of scroll compressor, a spiral wing of a fixed scroll wing and a spiral wing of a revolving scroll wing mesh with each other, and a pair of wings of each scroll wing and a head plate are formed. A compression space is formed, and the orbiting scroll blades are orbited to suck refrigerant gas into the compression space and compress it. The gas that has risen to a predetermined pressure and has a high pressure is discharged from a discharge port provided in the center of the fixed scroll blade end plate, which is the center of the compression space. [0004] The compressor may be a low-pressure compressor in which a closed case is filled with a low-pressure refrigerant gas evaporated by an evaporator or a high-pressure refrigerant gas compressed in a compression space from a discharge port through a closed case. There is a high pressure type inside the case that is filled inside. [0005] By the way, in this scroll type compressor, in a state of being discharged from a discharge port,
The gas has a high pressure and a high temperature. for that reason,
Regardless of the low pressure type inside the case or the high pressure type inside the case, the temperature rises from the fixed scroll blade end plate around the discharge port through which the high-temperature gas is conducted. This high-temperature thermal effect is transmitted not only to the entire end plate portion but also to the wing portion integrated therewith. The wings are
Since the plate has only a relatively small thickness, it is deformed due to thermal expansion, and if the amount of deformation is large, the orbiting scroll blades come into strong contact with each other, which may cause friction or lock. Naturally, the orbiting scroll blades that mesh with the fixed scroll blades also have a thermal effect, and further expand to the support frame that supports the orbiting scroll blades in a freely rotatable manner, thereby increasing the temperature of the entire compression mechanism. Therefore, by cooling the fixed scroll blade serving as a high-temperature source, not only the orbiting scroll blade but also the entire compression mechanism can be cooled, which leads to improvement in operation reliability. For example, Japanese Patent Publication No. 63-58272
In this publication, a tank is manufactured separately and mounted on the upper surface of a fixed scroll end plate. [0008] The tank is communicated with an injection pipe on the condenser outlet side of the refrigeration cycle, and is filled with a high-pressure liquid refrigerant. This liquid refrigerant is guided to the intermediate pressure portion of the compression space via the injection hole. Therefore, the end plate portion of the fixed scroll blade is cooled by receiving heat conduction of the liquid refrigerant filled in the tank. The enthalpy of the liquid refrigerant is as low as the enthalpy at the inlet of the evaporator, and the enthalpy of the gas discharged from the discharge port is significantly reduced by mixing the injected liquid refrigerant into the gas being compressed, thereby reducing the temperature. Go down. Although such a cooling effect is obtained, the tank structure and the mounting and fixing of the tank to the fixed scroll blades are complicated, and it takes time to ensure the sealing between the tank and the fixed scroll blades and the inside of the sealed case. There is a problem such as this. The present invention has been made in view of the above circumstances, and a first object of the present invention is to provide a simple and effective structure for a fixed scroll blade by adding a simple structure in a scroll compressor. It is an object of the present invention to provide a refrigeration apparatus having a scroll compressor that maintains a high cooling efficiency and prevents thermal adverse effects on the entire compression mechanism as well as the orbiting scroll blades. A second object is to provide a refrigeration system equipped with a scroll compressor capable of improving the injection efficiency without lowering the refrigeration capacity when the liquid refrigerant is injected into the compression space. It is. The present invention, which satisfies the above objects , comprises a fixed scroll wing and an orbiting scroll wing, and supplies a refrigerant gas to a pair of compression spaces formed by these. Injection to form a refrigeration cycle circuit consisting of a scroll compressor that sucks, compresses and discharges, a condenser, a decompression device, and an evaporator, and guides a part of the liquid refrigerant derived from the condenser to the scroll compressor. A circuit is provided, comprising an arc-shaped concave groove provided on the outer peripheral portion of the discharge port on the rear surface of the head plate portion of the fixed scroll blade, and a partition plate mounted on the rear surface of the head plate portion and covering the concave groove , forming a concave groove . Outer wall radius
In a case provided with a refrigerant reservoir for collecting the liquid refrigerant guided from the injection circuit through a guide port provided through in the direction , and an injection hole communicating the refrigerant reservoir with each compression space . A refrigerating apparatus provided with a low-pressure scroll type compressor, wherein said injection hole is a fixed scroll type.
The refrigerant reservoir and each compression space communicate with the
Has rotated more than 40 ° in crank angle since the suction was completed.
Compression set the opening position is provided in pairs in the space, on the time
Fixed scroll to cover the discharge port and partition plate
A valve that is fixed to the end plate of the wing to form a sealed discharge space
A cover is provided, and a discharge refrigerant pipe opens in the discharge closed space.
It is provided by mouth. According to the present invention , the liquid refrigerant guided from the injection circuit is collected in the refrigerant reservoir provided on the fixed scroll blade, and cools the fixed scroll blade. further,
The liquid refrigerant is injected into the compression space via the injection hole, and cools the orbiting scroll blades and the entire compression mechanism from the compression space. Further according to the invention ,
Since the position of the injection hole is set, there is no reduction in performance at low suction pressure. An embodiment of the present invention will be described below with reference to the drawings. FIG. 4 shows a refrigeration cycle of the air conditioner. In FIG. 1, reference symbol A denotes a scroll compressor described later. A condenser B, a capillary tube C as a decompression device, and an evaporator D are connected to the discharge portion Aa in this order through a refrigerant pipe P. The refrigeration cycle circuit R is formed by communicating from the evaporator D to the suction portion Ab of the compressor A. One end of a bypass pipe Pa constituting an injection circuit I is connected to an intermediate portion of the refrigerant pipe P which communicates the condenser B with the capillary tube C. An auxiliary capillary tube b is provided in the middle of the bypass pipe Pa, and the other end is connected to the compressor A as described later. FIG. 1 shows a part of the scroll compressor A. In the figure, reference numeral 1 denotes a sealed case, and a support frame 2 is provided in an upper portion of the sealed case 1 and rotatably supports a rotating shaft 3. The rotary shaft 3 is connected to a compression mechanism 4 to be described later, and a motor unit 7 including a stator 5 and a rotor 6 is provided below. The compression mechanism 4 is provided with the support frame 2.
And an orbiting scroll blade 11 rotatably supported by the support frame 2 via an Oldham ring 10, and a fixed scroll blade 12 meshed with the orbiting scroll blade 11. The Oldham ring 10 restricts the rotation of the orbiting scroll wing 11 and performs only the orbiting motion. The orbiting scroll blade 11 is provided with a mirror plate 11a having a boss 11c which engages with the upper end eccentric portion 3a of the rotary shaft 3, and a spiral-shaped scroll member integrally formed on the upper surface of the mirror plate 11a. And wings 11b. The fixed scroll blade 12 is provided with a head 12
a and a spiral wing portion 12b integrally projecting from the lower surface of the end plate portion 12a and meshing with the wing portion 11b of the orbiting scroll wing 11. These orbiting and fixed scroll blades 11 and 12
A pair of compression spaces S is formed by the end plates 11a, 12a and the wings 11b, 12b, which take in refrigerant gas from the peripheral end side, move to the center side, reduce the volume thereof, and perform the compression action. Can be done. A discharge port 15 is provided through the center of the fixed scroll end plate 12a so as to communicate with the spiral center of the compression space S. Further, a circular concave groove is provided around the concave portion where the discharge port 15 is provided, leaving a part, that is, a circular part partially missing in a plan view. This concave groove is provided in the partition plate 16 mounted on the upper surface of the fixed scroll blade end plate portion 12a.
The closed space is referred to as a refrigerant reservoir 17. As shown in FIG. 1 again, a valve cover 18 is mounted and fixed on the upper surface of the mirror plate portion 12a via the partition plate 16, and a closed space is formed above the discharge port 15. A part of the side face of the coolant reservoir 17 is provided with a head plate 1.
Guide port 19 provided horizontally from the outer peripheral surface of 2a
Is opened, and the end of the bypass pipe Pa provided through the closed case 1 is inserted and fitted therein. Therefore, the refrigerant sump 17 is provided with the injection circuit I
The liquid refrigerant guided from the tank is collected. A pair of injection holes 20, 20 are opened on the lower surface side of the refrigerant reservoir 17. That is, the injection holes 20, 20 are provided in the end plate portion 12a.
To the compression space S which is the lower surface. To be more specific, the opening position of each injection hole 20 facing the compression space S is determined when the completion of the gas suction in each compression space S is equal to the crank angle 0 of the rotary shaft 3.
When the angle is set to °, it is necessary to set the position to be opposed only when the crank angle becomes 40 ° or more. A refrigerant pipe P, which forms the suction portion Ab and communicates with the evaporator D, is connected to a lower side surface of the closed case 1. In the upper part of the sealed case 1, a refrigerant pipe P communicating with the condenser B penetrates to form the discharge part Aa. The refrigerant pipe P is connected to the fixed scroll end plate 12a, and opens on the peripheral surface of the concave portion where the discharge port 15 is provided. In the refrigerating apparatus provided with the scroll compressor A constructed as described above, when the electric motor unit 7 is energized to drive the compression mechanism unit 4, the low pressure from the suction part Ab of the refrigerant pipe P is discharged. Refrigerant gas is introduced into the closed case 1 and fills the internal space. This refrigerant gas is sucked into the outer peripheral side of the compression space S formed by the orbiting scroll blades 11 and the fixed scroll blades 12 via the gas guide path 21 provided in the support frame 2. The orbiting scroll blades 11 are gradually transferred to the center with the orbital motion of the orbiting scroll blades 11 and are compressed due to a decrease in space capacity. When the pressure has risen to a predetermined pressure, the high-pressure gas discharged from the discharge port 15 into the valve cover 18 and filled therein is transferred to an external condenser B via a refrigerant pipe P which is a discharge part Aa connected thereto. Be guided. The high-pressure gas is condensed and liquefied in the condenser B, guided to the capillary tube C, adiabatically expanded, and guided to the evaporator D to evaporate. At this time, heat exchange is performed with the air to be conditioned and air is cooled in the air conditioned room. The refrigerant gas evaporated in the evaporator D and reduced in pressure is guided again along the refrigerant pipe P, which is the suction portion Ab of the scroll compressor A, and fills the closed case 1 to fill the above described case. Is repeated. A part of the high-pressure liquid refrigerant derived from the condenser D is guided to an injection circuit I.
That is, it is branched into the bypass pipe Pa, reduced to a predetermined pressure by the auxiliary capillary tube b, and introduced into the scroll compressor A. In the scroll compressor A, the bypass pipe Pa passes through the sealed case 1 and the fixed scroll blade 12
The liquid refrigerant is collected here from a place communicating with the refrigerant reservoir 17 provided in the end plate part 12a. On the other hand, since the gas refrigerant which has been compressed in the compression space S and has become high pressure and high temperature is discharged from the discharge port 15, the surrounding end plate 12a becomes high temperature under the influence of heat, and furthermore, the entire end plate 12a , The wing portion 12b and the orbiting scroll wing 11 meshing therewith. However, the liquid refrigerant collected in the refrigerant reservoir 17 efficiently cools the end plate portion 12a of the fixed scroll blade 12 and lowers the temperature. Not only that,
The wing portion 12b is also cooled, and the cooling effect extends to the entire orbiting scroll wing 11 and the support frame 2 that mesh with the wing portion 12b. The liquid refrigerant filling the refrigerant sump 17 is:
Each of the opposing compression spaces S, S is injected from a pair of injection holes 20, 20. The supplied amount is supplied from the injection circuit I, and a constant liquid refrigerant is constantly collected in the refrigerant reservoir 17. As shown schematically in FIG. 3, the orbiting scroll blades 11 make a orbital motion and a compression action is performed. That is, (0 °) in the upper left of the figure means that the crank angle of the rotating shaft 3 is set to 0 ° as a reference. Here, the turning outer end portion of the volute portion 11b is in contact with the side surface of the stationary scroll blade portion 12b, a pair of compression spaces S, S gas is taken into the suction
The process is completed. And the rotating shaft 3 rotates,
In the drawing, the crank angle increases in the direction of the arrow, and the compression process is performed to simultaneously compress the gas taken into each of the compression spaces S. At a crank angle of 0 °, the injection holes 20, 20 are still at positions where they do not open into the compression spaces S, S. Based on this position, the crank angle is set to 40
° or more, the injection holes 20, 20 face the respective compression spaces S, S for the first time.
The liquid refrigerant collected in 7 is injected. That is, the crank angle is from 0 ° to 40 °
The period up to is the initial timing when the suction stroke is completed and the process shifts to the compression stroke, and each of the compression spaces S has only a relatively low pressure. In this state, the liquid refrigerant in the refrigerant reservoir 17 has not been supplied yet, so that a decrease in capacity can be avoided. When the crank angle exceeds 40 °, the compression action in each of the compression sections S, S advances to some extent, and the pressure increases. Here, since the liquid refrigerant from the refrigerant reservoir 17 is injected, the inside of the compression spaces S, S is cooled, and the temperature rise accompanying the compression action is suppressed. After all, the compression mechanism 4
Effective cooling with respect to the temperature and preventing a decrease in the refrigerating capacity, so that the exercise with the so-called improved COP can be performed. As described above, according to the present invention , the refrigerating cycle circuit provided with the scroll compressor and a part of the liquid refrigerant derived from the condenser are transferred to the scroll compressor. An injection circuit for guiding, a refrigerant reservoir is provided on a fixed scroll blade of the scroll compressor to collect liquid refrigerant guided from the injection circuit, and the refrigerant reservoir and each compression space communicate with each other via an injection hole . Refrigerant pool
The fixed scroll end plate has a groove with an open top.
Since the upper surface opening is opened with a partition plate ,
The simple structure inside the scroll compressor has a new partition plate.
Although it is relatively easy to obtain the refrigerant reservoir simply by adding the refrigerant , it maintains the direct and effective cooling efficiency for the fixed scroll blades, and has a negative thermal effect on the orbiting scroll blades and other compression mechanisms as a whole. This has the effect of reducing power consumption and improving reliability. Further , according to the present invention , a pair of injection holes are provided corresponding to the pair of compression spaces, respectively, and the injection hole is formed at a crank angle of 4 degrees from the completion of suction of each compression space.
Since the liquid refrigerant is set to be guided to each compression space at a position rotated by 0 ° or more, there is an effect that the injection of the liquid refrigerant into the compression space does not decrease the refrigerating capacity and improves the injection efficiency.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a vertical sectional view of a scroll compressor according to one embodiment of the present invention, taken along line AOA of FIG. FIG. 2 shows a compression mechanism of the compressor of the embodiment.
FIG. 2 is a cross-sectional plan view along the line BB in FIG. 1. FIG. 3 is a view for sequentially explaining a compression action of the embodiment. FIG. 4 is a configuration diagram of a refrigeration cycle including a scroll compressor according to the embodiment. [Description of Signs] 12 ... fixed scroll wing, 12a ... end plate part (of fixed scroll wing), 12b ... wing part (of fixed scroll wing), 1
1 ... orbiting scroll wing, 11a ... end plate (of orbiting scroll wing), 11b ... wing (of orbiting scroll wing), S
… Compression space, B… condenser, C… decompression device, D… evaporator,
R: Refrigeration cycle circuit, I: Injection circuit, 1
7: Refrigerant sump, 20: Injection hole.

Claims (1)

(1) The spiral wings of the fixed scroll wing and the spiral wings of the orbiting scroll wing are meshed with each other, and these wings and the end plate of each scroll wing are engaged with each other. Forming a pair of compression spaces, and orbiting the orbiting scroll blades to simultaneously suck in the refrigerant gas from the peripheral end side of each compression space and compress by reducing the volume accompanying the movement to the center of each compression space. A low-pressure type scroll compressor that discharges from a discharge port provided in the compressor section; a scroll compressor that is sequentially connected via a refrigerant pipe from a compressor discharge section to a suction section; A refrigeration cycle circuit comprising a condenser, a decompression device, and an evaporator; one end is connected between the condenser and the decompression device, and the other end is connected to the scroll compressor, and is derived from the condenser. Part of the high-pressure liquid refrigerant An injection circuit leading to a roll-type compressor; an arc-shaped groove provided on an outer peripheral portion of a discharge port on a rear surface of a head portion of a fixed scroll blade in the scroll compressor; and the concave groove mounted on a rear surface of the head portion. A refrigerant sump for collecting a liquid refrigerant guided from the injection circuit through a guide port radially penetrating an outer peripheral wall forming the concave groove, the fixing plate comprising: provided volute, communicates the coolant reservoir portion and the compression space, clan from the time of suction completion of each compression space
Opening position in the compression space when rotated by more than 40 °
And a fixed scroll so as to cover the pair of injection holes and the discharge port and the partition plate.
Fixed to the end plate of the wing to form a closed discharge space
A refrigerating apparatus equipped with a scroll compressor, comprising: a valve cover, and a discharge refrigerant pipe opened to the discharge closed space .