JP4523895B2 - Hermetic compressor and refrigeration cycle apparatus - Google Patents

Description

  The present invention relates to a rotary hermetic compressor constituting a refrigeration cycle of an air conditioner, for example, and a refrigeration cycle apparatus including the hermetic compressor.

In recent years, a two-cylinder rotary hermetic compressor including two sets of cylinders constituting a compression mechanism is being standardized. In such a compressor, if a cylinder chamber that always performs a compression action and a cylinder chamber that can be switched to a non-compression operation that is a compression operation and an operation stop according to the magnitude of the load, the specifications can be expanded. To be advantageous.
In view of this, the present applicant, in [Patent Document 1], has two cylinder chambers, and pressurizes one of the cylinder chambers to forcibly hold the vane (blade) away from the roller, thereby compressing the cylinder chamber. It came to provide the closed type compressor provided with the means to interrupt, and the refrigerating-cycle apparatus provided with this compressor.
Specifically, compressed refrigerant gas is discharged into a sealed case to increase the pressure in the case, each cylinder chamber is provided with a vane, one vane is pressed and urged by a spring member, and the other vane places the vane chamber in the case. In addition to the pressure, a high pressure or a low pressure is introduced into the cylinder chamber provided with the vane, and the vane is pressed or not pressed according to the pressure difference from the vane chamber.
JP 2004-301114 A

If such a configuration is adopted, the pressure biasing structure for the vane can be simplified, and the change from the large capacity operation to the low capacity operation can be facilitated. A circuit for introducing high voltage must be provided. That is, one end of the high-pressure introduction pipe is connected to the high-pressure side, and the other end is connected to a midway part of the suction pipe communicating with the cylinder chamber.
Therefore, the pipe length of the high-pressure introduction pipe is increased to some extent, and a plurality of valves such as an on-off valve and a check valve are provided in the middle of the high-pressure introduction pipe, resulting in pressure loss in the high-pressure introduction pipe. It is inevitable to do. For this reason, the pressure in the cylinder chamber is not sufficiently high during low-capacity operation, and a differential pressure may occur between the front end and the rear end of the blade.
At this time, the pressing and urging operation with respect to the blade becomes unstable, and the blade cannot be reliably pressed against the vane chamber. And since the eccentric roller always rotates eccentrically in the cylinder chamber, there is a possibility that the eccentric roller repeatedly collides with the tip of the blade, resulting in the occurrence of collision noise.

  The present invention has been made on the basis of the above circumstances. The purpose of the present invention is to forcibly open a discharge valve in a specific compression mechanism section and guide the high-pressure refrigerant in the sealed case to the cylinder chamber. A hermetic compressor that makes it possible to switch from a capability driving state to a low-capacity driving state, performs stable low-capacity operation, and prevents silent noise such as collision noise and quiet operation, and this hermetic compression An object of the present invention is to provide a refrigeration cycle apparatus equipped with a machine to improve the refrigeration cycle performance.

In order to satisfy the above object, the hermetic compressor of the present invention houses an electric motor part and a plurality of compression mechanism parts in a hermetic case, and at least one of the compression mechanism parts has an eccentric rotation roller. Cylinder having a cylinder chamber that can be freely accommodated, a blade that is pressed and urged so that the tip abuts against the circumferential surface of the roller, and bisects the cylinder chamber along the rotation direction of the roller, and the refrigerant compressed in the cylinder chamber is cylinder A discharge valve that discharges from the cylinder, and high pressure refrigerant introduction means for guiding the high pressure refrigerant into the cylinder chamber and separating the blade from the roller,
High-capacity operation in which compression operation is performed in all the compression mechanism units according to the magnitude of the load, and low-capacity operation in which high-pressure refrigerant introduction means acts to separate the rollers of a specific compression mechanism unit from the blade and perform non-compression Can be switched to
The high-pressure refrigerant introduction means separates the discharge valve from the valve seat, and a pressure introduction mechanism that introduces a low pressure to the cylinder chamber surface side of the discharge valve during large capacity operation and directs a high pressure to the cylinder chamber surface side of the discharge valve during low capacity operation An auxiliary elastic mechanism that urges an elastic force in the direction, and a discharge valve support mechanism that supports the discharge valve and opens and closes the discharge port according to the differential pressure on both sides of the discharge valve.
In order to satisfy the above object, a refrigeration cycle apparatus of the present invention includes the above-described hermetic compressor, a condenser, an expansion device, and an evaporator to constitute a refrigeration cycle circuit.

  In order to satisfy the above object, a refrigeration cycle apparatus of the present invention includes the above-described hermetic compressor, a condenser, an expansion device, and an evaporator, and constitutes a refrigeration cycle circuit.

  According to the present invention, the compression operation with variable capacity according to the magnitude of the load is performed, the stable operation state is maintained, the occurrence of abnormal noise such as a collision sound is prevented, the reliability is improved, and the refrigeration cycle performance There are effects such as improvement of

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a configuration diagram of a sectional structure of a rotary type hermetic compressor R and a refrigeration cycle circuit K of a refrigeration cycle apparatus including the hermetic compressor R. (In order to avoid complications in the drawings, some components are not labeled. The same applies hereinafter.)
First, the hermetic compressor R will be described. 1 is a hermetic case, and a lower part in the hermetic case 1 is provided with a first compression mechanism part 2A and a second compression mechanism part 2B, which will be described later. Is provided with an electric motor section 3. The electric motor unit 3 and the first and second compression mechanism units 2 </ b> A and 2 </ b> B are connected via the rotating shaft 4.

The electric motor unit 3 includes a stator 5 that is fixed to the inner surface of the sealed case 1 and a rotor 6 that is disposed inside the stator 5 with a predetermined gap and is fitted to the rotating shaft 4. The
Each of the first and second compression mechanism portions 2A and 2B includes a first cylinder 8A and a second cylinder 8B, which are respectively disposed above and below the rotary shaft 4 with an intermediate partition plate 7 interposed therebetween. ing. The first and second cylinders 8A and 8B are set to have different outer shape dimensions and the same inner diameter dimension.

A main bearing 9 is superimposed on the upper surface of the first cylinder 8A, and is fixed to the first cylinder 8A via a mounting bolt together with the valve cover a. The auxiliary bearing 10 is superimposed on the lower surface portion of the second cylinder 8B, and is fixed to the second cylinder 8B together with the valve cover b via a mounting bolt.
A flange portion of the main bearing 9 is provided with a first discharge valve mechanism Ta covered with the valve cover a. A second discharge valve mechanism Tb covered with the valve cover b is also provided on the flange portion of the auxiliary bearing 10. Details of the first discharge valve mechanism Ta and the second discharge valve mechanism Tb will be described later.

The outer diameter of the intermediate partition plate 7 and the auxiliary bearing 10 is somewhat larger than the inner diameter of the second cylinder 8B, and the inner diameter position of the second cylinder 8B is deviated from the center of the cylinder. Therefore, a part of the outer periphery of the second cylinder 8 </ b> B protrudes in the radial direction from the outer diameters of the intermediate partition plate 7 and the auxiliary bearing 10.
On the other hand, the rotating shaft 4 is pivotally supported by the main bearing 9 and the auxiliary bearing 10 at the midway portion and the lower end portion. Further, the rotary shaft 4 penetrates through the cylinders 8A and 8B, and integrally includes two eccentric portions formed with a phase difference of about 180 °. Each eccentric part has the same diameter as each other, and is assembled so as to be located in each cylinder 8A, 8B inner diameter part. Eccentric rollers 12a and 12b having the same diameter are fitted on the peripheral surface of each eccentric portion.

The first cylinder 8A and the second cylinder 8B are divided into upper and lower surfaces by the intermediate partition plate 7, the main bearing 9 and the auxiliary bearing 10, and the first and second cylinder chambers 14a and 14b are respectively provided inside. It is formed. The first and second cylinder chambers 14a and 14b are formed to have the same diameter and height, and the eccentric rollers 12a and 12b are accommodated so as to be rotatable eccentrically.
The height of each eccentric roller 12a, 12b is formed substantially the same as the height of the first and second cylinder chambers 14a, 14b. Accordingly, the eccentric rollers 12a and 12b have a phase difference of 180 ° from each other. However, the eccentric rollers 12a and 12b are rotated in the first and second cylinder chambers 14a and 14b so that they are the same in the first and second cylinder chambers 14a and 14b. Excluded volume is set.

FIG. 2 is an exploded perspective view showing a part of each of the first compression mechanism portion 2A and the second compression mechanism portion 2B.
The first cylinder 8A and the second cylinder 8B are provided with blade chambers 15a and 15b communicating with the first and second cylinder chambers 14a and 14b. The blade chambers 15a and 15b accommodate the tip portions of the blades 16a and 16b so as to protrude and retract with respect to the first and second cylinder chambers 14a and 14b.
The blade chambers 15a and 15b are integrally connected to the blade housing grooves 17a and 17b in which both side surfaces of the blades 16a and 16b are slidably movable and end portions of the blade housing grooves 17a and 17b. It consists of vertical hole portions 18a and 18b in which the rear end portions are accommodated.
In particular, the first cylinder 8A is provided with a lateral hole 20 that communicates the outer peripheral surface with the blade chamber 15a, and accommodates the spring member 21 therein. The spring member 21 is interposed between the rear end surface of the blade 16a and the inner peripheral surface of the sealed case 1, and applies an elastic force (back pressure) to the blade 16a so that the tip of the blade is a peripheral surface of the eccentric roller 12a. It is a compression spring which makes it contact elastically.

The blade chamber 15b on the second cylinder 8B side contains no members other than the blade 16b. However, as will be described later, the setting environment of the blade chamber 15b and the high-pressure refrigerant introduction mechanism (high-pressure refrigerant introduction means) P Depending on the action, the tip of the blade 16b is brought into contact with the eccentric roller 12b or not.
The tip portions of the blades 16a and 16b are each formed in a semicircular shape in plan view, and can make line contact with the circumferential surfaces of the circular eccentric rollers 12a and 12b in plan view regardless of the rotation angle of the eccentric roller. .
When the eccentric rollers 12a and 12b rotate eccentrically along the inner peripheral walls of the first and second cylinder chambers 14a and 14b, the blades 16a and 16b reciprocate along the blade housing grooves 17a and 17b, The second cylinder chambers 14a and 14b are partitioned into a suction chamber and a compression chamber. The rear end portions of the blades 16a and 16b can be moved forward and backward from the vertical hole portions 18a and 18b.

A part of the outer shape of the second cylinder 8B is exposed in the sealed case 1 because of the relationship between the outer shape of the second cylinder 8B and the outer dimensions of the intermediate partition plate 7 and the auxiliary bearing 10. The exposed portion in the sealed case 1 is designed to correspond to the blade chamber 15b. Therefore, the blade chamber 15b and the rear end of the blade 16b directly receive the pressure in the case.
In particular, since the second cylinder 8B and the blade chamber 15b are structures, there is no effect even if they are subjected to pressure in the case, but the blade 16b is slidably accommodated in the blade chamber 15b and the rear end portion is Since it is located in the vertical hole portion 18b of the blade chamber 15b, it receives the pressure in the case directly.

Furthermore, the tip of the blade 16b faces the second cylinder chamber 14b, and the blade tip receives the pressure in the second cylinder chamber 14b. Eventually, the blade 16b is configured to move in the direction from the higher pressure to the lower pressure according to the magnitude (differential pressure) of the mutual pressure received by the front end and the rear end.
A holding mechanism 22 is provided at a position adjacent to the vertical hole portion 18b of the blade chamber 15b in the second cylinder 8B. The holding mechanism 22 attracts the rear end portion of the blade 16b, and urges the blade front end portion in a direction to separate the blade 16b from the eccentric roller 12b. However, the holding mechanism 22 has a pressure difference between the pressure applied to the second cylinder chamber 14b where the tip of the blade 16b is located and the pressure inside the sealed case 1 applied to the blade chamber 15b where the rear end of the blade 16b is located. to be influenced.

As the holding mechanism 22, a permanent magnet is used for the blade 16b formed of a magnetic material. Alternatively, an electromagnet may be provided instead of the permanent magnet, and magnetic attraction may be performed as necessary. Alternatively, one end portion of the tension spring, which is an elastic body, may be hooked on the rear end portion of the blade 16b, and may always be tensioned and biased with a predetermined elastic force.
Each cylinder 8A, 8B is provided with a mounting hole through which the mounting bolt is inserted or screwed, or a screw hole, and only the first cylinder 8A has an arc-shaped gas passage hole 23. .
Next, the first discharge valve mechanism Ta provided at the flange portion of the main bearing 9 and the second discharge valve mechanism Tb provided at the flange portion of the auxiliary bearing 10 will be described.
In the first discharge valve mechanism Ta, a discharge port communicating with the first cylinder chamber 14a is opened in the flange portion of the main bearing 9, and a valve seat is integrally provided along the periphery of the discharge port of the flange portion. A discharge valve is attached to the valve seat so that the discharge port can be freely opened and closed. The discharge valve is a thin leaf-type reed valve whose one end is attached and fixed to the flange portion via a fixture and the other end covers the discharge port.

In other words, when the inside of the first cylinder chamber 14a becomes a predetermined pressure or higher, the discharge valve is elastically deformed so as to open the discharge port in response to the pressure. When the pressure becomes lower than the predetermined pressure, the elastic return force acts on the discharge valve again to return to the original flat plate shape, and the discharge port is closed.
Here, the high-pressure refrigerant introduction mechanism P includes an electromagnet mechanism as the first embodiment, and the electromagnet mechanism P is provided for the second discharge valve mechanism Tb.
FIG. 3A is a schematic configuration diagram of the second discharge valve mechanism Tb and the electromagnet mechanism P, and FIG. 3B is a plan view of the discharge valve 35 provided in the second discharge valve mechanism Tb.

A concave portion c is provided in the flange portion 10a of the auxiliary bearing 10, and a discharge port 36 communicating with the second cylinder chamber 14b is opened here. A valve seat d having a semicircular cross section is integrally provided along the periphery of the discharge port 36 on the concave side.
A discharge valve 35 is attached to the recess c via a support mechanism. The discharge valve 35 is made of a magnetic material and is a free valve made of an extremely thin plate. For example, it is formed in a circular shape with respect to the circular discharge port 36 in plan view and is detachably supported by the support mechanism without being detached from the valve seat d. In this way, the second discharge valve mechanism Tb is configured.

The electromagnet mechanism P is disposed to face the discharge valve 35 supported by the support mechanism at a predetermined interval. The electromagnet mechanism P includes a valve presser 37 and an electromagnet 38 that attaches and supports the valve presser 37. The valve presser 37 is a rigid body having a certain thickness, and has a hollow portion formed in the shaft center, and has an annular shape (so-called donut shape) in plan view. The upper end portion of the rod-shaped electromagnet 38 is press-fitted into the hollow portion of the valve presser 23.
The outer diameter of the valve retainer 37 is larger than the diameter of the discharge valve 35, and the diameter of the electromagnet 38, which is the hollow dimension of the valve retainer 37, is smaller than the diameter of the discharge valve 35. . The upper end surface of the electromagnet 38 is slightly lower than the upper surface of the valve presser 37, and a slight step is formed. A winding 39 is provided on a portion of the electromagnet 38 protruding from the lower surface of the valve presser 37.

As shown in FIG. 1 again, the winding 39 is electrically connected to a power terminal N for an electromagnet provided at the lower portion of the side wall of the sealed case 1. The electromagnet mechanism P is configured as described above.
The rotary hermetic compressor R is incorporated in the refrigeration cycle circuit K of the refrigeration cycle apparatus. That is, a discharge pipe 25 is connected to the upper end portion of the sealed case 1, and an accumulator 29 is sequentially provided in the discharge pipe 25 via a condenser 26, an expansion mechanism (expansion device) 27, and an evaporator 28. It is done.
Two suction pipes 30a and 30b are extended from the accumulator 29, and the first suction pipe 30a passes through the sealed case 1 and is connected to a suction hole provided in the first cylinder 8A. Therefore, the first cylinder chamber 14a and the accumulator 29 are communicated with each other via the first suction pipe 30a.

The second suction pipe 30b passes through the sealed case 1 and is connected to a suction hole provided in the second cylinder 8B. Accordingly, the twelfth cylinder chamber 14b and the accumulator 29 are communicated with each other via the second suction pipe 30b. A check valve 31 is provided in the middle of the suction pipe 30b.
Next, the operation of the refrigeration cycle apparatus provided with the above-described hermetic compressor R will be described. As will be described later, the hermetic compressor R can be switched between a large capacity operation (twin operation) and a low capacity operation (single operation).
First, from the description of high-capacity operation, the control unit sends an operation start signal to the motor unit 3, but as shown in FIG. 3 (A), the electromagnet mechanism P disposed opposite to the second discharge valve mechanism Tb. No excitation signal is sent to the electromagnet 38. Therefore, the discharge valve 35 in the second discharge valve mechanism Tb enables a normal opening / closing operation.

The rotary shaft 4 is rotationally driven, and the first compression mechanism 2A and the second compression mechanism 2B act simultaneously. The eccentric rollers 12a and 12b rotate eccentrically in the first and second cylinder chambers 14a and 14b, respectively. In the first compression mechanism 2A, the blade 16a is always elastically pressed and biased by the spring member 21, and the tip of the blade 16a is slidably contacted with the circumferential surface of the eccentric roller 12a to suck the first cylinder chamber 14a. Divide into chamber and compression chamber.
The position of the inner peripheral surface rolling contact of the first cylinder chamber 14a of the eccentric roller 12a coincides with the blade housing groove 17a, and the space capacity of the cylinder chamber 14a is maximized when the blade 16a is retracted most. The low-pressure refrigerant gas led from the accumulator 29 through the first suction pipe 30a is sucked into the first cylinder chamber 14a and is filled.

In the first cylinder chamber 14a, as the eccentric roller 12a rotates eccentrically, the rolling contact position of the eccentric roller 12a with respect to the inner peripheral surface of the cylinder chamber 14a moves, and the volume of the compression chamber partitioned by the blade 16a decreases. That is, the gas previously introduced into the cylinder chamber 14a is gradually compressed.
The rotary shaft 4 continues to rotate, the capacity of the compression chamber in the first cylinder chamber 14a further decreases, the refrigerant gas is compressed, and the discharge valve is opened when the pressure rises to a predetermined pressure. The high-pressure refrigerant gas is discharged and filled into the sealed case 1 through the valve cover a. And it is led to the refrigeration cycle circuit K from the discharge pipe 25 connected to the upper part of the sealed case 1.

The high-pressure refrigerant discharged from the discharge pipe 25 is condensed and liquefied by the condenser 26, adiabatic expansion is performed by the expansion mechanism 27, and latent heat of evaporation is removed from the heat exchange air by the evaporator 28 to perform a refrigeration action. The evaporated refrigerant is guided to the accumulator 29 and separated into gas and liquid, and is sucked into the first and second compression mechanisms 2A and 2B of the compressor R from the first and second suction pipes 30a and 30b. It is.
As described above, the refrigerant guided from the accumulator 29 to the first compression mechanism portion 2A via the first suction pipe 30a is compressed and discharged into the sealed case 1. Further, the second cylinder chamber 14b is brought into a suction pressure (low pressure) atmosphere by the low-pressure refrigerant guided from the second suction pipe 30b to the second cylinder chamber 14b. On the other hand, the high-pressure refrigerant gas is filled in the sealed case 1, and the blade chamber 15b constituting the second compression mechanism portion 2B is exposed in the sealed case 1 to form a discharge pressure (high pressure) atmosphere.

The tip of the blade 16b has a low pressure condition, the rear end has a high pressure condition, and a differential pressure exists at the front and rear ends. Under the influence of this differential pressure, the tip of the blade 16b is pressed and urged so as to be in sliding contact with the eccentric roller 12b. The urging force of the holding mechanism 22 is smaller than the differential pressure between the suction pressure of the second cylinder chamber 14b and the pressure inside the sealed case 1 of the blade chamber 15b. Therefore, there is no influence of the holding mechanism 22 on the blade 16b.
In this way, exactly the same compression action is performed in the second cylinder chamber 14b as the blade 16a on the first cylinder chamber 14a side is pressed and urged by the spring member 21 to perform the compression action. Eventually, in the hermetic compressor R, a large capacity operation is performed in which the compression action is performed by both the first compression mechanism 2A and the second compression mechanism 2B.

Next, low-performance driving will be described.
When the low-capacity operation start signal enters the control unit, as shown in FIG. 4, the control unit issues an excitation signal to the electromagnet 38 of the electromagnet mechanism P disposed opposite to the second discharge valve mechanism Tb. Then, an operation start signal is sent to the motor unit 3.
When the electromagnet 38 is excited, a magnetic force is generated with respect to the discharge valve 35, and the discharge valve 35 is magnetically attracted and fixed to the upper end surface of the valve presser 37. The discharge valve 35 is forcibly separated from the valve seat d, and the discharge port 36 is opened. Since the upper end surface of the electromagnet 38 is slightly retracted from the upper surface of the valve retainer 37 to form a step, the discharge valve 35 is placed on the valve retainer 37 and is not directly magnetically attracted to the electromagnet 38.

As described above, the first compression mechanism portion 2A performs a normal compression action, the high pressure gas discharged into the sealed case 1 is filled, and the inside of the sealed case 1 is at a high pressure. Further, in the second compression mechanism portion 2A, the discharge port 36 is opened, and the second cylinder chamber 14b and the inside of the sealed case 1 are in communication with each other. Therefore, as indicated by the broken line arrow in the figure, a part of the high-pressure refrigerant filling the sealed case 1 is introduced into the second cylinder chamber 14b through the discharge port 36, and the second cylinder chamber 14b is in a high-pressure atmosphere. It becomes.
On the other hand, the blade chamber 15b provided in the second cylinder 8B remains unchanged under the same high pressure as that in the sealed case 1. Therefore, the blade 16b provided in the second cylinder chamber 14b is affected by the high pressure at the front end portion and the rear end portion, and there is no differential pressure.

The blade 16b is pushed away by the first rotation of the eccentric roller 12b, and the tip of the blade 16b is separated from the outer peripheral surface of the eccentric roller 12b as it is. Then, the rear end portion of the blade 16 b comes into contact with the holding mechanism 22 and is magnetically attracted and held by the holding mechanism 22. Since the tip of the blade 16b is kept away from the circumferential surface of the eccentric roller 12b, the eccentric roller 12b rotates idly.
Eventually, the compression action in the second cylinder chamber 14b is not performed, and the second compression mechanism portion 2B enters a non-compression operation state (also referred to as a cylinder resting state). Only the compression action in the first compression mechanism 2A is effective, and the low-capacity operation that halves the large-capacity operation described above is performed.
At this time, the eccentric roller 12b does not repeatedly collide with the blade 16b, and no collision noise is generated. When the second cylinder chamber 14 b becomes a high-pressure atmosphere, the high-pressure refrigerant is guided to the second suction pipe 30 b communicating with the cylinder chamber 14 b and tends to flow back into the accumulator 29.

However, since the check valve 31 is provided in the second suction pipe 30b, the backflow to the accumulator 29 is prevented. The inside of the second cylinder chamber 14b is at a high pressure, and no leakage of compressed gas from the sealed case 1 into the second cylinder chamber 14b occurs, and no loss is caused thereby. Therefore, low-capacity operation is possible without a decrease in compression efficiency.
Since the electromagnet mechanism P that is the high-pressure refrigerant introduction mechanism is provided, the electromagnet mechanism P immediately holds the discharge valve 35 magnetically and opens the discharge port 36 when a low-capacity operation start signal is sent. The high-pressure refrigerant that fills the sealed case 1 is guided into the second cylinder chamber 14b in a very short time and is increased in pressure. Since there is no pressure loss, the high pressure condition of the second cylinder chamber 14b is stabilized, and the blade 16b is pressed and urged. A reliable and reliable low-performance operation can be maintained, and no abnormal noise such as collision noise is generated.

Next, the hermetic compressor R having the high-pressure refrigerant introduction mechanism Pa and the refrigeration cycle apparatus according to the second embodiment will be described with reference to FIG. (In addition, about the same component as the above-mentioned embodiment, the same number is attached | subjected and new description is abbreviate | omitted).
FIG. 5 is a sectional view of the hermetic compressor R and a configuration diagram of the refrigeration cycle circuit K, FIG. 6 is an exploded sectional view of the high-pressure refrigerant introduction mechanism Pa of the second embodiment, and FIG. FIG. 8 is a cross-sectional view of the high-pressure refrigerant introduction mechanism Pa during high-capacity operation, and FIG. 9 is a cross-sectional view of the high-pressure refrigerant introduction mechanism Pa during low-capacity operation.
The high-pressure refrigerant introduction mechanism Pa includes a pressure introduction mechanism 40, an auxiliary elastic mechanism 50, and a discharge valve support mechanism 55.

As shown in FIG. 5, the pressure introduction mechanism 40 includes a pressure introduction pipe 41 branched from the refrigeration cycle circuit K and connected to the second cylinder 8B. That is, one end of the pressure introducing pipe 41 is connected to the discharge pipe 25 connected to the sealed case 1 of the hermetic compressor R. Instead of the discharge pipe 25, the discharge pipe 25 may be directly connected to the upper end portion of the sealed case 1 that does not face the electric motor unit 3 housed in the sealed case 1.
Further, one end portion of the pressure introducing pipe 41 is connected to a low pressure pipe 25 </ b> A that communicates the evaporator 28 and the accumulator 29. Instead of the low pressure pipe 25A, it is connected to the first suction pipe 30a that communicates the accumulator 29 and the first cylinder 8A or the second suction pipe 30b that communicates the accumulator 29 and the second cylinder 8B. It may be.

The two pressure introduction pipes 41 each having an end connected to each of the above are connected to two ports of a three-way switching valve 42 provided outside the sealed case 1. The pressure introducing pipe 41 connected to the remaining ports in the three-way switching valve 42 passes through the sealed case 1 and is connected to the side surface portion of the second cylinder 8B.
As shown in FIG. 6, a pressure introduction port 43 is provided along the plate thickness direction from the side surface portion of the second cylinder 8B, and the tip of the pressure introduction port 43 is provided on the lower surface portion of the second cylinder 8B. It communicates with the spring accommodating recess 44. The spring accommodating recess 44 is a circular recess provided in the lower surface of the second cylinder 8B, and has a predetermined distance from the hole forming the second cylinder chamber 14b, and the second cylinder 8B. And the vicinity of the discharge port 45 provided across the flange portion of the auxiliary bearing 10. Of course, a valve seat is provided along the periphery of the opening of the discharge port 45.

In the flange portion of the auxiliary bearing 10, a communication hole 46 is provided so as to face the spring housing recess 44, and a guide recess 47 is provided across the communication hole 46 and the discharge port 45. The guide concave portion 47 is provided on the lower surface of the flange portion, and as shown in FIG. 7, both ends have a circular shape, and the circular portions at both ends communicate with each other by a straight concave portion. An O-ring 48, which is a sealing material, is attached to the periphery of the communication hole 46 so as to face the guide recess 47.
A spring 50 constituting the auxiliary elastic mechanism is inserted into the pressure introducing mechanism 40 from the spring accommodating recess 44 to the communication hole 46. The spring 50 is wound in a coil shape, and its upper end is slightly smaller than the diameter of the spring accommodating recess 44 and is fitted into the spring accommodating recess 44. The lower end portion of the spring 50 has a diameter supported by the discharge valve support mechanism 55, and is formed to have a small diameter from the upper end portion to the lower end portion.

The discharge valve support mechanism 55 has a guide 56 provided on the flange portion of the auxiliary bearing 10. The guide 56 has a structure similar to that obtained when the plate piece is bent into a substantially U shape when viewed from the front, and both upper end portions are the lower surface of the flange portion of the auxiliary bearing 10 and the straight portion of the guide recess 47. Installed and fixed at the straddling position. A hole e is provided in a surface portion parallel to the flange portion forming the bottom side of the guide 56, and the slider 57 is inserted therein.
The slider 57 has a screw at the top and a diameter smaller than that of the hole e. Therefore, the slider 57 can be inserted into the hole e. A presser nut 58 is screwed in close contact with the head of the slider 57, the discharge valve 60 and the valve presser 61 are inserted, and a fixing nut 62 is screwed. Further, a stopper 63 is fixed to the slider 57 with a predetermined distance from the fixing nut 62.

The discharge valve 60 and the valve presser 61 are sandwiched between a presser nut 58 and a fixed nut 62, and are attached and fixed to the head of the slider 57. The stopper 63 does not contribute to mounting and fixing the discharge valve 60 and the valve presser 61 at all.
The discharge valve 60 has a portion protruding from the portion clamped and fixed by the presser nut 58 and the fixing nut 62 toward the discharge port 45, and completely closes the communication hole 46 and the discharge port 45 as a whole. It has a sufficient shape area. Moreover, it is a reed valve that is thin and extremely lightweight and can be easily elastically deformed.
The valve presser 61 is a plate body having a predetermined thickness, and protrudes downward toward the discharge port 45 side, a straight portion sandwiched and fixed between the presser nut 58 and the fixing nut 62 together with the discharge valve 60. It consists of a curved part.

The discharge valve support mechanism 55 configured as described above is inserted into the hole e of the guide 56 from the lower end of the slider 57, and a stopper 63 provided on the slider 57 is placed on the guide 56, and the lower end of the slider 57 is Projects downward from the stopper 63. The discharge valve 60 and the valve presser 61 provided on the slider 57 are positioned in the guide recess 47 provided on the auxiliary bearing 10 together with the presser nut 58 and the fixing nut 62. The spring 50 is inserted into the spring accommodating recess 44, and the lower end of the spring 50 is placed on the upper surface of the presser nut 58 of the slider 57.
The high-pressure refrigerant introduction mechanism Pa switches and controls the three-way switching valve 42 so that a part of the low-pressure refrigerant exchanged with the evaporator 28 during the large capacity operation is led to the second cylinder 8B through the pressure introduction pipe 41. During operation, the three-way switching valve 42 is controlled to be switched so that a part of the high-pressure refrigerant discharged from the sealed case 1 is guided to the second cylinder 8B through the pressure introduction pipe 41.

FIG. 8 shows a state during high-capacity driving. That is, the low-pressure refrigerant Ps is guided from the pressure introduction pipe 41 to the upper surface side that is one surface side of the discharge valve 60 from the spring accommodating recess 44 and the communication hole 46 through the pressure introduction port 43 provided in the second cylinder 8B. On the other hand, the inside of the sealed case 1 is in a high pressure atmosphere, and a high pressure is applied to the lower surface side which is the other surface side of the valve presser 61 and the discharge valve 60.
Therefore, the lower surface side of the discharge valve 60 is high pressure, the upper surface side is low pressure, and a differential pressure is generated between both surfaces. The discharge valve 60 and the discharge valve support mechanism 55 are extremely light overall, and a spring 50 is interposed between the presser nut 58 of the slider 57 and the spring accommodating recess 44. Even if the weight and the elastic force of the spring 50 are added, a sufficient differential pressure still exists.

Therefore, the discharge valve support mechanism 55 is entirely pushed up, the stopper 63 is separated from the guide 56, and the discharge valve 60 is pressed against the upper surface of the guide recess 47. The communication hole 46 is closed by the discharge valve 60 and the discharge valve 60 is in close contact with the O-ring 48 provided around the communication hole 46, so that the communication hole 46 is completely closed. The discharge port 45 closes the discharge port 45 so as to be freely opened and closed.
That is, the normal compression action is performed in the second cylinder chamber 14b, and the discharge valve 60 opens the discharge port 45 when the pressure in the compression chamber divided by the blade 16b exceeds a predetermined pressure, otherwise The discharge port 45 is closed. The large capacity operation in which the compression action is performed in the second cylinder chamber 14b together with the first cylinder chamber 14a.

FIG. 9 shows a state during low-performance driving. The high-pressure refrigerant Pd is guided from the pressure introduction pipe 41 through the pressure introduction port 43 to the upper surface side of the discharge valve 60 from the spring accommodating recess 44 and the communication hole 46. On the other hand, the inside of the sealed case 1 is in a high pressure atmosphere, and a high pressure is applied to the lower surfaces of the valve presser 61 and the discharge valve 60.
Therefore, although the upper and lower surfaces of the discharge valve 60 are at high pressure and no differential pressure is generated between both surfaces, the elastic force F of the spring 50 interposed between the slider presser nut 58 and the spring accommodating recess 44 is the pressure on both surfaces of the discharge valve 60. The balance is lost and the discharge valve support mechanism 55 is pressed downward. That is, the spring 50 is an auxiliary elastic mechanism that supplementarily applies an elastic force in the direction of separating the discharge valve 60 from the valve seat.

The stopper 63 of the discharge valve support mechanism 55 is placed on the guide 56, and the discharge valve 60 is separated from the upper surface of the guide recess 47 and is separated from the valve seat to open the discharge port 45. This state is maintained while the high pressure is led from the pressure introducing pipe 41, and the high pressure refrigerant in the sealed case 1 is led to the second cylinder chamber 14b via the discharge port 45.
The second cylinder chamber 14b has the same high pressure atmosphere as the blade chamber 15b provided in the second cylinder 8B, and no differential pressure is generated between the front end portion and the rear end portion of the blade 16b. The blade 16b is pushed away by the first rotation of the eccentric roller 12b, and the tip of the blade 16b is separated from the outer peripheral surface of the eccentric roller 12b as it is.
Eventually, the compression action in the second cylinder chamber 14b is not performed, and the second compression mechanism portion 2B enters a non-compression operation state (also referred to as a cylinder resting state). Only the compression action in the first compression mechanism 2A is effective, and the low-capacity operation that halves the large-capacity operation described above is performed.

Since such a high-pressure refrigerant introduction mechanism Pa is provided, the discharge valve 60 immediately forcibly holds the discharge port 45 open when a low-performance operation start signal is sent. The high-pressure refrigerant that fills the sealed case 1 is guided into the second cylinder chamber 14b in a very short time and is increased in pressure. Since there is no pressure loss, the high pressure condition of the second cylinder chamber 14b is stabilized, and the blade 16b is pressed and urged. A reliable and reliable low-performance operation can be maintained, and no abnormal noise such as collision noise is generated.
It should be noted that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying constituent elements without departing from the scope in the implementation stage, and a plurality of components disclosed in the above-described embodiment. Various inventions can be formed by appropriately combining the components.

The longitudinal cross-sectional view and refrigeration cycle block diagram of a hermetic compressor provided with the high-pressure refrigerant introduction mechanism concerning a 1st embodiment in the present invention. The perspective view which decomposed | disassembled each part of the 1st compression mechanism part and 2nd compression mechanism part based on the embodiment. The block diagram of the high-pressure refrigerant | coolant introduction mechanism at the time of large capacity driving | operation based on the embodiment, and the top view of a discharge valve. The block diagram of the high pressure refrigerant | coolant introduction mechanism at the time of the low capacity | capacitance driving | operation based on the embodiment. The longitudinal cross-sectional view of the hermetic compressor provided with the high pressure refrigerant introduction mechanism concerning the 2nd embodiment in the present invention, and the refrigeration cycle lineblock diagram. The longitudinal cross-sectional view which decomposed | disassembled some high pressure refrigerant | coolant introduction mechanisms based on the embodiment. The top view of a part of high pressure refrigerant introduction mechanism based on the embodiment. Action | operation explanatory drawing of the high voltage | pressure refrigerant | coolant introduction mechanism at the time of large capacity driving | operation based on the embodiment. Action | operation explanatory drawing of the high pressure refrigerant | coolant introduction mechanism at the time of the low capacity | capacitance driving | operation based on the embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Sealing case, 3 ... Electric motor part, 2A ... 1st compression mechanism part, 2B ... 2nd compression mechanism part, 13a, 13b ... Eccentric roller, 14a ... 1st cylinder chamber, 14b ... 2nd cylinder chamber , 8A ... first cylinder, 8B ... second cylinder, 15a, 15b ... blade, 20, 60 ... discharge valve, d ... valve seat, 36, 45 ... discharge port, P, Pa ... high pressure refrigerant introduction mechanism (high pressure) Refrigerant introduction means), P ... electromagnet mechanism, 40 ... pressure introduction mechanism, 50 ... auxiliary elastic mechanism, 55 ... discharge valve support mechanism, R ... sealed compressor, 26 ... condenser, 27 ... expansion mechanism (expansion device), 28 ... Evaporator, K ... Refrigeration cycle circuit.

Claims (2)

In a hermetic compressor including a hermetically sealed case, an electric motor unit accommodated in the hermetic case, and a plurality of compression mechanism units connected to the electric motor unit,
At least one compression mechanism part of the compression mechanism parts is:
A cylinder having a cylinder chamber in which the roller is eccentrically rotatable, and a cylinder chamber provided in this cylinder, which is pressed and urged to abut the peripheral surface of the roller, bisects the cylinder chamber along the rotation direction of the roller. A blade, a discharge valve that discharges the refrigerant compressed to a predetermined pressure in the cylinder chamber from the cylinder chamber into the sealed case, and high-pressure refrigerant introduction means that guides the high-pressure refrigerant into the cylinder chamber and separates the blade from the roller. ,
High-capacity operation that performs compression operation in all compression mechanism units according to the size of the load, and low-capacity operation that operates the high-pressure refrigerant introduction means to separate the rollers of a specific compression mechanism unit from the blade and perform non-compression And can be switched to
The high-pressure refrigerant introducing means is configured to introduce a low-pressure to the cylinder chamber surface side of the discharge valve during high-capacity operation and to introduce a high pressure to the cylinder chamber surface side of the discharge valve during low-capacity operation; And a discharge valve support mechanism that supports the discharge valve and opens and closes the discharge port in accordance with a differential pressure on both sides of the discharge valve. A hermetic compressor. A refrigeration cycle apparatus comprising the hermetic compressor according to claim 1 , a condenser, an expansion device, and an evaporator to constitute a refrigeration cycle circuit.

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