JP4594301B2 - Hermetic rotary compressor - Google Patents

Description

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

  A general hermetic rotary compressor has a configuration in which an electric motor unit and a compression mechanism unit connected to the electric motor unit are accommodated in a hermetic case, and gas compressed by the compression mechanism unit is once discharged into the hermetic case. It is a high pressure type inside the case.

  In the compression mechanism section, an eccentric roller is accommodated in a cylinder chamber provided in the cylinder. The cylinder is provided with a blade chamber in which the blade is slidably accommodated. The tip edge of the blade is pressed and urged by a compression spring so as to always protrude toward the cylinder chamber and elastically contact the peripheral surface of the eccentric roller. Therefore, the cylinder chamber is divided into a suction chamber and a compression chamber along the rotation direction of the eccentric roller by the blade.

  By the way, in recent years, a two-cylinder hermetic rotary compressor provided with two sets of the compression mechanism section above and below is being standardized. If such a compressor can be provided with a compression mechanism part that always performs a compression action and a compression mechanism part that can be switched between compression and stop if necessary, the specifications are expanded and advantageous.

  For example, Japanese Patent Application Laid-Open No. 1-247786 includes two cylinder chambers, and includes a high-pressure introduction unit that introduces a high pressure into the cylinder chamber while setting the back side of one of the blades to an intermediate pressure as necessary. A technique is disclosed in which the compression action is interrupted by forcibly holding the blade away from the eccentric roller due to a pressure difference between the blade tip side and the back surface side.

  This type of compressor is extremely functionally superior, but in order to constitute a high-pressure introduction means, a high-pressure introduction hole that communicates one cylinder chamber and the inside of the sealed case is provided, and the back side of the blade is set to an intermediate pressure. The refrigeration cycle is provided with a two-stage throttle mechanism, branched from an intermediate portion of the throttle mechanism, communicated with the blade chamber on one side, and provided with a bypass refrigerant pipe having an electromagnetic on-off valve in the middle. It becomes.

  That is, it is necessary to make a hole for making a high-pressure introduction means for the compressor, and the throttle device on the refrigeration cycle must be a two-stage throttle mechanism. Further, the two-stage throttle mechanism, the cylinder chamber, The pipe length becomes long, such as connecting a bypass refrigerant pipe between. Therefore, not only does the structure become complicated and the cost is adversely affected, but also the suction resistance during normal operation may increase and the efficiency may decrease.

  The present invention has been made on the basis of the above circumstances, and the purpose thereof is to provide at least one compression mechanism section for performing a normal operation and a compression operation on the assumption that a plurality of compression mechanism sections are provided. It is intended to provide a compact and high-performance hermetic rotary compressor that can switch between non-compressed operation and shorten the piping length to reduce the cost by simplifying the piping.

In order to satisfy the above object, a hermetic rotary compressor of the present invention accommodates an electric motor unit and a plurality of compression mechanism units in a hermetic case via a rotary shaft, and at least one compression mechanism unit is a blade. The pressure is urged by the pressure difference between the pressure in the sealed case acting on the back of the blade and the pressure in the cylinder chamber acting on the blade tip, and the compression operation is performed by introducing low-pressure refrigerant into the cylinder chamber via the suction hole. High pressure refrigerant is introduced into the cylinder chamber, the pressure inside the sealed case acting on the back of the blade and the pressure of the high pressure refrigerant guided to the cylinder chamber are balanced, and the pressure is balanced at the front and rear ends of the blade, leading edge of the blade to allow switching between non-compression operation is not performed compression operation at a distance from the outer peripheral surface of the eccentric roller, one end in the cylinder chamber of the compression mechanism that enables operation select With an opening for contact opening, it provided a high pressure introduction passage and the other end communicates with the inside of the sealed casing, provided with closing means for opening and closing the high-pressure introduction passage in the middle portion of the high pressure introducing passage.

FIG. 1 is a longitudinal sectional view and a refrigeration cycle configuration diagram of a hermetic rotary compressor according to an embodiment of the present invention. FIG. 2 is a perspective view in which a part of each of the first compression mechanism portion and the second compression mechanism portion is exploded according to the same embodiment. FIG. 3 is a diagram for explaining the operation during normal operation according to the embodiment. FIG. 4 is a diagram for explaining the operation during special operation according to the embodiment. FIG. 5 is a view for explaining the connection position of the high-pressure introduction passage according to the embodiment. FIG. 6 is a view for explaining the connection position of the high-pressure introduction passage according to another embodiment.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a cross-sectional structure of a hermetic rotary compressor R and a refrigeration cycle configuration diagram of a refrigeration apparatus including the hermetic rotary compressor R.

  First, the sealed rotary compressor R will be described. 1 is a sealed case, and a lower portion in the sealed case 1 is provided with a first compression mechanism 2A and a second compression mechanism 2B which will be described later. An electric motor unit 3 is provided at the upper part. 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.

  For example, a brushless DC synchronous motor (which may be an AC motor or a commercial motor) is used for the electric motor unit 3, and a stator 5 fixed to the inner surface of the sealed case 1 and a predetermined gap exist inside the stator 5. And a rotor 6 that is disposed on the rotary shaft 4. The electric motor unit 3 is connected to an inverter 30 that varies the operating frequency, and is electrically connected to a control unit 40 that performs inverter control via the inverter.

  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. The outer diameter of the first cylinder 8A is slightly larger than the inner diameter of the sealed case 1 and is press-fitted into the inner peripheral surface of the sealed case 1 and then positioned and fixed by welding from the outside of the sealed case 1. The

  A main bearing 9 is superimposed on the upper surface portion of the first cylinder 8A, and is fixed to the cylinder 8A via a mounting bolt 10 together with a valve cover a. The auxiliary bearing 11 is superimposed on the lower surface portion of the second cylinder 8B, and is fixed to the second cylinder 8B via the mounting bolt 12 together with the valve cover b.

  The outer diameter dimensions of the intermediate partition plate 7 and the auxiliary bearing 11 are somewhat larger than the inner diameter dimension of the second cylinder 8B, and the inner diameter position of the cylinder 8B is deviated from the center of the cylinder. Therefore, a part of the outer periphery of the second cylinder 8B protrudes in the radial direction from the outer diameters of the intermediate partition plate 7 and the auxiliary bearing 11.

  On the other hand, the rotary shaft 4 is pivotally supported by the main bearing 9 and the sub-bearing 11 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 4a and 4b formed with a phase difference of about 180 °. The eccentric portions 4a and 4b have the same diameter as each other, and are assembled so as to be located in the inner diameter portions of the cylinders 8A and 8B. Eccentric rollers 13a and 13b having the same diameter are fitted to the peripheral surfaces of the eccentric parts 4a and 4b.

  The first cylinder 8A and the second cylinder 8B have upper and lower surfaces defined by the intermediate partition plate 7, the main bearing 9 and the sub-bearing 11, and cylinder chambers 14a and 14b are formed in the respective interiors. The cylinder chambers 14a and 14b are formed to have the same diameter and height, and the eccentric rollers 13a and 13b are accommodated in the cylinder chambers 14a and 14b so as to be eccentrically rotatable.

  The height of each eccentric roller 13a, 13b is formed substantially the same as the height of each cylinder chamber 14a, 14b. Accordingly, the eccentric rollers 13a and 13b have a phase difference of 180 ° from each other, but are set to the same excluded volume in the cylinder chamber by rotating eccentrically in the cylinder chambers 14a and 14b. Each cylinder 8A, 8B is provided with blade chambers 22a, 22b communicating with the cylinder chambers 14a, 14b. Blades 15a and 15b are accommodated in the respective blade chambers 22a and 22b so as to protrude and retract with respect to the cylinder chambers 14a and 14b.

  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 blade chambers 22a and 22b are integrally connected to the blade housing grooves 23a and 23b in which both side surfaces of the blades 15a and 15b are slidably movable and the ends of the blade housing grooves 23a and 23b. It consists of vertical hole parts 24a and 24b in which the rear end part is accommodated. In particular, the first cylinder 8A is provided with a lateral hole 25 that communicates the outer peripheral surface with the blade chamber 22a, and accommodates the spring member 26 therein. The spring member 26 is interposed between the back side end face of the blade 15a and the inner peripheral surface of the sealed case 1, and applies compression force to the blade 15a so that the tip edge contacts the eccentric roller 13a. It is a spring.

  The blade chamber 22b on the second cylinder 8B side contains no members other than the blade 15b. However, as will be described later, the setting environment of the blade chamber 22b and the action of a pressure switching mechanism (means) K described later. Accordingly, the tip edge of the blade 15b is brought into contact with the eccentric roller 13b.

  The leading edges of the blades 15a and 15b are formed in a semicircular shape in plan view, and can make line contact with the circumferential walls of the circular eccentric rollers 13a and 13b in plan view regardless of the rotation angle of the eccentric roller. When the eccentric rollers 13a and 13b rotate eccentrically along the inner peripheral walls of the cylinder chambers 14a and 14b, the blades 15a and 15b reciprocate along the blade housing grooves 23a and 23b, and suck the cylinder chambers 14a and 14b. Partition the chamber and compression chamber. The rear end portions of the blades 15a and 15b can be moved forward and backward from the vertical hole portions 24a and 24b.

  As described above, a part of the outer shape of the second cylinder 8B is exposed in the sealed case 1 from 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 11. To do. The portion exposed to the sealed case 1 is designed to correspond to the blade chamber 22b. Therefore, the blade chamber 22b and the rear end portion of the blade 15b are directly subjected to the pressure in the case.

  In particular, since the second cylinder 8B and the blade chamber 22b are structures, there is no influence even if they are subjected to pressure inside the case, but the blade 15b is slidably accommodated in the blade chamber 22b and the rear end portion is Since it is located in the vertical hole 24b of the blade chamber 22b, it receives the pressure in the case directly.

  Furthermore, the tip of the blade 15b faces the second cylinder chamber 14b, and the blade tip receives the pressure in the cylinder chamber 14b. Eventually, the blade 15b is configured to move in the direction from the higher pressure to the lower pressure according to the magnitude of the mutual pressure received by the front end and the rear end.

  From the differential pressure between the suction pressure that is provided adjacent to the vertical hole 24b of the blade chamber 22b provided in the second cylinder 8B and is guided to the cylinder chamber 14b during normal operation and the pressure in the sealed case 1 that is guided to the blade chamber 22b. A holding mechanism 35 that urges the blade 15b in the direction of pulling away from the eccentric roller 13a with a small force is provided. The holding mechanism 35 may be a permanent magnet, an electromagnet, or an elastic body.

  In other words, the holding mechanism 35 moves the blade 15 away from the eccentric roller 13 with a force smaller than the differential pressure between the suction pressure applied to the second cylinder chamber 14 b and the pressure inside the sealed case 1 applied to the blade groove 22. Keep energized. By providing a permanent magnet as the holding mechanism 35, the blade 15 is always magnetically attracted with a predetermined force.

  Alternatively, an electromagnet may be provided instead of the permanent magnet, and magnetic attraction may be performed as necessary. Alternatively, the holding mechanism 35 is a tension spring that is an elastic body. One end portion of the tension spring may be hooked on the rear end portion of the blade 15 so that the tension spring is always pulled with a predetermined elastic force.

  Each cylinder 8A, 8B is provided with a mounting hole or screw hole through which the mounting bolts 10, 12 are inserted or screwed, and only the first cylinder 8A is provided with an arc-shaped gas passage hole 27.

  As shown in FIG. 1 again, the hermetic rotary compressor R includes a high-pressure introduction passage (high-pressure introduction means) P formed of a pipe, and an electromagnetic on-off valve (opening-closing means) is provided in the middle of the high-pressure introduction passage. ) 28 is provided to open and close the high pressure introduction passage P.

  The high-pressure introduction passage P will be further described. One end of the high-pressure introduction passage P passes through the sealed case 1 and faces the inside. The high-pressure introduction passage P extends to the lower side along the axial direction in parallel with the outer peripheral surface of the sealed case 1, and the electromagnetic on-off valve 28 is provided in the middle portion.

  The other end portion of the high-pressure introduction passage P extends through the sealing case 1 again in the lower portion of the sealing case 1 and is further formed in the second cylinder 8B constituting the second compression mechanism portion 2B. It is connected to the hole e, which is an opening, and directly opens into the second cylinder chamber 14b.

  FIG. 5 is a diagram showing the setting conditions of the connection position of the hole e that constitutes the opening of the high-pressure introduction passage P and the suction hole d to which the suction pipe 16b is connected to the second cylinder 8B. That is, the hole e constituting the opening of the high-pressure introduction passage P is closed by the eccentric roller 13b within a range in which the eccentric roller 13b rotates 90 degrees from the position where the suction hole d closes (the compression start position) ( The hole e is provided at a position where the hole e is separated from the compression chamber.

  As shown in FIG. 1 again, the hermetic rotary compressor R configured as described above is incorporated in the refrigeration cycle circuit of the refrigeration cycle apparatus. That is, the discharge pipe 18 is connected to the upper end portion of the sealed case 1. The discharge pipe 18 is connected to the accumulator 17 via a condenser 19, an expansion mechanism 20 and an evaporator 21.

  Suction pipes 16 a and 16 b for the compressor R are connected to the bottom of the accumulator 17. One suction pipe 16a penetrates the sealed case 1 and directly communicates with the first cylinder chamber 14a through a suction hole formed in the first cylinder 8A. The other suction pipe 16b includes a check valve 29 in the middle and is connected to the hermetic rotary compressor R. That is, the suction pipe 16b passes through the sealed case 1 and directly communicates with the second cylinder chamber 14b through the suction hole d formed in the second cylinder 8B. As shown only in FIG. 5, the hole e opened to the second cylinder chamber 14b of the high pressure introduction passage P is connected to a position near the suction pipe 16b.

A pressure switching mechanism K is constituted by the high-pressure introduction passage P provided with the electromagnetic on-off valve 28 in the middle part and the suction pipe 16b connected to the second cylinder chamber 14b and provided with the check valve 29 in the middle part. In response to the opening / closing operation of the electromagnetic switching valve 28, which is the switching operation of the pressure switching mechanism K, the high pressure gas discharged into the sealed case 1 is introduced into the second cylinder chamber 14b as described later, or the accumulator 17 is turned on. The low-pressure gas that has passed through is guided.
Next, the operation of the refrigeration cycle apparatus provided with the above-described hermetic rotary compressor R will be described.
(1) When normal operation (full capacity operation) is selected:
FIG. 3 is a diagram for explaining the operation at this time. The upper part of FIG. 3 schematically shows the action and the flow of refrigerant in the hermetic rotary compressor R and the accumulator 17, and the lower part of FIG. The operation | movement in the compression mechanism part 2B is shown roughly.
When normal operation (full capacity operation) is selected, the control unit 40 controls to close the electromagnetic on-off valve 28 provided in the high pressure introduction passage P, and the control unit 40 further controls the motor unit 3 via the inverter 30. Send an operation signal to the inverter circuit. The rotary shaft 4 is rotationally driven, and the first compression mechanism 2A and the second compression mechanism 2B act simultaneously.

  That is, the eccentric rollers 13a and 13b rotate eccentrically in the cylinder chambers 14a and 14b. In the first compression mechanism portion 2A, since the blade 15a is always elastically pressed and biased by the spring member 26, the tip edge of the blade 15a is slidably contacted with the peripheral wall of the eccentric roller 13a so as to be in the first cylinder chamber 14a. Is divided into a suction chamber and a compression chamber. When the position of the inner circumferential surface of the eccentric roller 13a in contact with the blade housing groove 23a coincides with the blade housing groove 23a, the space capacity of the cylinder chamber 14a is maximized. The refrigerant gas is sucked into the first cylinder chamber 14a from the accumulator 17 through the first suction pipe 16a and is filled.

  With the eccentric rotation of the eccentric roller 13a, the rolling contact position of the eccentric roller with respect to the inner peripheral surface of the first cylinder chamber 14a moves, and the volume of the compression chamber partitioned by the cylinder chamber 14a decreases. That is, the gas previously introduced into the cylinder chamber 14a is gradually compressed. The rotating shaft 4 is continuously rotated, the capacity of the compression chamber in the first cylinder chamber 14a is further reduced, the gas is compressed, and when the pressure rises to a predetermined pressure, a discharge valve (not shown) is opened. The high-pressure gas is discharged into the sealed case 1 through the valve cover a and is filled. And it discharges from the discharge pipe 18 of an airtight case upper part.

  Further, since the electromagnetic on-off valve 28 provided in the high pressure introduction passage P is closed, even if the high pressure gas filling the sealed case 1 enters from one end portion of the high pressure introduction passage P, it is shut off in the middle. The discharge pressure (high pressure) is not led to the second cylinder chamber 14b which is the other end.

  On the other hand, the low-pressure evaporative refrigerant evaporated by the evaporator 21 and gas-liquid separated by the accumulator 17 is supplied to the second compression mechanism portion 2B from the second suction pipe 16b via the check valve 29. It is guided to the cylinder chamber 14b. While the second cylinder chamber 14b is in a suction pressure (low pressure) atmosphere, the blade chamber 22b is exposed in the sealed case 1 and is under a discharge pressure (high pressure). In the blade 15b, the front end portion is under a low pressure condition and the rear end portion is under a high pressure condition, and there is a differential pressure at the front and rear end portions.

  Due to the effect of this differential pressure, the tip of the blade 15b is pressed and urged so as to be in sliding contact with the eccentric roller 13b. That is, the same compression action is performed in the second cylinder chamber 14b as the blade 15a on the first cylinder chamber 14a side is pressed and urged by the spring member 26 to perform the compression action. Eventually, in the hermetic rotary compressor R, full capacity operation is performed in which the compression action is performed by both the first compression mechanism 2A and the second compression mechanism 2B.

  The high-pressure gas discharged from the sealed case 1 through the discharge pipe 18 is led to the condenser 19 to be condensed and liquefied, adiabatically expanded by the expansion mechanism 20, and the evaporator 21 takes away latent heat of evaporation from the heat exchange air and cools it. It works. The evaporated refrigerant is guided to the accumulator 17 for gas-liquid separation, and is again sucked into the first and second compression mechanism portions 2A and 2B of the compressor R from the suction pipes 16a and 16b. Circulate.

(2) When special operation (half-capacity operation) is selected:
FIG. 4 is a diagram for explaining the operation at this time. The upper part of the figure schematically shows the action and the refrigerant flow in the hermetic rotary compressor R and the accumulator 17, and the lower part of the figure shows the second part. The operation | movement in the compression mechanism part 2B is shown roughly.

  When the special operation (capability half operation) is selected, the control unit 40 switches and sets the on-off valve 28 provided in the high-pressure introduction passage P to be opened. In the first compression mechanism portion 2A, the normal compression action is performed as described above, and the high-pressure gas discharged into the sealed case 1 is filled to become the high pressure in the case.

  The high-pressure gas filling the sealed case 1 is discharged from the discharge pipe 18, but a part of the high-pressure gas is directly guided from the sealed case 1 to the high-pressure introduction passage P and opened via the electromagnetic on-off valve 28 that is opened. Are introduced into the second cylinder chamber 14b. While the second cylinder chamber 14b is in a discharge pressure (high pressure) atmosphere, the blade chamber 22b remains in the same situation as the high pressure in the case.

  Therefore, the blade 15b is affected by the high pressure at both the front and rear ends, and there is no differential pressure at the front and rear ends. The blade 15b maintains a stopped state without moving at a position separated from the outer peripheral surface of the eccentric roller 13b, and the second cylinder chamber 14b is not compressed and the second compression mechanism 2B is in a stopped state. Eventually, only the compression action in the first compression mechanism portion 2A is effective, and an operation with half the capacity is performed.

  A part of the high-pressure gas filled in the second cylinder chamber 14 b flows back to the second suction pipe 16 b and tries to return to the accumulator 17. However, since the check pipe 29 is provided in the suction pipe 16b, the backflow to the accumulator is prevented. Further, since the inside of the second cylinder chamber 14b is at a high pressure, no leakage of compressed gas from the sealed case 1 to the second cylinder chamber 14b occurs, and no loss is caused thereby. Therefore, it is possible to operate with half the capacity without lowering the compression efficiency.

  Unlike a conventional compressor, a complicated mechanism for fixing the blade to one compression mechanism at the top dead center is not required, and a spring member for biasing the blade can be omitted. Moreover, the pressure switching mechanism K is configured by communicating the high pressure introduction passage P provided with the electromagnetic opening / closing valve 29 in the middle between the sealed case 1 and the second cylinder chamber 14b and providing the check valve 29 in the suction pipe 16b. In addition, the capacity can be varied with a simple structure, which is advantageous in terms of cost, is excellent in manufacturability, and can provide a highly efficient hermetic rotary compressor.

  In addition, although the hole e which is one end opening part of the said high voltage | pressure introduction channel | path P was provided in the 2nd cylinder 8B, it is not limited to this.

  FIG. 6 is a side view of a compression mechanism showing another embodiment of the present invention. For example, as shown in FIG. 6, a hole 50 is provided in the intermediate partition plate 7 interposed between the first compression mechanism 2 </ b> A and the second compression mechanism 2 </ b> B, and the end of the high pressure introduction passage P is provided here. May be connected.

  The hole 50 provided in the intermediate partition plate 7 has one end opened to the peripheral surface and connected to the high pressure introduction passage P, and the other end opened to the second cylinder chamber 14b. The position of the hole 50 opened in the peripheral surface of the intermediate partition plate 7 is further rotated 90 degrees from the position (compression start position) where the eccentric roller 13b closes the suction hole opened in the second cylinder chamber 14b, as described above. Within a range of a predetermined angle θ from the connection position of the suction pipe 16a communicating with the first compression mechanism 2A and the suction pipe 16b connected to the second compression mechanism 2B so as to be closed by the eccentric roller 13b. Needless to say.

  Furthermore, for example, the auxiliary bearing 11 may be provided as a hole to which one end of the high pressure introduction passage P is connected. Since the hole position selection conditions are the same as those provided in the second cylinder 8B or the intermediate partition plate 7, a new description is omitted here.

  In any case, by providing the above-described hermetic rotary compressor R, at least one compression mechanism part (2B) of the plurality of compression mechanism parts 2A, 2B is operated in an idle operation (non-compression operation). Since the high pressure introduction passage P is directly opened in the predetermined cylinder (8B), the normal operation and the non-compression operation in which the compression operation is not performed can be switched without using a complicated piping structure.

The high-pressure introduction passage P has a dead clearance volume that causes re-expansion loss during normal operation, but is opened at a position where the eccentric roller 13b is closed by the eccentric roller 13b within a range in which the eccentric roller 13b rotates 90 degrees from the position where the suction hole d is closed. By providing the hole e which is a portion, this loss can be made extremely small. Since the high-pressure introduction passage can be shortened, the gas just discharged to the sealed case 1 can be guided to the cylinder chamber without causing pressure loss, and the pressure difference acting on the blade tip and back is almost eliminated. be able to.
Further, during a special operation (a half-capacity operation) in which the second compression mechanism unit 2B is in the idling (non-compression operation) state, the holding force of the holding mechanism 35 that holds the blade 15b of the second compression mechanism unit 2B is It's small. That is, when a magnet is used as the holding mechanism 35, the magnetic attraction force is small, and the magnet can be miniaturized. Since the magnetic attractive force can be reduced, the pressure applied in the opposite direction to the magnetic force can be reduced, and the switching from normal operation (full capacity operation) to special operation (capability half operation) is improved.

  Furthermore, it is not necessary to connect a branch pipe to the midway part of the 2nd suction pipe 16b which connects the accumulator 17 and the compressor R which comprise a refrigerating cycle. That is, as a means for directly introducing the high pressure gas into the second cylinder chamber 14b, one end of the high pressure introduction passage is branched and connected to the discharge pipe 18 connected to the sealed case 1, and the other end is connected to the second suction pipe 16b. It is conceivable that the high pressure of the refrigeration cycle is led to the second suction pipe by branching to

  In this case, it is conceivable that the suction passage in the second compression mechanism portion 2B becomes particularly long, the suction resistance during normal operation increases, and the efficiency decreases. Therefore, the suction pipe 16b has only to be provided with a minimum length, there is no suction loss, and the height of the compressor R can be reduced.

  When the above configuration is adopted, the high-pressure introduction passage becomes longer, and the pressure in the cylinder chamber becomes smaller than the pressure in the sealed case acting on the back surface of the blade due to pressure loss. Therefore, although the blade is likely to rattle during non-compression operation, as a countermeasure, if the holding force of the holding mechanism 35 holding the blade is increased, switching from the special operation to the normal operation cannot be performed smoothly. And since the connection location of piping increases, malfunctions, such as bad manufacturability, will arise.

  According to the present invention, it is possible to switch between a normal operation and a non-compression operation in which a compression operation is not performed without using a complicated piping structure, and without increasing the suction passage resistance, the compression work during the normal operation There is an effect such as not affecting.

Claims (2)

In the sealed case, the motor unit and the plurality of compression mechanism units are connected and accommodated via the rotating shaft,
At least one compression mechanism section is
The blade is pressed and biased by the pressure difference between the pressure in the sealed case that acts on the back surface of the blade and the pressure in the cylinder chamber that acts on the tip of the blade,
Normal operation in which low-pressure refrigerant is introduced into the cylinder chamber via a suction hole to perform compression operation, high-pressure refrigerant is introduced into the cylinder chamber, and the pressure in the sealed case acting on the back of the blade is guided to the cylinder chamber The pressure of the high-pressure refrigerant is balanced and the pressure is balanced at the front and rear ends of the blade, and the leading edge of the blade is separated from the outer peripheral surface of the eccentric roller and can be switched to a non-compression operation where the compression operation is not performed. In a hermetic rotary compressor,
A high-pressure introduction passage having one end directly opened in the cylinder chamber of the compression mechanism portion enabling the operation switching, and the other end communicating with the sealed case;
An opening / closing means provided in the middle of the high-pressure introduction passage, for opening and closing the high-pressure introduction passage;
A hermetic rotary compressor characterized by comprising: One end opening of the high-pressure introduction passage is formed in a cylinder constituting the compression mechanism part, an intermediate partition plate interposed between the plurality of compression mechanism parts, or a bearing supporting the rotating shaft, and is eccentric. 2. The hermetic rotary compressor according to claim 1, wherein the roller is provided at a position that is closed by an eccentric roller within a range in which the roller is further rotated 90 degrees from a position at which the suction hole is closed.

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