JP2004084568A - Multistage compression type rotary compressor and displacement capacity ratio setting method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multistage compression type rotary compressor capable of easily setting an optimum displacement capacity ratio while reducing the cost and improving the workability, and a displacement capacity ratio setting method therefor. <P>SOLUTION: In this multistage compression type rotary compressor, an eccentric part (second eccentric part) 42, an eccentric part (first eccentric part) 44, a roller (second roller) 46, a roller (first roller) 48, an upper cylinder 38, and a lower cylinder (first cylinder) 40 have the same dimension. The upper cylinder 38 is extended outward within a prescribed angle range from an intake port 161 in the rotating direction of the second roller 46 to constitute an extension part 100. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a multi-stage compression type rotary compressor which sucks refrigerant gas compressed and discharged by a first rotary compression element into a second rotary compression element, compresses and discharges the refrigerant gas, and a method of setting an excluded volume ratio thereof. It is.
[0002]
[Prior art]
In this type of conventional multi-stage compression type rotary compressor, as shown in FIG. , And becomes an intermediate pressure, and is discharged from the discharge port 272 on the high pressure chamber side of the cylinder 240. The intermediate-pressure refrigerant gas is sucked from the suction port 261 of the second rotary compression element 234 into the low-pressure chamber side of the cylinder 238, where the second-stage compression is performed by the operation of the roller 246 and the vane 250, and It becomes high-pressure refrigerant gas and is discharged from the discharge port 270 on the high-pressure chamber side. Then, the refrigerant discharged from the compressor flows into a radiator, radiates heat, is throttled by an expansion valve, absorbs heat by an evaporator, and sucks the refrigerant into the first rotary compression element 232. In FIG. 5, reference numeral 216 denotes a rotating shaft of the electric element, and reference numerals 227 and 228 denote discharge valves provided in the discharge muffling chambers 262 and 264 for closing the discharge ports 270 and 272 in an openable and closable manner.
[0003]
Here, the excluded volume of the second rotary compression element 234 is set to be smaller than the excluded volume of the first rotary compression element 232. In this case, conventionally, the thickness (height) of the cylinder 240 of the first rotary compression element 232 is made thicker (higher) than the thickness of the cylinder 238 of the second rotary compression element 234, or the second rotation. The inner diameter of the cylinder 238 of the compression element 234 is made smaller than the inner diameter of the cylinder 240 of the first rotary compression element 232, or the amount of eccentricity of the roller 246 of the second rotary compression element 234 is made smaller (the outer diameter of the roller 246 is made larger). For example, the displacement volume of the second rotary compression element 234 is set to be smaller than the displacement volume of the first rotary compression element 232.
[0004]
[Problems to be solved by the invention]
However, the rejection volume ratio of such a multi-stage compression type rotary compressor has an optimum value depending on the application, and in each case, the parts such as the eccentricity of the rotating shaft, the outer diameter of the roller, or the inner diameter and height of the cylinder are changed (material type). , Changes in processing equipment, measuring instruments, etc.). Further, since the eccentric amounts of the rotating shafts of the first rotary compression element and the second rotary compression element are different, the setup and processing man-hours for processing the rotary shaft have been increased.
[0005]
For this reason, there has been a problem that costs (including costs for changing material types, processing equipment, measuring instruments, and the like) are increased due to an increase in working time and a change in parts due to the change of parts.
[0006]
The present invention has been made in order to solve the problems of the related art, and has a multi-stage compression type rotary compressor which can easily set an optimum excluded volume ratio while reducing costs and improving workability. An object of the present invention is to provide a method for setting the excluded volume ratio.
[0007]
[Means for Solving the Problems]
That is, in the multistage compression type rotary compressor according to the first aspect of the present invention, the first and second eccentric portions, the first and second rollers, and the first and second cylinders have the same dimensions, respectively. Since the second cylinder is extended outward from the suction port within a range of a predetermined angle in the rotation direction of the second roller, the compression of the refrigerant in the cylinder of the second rotary compression element is delayed.
[0008]
In the method according to the second aspect of the present invention, the second cylinder is extended outward from the suction port within a range of a predetermined angle in the rotation direction of the second roller, and the compression start angle of the second rotary compression element is adjusted. Thus, the ratio of the excluded volume of the first and second rotary compression elements is set, so that the compression start of the refrigerant in the cylinder of the second rotary compression element is delayed, and the excluded volume of the second rotary compression element is reduced. It can be reduced.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a longitudinal sectional view of an internal intermediate pressure type multi-stage (two-stage) compression type rotary compressor 10 having first and second rotary compression elements 32 and 34 as an embodiment of a multi-stage compression type rotary compressor of the present invention. 2 is a refrigerant circuit diagram when the present invention is applied to a water heater 153, FIG. 3 is a sectional view of cylinders of first and second rotary compression elements of a single-stage two-cylinder rotary compressor, and FIG. The cross-sectional views of the cylinder (first cylinder) 40 of the first rotary compression element 32 and the cylinder (second cylinder) 38 of the second rotary compression element 34 of the multi-stage compression type rotary compressor 10 to which the present invention is applied are shown. I have.
[0010]
In FIG. 1, reference numeral 10 denotes an internal intermediate pressure type multi-stage compression type rotary compressor. The multi-stage compression type rotary compressor 10 has a cylindrical hermetic container 12A made of a steel plate, and a substantially bowl-like shape closing the upper opening of the hermetic container 12A. An airtight container 12 as a case formed by an end cap (lid) 12B; an electric element 14 arranged and housed above the inner space of a container body 12A of the airtight container 12; And a rotary compression mechanism 18 including a first rotary compression element 32 and a second rotary compression element 34 driven by the rotary shaft 16 of the electric element 14.
[0011]
The closed container 12 has an oil reservoir at the bottom. A circular mounting hole 12D is formed in the center of the upper surface of the end cap 12B, and a terminal (wiring is omitted) 20 for supplying electric power to the electric element 14 is mounted in the mounting hole 12D.
[0012]
The electric element 14 includes a stator 22 annularly mounted along the inner surface of the upper space of the closed casing 12, and a rotor 24 inserted and installed with a slight gap inside the stator 22. The rotating shaft 16 extending in the vertical direction is fixed to the rotor 24.
[0013]
The stator 22 has a laminated body 26 in which donut-shaped electromagnetic steel sheets are laminated, and a stator coil 28 wound around teeth of the laminated body 26 by a direct winding (concentrated winding) method. The rotor 24 is also formed of a laminated body 30 of electromagnetic steel sheets, like the stator 22, and is formed by inserting a permanent magnet MG into the laminated body 30. After the permanent magnet MG is inserted into the laminated body 30, the upper and lower end surfaces of the laminated body 30 are covered with a non-magnetic end face member (not shown). A balance weight 101 (the balance weight on the lower side of the laminate 30 is not shown) is attached, and an oil separation plate 102 is attached on the balance weight 101 located above the laminate 30 by overlapping.
[0014]
The rotor 24, the balance weight 101, and the rivet 104 penetrating the oil separating plate 102 are integrally connected to each other.
[0015]
On the other hand, an intermediate partition plate 36 is held between the first rotary compression element 32 and the second rotary compression element 34. That is, the first rotary compression element 32 and the second rotary compression element 34 include an intermediate partition plate 36, upper and lower cylinders 38 and 40 disposed above and below the intermediate partition plate 36, and as shown in FIG. An eccentric portion (second eccentric portion) 42 and an eccentric portion (first eccentric portion) 44 provided on the rotating shaft 16 so as to rotate the cylinders 38 and 40 with a phase difference of 180 degrees. An upper roller (second roller) 46 and a lower roller (first roller) 48 that are eccentrically rotated in combination and contact the upper and lower rollers 46, 48 to move the inside of the upper and lower cylinders 38, 40 to the low pressure chamber side and the high pressure cylinder, respectively. Vanes 50 and 52 partitioned on the chamber side, an upper support member 54 as a support member that also serves as a bearing for the rotary shaft 16 by closing the upper opening surface of the upper cylinder 38 and the lower opening surface of the lower cylinder 40. The lower support member 56 is used.
[0016]
Here, as shown in FIG. 3, the first rotary compression element and the second rotary compression element 32, 34 are described later in the first and second rotary compression elements 32, 34 of a single-stage two-cylinder rotary compressor. An unillustrated communication path or the like for discharging the refrigerant compressed by the expansion unit 100 or the first rotary compression element into the closed container is used.
[0017]
The single-stage two-cylinder rotary compressor is connected to a low-pressure chamber side of the cylinder 40 of the first rotary compression element 32 or a cylinder of the second rotary compression element 34 through suction ports 161 and 162 from a suction passage (not shown). Refrigerant gas is sucked into the low-pressure chamber side 38. The refrigerant gas sucked into the low pressure chamber side of the cylinder 40 is compressed by the operation of the roller 48 and the vane 52 to a high pressure, and is discharged from the high pressure chamber side of the cylinder 40 to the discharge muffling chamber 64 via the discharge port 41. Thereafter, the refrigerant gas is discharged to the discharge muffling chamber 62 through a passage (not shown) and merges with the refrigerant gas compressed in the cylinder 38.
[0018]
On the other hand, the refrigerant gas sucked into the low pressure chamber side of the cylinder 38 is compressed by the operation of the roller 46 and the vane 50 to a high pressure, and is discharged from the high pressure chamber side of the cylinder 38 to the discharge muffling chamber 62 through the discharge port 39, The refrigerant merges with the refrigerant gas compressed in the cylinder 40 described above. The combined high-pressure refrigerant gas is discharged from the discharge pipe (not shown) to the closed container 12.
[0019]
The first and second rotary compression elements 32 and 34 of the single-stage two-cylinder rotary compressor have the same excluded volume. That is, the eccentric portions 42, 44 of the first and second rotary compression elements 32, 34, the rollers 46, 48, and the cylinders 38, 40 have the same dimensions.
[0020]
Therefore, when the rotary compression elements 32, 34 of the single-stage rotary compressor are used in the multi-stage compression type rotary compressor 10, the excluded volume ratio of the first and second rotary compression elements 32, 34 must be changed. That is, when the rejected volumes of the first and second rotary compression elements 32 and 34 are the same volume, the step pressure of the second stage (the suction pressure of the second rotary compression element and the discharge pressure of the second rotary compression element) (Difference), the compression load of the second rotary compression element increases, or the oil pressure to the rotary compression mechanism 18 becomes insufficient due to the differential pressure, resulting in reduced durability and reliability. Occurs. For this reason, the displacement volume of the second rotary compression element 34 must be set to be smaller than the displacement volume of the first rotary compression element 32 to suppress the step pressure in the second stage.
[0021]
In this case, an extension 100 is formed in the upper cylinder 38 as shown in FIG. The extension portion 100 extends the outside of the upper cylinder 38 within a range of a predetermined angle in the rotation direction of the roller 46 from the suction port 161 of the upper cylinder 38. The expansion section 100 can delay the compression start angle of the refrigerant gas in the upper cylinder 38 to the rotation direction end of the roller 46 of the expansion section 100. That is, the start of the compression of the refrigerant in the upper cylinder 38 can be delayed by the angle at which the extension 100 of the upper cylinder 38 is formed.
[0022]
Therefore, the amount of the refrigerant gas compressed in the upper cylinder 38 can be reduced, and as a result, the displacement volume of the second rotary compression element 34 can be reduced.
[0023]
Thus, even if the eccentric portions 42, 44, the rollers 46, 48, and the upper and lower cylinders 38, 40 of the first and second rotary compression elements 32, 34 have the same dimensions, the displacement volume of the second rotary compression element 34 can be reduced. By making the displacement volume smaller than the displacement volume of the first rotary compression element 32, it is possible to prevent an increase in the step pressure of the second stage (difference between the suction pressure of the second rotary compression element and the discharge pressure of the second rotary compression element). become able to.
[0024]
That is, since the displacement volume of the second rotary compression element 34 can be reduced only by forming the expansion portion 100 in the upper cylinder 38, the first and second rotary compression elements 32 of the single-stage two-cylinder rotary compressor are reduced. , 34 can be diverted to the multi-stage compression type rotary compressor 10 by only partially processing it.
[0025]
As described above, by merely expanding the upper cylinder 38 of the second rotary compression element 34 as appropriate to form the expansion portion 100, the displacement volume of the second rotary compression element 34 is made smaller than that of the first rotary compression element 32. As a result, the cost for setting the excluded volume ratio of the first and second rotary compression elements 32 and 34 can be reduced.
[0026]
Further, since the eccentric portions 42 and 44 of the rotary shaft 16 of the first rotary compression element and the second rotary compression elements 32 and 34 have the same dimensions, the workability of the rotary shaft 16 is improved. Can be reduced in production cost and productivity can be improved.
[0027]
The upper support member 54 and the lower support member 56 have a suction passage 60 (not shown) that communicates with the insides of the upper and lower cylinders 38 and 40 at the suction ports 161 and 162, respectively. Discharge silence chambers 62 and 64 formed by closing the concave portion of the lower support member 56 with a cover as a wall are provided. That is, the discharge muffling chamber 62 is closed by the upper cover 66 as a wall defining the discharge muffling chamber 62, and the discharge muffling chamber 64 is closed by the lower cover 68.
[0028]
In this case, a bearing 54 </ b> A is formed upright at the center of the upper support member 54. A bearing 56A is formed through the center of the lower support member 56, and the rotating shaft 16 is held by a bearing 54A of the upper support member 54 and a bearing 56A of the lower support member 56.
[0029]
The lower cover 68 is made of a donut-shaped circular steel plate, and four peripheral portions are fixed to the lower support member 56 from below by main bolts 129. A discharge silence chamber 64 that communicates with the interior of the lower cylinder 40 of the element 32 is defined. The tips of the main bolts 129 are screwed into the upper support member 54.
[0030]
A discharge valve 128 (shown on the same plane as the cylinder for description in FIGS. 3 and 4) is provided on the upper surface of the discharge muffling chamber 64 so as to open and close the discharge port 41. The discharge valve 128 is made of an elastic member made of a metal plate having a vertically-long and substantially rectangular shape. One side of the discharge valve 128 abuts on the discharge port 41 to seal it, and the other side has a predetermined distance from the discharge port 41. And is fixed to a mounting hole (not shown) of the lower support member 56 with a caulking pin.
[0031]
A backer valve 128A as a discharge valve suppressing plate is disposed below the discharge valve 128, and is attached to the lower support member 56 in the same manner as the discharge valve 128.
[0032]
Then, the refrigerant gas compressed in the lower cylinder 40 and reaching a predetermined pressure pushes the discharge valve 128 that closes the discharge port 41 to open the discharge port 41 and discharge the gas to the discharge muffling chamber 64. At this time, since the other side of the discharge valve 128 is fixed to the lower support member 56, one side that is in contact with the discharge port 41 bends and contacts the backer valve 128 A that regulates the opening amount of the discharge valve 128. . When it is time to end the discharge of the refrigerant gas, the discharge valve 128 separates from the backer valve 128A and closes the discharge port 41.
[0033]
The discharge muffling chamber 64 of the first rotary compression element 32 and the inside of the sealed container 12 are communicated with each other through the above-described communication path, and this communication path includes the upper support member 54, the upper cover 66, the upper and lower cylinders 38, 40, It is a hole (not shown) penetrating the partition plate 36. In this case, an intermediate discharge pipe 121 is provided upright at the upper end of the communication path, and an intermediate-pressure refrigerant is discharged from the intermediate discharge pipe 121 into the closed container 12.
[0034]
The upper cover 66 defines a discharge muffling chamber 62 that communicates with the inside of the upper cylinder 38 of the second rotary compression element 34 at the discharge port 39. Above the upper cover 66, a predetermined distance from the upper cover 66 is provided. Therefore, the electric element 14 is provided. The upper cover 66 is formed of a substantially donut-shaped circular steel plate having a hole through which the bearing 54A of the upper support member 54 penetrates, and its peripheral portion is formed by four main bolts 78. It is fixed to the support member 54. The tips of the main bolts 78 are screwed into the lower support member 56.
[0035]
A discharge valve 127 (shown on the same plane as the cylinder in FIGS. 3 and 4 for explanation) is provided on the lower surface of the discharge muffling chamber 62 to open and close the discharge port 39. The discharge valve 127 is made of an elastic member made of a metal plate having a vertically-long, substantially rectangular shape. One side of the discharge valve 127 is in contact with and tightly closed to the discharge port 39, and the other side is at a predetermined distance from the discharge port 39. And is fixed to a mounting hole (not shown) of the upper support member 54 with a caulking pin.
[0036]
A backer valve 127A as a discharge valve suppressing plate is disposed above the discharge valve 127, and is attached to the upper support member 54 in the same manner as the discharge valve 127.
[0037]
The refrigerant gas which has been compressed in the upper cylinder 38 and has reached a predetermined pressure is supplied to a discharge valve 127 closing the discharge port 39 (for the sake of explanation, FIGS. 3 and 4 show the same plane as the cylinder. ) To open the discharge port 39 and discharge the liquid to the discharge muffling chamber 62. At this time, since the other side of the discharge valve 127 is fixed to the upper support member 54, one side of the discharge valve 127 that is in contact with the discharge port 39 bends and contacts the backer valve 127A that regulates the opening amount of the discharge valve 127. . When it is time to end the discharge of the refrigerant gas, the discharge valve 127 separates from the backer valve 127A and closes the discharge port 39.
[0038]
On the other hand, in the upper and lower cylinders 38 and 40, a guide groove (not shown) for storing the vanes 50 and 52 and storage portions 70 and 72 for storing springs 76 and 78 as spring members located outside the guide grooves are formed. Have been. The storage portions 70 and 72 are open on the guide groove side and the closed container 12 (container body 12A) side. The springs 76 and 78 abut against the outer ends of the vanes 50 and 52 and constantly bias the vanes 50 and 52 toward the rollers 46 and 48. Metal plugs 137 and 140 are provided in the storage portions 70 and 72 of the springs 76 and 78 on the closed container 12 side, and serve to prevent the springs 76 and 78 from coming off.
[0039]
In this case, as the refrigerant, an existing refrigerant such as an HC refrigerant, an HC-based mixed refrigerant, a CO ₂ refrigerant, and a CO ₂ mixed refrigerant is used.
[0040]
Further, on the side surface of the container body 12A of the closed container 12, the suction passages 60 (the upper side is not shown) of the upper supporting member 54 and the lower supporting member 56, the discharge muffling chamber 62, and the upper side of the upper cover 66 (the upper side of the electric element 14). The sleeves 141, 142, 143, and 144 are respectively welded and fixed at positions corresponding to the lower end (positions substantially corresponding to the lower ends). The sleeves 141 and 142 are vertically adjacent to each other, and the sleeve 143 is substantially on a diagonal line of the sleeve 141. The sleeve 144 is located at a position shifted from the sleeve 141 by approximately 90 degrees.
[0041]
One end of a refrigerant introduction pipe 92 for introducing refrigerant gas into the upper cylinder 38 is inserted into the sleeve 141, and one end of the refrigerant introduction pipe 92 communicates with a suction passage (not shown) of the upper cylinder 38. The refrigerant introduction pipe 92 passes through the upper side of the closed container 12 to reach the sleeve 144, and the other end is inserted and connected into the sleeve 144 and communicates with the inside of the closed container 12.
[0042]
One end of a refrigerant introduction pipe 94 for introducing refrigerant gas into the lower cylinder 40 is inserted and connected into the sleeve 142, and one end of the refrigerant introduction pipe 94 communicates with the suction passage 60 of the lower cylinder 40. The other end of the refrigerant introduction pipe 94 is connected to a lower end of an accumulator (not shown). A coolant discharge pipe 96 is inserted and connected into the sleeve 143, and one end of the coolant introduction pipe 96 communicates with the discharge muffling chamber 62.
[0043]
Next, the multi-stage compression type rotary compressor 10 described above with reference to FIG. 2 forms a part of a refrigerant circuit of the hot water supply device 153 illustrated in FIG.
[0044]
That is, the refrigerant discharge pipe 96 of the multi-stage compression type rotary compressor 10 is connected to the gas cooler 154. The gas cooler 154 is provided in a hot water storage tank (not shown) of the hot water supply device 153 for heating water to generate hot water. The pipe exiting the gas cooler 154 is connected to an evaporator 157 via an expansion valve 156 as a decompression device, and the evaporator 157 is connected to a refrigerant introduction pipe 94 via an accumulator (not shown).
[0045]
Next, the operation of the above configuration will be described. When the stator coil 28 of the electric element 14 is energized through the terminal 20 and the wiring (not shown), the electric element 14 is activated and the rotor 24 rotates. By this rotation, the upper and lower rollers 46 and 48 are eccentrically rotated in the upper and lower cylinders 38 and 40 by being fitted to the upper and lower eccentric portions 42 and 44 provided integrally with the rotating shaft 16.
[0046]
Accordingly, the low-pressure refrigerant sucked from the suction port 162 to the low-pressure chamber side of the lower cylinder 40 via the suction passage 60 formed in the lower support member 56 is compressed by the operation of the lower roller 48 and the lower vane 52. To an intermediate pressure. As a result, the discharge valve 128 provided in the discharge muffle chamber 64 is opened, and the discharge muffle chamber 64 communicates with the discharge port 41. Therefore, the lower support member 56 passes through the discharge port 41 from the high pressure chamber side of the lower cylinder 40. Is discharged to the discharge muffling chamber 64 formed at the bottom. The refrigerant gas discharged into the discharge muffling chamber 64 is discharged from the intermediate discharge pipe 121 into the closed container 12 through a communication hole (not shown).
[0047]
Then, the intermediate-pressure refrigerant gas in the sealed container 12 is sucked from the suction port 161 to the low-pressure chamber side of the upper cylinder 38 from the suction port 161 through the refrigerant pipe 92 and the suction passage (not shown) formed in the upper support member 54. Is done. The sucked intermediate-pressure refrigerant gas is compressed in the second stage by the operation of the upper roller 46 and the upper vane 50, and becomes a high-temperature and high-pressure refrigerant gas. As a result, the discharge valve 127 provided in the discharge muffle chamber 62 is opened, and the discharge muffle chamber 62 communicates with the discharge port 39. Therefore, the upper support member passes through the discharge port 39 from the high pressure chamber side of the upper cylinder 38. The liquid is discharged to the discharge muffling chamber 62 formed at 54.
[0048]
Then, the high-pressure refrigerant gas discharged into the discharge muffling chamber 62 flows into the gas cooler 154 via the refrigerant discharge pipe 96. The refrigerant temperature at this time has risen to approximately + 100 ° C., and the high-temperature and high-pressure refrigerant gas radiates heat from the gas cooler 154 to heat water in a hot water storage tank (not shown) to generate hot water of approximately + 90 ° C.
[0049]
In the gas cooler 154, the refrigerant itself is cooled and exits the gas cooler 154. Then, after the pressure is reduced by the expansion valve 156, it flows into the evaporator 157 and evaporates (at this time, absorbs heat from the surroundings), and is sucked into the first rotary compression element 32 from the refrigerant introduction pipe 94 via an accumulator (not shown). Repeat cycle.
[0050]
As described above, when the rotary compression element of the single-stage two-cylinder rotary compressor is used for the multi-stage compression type rotary compressor, the cylinder 38 that constitutes the second rotary compression element 34 is connected to the suction port 161 through the roller 46. By expanding outward in a range of a predetermined angle in the rotation direction and adjusting the compression start angle of the second rotary compression element 34 to delay the compression start of the refrigerant in the cylinder 38 of the second rotary compression element 34, The displacement volume of the second rotary compression element 34 can be reduced.
[0051]
Thus, the displacement volume of the second rotary compression element 34 can be reduced by the first rotary compression element 32 and the second rotary compression element 34 without changing parts such as the cylinders 38 and 40 and the rollers 46 and 48. Since it can be made smaller than the first rotary compression element 32, it is possible to reduce the cost when setting the excluded volume ratio of the first and second rotary compression elements 32 and 34. .
[0052]
In particular, it is effective for a two-stage compression type rotary compressor in which the excluded volume of the second rotary compression element 34 and the excluded volume of the first rotary compression element 32 are close (high volume ratio).
[0053]
In the embodiment, the rotary compression element of the single-stage two-cylinder type rotary compressor is used as a part of the multi-stage compression type rotary compressor. However, the present invention is not limited to this. The present invention is also effective when a rotary compression element is used.
[0054]
Further, although the multistage compression type rotary compressor 10 in which the rotating shaft 16 is arranged vertically has been described, it goes without saying that the present invention can be applied to a multistage compression type rotary compressor in which the rotating shaft is arranged horizontally.
[0055]
Further, the multi-stage compression type rotary compressor has been described as a two-stage compression type rotary compressor having first and second rotary compression elements. However, the present invention is not limited to this, and three-stage, four-stage or more rotary compression elements may be used. It may be applied to a multi-stage compression type rotary compressor having components.
[0056]
【The invention's effect】
As described in detail above, according to the first aspect of the present invention, the first and second eccentric portions, the first and second rollers, and the first and second cylinders have the same dimensions, respectively. Is extended outward from the suction port within a range of a predetermined angle in the rotation direction of the second roller, so that the start of compression of the refrigerant in the cylinder of the second rotary compression element is delayed.
[0057]
Accordingly, the displacement volume of the second rotary compression element is made smaller than that of the first rotary compression element without changing parts such as cylinders and rollers between the first rotary compression element and the second rotary compression element. Therefore, it is possible to reduce the cost when setting the excluded volume ratio of the first and second rotary compression elements.
[0058]
Further, since the eccentric portions of the rotary shafts of the first rotary compression element and the second rotary compression element have the same dimensions, the workability of the rotary shaft is improved. Can be improved.
[0059]
According to the second aspect of the present invention, the second cylinder is extended outward from the suction port within a range of a predetermined angle in the rotation direction of the second roller to adjust the compression start angle of the second rotary compression element. Thus, the ratio of the excluded volume of the first and second rotary compression elements is set, so that the compression start of the refrigerant in the cylinder of the second rotary compression element is delayed, and the excluded volume of the second rotary compression element is reduced. It can be reduced.
[0060]
Thus, the exclusion volume ratio of the first and second rotary compression elements can be changed without changing parts such as cylinders and rollers between the first rotary compression element and the second rotary compression element. Therefore, it is possible to eliminate an increase in cost due to a component change.
[0061]
Further, as described above, since the eccentric portions of the rotary shafts of the first rotary compression element and the second rotary compression element have the same dimensions, the workability of the rotary shaft is improved. Workability can be improved.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of a multi-stage compression type rotary compressor according to an embodiment of the present invention.
FIG. 2 is a diagram showing a refrigerant cycle of an oil supply device of an embodiment to which the rotary compressor of the present invention is applied.
FIG. 3 is a longitudinal sectional view of cylinders of first and second rotary compression elements of a single-stage two-cylinder rotary compressor.
FIG. 4 is a vertical sectional view of a cylinder of first and second rotary compression elements of the rotary compressor of FIG. 1 to which the present invention is applied.
FIG. 5 is a longitudinal sectional view of a cylinder of first and second rotary compression elements of a conventional multistage compression type rotary compressor.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Multistage compression type rotary compressor 12 Hermetic container 14 Electric element 16 Rotary shaft 18 Rotary compression mechanism 20 Terminal 22 Stator 24 Rotor 26 Stack 28 Stator coil 30 Stack 32 First rotary compression element 34 Second rotary compression element 38 , 40 cylinder 39, 41 discharge port 54 upper support member 56 lower support member 62, 64 discharge muffler chamber 66 upper cover 68 lower cover 100 expansion part 101 balance weight 102 oil separation plate 127, 128 discharge valve 153 water heater 154 gas cooler 156 expansion Valve 157 Evaporator 161, 162 Suction port

Claims (2)

An electric element in a closed container, first and second rotary compression elements driven by a rotating shaft of the electric element, and first and second cylinders forming the first and second rotary compression elements And first and second eccentric portions provided on the rotation shaft so as to rotate with a phase difference in each cylinder, and inside the first and second cylinders fitted to the respective eccentric portions. A multistage compression type comprising: first and second rollers that rotate eccentrically, wherein the refrigerant gas compressed and discharged by the first rotary compression element is sucked into the second rotary compression element, compressed and discharged. In rotary compressors,
The first and second eccentric portions, the first and second rollers, and the first and second cylinders have the same dimensions, respectively.
The multi-stage compression type rotary compressor, wherein the second cylinder extends outward from a suction port within a range of a predetermined angle in a rotation direction of the second roller. An electric element in a closed container, first and second rotary compression elements driven by a rotating shaft of the electric element, and first and second cylinders forming the first and second rotary compression elements And first and second eccentric portions provided on the rotation shaft so as to rotate with a phase difference in each cylinder, and inside the first and second cylinders fitted to the respective eccentric portions. A multistage compression type comprising: first and second rollers that rotate eccentrically, wherein the refrigerant gas compressed and discharged by the first rotary compression element is sucked into the second rotary compression element, compressed and discharged. In rotary compressors,
The first and second eccentric portions, the first and second rollers, and the first and second cylinders have the same dimensions, respectively,
The second cylinder is extended outward from a suction port within a predetermined angle range in the rotation direction of the second roller from the suction port, and the compression start angle of the second rotary compression element is adjusted, whereby the first and the second cylinders are compressed. A method for setting an excluded volume ratio of a multi-stage compression type rotary compressor, comprising setting an excluded volume ratio of a second rotary compression element.

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