JP2006200541A - Hermetic electric compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hermetic electric compressor preventing inconvenience occurring in a terminal part for feeding electricity to an electric element. <P>SOLUTION: The hermetic electric compressor includes a sealed vessel 12 housing the electric element 14 and a rotary compression mechanism part 18 driven by the electric element. CO<SB>2</SB>refrigerant is compressed by the rotary compression mechanism part and is discharged into the sealed vessel. A terminal 20 attached to the sealed vessel, comprises: a circular glass part 20A through which an electric terminal passes so that the electric terminal is attached to the terminal; and a flange-like metallic mounting part 20B formed around the glass part and welded and fixed to the peripheral part of a mounting hole 12D of the sealed vessel. The mounting part has a thickness of a range from 42% to 64% of a plate thickness of the sealed vessel. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a hermetic electric compressor in which an electric element and a compression element driven by the electric element are provided in a hermetic container.

  In a conventional hermetic electric compressor of this type, particularly an internal intermediate pressure type multistage compression rotary compressor, refrigerant gas is drawn into the low pressure chamber side of the cylinder from the suction port of the first rotary compression element, and the operation of the rollers and vanes Is compressed to an intermediate pressure and discharged from the high pressure chamber side of the cylinder into the sealed container through the discharge port and the discharge silencer chamber. The intermediate-pressure refrigerant gas in the sealed container is sucked into the low-pressure chamber side of the cylinder from the suction port of the second rotary compression element, and the second stage compression is performed by the operation of the roller and the vane, so The refrigerant gas flows from the high-pressure chamber side through the discharge port and discharge silencer chamber, flows into the radiator, radiates heat, is throttled by the expansion valve, absorbs heat by the evaporator, and is sucked into the first rotary compression element. repeat.

When a refrigerant having a large high-low pressure difference, for example, carbon dioxide (CO ₂ ) as an example of carbon dioxide gas is used as the refrigerant for the rotary compressor, the refrigerant pressure reaches 12 MPaG in the second rotary compression element having a high pressure, The first rotary compression element on the lower stage side becomes 8 MPaG, which is the pressure in the sealed container.

In such a rotary compressor, a terminal for supplying power to the electric element is attached to the sealed container. FIG. 20 shows a sectional view of the terminal 300 portion of the conventional rotary compressor. The terminal 300 is composed of a circular glass portion 302 provided with an electrical terminal 301 and a metal mounting portion 303 formed around the terminal portion. The mounting portion 303 is formed in a sealed container 304. It was fixed to the peripheral edge of the hole 306 by welding. Such a rotary compressor is disclosed in Patent Document 1, for example.
JP 2001-82368 A

  Here, if the thickness dimension of the attachment portion 303 of the terminal 300 is too thin, the above-described strength (pressure resistance performance) of the refrigerant gas in the sealed container 304 against a high pressure is insufficient, and the attachment portion 303 is cracked. Cause malfunction. On the other hand, if it is too thick, a large amount of heat is required when welding to the sealed container 304, and this heat causes damage to the glass portion 302, resulting in a risk of gas leakage and destruction. was there.

  The present invention has been made to solve the problems of the related art, and provides a hermetic electric compressor capable of avoiding inconveniences occurring in a terminal portion for supplying power to an electric element. For the purpose.

That is, the sealed type electric compressor of the first aspect of the invention, the motor element in a sealed container, and a compression element driven by the electric element, hermetic container and compressing the CO ₂ refrigerant by the compression element The terminal is attached to a sealed container, and the terminal is formed around the glass part with a circular glass part through which the electrical terminal is attached. A flange-shaped metal mounting portion fixed to the peripheral edge of the mounting hole by welding, and the thickness dimension of the mounting portion is in the range of 42% to 64% of the plate thickness of the sealed container. According to a second aspect of the present invention, there is provided a hermetic electric compressor including an electric element in a hermetically sealed container and first and second rotary compression elements driven by the electric element, wherein the first rotary compression element is provided. ejecting in compressed CO ₂ refrigerant gas into the sealed container Further, the discharged intermediate-pressure refrigerant gas is compressed by the second rotary compression element, and includes a terminal attached to the hermetic container, and this terminal has a circular shape through which the electrical terminal is attached. A glass part, and a bowl-shaped metal attachment part formed around the glass part and welded and fixed to the peripheral part of the attachment hole of the sealed container. It is characterized by being in the range of 42% to 64% of the plate thickness.

According to the present invention, it is provided with a terminal attached to a hermetic container of a hermetic electric compressor, and this terminal is formed around a circular glass part through which an electrical terminal is attached, and this glass part, And a flange-shaped metal mounting portion that is welded and fixed to the periphery of the mounting hole of the sealed container, and the thickness dimension of the mounting portion is in the range of 42% to 64% of the plate thickness of the sealed container. Therefore, in a hermetic electric compressor using a CO ₂ refrigerant that increases the pressure in the hermetic container, it is possible to suppress an increase in the amount of heat necessary for fixing the welding while ensuring sufficient pressure resistance of the terminal. It becomes.

  As a result, it is possible to avoid a gas leak or a terminal breakage that occurs when a crack occurs in the terminal mounting portion or the glass portion is damaged.

  Next, embodiments 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) rotary compressor 10 having first and second rotary compression elements 32 and 34 as an embodiment of a hermetic electric compressor of the present invention. 2 is a front view of the rotary compressor 10, FIG. 3 is a side view of the rotary compressor 10, FIG. 4 is another longitudinal sectional view of the rotary compressor 10, and FIG. 5 is yet another longitudinal sectional view of the rotary compressor 10. FIG. Fig. 7 is a plan sectional view of the electric element 14 portion of the rotary compressor 10, and Fig. 7 is an enlarged sectional view of the rotary compression mechanism portion 18 of the rotary compressor 10.

In each figure, reference numeral 10 denotes an internal intermediate pressure multistage compression rotary compressor using carbon dioxide (CO ₂ ) as a refrigerant. The rotary compressor 10 includes a cylindrical sealed container 12 made of a steel plate, and an interior of the sealed container 12. The electric element 14 arranged and housed on the upper side of the space, and the first rotary compression element 32 (first stage) and the second electric element 14 arranged below the electric element 14 and driven by the rotating shaft 16 of the electric element 14. The rotary compression mechanism section 18 is composed of a rotary compression element 34 (second stage). The height dimension of the rotary compressor 10 of the embodiment is 220 mm (outer diameter 120 mm), the height dimension of the electric element 14 is about 80 mm (outer diameter 110 mm), and the height dimension of the rotary compression mechanism 18 is about 70 mm (outer diameter 110 mm). ), The distance between the electric element 14 and the rotary compression mechanism 18 is about 5 mm. The excluded volume of the second rotary compression element 34 is set smaller than the excluded volume of the first rotary compression element 32.

  In the embodiment, the sealed container 12 is made of a steel plate having a thickness of 4.5 mm, the bottom is an oil reservoir, the container body 12A that houses the electric element 14 and the rotary compression mechanism 18, and the upper opening of the container body 12A is closed. And a circular mounting hole 12D is formed in the center of the upper surface of the end cap 12B. The mounting element 12D has a power supply to the electric element 14. A terminal (wiring is omitted) 20 is attached.

    In this case, a stepped portion 12C having a predetermined curvature is annularly formed on the end cap 12B around the terminal 20 in a shape symmetrical with respect to the center axis of the end cap 12B. Further, as shown in FIG. 19, the terminal 20 is formed of a circular glass portion 20A through which an electrical terminal 139 penetrates, and is made of iron (S25C) formed around the glass portion 20A and projecting in a bowl shape obliquely outward and downward. To S45C) and has an axisymmetric shape around the central axis of the end cap 12B. The thickness dimension of the mounting portion 20B is in the range of 2.4 ± 0.5 mm (1.9 mm or more and 2.9 mm or less). And the terminal 20 inserts the glass part 20A into the mounting hole 12D from the lower side and faces the upper side, and attaches the mounting part 20B to the peripheral edge of the mounting hole 12D, and the peripheral edge of the mounting hole 12D of the end cap 12B. The attachment portion 20B is welded to the end cap 12B.

  Here, when the thickness of the mounting portion 20B of the terminal 20 is reduced by using the pressure in the sealed container 12 as an intermediate pressure, which will be described later, the refrigerant in the sealed container 12 becomes less than 1.9 mm in the test. The strength (pressure resistance performance) against the high gas pressure (intermediate pressure) was insufficient, and a crack occurred in the mounting portion 20B itself. On the other hand, when the thickness of the mounting portion 20B is made thicker than 2.9 mm, a large amount of heat is required this time when welding to the sealed container 304, resulting in a test result that may cause adverse effects on the glass portion 20A. .

  In the present invention, based on this, the thickness of the mounting portion 20B of the terminal 20 is set to 2.4 ± 0.5 mm, so that the heat amount necessary for welding and fixing is ensured while sufficiently ensuring the pressure resistance performance of the terminal 20. It was also possible to suppress the increase of.

  The electric element 14 includes a stator 22 attached in an annular shape along the inner peripheral surface of the upper space of the hermetic container 12, and a rotor 24 inserted and arranged with a slight gap inside the stator 22. The rotor 24 is fixed to a rotating shaft 16 that passes through the center and extends in the vertical direction.

  The stator 22 includes a laminated body 26 in which donut-shaped electromagnetic steel plates are laminated, and a stator coil 28 wound around the teeth of the laminated body 26 by a direct winding (concentrated winding) method (FIG. 6). Similarly to the stator 22, the rotor 24 is also formed by a laminated body 30 of electromagnetic steel plates, and a permanent magnet MG is inserted into the laminated body 30.

  An intermediate partition plate 36 is sandwiched 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, a cylinder 38 and a cylinder 40 disposed above and below the intermediate partition plate 36, and the inside of the upper and lower cylinders 38 and 40. The upper and lower rollers 46 and 48 are fitted to the upper and lower eccentric portions 42 and 44 provided on the rotating shaft 16 with a phase difference of 180 degrees and rotate eccentrically, and the upper and lower cylinders 38 are in contact with the upper and lower rollers 46 and 48. , 40 are divided into a low pressure chamber side and a high pressure chamber side, respectively, and upper and lower vanes 50 (lower vanes are not shown), an upper opening surface of the upper cylinder 38 and an opening surface of the lower cylinder 40 below. And an upper support member 54 and a lower support member 56 as support members that also serve as bearings for the rotary shaft 16.

  The upper support member 54 and the lower support member 56 are formed with suction passages 58 and 60 that communicate with the inside of the upper and lower cylinders 38 and 40 through suction ports 161 and 162, and recessed discharge silencer chambers 62 and 64, respectively. The openings of both the discharge silencing chambers 62 and 64 are respectively closed by covers. That is, the discharge silence chamber 62 is closed by an upper cover 66 as a cover, and the discharge silence chamber 64 is closed by a lower cover 68 as a cover.

  In this case, a bearing 54A is erected at the center of the upper support member 54, and a cylindrical bush 122 is mounted on the inner surface of the bearing 54A. Further, a bearing 56A is formed through the center of the lower support member 56, and a cylindrical bush 123 is mounted on the inner surface of the bearing 56A. The bushes 122 and 123 are made of a material having good slidability as will be described later, and the rotating shaft 16 is connected to the bearing 54A of the upper support member 54 and the bearing 56A of the lower support member 56 through the bushes 122 and 123. Retained.

  In this case, the lower cover 68 is made of a donut-shaped circular steel plate, and is fixed to the lower support member 56 from below by main bolts 129... The lower surface opening of the discharge silencing chamber 64 communicating with the inside of the lower cylinder 40 of the compression element 32 is closed. The front ends of the main bolts 129 are screwed into the upper support member 54. The inner peripheral edge of the lower cover 68 protrudes inward from the inner surface of the bearing 56A of the lower support member 56, whereby the lower end surface of the bush 123 is held by the lower cover 68 and is prevented from falling off (FIG. 9). FIG. 10 shows the lower surface of the lower support member 56, and 128 is a discharge valve of the first rotary compression element 32 that opens and closes the discharge port 41 in the discharge silencing chamber 64.

  Here, the lower support member 56 is made of an iron-based sintered material (which may be cast), and the surface (lower surface) on which the lower cover 68 is attached is processed to have a flatness of 0.1 mm or less, Steam processing has been added. Since the surface on which the lower cover 68 is attached by this steam treatment is made of iron oxide, the hole inside the sintered material is blocked and the sealing performance is improved. This eliminates the need for a gasket between the lower cover 68 and the lower support member 56.

  In addition, the electric element 14 side of the upper cover 66 in the discharge silencer chamber 64 and the sealed container 12 is communicated with a communication passage 63 that is a hole penetrating the upper and lower cylinders 38 and 40 and the intermediate partition plate 36 (FIG. 4). ). In this case, an intermediate discharge pipe 121 is erected at the upper end of the communication path 63, and this intermediate discharge pipe 121 is between the adjacent stator coils 28, 28 wound around the stator 22 of the upper electric element 14. It is directed to the gap (FIG. 6).

  Further, the upper cover 66 closes the upper opening of the discharge silencer chamber 62 communicating with the inside of the upper cylinder 38 of the second rotary compression element 34 at the discharge port 39, and the discharge silencer chamber 62 and the electric element inside the sealed container 12. Divide into 14 sides. As shown in FIG. 11, the upper cover 66 has a thickness of 2 mm or more and 10 mm or less (6 mm is the most desirable in the embodiment), and is a substantially donut having a hole through which the bearing 45A of the upper support member 45 passes. In the state in which a gasket 124 with a bead is sandwiched between the upper support member 54 and the upper support member 54, the peripheral portion is surrounded by four main bolts 78. To the upper support member 54. The front ends of the main bolts 78 are screwed into the lower support member 56.

  By setting the upper cover 66 to have such a thickness dimension, it is possible to achieve downsizing and secure an insulation distance from the electric element 14 while sufficiently withstanding the pressure of the discharge silencer chamber 62 that is higher than that in the sealed container 12. You can also do that. Further, an O-ring 126 is provided between the inner peripheral edge of the upper cover 66 and the outer surface of the bearing 54A (FIG. 12). By sealing the bearing 54A side with the O-ring 126, it becomes possible to sufficiently seal the inner periphery of the upper cover 66 and prevent gas leakage, and the volume of the discharge silencer chamber 62 can be increased. The ring eliminates the need to fix the inner peripheral edge of the upper cover 66 to the bearing 54A. Here, in FIG. 11, 127 is a discharge valve of the second rotary compression element 34 that opens and closes the discharge port 39 in the discharge silencer chamber 62.

  Next, in the intermediate partition plate 36 that closes the lower opening surface of the upper cylinder 38 and the upper opening surface of the lower cylinder 40, a position corresponding to the suction side in the upper cylinder 38 is shown in FIGS. 13 and 14. As shown in FIG. 2, a through hole 131 is formed from the outer peripheral surface to the inner peripheral surface, and the outer peripheral surface communicates with the inner peripheral surface to form an oil supply passage. A sealing material on the outer peripheral surface side of the through passage 131 is formed. 132 is press-fitted to seal the opening on the outer peripheral surface side. A communication hole 133 extending upward is formed in the middle of the through hole 131.

  On the other hand, a communication hole 134 communicating with the communication hole 133 of the intermediate partition plate 36 is formed in the suction port 161 (suction side) of the upper cylinder 38. Further, as shown in FIG. 7, a vertical oil hole 80 is formed in the rotating shaft 16 at the center of the shaft, and lateral oil supply holes 82 and 84 (upper and lower eccentric portions 42 and 44) communicating with the oil hole 80 are also formed. The opening on the inner peripheral surface side of the through hole 131 of the intermediate partition plate 36 communicates with the oil hole 80 through these oil supply holes 82 and 84.

  As will be described later, since the inside of the sealed container 12 is at an intermediate pressure, it is difficult to supply oil into the upper cylinder 38, which is at a high pressure in the second stage. The oil that has been pumped up from the oil sump at the inner bottom of the cylinder 12 and moved up through the oil hole 80 enters the through hole 131 of the intermediate partition plate 36 and is sucked into the upper cylinder 38 through the communication holes 133 and 134. To the side (suction port 161).

  In FIG. 16, L indicates the pressure fluctuation on the suction side of the upper cylinder 38, and P1 in the drawing indicates the pressure on the inner peripheral surface of the intermediate partition plate 36. As indicated by L1 in this figure, the suction side pressure (suction pressure) of the upper cylinder 38 is lower than the pressure on the inner peripheral surface side of the intermediate partition plate 36 due to suction pressure loss during the suction process. During this period, oil is supplied from the through hole 131 and the communication hole 133 of the intermediate partition plate 36 to the upper cylinder 38 through the communication hole 134 of the upper cylinder 38.

  As described above, the upper and lower cylinders 38 and 40, the intermediate partition plate 36, the upper and lower support members 54 and 56, and the upper and lower covers 66 and 68 are fastened from above and below by the four main bolts 78. However, the upper and lower cylinders 38, 40, the intermediate partition plate 36, and the upper and lower support members 54, 56 are fastened by auxiliary bolts 136, 136 positioned outside the main bolts 78, 129 (FIG. 4). The auxiliary bolt 136 is inserted from the upper support member 54 side, and the tip thereof is screwed to the lower support member 56.

  The auxiliary bolt 136 is positioned in the vicinity of the guide groove 70 described later of the vane 50 described later. Thus, by adding the auxiliary bolts 136 and 136 and integrating the rotary compression mechanism 18, the sealing performance against the extremely high pressure inside is ensured, and the vicinity of the guide groove 70 of the vane 50. As a result, the back pressure gas leak from the guide groove 70 can be prevented.

  On the other hand, a guide groove 70 for storing the vane 50 described above and a storage portion 70A for storing a spring 76 as a spring member located outside the guide groove 70 are formed in the upper cylinder 38. The portion 70A is open to the guide groove 70 side and the closed container 12 (container body 12A) side (FIG. 8). The spring 76 is in contact with the outer end of the vane 50 and constantly urges the vane 50 toward the roller 46. A metal plug 137 is provided in the housing portion 70A of the spring 76 on the closed container 12 side, and serves to prevent the spring 76 from coming off. A back pressure chamber (not shown) is formed in the guide groove 70, and the discharge pressure (high pressure) of the second rotary compression element 34 is applied to the back pressure chamber. The container 12 side has an intermediate pressure.

  In this case, the outer dimension of the plug 137 is set smaller than the inner dimension of the storage portion 70A, and the plug 137 is inserted into the storage portion 70A by a clearance fit. An O-ring 138 is attached to the peripheral surface of the plug 137 for sealing between the plug 137 and the inner surface of the storage portion 70A. The distance between the outer end of the upper cylinder 38, that is, the outer end of the storage portion 70A, and the container body 12A of the sealed container 12 is smaller than the distance from the O-ring 138 to the end of the plug 137 on the sealed container 12 side. Is set.

  Due to such a dimensional relationship, as in the case where the plug 137 is press-fitted and fixed in the housing portion 70A, the upper cylinder 38 is deformed and the sealing performance with the upper support member 54 is deteriorated, resulting in a deterioration in performance. Can be avoided in advance. Even with such a clearance fit, the distance between the upper cylinder 38 and the sealed container 12 is set to be smaller than the distance from the O-ring 138 to the end of the plug 137 on the sealed container 12 side. Even if it moves in the direction pushed out from the storage portion 70A, the O-ring 138 is still positioned and sealed in the storage portion 70A when the movement is prevented by coming into contact with the hermetic container 12; There is no problem.

  By the way, the connecting portion 90 that connects the upper and lower eccentric portions 42 and 44 formed integrally with the rotating shaft 16 with a phase difference of 180 degrees has a cross-sectional shape that is larger than the circular cross section of the rotating shaft 16. In order to enlarge and give rigidity, it is made into a non-circular shape such as a rugby ball (FIG. 17). That is, the cross-sectional shape of the connecting portion 90 that connects the upper and lower eccentric portions 42 and 44 provided on the rotating shaft 16 is increased in thickness in the direction perpendicular to the eccentric direction of the upper and lower eccentric portions 42 and 44 (hatching in the figure). Part).

  As a result, the cross-sectional area of the connecting portion 90 that connects the upper and lower eccentric portions 42 and 44 provided integrally with the rotating shaft 16 is increased, the second moment is increased, and the strength (rigidity) is increased. Improves sex. In particular, when a refrigerant having a high working pressure is compressed in two stages, the load applied to the rotary shaft 16 increases due to the large pressure difference between the high and low pressures. However, the strength (rigidity) is increased by increasing the cross-sectional area of the connecting portion 90. The rotation shaft 16 is prevented from being elastically deformed.

  In this case, if the center of the upper eccentric portion 42 is O1, and the center of the lower eccentric portion 44 is O2, the center of the arc of the surface of the connecting portion 90 on the eccentric direction side of the eccentric portion 42 is O1, and the eccentric portion 44. The center of the arc of the surface of the connecting portion 90 on the eccentric direction side is O2. Thus, when the rotary shaft 16 is chucked to the cutting machine to cut the upper and lower eccentric portions 42 and 44 and the connecting portion 90, after machining the eccentric portion 42, only the radius is changed and one surface of the connecting portion 90 is changed. It is possible to perform an operation of machining, changing the chuck position, machining the other surface of the connecting portion 90, and machining the eccentric portion 44 by changing only the radius. As a result, the number of times of rechucking the rotating shaft 16 is reduced and the productivity is remarkably improved.

In this case, the carbon dioxide (CO ₂ ) is used as an example of carbon dioxide gas which is a natural refrigerant in consideration of flammability and toxicity as the refrigerant, and the oil as the lubricating oil is, for example, Existing oils such as mineral oil (mineral oil), alkylbenzene oil, ether oil and ester oil are used.

  On the side surface of the container main body 12A of the sealed container 12, the suction passages 58, 60 of the upper support member 54 and the lower support member 56, the upper side of the discharge silencer chamber 62, and the upper cover 66 (position substantially corresponding to the lower end of the electric element 14). The sleeves 141, 142, 143, and 144 are fixed by welding at positions corresponding to. The sleeves 141 and 142 are adjacent to each other vertically, and the sleeve 143 is substantially diagonal to the sleeve 141. Further, the sleeve 144 is located at a position shifted by approximately 90 degrees from the sleeve 141.

  One end of a refrigerant introduction pipe 92 for introducing refrigerant gas into the upper cylinder 38 is inserted and connected into the sleeve 141, and one end of the refrigerant introduction pipe 92 is communicated with the suction passage 58 of the upper cylinder 38. The refrigerant introduction pipe 92 passes through the upper side of the sealed container 12 to reach the sleeve 144, and the other end is inserted and connected into the sleeve 144 to communicate with the sealed container 12.

  Also, 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 is communicated with the suction passage 60 of the lower cylinder 40. The other end of the refrigerant introduction tube 94 is connected to the lower end of the accumulator 146. A refrigerant discharge pipe 96 is inserted and connected into the sleeve 143, and one end of the refrigerant discharge pipe 96 is communicated with the discharge silencer chamber 62.

  The accumulator 146 is a tank that performs gas-liquid separation of the suction refrigerant, and is attached to a bracket 147 on the hermetic container side welded to the upper side surface of the container body 12A of the hermetic container 12 via a bracket 148 on the accumulator side. . The bracket 148 extends upward from the bracket 147 and holds a substantially central portion of the accumulator 146 in the vertical direction. In this state, the accumulator 146 is arranged along the side of the sealed container 12. The refrigerant introduction pipe 92 rises after exiting from the sleeve 141, bent in the right direction in the embodiment, and then rises, and the lower end of the accumulator 146 becomes close to the refrigerant introduction pipe 92. Therefore, the refrigerant introduction pipe 94 descending from the lower end of the accumulator 146 is routed around the left side opposite to the bending direction of the refrigerant introduction pipe 92 when viewed from the sleeve 141 so as to reach the sleeve 142 (FIG. 3). ).

  That is, the refrigerant introduction pipes 92 and 94 respectively communicating with the suction passages 58 and 60 of the upper support member 38 and the lower support member 40 are bent in the opposite direction in the horizontal direction when viewed from the sealed container 12. Thereby, even if the vertical dimension of the accumulator 146 is enlarged to increase the volume, consideration is given so that the refrigerant introduction pipes 92 and 94 do not interfere with each other.

  Further, a flange 151 that can be engaged with a coupler for pipe connection is formed around the outer surfaces of the sleeves 141, 143, and 144, and a thread groove 152 for pipe connection is formed on the inner surface of the sleeve 142. . As a result, the sleeves 141, 143, 144 can be easily connected to the coupler 151 of the test pipe when the airtight test is performed in the completion inspection in the manufacturing process of the rotary compressor 10. It becomes possible to easily screw the test pipe using the screw groove 152. In particular, the sleeves 141 and 142 that are adjacent in the vertical direction are formed with a flange 151 on one sleeve 141 and a thread groove 152 on the other sleeve 142, so that the test pipes can be connected to the sleeves 141 and 142 in a narrow space. Can be connected.

  And the rotary compressor 10 of an Example is used for the refrigerant circuit of the hot-water supply apparatus 153 as shown in FIG. That is, the refrigerant discharge pipe 96 of the rotary compressor 10 is connected to the inlet of the gas cooler 154 for water heating. This gas cooler 154 is provided in a hot water storage tank (not shown) of the hot water supply device 153. The pipe exiting the gas cooler 154 reaches the inlet of the evaporator 157 through an expansion valve 156 as a decompression device, and the outlet of the evaporator 157 is connected to the refrigerant introduction pipe 94. Further, although not shown in FIGS. 2 and 3, a defrost pipe 158 constituting a defrosting circuit branches off from the middle of the refrigerant introduction pipe 92, and the gas cooler 154 is connected via an electromagnetic valve 159 as a flow path control device. It is connected to a refrigerant discharge pipe 96 that reaches the inlet. In FIG. 18, the accumulator 146 is omitted.

  Next, the operation of the above configuration will be described. In the heating operation, the solenoid valve 159 is closed. When the stator coil 28 of the electric element 14 is energized through the terminal 20 and a 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 fitted to the upper and lower eccentric parts 42 and 44 provided integrally with the rotary shaft 16 rotate eccentrically in the upper and lower cylinders 38 and 40.

  As a result, the low-pressure refrigerant (first-stage suction pressure LP: 4 MPaG) is sucked from the suction port 162 to the low-pressure chamber side of the lower cylinder 40 via the refrigerant introduction pipe 94 and the suction passage 60 formed in the lower support member 56. The gas is compressed by the operation of the roller 48 and the vane to become an intermediate pressure (MP1: 8 MPaG), and from the high pressure chamber side of the lower cylinder 40 to the discharge port 41 and the discharge silencer chamber 64 formed in the lower support member 56, through the communication path 63. Then, it is discharged from the intermediate discharge pipe 121 into the sealed container 12.

  At this time, since the intermediate discharge pipe 121 is directed to the gap between the adjacent stator coils 28 and 28 wound around the stator 22 of the upper electric element 14, the refrigerant gas still having a relatively low temperature is supplied to the electric element. It becomes possible to actively supply in the 14 directions, and the temperature rise of the electric element 14 is suppressed. Moreover, the inside of the airtight container 12 becomes intermediate pressure (MP1) by this.

  Then, the intermediate pressure refrigerant gas in the sealed container 12 exits from the sleeve 144 (intermediate discharge pressure is MP1), and the suction port 161 passes through the refrigerant introduction pipe 92 and the suction passage 58 formed in the upper support member 54. To the low pressure chamber side of the upper cylinder 38 (second-stage suction pressure MP2). The suctioned intermediate-pressure refrigerant gas is compressed in the second stage by the operation of the roller 46 and the vane 50 to become a high-temperature and high-pressure refrigerant gas (second-stage discharge pressure HP: 12 MPaG), and is discharged from the high-pressure chamber side. The gas flows into the gas cooler 154 through the discharge silencer chamber 62 formed in the upper support member 54 and 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 dissipates heat to heat the water in the hot water storage tank and generate hot water of about + 90 ° C.

  On the other hand, the refrigerant itself is cooled in the gas cooler 154 and exits the gas cooler 154. Then, after the pressure is reduced by the expansion valve 156, the refrigerant flows into the evaporator 157 to evaporate, and is sucked into the first rotary compression element 32 from the refrigerant introduction pipe 94 through the accumulator 146 (not shown in FIG. 18). repeat.

  In particular, in an environment of low outside air temperature, frost forms on the evaporator 157 by such heating operation. In that case, the electromagnetic valve 159 is opened, the expansion valve 156 is fully opened, and the defrosting operation of the evaporator 157 is executed. As a result, the intermediate-pressure refrigerant in the sealed container 12 (including a small amount of high-pressure refrigerant discharged from the second rotary compression element 34) reaches the gas cooler 154 through the defrost pipe 158. The temperature of this refrigerant is about +50 to + 60 ° C., and the gas cooler 154 does not radiate heat, but initially the refrigerant absorbs heat. Then, the refrigerant discharged from the gas cooler 154 passes through the expansion valve 156 and reaches the evaporator 157. That is, the refrigerant having a relatively high intermediate pressure is supplied directly to the evaporator 157 without being depressurized, whereby the evaporator 157 is heated and defrosted.

  In this way, the intermediate pressure refrigerant gas discharged from the first rotary compression element 32 is taken out from the hermetic container 12 and the evaporator 157 is defrosted, so that it is discharged from the second rotary compression element 34. So as to prevent the reverse phenomenon of the pressure in the discharge (high pressure) and suction (intermediate pressure) of the second rotary compression element 34 that occurs when supplying the high-pressure refrigerant to the evaporator 157 without reducing the pressure. Become.

  Note that the hermetic type electric compressor is not limited to the internal intermediate pressure type multistage compression type rotary compressor as in the embodiment, and the present invention is also effective for a single cylinder rotary compressor and the like. Furthermore, although the rotary compressor 10 was used for the refrigerant circuit of the hot water supply device 153 in the embodiments, the present invention is not limited to this, and the present invention is effective when used for indoor heating.

It is a longitudinal cross-sectional view of the rotary compressor of the Example of the hermetic electric compressor of this invention. It is a front view of the rotary compressor of FIG. It is a side view of the rotary compressor of FIG. It is another longitudinal cross-sectional view of the rotary compressor of FIG. FIG. 3 is still another longitudinal sectional view of the rotary compressor of FIG. 1. It is a plane sectional view of the electric element part of the rotary compressor of FIG. It is an expanded sectional view of the rotary compression mechanism part of the rotary compressor of FIG. It is an expanded sectional view of the vane part of the 2nd rotary compression element of the rotary compressor of FIG. It is sectional drawing of the lower support member and lower cover of the rotary compressor of FIG. It is a bottom view of the lower support member of the rotary compressor of FIG. FIG. 2 is a top view of an upper support member and an upper cover of the rotary compressor in FIG. 1. It is sectional drawing of the upper support member and upper cover of the rotary compressor of FIG. It is a top view of the intermediate partition plate of the rotary compressor of FIG. FIG. 13A is a cross-sectional view taken along line AA. It is a top view of the upper cylinder of the rotary compressor of FIG. It is a figure which shows the pressure fluctuation of the suction side of the upper cylinder of the rotary compressor of FIG. It is sectional drawing for demonstrating the shape of the connection part of the rotating shaft of the rotary compressor of FIG. It is a refrigerant circuit figure of the hot water supply apparatus to which the rotary compressor of FIG. 1 is applied. It is an expanded sectional view of the terminal part of the rotary compressor of FIG. It is an expanded sectional view of the rotary compressor which attached the terminal with a thin attachment part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Rotary compressor 12 Airtight container 12A End cap 12D Mounting hole 14 Electric element 16 Rotating shaft 18 Rotation compression mechanism part 20 Terminal 20A Glass part 20B Attachment part 32 1st rotation compression element 34 2nd rotation compression element 36 Intermediate partition plate 38 , 40 Cylinder 39, 41 Discharge port 42 Eccentric part 44 Eccentric part 46 Roller 48 Roller 50 Vane 54 Upper support member 56 Lower support member 62 Discharge silencer chamber 64 Discharge silencer chamber 66 Upper cover 68 Lower cover 70 Guide groove 70A Storage part 76 Spring (Spring member)
78, 129 Main bolt 90 Connecting portion 92, 94 Refrigerant introduction pipe 96 Refrigerant discharge pipe 131 Through hole (oil supply passage)
132 Sealant 133, 134 Communication hole 137 Plug 138 O-ring 141, 142, 143, 144 Sleeve 146 Accumulator 147, 148 Bracket 151 Hook 153 Hot water supply device 154 Gas cooler 156 Expansion valve 157 Evaporator 158 Defrost tube 159 Solenoid valve

Claims (2)

In a hermetic electric compressor comprising an electric element in a hermetic container and a compression element driven by the electric element, and compressing the CO ₂ refrigerant by the compression element and discharging it into the hermetic container,
Comprising a terminal attached to the sealed container;
The terminal includes a circular glass portion through which an electrical terminal is attached, and a bowl-shaped metal attachment portion formed around the glass portion and welded to the periphery of the attachment hole of the sealed container. Have
A hermetic electric compressor characterized in that a thickness dimension of the mounting portion is in a range of 42% to 64% of a plate thickness of the hermetic container. An electric element and first and second rotary compression elements driven by the electric element are provided in the sealed container, and CO ₂ refrigerant gas compressed by the first rotary compression element is discharged into the sealed container. Further, in the hermetic electric compressor for compressing the discharged intermediate pressure refrigerant gas by the second rotary compression element,
Comprising a terminal attached to the sealed container;
The terminal includes a circular glass portion through which an electrical terminal is attached, and a bowl-shaped metal attachment portion formed around the glass portion and welded to the periphery of the attachment hole of the sealed container. Have
A hermetic electric compressor characterized in that a thickness dimension of the mounting portion is in a range of 42% to 64% of a plate thickness of the hermetic container.