JP5508999B2 - Hermetic scroll compressor - Google Patents

Description

  The present invention relates to a scroll compressor, and more particularly to the overall structure of a scroll compressor for helium for refrigeration and air conditioning.

  As a conventional well-known example in a scroll compressor for helium, as disclosed in Patent Document 1, there is a structural example in which a motor protector serving as a motor protection device is incorporated. Moreover, in the scroll compressor for freezing and air conditioning, as disclosed in Patent Document 2, there is a structural example in which a balance weight is arranged in the motor chamber at the lower part of the frame.

JP 2006-009777 A JP 2009-281165 A

  In patent document 1, since it is set as the position in the vicinity of a discharge pipe so that the cooling effect by the gas flow in a motor chamber can be exhibited, arrangement | positioning of a motor protector can be restrict | limited. For this reason, there are restrictions on the connection work between the neutral point lead wire of the coil end part of the motor and the protector terminal part and the fixing workability of the protector, and there is no flexibility in the coil end forming workability of the motor. The overall cost of work increases.

  In addition, the gas flow velocity around the protector is as low as about 2 to 3 m / S, and there is a limit to the cooling action to the protector by the gas flow, and the current capacity of the motor protector must be increased. There is a problem that it cannot be made.

  Also, the increase in the motor protector body size due to the increase in the motor protector current capacity requires an increase in the motor chamber space and an increase in the height direction. As a result, the overall height of the compressor increases and the overall size of the compressor increases. There is concern about the problem of increasing the weight and weight.

  An object of this invention is to improve the cooling effect of a motor protector.

The object of the present invention is as follows.
In the sealed container, the scroll compressor unit and the electric motor unit are housed, and the scroll compressor unit meshes the fixed scroll and the orbiting scroll with the spiral wrap upright on the disc-shaped end plate with the wraps inside each other, The orbiting scroll is engaged with an eccentric mechanism connected to the rotating shaft, and the orbiting scroll is caused to orbit with respect to the fixed scroll without rotating. The fixed scroll has an outlet opening at the center and an inlet opening at the outer periphery. In a hermetic scroll compressor in which gas is sucked from the suction port, moved around the compression chamber formed by both scrolls to reduce the volume, the gas is compressed, and the compressed gas is discharged from the discharge port.
A function that directly cuts a motor circuit that is energized in the motor coil due to an abnormal increase in motor current and abnormal increase in gas temperature near the outer edge of the balance weight in the motor chamber provided on the rotating shaft at the lower part of the frame. The motor protector means is fixed to the upper part of the motor coil end part in an exposed state via the insulating sheet means, and the balance weight passes through the first weight part passing through the upper side of the motor protector and the inner peripheral side. This is achieved by the hermetic scroll compressor structure characterized in that the flow of fluid is generated on the upper and side surfaces of the motor protector by the rotation of the second weight portion .

The object of the present invention is as follows.
A rotating shaft driven by a motor;
A scroll compressor unit driven by rotation of the rotating shaft;
A balance weight provided on the rotary shaft for canceling an unbalance of the scroll compressor section due to the rotation;
In a hermetic scroll compressor including a motor protector fixed to a motor coil end of the motor,
The motor protector is fixed in a state exposed to the motor coil end,
The balance weight has a first weight part passing through the upper side of the motor protector and a second weight part passing through the inner peripheral side, so that fluid flows to the upper and side surfaces of the motor protector due to its rotation. Ru is generated
It is achieved by closed-type scroll compressor, wherein a call.

The balance weight includes a semi-cylindrical first weight portion and a semi-cylindrical second weight portion having a smaller diameter than the first weight portion. The outer edge dimension R1 of the _first weight portion is equal to that of the upper motor coil end portion. Set R ₁ ≈ (R _m1 + R _m2 ) / 2, which is a substantially intermediate dimension relationship between the outer radius R _m2 and the inner radius R _m2 , or set R ₁ > (R _m1 + R _m2 ) / 2. It is characterized by that.

  Further, the above structure is applied to a sealed scroll compressor for helium having a cooling function by oil injection.

  According to the present invention, the cooling effect of the motor protector can be enhanced.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal sectional view showing an embodiment of the overall structure of a vertical type helium hermetic scroll compressor according to the present invention. Motor stator 3a longitudinal cross-sectional view. The motor stator 3a top view. 4 is an example of a motor circuit diagram around a motor protector 91. FIG. The top view of the balance weight 9. FIG. The longitudinal cross-sectional view of the balance weight 9. FIG. AA sectional drawing of FIG. The longitudinal cross-sectional view of the gas guide passage means 47 periphery part. FIG. 2 is a partial cross-sectional view showing a state in which the balance weight 9 of FIG. 1 is close to a motor protector 91. The compressor top view seen from the top of FIG. The system diagram which shows the whole refrigerating system to which the scroll compressor for helium of this invention is applied.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a longitudinal sectional view showing an embodiment of an oil-filled sealed helium scroll compressor in a vertical structure. FIGS. 2 and 3 are a longitudinal sectional view and a plan view showing a summary of parts in which the motor stator 3a and the motor protector 91 are combined. FIG. 4 is a motor circuit diagram. 5 and 6 are a plan view and a longitudinal sectional view of the balance weight 9.

  The balance weight 9 is for canceling the unbalance of the scroll compressor portion due to the rotation of the shaft, and for canceling the centrifugal force generated by the turning motion of the orbiting scroll 6 and the centrifugal force on the rotor weight 12 side. It is a component and is installed in the lower part of the frame 7 and in the upper part of the motor chamber 1b1.

  The balance weight 9 includes a semi-cylindrical first weight portion 9a and a semi-cylindrical second weight portion 9b having a smaller diameter.

  In FIG. 1, a scroll compressor unit (5, 6) and a motor unit 3 are housed in a sealed container 1, and the scroll compressor unit includes a fixed scroll 5 for erecting a spiral wrap on a disk-shaped end plate. The orbiting scroll 6 is meshed with the laps inside each other, and the orbiting scroll 6 is engaged with an eccentric shaft 14a connected to the rotating shaft 14, and the orbiting scroll 6 is orbited with respect to the fixed scroll 5 without rotating. The scroll 5 is provided with a discharge port 10 opened at the center and a suction port 15 opened at the outer periphery, and gas is sucked from the suction port 15 and moved around a compression chamber 8 formed by both scrolls 5 and 6. The volume is reduced to compress the gas, and the compressed gas is moved from the discharge port 10 to the motor chamber 1b through the communication chamber 18 (18a, 18b) in the container chamber (discharge chamber) 1a and further discharged. Outside device through 20 show the closed-type scroll compressor structure for discharging the gas.

  When the working gas is helium gas, the oil injection pipe 31 for cooling the working helium gas passes through the sealed container 1 and is connected to the oil injection port 22 provided in the end plate portion 5a of the fixed scroll 5. An oil injection mechanism. The injection oil discharged from the discharge port 10 becomes mist-like oil and flows into a mixed fluid with helium gas, and moves from the container chamber 1a to the motor chamber 1b through the communication passage 18 (18a, 18b). Will do.

  As shown in FIGS. 7 and 8, a rectangular gas guide passage means 47 for the mixed fluid is provided on the downstream side of the passage 18 b provided at the outer edge of the frame 7. The gas guide passage means 47 serves as an oil separation mechanism, and an impingement plate portion 47a is provided to change the direction of the vertical flow so that the outlet 47b of the passage means has a horizontal flow. The opening 47b of the gas guide passage means 47 is set so as to face the outer surface portion of the opposing motor coil end portion 3g.

As shown in FIG. 1 and FIG. 7, the motor circuit for energizing the motor coil in the vicinity of the outer edge of the balance weight 9 provided at the lower part of the frame and energizing the motor coil due to the abnormal increase in motor current and abnormal increase in gas temperature is directly provided. securing the motor protector 91 having the function of cutting by a motor coil end portion 3g, tied through the thin-film insulating sheet means 150a in the upper part of 3c string 186.

A motor circuit diagram is shown in FIG. This circuit is equipped with a motor protector 91 at the neutral point 3k of the star connection. Configure the contact portion 91p at two locations on the motor protector 91 (current cutoff unit) for three-phase, by this configuration, the motor circuit allowed to energize the motor coil portion 3e by an abnormal increase in abnormal growth and the gas temperature of the motor current It shows a motor protector 91 having the function of direct cut. For this reason, the contact portion is always closed. It opens at the time of abnormality.

  As shown in FIG. 3, 91a, 91b and 91c are protector pin portions. 3e is a motor coil part. Reference numeral 70a denotes a hermetic terminal. In FIG. 4, as the structure of the contact portions 91p, 91p2, there is a bimetal structure (not shown). The motor protector 91 is an automatic return type in which, when the ambient temperature returns to normal, the contact is closed and current flows again to the circuit by the bimetal structure.

As shown in FIGS. 2 and 5, the outer radial dimension R ₁ of the weight portion 9a of the balance weight 9, the motor coil end portion 3g, outer radius R _{m @ 2} of 3c, the dimensional relationship between the inner radius R _{m @ 2,} R ₁ ≈ (R _m1 + R _m2 ) / 2, that is, the same dimension is set. Alternatively, R ₁ > (R _m1 + R _m2 ) / 2 is set to further induce a turbulent flow.

Further, the R _pu dimension (FIG. 3), which is the center position (diameter dimension position) at which the protector is disposed, is approximately the same as the R ₁ dimension of the outer radius dimension of the weight 9a. Outer radius R ₂ dimensions of the weight portion 9b has an appropriately smaller size than the coil end section inner dimension R _{m @ 2.} By adopting this configuration, the peripheral speed around the weight 9a, which is the outer edge of the balance weight 9, is several tens of meters / second (when the compressor has a diameter of several tens of millimeters and a rotational speed of several thousand revolutions). The gas flow (or a mixture with oil) in the motor chamber 1b1 collides with the balance weight 9 to promote turbulence in the flow, and the ambient conditions of the protector in the turbulent flow region can be made to satisfy the atmospheric conditions. The forced cooling effect on the motor protector 91 by the body can be enhanced. FIG. 7 shows the flow aspect of the turbulent mixture around the balance weight 9.

  In other words, the motor protector 91 is cooled by devising the shape of the balance weight and stirring the periphery of the motor protector 91. The balance weight 9 has a portion that generates a flow in the vicinity of the motor protector (in the embodiment, its upper surface and side surfaces) by its rotation. This is a semi-cylindrical first weight portion 9a and a semi-cylindrical second weight portion 9b having a smaller diameter. A turbulent flow is generated in the sealed container by the portion, and the motor protector 91 is cooled.

  Therefore, in order to arrange the motor protector 91 in the turbulent flow, it is fixed to the upper part of the motor coil end portions 3g and 3c by the tie strap 186. An insulating sheet means 150a is disposed between the motor protector 91 and the motor coil end portions 3g and 3c. By fixing with the binding string 186, the distance between the motor protector 91 and the balance weight 9 can be made as small as possible, and the turbulent flow can be struck against the motor protector 91 as much as possible. Needless to say, if the motor protector 91 is exposed without being covered with a cover or the like, the cooling effect is enhanced.

  In the conventional machine, there is no means for stirring, and the flow velocity around the protector is about several m / second or less. Therefore, in this embodiment, a cooling effect of about ten times can be obtained. In addition, a cooling effect on the upper portions of the motor coil end portions 3g and 3c (forced cooling action by a fluid mixture of oil and gas on the coil end main body) can be obtained, and the motor coil temperature can be lowered.

  As shown in FIG. 7, the motor protector 91 is disposed on the upper surface of the coil end portion at a substantially intermediate position between the gas guide passage means 47 and the discharge pipe 20 for the mixed fluid. It is not necessary to install in the vicinity of the outlet of the discharge pipe 20 of the conventional example, and there are no significant restrictions on the protector arrangement.

  Further, as shown in FIG. 9, a motor protector 91 is disposed above the coil end 3c that is in the vicinity of the outer space of the stepped balance weight 9, and the lower end surface 9k of the second weight portion 9b is the rotor end ring 3j. In this structure, the balance weight 9 is reduced in size and size, and the space (the motor chamber 1b1) is saved.

  As shown in FIGS. 1 to 3 and FIGS. 7 and 9, the motor protector 91 has a main body outer surface as a charge exposed portion, and as described above, above the lower end surface of the motor protector 91 and the motor coil end portion. The end surface portion is fixed by a tie strap 186 (186a, 186b) only through a thin-film insulating sheet means 150a, and is fixed in a so-called naked state. The insulating sheet means 150a includes a polyester-based synthetic resin material (sheet material) that is relatively soft and heat resistant.

  With this configuration, the forced cooling function by the gas flow flowing around the motor protector 91 or the mixed fluid with oil can be greatly improved. Therefore, the MCC value in the overload condition that becomes the maximum operating current value of the motor protector can be set. It can be further increased. Further, it is possible to further extend the life of the protector contact portion 91p serving as an overcurrent interruption portion. Reference numeral 11 denotes a cylindrical collar member that determines axial positions of the balance weight 9 and the motor rotor 3b. As described above, in the present embodiment, the shape of the balance weight 9, the dimensions of the coil end portion, and the motor protector arrangement are specified, and a three-way relationship is set. Reference numeral 61 denotes an auxiliary frame, and reference numeral 64 denotes an auxiliary bearing.

As shown in FIG. 1, the suction pipe 17 and the oil injection pipe 31 in the upper part of the compressor have an elbow structure, and the heights of both are approximately L _s = L _m . For this purpose, the suction pipe size is made smaller than the discharge pipe size. For example, the suction pipe size is 5/8 inch and the discharge pipe size is 3/4 inch. On the other hand, the size of the oil injection pipe 31 is ½ inch. That is, the suction pipe and the oil injection pipe at the top of the compressor have an elbow structure, and the suction pipe size and the oil injection pipe position height are reduced by about 15% smaller than the discharge pipe size (outer diameter). Are almost the same height.

  By adopting this configuration, the overall height of the helium hermetic scroll compressor can be set low. For this reason, a ripple effect is obtained also in the size reduction and weight reduction of a compressor unit. In a normal air-conditioning compressor, the suction pipe size is 50% larger than the outer diameter size that is two to three ranks larger than the discharge pipe size. Such a structure is unique to the helium compressor.

  Here, taking the helium scroll compressor of FIG. 1 as an example, the flow of working helium gas and the flow of injected cooling oil will be described. In FIG. 1, an oil injection pipe 31 for cooling helium gas passes through the upper lid 2 a of the sealed container 1 and is connected to an oil injection port 22 provided on the end plate part 5 a of the fixed scroll 5. The opening portion of the orbiting scroll 6 is opened to face the tooth tip surface of the wrap 6b of the orbiting scroll 6.

  The scroll compression mechanism part is accommodated in the upper part which becomes the suction pipe 17 side in the airtight container 1, and the motor part 3 is accommodated in the lower part. The sealed container 1 is partitioned into a motor chamber 1b with the discharge chamber 1a and the frame 7 interposed therebetween. The scroll compression mechanism unit forms a compression chamber (sealed space) 8 by meshing the fixed scroll 5 and the orbiting scroll 6 with each other. The fixed scroll 5 is composed of a disc-shaped end plate 5a and a wrap 5b formed in an upright involute curve or an approximate curve thereto, and has a discharge port 10 at the center and a suction port 15 at the outer periphery. I have. The orbiting scroll 6 is also composed of a disc-shaped end plate 6a, a wrap 6b standing upright and formed in the same shape as the fixed scroll wrap, and a boss portion 6c formed on the anti-wrap surface of the end plate.

  The frame 7 forms a main bearing 40 at the center, and the rotating shaft 14 is supported by the bearing portion. The eccentric shaft 14a at the tip of the rotating shaft is inserted into the boss portion 6c so as to be capable of turning. The fixed scroll 5 is fixed to the frame 7 by a plurality of bolts. The orbiting scroll 6 is supported on the frame 7 by an Oldham mechanism 38 including an Oldham ring and Oldham key. The orbiting scroll 6 does not rotate with respect to the fixed scroll 5. It is formed to make a swivel motion. A motor shaft 14b is integrally connected to the rotating shaft 14, and the motor unit 3 is directly connected thereto. A suction pipe 17 is connected to the suction port 15 of the fixed scroll 5 through the upper lid 2 a of the sealed container 1, and the discharge chamber 1 a in which the discharge port 10 is open passes through the passages 18 a and 18 b at the outer edge of the frame 7. Via the motor chamber 1b (1b1, 1b2).

  The motor chamber 1b communicates with a discharge pipe 20 that penetrates the casing portion 2b at the center of the sealed container. The discharge pipe 20 is installed at a position almost opposite to the positions of the passages 18a and 18b. The motor chamber 1b is divided into an upper space (motor chamber 1b1) of the motor stator 3a and a lower space (motor chamber 1b2) of the motor stator 3a. Arc-shaped passages 25 (25a, 25b, 25c) serving as oil and gas flow paths between the motor stator 3a and the casing 2b inner wall surface 2m so as to communicate the spaces (1b1, 1b2) on both sides. 25d, see FIGS. 3 and 7). Further, the gap 26 of the motor air gap also serves as a passage, and the space (the motor chamber 1b1) and the space (the motor chamber 1b2) communicate with each other through the gap 26.

  According to the flow of the gas and oil mixture in the motor chambers 1b1 and 1b2 inside the container, the motor is directly cooled to the motor by the relatively low-temperature injection oil of 60 ° C. to 70 ° C. and the motor protector having the configuration of the present embodiment. 91 Direct cooling to the main body and the peripheral portion is possible. In the space (motor chamber 1b1), the oil in the gas is separated from the gas and flows downward while cooling the surrounding members 3a, 3h, 3g, 2b, 7, and 14 via the passage 25.

3f is a semicircular arc groove portion through which the discharge pipe 74 is passed. The O _f is a motor central axis. An O-ring 53 is provided between the suction pipe 17 and the fixed scroll 5 to seal the high pressure part and the low pressure part. Further, a space 36 (hereinafter referred to as a back pressure chamber) surrounded by the scroll compressor unit 2 and the frame 7 is formed on the back surface of the end plate of the orbiting scroll 6. An intermediate pressure Pb between the suction pressure and the discharge pressure is introduced through the bored hole 6d (see FIG. 1), and an axial application force that presses the orbiting scroll 6 against the fixed scroll 5 is given.

  The lubricating oil 23 is stored at the bottom of the hermetic container 1, and the lubricating oil 23 is sucked up to the oil suction pipe 27 by the centrifugal pump effect by the eccentric hole 13 provided in the rotating shafts 14 a and 14 b and the rotating shaft 14. It flows through and is supplied to the slewing bearing 32. The oil supplied to and discharged from the slewing bearing 32 falls to the main bearing 40 of the roller bearing, moves to the lower end of the frame, is guided to the discharge pipe 74, and returns to the oil reservoir in the bottom chamber. .

  On the other hand, the oil supplied to and discharged from the slewing bearing 32 moves to the back pressure chamber 36 through the sealing means 85 having an annular seal ring structure. The oil that has moved to the back pressure chamber 36 is injected into the compression chamber 8 of the scroll wrap through the hole 6d, mixed with the compressed gas, and then discharged into the discharge chamber 1a together with the helium gas. An oil take-out pipe 30 for taking out the lubricating oil 23 at the bottom is provided at the bottom of the closed container 1.

  FIG. 11 shows an embodiment of the scroll compressor unit device 800 for helium and the helium refrigerating device. As shown in FIG. 11, the lubricating oil 23 stored at the bottom of the sealed container 1 is a pressure between the pressure in the sealed container 1 (discharge pressure Pd) and the pressure in the compression chamber 8 (the pressure between the discharge pressure and the suction pressure). ) Flows into the oil take-out pipe 30 from the inflow portion 30a of the oil take-out pipe 30. The oil that has flowed into the oil take-out pipe 30 reaches the oil cooler 33 through the external oil pipe 51 and is appropriately cooled here, and then is passed through the oil injection pipe 31 and the port 22 via the oil pipes 36a and 36b. The pressure is introduced and injected into the compression chamber 8. Reference numeral 271 denotes an oil flow rate adjusting valve. The oil injected into the compression chamber 8 in this manner serves to cool the working gas in the compression chamber 8 and lubricate sliding portions such as the scroll wrap tip.

  The helium gas discharged from the discharge pipe 20 passes through the gas cooler 710 and reaches the oil separator 700, where oil is separated, then reaches the oil adsorber 812, moves to the pipe 720, and then the helium gas A helium refrigerator 860 adiabatically expands, generates a cold heat source, and obtains a cryogenic temperature. After that, it again passes through the pipe 730 and the surge tank 732, passes through the suction pipe 736, and returns to the compressor 100 as normal temperature suction gas. The oil pipe 740 connects the oil separator 700 and the suction pipe 736 and returns the separated oil to the compressor suction side. In addition, this structure can obtain the same operation and effect as the above-described closed scroll compressor for helium even in an air-conditioning / refrigeration hermetic scroll compressor not provided with an oil injection structure.

  According to the above embodiment, the cooling effect of the motor protector can be enhanced. As a result, the motor protector itself can be downsized, and the compressor can be downsized. A small hermetic scroll compressor can be provided.

  More specifically, it is as follows.

  Since the flow rate of the mixture of the gas flow around the balance weight and the oil mist is several tens m / s or more (for example, 40 to), the effect of forced cooling of the entire motor protector by this high flow rate can be maximized. . The maximum cooling current value (MCC value) of the motor protector can be further increased by greatly improving the forced cooling function by the turbulent gas flow flowing around the protector or the mixed fluid with oil. That is, the upper limit of the operating current of the protector can be increased, and the protector can be downsized.

  Further, since the gas flow velocity around the balance weight is high and almost uniform, there is no restriction on the arrangement of the motor protector, and the mounting property is improved. In addition to the above effects, the space in the motor chamber can be narrowed, so that the height dimension of the compressor can be set low, which has the effect of reducing the size of the compressor.

  In addition, by inducing the flow of the high-speed mixture, not only the cooling effect of the protector body but also the forced cooling effect to the upper part of the surrounding coil ends can be generated, so that the effect of lowering the coil temperature can be exhibited and the length of the motor itself can be increased. Life expectancy can be improved.

  In particular, in the scroll compressor for helium, since the suction pipe and the oil injection pipe at the height of the compressor have an elbow structure, and the height of both is almost the same, the compact compressor structure with a low height Thus, the compressor unit can be reduced in size and weight. As a result, cost reduction can be realized.

DESCRIPTION OF SYMBOLS 1 Airtight container 1b, 1b1, 1b2 Motor chamber 3 Motor part 3a Motor stator 3b Motor rotor 3h, 3g Motor coil end part 5 Fixed scroll 6 Orbiting scroll 7 Frame 8 Compression chamber 9 Balance weight 10 Discharge port 14 Rotating shaft 14a Eccentric shaft 15 Suction Port 17 Suction pipe 18a, 18b, 25 Passage 20 Discharge pipe 22 Port 23 Lubricating oil 30 Oil take-out pipe 31 Oil injection pipe 32 Swivel bearing 38 Oldham mechanism 40 Main bearing 47 Gas guide passage means 91 Motor protector 150a Insulating sheet means 186 Tie string

Claims (6)

In the sealed container, the scroll compressor unit and the electric motor unit are housed, and the scroll compressor unit meshes the fixed scroll and the orbiting scroll with the spiral wrap upright on the disc-shaped end plate with the wraps inside each other, The orbiting scroll is engaged with an eccentric mechanism connected to the rotating shaft, and the orbiting scroll is caused to orbit with respect to the fixed scroll without rotating. The fixed scroll has an outlet opening at the center and an inlet opening at the outer periphery. In a hermetic scroll compressor in which gas is sucked from the suction port, moved around the compression chamber formed by both scrolls to reduce the volume, the gas is compressed, and the compressed gas is discharged from the discharge port. there a frame lower part the outer edge near the balance weight of the motor chamber provided in the rotary shaft, the abnormal increase in abnormal growth and the gas temperature of the motor current The motor protector means having a function of directly cutting a motor circuit allowed to energize the motor coil is fixed in a state of being exposed through the insulating sheet means in the upper part of the motor coil end portion by the balance weight, of said motor protector means By having a first weight part passing through the upper side and a second weight part passing through the inner peripheral side, a fluid flow is generated on the upper and side surfaces of the motor protector means by rotation thereof. Hermetic scroll compressor. A rotating shaft driven by a motor;
A scroll compressor unit driven by rotation of the rotating shaft;
A balance weight provided on the rotary shaft for canceling an unbalance of the scroll compressor section due to the rotation;
In a hermetic scroll compressor including a motor protector fixed to a motor coil end of the motor,
The motor protector is fixed in a state exposed to the motor coil end,
The balance weight has a first weight part passing through the upper side of the motor protector and a second weight part passing through the inner peripheral side, so that fluid flows to the upper and side surfaces of the motor protector due to its rotation. Ru is generated
Hermetic scroll compressor, wherein a call. The balance weight according to claim 1 or 2 , comprising the first weight portion formed in a semi-cylindrical shape and the second weight portion formed in a semi-cylindrical shape having a smaller diameter than the first weight portion. The outer edge portion dimension R1 is set to R1≈ (Rm1 + Rm2) / 2, which is a substantially intermediate dimension relationship between the outer radius Rm2 and the inner radius Rm2 of the upper motor coil end, or R1> (Rm1 + Rm2) / hermetic scroll compressor according to claim 1, wherein a setting of 2. The working gas is helium gas, and the scroll compressor unit and the motor unit are housed in a sealed container, and the scroll compressor unit includes a fixed scroll and an orbiting scroll for standing a spiral wrap on a disk-shaped end plate. The wraps are meshed with each other, engaged with an eccentric mechanism that connects the orbiting scroll to the rotating shaft, and the orbiting scroll is orbited with respect to the fixed scroll without rotating. And a suction port that opens to the outer periphery, sucks gas from the suction port, moves around the compression chamber formed by both scrolls to reduce the volume, compresses the gas, and discharges the compressed gas from the discharge port Then, an oil injection pipe for cooling the working helium gas is passed through the sealed container and connected to the oil injection port provided in the end plate portion of the fixed scroll It was in the oil injection mechanism portion helium enclosed scroll compressor provided with, in the outer vicinity of the balance weight of the motor chamber provided in the rotary shaft to a frame lower portion, abnormal increase and the gas temperature of the motor current A motor protector means having a function of directly cutting a motor circuit that energizes the motor coil due to an abnormal increase of the motor coil is fixed in an exposed state via an insulating sheet means above the motor coil end part, and the balance weight is fixed to the motor By having the first weight part passing through the upper side of the protector means and the second weight part passing through the inner peripheral side, fluid flow is generated on the upper and side surfaces of the motor protector means by rotation thereof. Features a sealed scroll compressor for helium. In claim 3 stepped balance weight according of the second 請 Motomeko 3 wherein the lower end surface of the weight portion you characterized in that it is set to extend in the axial direction so as to face the rotor end ring top surface Hermetic scroll compressor.   The suction pipe and oil injection pipe at the top of the compressor have an elbow structure, and the suction pipe size is made smaller than the discharge pipe size so that the suction pipe position height and the oil injection pipe position height are almost the same height. The hermetic scroll compressor according to claim 1 or 4.

Images