JP5827147B2 - Screw compressor - Google Patents

Description

  The present invention relates to a hermetic screw compressor used for a refrigerator, an air conditioner, and the like, and more particularly, to a screw compressor in which a motor is cooled by suction gas.

  In the screw compressor, as a means for increasing the cooling efficiency of the motor, a technique for adjusting the cross-sectional area of the gas passage around the motor stator to increase the flow rate of the suction gas is described (see Patent Document 1 and Patent Document 2). In addition, a technique of providing a liquid refrigerant introduction means in the intake gas introduction portion of the casing is described (see Patent Document 3).

JP 58-32990 A JP-A-1-237389 JP 2000-320907 A

  However, in the prior art described in Patent Literature 1 to Patent Literature 3, most of the suction gas flows in a concentrated manner in a gas passage having a small resistance, that is, a large cross-sectional area, and thus it is difficult to flow the suction gas uniformly. This was a cause of local temperature rise of the motor coil. In particular, as in Patent Documents 1 to 3, when the suction port to the screw rotor is located below the motor shaft center, the temperature of the motor coil above the shaft center rises. This is because the gas passage around the motor stator located below the shaft center is close to the suction port, and the flow path length from the suction gas introduction part (suction port) formed in the casing is shorter than the upper side of the shaft center. This is because the intake gas easily flows. In addition, since a space for connecting the motor power line to the power supply terminal outside the screw compressor is required above the motor shaft center, the suction gas stays in this space and effective cooling of the motor coil is achieved. There is a problem that can not be.

  An object of the present invention is to provide a screw compressor capable of uniformly cooling a motor coil with a simple structure.

The present invention includes a pair of male and female screw rotors that are parallel to each other and mesh with each other, a motor that drives the screw rotor, the screw rotor and the motor, and the motor for the gas flow. A hermetically sealed casing disposed upstream of the screw rotor, wherein the casing has a gas suction passage to the screw rotor, the coil end being below the axial center of the coil end protruding in the axial direction of the motor. thereby formed so as to open along the, the gas passage of the outer periphery of the motor stator of the motor is formed only above the said axis center, immediately after the coil end on the downstream side of the front SL motor and the gas the top of the suction passage, toward the gas passing through the gas passage from the top to the bottom along the outer circumferential surface of the coil end Characterized in that a gas collision member to flow through.

  According to this, the gas sucked into the casing passes above the shaft center on the outer periphery of the motor stator by the gas passage on the outer periphery of the motor stator formed above the shaft center. In addition, since the gas collision member is formed immediately after the coil end on the downstream side and in the upper part of the gas suction passage, the gas that has exited from the gas passage and collided with the gas collision part flows from the upper part to the lower part of the coil end. The entire coil end can be cooled.

  ADVANTAGE OF THE INVENTION According to this invention, the screw compressor which can cool a motor coil uniformly with a simple structure can be provided.

It is a longitudinal section showing a screw compressor concerning this embodiment. It is AA sectional drawing of FIG. It is a horizontal sectional view showing arrangement of a screw rotor. It is a top view when a gas suction passage is seen from the motor side. It is a perspective view when a gas suction passage is seen from the motor side. It is a figure which shows the effect of the screw compressor which concerns on this embodiment. It is a longitudinal cross-sectional view which shows the screw compressor which concerns on another embodiment.

  Hereinafter, the screw compressor 100 according to the present embodiment will be described with reference to the drawings. In the embodiment described below, a twin screw compressor will be described, but the present invention is not necessarily limited to the twin screw type, and can be applied to a single screw type. Moreover, as long as it is a hermetic screw compressor, it is not limited to a semi-hermetic one, and may be applied to a fully hermetic one.

FIG. 1 is a longitudinal sectional view showing a screw compressor according to this embodiment.
As shown in FIG. 1, the screw compressor 100 includes a motor unit 1, a compressor unit 2, and a capacity control mechanism unit 3.

  The motor unit 1 is configured by housing a driving motor 7 including a motor stator (stator) 5 and a motor rotor (rotor) 6 in a motor casing 8 (casing). The motor casing 8 has a substantially cylindrical shape and has a storage space S in which the drive motor 7 is stored sideways. Further, the motor casing 8 is formed with a suction port 4 into which refrigerant gas (gas) is introduced at one end in the axial direction of the drive motor 7, and a strainer 4 a for collecting foreign matter is attached to the discharge portion of the suction port 4. It has been. The drive motor 7 is constituted by, for example, a three-phase brushless DC motor.

  The motor stator 5 includes a stator iron core and a stator winding. The stator iron core is configured by, for example, laminating a plurality of electromagnetic steel plates formed in a substantially annular shape in the axial direction, and is configured by providing a stator winding on a tooth portion protruding radially inward (rotor side). ing. The wire of the stator winding is composed of, for example, a copper conductor and an insulating coating layer that covers the outer periphery of the conductor and insulates the conductor.

  The motor stator 5 has coil ends 5a and 5b at both ends of the stator core in the axial direction, and the stator winding protrudes on both sides in the axial direction. The coil ends 5a and 5b have a substantially ring shape (substantially cylindrical shape), and a part (tip) of the strainer 4a is inserted into the space inside the upstream coil end 5a, and the downstream coil end 5b. A part of a cylindrical portion 9a, which will be described later, is inserted into the inner space. The coil end 5b on the downstream side with respect to the flow of the refrigerant gas corresponds to a “coil end” recited in the claims.

  The motor rotor 6 is configured by, for example, laminating a plurality of electromagnetic steel plates formed in a substantially annular shape in the axial direction, and a shaft G1 extending from a male rotor 10A (screw rotor), which will be described later, is inserted into a through hole at the center of the shaft. It is fixed to the motor rotor 6 with bolts or the like. Therefore, when the motor rotor 6 is rotated, the male rotor 10A is rotated via the axis G1. In FIG. 1 and FIG. 3, the helical gear of the male rotor 10A is not shown.

  As shown in FIG. 2, the motor unit 1 has a gas extending in the axial direction of the driving motor 7 on the outer periphery of the motor stator 5 by the outer peripheral surface 5 d of the motor stator 5 and the inner peripheral surface 8 a of the motor casing 8. A passage 20 is formed. That is, concave notches 8a1, 8a2, 8a3 that are elongated in the circumferential direction are formed on the inner peripheral surface 8a of the motor casing 8 at intervals, and the notches 8a1, 8a2, 8a3, and the motor A gas passage 20 is constituted by the outer peripheral surface 5 d of the stator 5. The gas passage 20 is located above the axial center O of the drive motor 7 (coil end 5b (see FIG. 1)).

  In this embodiment, the case where the three gas passages 20 are provided has been described as an example. However, the present invention is not limited to this, and the gas passage 20 is located above the axial center O. If there are two or less gas passages 20 or four or more gas passages 20, the pressure can be appropriately set within a range in which the pressure loss of the refrigerant gas does not become excessive. In the present embodiment, the circumferential lengths (widths) of the gas passages 20 need not be set to the same length, and may be different from each other.

  Further, an air gap (gap) 21 is formed between the motor stator 5 and the motor rotor 6, and the refrigerant gas introduced from the suction port 4 moves the air gap 21 through the shaft of the drive motor 7. By passing in the direction (see FIG. 1), the stator winding (motor coil) provided inside the stator core is cooled. As for the motor coil of the upstream coil end 5a (see FIG. 1), the entire coil end 5a is cooled by the refrigerant gas introduced from the suction port 4.

  Returning to FIG. 1, a terminal box 50a is provided at the top of the motor casing 8, and a power terminal 50b provided in the terminal box 50a and an electric wire (power line) 5c extending from the coil end 5b are connected. Yes.

  The compressor unit 2 includes a main casing 9 (casing), a screw rotor 10, roller bearings 11a and 11b, a ball bearing 12, a discharge casing 13 (casing), an oil separator 14, a gas collision member 18, and the like. The main casing 9 and the discharge casing 13 are fixed together with the motor casing 8 with a bolt or the like so as to be in a sealing relationship with each other.

  The main casing 9 includes a cylindrical bore 16a and a gas suction passage R for introducing refrigerant gas into the cylindrical bore 16a. The gas suction passage R is formed to open along the coil end 5b below the axial center O of the coil end 5b.

  The cylindrical bore 16a of the main casing 9 is formed with a cylindrical portion 9a through which a shaft G1 extending from the screw rotor 10 (male rotor 10A) is inserted. Inside the cylindrical portion 9a, a roller bearing 11a (low-pressure side bearing) that rotatably supports the shaft G1 is provided. Further, a part (tip) of the cylindrical portion 9a is inserted into a space inside the coil end 5b.

  Further, the main casing 9 is formed with a discharge port 24 which is a refrigerant gas discharge passage from the screw rotor 10. The discharge port 24 is configured to communicate with the oil separator 14 via a discharge passage (not shown). The oil separator 14 has an oil separation space 14a (see FIG. 3) in the upper part in the vertical direction, an oil sump space 14b in the lower part, and is configured integrally with the main casing 9.

  The discharge casing 13 includes a roller bearing 11b (high-pressure side bearing) and a ball bearing 12 (high-pressure side bearing) that rotatably support a shaft G1 extending from the screw rotor 10 (male rotor 10A) to the side opposite to the driving motor 7. Is stored. The discharge casing 13 is provided with a shielding plate 13a at one end in the axial direction for closing the bearing chamber that houses the roller bearing 11b and the ball bearing 12.

  The gas collision member 18 is formed of a plate-like member, and is fixed to the main casing 9 via a bolt B immediately after the coil end 5b. It should be noted that the distance between the gas collision member 18 and the coil end 5b can be set as appropriate within a range in which the entire coil end 5b can be cooled in the description of operations described later. The detailed shape and position of the gas collision member 18 will be described later.

  The capacity control mechanism unit 3 includes a slide valve 26, a rod 27, a hydraulic piston 28, and a coil spring 29. The rod 27, the hydraulic piston 28 and the coil spring 29 are accommodated in the discharge casing 13. In FIG. 1, illustration of an electromagnetic valve and a hydraulic flow path for operating the hydraulic piston 28 is omitted.

  The slide valve 26 is for bypassing a part of the refrigerant gas sucked into the meshing portion of the screw rotor 10 to the suction side by the bypass passage 26a and controlling the capacity, and extends in the axial direction (left-right direction in the drawing). The recess 9b is movably accommodated.

  The hydraulic piston 28 drives the slide valve 26 in the axial direction (left-right direction in the figure) via the rod 27 and is slidably accommodated in a cylinder chamber 30 extending in the left-right direction (axial direction). The coil spring 29 is disposed in the cylinder chamber 30 and applies a force that always presses the hydraulic piston 28 toward the anti-slide valve 26 side (right direction in the drawing).

  As shown in FIG. 3, in the cylindrical bore 16a of the main casing 9, the axis G1 of the male rotor 10A (10) and the axis G2 of the female rotor 10B (10) are respectively arranged in parallel, and the male rotor 10A and the female rotor 10B is stored so as to mesh with each other.

  The shaft G2 of the female rotor 10B is rotatably supported by the roller bearing 11a in the main casing 9, and is rotatably supported by the roller bearing 11b and the ball bearing 12 in the discharge casing 13.

  Of the compression reaction forces acting on the male and female screw rotors 10 during compression, the radial load is supported by the roller bearings 11 a and 11 b, and the thrust load is supported by the ball bearing 12.

  Further, the shaft G1 of the male rotor 10A is directly connected to the drive motor 7 on the low pressure side. In the present embodiment, the male rotor 10A and the female rotor 10B constitute a pair of male and female screw rotors 10.

  Further, the screw compressor 100 is connected to the main casing 9 and the discharge casing 13 through an oil supply passage (not shown) that communicates the oil sump space 14b (see FIG. 1) of the oil separator 14 with the bearings 11a, 11b, and 12. Is formed. For example, the oil after lubricating the suction side roller bearing 11a is discharged to the drive motor 7 (coil end 5b) side, and the oil after lubricating the discharge side roller bearing 11b and the ball bearing 12 is discharged from the discharge casing. An oil discharge passage (not shown) formed in 13 is discharged into a sealed space of the meshing portion of the screw rotor 10.

  As shown in FIG. 4, the gas collision member 18 is disposed immediately after the coil end 5 b (see FIG. 1) as described above, and above the gas suction passage R (gas suction passage) of the main casing 9. Has been placed.

  That is, the gas collision member 18 has a substantially trapezoidal shape, and a semicircular cutout portion 18 a is formed so that a lower portion thereof straddles the cylindrical portion 9 a of the main casing 9. Further, the side edge portions 18b and 18c of the gas collision member 18 have a shape along the side inner walls 9c and 9d of the main casing 9, and the upper edge portion 18d of the gas collision member 18 extends to the vicinity of the upper inner wall 9e. Is formed. The upper inner wall 9e is formed such that the height in the vertical direction increases toward the opening side (see FIG. 1). Further, the lower edge portions 18e and 18f formed in a bifurcated manner of the gas collision member 18 are positioned at a height in the vicinity of the shaft center O, in other words, are positioned at the upper portion of the gas suction passage R. .

  Further, bolt insertion holes 18g, 18h are formed in the gas collision member 18, and bolts B (see FIG. 1, only one is shown) are inserted into these bolt insertion holes 18g, 18h, and fastened to the wall surface of the main casing 9. Thus, the gas collision member 18 is fixed to the main casing 9. The fixing of the gas collision member 18 to the main casing 9 is not limited to bolt fixing, and may be attached using other fixing means such as welding or press fitting. Further, the fixing position of the bolt is not limited to this embodiment.

  Further, a gas suction passage R is formed in the main casing 9 below the gas collision member 18. The gas suction passage R extends from the opening edge portion 9f of the main casing 9 to the lower portion of the screw rotor 10 (see FIGS. 1 and 3) on the axially inner side of the cylindrical portion 9a. In FIG. 4, a portion indicated by a solid line in the reference numeral 16 b indicates a suction port located on the innermost side in the axial direction of the gas suction passage R.

  As shown in FIG. 5, the main casing 9 has an outer peripheral inner wall surface 23 in which the bottom surface of the gas suction passage R facing the outer peripheral surface of the coil end 5b is formed in a substantially semi-conical shape. That is, the outer peripheral inner wall surface 23 has a shape along a substantially semi-conical slope obtained by cutting the truncated cone so as to pass through the approximate center of the shaft, and from the opening edge 9f of the main casing 9 to the suction port 16b. It has the inclined surface 23a which rises linearly toward (see FIG. 1). Thereby, the outer peripheral inner wall surface 23 is configured such that the flow passage cross-sectional area of the opening edge portion 9f of the main casing 9 is the largest, and the flow passage cross-sectional area gradually decreases toward the suction port 16b. The outer peripheral inner wall surface 23 includes a linear inclined surface 23a that rises at a predetermined inclination angle from a position facing the lower portion 5b1 (see FIG. 1) of the coil end 5b (see FIG. 1) to a position of the suction port 16b. This means a shape that does not have a recess at a position facing the lower portion of the coil end, as in a conventional screw compressor.

  Next, the flow of the refrigerant gas in the screw compressor 100 will be described with reference mainly to FIG. 1 and FIG. In FIG. 1, the flow of the refrigerant gas from the suction port 4 to the discharge port 24 is indicated by a white arrow. It should be noted that illustration of the flow of the refrigerant gas from the discharge port 24 to the oil separator 14 with an arrow is omitted.

  That is, the low-temperature and low-pressure refrigerant gas sucked from the suction port 4 provided in the motor casing 8 passes through the gas passage 20 formed between the driving motor 7 and the motor casing 8, and then the coil end 5b. It collides with the gas collision member 18 provided immediately after the and flows from the upper part to the lower part of the coil end 5b. That is, the refrigerant gas that has collided with the gas collision member 18 flows from the top to the bottom along the outer peripheral surface of the coil end 5b, and the cylindrical portion 9a is inserted into the coil end 5b. (Refer to FIG. 1) The refrigerant gas that has collided with the gas collision member 18 flows from the upper part toward the lower part between the inner peripheral surface 5b2 of the coil end 5b and the cylindrical part 9a. Thus, the whole including the outer peripheral surface and inner peripheral surface of the coil end 5b can be cooled. Then, the refrigerant flowing from the upper part to the lower part of the coil end 5b collides with the outer peripheral inner wall surface 23 having a substantially semi-conical shape.

  As for the cooling of the motor coils other than the cooling of the motor coil of the coil end 5b, the motor gas except the coil ends 5a and 5b of the driving motor 7 is cooled by the refrigerant gas passing through the air gap 21. Further, when the refrigerant gas is introduced from the suction port 4, the entire upstream coil end 5a is cooled.

  Further, as described above, since the coil end 5b can be cooled from the upper part to the lower part, the electric wire (power line) 5c of the drive motor 7 is connected to the power supply terminal 50b outside the screw compressor 100. Even when the space Q for connection is formed, there is no problem that the motor coil cannot be cooled effectively.

  Incidentally, in this embodiment, since the gas passage 20 is provided above the shaft center O of the driving motor 7 (see FIG. 2), the motor stator 5 and the motor casing 8 below the shaft center O The refrigerant gas does not flow through the gap between the two. However, in the drive motor 7, the stator windings provided on the stator core of the motor stator 5 generate heat, so that the refrigerant gas flows through the air gap 21, thereby causing the coil ends 5 a and 5 b of the drive motor 7. The part except for can be cooled uniformly.

  By the way, the oil after lubrication of the bearings 11a, 11b, and 12 supporting the screw rotor 10 (male rotor 10A and female rotor 10B) is returned to the gas suction passage R upstream of the suction port 16b through a flow path (not shown). Therefore, in the conventional screw compressor, in order to reduce the temperature at the upper end of the coil end, the refrigerant gas is actively supplied to the gas passage above the shaft center without forming the gas passage below the shaft center of the drive motor. If it flows, oil will accumulate in the lower part of the inner wall of the main casing of the coil end of the drive motor, the lower part of the coil end will be immersed in the accumulated oil, the amount of heat exchange between the refrigerant gas and the coil end will decrease, and the temperature of the coil end will decrease. There is a problem of rising.

  Therefore, in the present embodiment, as shown in FIG. 6, the gas suction passage R is formed with a substantially semi-conical truncated outer peripheral wall surface 23, that is, the flow passage cross-sectional area of the opening edge portion 9 f of the main casing 9 is Since the flow passage cross-sectional area is gradually reduced toward the suction port 16b, the refrigerant gas colliding with the outer peripheral inner wall surface 23 flows through the outer peripheral inner wall surface 23 toward the suction port 16b. As the refrigerant gas flows, the bearing-lubricated drained oil accumulated in the lower portion 5b1 of the coil end 5b rises on the inclined surface 23a of the outer peripheral inner wall surface 23 and is sucked into the screw rotor 10 from the suction port 16b. It is possible to prevent oil from collecting in the lower portion 5b1 of 5b. In this manner, the oil after bearing lubrication accumulated in the lower portion 5b1 of the coil end 5b can be easily introduced into the suction port 16b. In the present embodiment, the gas suction passage R is formed in a substantially semi-conical shape, that is, the outer peripheral inner wall surface 23 (gas suction passage R) is formed to be narrowed toward the suction port 16b. The drain oil can be easily introduced toward the suction port 16b.

  Then, together with the drained oil after bearing lubrication, the refrigerant gas is sucked into the compressor chamber formed by the meshing tooth surface of the screw rotor 10 and the cylindrical bore 16a from the suction port 16b. As the male rotor 10A directly connected to the drive motor 7 is rotated, the refrigerant gas is introduced into the compressor chamber, and is gradually compressed as the compressor chamber is reduced to become a high-temperature and high-pressure gas. It discharges to the discharge port 24 (refer FIG. 1) provided in the casing 9. FIG.

  As shown in FIG. 1, the refrigerant gas (including oil) is sent from the discharge port 24 to the oil separation space 14a of the oil separator 14 to separate the oil. In the oil separator 14, the refrigerant gas and the oil are separated by a centrifugal separation method. The separated oil is accumulated in an oil sump space 14b provided on the bottom side of the oil separator 14 so that only the refrigerant gas is discharged from a discharge port (not shown) provided in the upper portion of the oil separator 14. It is configured.

  The oil that has lubricated and cooled the bearings 11a, 11b, and 12 passes through oil passages (not shown) that communicate with the bearings 11a, 11b, and 12 from an oil sump space 14b formed in the lower portion of the main casing 9. Oil is supplied by differential pressure.

  As described above, in the screw compressor 100 of the present embodiment, the gas suction passage R to the suction port 16b is moved to the coil end 5b below the axial center O of the coil end 5b protruding in the axial direction of the drive motor 7. And the gas passage 20 (see FIG. 2) on the outer periphery of the drive motor 7 is formed above the axial center O, immediately after the coil end 5b on the downstream side of the drive motor 7, and The gas collision member 18 is provided in the upper part of the gas suction passage R. As a result, the refrigerant gas collides with the gas collision member 18 provided immediately after the coil end 5b, so that the refrigerant gas can flow from the upper part to the lower part of the coil end 5b, and from the upper part of the coil end 5b. It becomes possible to uniformly cool the whole over the lower part.

  Thus, in the hermetic screw compressor 100 that cools the drive motor 7 with the refrigerant gas (suction gas), the motor coil (the entire coil of the drive motor 7) can be uniformly cooled with only the refrigerant gas. Therefore, it is possible to improve the reliability of the drive motor 7 and to expand the operating range (temperature zone) of the screw compressor 100.

  In the present embodiment, the gas suction passage R is configured to have the outer peripheral inner wall surface 23 having a substantially semi-conical shape along the coil end 5b, so that the oil after bearing lubrication flows into the outer periphery together with the flow of the refrigerant gas. Since the inclined surface 23a (see FIG. 6) of the wall surface 23 can move toward the suction port 16b, oil can be prevented from collecting in the lower part 5b1 of the coil end 5b, and the temperature of the lower part 5b1 of the coil end 5b rises locally. Can be prevented.

  By the way, in the screw compressors for air conditioners and refrigerators, the amount of suction gas (refrigerant gas) circulates more in the air conditioner than in the refrigerator, so that the cooling efficiency of the drive motor is the one for the air conditioner. Can be set high. On the other hand, if the one for an air conditioner is applied to the one for a refrigerator, the amount of the intake gas (refrigerant gas) circulated in the refrigerator is smaller than that for the air conditioner. It was necessary to increase the cooling flow rate by adjusting the cross-sectional area of the gas passage to be small. In addition, in a screw compressor, a load is applied to the drive motor in severe operation, so a protection device is installed, and the operation is stopped by the protection device when there is a possibility that the load will be excessive. It has been broken. However, since the motor coil of the drive motor can be uniformly cooled as in the above-described embodiment, the operating range (operating temperature range) can be expanded, so that the screw compressor for the air conditioner is used for the refrigerator. In other words, it is possible to eliminate the need for adjustment according to the application, and it is possible to improve the reliability of the drive motor.

  The present invention is not limited to the above-described embodiment. For example, as shown in FIG. 7, when the main casing 9 is cast, the gas collision member 18A may be integrally formed. Good. In addition, about the structure similar to above-described embodiment, the same code | symbol is attached | subjected and the overlapping description is abbreviate | omitted.

  As shown in FIG. 7, in the screw compressor 100A, a gas collision member 18A is formed so as to protrude from the outer peripheral surface of the cylindrical portion 9a. The gas collision member 18A is configured to have the same shape as the gas collision member 18 shown in FIG.

  Thus, by forming the gas collision member 18A integrally with the main casing 9, the work of fastening the gas collision member 18A becomes unnecessary, and the assembly work of the screw compressor 100A can be simplified.

  In the gas collision member 18A shown in FIG. 7, the case where the gas collision member 18A is formed so as to protrude from the cylindrical portion 9a has been described as an example. However, the present invention is not limited to this, and includes the upper inner wall 9e of the main casing 9. You may form so that it may protrude toward the cylindrical part 9a from a wall surface.

DESCRIPTION OF SYMBOLS 1 Motor part 2 Compressor part 3 Capacity | capacitance control mechanism part 4 Inlet 5 Motor stator 5b Coil end 6 Motor rotor 7 Drive motor (motor)
8 Motor casing (casing)
9 Main casing (casing)
9a Cylindrical portion 10 Screw rotor 10A Male rotor 10B Female rotor 11a, 11b Roller bearing 12 Ball bearing 13 Discharge casing (casing)
14 Oil separator 14a Oil separation space 14b Oil reservoir space 16a Cylindrical bore 16b Suction port 18, 18A Gas collision member 20 Gas passage 21 Air gap 23 Outer peripheral inner wall surface 23a Inclined surface 100, 100A Screw compressors G1, G2 Axis O Axis Center R Gas suction passage

Claims (4)

A pair of male and female screw rotors, each axis being parallel and meshing with each other;
A motor for driving the screw rotor;
A hermetically sealed casing that houses the screw rotor and the motor and disposes the motor on the upstream side of the screw rotor with respect to the flow of gas,
The casing forms a gas suction passage to the screw rotor so as to open along the coil end below the axial center of the coil end protruding in the axial direction of the motor.
Forming a gas passage on the outer periphery of the motor stator of the motor only above the axis center;
Immediately after the coil end on the downstream side of the front SL motor, and, on top of the gas suction path causes flow through toward the bottom from the top of the gas passing through the gas passage along the outer peripheral surface of the coil end A screw compressor comprising a gas collision member. The gas suction passage, have a outside inner wall surface formed substantially semi-truncated conical shape along said coil end,
The screw compressor according to claim 1, wherein the outer peripheral inner wall surface has an inclined surface that rises linearly from a position facing the lower portion of the coil end . Before Listen pacing comprises a cylindrical portion which the shaft is inserted extending from said screw rotors,
The screw compressor according to claim 1 or 2, wherein a tip of the cylindrical portion is inserted into a space inside the coil end. The screw compressor according to any one of claims 1 to 3, wherein the gas collision member includes a wall surface of the casing.

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