JP6789201B2 - Liquid-cooled screw compressor - Google Patents

Description

The present invention relates to a liquid-cooled screw compressor.

In an oil-cooled compressor, which is a type of liquid-cooled screw compressor, the heat exchange between the gas during compression and the oil is promoted by devising the arrangement of the injection nozzle (fuel filler port). For example, it is disclosed in Patent Document 1. In the oil-cooled screw compressor of Patent Document 1, the injection direction from the injection nozzle into the compression chamber (rotor chamber) is directed in the direction opposite to the rotation direction of the screw rotor. This ensures a long time for the oil to fly in the gas in the compression chamber and promotes heat exchange between the oil and the gas.

Japanese Unexamined Patent Publication No. 9-151870

Since the liquid-cooled screw compressor rotates the screw rotor at high speed to compress the gas, the time it takes for the liquid to come into contact with the air before it comes into contact with the rotor casing and screw rotor even if the injection direction is changed as described above. It is expected to increase only slightly. Therefore, the heat exchange performance can be expected to be slightly improved, and there is room for improvement in order to further improve the heat exchange performance. Furthermore, no particular study has been made on the improvement of the sealing performance by the liquid between the male rotor, the female rotor and the rotor casing.

An object of the present invention is to improve heat exchange performance and sealing performance in a liquid-cooled screw compressor.

The present invention comprises a male rotor, a female rotor that meshes with the male rotor and has a rotation axis parallel to the rotation axis of the male rotor, a male rotor chamber accommodating the male rotor, and a female rotor accommodating the female rotor. The rotor casing that defines the chamber and the rotor casing are provided so as to supply liquid to at least one side of the male rotor chamber and the female rotor chamber, and are arranged so as to be out of phase with respect to the rotation axis on the one side. Provided is a liquid-cooled screw compressor provided with at least two liquid supply ports.

According to this configuration, since the rotor casing is provided with at least two liquid supply ports that are out of phase around the rotation axis, uneven distribution of liquid can be prevented. By preventing uneven distribution of the liquid, heat exchange between the liquid and the compressed gas is promoted, the heat exchange performance can be improved, and the sealing performance by the liquid between the male rotor, the female rotor and the rotor casing can also be improved. Therefore, since the compression efficiency is improved, the energy saving performance can be improved.

The at least two liquid supply ports may be provided at different positions in the direction of the rotation axis on one side of the liquid supply port.

According to this configuration, the liquid can be widely supplied not only around the rotation axis but also in the direction in which the rotation axis extends, so that uneven distribution of the liquid can be further prevented. By preventing uneven distribution of the liquid, as described above, the heat exchange performance and the sealing performance can be improved, so that the compression efficiency can be improved and the energy saving performance can be improved.

The at least two liquid supply ports may be arranged in a straight line, and a linear liquid supply pipe connecting the at least two liquid supply ports may be further provided.

According to this configuration, since the liquid supply pipe is linear, it is possible to prevent the shape of the liquid supply pipe from becoming complicated and reduce the man-hours for processing the liquid supply pipe. It is not necessary that all of the liquid supply ports are provided on a straight line, and in addition to the plurality of liquid supply ports arranged on the straight line, there may be a liquid supply port arranged outside the straight line.

In the direction of the rotation axis on one side, the distance between the farthest points of the adjacent liquid supply ports may be smaller than the tooth groove width on the one side.

According to this configuration, at least two liquid supply ports can be arranged in one tooth groove. Therefore, it is possible to suppress the lack of liquid in the tooth groove. Therefore, the cooling performance and the sealing performance with a sufficient amount of liquid can be improved, and the compression efficiency can be improved.

In the direction of the rotation axis on one side, the distance between the latest points of the adjacent liquid supply port is larger than the tooth groove width on the one side, or the distance between the farthest points of the adjacent liquid supply port is the said. It may be smaller than the width of the tooth groove on one side.

According to this configuration, noise can be reduced. Temporarily, the distance between the most recent points of the adjacent liquid supply port is smaller than the width of the tooth groove on the side of the male rotor or female rotor where the liquid supply port is provided, and the distance between the farthest points of the adjacent liquid supply port is If it is larger than the width of the tooth groove on the side of the male rotor or the female rotor where the liquid supply port is provided, the tooth tips are located at the two liquid supply ports at the same time. Since the pressure at the liquid supply port suddenly increases due to centrifugal force when the tooth tip passes through, the pressure in the liquid supply pipe rises sharply when a sudden pressure rise occurs at the same time at two adjacent liquid supply ports. A sudden rise in pressure in the liquid supply pipe causes pulsation, and this pulsation causes noise. Therefore, noise can be reduced by providing the liquid supply port while avoiding the above case.

A first virtual line segment connecting the rotation center point of the male rotor or the female rotor on one side and the discharge side cusp point connecting the male rotor chamber and the female rotor chamber in a cross section perpendicular to the rotation axis. A second virtual line segment is defined by rotating the first virtual line segment around the rotation center point on one side by a first predetermined angle in a direction away from the discharge side cusp point. The liquid port may be provided in a range excluding the range from the first virtual line segment to the second virtual line segment.

According to this configuration, it is possible to prevent the liquid from concentrating at the meshing position (generally coincident with the cusp point) between the male rotor and the female rotor. Generally, in a liquid-cooled screw compressor, the rotation of the male rotor and the female rotor tends to concentrate the liquid at the meshing position between the male rotor and the female rotor. If the liquid supply port is provided in the range from the first virtual line segment to the second virtual line segment, the liquid will be supplied near the meshing position between the male rotor and the female rotor, so that the liquid will be concentrated at the meshing position. As a result, the stirring loss of the liquid becomes excessive and the compression efficiency may deteriorate. However, in the above configuration, since the liquid supply port is provided at a position slightly distant from the meshing position (the range excluding the range from the first virtual line segment to the second virtual line segment), concentration of the liquid can be prevented and the compression efficiency can be prevented. Can be prevented from deteriorating. Here, the first predetermined angle is an angle that can prevent the liquid from concentrating on the meshing position, and is determined according to the shapes of the male rotor and the female rotor, the shape of the rotor casing, the type of the liquid, and the like.

In the cross section perpendicular to the rotation axis, a first center line passing through the rotation center point of the male rotor and the rotation center point of the female rotor is defined, orthogonal to the first center line, and the rotation center on one side thereof. A second center line passing through the point is defined, and a third virtual line segment rotated by a second predetermined angle from the second center line in a direction away from the discharge side cusp point is defined around the rotation center point on one side. However, the first liquid supply port, which is one of the at least two liquid supply ports, may be provided in the range from the second virtual line segment to the third virtual line segment.

According to this configuration, the sealing property at the meshing position between the male rotor and the female rotor can be ensured. If the liquid supply port is arranged at a position significantly far from the meshing position, the liquid may not be sufficiently supplied to the meshing position between the male rotor and the female rotor. In that case, gas leakage may occur at the meshing position between the male rotor and the female rotor, and the compression efficiency may deteriorate. However, in the above configuration, since the liquid supply port is provided in the range from the second virtual line segment to the third virtual line segment, the liquid can be sufficiently supplied to the meshing position. Therefore, the sealing property at the meshing position can be ensured, and deterioration of the compression efficiency can be prevented. Here, the second predetermined angle is an angle that can prevent a liquid shortage at the meshing position, and is determined according to the shapes of the male rotor and the female rotor, the shape of the rotor casing, the type of liquid, and the like.

In the cross section perpendicular to the rotation axis, the second liquid supply port, which is one of the at least two liquid supply ports, is located around the rotation center point on one side from the first liquid supply port. It may be provided in the range up to the suction side cusp point connecting the male rotor chamber and the female rotor chamber.

According to this configuration, uneven distribution of the liquid can be prevented. Considering the distribution of the supplied liquid, as described above, the liquid tends to concentrate at the meshing position between the male rotor and the female rotor due to the rotation of the male rotor and the female rotor. Therefore, the amount of liquid at a position away from the meshing position is small, and at a position away from the meshing position, the sealing performance tends to deteriorate due to the liquid film breaking. Therefore, by providing the second liquid supply port in the above range, the liquid can be supplied to a position where the amount of liquid is small, and uneven distribution of the liquid can be prevented.

The rotor casing has suction ports at positions corresponding to the ends of the male rotor and the female rotor in the direction of the rotation axis, and the liquid supply port closest to the suction port among the at least two liquid supply ports. The position of may be separated from the suction port by the width of the tooth groove on the side of the male rotor or the female rotor where the liquid supply port is provided.

According to this configuration, even if the male rotor and the female rotor rotate, the liquid supply port closest to the suction port (the lowest pressure side) and the suction port are not fluidly connected. Therefore, it is possible to prevent the liquid from leaking to the suction port, causing suction heating, and reducing the volumetric efficiency.

The rotor casing has a discharge port at a position corresponding to the ends of the male rotor and the female rotor in the direction of the rotation axis, and the liquid supply port closest to the discharge port among the at least two liquid supply ports. The position of may be separated from the discharge port by the width of the tooth groove on the side of the male rotor or the female rotor where the liquid supply port is provided.

According to this configuration, even if the male rotor and the female rotor rotate, the liquid supply port closest to the discharge port (the highest pressure side) and the discharge port are not fluidly connected. Therefore, it is possible to prevent the liquid from flowing back from the discharge port into the liquid supply port and reduce the volumetric efficiency, and it is possible to prevent power loss due to recompression.

According to the present invention, in the liquid-cooled screw compressor, since the liquid can be supplied by shifting the phase around the rotation axis, uneven distribution of the liquid can be prevented, and heat exchange performance and sealing performance can be improved.

Partial schematic block diagram of the oil-cooled screw compressor according to the first embodiment of the present invention. Schematic cross-sectional view of the rotor casing along lines II-II of FIG. Schematic sectional view showing the position of the fuel filler port in the rotor casing. Schematic sectional view showing the position of the fuel filler port in the rotor casing. Cross-sectional view showing the arrangement of the rotor casing of the oil-cooled screw compressor of the first modification. Cross-sectional view showing the arrangement of the rotor casing of the oil-cooled screw compressor of the second modification. Schematic sectional view showing the position of the fuel filler port in the rotor casing of the oil-cooled screw compressor according to the second embodiment. Schematic sectional view showing the position of the fuel filler port in the rotor casing of the oil-cooled screw compressor according to the third embodiment. Schematic sectional view showing the position of the fuel filler port in the rotor casing of the oil-cooled screw compressor according to the fourth embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. As the embodiment of the present invention, an oil-cooled compressor using oil as the liquid supplied into the rotor casing is shown. Therefore, hereinafter, "oil" may be read as "liquid".

(First Embodiment)
FIG. 1 is a partial schematic configuration diagram of an oil-cooled screw compressor 1 according to a first embodiment of the present invention. Hereinafter, the oil-cooled screw compressor 1 is also simply referred to as a compressor 1. FIG. 1 shows a part of the compressor 1 particularly related to the compression mechanism. The compressor 1 sucks air from the outside, compresses it internally, and discharges it. The air discharged from the compressor 1 is supplied to the supply destination through a pipe (not shown).

The compressor 1 includes a rotor casing 10 and bearing casings 20 and 21. In the present embodiment, the rotor casing 10 and the bearing casings 20 and 21 are integrated. The rotor casing 10 is arranged between the two bearing casings 20, 21. The rotor casing 10 internally defines a rotor chamber 30, and the two bearing casings 20 and 21 internally define bearing chambers 33 and 34, respectively. The rotor chamber 30 and the bearing chamber 33 are partitioned via the partition wall 11, and the rotor chamber 30 and the bearing chamber 34 are partitioned via the partition wall 12. The partition walls 11 and 12 are both part of the rotor casing 10.

In the rotor casing 10, a male rotor 50 and a female rotor 60 that meshes with the male rotor 50 and has more teeth than the male rotor 50 are arranged. That is, the screw rotor 40 is composed of the male rotor 50 and the female rotor 60. Although details are not shown, in this embodiment, for example, the male rotor 50 has a four-toothed shape and the female rotor 60 has a six-toothed shape.

FIG. 2 is a schematic cross-sectional view of the rotor casing 10 along the line II-II of FIG. The rotor casing 10 defines a male rotor chamber 31 accommodating a male rotor 50 and a female rotor chamber 32 accommodating a female rotor 60. The rotor chamber 30 is a space in which the male rotor chamber 31 and the female rotor chamber 32 are combined. The rotor casing 10 has a shape in which two cylinders are connected to each other on the side surface. In other words, the male rotor chamber 31 and the female rotor chamber 32 are both cylindrical spaces and communicate with each other.

FIG. 2 is also a cross-sectional view of the female rotor 60 (see FIG. 1) as viewed from the direction of rotation axis. In the present embodiment, the rotation axis of the female rotor 60 and the rotation axis of the male rotor 50 extend horizontally in parallel with each other, and the male rotor chamber 31 and the female rotor chamber 32 extend in the same direction. In the cross-sectional view of FIG. 2, the male rotor chamber 31 and the female rotor chamber 32 are connected by a suction side cusp point 14a and a discharge side cusp point 14b. The lowest point P3 of the male rotor chamber 31 is located below the discharge side cusp point 14b that connects the male rotor chamber 31 and the female rotor chamber 32.

As shown in FIG. 1, a shaft member 51, which is a rotation axis of the male rotor 50, extends from one end of the male rotor 50. The shaft member 51 extends through the partition wall 11 from the male rotor chamber 31 to the bearing chamber 33, and is rotatably supported by the bearing 54 in the bearing chamber 33. Further, a shaft member 61, which is a rotation axis of the female rotor 60, extends from one end of the female rotor 60. The shaft member 61 penetrates the partition wall 11 and extends from the female rotor chamber 32 to the bearing chamber 33, and is rotatably supported by the bearing 63 in the bearing chamber 33.

A shaft member 52, which is a rotation shaft of the male rotor 50, extends from the other end of the male rotor 50. The shaft member 52 penetrates the partition wall 12 and extends from the male rotor chamber 31 to the bearing chamber 34, and is rotatably supported by the bearing 54 in the bearing chamber 34. Further, a shaft member 62, which is a rotation shaft of the female rotor 60, extends from the other end of the female rotor 60. The shaft member 62 penetrates the partition wall 12 and extends from the female rotor chamber 32 to the bearing chamber 34, and is rotatably supported by the bearing 64 in the bearing chamber 34. In particular, the shaft member 52 of the male rotor 50 extends to a motor (not shown) and is mechanically connected to this motor. Therefore, the male rotor 50 is rotationally driven by this motor, the rotational power is transmitted from the male rotor 50 to the female rotor 60, and the male rotor 50 and the female rotor 60 mesh with each other to rotate and compress the air. In FIG. 1, the right side is the suction side and the left side is the discharge side. Therefore, when the male rotor 50 and the female rotor 60 rotate, air is sucked from the bearing chamber 34 side and air is discharged to the bearing chamber 33 side in the rotor chamber 30.

As shown in FIG. 2, the rotor casing 10 is provided with a fuel filler port (first fuel filler port) 13a and a fuel filler port (second fuel filler port) 13b only on the female rotor chamber 32 side. The refueling port 13a and the refueling port 13b are arranged so as to be out of phase around the rotation center point P1 of the female rotor 60. Hereinafter, the refueling ports 13a and 13b are also simply referred to as refueling ports 13. Three virtual line segments S1 to S3 are defined to define the detailed position of the fuel filler port 13. It is defined as the first virtual line segment S1 connecting the rotation center point P1 of the female rotor 60 and the discharge side cusp point 14b. A second virtual line segment S2 is defined in which the first virtual line segment S1 is rotated by a first predetermined angle θ1 around the rotation center point P1 of the female rotor 60 in a direction away from the male rotor 50. Here, the first predetermined angle θ1 is an angle that can prevent oil from concentrating on the meshing position (which roughly coincides with the discharge side cusp point 14b), and is the shape of the male rotor 50 and the female rotor 60, and the rotor casing 10. It is determined according to the shape of the oil and the type of oil. Then, the first center line L1 including the rotation center point P2 of the male rotor 50 and the rotation center point P2 of the female rotor 60 is defined. The first center line L1 is a horizontal line. Further, a second center line L2 that is orthogonal to the first center line L1 and passes through the rotation center point P1 of the female rotor 60 is defined. Then, a third virtual line segment S3 is defined, which is rotated by a second predetermined angle θ2 from the second center line L2 in a direction away from the discharge side cusp point 14b around the rotation center point P1 of the female rotor 60. Here, the second predetermined angle θ2 is an angle that can prevent oil shortage at the meshing position, depending on the shapes of the male rotor 50 and the female rotor 60, the shape of the rotor casing 10, the type of oil, and the like. It is decided.

The fuel filler port 13a is provided in a range excluding the range from the first virtual line segment S1 to the second virtual line segment S2, and specifically, is provided in the range from the second virtual line segment S2 to the third virtual line segment S3. Is preferable. More specifically, it is preferable that even a part of the fuel filler port 13a is provided in the range from the second virtual line segment S2 to the third virtual line segment S3. Here, the first predetermined angle θ1 is preferably, for example, about 30 degrees or more. Further, the second predetermined angle θ2 is, for example, about 1/4 or less of the angle of one tooth of the female rotor 60, and since the female rotor 60 having a 6-tooth shape is adopted in this embodiment, it is 15 degrees. It is preferably less than or equal to the degree. In the present embodiment, the fuel filler port 13a is provided in the range from the second virtual line segment S2 to the third virtual line segment S3, and specifically, is provided on the second center line L2.

The fuel filler port 13b is preferably provided around the rotation center point P1 in a range from the fuel filler port 13a to the suction side cusp point 14a (see the thick line portion in the figure). In the present embodiment, the fuel filler port 13b is provided at a position of about 30 degrees from the fuel filler port 13a around the rotation center point P1 and from the fuel filler port 13a toward the suction side cusp point 14a.

FIG. 3 is a schematic cross-sectional view showing the positions of the fuel filler ports 13a and 13b in the rotor casing 10. In the present embodiment, a plurality of (three in FIG. 3) refueling ports 13a are arranged in a straight line in a manner connected by a linear refueling pipe 15a, and a plurality of (two in FIG. 3) refueling ports are arranged. The 13b is also arranged in a straight line in a manner connected by another linear refueling pipe 15b. That is, in this embodiment, two refueling pipes 15a and 15b are provided. The two refueling pipes 15a and 15b extend parallel to the rotation axis of the female rotor 60. The three fuel filler ports 13a are arranged at equal intervals c1, and the two fuel filler ports 13b are arranged at intervals c2. The distance d1 between the farthest points between the adjacent refueling ports 13a (the distance d1 of the farthest part between the adjacent refueling ports 13a) and the distance d2 between the farthest points between the refueling ports 13b (the farthest between the adjacent refueling ports 13b). The distance d2) of the portions is smaller than the tooth groove width D1 of the female rotor 60 (d1, d2 <D1). That is, at least two fuel filler ports 13 are arranged in one tooth groove. In the present embodiment, the radius r1 of the fuel filler port 13a and the radius r2 of the fuel filler port 13b are the same, the interval c1 and the interval c2 are also the same, and the distance d1 between the farthest points and the distance d2 between the farthest points are also the same. Is.

Further, due to this arrangement, as will be described later, the tooth tips of the female rotor 60 are not simultaneously positioned at the two adjacent oil filler ports 13a or the two oil filler ports 13b, so that the pressure in the oil supply pipe 15 is as described later. Can be prevented from rising sharply. Further, in order to prevent this sudden rise in pressure, the distance between the latest points d3 between the adjacent refueling ports 13a (the distance d3 of the closest portion between the adjacent refueling ports 13a) and the distance between the latest points between the refueling ports 13b. The d4 (distance d4 of the closest portion between the adjacent refueling ports 13b) may be made larger than the tooth groove width D1 of the female rotor 60 (d3, d4> D1).

As shown in FIGS. 3 and 4, the rotor casing 10 has a suction port 10a on one end side (upper side in FIG. 3 and right side in FIG. 4) of the screw rotor 40 in the rotation axis direction. The suction port 10a is provided in the upper part of the rotor casing 10 and extends around the male rotor 50 and the female rotor 60. Further, in the rotation axis direction, the position of the fuel filler port 13a closest to the suction port 10a among the plurality of fuel filler ports 13a and 13b is separated from the suction port 10a by the tooth groove width D1 or more of the female rotor 60. That is, the distance Δ1 from the fuel filler port 13a closest to the suction port 10a among the plurality of fuel filler ports 13a and 13b to the suction port 10a is equal to or larger than the tooth groove width D1 of the female rotor 60 (Δ1 ≧ D1).

Further, the rotor casing 10 has a discharge port 10b on the other end side (upper side in FIG. 3 and left side in FIG. 4) in the rotation axis direction. The discharge port 10b is provided in the lower part of the rotor casing 10. In the direction of the rotation axis, the position of the refueling port 13a closest to the discharge port 10b among the plurality of refueling ports 13a and 13b is separated from the discharge port 10b by the tooth groove width D1 or more of the female rotor 60. That is, the distance Δ2 from the fuel filler port 13a closest to the discharge port 10b among the plurality of fuel filler ports 13a and 13b to the discharge port 10b is equal to or larger than the tooth groove width D1 of the female rotor 60 (Δ2 ≧ D1).

Hereinafter, the operation and effect of the compressor 1 of the present embodiment will be described.

According to the present embodiment, as shown in FIG. 2, since the rotor casing 10 is provided with a plurality of oil filler ports 13a and 13b out of phase around the rotation axis of the female rotor 60, uneven distribution of oil is prevented. it can. By preventing uneven distribution of oil, heat exchange between oil and compressed gas can be promoted, heat exchange performance can be improved, and sealing performance by oil between the male rotor 50, the female rotor 60, and the rotor casing 10 can also be improved. .. Therefore, since the compression efficiency is improved, the energy saving performance can be improved.

Further, according to the present embodiment, as shown in FIG. 3, a plurality of fuel filler ports 13 are provided at different positions in the direction in which the rotation axis of the female rotor 60 extends. Therefore, since oil can be widely supplied not only around the rotation axis but also in the direction in which the rotation axis extends, uneven distribution of oil can be further prevented. By preventing the uneven distribution of oil, as described above, the heat exchange performance and the sealing performance can be improved, so that the compression efficiency can be improved and the energy saving performance can be improved.

Further, according to the present embodiment, since the refueling pipes 15a and 15b are linear, it is possible to prevent the shapes of the refueling pipes 15a and 15b from becoming complicated and reduce the man-hours for processing the refueling pipes 15a and 15b.

Further, according to the present embodiment, since the distances d1 and d2 between the farthest points of the refueling ports 13a and 13b are defined to be less than the tooth groove width D1, at least two refueling ports 13 are arranged in one tooth groove. it can. Therefore, the oil shortage in the tooth groove can be suppressed. Therefore, the cooling performance and the sealing performance with a sufficient amount of oil can be improved, and the compression efficiency can be improved.

Further, according to the present embodiment, noise can be reduced. With reference to FIG. 3, tentatively, the distance between the latest points d3 between the adjacent refueling ports 13a or the distance d4 between the latest points between the adjacent refueling ports 13b is smaller than the tooth groove width D1 of the female rotor 60 and is adjacent to each other. The distance d1 between the farthest points of the refueling ports 13a or the distance d2 between the farthest points of the adjacent refueling ports 13b (the distance d2 of the farthest part between the adjacent refueling ports 13b) is the tooth groove width D1 of the female rotor 60. If it is larger than (d1, d2> D1> d3, d4), the tooth tips will be located at two adjacent fuel filler ports 13a, 13a or two adjacent fuel filler ports 13b, 13b at the same time. Since the pressure at the fuel filler port 13 suddenly increases due to centrifugal force when the tooth tip passes, if a sudden pressure rise occurs at the two adjacent fuel filler ports 13a, 13a or the two adjacent fuel filler ports 13b, 13b at the same time. The pressure in the refueling pipes 15a and 15b rises sharply. A sudden rise in pressure in the refueling pipes 15a and 15b causes pulsation, and this pulsation causes noise. Therefore, noise can be reduced by providing the fuel filler port 13 in avoiding the above case.

Further, according to the present embodiment, it is possible to prevent the oil from concentrating at the meshing position between the male rotor 50 and the female rotor 60. Generally, in the oil-cooled screw compressor 1, the rotation of the male rotor 50 and the female rotor 60 tends to concentrate the oil at the meshing position between the male rotor 50 and the female rotor 60. If the oil filler port 13a is provided in the range from the first virtual line segment S1 to the second virtual line segment S2, oil will be supplied near the meshing position between the male rotor 50 and the female rotor 60, so that the oil is in the meshing position. By concentrating on the oil, the stirring loss of the oil becomes excessive and the compression efficiency may deteriorate. However, in the configuration of the present embodiment, since the fuel filler port 13a is provided at a position slightly distant from the meshing position (a range excluding the range from the first virtual line segment S1 to the second virtual line segment S2), the oil is concentrated. Can be prevented, and deterioration of compression efficiency can be prevented.

Further, according to the present embodiment, the sealing property at the meshing position between the male rotor 50 and the female rotor 60 can be ensured. If the oil filler port is arranged at a position significantly far from the meshing position, oil may not be sufficiently supplied to the meshing position between the male rotor 50 and the female rotor 60. In that case, gas leakage may occur at the meshing position between the male rotor 50 and the female rotor 60, and the compression efficiency may deteriorate. However, in the configuration of the present embodiment, since the fuel filler port 13a is provided in the range from the second virtual line segment S2 to the third virtual line segment S3, sufficient oil can be supplied to the meshing position. Therefore, the sealing property at the meshing position can be ensured, and deterioration of the compression efficiency can be prevented.

Further, according to the present embodiment, uneven distribution of oil can be prevented. Considering the distribution of the refueled oil, as described above, the rotation of the male rotor 50 and the female rotor 60 tends to concentrate the oil at the meshing position between the male rotor 50 and the female rotor 60. Therefore, the amount of oil at a position away from the meshing position is small, and at a position away from the meshing position, the sealing performance tends to deteriorate due to the oil film running out. Therefore, by providing the oil filler port 13b in the range from the oil filler port 13a to the suction side cusp point 14a, it is possible to supply oil at a position where the amount of oil is small, and it is possible to prevent uneven distribution of oil.

Further, according to the present embodiment, the distance Δ1 from the fuel filler port 13a closest to the suction port 10a among the plurality of fuel filler ports 13a and 13b to the suction port 10a is equal to or larger than the tooth groove width D1 of the female rotor 60. Therefore, even if the male rotor 50 and the female rotor 60 rotate, the fuel filler port 13a closest to the suction port 10a (on the lowest pressure side) and the suction port 10a are not fluidly connected. Therefore, it is possible to prevent the oil from leaking to the suction port 10a, causing suction heating, and reducing the volumetric efficiency.

Further, according to the present embodiment, the distance Δ2 from the fuel filler port 13a closest to the discharge port 10b among the plurality of fuel filler ports 13a and 13b to the discharge port 10b is equal to or larger than the tooth groove width D1 of the female rotor 60. Therefore, even if the male rotor 50 and the female rotor 60 rotate, the fuel filler port 13a and the discharge port 10b closest to the discharge port 10b (on the highest pressure side) are not fluidly connected. Therefore, it is possible to prevent the oil from flowing back from the discharge port 10b into the oil supply port 13 and reduce the volumetric efficiency, and it is possible to prevent power loss due to recompression.

(First modification)
FIG. 5 is a cross-sectional view of the rotor casing 10 of the compressor 1 of the first modification, and is a view corresponding to FIG. In the compressor 1 of this modification, the rotor casing 10 is arranged in a state where the first center line L1 is inclined from the horizontal line HL.

In this modification, the rotation axis CL1 of the female rotor 60 and the rotation axis CL2 of the male rotor 50 are not arranged in the horizontal plane, and the rotation axis CL1 of the female rotor 60 is lower than the rotation axis CL2 of the male rotor 50. It is located in. Specifically, the first center line L1 is, for example, about 30 degrees from the horizontal line HL. Therefore, the female rotor chamber 32 is arranged below the male rotor chamber 31. As described above, even when the first center line L1 is not horizontal, the relative positions of those constituting the present invention do not change, and whether or not the first center line L1 is horizontal is determined by the present invention. It has no effect on the effect.

(Second modification)
FIG. 6 is a cross-sectional view of the rotor casing 10 of the compressor 1 of the second modification, and is a view corresponding to FIG. In the compressor 1 of the present embodiment, the rotor casing 10 is arranged in a state where the first center line L1 is vertical.

In this modification, the rotating shaft CL1 of the female rotor 60 and the rotating shaft CL2 of the male rotor 50 are not arranged in the horizontal plane, and the rotating shaft CL2 of the male rotor 50 is directly below the rotating shaft CL1 of the female rotor 60. Have been placed. Therefore, the entire male rotor chamber 31 is arranged below the entire female rotor chamber 32.

(Second Embodiment)
FIG. 7 is a cross-sectional view of the rotor casing 10 of the compressor 1 of the second embodiment, and is a view corresponding to FIG. 3 of the first embodiment. The compressor 1 of the present embodiment is the same as the configuration of the compressor 1 of the first embodiment except for the configuration related to the fuel filler port 13. Therefore, the same parts as those shown in the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

In the present embodiment, the number of refueling ports 13a provided in the refueling pipe 15a is two, and the number of refueling ports 13b provided in the refueling pipe 15b is one. As described above, the number of refueling ports 13 is not particularly limited.

(Third Embodiment)
FIG. 8 is a cross-sectional view of the rotor casing 10 of the compressor 1 of the third embodiment, and is a view corresponding to FIG. 3 of the first embodiment. The compressor 1 of the present embodiment is the same as the configuration of the compressor 1 of the first embodiment except for the configuration related to the fuel filler port 13. Therefore, the same parts as those shown in the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

In the present embodiment, in addition to the two refueling pipes 15a and 15b for connecting the refueling ports 13a and 13b to the female rotor chamber 32 described in the first embodiment, the refueling port 13c to the male rotor chamber 31 is connected. One refueling pipe 15c is provided. Hereinafter, the fuel filler ports 13a, 13b, and 13c are also simply referred to as the fuel filler ports 13.

With reference to FIG. 2, the refueling port 13c to the male rotor chamber 31 is orthogonal to the first center line L1 and defines the third center line L3 passing through the rotation center point P2 of the male rotor 50. The mouth 13c is provided on the third center line L3. The three refueling ports 13c are provided on a straight line and are connected by a linear refueling pipe 15c.

The distance d5 between the farthest points of the adjacent refueling ports 13c (distance d5 of the farthest portion between the adjacent refueling ports 13c) is smaller than the tooth groove width D2 of the male rotor 50 (d5 <D2). Due to this dimensional relationship, when the male rotor 50 rotates and its tooth tip moves, at least two refueling ports 13c are arranged in one tooth groove. Further, by this arrangement, since the tooth tips of the female rotor 60 are not positioned at the same time in the two adjacent fuel filler ports 13c, it is possible to prevent a sudden rise in the pressure in the fuel filler pipe 15c. Further, in order to prevent this sudden rise in pressure, the distance d6 between the latest points between the adjacent refueling ports 13c (the distance d6 of the closest portion between the adjacent refueling ports 13c) is set to the tooth groove width D2 of the male rotor 50. May be greater than (d6> D2).

The distance Δ3 from the fuel filler port 13c closest to the suction port 10a to the suction port 10a among the plurality of fuel filler ports 13c is equal to or larger than the tooth groove width D2 of the male rotor 50. Further, the distance Δ4 from the fuel filler port 13c closest to the discharge port 10b to the discharge port 10b among the plurality of fuel filler ports 13c is equal to or larger than the tooth groove width D2 of the male rotor 50.

In this way, the refueling port 13 may be arranged so as to refuel the male rotor chamber 31. The operation and effect of the compressor 1 of the present embodiment is substantially the same as that of the first embodiment.

(Fourth Embodiment)
FIG. 9 is a cross-sectional view of the rotor casing 10 of the compressor 1 of the fourth embodiment, and is a view corresponding to FIG. 3 of the first embodiment. The compressor 1 of the present embodiment is the same as the configuration of the compressor 1 of the first embodiment except for the configuration related to the fuel filler port 13. Therefore, the same parts as those shown in the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

In the present embodiment, the directions of the two refueling pipes 15a and 15b connecting the refueling ports 13a and 13b to the female rotor chamber 32 described in the first embodiment are inclined from the rotation axis. Further, the refueling pipes 15a and 15b are provided with two refueling ports 13a and 13b, respectively. In this way, the refueling pipes 15a and 15b may be arranged so as to be inclined from the rotation axis.

Although the specific embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications can be made within the scope of the present invention.

In particular, in each of the above embodiments, the arrangement configuration of the fuel filler port 13 provided on the female rotor 60 side can be similarly applied to the male rotor 50 side, and vice versa. That is, the arrangement configuration of the fuel filler port 13 of each of the above embodiments can be adopted for either or both of the male rotor 50 and the female rotor 60 without distinguishing between the male rotor 50 and the female rotor 60.

As described above, as the embodiment of the present invention, an oil-cooled compressor using oil as the liquid supplied into the rotor casing is shown. However, the present invention can be applied to liquid-cooled compressors other than oil-cooled compressors. For example, the present invention can also be applied to a water injection compressor that uses water as the liquid to be supplied into the rotor casing.

1 Compressor (oil-cooled screw compressor)
10 Rotor casing 10a Suction port 10b Discharge port 11, 12 Partition wall 13 Refueling port 13a Refueling port (first refueling port)
13b Refueling port (2nd refueling port)
13c Refueling port 14 cusp point 14a Suction side cusp point 14b Discharge side cusp point 15a, 15b, 15c Refueling pipe 20,21 Bearing casing 30 Rotor room 31 Male rotor room 32 Female rotor room 33,34 Bearing room 40 Screw rotor 50 Male rotor 51,52 Shaft member 53,54 Bearing 60 Female rotor 61,62 Shaft member 63,64 Bearing

Claims (9)

With a male rotor
A female rotor that meshes with the male rotor and has a rotation axis parallel to the rotation axis of the male rotor.
A rotor casing defining a male rotor chamber accommodating the male rotor and a female rotor chamber accommodating the female rotor, and
In the rotor casing, at least two liquid supply ports provided so as to supply liquid to at least one side of the male rotor chamber and the female rotor chamber and arranged in phase with respect to the rotation axis on the one side. equipped with a,
The at least two liquid supply ports include liquid supply ports arranged in a straight line along the rotation axis direction.
A liquid-cooled screw compressor further provided with a linear liquid supply pipe connecting the liquid supply ports arranged on the straight line . The liquid-cooled screw compressor according to claim 1, wherein the at least two liquid supply ports are provided at different positions in the direction of the rotation axis on one side. In the one side direction of the rotating shaft of the, between the farthest point distance of the liquid supply port adjacent to the said one less than the tooth width of the side, according to claim 1 or is according to claim 2 liquid cooling Type screw compressor. In the direction of the rotation axis on one side, the distance between the latest points of the adjacent liquid supply port is larger than the tooth groove width on the one side, or the distance between the farthest points of the adjacent liquid supply port is the said. The liquid-cooled screw compressor according to claim 2 or 3, which is smaller than the tooth groove width on one side. In the cross section perpendicular to the axis of rotation
A first virtual line segment connecting the rotation center point of the male rotor or the female rotor on one side and the discharge side cusp point connecting the male rotor chamber and the female rotor chamber is defined.
A second virtual line segment obtained by rotating the first virtual line segment around the rotation center point on one side by a first predetermined angle in a direction away from the discharge side cusp point is defined.
The liquid-cooled screw compressor according to any one of claims 1 to 4 , wherein the liquid supply port is provided in a range excluding the range from the first virtual line segment to the second virtual line segment. Machine. In the cross section perpendicular to the axis of rotation
A first center line passing through the rotation center point of the male rotor and the rotation center point of the female rotor is defined.
A second center line that is orthogonal to the first center line and passes through the rotation center point on one side is defined.
A third virtual line segment rotated by a second predetermined angle from the second center line in a direction away from the discharge side cusp point is defined around the rotation center point on one side.
The first liquid supply ports wherein a single liquid supply ports of the at least two liquid supply ports are provided in a range of up to the third virtual line segment from the second phantom line segment, according to claim 5 Liquid-cooled screw compressor. In the cross section perpendicular to the axis of rotation
The second liquid supply port, which is one of the at least two liquid supply ports, has a male rotor chamber and a female rotor chamber from the first liquid supply port around the rotation center point on one side. The liquid-cooled screw compressor according to claim 6 , which is provided in the range up to the suction side cusp point to connect with. The rotor casing has a suction port at a position corresponding to the ends of the male rotor and the female rotor in the direction of the rotation axis.
The position of the liquid supply port closest to the suction port among the at least two liquid supply ports is equal to or larger than the tooth groove width of the male rotor or the female rotor on the side where the liquid supply port is provided, from the suction port. The liquid-cooled screw compressor according to any one of claims 1 to 7 , which is separated. The rotor casing has a discharge port at a position corresponding to the ends of the male rotor and the female rotor in the direction of the rotation axis.
The position of the liquid supply port closest to the discharge port among the at least two liquid supply ports is equal to or larger than the tooth groove width of the male rotor or the female rotor on the side where the liquid supply port is provided. The liquid-cooled screw compressor according to any one of claims 1 to 8 , which is separated.

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