JP7023739B2 - Scroll fluid machine - Google Patents

Description

The present invention relates to a scroll fluid machine.

Generally, there is known a scroll fluid machine that engages a fixed scroll member provided with a spiral wall body on an end plate and a swivel scroll member to perform a revolving swivel motion to compress or expand a fluid. Among scroll fluid machines, a scroll compressor is a device that compresses a refrigerant that circulates in a refrigeration cycle, which is applied to, for example, an air conditioner.

Further, as the refrigeration cycle, a two-stage compression refrigeration cycle in which the refrigerant is divided into two stages and compressed may be used in order to improve the capacity of the heat pump and the COP (coefficient of performance). In the two-stage compression refrigeration cycle, an economizer (gas-liquid separator) is provided between the two expansion valves, and a refrigerant having an intermediate pressure is introduced from the economizer in the middle of the compression process. This refrigeration cycle is also called a gas injection cycle or an economizer cycle.

Japanese Unexamined Patent Publication No. 2006-312898

In order to realize the above-mentioned two-stage compression / refrigeration cycle, one of the following three types is required as the structure of the compressor. (1) In a two-stage compressor in which a high-stage compression unit and a low-stage compression unit are housed inside one compressor, an intermediate pressure is applied between the discharge side of the low-stage compression unit and the suction side of the high-stage compression unit. Introduce the refrigerant. (2) Two single-stage compressors having only one compression unit are connected in series, and an intermediate pressure refrigerant is introduced between the discharge side of the low-stage compressor and the suction side of the high-stage compressor. (3) In a single-stage compressor having only one compression unit, an intermediate pressure refrigerant is introduced during the compression process of the compression unit.

In the case of (1) above, since a two-stage compressor that houses the high-stage compression unit and the low-stage compression unit is required, the structure of the compressor itself becomes complicated. In the case of (2) above, since two compressors are required, the system constituting the refrigeration cycle becomes complicated, which leads to an increase in size of the system. In the case of (3) above, the volume of the compression chamber is reduced while the intermediate pressure refrigerant is introduced in the compression portion, and the compression of the refrigerant proceeds. Therefore, the pressure of the refrigerant in the compression chamber increases, the difference from the pressure of the refrigerant before introduction decreases, and a sufficient amount of refrigerant may not be introduced. In this case, it is not possible to sufficiently improve the capacity of the heat pump and the COP.

In Patent Document 1 described above, a wall body stepped portion is formed on the upper edge of the wall body of the scroll compressor, and the wall body has a high portion having a height higher on the center side in the spiral direction than the wall body stepped portion. , A low part with a low height is formed on the outer peripheral end side. In addition, an end plate stepped portion is formed on one side surface of the end plate on which the wall body is erected, and a low surface portion having a lower surface on the center side in the spiral direction than the end plate stepped portion and an outer peripheral end side are formed on one side surface. A high surface portion with a high surface is formed. The end plate stepped portion is formed at a position facing the wall body stepped portion. Further, a fluid supply unit (injection port) for supplying a fluid having a pressure higher than the fluid pressure in the compression chamber to the compression chamber is provided in a region near the end plate stepped portion in the low surface portion.

In the configuration of Patent Document 1, when the compression chamber moving to the center side in the spiral direction passes through the wall body stepped portion and the end plate stepped portion, the volume reduction rate of the compression chamber is moderated or the volume is reduced. Can be increased. Further, the fluid supply portion is provided in the vicinity of the end plate stepped portion on the low surface portion.

In Patent Document 1, it is set as a section in which the reduction rate of the volume of the compression chamber is gradual or a section in which the volume increases from the time when the sealing of the compression chamber is started by the rotation of the swivel scroll member (at the time of the suction deadline). The interval to the section is short. Therefore, when the refrigerant is introduced into the compression chamber, the pressure in the compression chamber rises to the intermediate pressure (injection pressure) at an early stage, so that the period of compression by the pressure after the introduction becomes long, and wasteful compression power is generated.

In addition, since the low part and the high part or the high surface part and the bottom part are switched from the outer peripheral end side to the center side in the spiral direction with the stepped portion of the wall body and the stepped portion of the end plate as a boundary, the volume is increased. The change is only the adjustment of the height and position of the step. Therefore, it is difficult to provide a section in which the volume is substantially constant, and the degree of freedom is low when setting the turning angle range of the section in which the volume is substantially constant.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a scroll fluid machine capable of reliably introducing an intermediate pressure refrigerant during a compression process or an expansion process. ..

In order to solve the above problems, the scroll fluid machine of the present invention employs the following means.
That is, the scroll fluid machine according to the present invention has a first scroll member provided with a spiral first wall body on the first end plate and a second end plate arranged so as to face the first end plate. A second wall body having a spiral shape is provided on the upper surface, and the second wall body is provided with a second scroll member that relatively revolves and turns so as to mesh with the first wall body to form a closed space. After the sealing of the closed space is started, a first region is set in which the volume change of the closed space is gradual or substantially constant, and at least one of the first end plate and the second end plate is in the spiral direction. It has a first wall body inclined portion in which the height of the wall body continuously increases from the outer peripheral side to the inner peripheral side, and at least one of the first wall body and the second wall body is the first wall body. The tooth bottom surface facing the tooth tip of the wall body inclined portion has a first end plate inclined portion that is inclined according to the inclination of the first wall body inclined portion, and the first wall body inclined portion and the first end plate are provided. At least a part of the first region is set depending on the position and shape of the inclined portion, and the first wall body inclined portion or the first end plate inclined portion is the center of the first scroll member or the second scroll member. It is characterized in that it is provided over a region of 20 ° or more around it.

According to this configuration, the first scroll member and the second scroll member relatively revolve and turn, and the second wall body meshes with the first wall body to form a closed space. Then, after the sealing of the closed space is started by the revolution turning motion, a first region is set in which the volume change of the closed space is gradual or substantially constant.

Further, the height of the wall body in the first wall body inclined portion continuously increases from the outer peripheral side to the inner peripheral side in the spiral direction, and in the first end plate inclined portion, the tooth tip of the first wall body inclined portion The tooth bottom surface facing the surface is inclined according to the inclination of the first wall body inclined portion. As a result, during the revolution turning motion, the width of the closed space decreases according to the spiral shape of the wall body, and the height of the closed space, that is, the distance between the facing surfaces between the end plates increases. Therefore, at least a part of the first region where the volume change of the closed space is gradual or substantially constant is set depending on the position and shape of the first wall body inclined portion and the first end plate inclined portion. As the fluid sucked from the outer peripheral side toward the inner peripheral side, the pressure in the closed space is maintained substantially constant in the first region.

Further, the height of the wall body is continuously increased, and the fluid leakage can be reduced as compared with the conventional wall body and the stepped scroll fluid machine having the stepped portion on the tooth bottom. ..

The inclination of the inclined portion of the first wall body and the inclined portion of the first end plate is not limited to the inclined portion connected smoothly, and small steps are connected in a stepped manner, and the entire inclined portion of the first wall body is formed. If you look at it, it includes those that are continuously inclined. The first wall body inclined portion and the first end plate inclined portion may be provided on both sides of the first scroll member and the second scroll member, or may be provided on either side. When the first wall body inclined portion is provided on one wall body and the first end plate inclined portion is provided on the other end plate, the other wall body and one end plate may be flat, or the conventional end plate may be flat. It may be a shape combined with a stepped shape.

In the above invention, the first wall body inclined portion or the first end plate inclined portion may be provided over a region of 180 ° or more around the center of the first scroll member or the second scroll member.

In the above invention, the first end plate or the second end plate is provided with a fluid supply unit that supplies a fluid having a pressure higher than the fluid pressure in the closed space into the closed space, and the fluid supply unit is the said. It may be provided in the first area.

According to this configuration, a fluid supply unit is provided on the first end plate or the second end plate, and the fluid supply unit supplies a fluid having a pressure higher than the fluid pressure in the closed space into the closed space. Since the fluid supply unit is provided in the first region where the volume change of the closed space is gradual or substantially constant, the pressure difference from the fluid to be supplied in the process in which the pressure rise in the closed space is gradual or substantially constant. The fluid can be supplied to the closed space while maintaining the above-predetermined level.

In the above invention, a second region in which the volume of the enclosed space decreases may be set before the first region, and a third region in which the volume of the enclosed space decreases after the first region may be set.

According to this configuration, when the scroll fluid machine is applied as a scroll compressor, a second region in front of the first region is set in front of the first region in which the volume of the enclosed space is reduced. In the region, the pressure in the enclosed space increases as the fluid moves toward the inner circumference. In the first region, the pressure of the fluid whose pressure has increased is maintained substantially constant in the enclosed space as it toward the inner peripheral side. Then, by setting the third region in which the volume of the closed space decreases after the first region, in the third region after the first region, the fluid in the closed space is directed toward the inner peripheral side. The pressure rises again.

In the above invention, at least one of the first wall body and the second wall body has a height of at least one of the first wall body and the second wall body from the outer peripheral side to the inner peripheral side in the spiral direction. It has a second wall body inclined portion that continuously decreases, and at least one of the first end plate and the second end plate has a tooth bottom surface facing the tooth tip of the second wall body inclined portion. It has a second end plate inclined portion that inclines according to the inclination of the wall body inclined portion, and depending on the position and shape of the second wall body inclined portion and the second end plate inclined portion, the second region and the third At least a portion of each of the regions may be set.

According to this configuration, the height of the wall body in the second wall body inclined portion decreases from the outer peripheral side to the inner peripheral side, and in the second end plate inclined portion, it faces the tooth tip of the second wall body inclined portion. The bottom surface of the tooth is inclined according to the inclination of the inclined portion of the second wall body. Therefore, at least a part of each of the second region and the third region where the volume of the enclosed space is reduced is set depending on the position and shape of the second wall body inclined portion and the second end plate inclined portion. As a result, the fluid sucked from the outer peripheral side is not only compressed by the decrease in the width of the closed space according to the spiral shape of the wall body as it goes toward the inner peripheral side, but also the height of the closed space, that is, the edge. Further compression will be achieved by reducing the distance between the facing surfaces between the plates. As a result, three-dimensional compression becomes possible and miniaturization can be realized.

According to the present invention, since a region is set in which the volume change of the closed space is gradual or substantially constant, an intermediate pressure refrigerant can be reliably introduced during the compression process or the expansion process, and the pressure in the closed space can be further increased. The rise can be suppressed. When the scroll fluid machine is applied as a scroll compressor, the compressor efficiency can be improved. In addition, the height of the wall body is continuously increased, and fluid leakage can be reduced as compared with the conventional wall body and the stepped scroll fluid machine having a stepped portion on the tooth bottom. ..

It is a block diagram which shows the refrigerating cycle which concerns on one Embodiment of this invention. It is a partial vertical sectional view which shows the main part of the scroll compressor which concerns on one Embodiment of this invention. It is a vertical cross-sectional view which shows the fixed scroll of the scroll compressor which concerns on one Embodiment of this invention, and is the 3rd-III line arrow view of FIG. It is a top view which shows the fixed scroll which concerns on one Embodiment of this invention. It is a top view which shows the tooth tip and the end plate of the wall body of the fixed scroll which concerns on one Embodiment of this invention. It is a side view which showed the wall body and the end plate of the fixed scroll which concerns on one Embodiment of this invention developed in the spiral direction. It is a vertical sectional view which shows the swivel scroll of the scroll compressor which concerns on one Embodiment of this invention, and is the VII-VII line arrow view of FIG. It is a top view which shows the turning scroll which concerns on one Embodiment of this invention. It is a top view which shows the tooth tip and the end plate of the wall body of the swivel scroll which concerns on one Embodiment of this invention. It is a side view which showed the wall body and the end plate of the swivel scroll which concerns on one Embodiment of this invention developed in the spiral direction. It is a side view which shows the chip seal gap of the scroll compressor which concerns on one Embodiment of this invention, (a) shows the state which the chip seal gap is relatively small, (b) is the state which the chip seal is relatively large. Is shown. It is a graph which shows the relationship between the volume of a compression chamber and a turning angle, and the graph which shows the relationship between the pressure of a compression chamber and a turning angle.

Hereinafter, embodiments according to the present invention will be described with reference to the drawings.
As shown in FIG. 1, the refrigerating cycle 10 decompresses the scroll compressor 1 that compresses the refrigerant (fluid), the condenser 2 that dissipates the heat of the compressed refrigerant to the outside, and the refrigerant that flows out from the condenser 2. A first expansion valve 3 provided on the high-pressure side, an economizer (gas-liquid separator) 4 for separating the decompressed refrigerant into a liquid refrigerant and a gas refrigerant, and a second provided on the low-pressure side for further depressurizing the liquid refrigerant. It includes an expansion valve 5, an evaporator 6 that absorbs heat from the decompressed refrigerant, an injection flow path 7 that guides the gas refrigerant from the economizer 4 to the scroll compressor 1, and the like.

The scroll compressor 1 is a closed type compressor, and as shown in FIG. 2, a housing 11 having a closed space inside and a scroll compressor arranged in the housing 11 and compressing a refrigerant taken into the closed space are compressed. The main elements are a mechanism 12, a rotation shaft that transmits a rotational force to the scroll compression mechanism 12, and an electric motor that revolves and turns the scroll scroll 19 of the scroll compression mechanism 12 via the rotation shaft.

The bottom of the housing 11 is sealed by a lower cover, and the upper part of the lower cover is provided with a cylindrical intermediate cover 13 that is long in the vertical direction. A discharge cover 14 and an upper cover 15 are provided on the upper portion of the intermediate cover 13, and the housing 11 is sealed, and a compressed high-pressure gas is discharged between the discharge cover 14 and the upper cover 15. The chamber 16 is formed.

A scroll compression mechanism 12 is incorporated in the housing 11, and an electric motor including a stator and a rotor is installed below the scroll compression mechanism 12. The electric motor is incorporated by fixing the stator to the housing 11, and the rotating shaft is fixed to the rotor.

The scroll compression mechanism 12 includes a fixed scroll 18 that is fixedly installed with respect to the housing 11, and a swivel scroll 19 that is slidably supported and meshes with the fixed scroll 18 to form a compression chamber 20.

A suction port (not shown) for sucking the refrigerant is formed on the side surface of the housing 11 so as to communicate with the closed space, and the top side of the upper cover 15 communicates with the discharge chamber 16 and is compressed. A discharge port 15a for discharging the generated refrigerant gas is formed.

The scroll compression mechanism 12 sucks the refrigerant gas sucked into the housing 11 through the suction pipe and the suction port into the compression chamber 20 from the suction port 21 on the outer peripheral side which is open to the inside of the housing 11 and compresses the refrigerant gas. do. The compressed refrigerant gas is discharged into the discharge chamber 16 through the discharge port 22 provided in the center of the fixed scroll 18 and the discharge port 23 provided in the discharge cover 14, and further to the upper cover 15. It is provided and is sent out to the outside of the compressor via a discharge pipe 24 that communicates with the discharge chamber 16.

Further, the discharge cover 14 is provided with an injection pipe 25 that introduces an intermediate pressure refrigerant from the outside into the compression chamber 20 of the scroll compression mechanism 12 so as to penetrate the upper cover 15. Refrigerant is supplied to the compression chamber 20 via the injection pipe 25 and the injection port (fluid supply unit) 26.

The reed valve 27 is a thin plate-shaped member, which is provided at the outlet portion of the discharge port 22 and opens and closes the discharge port 22. The reed valve 27 regulates the flow of refrigerant in only one direction. By providing the reed valve 27, the refrigerant flows from the compression chamber 20 to the discharge chamber 16 side.

As shown in FIG. 2, the fixed scroll 18 has a substantially disk-shaped end plate (first end plate) 18a and a spiral wall body (first end plate) erected on one side surface of the end plate 18a. 1 wall body) 18b and is provided. As shown in FIG. 2, the swirl scroll 19 has a substantially disk-shaped end plate (second end plate) 19a and a spiral wall body (first) erected on one side surface of the end plate 19a. It is equipped with a two-walled body) 19b. The spiral shape of each wall body 18b, 19b is defined by using, for example, an involute curve or an Archimedes curve.

The fixed scroll 18 and the swivel scroll 19 are engaged with each other by separating the centers O1 and O2 by the swivel radius ρ and shifting the phases of the wall bodies 18b and 19b by 180 °, and the tooth tips of the wall bodies 18b and 19b of both scrolls 18 and 19. It is assembled so as to have a slight height clearance (tip clearance) between the tooth bottom and the tooth bottom at room temperature. As a result, between the scrolls 18 and 19, a plurality of pairs of compression chambers 20 formed by being surrounded by the end plates 18a and 19a and the wall bodies 18b and 19b are formed symmetrically with respect to the scroll center. The swivel scroll 19 revolves around the fixed scroll 18 by a rotation prevention mechanism such as an old dam ring (not shown).

As shown in FIG. 2, the distance L between the facing surfaces between the two end plates 18a and 19a facing each other is continuously decreased or increased from the outer peripheral side to the inner peripheral side of the spiral wall bodies 18b and 19b. , The inclination of the tooth tip in the wall bodies 18b and 19b and the inclination of the tooth bottom in the end plates 18a and 19a are set.

As shown in FIGS. 3, 5 and 6, the wall body 18b of the fixed scroll 18 has a wall body flat portion 18b1, a second wall body inclined portion 18b2, and a wall body flat portion from the outer peripheral side to the inner peripheral side. A portion 18b3, a first wall body inclined portion 18b4, a wall body flat portion 18b5, a second wall body inclined portion 18b6, and a wall body flat portion 18b7 are provided in this order. Further, as shown in FIGS. 3, 4, and 6, the tooth bottom surface of the fixed scroll 18 has an end plate flat portion 18a1, a second end plate inclined portion 18a2, and an end plate from the outer peripheral side to the inner peripheral side. The flat portion 18a3, the first end plate inclined portion 18a4, the end plate flat portion 18a5, the second end plate inclined portion 18a6, and the end plate flat portion 18a7 are provided in this order.

As shown in FIGS. 7, 9 and 10, the wall body 19b of the swivel scroll 19 has a wall body flat portion 19b1, a second wall body inclined portion 19b2, and a wall body flat portion from the outer peripheral side to the inner peripheral side. A portion 19b3, a first wall body inclined portion 19b4, a wall body flat portion 19b5, a second wall body inclined portion 19b6, and a wall body flat portion 19b7 are provided in this order. Further, as shown in FIGS. 7, 8 and 10, the tooth bottom surface of the swivel scroll 19 has an end plate flat portion 19a1, a second end plate inclined portion 19a2, and an end plate from the outer peripheral side to the inner peripheral side. The flat portion 19a3, the first end plate inclined portion 19a4, the end plate flat portion 19a5, the second end plate inclined portion 19a6, and the end plate flat portion 19a7 are provided in this order.

The heights of the wall flat portions 19b1, 19b3, 19b5, 19b7 provided on the wall body 19b of the swivel scroll 19 are constant from the outer peripheral side to the inner peripheral side, respectively. That is, the dimension in the axial direction passing through the center O2 (see FIG. 2) of the swivel scroll 19 is constant. Hereinafter, the height of the wall body and the tooth bottom means the dimension in the axial direction passing through the centers O1 and O2.

As shown in FIG. 10, flat wall portions 19b1 and 19b7 having a constant height are provided on the outermost peripheral side and the innermost peripheral side of the wall body 19b of the swivel scroll 19, respectively. .. As shown in FIG. 8, these flat wall portions 19b1 and 19b7 cover a region of 180 ° (for example, 180 ° or more and 360 ° or less, preferably 210 ° or less) around the center O2 (see FIG. 2) of the swivel scroll 19. It is provided.

Similarly, the tooth bottoms of the end plates 19a of the swivel scroll 19 are provided with flat end plate portions 19a1 and 19a7 having a constant height. These flat end plate portions 19a1 and 19a7 are also provided around the center O2 of the swivel scroll 19 over a region of 180 ° (for example, 180 ° or more and 360 ° or less, preferably 210 ° or less).

As shown in FIG. 4, the fixed scroll 18 is also provided with the wall flat portions 18b1, 18b7 and the end plate flat portions 18a1, 18a7, similarly to the swivel scroll 19. The flat wall portions 18b1, 18b7 and the flat end plate portions 18a1, 18a7 are also provided over a region of 180 ° (for example, 180 ° or more and 360 ° or less, preferably 210 ° or less) around the center O1 of the fixed scroll 18. ..

As shown in FIG. 10, the height of the first wall body inclined portion 19b4 provided on the wall body 19b of the swivel scroll 19 continuously increases from the outer peripheral side to the inner peripheral side. As shown in FIG. 6, the tooth bottom surface on the end plate 18a of the fixed scroll 18 on which the tooth tips of the first wall body inclined portion 19b4 face each other is inclined according to the inclination of the first wall body inclined portion 19b4. 1 End plate inclined portion 18a4 is provided. Similarly, as shown in FIG. 6, the first wall body inclined portion 18b4 provided on the wall body 18b of the fixed scroll 18 also continuously increases from the outer peripheral side to the inner peripheral side, and as shown in FIG. In addition, on the tooth bottom surface on the end plate 19a of the swivel scroll 19 facing the tooth tip of the first wall body inclined portion 18b4, the first end plate inclined portion inclined according to the inclination of the first wall body inclined portion 18b4. 19a4 is provided. The length of the first wall body inclined portion 18b4, 19b4 and the first end plate inclined portion 18a4, 19a4 in the spiral direction is set to be 20 ° or more, preferably 180 ° or more around the centers O1 and O2. .. Further, the length of the first wall body inclined portion 18b4, 19b4 and the first end plate inclined portion 18a4, 19a4 in the spiral direction may be set to a length corresponding to the vicinity of 360 ° around the centers O1 and O2.

As a result, the width of the compression chamber 20 decreases according to the spiral shape of the wall bodies 18b and 19b during the revolution rotation motion of the swivel scroll 19, and the height of the compression chamber 20, that is, the opposition between the end plates 18a and 19a. The face-to-face distance increases. Therefore, depending on the position and shape of the first wall body inclined portion 18b4, 19b4 and the first end plate inclined portion 18a4, 19a4 in the spiral direction (for example, the inclination angle or the length in the spiral direction), the volume change of the compression chamber 20 is gradual or At least a part of the first region that is substantially constant is set. As the fluid sucked from the suction port 21 on the outer peripheral side goes toward the inner peripheral side, the pressure in the compression chamber 20 is maintained substantially constant in the first region.

The first region may be set by providing only one first wall body inclined portion 18b4, 19b4 or the first end plate inclined portion 18a4, 19a4 over the spiral direction, or a plurality of first walls. It may be set by arranging the body inclined portions 18b4, 19b4 or the first end plate inclined portions 18a4, 19a4 in series. When a plurality of first wall body inclined portions 18b4, 19b4 or first end plate inclined portions 18a4, 19a4 are arranged in series, the respective inclined angles may be different, or the wall body flat portion or the end plate flat portion may be located between them. It is realized by providing.

The end plate 18a of the fixed scroll 18 is provided with an injection port 26 for supplying a refrigerant having a pressure higher than the fluid pressure in the compression chamber 20 into the compression chamber 20. When the swivel scroll 19 revolves and swivels, the tooth tips of the wall body 19b of the swivel scroll 19 move onto the injection port 26 and both overlap, the communication between the compression chamber 20 and the injection port 26 is closed. On the contrary, when the tooth tip of the wall body 19b of the swivel scroll 19 moves from above the injection port 26 and the injection port 26 opens, the compression chamber 20 and the injection port 26 communicate with each other. The injection port 26 is provided in the first region where the volume change of the compression chamber 20 described above is gradual or substantially constant. Thereby, in a process in which the pressure change in the compression chamber 20 is gradual or substantially constant, the refrigerant can be supplied to the compression chamber 20 while maintaining the pressure difference with the refrigerant supplied from the injection port 26 at a predetermined value or more. In the first region, the injection step of the intermediate pressure refrigerant is performed.

As described above, the injection port 26 is repeatedly opened and closed (communication and non-communication) by the cycle (360 ° cycle) of the revolution rotation motion of the swivel scroll 19. The period in which the compression chamber 20 and the injection port 26 communicate with each other is a period excluding the period in which the compression chamber 20 and the injection port 26 do not communicate with each other from the cycle of the revolution turning motion, and is less than 360 °. It is desirable that the section in which the compression chamber 20 and the injection port 26 communicate with each other is a first region in which the volume change of the compression chamber 20 is gradual or substantially constant. The first wall body inclined portion 18b4, 19b4 and the first end plate inclined portion 18a4, 19a4 are provided around the center O1, O2 by 20 ° or more, preferably 180 ° or more, or over a region near 360 °. The necessary and sufficient first area can be set.

The height of the second wall body inclined portions 19b2 and 19b6 provided on the wall body 19b of the swivel scroll 19 continuously decreases from the outer peripheral side to the inner peripheral side. The tooth bottom surface on the end plate 18a of the fixed scroll 18 with the tooth tips of the second wall body inclined portions 19b2, 19b6 facing each other has a second end plate inclined according to the inclination of the second wall body inclined portions 19b2, 19b6. Inclined portions 18a2 and 18a6 are provided. Similarly, the second wall body inclined portions 18b2, 18b6 provided on the wall body 18b of the fixed scroll 18 also continuously decrease from the outer peripheral side to the inner peripheral side, and the second wall body inclined portions 18b2, 18b6 The tooth bottom surface on the end plate 19a of the swivel scroll 19 facing the tooth tip is provided with the second end plate inclined portions 19a2, 19a6 which are inclined according to the inclination of the second wall body inclined portions 18b2, 18b6. ..

As a result, the width of the compression chamber 20 decreases according to the spiral shape of the wall bodies 18b and 19b during the revolution rotation motion of the swivel scroll 19, and the height of the compression chamber 20, that is, the opposition between the end plates 18a and 19a. The face-to-face distance is reduced. Therefore, it is compressed by the position and shape in the spiral direction (for example, the tilt angle and the length in the spiral direction) of the second wall body inclined portion 18b2, 18b6, 19b2, 19b6 and the second end plate inclined portion 18a2, 18a6, 19a2, 19a6. At least a part of each of the second region and the third region where the volume of the chamber 20 is reduced is set. The refrigerant sucked from the suction port 21 on the outer peripheral side is not only compressed by the reduction in the width of the compression chamber 20 according to the spiral shape of the wall bodies 18b and 19b as it goes toward the inner peripheral side, but also in the compression chamber 20. Further compression is achieved by reducing the height, that is, the distance between the facing surfaces between the end plates 18a and 19a. As a result, three-dimensional compression becomes possible and miniaturization can be realized.

The second region in which the volume of the compression chamber 20 is reduced is set before the first region in the moving direction of the compression chamber 20 accompanying the revolution swiveling motion of the swivel scroll 19, and the third region is set in the moving direction of the compression chamber 20. It is set after the first area. The second region is a region from the time when the wall bodies 18b and 19b mesh with each other on the outer peripheral side to form the compression chamber 20 and close the space until the first region starts. The third region is a region from the end of the first region to the end of the discharge of the compressed refrigerant from the discharge port 22.

By setting the second region in which the volume of the compression chamber 20 decreases in front of the first region, in the second region before the first region, the refrigerant in the compression chamber 20 is directed toward the inner peripheral side. The pressure rises. In the first region, the refrigerant whose pressure has increased tends toward the inner peripheral side, but the pressure in the compression chamber 20 is maintained substantially constant. Then, by setting the third region in which the volume of the compression chamber 20 decreases after the first region, the compression chamber 20 is set in the third region after the first region as the refrigerant moves toward the inner peripheral side. The pressure inside rises again. In the second region, a low-stage compression step is performed, and in the third region, a high-stage compression step is performed. The gradual or substantially constant volume change of the compression chamber 20 in the first region means that the volume change of the compression chamber 20 in the second region or the third region is gradual or substantially constant.

From the above, a two-stage compression refrigeration cycle is realized in which the refrigerant is introduced from the economizer 4 into the middle of the compression process of the scroll compression mechanism 12 via the injection flow path 7 and the injection port 26. Further, between the second region and the third region where the volume of the compression chamber 20 is reduced, a first region is provided in which the volume change of the compression chamber 20 is gradual or substantially constant, and only one scroll compression mechanism 12 is provided. In the single-stage scroll compressor 1, an intermediate pressure refrigerant can be introduced from the economizer 4 during the compression process of the scroll compression mechanism 12.

The first wall body inclined portion 18b4, 19b4, the first end plate inclined portion 18a4, 19a4, the second wall body inclined portion 18b2, 18b6, 19b2, 19b6 and the second end plate inclined portion 18a2, 18a6 in the present embodiment. , 19a2,19a6 are not limited to smoothly connected slopes, but small steps that inevitably occur during manufacturing by machining or laminated molding (AM) are connected in a staircase pattern. Including those that are continuously inclined when looking at the inclined part as a whole. However, it does not include a large step such as a so-called stepped scroll.

The first wall body inclined portion 18b4, 19b4, the first end plate inclined portion 18a4, 19a4, the second wall body inclined portion 18b2, 18b6, 19b2, 19b6 and the second end plate inclined portion 18a2, 18a6, 19a2, 19a6 A coating may be applied. Examples of the coating include manganese phosphate treatment and nickel phosphorus plating.

As shown in FIGS. 6 and 10, the tooth tip heights at the outer peripheral side end portions 18b8, 19b8 of the second wall body inclined portions 18b2, 19b2 arranged on the outer peripheral side of the first wall body inclined portions 18b4, 19b4 are , It is preferable that the height is the same as the tooth tip height at the inner peripheral side end portions 18b9, 19b9 of the first wall body inclined portion 18b4, 19b4. Thereby, the measurement can be performed at one end 18b8, 19b8 and the other end 18b9, 19b9 with the first wall inclined portion 18b4, 19b4 and the second wall inclined portion 18b2, 19b2 sandwiched between them. , The fixed scroll 18 or the swivel scroll 19 can be suitably measured.

As for the end plates 18a and 19a, as shown in FIGS. 6 and 10, the outer peripheral side end portions 18a8 of the second end plate inclined portions 18a2 and 19a2 arranged on the outer peripheral side of the first end plate inclined portions 18a4 and 19a4. , 19a8, the tooth bottom height may be the same as the tooth bottom height at the inner peripheral side end portions 18a9, 19a9 of the first end plate inclined portions 18a4, 19a4. As a result, the measurement is performed at one end 18a8, 19a8 and the other end 18a9, 19a9 with the first end plate inclined portion 18a4, 19a4 and the second end plate inclined portion 18a2, 19a2 sandwiched between them. The dimensions of the fixed scroll 18 or the swivel scroll 19 can be suitably measured.

A tip seal is provided at the tooth tip of the wall body 18b of the fixed scroll 18. The tip seal is made of resin and comes into contact with the tooth bottom of the end plate 19a of the facing swivel scroll 19 to seal the fluid. The tip seal is housed in a tip seal groove 18d formed in the circumferential direction at the tooth tip of the wall body 18b. Similarly, a tip seal groove 19d is formed on the tooth tip of the wall body 19b of the swivel scroll 19, and a tip seal is provided in the tip seal groove 19d.

When both scrolls 18 and 19 perform a relative revolutionary turning motion, the positions of the tooth tip and the tooth bottom are relatively displaced by the turning diameter (turning radius ρ × 2). Due to this misalignment between the tooth tip and the tooth bottom, the tip clearance between the tooth tip and the tooth bottom changes in the inclined portion. For example, FIG. 11A shows that the tip clearance T is small, and FIG. 11B shows that the tip clearance T is large. Even if the tip clearance T changes due to the turning motion, the tip seal 28 is pressed from the back surface by the compressive fluid toward the tooth bottom side of the end plate 19a, so that the tip seal 28 can be subsequently sealed.

The scroll compressor 1 described above operates as follows.
The swivel scroll 19 revolves around the fixed scroll 18 by a drive source such as an electric motor (not shown). As a result, the fluid is sucked from the outer peripheral side of the scrolls 18 and 19, and the refrigerant is taken into the compression chamber 20 surrounded by the wall bodies 18b and 19b and the end plates 18a and 19a.

First, the walls 18b and 19b are engaged with each other on the outer peripheral side to form a compression chamber 20 and closed, and then in the second region, the refrigerant in the compression chamber 20 is compressed as it moves from the outer peripheral side to the inner peripheral side. Then, as shown in FIG. 12, the pressure in the compression chamber 20 rises. The compressed refrigerant moves to the first region, and in the first region, the refrigerant moves toward the inner peripheral side. Then, the intermediate pressure refrigerant is supplied from the economizer 4 to the compression chamber 20 via the injection pipe 25 and the injection port (fluid supply unit) 26. In the first region, as shown in FIG. 12, the pressure change in the compression chamber 20 is gradual or substantially constant, and the fluid is compressed in the compression chamber while maintaining the pressure difference with the refrigerant supplied from the economizer 4 at a predetermined value or more. Can be supplied to 20.

After that, the refrigerant moves to the third region, and in the third region, the refrigerant is compressed toward the inner peripheral side, and as shown in FIG. 12, the pressure in the compression chamber 20 rises again. The compressed refrigerant is finally discharged from the discharge port 22 formed in the fixed scroll 18.

As described above, according to the scroll compressor 1 of the present embodiment, the following functions and effects are obtained.
Since the distance between the facing surfaces between the end plates 18a and 19a is provided with an inclination that continuously decreases from the outer peripheral side to the inner peripheral side of the wall bodies 18b and 19b, three-dimensional compression becomes possible and miniaturization is possible. It can be realized.

Since it was decided to provide an inclination in which the distance between the facing surfaces between the end plates 18a and 19a continuously increases from the outer peripheral side to the inner peripheral side of the wall bodies 18b and 19b, after the sealing of the compression chamber 20 is started. A first region is set in which the volume change of the compression chamber 20 is gradual or substantially constant. Since the injection port 26 is provided in the first region, the refrigerant is compressed in the compression chamber 20 while the pressure difference with the supplied refrigerant is maintained at a predetermined level or more in a process in which the pressure change in the compression chamber 20 is gradual or substantially constant. Can be reliably supplied to 20.

Since the distance between the facing surfaces between the end plates 18a and 19a is provided with an inclination that continuously decreases from the outer peripheral side to the inner peripheral side of the wall bodies 18b and 19b, three-dimensional compression becomes possible and miniaturization is possible. It can be realized.

Further, the inclined portion is continuously increased or decreased, and the fluid leakage can be reduced as compared with the conventional stepped scroll fluid machine in which the step portion is provided on the wall body and the tooth bottom.

Since the tip seal 28 is provided at the tooth tip of each of the wall bodies 18b and 19b, even if the tip clearance T (see FIG. 11) between the tooth tip and the tooth bottom in the inclined portion changes according to the turning motion. , The tip seal can be made to follow, and fluid leakage can be suppressed.

It was decided to coat the wall bodies 18b, 19b and / or the end plates 18a, 19a. As a result, it is possible to compensate for the processing variation of the inclined portion where it is difficult to obtain the processing accuracy by the film thickness of the coating, and it is possible to further suppress the fluid leakage.

It was decided to provide the wall body flat portions 18b1, 18b7, 19b1, 19b7 and the end plate flat portions 18a1, 18a7, 19a1, 19a7 on the outermost peripheral portion and the innermost peripheral portion of the wall bodies 18b, 19b and the end plates 18a, 19a. As a result, if the tooth tips of the wall body are inclined, it is possible to avoid that it is difficult to set the measurement point and improve the measurement accuracy, and the shape measurement can be performed with high accuracy. Then, it becomes easy to manage the dimensions of the scroll shape and the chip clearance.

By providing the wall flat portions 18b1, 18b7, 19b1, 19b7 and the end plate flat portions 18a1, 18a7, 19a1, 19a7 over a 180 ° region, the flat portions on both sides of the scrolls 18 and 19 sandwiching the centers 01 and 02. Measurements can be made. As a result, the shape and dimensions of the fixed scroll 18 or the swivel scroll 19 can be suitably performed.
Further, if the range of the flat portion greatly exceeds 180 °, the region of the inclined portion decreases and the inclination φ of the inclined portion becomes large. When the inclination φ becomes large, the amount of change in the tip clearance T due to the turning diameter during the revolution turning motion becomes large, and the fluid leakage may become large. Therefore, the flat wall portions 18b1, 18b7, 19b1, 19b7 and the flat end plate portions 18a1, 18a7, 19a1, 19a7 have a 180 ° region. However, this 180 ° is not strict, and an angle slightly exceeding 180 ° (for example, about 30 °) is allowed as long as the fluid leakage does not increase.

The inclination φ of the inclined portion is made constant with respect to the circumferential direction in which the spiral wall bodies 18b and 19b extend. As a result, the tip clearance T due to the turning diameter during the revolution turning motion can be made equal at each position of the inclined portion, and fluid leakage can be suppressed.

In the present embodiment, the first wall body inclined portion 18b4, 19b4, the first end plate inclined portion 18a4, 19a4, the second wall body inclined portion 18b2, 18b6, 19b2, 19b6 and the second end plate inclined portion 18a2, 18a6, 19a2 , 19a6 are provided on both scrolls 18 and 19, but may be provided on either one.
Specifically, one wall body (for example, the wall body 19b of the swivel scroll 19) is provided with the first wall body inclined portion 19b4 and the second wall body inclined portion 19b2, 19b6, and the other end plate (for example, the fixed scroll 18) is provided. When the first end plate inclined portion 19a4 and the second end plate inclined portion 19a2, 19a6 are provided on the end plate 18a), the other wall body 18b and one end plate 19a are made flat.
Further, a shape combined with the conventional stepped shape, that is, the end plate 18a of the fixed scroll 18 is provided with the first end plate inclined portion 18a4 and the second end plate inclined portions 18a2, 18a6, while the end plate of the swivel scroll 19 is provided. It may be combined with the shape provided with the step portion in 19a.

In the present embodiment, the flat wall portions 18b1, 18b7, 19b1, 19b7 and the flat end plate portions 18a1, 18a7, 19a1, 19a7 are provided, but the flat portions on the inner peripheral side and / or the outer peripheral side are omitted. The second wall body inclined portion 18b2, 19b2 may be provided so as to extend over the entire wall body 18b, 19b.

Although described as a scroll compressor in the present embodiment, the present invention can also be applied to a scroll expander used as an expander.

1: Scroll compressor 2: Condenser 3: First expansion valve 4: Economizer 5: Second expansion valve 6: Evaporator 7: Injection flow path 10: Refrigeration cycle 11: Housing 12: Scroll compression mechanism 13: Intermediate cover 14 : Discharge cover 15: Top cover 15a: Discharge port 16: Discharge chamber 18: Fixed scroll 18a: End plate 18a1: End plate flat portion 18a2: Second end plate inclined portion 18a3: End plate flat portion 18a4: First end plate inclination Part 18a5: End plate flat portion 18a6: Second end plate inclined portion 18a7: End plate flat portion 18a8: Outer peripheral side end portion 18a9: Inner peripheral side end portion 18b: Wall body 18b1: Wall body flat portion 18b2: Second wall body Inclined portion 18b3: Wall body flat portion 18b4: First wall body inclined portion 18b5: Wall body flat portion 18b6: Second wall body inclined portion 18b7: Wall body flat portion 18b8: Outer peripheral side end portion 18b9: Inner peripheral side end portion 18d : Chip seal groove 19: Swirling scroll 19a: End plate 19a1: End plate flat portion 19a2: Second end plate inclined portion 19a3: End plate flat portion 19a4: First end plate inclined portion 19a5: End plate flat portion 19a6: Second End plate inclined portion 19a7: End plate flat portion 19a8: Outer peripheral side end portion 19a9: Inner peripheral side end portion 19b: Wall body 19b1: Wall body flat portion 19b2: Second wall body inclined portion 19b3: Wall body flat portion 19b4: First 1 wall body inclined portion 19b5: wall body flat portion 19b6: second wall body inclined portion 19b7: wall body flat portion 19b8: outer peripheral side end portion 19b9: inner peripheral side end portion 20: compression chamber 21: suction port 22: discharge port 23: Discharge port 24: Discharge pipe 25: Injection pipe 26: Injection port 27: Reed valve 28: Chip seal

Claims (5)

A first scroll member provided with a spiral first wall on the first end plate, and
A spiral second wall body is provided on the second end plate arranged so as to face the first end plate, and the second wall body meshes with the first wall body to form a closed space. The second scroll member that relatively revolves and turns, and
Equipped with
After the sealing of the closed space is started, a first region is set in which the volume change of the closed space is gradual or substantially constant.
At least one of the first wall body and the second wall body has a first wall body inclined portion in which the height of the wall body continuously increases from the outer peripheral side to the inner peripheral side in the spiral direction.
At least one of the first end plate and the second end plate is a first end plate in which the tooth bottom surface facing the tooth tip of the first wall inclined portion is inclined according to the inclination of the first wall inclined portion. Has an inclined part,
At least a part of the first region is set by the position and shape of the first wall body inclined portion and the first end plate inclined portion.
The scroll fluid machine is characterized in that the inclined portion of the first wall body or the inclined portion of the first end plate is provided over a region of 20 ° or more around the center of the first scroll member or the second scroll member. .. Claim 1 is characterized in that the inclined portion of the first wall body or the inclined portion of the first end plate is provided over a region of 180 ° or more around the center of the first scroll member or the second scroll member. Scroll fluid machine described in. The first end plate or the second end plate is provided with a fluid supply unit that supplies a fluid having a pressure higher than the fluid pressure in the closed space into the closed space.
The scroll fluid machine according to claim 1 or 2, wherein the fluid supply unit is provided in the first region. Claim 1 is characterized in that a second region in which the volume of the closed space is reduced is set before the first region, and a third region in which the volume of the closed space is reduced is set after the first region. The scroll fluid machine according to any one of 3 to 3. In at least one of the first wall body and the second wall body, the height of at least one of the first wall body and the second wall body continuously decreases from the outer peripheral side to the inner peripheral side in the spiral direction. Has a second wall sloping part to
At least one of the first end plate and the second end plate is a second end plate whose bottom surface facing the tooth tip of the second wall inclined portion is inclined according to the inclination of the second wall inclined portion. Has an inclined part,
4. The fourth aspect of the present invention is characterized in that at least a part of each of the second region and the third region is set depending on the position and shape of the second wall body inclined portion and the second end plate inclined portion. Described scroll fluid machine.

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