JP2019143546A - Scroll fluid machine - Google Patents

Abstract

To provide a scroll fluid machine capable of reliably introducing intermediate-pressure refrigerant in the middle of a compression stroke to improve compressor efficiency.SOLUTION: A scroll compressor 1 includes a fixed scroll 18, and a turning scroll. In an end plate, a first bypass port 31 is provided ahead of an injection port 26 in the direction of the movement of a compression chamber accompanying revolution turning motion for discharging refrigerant compressed in the compression chamber and having at least a predetermined pressure to the outside of the compression chamber.SELECTED DRAWING: Figure 13

Description

  The present invention relates to a scroll fluid machine.

  2. Description of the Related Art Generally, a scroll fluid machine is known in which a fixed scroll member provided with a spiral wall on an end plate and a turning scroll member are engaged with each other, and a revolution turning motion is performed to compress or expand a fluid. Among scroll fluid machines, a scroll compressor is a device that compresses a refrigerant circulating in a refrigeration cycle applied to, for example, an air conditioner.

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

JP 2006-31898 A

  In order to realize the above-described 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 compressor and a low-stage compressor are accommodated in a single compressor, an intermediate pressure is applied between the discharge side of the low-stage compressor and the suction side of the high-stage compressor. Introduce refrigerant. (2) Two single-stage compressors having only one compressor 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 section, an intermediate pressure refrigerant is introduced during the compression process of the compression section.

  In the case of the above (1), a two-stage compressor that accommodates the high-stage compression section and the low-stage compression section is necessary, and the structure of the single compressor becomes complicated. In the case of (2), since two compressors are required, the system constituting the refrigeration cycle becomes complicated, resulting in an increase in the size of the system. In the case of the above (3), the volume in the compression chamber decreases while the intermediate pressure refrigerant is being introduced into the compression section, and the compression of the refrigerant proceeds. For this reason, 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 heat pump capacity and COP.

  In Patent Literature 1 described above, a wall stepped portion is formed at the upper edge of the wall of the scroll compressor, and the wall has a higher portion on the center side in the spiral direction than the wall stepped portion. A low portion having a low height is formed on the outer peripheral end side. Further, an end plate stepped portion is formed on one side surface of the end plate on which the wall body is erected, and a lower surface portion having a lower surface on the center side in the spiral direction than the end plate stepped portion on one side surface, the outer peripheral end side A high surface portion having a high surface is formed. The end plate stepped portion is formed at a position facing the wall body stepped portion. In addition, a fluid supply part (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 toward the center side in the spiral direction passes through the wall stepped portion and the end plate stepped portion, the volume reduction rate of the compression chamber is moderated or the volume is increased. Can be increased. Moreover, the fluid supply part is provided in the vicinity region of the end plate stepped part in the low surface part.

  In the single-stage compressor having only one compression section as in (3) above, when the intermediate pressure refrigerant is introduced during the compression process of the compression section, the low-stage compression process proceeds and the pressure in the compression chamber is increased. May exceed the intermediate pressure. In this case, a predetermined amount of fluid cannot be supplied into the compression chamber via the fluid supply unit.

  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 fluid during a compression process or an expansion stroke. .

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 includes a first scroll member in which a spiral first wall body is provided on a first end plate, and a second end plate disposed so as to face the first end plate. A second scroll member that is provided with a spiral second wall body and relatively revolves so that the second wall body meshes with the first wall body to form a sealed space; The first end plate or the second end plate is a fluid that is compressed in the sealed space and has a pressure equal to or higher than a predetermined level before the fluid supply unit in the moving direction of the sealed space accompanying the revolving and turning motion. A first fluid discharge part is provided for discharging the gas to the outside of the sealed space.

  According to this configuration, the first scroll member and the second scroll member relatively revolve and rotate, and the second wall body meshes with the first wall body to form a sealed space. A fluid supply unit is provided in 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 sealed space into the compressor chamber. In addition, the first end plate or the second end plate is provided with a first fluid discharge portion in front of the fluid supply portion in the moving direction of the sealed space accompanying the revolution turning motion, and the first fluid discharge portion is sealed. A fluid compressed in the space and having a pressure higher than a predetermined pressure is discharged to the outside of the sealed space. As a result, it is possible to prevent the sealed space from becoming a pressure higher than a predetermined pressure, for example, higher than the high-pressure fluid supplied through the fluid supply unit, before the fluid supply unit. Thus, a predetermined amount of fluid can be supplied into the sealed space.

  In the above invention, the outlet of the first fluid discharge part may be formed to open in the same space as the outlet of the fluid supply part.

  According to this configuration, the fluid discharged from the first fluid discharge unit is guided to the same space as the outlet of the fluid supply unit, and is supplied again into the sealed space together with the fluid supplied from the fluid supply unit.

  In the above invention, the first end plate or the second end plate is compressed in the sealed space after the fluid supply unit in the moving direction of the sealed space accompanying the revolving swivel motion, and more than a predetermined value. A second fluid discharge unit that discharges a fluid having pressure to the outside of the sealed space may be provided.

  According to this configuration, the first end plate or the second end plate is provided with the second fluid discharge portion after the fluid supply portion in the moving direction of the sealed space accompanying the revolution turning motion, and the second fluid discharge portion Discharges the fluid compressed in the sealed space and having a pressure higher than a predetermined value to the outside of the sealed space. Thereby, it is possible to prevent the sealed space from becoming higher than a predetermined pressure, for example, a fluid discharged through the discharge port, higher than a predetermined pressure after the fluid supply unit.

  In the above invention, the outlet of the second fluid discharge part may be formed to open in the same space as the discharge port provided on the most downstream side of the sealed space.

  According to this configuration, the fluid discharged from the second fluid discharge portion is guided to the same space as the discharge port provided on the most downstream side of the sealed space, and discharged to the outside together with the fluid discharged from the discharge port. .

  In the above invention, after the sealing of the sealed space is started, a first region in which the volume change of the sealed space becomes moderate or substantially constant, and a second volume in which the volume of the sealed space decreases before the first region. A region may be set, the fluid supply unit may be provided in the first region, and the first fluid discharge unit may be provided in the second region.

According to this configuration, the first region in which the volume change of the sealed space becomes gentle or substantially constant after the sealed space is started by the revolving and turning motion is set. In addition, since the second region in which the volume of the sealed space decreases is set in front of the first region, in the second region in front of the first region, as the fluid moves toward the inner peripheral side, Pressure increases. In the first region, the fluid whose pressure has increased is maintained at a substantially constant pressure in the sealed space as it moves toward the inner peripheral side.
By providing the first fluid discharge portion in the second region, the sealed space has a higher pressure than the high-pressure fluid supplied through the fluid supply portion in the second region before the fluid supply portion. In the first region, a predetermined amount of fluid can be supplied into the sealed space via the fluid supply unit.

  In the above invention, a third region in which the volume of the sealed space decreases after the first region may be set, and the second fluid discharge unit may be provided in the third region.

According to this configuration, the third region in which the volume of the sealed space decreases is set after the first region, so that the fluid moves toward the inner peripheral side in the third region after the first region. The pressure in the enclosed space rises again.
By providing the second fluid discharge part in the third region, it is possible to prevent the fluid discharged through the discharge port from becoming a pressure higher than a predetermined level in the third region after the fluid supply unit. .

  In the above invention, at least one of the first wall body and the second wall body is a first wall body inclined portion in which the height of the wall body continuously increases from the outer peripheral side in the spiral direction toward the inner peripheral side. And at least one of the first end plate and the second end plate has a tooth bottom surface facing a tooth tip of the first wall inclined portion inclined according to the inclination of the first wall inclined portion. It has a 1st end plate inclination part, and at least one part of the 1st field may be set by the position and shape of the 1st wall body inclination part and the 1st end plate inclination part.

  According to this configuration, 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 the first wall slope in the first end plate inclined portion. The tooth bottom surface facing the tooth tip of the portion is inclined according to the inclination of the first wall inclined portion. As a result, during the revolution turning motion, the width of the sealed space decreases according to the spiral shape of the wall body, and the height of the sealed space, that is, the distance between the opposing surfaces between the end plates increases. Therefore, at least a part of the first region in which the volume change of the sealed space is moderately or substantially constant is set depending on the positions and shapes of the first wall body inclined portion and the first end plate inclined portion. As the fluid sucked from the outer peripheral side moves toward the inner peripheral side, the pressure in the sealed space is maintained substantially constant in the first region.

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

  The slopes of the first wall slope part and the first end plate slope part are not limited to smoothly connected slopes, but small steps are connected in a staircase pattern, and the first wall slope part is entirely If it sees, what is inclined continuously is included. A 1st wall body inclination part and a 1st end plate inclination part may be provided in the both sides of a 1st scroll member and a 2nd scroll member, and may be provided in any one. 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, A shape combined with a stepped shape may be used.

  In the above invention, at least one of the first wall body and the second wall body has a second wall body inclined portion in which the height of the wall body continuously decreases from the outer peripheral side in the spiral direction toward the inner peripheral side. And at least one of the first wall body and the second wall body has a tooth bottom surface facing a tooth tip of the first wall body inclined portion inclined according to the inclination of the second wall body inclined portion. A second end plate inclined portion is provided, and at least a part of each of the second region and the third region is set according to the position and shape of the second wall body inclined portion and the second end plate inclined portion. Also good.

  According to this configuration, the height of the wall body in the second wall body inclined portion decreases from the outer peripheral side toward the inner peripheral side, and the second end plate inclined portion faces the tooth tip of the second wall body inclined portion. The tooth bottom surface to be inclined is inclined according to the inclination of the second wall inclined portion. Therefore, at least a part of each of the second region and the third region in which the volume of the sealed space decreases is set according to the positions and shapes 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 reduction of the width of the sealed space according to the spiral shape of the wall body, but also the height of the sealed space, that is, the end as it goes to the inner peripheral side. Further compression is achieved by reducing the distance between the opposing surfaces of the plates. As a result, three-dimensional compression is possible, and downsizing can be realized.

  According to the present invention, it is possible to prevent the sealed space from becoming a pressure higher than a predetermined pressure before the fluid supply unit, so that the intermediate pressure refrigerant can be reliably introduced during the compression process or the expansion process, An increase in pressure in the sealed space can be suppressed. When the scroll fluid machine is applied as a compressor, the compressor efficiency can be improved.

It is a block diagram which shows the refrigerating cycle which concerns on one Embodiment of this invention. It is a fragmentary longitudinal cross-section which shows the principal part of the scroll compressor which concerns on one Embodiment of this invention. It is a longitudinal section showing a fixed scroll of a scroll compressor concerning one embodiment of the present invention. 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 end plate of the wall body of the fixed scroll which concern on one Embodiment of this invention. It is the side view which expanded and showed the wall and end plate of the fixed scroll which concern on one Embodiment of this invention in the spiral direction. It is a longitudinal cross-sectional view which shows the turning scroll of the scroll compressor which concerns on one Embodiment of this invention, and is the VII-VII arrow line 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 end plate of the wall body of the turning scroll which concern on one Embodiment of this invention. It is the side view which expanded and showed the wall body and end plate of the turning scroll which concern on one Embodiment of this invention in the spiral direction. It is a side view showing a chip seal gap of a scroll compressor concerning one embodiment of the present invention, (a) shows a state where a chip seal gap is relatively small, and (b) shows a state where a chip seal is relatively large Indicates. 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. It is a top view which shows the fixed scroll which concerns on one Embodiment of this invention.

Embodiments according to the present invention will be described below with reference to the drawings.
As shown in FIG. 1, the refrigeration cycle 10 has a scroll compressor 1 that compresses refrigerant (fluid), a condenser 2 that radiates heat of the compressed refrigerant to the outside, and decompresses the refrigerant that has flowed out of the condenser 2. A first expansion valve 3 provided on the high-pressure side, an economizer (gas-liquid separator) 4 that separates the decompressed refrigerant into liquid refrigerant and gas refrigerant, and a second provided on the low-pressure side that further depressurizes the liquid refrigerant. An expansion valve 5, an evaporator 6 that absorbs heat by 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 are provided.

  The scroll compressor 1 is a hermetic compressor, and as illustrated in FIG. 2, a scroll 11 that compresses a housing 11 having a sealed space therein and a refrigerant that is disposed in the housing 11 and is taken into the sealed space. The main elements are a mechanism 12, a rotating shaft that transmits a rotational force to the scroll compression mechanism 12, and an electric motor that orbits the revolving scroll 19 of the scroll compression mechanism 12 via the rotating shaft.

  The housing 11 is sealed at the bottom by a lower cover, and is provided with a cylindrical intermediate cover 13 that is long in the vertical direction at the top of the lower cover. 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 hermetically sealed. A discharge of compressed high-pressure gas is discharged between the discharge cover 14 and the upper cover 15. A 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 fixedly installed on the housing 11, a slidably supported, and a revolving scroll 19 that forms a compression chamber 20 by being engaged with the fixed scroll 18.

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

  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 through the suction port 21 on the outer peripheral side opened to the inside of the housing 11 and compresses the refrigerant gas. To 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 sent out of the compressor via a discharge pipe 24 communicating with the discharge chamber 16.

  Further, the discharge cover 14 is provided with an injection pipe 25 through which the intermediate pressure refrigerant is introduced from the outside into the compression chamber 20 of the scroll compression mechanism 12 through the upper cover 15. A refrigerant is supplied to the compression chamber 20 via the injection pipe 25 and the injection port (fluid supply part) 26.

  The reed valve 27 is a thin plate member and is provided at the outlet of the discharge port 22 to open and close the discharge port 22. The reed valve 27 regulates the flow of the 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 includes a substantially disc-shaped end plate (first end plate) 18 a and a spiral wall body (first plate) standing on one side surface of the end plate 18 a. 1 wall) 18b. As shown in FIG. 2, the orbiting scroll 19 includes a substantially disc-shaped end plate (second end plate) 19 a and a spiral wall body (first plate) erected on one side surface of the end plate 19 a. 2 walls) 19b. The spiral shape of each wall 18b, 19b is defined using, for example, an involute curve or an Archimedean curve.

  The fixed scroll 18 and the orbiting scroll 19 are meshed with their centers O1 and O2 separated by the orbiting radius ρ and the phases of the wall bodies 18b and 19b shifted by 180 °, and the tooth tips of the wall bodies 18b and 19b of the scrolls 18 and 19 are engaged. And the tooth bottom are assembled so as to have a slight height clearance (chip clearance) at room temperature. Accordingly, a plurality of pairs of compression chambers 20 formed between the scrolls 18 and 19 and 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 orbiting scroll 19 revolves around the fixed scroll 18 by a rotation prevention mechanism such as an Oldham ring (not shown).

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

  As shown in FIGS. 3, 5 and 6, the wall body 18 b of the fixed scroll 18 has a wall body flat part 18 b 1, a second wall body inclined part 18 b 2, and a wall body flat part from the outer peripheral side toward 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. As shown in FIGS. 3, 4, and 6, an end plate flat portion 18 a 1, a second end plate inclined portion 18 a 2, and an end plate are formed on the tooth bottom surface of the fixed scroll 18 from the outer peripheral side toward 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 19 b of the orbiting scroll 19 has a wall body flat part 19 b 1, a second wall body inclined part 19 b 2, and a wall body flat part from the outer peripheral side toward 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 end plate flat portion 19 a 1, the second end plate inclined portion 19 a 2, and the end plate are formed on the tooth bottom surface of the orbiting scroll 19 from the outer peripheral side toward 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 wall flat portions 19b1, 19b3, 19b5, 19b7 provided on the wall 19b of the orbiting scroll 19 have a constant height from the outer peripheral side toward the inner peripheral side. That is, the dimension in the axial direction passing through the center O2 (see FIG. 2) of the orbiting 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, wall body flat portions 19b1 and 19b7 having a constant height are provided on the outermost and innermost sides of the wall body 19b of the orbiting scroll 19, respectively. . As shown in FIG. 8, these wall body flat portions 19b1 and 19b7 cover a region of 180 ° (for example, 180 ° to 360 °, preferably 210 ° or less) around the center O2 (see FIG. 2) of the orbiting scroll 19. Is provided.

  Similarly, the bottom of the end plate 19a of the orbiting scroll 19 is provided with end plate flat portions 19a1 and 19a7 having a constant height. The end plate flat portions 19a1 and 19a7 are also provided over a region of 180 ° (for example, 180 ° to 360 °, preferably 210 ° or less) around the center O2 of the orbiting scroll 19.

  As shown in FIG. 4, the fixed scroll 18 is also provided with wall body flat portions 18 b 1 and 18 b 7 and end plate flat portions 18 a 1 and 18 a 7, similarly to the orbiting scroll 19. The wall flat portions 18b1 and 18b7 and the end plate flat portions 18a1 and 18a7 are also provided over a region of 180 ° (for example, 180 ° to 360 °, preferably 210 ° or less) around the center O1 of the fixed scroll 18. .

  As shown in FIG. 10, the height of the first wall inclined portion 19b4 provided on the wall 19b of the orbiting scroll 19 increases continuously from the outer peripheral side toward the inner peripheral side. As shown in FIG. 6, the tooth bottom surface on the end plate 18a of the fixed scroll 18 where the tooth tips of the first wall inclined portion 19b4 face each other is inclined according to the inclination of the first wall inclined portion 19b4. One end plate inclined portion 18a4 is provided. Similarly, as shown in FIG. 6, the first wall inclined portion 18b4 provided on the wall 18b of the fixed scroll 18 also increases continuously from the outer peripheral side toward the inner peripheral side, as shown in FIG. Further, on the tooth bottom surface of the end plate 19a of the orbiting scroll 19 facing the tooth tip of the first wall inclined portion 18b4, a first end plate inclined portion inclined according to the inclination of the first wall inclined portion 18b4. 19a4 is provided. The lengths in the spiral direction of the first wall inclined portions 18b4 and 19b4 and the first end plate inclined portions 18a4 and 19a4 are set to be equivalent to 20 ° or more, preferably 180 ° or more around the centers O1 and O2. .

  As a result, during the revolving orbiting motion of the orbiting scroll 19, the width of the compression chamber 20 decreases according to the spiral shape of the wall bodies 18b and 19b, and the height of the compression chamber 20, that is, the facing between the end plates 18a and 19a. The distance between surfaces increases. Therefore, the volume change of the compression chamber 20 is moderate or slow depending on the position and shape of the first wall body inclined portions 18b4 and 19b4 and the first end plate inclined portions 18a4 and 19a4 in the spiral direction (for example, the inclination angle and the length in the spiral direction). At least a part of the first region that is substantially constant is set. As the fluid sucked in from the suction port 21 on the outer peripheral side moves 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 inclined portion 18b4, 19b4 or first end plate inclined portion 18a4, 19a4 over the spiral direction, or may include a plurality of first walls. The body inclined portions 18b4 and 19b4 or the first end plate inclined portions 18a4 and 19a4 may be set in series. When the plurality of first wall body inclined portions 18b4, 19b4 or the first end plate inclined portions 18a4, 19a4 are arranged in series, the respective inclination angles are different, or the wall body flat portion or the end plate flat portion is interposed therebetween. It is realized by providing.

  The end plate 18 a of the fixed scroll 18 is provided with an injection port 26 that supplies a refrigerant having a pressure higher than the fluid pressure in the compression chamber 20 into the compression chamber 20. When the orbiting scroll 19 revolves and the tooth tip of the wall 19b of the orbiting scroll 19 moves onto the injection port 26 and overlaps, the communication between the compression chamber 20 and the injection port 26 is closed. On the other hand, when the tooth tip of the wall 19b of the orbiting scroll 19 moves from 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, 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 level or more in a process in which the pressure change in the compression chamber 20 is moderate or substantially constant. In the first region, an intermediate pressure refrigerant injection step is performed.

  The height of the second wall body inclined portions 19b2 and 19b6 provided on the wall body 19b of the orbiting scroll 19 decreases continuously from the outer peripheral side toward the inner peripheral side. A second end plate that inclines according to the inclination of the second wall body inclined portions 19b2 and 19b6 on the tooth bottom surface of the end plate 18a of the fixed scroll 18 where the tooth tips of the second wall body inclined portions 19b2 and 19b6 face each other. Inclined portions 18a2 and 18a6 are provided. Similarly, the second wall body inclined portions 18b2 and 18b6 provided on the wall body 18b of the fixed scroll 18 also continuously decrease from the outer peripheral side toward the inner peripheral side, and the second wall body inclined portions 18b2 and 18b6. Second end plate inclined portions 19a2 and 19a6 that are inclined in accordance with the inclination of the second wall body inclined portions 18b2 and 18b6 are provided on the tooth bottom surface of the end plate 19a of the orbiting scroll 19 that faces the tooth tips. .

  As a result, during the revolving orbiting motion of the orbiting scroll 19, the width of the compression chamber 20 decreases according to the spiral shape of the wall bodies 18b and 19b, and the height of the compression chamber 20, that is, the facing between the end plates 18a and 19a. The distance between surfaces decreases. Therefore, the second wall body inclined portions 18b2, 18b6, 19b2, 19b6 and the second end plate inclined portions 18a2, 18a6, 19a2, 19a6 are compressed depending on the positions and shapes (for example, the inclination angle and the length in the spiral direction) of the second end plate inclined portions 18a2, 18a6, 19a2, 19a6. At least a part of each of the second region and the third region in which the volume of the chamber 20 decreases is set. As the refrigerant sucked from the suction port 21 on the outer peripheral side goes toward the inner peripheral side, the refrigerant 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, but also the compression chamber 20 Further compression is caused by a decrease in height, that is, a distance between the opposing surfaces between the end plates 18a and 19a. As a result, three-dimensional compression is possible, and downsizing can be realized.

  The second region in which the volume of the compression chamber 20 decreases is set in front of the first region in the movement direction of the compression chamber 20 associated with the revolving orbiting motion of the orbiting scroll 19, and the third region is in the movement direction of the compression chamber 20. It is set after the first area. The second region is a region from when the wall bodies 18b and 19b are engaged with each other on the outer peripheral side to form the compression chamber 20 and shut down until the first region starts. The third region is a region from the end of the first region to the end of 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 in front of the first region, as the refrigerant moves toward the inner peripheral side, Pressure increases. The refrigerant whose pressure has increased is directed toward the inner periphery in the first region, 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, in the third region after the first region, the refrigerant moves toward the inner peripheral side as the compression chamber 20 moves toward the inner peripheral side. The pressure inside rises again. A low-stage compression process is performed in the second region, and a high-stage compression process is performed in the third region. The gradual volume change 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.

  As described above, a two-stage compression refrigeration cycle is realized in which the refrigerant is introduced into the middle of the compression process of the scroll compression mechanism 12 from the economizer 4 through the injection flow path 7 and the injection port 26. Further, a first region in which the volume change of the compression chamber 20 is moderately or substantially constant is provided between the second region and the third region where the volume of the compression chamber 20 decreases, 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 inclined portions 18b4 and 19b4, the first end plate inclined portions 18a4 and 19a4, the second wall inclined portions 18b2, 18b6, 19b2 and 19b6, and the second end plate inclined portions 18a2 and 18a6 referred to in this embodiment. , 19a2 and 19a6 are not limited to smoothly connected slopes, but small steps that inevitably occur during fabrication by machining or additive manufacturing (AM) are connected in a staircase pattern. If the inclined portion is viewed as a whole, it may be continuously inclined. However, large steps such as so-called stepped scrolls are not included.

  The first wall inclined portions 18b4, 19b4, the first end plate inclined portions 18a4, 19a4, the second wall inclined portions 18b2, 18b6, 19b2, 19b6 and the second end plate inclined portions 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 and 19b8 of the second wall inclined portions 18b2 and 19b2 arranged on the outer peripheral side with respect to the first wall inclined portions 18b4 and 19b4 are as follows. The tooth tip heights at the inner peripheral side end portions 18b9 and 19b9 of the first wall body inclined portions 18b4 and 19b4 may be the same. As a result, measurement can be performed at one end 18b8, 19b8 and the other end 18b9, 19b9 with the first wall inclined portions 18b4, 19b4 and the second wall inclined portions 18b2, 19b2 interposed therebetween. The dimension measurement of the fixed scroll 18 or the orbiting scroll 19 can be suitably performed.

  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 with respect to the first end plate inclined portions 18a4 and 19a4. , 19a8 may be the same as the bottom surface height at the inner peripheral side end portions 18a9, 19a9 of the first end plate inclined portions 18a4, 19a4. Thereby, with the first end plate inclined portions 18a4 and 19a4 and the second end plate inclined portions 18a2 and 19a2 interposed therebetween, measurement is performed at one end portions 18a8 and 19a8 and the other end portions 18a9 and 19a9. The dimensions of the fixed scroll 18 or the orbiting scroll 19 can be suitably measured.

  A tip seal is provided at the tooth tip of the wall 18 b of the fixed scroll 18. The tip seal is made of resin and seals the fluid by contacting the tooth bottom of the end plate 19a of the orbiting scroll 19 facing the tip seal. The tip seal is accommodated in a tip seal groove 18d formed in the tooth tip of the wall 18b over the circumferential direction. Similarly, a tip seal groove 19d is formed on the tooth tip of the wall 19b of the orbiting scroll 19, and a tip seal is provided in the tip seal groove 19d.

  When the scrolls 18 and 19 perform a revolving orbiting motion relatively, the positions of the tooth tip and the tooth bottom are relatively shifted by the turning diameter (turning radius ρ × 2). Due to the positional deviation 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 to the tooth bottom side of the end plate 19a by the compressed fluid, so that it can be followed and sealed.

  As shown in FIGS. 2 to 5 and 13, the end plate 18 a of the fixed scroll 18 is provided with a first bypass port 31 and a second bypass port 32.

  The first bypass port 31 is provided in front of the injection port 26 in the moving direction of the compression chamber 20 associated with the revolution turning motion, and the first bypass port 31 is a refrigerant that is compressed in the compression chamber 20 and has a pressure higher than a predetermined pressure. Is discharged outside the compression chamber 20. The first bypass port 31 is provided in the second region. Thereby, in the second region before the injection port 26, the compression chamber 20 can be prevented from becoming a pressure higher than a predetermined pressure, for example, a pressure higher than the high-pressure refrigerant supplied via the injection port 26, In the first region, a predetermined amount of refrigerant can be supplied into the compression chamber 20 via the injection port 26.

  The outlet of the first bypass port 31 is formed to open in the same space as the outlet of the injection port 26. As a result, the refrigerant discharged from the first bypass port 31 is guided to the same space as the outlet of the injection port 26 and is supplied again into the compression chamber 20 together with the refrigerant supplied from the injection port 26.

  A second bypass port 32 is provided behind the injection port 26 in the direction of movement of the compression chamber 20 associated with the revolution turning motion, and the second bypass port 32 is a refrigerant compressed in the compression chamber 20 and having a pressure higher than a predetermined level. It is discharged outside the compression chamber 20. As a result, in the third region after the injection port 26, the compression chamber 20 prevents a pressure higher than a predetermined level, for example, a refrigerant discharged through the discharge port 22 from becoming a pressure higher than a predetermined level. it can.

  The outlet of the second bypass port 32 is formed to open in the same space as the discharge port 22 provided on the most downstream side of the compression chamber 20. As a result, the refrigerant discharged from the second bypass port 32 is guided to the same space as the discharge port 22 provided on the most downstream side of the compression chamber 20, and is discharged to the outside together with the refrigerant discharged from the discharge port 22. .

The scroll compressor 1 described above operates as follows.
The orbiting scroll 19 revolves around the fixed scroll 18 by a driving 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, after the wall bodies 18b and 19b are engaged with each other on the outer peripheral side to form the compression chamber 20 and shut down, the refrigerant in the compression chamber 20 is compressed as it moves from the outer peripheral side to the inner peripheral side in the second region. Then, as shown in FIG. 12, the pressure in the compression chamber 20 increases. The compressed refrigerant moves to the first region, and in the first region, the refrigerant moves toward the inner peripheral side. Then, an 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 moderate or substantially constant, and the fluid is supplied to the compression chamber while maintaining the pressure difference with the refrigerant supplied from the economizer 4 at a predetermined level or more. 20 can be supplied.

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

As mentioned above, according to the scroll compressor 1 of this embodiment, there exist the following effects.
Since the first bypass port 31 is provided in front of the injection port 26 in the moving direction of the compression chamber 20 associated with the revolution swivel motion, the compression chamber 20 in the second region before the injection port 26 For example, when it is possible to prevent a pressure higher than that of the high-pressure refrigerant supplied through the injection port 26, the first region has a predetermined amount through the injection port 26. The refrigerant can be supplied into the compression chamber 20.

  When the outlet of the first bypass port 31 is formed in the same space as the outlet of the injection port 26, the refrigerant discharged from the first bypass port 31 is introduced into the same space as the outlet of the injection port 26. It is burned. As a result, the refrigerant is supplied again into the compression chamber 20 together with the refrigerant supplied from the injection port 26.

  Since the second bypass port 32 is provided behind the injection port 26 in the movement direction of the compression chamber 20 associated with the revolving and turning motion, the second bypass port 32 is compressed in the compression chamber 20 and has a pressure higher than a predetermined pressure. Is discharged to the outside of the compression chamber 20. As a result, in the third region after the injection port 26, the compression chamber 20 prevents a pressure higher than a predetermined level, for example, a refrigerant discharged through the discharge port 22 from becoming a pressure higher than a predetermined level. it can.

  When the outlet of the second bypass port 32 is formed to open in the same space as the discharge port 22 provided on the most downstream side of the compression chamber 20, the refrigerant discharged from the second bypass port 32 is compressed into the compression chamber 20. Is guided to the same space as the discharge port 22 provided on the most downstream side. As a result, the refrigerant is discharged to the outside together with the refrigerant discharged from the discharge port 22.

  Since the slope between the opposing surfaces of the end plates 18a, 19a is continuously reduced from the outer peripheral side to the inner peripheral side of the wall bodies 18b, 19b, three-dimensional compression is possible, and miniaturization is achieved. Can be realized.

  Since the distance between the opposing surfaces between the end plates 18a and 19a is continuously increased from the outer peripheral side to the inner peripheral side of the wall bodies 18b and 19b, the sealing of the compression chamber 20 is started. A first region in which the volume change of the compression chamber 20 is gradual or substantially constant is set. Since the injection port 26 is provided in the first region, the refrigerant is supplied to the compression chamber while maintaining the pressure difference with the supplied refrigerant at a predetermined level or higher while the pressure change in the compression chamber 20 is moderate or substantially constant. 20 can be reliably supplied.

  Since the slope between the opposing surfaces of the end plates 18a, 19a is continuously reduced from the outer peripheral side to the inner peripheral side of the wall bodies 18b, 19b, three-dimensional compression is possible, and miniaturization is achieved. Can be realized.

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

  Since the tip seal 28 is provided at the tooth tips 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.

  The walls 18b and 19b and / or the end plates 18a and 19a are coated. As a result, it is possible to compensate for the machining variation of the inclined portion where it is difficult to obtain machining accuracy with the film thickness of the coating, and to further suppress fluid leakage.

  The wall body flat portions 18b1, 18b7, 19b1, 19b7 and the end plate flat portions 18a1, 18a7, 19a1, 19a7 are provided on the outermost and innermost peripheral portions of the wall bodies 18b, 19b and the end plates 18a, 19a. Thereby, when the tooth tip of the wall body is inclined, it is difficult to set measurement points and it is difficult to increase measurement accuracy, and shape measurement can be performed with high accuracy. In addition, 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 region of 180 °, the flat portions on both sides sandwiching the centers 01, 02 of the scrolls 18, 19 Measurements can be made. Thereby, the shape dimension of the fixed scroll 18 or the turning scroll 19 can be performed suitably.
Further, if the range of the flat portion greatly exceeds 180 °, the region of the inclined portion is reduced and the inclination φ of the inclined portion is increased. When the inclination φ increases, the amount of change in the tip clearance T due to the turning diameter during the revolving turning motion increases, and there is a risk that fluid leakage will increase. Therefore, the wall body flat portions 18b1, 18b7, 19b1, 19b7 and the end plate flat portions 18a1, 18a7, 19a1, 19a7 are defined as 180 ° regions. However, this 180 ° is not strict, and an angle slightly exceeding 180 ° (for example, about 30 °) is allowed within a range where 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. Thereby, the tip clearance T resulting from 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 portions 18b4, 19b4, the first end plate inclined portions 18a4, 19a4, the second wall body inclined portions 18b2, 18b6, 19b2, 19b6, and the second end plate inclined portions 18a2, 18a6, 19a2 are used. , 19a6 are provided on both scrolls 18, 19, but may be provided on either one of them.
Specifically, the first wall body inclined portion 19b4 and the second wall body inclined portions 19b2 and 19b6 are provided on one wall body (for example, the wall body 19b of the orbiting scroll 19), and the other end plate (for example, the fixed scroll 18 of the fixed scroll 18). When the first end plate inclined portion 19a4 and the second end plate inclined portions 19a2 and 19a6 are provided on the end plate 18a), the other wall body 18b and the one end plate 19a are flat.
The shape combined with the conventional stepped shape, that is, the end plate 18a4 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 orbiting scroll 19 is provided. You may combine with the shape in which the step part was provided in 19a.

  In the present embodiment, the wall flat portions 18b1, 18b7, 19b1, 19b7 and the end plate flat portions 18a1, 18a7, 19a1, 19a7 are provided, but the inner peripheral side and / or the outer peripheral side flat portions are omitted. You may make it provide the 2nd wall body inclination part 18b2, 19b2 extending in the whole wall body 18b, 19b.

  In the present embodiment, the case where the first area, the second area, and the third area are set has been described, but the present invention is not limited to this example. In the case of a compression mechanism in which an injection port (fluid supply unit) is installed, similarly, a first bypass port (first fluid discharge unit) or a second bypass port (second fluid discharge unit) is provided before and after the injection port. be able to. Further, the setting of the first region is not limited to the example in which the first wall body inclined portion, the first end plate inclined portion, the second wall body inclined portion, and the second end plate inclined portion are formed. As described above, the first region where the volume change of the compression chamber is moderately or substantially constant may be set by the stepped portion.

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

1: Scroll compressor 2: Condenser 3: 1st expansion valve 4: Economizer 5: 2nd expansion valve 6: Evaporator 7: Injection flow path 10: Refrigeration cycle 11: Housing 12: Scroll compression mechanism 13: Intermediate cover 14 : Discharge cover 15: Upper cover 15a: Discharge port 16: Discharge chamber 18: Fixed scroll 18a: End plate 18a1: End plate flat part 18a2: Second end plate inclined part 18a3: End plate flat part 18a4: First end plate inclined Part 18a5: end plate flat part 18a6: second end plate inclined part 18a7: end plate flat part 18a8: outer peripheral side end part 18a9: inner peripheral side end part 18b: wall body 18b1: wall body flat part 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 end 18b9: Inner peripheral end 18d: Chip seal groove 19: Orbiting scroll 19a: End plate 19a1: End plate flat portion 19a2: Second end plate inclined portion 19a3: End plate flat portion 19a4: First 1 end plate inclined part 19a5: end plate flat part 19a6: second end plate inclined part 19a7: end plate flat part 19a8: outer peripheral side end part 19a9: inner peripheral side end part 19b: wall body 19b1: wall body flat part 19b2: 2nd wall body inclined part 19b3: Wall body flat part 19b4: 1st wall body inclined part 19b5: Wall body flat part 19b6: 2nd wall body inclined part 19b7: Wall body flat part 19b8: Outer peripheral side edge part 19b9: Inner circumference Side end 20: Compression chamber 21: Suction port 22: Discharge port 23: Discharge port 24: Discharge tube 25: Injection tube 26: Injection port 27: Reed valve 28: Tip seal 31 : First bypass port 32: Second bypass port

Claims (8)

A first scroll member provided with a spiral first wall on the first end plate;
A spiral second wall is provided on a second end plate disposed to face the first end plate, and the second wall engages with the first wall to form a sealed space. A second scroll member that relatively revolves, and
With
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 sealed space into the sealed space.
The first end plate or the second end plate is a fluid that is compressed in the sealed space and has a pressure equal to or higher than a predetermined level before the fluid supply unit in the moving direction of the sealed space accompanying the revolving and turning motion. A scroll fluid machine is provided, wherein a first fluid discharge portion is provided for discharging the gas to the outside of the sealed space.   2. The scroll fluid machine according to claim 1, wherein the outlet of the first fluid discharge unit is formed to open in the same space as the outlet of the fluid supply unit.   The first end plate or the second end plate is a fluid that is compressed in the sealed space and has a pressure equal to or higher than a predetermined value after the fluid supply unit in the moving direction of the sealed space accompanying the revolving and turning motion. The scroll fluid machine according to claim 1, further comprising a second fluid discharge unit that discharges the fluid to the outside of the sealed space.   4. The scroll fluid machine according to claim 3, wherein an outlet of the second fluid discharge unit is formed to open in the same space as a discharge port provided on the most downstream side of the sealed space. After the sealing of the sealed space is started, a first region where the volume change of the sealed space becomes gentle or substantially constant, and a second region where the volume of the sealed space decreases before the first region are set. And
The fluid supply section is provided in the first region;
The scroll fluid machine according to any one of claims 1 to 4, wherein the first fluid discharge portion is provided in the second region. A third region in which the volume of the sealed space decreases after the first region is set,
The scroll fluid machine according to claim 5, wherein the second fluid discharge portion is provided in the third region. 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 in the spiral direction toward the inner peripheral side,
At least one of the first end plate and the second end plate is a first end plate in which a tooth bottom surface facing a tooth tip of the first wall inclined portion is inclined according to the inclination of the first wall inclined portion. Has an inclined part,
The scroll fluid machine according to claim 5 or 6, wherein at least a part of the first region is set according to a position and a shape of the first wall body inclined portion and the first end plate inclined portion. . At least one of the first wall body and the second wall body has a second wall body inclined portion in which the height of the wall body continuously decreases from the outer peripheral side in the spiral direction toward the inner peripheral side,
At least one of the first wall body and the second wall body has a second end plate in which a tooth bottom surface facing a tooth tip of the first wall body inclined portion is inclined according to the inclination of the second wall body inclined portion. Has an inclined part,
The at least part of each of said 2nd area | region and said 3rd area | region is set by the position and shape of a said 2nd wall body inclination part and a said 2nd end plate inclination part from Claim 5 characterized by the above-mentioned. The scroll fluid machine according to any one of 7.

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