Scroll compressor

Abstract

A scroll compressor includes a fixed scroll and an orbiting scroll. The fixed scroll includes a fixed base and a fixed spiral wrap, and the orbiting scroll includes an orbiting base and an orbiting spiral wrap where the fixed spiral wrap and the orbiting spiral wrap are fitted together creating a compression chamber for compressing refrigerant that is supplied to the scroll compressor. The compression chamber has a first compression chamber and a second compression chamber. At least two injection ports are provided in the fixed base for injecting refrigerant, wherein the first injection port and the second injection port inject refrigerant to the first compression chamber and the second compression chamber respectively at the same time when a crank angle of the orbiting scroll is in a specified range and the first injection port and second injection port are neighboring each other in radial direction.

Description

[Title of the Invention]SCROLL COMPRESSOR[Technical Field]

[0001] The present disclosure relates to a scroll compressor having injection ports.[Background Art]

[0002] A conventional scroll compressor includes a fixed spiral wrap of a fixed scroll and an orbiting spiral wrap of an orbiting scroll engaging together to form a compression chamber such that when refrigerant is supplied to the compression chamber, it is compressed for further usage such as the air-conditioning system. The scroll compressor disclosed in Patent Literature 1 provides a plurality of compression chambers formed between the first lap and the second lap. The compression chambers include at least a first compression chamber and a second compression chamber that has a volume smaller than the first compression chamber, and a first base plate is provided with a first injection port for injection of refrigerant into the first compression chamber and a second injection port for injection of refrigerant into the second compression chamber. The injection flow rate of the second injection port is higher than the injection flow rate of the first injection port. The first injection port and the second injection port are provided at positions that do not allow the injected refrigerant to flow into a lower pressure space.

[0003] While in a certain period one of the injection ports communicates with a compression chamber, the other of the injection ports is completely closed by the second wrap of the orbiting scroll from the compression chamber. As a result, the two different compression chambers are prevented from communicating with each other via the injection ports.[Citation List][Patent Literature]

[0004] Patent Literature 1: United States Patent No. 10227984[Summary of Invention][Technical Problem]

[0005] According to the invention described in Patent Literature 1, having the first injection port inject refrigerant into the first compression chamber and the second injection port inject refrigerantinto the second compression chamber, without communicating with each other via injection ports, improves efficiency of the scroll compressor.

[0006] The present invention has been made to overcome the above problem, and has an objective to provide a scroll compressor that increases the capacity allowing more refrigerant to be operated in a given time frame.[Solution to Problem]

[0007] A scroll compressor according to the present invention includes a fixed scroll including a fixed base and a fixed spiral wrap extending from the fixed base, an orbiting scroll including an orbiting base and an orbiting spiral wrap extending from the orbiting base, the fixed spiral wrap and the orbiting spiral wrap being fitted together creating a compression chamber. The orbiting scroll revolving relatively to the fixed scroll to compress refrigerant that being supplied to the compression chamber. The compression chamber has a first compression chamber and a second compression chamber. The scroll compressor further includes at least two injection ports being provided on the fixed base for injecting an additional refrigerant to the compression chamber where injection ports include a first injection port and a second injection port. The first injection port and second injection port inject refrigerant to the first compression chamber and the second compression chamber respectively at the same time when a crank angle of the orbiting scroll is in a specified range, and the first injection port and second injection port are neighbouring each other in radial direction. A scroll compressor with these characteristics has better efficiency and increases the capacity allowing more refrigerant to be operated in a given time frame. The specified range of the crank angle of the orbiting scroll, where the first injection port and the second injection port inject refrigerant to the first compression chamber and the second compression chamber respectively at the same time, starts at a first stage of the compression where a refrigerant pressure is more than a pressure inside the compression chamber. As a result, the injection capacity of refrigerant is increased resulting in better efficiency of the scroll compressor. The specified range of the crank angle of the orbiting scroll in this invention is 10 degrees to 30 degrees and / or -170 degrees to -160 degrees so that the scroll compressors of this invention have the highest efficiency. Injection ports of the scroll compressor are provided in between an outermost fixed spiral wrap and an inwardly adjacent fixed spiral wrap, in a range of a quarter of a distance from the inward face of the outermost fixed spiral wrap to a quarter of a distance from the outward face of the inwardly adjacent fixed spiral wrap. This is an appropriate position of the injection ports in order for the scroll compressor according to the present invention to have better efficiency. The firstinjection port is positioned in a range of a quarter of the distance between the outermost fixed spiral wrap and the inwardly adjacent fixed spiral wrap, which is from an inward face of the outermost fixed spiral wrap to less than a half of the distance between the outermost fixed spiral wrap and the inwardly adjacent fixed spiral wrap, the second injection port is positioned in a range of a quarter of the distance between the outermost fixed spiral wrap and the inwardly adjacent fixed spiral wrap, which is from an outward face of the inwardly adjacent fixed spiral wrap to less than a half of the distance between the outermost fixed spiral wrap and the inwardly adjacent fixed spiral wrap. For the full potential of the scroll compressor according to the present invention, the positions of the first injection port and the second injection port are as described. Injection ports continuously inject refrigerant to the compression chamber throughout the orbiting scroll revolving motion where the range of the orbiting scroll revolving motion is not more than 200 degrees. This results in increasing the capacity of the compressed refrigerant. Furthermore, the injection ports include a round or elongate shape such that the scroll compressor of the present invention expands its varieties for use in various applications. For the scroll compressor according to the present invention to be operated to its full potential, the scroll compressor of the invention is an asymmetric oval scroll compressor.[Advantageous Effects of Invention]

[0008] In the scroll compressor according to the present invention, having multiple injection ports inject refrigerant to the first compression chamber and the second compression chamber at the same time for a certain period increases the capacity of the compressed refrigerant, reducing the injection period while maintaining or improving the injection capacity and decreasing the compressed refrigerant temperature. The scroll compressor according to the present invention has better efficiency and coefficient of performance.[Brief Description of Drawings]

[0009] Fig. l is a schematic cross-sectional view of a scroll compressor.Fig. 2 is a schematic cross-sectional view of a compression mechanism portion of the scroll compressor.Fig. 3 is a schematic view of a fixed scroll and an orbiting scroll of the scroll compressor.Fig. 4 shows an eccentric rotary motion of the orbiting scroll revolving relatively to the fixed scroll of the scroll compressor in full cycle.Fig. 5 shows an eccentric rotary motion of the orbiting scroll revolving relatively to the fixed scroll of the scroll compressor in a crank angle range of 10 degrees to 30 degrees.Fig. 6 shows an eccentric rotary motion of the orbiting scroll revolving relatively to the fixed scroll of the scroll compressor in a crank angle range of -180 degrees to -150 degrees.Fig. 7 is a graph showing the injection range of injection ports at each crank angle of the eccentric rotary motion of the orbiting scroll revolving relatively to the fixed scroll of the scroll compressor. Fig. 8 shows a fixed scroll and an orbiting scroll of the scroll compressor with multiple injection ports at a crank angle of 20 degrees.Fig. 9 shows a fixed scroll and an orbiting scroll of the scroll compressor with multiple injection ports at a crank angle of -160 degrees.[Description of Embodiments]

[0010] The present disclosure throughout the entire description refers to drawings and embodiments for understanding the invention clearly in such a way that the invention is not limited only to the disclosed drawings and embodiments, and the scope of the invention should be understood according to what is defined by the claims of the present invention.(Embodiment 1)

[0011] Figs. 1 and 2 show a schematic cross-sectional view of a scroll compressor 1 and a compression mechanism portion 10, where the scroll compressor 1 has a function of suctioning the refrigerant, compressing the refrigerant into a high-temperature and high-pressure state, and discharging the compressed refrigerant. The scroll compressor 1 includes the compression mechanism portion 10, a drive mechanism portion 11, and other components, which all are accommodated in a shell 12 being an outer casing. In the shell 12, the drive mechanism portion 11 is located on the lower part of the shell 12 and the compression mechanism portion 10 is located on the upper part of the shell 12. In this embodiment, the drive mechanism portion 11 is similar to those commercial scroll compressors.

[0012] A suction pipe 13 is connected to the shell 12 where the refrigerant is suctioned into the scroll compressor 1 at the top of the scroll compressor 1, and the refrigerant is discharged out of the scroll compressor 1 through a discharge pipe 14 that is also connected to the shell 12 at the side of the scroll compressor 1. In order to perform, the compression mechanism portion 10 compresses the refrigerant suctioned through the suction pipe 13 and discharges the compressed refrigerant through the discharge pipe 14. The drive mechanism portion 11 has a function of driving the compression mechanism portion 10 and includes a rotational shaft 15 operated together with lubricant stored in a reservoir 16 at the bottom of the scroll compressor 1 to drive thecompression mechanism portion 10, so the refrigerant is compressed in the compression mechanism portion 10.

[0013] The compression mechanism portion 10 includes a fixed scroll 2 and an orbiting scroll 3 where the orbiting scroll 3 is located on the lower side and the fixed scroll 2 is located on the upper side. The fixed scroll 2 includes a fixed base 2a and a fixed spiral wrap 2b extending from one side of the fixed base 2a. The orbiting scroll 3 includes an orbiting base 3 a and an orbiting spiral wrap 3b extending from one side of the orbiting base 3 a. The fixed scroll 2 and the orbiting scroll 3 are fitted to the inside of the shell 12 with the fixed spiral wrap 2b and the orbiting spiral wrap 3b engaged together creating a compression chamber 4 in between the fixed spiral wrap 2b and the orbiting spiral wrap 3b. The orbiting scroll 3 revolves relatively to the fixed scroll 2 to compress refrigerant that is supplied through the suction pipe 13 entering the compression chamber 4.

[0014] The fixed scroll 2 has the fixed spiral warp 2b extended from one side of the fixed base 2a where a suction port 6 is formed penetrated through the fixed base 2a near the peripheral edge supporting the assembly of the suction pipe 13 to supply refrigerant into the compression chamber 4. At the central portion of the fixed base 2a a discharge port 7 is formed, through which the refrigerant compressed into a high pressure is discharged out to a space 18. At the outlet opening of the discharge port 7, there is a valve, which is not shown in the figure, for covering the outlet opening and preventing backflow of refrigerant, and the valve is lifted when refrigerant in the compression chamber 4 is compressed to a high-level pressure. The fixed scroll 2 is fixed to the inside of the shell 12 through a frame 17, where the frame 17 has a through hole at the central portion for supporting the orbiting scroll 3 while supporting the rotational shaft 15.

[0015] The orbiting scroll 3 has the orbiting spiral wrap 3b extended from one side of the orbiting base 3a while on the other side, an orbiting bearing portion 3c is formed at the central portion extending hollowly to receive the assembly of the rotational shaft 15 of the drive mechanism portion 11. As the drive mechanism portion 11 operates, the rotational shaft 15 rotates, and the orbiting scroll 3 performs eccentric rotary motion revolving relatively to the fixed scroll 2. The drive mechanism portion 11 supplies lubricant from the reservoir 16 to the orbiting bearing portion 3 c in order to drive the orbiting scroll 3.

[0016] The compression chamber 4 is formed by the fixed spiral wrap 2b and the orbiting spiral wrap 3b engaging together. The refrigerant enters the compression chamber 4 from the suctionpipe 13 passing through the suction port 6 in the fixed scroll 2. The compression chamber 4 compresses the refrigerant by decreasing its volume while moving from the outer circumferential portion toward the center direction along with the eccentric rotary motion of the orbiting scroll 3. The compressed refrigerant in the compression chamber 4 is discharged from the discharge port 7 provided in the fixed scroll 2, against the valve into the space 18, and then discharged through the discharge pipe 14 to the outside of the shell 12.

[0017] The scroll compressor 1 according to this embodiment further includes an injection mechanism portion 5 for injecting additional refrigerant to the compression chamber 4 to reduce the temperature of refrigerant inside the scroll compressor 1, and the injection mechanism portion 5 is provided connecting to the compression mechanism portion 10. The injection mechanism portion 5 includes an injection pipe 5a and injection ports 5b wherein the additional refrigerant is supplied from the injection pipe 5a through injection ports 5b and enters the compression chamber 4. The injection ports 5b are provided in the fixed base 2a for injecting refrigerant to the compression chamber 4.

[0018] The relationship of the fixed scroll 2, the orbiting scroll 3 and the injection ports 5b of the scroll compressor 1 is shown in Fig. 3. The compression chamber 4 has a first compression chamber 4a and a second chamber 4b, the first compression chamber 4a being formed by an inward face of the fixed spiral wrap 2b and an outward face of the orbiting spiral wrap 3b, the second compression chamber 4b being formed by an outward face of the fixed spiral wrap 2b and an inward face of the orbiting spiral wrap 3b. When the orbiting scroll 3 operates by revolving, the refrigerant supplied from the suction port 6 enters the first compression chamber 4a and second compression chamber 4b relatively according to the eccentric rotary revolving motion toward the center direction. The injection ports 5b comprises a first injection port 5c and a second injection port 5d, which are neighbouring each other in radial direction in the fixed base 2a for injecting refrigerant to the compression chamber 4. Throughout this disclosure, “neighboring” means that the first injection port 5c and the second injection port 5d have a position where they overlap or diagonal with each other in radial direction, or the centers of the first injection port 5c and the second injection port 5d are in the same alignment which extends in radial direction, and the first inj ection port 5c and the second inj ection port 5d are adj acent to each other without being separated by more than their inner diameter. Injection ports 5b may have at least one first injection port 5c and at least one second injection port 5d.

[0019] The first injection port 5c and the second injection port 5d are in oval shape in this embodiment. Each of injection ports 5b may be in a geometrical shape including round shape or elongate shape, and their widths in radial direction are the same as or smaller than the width of the orbiting scroll 3. In this embodiment, the first injection port 5c and the second injection port 5d have, for example, the same shape. The first injection port 5c and the second injection port 5d are provided in between the outermost fixed spiral wrap 2b and an inwardly adjacent fixed spiral wrap 2b, and the first injection port 5c and the second injection port 5d are positioned in a range of a quarter of a distance from the inward face of the outermost fixed spiral wrap 2b to a quarter of a distance from the outward face of the inwardly adjacent fixed spiral wrap 2b. The first injection port 5c is positioned in a range of a quarter of the distance between the outermost fixed spiral wrap 2b and the inwardly adjacent fixed spiral wrap 2b, which is from an inward face of the outermost fixed spiral wrap 2b to less than a half of the distance between the outermost fixed spiral wrap 2b and the inwardly adjacent fixed spiral wrap 2b. The second injection port 5d is positioned in a range of a quarter of the distance between the outermost fixed spiral wrap 2b and the inwardly adjacent fixed spiral wrap 2b, which is from an outward face of the inwardly adjacent fixed spiral wrap 2b to less than a half of the distance between the outermost fixed spiral wrap 2b and the inwardly adjacent fixed spiral wrap 2b. As a result, these injection ports 5b operate according to the above-mentioned eccentric rotary motion of the orbiting scroll 3 in the specified range for better efficiency of the scroll compressor 1.

[0020] Hereinafter, the operation of the orbiting scroll 3 is described briefly. The orbiting scroll 3 performs eccentric rotary motion revolving relatively to the fixed scroll 2, wherein refrigerant from the suction port 6 enters the compression chamber 4 moving from the outer circumferential portion toward the center direction, and the first injection port 5c and the second injection port 5d inject refrigerant to the first compression chamber 4a and the second compression chamber 4b according to a crank angle of the eccentric rotary motion of the orbiting scroll 3. In the present invention, the first injection port 5c and the second injection port 5d inject refrigerant to the first compression chamber 4a and the second compression chamber 4b respectively at the same time when the crank angle is in a specified range as further described later.

[0021] The relationship among the fixed scroll 2, the orbiting scroll 3 and the injection ports 5b at each crank angle is described with Figs. 4 to 6. As shown in Fig. 4, the orbiting scroll 3 performs eccentric rotary revolving motion in full cycle and at each specific angle. The orbiting scroll 3positioned at a crank angle of 0 degree where an inward face of the end of the orbiting spiral wrap 3b contacts the outward face of the fixed spiral wrap 2b. The orbiting scroll 3 revolves to the position at a crank angle of 180 degrees where an outward face of the end of the orbiting spiral wrap 3b contacts the inward face of the fixed spiral wrap 2b. The orbiting scroll 3 then travels from the position of -180 degrees returning to the position of 0 degrees. The negative symbol indicates the vector direction of the orbiting scroll 3. The specified range of the crank angle of the orbiting scroll 3 where the first injection port 5c and the second injection port 5d inject refrigerant to the first compression chamber 4a and the second compression chamber 4b respectively at the same time, which starts at a first stage of the compression where refrigerant pressure is more than pressure inside the compression chamber 4.

[0022] As shown in Fig. 5, from the crank angle of 0 degrees to less than 10 degrees, only the first injection port 5c is opening to the first compression chamber 4a so that the first injection port 5c injects refrigerant to the first compression chamber 4a only. During the crank angle of 10 degrees to 30 degrees, the first injection port 5c is opening to the first compression chamber 4a and the second injection port 5d is also opening to the second compression chamber 4b, such that the first inj ection port 5c and the second inj ection port 5d inj ect refrigerant to the first compression chamber 4a and the second compression chamber 4b respectively at the same time, However, since each injection port is partially covered with the orbiting spiral wrap 3b, the pressure of the compression chamber 4 is lower than the injection pressure, resulting in better efficiency of the performance of the scroll compressor 1. During the crank angle of more than 30 degrees to less than 180 degrees, the first injection port 5c and / or the second injection port 5d are opening to the second compression chamber 4b so that the first injection port 5c and / or the second injection port 5d inject refrigerant to the second compression chamber 4b only.

[0023] As shown in Fig. 6, during the crank angle of -180 degrees to more than -170 degrees, only the second injection port 5d is opening to the second compression chamber 4b so that the second injection port 5d injects refrigerant to the second compression chamber 4b only. During the crank angle of -170 degrees to -160 degrees, the first injection port 5c is opening to the first compression chamber 4a and the second injection port 5d is also opening to the second compression chamber 4b, such that the first injection port 5c and the second injection port 5d inject refrigerant to the first compression chamber 4a and the second compression chamber 4b respectively at the same time. However, since each injection port is partially covered with the orbiting spiral wrap 3b, thepressure of the compression chamber 4 is lower than the injection pressure, resulting in better efficiency of the performance of the scroll compressor 1.

[0024] Returning to Fig 4, during the crank angle of less than -160 degrees to more than 0 degrees, the first injection port 5c and / or the second injection port 5d are opening to the first compression chamber 4a so that the first injection port 5c and / or the second injection port 5d inject refrigerant to the first compression chamber 4a only. There are two overlap periods that the first injection port 5c and the second injection port 5d inject refrigerant to the first compression chamber 4a and the second compression chamber 4b at the same time, where the crank angle is 10 to 30 degrees and -170 to -160 degrees. The overlap period of having the injection ports 5b inject refrigerant to the first compression chamber 4a and the second compression chamber 4b at the same time increases the efficiency of the scroll compressor 1 by increasing the refrigerant injection volume and also decreasing the temperature of the refrigerant in the compression chamber 4, which results in better efficiency.

[0025] Fig. 7 shows an injection range of the injection ports 5b at each crank angle of the eccentric rotary motion of the orbiting scroll 3 revolving relatively to the fixed scroll 2 of the scroll compressor 1. The injection port 5b continuously injects refrigerant to the compression chamber 4 throughout the orbiting scroll revolving motion where a range of the orbiting scroll revolving motion is not more than 200 degrees. The first injection port 5c continuously injects refrigerant in the crank angle period of the orbiting scroll revolving motion of -170 degrees to 30 degrees, where the second injection port 5d continuously inject refrigerant in the crank angle period of the orbiting scroll revolving motion of 10 degrees to 200 degrees. As described above, in the overlap period at the crank angle of 10 degrees to 30 degrees and -170 degrees to -160 degrees, the first injection port 5c and the second injection port 5d inject refrigerant to the first compression chamber 4a and the second compression chamber 4b at the same time. This results in increasing the refrigerant injection volume, and also the orbiting scroll revolving motion being not more than 200 degrees results in the refrigerant of a sufficient volume for the efficiency of the compression process. Furthermore, the injection period of this embodiment is shorter compared to other commercial scroll compressors. The decreasing of the injection period helps increase the efficiency of the scroll compressor 1 by reducing the injection flow loss and reducing the duration of energy loss occurrence, resulting in increasing the compression efficiency. The decreasing of the injection period also helps in maintaining the pressure within the scroll compressor 1, in which the injection pressure is more than the suction pressure such that the injection flow loss is decreased, and / orhelping in maintaining the injection mass flow rate by reducing the injection flow loss as an improvement of the injection efficiency. The scroll compressor 1 operates with better efficiency and reduces the energy consumption for the operation.(Embodiment 2)

[0026] Now, a scroll compressor 1 A according to Embodiment 2 will be described with Figs. 8 to 9. Figs. 8 to 9 show a fixed scroll 21 and an orbiting scroll 31 of the scroll compressor 1 A with multiple injection ports 51, wherein a compression mechanism portion 19 of Embodiment 2 has the same elements as those in Embodiment 1 but with multiple injection ports 51 indicated in said figures. Embodiment 2 is an example of having multiple injection ports 51 but with the same operating mechanism applied to Embodiment 1. Those same elements may not be shown in figures. The compression mechanism portion 19 includes the fixed scroll 21 and the orbiting scroll 31. The fixed scroll 21 includes a fixed base 21a and a fixed spiral wrap 21b extending from one side of the fixed base 21a. The orbiting scroll 31 includes an orbiting base 31a and an orbiting spiral wrap 31b extending from one side of the orbiting base 31a. The fixed scroll 21 and the orbiting scroll 31 are fitted together where the fixed spiral wrap 21b and the orbiting spiral wrap 3 lb are engaged together creating a compression chamber 41 in between the fixed spiral wrap 21b and the orbiting spiral wrap 31b.

[0027] The multiple injection ports 51 are provided in the fixed base 21a for injecting refrigerant to the compression chamber 41. The injection ports 51 in Embodiment 2 comprise two first injection ports 51a and two second injection ports 51b. Each of the injection ports 51 is in a round shape and has the same size. Each of the two first injection ports 51a is arranged in the circumferential direction, and each of the two second injection ports 51b is also arranged in the circumferential direction. These two first injection ports 51a and two second injection ports 51b are arranged neighbouring each other in radial direction and inject refrigerant to the compression chamber 41. The orbiting scroll 31 performs eccentric rotary motion revolving relatively to the fixed scroll 21, causing refrigerant from the suction port to enter the compression chamber 41 moving from the outer circumferential portion toward the center direction, and the first injection ports 51a and second injection ports 51b inject refrigerant to the first compression chamber 41a and the second compression chamber 41b according to a crank angle of the eccentric rotary motion of the orbiting scroll 31.

[0028] In Embodiment 2, the two first injection ports 51a and two second injection ports 51b are provided in the fixed base 21a neighboring each other in radial direction and provided in between the outermost fixed spiral wrap 21b and an inwardly adjacent fixed spiral wrap 21b, wherein are positioned in a range of a quarter of a distance from the inward face of the outermost fixed spiral wrap 21b to a quarter of a distance from the outward face of the inwardly adjacent fixed spiral wrap 21b. The two first injection ports 51a are positioned in a range of a quarter of the distance between the outermost fixed spiral wrap 21b and the inwardly adjacent fixed spiral wrap 21b, which is from an inward face of the outermost fixed spiral wrap 21b to less than a half of the distance between the outermost fixed spiral wrap 21b and the inwardly adjacent fixed spiral wrap 21b. The two second injection ports 51b are positioned in a range of a quarter of the distance between the outermost fixed spiral wrap 21b and the inwardly adjacent fixed spiral wrap 21b, which is from an outward face of the inwardly adjacent fixed spiral wrap 21b to less than a half of the distance between the outermost fixed spiral wrap 21b and the inwardly adjacent fixed spiral wrap 21b. As a result, these injection ports 51 operate according to the above-mentioned eccentric rotary motion of the orbiting scroll 31 in the specified range for better efficiency of the scroll compressor.

[0029] The orbiting scroll revolving motion is operated according to Embodiment 1 resulting in the scroll compressor 1. Fig. 8 and Fig. 9 showed the revolving motion of the orbiting scroll 31 at the crank angle of 20 degrees and -160 degrees respectively. As a result, the scroll compressor 1 A would have better efficiency and improving the coefficient of performance.

[0030] The scroll compressor disclosed throughout this description is an asymmetric oval scroll compressor. In addition, the first injection port and the second injection port of the scroll compressor according to this invention in a workpiece can have a similar geometrical shape or different geometrical shapes. The scroll compressor according to this invention may be used under the low temperature applications such as an industrial cooler or heat pump. Although the preferred embodiments of this invention have been disclosed, a person skill in this art would recognize that certain modifications would come within the scope of this invention.[Reference Signs List]

[0031] 1: scroll compressor, 1A: scroll compressor, 2: fixed scroll, 2a: fixed base, 2b: fixed spiral wrap, 3: orbiting scroll, 3a: orbiting base, 3b: orbiting spiral wrap, 3c: orbiting bearing portion, 4: compression chamber, 4a: first compression chamber, 4b: second compression chamber, 5: injection mechanism portion, 5a: injection pipe, 5b: injection ports, 5c: first injection port, 5d:second injection port, 6: suction port, 7: discharge port, 10: compression mechanism portion, 11: drive mechanism portion, 12: shell, 13: suction pipe, 14: discharge pipe, 15: rotational shaft, 16: reservoir, 17: frame, 18: space, 19: compression mechanism portion, 21: fixed scroll, 21a: fixed base, 21b: fixed spiral wrap, 31: orbiting scroll, 31a: orbiting base, 31b: orbiting spiral wrap, 41: compression chamber, 41a: first compression chamber, 41b: second compression chamber, 51: injection port, 51a: first injection port, 51b: second injection port

Claims

Claims

1. A scroll compressor comprising:a fixed scroll including a fixed base and a fixed spiral wrap extending from the fixed base; an orbiting scroll including an orbiting base and an orbiting spiral wrap extending from the orbiting base, the fixed spiral wrap and the orbiting spiral wrap being fitted together creating a compression chamber, and the orbiting scroll revolving relatively to the fixed scroll to compress refrigerant that is supplied to the compression chamber; whereinthe compression chamber has a first compression chamber and a second compression chamber, the first compression chamber being formed by an inward face of the fixed spiral wrap and an outward face of the orbiting spiral wrap, and the second compression chamber being formed by an outward face of the fixed spiral wrap and an inward face of the orbiting scroll wrap;at least two injection ports are provided in the fixed base for injecting refrigerant to a compression chamber;wherein a first injection port and a second injection port inject refrigerant to the first compression chamber and the second compression chamber respectively at the same time when a crank angle of the orbiting scroll is in a specified range and the first injection port, and the second injection port are neighboring each other in radial direction.

2. The scroll compressor according to claim 1, wherein the specified range of the crank angle of the orbiting scroll, where the first injection ports and the second injection ports inject refrigerant to the first compression chamber and the second compression chamber respectively at the same time, starts at a first stage of the compression where a refrigerant pressure is more than a pressure inside the compression chamber.

3. The scroll compressor according to claim 1 or 2, wherein the specified range of the crank angle of the orbiting scroll is 10 degrees to 30 degrees.

4. The scroll compressor according to claim 1 or 2, wherein the specified range of the crank angle of the orbiting scroll is -170 degrees to -160 degrees.

5. The scroll compressor according to claim 1, wherein the injection ports are provided in between an outermost fixed spiral wrap and an inwardly adjacent fixed spiral wrap, in a range ofa quarter of a distance from the inward face of the outermost fixed spiral wrap to a quarter of a distance from the outward face of the inwardly adjacent fixed spiral wrap.

6. The scroll compressor according to claim 1 or 5, wherein the first injection port is positioned in a range of a quarter of the distance between the outermost fixed spiral wrap and the inwardly adjacent fixed spiral wrap, which is from an inward face of the outermost fixed spiral wrap to less than a half of the distance between the outermost fixed spiral wrap and the inwardly adjacent fixed spiral wrap; and the second injection port is positioned in a range of a quarter of the distance between the outermost fixed spiral wrap and the inwardly adjacent fixed spiral wrap, which is from an outward face of the inwardly adjacent fixed spiral wrap to less than a half of the distance between the outermost fixed spiral wrap and the inwardly adjacent fixed spiral wrap.

7. The scroll compressor according to any of claims 1, 5 or 6, wherein the injection ports continuously inject refrigerant to the compression chamber throughout the orbiting scroll revolving motion where the range of the orbiting scroll revolving motion is not more than 200 degrees.

8. The scroll compressor according to any of claims 1 to 5, 6 or 7, wherein the injection ports include a round or elongate shape.

9. The scroll compressor according to claim 1, wherein the scroll compressor is an asymmetric oval scroll compressor.

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