compressor

Abstract

To improve compression efficiency of a compressor.SOLUTION: A compressor includes: a front head (31) having a discharge port (50) for leading out a fluid from a compression chamber (36) and partitioning the inside of the compression chamber (36) from the outside; a valve body (61) which opens or closes the discharge port (50); a valve presser (65) which contacts with the valve body (61) from a side opposite to the discharge port when the discharge port (50) is opened; and a piston (38) which rotates so as to compress the fluid suctioned into the compression chamber (36). A first coat (652) is formed at a valve body (61) side surface of the valve presser (65), and a contact angle between the valve presser and a refrigeration oil is set large compared to a case where the first coat (652) is not formed.SELECTED DRAWING: Figure 5A

Description

Technical Field

[0001] The present disclosure relates to a compressor having a valve body that opens and closes a discharge port for discharging fluid from a compression chamber, and a valve retainer that abuts the valve body from the side opposite to the discharge port when the discharge port is open.

Background Art

[0002] Patent Document 1 discloses a compressor having a discharge port for discharging fluid from a compression chamber, a partition member that partitions the inside and outside of the compression chamber, a valve body that opens and closes the discharge port, a valve retainer that abuts the valve body from the side opposite to the discharge port when the discharge port is open, and a rotating member that rotates to compress the fluid sucked into the compression chamber.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In Patent Document 1, since the valve body adheres to the valve retainer by the meniscus force through an oil film of refrigeration machine oil in the open state of the discharge port, when the pressure of the fluid in the compression chamber decreases, it takes time for the valve body to separate from the valve retainer, and there is a risk of reducing the compression efficiency due to the delay in closing the valve body.

[0005] An object of the present disclosure is to improve the compression efficiency of a compressor.

Means for Solving the Problems

[0006] A first aspect of the present disclosure is a compressor having a discharge port (50) for discharging fluid from a compression chamber (36), a partition member (31) separating the inside and outside of the compression chamber (36), a valve body (61) for opening and closing the discharge port (50), a valve retainer (65) that contacts the valve body (61) from the side opposite the discharge port when the discharge port (50) is open, and a rotating member (38) that rotates to compress the fluid drawn into the compression chamber (36), wherein at least one of the surfaces of the valve body (61) on the side of the valve retainer (65) and the surface of the valve retainer (65) on the side of the valve body (61) is formed on the surface, and the contact angle with the refrigerant oil is larger than when the coating (652,612) is not formed.

[0007] In the first embodiment, compared to the case where the above-mentioned coating (652, 612) is not formed, the meniscus force between the valve body (61) and the valve retainer (65) can be reduced. Therefore, when the fluid pressure in the compression chamber (36) decreases while the discharge port (50) is open, the valve body (61) can be quickly detached from the valve retainer (65) and closed. Consequently, the compression efficiency can be increased.

[0008] A second aspect of this disclosure is characterized in that, in the first aspect, the maximum rotational speed of the rotating member (38) is 118 rps or more.

[0009] In the second embodiment, the impact of delayed closing of the valve body (61) on the compression efficiency is greater compared to the case where the maximum rotational speed of the rotating member (38) is less than 118 rps. However, as described above, since the valve body (61) can be released from the valve retainer (65) earlier and put into a closed state, the decrease in compression efficiency caused by delayed closing of the valve body (61) can be suppressed.

[0010] A third aspect of this disclosure is characterized in that, in the second aspect, the maximum rotational speed of the rotating member (38) is 130 rps or more.

[0011] In the third embodiment, the impact of delayed closing of the valve body (61) on the compression efficiency is greater compared to the case where the maximum rotational speed of the rotating member (38) is less than 130 rps. However, as described above, since the valve body (61) can be released from the valve retainer (65) earlier and put into a closed state, the decrease in compression efficiency caused by delayed closing of the valve body (61) can be suppressed.

[0012] A fourth aspect of the present disclosure is characterized in that, in any one of the first to third aspects, the maximum rotational speed of the rotating member (38) is 100 rps or more, and the contact angle of at least one surface with the refrigerant oil is 40 deg or more.

[0013] In the fourth embodiment, even if the maximum rotational speed of the rotating member (38) is set to 100 rps or more, the valve body (61) can be released from the valve retainer (65) and closed more quickly than when the contact angle between the refrigerant oil and at least one surface is less than 40 deg, thereby suppressing the decrease in compression efficiency caused by the delayed closing of the valve body (61).

[0014] A fifth aspect of the present disclosure is characterized in that, in the fourth aspect, the maximum rotational speed of the rotating member (38) is 118 rps or more, and the contact angle between at least one surface and the refrigerant oil is 45 deg or more.

[0015] In the fifth embodiment, even if the maximum rotational speed of the rotating member (38) is set to 118 rps or more, the valve body (61) can be released from the valve retainer (65) and closed earlier compared to the case where the contact angle between the refrigerant oil and at least one surface is less than 45 deg, thereby suppressing the decrease in compression efficiency caused by the delayed closing of the valve body (61).

[0016] A sixth aspect of the present disclosure is characterized in that, in the fifth aspect, the maximum rotational speed of the rotating member (38) is 130 rps or more, and the contact angle of at least one surface with the refrigerant oil is 49 deg or more.

[0017] In the sixth aspect, even when the maximum rotational speed of the rotating member (38) is 130 rps or more, the valve body (61) can be separated from the valve retainer (65) faster and closed compared to the case where the contact angle with the refrigeration machine oil on at least one surface is less than 49 deg. Therefore, it is possible to suppress a decrease in compression efficiency due to a delay in closing of the valve body (61).

[0018] A seventh aspect of the present disclosure is characterized in that, in the sixth aspect, the maximum rotational speed of the rotating member (38) is 150 rps, and the contact angle of at least one surface with refrigeration machine oil is 60 deg or more.

[0019] In the seventh aspect, even when the maximum rotational speed of the rotating member (38) is 150 rps or more, the valve body (61) can be separated from the valve retainer (65) faster and closed compared to the case where the contact angle with the refrigeration machine oil on at least one surface is less than 60 deg. Therefore, it is possible to suppress a decrease in compression efficiency due to a delay in closing of the valve body (61).

[0020] An eighth aspect of the present disclosure is characterized in that, in any one of the first to seventh aspects, the coating (652, 612) is made of a PTFE resin, a PFA resin, an FEP resin, or an ETFE resin.

Brief Description of Drawings

[0021] [Figure 1] FIG. 1 is a schematic configuration diagram of a refrigerant circuit included in the refrigeration apparatus of Embodiment 1. [Figure 2] FIG. 2 is a longitudinal sectional view of the compressor of Embodiment 1. [Figure 3] FIG. 3 is a sectional view of the compression mechanism taken along line A-A in FIG. 2. [Figure 4] FIG. 4 is a plan view of the discharge valve. [Figure 5A] FIG. 5A is a sectional view showing a main part of the compression mechanism taken along line B-B in FIG. 4, showing a state where the discharge valve is closed. [Figure 5B] FIG. 5B is a sectional view showing a main part of the compression mechanism taken along line B-B in FIG. 4, showing a state where the discharge valve is open. [Figure 6] Figure 6 is a cross-sectional view showing the main parts of the compression mechanism along the CC line in Figure 4. [Figure 7] Figure 7 is a table showing the relationship between the maximum piston rotational speed and the minimum contact angle between the valve retainer and the refrigerant oil. [Figure 8] Figure 8 is a graph showing the relationship between the maximum rotational speed of the piston and the minimum contact angle between the valve retainer and the refrigerant oil. [Figure 9A] Figure 9A is a diagram corresponding to Figure 5A of Embodiment 2. [Figure 9B] Figure 9B is a diagram corresponding to Figure 5B of Embodiment 2. [Figure 10] Figure 10 is a diagram corresponding to Figure 6 of Embodiment 2. [Figure 11A] Figure 11A is a diagram corresponding to Figure 5A of Embodiment 3. [Figure 11B] Figure 11B is a diagram corresponding to Figure 5B of Embodiment 3. [Figure 12] Figure 12 is a diagram corresponding to Figure 6 of Embodiment 3. [Modes for carrying out the invention]

[0022] Embodiments of this disclosure will be described below with reference to the drawings. These embodiments are essentially preferred examples and are not intended to limit the scope of the invention, its applications, or uses. The drawings are for conceptual purposes only. Therefore, dimensions, ratios, or numbers in the drawings may be exaggerated or simplified to facilitate understanding of the technology of this disclosure.

[0023] (Embodiment 1) -Refrigeration equipment- As shown in Figure 1, the refrigeration system (1) has a refrigerant circuit (2) filled with refrigerant. The refrigerant circuit (2) comprises a compressor (10), a heat exchanger (3), a pressure reducing mechanism (4), and an evaporator (5) according to Embodiment 1 of the present disclosure. The pressure reducing mechanism (4) is, for example, an expansion valve. The refrigerant circuit (2) circulates the refrigerant to perform a vapor compression type refrigeration cycle.

[0024] In a refrigeration cycle, the gaseous refrigerant compressed by the compressor (10) releases heat into the air in the heat exchanger (3). At this time, the refrigerant liquefies and changes into liquid refrigerant. The liquid refrigerant that has released heat is depressurized by the depressurization mechanism (4). The depressurized liquid refrigerant evaporates in the evaporator (5). At this time, the refrigerant vaporizes and changes into gaseous refrigerant. The evaporated gaseous refrigerant is drawn into the compressor (10). The compressor (10) compresses the drawn-in gaseous refrigerant. Refrigerant is an example of a fluid.

[0025] The refrigeration device (1) is, for example, an air conditioning device. The air conditioning device may be a combined cooling and heating unit that switches between cooling and heating. In this case, the refrigerant circuit (2) has a switching mechanism that switches the direction of circulation of the refrigerant. The switching mechanism is, for example, a four-way switching valve. The air conditioning device may be a cooling-only unit or a heating-only unit.

[0026] Furthermore, the refrigeration device (1) may be a water heater, a chiller unit, or a cooling device that cools the air inside the storage unit. The cooling device is a device that cools the air inside a refrigerator, freezer, container, etc.

[0027] - Compressor - As shown in Figure 2, the compressor (10) in this example is a fully enclosed rotary compressor.

[0028] The compressor (10) comprises a casing (11), an electric motor (20), and a compression mechanism (30). The electric motor (20) and the compression mechanism (30) are housed inside the casing (11). The compression mechanism (30) is located at the bottom of the casing (11). The electric motor (20) is located above the compression mechanism (30).

[0029] <Casing> The casing (11) is a cylindrical sealed container with both ends closed. The casing (11) is installed in an upright position. The casing (11) comprises a body (12), an upper end plate (13), and a lower end plate (14). The body (12) is formed in a cylindrical shape. The upper end plate (13) closes the upper end opening of the body (12). The lower end plate (14) closes the lower end opening of the body (12).

[0030] An intake pipe (15) is attached to the lower part of the body (12). The intake pipe (15) passes through the body (12) of the casing (11) and is connected to the compression mechanism (30). A discharge pipe (16) is attached to the upper end plate (13). The discharge pipe (16) passes through the upper end plate (13) and opens into the space above the electric motor (20) inside the casing (11). An oil reservoir (17) is formed at the bottom of the casing (11). Refrigerant oil is stored in the oil reservoir (17).

[0031] <Electric motor> The electric motor (20) comprises a stator (21), a rotor (22), and a drive shaft (23). The stator (21) and rotor (22) are each formed in a cylindrical shape. The stator (21) is fixed to the body (12) of the casing (11). The rotor (22) is positioned in the hollow part of the stator (21). The drive shaft (23) is inserted through the hollow part of the rotor (22). The rotor (22) is fixed to the drive shaft (23) and rotates integrally with the drive shaft (23).

[0032] The drive shaft (23) is a rod-shaped member that extends in the vertical direction. The drive shaft (23) comprises a main shaft portion (24) and an eccentric portion (25). The eccentric portion (25) is positioned near the lower end of the main shaft portion (24). The eccentric portion (25) is formed to have a larger diameter than the main shaft portion (24). The axis of the eccentric portion (25) is eccentric with respect to the axis of the main shaft portion (24). Although not shown, an oil supply passage is formed in the drive shaft (23). The oil supply passage is a passage for supplying refrigerant oil to the sliding part of the compressor (10).

[0033] A pump (26) is provided at the lower end of the main shaft (24). The pump (26) is immersed in the refrigerant oil in the oil reservoir (17). When the drive shaft (23) rotates, the refrigerant oil in the oil reservoir (17) is pumped up by the pump (26) to the oil supply passage of the drive shaft (23). The pumped refrigerant oil is supplied through the oil supply passage to the various sliding parts of the compressor (10), such as the compression mechanism (30), the first bearing (31a), and the second bearing (33a).

[0034] <Compression mechanism> The compression mechanism (30) is a so-called oscillating piston type rotary fluid machine. The compression mechanism (30) comprises a front head (31), a cylinder (32), a rear head (33), a piston (38) as a rotating member, and a pair of bushings (41) (see Figure 3). The front head (31), cylinder (32), and rear head (33) are fastened to each other by bolts to form a housing (34).

[0035] The front head (31) is a component that closes the upper end surface of the cylinder (32). A first bearing (31a) is provided in the center of the front head (31). The first bearing (31a) is formed in a cylindrical shape and protrudes upward. The first bearing (31a) constitutes a sliding bearing. The drive shaft (23) is inserted through the hollow portion of the first bearing (31a). The first bearing (31a) is located above the eccentric portion (25) of the drive shaft (23) and rotatably supports the main shaft portion (24).

[0036] The rear head (33) is a component that closes the lower end surface of the cylinder (32). A second bearing (33a) is provided in the center of the rear head (33). The second bearing (33a) is formed in a cylindrical shape and protrudes downward. The second bearing (33a) constitutes a sliding bearing. The drive shaft (23) is inserted through the hollow portion of the second bearing (33a). The second bearing (33a) is located below the eccentric portion (25) of the drive shaft (23) and rotatably supports the main shaft portion (24).

[0037] The cylinder (32) is a thick-walled disc-shaped member. A cylinder bore (32a) is formed in the center of the cylinder (32). The cylinder bore (32a) is a circular hole that penetrates the cylinder (32) in the thickness direction. The cylinder bore (32a) is enclosed by a front head (31) and a rear head (33). The housing (34), together with the piston (38) housed in the cylinder bore (32a), forms a compression chamber (36). Therefore, the front head (31) constitutes a partition member that separates the inside and outside of the compression chamber (36). The cylinder (32) is fixed to the body (12) of the casing (11) in an orientation with the center line of the cylinder bore (32a) facing vertically.

[0038] As shown in Figure 3, the cylinder (32) has a bushing hole (32b) and a blade hole (32c). The bushing hole (32b) and the blade hole (32c) penetrate the cylinder (32) in the thickness direction. The bushing hole (32b) and the blade hole (32c) are each formed in a substantially circular shape. The bushing hole (32b) opens into the compression chamber (36). The blade hole (32c) communicates with the bushing hole (32b). The bushing hole (32b) is located between the compression chamber (36) and the blade hole (32c).

[0039] A pair of bushings (41) are fitted into the bushing hole (32b). Each bushing (41) is a semi-cylindrical member. The flat surfaces of the pair of bushings (41) face each other with a gap between them. The pair of bushings (41) can pivot about the center line of the bushing hole (32b). The pair of bushings (41) restrict the rotation of the piston (38) by sandwiching the blade (43), which will be described later.

[0040] The piston (38) comprises a roller (39) and a blade (43). The roller (39) is a cylindrical member. The eccentric portion (25) of the drive shaft (23) is rotatably fitted into the hollow portion of the roller (39). The outer circumferential surface (40) of the roller (39) slides against the inner circumferential surface (35) of the cylinder (32). A compression chamber (36) is formed between the outer circumferential surface (40) of the roller (39) and the inner circumferential surface (35) of the cylinder (32). The compression chamber (36) is a space for compressing gaseous refrigerant.

[0041] The blade (43) is formed in a flat plate shape. The blade (43) is provided on the outer circumferential surface (40) of the roller (39) and extends radially outward from the roller (39). The blade (43) divides the compression chamber (36) into a high-pressure chamber (36a) and a low-pressure chamber (36b). The blade (43) is sandwiched between a pair of bushings (41) so as to be able to move back and forth and is inserted into a blade hole (32c). The blade (43) is supported by the cylinder (32) via the pair of bushings (41).

[0042] An intake port (42) is formed in the cylinder (32). The intake port (42) penetrates the cylinder (32) radially and communicates with the low-pressure chamber (36b) of the compression chamber (36). One end of the intake port (42) opens to the inner circumferential surface (35) of the cylinder (32). The open end of the intake port (42) on the inner circumferential surface (35) of the cylinder (32) is located adjacent to the bush (41) (to the right of the bush (41) in Figure 3). On the other hand, an intake pipe (15) is inserted into the other end of the intake port (42).

[0043] A discharge port (50) is formed in the front head (31). The discharge port (50) penetrates the front head (31) and communicates with the high-pressure chamber (36a) of the compression chamber (36). The discharge port (50) is a port for discharging gaseous refrigerant from the compression chamber (36). On the lower surface of the front head (31), the open end of the discharge port (50) is positioned on the opposite side of the bush (41) from the intake port (42) (to the left of the bush (41) in Figure 3).

[0044] The compressor (10) draws low-pressure gaseous refrigerant from the suction pipe (15) through the suction port (42) into the compression chamber (36). The piston (38) is rotationally driven by the electric motor (20) to change the volume of the compression chamber (36) (high-pressure chamber (36a) and low-pressure chamber (36b)). This compresses the gaseous refrigerant drawn into the compression chamber (36). The compressor (10) discharges the high-pressure gaseous refrigerant compressed in the compression chamber (36) from the discharge port (50) and through the internal space of the casing (11) through the discharge pipe (16).

[0045] <Discharge valve> A discharge valve (60) is provided on the upper surface of the front head (31). The discharge valve (60) opens and closes the discharge port (50). The discharge valve (60) is composed of a reed valve. As shown in Figures 5A, 5B and 6, the discharge valve (60) is mounted on the upper surface of the front head (31). As also shown in Figure 4, the discharge valve (60) comprises a valve body (61), a valve retainer (65), and a fixing pin (67). The base end (62) of the valve body (61) and the base end (66) of the valve retainer (65) are both fixed to the front head (31) by a fixing pin (67) such as a bolt.

[0046] The valve body (61) is a long, flat, thin plate-shaped member. The valve body (61) is composed of a valve body (611) made of a metal such as spring steel or iron. The valve body (61) is flexible. The valve body (61) is installed so as to cover the outflow end (52) of the discharge port (50). The valve body (61) closes the discharge port (50) by covering the outflow end (52) of the discharge port (50) and opens the discharge port (50) by floating above the outflow end (52) of the discharge port (50). The valve body (61) comprises a base end (62), a valve neck (63), and a valve head (64).

[0047] A retaining hole (62a) is formed in the base end (62) of the valve body (61). A fixing pin (67) is inserted through the retaining hole (62a). The valve neck (63) of the valve body (61) is thinner than the base end (62) and the valve head (64). The valve head (64) constitutes the tip of the valve body (61). The valve head (64) is the part of the valve body (61) that contacts the outflow end (52) of the discharge port (50). The valve head (64) is formed in a circular shape with a larger diameter than the outflow end (52) of the discharge port (50).

[0048] The valve retainer (65) is formed in an elongated plate shape corresponding to the shape of the valve body (61). A retaining hole (66a) is formed at the base end (66) of the valve retainer (65). A fixing pin (67) is inserted through the retaining hole (66a). The valve retainer (65) has a shape that curves upward so as it moves away from the front head (31) towards the tip. The valve retainer (65) is positioned so as to overlap the valve body (61).

[0049] The valve retainer (65) has a thin plate-shaped valve retainer body (651) that forms its main body, and a first coating (652) formed on the surface of the valve retainer body (61) side (discharge port (50) side) of the valve retainer body (651). The valve retainer body (651) is a highly rigid metal component such as iron. This first coating (652) is made of PTFE (polytetrafluoroethylene) resin, PFA (perfluoroalkoxy) resin, FEP (hexafluoropropylene) resin, or ETFE (ethylene tetrafluoroethylene) resin. The first coating (652) is formed by applying a coating agent. By forming the first coating (652) on the surface of the valve retainer (65) in this way, the contact angle between the valve retainer (65) and the refrigerant oil is increased compared to when the first coating (652) is not formed.

[0050] As shown in Figure 5A, when the valve body (61) covers the outlet end (52) of the discharge port (50), the discharge port (50) is in a closed state. When the discharge valve (60) is in a closed state, the front surface (61a) of the valve head (64) of the valve body (61) is in close contact with the periphery of the outlet end (52) of the discharge port (50). On the other hand, as shown in Figures 5B and 6, when the valve body (61) is floating above the outlet end (52) of the discharge port (50), the discharge port (50) is in an open state. When the discharge valve (60) is in an open state, an outlet-side flow path (70) is formed between the outlet end (52) of the discharge port (50) and the valve body (61). The gaseous refrigerant discharged from the discharge port (50) passes through the outlet-side flow path (70).

[0051] -Compressor operation- The operation of the compressor (10) will be explained with reference to Figure 3.

[0052] When the electric motor (20) is energized, the drive shaft (23) rotates clockwise in Figure 3. As the drive shaft (23) rotates, the piston (38) eccentrically rotates while oscillating within the compression chamber (36) with the bush (41) as the pivot point. As the piston (38) rotates eccentrically in this way, low-pressure gaseous refrigerant is drawn into the low-pressure chamber (36b) of the compression chamber (36) through the intake port (42), and the gaseous refrigerant present in the high-pressure chamber (36a) of the compression chamber (36) is compressed.

[0053] Here, the gas pressure in the internal space of the casing (11) (dome pressure) acts on the back of the valve body (61) of the discharge valve (60). Therefore, as long as the gas pressure in the high-pressure chamber (36a) is lower than the dome pressure, the discharge valve (60) remains in the closed state as shown in Figure 5A. Then, as the piston (38) moves and the gas pressure in the high-pressure chamber (36a) gradually increases, when the gas pressure in the high-pressure chamber (36a) exceeds the dome pressure, the valve head (64) of the valve body (61) moves away from the outlet end (52) of the discharge port (50). As a result, the discharge valve (60) becomes open, opening the discharge port (50), as shown in Figure 5B. At this time, the valve retainer (65) contacts the valve body (61) from the side opposite the discharge port. In this state, the valve body (61) adheres to the valve retainer (65) by meniscus force via an oil film of refrigerant oil. Meanwhile, the gaseous refrigerant in the high-pressure chamber (36a) passes through the discharge port (50) and is led out of the housing (34) in the internal space of the casing (11), i.e., outside the compression mechanism (30), through the gap between the outlet end (52) of the discharge port (50) and the valve body (61). The high-pressure gaseous refrigerant led out from the compression mechanism (30) is discharged to the outside of the casing (11) through the discharge pipe (16).

[0054] Then, as the gas pressure in the high-pressure chamber (36a) gradually decreases and falls below the pressure inside the dome, the valve body (61) detaches from the valve retainer (65) and closes the discharge port (50). At this time, since the first coating (652) is formed on the valve retainer (65), the meniscus force between the valve retainer (65) and the refrigerant oil is smaller compared to when the first coating (652) is not formed. Therefore, when the gas pressure in the high-pressure chamber (36a) decreases while the discharge port (50) is open, the valve body (61) can be detached from the valve retainer (65) earlier and closed. Thus, the compression efficiency can be increased.

[0055] Furthermore, when the refrigeration oil is considered as a single liquid bridge formed between two parallel planes, the meniscus force between the valve retainer (65) and the refrigeration oil is expressed by the following approximate formula 1. Here, the meniscus force is F a1Let θ be the contact angle between the valve body (61) and the refrigerant oil, and the contact angle between the valve retainer (65) and the refrigerant oil, γ be the surface tension, h be the distance between the two planes, and R be the radius of the contact circles between the lower and upper planes for the liquid bridge. The derivation method of this formula is disclosed in "Hiroki Taura et al., Meniscus force of liquid bridge formed between two planes (comparison of exact solution and approximate formula), Transactions of the Japan Society of Mechanical Engineers (C series), Vol. 78, No. 790, 2012, URL: https: / / www.jstage.jst.go.jp / article / kikaic / 78 / 790 / 78_2266 / _pdf / -char / ja".

[0056] F a1 = -2πR 2 (γ / h)cosθ ···(1) From the above approximation formula 1, it can be inferred that increasing the contact angle can reduce the meniscus force.

[0057] -Relationship between the maximum rotational speed of the compressor and the contact angle- Figures 7 and 8 show the relationship between the maximum rotational speed of the piston (38) and the minimum contact angle between the valve retainer (65) and the refrigerant oil. The maximum rotational speed defines the maximum rotational speed of the electric motor (20). Increasing the maximum rotational speed of the compressor (10) is preferable to increase the amount of refrigerant circulating in the refrigerant circuit (2) and to ensure the maximum amount of refrigerant circulating. This is advantageous in air conditioning systems for increasing cooling capacity during cooling operation and heating capacity during heating operation.

[0058] On the other hand, increasing the maximum rotational speed increases the impact of delayed closing of the valve body (61) on the compression efficiency. Therefore, it is preferable to set a large contact angle for the valve retainer (65) to reduce the meniscus force between the valve retainer (65) and the refrigerant oil, thereby causing the valve body (61) to detach from the valve retainer (65) earlier. Specifically, by setting the contact angle of the valve retainer (65) with the refrigerant oil to be greater than or equal to the minimum contact angle shown in Figures 7 and 8, the decrease in compression efficiency caused by delayed closing of the valve body (61) can be suppressed compared to when it is set to less than the minimum contact angle. In Figure 4, the tip of the valve retainer (65) corresponding to the valve head (64) is formed in a circular shape with a diameter slightly smaller than the valve head (64), but it may be larger than the valve head (64). The larger the contact area of ​​the valve head (64) with the valve retainer (65), the greater the meniscus force and the greater the effect of suppressing the decrease in compression efficiency.

[0059] For example, if the maximum rotational speed of the piston (38) is 100 rps or more, setting the contact angle of the valve retainer (65) with the refrigerant oil to 40 deg or more allows the valve body (61) to detach from the valve retainer (65) earlier and close compared to when it is less than 40 deg, thereby suppressing the decrease in compression efficiency caused by the delayed closing of the valve body (61).

[0060] Furthermore, when the maximum rotational speed of the piston (38) is 118 rps or higher, setting the contact angle of the valve retainer (65) with the refrigerant oil to 45 deg or higher allows the valve body (61) to detach from the valve retainer (65) earlier and close compared to when it is less than 45 deg, thereby suppressing the decrease in compression efficiency caused by the delayed closing of the valve body (61).

[0061] Furthermore, when the maximum rotational speed of the piston (38) is 130 rps or higher, setting the contact angle of the valve retainer (65) with the refrigerant oil to 49 deg or higher allows the valve body (61) to detach from the valve retainer (65) earlier and close compared to when it is less than 49 deg, thereby suppressing the decrease in compression efficiency caused by the delayed closing of the valve body (61).

[0062] Furthermore, when the maximum rotational speed of the piston (38) is 150 rps, setting the contact angle of the valve retainer (65) with the refrigerant oil to 60 deg or more allows the valve body (61) to detach from the valve retainer (65) earlier and close compared to when it is less than 60 deg, thereby suppressing the decrease in compression efficiency caused by the delayed closing of the valve body (61).

[0063] The contact angle between the valve retainer (65) and the refrigerant oil can be set to be greater than or equal to the minimum contact angle shown in Figures 7 and 8 by satisfying the following equation 2.

[0064] θ ≥ 4.5e ―8 ·N 4 +7.9e ―6 ·N 3 -0.0017N 2 +0.0057N +39.84 ···(2) (Embodiment 2) Figure 9A is a diagram corresponding to Figure 5A of Embodiment 2. In Embodiment 2, as shown in Figures 9B and 10, the first coating (652) is not formed on the valve retainer (65). In addition, a second coating (612) is formed on the surface of the valve body (611) of the valve body on the valve retainer (65) side. This second coating (612) is made of PTFE (polytetrafluoroethylene) resin, PFA (perfluoroalkoxy) resin, FEP (hexafluoropropylene) resin, or ETFE (ethylene tetrafluoroethylene) resin. The second coating (612) is formed by applying a coating agent. By forming the second coating (612) on the surface of the valve body (61) in this way, the contact angle between the valve body (61) and the refrigerant oil is increased compared to when the second coating (612) is not formed.

[0065] In this second embodiment, it is preferable to set the contact angle of the valve body (61) with the refrigerant oil to be greater than or equal to the minimum contact angle of the valve retainer (65) with the refrigerant oil shown in Figures 7 and 8.

[0066] Since the other components are the same as in Embodiment 1, the same reference numerals are used for the same components and their detailed descriptions are omitted.

[0067] (Embodiment 3) Figure 11A is a diagram corresponding to Figure 5A of Embodiment 3. In Embodiment 3, as shown in Figures 11B and 12, a first coating (652) is formed on the valve retainer (65), and a second coating (612) is formed on the surface of the valve body body (611) of the valve body on the valve retainer (65) side, similar to Embodiment 2.

[0068] Since the other components are the same as in Embodiment 1, the same reference numerals are used for the same components and their detailed descriptions are omitted.

[0069] In embodiments 1 and 3 described above, the first coating (652) was formed only on the surface of the valve retainer (65) on the valve body (61) side, but it may also be formed on the entire surface. In this case, the first coating (652) can be easily formed by immersing the entire valve retainer (65) in the coating agent.

[0070] Furthermore, in embodiments 2 and 3 described above, the second coating (612) was formed only on the surface of the valve body (61) on the valve retainer (65) side, but it may also be formed on the entire surface. In this case, the second coating (612) can be easily formed by immersing the entire valve body (61) in the coating agent.

[0071] While embodiments have been described above, it will be understood that various modifications to the form and details are possible without departing from the spirit and scope of the claims. Furthermore, the above embodiments and modifications may be combined or substituted as appropriate, as long as they do not impair the functions covered by this disclosure. [Industrial applicability]

[0072] This disclosure is useful as a compressor having a valve body for opening and closing a discharge port for releasing fluid from a compression chamber, and a valve retainer that contacts the valve body from the side opposite the discharge port when the discharge port is open. [Explanation of Symbols]

[0073] 10 Compressor 31 Front head (partition member) 36 Compression Chamber 38. Piston (rotating component) 50 outlet 61 Valve body 65 Valve retainer 612 Second coating 652 1st coating

Claims

1. A partition member (31) has a discharge port (50) for discharging fluid from the compression chamber (36) and separates the inside and outside of the compression chamber (36), A valve body (61) that opens and closes the discharge port (50), A valve retainer (65) that contacts the valve body (61) from the side opposite the discharge port when the discharge port (50) is open, A compressor having a rotating member (38) that rotates to compress the fluid drawn into the compression chamber (36), A coating (652) is formed on the surface of the valve retainer (65) on the valve body (61) side, and the contact angle with the refrigeration oil is larger compared to when the coating (652) is not formed. A compressor characterized in that the maximum rotational speed of the rotating member (38) is 118 rpm or more, and the contact angle between the surface of the valve retainer (65) on the valve body (61) side and the refrigerant oil is 45 deg or more.

2. In the compressor according to claim 1, A compressor characterized in that the maximum rotational speed of the rotating member (38) is 130 rpm or more, and the contact angle between the surface of the valve retainer (65) on the valve body (61) side and the refrigerant oil is 49 degrees or more.

3. In the compressor according to claim 2, A compressor characterized in that the maximum rotational speed of the rotating member (38) is 150 rpm, and the contact angle between the surface of the valve retainer (65) on the valve body (61) side and the refrigerant oil is 60 deg or more.

4. In the compressor according to any one of claims 1 to 3, The compressor is characterized in that the coating (652) is made of PTFE resin, PFA resin, FEP resin, or ETFE resin.

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