JP2008101881A - Pressure control valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pressure control valve capable of preventing that a refrigerant temperature can not be accurately detected because of mounting attitude and a controlled pressure of high pressure is fluctuated when a temperature of the refrigerant flowing into a temperature sensitive portion becomes lower than a critical temperature, with a simple structure. <P>SOLUTION: A sealed space T including the refrigerant is divided by a diaphragm 13, and a through hole 19 is formed on the diaphragm 13, so that the liquid refrigerant existing in a space 12d of a valve element 12 can be reserved in a space by a position of the through hole 19 when a space inner wall is a bottom, even when an expansion valve 7 is transversely disposed, thus the outflow of the refrigerant into a back space A can be prevented. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a pressure control valve for a vapor compression refrigeration cycle. For example, the present invention relates to a pressure control valve that controls the refrigerant pressure on the gas cooler outlet side based on the refrigerant temperature between the gas cooler outlet side and the evaporator inlet side.

For example, in a vehicle air conditioner, a vapor compression refrigeration that circulates CO ₂ as a refrigerant as a refrigeration cycle including a compressor (compressor), a gas cooler (heat radiator), a pressure control valve, an evaporator (evaporator), an accumulator, and the like. There is a cycle. As a pressure control valve used in such a vapor compression refrigeration cycle, the following is proposed.

JP-A-5-26541 JP-A-8-193769 JP 2006-220407 A

The pressure control valve for the CO ₂ refrigeration cycle needs to be placed in the engine room to detect the refrigerant temperature at the gas cooler outlet and control the high pressure, and the pressure control valve used for the conventional HFC refrigerant is placed in the passenger compartment Compared to what has been used, it is used in an environment where the ambient temperature is high.

As an expansion valve for the CO ₂ refrigeration cycle, the above-mentioned Patent Document 3 proposes a configuration in which a temperature sensing part having a diaphragm built in is disposed on the end face of the body. Because it is installed, it is exposed to the engine room atmosphere.

When CO ₂ is used as the refrigerant, the temperature-sensitive portion of the pressure control valve changes in pressure according to the temperature, and for example, the same CO ₂ as that of the refrigerant is enclosed as a medium for displacing the displacement portion.
CO ₂ has a critical refrigerant temperature of approximately 30 ° C., and no liquid refrigerant is generated above the critical temperature. However, below the critical temperature, the temperature-sensitive portion is gas-liquid, as is the case with an expansion valve used for a conventional HFC refrigerant. A liquid refrigerant is generated in a two-phase state. On the other hand, the members constituting the temperature sensing part of the pressure control valve include a member that faces the high-pressure refrigerant or high-pressure refrigerant passage to be detected and easily reflects the temperature of the high-pressure refrigerant, and a member that is directly exposed to the outside air, for example. There are members that do not easily reflect the refrigerant temperature. Here, since the liquid refrigerant flows downward due to gravity and tends to accumulate under the sealed space in the temperature sensing unit, the liquid refrigerant may accumulate in an undesired position depending on the posture of the pressure control valve. For example, when the diaphragm that easily reflects the temperature of the high-pressure refrigerant is not positioned on the lower side, such as when the pressure control valve is disposed sideways, the liquid refrigerant may contact a wall surface having a higher temperature than the high-pressure refrigerant. Therefore, there arises a problem that the control pressure shifts.

However, in the pressure control valve for the HFC-based refrigerant, the above-mentioned Patent Document 1 proposes a method of attaching an adsorbent to the diaphragm, or Patent Document 2 proposes adding a liquid reservoir structure to the diaphragm. Joining a part to a diaphragm that is displaced by the peeling of the agent or pressure causes a problem that it is difficult to process the diaphragm, and the durability is affected when the displacement state changes.
The present invention has been proposed to improve such a problem, and an object thereof is to suppress fluctuations in control characteristics due to the mounting posture of the pressure control valve.
Another object of the present invention is to suppress fluctuations in control characteristics even when the mounting posture of the pressure control valve changes over a wide range.
Another object of the present invention is to suppress fluctuations in control characteristics depending on the mounting posture of the pressure control valve with a simple configuration.
Furthermore, in the pressure control valve used in a supercritical cycle, particularly in a cycle using CO ₂ as a refrigerant, the present invention is caused by the mounting posture when the refrigerant temperature flowing into the temperature sensing part becomes lower than the critical temperature. It is an object of the present invention to provide a pressure control valve that can prevent a refrigerant temperature from being accurately detected and prevent a high-pressure control pressure from shifting with a simple structure.

  In order to solve the above-described problem, in claim 1, a temperature sensing space configured as a part of the sealed space T in the valve body 12 for adjusting the passage opening degree of the refrigerant flow path from the high pressure side to the low pressure side of the refrigeration cycle. In 12d, the liquid reservoir that stores and holds the liquefied medium among the medium sealed in the sealed space T is configured, so that the liquefied medium can be stored and held in the liquid reservoir regardless of the mounting posture. It is possible to prevent the control pressure from shifting.

  Further, in claim 2, the temperature sensing space 12d in the valve body 12 extends along the displacement direction of the displacement member 13, and communicates with the remaining sealed space T through the end opening. Thus, movement between the temperature-sensitive space 12d of the medium and the remaining sealed space T is enabled, and the operation of the displacement member 13 is not hindered.

  According to a third aspect of the present invention, the liquid reservoir is provided with an embankment that holds the liquefied medium even in a state where at least the installation posture of the pressure control valve is directed sideways, so that the pressure is maintained in the state directed sideways. Even if a control valve is installed, it is possible to prevent the liquefied medium from flowing out of the liquid reservoir.

  According to a fourth aspect of the present invention, the liquefied medium can be held by the levee portion by projecting the levee portion toward the radially inner side from the wall surface defining the temperature sensitive space 12d.

  Further, in claim 5, the temperature sensitive space 12d is formed in a columnar shape, and the levee portion is configured to extend annularly along the circumferential direction of the temperature sensitive space 12d. It can be held in the temperature sensitive space 12d.

  Further, in claim 6, the displacement member 13 is a diaphragm having a through hole 19 smaller than the inner diameter of the temperature sensitive space 12d, and the valve body 12 positions the temperature sensitive space 12d and the through hole 19 coaxially, Since the periphery of the through hole 19 of the displacement member 13 is a bank portion, the liquefied medium in the temperature sensitive space 12d does not flow out by the periphery of the through hole 19 of the displacement member 13 and flows out of the temperature sensitive space 12d. Can be held in.

  According to the seventh aspect of the present invention, the levee portion is configured by at least one annular plate 21 disposed in the temperature-sensitive space 12d, so that the liquefied medium in the temperature-sensitive space 12d flows out by the annular plate 21. Without being held in the temperature sensitive space 12d.

  According to the eighth aspect of the present invention, the levee portion is configured by the annular plate 22 disposed at the end opening of the temperature sensitive space 12d, so that the liquefied medium in the temperature sensitive space 12d does not flow out by the annular plate 22. It can be held in the temperature sensitive space 12d.

  According to the ninth aspect of the present invention, the dyke portion is constituted by the pipe member 23 extending from the opening portion into the temperature-sensitive space 12d. For example, even if the pressure control valve is reversed and attached, The liquefied medium can be held between the temperature sensitive space 12d and the pipe member 23 without flowing out.

  Further, in claim 10, the displacement member 13 is a diaphragm having a through hole 19, and the valve body 12 positions the temperature sensitive space 12d and the through hole 19 on the same axis, and the levee portion and the valve body. Since the displacement member 13 is positioned between the dam 12 and the levee portion, partial deformation of the displacement member 13 can be suppressed.

  Further, in claim 11, the levee portion is formed such that the diameter of the end opening of the valve body 12 is smaller than the diameter of the bottom portion, so that the liquefied medium in the temperature sensitive space 12d by the levee portion is It can be held without spilling.

  In the twelfth aspect of the present invention, the diameter of the through hole 19 is set to ½ or less of the inner diameter of the temperature sensing space 12d in the valve body 12, for example, even if the pressure control valve is installed sideways, the temperature sensing space 12d. An amount of the liquefied medium that is assumed to be generated at a temperature lower than the critical temperature can be retained in the space from the inner wall to the bottom of the through hole 19.

  Further, in claim 13, the volume surrounded by the surface including the axis passing through the through hole 19 of the temperature sensing space 12 d in the valve body 12 is set to 18% or more of the total volume of the sealed space T. An amount of the liquefied medium assumed to be generated at a temperature lower than the temperature can be retained.

  Further, according to the fourteenth aspect, the outer diameter of the pipe member 23 is 1/2 or less of the inner diameter of the space 12d in the valve body 12, so that even if the pressure control valve is installed upside down, it becomes the critical temperature or lower. The amount of liquefied medium expected to be generated can be retained.

  Further, in claim 15, the volume of the space surrounded by the inner wall of the sealed space T, the liquid refrigerant movement prevention wall, and the outer wall of the pipe member 23 is 18% or more of the total volume of the sealed space T, so An amount of the liquefied medium assumed to be generated at a temperature lower than the temperature can be retained.

Hereinafter, an embodiment of a pressure control valve according to the present invention will be described and described with reference to the accompanying drawings.
FIG. 1 shows an example of a vapor compression refrigeration cycle 1 using a pressure control valve according to the present invention to circulate carbon dioxide (CO ₂ ) as a refrigerant. In the refrigeration cycle 1, the refrigerant is pressurized to the supercritical pressure on the high pressure side, so it is also called a supercritical refrigeration cycle. The pressure control valve can also function to decompress and expand the refrigerant from the high pressure side to the low pressure side. In this embodiment, the pressure control valve is referred to as a pressure reducer or an expansion valve. Therefore, the pressure control valve will be described below as an expansion valve.
That is, in this vapor compression refrigeration cycle 1, reference numeral 2 is a compressor (compressor) for sucking and compressing refrigerant (CO ₂ ), and reference numeral 3 is a gas cooler (heat radiator) for cooling the refrigerant compressed by the compressor 2. is there. An internal heat exchanger 4 is arranged on the outlet side of the gas cooler 3. A temperature sensing cylinder 5 is installed at the outlet side pipe of the gas cooler 3, and is connected to the expansion valve 7 by a capillary tube 6. Therefore, the valve opening degree of the expansion valve 7 is controlled by the change in the internal pressure based on the refrigerant temperature of the medium sealed in the temperature sensing cylinder 5. The expansion valve 7 also functions as a decompressor that decompresses the high-pressure refrigerant.

The medium enclosed in the temperature sensitive cylinder 5 is selected according to the required control characteristics. For example, as a medium, (1) refrigerant, (2) CO ₂ (carbon dioxide), (3) a plurality of mixed media (for example, a mixed medium of a refrigerant and one or a plurality of media), (4) normal use In the range, a gas that is not condensed and liquefied can be mixed with the refrigerant (for example, a mixed medium of an inert gas such as nitrogen and the refrigerant).

  The temperature sensing cylinder 5 can be arranged so as to sense the refrigerant temperature between the gas cooler 3 and the evaporator 8 inlet. In one alternative form, the temperature sensing cylinder 5 can be arranged at the outlet of the internal heat exchanger 4 as one of the high-pressure refrigerant paths downstream from the gas cooler 3. In this embodiment, a temperature sensing part is provided by a displacement mechanism as a pressure-position converting mechanism provided in the expansion valve 7, the temperature sensing cylinder 5, and the capillary tube 6. In this embodiment, the temperature sensing unit is provided integrally with the expansion valve 7.

In the vapor compression refrigeration cycle 1, reference numeral 8 is an evaporator that evaporates the gas-liquid two-phase refrigerant decompressed by the expansion valve 7, and reference numeral 9 separates the gas-phase refrigerant and the liquid-phase refrigerant and This is an accumulator that temporarily stores excess refrigerant.
And the internal heat exchanger 4 is arrange | positioned in a cycle so that the refrigerant | coolant which goes to the expansion valve 7 from the gas cooler 3 and the refrigerant | coolant which returns to the compressor 2 from the accumulator 9 may heat-exchange. Therefore, the expansion valve 7 is disposed in the refrigerant passage from the internal heat exchanger 4 to the evaporator 8.

Next, FIG. 2 shows the expansion valve 7 according to the first embodiment used in the vapor compression refrigeration cycle 1, and will be described in detail below.
The expansion valve 7 has a body 10 having a substantially rectangular parallelepiped shape. In the body 10 of the expansion valve 7, a first flow path D that is a part of the refrigerant flow path from the gas cooler 3 to the internal heat exchanger 4 and an internal heat exchanger are provided in the body 10 of the expansion valve 7. A second flow path E which is a part of the refrigerant flow path from 4 to the evaporator 8 via the valve port 10a is formed independently. The second flow path E has a high-pressure side passage and a low-pressure side passage that are slightly shifted. A valve port 10a is provided between the high-pressure side passage and the low-pressure side passage. The first flow path D and the second flow path E are provided so as to penetrate from one surface of the body 10 to the other surface. The first flow path D and the second flow path E are positioned substantially in parallel.
Further, the body 10 is formed with a first opening 10b for installing a temperature sensing section described later and a second opening 10c for setting the adjustment spring 11. A through hole is formed from the first opening 10b to the second opening 10c. The first opening 10b and the second opening 10c are formed along a direction intersecting the first flow path D and the second flow path E. A valve body 12 is accommodated in the body 10 so as to open and close the valve port 10a. The valve body 12 is a rod-shaped member, and has a temperature-sensitive portion located across the first flow path D and a movable valve body portion (described later) provided at the tip of the temperature-sensitive portion. As a result, the refrigerant flow path from the internal heat exchanger 4 to the evaporator 8 via the valve port 10a is switched to a communication state or a non-communication state. Furthermore, in this embodiment, the opening area and opening degree of the refrigerant flow path are adjusted.

  A temperature sensing unit is attached to the first opening 10 b of the body 10. The temperature sensing part is substantially composed of a valve body 12, a displacement member 13 (hereinafter referred to as a diaphragm 13), a lid body 14 and a lower support member 15, and a sealed space T is formed therein. A back space A as a part of the sealed space T is defined between the lid body 14 and the diaphragm 13. The back space A is a space for displacing the diaphragm 13 and is a space for securing the volume of the medium. A concave portion is formed in the central portion of the lid body 14 to ensure a required volume. The rear space A is defined by sandwiching and fixing the peripheral edge of the diaphragm 13 between the lid body 14 and the lower support member 15. The diaphragm 13 has a thin film shape made of a stainless material, and is deformed and displaced according to a pressure difference between the inside and outside of the sealed space T. The lower support member 15 has a screw portion formed on the outer periphery of the cylindrical portion 15a. The lower support member 15 is attached to the body 10 by screwing a screw portion into the first opening 10 b of the body 10. The lower support member 15 has an opening that communicates with the first flow path D in order to introduce the high-pressure refrigerant that is the detection target into the lower temperature-sensitive surface of the diaphragm 13. Further, the valve body 12 extends from the opening of the lower support member 15. An enclosure tube 16 is attached to the lid body 14, and a refrigerant is enclosed in the sealed space T from the enclosure tube 16. After the refrigerant is sealed, the sealing tube 16 is sealed.

  The valve body 12 has an opening on the diaphragm 13 side. The valve body 12 has a flange portion 12b that expands radially outward on the diaphragm 13 side. The flange portion 12b surrounds the opening. The valve body 12 is a rod-shaped member extending from the diaphragm 13 and has a valve portion 12a at the tip thereof. Inside the valve body 12, a cylindrical and bottomed temperature-sensitive space 12 d is formed as a part of the sealed space T at a portion extending from the center to the open end. In addition, the valve part 12a and the temperature sensitive space 12d can also be comprised separately. Inside the valve body 12, the temperature sensitive space 12 d extends upward from the valve portion 12 a across the first flow path D and through the inside of the cylindrical portion 15 a of the lower support member 15. One flange portion 12 b is fixed to the diaphragm 13. A gap B having an annular cross section is provided between the inner surface of the cylindrical portion 15 a and the outer peripheral surface of the valve body 12. The gap B communicates with the first flow path D connected to the gas cooler 3 outlet side. Therefore, the refrigerant on the outlet side of the gas cooler 3 flows into the gap B, and the refrigerant temperature is transmitted to the medium in the sealed space T. At the same time, the pressure of the refrigerant on the outlet side of the gas cooler 3 acts on the diaphragm 13.

  Furthermore, the valve body 12 has the other end part 12c extended through the valve opening 10 below the valve part 12a. An adjustment nut 17 is screwed to the end 12c. An adjustment spring 11 for biasing the valve element 12 in the valve closing direction is interposed between the periphery of the lower surface of the valve port 10 and the adjustment nut 17, and an initial set load (valve of the adjustment spring 11 is adjusted by turning the adjustment nut 17. The elastic force when the mouth 10 is closed can be arbitrarily adjusted. The adjustment spring 11 and the adjustment nut 17 are provided in the downstream space C connected to the inlet side of the evaporator 8. Further, the cap 18 is fitted into the second opening 10c of the body 10 so that the lower portion of the downstream space C is closed.

The diaphragm 13 is formed with a through hole 19 that allows the back space A and the temperature sensitive space 12d to communicate with each other. The through hole 19 is provided at the center of the diaphragm 13. The center of the through hole 19 is located coaxially with the central axis of the temperature sensitive space 12d.
The temperature sensitive space 12d extends from the end on the diaphragm 13 side toward the first flow path D as a high-pressure refrigerant path. The tip of the temperature sensitive space 12d reaches the valve body 12 that traverses the first flow path D. The temperature sensitive space 12d extends from a portion adjacent to the diaphragm 13 to a position reaching the first passage D. In this embodiment, the temperature sensing cylinder 5 and the capillary tube 6 are provided by the temperature sensing space 12 d and the through hole 19. The through hole 19 is a through hole provided through the diaphragm 13.
The flange portion 12 b of the valve body 12 is airtightly connected to the diaphragm 13 outside the through hole 19. The through hole 19 is a round hole. The diameter of the through hole 19 is smaller than the inner diameter of the temperature sensitive space 12d. The center of the through hole 19 substantially coincides with the central axis of the temperature sensitive space 12d. The inner edge of the diaphragm 13 positioned around the through-hole 19 covers the entire edge of the end opening on the diaphragm 13 side of the temperature-sensitive space 12d, and protrudes inward. As a result, the diaphragm 13 forms an eaves-like bank extending from the outside to the inside in the radial direction of the temperature-sensitive space 12d. Even when the expansion valve 7 is disposed so as to be inclined from the vertical direction illustrated in FIG. 2, the levee can store a liquid medium in the temperature-sensitive space 12 d.
In this embodiment, the total volume Vtotal of the sealed space T provided in the temperature sensing part is the volume Vback of the back space A adjacent to the diaphragm 13 and partitioned by the diaphragm 13, the volume V12d of the temperature sensing space 12d, It is the sum of the volume V16 of the internal space of the sealed tube 16. In this embodiment, the temperature of the high-pressure refrigerant flowing through the first flow path D is also transmitted to the refrigerant in the temperature sensitive space 12d. Since the medium in the temperature sensing space 12d communicates with the back space A through the through-hole 19, the pressure change in the temperature sensing space 12d changes the pressure in the sealed space T including the back space A, and the diaphragm 13 is displaced. Let As a result, the total volume of the sealed space of the temperature sensing part in which the refrigerant is enclosed can be expanded. With such a configuration, it is possible to increase the refrigerant temperature detection sensitivity and improve the refrigerant temperature detection accuracy.

  In the pressure control valve 7 configured as described above, since the diameter of the through hole 19 provided in the diaphragm 13 is smaller than the inner diameter of the temperature sensing space 12d in the valve body 12, the pressure control valve 7 is Even when mounted horizontally, it is possible to prevent the liquid refrigerant present in the temperature sensitive space 12d in the valve body 12 from flowing out into the back space A on the diaphragm 13 side as shown in FIG. In this embodiment, the displacement direction of the diaphragm 13 is set as the up-down direction, and the inner edge of the diaphragm 13 as a bank is provided so as to extend in a direction perpendicular to the displacement direction. Therefore, even if the posture of the expansion valve 7 is set so that the displacement direction of the diaphragm 13 is horizontal, the liquid refrigerant can be stored over the entire region in the longitudinal direction of the temperature sensitive space 12d. Furthermore, the inner edge of the diaphragm 13 as the bank portion has a sufficient height toward the radially inner side. For this reason, liquid refrigerant can be stored in the temperature sensitive space 12d even if the temperature sensing part is positioned somewhat below the posture in which the displacement direction of the diaphragm 13 is set to the horizontal direction.

  Thereby, since a liquid refrigerant accumulates in the temperature sensitive space 12d in the valve body 12 which contacts the refrigerant in a cycle, the fluctuation | variation of an operating pressure can be suppressed.

Further, since the expansion valve for HFC has a structure in which the valve portion is pushed down by the diaphragm, there is no need to fix the diaphragm and the valve body, whereas the expansion valve 7 for CO ₂ has the valve portion 12a by the diaphragm 13. Therefore, the diaphragm 13 and the valve body 12 need to be joined together.
For this reason, in the expansion valve 7 for CO ₂ , it is easy to provide a space serving as a temperature sensing portion in the valve body 12. According to the shape of this embodiment, the posture change allowable range of the expansion valve 7 can be adjusted by changing the diameter of the through hole 19 in the diaphragm 13. For example, by setting the diameter of the through hole 19 to be small, even if the expansion valve 7 is tilted 90 degrees or more from front to back and left and right from the posture shown in FIG. 2, the liquid refrigerant is accumulated to the vicinity of the bottom of the temperature sensitive space 12 d. Is possible.

Here, FIG. 4 shows the gas and liquid refrigerant density at 10 to 30 ° C. and the volume ratio of the liquid refrigerant at that time when the refrigerant is in a gas-liquid two-phase state.
According to the graph shown in FIG. 4, when the refrigerant temperature is 30 ° C., the volume ratio of the liquid refrigerant is the largest, and if the volume of the portion that holds the liquid refrigerant is approximately 18% or more of the total enclosed space, It can be seen that the entire amount of liquid refrigerant can be held, and the most effective is obtained.
In addition, as shown in FIG. 5, in order to make the volume (shaded part) of the part holding the liquid refrigerant approximately 18% or more of the total volume of the temperature sensing part, the communication hole diameter is set to 1 / of the temperature sensing part inner diameter. It may be 2 or less. In FIG. 5, the horizontal axis represents the ratio between the inner diameter of the hole 12d serving as the cylindrical temperature sensing portion and the diameter of the through hole 19 disposed on the end face thereof. FIG. 6 is a perspective view showing a storage state of the liquid refrigerant in the temperature sensing unit. The communication hole is provided coaxially with the central axis of the cylindrical temperature sensing part. Even in a state where the valve shaft of the expansion valve 7 is positioned in the horizontal direction, the liquid refrigerant is stored in the temperature sensing portion.

The expansion valve according to the present invention can also be configured as follows. In this embodiment, components having substantially the same configuration as the above-described expansion valve 7 are denoted by the same reference numerals.
In the expansion valve 7 according to the second embodiment, as shown in FIG. 7, a reinforcing member 20 that prevents partial deformation of the diaphragm 13 is disposed at a portion where the valve body 12 and the diaphragm 13 are joined. In addition, a through hole 20a that communicates the back space A and the temperature sensitive space 12d is provided. A through hole 19 is provided in the diaphragm 13. The through hole 19 is formed to be approximately equal to or larger than the inner diameter of the temperature-sensitive space 12d, and does not function as a bank portion for retaining the liquid refrigerant. In this embodiment, the diameter of the through hole 20a is set so that the inner edge portion of the reinforcing member 20 functions as a bank portion.
In this case, the reinforcing member 20 is at the center of the diaphragm 13 and the through hole 20a is provided at the center. According to the shape of this embodiment, the liquid refrigerant is stored in the temperature sensitive space 12d even if the posture of the expansion valve 7 is tilted from the illustrated posture to the front, rear, left and right by 90 °. Further, the liquid refrigerant is stored in the temperature sensitive space 12d even if it slightly exceeds 90 °.
In the present embodiment, an inert gas (nitrogen or the like) is sealed in addition to the refrigerant (CO ₂ ) in a sealed space that is a temperature sensing unit. The inert gas imparts an initial load to the diaphragm 13. With this configuration, the spring for applying the initial load can be reduced, or the adjustment spring can be eliminated as in this embodiment.

  Also with such an expansion valve 7, liquid refrigerant can be stored in the temperature sensitive space 12d.

Moreover, the pressure control valve concerning this invention can also be comprised as follows.
In the expansion valve 7 of the third embodiment, as shown in FIG. 8, an annular plate 21 that prevents liquid refrigerant from flowing out is disposed in a space 12 d in the valve body 12. That is, a plurality of annular plates 21 are arranged in the space 12 d in the valve body 12 so as to partition the space 12 d at predetermined intervals, and through holes 21 h are formed in each of the annular plates 21. One or more annular plates 21 are provided. The annular plate 21 is press-fitted, for example, so that the outer edge thereof is in close contact with the inner wall surface of the valve body 12. The diaphragm 13 is provided with a through hole that is sufficiently larger than the inner diameter of the temperature sensitive space 12d. The annular plate 21 has a function as a bank portion. The flange 12 b on the diaphragm 13 side of the valve body 12 is positioned so as to penetrate the through hole of the diaphragm 13. Therefore, the diaphragm 13 does not have a function as a bank portion.

  Even in such an expansion valve 7, even when the expansion valve 7 is mounted sideways, as shown in FIG. 9, the liquid refrigerant existing in the space 12d in the valve body 12 passes through the space 12d at predetermined intervals. It is stored in the temperature sensitive space 12d by the partitioning annular plate 21. In this embodiment, even if the posture of the expansion valve 7 is tilted by 90 ° to the front, rear, left and right from the posture in which the diaphragm 13 is positioned on the upper side, the liquid refrigerant is stored in the temperature sensitive space 12d. Further, the liquid refrigerant is stored in the temperature sensitive space 12d even if it slightly exceeds 90 °. In addition, since the annular plate 21 is provided deep inside the temperature sensitive space 12d, the liquid refrigerant can be stored at the bottom of the temperature sensitive space 12d.

Moreover, the pressure control valve concerning this invention can also be comprised as follows.
In the expansion valve 7 of the fourth embodiment, as shown in FIG. 10, an annular plate 22 for preventing the liquid refrigerant from flowing out is provided at the center of the diaphragm 13 so as to face the back space A side. One end of the pipe member 23 is attached to the annular plate 22. The pipe member 23 extends concentrically in the space 12d in the valve body 12. In this embodiment, the dam part is constituted by the annular plate 22 and the pipe member 23. The temperature sensing space 12 d in the valve body 12 has a longitudinal direction along the displacement direction of the diaphragm 13. In this embodiment, the bank portion is formed in a cylindrical shape. The cylindrical dyke portion is liquid-tightly joined to the opening portion of the diaphragm 13 at one end thereof. The tubular bank portion extends toward the inside of the temperature sensitive space 12d, and the other end opens near the bottom of the temperature sensitive space 12d. The tubular bank portion is positioned so as to partition an annular gap between the inner wall of the valve body 12 that partitions the temperature sensitive space 12d. The annular gap provides a predetermined volume capable of storing a necessary liquid refrigerant. In this embodiment, the liquid reservoir part in which the liquid refrigerant is stored can be formed in the temperature sensitive space 12d. Moreover, this liquid reservoir can store the liquid refrigerant even when the diaphragm 13 is positioned on the lower side.

  According to such an expansion valve 7, even when the mounting posture is reversed, as shown in FIG. 11, the liquid refrigerant is separated from the outer periphery of the pipe member 23, the inner wall 12 d of the valve body 12, the annular plate 22, and the like. Can be prevented from flowing out to the back space A side.

Furthermore, the expansion valve according to the present invention can be configured as follows as a fifth embodiment.
The expansion valve 7 according to the fifth embodiment transmits the outlet refrigerant temperature of the high-pressure side internal heat exchanger 4 to the temperature sensing part to achieve high-pressure control, and is used in the vapor compression refrigeration cycle 1 shown in FIG. It is done. Note that, in the vapor compression refrigeration cycle 1, the same reference numerals are given to components that are substantially the same as the components of the vapor compression refrigeration cycle 1 shown in FIG.
The vapor compression refrigeration cycle 1 here is different from the vapor compression refrigeration cycle 1 shown in FIG. 1 in that the temperature sensing cylinder 5 and the capillary tube 6 connected to the outlet pipe of the gas cooler 3 are omitted. The expansion valve 7 according to the embodiment is connected to the outlet side of the internal heat exchanger 4 connected to the outlet side of the gas cooler 3.

In the expansion valve 7, in the valve body 12 that is provided in the body 10 and switches the second flow path E from the internal heat exchanger 4 to the evaporator 8, a flange portion that couples the valve body 12 and the diaphragm 13 to the temperature sensing space 12d. A throttle portion 12V having an inner diameter narrowing toward 12b is formed, and a through hole 19 is provided in the diaphragm 13 for communicating the back space A and the temperature sensitive space 12d.
The throttle portion 12V is formed coaxially with the temperature sensitive space 12d and has a smaller diameter than the inner diameter of the temperature sensitive space 12d.

  In such an expansion valve 7 as well, the throttle portion 12V functions as a bank portion, and liquid refrigerant is stored in the temperature-sensitive space 12d even when the posture of the expansion valve 7 is tilted 90 ° from front to back and left and right from the illustrated posture. Is done.

As mentioned above, although various embodiment was mentioned and demonstrated about the pressure control valve concerning this invention, of course, this invention is not limited to these embodiment.
That is, in the above-described embodiment, the annular plate 22 is used as the liquid refrigerant movement prevention wall. However, as long as the temperature prevention part can be provided with a movement prevention wall, other shapes can of course have the same effect. Can play.

It is system | strain explanatory drawing which shows an example of the vapor compression refrigeration cycle which has an internal heat exchanger using the pressure control valve concerning this invention. It is sectional drawing which shows an example of the pressure control valve concerning this invention used for the vapor compression refrigeration cycle shown in FIG. It is sectional drawing for demonstrating an effect | action when the pressure control valve shown in FIG. 2 is installed sideways. It is a graph which shows the volume ratio of the liquid refrigerant | coolant at that time and the gas and liquid refrigerant density in 10-30 degreeC with which a refrigerant | coolant will be a gas-liquid two-phase state of the pressure control valve shown in FIG. FIG. 2 shows the relationship between the volume ratio of the portion capable of holding the liquid refrigerant with respect to the diameter of the through hole and the inner diameter of the temperature sensing portion of the pressure control valve shown in FIG. 2 and the volume ratio of the portion capable of holding the liquid refrigerant with respect to the total volume of the temperature sensing portion. It is a graph. It is a perspective view which shows the storage state of the liquid refrigerant in the temperature sensing part of the pressure control valve shown in FIG. It is sectional drawing which shows another example of the pressure control valve concerning this invention used for the vapor compression refrigeration cycle shown in FIG. It is sectional drawing which shows another example of the pressure control valve concerning this invention used for the vapor compression refrigeration cycle shown in FIG. It is sectional drawing for demonstrating an effect | action at the time of installing the pressure control valve shown in FIG. 8 sideways. It is sectional drawing which shows another example of the pressure control valve concerning this invention used for the vapor compression refrigeration cycle shown in FIG. It is sectional drawing for demonstrating an effect | action at the time of inverting and installing the pressure control valve shown in FIG. It is a system | strain explanatory drawing which shows the other example of the vapor compression refrigeration cycle which has an internal heat exchanger using the expansion valve concerning this invention. It is sectional drawing which shows an example of the expansion valve concerning this invention used for the vapor compression refrigeration cycle shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vapor compression refrigeration cycle 2 Compressor 3 Gas cooler 4 Internal heat exchanger 5 Temperature sensing tube 6 Capillary tube 7 Pressure control valve 8 Evaporator 9 Accumulator 10 Body 10a Valve port 10b First opening 10c Second opening 11 Adjustment spring 12 Valve body 12a Valve portion 12b End portion 12d Space 12v Restriction portion 13 Diaphragm 14 Lid 15 Lower support member 15a Cylindrical portion 16 Enclosed tube 17 Adjustment nut 18 Cap 19 Through hole 20 Reinforcing member 20a Through hole 21 Annular plate 21h Through hole 22 Annular plate 23 Pipe member

Claims (15)

A valve body (12) for adjusting the passage opening degree of the refrigerant flow path from the high pressure side to the low pressure side of the refrigeration cycle and a displacement member (13) for driving the valve body (12) are accommodated and enclosed with a medium. A pressure control valve that forms a sealed space (T) in which the pressure changes according to the high-pressure side refrigerant temperature, and that forms a temperature-sensitive space (12d) as a part of the sealed space (T) in the valve body (12). In
A pressure control valve characterized in that a liquid reservoir for storing and holding a liquefied medium among the medium sealed in the sealed space (T) is formed in the temperature sensitive space (12d).   The temperature sensing space (12d) in the valve body (12) extends along the displacement direction of the displacement member (13) and communicates with the remaining sealed space (T) through the end opening. The pressure control valve according to claim 1, wherein   2. The pressure control valve according to claim 1, wherein the liquid reservoir includes an embankment that holds the liquefied medium even at least in a state where the installation posture of the pressure control valve is directed sideways.   4. The pressure control valve according to claim 3, wherein the bank portion protrudes radially inward from a wall surface defining the temperature sensitive space (12 d).   The pressure control valve according to claim 3, wherein the temperature sensing space (12d) has a cylindrical shape, and the bank portion extends in an annular shape along a circumferential direction of the temperature sensing space (12d). The displacement member (13) is a diaphragm having a through hole (19) smaller than the inner diameter of the temperature sensitive space (12d),
The valve body (12) is disposed with the temperature sensing space (12d) and the through hole (19) positioned coaxially,
The pressure control valve according to claim 4, wherein the periphery of the through hole (19) of the displacement member (13) is configured as a bank portion.   The pressure control valve according to claim 6, wherein the levee portion is constituted by at least one annular plate (21) disposed in the temperature sensitive space (12d).   The pressure control valve according to claim 6, wherein the dyke portion is constituted by an annular plate (22) arranged at an end opening of the temperature sensitive space (12d).   The pressure control valve according to claim 8, wherein the bank portion is constituted by a pipe member (23) extending from the opening portion into the temperature sensitive space (12d). The displacement member (13) is a diaphragm having a through hole (19),
The valve body (12) is disposed with the temperature sensing space (12d) and the through hole (19) positioned coaxially,
The pressure control valve according to claim 8 or 9, wherein the displacement member (13) is positioned between the bank portion and the valve body (12).   The pressure control valve according to claim 5, wherein the levee portion is formed such that the diameter of the end opening of the valve body (12) is smaller than the diameter of the bottom portion.   The pressure control valve according to claim 6 or 10, wherein the diameter of the through hole (19) is ½ or less of the inner diameter of the temperature sensing space (12d) in the valve body (12).   The volume surrounded by the surface including the axis passing through the through hole (19) of the temperature sensing space (12d) in the valve body (12) is 18% or more of the total volume of the sealed space (T). 13. The pressure control valve according to claim 7 or 12, wherein:   The pressure control valve according to claim 9, wherein an outer diameter of the pipe member (23) is 1/2 or less of an inner diameter of a space (12d) in the valve body (12).   The volume of the space surrounded by the inner wall of the sealed space (T), the liquid refrigerant movement prevention wall, and the outer wall of the pipe member (23) is 18% or more of the total volume of the sealed space (T). The pressure control valve according to claim 9 or 14.

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