WO2018168590A1

WO2018168590A1 - Thermal expansion valve

Info

Publication number: WO2018168590A1
Application number: PCT/JP2018/008670
Authority: WO
Inventors: 宏已太田
Original assignee: 株式会社デンソー
Priority date: 2017-03-17
Filing date: 2018-03-07
Publication date: 2018-09-20
Also published as: JP2018155309A; JP6828532B2

Abstract

A thermal expansion valve applied to a vapor-compression refrigeration cycle device and having a first body part (51), a second body part (52), a valve body part (53), an element part (54), and a securing member (55). A constriction passage (50a) for reducing the pressure of a high-pressure refrigerant is formed in the first body part. A low-pressure refrigerant passage (50c) through which a low-pressure refrigerant passes is formed in the second body part. The valve body part is housed in the first body part, and changes the passage cross-sectional area of the constriction passage. The element part displaces the valve body part. The securing member secures the first body part and the element part to each other. The element part displaces the valve body part in accordance with the temperature and the pressure of the low-pressure refrigerant passing through the low-pressure refrigerant passage. The second body part is formed of a resin having a lower thermal conductivity than the first body part and the securing member. The second body part is arranged between the element part and the first body part. At least a portion of the securing member is arranged inside the low-pressure refrigerant passage.

Description

Thermal expansion valve

Cross-reference of related applications

This application is based on Japanese Patent Application No. 2017-052052 filed on March 17, 2017, the contents of which are incorporated herein by reference.

The present disclosure relates to a temperature type expansion valve applied to a refrigeration cycle apparatus.

Conventionally, a box-type temperature expansion valve is known as a refrigerant pressure reducing device applied to a vapor compression refrigeration cycle apparatus.

This type of thermal expansion valve includes a body part, a valve body part, an element part, and the like. The body portion forms an outer shell of the temperature type expansion valve and forms a plurality of refrigerant passages and the like therein. The valve body portion is housed inside the body portion, and changes the passage cross-sectional area (that is, the throttle opening) of the throttle passage formed in the body portion. The element part is fixed to the body part and displaces the valve body part.

More specifically, the element portion has a diaphragm that deforms according to the temperature and pressure of the low-pressure refrigerant that flows through the low-pressure refrigerant passage formed in the body portion. Then, the deformation of the diaphragm is transmitted to the valve body part via an operating rod or the like, thereby displacing the valve body part. Therefore, in order to accurately adjust the throttle opening according to the temperature and pressure of the low-pressure refrigerant, it is necessary to appropriately transmit the temperature and pressure of the low-pressure refrigerant to the element portion.

On the other hand, Patent Document 1 discloses a temperature type expansion valve including a body portion formed of a resin having a lower thermal conductivity than metal. In the temperature type expansion valve of this patent document 1, by adopting a resin body part, the atmospheric temperature is prevented from being transmitted to the element part through the body part, and the temperature of the low-pressure refrigerant is supplied to the element part. Is trying to communicate properly.

JP 11-325308 A

However, when a body part formed of resin is employed as in the temperature type expansion valve of Patent Document 1, a dimensional change may occur in the body part due to deterioration over time such as creep. Such a dimensional change may cause a change in the shape of the throttle passage, a change in the relative position between the throttle passage and the element portion, and the like, and may change the flow characteristics of the temperature type expansion valve.

That is, if a body portion made of resin is used to adjust the throttle opening with high accuracy, the durability as a temperature type expansion valve may be deteriorated.

In view of the above points, it is an object of the present disclosure to provide a temperature type expansion valve capable of adjusting the throttle opening with high accuracy without causing deterioration of durability.

A temperature type expansion valve according to an aspect of the present disclosure is applied to a vapor compression refrigeration cycle apparatus, and includes a first body part, a second body part, a valve body part, an element part, and a fixing member. . The first body part is formed with a throttle passage for depressurizing the high-pressure refrigerant. In the second body part, a low-pressure refrigerant passage for circulating the low-pressure refrigerant is formed. The valve body portion is accommodated in the first body portion and changes the passage cross-sectional area of the throttle passage. The element part displaces the valve body part. The fixing member fixes the first body part and the element part to each other. The element portion displaces the valve body portion according to the temperature and pressure of the low-pressure refrigerant flowing through the low-pressure refrigerant passage. The first body part and the fixing member are made of metal. The second body part is formed of a resin having a lower heat transfer coefficient than the first body part and the fixing member. The second body part is disposed between the element part and the first body part. At least a part of the fixing member is disposed in the low-pressure refrigerant passage.

According to this, since the first body portion and the fixing member are made of metal, the shape of the throttle passage changes due to aging, and the relative position between the throttle passage and the element portion changes. This can be suppressed. Therefore, deterioration of the durability of the temperature type expansion valve can be suppressed.

Furthermore, since the second body part in which the low-pressure refrigerant passage is formed is formed of resin, the outside air temperature may be transmitted to the low-pressure refrigerant flowing through the low-pressure refrigerant passage, and the second body part may be externally connected via the second body part. It can suppress that temperature is transmitted to an element part.

In addition, since at least a part of the fixing member is disposed in the low-pressure refrigerant passage, at least a part of the fixing member can be brought close to the temperature of the low-pressure refrigerant. Therefore, it can suppress that external temperature will be transmitted to an element part via a 1st body part and a fixing member.

As a result, the throttle opening degree of the throttle passage can be adjusted with high accuracy according to the temperature and pressure of the low-pressure refrigerant.

That is, according to this one aspect, it is possible to provide a temperature type expansion valve capable of accurately adjusting the throttle opening without causing deterioration in durability.

It is a sectional view of a temperature type expansion valve concerning at least one embodiment of this indication. FIG. 2 is a partial cross-sectional view taken along a line II-II in FIG. It is an external appearance perspective view of a vibration-proof spring. It is a sectional view of a temperature type expansion valve concerning at least one embodiment of this indication. It is sectional drawing of the temperature type expansion valve of the modification of 2nd Embodiment.

Hereinafter, a plurality of modes for carrying out the present disclosure will be described with reference to the drawings. In each embodiment, parts corresponding to the matters described in the preceding embodiment may be denoted by the same reference numerals, and redundant description may be omitted. When only a part of the configuration is described in each mode, the other modes described above can be applied to the other parts of the configuration. Not only combinations of parts that clearly show that combinations are possible in each embodiment, but also combinations of the embodiments even if they are not explicitly stated unless there is a problem with the combination. Is also possible.

(First embodiment)
Hereinafter, a first embodiment of the present disclosure will be described with reference to the drawings. In this embodiment, the temperature type expansion valve 5 according to the present disclosure is applied to a vapor compression refrigeration cycle apparatus 1 used in an air conditioner. As shown in FIG. 1, the refrigeration cycle apparatus 1 is configured by connecting a compressor 2, a radiator 3, a receiver 4, a temperature expansion valve 5, and an evaporator 6 in an annular shape.

The compressor 2 sucks the refrigerant and compresses and discharges the refrigerant until it becomes a high-pressure refrigerant. The radiator 3 is a heat exchanger for radiating heat to exchange heat between the high-pressure refrigerant discharged from the compressor 2 and the outside air, and to dissipate and condense the high-pressure refrigerant. The receiver 4 is a liquid receiver that separates the gas-liquid refrigerant flowing out of the radiator 3 and stores excess liquid refrigerant in the cycle.

The temperature type expansion valve 5 is a decompression device that decompresses the high-pressure refrigerant flowing out from the receiver 4 until it becomes a low-pressure refrigerant. The evaporator 6 exchanges heat between the low-pressure refrigerant decompressed by the temperature type expansion valve 5 and the blown air blown into the air-conditioning target space, evaporates the low-pressure liquid refrigerant and exerts an endothermic effect. It is an exchanger.

The refrigeration cycle apparatus 1 employs an HFC-based refrigerant (specifically, R134a) as the refrigerant, and a vapor compression subcriticality in which the pressure of the refrigerant discharged from the compressor 2 does not exceed the refrigerant critical pressure. It constitutes the refrigeration cycle. Refrigerating machine oil for lubricating the compressor 2 is mixed in the refrigerant, and a part of the refrigerating machine oil circulates in the cycle together with the refrigerant.

Next, the detailed configuration of the temperature type expansion valve 5 of the present embodiment will be described. The temperature type expansion valve 5 includes a first body part 51, a second body part 52, a valve body part 53, an element part 54, and the like. The temperature-type expansion valve 5 is formed as a so-called box-type temperature-type expansion valve in which a low-pressure refrigerant passage 50c for detecting the temperature and pressure of the low-pressure refrigerant is formed.

The first body portion 51 and the second body portion 52 form an outer shell of the temperature type expansion valve 5 and form a plurality of refrigerant passages and the like therein. The first body portion 51 is formed of a prismatic metal (in this embodiment, aluminum). The first body portion 51 forms a throttle passage 50a, a valve chamber 50b, and the like inside.

The throttle passage 50a is a refrigerant passage that functions as an orifice for reducing the pressure of the high-pressure refrigerant flowing out of the receiver 4 until it becomes a low-pressure refrigerant by reducing the cross-sectional area of the refrigerant passage. The throttle passage 50a is formed in a rotating body shape such as a columnar shape or a truncated cone shape.

The valve chamber 50b is a space that is disposed on the refrigerant flow upstream side of the throttle passage 50a and accommodates the valve body 53. The valve chamber 50b is formed in a cylindrical shape having a diameter larger than that of the throttle passage 50a. The central axis of the throttle passage 50a and the central axis of the valve chamber 50b are arranged coaxially.

The valve body 53 is a spherical valve that changes the passage cross-sectional area of the throttle passage 50a by being displaced in the central axis direction of the throttle passage 50a. The valve chamber 50b accommodates a coil spring 53a that is an elastic member that applies a load on the valve body portion 53 that reduces the passage cross-sectional area of the throttle passage 50a.

On the outer surface of the first body portion 51, there are opened a high-pressure side inlet 51a through which the high-pressure refrigerant flowing out from the receiver 4 flows into the valve chamber 50b, and an evaporator-side outlet 51b through which the low-pressure refrigerant decompressed in the throttle passage 50a flows out. is doing. Further, the first body portion 51 is formed with an accommodation hole 51c for accommodating the valve body portion 53 and the coil spring 53a in the valve chamber 50b. The accommodation hole 51c is closed by an adjustment screw 53b that adjusts the load of the coil spring 53a.

A seal member such as an O-ring is disposed between the first body portion 51 and the adjustment screw 53b, so that the refrigerant does not leak from the gap between the first body portion 51 and the adjustment screw 53b.

The second body portion 52 is formed of a prismatic resin (in this embodiment, PPS: polyphenylene sulfide resin). Therefore, the second body part 52 is formed of a member having a lower heat transfer coefficient than that of the first body part 51. The second body portion 52 forms a low-pressure refrigerant passage 50c and the like inside.

The second body part 52 is arranged so as to contact the first body part 51. A seal member such as an O-ring is disposed between the first body part 51 and the second body part 52, and the refrigerant does not leak from the gap between the first body part 51 and the second body part 52. .

The low-pressure refrigerant passage 50c is a refrigerant passage through which the low-pressure refrigerant that has flowed out of the evaporator 6 flows. The low-pressure refrigerant passage 50c is formed in a cylindrical shape. As shown in FIGS. 1 and 2, the central axis of the low-pressure refrigerant passage 50c and the central axis of the throttle passage 50a are arranged so as to be orthogonal to each other.

On the outer surface of the second body 52, the low-pressure side inlet 52a through which the low-pressure refrigerant that has flowed out of the evaporator 6 flows into the low-pressure refrigerant passage 50c, and the low-pressure refrigerant that has circulated through the low-pressure refrigerant passage 50c to the suction side of the compressor 2. A compressor side outlet 52b to be discharged is opened. Further, the second body portion 52 is formed with a mounting hole 52c into which a part of the element portion 54 is fitted.

The element portion 54 outputs a driving force for displacing the valve body portion 53. The element portion 54 includes a case 54a, a diaphragm 54b, and the like. The case 54a is formed of a bowl-shaped (cup-shaped) metal (in this embodiment, a stainless alloy). The case 54a has an enclosed space 541 and an introduction space 542 formed therein.

The enclosed space 541 is a space in which a temperature-sensitive medium that changes in pressure according to the temperature of the low-pressure refrigerant flowing through the low-pressure refrigerant passage 50c is enclosed. In the present embodiment, the temperature-sensitive medium is mainly composed of a refrigerant circulating in the cycle. The introduction space 542 is a space for introducing the pressure of the low-pressure refrigerant flowing through the low-pressure refrigerant passage 50c.

The diaphragm 54b is disposed inside the case 54a, and divides the inside of the case 54a into an enclosed space 541 and an introduction space 542. In other words, the diaphragm 54b forms an enclosed space 541 together with the case 54a.

The diaphragm 54b is formed of a circular thin plate-like metal (SUS304 in this embodiment), and deforms according to the pressure difference between the pressure of the temperature-sensitive medium in the enclosed space 541 and the refrigerant pressure in the introduction space 542. . As described above, since the pressure of the temperature-sensitive medium changes according to the temperature of the low-pressure refrigerant flowing through the low-pressure refrigerant passage 50c, the diaphragm 54b is deformed according to the temperature and pressure of the low-pressure refrigerant flowing through the low-pressure refrigerant passage 50c. It is a deformation member to do.

The operating rod 54c is connected to the surface of the diaphragm 54b on the introduction space 542 side via a disk-shaped plate member. The actuating rod 54c is formed of a cylindrical metal (in this embodiment, a stainless alloy). The operating rod 54c transmits the deformation of the diaphragm 54b to the valve body 53 and displaces the valve body 53.

The operating rod 54c is supported by a vibration-proof spring 54d so as to be slidable in the direction of the central axis of the throttle passage 50a. The anti-vibration spring 54d is formed by bending a plate-like metal (in this embodiment, a stainless alloy) into a cylindrical shape. As shown in FIG. 3, the vibration-proof spring 54d has an annular portion 54e and a plurality of (three in this embodiment) arm portions 54f.

The annular portion 54e can elastically change the outer diameter, and is fixed to the first body portion 51 by means such as press fitting. Further, the vibration-proof spring 54d of the present embodiment is fixed to the first body portion 51 so that the center axis of the vibration-proof spring 54d and the center axis of the throttle passage 50a are arranged coaxially.

The arm portion 54f is formed by bending the cut and raised portion formed in the annular portion 54e toward the inner peripheral side (that is, the central axis side). The arm portions 54f are arranged at equiangular intervals when viewed from the central axis direction. Then, when the operating rod 54c is inserted into the center portion of the vibration-proof spring 54d, the distal end portion of each arm portion 54f comes into contact with the outer peripheral surface of the operating rod 54c.

Thus, when the operating rods 54c come into contact with the respective arm portions 54f, the displacement of the operating rods 54c in the central axis radial direction is restricted. As a result, the operating rod 54c is supported so as to be slidable in the central axis direction of the throttle passage 50a.

Further, the vibration isolating spring 54d slides between the arm portion 54f and the operating rod 54c when the valve body 53 is also displaced in the central axis direction of the throttle passage 50a in accordance with the displacement of the operating rod 54c in the central axis direction. Thus, a load is generated in a direction to suppress the displacement. Due to this load, it is possible to suppress the valve body portion 53 from vibrating minutely in the axial direction.

Further, a thread portion is formed at a portion of the element portion 54 that forms the introduction space 542 side of the case 54a. The screw portion is screwed to a fixing member 55 connected to the first body portion 51. Thereby, the element part 54 and the 1st body part 51 are being fixed mutually. The fixing member 55 of this embodiment is formed integrally with the first body portion 51. Therefore, the fixing member 55 is formed of the same type of metal as the first body portion 51.

The fixing member 55 is formed in a cylindrical shape. The fixing member 55 is disposed around the operating rod 54c so as to accommodate the operating rod 54c therein. Further, as shown in FIGS. 1 and 2, the fixing member 55 is disposed so as to penetrate the low-pressure refrigerant passage 50c. In other words, at least a part of the fixing member 55 is disposed in the low-pressure refrigerant passage 50c.

The outer peripheral surface of the fixing member 55 is formed with a plurality of pressure equalizing holes 55a (in this embodiment, four at equal angular intervals) that communicate the inside and the outside. Inside the fixed member 55, a communication passage 55b is formed for guiding the low-pressure refrigerant flowing in through the pressure equalizing hole 55a to the introduction space 542 side of the element portion 54. Thereby, the low-pressure refrigerant flowing through the low-pressure refrigerant passage 50 c is guided to the introduction space 542.

Then, the temperature of the low-pressure refrigerant guided to the introduction space 542 is transmitted to the temperature-sensitive medium in the enclosed space 541 through the diaphragm 54b.

Furthermore, the element portion 54 comes into contact with the second body portion 52 by being fixed to the fixing member 55. For this reason, the second body portion 52 is disposed so as to be sandwiched between the element portion 54 and the first body portion 51. A seal member such as an O-ring is disposed between the element portion 54 and the second body portion 52, and the refrigerant does not leak from the gap between the element portion 54 and the second body portion 52.

Next, the manufacturing method of the temperature type expansion valve 5 of this embodiment is demonstrated. First, the first body part 51, the second body part 52, the valve body part 53, and the element part 54 described above are prepared. At this time, the first body portion 51 is prepared in which the fixing member 55 is fixed or integrated. In addition, an element portion 54 to which an operating rod 54c is connected is prepared.

Next, the valve body 53, the coil spring 53a and the like are accommodated in the valve chamber 50b of the first body 51. Then, the accommodation screw 51c of the 1st body part 51 is obstruct | occluded by screwing the adjustment screw 53b (valve body part accommodation process).

Next, the fixing member 55 is fitted into the second body portion 52 so that the fixing member 55 connected to the first body portion 51 passes through the low-pressure refrigerant passage 50c of the second body portion 52 (second body). Part mounting process).

Next, the operating rod 54 c of the element portion 54 is inserted into the fixing member 55. Then, the case 54 a of the element portion 54 is screwed to a screw portion formed at the distal end portion of the fixing member 55. At this time, a part of the case 54a of the element portion 54 is screwed so as to be fitted into the attachment hole 52c of the second body portion 52 (element portion attachment step).

Thereby, not only the first body part 51 and the element part 54 are fixed to each other, but also the second body part 52 is sandwiched between the first body part 51 and the element part 54. Therefore, the first body part 51, the second body part 52, and the element part 54 are fixed to each other. Thereafter, the load applied by the coil spring 53a to the valve body 53 is adjusted to an appropriate value by the adjusting screw 53b (load adjusting step). Thereby, the temperature type expansion valve 5 is manufactured.

Next, the operation of this embodiment will be described. When the compressor 2 is operated, the high-pressure refrigerant compressed by the compressor 2 flows into the radiator 3. In the radiator 3, the high-pressure refrigerant dissipates heat to the outside air and condenses. The high-pressure liquid phase refrigerant condensed in the radiator 3 flows into the high-pressure side inlet 51 a of the temperature type expansion valve 5 through the receiver 4. At this time, excess liquid refrigerant in the cycle is stored in the receiver 4.

In the temperature type expansion valve 5, the element portion 54 displaces the valve body portion 53 so that the superheat degree of the refrigerant on the outlet side of the evaporator 6 becomes a predetermined reference superheat degree (5 ° C. in the present embodiment), The passage sectional area of the throttle passage 50a (that is, the throttle opening) is changed.

More specifically, when the temperature (superheat degree) of the refrigerant flowing through the low-pressure refrigerant passage 50c rises as the superheat degree of the refrigerant on the outlet side of the evaporator 6 rises, the pressure equalizing hole 55a and the communication passage 55b of the fixing member 55 are increased. As a result, the temperature of the refrigerant flowing into the introduction space 542 rises. As a result, the pressure of the temperature sensitive medium in the enclosed space 541 increases.

For this reason, when the degree of superheat of the refrigerant on the outlet side of the evaporator 6 increases, the diaphragm 54b is deformed to expand the enclosing space 541. When the operating rod 54c is displaced along with this deformation, the valve body 53 is displaced to the side away from the inlet of the throttle passage 50a. In other words, the valve body 53 is displaced to the side that increases the throttle opening of the throttle passage 50a.

On the other hand, when the temperature (superheat degree) of the refrigerant flowing through the low-pressure refrigerant passage 50c is reduced as the superheat degree of the refrigerant on the outlet side of the evaporator 6 is reduced, the pressure equalizing hole 55a of the fixing member 55 and the communication passage 55b are used. The temperature of the refrigerant flowing into the introduction space 542 decreases. Thereby, the pressure of the temperature-sensitive medium in the enclosed space 541 decreases.

For this reason, when the degree of superheat of the refrigerant on the outlet side of the evaporator 6 is lowered, the diaphragm 54b is deformed to a side for reducing the enclosed space 541. When the operating rod 54c is displaced along with this deformation, the valve body 53 is displaced toward the inlet of the throttle passage 50a due to the load of the coil spring 53a. In other words, the valve body 53 is displaced toward the side where the throttle opening of the throttle passage 50a is decreased.

That is, in the temperature type expansion valve 5, the valve body 53 can be displaced according to the temperature and pressure of the refrigerant flowing out of the evaporator 6. Therefore, in the temperature type expansion valve 5 of the present embodiment, the valve body 53 is displaced so that the superheat degree of the refrigerant flowing out of the evaporator 6 approaches the reference superheat degree. The reference superheat degree can be changed by adjusting the load of the coil spring 53a with the adjusting screw 53b.

The low-pressure refrigerant decompressed by the temperature type expansion valve 5 flows out of the evaporator side outlet 51b of the temperature type expansion valve 5 and flows into the evaporator 6. The low-pressure refrigerant that has flowed into the evaporator 6 absorbs heat from the blown air and evaporates. Thereby, blowing air is cooled. The refrigerant that has flowed out of the evaporator 6 flows into the low-pressure refrigerant passage 50 c from the low-pressure side inlet 52 a of the temperature type expansion valve 5. The refrigerant flowing through the low-pressure refrigerant passage 50c flows out of the compressor side outlet 52b, is sucked into the compressor 2, and is compressed again.

The refrigeration cycle apparatus 1 of the present embodiment operates as described above and can cool the blown air. Under the present circumstances, according to the temperature type expansion valve 5 of this embodiment, the superheat degree of the evaporator 6 exit side refrigerant | coolant can be adjusted to an appropriate value. Thus, the refrigerant can be sufficiently evaporated by the evaporator 6 to improve the coefficient of performance (COP) of the cycle, and the occurrence of liquid compression of the compressor 2 can be suppressed.

Here, in order to accurately adjust the throttle opening degree of the temperature type expansion valve 5 according to the temperature and pressure of the low-pressure refrigerant flowing out of the evaporator 6, the temperature-sensitive medium in the enclosed space 541 of the element portion 54 is used. It is necessary to appropriately transmit the temperature and pressure of the low-pressure refrigerant that has flowed out of the evaporator 6.

Therefore, for example, it is conceivable to form the first body portion 51 and the second body portion 52 with a resin having a lower thermal conductivity than metal. The reason is that by forming both the first body part 51 and the second body part 52 with resin, the outside air temperature is transmitted to the temperature sensitive medium via the first body part 51 and the second body part 52. It is because it can suppress.

However, if both the first body portion 51 and the second body portion 52 are formed of resin, a dimensional change occurs in the first body portion 51 and the second body portion 52 due to deterioration over time such as creep. There is. Such a dimensional change changes the flow rate characteristic of the temperature type expansion valve 5 and causes the durability of the temperature type expansion valve 5 to deteriorate.

On the other hand, according to the temperature type expansion valve 5 of the present embodiment, since the first body portion 51 and the fixing member 55 are made of metal, the shape of the throttle passage 50a changes due to deterioration over time. In addition, it is possible to suppress the relative position between the throttle passage 50a and the element portion 54 from changing. Therefore, deterioration of the durability of the temperature type expansion valve 5 can be suppressed.

Furthermore, in the temperature type expansion valve 5 of the present embodiment, since the second body portion 52 in which the low-pressure refrigerant passage 50c is formed is formed of resin, the outside air temperature is transmitted to the low-pressure refrigerant flowing through the low-pressure refrigerant passage 50c. It is possible to prevent the outside air temperature from being transmitted to the temperature-sensitive medium of the element portion 54 via the second body portion 52.

In addition, since at least a part of the fixing member 55 is disposed in the low-pressure refrigerant passage 50c, at least a part of the fixing member 55 can be brought close to the temperature of the low-pressure refrigerant flowing through the low-pressure refrigerant passage 50c. .

More specifically, at least a part of the transmission path for transmitting the outside air temperature from the first body part 51 to the element part 54 via the fixing member 55 can be brought close to the temperature of the low-pressure refrigerant flowing through the low-pressure refrigerant passage 50c. . Therefore, it is possible to suppress the outside air temperature from being transmitted to the temperature sensitive medium of the element portion 54 through the first body portion 51 and the fixing member 55.

As a result, according to the temperature type expansion valve 5 of the present embodiment, the throttle opening can be accurately adjusted according to the temperature and pressure of the refrigerant flowing out from the evaporator 6 without deteriorating durability. .

Further, in the temperature type expansion valve 5 of the present embodiment, the low pressure refrigerant passage 50c through which the low temperature low pressure refrigerant flows is formed in the second body portion 52 formed of resin. For this reason, the temperature rise of the 2nd body part 52 is few, and the heat resistance requested | required of the 2nd body part 52 also becomes low. Therefore, the second body portion 52 can be formed of a resin material that is relatively inexpensive and easy to process.

Further, in the temperature type expansion valve 5 of the present embodiment, the second body portion 52 is disposed between the first body portion 51 and the element portion 54. Therefore, by fixing the first body part 51 and the element part 54 via the fixing member 55, the second body part 52 can be sandwiched, and the second body part 52 can be easily fixed.

Moreover, in the temperature type expansion valve 5 of this embodiment, the cylindrical fixing member 55 is employ | adopted and arrange | positioned at the outer peripheral side of the action | operation rod 54c. Therefore, even if the fixing member 55 is provided, the size of the temperature expansion valve 5 as a whole is not increased. Furthermore, the fixing member 55 can be easily disposed so as to penetrate the low-pressure refrigerant passage 50c.

In the present embodiment, the pressure equalizing hole 55 a is formed on the cylindrical side surface of the fixing member 55, and the communication path 55 b is formed inside the fixing member 55. Therefore, the refrigerant pressure and the refrigerant temperature in the introduction space 542 can be quickly changed. Then, the temperature of the low-pressure refrigerant can be quickly transmitted to the temperature-sensitive medium in the enclosed space 541. As a result, the throttle opening can be adjusted with higher accuracy.

(Second Embodiment)
This embodiment demonstrates the example which changed the fixing member 55 and the 2nd body part 52 as shown in FIG. 4 with respect to 1st Embodiment. In FIG. 4, the same or equivalent parts as those in the first embodiment are denoted by the same reference numerals. The same applies to the following drawings.

The fixing member 55 of the present embodiment is formed as a separate member with respect to the first body portion 51. The fixing member 55 of this embodiment is formed of the same type of metal as the first body portion 51. In the fixing member 55 of the present embodiment, the end portion on the opposite side of the element portion 54 is screwed to the first body portion 51.

Further, the vibration isolating spring 54d of the present embodiment is disposed in the communication path 55b of the fixing member 55. In the second body portion 52 of the present embodiment, the low pressure refrigerant passage 50c, the low pressure side inlet 52a, and the compressor side outlet 52b are different in inner diameter from the first embodiment (small in this embodiment). Adopted.

Other configurations and operations are the same as those in the second embodiment. Therefore, also in the temperature type expansion valve 5 of the present embodiment, the throttle opening can be accurately adjusted according to the temperature and pressure of the refrigerant flowing out of the evaporator 6 without deteriorating durability.

Further, in the present embodiment, since the anti-vibration spring 54d is disposed in the communication path 55b, the space in the communication path 55b can be used effectively. Furthermore, as shown in FIG. 5, a plurality of vibration-proof springs 54d (two in the modification shown in FIG. 5) may be arranged in the communication path 55b. According to this, the coaxiality between the central axis of the throttle passage 50a and the central axis of the operating rod 54c can be improved, and the throttle opening can be adjusted with higher accuracy.

In the present embodiment, since the second body portion 52 is changed, the inner diameters of the low pressure side inlet 52a and the compressor side outlet 52b are changed without changing the first body portion 51, the element portion 54, and the like. be able to. That is, in the temperature type expansion valve 5, since the first body part 51 and the second body part 52 are formed as separate members, by changing either one of them, it is applied to a wide refrigeration cycle apparatus having different pipe diameters. be able to.

Furthermore, since the low-pressure refrigerant passage 50c of the present embodiment is formed in a columnar shape, the inflow direction of the refrigerant flowing into the low-pressure side inlet 52a (that is, the axial direction of the opening hole forming the low-pressure side inlet 52a) and the compressor The outflow direction of the refrigerant flowing out from the side outlet 52b (that is, the axial direction of the opening hole forming the compressor side outlet 52b) coincides.

On the other hand, by forming the low-pressure refrigerant passage 50c into a curved shape, the inflow direction of the refrigerant flowing into the low-pressure side inlet 52a and the outflow direction of the refrigerant flowing out from the compressor-side outlet 52b are made different directions. Can do. Therefore, the temperature type expansion valve 5 can be applied to a wide range of refrigeration cycle apparatuses having different pipe mounting positions.

The present disclosure is not limited to the above-described embodiment, and various modifications can be made as follows without departing from the spirit of the present disclosure.

In the above-described embodiment, the example in which R134a is employed as the refrigerant has been described as the refrigerant of the refrigeration cycle apparatus, but the refrigerant is not limited to this. For example, R1234yf, R600a, R410A, R404A, R32, R407C, etc. may be adopted. Or you may employ | adopt the mixed refrigerant | coolant etc. which mixed multiple types among these refrigerant | coolants.

Therefore, the main component of the temperature sensitive medium is not limited to R134a. For example, a mixture of a plurality of types of refrigerants may be employed as the temperature sensitive medium, or a refrigerant obtained by adding an inert gas such as helium or nitrogen to the refrigerant may be employed.

In the above-described embodiment, an example of the manufacturing method of the temperature type expansion valve 5 has been described. However, the first body portion 51 and the second body portion are performed by performing the element portion attaching step after the second body portion attaching step. 52 and the element portion 54 can be easily fixed. Therefore, the order of the steps is not limited to the order disclosed in the above-described embodiment. For example, the valve body housing step may be executed after the element portion mounting step.

In the second embodiment described above, the example in which the fixing member 55 and the first body portion 51 are fixed by screw fastening has been described, but the fixing mode between the fixing member 55 and the first body portion 51 is not limited to this. For example, the fixing member 55 may be fixed to the first body portion 51 by press fitting, or may be fixed using a joining means such as adhesion or welding.

The application of the temperature type expansion valve 5 according to the present disclosure is not limited to the refrigeration cycle apparatus 1 disclosed in the above embodiment.

For example, the present invention may be applied to a refrigeration cycle apparatus that constitutes a so-called gas injection cycle in which an intermediate-pressure refrigerant is merged with a refrigerant in a pressure increasing process by a compressor. In this case, for example, it may be used as a high-stage decompression device that decompresses the high-pressure refrigerant until it becomes an intermediate-pressure refrigerant, or as a low-stage decompression device that decompresses the intermediate-pressure refrigerant until it becomes a low-pressure refrigerant. .

Further, the present invention may be applied to a refrigeration cycle apparatus that constitutes a so-called ejector refrigeration cycle that includes an ejector as a refrigerant decompression apparatus. In this case, for example, the refrigerant that flows into the nozzle portion of the ejector may be used as an intermediate pressure reducing device that reduces the pressure until it becomes an intermediate pressure refrigerant.

Although the present disclosure has been described based on the embodiments, it is understood that the present disclosure is not limited to the embodiments and structures. The present disclosure includes various modifications and modifications within the equivalent range. In addition, although various combinations and forms are shown in the present disclosure, other combinations and forms including only one element, more or less than them are also included in the scope and concept of the present disclosure. Is.

Claims

A temperature type expansion valve applied to a vapor compression refrigeration cycle apparatus,
A first body part (51) formed with a throttle passage (50a) for depressurizing the high-pressure refrigerant;
A second body part (52) formed with a low-pressure refrigerant passage (50c) for circulating the low-pressure refrigerant;
A valve body portion (53) accommodated in the first body portion and changing a cross-sectional area of the throttle passage;
An element part (54) for displacing the valve body part;
A fixing member (55) for fixing the first body part and the element part to each other;
The element portion displaces the valve body portion according to the temperature and pressure of the low-pressure refrigerant flowing through the low-pressure refrigerant passage,
The first body part and the fixing member are made of metal,
The second body part is formed of a resin having a lower heat transfer coefficient than the first body part and the fixing member,
The second body part is disposed between the element part and the first body part,
A temperature type expansion valve in which at least a part of the fixing member is disposed in the low-pressure refrigerant passage.
The element portion includes a deformable member (54b) that deforms according to the temperature and pressure of the low-pressure refrigerant that flows through the low-pressure refrigerant passage, and a columnar operating rod (54c) that transmits deformation of the deformable member to the valve body portion. Have
The temperature type expansion valve according to claim 1, wherein the fixing member is formed in a cylindrical shape and disposed around the operating rod.
A pressure equalizing hole (55a) for communicating the inside and the outside is formed on the outer peripheral surface of the fixing member,
The temperature type expansion valve according to claim 2, wherein a communication path (55b) for guiding the low-pressure refrigerant to the element part side is formed inside the fixing member.