Valve device and air conditioner

Abstract

To provide an art which enables improvement of design pressure of a valve device.SOLUTION: A valve device 6 for opening and closing a passage of a refrigerant between a pipe 801 at the outside and a pipe 802 at the outside, includes: a valve housing 60 forming a valve internal passage 600; a valve seat 62 fixed to the valve housing 60 and formed with a valve port 620 serving as an inlet / outlet of the valve internal passage 600; and a valve rod 61 which is disposed within the valve housing 60, contacts with the valve seat 62 from the inner side of the valve housing 60 in a manner that the valve rod 61 closes the valve port 620 to close the valve internal passage 600 and separates from the valve seat 62 to open the valve internal passage 600. The valve housing 60 is provided with: a charge port 609 formed with a supply passage 602 for supplying the refrigerant from the outside to the inside of the valve internal passage 600; and a seal part protruding into the valve internal passage 600. The valve rod 61 contacts with the seal part of the valve housing 60 to block movement of the refrigerant between the pipes 801, 802 and the supply passage 602.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a valve device technology that can be used with high-pressure refrigerants. [Background technology]

[0002] Air conditioners achieve heating and cooling functions by forming a refrigeration cycle in which a refrigerant sealed in a sealed flow path transports heat. Such air conditioners have traditionally been equipped with a valve device that opens and closes the refrigerant flow path. Patent Document 1 describes a valve device that includes a valve body (valve housing), a valve stem, and a valve seat. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-169335 Summary of the Invention [Problem to be solved by the invention]

[0004] Recently, with increasing environmental awareness, there has been a demand for carbon dioxide as a refrigerant in air conditioners. When carbon dioxide is used as a refrigerant, a valve device that can withstand higher pressures is required compared to when conventional refrigerants are used.

[0005] However, the technology described in Patent Document 1 has a problem in that when the refrigerant pressure increases, the seal portion of the charge port cannot withstand the increased pressure.

[0006] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a technique for improving the design pressure of a valve device. [Means for solving the problem]

[0007] In order to solve the above problem, the invention of claim 1 is a valve device that opens and closes a refrigerant flow path between an external first pipe and an external second pipe, comprising: a valve housing that forms an intra-valve flow path; a valve seat that is fixed to the valve housing and has a valve orifice that serves as an inlet and outlet for the intra-valve flow path; and a valve stem that is disposed inside the valve housing and abuts against the valve seat from inside the valve housing to block the valve orifice, thereby closing the intra-valve flow path, and that opens the intra-valve flow path by moving away from the valve seat. The valve housing comprises a charge port that has a supply flow path formed therein for supplying the refrigerant from the outside into the intra-valve flow path, and a seal portion that protrudes into the intra-valve flow path, and the valve stem abuts against the seal portion of the valve housing to block the movement of the refrigerant between the first pipe and the second pipe and the supply flow path.

[0008] The invention of claim 2 is the valve device according to the invention of claim 1, wherein the valve housing is integrally molded.

[0009] The invention of claim 3 is the valve device according to the invention of claim 1, wherein the valve seat is fixed to the valve housing at an outer periphery of the valve port.

[0010] The invention of claim 4 is the valve device according to the invention of claim 1, wherein the valve housing includes a press-fit portion into which the valve seat is press-fitted.

[0011] The invention of claim 5 is a valve device according to the invention of claim 1, wherein the valve seat is provided with a first piping fixing portion that fixes the first piping while being fixed to the valve housing, thereby connecting the first piping to the in-valve flow path.

[0012] Furthermore, the invention of claim 6 is a valve device according to the invention of claim 1, wherein the valve housing is provided with a second piping fixing portion that fixes the second piping and connects the second piping to the in-valve flow path.

[0013] The invention of claim 7 is an air conditioning system comprising first and second pipes that form a refrigerant flow path, and a valve device that opens and closes the refrigerant flow path between the first and second pipes. The valve device comprises a valve housing that forms an intra-valve flow path, a valve seat fixed to the valve housing and formed with a valve orifice that serves as an inlet and outlet for the intra-valve flow path, and a valve stem that is disposed inside the valve housing and abuts against the valve seat from inside the valve housing to block the valve orifice, thereby closing the intra-valve flow path, and that opens the intra-valve flow path by moving away from the valve seat. The valve housing comprises a charge port that forms a supply flow path for supplying the refrigerant from the outside into the intra-valve flow path, and a seal portion that protrudes into the intra-valve flow path, and the valve stem abuts against the seal portion of the valve housing to block the movement of the refrigerant between the first and second pipes and the supply flow path. [Effects of the Invention]

[0014] According to the inventions of claims 1 to 7, the valve device comprises a valve housing forming an internal valve flow path, a valve seat fixed to the valve housing and formed with a valve port serving as an inlet and outlet for the internal valve flow path, and a valve stem disposed inside the valve housing that abuts against the valve seat from inside the valve housing to block the valve port, thereby closing the internal valve flow path, and that moves away from the valve seat to open the internal valve flow path. The valve housing also comprises a charge port formed with a supply flow path for supplying refrigerant from the outside into the internal valve flow path, and a seal portion protruding into the internal valve flow path. The valve stem abuts against the seal portion of the valve housing to block the movement of refrigerant between the first and second pipes and the supply flow path. This improves the sealing effect between the connected pipes and the outside. Therefore, the valve device can be used with refrigerants used at higher pressures than conventional devices. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 2 is a block diagram of an air conditioning device. [Figure 2] FIG. 2 is a schematic view showing a valve device. [Figure 3] FIG. 2 is a cross-sectional view showing a valve device. [Figure 4]FIG. 10 is a cross-sectional view showing a comparative example of a valve device. DETAILED DESCRIPTION OF THE INVENTION

[0016] Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, unless otherwise specified, in the following description, descriptions of directions and orientations correspond to the drawings for the convenience of the description, and do not limit, for example, the implementation, product, or scope of rights.

[0017] <1. Embodiment> FIG. 1 is a block diagram of an air conditioner 1. The air conditioner 1 includes an indoor unit 2 placed indoors and an outdoor unit 3 placed outdoors. The indoor unit 2 and the outdoor unit 3 are connected by pipes 80 and 81, which serve as indoor-outdoor communication pipes. As will be described in detail later, the air conditioner 1 forms a refrigeration cycle in which a refrigerant 90 circulates. Note that FIG. 1 shows a state in which pipes 80 and 86 are connected by four-way valve 8, and pipes 84 and 85 are connected.

[0018] The indoor unit 2 includes an indoor heat exchanger 20 and a fan 21. A pipe 80 and a pipe 81 are connected to the indoor heat exchanger 20. In this embodiment, the pipes 80 and 81 are made of copper.

[0019] In the state of the four-way valve 8 shown in FIG. 1, refrigerant 90 is supplied to the indoor heat exchanger 20 from the pipe 81, and the refrigerant 90 is discharged from the pipe 80. At this time, the refrigerant 90 that has flowed into the indoor heat exchanger 20 exchanges heat with the indoor air blown by the fan 21, evaporates, and is discharged as a low-temperature, low-pressure gas. That is, in the state shown in FIG. 1, the indoor heat exchanger 20 functions as an evaporator. Then, the indoor air that has exchanged heat with the refrigerant 90 absorbs heat from the refrigerant 90, is cooled, and is released into the room. Therefore, in the state of the four-way valve 8 shown in FIG. 1, the air conditioner 1 functions as an air conditioning system that cools the room.

[0020] On the other hand, when the four-way valve 8 is switched from the state shown in FIG. 1 , the pipes 80 and 84 are connected, and the pipes 85 and 86 are connected. In this state, high-temperature, high-pressure refrigerant 90 is supplied from the pipe 80 to the indoor heat exchanger 20, and the refrigerant 90 is discharged from the pipe 81. At this time, the high-temperature, high-pressure refrigerant 90 that has flowed into the indoor heat exchanger 20 exchanges heat with the indoor air blown by the fan 21, condenses, and is discharged as a high-temperature, high-pressure liquid. In other words, the indoor heat exchanger 20 functions as a condenser. The indoor air that has exchanged heat with the refrigerant 90 is then heated by radiating heat to the refrigerant 90 and released into the room. Therefore, at this time, the air conditioner 1 functions as a heating system that heats the room.

[0021] The outdoor unit 3 includes an outdoor heat exchanger 30, a fan 31, a housing 32, a compressor 4, a separator 5, a valve device 6, a four-way valve 8, and pipes 82, 83, 84, 85, and 86. The outdoor heat exchanger 30 is connected to a pipe 85 and a pipe 81.

[0022] 1, high-temperature, high-pressure refrigerant 90 is supplied to the outdoor heat exchanger 30 through pipe 85, and the refrigerant 90 is discharged through pipe 81. At this time, the refrigerant 90 that has flowed into the outdoor heat exchanger 30 exchanges heat with the outdoor air blown by the fan 31, condenses, and is discharged as a high-temperature, high-pressure liquid. In other words, when the air conditioner 1 functions as a cooling system, the outdoor heat exchanger 30 functions as a condenser. Note that the outdoor air that has exchanged heat with the refrigerant 90 releases heat from the refrigerant 90 and is discharged to the outside.

[0023] On the other hand, when the four-way valve 8 is switched from the state shown in FIG. 1 , refrigerant 90 is supplied to the outdoor heat exchanger 30 through the pipe 81, and the refrigerant 90 is discharged through the pipe 85. At this time, the refrigerant 90 that has flowed into the outdoor heat exchanger 30 exchanges heat with the outdoor air blown by the fan 31, evaporates, and is discharged as a low-temperature, low-pressure gas. In other words, when the air conditioner 1 functions as a heating system, the outdoor heat exchanger 30 functions as an evaporator. Then, the outdoor air that has exchanged heat with the refrigerant 90 absorbs heat from the refrigerant 90, is cooled, and is discharged outside.

[0024] The housing 32 is a member made by combining thin metal plates into a rectangular shape. The housing 32 has the function of housing and protecting the components of the outdoor unit 3. The housing 32 is not limited to being made of metal. For example, it may be made of resin, or multiple materials may be partially used and combined.

[0025] As shown in Fig. 1, the valve device 6 is attached to the housing 32. In other words, from the perspective of the valve device 6, the housing 32 can be said to be an external mounting member. Furthermore, the portion of the housing 32 to which the valve device 6 is attached is a plate-shaped portion. In other words, the housing 32 constitutes a mounting plate for the valve device 6.

[0026] Although not shown in detail, the valve device 6 is fixed by inserting bolts (not shown) into bolt holes that communicate between the outside and the inside of the outdoor unit 3 and fastening them with nuts (not shown). A cover for protecting the valve device 6 may also be attached to the housing 32.

[0027] The compressor 4 has a function of compressing the refrigerant 90 supplied from the pipe 82, changing it to a high-temperature, high-pressure state, and discharging it from the pipe 83. Conventionally, various structures and types of compressors 4 have been proposed, and the present invention can employ any of these as appropriate. That is, any device that has the function of changing the supplied refrigerant 90 to a high-temperature, high-pressure state and discharging it may be employed as the compressor 4 as appropriate.

[0028] Although detailed description will be omitted, the compressor 4 has sliding parts (for example, a cylinder, a piston, etc.) inside as a mechanism for compressing the refrigerant 90. As shown in Fig. 1, refrigeration oil 91 is stored (supplied) inside the compressor 4 as a lubricant for smooth sliding of the sliding parts.

[0029] The compressor 4 discharges the refrigerant 90 from the pipe 83 while maintaining a high temperature and pressure. At this time, refrigerating machine oil 91 is mixed with the discharged refrigerant 90 and is discharged from the compressor 4. This causes a shortage of refrigerating machine oil 91 in the compressor 4. Alternatively, it is conceivable that the discharged refrigerating machine oil 91 may adversely affect other components. Therefore, in the air conditioner 1, it is necessary to recover the refrigerating machine oil 91 discharged from the compressor 4 and return it to the compressor 4.

[0030] For example, the technology described in JP 2022-054728 A can be applied to the separator 5 provided in the air conditioner 1, so detailed description will be omitted below. However, the technology adopted by the separator 5 is not limited to the above technology.

[0031] The separator 5 has a function of separating refrigerating machine oil 91 from high-temperature, high-pressure refrigerant 90 flowing in from a pipe 83 and discharging the high-temperature, high-pressure refrigerant 90 from a pipe 84 .

[0032] The separator 5 removes the refrigerating machine oil 91, and the discharged high-temperature, high-pressure refrigerant 90 is guided by piping 84 toward the four-way valve 8. The refrigerant 90 discharged from the separator 5 is guided to the indoor heat exchanger 20 or the outdoor heat exchanger 30, depending on the state of the four-way valve 8. Of the indoor heat exchanger 20 and the outdoor heat exchanger 30, the one to which the refrigerant 90 discharged from the separator 5 is guided functions as a condenser in the refrigeration cycle.

[0033] On the other hand, the separated refrigerating machine oil 91 is discharged towards the compressor 4 via the pipe 82. In this way, in the air conditioner 1, the refrigerating machine oil 91 that has been discharged from the compressor 4 is recovered in the separator 5 and returned to the compressor 4.

[0034] As shown in Fig. 1, the separator 5 is connected to the four-way valve 8 via a pipe 86. A refrigerant 90 is guided to the pipe 86 from the indoor heat exchanger 20 or the outdoor heat exchanger 30 depending on the state of the four-way valve 8. Of the indoor heat exchanger 20 and the outdoor heat exchanger 30, the one connected to the pipe 86 by the four-way valve 8 functions as an evaporator in the refrigeration cycle. That is, the refrigerant 90 from the evaporator is supplied to the separator 5 via the pipe 86.

[0035] The refrigerant 90 supplied from the evaporator to the separator 5 via the pipe 86 is in a state where a gas component and a liquid component are mixed together. The liquid component of the refrigerant 90 introduced into the separator 5 falls by gravity and accumulates at the bottom of the separator 5. On the other hand, the gas component of the refrigerant 90 introduced into the separator 5 does not fall and accumulate at the bottom of the separator 5, but is discharged to the outside through the pipe 82.

[0036] In this way, separator 5 also has the function of separating gas refrigerant 90 from liquid refrigerant 90. However, the principle and method by which separator 5 separates gas and liquid components of refrigerant 90 are not limited to those exemplified here. For example, other methods employed in conventionally known gas-liquid separators may be employed as appropriate.

[0037] Fig. 2 is a schematic diagram showing the valve device 6. Note that the X-axis, Y-axis, and Z-axis in Fig. 2 are axes that are perpendicular to one another. In Fig. 2, two pipes 80 (forming a flow path for the refrigerant 90) connected to the valve device 6 from the outside are illustrated as pipes 801 and 802.

[0038] 2, the valve device 6 includes a valve housing 60, a cover nut 68, and a charge port nut 69. As will be described in detail later, the valve device 6 has a function of opening and closing the flow path of the refrigerant 90 between an external pipe 801 (first pipe) and an external pipe 802 (second pipe).

[0039] Valve housing 60 is formed with a substantially cylindrical central portion (not shown in FIG. 2) extending in the Z-axis direction, an attachment portion 606 protruding from the central portion in the (+Y) direction, and an attachment portion 607 protruding from the central portion in the (-Y) direction. Valve housing 60 also is formed with a second piping fixing portion 608 protruding from the central portion in the (+X) direction, and a charge port 609 protruding from the central portion in the (-X) direction.

[0040] The lid nut 68 is attached to an end portion protruding in the (+Z) direction from the central portion of the valve housing 60. The lid nut 68 will be described in further detail below.

[0041] The mounting portions 606 and 607 are parts of the valve housing 60 and are plate-like protruding portions that are approximately parallel to the XY plane. The mounting portions 606 and 607 have circular holes that penetrate the plate-like portions in the Z-axis direction.

[0042] The bolts (not shown) inserted into the circular holes of the mounting portions 606, 607 are also inserted into and communicate with holes that penetrate the housing 32, and are screwed into nuts (not shown) that are arranged opposite to them. In this way, the mounting portions 606, 607 have the function of fixing the valve device 6 to the housing 32 by the fastening force of the bolts and nuts described above.

[0043] The second pipe fixing portion 608 is a cylindrical portion that protrudes from the valve housing 60 in the (+X) direction. The inner diameter of the second pipe fixing portion 608 is designed to be smaller than the outer diameter of the second pipe 802. Therefore, when assembling the valve device 6, the end of the second pipe 802 can be inserted into the second pipe fixing portion 608 of the valve housing 60 while moving it in the (-X) direction. In other words, the second pipe fixing portion 608 forms a so-called boss. The outer surface of the second pipe 802 and the inner surface of the second pipe fixing portion 608 are integrally fixed by welding.

[0044] Charge port 609 is a cylindrical portion that protrudes in the (-X) direction from valve housing 60. Although not shown in detail, the outer surface of charge port 609 is threaded. This allows a charge port nut 69 to be attached to the (-X) side end of charge port 609. Charge port 609 will be described in more detail below.

[0045] Fig. 3 is a cross-sectional view of the valve device 6 taken along the line AA shown in Fig. 2. The valve device 6 further includes a valve stem 61 and a valve seat 62 in addition to the configuration shown in Fig. 2.

[0046] As already explained, the central portion of the valve housing 60 constitutes a substantially cylindrical portion along the Z-axis direction, and the internal space forms the intra-valve flow path 600, as shown in FIG.

[0047] In the valve housing 60, the second piping fixing part 608 protruding in the (+X) direction forms the in-valve flow path 601. The in-valve flow path 600 and the in-valve flow path 601 are connected in fluid communication within the valve housing 60, as shown in FIG. 3. As already explained, the pipe 802 is fixed to the second piping fixing part 608. As a result, the flow path of the refrigerant 90 formed by the pipe 802 is connected in fluid communication with the in-valve flow path 601.

[0048] In valve housing 60, the space inside charge port 609, which is a substantially cylindrical portion, forms supply flow path 602. As already explained, charge port nut 69 is attached to the (-X) side of charge port 609. Supply flow path 602 is sealed on the (-X) side by charge port nut 69. In other words, charge port nut 69 has the function of sealing charge port 609 (supply flow path 602) from the outside.

[0049] On the other hand, by removing charge port nut 69, which functions as a sealing member, from charge port 609, valve device 6 can open supply passage 602 to the outside. Therefore, by connecting a pipe (not shown) connected to a cylinder or the like that stores refrigerant 90 to charge port 609 while supply passage 602 is open, refrigerant 90 can be supplied into supply passage 602.

[0050] 3, the (+X) side end of the supply flow path 602 is connected to the in-valve flow path 600 inside the valve housing 60. Therefore, the refrigerant 90 supplied into the supply flow path 602 can move into the in-valve flow path 600. In this way, the charge port 609 is configured to supply the refrigerant 90 into the in-valve flow path 600.

[0051] The inner diameter of the valve housing 60 is larger on the (-Z) side than the position where the supply flow path 602 communicates with the in-valve flow path 600 (hereinafter sometimes referred to as the "supply position"), and the in-valve flow path 600 is wider. In other words, a step is provided within the in-valve flow path 600, which forms a seal portion 604 that protrudes into the in-valve flow path 600. As will be described in detail later, the seal portion 604 has the function of dividing the in-valve flow path 600 into two chambers, the (+Z) side and the (-Z) side, and controlling the movement of the refrigerant 90 in the in-valve flow path 600.

[0052] The end of the valve housing 60 in the (-Z) direction forms a valve seat fixing portion 605. The valve seat fixing portion 605 constitutes a substantially cylindrical portion, into which the substantially cylindrical valve seat 62 is fitted and fixed. In other words, the valve seat fixing portion 605 is a portion formed to fix the valve seat 62 to the valve housing 60.

[0053] The valve seat 62 is a member that is relatively small in size in the Z direction and can be press-fitted. Therefore, the (+Z) side portion of the valve seat fixing portion 605 forms a press-fit portion. As a result, the (+Z) side end of the valve seat 62 is press-fitted into the press-fit portion of the valve seat fixing portion 605 and fixed. Fixing the valve seat 62 by press-fitting in this way improves the positioning accuracy of the valve seat 62 in the XY plane. That is, the degree of coincidence between the axis S, which is the central axis of the valve stem 61, and the axis Q, which is the central axis of the valve port 620, which will be described later, is improved.

[0054] On the other hand, the (-Z) portion of the valve seat fixing portion 605 forms a brazing material impregnated portion. That is, the outer surface of the (-Z) side end of the valve seat 62 is fixed by welding using brazing material to the inner surface of the brazing material impregnated portion of the valve seat fixing portion 605. As a result, after the assembly process is completed, the valve housing 60 and the valve seat 62 form an integrated structure.

[0055] The opening on the (+Z) side of the valve seat 62, which is a substantially cylindrical member, forms the valve port 620. Therefore, when the valve seat 62 is fixed to the valve housing 60 (valve seat fixing portion 605), the interior of the valve seat 62 and the intra-valve flow path 600 of the valve housing 60 are connected in communication. In other words, the valve port 620 serves as an inlet and outlet for the refrigerant 90 in the intra-valve flow path 600.

[0056] The thickness of valve seat 62, which is a substantially cylindrical member, varies in the center and is designed to be thinner on the (-Z) side. That is, the inner diameter of valve seat 62 varies in the center, forming a step, which forms first piping fixing portion 621.

[0057] An end of the pipe 801 is inserted into the first pipe fixing portion 621 and fixed by welding. As a result, the valve seat 62, while fixed to the valve housing 60, further fixes the pipe 801 (first pipe), thereby connecting the flow path formed by the pipe 801 to the internal space of the valve seat 62. As already explained, the internal space of the valve seat 62 and the in-valve flow path 600 are connected in communication. Therefore, the valve seat 62 has the function of connecting the flow path formed by the pipe 801 to the in-valve flow path 600 in communication.

[0058] Furthermore, in the valve device 6, the valve seat 62 and the pipe 801 can be fixed from the same (-Z) direction. Therefore, there is no need to change the position of the valve housing 60 in the process of fixing the valve seat 62 to the valve housing 60 and the process of fixing the pipe 801 to the valve seat 62, improving workability during assembly.

[0059] The valve stem 61 is a generally cylindrical member with an axis S as its central axis, and is made of stainless steel in this example. The valve stem 61 has a long shaft portion and a head portion with an outer diameter larger than that of the shaft portion. In the valve device 6, the valve stem 61 is arranged in the internal valve flow path 600, which is the internal space of the valve housing 60, with the head portion facing in the (-Z) direction and the axis S oriented along the Z-axis direction.

[0060] More specifically, the end (the (+Z) side end) of the shaft portion of the valve stem 61 is inserted in the (+Z) direction from the valve seat fixing portion 605 of the valve housing 60, and the valve stem 61 is placed in the intra-valve flow path 600. In the valve device 6 of this embodiment, the (+Z) side of the valve stem 61 protrudes from the valve housing 60, but is covered by the cover nut 68 so that the valve stem 61 is not exposed to the outside.

[0061] When assembling the valve device 6, after inserting the valve stem 61, the valve seat 62 is fixed to the valve seat fixing part 605. In other words, after the valve stem 61 is enclosed in the valve housing 60, it is covered with the valve seat 62.

[0062] The head portion of the valve stem 61 is chamfered. The tapered surface formed on the (-Z) side of the head portion forms a first seal portion 610. The tapered surface formed on the (+Z) side of the head portion forms a second seal portion 611.

[0063] Although details are omitted, an operator can operate the valve stem 61. When the valve stem 61 is operated, the valve stem 61 rotates around the axis S. Threads and grooves are formed on the inner surface of the valve housing 60 and the outer surface of the valve stem 61. Therefore, by rotating the valve stem 61 around the axis S, the valve stem 61 can advance and retreat along the Z-axis direction.

[0064] When the valve stem 61 advances in the (-Z) direction and the first seal portion 610 abuts against the valve seat 62 (valve port 620), communication between the in-valve flow path 600 of the valve housing 60 and the internal space of the valve seat 62 is blocked. In other words, the movement of the refrigerant 90 between the internal space of the valve seat 62 and the in-valve flow path 600 of the valve housing 60 is blocked. This closes the piping 801, which is the flow path for the refrigerant 90. In the following description, the position of the valve stem 61 when the first seal portion 610 abuts against the valve seat 62 may be referred to as the "closed position."

[0065] The valve seat 62 has an outer periphery of the valve orifice 620 fixed to the valve seat fixing portion 605 of the valve housing 60. This allows the distance between the portion fixing the valve seat 62 and the valve orifice 620 to be designed to be short, further improving the positioning accuracy of the valve orifice 620 in the valve device 6. Therefore, when the valve stem 61 abuts against the valve orifice 620, it is possible to suppress misalignment between the central axis (axis S) of the valve stem 61 and the center (axis Q) of the valve orifice 620. This allows the valve device 6 to improve the sealing effect of the first seal portion 610.

[0066] When the valve stem 61 retracts in the (+Z) direction and the first seal portion 610 separates from the valve seat 62, the valve port 620 opens, and the internal space of the valve seat 62 communicates with the in-valve flow path 600. That is, the refrigerant 90 can move between the internal space of the valve seat 62 and the in-valve flow path 600 of the valve housing 60. This opens the piping 801, which is the flow path for the refrigerant 90. Therefore, the valve seat 62 forms part of the flow path for the refrigerant 90. In the following description, the position of the valve stem 61 when the first seal portion 610 and the valve seat 62 separate may be referred to as the "open position."

[0067] In this way, the valve rod 61 is positioned inside the valve housing 60 by being inserted in the (+Z) direction from the valve seat fixing portion 605, and has the function of closing the intra-valve flow path 600 by abutting against the valve seat 62 from the inside of the valve housing 60 so as to block the valve port 620, while opening the intra-valve flow path 600 by moving away from the valve seat 62.

[0068] When the valve stem 61 further retracts in the (+Z) direction, the second seal portion 611 abuts against the seal portion 604 of the valve housing 60. In this state (the state shown in FIG. 3), the in-valve flow path 600 of the valve housing 60 is divided into two by the head portion of the valve stem 61.

[0069] One of the two separated in-valve flow paths 600 is a portion on the (+Z) side (hereinafter referred to as the "outer portion") and is connected in fluid communication with the supply flow path 602. The other of the two separated in-valve flow paths 600 is a portion on the (-Z) side (hereinafter referred to as the "inner portion"). When the valve stem 61 is in the open position, the inner portion of the in-valve flow path 600 is a portion that is connected in fluid communication with the flow path of the refrigerant 90 formed by the pipes 801 and 802.

[0070] By dividing the in-valve flow path 600 into an outer portion and an inner portion in this manner, the second seal portion 611 and the seal portion 604 have the function of sealing (hermetically sealing) the in-valve flow path 600 (particularly the inner portion of the in-valve flow path 600) so that the refrigerant 90 does not leak to the outside. Therefore, the sealing effect is improved compared to when sealing is performed only by a V-packing provided on the valve stem 61.

[0071] Furthermore, in the valve device 6, the position at which the second seal portion 611 and the seal portion 604 seal so as to divide the in-valve flow path 600 is on the (-Z) side of the position at which the refrigerant 90 is supplied by the supply flow path 602. In other words, the inner portion of the in-valve flow path 600 can be sealed off from the supply flow path 602. This makes it possible to block the movement of the refrigerant 90 between the pipes 801 and 802 and the supply flow path 602. Therefore, the valve device 6 does not need to provide a seal portion within the supply flow path 602 of the charge port 609, as in the prior art (the art described in JP 2015-169335 A).

[0072] Furthermore, the sealing provided by the seal portion 604 and the second seal portion 611 is as strong as the sealing provided by the first seal portion 610 and the valve seat 62 (valve port 620). Therefore, the valve device 6 can also accommodate high-pressure refrigerant 90, and carbon dioxide, for example, can be used as the refrigerant 90.

[0073] Although not shown in detail, a V-packing is attached to the shaft portion of the valve stem 61, providing a seal to prevent refrigerant 90 from leaking to the outside through a gap between the inner surface of the valve housing 60 and the outer surface of the valve stem 61. As the V-packing is a conventional technique, a detailed description thereof will be omitted.

[0074] Next, the effects of the valve device 6 will be described in more detail using a comparative example.

[0075] Fig. 4 is a cross-sectional view showing a comparison target of the valve device 6. In Fig. 4, the valve device 100, which is a comparison target of the valve device 6, is shown connected to pipes 801 and 802. Positions P1, P2, and P3 indicated by thick arrows in Fig. 4 all indicate welding positions.

[0076] The valve device 100 is significantly different from the valve device 6 in that it is divided into a first valve housing that houses the valve stem and a second valve housing that has a valve port. Due to this structure, the valve device 100 uses welding at positions P1, P2, and P3.

[0077] First, fixing at position P1 poses the problem that the size of the part (second valve housing) in the Z direction is large, making press-fitting precision unstable and unsuitable for fixation. Therefore, at position P1, a clearance is typically formed between the first valve housing and the second valve housing beforehand, allowing the position to be adjusted later. However, such adjustment reduces the coaxiality between the valve stem and the valve port (the degree of alignment between axes S and Q in the valve device 6), making it difficult to increase the design pressure as desired. Another problem is that the yield in the manufacturing process decreases.

[0078] In contrast, as already explained, in the valve device 6, the valve seat 62 having the valve port 620 is fixed by press-fitting into the press-fit portion of the valve seat fixing portion 605 of the valve housing 60. This improves the coaxiality between the axis S (valve stem 61) and the axis Q (valve port 620). Furthermore, since the valve seat 62 in the valve device 6 is temporarily positioned by press-fitting, it is also possible to transport the part (the article in which the valve seat 62 is press-fitted into the valve housing 60) before fixing by welding. This improves the versatility of the manufacturing process.

[0079] Furthermore, in the valve device 100, the distance in the Z-axis direction between position P1 (fixed position) and the valve orifice is large, which further reduces the coaxiality between the valve stem and the valve orifice. In contrast, in the valve device 6, the outer periphery of the valve orifice 620 is fixed to the valve housing 60, which makes it possible to reduce the distance in the Z-axis direction between the fixed position and the valve orifice 620. Therefore, as already explained, the positional accuracy of the valve orifice 620 is improved, and the coaxiality between the axis S (valve stem 61) and the axis Q (valve orifice 620) is further improved.

[0080] Furthermore, position P1 in the valve device 100 is relatively close to the valve stem. Although not shown in the figure, a resin V-packing is used for the valve stem, which is vulnerable to high heat. In other words, if welding is performed near the valve stem, a distance from the V-packing must be secured, which poses a problem in that the size of the valve stem in the Z-axis direction cannot be reduced.

[0081] In contrast, in the valve device 6, the position corresponding to position P1 is the position of the valve seat fixing portion 605, which is a position relatively far from the valve stem 61. Therefore, the sizes of the valve housing 60 and the valve stem 61 in the Z-axis direction can be reduced, and the valve device 6 can be made more compact.

[0082] Furthermore, in the valve device 100, since position P1 and position P3 are located apart, welding at position P1 and welding at position P3 need to be performed as separate processes. In contrast, in the valve device 6, the valve seat fixing portion 605 and the first piping fixing portion 621 are located close to each other, so welding using brazing material can be performed at two locations simultaneously.

[0083] Furthermore, because the welding directions at positions P1 and P3 in the valve device 100 are opposite, a step of changing the orientation of the members is required between the welding step at position P1 and the welding step at position P2. In contrast, this is not necessary in the valve device 6. Therefore, the number of steps in the manufacturing process can be reduced.

[0084] As described above, the valve device 6, which opens and closes the flow path of the refrigerant 90 between the external pipes 801 and 802, comprises the valve housing 60, which defines the in-valve flow path 600; the valve seat 62, which is fixed to the valve housing 60 and has the valve port 620, which serves as an inlet and outlet for the in-valve flow path 600; and the valve stem 61, which is disposed inside the valve housing 60 and abuts against the valve seat 62 from inside the valve housing 60 to block the valve port 620, thereby closing the in-valve flow path 600, and opening the in-valve flow path 600 by moving away from the valve seat 62. The valve housing 60 also comprises a charge port 609, which has a supply flow path 602 formed therein, for supplying the refrigerant 90 from the outside into the in-valve flow path 600, and a seal portion 604 protruding into the in-valve flow path 600. The valve stem 61 abuts against the seal portion 604 of the valve housing 60, thereby blocking the movement of the refrigerant 90 between the supply flow path 602 and the pipes 801 and 802. This improves the sealing effect between the connected pipes (pipes 801, 802) and the outside of the valve device 6. Therefore, the valve device 6 can be used with the refrigerant 90 used in a higher pressure state than before.

[0085] Furthermore, because the valve housing 60 is molded as a single piece, the number of parts to be manufactured by forging, for example, can be reduced compared to when the valve housing 60 (intra-valve flow path 600) is formed from multiple parts.

[0086] Furthermore, the valve seat 62 is fixed at the outer periphery of the valve port 620 to the valve housing 60. This reduces the distance between the part where the valve seat 62 is fixed and the valve port 620, resulting in high positioning accuracy (it is easy to align the axes).

[0087] Furthermore, the valve housing 60 is provided with a press-fit portion into which the valve seat 62 is press-fitted, thereby further increasing the positioning accuracy (making it easier to align the axes).

[0088] Furthermore, the valve seat 62 includes a first pipe fixing portion 621 that fixes the pipe 801 while being fixed to the valve housing 60, thereby connecting the pipe 801 to the in-valve flow path 600. This makes it easy to fix the valve seat 62 and the pipe 801.

[0089] The valve housing 60 also includes a second pipe fixing portion 608 that fixes the pipe 802 and connects the pipe 802 to the in-valve flow path 600. This makes it possible to fix the pipe 802 easily.

[0090] <2. Variations> Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments and can be modified in various ways.

[0091] For example, in the above embodiment, it has been described that the seal portion 604 is a convex portion and the first seal portion 610 is a tapered surface. However, for example, the seal portion 604 may be a tapered surface and the first seal portion 610 may be a convex portion.

[0092] Furthermore, the mounting portions 606 and 607 have been described as constituting a part of the valve housing 60, but for example, members manufactured as separate members may be attached to the valve housing 60 as the mounting portions 606 and 607.

[0093] Moreover, the air conditioner 1 is configured as both a cooling device and a heating device. However, the air conditioner 1 may be configured as either a cooling device or a heating device.

[0094] Furthermore, the pipe attached to the valve device 6 is not limited to the pipe 80. Any pipe may be used as long as it is located on the flow path of the refrigerant 90 and can appropriately open and close the flow path. [Explanation of symbols]

[0095] 1 Air conditioner 2 Indoor unit 20 Indoor heat exchanger 21,31 Fans 3 Outdoor unit 30 Outdoor heat exchanger 32 Case 4 Compressor 5 Separator 6,100 valve devices 60 Valve housing 600,601 Valve internal flow path 602 Supply channel 604,610,611 Seal part 605 Valve seat fixing part 606,607 Mounting part 608 2nd piping fixing part 609 Charging Port 61 Valve stem 62 Valve seat 620 Valve Orifice 621 1st piping fixing part 68 Lid nut 69 Charge port nut 8 Four-way valve 80,801,802,81,82,83,84,85,86 Piping 90 Refrigerant 91 Refrigerating machine oil

Claims

1. A valve device that opens and closes a flow path of a refrigerant between an external first pipe and an external second pipe, a valve housing that defines an internal flow path of the valve; a valve seat fixed to the valve housing and having a valve port formed therein, the valve port serving as an inlet and outlet of the internal valve flow path; a valve stem disposed inside the valve housing, the valve stem abutting against the valve seat from inside the valve housing to close the valve port, thereby closing the intra-valve flow path, and separating from the valve seat, thereby opening the intra-valve flow path; Equipped with The valve housing includes: a charge port having a supply passage formed therein for supplying the refrigerant from the outside into the valve passage; a seal portion protruding into the valve internal flow path; Equipped with The valve device wherein the valve rod abuts against the seal portion of the valve housing to block movement of the refrigerant between the first pipe and the second pipe and the supply flow path.

2. 2. The valve device according to claim 1, The valve device wherein the valve housing is integrally molded.

3. 2. The valve device according to claim 1, The valve seat is The valve device has an outer periphery of the valve port fixed to the valve housing.

4. 2. The valve device according to claim 1, The valve housing includes: A valve device comprising a press-fit portion into which the valve seat is press-fit.

5. 2. The valve device according to claim 1, The valve seat is a first pipe fixing portion that is fixed to the valve housing and fixes the first pipe, thereby connecting the first pipe to the valve internal flow path;

6. 2. The valve device according to claim 1, The valve housing includes: a second pipe fixing portion that fixes the second pipe and connects the second pipe to the valve internal flow path;

7. An air conditioning device, a first pipe and a second pipe that form a flow path of a refrigerant; a valve device that opens and closes a flow path of the refrigerant between the first pipe and the second pipe; Equipped with The valve device a valve housing that defines an internal flow path of the valve; a valve seat fixed to the valve housing and having a valve port formed therein, the valve port serving as an inlet and outlet of the internal valve flow path; a valve stem disposed inside the valve housing, the valve stem abutting against the valve seat from inside the valve housing to close the valve port, thereby closing the intra-valve flow path, and separating from the valve seat, thereby opening the intra-valve flow path; Equipped with The valve housing includes: a charge port having a supply passage formed therein for supplying the refrigerant from the outside into the valve passage; a seal portion protruding into the valve internal flow path; Equipped with The valve rod abuts against the seal portion of the valve housing to block movement of the refrigerant between the first pipe and the second pipe and the supply flow path.

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