CN116892802A - Refrigerant piping, connection structure for refrigerant piping, and valve device - Google Patents

Abstract

The invention provides a refrigerant pipe, a connection structure of the refrigerant pipe and a valve device, which can be easily connected by brazing even though materials are different. In a joint member (100) made of stainless steel, a copper or copper alloy connection auxiliary portion (200) is provided on at least one of the inner peripheral surface (100 a) and the outer peripheral surface (100 b) of one end in the longitudinal direction, or on both surfaces thereof. Therefore, even when the joint member (100) itself is made of stainless steel, the joint member can be easily connected to a connection object by brazing through the end portion of the connection auxiliary portion (200) provided with copper or copper alloy.

Description

Refrigerant piping, connection structure for refrigerant piping, and valve device

Technical Field

The present invention relates to a refrigerant pipe, a connection structure of the refrigerant pipe, and a valve device.

Background

Conventionally, in an air conditioning apparatus such as an indoor air conditioner, a direction of a refrigerant is reversed so that the refrigerant flows back to the compressor through a compressor, an outdoor heat exchanger, an expansion valve, and an indoor heat exchanger connected via refrigerant pipes during a cooling operation, and the refrigerant flows back to the compressor through the compressor, the indoor heat exchanger, the expansion valve, and the outdoor heat exchanger during a heating operation. As a flow path switching valve (so-called four-way switching valve) of a valve device for reversing a return flow path of a refrigerant, a sliding type switching valve having a valve body slidably provided in a valve body is widely used (for example, refer to patent document 1). In such an air conditioning apparatus, a refrigerant pipe disposed in the apparatus and a joint member (refrigerant pipe) provided as a discharge pipe and a suction pipe of the sliding type switching valve are connected by brazing.

Prior art literature

Patent literature

Patent document 1: japanese patent application laid-open No. 2004-125238

Disclosure of Invention

Problems to be solved by the invention

However, the valve device (sliding type switching valve) is generally made of brass, and other parts such as joint members are made of copper. However, in recent years, due to the rapid increase in the price of copper, there is a tendency to substitute copper used conventionally for stainless steel as a material of a joint member in a valve device. On the other hand, in an air conditioner equipped with a valve device, copper is used as a material of the refrigerant piping without change from the prior art because of easiness of processing and stability of performance. Therefore, the stainless-tempered joint member of the valve device and the copper refrigerant pipe of the air conditioner are different in material from each other, and thus there is a problem that it is difficult to simply connect by brazing as in the prior art.

In addition, in the case of using a flux ensuring wettability in brazing a joint member of a valve device and a refrigerant pipe of an air conditioner, the removal of the flux is time-consuming and laborious, and thus, no flux has been used conventionally. That is, since the refrigerant piping containing stainless steel in the raw material and the joint member containing copper in the raw material are different in material, and no flux is used, brazing them is a very difficult operation.

The present invention has been made in view of the above-described problems, and an object thereof is to provide a refrigerant pipe, a connection structure of the refrigerant pipe, and a valve device that can be easily connected by brazing even when materials are different from each other.

Means for solving the problems

The refrigerant piping of the present invention is a refrigerant piping made of stainless steel, and is characterized in that a thin plate-shaped connection auxiliary portion made of copper or copper alloy is provided at least on an inner peripheral surface, an outer peripheral surface, or both surfaces of one end portion in a longitudinal direction, and a melt-solidified layer of brazing filler metal is formed between the inner peripheral surface, the outer peripheral surface, or both surfaces and the connection auxiliary portion.

According to the present invention, even when the refrigerant pipe itself is made of stainless steel, since the thin plate-shaped connection auxiliary portion made of copper or copper alloy is provided on at least the inner peripheral surface, the outer peripheral surface, or both surfaces of one end portion in the longitudinal direction, which is joined via the melt-solidified layer of brazing material (that is, by brazing), it is possible to easily connect to a connection object by brazing via the connection auxiliary portion. In addition, the wall thickness (thickness) of the connection auxiliary portion can be reduced in comparison with the case where a member such as a copper ring or a sleeve is provided for connection with another refrigerant pipe to be connected, and accordingly, the connection cost such as the material cost can be reduced. Further, since heat of brazing is easily transferred when the connecting object is connected to the connecting object, overheating at the time of the brazing can be suppressed, and the gap between the connecting object and the connecting object can be stabilized, thereby improving the quality of the brazing.

In this case, in the refrigerant pipe according to the present invention, it is preferable that the connection auxiliary member is arranged to be pressed by an inner peripheral surface, an outer peripheral surface, or both of the refrigerant pipe. According to this structure, the labor for holding the arrangement portion by spot welding or the like can be eliminated, and the arrangement can be easily performed. Further, it is preferable that the connection auxiliary portion is arranged in a state of being bent in a C-shape when viewed from a direction orthogonal to the axial direction. According to such a configuration, when the connection auxiliary portion is disposed on the inner peripheral surface of the end portion of the refrigerant pipe, the connection auxiliary portion is pressed and held on the inner peripheral surface of the refrigerant pipe by the elastic force for performing shape retention in the opening direction from the state of being bent in the C-shape, and when the connection auxiliary portion is disposed on the outer peripheral surface of the end portion of the refrigerant pipe, the connection auxiliary portion is held on the outer peripheral surface of the refrigerant pipe by the elastic force for performing shape retention in the direction of being bent in the C-shape, so that the connection auxiliary portion can be easily disposed with a simple configuration.

In the refrigerant pipe according to the present invention, it is preferable that the connection auxiliary portion is an annular cylindrical body. According to this configuration, the connection auxiliary portion of the tubular body is expanded in the outer diameter direction or contracted in the inner diameter direction according to the arrangement portion, so that the labor for holding the connection auxiliary portion in the arrangement portion by spot welding or the like can be eliminated, and the connection auxiliary portion can be easily arranged.

In the refrigerant pipe according to the present invention, it is preferable that the connection auxiliary portion is provided so as to extend to an end face of the one end portion. According to this structure, since the connection auxiliary portion is provided so as to extend to the end face of the refrigerant pipe in addition to the face (inner peripheral face or outer peripheral face) that contacts the face (outer peripheral face or inner peripheral face) to be connected in the refrigerant pipe, it is easy to form the rounded corner well when the material to be connected is copper or copper alloy that is the same as that of the connection auxiliary portion. This ensures that the brazing portion is reliably air-tight, and the joining reliability is further ensured. In this case, it is preferable that the connection auxiliary portion has a flange portion facing the end surface, and a melt-solidified layer of the brazing filler metal is formed between the flange portion and the end surface. Thus, the connection auxiliary portion extending to the end face of the refrigerant pipe can be easily provided, and thus the reliability of the connection can be more easily ensured.

In the refrigerant pipe according to the present invention, the connection auxiliary portion preferably has a U-shaped cross section, and the one end portion is preferably inserted into an inner peripheral side of the U-shape. According to this configuration, not only can both the outer peripheral surface and the inner peripheral surface of the end portion of the refrigerant pipe be easily provided, but also the connection auxiliary portion integrally covering the end surface of the refrigerant pipe can be easily provided, so that when the material to be connected is copper or copper alloy identical to that of the connection auxiliary portion, the rounded corners can be easily formed. This allows the joining to be performed without any gap, and the air tightness of the soldered portion can be reliably ensured, so that a structure that can further ensure the reliability of the connection can be easily realized.

In the refrigerant pipe according to the present invention, it is preferable that a pipe stopper portion is formed at a portion where an inner end portion of the connection auxiliary portion in the longitudinal direction of the refrigerant pipe is located, and the pipe stopper portion restricts an insertion amount of another refrigerant pipe to be connected. With this configuration, the amount of insertion of the refrigerant pipe (joint member) to be connected can be easily limited, and sagging of the brazing filler metal used for brazing can be prevented.

In this case, the pipe stopper preferably protrudes outward from the outer peripheral surface of the refrigerant pipe or inward from the inner peripheral surface. According to this configuration, the pipe stopper portion can be formed integrally with the refrigerant pipe, so that it is unnecessary to provide a separate pipe stopper portion, and the number of parts can be suppressed.

In the refrigerant pipe according to the present invention, it is preferable that a pipe stopper is formed at an inner end portion in the longitudinal direction of the connection auxiliary portion in a state where the connection auxiliary portion is provided in the refrigerant pipe, and the pipe stopper regulates an insertion amount of another refrigerant pipe to be connected. With this configuration, the amount of insertion of the refrigerant pipe (joint member) to be connected can be easily limited, and sagging of the brazing filler metal used for brazing can be prevented.

In this case, the pipe stopper preferably protrudes outward from the outer peripheral surface of the connection auxiliary portion, inward from the inner peripheral surface, or both. According to this configuration, the pipe stopper portion and the connection auxiliary portion can be integrally formed, so that it is unnecessary to separately provide the pipe stopper portion, and the number of parts can be suppressed. Further, it is preferable that the connection auxiliary portion has a thickness smaller than that of the refrigerant pipe. In addition, it is preferable that the thickness of the melt-solidified layer is smaller than the thickness of the connection auxiliary portion.

The connection structure of the refrigerant piping according to the present invention is a connection structure of refrigerant piping for connecting a first refrigerant piping and a second refrigerant piping by brazing, wherein the first refrigerant piping is made of stainless steel, a thin plate-shaped connection auxiliary portion made of a second metal material different from stainless steel is joined to an inner peripheral surface, an outer peripheral surface, or both surfaces of an end portion on the side of the second refrigerant piping via a melt-solidified layer of brazing material, and the second refrigerant piping is made of the second metal material, or a thin plate-shaped connection auxiliary portion using the second metal material is joined to an outer peripheral surface, an inner peripheral surface, or both surfaces of an end portion on the side of the first refrigerant piping via a melt-solidified layer of brazing material. According to the present invention, even when the first refrigerant pipe is made of stainless steel, the second refrigerant pipe to be connected to the second refrigerant pipe is easily connected by brazing, because the connection auxiliary portion made of the second metal material (for example, copper alloy, aluminum, or the like) is provided on the inner peripheral surface, the outer peripheral surface, or both surfaces of the second refrigerant pipe side end portion, and the connection auxiliary portion made of the second metal material is provided on the inner peripheral surface, the outer peripheral surface, or both surfaces of the first refrigerant pipe side end portion.

In the connection structure of the refrigerant pipe according to the present invention, it is preferable that the connection auxiliary portion is formed to extend to an end face of the second refrigerant pipe at the first refrigerant pipe side end portion when the end face of the second refrigerant pipe at the second refrigerant pipe side end portion and the second refrigerant pipe are not made of the second metal material. According to this configuration, since the connection support portion is provided so as to extend to the end face of the connection target side end portion of both the first and second refrigerant pipes, in addition to the face (outer peripheral surface or inner peripheral surface) of the connection target side end portion of both the first and second refrigerant pipes, when the material of the second refrigerant pipe to be connected to the first refrigerant pipe or the connection support portion provided at the first refrigerant pipe side end portion is the same as the second metal material of the connection support portion of the first refrigerant pipe, it is easy to form the rounded corner satisfactorily. This ensures that the brazing portion is reliably air-tight, and the joining reliability is further ensured. Further, it is preferable that the connection auxiliary portion is provided so as to extend to an end surface of the second refrigerant pipe side end portion of the first refrigerant pipe. Further, it is preferable that the connection auxiliary portion has a flange portion facing the end surface, and a melt-solidified layer of solder is formed between the flange portion and the end surface. Further, it is preferable that the connection auxiliary portion has a thickness smaller than that of the first refrigerant pipe. In addition, it is preferable that the thickness of the melt-solidified layer is smaller than the thickness of the connection auxiliary portion.

The valve device according to the present invention is a valve device in which a joint member is connected to a valve body, wherein any one of the refrigerant pipes is used as the joint member. According to the present invention, even when the joint member is made of stainless steel, the joint-side end portion of the joint member is provided with the connection auxiliary portion of copper or copper alloy on the inner peripheral surface, the outer peripheral surface, or both surfaces thereof, as in the above-described case, and therefore, the joint member can be easily connected to the refrigerant pipe to be connected by brazing. In addition, the same effects as those of the above-described refrigerant pipes can be obtained.

Effects of the invention

According to the refrigerant pipe, the connection structure of the refrigerant pipe, and the valve device of the present invention, even when materials are different from each other, the refrigerant pipe, the connection structure, and the valve device can be easily connected by brazing.

Drawings

Fig. 1 is a sectional view showing a sliding type switching valve according to an embodiment.

Fig. 2 is a cross-sectional view showing an end portion of a joint member provided in the sliding type switching valve of fig. 1, and showing a state in which a connection auxiliary portion is provided on an inner peripheral surface.

Fig. 3 is a cross-sectional view showing an enlarged main portion of an end portion of the joint member of fig. 2.

Fig. 4 is a cross-sectional view showing an end portion of a joint member according to a modification, and showing a state in which a connection auxiliary portion is provided on an inner peripheral surface.

Fig. 5 is a cross-sectional view showing an end portion of the joint member according to modification 2, and showing a state in which the connection auxiliary portion according to modification 2 is provided on the inner peripheral surface.

Fig. 6 is a front view of the connection support portion provided in the joint member of fig. 5, and (a) is a front view of the connection support portion viewed in a direction perpendicular to the axial direction, and (b) is a cross-sectional view taken along the axial direction.

Fig. 7 is an enlarged cross-sectional view of a main portion showing a connection state between a joint member and a refrigerant pipe in the sliding type switching valve of fig. 5.

Fig. 8 is a cross-sectional view showing an end portion of the joint member according to modification 3, and showing a state in which the connection auxiliary portion according to modification 3 is provided on the inner peripheral surface.

Fig. 9 is a front view of the connection support portion provided in the joint member of fig. 8, viewed from a direction orthogonal to the axial direction, and (b) is a cross-sectional view taken along the axial direction.

Fig. 10 is a cross-sectional view showing an end portion of the joint member according to modification 4, and showing a state in which the connection auxiliary portion according to modification 4 is provided on the outer peripheral surface.

Fig. 11 is a cross-sectional view showing an end portion of the joint member of modification 5, and showing a state in which the connection auxiliary portion of modification 5 is provided on the outer peripheral surface.

Fig. 12 is a cross-sectional view showing an enlarged main portion of an end portion of the joint member of fig. 11.

Fig. 13 is a cross-sectional view showing an end portion of the joint member according to modification 6, and showing a state in which the connection auxiliary portion according to modification 6 is provided on the outer peripheral surface.

Fig. 14 is an enlarged cross-sectional view of a main portion showing a connection state between a joint member and a refrigerant pipe in the sliding type switching valve of fig. 13.

Fig. 15 is a cross-sectional view showing an end portion of the joint member of modification 7, and showing a state in which the connection auxiliary portion of modification 7 having a U-shaped cross section is provided from the inner peripheral surface to the outer peripheral surface.

Fig. 16 is a cross-sectional view showing an end portion of the joint member according to modification 8, and showing a state in which a connection auxiliary portion according to modification 8 having a U-shaped cross section is provided from the inner peripheral surface to the outer peripheral surface.

Fig. 17 is a cross-sectional view showing an end portion of the joint member of modification 9, and showing a state in which a connection auxiliary portion of modification 9 having a U-shaped cross section from the inner peripheral surface to the outer peripheral surface and having a pipe stopper portion is provided.

Fig. 18 is a cross-sectional view showing an end portion of the joint member of modification 10, and showing a state in which a connection auxiliary portion of modification 10 having a U-shaped cross section from the inner peripheral surface to the outer peripheral surface and having a pipe stopper portion is provided.

In the figure:

1-a valve housing (valve body); 11-a cylindrical portion; 12-a cover part; 2-a piston; 21-a pad; 22-fixed circular plate; 23-leaf spring; 3-a connecting plate; 4-valve seat; 5-a valve core; 10-a sliding switching valve; 100—joint members (refrigerant piping, first refrigerant piping); 100 a-an inner peripheral surface; 100 b-an outer peripheral surface; 100 c-end face; 101-a tubing limit part; 200-a connection auxiliary; 201—end; 202-end; 203-a flange portion; 205—a tubing stop; 300—melt-solidifying layer; 60-refrigerant piping (second refrigerant piping); 60 a-an outer peripheral surface; 60 b-an inner peripheral surface; 60 c-end face; 70—a first rounded corner; 80-second rounded corners.

Detailed Description

Embodiments of the refrigerant piping, the connection structure of the refrigerant piping, and the valve device according to the present invention are described in detail below with reference to the drawings.

As shown in fig. 1, a four-way switching valve (sliding switching valve) 10 of the present embodiment includes a pair of pistons 2L, 2R, a connecting plate 3, a valve seat 4, and a valve body 5 in a valve housing 1 that is a "valve body".

The valve housing 1 is composed of a cylindrical portion 11 made of metal such as stainless steel and two lid portions 12L, 12R made of metal such as stainless steel. The cover portions 12L, 12R are attached to the cylindrical portion 11 so as to close the end of the cylindrical portion 11, respectively. The central axes of the cylindrical portion 11 and the lid portions 12L, 12R become the axis X of the valve housing 1. The pair of pistons 2L, 2R are disposed opposite to each other, and can reciprocate while pressing the packing 21 against the inner peripheral surface of the cylindrical portion 11. Thereby, the interior of the valve housing 1 is partitioned by the two pistons 2L, 2R into the high-pressure chamber 11A in the central portion and the two first and second working chambers 12A, 12B on both sides of the high-pressure chamber 11A. The connecting plate 3 is made of a metal plate, and the connecting plate 3 is disposed between the pistons 2L and 2R so as to be disposed on the axis X of the valve housing 1, and holds the valve element 5 at the center thereof. In addition, a through hole 3a is formed in the connecting plate 3. When the pistons 2L and 2R move, the valve body 5 slides on the valve seat 4 in conjunction with the connecting plate 3, and stops at a predetermined left and right position.

The valve seat 4 is disposed in the middle portion of the cylindrical portion 11, and a D-joint pipe 13D, which is a joint member that is a refrigerant pipe of the present embodiment that opens in the cylindrical portion 11, is attached to the middle portion of the cylindrical portion 11 at a position facing the valve seat 4. The valve seat 4 is provided with an E-joint pipe 13E, an S-joint pipe 13S, and a C-joint pipe 13C, which are aligned in a straight line in the axis X direction of the valve housing 1 and serve as joint members as refrigerant pipes in the present embodiment. A bowl-shaped recess 5A is formed inside the valve body 5. The valve body 5 communicates the S-joint pipe 13S with the E-joint pipe 13E through the bowl-shaped recess 5A at the left end position in fig. 1. At this time, the C-joint pipe 13C is mainly connected to the D-joint pipe 13D through the through hole 3a of the connecting plate 3 in the high pressure chamber 11A. The valve body 5 communicates the S-joint pipe 13S with the C-joint pipe 13C through the bowl-shaped recess 5A at the right end position in fig. 1. At this time, the E-joint pipe 13E is mainly connected to the D-joint pipe 13D through the through hole 3a in the high pressure chamber 11A.

Here, the sliding type switching valve 10 of the present embodiment is provided in a refrigeration cycle, for example, not shown. In addition, since a general refrigeration cycle can be widely applied as the refrigeration cycle, illustration is omitted here for convenience.

In this refrigeration cycle, the D-joint pipe 13D is connected to the discharge port of the compressor, and the S-joint pipe 13S is connected to the suction port of the compressor. The C-joint pipe 13C is connected to the outdoor heat exchanger, and the E-joint pipe 13E is connected to the indoor heat exchanger. The outdoor heat exchanger and the indoor heat exchanger are connected via a throttle device. The refrigeration cycle is constituted by a path from the C-joint pipe 13C to the outdoor heat exchanger, the throttle device, the indoor heat exchanger, and the E-joint pipe 13E, and a path from the S-joint pipe 13S to the compressor and the D-joint pipe 13D. In addition, the refrigerant in the refrigeration cycle contains a small amount of refrigerating machine oil in order to protect the compressor and other equipment.

The pilot valve is connected to the sliding type switching valve 10. The pilot valve has the same structure as the sliding type switching valve 10, and switches the flow path by moving the valve body by an electromagnetic actuator or the like. In addition, in the pilot valve, the connection destination of the pipe that communicates with the S-joint pipe 13S of the sliding type switching valve 10 that connects to the suction port of the compressor is switched by the pressure introduction pipe 14L that communicates with the first working chamber 12A on the left side of the sliding type switching valve 10 and the pressure introduction pipe 14R that communicates with the second working chamber 12B on the right side, and at the same time, the connection destination of the pipe that communicates with the D-joint pipe 13D of the sliding type switching valve 10 that connects to the discharge port of the compressor is switched by the pressure introduction pipe 14R and the pressure introduction pipe 14L. By this, the pistons 2L, 2R, the connecting plate 3, and the valve body 5 move along the axis X of the valve housing 1 by a pressure difference between the pressure of the first working chamber 12A, into which the suction pressure or the discharge pressure of the compressor is introduced, and the pressure of the second working chamber 12B on the opposite side, and the position of the valve body 5 is switched to switch the flow path of the refrigeration cycle.

With the above configuration, the high-pressure refrigerant compressed by the compressor flows into the main valve chamber 11A from the D joint pipe 13D, and in the state of the cooling operation, the high-pressure refrigerant flows into the outdoor heat exchanger from the C joint pipe 13C. In addition, in the state of the switching valve element 5 in the heating operation, the high-pressure refrigerant flows into the indoor heat exchanger from the E-joint pipe 13E. That is, during the cooling operation, the refrigerant discharged from the compressor circulates through the C-joint pipe 13C, the outdoor heat exchanger, the throttle device, the indoor heat exchanger, and the E-joint pipe 13E, and the outdoor heat exchanger functions as a Condenser (Condenser) and the indoor heat exchanger functions as an Evaporator (Evaporator) to perform cooling. In addition, the refrigerant circulates in the opposite direction during the heating operation, the indoor heat exchanger functions as a condenser, and the outdoor heat exchanger functions as an evaporator, and heating is performed.

As shown in fig. 1, each piston 2L, 2R of the sliding type switching valve 10 has a mirror-symmetrical structure. The pistons 2L and 2R each include a packing 21, a fixed disk 22 fixed to the connecting plate 3, a leaf spring 23, and a disk-shaped stopper 24. The packing 21, the fixed disk 22, the leaf spring 23, and the stopper plate 24 are coaxially arranged about the axis X, are fixed as a unit by rivets, and the integrated pistons 2L and 2R are fixed to the connecting plate 3 by bolts.

Hereinafter, the D-joint pipe 13D, the E-joint pipe 13E, the S-joint pipe 13S, and the C-joint pipe 13C, which are joint members that are refrigerant pipes mounted to the sliding type switching valve 10 having such a configuration, will be described. Hereinafter, these D-joint pipes 13D, E-joint pipes 13E, S-joint pipes 13S, and C-joint pipes 13C are collectively referred to as joint members 100. In the following, the case where the connection support portion 200 described later is provided on the inner peripheral surface, the case where the connection support portion is provided on the outer peripheral surface, and the case where the connection support portion is provided on both surfaces of the inner peripheral surface and the outer peripheral surface will be described in order using fig. 2 to 9, 10 to 14, and 15 to 18, respectively, for the joint member 100.

As shown in fig. 2 and 3, the joint member 100 of the refrigerant pipe according to the present embodiment is made of stainless steel, and a connection auxiliary portion 200 is provided on an inner peripheral surface 100a of at least one end portion in the longitudinal direction, and the connection auxiliary portion 200 is also called a thin plate-like backing plate made of copper or copper alloy (here, phosphor bronze containing tin) which is soldered. Preferably, the connection auxiliary portion 200 is formed of a sheet-like body in a strip-like state having a thickness of 0.05mm to 0.5 mm.

As shown in fig. 2, the connection auxiliary portion 200A is arranged in a state of being bent in a C-shape when viewed from a direction orthogonal to the axial direction on the inner peripheral surface 100A of one end portion in the longitudinal direction of the joint member 100. At this time, the end 201 and the end 202 of the connection auxiliary portion 200A facing each other may be disposed in contact with each other or may be disposed at a distance from each other.

The connection auxiliary portion 200 is disposed via a melt-solidified layer 300 of solder (here, phosphor bronze including tin) formed on the inner peripheral surface 100a of one end portion of the joint member 100, and is firmly joined by brazing in which an oxide film formed on the surface of the inner peripheral surface 100a of the joint member 100 is removed and joined. For example, a redox furnace may be used for removing the oxide film, and thus brazing may be performed in an environment where the oxide film can be removed. In this case, the thickness of the connection auxiliary portion 200 is preferably smaller than the thickness of the joint member 100. This reduces the influence of thermal expansion and thermal contraction in the connection auxiliary portion 200, and can suppress the connection auxiliary portion 200 from being peeled off from the joint member 100. In addition, the thickness of the melt-solidified layer 300 is preferably smaller than the thickness of the connection auxiliary portion 200. This suppresses variation in the thickness of the melt-solidified layer 300 of the solder, and can suppress variation in the mounting position of the connection auxiliary portion 200 with respect to the inner peripheral surface 100a of the joint member 100. In addition, the thickness of the melt-solidified layer 300 of the solder is preferably 25% or less of the thickness of the connection auxiliary portion 200. By setting the thickness of the melt-solidified layer 300 of the solder to 10% or more of the thickness of the connection auxiliary portion 200, the strength of the melt-solidified layer 300 can be maintained. In addition, the melting point of the connection auxiliary portion 200 is higher than that of the melt-solidified layer 300.

The connection auxiliary portion 200 is provided in the joint member 100 within a range substantially equal to the length of insertion of another refrigerant pipe 60 (see fig. 7) to be connected, which will be described later. Specifically, the connection auxiliary portion 200 is provided over a range that can sufficiently satisfy the brazing strength with the refrigerant pipe connected to the joint member 100, specifically, over at least a range of a length equal to or greater than the wall thickness of the joint member 100, preferably over a range of a length equal to or greater than half the inner diameter of the joint member 100, and more preferably over a range of a length equal to or greater than the inner diameter of the joint member 100, from the end surface of the joint member 100 toward the inside in the longitudinal direction.

In the present embodiment, the joint member 100 is formed with a pipe stopper 101 for restricting the insertion amount of another refrigerant pipe to be connected at a position where the inner end of the connection auxiliary portion 200 is located in the longitudinal direction. At this time, the pipe stopper 101 is formed to protrude inward from the inner peripheral surface 100a of the joint member 100 by roll processing (internal pin). As shown in fig. 4, the pipe stopper 101 may protrude outward from the outer peripheral surface 100b of the joint member 100. In this case, in other words, the pipe stopper 101 is formed by expanding the end portion of the joint member 100 where the connection auxiliary portion 200 is provided, from the other portion. According to such a configuration, the amount of insertion of the refrigerant pipe (joint member) to be connected can be easily limited, and sagging of a brazing filler metal (here, a phosphor-copper brazing filler metal containing no tin) used for brazing, which will be described later, can be prevented. Further, since the pipe stopper 101 can be integrally formed with the joint member 100, it is not necessary to provide a separate part, and the number of parts can be suppressed.

The present embodiment described above has the following effects. That is, when the joint member 100 itself is made of a material including stainless steel, the connection auxiliary portion 200 of copper or copper alloy as the second metal material is provided on the inner peripheral surface 100a thereof. Therefore, as shown in fig. 7 described later, the refrigerant pipe 60 inserted into the joint member 100 and the joint member 100 can be easily connected by brazing via the connection auxiliary portion 200.

At this time, in the joint member 100, the connection auxiliary portion made of copper or copper alloy forming the connection auxiliary portion 200 is a thin plate-like sheet-like body, and is preferably arranged in a state of being bent in a C-shape. According to such a configuration, when the connection auxiliary portion 200 is disposed on the inner peripheral surface of the end portion of the joint member 100, the connection auxiliary portion 200, which is a sheet-like body elastically deformed to an extent that is smaller than the inner diameter of the joint member 100, is held on the inner peripheral surface of the refrigerant pipe by an elastic force for holding the shape in the opening direction from the state of being bent in the C-shape, and when the connection auxiliary portion 200 is disposed on the outer peripheral surface of the end portion of the refrigerant pipe, the connection auxiliary portion 200, which is plastically deformed to an inner diameter that is smaller than the outer diameter of the joint member 100, is held on the outer peripheral surface of the refrigerant pipe by an elastic force for holding the shape in the direction of being bent in the C-shape, so that, for example, a labor for holding the connection auxiliary portion 200 on the disposition portion by spot welding or the like can be omitted, and the connection auxiliary portion can be easily disposed.

The present invention is not limited to the above-described embodiments, and other configurations, etc., which can achieve the objects of the present invention, are included in the present invention, as are modifications, etc., shown below.

For example, as in modification 2 shown in fig. 5 and 6, it is preferable that a flange 203 bent radially outward is provided at a portion of the connection auxiliary portion 200 that is disposed at the opening-side end portion (end surface 100 c) of the joint member 100. Thus, when the connection auxiliary portion 200 is arranged in the opening end portion of the joint member 100 in a state of being bent in a C-shape, the flange portion 203 faces the end surface 100C of the joint member 100, and the connection auxiliary portion 200 can be easily positioned with respect to the opening end portion. Further, since the melt-solidified layer 300 of the brazing filler metal is formed between the flange 203 and the end face 100c of the joint member 100, the connection auxiliary 200 extending to the end face 100c of the joint member 100 can be easily provided, and the reliability of connection can be more easily ensured.

As described above, in the stainless steel joint member 100 having the thin plate-like connection auxiliary portion 200 made of phosphor bronze, as shown in fig. 7, even when the refrigerant pipe 60 in the refrigeration cycle (not shown) connected to the inner peripheral surface 100a side of the joint member 100 is made of copper or copper alloy, it is possible to easily connect by brazing. The brazing filler metal used for connecting the refrigerant pipe 60 to the stainless joint member 200 having the connection auxiliary portion 200 uses a brazing filler metal having a melting point (low solidus temperature) lower than that of the brazing filler metal used for joining the connection auxiliary portion 200 to the joint member 100. For example, a phosphor copper solder containing no tin as described above is used. At this time, since the connection auxiliary portion 200 of phosphor bronze having the flange portion 203 extending to the end face 100c of the joint member 100 is provided in addition to the face (in this case, the inner peripheral face 100 a) that contacts the outer peripheral face 60a of the refrigerant pipe 60 of the joint member 100, when the material of the refrigerant pipe 60 is copper or copper alloy as the second metal material identical to the connection auxiliary portion 200, the first rounded corner 70 for satisfactorily joining the refrigerant pipe 60 is easily formed. This ensures that the brazing portions are bonded with no gap therebetween, and that the brazing portions are reliably airtight. Therefore, the reliability of the connection between the joint member 100 and the refrigerant pipe 60 can be further ensured. Further, the end face 60c side of the refrigerant pipe 60 is in contact with the pipe stopper 101, whereby the amount of insertion of the refrigerant pipe 60 into the joint member 100 can be easily restricted, and sagging of the brazing filler metal used for brazing can be prevented. In addition, when the material of the refrigerant pipe 60 is copper or a copper alloy as the second metal material similar to the connection auxiliary portion 200, the second rounded corner 80 for satisfactorily joining the refrigerant pipe 60 is easily formed between the end face 60c side of the refrigerant pipe 60 and the connection auxiliary portion 200. This ensures that the joint member 100 is joined without gaps, and the gas tightness of the soldered portion can be reliably ensured, thereby further improving the reliability of the connection between the joint member and the refrigerant pipe 60.

In the joint member 100 as the refrigerant piping of the present embodiment, as in modification 3 shown in fig. 8 and 9, in which the same reference numerals are given to the corresponding parts in fig. 5 and 6, the connection support portion 200A made of copper or copper alloy forming the connection support portion 200 may be formed of an annular tubular body. The connection auxiliary portion 200A shown in fig. 9 has an annular cross section, but may have a substantially polygonal cross section, and the vertex of the substantially polygonal cross section may be pressed into and disposed on the inner peripheral surface of the joint member 100. As a result, the inner peripheral surface 100a is pressed, and therefore, the labor for holding the arrangement portion by spot welding or the like can be eliminated, and the arrangement can be easily performed. In the joint member 100 of each of the modes shown in fig. 2 to 8, the pipe stopper 101 is formed so that the protruding amount thereof protrudes further toward the inside of the joint member 100 than the inner peripheral surface of the connection auxiliary 200. That is, the pipe stopper 101 is formed to have an inner diameter smaller than that of the connection auxiliary 200.

Although the case where the connection support portion 200 is provided on the inner peripheral surface 100a of the joint member 100 has been described, the connection support portion 200 may be provided on the outer peripheral surface 100b of the joint member 100 as in the modifications 4 and 5 shown in fig. 10 and 11, in which the same reference numerals are given to the corresponding portions in fig. 2 and 4. In this way, when the connection auxiliary portion 200 is provided on the outer peripheral surface 100b of the joint member 100, the connection auxiliary portion 200 is formed over a range substantially equal to the length of the joint member 100 inserted into the refrigerant pipe 60 (see fig. 14 described later). Specifically, the brazing strength of the refrigerant pipe connected to the joint member 100 is sufficiently set in a range that extends from the end surface of the joint member 100 to at least a length equal to or longer than the wall thickness of the joint member 100, preferably to at least a length equal to or longer than half the inner diameter of the joint member 100, and more preferably to at least a length equal to or longer than the inner diameter of the joint member 100.

In addition, in the case where the connection support portion 200 is provided on the outer peripheral surface 100b of the joint member 100, as in the case of being provided on the inner peripheral surface 100a, a pipe stopper portion 101 that restricts the insertion amount of another refrigerant pipe to be connected is formed at a portion where the inner end portion of the connection support portion 200 is located in the longitudinal direction of the joint member 100. At this time, as modification 4, the pipe stopper 101 may be formed by bulging (external pins) to protrude outward from the outer peripheral surface 100b of the joint member 100 (fig. 10), or as modification 5, may be formed by reducing the diameter of the end portion of the joint member 100 where the connection auxiliary portion 200 is provided from the other portion to protrude inward from the inner peripheral surface 100a of the joint member 100 (fig. 11 and 12). With this configuration, the amount of insertion of the refrigerant pipe (joint member) to be connected can be easily limited, and sagging of the brazing filler metal used for brazing can be prevented. Further, since the pipe stopper 101 can be integrally formed with the joint member 100, it is not necessary to separately provide the pipe stopper 101, and the number of parts can be suppressed.

In this case, as in modification 6 shown in fig. 13, it is preferable that a flange 203 bent radially inward is provided at a portion of the connection auxiliary portion 200 that is disposed at the opening-side end portion (end surface 100 c) of the joint member 100. Thus, when the connection auxiliary portion 200 is arranged in the opening end portion of the joint member 100 in a state of being bent in a C-shape, the flange portion 203 faces the end surface 100C of the joint member 100, and the connection auxiliary portion 200 can be easily positioned with respect to the opening end portion. Further, since the melt-solidified layer 300 of the brazing filler metal is formed between the flange 203 and the end face 100c of the joint member 100, the connection auxiliary 200 extending to the end face 100c of the joint member 100 can be easily provided, and the reliability of connection can be more easily ensured.

In the joint member 100 having the connection auxiliary portion 200 joined by brazing in the same manner as described above, even when the refrigerant pipe 60 connected to the outer peripheral surface 100b side of the joint member 100 is made of copper or copper alloy as shown in fig. 14 in which the same reference numerals are given to the corresponding portions in fig. 7, the connection can be easily made by brazing. At this time, since the connection auxiliary portion 200 of phosphor bronze having the flange portion 203 extending to the end face 100c of the joint member 100 is provided in addition to the face (in this case, the outer peripheral face 100 b) that contacts the inner peripheral face 60b of the refrigerant pipe 60 of the joint member 100, when the material of the refrigerant pipe 60 is copper or copper alloy that is the same as that of the connection auxiliary portion 200, the first round corner 70 for satisfactorily joining the refrigerant pipe 60 is easily formed. This ensures that the brazing portions are bonded with no gap therebetween, and that the brazing portions are reliably airtight. Therefore, the reliability of the connection between the joint member 100 and the refrigerant pipe 60 can be further improved. Further, the end face 60c side of the refrigerant pipe 60 is in contact with the pipe stopper 101, whereby the amount of insertion of the refrigerant pipe 60 into the joint member 100 can be easily restricted, and sagging of the brazing filler metal used for brazing can be prevented. In addition, when the material of the refrigerant pipe 60 is copper or copper alloy similar to that of the connection auxiliary portion 200, the second rounded corner 80 for satisfactorily joining the refrigerant pipe 60 is easily formed between the end surface 60c side of the refrigerant pipe 60 and the connection auxiliary portion 200. This ensures that the joint member 100 is joined without gaps, and the gas tightness of the soldered portion can be reliably ensured, thereby further improving the reliability of the connection between the joint member and the refrigerant pipe 60.

Next, a case will be described in which the connection auxiliary portions 200 are provided on both surfaces of the inner peripheral surface 100a and the outer peripheral surface 100b of the joint member 100. As in the modifications 7 and 8 shown in fig. 15 and 16, in which the same reference numerals are given to the corresponding parts in fig. 2 and 4, the connection auxiliary portion 200 may have a U-shaped cross section, and one end of the joint member 100 may be inserted into the inner peripheral side of the U-shaped cross section from the end face 100 c. In this case, the connection assisting portion 200 is provided from the inner peripheral surface 100a of the joint member 100 to the outer peripheral surface 100b via the end surface 100 c.

In this way, when the connection auxiliary portion 200 is provided over the range from the inner peripheral surface 100a to the outer peripheral surface 100b of the joint member 100, the connection auxiliary portion 200 is also formed over the range substantially equal to the length of the joint member 100 inserted into the refrigerant pipe 60 (see fig. 7 and 14). Specifically, the brazing strength of the refrigerant pipe connected to the joint member 100 is sufficiently set in a range that extends from the end surface of the joint member 100 to at least a length equal to or longer than the wall thickness of the joint member 100, preferably to at least a length equal to or longer than half the inner diameter of the joint member 100, and more preferably to at least a length equal to or longer than the inner diameter of the joint member 100. In the joint member 100 shown in fig. 10 to 14, the pipe stopper 101 is formed so that the protruding amount thereof protrudes outward from the outer peripheral surface of the connection auxiliary 200. That is, the pipe stopper 101 is formed to have an outer diameter larger than that of the connection auxiliary portion 200. On the other hand, in the joint member 100 shown in fig. 15 and 16, the pipe stopper 101 is formed so that its protruding amount protrudes inward from the inner peripheral surface of the connection auxiliary portion 200. That is, the pipe stopper 101 is formed to have an inner diameter smaller than that of the connection auxiliary 200.

According to such a configuration, not only the outer peripheral surface 100b and the inner peripheral surface 100a of the end portion of the joint member 100 but also the connection auxiliary portion 200 integrally covering the end surface 100c of the joint member 100 can be easily provided, and therefore, when the material of the connection object is the same copper or copper alloy as that of the connection auxiliary portion 200, the rounded corners can be easily formed. Accordingly, the joint member 100 and the connecting object are joined without any gap, the air tightness of the soldered portion can be reliably ensured, and a structure that can further ensure the reliability of the connection can be easily realized.

Further, the description will be made of the case where the pipe stopper 101 that restricts the insertion amount of the other refrigerant pipe to be connected is formed at the portion where the inner end portion of the connection auxiliary portion 200 in the longitudinal direction of the joint member 100 is located up to this point, but the present invention is not limited to this. That is, as in modification 9 and modification 10 shown in fig. 17 and 18, a pipe stopper 205 that restricts the amount of insertion of another refrigerant pipe to be connected may be formed at the inner end portion in the longitudinal direction of the connection auxiliary portion 200 in the state of being provided in the joint member 100. With this configuration, the amount of insertion of the refrigerant pipe (joint member) to be connected can be easily limited, and sagging of the brazing filler metal used for brazing can be prevented.

At this time, the pipe stopper 205 preferably protrudes outward from the outer peripheral surface 100b of the connection auxiliary portion 200 or inward from the inner peripheral surface 100a, or both. According to this configuration, the pipe stopper 205 and the connection auxiliary portion 200 can be integrally formed, so that the pipe stopper 205 and the connection auxiliary portion 200 do not need to be provided separately, and the number of parts can be suppressed.

In the present embodiment, the description has been made of the case where the joint member 100 as the refrigerant pipe is connected to the refrigerant pipe 60 made of copper or copper alloy in the refrigeration cycle, but the connection object of the joint member 100 is not limited to the refrigerant pipe made of copper or copper alloy, and may be a pipe or joint member made of metal such as stainless steel, iron, or the like, having the connection auxiliary portion 200 made of copper or copper alloy on the inner peripheral surface, the outer peripheral surface, or both surfaces of the connection side end portions, as in the case of the joint member 100. As a material of the refrigerant piping having the connection auxiliary portion 200, a metal having a higher melting point than copper or copper alloy is preferable. In the present embodiment, the description has been made of copper or a copper alloy as the material of the connection support portion 200 provided in the joint member 100 as the refrigerant pipe, but the material (second metal material) of the connection support portion 200 may be the same as or the same as the material (second metal material) of the refrigerant pipe 60. For example, in the case where the material of the refrigerant pipe 60 is aluminum (second metal material), a connection auxiliary portion made of aluminum (second metal material) may be provided in the stainless steel refrigerant pipe 60. That is, the material provided on the joint member 100 may be the same as the surface of the refrigerant pipe 60 on the joint member 100 side.

As described above, the connection structure of the refrigerant pipe (joint member 100) is a connection structure of the joint member 100 in which the joint member 100 (first refrigerant pipe) and the refrigerant pipe 60 (second refrigerant pipe) are connected by brazing, and it is preferable that the joint member 100 made of stainless steel has the connection auxiliary portion 200 of copper or copper alloy joined by brazing on the inner peripheral surface 100a (or the outer peripheral surface 100 b) of the end portion on the side of the refrigerant pipe 60, and the refrigerant pipe 60 is made of copper or copper alloy (or the connection auxiliary portion 200 of copper or copper alloy joined by brazing is provided on the outer peripheral surface 100b or the inner peripheral surface 100a of the end portion on the side of the joint member 100). According to the connection structure of the joint member 100, even in the case where the joint member 100 (first refrigerant pipe) is made of stainless steel, since the connection auxiliary portion 200 of copper or copper alloy is provided in the inner peripheral surface 100a or the outer peripheral surface 100b which is brazed to the end portion on the side of the refrigerant pipe 60 (second refrigerant pipe), the second refrigerant pipe which is made of copper or copper alloy as a connection target or which is provided in the connection auxiliary portion of copper or copper alloy which is brazed to the outer peripheral surface 60a or the inner peripheral surface 60b on the side of the first refrigerant pipe can be easily connected by brazing.

As described above, the sliding type switching valve 10 of the valve device is a valve device in which the joint member 11 is connected to the valve housing 1 as the valve body, and it is preferable to use any one of the refrigerant pipes (joint member 100) as the joint member. According to the sliding type switching valve 10, even in the case where the joint member 100 is made of stainless steel, the joint member 100 is provided with the copper or copper alloy connection auxiliary portion 200 welded to the inner peripheral surface 100a or the outer peripheral surface 100b at the connecting side end portion thereof, and therefore, the connection to the refrigerant pipe to be connected can be easily performed by brazing. In addition, the same effects as those of each joint member 100 described above can be obtained.

In the above description, the best configuration, method, and the like for carrying out the present invention are disclosed, but the present invention is not limited thereto. That is, the present invention has been specifically illustrated and described mainly for specific embodiments, but the present invention is not limited to the scope of the technical idea and the object of the present invention. For example, in the above-described embodiment, the case where the refrigerant pipe of the present invention is applied to the sliding type switching valve has been described, but the refrigerant pipe of the present invention is not limited to the sliding type switching valve, and can be applied to various kinds of devices such as a motor-operated valve, a solenoid valve, a check valve, and the like, as well as various kinds of devices such as a heat exchanger, a liquid reservoir, an oil separator, and a compressor. In addition, in the above-described embodiments, various modifications can be made by those skilled in the art in terms of shape, material, number, and other detailed structures. Therefore, the description of the above-disclosed shapes, materials, and the like is illustrative for easy understanding of the present invention, and is not intended to limit the present invention, and therefore, the description in the names of some or all of the limited components of the above-described shapes, materials, and the like is included in the present invention.

Claims (20)

1. A refrigerant piping made of stainless steel, characterized in that,

at least one end portion in the longitudinal direction is provided with a thin plate-like connection auxiliary portion made of copper or copper alloy on the inner peripheral surface, the outer peripheral surface or both surfaces,

a molten solidified layer of solder is formed between the inner peripheral surface, the outer peripheral surface, or both and the connection auxiliary portion.

2. The refrigerant piping according to claim 1, wherein,

the connection auxiliary member is disposed so as to be pressed by an inner peripheral surface, an outer peripheral surface, or both of the refrigerant piping.

3. The refrigerant piping according to claim 1, wherein,

the connection auxiliary portion is arranged in a state of being bent in a C-shape when viewed from a direction orthogonal to the axial direction.

4. The refrigerant piping according to claim 1, wherein,

the connection auxiliary portion is an annular cylindrical body.

5. The refrigerant piping according to claim 1, wherein,

the connection auxiliary portion is provided to extend to an end face of the one end portion.

6. The refrigerant piping according to claim 5, wherein,

the connection auxiliary portion has a flange portion facing the end face, and a melt-solidified layer of solder is formed between the flange portion and the end face.

7. The refrigerant piping according to claim 1, wherein,

the connection auxiliary portion has a U-shaped cross section, and the one end portion is inserted into the inner peripheral side of the U-shaped cross section.

8. The refrigerant piping according to claim 1, wherein,

a pipe stopper is formed at a portion of the refrigerant pipe where an inner end of the connection auxiliary portion in the longitudinal direction is located, and the pipe stopper restricts an insertion amount of another refrigerant pipe to be connected.

9. The refrigerant piping according to claim 8, wherein,

the pipe stopper protrudes outward from the outer peripheral surface of the refrigerant pipe or inward from the inner peripheral surface.

10. The refrigerant piping according to claim 1, wherein,

a pipe stopper is formed at an inner end portion of the connection auxiliary portion in the longitudinal direction in a state of being provided in the refrigerant pipe, and the pipe stopper restricts an insertion amount of another refrigerant pipe to be connected.

11. The refrigerant piping according to claim 10, wherein,

the pipe stopper protrudes outward from the outer peripheral surface of the connection auxiliary portion, inward from the inner peripheral surface, or both.

12. The refrigerant piping according to claim 1, wherein,

the connection auxiliary portion has a thickness smaller than that of the refrigerant pipe.

13. The refrigerant piping according to claim 1, wherein,

the thickness of the melt-solidified layer is thinner than the thickness of the connection auxiliary portion.

14. A refrigerant piping connection structure for connecting a first refrigerant piping and a second refrigerant piping by brazing, characterized in that,

the first refrigerant pipe is made of stainless steel, and a thin plate-shaped connection auxiliary part made of a second metal material different from stainless steel is bonded to the inner peripheral surface, the outer peripheral surface or both surfaces of the second refrigerant pipe side end part via a melt-solidified layer of brazing filler metal,

the second refrigerant pipe is made of the second metal material, or a thin plate-shaped connection auxiliary portion using the second metal material is joined to the outer peripheral surface, the inner peripheral surface, or both of the first refrigerant pipe side end portions via a melt-solidified layer of the brazing material.

15. The refrigerant piping connection structure according to claim 14, wherein,

The connection auxiliary portion is formed to extend to an end face of the second refrigerant pipe at the first refrigerant pipe side end portion, in a case where the end face of the second refrigerant pipe at the second refrigerant pipe side end portion and the second refrigerant pipe are not made of the second metal material.

16. The refrigerant piping connection structure according to claim 14, wherein,

the connection auxiliary portion is provided so as to extend to an end surface of the second refrigerant pipe side end portion of the first refrigerant pipe.

17. The refrigerant piping connection structure according to claim 16, wherein,

the connection auxiliary portion has a flange portion facing the end face, and a melt-solidified layer of solder is formed between the flange portion and the end face.

18. The refrigerant piping connection structure according to claim 14, wherein,

the connection auxiliary portion has a thickness smaller than that of the first refrigerant pipe.

19. The refrigerant piping connection structure according to claim 14, wherein,

the thickness of the melt-solidified layer is thinner than the thickness of the connection auxiliary portion.

20. A valve device in which a joint member is connected to a valve body, characterized in that,

Use of the refrigerant piping as claimed in any one of claims 1 to 13 as the joint member.