VALVE DEVICE AND REFRIGERATION CYCLE SYSTEM

Abstract

Valve device comprising a device main body (11) and a connecting pipe (14), characterized in that that in the connecting pipe (14), a stainless steel pipe (141) and an aluminum pipe (142) are connected in such a way that their axial line directions (D11) coincide with each other, that one end of the stainless steel tube (141) is connected to a stainless steel valve main body (111-1) of the device main body (11) and the other end of the stainless steel tube (141) is connected to the aluminum tube (142), that the stainless steel tube (141) and the aluminum tube (142) are connected by soldering by means of a soldering material (143a) and a soldering material section (143) is formed between the stainless steel tube (141) and the aluminum tube (142), that a load-bearing portion (144, 244, 344, 444) for receiving a load in the axial line direction (D11) is provided on a connecting surface of the stainless steel tube (141) and the brazing material portion (143), and that the load-bearing portion (144, 244, 344, 444) is formed by a load-bearing groove (344a, 444a) recessed in a diameter direction (D12) starting from a stainless steel side connecting surface (141a) of the connecting surface, wherein the stainless steel side connecting surface (141a) is a surface on the side of the stainless steel pipe (141), and the brazing material portion (143) is provided penetrating into the load-bearing groove (344a, 444a).

Description

[Technical field]

[0001] The present invention relates to a valve device and a refrigeration cycle system. [Background technology]

[0002] Conventionally, a refrigerant device in which a refrigerant discharge pipe and a refrigerant intake pipe are connected to a device main body (see, for example, Patent Document 1) is used as a device constituting an air conditioner (refrigeration cycle system, freezer), etc. In some cases, a connecting pipe in which two pipes are connected together is used as a pipe in this device.

[0003] Influenced by rising material costs, etc., the material used to make the device's main body and various types of pipes has been changing in recent years from copper to inexpensive stainless steel and aluminum. In some cases, the device's main body, etc., requiring a certain degree of strength, is made of stainless steel, while some pipes are made of aluminum due to its ease of machining.

[0004] The subsequently published patent application DE 10 2023 116 871 A1 discloses a device main body to which an aluminum coolant line is directly attached. General socket connections for connecting two pipes are known from DE 195 21 583 A1, US 2018 / 0 313 475 A1, and DE 10 2004 038 099 A1. [Citation list][Patent document]

[0005] [Patent Document 1] Patent Publication No. JP 2004 - 125 238 A [Overview of the invention][Technical problem]

[0006] In general, brazing with aluminum is difficult. In particular, brazing with stainless steel is difficult, and this can lead to unstable joint strength. At the joining surface of stainless steel and aluminum, an intermetallic compound is formed between the brazing material for aluminum and stainless steel. While the interface between the brazing material for aluminum and aluminum is alloyed, thus achieving high joint strength, the intermetallic compound formed at the joining surface with the stainless steel has hard and brittle properties, so the adhesion to the stainless steel is not very strong. These properties of the intermetallic compound at the joining surface with the stainless steel are a factor that leads to difficulty in brazing and unstable joint strength.In this case, as a pipe connected to a stainless steel device main body, a stainless steel pipe is often used for the connecting pipe as shown above, achieving high joint strength by using a stainless steel brazing material. On the other hand, an easily machined aluminum pipe is sometimes used for a pipe on the device side that is to be routed to the coolant device with different shaped piping paths. Regarding the brazing joint between the stainless steel pipe and the aluminum pipe in this connecting pipe, this could cause difficulty in brazing and instability in the joint strength. Therefore, in the current situation, high quality control is required to maintain the joint strength.

[0007] The purpose of the present invention is to provide a joint pipe, an apparatus, and a refrigeration cycle system in which the joint strength can be increased with respect to the brazing joint of a stainless steel pipe and an aluminum pipe. [Means of solving the problem]

[0008] The invention relates to a valve device according to claim 1 and a valve device according to claim 3. Furthermore, the invention relates to a refrigeration cycle system according to claim 7. The dependent claims relate to advantageous developments of the invention.

[0009] The connecting pipe of the present invention is a connecting pipe in which a stainless steel pipe and an aluminum pipe are connected such that their axial line directions coincide with each other, characterized in that the stainless steel pipe and the aluminum pipe are connected by brazing using a brazing material, and a brazing material portion is formed between the stainless steel pipe and the aluminum pipe, and a load receiving portion for receiving a stress load in the axial line direction is provided on a connecting surface of the stainless steel pipe and the brazing material portion.

[0010] According to this joint pipe, the load-bearing portion provided at the joint surface of the stainless steel pipe and the brazing material portion can absorb the stress load in a shear direction (i.e., in the axial direction) that tends to cause the intermetallic compound to detach from the joint surface. This absorption then suppresses the above stress load from directly acting on the intermetallic compound, thus suppressing the intermetallic compound from detaching, and thus resisting the forces in the axial direction of the aluminum pipe. That is, according to the above joint pipe, the joint strength with respect to the brazing joint of the stainless steel pipe and the aluminum pipe can be increased.

[0011] It is preferred that the load-bearing portion is formed by a load-bearing groove recessed in a diameter direction starting from a stainless steel side connecting surface of the connecting surface, wherein the stainless steel side connecting surface is a surface on the side of the stainless steel pipe, and the brazing material portion is provided penetrating into the load-bearing groove.

[0012] According to this structure, by a simple structure such as the penetration of the brazing material into the load-bearing groove by which the load-bearing portion is formed, the loading load in the axial line direction can be efficiently absorbed, so that peeling of the intermetallic compound can be further suppressed.

[0013] Further, it is preferable that a plurality of the load-bearing grooves are provided side by side in the axial line direction or are provided in a spiral order.

[0014] According to this structure, in the joining surface in the cross-sectional area of ​​the axial line direction, a plurality of recesses are adjacent to each other in the axial line direction, so that by penetrating the solder material into these plurality of recesses, the stress load in the axial line direction can be absorbed more efficiently and detachment of the intermetallic compound can be further suppressed.

[0015] Further, it is preferable that the load-bearing portion is formed by a projecting load-bearing portion that projects in a diameter direction of the stainless steel pipe from a stainless steel side joining surface of the joining surface, the stainless steel side joining surface being a surface on the side of the stainless steel pipe, and the projecting load-bearing portion is provided penetrating into the brazing material portion.

[0016] According to this structure, by a simple structure such as penetrating the projecting load receiving portion by which the load receiving portion is formed into the brazing material portion, the stress load in the axial line direction can be efficiently absorbed, so that peeling of the intermetallic compound can be further suppressed.

[0017] Further, it is preferable that the load-bearing portion has a load-bearing inclination surface inclined toward a stainless steel side connecting surface of the connecting surface, wherein the stainless steel side connecting surface is a surface on the side of the stainless steel pipe.

[0018] According to this structure, the load-bearing slope surface at the load-bearing portion can widely absorb the load in the axial line direction and largely suppress the peeling of the intermetallic compound, so that the joint strength with respect to the solder joint can be further increased.

[0019] Further, it is preferable that a dimension of the load-bearing portion in the axial line direction is larger than a layer thickness of an intermetallic compound formed between a stainless steel side joining surface of the joining surface, the stainless steel side joining surface being a surface on the side of the stainless steel pipe, and the brazing material.

[0020] According to this structure, the dimension of the load-bearing portion in the axial direction is larger than the layer thickness of the intermetallic compound, so that the shear load (i.e., the axial direction), which may tend to cause the intermetallic compound to detach from the bonding surface, can be absorbed over a sufficient length in the axial direction. This absorption effectively prevents the above stress load from directly acting on the intermetallic compound.

[0021] Further, it is preferable that a dimension of the load-bearing portion in a crossing direction crossing the axial line direction is larger than a layer thickness of an intermetallic compound formed between a stainless steel side joining surface of the joining surface, the stainless steel side joining surface being a surface on the side of the stainless steel pipe, and the brazing material.

[0022] According to this structure, the stress load in the shear direction (ie, in the axial line direction) can be absorbed over a sufficient length in the above crossing direction, and also by this absorption, the above stress load can be efficiently suppressed from directly acting on the intermetallic compound.

[0023] Further, in the stainless steel pipe and the aluminum pipe, it is preferable that the inner diameter of one pipe is larger than the outer diameter of the other pipe, the other pipe is inserted into the one pipe by a certain length, and the brazing material portion is formed in a substantially cylindrical shape between the outer peripheral surface of the other pipe and the inner peripheral surface of the one pipe.

[0024] According to this structure, the brazing material portion between the stainless steel pipe and the aluminum pipe, which connects the two pipes, is formed into a substantially cylindrical shape, so that the stress direction on the intermetallic joint at the joint surface of the stainless steel pipe is almost in the shear direction (i.e., the axial line direction). Since the stress direction is almost in the shear direction (i.e., the axial line direction), the reduction in the strength of the intermetallic joint can be suppressed and the joint strength can be further increased.

[0025] Further, in the stainless steel pipe and the aluminum pipe, it is preferable that the inner diameter of one pipe is larger than the outer diameter of the other pipe, the other pipe is inserted into the one pipe by a certain length, and an insertion end of the other pipe inserted into the one pipe and a receiving end of the one pipe receiving the insertion end inside each have a substantially cylindrical shape in which the diametrical dimensions in the axial line direction are unchanged.

[0026] According to this structure, the brazing material portion between the substantially cylindrical male end and the female end is formed into a substantially cylindrical shape, so that the stress direction on the intermetallic compound at the joint surface of the stainless steel pipe is almost the shear direction (i.e., the axial line direction). Since the stress direction is almost the shear direction (i.e., the axial line direction), the reduction in the strength of the intermetallic compound can be suppressed and the joint strength can be further increased.

[0027] Further, the device of the present invention is characterized by including the connecting pipe described above.

[0028] According to this device, its connecting pipe is the connecting pipe described above, so that the connection strength can be increased regarding the soldering point of the stainless steel pipe and the aluminum pipe in the connecting pipe.

[0029] Further, the refrigeration cycle system of the present invention is characterized by including the device described above.

[0030] According to this refrigeration cycle system, the device described above is included, so that the connection strength regarding the soldering point of the stainless steel pipe and the aluminum pipe in the device can be increased. [Effects of the invention]

[0031] According to the connecting pipe, the apparatus and the refrigeration cycle system of the present invention, the connection strength with respect to the brazing joint of the stainless steel pipe and the aluminum pipe can be increased. [Brief explanation of the figures] [ Fig. 1] Fig. 1 is a partial cross-sectional view showing an electrically operated valve which is a first embodiment of a connecting pipe-including apparatus; [ Fig. 2] Fig. 2 is a schematic view showing a refrigeration cycle system using the Fig. 1 shown electrically operated valve; [ Fig. 3] Fig. 3 is an enlarged view of a wall section comprising a first area A11 and a second area A12 in Fig. 1, which have a common structure; [ Fig. 4] Fig. Fig. 4 is a view showing a load receiving portion in a second embodiment at the same enlarged cross-sectional area as in Fig. 3 shows; [ Fig. 5] Fig. Fig. 5 is a view showing a load receiving portion in a third embodiment at the same enlarged cross-sectional area as in Fig. 3(A) and Fig. 4(A) shows; and [ Fig. 6] Fig. Fig. 6 is a view showing a load receiving portion in a fourth embodiment at the same enlarged cross-sectional area as in Fig. 5 shows. [Forms for carrying out the invention]

[0032] In the following, a first embodiment of a connecting pipe, a device and a refrigeration cycle system based on Fig. 1 to Fig. 3 described.

[0033] Fig. 1 is a partial cross-sectional view showing an electrically operated valve which is a first embodiment of a connecting pipe-comprising device, and Fig. 2 is a schematic view showing a refrigeration cycle system using the Fig. 1 shown electrically operated valve. Furthermore, Fig. 3 is an enlarged view of a wall section comprising a first area A11 and a second area A12 in Fig. 1, which have a common structure.

[0034] An electrically operated valve 10 of the present embodiment is used in a Fig. 2 as an expansion valve 100 described later. The electrically operated valve 10 includes a device main body 11, a first connecting pipe 12, and a second connecting pipe 13. The electrically operated valve 10 is a device in which a valve body 11b is moved forward and backward within a valve chamber 11a by a motor drive with respect to a valve seat component 11c, so that the flow rate of a refrigerant flowing between the first connecting pipe 12 and the second connecting pipe 13 is adjusted via the valve chamber 11a. The device main body 11 includes a valve main body 111-1, inside which the valve chamber 11a is formed, and a housing 111-2 in which a forward and backward mechanism of the valve body 11b is installed.The housing 111-2 is welded to the valve main body 111-1, thereby forming a cylindrical housing 111 of the device main body 11, closed at both ends. One end of the first connecting pipe 12 is connected to a bottom wall portion 111a of the valve chamber 11a of the valve main body 111-1 of the device main body 11 by brazing, so that the first connecting pipe 12 extends along a valve axis X1. Further, one end of the second connecting pipe 13 is connected to a surrounding wall portion 111b of the valve chamber 11a of the valve main body 111-1 by brazing, so that the second connecting pipe 13 extends orthogonally to the valve axis X1. In the present embodiment, the first connecting pipe 12 and the second connecting pipe 13 have the same structure as each other.In the following, the first connecting pipe 12 and the second connecting pipe 13 are simply referred to as the connecting pipe 14, with the terms “first” and “second” being omitted.

[0035] The connecting pipe 14 is a connecting pipe in which a cylindrical stainless steel pipe 141 and an aluminum pipe 142 are connected in the axial line direction D11 along a mutually coaxial pipe axis X2 (that is, the connecting pipe 14 is a connecting pipe in which the stainless steel pipe 141 and the aluminum pipe 142 are connected such that their axial line directions coincide with each other). On the other hand, the valve main body 111-1 of the device main body 11, to which the connecting pipe 14 is connected, is a stainless steel portion. One end of the stainless steel pipe 141 of the connecting pipe 14 is then connected to the stainless steel valve main body 111-1 by brazing using a brazing material for stainless steel. On the other hand, the connection of the stainless steel pipe 141 and the aluminum pipe 142 in the connecting pipe 14 is performed by brazing using a brazing material for aluminum.The brazing structure using this brazing material at the connecting pipe 14 will be described later based on . Fig. 3 described in detail.

[0036] First, prior to the description of the soldering structure in the electrically operated valve 10, an overview of the refrigeration cycle system 1 for circulating refrigerant, which includes the electrically operated valve 10 as the expansion valve 100, will be given based on Fig. 2. The refrigeration cycle system 1 of the present embodiment includes the expansion valve 100, a heat exchanger outdoor unit 200, a heat exchanger indoor unit 300, a flow path switching valve 400, and a compressor 500, each of which is connected via piping as shown, forming a heat pump refrigeration cycle. Illustrations of an accumulator, pressure sensor, temperature sensor, etc. are omitted.

[0037] The flow path of the refrigeration cycle is switched by the flow path switching valve 400 in two ways, namely, a flow path during cooling operation and a flow path during heating operation. During cooling operation, as in Fig. 2, a refrigerant compressed by the compressor 500 flows from the flow path switching valve 400 into the heat exchanger outdoor unit 200. The heat exchanger outdoor unit 200 functions as a condenser, and liquid refrigerant discharged from the heat exchanger outdoor unit 200 flows into the heat exchanger indoor unit 300 via the expansion valve 100, with the heat exchanger indoor unit 300 functioning as an evaporator.

[0038] During heating operation, on the other hand, the air circulates as in Fig. 2, a refrigerant compressed by the compressor 500 flows from the flow path switching valve 400 in sequence through the heat exchanger indoor unit 300, the expansion valve 100, the heat exchanger outdoor unit 200, the flow path switching valve 400, and the compressor 500. The heat exchanger indoor unit 300 functions as a condenser, and the heat exchanger outdoor unit 200 functions as an evaporator. The expansion valve 100 decompresses and expands the liquid refrigerant flowing in from the heat exchanger outdoor unit 200 during cooling operation or the liquid refrigerant flowing in from the heat exchanger indoor unit 300 during heating operation, and further controls the flow rate of this refrigerant. Fig. 2, the expansion valve 100 is provided such that, during cooling operation, liquid refrigerant flows from the heat exchanger outdoor unit 200 into a second pipe 102 (the second connecting pipe 13), and during heating operation, liquid refrigerant flows from the heat exchanger indoor unit 300 into a first pipe 101 (the first connecting pipe 12). However, this is not limited to this, so the expansion valve 100 can also be provided such that, during cooling operation, liquid refrigerant flows from the heat exchanger outdoor unit 200 into the first pipe 101, and, during heating operation, liquid refrigerant flows from the heat exchanger indoor unit 300 into the second pipe 102.

[0039] Next, also based on Fig. 3 the soldering structure of the stainless steel tube 141 and the aluminum tube 142 in Fig. 1 shown connecting pipe 14. Fig. 3 shows the soldering structure at the connecting pipe 14 as an enlarged view, which is used for the first area A11 and second area A12 in Fig. 1 is common. Regarding Fig. 3 is in Fig. 3(A) is an enlarged view, and in Fig. 3(B) shows a cross-sectional area of ​​a connecting end of the stainless steel pipe 141 along the pipe axis X2.

[0040] In the present embodiment, the stainless steel tube 141 and the aluminum tube 142, as shown in Fig. 1 and Fig. 3, in the connecting portion, an inner diameter φB of the aluminum tube 142 (one tube) is larger than an outer diameter φA of the stainless steel tube 141 (the other tube). The stainless steel tube 141 and the aluminum tube 142 are cylindrical tubes, and the diameter of the aluminum tube 142 is enlarged such that the aluminum tube 142 has the projecting inner diameter φB in the connecting portion with the stainless steel tube 141. The stainless steel tube 141 is inserted into the enlarged diameter portion of the aluminum tube 142 by a certain insertion length L11. The projecting diameter increase of the aluminum tube 142 occurs in the axial line direction D11 over the insertion length L11. The stainless steel tube 141 is inserted up to a step portion 142a-1 formed by increasing the diameter of an inner surface 142a of the aluminum tube 142 at a position away from the opening by the insertion length L11.

[0041] The connection of the pipes to each other is not limited to the case where the diameter of one pipe is enlarged and the other pipe is inserted into the enlarged-diameter portion, as in the present embodiment. For example, unlike the present embodiment, the diameter of one pipe may be reduced and the reduced-diameter portion may be inserted into the other pipe. Alternatively, two types of pipes with originally different pipe diameters may be prepared, and the small-diameter pipe may be inserted into the large-diameter pipe. In this case, the insertion depth location can be adjusted by punching inside or outside the pipe, etc.

[0042] In the present embodiment, an insertion end 141-1 of the stainless steel tube 141 and a receiving end 142-1 of the aluminum tube 142 each have a substantially cylindrical shape in which the diametrical dimensions in the axial line direction D11 are unchanged. The insertion end 141-1 is a portion of the stainless steel tube 141 that has been inserted into the aluminum tube 142. Further, the receiving end 142-1 is a portion of the aluminum tube 142 that receives the insertion end 141-1 inside. As a result of brazing using a brazing material 143a for aluminum, a brazing material portion 143 is formed between the insertion end 141-1 of the stainless steel tube 141 and the receiving end 142-1 of the aluminum tube 142. The brazing material portion 143 is formed in a substantially cylindrical shape over the insertion length L11.

[0043] Then, a load-bearing portion 144 for receiving a load F11 in the axial line direction D11 is provided on the joining surface of the stainless steel pipe 141 and the brazing material portion 143. The load-bearing portion 144 in the present embodiment is formed by a projecting load-bearing portion 144a that projects in a diametrical direction D12 of the stainless steel pipe 141 from a stainless steel side joining surface 141a of the joining surface, where the stainless steel side joining surface 141a is a surface on the side of the stainless steel pipe 141. The projecting load-bearing portion 144a of the present embodiment has a curved projecting shape in which the outer surface projects to form part of a spherical surface. This projecting load-bearing portion 144a is provided penetrating into the brazing material portion 143.The projecting load-bearing portion 144a is formed by projecting the stainless steel pipe 141 from the inside to the outside, and a recess 141c is formed at a position on an inner surface 141b of the stainless steel pipe 141 corresponding to the projecting load-bearing portion 144a. Furthermore, in the present embodiment, the four projecting load-bearing portions 144a are arranged at a pitch of 90° in a circumferential direction D13. The load-bearing portion 144 including these four projecting load-bearing portions 144a then receives the stress load F11 in the axial line direction D11 by the respective projecting load-bearing portions 144a penetrating into the brazing material portion 143. In . Fig. 3(B) is the projecting load-bearing portion 144a penetrating into the brazing material portion 143, which, due to its too small size, is Fig. 1 is not shown, is shown with greater emphasis.

[0044] A projection width dimension W11 of each projecting load-bearing portion 144a of the load-bearing portion 144 in the axial line direction D11 is greater than a layer thickness t11 of an intermetallic compound 145 formed between the stainless steel side joining surface 141a and the aluminum brazing material 143a. Described in more detail, the projection width dimension W11 is greater than twice the layer thickness t11 of the intermetallic compound 145.

[0045] The layer thickness t11 of the intermetallic compound 145 is affected by the brazing temperature and heating time, so the specific numerical values ​​vary, but generally range from a few to tens of µm. This value generally corresponds to a thickness of approximately 3 to 25% of a clearance t12 between the stainless steel side joining surface 141a and the aluminum tube 142 when no brazing material 143a is present. The clearance t12 represents the thickness of the brazing material 143a between a portion of the stainless steel side joining surface 141a where no protruding load-bearing portion 144a is formed and the aluminum tube 142.

[0046] Furthermore, a projection height dimension W12 of each projecting load-bearing portion 144a of the load-bearing portion 144 in the crossing direction crossing the axial line direction D11, namely, in the diameter direction D12, is larger than the layer thickness t11 of the intermetallic compound 145. Regarding the projection height dimension W12, in more detail, the projection height dimension W12 is larger than the single layer thickness t11 of the intermetallic compound 145. Furthermore, the projection height dimension W12 is larger than the clearance t12 between the stainless steel side joint surface 141a and the aluminum tube 142.

[0047] In the first embodiment described above, according to the connecting pipe 14, the electrically operated valve 10 as an example of a device, and the refrigeration cycle system 1 including the electrically operated valve 10 as the expansion valve 100, the following effects can be achieved. That is, according to the present embodiment, the load receiving portion 144 provided at the joint surface of the stainless steel pipe 141 and the brazing material portion 143 can absorb the stress load F11 in the shear direction (ie, in the axial line direction D11), which may tend to cause the intermetallic compound 145 to peel off from the joint surface.By this absorption, the above stress load F11 is suppressed from directly acting on the intermetallic compound 145, so that peeling of the intermetallic compound 145 is suppressed, thereby resisting the forces in the axial line direction D11 of the aluminum tube 142. That is, according to the present embodiment, the joining strength with respect to the brazing joint of the stainless steel tube 141 and the aluminum tube 142 can be increased.

[0048] In the present embodiment, the load-bearing portion 144 is formed by the protruding load-bearing portion 144a protruding in the diametrical direction D12 from the stainless steel side joining surface 141a, and the protruding load-bearing portion 144a is provided penetrating into the brazing material portion 143. According to this configuration, by a simple configuration such as penetrating the protruding load-bearing portion 144a, by which the load-bearing portion 144 is formed, into the brazing material portion 143, the stress load F11 in the axial line direction D11 can be efficiently absorbed, so that peeling of the intermetallic compound 145 can be further suppressed.

[0049] Furthermore, in the present embodiment, the projection width dimension W11 of the projecting load-bearing portion 144a, by which the load-bearing portion 144 is formed, in the axial line direction D11 is larger than the layer thickness t11 of the intermetallic compound 145. According to this structure, the stress load F11 in the shear direction (i.e., in the axial line direction D11), which may tend to cause peeling of the intermetallic compound 145, can be absorbed over a sufficient length in the axial line direction D11. This absorption can then effectively suppress the projecting stress load F11 from directly acting on the intermetallic compound 145.

[0050] Further, in the present embodiment, the protrusion height dimension W12 of the protruding load receiving portion 144a in the diameter direction D12 is larger than the layer thickness t11 of the intermetallic compound 145. According to this structure, the stress load F11 in the shear direction (ie, in the axial line direction D11) can be absorbed over a sufficient length in the diameter direction D12, and also by this absorption, the protruding stress load F11 can be efficiently suppressed from directly acting on the intermetallic compound 145.

[0051] Furthermore, in the present embodiment, the inner diameter φB of the aluminum tube 142 is larger than the outer diameter φA of the stainless steel tube 141. The stainless steel tube 141 is then inserted into the aluminum tube 142 by the insertion length L11, and the brazing material portion 143 is formed in a substantially cylindrical shape between the outer peripheral surface of the stainless steel tube 141 and the inner peripheral surface of the aluminum tube 142. According to this structure, the brazing material portion 143, which is located between the stainless steel tube 141 and the aluminum tube 142 and connects the two tubes, is formed in a substantially cylindrical shape, so that the stress direction on the intermetallic compound 145 is almost the shear direction (ie, the axial line direction D11). Since the stress direction is almost the shear direction (ie,the axial line direction D11), the reduction in the strength of the intermetallic compound 145 can be suppressed and the connection strength can be further increased.

[0052] Furthermore, in the present embodiment, the insertion end 141-1 of the stainless steel tube 141 and the receiving end 142-1 of the aluminum tube 142 each have a substantially cylindrical shape in which the diametrical dimensions in the axial line direction D11 are unchanged. According to this structure, the brazing material portion 143 between the insertion end 141-1 and receiving end 142-1 having a substantially cylindrical shape is formed in a substantially cylindrical shape, so that the stress direction on the intermetallic compound 145 is almost the shear direction (i.e., the axial line direction D11). Since the stress direction is almost the shear direction (i.e., the axial line direction D11), the reduction in the strength of the intermetallic compound 145 can be suppressed, and the bonding strength can be further increased.

[0053] This concludes the description of the first embodiment. Next, a second embodiment will be described. In the second embodiment, the direction of the unevenness of the projecting load-bearing portion 144a, which is a constituent of the load-bearing portion 144, was modified into a recessed shape, which is the reverse of that of the first embodiment. The following description will focus only on the changes.

[0054] Fig. Fig. 4 is a view showing a load receiving portion in the second embodiment at the same enlarged cross-sectional area as in Fig. 3 shows. In Fig. 4 are components that meet the Fig. 3 shown components are the same and are necessary for the description, with the same reference numerals as in Fig. 3, whereby a duplicate description of these identical components is omitted below.

[0055] A load-bearing portion 244 in the second embodiment is formed by a depressed load-bearing portion 244a, which is depressed in the diameter direction D12 of the stainless steel pipe 141 from the stainless steel side joint surface 141a. The depressed load-bearing portion 244a of the present embodiment has a curved depressed shape in which the inner surface is depressed to form a part of a spherical surface. The brazing material portion 143 is provided penetrating into this depressed load-bearing portion 244a. The depressed load-bearing portion 244a is formed by protruding the stainless steel pipe 141 from the outside to the inside. A protrusion 241c is formed at a position on the inner surface 141b of the stainless steel pipe 141 corresponding to the depressed load-bearing portion 244a.The four depressed load-bearing portions 244a are arranged at a distance of 90° in the circumferential direction D13 around the tube axis X2. The load-bearing portion 244 comprising these four depressed load-bearing portions 244a then absorbs the loading load F11 in the axial line direction D11 by the brazing material portion 143 formed between the depressed load-bearing portion 244a and the aluminum tube 142 penetrating into the respective depressed load-bearing portions 244a. Also in . Fig. 4(B) is as in Fig. 3(B) the recessed load-bearing section 244a is shown with greater emphasis.

[0056] Of course, the second embodiment described above can also increase the joining strength with respect to the soldering point of the stainless steel pipe 141 and the aluminum pipe 142, as can the first embodiment described above.

[0057] Furthermore, in the present embodiment, the load-bearing portion 244 is formed by the depressed load-bearing portion 244a, which is depressed in the diametrical direction D12 from the stainless steel side joint surface 141a, and the brazing material portion 143 is provided penetrating into the depressed load-bearing portion 244a. According to this configuration, a simple structure such as the penetration of the brazing material 143a into the depressed load-bearing portion 244a through which the load-bearing portion 244 is formed can efficiently absorb the stress load F11 in the axial line direction D11, so that peeling of the intermetallic compound 145 can be further suppressed.

[0058] This concludes the description of the second embodiment. Next, a third embodiment will be described. The third embodiment is a modification of the above-described second embodiment, in which the shape of the component of the load-bearing portion 244 has been changed. The following description will be given with attention only to this change.

[0059] Fig. Fig. 5 is a view showing a load receiving portion in the third embodiment at the same enlarged cross-sectional area as in Fig. 3(A) and Fig. 4(A) shows. In Fig. 5 are components that meet the Fig. 4 shown components are the same and are necessary for the description, with the same reference numerals as in Fig. 4, whereby a duplicate description of these identical components is omitted below.

[0060] A load-bearing portion 344 in the third embodiment, like the second embodiment described above, is formed in a depressed shape that is depressed in the diametrical direction D12 of the stainless steel pipe 141 from the stainless steel side joint surface 141a. The load-bearing portion 344 of the present embodiment is composed of load-bearing grooves 344a that are continuously depressed in the circumferential direction D13 all around. The load-bearing groove 344a has a rectangular groove shape in which the cross-sectional area is rectangularly depressed. Further, the load-bearing groove 344a is formed by shaving the stainless steel side joint surface 141a, and no corresponding protrusion, etc., is formed at a position of the inner surface 141b of the stainless steel pipe 141 corresponding to the load-bearing groove 344a.By penetrating the load-receiving groove 344a, the brazing material portion 143 formed between the load-receiving groove 344a and the aluminum tube 142 absorbs the loading load F11 in the axial line direction D11.

[0061] Of course, the third embodiment described above can also increase the joining strength with respect to the soldering point of the stainless steel pipe 141 and the aluminum pipe 142, as can the first embodiment described above.

[0062] Furthermore, even in the present embodiment, by a simple structure such as the penetration of the brazing material 143a into the load receiving groove 344a, the stress load F11 in the axial line direction D11 can be efficiently absorbed, so that peeling of the intermetallic compound 145 can be further suppressed.

[0063] This concludes the description of the third embodiment. Next, a fourth embodiment will be described. The fourth embodiment is a modification of the above-described third embodiment, in which the shape of the shaved load-receiving groove 344a, which is a constituent part of the load-receiving portion 344, has been changed. The following description will be given with attention only to this change.

[0064] Fig. Fig. 6 is a view showing a load receiving portion in the fourth embodiment at the same enlarged cross-sectional area as in Fig. 5 shows. In Fig. 6 are components that meet the requirements Fig. 5 shown components are the same and are necessary for the description, with the same reference numerals as in Fig. 5, whereby a duplicate description of these identical components is omitted below.

[0065] Also, a load-bearing portion 444 in the fourth embodiment, like the third embodiment described above, is recessed in the diametrical direction D12 of the stainless steel pipe 141 from the stainless steel side joint surface 141a and is composed of load-bearing grooves 444a continuously extending in the circumferential direction D13. The load-bearing groove 444a of the present embodiment has a triangular groove shape in which the cross-sectional area is triangular, and also forms the load-bearing portion 444 with a serrated cross-sectional area by being provided in a plurality of adjacent portions in the axial line direction D11. As another example of the load-bearing groove forming the load-bearing portion with a serrated cross-sectional area, the load-bearing grooves may be provided in a spiral order.

[0066] The respective load-bearing grooves 444a arranged adjacent to one another in the axial direction D11 further include a load-bearing inclined surface 444a-1 inclined toward the stainless steel side connection surface 141a and supporting the load F11. That is, the load-bearing portion 444 should include a plurality of load-bearing inclined surfaces 444a-1 arranged adjacent to one another in the axial direction D11. The brazing material 143a of the brazing material portion 143 is then provided penetrating into the plurality of load-bearing grooves 444a, each of which includes the load-bearing inclined surface 444a-1.

[0067] Of course, the fourth embodiment described above can also increase the joining strength with respect to the soldering point of the stainless steel pipe 141 and the aluminum pipe 142, as can the first embodiment described above.

[0068] Furthermore, in the present embodiment, as in the second embodiment described above, by a simple structure such as the penetration of the brazing material 143a into the load receiving groove 444a, the stress load F11 in the axial line direction D11 can be efficiently absorbed, so that peeling of the intermetallic compound 145 can be further suppressed.

[0069] Furthermore, in the present embodiment, the load-bearing groove 444a is provided in a plurality of adjacent slots in the axial direction D11. According to this structure, by penetrating the brazing material 143a into the plurality of load-bearing grooves 444a arranged adjacently on the stainless steel side joining surface 141a, the loading load F11 in the axial direction D11 can be more effectively absorbed, so that peeling of the intermetallic compound 145 can be further suppressed.

[0070] Furthermore, in the present embodiment, the load-bearing portion 444 has the load-bearing inclined surface 444a-1 inclined toward the stainless steel side joining surface 141a. According to this structure, the load-bearing inclined surface 444a-1 can widely absorb the stress load F11 in the axial line direction D11 and largely suppress peeling of the intermetallic compound 145, so that the joining strength with respect to the solder joint can be further increased.

[0071] The first to fourth embodiments described above are merely representative forms of the present invention, and are not intended to be limiting. That is, various modifications are possible within a range not deviating from the gist of the present invention. As long as these modifications also encompass the structure of the connecting pipe, the device, and the refrigeration cycle system of the present invention, they are naturally included within the scope of the present invention.

[0072] For example, in the first to fourth embodiments described above, as an example of a connecting pipe and a device, the electrically operated valve 10 used as the expansion valve 100 in the refrigeration cycle system 1 and the connecting pipe 14 as a constituent thereof are exemplified. However, the device is not limited to an electrically operated valve as an expansion valve, but may also be various types of valve devices other than an electrically operated valve, such as a solenoid valve, a manual valve, etc., or various types of valve devices other than an expansion valve, such as a flow path switching valve, a check valve, a shut-off valve, etc.Furthermore, the device is not limited to a valve device, but can be various types of devices such as an accumulator, an oil separator, a compressor, various types of heat exchange devices, a hair dryer, a switch, a sensor, etc., as long as a connecting pipe is included. Furthermore, the connecting pipe is not limited to application to a valve device, and the connecting pipe can also be applied to the various types of devices described above.

[0073] Furthermore, in the first to fourth embodiments described above, as an example of a connecting pipe and a device, the electrically operated valve 10 comprising two connecting pipes 14, that is, the first connecting pipe 12 and the second connecting pipe 13, and the connecting pipe 14 as a constituent thereof are exemplified. Then, as examples of a load receiving portion provided to a connecting pipe, the load receiving portions 144, ..., 444 provided to all the connecting pipes 14 are exemplified. However, the connecting pipe, the device, and the load receiving portion provided to the connecting pipe are not limited to these. The number of the connecting pipes can be set to any number, and further, the load receiving portion may be formed only in some of a plurality of connecting pipes required according to the environment in which they are used.

[0074] Furthermore, in the first to fourth embodiments described above, as an example of a connecting pipe, the connecting pipe 14 in which the stainless steel pipe 141 is inserted into the aluminum pipe 142 is exemplified. However, the connecting pipe is not limited thereto, and unlike the above-described embodiments, the inner diameter of the stainless steel pipe in the connecting portion may be larger than the outer diameter of the aluminum pipe, and the aluminum pipe may be inserted into the stainless steel pipe.

[0075] Furthermore, in the first to fourth embodiments described above, the following various load-bearing portions are exemplified as examples of a load-bearing portion. That is, the load-bearing portions 144, 244, which consist of the four projecting load-bearing portions 144a and the recessed load-bearing portions 244a arranged adjacent to each other at a pitch of 90° in the circumferential direction D13, are exemplified. Furthermore, the load-bearing portion 344, which consists of the load-bearing grooves 344a arranged continuously all around in the circumferential direction D13, and the load-bearing portion 444, which is formed by arranging such load-bearing grooves 444a adjacent to each other a plurality of times in the axial line direction D11, are exemplified. However, the load-bearing portion is not limited to these, and its specific shape, etc., can be any as long as it can receive a load in the axial line direction.However, as described above, in a load-bearing portion consisting of projections, recesses, or a single groove or a plurality of grooves, the loading load can be efficiently absorbed by a simple structure.

[0076] Furthermore, in the first to fourth embodiments described above, as examples of a load-bearing portion, the load-bearing portions 144, ..., 444 in which the dimension in the axial line direction D11 is greater than the layer thickness t11 of the intermetallic compound 145 are exemplified. Furthermore, in these load-bearing portions 144, ..., 444, the dimension in the crossing direction, namely, in the diameter direction D12, is also greater than the layer thickness t11 of the intermetallic compound 145. However, the load-bearing portion is not limited to this, and the dimension in the axial line direction and the crossing direction may also be equal to or smaller than the layer thickness of the intermetallic compound.However, as described above, the stress load F11 can be effectively suppressed from directly acting on the intermetallic compound 145 by making the dimension in the axial line direction and crossing direction larger than the layer thickness t11 of the intermetallic compound 145.

[0077] Furthermore, in the first to fourth embodiments described above, as an example of a brazing material portion formed between a stainless steel pipe and an aluminum pipe, the brazing material portion 143 formed in a substantially cylindrical shape corresponding to the shape of each pipe is exemplified. However, the brazing material portion is not limited to this, and a stainless steel pipe and an aluminum pipe having a shape other than a pipe can be used, and thereby a brazing material portion in a shape other than a pipe can be formed. However, as described above, by forming the brazing material portion 143 in a substantially cylindrical shape and thereby making the stress direction on the intermetallic compound 145 almost the shear direction (ie,the axial line direction D11). [List of reference symbols] 1 refrigeration cycle system 10 electrically operated valve 11 Device main body 11a Valve chamber 11b Valve body 11c Valve seat component 12 first connecting pipe 13 second connecting pipe 14 Connecting pipe 100 expansion valve 101 first pipe 102 second pipe 200 heat exchanger outdoor unit 300 heat exchanger indoor unit 400 Flow path switching valve 500 compressor 111 housings 111-1 Valve main body 111-2 Housing 111a Floor wall section 111b Surrounding wall section 141 stainless steel pipe 141-1 Introductory 141a Stainless steel side connection surface 141b, 142a inner surface 141c Deepening 142 aluminum tube 142-1 End of recording 142a-1 step section 143 Soldering material section 143a Soldering material 144, 244, 344, 444 load carrying section 144a projecting load-bearing section 145 intermetallic compound 241c lead 244a recessed load-bearing section 344a, 444a load-bearing groove 444a-1 Load-bearing slope surface D11 Axial line direction D12 diameter direction D13 circumferential direction F11 Load L11 insertion length t11 layer thickness t12 margin W11 projection width dimension W12 projection height dimension X1 valve axis X2 tube axis φA outer diameter φB inner diameter

Claims

[1] Valve device comprising a device main body (11) and a connecting pipe (14), characterized by , that in the connecting pipe (14), a stainless steel pipe (141) and an aluminum pipe (142) are connected in such a way that their axial line directions (D11) coincide with each other, that one end of the stainless steel tube (141) is connected to a stainless steel valve main body (111-1) of the device main body (11) and the other end of the stainless steel tube (141) is connected to the aluminum tube (142), that the stainless steel tube (141) and the aluminum tube (142) are connected by soldering by means of a soldering material (143a) and a soldering material section (143) is formed between the stainless steel tube (141) and the aluminum tube (142), that a load-bearing portion (144, 244, 344, 444) for receiving a load in the axial line direction (D11) is provided on a connecting surface of the stainless steel tube (141) and the brazing material portion (143), and that the load-bearing portion (144, 244, 344, 444) is formed by a load-bearing groove (344a, 444a) recessed in a diameter direction (D12) starting from a stainless steel side connecting surface (141a) of the connecting surface, wherein the stainless steel side connecting surface (141a) is a surface on the side of the stainless steel pipe (141), and the brazing material portion (143) is provided penetrating into the load-bearing groove (344a, 444a). [2] Valve device according to claim 1, characterized by that the load-bearing groove (344a, 444a) is provided several times next to each other in the axial line direction (D11) or is provided in a spiral sequence. [3] Valve device comprising a device main body (11) and a connecting pipe (14), characterized by , that in the connecting pipe (14), a stainless steel pipe (141) and an aluminum pipe (142) are connected in such a way that their axial line directions (D11) coincide with each other, that one end of the stainless steel tube (141) is connected to a stainless steel valve main body (111-1) of the device main body (11) and the other end of the stainless steel tube (141) is connected to the aluminum tube (142), that the stainless steel tube (141) and the aluminum tube (142) are connected by soldering by means of a soldering material (143a) and a soldering material section (143) is formed between the stainless steel tube (141) and the aluminum tube (142), that a load-bearing portion (144, 244, 344, 444) for receiving a load in the axial line direction (D11) is provided on a connecting surface of the stainless steel tube (141) and the brazing material portion (143), and that the load-bearing portion (144, 244, 344, 444) is formed by a projecting load-bearing portion (144a) which projects from a stainless steel side connecting surface (141a) of the connecting surface, wherein the stainless steel side connecting surface (141a) is a surface on the side of the stainless steel pipe (141), in a diameter direction (D12) of the stainless steel pipe (141), and the projecting load-bearing portion (144a) is provided penetrating into the brazing material portion (143). [4] Valve device according to one of the preceding claims, characterized bythat the load-bearing portion (144, 244, 344, 444) has a load-bearing inclination surface (444a-1) which is inclined to the stainless steel side connection surface (141a) of the connection surface. [5] Valve device according to one of the preceding claims, characterized by that a dimension of the load-bearing portion (144, 244, 344, 444) in the axial line direction (D11) is greater than a layer thickness (t11) of an intermetallic compound formed between the stainless steel side joining surface (141a) of the joining surface and the brazing material (143a). [6] Valve device according to one of the preceding claims, characterized by that a dimension of the load-bearing portion (144, 244, 344, 444) in a crossing direction crossing the axial line direction (D11) is greater than a layer thickness (t11) of an intermetallic compound formed between the stainless steel side connecting surface (141a) of the connecting surface and the brazing material (143a). [7] Valve device according to one of the preceding claims, characterized by in that in the stainless steel tube (141) and the aluminum tube (142), the inner diameter of one tube is larger than the outer diameter of the other tube, the other tube is inserted into one tube by a certain length, and the brazing material section (143) is formed in a substantially cylindrical shape between the outer peripheral surface of the other tube and the inner peripheral surface of the one tube. [8] Refrigeration cycle system, characterized by that it comprises the valve device according to one of the preceding claims.

Images