Copper pipe expansion joints, heat transfer circuit components and heat transfer circuit devices using the same, and copper pipe expansion tools

Abstract

To provide a copper pipe expansion joint which can be easily and reliably brazed even by an unskilled worker, and a heat medium circuit component and a heat medium circuit device using the same. [Solution] A copper expansion joint is formed by inserting and fitting the end of a first copper tube 1 into the expanded portion 3 of a second copper tube 2 and brazing the outer periphery of the first copper tube to the expanded portion 3 of the second copper tube.By forming a large diameter expanded portion 4 at the end of the expanded portion 3 of the second copper tube and providing a brazing material reservoir portion 5 to create a copper expansion joint, it is possible to improve work efficiency, productivity, and quality.

Description

[Technical field]

[0001] This invention relates to a copper pipe expansion joint that ensures airtight connection of a heat transfer medium circuit, a heat transfer medium circuit component and a heat transfer medium circuit device that use the same, and a copper pipe expansion jig for manufacturing the copper pipe expansion joint. [Background technology]

[0002] When connecting copper tubes in a heat transfer circuit, a first copper tube is inserted into a second copper tube with an expanded inner diameter to make the inner diameters the same, and brazing material is poured into the gap at the connection to ensure airtightness. Hereinafter, expanding the inner diameter of a copper tube is referred to as "expanding," and the end of the copper tube formed by "expanding" is referred to as the "expanded section."

[0003] The alloy components and proportions of solder used for brazing often vary depending on the manufacturer, but phosphorus copper solder is the most commonly used.

[0004] The current soldering process involves heating with a torch using acetylene gas. The copper tube is heated with a solder rod, and once the appropriate temperature is reached, the solder rod is inserted into the part to be soldered. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 58-221670 Summary of the Invention [Problem to be solved by the invention]

[0006] The brazing process described above requires experience and depends greatly on the skill level of the worker. Inexperienced workers tend to use a large amount of brazing material, and there are many problems with the amount of brazing material used and the appearance, such as the solder flowing onto the surface of the copper pipe. Because of these problems, brazing work has been considered a 3K job even within companies. Even when assembling heat transfer circuit components and heat transfer circuit devices using conventional copper pipe expansion joints, there were problems such as a large amount of brazing material being used, the skill of the worker being required, and the work time being long.

[0007] The present invention aims to provide a copper expansion pipe joint that is simply and reliably brazed to solve these conventional problems, and from another perspective, to provide a heat transfer medium circuit component and a heat transfer medium circuit device that use such a copper expansion pipe joint. [Means for solving the problem]

[0008] The present invention relates to a copper expansion joint formed by inserting and fitting the end of a first copper tube (1) into the expanded portion (3) of a second copper tube (2) and brazing the outer periphery of the first copper tube to the expanded portion (3) of the second copper tube, characterized in that a large-diameter expanded portion (4) is formed at the end of the expanded portion (3) of the second copper tube to provide a brazing material reservoir portion (5).

[0009] The present invention also relates to a heat transfer circuit part that uses the above-mentioned copper pipe expansion joint.

[0010] The present invention also relates to a heat transfer medium circuit device that uses the above-mentioned copper pipe expansion joint.

[0011] The present invention also relates to a heat transfer medium circuit component, which is an expansion valve, a four-way valve, a solenoid valve, a check valve, a muffler (silencer), a strainer (filter), a dryer, a receiver tank (liquid receiver) or an accumulator (liquid separator).

[0012] The present invention further provides a heat transfer medium circuit device, which comprises a compressor and a heat exchanger.

[0013] Furthermore, the present invention relates to a copper pipe expansion jig which is composed of a conical section, a first cylindrical section, a truncated cone section, and a second cylindrical section in that order from the tip, wherein the taper angle of the conical section is 32 to 37 degrees, the taper angle of the truncated cone is 45 degrees, and wherein (a) in the case of a 3 / 8 inch pipe, the diameter of the first cylindrical section is 10.02 to 10.32 mm and the diameter of the second cylindrical section is 16.00 mm or more, or (b) in the case of a 1 / 2 inch pipe, the diameter of the first cylindrical section is 12.90 to 13.50 mm and the diameter of the second cylindrical section is 19.00 mm or more, and the ratio of the diameter of the second cylindrical section to the diameter of the first cylindrical section is at least 1.45. Effect of the Invention

[0014] According to the copper expansion joint of the present invention, even an unskilled worker can easily and reliably perform brazing work, and problems such as an unnecessary increase in the amount of brazing material used and the flow of the brazing material onto the copper pipe surface, resulting in poor appearance, can be reduced, and work efficiency, productivity, and quality can be improved. As a result, even when assembling heat transfer medium circuit components and heat transfer medium circuit devices using the copper expansion joint of the present invention, the worker does not need to be skilled, and problems such as a large amount of brazing material used and long work time can be avoided. [Brief description of the drawings]

[0015] [Figure 1] 1 is a cross-sectional view of a copper pipe expansion joint of the present invention. [Diagram 2] 2 is a cross-sectional view showing a second copper tube of the copper expansion joint of the present invention and a state in which the first copper tube and the second copper tube are joined together. FIG. [Diagram 3] FIG. 2 is a diagram showing the position of the insert solder in a copper pipe expansion joint according to the present invention and a conventional copper pipe expansion joint. [Figure 4] FIG. 13 is a diagram showing the ring rolling material and the ring rolling material installed in the large diameter expansion section. [Diagram 5] When using ring roll material, this is one of the automation ideas that involves heating the torch nozzle from two points. [Figure 6] 1 is a diagram showing a copper pipe expansion jig for processing a large diameter expanded portion according to the present invention and the expanded state of the pipe. [Figure 7] This shows a check valve for heat transfer circuit components with a large diameter enlarged section. [Figure 8] FIG. 2 is a cross-sectional view of a 3 / 8 inch pipe (3-part pipe) and a 1 / 2 inch pipe (4-part pipe) using the copper expansion joint of the present invention, showing the dimensions of each part. [Figure 9] FIG. 1 is a cross-sectional view showing a second copper tube of a conventional copper expansion joint and a state in which the first copper tube and the second copper tube are joined together. [Figure 10] 1A and 1B are diagrams showing a brazing filler metal reservoir and a brazing filler metal leakage during brazing work using a soldering filler metal in a copper expansion joint according to the present invention and a conventional embodiment. [Figure 11] FIG. 2 is a diagram showing the dimensions of each part of the copper pipe expansion jig of the present invention for 3 / 8 inch pipes (3-part pipe) and 1 / 2 inch pipes (4-part pipe). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the following description, the large diameter expanded portion may be referred to as a "tulip processed portion."

[0017] The copper expansion joint of the present invention is characterized in that the end of the expanded portion (3) of the second copper pipe (2) into which the first copper pipe (1) is inserted and joined is expanded to form a large-diameter expanded portion (4) (tulip processed portion) by the diameter expansion operation, thereby providing a brazing material reservoir portion (5). In other words, by forming the large-diameter expanded portion (4) (tulip processed portion) by the diameter expansion operation on the end of the expanded portion (3) of the second copper pipe (2) and then inserting and joining the first copper pipe (1), a flange with a larger diameter can be provided on the outer periphery of the end of the second copper pipe compared to the expanded portion of a conventional copper expansion joint.

[0018] When the brazing worker inserts the solder into the tulip processing part, he or she simply inserts the solder into the flange of the tulip processing part that expands further from the end of the expanded tube, making positioning easier and improving work efficiency by forming a solder pool that prevents the solder from flowing out of the tulip part. It has also been confirmed that the appropriate amount of solder is filled into the entire expanded tube part (3) when the solder reaches the other side of the insert solder.

[0019] The copper pipe expansion joint referred to in this invention is a joint for connecting copper pipes to form a sealed heat transfer medium circuit device such as an air conditioner compressor and heat exchanger, in which the end of the copper pipe that will be the connection part of the second copper pipe (hereinafter referred to as the "female pipe") is expanded, a first copper pipe (hereinafter referred to as the "male pipe") is inserted into it, and the end of the overlapping joint is brazed to connect them. In other words, it is used for connections when forming a heat transfer medium circuit.

[0020] In order to avoid changing the inside diameter of the pipe in a copper pipe expansion joint, it is necessary to expand the inside diameter of the female pipe to a size that allows the male pipe to be inserted smoothly.

[0021] In copper pipe expansion joints, the gap between the inside diameter of the expanded part of the female pipe and the outside diameter of the male pipe is filled with solder, an alloy with a melting point much lower than that of the copper pipe, by heating and melting it with a torch to ensure a tight seal. Such solder comes in rod-shaped solder and ring-shaped solder.

[0022] In this invention, by providing a flange part with a larger diameter on the outer periphery of the tip of the expanded pipe part that becomes the female pipe in the copper expansion joint, i.e., a large diameter expanded pipe part (tulip processed part), the brazing work can be simplified, which helps to improve work efficiency and avoids the waste of brazing material. In addition, by using a ring braze for the large diameter expanded pipe part (tulip processed part), the brazing work can be automated.

[0023] In the large diameter expansion section (tulip processed section), the molten solder accumulates in that area, forming a solder pool. When using rod-shaped solder, the soldering work can be completed by confirming that the solder has melted and is circulating in the solder pool. In addition, the presence of the large diameter expansion section (tulip processed section) greatly reduces the risk of solder leaking onto the outside of the copper pipe.

[0024] Heat transfer circuit components that use the copper expansion joint of this invention include expansion valves, four-way valves, solenoid valves, check valves, mufflers (silencers), strainers (filters), dryers, receiver tanks (liquid receivers), and accumulators (liquid separators), etc.

[0025] Heat transfer medium circuit devices that use the copper pipe expansion joint of the present invention include compressors and heat exchangers.

[0026] Another aspect of the present invention is to provide a copper pipe expansion tool as a tool for forming the large diameter expanded portion (tulip processed portion). With reference to Fig. 11, the copper pipe expansion tool of the present invention is composed of a conical portion, a first cylindrical portion, a truncated cone portion, and a second cylindrical portion in this order from the tip, the conical portion has a taper angle of 32 to 37 degrees, the truncated cone has a taper angle of 45 degrees, and (a) in the case of a 3 / 8 inch tube, the diameter of the first cylindrical portion is 10.02 to 10.32 mm and the diameter of the second cylindrical portion is 16.00 mm or more, or (b) in the case of a 1 / 2 inch tube, the diameter of the first cylindrical portion is 12.90 to 13.50 mm and the diameter of the second cylindrical portion is 19.00 mm or more, and the ratio of the diameter of the second cylindrical portion to the diameter of the first cylindrical portion is at least 1.45 or more.

[0027] Regarding the specifications of the copper tubes used in the copper expansion joint of this invention, phosphorus deoxidized copper seamless tubes are generally used, and are represented by the JIS number C1220T-0. The outer diameter (φ) sizes of each copper tube are as follows: 2-part tube 1 / 4 inch (6.35 mm) 3 / 8 inch (9.52 mm) Quarter tube 1 / 2 inch (12.7 mm)

[0028] There are no set standards for the expansion dimensions of female pipes, and they are generally determined by the design standards of each company at their discretion. Therefore, in the embodiment of this invention, the expansion dimensions for 3mm and 4mm copper pipes are shown in Figure 8 as an example.

[0029] The solder used in this invention is preferably phosphorus copper solder, and its composition, melting temperature, JIS number, product number, and outer diameter (φ) are as follows. Phosphorus 7%, Copper 93% 735~845℃ JIS-Z3264 BCup-2 2.4φ

[0030] It was found that the brazing time for the copper pipe expansion joint of this invention was about 20% shorter than that of the conventional method. If a ring braze is used, the time can be shortened by about 30%.

[0031] With the copper expansion joint of this invention, the defect rate due to solder leakage can be reduced by about 30% compared to the conventional method.

[0032] The reason for the reduction in work time and defect rate is that the large diameter expansion section (tulip processing section) makes it easy to visually check the flow and accumulation of solder during the soldering work. When soldering, acetylene gas is sprayed into the torch nozzle and ignited with a lighter, and then oxygen is added and the amount of oxygen is adjusted while checking the color of the flame. This work is done with sunglasses, so there was a problem with the past, such as not being able to visually check fine details.

[0033] In addition, by processing the tulip, the area can be used as a place for the ring rope, which eliminates the need for a solder rod, improving efficiency. Furthermore, in the case of ring rope, the amount of solder can be controlled appropriately, which reduces the material cost of the solder.

[0034] Regarding the tube expansion process, by using the tube expansion tool of the present invention described above, the female tube can be efficiently expanded with fewer steps. That is, since the tube expansion tool of the present invention has a conical portion, a first cylindrical portion, a truncated cone portion, and a second cylindrical portion in that order from the tip, by inserting and pushing this into the female tube opening, it is relatively easy to process the large-diameter expanded portion.

[0035] Tulip processing is a process in which the tip of the soldered part of a copper pipe, etc. is slightly widened. This part allows the solder to accumulate, which is effective in maintaining a reliable airtight seal.

[0036] Furthermore, by installing a ring solder on the tulip processed part of the soldering part, it is possible to perform soldering with high precision without using conventional rod solder material and since one hand is free.

[0037] The copper expansion joint of the present invention can be suitably used to connect copper pipes in heat transfer circuit components such as expansion valves, four-way valves, solenoid valves, check valves, mufflers (silencers), strainers (filters), dryers, receiver tanks (liquid receivers) or accumulators (liquid separators) used in air conditioners.

[0038] The copper pipe expansion joint of the present invention is ideal for connecting copper pipes, which requires many pipe connections when designing and installing heat transfer medium piping equipment such as compressors and heat exchangers inside air conditioners. [Explanation of symbols]

[0039] 1. First Copper Tube 2. Second copper tube 3. Expanded section of second copper tube 4. A further large diameter expansion section (tulip processing section) is formed around the expansion section of the second copper tube. 5. Brazing material 6 Row bar 7. Dripping solder from conventional soldering 8 Ring Row 9. Welding torch nozzle 10 Tube expansion tool 11 Tulip processing part of the check valve, which is a heat transfer component

Claims

1. A copper expansion joint formed by inserting and fitting the end of a first copper tube (1) into the expanded portion (3) of a second copper tube (2) and brazing the outer periphery of the first copper tube to the expanded portion (3) of the second copper tube, characterized in that a large diameter expanded portion (4) is formed at the end of the expanded portion (3) of the second copper tube to provide a brazing material reservoir portion (5).

2. A heat transfer circuit part using the copper pipe joint according to claim 1.

3. A heat transfer medium circuit device using the copper pipe joint according to claim 1.

4. 3. The heat transfer medium circuit component according to claim 2, wherein the heat transfer medium circuit component is an expansion valve, a four-way valve, a solenoid valve, a check valve, a muffler (silencer), a strainer (filter), a dryer, a receiver tank (liquid receiver), or an accumulator (liquid separator).

5. A copper pipe expansion jig consisting of a conical section, a first cylindrical section, a truncated cone section, and a second cylindrical section in that order from the tip, wherein the taper angle of the conical section is 32 to 37 degrees, the taper angle of the truncated cone is 45 degrees, and wherein (a) in the case of a 3 / 8 inch pipe, the diameter of the first cylindrical section is 10.02 to 10.32 mm and the diameter of the second cylindrical section is 16.00 mm or more, or (b) in the case of a 1 / 2 inch pipe, the diameter of the first cylindrical section is 12.90 to 13.50 mm and the diameter of the second cylindrical section is 19.00 mm or more, and the ratio of the diameter of the second cylindrical section to the diameter of the first cylindrical section is at least 1.45.

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