JP2002316227A - Flare expanding device of heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flare expanding device of a heat exchanger capable of preventing any bucking during the flare expansion, improving the quality, and omitting any punch exchanging work during the model change. SOLUTION: In the flare expanding device in which a heat transfer pipe 3 of the heat exchanger 1 is positioned with respect to a punch 10, and the flare expansion of the heat transfer pipe 3 is performed by this punch 10, the flare expansion is performed by an air-drive unit provided independently for each punch 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flare expansion device for a heat exchanger used in an air conditioner or the like, and more particularly, to a flare expansion process for a heat exchanger, which does not cause a decrease in work quality due to a processing load. The present invention relates to a flare expansion device that does not require component replacement work when changing models.

[0002]

2. Description of the Related Art FIG.
And FIG. 6 is a perspective view of a main part of FIG. 5, and FIG. 7 is a primary expansion pipe and a secondary expansion pipe of a heat transfer tube of a heat exchanger. FIG. 8 is an explanatory view showing flare expansion, and FIG. 8 is an operation explanatory view of the part A in FIG. 1
Is a heat exchanger as a work, and in FIG.
As shown in (a), a primary expanded heat exchanger for uniformly expanding the heat transfer tube 3 over its entire length and bringing it into close contact with the fins is shown. 2 is a fin of the heat exchanger 1, 3 is a heat transfer tube of the heat exchanger 1, and 4 is a work guide. 20 is a flare expansion device, 21 is a punch, 22 is a punch mounting plate on which a plurality of punches 21 are mounted, and 23 is a hydraulic cylinder for vertically moving the punch mounting plate 22.

The operation of the flare expansion device 20 of the heat exchanger 1 configured as described above will be described. The heat exchanger 1 is set in the flare expansion device 20, and the work guide 4 is pressed against the fin 2 from four directions of the heat exchanger 1, and the heat transfer tube 3 of the heat exchanger 1 is moved to the punch 21 of the flare expansion device 20. Position. Next, the hydraulic cylinder 23 is driven, and the punch mounting plate 22 on which the punch 21 is mounted is slowly lowered with a large load by hydraulic driving (about 20 mm / sec), and the punches 21 are simultaneously inserted into all the heat transfer tubes 3. Then, a secondary expansion pipe (FIG. 7 (b)) for inserting a vent pipe connecting the heat transfer pipes 3 and a flare expansion pipe (FIG. 7 (c)) for accumulating wax when brazing the vent pipe. At the same time. At this time, a processing load of about 100 kgf is applied per one pipe.

[0004] Of the secondary expansion and the flare expansion, the secondary expansion is performed for all the heat transfer tubes 3, but for the flare expansion, a leak test in a later process seals the connection between the heat transfer tube 3 and the pipe with the pipe outer diameter. In the case of the method, the heat transfer tube 3 connected to the pipe cannot be flared (performed after a leak test). Therefore, a special punch that performs only the secondary expansion is separately produced and used.

[0005]

As shown in FIG. 6, when the heat exchangers 1, which are a plurality of workpieces, are handled in a stacked state, the fins 2 are provided between the heat exchangers 1 for reasons of the construction of the production line.
Will be held together, as shown in FIG.
The ends of the fins 2 may overlap and a biting state may occur. In this case, the heat transfer tube 3 cannot support the force in the bending direction due to the processing load during flare expansion, and FIG.
As shown in (b), buckling of the heat transfer tube 3 may occur, and the heat transfer tube 3 may bend. In addition, in the design of the refrigerant circuit, the layout of the connection of the heat transfer tubes 3 differs depending on the model, and the position of the heat transfer tubes 3 connected during the leak test is not constant.
It was necessary to exchange the mounting position of the exclusive punch 21 when changing the model.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and aims to improve the quality by eliminating the buckling of the heat transfer tube at the time of flare expansion, and to eliminate the punch replacement work when changing the model. It is an object of the present invention to provide a flare expansion device for a heat exchanger.

[0007]

SUMMARY OF THE INVENTION The present invention relates to a flare expansion apparatus for positioning a heat transfer tube of a heat exchanger with respect to a punch, and performing flare expansion of the heat transfer tube with the punch.
Flare expansion processing was performed by an air drive unit provided independently for each punch. Further, the air drive unit or the punch and the air drive unit are slid in the lateral direction to perform the flare expansion of the heat transfer tube.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS [Embodiment 1] FIG. 1 is an explanatory view of a flare expansion apparatus according to Embodiment 1 of the present invention, and FIGS. 2 and 3 are operation explanatory views of main parts of FIG. In the present embodiment, only the flare expansion process is performed with a light load by air drive in the flare expansion process. More specifically, the flare expansion of the heat transfer tube by the punch of the flare expansion device is performed by the load of the air-driven hammer air cylinder and the impact force of the weight of the hammer.

Reference numeral 1 denotes a heat exchanger serving as a work, which is a heat exchanger after secondary expansion. 2 is the fin of the heat exchanger 1, 3
Denotes a plurality of heat transfer tubes provided in the heat exchanger 1, and 4 denotes a work guide. Reference numeral 5 denotes a flare expansion device, which includes a punch plate 7 and a cylinder frame 8 attached to a movable member 6, and an actuator of a unit air cylinder 9 for driving the movable member 6 in a vertical direction is provided above the movable member 6. Are linked. A punch 10 urged downward by a spring 11 and moving up and down on the punch plate 7 is attached to the punch plate 7.

The upper plate 13a of the cylinder frame 8
The hammer 12 is disposed between the lower plate 13b and the punch 10 so as to be vertically movable in opposition to the punches 10. 14
Is provided to face each hammer 12, and each hammer 12
This is a hammer air cylinder for independently moving up and down, and has a pneumatic circuit that can be individually operated by driving a solenoid valve. The operation order of the hammer 12 can be freely set by sequence control. Thus, the punches 10, the hammers 12, the hammer air cylinders 14 and the like are provided in a number corresponding to the heat transfer tubes 3, and the operation of each punch 10 is individually controlled.

The operation of the first embodiment configured as described above will be described. First, as shown in FIG. 1, the heat exchanger 1 as a work is set, and the work guide 4 is pressed against the heat exchanger 1 to position the heat transfer tube 3 with respect to the punch 10. Next, when the unit air cylinder 9 is operated,
The movable member 6 to which the punch plate 7 and the cylinder frame 8 are attached descends, and as shown in FIG. 2, the punch 10 comes into contact with the heat transfer tube 3 at the tapered start portion. At this time, punch 10
Is lifted because it is free upward, but the heat transfer tube 3 is not machined and the spring 1
The state in which the punch 10 is in close contact with the heat transfer tube 3 is maintained by the urging force of 1.

Next, as shown in FIG. 3, the air cylinder 14 for hammer is operated to lower the hammer 12 with respect to the heat transfer tube 3 for performing flare expansion (the descent speed is about 200 mm / h).
sec), and collide with the upper end of the punch 10. The taper surface of the punch 10 is inserted into the heat transfer tube 3 by this impact force, and as a result, a flare shape is formed. At this time, the load of the hammer air cylinder 14 is about 8 kgf, the own weight of the hammer 12 is about 2 kgf, and the processing load per heat transfer tube 3 is about 10 kgf. Thus, the heat transfer tube 3
The load applied to the heat exchanger 1 as a work is reduced by reducing the processing load per piece, and the heat transfer tube 3 due to buckling is reduced.
Can be prevented from occurring and quality deterioration.

[Second Embodiment] FIG. 4 is an explanatory view showing a flare expanding apparatus according to a second embodiment of the present invention. In addition,
The same parts as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted. In the present embodiment, the flare expanding portion can be freely selected by sliding the movable member 6 in the horizontal direction. That is, as shown in the figure, a slide mechanism (not shown) that can slide in the lateral direction (left and right direction) is provided on the movable member 6, and the actuator of the sliding air cylinder 15 is connected to the movable member 6, and the punch 10, The hammer 12 and the hammer air cylinder 14 are disposed so as to correspond to every other heat transfer tube 3 (3a to 3h). Then, the movable member 6 can be moved in the left-right direction by the sliding cylinder 15 at the same pitch l as the heat transfer pipe pitch l.
The heat transfer tubes 3 for performing flare expansion by individually controlling the heat transfer tubes 4 can be selected. That is, the operation of each punch 10 is performed individually, and at this time, the operation location can be freely selected.

According to the second embodiment configured as described above, for example, as shown in FIG. 4, the punch 10 is positioned on the first heat transfer tube group 3a, 3c, 3e, 3g, and the unit air The cylinder 9 is operated to lower the movable member 6, and then the air cylinder 14 for the hammer is operated to lower the hammer 12, and the impact force of the punch 10
Is inserted into the heat transfer tube 3 to form a flare shape. Next, the movable member 6 is raised and moved to the left in the figure by the sliding cylinder 15 by the same pitch 1 as the pitch 1 of the heat transfer tubes 3, and the second heat transfer tube groups 3 b, 3 d,
The punch 10 is moved onto 3f and 3h, and in this state, a flare shape is formed on the heat transfer tube 3 in the same manner as above.

As described above, in the present embodiment, the punch 1
0, a hammer 12, and a hammer air cylinder 14 are provided at a pitch of 2 l corresponding to the heat transfer tubes 3, and the punches 10 are individually driven in this state. The punch 1 is provided by providing the slide cylinder 15.
0, the number of hammers 12, and the number of hammer air cylinders 14 can be halved.

If the movable member 6 is not only slid once but also a plurality of times in the lateral direction as described above, the number of punches 10, hammers 12, and hammer air cylinders 14 can be reduced to 1/3. It can be reduced to 1/4. Also, if the cycle time is limited,
The number of the punches 10 may be the same as that of the heat transfer tubes 3, and the number of the hammers 12 and the air cylinders 14 for the hammer may be reduced by sliding.

Thus, by reducing the number of heat transfer tubes 3 processed per operation, the load applied to the heat exchanger 1 as a work can be reduced, and the occurrence of defects due to buckling and the deterioration of quality can be prevented. Further, since the conventional pipe expansion process is dedicated to the secondary pipe expansion, the punch replacement work at the time of model change can be eliminated.

[0018]

As is apparent from the above invention, the present invention relates to a flare expansion apparatus for positioning a heat transfer tube of a heat exchanger with respect to a punch and performing flare expansion processing of the heat transfer tube with the punch. Since the flare expansion process is performed by an air drive unit provided independently for each punch, the processing load per heat transfer tube is reduced, and the load applied to the heat exchanger as a work is reduced. It is possible to prevent bending of the heat transfer tube due to buckling of the heat tube and deterioration of the quality.

In addition, since the air drive section or the punch and the air drive section are slid in the horizontal direction to perform the flare expansion processing of the heat transfer tube, the processing load per heat transfer tube is reduced, and furthermore, the operation load per operation is reduced. By reducing the number of processing, the load on the heat exchanger, which is the work, is reduced,
It is possible to prevent the occurrence of defects due to the buckling of the heat transfer tubes and the deterioration of the quality. In addition, since the conventional pipe expansion process is dedicated to the secondary pipe expansion, the punch replacement work at the time of model change can be eliminated.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of Embodiment 1 of the present invention.

FIG. 2 is an operation explanatory view of a main part of FIG. 1;

FIG. 3 is another operation explanatory view of a main part of FIG. 1;

FIG. 4 is an explanatory diagram of Embodiment 2 of the present invention.

FIG. 5 is an explanatory view showing an example of a conventional flare expansion device.

FIG. 6 is a perspective view of a main part of FIG.

FIG. 7 is an operation explanatory view of a main part of FIG. 5;

FIG. 8 is an operation explanatory view of an a part of FIG. 6;

[Explanation of symbols]

1 heat exchanger, 3 heat transfer tube, 4 work guide, 5 flare expansion device, 6 movable member, 9 unit air cylinder, 10 punch, 12 hammer, 14 hammer air cylinder, 15 slide air cylinder.

Claims (2)

[Claims] 1. A flare expansion device for positioning a heat transfer tube of a heat exchanger with respect to a punch and performing flare expansion of the heat transfer tube with the punch, wherein the flare expansion process is provided independently for each punch. A flare expansion device for a heat exchanger, which is performed by an air drive unit. 2. The flare expansion device for a heat exchanger according to claim 1, wherein the air drive portion or the punch and the air drive portion are slid laterally to perform flare expansion processing of the heat transfer tube.