JPS6410299B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a U-tube chucking unit for selectively inserting and connecting a predetermined pair of pipe ends of a heat exchanger of an air conditioner, for example.

Generally, as shown in FIG. 1, in a heat exchanger for an air conditioner, a large number of straight pipes 1 made of copper alloy having the same diameter are arranged in a staggered pattern and are supported by penetrating opposing frames 2. A large number of fins 3 made of a good thermal conductor such as aluminum foil are provided between them.
The pipe ends are shifted one by one and connected with a U-shaped pipe 4 so that the refrigerant flows through all the straight pipes.

Furthermore, as shown in FIG. 2, there are several types of U-tube arrangements, designated by symbols a to f, depending on the model.

Conventionally, the process of inserting the U-shaped tube into the pipe end was done manually, which resulted in the U-shaped tube being forcefully inserted into the pipe end at an angle, resulting in inconsistent insertion depth and poor reliability. There was a problem that caused damage.

The present invention solves the above-mentioned problems and allows the ends of pipes arranged like a heat exchanger to be automatically inserted according to a predetermined pattern, thereby making the insertion depth of the U-shaped tube uniform and improving reliability. It is an object of the present invention to provide a U-shaped tube chucking unit that can be improved.

Hereinafter, one embodiment shown in the drawings will be described in detail.

FIG. 3 shows an example of a U-shaped tube used in the tracking unit of the present invention. As an example of specific dimensions, the center distance D is 25 mm, and the center height is 18.5 mm.
mm, the pipe diameter is 9.52mm.

Figures 4a, b and c are partially sectional front views of a U-tube chucking unit (hereinafter referred to as the unit);
FIG. 2 is a plan view and a partially sectional side view. In these figures, 5 is the main body, 6 is the recess, 7 is the knockout, 8 is the push pin, 9 is the bush, 10 is the knockout spring, 11 is the chucking lever, and 11a.
13 is a lever spring, 13 is a lever pin, and 14 is a chuck adjustment pin. More specifically, the main body 5 has a rectangular cross section with chamfered corners, and the lower end forms a recess 6 having an opening on the end face and one side (the left side in FIG. 4c). and recess 6
A knockout 7 is housed in the housing so as to be slidable in the vertical direction, and a hole 12 is formed on both sides of the upper surface of the knockout 7 to loosely fit a push pin 8 inserted therein by press-fitting or screwing. .

A larger hole is coaxially formed on the upper side of the main body of the hole 12, and a bush 9 for guiding the push pin 8 is fitted therein. A push pin 8 on one side is inserted so that the knockout 7 is always brought into contact with the upper part of the recess.
A helical spring 10 serving as a knockout spring is interposed between the head 8a and the upper surface of the bush 9. As is clear from the figure, the lower surface of the knockout 7 is formed with a curved surface portion 7a complementary to the curved surface of the bent portion of the U-shaped tube 4 shown by the chain line. Also, the thickness of the knockout 7 accommodated in the recess 6 is the same as that of the U-shaped tube 4.
When the U-shaped tube is pressed into the recess 6, the U-shaped tube protrudes beyond the knockout 7. A recess 15 is formed in which the other end of a pair of chucking levers 11, which are arranged symmetrically and substantially L-shaped with one end in contact with each side of the U-shaped tube, is buried. A circular hole 16 is further bored in the upper part of the recess 15, and a helical spring 11a serving as a lever spring is housed therein.
Centering around a lever pin 13 inserted from the side of the main body 5 at a substantially central position of the chucking lever 11, the ends of the chucking lever 11 are biased in a direction to press against both ends of the U-shaped tube. are doing. In order to adjust the pressing force on both ends of the U-shaped tube, a small screw 14 serving as a chuck adjustment pin is inserted into a screw hole 5a formed in the main body 5 at a position closer to the U-shaped tube than the position of the lever pin 13. is screwed into.

Reference numeral 17 indicates a part of a chuck setting plate which is a positioning means. Check setting plate 17
As shown in Fig. 2, a group of circular holes 18, 19, . At the same time, one piece is provided at the center position of the circumference. Again in FIG. 4a, the pattern a
-f is selected, the unit is fitted into a pair of predetermined circular holes in the chuck setting plate 17, and the chuck support fitting 25 is inserted into the groove 9a of the bush 9 to prevent it from coming off.

The operation of the unit configured as above will be explained. In FIG. 5, when the U-shaped tube 4 is inserted into the lower end of the unit main body 5, the U-shaped tube 4 is held by the main body 5 by the chucking lever 11 and does not fall off.
Therefore, the unit is moved to a position corresponding to a predetermined pair of pipes 1 by a moving means (not shown), and the fact that it is located at that position is detected by, for example, a micro switch, and the knockout plate 26 is moved from above the unit. is lowered in the direction of arrow A by reciprocating means (not shown), and the pair of push pins 8 are pushed down through the plate 26 against the action of the knockout spring 10. When the push pin 8 is pressed down, the knockout 7 is lowered (see FIG. 4a), and the U-shaped tube 4 is inserted into the desired pipe 1. Since the U-shaped tube is pushed down from above with a uniform force, it is not forced into the U-shaped tube while being tilted, and can be inserted into the pair of pipes at the same depth.

As explained above, the U-shaped tube chucking unit of the present invention has the following effects.

Since the U-shaped tube can be inserted into a pair of pipes immediately and with uniform force without tilting, and the insertion depth can be made uniform, reliability can be improved.

[Brief explanation of the drawing]

1a and 1b are a plan view and a front view showing a heat exchanger of an air conditioner to which the U-shaped tube switching unit of the present invention is applied; FIG. 2 is a plan view showing an arrangement pattern of U-shaped tubes; Figure 3 is a front view showing an example of a U-shaped tube;
4a, b and c are a partially sectional front view, a plan view and a partially sectional side view showing an embodiment of the present invention, respectively, and FIGS. 5 and 6 are for explaining the operation of the embodiment. FIG. In the figure, 4 is a U-shaped tube, 5 is a main body, 6 is a recess, 7 is a knockout, 8 is a push pin, 9 is a bush, 1
1 is the chucking lever, 17 is the chuck setting plate.

Claims (1)

[Claims] 1 A switching unit for fitting and connecting a U-shaped pipe to a pair of pipe ends, which has a recess 6 having an opening on a lower end face and one side, and the recess 6 The U-shaped tube is housed in the upper part of the recessed part 6 so as to be movable up and down, and is always biased in the direction of colliding with the upper part of the recessed part. A knockout 7 having a curved surface portion that comes into contact with the knockout 7, a push pin 8 that is formed substantially integrally with the knockout 7 and lowers the knockout 7 by being pushed, and a push pin 8 that is bored in the upper part of the main body 5. A bush 9 is inserted into the hole with its upper part protruding from the upper end surface of the main body 5 and guides the push pin 8, and the tip thereof is exposed to the space of the recess 6 after accommodating the knockout 7, so that the bush 9 is always in contact with the push pin 8. a chucking lever 1 that is biased in a direction in which its tip end enters the space of the recess 6 and presses both ends of the U-shaped tube;
1. A U-shaped tube connecting unit characterized by comprising: 1.