JPH024730Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention is a differential pressure attachment that is used by appropriately attaching it to the pressure attachment used for pressing the tube expansion mandrel when expanding heat exchanger tubes. Regarding replacement pins.

(Prior Art) Conventionally, the arrangement of tubes to be expanded, that is, the number of vertical and horizontal rows,
When the number of stages is changed, the arrangement of the mandrels for tube expansion must be changed accordingly, and the work of changing the arrangement of the mandrels is extremely complicated and poses a major problem in workability. As a means to solve this problem, the applicant of this invention filed Japanese Patent Application No. 58-46731.
We have developed the means related to this issue first.

In other words, to simplify this conventional method, a plurality of pressing attachments have various pressing surfaces for pressing a mandrel and various through holes for passing the mandrels through, corresponding to various arrangements of pipes to be expanded. This is a means of selecting one pressing attachment corresponding to the arrangement of the pipes to be expanded and pressing only the mandrels necessary for pipe expansion when performing pipe expansion work. There is no need to replace the mandrel at all,
This resulted in a dramatic improvement in workability.

(Problems to be Solved) However, in the above-mentioned conventional method, an extremely large number of pressing attachments having pressing surfaces and mandrel through holes arranged in various arrangements corresponding to various arrangements of pipes to be expanded were manufactured. The problem has arisen that it has to be kept and the cost is very high.

Furthermore, since there are a large number of press attachments, storage space is also a problem, and furthermore, it is easy and quick to choose one press attachment that has an appropriate arrangement of press surfaces for pipe expansion out of a large number of press attachments. It also had the problem of making it difficult to make a selection.

The present invention was devised in view of the above-mentioned problems, and its purpose is to prepare a large number of pressing attachments to have mandrel penetration holes corresponding to various arrangements of pipes to be expanded. The object of the present invention is to minimize the number of press attachments required to be held, thereby reducing the cost, solving the problem of storage space, and solving the difficulty of selecting an attachment.

(Means for solving the problem) The present invention develops a means for freely opening and closing the mandrel penetration hole provided in the press attachment.
This method attempts to solve the above conventional problems by closing the mandrel through holes and arbitrarily changing the formation position and number of the through holes,
The gist of the structure is that a lower stage with a diameter larger than the pin body 1 is formed at one end of the pin body 1 which is formed so as to be fit into the mandrel penetration hole 6 of the pressing attachment 5. A flange-like stepped portion 2 formed to abut with the portion 7 is provided, and a locking mechanism is provided for locking the pin body 1 to the pressing attachment 5 when the pin body 1 is inserted into the through hole 6. A body 3 is separately provided on the pin body 1.

(Function) Therefore, when using the replacement pin configured as described above, the pin body 1 of the pin is inserted into the mandrel penetration hole 6 of the pressing attachment 5, and the locking body 3 is used to hold the pin. By attaching the pin to the press attachment 5 while preventing it from coming off, the mandrel through hole 6 is closed, and the position where the pin is attached can be used as a press surface for pressing the mandrel. Therefore, by attaching and removing a plurality of pins to each mandrel penetration hole 6 of the pressure attachment 5, the arrangement of the pressing surface of the pressure attachment 5 and the mandrel penetration hole 6 corresponds to the arrangement of the tubes to be expanded. It can be changed arbitrarily in various ways. Further, when the pin presses the mandrel, the pin is firmly positioned in the mandrel pressing direction by bringing the stepped portion 2 at one end of the pin body 1 into contact with the lower step 7 of the pressing attachment 5. Therefore, a large pressing force can be applied to the mandrel, and there is no problem in pressing the mandrel.

(Example) Hereinafter, embodiments of the present invention will be described according to an example shown in the drawings.

That is, FIG. 1 shows the replacement pin 17 according to the present invention.
In the figure, 1 indicates a generally cylindrical pin body, and a flange-shaped step 2 having a larger diameter than the pin body 1 is integrally formed at one end of the pin body 1. It becomes. Reference numeral 3 indicates a C-shaped retaining ring, which is a locking body of the present invention, which is attached to a groove 4 carved on the outer periphery of the pin body 1 at a substantially central position.

The present embodiment has the above-mentioned structure. Next, the usage and operation thereof will be explained. First, as shown in FIG.
In the mandrel penetration holes 6 drilled in 3 rows and 10 stages,
In order to match the number of rows and stages of the heat exchanger tubes 16, 16a shown in the lower two-dot chain line in FIG.
is fitted, and the stepped portion 2 is brought into contact with the lower step portion 7 connected to the lower part of the mandrel penetration hole 6, and the C-shaped retaining ring 3 is positioned above the lower member 5b and formed at the lower end of the upper member 5a. It is locked in the groove 8 that has been formed. Therefore, the replacement pin 17 is prevented from accidentally falling off from the pressing attachment 5 by being locked by the C-shaped retaining ring 3. Also,
As shown in FIG. 3, the pressing attachment 5 to which the pin 17 is mounted is attached to a pressing body 10 that is movable up and down by the operation of a cylinder (not shown) separately provided along the guide shaft 9 of the tube expansion device. It is used by sliding it into a space 13 between the lower part and a mounting body 12 formed by locking a number of mandrels 11, 11a, etc. from a space 19 on the side thereof. In the figure, reference numeral 14 indicates an engaging body attached to one side of the pressing attachment 5, and the engaging body 14 is a reciprocating rod having an engaging member 15 at the tip of a rod separately provided on the side of the guide shaft 9. Furthermore, the press attachment 5 is automatically inserted into and removed from the space 13 using a rotatable cylinder 20. However, as shown in the figure, pins 17 are inserted in two rows 10 into the three rows 10 stages of through holes 6 of the pressing attachment 5.
When the pushing body 10 is lowered with the pressing attachment 5 installed in the space 13, the mandrels 11, 11a, etc. are lowered accordingly, and the expanded pipes arranged below are lowered. The two rows of mandrels 11, 11a that come into contact with the two rows of pins 17 close the openings of the tubes 16, 16a by the pressing force of the pins 17. Press fit into the tube 1
6 and 16a will be expanded respectively. In addition, during the pipe expansion work, since the step part 2 of the pin comes into contact with the lower step part 7 of the pressing attachment 5, a very large force is applied to the mandrel 11 without causing any displacement of the pin in the vertical direction. It is possible to press... On the other hand, since no pin 17 is attached to the mandrel through hole 6 of the pressing attachment 5 located above the mandrel 11b, the fin 18 fitted horizontally into the tubes 16, 16a to be expanded is The fins 18 are attached to the mandrel 1 by simply abutting the tips and passing the upper portions through the mandrel through holes 6.
This avoids a situation in which it is unduly pressed and bent by 1b.

Therefore, in this embodiment, the replacement pin 17
By sequentially changing the mounting position of the pressure attachment 5 in the through hole 6 of the pressure attachment 5, the same pressure attachment 5 can perform all pipe expansion operations within the arrangement range of 3 rows and 10 stages. Furthermore, the work of replacing the replacement pin 17 can be carried out extremely easily by separating the upper and lower members 5a, 5b of the pressing attachment 5 and attaching and detaching the C-shaped retaining ring 3.

In the above embodiment, the locking body for locking the pin body to the pressing attachment is configured with a C-shaped retaining ring, but the present invention is not limited to this, and other ring bodies or A partially cut-out ring body or other various configurations can be used, and the specific configuration is not critical.

Also, regarding the specific configuration of the pin body and the flange-like stepped portion, one pin body is formed so as to be able to be fitted into the mandrel penetration hole of the pressing attachment,
Further, the other flange-shaped stepped portion may have a larger diameter than the pin body and be formed so as to come into contact with the lower step portion 7 formed at the lower part of the mandrel penetration hole, and its specific shape, material, etc. The design can be changed arbitrarily.

In addition, it goes without saying that the gist of the present invention is a replacement pin for attachment to the mandrel penetration hole of a pressing attachment, and does not concern the specific configuration of the attachment or the tube expansion device itself that uses the attachment. .

(Effects of the invention) As described above, the exchange pin according to the present invention is attached to the mandrel penetration hole of the pressing attachment, and by changing the arrangement of the attachment in various ways, the exchange pin according to the invention In order to be able to freely change the arrangement of the holes into various patterns in accordance with the arrangement of the pipes to be expanded, a large number of attachments are prepared that correspond to the various arrangements of the pipes to be expanded, as in the past. There is a particular advantage in that there is no need to keep the pressure attachments in place, the number of pressure attachments to be prepared can be kept to a minimum, and the cost of such attachments can be significantly reduced.

Furthermore, according to the present invention, the number of pressing attachments can be reduced as described above, so
In addition to the problem of storage space for the attachments, problems such as selection errors when selecting attachments corresponding to the arrangement of pipes to be expanded from among a large number are also solved, and the workability of this type of pipe expansion work is improved. have real benefits.

[Brief explanation of the drawing]

FIG. 1 is a front view showing one embodiment of the replacement pin according to the present invention. Figures 2 and 3 show examples of its use, Figure 2A is a plan view showing the replacement pin attached to the press attachment, and Figure 2B is an enlarged cross-sectional view taken along line A-A of Figure 2A. , FIG. 3 is a sectional view of the main part showing the tube expansion device. 1... Pin body, 2... Step part, 3... Locking body,
5... Pressing attachment, 6... Mandrel penetration hole.

Claims (1)

[Scope of utility model registration request] Mandrel penetration hole 6 of press attachment 5
A pin body 1 is formed so as to be able to be fitted into the pin body 1, and a lower step part 7, which is provided at one end of the pin body 1 and has a larger diameter than the pin body 1, is formed in the lower part of the mandrel penetration hole 6. A flange-shaped stepped portion 2 formed;
It is characterized by comprising a locking body 3 which is separately provided on the pin body 1 and locks the pin body 1 to the pressing attachment 5 when the pin body 1 is inserted into the mandrel penetration hole 6. Replacement pin for pressure attachment of tube expansion mandrel.