JPS5843207B2 - A device that forms a slit at the end of a pipe - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for forming a slit at the end of a pipe,
In particular, the present invention relates to an apparatus suitable for efficiently forming a large number of slits.

FIG. 1 is a diagram for explaining the invention in detail,
FIG. 2 is a perspective view of a pipe with a slit formed at the end of the pipe.

A pipe 1 shown here is used as a gas ejection port of a gas burner, and a plurality of slits 3, for example, eight slits, are formed at an end 2 of the pipe, distributed in the circumferential direction.

Conventionally, as a method of forming such a slit 3,
A female die was inserted into the pipe end 2, and the pipe was cut from the outside with a punch.

In this method, the chips are brought to the female mold side, so the female mold needs grooves to receive the chips, but a large number of grooves, for example eight, are formed on the outer periphery of the female mold. This is extremely difficult due to problems in the strength or design of the female mold, so it has been possible to form only a small number of grooves, about two at most, in the female mold.

Therefore, when forming eight slits, for example, the only method that can be applied is to form the slits sequentially in the circumferential direction of the pipe end 2 using the indexing method, which has the drawback of poor efficiency.

The main object of the invention is therefore to provide a device for forming slits in pipe ends, which makes it possible to eliminate the above-mentioned disadvantages.

Another object of the present invention is to provide an apparatus that can form a slit at the end of a pipe with light force.

Other objects and features of the present invention will become more apparent from the detailed description given below with reference to the drawings.

FIG. 2 is a sectional view showing an embodiment of the present invention.

FIG. 3 is a longitudinal sectional view showing the punch of FIG. 2, and FIG. 4 is a bottom view of the same.

FIG. 5 is an interplanar view of a portion of the die of FIG.

FIG. 6 is a sectional view showing a slit forming process using a punch and a die.

In FIG. 2, the left half shows the punch etc. in the upper position, and the right half shows the punch etc. in the lower position.

Mainly referring to FIG. 2, a ram attachment hole 5 is formed in the upper plate 4, and the upper plate 4 is attached to a ram (not shown) through this hole 5.

A backing plate 6 is embedded in the lower surface of the upper plate 4, and a punch 7 is disposed in contact with this backing plate 6.

The punch 7 is fixed to the upper plate 4 by a punch plate 8 fixed to the upper plate 4.

A holder 9 is provided to protrude from the lower surface of the punch plate 8.

A die 10 is held by this holder 9.

The die 10 is held in the holder 9 between the position 1 where it contacts the punch plate 8 (right side in FIG. 2) and the position 1 where it contacts the locking part 11 of the holder 9 (left side in FIG. 2). ,
It can be slid up and down.

A compression spring 12 as an elastic means is built into the punch plate 8, and the die 10 is constantly urged downward.

An outer cam 13 is also provided on the lower surface of the upper plate 4 and projects downward.

An inclined surface 14 is formed at the lower end of the outer cam 13.

All of the above-mentioned components follow the vertical movement of the upper plate 4.

Components arranged below the above-mentioned components will be explained.

A heel 16 is provided on the upper surface of the die set 15.

A bolt 17 is disposed through the heel 16 in a lateral direction so as to be slidable on the heel 16.

The tip of the shaft portion of the bolt 17 is screwed into the inner cam 18 and fixed to each other.

A washer 19 is arranged in contact with the head of the bolt 17,
A compression spring 20 is inserted between the washer 19 and the heel 16.

As a result, the inner cam 18 is always urged to approach the heel 16, and its terminal end is defined by the spacer 21 disposed on the shaft portion of the bolt 17.

The inner cam 18 is formed with an inclined surface 22 that faces the inclined surface 14 of the outer cam 13 .

The inner cam 18 is separated into left and right parts, and has the function of holding the pipe 1 to be processed when the separated parts come close to each other.

That is, the inner cam 18 functions as a pipe holding means.

Note that the outer cam 13 has a shaft portion of the bolt 17 and a spacer 21 when it moves downward as shown on the right side of FIG.
A recess 23 is formed to receive the.

Next, the punch 7 will be explained in detail with reference mainly to FIGS. 3 and 4.

The punch 7 has a first cutting edge 25 extending in the axial direction and having a surface 24 that slopes inward toward the tip.
Eight protruding pieces are formed distributed in the circumferential direction at angular intervals of .

These eight first cutting edges 25 correspond to the eight slits 3 formed in the pipe end 2 in FIG.

The tip of the punch 7 is selected to have a size that allows it to be inserted into the pipe end 2.

Next, mainly referring to the second interval and FIG.
The details of the configuration of 0 will be explained.

A through hole 26 is formed in the die 10 to surround the pipe end 2 from the outer periphery.

Around this through hole 26, there are eight grooves 2 extending in the radial direction.
7 are formed at angular intervals of 45°.

This groove 27 receives the first cutting edge 25 of the punch 7, and the second cutting edge 25 performs cutting by a new action with the first cutting edge 25.
Both side edges are defined by the cutting edge 28.

Inside the groove 27 is an inwardly inclined surface 2 of the first cutting edge 25 of the punch 7.
4 to form a push-cut edge 29 that performs push-cut.

The shape of the punching edge 29 is best shown in FIG.

The groove 27 is a passageway 3 extending at 1 on the underside of the die 10.
0, and this passage 30 further extends through the inner cam 18.
The passage 31 inside the die set 15 is in a state where it can communicate with the passage 32 inside the die set 15.

In the above configuration, the operation of the apparatus shown in FIG. 2 will be explained below.

The apparatus shown in FIG. 2 is basically constructed so that all operations proceed simply by the downward movement of the upper plate 4.

First, the pipe 1 to be processed is positioned between the pair of inner cams 18.degree. by pressing the button at the initial stage of the downward movement of the upper plate 4.

That is, when the outer cam 13 moves downward with the downward movement of the upper plate 4, the inner cam 18 slides on the die set 15 against the elasticity of the compression spring 20 due to the sliding contact between the inclined surfaces 14 and 22. It is moved to a state where the pipe 1 is sandwiched between the pipes.

This is the state of the inner cam 18 shown on the right side of FIG.

Also, at this stage, at least the pipe end 2 of the pipe 1 is received within the through hole 26 of the die 10.

When the upper plate 4 moves further down, the lower surface of the die 10 comes into contact with the upper surface of the inner cam 18.

If the upper plate 4 moves further down from this state, the compression spring 12
The die 10 and the punch plate 8 come relatively close to each other against the elasticity of the die 10 and the punch plate 8.

Depending on the relative proximity of the punch plate 8, the tip of the punch 7 gradually enters into the pipe end 2.

As the punch 7 enters, a cut is formed in the pipe end 2 by the shearing action of the first cutting edge 25 and the second cutting edge 28, as clearly shown in FIG.

This cut corresponds to 8 slits 3, and 8
Pairs of cuts are formed simultaneously.

Depending on the formation of this notch, strip-shaped chips 3
3 is formed, but the chips 33 are guided by the inwardly inclined surface 24 of the punch 7 and are bent outward.

Furthermore, as the punch 7 advances into the pipe end 2, the punching edge 29 approaches the inwardly inclined surface 24 of the punch 7, and the root of the strip-shaped chips 33 moves toward the punching edge 2.
9 and the inner inclined surface 24, and the strip-shaped chips 33 are separated from the pipe end 2.

This separated strip of chips 33 is discharged from the groove 27 out of the device through a passage 30.degree. 31.32.

In the manner described above, a pipe 1 in which eight slits 3 are formed at the pipe end 2 is obtained.

When the upper plate 4 moves upward, the state shown at the left end in FIG. 2 is reached, and the processed pipe 1 can be taken out.

Then, by loading the pipe 1 to be processed next and repeating the above-described operations, the pipe 1 shown in FIG. 1 can be sequentially and efficiently obtained.

As described above, according to the present invention, the punch is inserted into the end of the pipe and the slits are formed while bending the chips outward, if necessary.

An apparatus capable of simultaneously forming a large number of slits is realized.

Further, even when forming a large number of slits, since no indexing method is applied, the slits can be formed at the end of the pipe accurately and efficiently using a simple device.

Furthermore, since the step of forming a cut for forming a slit utilizes cutting by shearing action, the principle of scissors is applied, and the cut can be formed with a small force.

In addition, since the strip-shaped chips are bent outward, there is no burr on the inner surface of the pipe end when forming the slit, and special processing to remove such burrs is not required. Even without it, fluids such as gas can flow smoothly.

In addition to the above-mentioned punch and die, the present invention also includes an elastic means such as a spring that maintains the punch and die in a spaced relationship at all times, and the punch resists the elasticity of the elastic means. Since the punch is close to the die, it is only necessary to apply an external force to the approaching/separating movement between the die and the punch, and only to remove this force for the separating movement.

Therefore, the driving means for moving the die and punch closer to each other and farther apart becomes simple.

In addition, although the above-mentioned embodiment was described in relation to an apparatus that forms eight slits at the same time, it is not limited to this, and may be used when forming other numbers of slits or when forming only one slit. This invention is equally applicable to

[Brief explanation of the drawing]

FIG. 1 is a diagram for explaining the invention in detail,
FIG. 2 is a perspective view of a pipe with a slit formed at the end of the pipe. FIG. 2 is a sectional view showing an embodiment of the present invention. FIG. 3 is a longitudinal sectional view showing the punch of FIG. 2, and FIG. 4 is a bottom view of the same. FIG. 5 is a plan view of a portion of the die of FIG. 2. FIG. 6 is a sectional view showing a slit forming process using a punch and a die. In the figure, 2 is a pipe end, 3 is a slit, 7 is a punch, 9 is a holder as a holding means that can be brought close to and separated from it, 10 is a die, 18 is an inner cam as a pipe holding means, and 24 is shown inward toward the tip. Inner inclined surface as inclined surface, 25
is the first cutting edge, 26 is the through hole, 27 is the groove, 28 is the second cutting edge,
29 is a press cutting edge, and 33 is a strip-shaped chip.

Claims (1)

Claims: 1. A means for holding the pipe; and a first cutting edge having a surface extending in the axial direction and sloping inwardly toward the tip is formed projecting from the curved surface. With a punch that can be inserted into the end of the pipe. a groove whose side edges are defined by a second cutting blade that receives the first cutting blade and performs cutting by a perforation action with the first cutting blade; and the inclined surface of the first cutting blade located within the groove. and a die that surrounds the pipe end from the outer periphery, and includes a push-cutting edge that performs push-cutting. The punch and the die are provided with means for holding the punch and the die so as to be close to and separate from each other, and the holding means capable of being close to and separate from each other further includes elastic means for holding the punch and the die in a positional relationship that is always separated from each other. When the punch approaches the pipe holding means integrally with the die, the die comes into contact with the pipe holding means, so that the die approaches the punch against the elasticity of the elastic means. Configured. A device that forms a slit at the end of a pipe. 2. The first cutting edge, the second cutting edge, and the push cutting edge are arranged in plural sets distributed in the circumferential direction of the pipe end. An apparatus for forming a slit in a pipe end according to claim 1.