JPS62263832A - Piercing punch for pipe piercing - Google Patents

Abstract

PURPOSE:To prevent the deformation of a pipe by providing a pair of tip blade parts opposing point symmetrically on the punch main body, forming two pairs of lead blade parts with the tip end blade part as the apex and arranging the groove part for insulation between the lead blades. CONSTITUTION:A pair of tip blade parts 12, 13 are provided at the tip of a punch main body 11 and two pairs of lead blade parts 14, 15, 16, 17 descending toward the side part respectively with those as the apex are formed as well. The groove part 18, 19 for insulation are respectively arranged between the lead blade parts 14, 17 and 15, 16. When a piercing punch 5 is descended to a set pipe 1, the tip blade part 12 is first cut by a cutting blade 20, the blade part 13 is then cut. In succession, the lead blade parts 14-17 are cut in order. In this case, the loading of a load is prevented on the same place in parallel to the axial line 37 of the pipe 1. Consequently the deformation of the pipe 1 is prevented.

Description

Detailed Description of the Invention A1 Objective of the Invention (1) Industrial Field of Application The present invention relates to pipe piercing earrings for drilling a circular hole in the wall of a pipe having a circular cross section in a direction perpendicular to the axis of the pipe. Regarding punch.

(2) Prior art Conventionally, such piercing punches have been used, for example, in Japanese Patent Publication No. 55-1
This method is known from Japanese Utility Model Publication No. 1413 and Japanese Utility Model Publication No. 60-25306.

(3) Problems to be Solved by the Invention However, in the conventional punch body described above, the lead blades on both sides of the pair of tip blades located symmetrically with respect to the axis of the punch body are formed in the same shape, and both end blades Piercing is performed by placing the lead blades on the same generatrix of the pipe, and at this point the lead blade is applying a load to the wall of the pipe on the same plane parallel to the axis of the pipe, causing the pipe to deform. The problem is that it is easy to do.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a piercing punch for punching a pipe that can prevent deformation of the pipe.

Structure of B0 invention! 11. Means for Solving the Problems According to the present invention, a punch body having at least a cylindrical tip portion has a pair of tip blade portions facing each other at points symmetrical positions with respect to the axis of the punch body;
There are two pairs of lead blades that extend downward to both sides with the tip blades as the top, and a groove that insulates between the circumferentially adjacent lead blades. portions are formed with cutting edges on their outer peripheries;
The lead blades on both sides of each groove have mutually different shapes.

(2) During piercing, both tip blades start cutting into the wall of the pipe, and then cutting is performed by the lead blade, but both the tip blade and the lead blade have cutting edges on their outer peripheries. Moreover, since the reed blades on both sides of the groove are formed in different shapes, the load acting on the pipe wall due to each reed blade is shifted in the direction perpendicular to the axis of the pipe. Deformation of the pipe is prevented as much as possible.

(3) Embodiment An embodiment of the present invention will be described below with reference to the drawings. First, in FIGS. 1 and 2, the lower half of the pipe 1 to be drilled is fixed! ! It is fitted into and placed in a mounting groove 3 with a semicircular cross section provided on the mounting table, and the elevating body 4, which can be raised and lowered above the mounting table 2, has a structure for making holes in the wall of the pipe 1. The piercing punch 5 is attached facing downward. In addition, a puff door having a pressing groove 6 having a semicircular cross section that fits into the upper half of the pipe 1 is supported on the elevating body 4 via a spring 8 and a bolt 9, and the pad 7 has a limited range. Up and down relative movement with respect to the elevating body 4 is permitted. Moreover, a through hole 10 extending vertically is formed in the pad 7 for inserting the piercing punch 5, and as the elevating body 4 further descends while holding the pipe l with the pad 7, the piercing punch 4 is inserted. The pipe 1 is drilled by descending downward into the through hole 10.

In FIGS. 3, 4, 5, and 6, the piercing punch 5 includes a pair of tip blades 12, 13 at the tip of a punch body 11 whose tip is at least cylindrical. two pairs of reed blade parts 14, 15; 16, 17 that descend toward the respective dangling sides with the top part as the top, and a groove part 18.19 that insulates between the reed blade parts 14, 17i15.16 adjacent in the circumferential direction. It consists of

Referring also to FIG. 7, which is a developed view of the inner periphery of the tip of the punch body 11, both tip blade portions 12 and 13 are provided facing each other at point-symmetrical positions with respect to the axis of the punch body 11, It has cutting edges 20, 21 on the outer peripheral edge, and blade surfaces 22, 23 that are inclined inward from the cutting edges 20, 21 toward the axis of the punch body 11. Moreover, one of the leading edge portions 12 is formed with a larger protrusion amount along the axis of the punch body 11 than the other leading edge portion 13.

Each lead blade part 14, 15, 16, 17 has a cutting edge 25, 26, 27, 28 on its outer periphery, and is convex outward and becomes inner as it goes toward the groove part 18, 19 side. Curved blade surfaces 29, 30.3 inclined in the direction
1.32 respectively. Moreover, the lead blade portions 14, 17; 15, which sandwich the groove portions 18, 19 therebetween;
The shapes of 67 are different from each other. For example, the tip blade portion 12
The right-hand lead blades 15, 17 at 13 degrees are connected to the tip end blade 12.13 more gently than the left-hand lead blade 14.16.

On the inward side of the blade surface 22 of the tip blade part 12, a surface ridge 33 is formed which is inclined about 1 to the lead blade part 15 side, and the tip blade part 1
3, a chamfer 34 is formed on the inner side of the blade surface 23, which is inclined toward the beaded blade portion 17 side.

The groove portion 18.19 is connected to the adjacent lead blade portion 14゜17;1.
5 and 16 so that the inner ends of the lead blade parts 14 and 15 are located further outward in the axial direction of the punch body 11 than the inner ends of the lead blade parts 16 and 17. A groove 18. between the inner ends of the lead blade parts 14, 17i15, 16.
19 are provided. Furthermore, cutting edges 35,36 are also provided at the outer edges of the grooves 18,19.

Such a piercing punch 1 is attached to the elevating body 4 so that the straight line connecting the two tip end portions 12 and 13 is parallel to the axis of the pipe 1 placed on the mounting table 2.

Next, the operation of this embodiment will be explained with reference to FIG.
It is placed on the mounting table 2 below. Therefore, when the elevating body 4 is lowered, the pad 7 comes into contact with the upper part of the pipe 1, and when the elevating body 4 is further lowered, the pad 4 is pressed against the pipe 1 by the elastic force caused by the contraction of the spring 8, and the pad 7 contacts the upper part of the pipe 1. is fixed.

When the elevating body 4 is further lowered, the piercing punch 5 descends inside the through hole 10, the tip blade portion 12 first contacts the upper outer surface of the pipe 1 on one side of the generatrix 37, and the cutting edge 20 punches the pipe 1.
Then, on the other side of the base i & 1137, the tip blade portion 13 comes into contact with the upper outer surface of the pipe 1, and the wall portion of the pipe 1 is cut with the cutting blade 21. By cutting into the wall of the pipe l with the tip blades 12 and 13 at different times in this way, each cutting action is performed powerfully. In addition, the connecting parts between the tip blade parts 12, 13 and the lead blade parts 14, 15; 16, 17 on both sides are asymmetrical and are almost symmetrical with respect to the axis of the punch body 11, so that the cutting part is balanced. Moreover, since the loads of the tip blades 12 and 13 on the pipe 1 do not act on the same generatrix 37, a large load does not act on the pipe 1 along the generatrix 37.

After cutting with the tip blade parts 12 and 13, each lead blade part 1
The wall portion of the pipe 1 is cut into a circular shape by the cutting action of the cutting blades 25 to 28 of 4 to 17.

At this time, the blade surfaces 29 to 32 of each lead blade part 14 to 17 are inclined inward, and the outer peripheral edge of the cut scrap is pressed by each of the blade surfaces 29 to 32, deforming inward. go.

When the inner ends of the lead blades 14 to 17 come into contact with the outer surface of the pipe 1, the scraps bite into the grooves 18.
19 and cut by cutting blades 35 and 36.

When cutting with each lead blade part 14 to 17, each groove part 18
, 19, the shapes of the lead blades 14, 17; 15, 16 on both sides of the pipe 1 are different, so that no load is applied to the pipe 1 on the same plane parallel to the axis of the pipe 1, and the deformation of the pipe 1 is prevented. will be prevented as much as possible.

In the embodiments described above, one of the leading edge portions 12 is made to protrude more than the other of the leading edge portions 13, but the axial positions of both of the leading edge portions 12 and 13 may be the same.

Furthermore, the grooves 18 and 19 are effectively used as tool escapes during grinding of the lead blades 14 to 17.

C0 Effects of the Invention As described above, according to the present invention, a punch body having at least a cylindrical tip has a pair of tip blades facing each other at points symmetrical positions with respect to the axis thereof, and a pair of tip blades having the tip blades as the top. Two pairs of reed blades descending toward both sides and a groove insulating between circumferentially adjacent reed blades are provided, and both tip blades and each lead blade have cuts on their outer peripheries. The lead blades on both sides of each groove have different shapes, so the deformation of the pipe is minimized by avoiding loads acting on the pipe on the same plane parallel to the axis of the pipe. It can be prevented.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and Fig. 1 is a longitudinal side view of a processing machine equipped with the pierce punch of the present invention, and Fig. 2 is a front view of the notch seen from the direction of the arrow ■ in Fig. 1. Figure, 3rd
The figures are side views of the piercing punch, figures 4, 5 and 6.
The figures are views in the direction of arrows ■, ■, and ■ in FIG. 3, FIG. 7 is a developed view of the inner periphery of the tip of the punch body, and FIG. 8 is a plan view showing the positional relationship between the pipe and the piercing punch. 1...pipe, 5...piercing punch, 12.13.
...Tip blade part, 14-17...Lead blade part, 18.1
9... Groove, 20, 21. 25-28... Cutting edge
Applicant: Honda Motor Co., Ltd.
Honda Ingeni 7 Resig Co., Ltd. Figure 7 Figure 8 Figure 2 Figure 1 Figure 5 Figure 4 Figure 3

Claims (3)

[Claims] (1) A punch body with at least a cylindrical tip,
A pair of tip blades face each other at points symmetrical positions with respect to the axis, two pairs of lead blades descend toward both sides with the tip blades as the apex, and a pair of lead blades that are adjacent to each other in the circumferential direction. an insulating groove, both tip blades and each lead blade are formed with cutting edges on their outer peripheries, and the lead blades on both sides of each groove have mutually different shapes. Piercing punch for piercing pipes. (2) Each of the tip blade portions is formed to be inclined inward as it goes toward the axis side of the punch body, and each lead blade portion is formed to be convex toward the outside and to be inclined inward as it goes toward the groove side. A pierce punch for punching a pipe according to claim 1, characterized in that it is formed in a curved shape that is inclined to . (3) The two tip end blade portions are provided on the punch body at different positions along the axis of the punch body. Piercing punch for piercing pipes.