JPH11320223A - Method for boring plate and boring work machine therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform boring of a plurality of plates simultaneously with chamfering of their obverse and reverse edges. SOLUTION: A plurality of plates 30 are laminated while certain gaps are reserved by interposing spacers 21 between them, and are fixed to a boring machine. A drill D is fitted with a chamfering tip 12, which protrudes triangularly from the drill surface in the axial direction of the drill D, and the side edges of the protruding triangle piece work as chamfering blades to chamfer the peripheral edge of the bored hole, and retracts into the drill D with a requisite pressing force. The drill D pierces the plates from one surface to the other to produce holes 4, and the hole edge on one surface of each plate is chamfered by the tip 12 (a), and when the drill D is drawn off from the plates, the hole edge on the other surface of each plate is chamfered 4b by the tip 12 (b). Thus the boring 4 and chamfering 4b are performed simultaneously.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drilling method and a drilling machine for simultaneously drilling and chamfering a plurality of plate-like objects such as steel plates.

[0002]

2. Description of the Related Art Normally, when a workpiece is perforated, a return due to cutting occurs at an edge (peripheral edge) of the perforation, and yarn chamfering is performed to remove the return. In a typical method, an operator grinds and chamfers with an air grinder or a file. As a mechanical method, a drill of a drilling machine such as a radial drilling machine is used as a stepped drill P as shown in FIG. 5, and a hole is drilled at a small diameter portion 1 and a yarn chamfer is formed at a large diameter portion 2 at the same time. Yes, JP-A-4-53613, JP-A-4-7900
No. 5, gazette.

[0003] In a bridge structure, for example, as shown in FIG. 6, there is an attachment plate 3 as a member for connecting the I-girder W and the base material of the bridge girder. This attachment plate 3 must be formed with a plurality of holes 4 for mounting through a high-tensile (high-tensile steel) bolt, and the same shape and the same number of bolt holes 4 are provided at the same position. After the contact plates 3 are stacked and drilled (after the holes 4 are drilled), the peripheral edges of both openings (front and back openings) of the hole 4 are chamfered.

Here, both edges of the opening of the hole 4 of the attachment plate 3 must be chamfered, as shown in FIG.
When the return 4a occurs on the periphery of the opening, the attachment plate 3 and the spar W
This is because there is an inconvenience that a gap occurs because the ribs do not adhere to each other. For example, the attachment plate 3 and the base material W by fastening the bolt 5
If the frictional force is insufficient, the connection between the attachment plate 3 and the base material W is loosened, causing vibration and causing a catastrophic event in the case of an earthquake. Further, there is a possibility that the bolt 5 swings under the influence of vibration or the like due to the running of the car. Further, rust is generated in the gap, and corrosion proceeds. This is a problem especially when the bridge is installed near the sea or the bay. Further, the operator may be injured by the return 4a of the cutting. For this reason, the thread chamfering (both front and back) of the bolt hole 4 of the attachment plate 3 must be ensured so that no gap is formed (close contact).

[0005] Also, the entire bridge is coated with rust-preventive paint.
As shown in FIG. 8A, if there is a return 4a in the hole 4, the coating 4a is not surely performed on the portion 4a and causes rust. Therefore, as shown in FIG. This is also for the purpose of performing 4b to surely paint the periphery of the hole opening.

[0006]

SUMMARY OF THE INVENTION The above stepped drill P
Can be chamfered only on the surface (front surface) facing the processing direction of the drill, and the chamfering on the back surface requires reversal of the workpiece (steel plate 3), and can only be machined one by one. In addition, when simultaneously drilling multiple steel sheets, the top steel sheet can be chamfered, but the bottom steel sheet can only be drilled. Must. However, in actual work, a plurality of steel plates are simultaneously drilled, and then the steel plates are chamfered while being inverted one by one.

In addition, manual beveling with an air grinder or the like is performed by inverting the front and back surfaces of a steel sheet for each sheet.

In any case, chamfering with reversal of each steel sheet is a very troublesome operation, and the reversal operation involves danger.

An object of the present invention is to improve the workability of drilling and chamfering a plate-like object such as a steel plate under the above circumstances.

[0010]

In order to solve the above-mentioned problems, the present invention firstly stacks a plurality of plate-like members and drills them from one surface side of the layer in order to enhance the piercing property. It was decided. Next, in order to be able to perform chamfering on the front and back sides of each plate-like body, a gap was formed by interposing a spacer between each plate-like body. The chamfering jig can be located in the gap to perform return cutting, and chips can be removed to the gap. Then, the drilling operation and the chamfering of the drill are performed simultaneously in one drilling operation of the drill.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a preferred embodiment according to the perforation method of the present invention, a plurality of plate-like objects are stacked with a required gap secured therebetween by interposing a spacer between the plate-like objects. The plate-like object is fixed to a drilling machine, and a drill having a chamfering tip is cut and penetrated from one surface of the stacked plate-like object group to the other surface to pierce each plate-like object. Chamfering the perforated edge on the one surface side of the plate-like material with the chamfering tip,
When the perforating drill is pulled out from the group of plate-like objects, a configuration may be adopted in which drilling and chamfering are performed simultaneously by chamfering the perforated edge of the other surface of each plate-like object with the chamfering chip.

[0012] As a drilling machine capable of performing this drilling method, a drill having a chamfered tip provided in the drilling machine is characterized in that the chamfered tip protrudes triangularly from the drill surface in the axial direction of the drill, and both sides of the protruding triangular piece. It is possible to adopt a configuration in which the edge becomes a chamfering blade to chamfer the perimeter of the perforation and to retreat into the drill with a required pressing force.

[0013]

FIG. 1 shows an embodiment of a drill D, and FIG.
4 to 4 show an embodiment of a drilling operation (method) using the drill D. The drill D is, as shown in FIG.
A hole 11 is formed in the screw portion 10, and a triangular plate-shaped chamfering chip 12 is rotated through this shaft 11 through a shaft 13 (undulation).
As shown in FIG. 3B, the tip 12 is always attached by the torsion spring 14 while being freely attached.
Are positioned so that the corners protrude.

In this state, as shown in FIG. 2, when the drilling operation is performed, the chip 12 in contact with the peripheral edge of the hole of the plate 30 is chamfered by the lower edge blade (FIG. 2B). When the drilling further proceeds, due to the advancing pressing force, as shown in FIG. 3C, it retreats into the hole 11 against the spring 14, and after leaving the drilling 4, again as shown by the solid line by the spring 14. It stands up and returns (FIG. 4D). For this reason, when pulling out while rotating the drill P from the drilling,
The tip 12 retreats into the hole 11 while the upper edge blade performs the chamfering 4 b on the back surface of the hole 4, and comes out of the hole 4. By this operation, the front and back chamfers 4b are performed simultaneously with the perforations 4.

Next, the operation of simultaneously piercing a plurality of steel plates 30 such as the attachment plate 3 and chamfering the front and back sides will be described. First, as shown in FIGS. The required number of sheets are stacked on the receiving plate 21 of the surface plate 20 with spacers 22 interposed therebetween, with a gap of about 10 mm, and fixed by the clamp 23. In the figure, reference numeral 24 is a reference pin.

Next, as shown in FIG. 4, when the above-mentioned drill D is used for drilling, each of the steel plates 3
At 0, drilling 4 and chamfering 4b on the front side are performed, and after drilling of all the steel plates 30 is completed, when the drill D is pulled out while rotating as shown in FIG. Chamfering 4b on the back side of the steel plate 30 is performed.
It is sufficient that the chamfer 4b is about 0.5 to 1.0c, and the chip 12 is sufficiently cut (chamfer 4b).
Could be performed.

[0017]

As described above, according to the present invention, the front and back chamfers can be performed simultaneously with the perforation of a plurality of plate-like bodies.
The workability of chamfering and drilling is improved.

[Brief description of the drawings]

1A and 1B show an embodiment of a drill; FIG. 1A is a front view, and FIG.

FIG. 2 is a diagram illustrating the operation of the embodiment.

FIG. 3 is a perspective view of one embodiment of a perforation method.

FIG. 4 is a diagram illustrating the operation of the embodiment.

FIG. 5 is a front view of a conventional chamfering drill.

FIG. 6 is a partial perspective view of an I-girder of a bridge.

FIG. 7 is a sectional view of a bolted portion of FIG. 6;

FIG. 8 is an explanatory drawing of painting.

[Explanation of symbols]

 Reference Signs List A drilling machine D drilling drill with chamfering tip P drilling drill W bridge I-girder 3 attachment plate 4 bolt hole 4a cutting return 4b chamfering 10 drill screw part 11 tip hole 12 chamfering tip 13 tip shaft 14 torsion spring 30 steel plate

Claims (2)

[Claims] 1. A plurality of plate-like objects 3 and 30 are laminated with a required gap secured therebetween with a spacer 22 interposed between the plate-like objects, and the plurality of plate-like objects are passed through a punching machine A. A fixed and perforated drill D having a chamfering tip 12 is cut and penetrated from one side of the laminated plate group toward the other surface to form a hole in each plate, and the one side of each plate is formed. The chamfering tip 12 chamfers the piercing edge of the
A method for punching a plate-like object, wherein when the sheet is pulled out from the plate-like object group, the perforated edge on the other side of each plate-like object is chamfered by the chamfering tip 12 and the chamfering is performed simultaneously. 2. A boring machine A for performing the method for boring a plate-like object according to claim 1, wherein the chamfering chip 12 is provided.
The chamfering tip 12 is provided with a drill D
In the axial direction, it protrudes from the drill surface in a triangular shape, and both side edges of the protruding triangular piece become chamfering blades to chamfer the perimeter of the drilling hole, and retreat into the drill D with a required pressing force. A drilling machine for simultaneously drilling and chamfering a plurality of plate-like objects.