JPS6220549Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field This invention relates to a drilling cutter used for drilling holes in concrete walls of buildings, etc.

Prior Art Conventionally, when drilling in reinforced concrete and reinforced concrete blocks, the drilling work was carried out by attaching a drilling cutter to a hammer drill and rotating the drilling cutter while vibrating in the drilling direction. However, when this drilling cutter hits the reinforcing steel, as shown in FIG.
A body 3 supporting a carbide chip 1 as shown in the figure
There are cases where the edge hits the reinforcing bar 2 directly, and in the latter case, the reinforcing bar 2 cannot be cut. Therefore, since the carbide tip 1 cannot always cut the reinforcing bar 2 by impact, it takes a long time to cut the reinforcing bar 2 with this drilling cutter, and the carbide tip 1 cannot cut the reinforcing bar 2 by impact.
The side surface 1a of the carbide chip 1 was hit hard by the reinforcing bar 2.
There were drawbacks such as chipping and peeling from the body 3.

Therefore, a drilling cutter was proposed in which the number of carbide tips 1 was increased and the interval between the tips 1 was narrowed to make it easier for the carbide tips 1 to hit the reinforcing bar 2. However, by increasing the number of carbide tips 1, each tip 1 The impact force of the hammer drill acting on the tip is dispersed and weakened, resulting in an unreasonable situation in which the ability to drill into concrete is reduced.

Purpose This invention was made in order to overcome the drawbacks of conventional drilling cutters as described above, and its purpose is to provide a drilling cutter that can quickly drill holes in reinforced concrete.

Embodiment An embodiment embodying this invention will be described below with reference to the drawings. Reference numeral 11 indicates a perforation cutter;
A spiral groove 12a is formed on the outer peripheral surface of the body 12, which is formed into a cylindrical shape with a bottom, and a shank 13 is screwed onto the bottom surface of the spiral groove 12a. Reference numeral 14 denotes a center pin with a built-in spring that is inserted and fixed at the center of the tip of the shank 13, and its tip protrudes slightly from the tip edge of the body 12 so that the center of the body 12 can be positioned.

Reference numeral 15a is a carbide tip that serves as a cutting edge brazed to the periphery of the tip of the body 12 at equal intervals, and in the middle of each of the carbide tips 15a is a carbide tip whose cutting edge is set back about 1 to 2 mm from the tip 15a. A hard chip 15b is also brazed.

Next, the perforating cutter 11 configured in this way
Explain the effect of

Now, attach the base end of the shank 13 of this drilling cutter 11 to the hammer drill, align the tip of the center pin 14 with the center of the drilling position in the concrete wall, etc., and in this state operate the hammer drill to vibrate the body 12 in the drilling direction. When the body 12 is rotated while rotating, the center of rotation of the body 12 is positioned by the center pin 14 while drilling is performed. When cutting concrete, only the leading carbide tip 15a comes into contact with the cutting surface, so the impact force of the hammer drill is dispersed to the carbide tip 15b and acts only on the carbide tip 15a without being weakened.

On the other hand, as shown in FIG. 4, when cutting the reinforcing bars 2 in concrete, a carbide tip 15b is provided between the carbide tips 15a to cut the reinforcing bars 2.
Since the reinforcing bar 2 can always be cut by impact with both tips 15a and 15b, the impact force of the hammer drill can be efficiently used to quickly cut the reinforcing bar 2.

Therefore, if this drilling cutter 11 is used to drill a hole in reinforced concrete or a block containing reinforcing bars, the concrete part can be quickly cut with the carbide tip 15a as in the conventional method, and the reinforcing steel can be cut with the carbide tips 15a and 15b. 2 can also be cut quickly.

Effects As described above, in this invention, a plurality of cutting blades 15a are provided at regular intervals on the periphery of the tip of the bottomed cylindrical drilling body 12, and a tip is placed in the middle of the cutting blade 15a. By providing the cutting blades 15b that are further set back, an excellent effect can be achieved in that reinforced concrete and reinforced concrete blocks can be drilled quickly.

[Brief explanation of the drawing]

Figures 1 and 2 are explanatory diagrams showing the cutting state of reinforcing bars by a conventional punch cutter, Figure 3 is a front view showing an embodiment of this invention, and Figure 4 is a diagram showing the cutting state of reinforcing bars by a conventional punch cutter. It is an explanatory view showing the cutting state of reinforcing bars. Body...12, cutting blade...15a, 15b.

Claims (1)

[Scope of utility model registration request] A plurality of cutting blades 15a are provided at regular intervals on the periphery of the tip of the bottomed cylindrical drilling body 12, and a cutting blade 15b whose tip is set back from the tip of the cutting blade 15a is provided in the middle of the cutting blade 15a. A perforated cutter characterized by: