JPH06212872A - Excavation bit - Google Patents

Abstract

PURPOSE:To prevent the inflow of gravel, oil, etc., enhance the excavation and boring work efficiency by providing a check valve in the middle part of a blowing air way provided to the inside of a bit body or the inside of an additional part combined with the bit body. CONSTITUTION:A check valve 4 is provided to the upper part of an air way 3 of a bit body 2. At that time, a cylindrical valve body 5 is fitted to a cylindrical body mounted to the inside of an air way 3 in a slidable manner, and a spring 8 for biasing the valve body 5 toward a valve seat is provided to the cylindrical body 6. When a compressed air is supplied to the air way 3, a cylindrical section of the valve body 5 is pushed down, and it is blown out from an injection port 13. When the compressed air is not supplied, the cylindrical section of the valve body 5 is pushed against the valve seat 7 by the biasing force of the spring 8, and the inflow of earth, etc., into a rotary striking device is prevented. According to the constitution, damage in the rotary striking device, performance deterioration and no-operation are prevented, and the work efficiency can be promoted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rock drilling machine, down-the-hole hammer, and other excavating bits for use in earthmoving and rock excavating civil engineering and construction work such as anchor holes, boring holes, and blast holes. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drill bit and a drill (hereinafter collectively referred to as a drill bit).

[0002]

2. Description of the Related Art A conventional drill bit has a tip and a tool made of a super hard material for underground drilling and rock drilling at the tip of the bit body (holder), and compressed air is allowed to pass inside the bit body. An air passage is provided for blowing air from the tip. This drill bit is often attached to a rotary hammering device that operates with compressed air, and is struck by the rotary hammering device, and the entire bit is rotated, so that the tip / cutting tool at the tip of the drill bit excavates underground / rock. Perforate. Further, the air that has passed through the air passage is ejected to the tip of the drill bit to clean the portion to be drilled and to cool the tip portion of the drill bit that becomes hot.

[0003]

In the conventional excavating bit, when the excavation work is interrupted / finished and the supply of the compressed air sent to the air passage in the bit body is stopped, the excavation in the ground, rock or water is performed. From the compressed air outlet at the tip of the bit, pebbles, chips, rock powder, earth and sand, muddy water, oil, etc. flow into the air passage inside the drill bit, and further enter into the mechanism of the rotary impacting device and rotate. The percussion device was damaged, rendered inoperable or degraded. If the compressed water is sent to the air passage, the inflowing water can be easily discharged to the outside and blown off, and even if it remains to some extent, it does not significantly affect the rotary striking mechanism. However, if sand, mud, clay, rock powder, oil, etc., flow into and remain inside the rotary impact mechanism, it will seriously damage the rotary impact mechanism and render it inoperable. Repairing this rotary impact mechanism was difficult and time consuming. Moreover, the excavation / drilling work was interrupted, resulting in poor work efficiency.

In order to solve these conventional problems,
Some have adopted a method of providing a check valve in the air passage inside the rotary striking device. However, even with this method, pebbles, chips, rocks,
Since dirt, muddy water, etc. enter, the rotary impact mechanism of the rotary impact device cannot be sufficiently protected. or,
Once these flow into and become inoperable, the entire rotary percussion device or an important part of it must be replaced, the excavation work is interrupted for a long time, and the repair cost is increased. In addition, repair and replacement of parts for the check valve failure in the rotary impact mechanism are troublesome.

The problem to be solved by the present invention is to solve these problems of the prior art and prevent the inflow of pebbles, chips, rock powder, earth and sand, muddy water, oil, etc. into the rotary impact device. The present invention provides a drilling bit that prevents damage, deterioration, and operation stoppage, and can quickly and easily eliminate clogging, thereby improving work efficiency of drilling and drilling work.

[0006]

SUMMARY OF THE INVENTION The gist of the present invention, which has solved such a problem, is to provide a check valve in the middle of a blow air passage provided inside a bit or an accessory part integrated with the bit. It is in the feature drilling bit.

[0007]

According to the present invention, while the drill bit is in use, the compressed air passes through the air passage provided inside the bit and the portion attached to the bit, passes through the check valve, and comes out from the air jet port at the tip thereof. Blow out. When the supply of compressed air is stopped, underground soil, muddy water, chips, rock powder, etc. will flow in from this air ejection port, but the check valve will check in the air passage of the drill bit or the part attached to it. Since the valve is provided, the entry is stopped at this bit portion, and the sediment is prevented from flowing into the rotary impact mechanism.

Even if the earth and sand are clogged inside the excavating bit or the part attached to the excavating bit, the air passage in the inside has a relatively large passage area, so that the clogging can be eliminated by sending the compressed air into the air passage. Often. Alternatively, it can be easily eliminated by inserting a scraping tool from the air ejection port and scraping out the clogged soil, pebbles, and the like. If the clogging still cannot be solved, the clogging / failure of the check valve can be easily resolved by removing the drill bit from the rotary impact device and performing repair work. Furthermore, if the excavation bit is still difficult to repair, exchanging the excavation bit itself allows the excavation operation to continue without interruption.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment: See FIG. 1) The excavating bit 1 of the embodiment shown in FIG. 1 includes a check valve 4 and an air passage 3 of a bit body 2.
It is provided at the top of. The structure is such that the round-headed valve body 5 is slidably fitted and inserted into a cylinder body 6 mounted in the air passage 3.
This is an example in which a spring 8 that urges the valve toward the valve seat 7 provided in the air passage 3 is provided in the cylindrical body 6.

In the figure, 9 is a cylindrical body mounting portion integrally provided at the base end of the cylindrical body 6, 10 is a valve seat 7 provided inside, and a cylindrical body mounting portion 9 is provided.
Is an outer cylinder that fixes the inner wall of the bit body 2 to form the inner wall of the air passage 3, and 11 is a carbide tip attached to the tip of the bit body 2,
Reference numeral 12 is a spline for attaching the excavation bit 1 to the rotary impacting device, and 13 is an air ejection port of the air passage 3 opened at the tip of the bit body 2.

In this embodiment, when compressed air is sent to the air passage 3, the circular head portion of the valve body 5 of the check valve 4 is pushed down by air pressure so that the air enters the air passage 3 of the bit body 2 and It blows out from the air outlet 13 at the tip. When the supply of compressed air is stopped, the urging force of the spring 8 causes the valve element 5 of the check valve 4 to
The circular head is pressed against the valve seat 7 to prevent dirt, muddy water, chips, etc. from flowing into the rotary impact device. Since the hole diameter of the air passage 3 in the excavation bit 1 is large and the number of bends is small, clogging is less likely to occur. Further, even if clogged, it can be considerably eliminated by sending compressed air to the air passage 3. If it still does not solve, it can be easily solved by inserting a scraping tool from the air ejection port 13. If the clogging cannot be eliminated, the spline 12 may be disengaged and the drill bit 1 itself may be removed from the rotary impact device for repair / replacement. In either case, the clogging can be cleared quickly and easily.

The check valve 4 of the present invention is not limited to the position and structure of the above embodiment. Further, the drill bit of the present invention can be used not only in a rotary impacting device but also in a rotary drilling and drilling device without impact. Figures 2, 3, 4, 5, 6, 7
Shows examples of various check valve positions and structures.

In the example shown in FIG. 2, the position of the check valve 4 is the same as that of the embodiment shown in FIG. 1, but the structure of the check valve 4 is such that a spherical plate-shaped valve body 5 is directly seated by a spring 8 to a valve seat. This is an example in which it is pressed against 7.

In the example shown in FIG. 3, the check valve 4 is provided at the same position as in the above-mentioned embodiment of FIG. 1, but the valve body 5 is flat and pressed against the valve seat 7 by a return spring (not shown). It is an example.

The example shown in FIG. 4 is an example in which the position of the check valve 4 is the same as that of the embodiment of FIG. 1, but a fine net which allows only air and water to permeate is used as the check valve 4.

The example shown in FIG. 5 is an example in which two flat plate-shaped valve bodies 5 pivotally mounted at the center of the air passage 3 are biased to the valve seat 7 by a return spring (not shown).

The example shown in FIG. 6 is a spherical plate-shaped valve body 5 of FIG.
Is an example of a spherical valve body 5.

In the example shown in FIG. 7, a check valve 4 is provided in the middle of a hood valve 14 which integrally extends in a pipe shape upward from the air passage 3 of the bit body 2. The check valve 4 is an embodiment having the same structure as the check valve 4 shown in FIG. In addition, in FIG.
Reference numeral 15 is a mounting cylinder for the excavation bit 1, 16 is a body of the rotary impact device, 17 is a piston for impacting the excavation bit 1, and 18 is an air passage inside the piston.

[0020]

As described above, according to the excavating bit of the present invention, since the check valve is provided in the internal air passage of the inside of the bit or the attached portion integrated with the bit, the earth and sand and the cutting chips.・
Rock powder, muddy water, clay, etc. are prevented from entering the rotary impact device, so that the rotary impact device is not damaged, deteriorated in performance, or inoperable due to earth and sand. Also, blockages in the drill bit can be easily cleared by blowing compressed air or using a scraping tool. Even if the clogging is not cleared yet, excavation work can be continued without much interruption by exchanging the excavation bit itself, and work efficiency is good.
Further, since it is possible to prevent the rotary impact device from causing a failure, the running cost of the excavating machine can be reduced and the durability can be improved.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing the structure of another check valve of the present invention.

FIG. 3 is a cross-sectional view showing the structure of another check valve of the present invention.

FIG. 4 is a cross-sectional view showing the structure of another check valve of the present invention.

FIG. 5 is a cross-sectional view showing the structure of another check valve of the present invention.

FIG. 6 is a sectional view showing the structure of another check valve of the present invention.

FIG. 7 is a vertical sectional view showing another embodiment of the present invention.

[Explanation of symbols]

 1 Drill Bit 2 Bit Main Body 3 Air Passage 4 Check Valve 5 Valve Body 6 Cylindrical Body 7 Valve Seat 8 Spring 9 Cylindrical Body Attachment Part 10 Outer Cylinder 11 Carbide Tip 12 Spline 13 Air Jet Port 14 Hood Valve 15 Mounting Cylinder 16 Body 17 Piston 18 Air passage

Claims (1)

[Claims] 1. A drill bit comprising a check valve in the middle of a blow air passage provided inside the bit or inside an accessory portion integrated with the bit.