JPS63150102A - Upward enlarged hole section boring device - Google Patents

Abstract

PURPOSE:To bore an upward enlarged hole section by inserting a rotational vibration type boring device body with a shank into the straight hole bored in a concrete body beforehand and performing boring with a stop sleeve lower end abutted to a concrete surface. CONSTITUTION:A shank 2 is attached to a rotational vibration type boring device and the lower end side of the device body 3 is inserted into the straight hole A formed in a concrete body beforehand. And the boring device is driven with the lower end face of a stop sleeve 12 abutted to a concrete surface B and kept to a fixed position, and vertically moved rotating a cylindrical body 1. The end section of a cutter body 9 is rotated being put out from the inside of the container hole 7 of the lower end of the body 3 and into the side of the cylindrical body 1 in this state. Since thus an upward enlarged hole section C is formed on the hole wall in the depth of the straight hole A, the drawing strength of anchor bolts against solidified concrete can be substantially improved.

Description

Detailed Description of the Invention (Industrial Application Field) This invention involves cutting an enlarged diameter hole portion in a pre-drilled hole wall at a suitable location, the diameter of which is larger than the drill diameter and whose diameter is directed upward. The present invention relates to a cutting device for cutting.

(Prior Art) In order to increase the pull-out strength of anchor bolts when planting them in solidified concrete, the present invention is used, for example, as a device for cutting enlarged diameter holes at appropriate locations in straight drill holes. The applicant has filed an application and it has already been published (Japanese Unexamined Patent Application Publication No. 60-1
91706), the cutting blade is moved along the overhanging jaw that gradually expands downward and laterally, and the main body of the device is rotated while protruding outward from the overhanging jaw to open the enlarged diameter hole. There are structures that need to be removed.

(Problems to be Solved by the Invention) According to the above-mentioned conventional cutting device, it is possible to cut an enlarged diameter hole where the pull-out strength of the anchor bolt is increased compared to a straight hole. Since the diameter of the anchor bolt is gradually expanded downward (in the opposite direction to the direction in which the bolt is pulled out), the anchor bolt is connected to the expanded diameter hole wall, but since it is not engaged, the bolt is completely expanded. There was nothing that could prevent the withdrawal.

This invention has been made in view of the above-mentioned points, and it is possible to cut an enlarged diameter hole whose diameter is gradually enlarged upward, and it is possible to engage the anchor bolt with the engagement step at the upper end of the enlarged diameter hole, thereby increasing the bolt's pull-out strength. The purpose of this invention is to provide an apparatus for cutting an enlarged diameter hole, which can significantly increase the number of holes.

(Means for Solving the Problems) The gist of the present invention for achieving the above-mentioned object is to provide a cylindrical body having a shank at the upper end and an open lower end, in which the upper part of the main body is rotated integrally and at a constant speed. A downward biasing spring is interposed between the cylindrical body and the main body, and a cutting blade is formed in the accommodation hole opened at the tip of the main body so that it can extend toward the side of the main body. A spring is attached to the blade that urges the blade into the accommodation hole, and an operating rod that causes the blade to protrude to the side of the main body against the spring is attached to the axis of the main body. The operating rod is loosely inserted into the drilled shaft hole so as to be able to move up and down within a certain range, and the upper end of the operating rod is connected via a pin to a stop sleeve that is loosely inserted on the outer periphery of the main body under the cylindrical body. A J-hole communicating with the longitudinal groove formed in the surface is bored, a number of spheres are connected and inserted into the J-hole and the longitudinal groove, and a part of the sphere is fitted into the J-hole at the lower end of the cylindrical body to form an upper end. This is because a pushing member that can come into contact with the spherical body is provided to protrude downward.

(Function) According to the cutting device of the present invention, the shank is connected to a rotary vibration type or rotary hammer type drilling device, the main body is inserted into a straight hole previously drilled in concrete, and the cutting device is stopped on the concrete surface. By performing drilling work with the lower end of the sleeve in contact, the main body with the blade attached rotates while moving up and down, and during this up and down movement, the blade comes into contact with the operating rod that is held in a fixed position. The cutting edge portion at the tip of the blade protrudes to the side of the main body, and an enlarged diameter hole portion whose diameter is gradually enlarged upward is cut.

(Example) Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is a central vertical cross-sectional view of the cutting device of the present invention at the start of work, FIG. 2 is a central vertical cross-sectional view of the same with the cylindrical body pressed down at the end of work, and FIG. FIG. 3 is a perspective view of each component of the device in an exploded state.

In these figures, 1 is a cylindrical body with a shank 2 at the upper end and an open lower end, 3 is a device main body whose upper part is fitted into the cylindrical body 1 so as to be able to move up and down, and the upper end of the main body 3 has a cylindrical body with a shank 2 at its upper end. A vertically elongated insertion hole 4 is bored, and the main body 3 is rotated together with the cylindrical body 1 and can be vertically moved within a certain range via a pin 5 that is loosely inserted through the insertion hole 4 so as to be vertically movable. combined. Further, a spring 6 is interposed between the cylindrical body 1 and the main body 3, and the main body 3 is biased downward.

A blade accommodating hole 7 is formed in the lower end of the main body 3 and passes through it laterally. A shaft hole 8 is bored in the shaft core portion of the main body 3 and communicates with the accommodation hole 7 from the middle portion thereof.

Reference numeral 9 designates a pair of plate-shaped blades having a semicircular base and an isosceles triangular tip. The tip portions of the blade bodies 9 are configured to open in the direction of separation and protrude from the upper end portions of the housing holes 7 to the outside of the main body 3, respectively. Reference numeral 11 denotes a spring interposed between each of the blades 9, which urges the tip of each blade 9 into the accommodation hole 7 in the direction in which the tip of each blade 9 closes.

Further, a cutting edge 9a is provided on the outer edge of the tip portion of the blade body 9.

Reference numeral 12 denotes a stop sleeve fitted onto the outer periphery of the main body 3 below the cylindrical body 1 so as to be able to move up and down; 13 is an operating rod fitted into the shaft hole 8 of the main body 3 so as to be able to move up and down; and 14 is the upper end of the shaft hole 8. The upper end of the operating rod 13 is connected to the upper end of the operating rod 13 by a pin 15 inserted through the insertion hole 14 and freely movable downward. is integrally connected to the lower end of the stop sleeve 12.

Reference numeral 16 denotes a plurality of push members protruding downward from the lower end of the cylindrical body 1 at equal intervals in the circumferential direction. 17 are drilled.

A longitudinal groove 18 is formed on the outer periphery of the main body 3 corresponding to the inner opening of each J hole 17, and a large number of spheres 19 are fitted into each Y hole 7 and the longitudinal groove 18 in a connected manner. Further, the lower part of the pushing member 16 is fitted into the J hole 7 and comes into contact with the sphere 19 at the uppermost end. Therefore, by pushing down the cylindrical body 1 toward the sleeve 12 while holding the stop sleeve 12 in place, the lower end of the pushing member 16 is deeply inserted into the J hole 7, and the sphere 19 is inserted into the longitudinal groove of the main body 3. 18 side, and the main body 3 is pushed upward against the spring 6. At this time, since the operating rod 3 is held in place together with the sleeve 12, the blade 9 of the main body 3 that is in contact with the lower end of the operating rod 13 is moved by the spring 1.
1 and is pushed open by the operating rod 13, and the tip of the blade body 9 protrudes from the accommodation hole 7 to the side of the main body 3. On the other hand, by removing the downward force of the cylindrical body 1, the cylindrical body 1 is pushed upward by the biasing force of the spring 6, and the main body 3 is lowered, so that the pivot pin 10 of the blade body 9 is moved from the lower end of the operating rod 13. As it moves away, the tip end of the blade body 9 closes inward by the biasing force of the spring II and returns into the accommodation hole 7.

Next, the manner of use of the above embodiment will be explained. As shown in Figure 1, attach the shank 2 to a rotary vibration type drilling device (not shown), insert the tip side of the main body 3 into a straight hole A previously drilled in the concrete, and insert the lower surface of the tube sleeve 12 into the concrete. The punching device is driven while the cylinder body 1 is held in a fixed position in contact with the surface B, and the cylinder body 1 is rotated and moved downward by -F. In this state, the tip of the blade 9 rotates from inside the accommodation hole 7 at the lower end of the main body 3 while moving in and out to the side of the main body 1, so that the hole wall at the back of the straight hole A has an upwardly expanded diameter. The diameter hole is gradually cut away. In this way, the enlarged diameter hole C shown in FIG. 2 is finally cut. In addition, in order to simplify the explanation, the shank 2 of the device
The side of the blade 9 was taken as the upper end, and the side of the blade 9 was taken as the lower end, but the drilling work of the enlarged diameter hole by this cutting device is performed not only for downward straight holes but also for upward or sideways straight holes. be done.

(Effects) As explained above, since the enlarged diameter hole cutting device of the present invention has the above-described configuration, it has the following effects.

That is, since the enlarged diameter hole cut by the cutting device of the present invention expands upward, in other words, in the direction in which the anchor bolt is pulled out, there is a kind of gap between the upper end of the enlarged diameter hole and the straight hole wall. Since an engagement stage is formed, when implanting an anchor bolt into solidified concrete, etc., by using an anchor bolt equipped with an engagement part with the engagement stage, it is possible to avoid the conventional method. Compared to installing an anchor bolt in a hole whose diameter expands downward, the pull-out strength is greatly increased, and it is reliable and strong, especially when the properties of the material to be drilled are weaker than concrete. Anchor bolts can be planted in.

[Brief explanation of the drawing]

FIG. 1 is a central vertical cross-sectional view of the cutting device according to the embodiment of the present invention at the start of work, FIG. 2 is a central vertical cross-sectional view of the same with the cylindrical body pushed down at the end of work, and FIG. FIG. 3 is a perspective view of each component of the cutting device of the invention in an exploded state. ■... Cylindrical body, 2... Shank, 3... Device body, 4゜14... Insertion hole, 5, 10.15... Pin,
6.11...Spring, 7...Accommodation hole, 8...Shaft hole,
9...Blade body, 9a...Cutting blade, 12...S1-tube sleeve, 13...Operation rod, 1G...Pushing member, 1
7... J hole, 18... Vertical groove, 19... Sphere.

Claims (1)

[Claims] The upper part of the main body is inserted into a cylindrical body having a shank at the upper end and an open lower end so that it can rotate together and move up and down within a certain range, and a downward biasing spring for the main body is interposed between the cylindrical body and the main body. A blade body with a cutting edge that can be extended toward the side of the main body is installed in a housing hole formed at the tip, and a spring is attached to the blade body to bias the blade body into the housing hole. An operating rod that protrudes to the side of the main body against the spring is loosely inserted into a shaft hole drilled in the shaft core of the main body so that it can move up and down within a certain range, and is loosely inserted on the outer periphery of the main body under the cylindrical body. The upper end of the operating rod is connected via a pin to the stop sleeve, and a J hole is bored through which the upper end of the stop sleeve communicates with a longitudinal groove formed on the outer circumferential surface of the main body.
A number of spheres are connected and fitted into the J hole and the longitudinal groove, and a push member is provided at the lower end of the cylindrical body to protrude downward and is partially fitted into the J hole and can come into contact with the upper sphere. An upward diameter expansion hole drilling device characterized by: