JPH0583096U - Drilling blade for foundation pile - Google Patents

Abstract

(57) [Summary] [Purpose] An excavating blade used in a rotary foundation construction machine that excavates underground to construct a foundation pile, reduces abnormal force applied to the blade, and replaces the blade. The present invention provides an excavating blade that is easy and has no fear of the carbide tip falling off. In a large number of excavating blades that are detachably attached to a holder member 1 at the tip of a rotating casing, the attaching / detaching direction of the blade portion 2 is made to coincide with the resultant direction of the rotating force and the pushing force of the casing during excavation, and To insert the portion 2, the holder member 1 is sandwiched between the forked portions at the rear portion of the blade portion, and both outer side surfaces of the forked portion and the holder member are fitted and fixed in a spigot manner.
Further, an integrally formed protrusion 5 extending from the holder member is provided on the side opposite to the rotating direction of the blade portion protruding from the casing body.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an excavating blade used in a rotary foundation construction machine for excavating underground to construct a foundation pile.

[0002]

[Prior Art]

 Conventionally, in this type of machine, there are the following two types of blades attached to the casing.

(1) Integral Tooth As shown in FIG. 5, a steel material 11 having a cemented carbide tip brazed on its tip is welded and attached to a casing.

(2) Two-piece tooth As shown in FIG. 6, the blade portion has a two-piece structure of a point portion 13 and a holder portion 14, the holder portion 14 is welded to the casing, and the point portion 13 is locked to the holder portion 14. The member 15 is fixed. There are various conceivable ways of connecting the bolt 15, the holder 14, and the point 16 of the fitting portion of the two-body type tool as shown in FIGS. In addition, 17 in (c) of FIG. 7 is a wedge.

[0005]

[Problems to be solved by the device]

 The above-mentioned integrated tooth is very difficult to replace the blade portion with a new one when the blade becomes uncut.

Since the two-piece tool has a two-piece structure, the point portion must be naturally large in order to withstand the strong rotational force of the casing. If the width of this point is large, if the casing diameter is small, it will protrude from the casing, which will cause resistance when the casing rotates, which is unsatisfactory. If the cutting edge cannot withstand the rotational force, another piece may be welded to the back side of the blade to support the rotational force. Most of the two-body type teeth are made by machining, and the fitting part has no pulling control because of the high processing cost. Also, since the play at the point of use is unclear, it is made with dimensional accuracy without play. For this reason, after use, dirt or the like may enter the fitting part and become stuck when the point is replaced. In the case of the bolt-fastening method, the bolt head may be worn after use and the bolt may not be removed when the point is replaced. In addition, the bolt may loosen during use and the point may not be fixed, resulting in damage. For example, as shown in Fig. 7 (c), the structure that surrounds a part of the outer circumference of the holder may not be enough for welding the holder to the casing, so the holder may be removed during use. Most of the cemented carbide tips are brazed on the two surfaces that receive the force in the casing rotation direction and the pushing direction, so if frictional heat is generated during use and a lateral load acts, the cemented carbide tip will be harder than the brazed portion. The tip may slip sideways and fall off. If the tip falls off during use and falls into the excavated rock ditch, the tip interferes and no further excavation is possible.

The present invention is intended to solve various problems in the two-body type tooth.

[0008]

[Means for Solving the Problems]

 The present invention, in a large number of cutting blades that are detachably attached to the holder member at the tip of the rotating caging, makes the attaching / detaching direction of the blade portion coincide with the resultant direction of the rotating force and the pushing force of the casing during excavation, and To insert the blade part, insert the holder between the two forked parts at the rear part of the blade part, and fix both outer surfaces of the two forked parts and the holder by fitting in the spigot type, and the blade part protruding from the casing body. It is an excavating blade for foundation piles, which is provided with an integrally formed protrusion extending from the holder on the opposite side of the rotation direction.

In such a device of the present invention, when the point portion is attached to the holder and excavated, the rotating force and the pushing force of the casing act on the casing from the machine body, and the tip of this casing acts like a saw blade. Rocks are excavated and perforated by the attached blades. Actually, excavation is performed by the resultant force of this rotational force and pushing force. In the present invention, by tilting the insertion direction of the point fitting portion toward this resultant direction, the point portion is pushed into the holder side, which is different from the conventional fitting shape that inserts vertically. It works honestly, and in a nutshell, it works fine when excavating without a lock member. Actually, at the end of excavation, the casing body is pulled out and the process moves to the excavation of the next foundation hole, so it is necessary to maintain points and the locking member is required.

The component force at the time of excavation is transmitted from the point part to each place of the holder part, and the spigot type fitting of the forked part extending from the point part and the holder serves to support the lateral load acting on the point part. . Also, the integrally formed protrusion extending from the holder backs up the force coming from the rotation direction. The cemented carbide tip is brazed on three sides, which are the direction of rotation, the direction of pushing, and the lateral load.

[0011]

【Example】

 An embodiment will be described with reference to the drawings.

FIG. 1 is an exploded perspective view of the embodiment, and FIG. 2 is a sectional view taken along the line AA. In the figure, 1 is a holder member, 2 is a blade portion, and 3 is a locking member. A dovetail groove 4 is formed on both sides of the holder member 1 in the direction in which the rotational force and the pushing force of the casing to which the holder member 1 is to be attached are formed. A protrusion 5 is formed on the side. The blade portion 2 is divided into a forked point portion 6 at the upper end so as to be fitted in the dovetail groove 4, and a carbide tip 7 is attached to the blade edge. If the dovetail groove 4 and the blade portion 2 are slightly tapered, they can be easily attached and detached. The cutting edge has an outer blade protruding outside the casing, an inner blade protruding inside, and a middle blade intermediate between the blades, and the blades are attached to the casing in an appropriate saw-tooth arrangement. For attachment, the holder member 1 is welded to the lower end of the casing at regular intervals, the point portion 6 of the blade portion 2 is inserted into the dovetail groove 4, and the lock member 3 is inserted through the lock holes 8 and 8'and fixed. The lock member 3 is preferably one that can be inserted and removed from the inside or outside of the casing. The cemented carbide tip 7 is fixed by brazing the surface 7'for receiving the rotation direction, the surface 7 "for receiving the pushing direction and the surface 7 '" for receiving the lateral load.

As shown in FIGS. 1 and 2, the resultant force applied to the excavating blades of the present invention thus combined is transmitted from the point portion 6 to the portions a, b, c and d of the holder member. Be done. Further, the bifurcated portion of the point portion 6 plays a role of supporting a lateral load acting on the point portion 6 by means of the c, d, e and f inlay portions of the holder member 1. On the other hand, the force acting on the cemented carbide tip 7 is supported by the mounting pedestal-shaped surfaces 7 ', 7 ", 7'" at the points. In particular, the lateral load plays a role of being supported by the surface 7 ′ ″ receiving the same load, that is, one side surface of the blade base.

[0014]

[Effect of the device]

 According to the present invention, the point portion of the blade portion receives the component force generated by the rotational force and the pushing force at the time of excavating the casing, and the point portion is in the same direction as the resultant force and the fitting between the holder member and the blade portion. Depending on the structure, it works to be fixed to the holder, and the lock part for holding the point part during excavation may not be needed, but it is a two-body type, but it exhibits stability close to an integrated tooth. The holder has a structure that is compatible with the outer, middle and inner blades of the blade, and the combination of the arrangement of the blades (outer blade, middle blade, inner blade) can be changed during use in the field. Should a need arise, it can be easily replaced on site without using a welding machine, gas, etc. By forming the pedestal for mounting the cemented carbide tip that supports the lateral load in the shape of the present invention, the tip does not fall into the groove of the rock as in the conventional case, and it does not interfere with the excavation and make it impossible to excavate. The two-piece tooth of the present invention is easy to handle at the site of use, excavation geology changes in the middle, lowers excavation efficiency, and even if it is necessary to change the arrangement of blades, tip materials, etc., it is easy on the spot. Can be changed to It is also very effective as it helps improve work efficiency without worrying about the tip slipping off and causing it to fall off.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is an explanatory diagram of a casing.

FIG. 4 is an explanatory diagram of a blade portion of a casing.

FIG. 5 is a perspective view of an example of a conventional integrated tooth.

FIG. 6 is an exploded perspective view of an example of a conventional two-body tooth.

FIG. 7 is a cross-sectional view showing a conventional joint formation of a bolt, a holder, and a point.

[Explanation of symbols]

 1 Holder member 2 Blade part 3 Lock member 4 Dovetail groove 5 Projection part 6 Point part 7 Carbide tip 7'Surface for receiving rotation direction 7 "Surface for receiving pushing direction 7" 'Surface for receiving lateral load 8, 8' Lock hole

Claims (4)

[Scope of utility model registration request] 1. A large number of excavating blades detachably attached to a holder member at the tip of the rotating caging, the attaching and detaching directions of the blades are aligned with the resultant direction of the rotating force and pushing force of the casing during excavation, and When inserting the blade part, the holder is sandwiched by the forked part at the rear part of the blade part, and both outer side surfaces of the forked part and the holder are fitted and fixed in a spigot type, and the blade part protruding from the casing body is fixed. An excavating blade for a foundation pile, characterized in that an integrally formed protrusion extending from a holder is provided on the side opposite to the rotating direction. 2. The foundation pile excavating blade according to claim 1, wherein the blade tip is provided with an inner blade, a middle blade, and an outer blade, each of which is interchangeable. 3. The excavating blade for a foundation pile according to claim 1, wherein the blade portion and the holder are fixed by a lock member that is detachable from both inside and outside of the casing. 4. The excavating blade for a foundation pile according to claim 1, wherein the cemented carbide tip of the blade tip portion of the blade portion is attached leaving one side surface portion of the blade base.