JP4654270B2 - Bit holder and cutting blade and auger head - Google Patents

Description

  The present invention relates to an excavation claw and an auger head for excavating the ground, and more particularly, to an auger head structure, an earth auger head bit holder, and a cutting blade mounting structure.

  A structure in which the bit of the earth auger can be replaced is described in, for example, Patent Document 1 below. As shown in FIG. 9, this detachable earth auger bit includes a bit body 51, a bit holder 52, and a connecting member 53. The bit body 51 includes a cutting head 512 provided with a cutting blade 511 and a fixed rod 513 connected to the cutting head 512. The fixing rod 513 has a pair of cylindrical portions 513b and an intermediate constricted portion 513a whose cross-sectional shape perpendicular to the axial direction is arranged vertically, and one side surface is in a semi-missed state. A recess 514 is formed. The bit holder 52 is provided with a receiving hole 521 into which the fixing rod is inserted, and a mounting hole 522 that intersects the receiving hole is formed on the upper and lower surfaces. The connecting member 53 includes a bolt 531 and a nut 532. The bit is attached to the screw by inserting the fixing rod 513 of the bit body 51 into the receiving hole 521 of the bit holder 52 fixed by welding to the screw of the earth auger and inserting the connecting member 53 into the mounting hole 522.

This detachable earth auger bit uses a sword blade bit body having a specially shaped fixing bar and a bit holder for receiving it, so that a normal conical bit (round blade bit) can be rotated to the bit holder. It cannot be installed as possible. In order to attach such a round blade bit, it is necessary to replace the bit holder itself or replace the auger head to which the bit holder is fixed.
JP 2002-339680 A

  The present invention relates to a round blade bit (rotatable cutting blade) having a conventional shape, which is mounted rotatably about a longitudinal axis of the bit, and a fixed sword blade bit (rotation is restricted). It is an object of the present invention to provide a bit holder capable of selecting and attaching a plurality of types of bits of the cutting blade), a structure of a sword blade bit attached to the holder, and an earth auger head provided with the bit holder.

  In order to solve the above-mentioned problems, the present invention provides a sword blade that is a cutting blade whose rotation is restricted while a circular blade bit that is a rotatable cutting blade is rotatably attached to the structure of the bit holder. The bit can be attached so as not to rotate. That is, the bit holder of the present invention includes a receiving portion that rotatably receives the round blade bit and a receiving portion that prevents rotation of the blade tip blade bit, and the receiving portion that prevents rotation is rotatable. It was set as the structure which does not prevent rotation of the round blade bit in a part.

  By providing the above configuration, the bit holder of the present invention can be attached to the bit holder so that the round blade bit and the sword blade bit can be exchanged, and the bit is selected according to the change in the state of the formation to the auger head. Since it can be attached and used, it is not necessary to replace the auger head in accordance with changes in the state of the formation, and it is not necessary to provide a plurality of auger heads.

[Embodiment 1] The structure of a bit holder and a sword blade bit according to the present invention will be described with reference to FIGS. FIG. 1 is a top view of a state in which the upper stage has a sword blade bit attached to a bit holder, and the lower stage is a front view thereof. FIG. 2 is a diagram for explaining the structure of the bit holder, with the upper stage being a top view, the lower stage right being a front view thereof, and the lower stage left being a left side view thereof. FIG. 3 is a view for explaining the structure of the sword blade bit, wherein the upper stage is a top view, the lower stage left is a front view thereof, and the lower stage right is a right side view thereof.

  As shown in FIG. 2, the bit holder 1 is configured as a rectangular parallelepiped, and includes a fixed rod receiving hole 11, a mounting hole 12, a blade tip blade receiving portion 13, and a round blade bit receiving portion 14. .

  The fixing rod receiving hole 11 is a hole for receiving the fixing rod of the bit, and has a circular cross-sectional shape in a plane orthogonal to the axial direction of the fixing rod so that the inserted fixing rod can rotate inside. The bottom portion 111 of the fixing rod receiving hole 11 can also support the rear end portion of the fixing rod.

  The mounting hole 12 is a hole that passes through a part of the side of the circular cross section of the fixing rod receiving hole 11 and penetrates from the upper surface to the lower surface of the bit holder 1, and the mounting rod 49 fits into the pin receiving groove 42 of the inserted fixing rod. In addition, it has a function of restricting the movement of the bit in the front-rear direction and holding the bit in a rotatable manner.

  The sword blade bit receiving part 13 is constituted by a vertically long groove provided on the end face of the bit holder 1, and has a sword blade bit receiving surface 131, a guide wall 132, and a bottom surface 133.

  The round blade bit receiving portion 14 has a circular hole having a size to receive the round blade bit 4b provided on the end face of the bit holder 1, and the round blade bit receiving portion peripheral wall surface 141 and the round blade bit receiving portion. And a bottom surface 142. The round blade bit receiving portion bottom surface 142 is a surface that receives the end surface 442 of the round blade bit. The round blade bit receiving portion peripheral wall surface 141 is a wall surface that constitutes a hole into which the round blade bit is inserted, and is provided in such a shape that a part of the regulation wall 132 of the sword blade bit receiving portion 13 is extended outward. The blade bit is rotatably supported.

  As shown in FIGS. 1 and 3, the sword blade bit 4 a includes a fixed rod 41, a pin receiving groove 42, a locking portion 43, a ridge 46, and a sword blade 48. The fixing bar 41 is provided at the rear part of the blade tip bit, and a locking part 43 and an annular pin receiving groove 42 are provided at the rear end part thereof.

  The pin receiving groove 42 is restricted from moving in the front-rear direction by inserting the mounting rod 49 into the mounting hole 12 with the fixing rod 41 inserted into the fixing rod receiving hole 11 of the bit holder 1.

  The locking portion 43 prevents the cutting blade bit from coming off together with the mounting rod 49.

  The ridge 46 is provided so as to be fitted to the sword blade bit receiving portion 13 of the bit holder 1, and when the sword blade bit 4a is attached to the bit holder 1, the peripheral wall 462 of the projection 46 of the sword blade bit 4a is In contact with the regulating wall 132 of the sword blade bit receiving part 13, the rotation on the bit longitudinal axis is regulated.

  The sword blade 48 has a sword blade tip 483 fixed to the tip thereof by welding or the like, and a hardfacing portion 482 is provided behind the sword blade 48 so as to cover the sword blade 48. The rear part of the sword blade 48 is widened and a sword blade locking surface 481 is provided.

  As shown in FIG. 1, after inserting the fixing rod 41 of the blade tip blade bit 4 a into the fixing rod receiving hole 11 of the bit holder 1 and then inserting the mounting rod 49 into the mounting hole 12, the blade tip blade bit 4 a Is restricted, and the rotation is restricted by the restriction wall 132 of the bit receiving portion 13. As a result, the blade edge locking surface 481 of the blade edge blade bit 4 a is received by the blade edge blade receiving surface 131 of the bit holder 1.

  In this way, the sword blade bit 4a attached to the bit holder 1 is attached while its movement in the front-rear direction is restricted, and the rotation around the longitudinal axis of the sword blade bit 4a is also restricted.

  In the above description, the sword blade bit 4 a has a structure in which the sword blade locking surface 481 is received by the sword blade bit receiving surface 131 of the bit holder 1, but the convex bottom surface 461 of the sword blade bit 4 a is It is good also as a structure received by the sword blade edge | bit bit receiving part bottom face 133.

  A state in which the round blade bit 4b is attached to the bit holder 1 of the invention will be described with reference to FIGS. The round blade bit 4b includes a fixed rod 41, a pin receiving groove 42, a locking portion 43, a convex portion 44 having a circular cross section having a convex portion bottom surface 441 and a convex portion peripheral wall surface 442, and a circular blade tip at the tip. It consists of a round blade 45 provided with a tip 451 to which 452 is attached.

  By inserting the fixing rod 41 of the round blade bit 4b into the fixing rod receiving hole 11 of the bit holder 1 and inserting the mounting rod 49 into the mounting hole 12, the forward and backward movement of the round blade bit 4b is restricted. It is attached. The convex portion 44 of the round blade bit 4b is inserted into the round blade bit receiving portion 14, the bottom surface 441 of the convex portion is supported by the bottom surface 142 of the round blade bit receiving portion, and can be rotated around the longitudinal axis of the bit. Supported by

[Embodiment 2] A second embodiment of the present invention will be described with reference to FIGS. This embodiment is an example in which the rotation restricting portion for restricting the rotation of the blade tip blade bit in the first embodiment is provided outside the cutting blade rotation receiving portion, and the blade edge blade bit is the cutting blade rotation receiving portion. It was comprised so that it might be supported by. FIG. 6 is a front view and a right side view showing the structure of the blade tip bit 4c in the present embodiment, and FIG. 7 is a front view, a left side view and a side view showing the structure of the bit holder 1b of this embodiment. It is sectional drawing in the II line.

  The blade tip bit 4c according to the second embodiment includes a fixed rod 41, a pin receiving groove 42, a locking portion 43, a convex portion 44, and a blade tip blade 48. The fixing bar 41 is provided at the rear part of the blade tip bit, and a locking part 43 and an annular pin receiving groove 42 are provided at the rear end part thereof. The pin receiving groove 42 is restricted from moving in the front-rear direction by inserting the mounting rod 49 into the mounting hole 12 in a state where the fixing rod 41 is inserted into the fixing rod receiving hole 11 of the bit holder 1. The sword blade 48 has a sword tip tip 483 fixed at the tip thereof, and a hardened portion 482 is provided behind the sword tip blade 48 so as to cover the sword tip blade 48. Is provided.

  In the present embodiment, a rotation preventing protrusion 463 that protrudes outward is provided on the peripheral wall surface 442 of the protrusion 44. In this example, the rotation-preventing protrusion 463 is provided with a bottom 4631 closer to the tip than the convex bottom 441.

  The bit holder 1 b has a fixing rod receiving hole 11, a mounting hole 12, and a round blade bit receiving portion 14. Furthermore, a plurality of blade tip bit receiving portions 134 are provided on the peripheral wall 141 of the round blade bit receiving portion of the bit holder 1b toward the outside of the peripheral wall. The sword blade bit receiving part 134 is provided such that the sword blade bit receiving part bottom surface 1341 is closer to the sword tip side than the round blade bit receiving part bottom surface 142.

  When the blade tip bit 4c is attached to the bit holder 1b, the fixing rod 41 is inserted into the fixing rod receiving hole 11, and the convex portion 44 is inserted into the round blade bit receiving portion 14 of the bit holder 1b. The convex portion bottom surface 441 is supported by the round blade bit receiving portion bottom surface 142. The rotation preventing protrusion 463 is inserted into the sword blade bit receiving part 134, and the rotation of the side wall 4632 is restricted by the side wall 1342 of the sword blade bit receiving part 134.

  In this way, like the first embodiment, for example, a round blade bit having a rotatable cutting blade and a cutting edge blade bit having a cutting blade whose rotation is restricted by using the same bit holder. Both of them can be selected and attached.

  In this embodiment, the bottom surface 1341 of the sword blade bit receiving part 134 is provided so as to be closer to the sword tip side than the bottom surface 142 of the round blade bit receiving part 14, but the sword blade bit receiving part bottom surface 1341 is a round blade bit. The same surface as the receiving portion bottom surface 142 may be used. In this case, the rotation-preventing protrusion bottom surface 4631 of the sword blade bit 4 c is the same surface as the bottom surface 441 of the convex portion 44.

  The example which attached the bit to the bit holder concerning this invention welded to the auger head using FIG. 8 is demonstrated. The auger head 2 includes a rotating shaft 21, two blades 22 spirally wound around the rotating shaft 21, and a coupling portion 23 provided on the upper portion of the rotating shaft 21. The bit holder 1 according to the present invention and the conventional bit holder 3 are fixed to the tip of the blade 22 by welding, and the bit 4 is attached to each bit holder 1, 3.

  As described above, according to the present invention, it is possible to select and attach both the round blade bit that is rotatably supported by the single bit holder and the blade tip blade bit whose rotation is restricted.

The figure explaining the state which fixed the sword-tip blade bit to the bit holder concerning this invention. The figure explaining the shape of the bit holder concerning this invention. The figure explaining the shape of the sword blade bit concerning this invention. The figure explaining the shape of the round blade bit attached to the bit holder concerning this invention. The figure explaining the state which fixed the round blade bit to the bit holder concerning this invention. The figure explaining the shape of the sword blade bit concerning the 2nd example of the present invention. The figure explaining the shape of the bit holder concerning the 2nd example of the present invention. The figure explaining the form of the auger head which attached the bit holder concerning this invention. The figure explaining the structure of the conventional sword-tip blade bit and bit holder.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1a, 1b: Bit holder 11: Fixed rod receiving hole 111: Fixed rod receiving hole bottom part 12: Mounting hole 13: Blade edge bit receiving part 131: Blade edge bit receiving surface 132: Restriction wall 133: Blade edge bit receiving part bottom face 134 : Blade tip bit receiving portion 1341: Blade tip bit receiving portion bottom surface 1342: Blade tip blade bit receiving portion side wall 14: Round blade bit receiving portion 141: Round blade bit receiving portion peripheral wall surface 142: Round blade bit receiving portion bottom surface 2 : Auger head 3: Conventional bit holder 4: Drilling blade (bit)
4a, 4c: Blade tip blade bit 4b: Round blade bit 41: Fixed rod 42: Pin receiving groove 43: Locking portion 44: Convex portion 441: Convex portion bottom surface 442: Convex portion peripheral wall surface 45: Round blade 451: Tip Part 452: Round blade tip 46: Projection strip 461: Projection strip bottom surface 462: Projection strip guide surface 463: Rotation prevention projection portion 4631: Rotation prevention projection bottom surface 4632: Rotation prevention projection side wall 48: Blade edge 481: Blade edge locking surface 482: Hardened thick part 483: Blade edge tip 49: Mounting rod 51: Bit body 511: Cutting blade 513: Cutting head 513: Fixed rod 513a: Constriction portion 513b: Cylinder portion 514 : Retaining recess 52: bit holder 521: receiving hole 522: mounting hole 53: connecting member 531: bolt 532: nut

Claims (8)

In the bit holder fixed to the auger head of the earth auger,
A fixing rod receiving hole for receiving the fixing rod of the cutting blade and a mounting hole for inserting the mounting rod for attaching the fixing rod;
Provided on the end face with a rotation preventing portion for restricting rotation of the cutting blade and a cutting blade rotation receiving portion for allowing rotation of the cutting blade ,
The bit holder according to claim 1, wherein the cutting blade rotation receiving portion is provided with a bottom surface behind the rotation blocking portion . The bit holder according to claim 1,
The rotation preventing unit, the bit holder, characterized in that it is composed of a groove shape provided on the end face of the bit holder. The bit holder according to claim 2,
A bit holder characterized in that the surfaces of both end portions of the groove of the rotation preventing portion are surfaces that receive cutting blades whose rotation is restricted. The bit holder according to claim 1,
The rotation preventing unit, the bit holder, characterized in that it is composed of a groove shape extending inwardly from the end face of the bit holder. The bit holder according to claim 1 ,
A bit holder, wherein a bottom surface of the cutting blade rotation receiving portion is a receiving surface of a cutting blade that allows rotation . In the cutting blade in which rotation attached to the bit holder according to claim 2 is regulated,
Protruding strips fitted to the rotation preventing portion are provided on the surface facing the bit holder.
A cutting blade whose rotation is restricted . In the cutting blade in which rotation attached to the bit holder according to claim 4 is regulated,
Provided with a ridge that fits into a groove extending inward from the end face of the bit holder
A cutting blade whose rotation is restricted . In the auger head that fixes the bit holder that attaches the cutting blade to the tip,
The bit holder includes a fixing rod receiving hole for receiving a fixing rod of the cutting blade and a mounting hole for inserting a mounting rod for attaching the fixing rod, and a rotation preventing portion for restricting the rotation of the cutting blade on the end surface and the rotation of the cutting blade. A cutting blade rotation receiving portion to allow, and the cutting blade rotation receiving portion is provided with a bottom surface behind the rotation blocking portion.
An auger head characterized by that .

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