JP2015036467A - Excavation tool and swing control pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely perform the expansion and contraction of a hole in spite of being low cost.SOLUTION: An excavation tool includes: a tool body 10 formed in a substantially circular column shape and having a movable blade fitting surface flatly chamfered along an axial direction formed on a tip side outer periphery; a movable blade body of which base end is connected to a movable blade fitting surface to be swingable along the movable blade fitting surface, and of which tip side is movable outward in the radial direction of the tool body 10 by a centrifugal force during rotation of the tool body 10; and a swing control pipe fitting to an outer periphery of the tool body 10 slidably in a center axis direction of the tool body 10. The swing control pipe restricts swing of the movable blade body when it is positioned at a swing restraining position P1, and allows the swing of the movable blade body when it is positioned at a swing allowable position P2.

Description

  The present invention relates to an excavation tool and a swing control pipe for expanding and reducing a hole excavated in the ground or a natural ground in order to install an anchor, a rock bolt, a foundation pile, or the like.

  At excavation sites such as mines and tunnels, anchors and rock bolts are installed in holes excavated in natural ground to reinforce natural ground. Furthermore, in order to reinforce the natural ground more firmly, an enlarged portion with an enlarged inner diameter is formed at the tip and middle of the hole through which the anchor and lock bolt penetrate, and the filling volume of cement and mortar in this portion is increased. An increase is being made.

  As a drilling tool for forming a hole having such an enlarged diameter portion, Patent Document 1 discloses that a bit is projected and retracted in a radial direction by a wedge-shaped member that advances and retreats in the axial direction of the drill bit body. Thus, a configuration that enables expansion and contraction of the hole is disclosed.

  Further, in Patent Document 2, the bit body for excavation having a bit head composed of two blocks is rotated, and the bit head is pressed against the ground around the hole, thereby rotating the two blocks constituting the bit head. The structure which provides resistance and makes two blocks protrude in the outer peripheral side is disclosed.

JP 7-229382 A Japanese Unexamined Patent Publication No. Sho 63-11789

  However, according to the configuration described in Patent Document 1, a wedge-shaped member and a mechanism for advancing and retracting the member are required to make the bit appear and disappear in the radial direction, and the structure is complicated and costly. There is a problem that it takes.

  The excavation bit described in Patent Document 2 is an excavation bit intended to start excavation in a diameter-expanded state at the start of excavation, and to recover the bit after reducing the diameter. Therefore, this drill bit is not assumed to have an enlarged / reduced diameter in the middle of work, and even when trying to shift from the reduced diameter state to the enlarged diameter state in the hole, in this drill bit configuration, the hitting is only in the axial direction of the hole. Therefore, it is impossible to generate a force for pressing the bit head against the inner surface of the hole, and it is impossible to dig the hole wall and expand the diameter. Such a problem is common not only when forming holes for foundation piles built in the ground, but also for holes for anchors and rock bolts.

  Accordingly, an object of the present invention is to provide an excavation tool and a swing control pipe that can reliably expand and contract holes while being inexpensive.

The present invention employs the following means in order to solve the above problems.
That is, the excavation tool of the invention of claim 1 is formed in a substantially columnar shape, and a movable blade mounting surface that is chamfered flat along the axial direction is formed on the outer periphery on the front end side, and for excavation on the front end surface. A tool body having a tip implanted therein, a tip for excavation being implanted at a distal end surface thereof, and a base end coupled to the movable blade attachment surface so as to be swingable along the movable blade attachment surface; A movable blade body whose tip side can move outward in the radial direction of the tool body by centrifugal force when the body rotates, and a cylindrical shape that fits on the outer periphery of the tool body so as to be slidable in the central axis direction of the tool body When the tip cylinder part is formed in the structure and is positioned at the swing restraint position set on the tool body, the tip cylinder part covers the movable blade body, and the tip side of the movable blade body is the tool body To move outward in the radial direction of Permits movement of the distal end side of the movable blade body outward in the radial direction of the tool body when positioned at a swing allowable position retracted by a predetermined distance from the swing restraint position along the central axis of the tool body. And a swing control pipe that is provided.

In the excavation tool, when the tool body is rotationally driven with the swing control pipe positioned at the swing allowable position, the distal end side of the movable blade body is moved outward in the radial direction of the tool body by the centrifugal force at that time. Because of the movement, a hole having a larger diameter can be excavated as compared with the case where the tool body is rotationally driven with the swing control pipe positioned at the swing restraint position.
Therefore, the tool main body is rotationally driven with the swing control pipe positioned at the swing restraint position to excavate a pilot hole whose inner diameter becomes the reference diameter, and then the swing control pipe of the excavating tool extracted from the pilot hole. Is moved to the swing allowable position. Next, the excavation tool with the swing control pipe positioned at the swing allowable position is not rotated and is reinserted into the pilot hole, and the tip of the movable blade on the drilling tool is the position where the diameter of the drill hole is to be expanded. Is reached, the excavation tool is rotated. Then, the distal end side of the movable blade attached to the tool body moves outward in the radial direction of the tool body by the centrifugal force during rotation, so that the diameter to be excavated is widened and expanded to an arbitrary position of the pilot hole An enlarged diameter part can be formed.
That is, in the excavation tool, a hole having an enlarged diameter portion can be formed with a single excavation tool. Moreover, since the movement of the movable blade body outward in the radial direction when forming the enlarged diameter portion is performed by a centrifugal force acting when the tool body is rotated, the movable blade body is moved outward in the radial direction. A special drive mechanism is not required, and the manufacturing cost of the drilling tool can be reduced by simplifying the configuration of the drilling tool. In addition, since the swing control tube is positioned at the swing restraint position, the swing of the movable blade body on the distal end side in the radial direction can be reliably controlled, so that the movable blade body swings carelessly. It is possible to prevent the diameter of the hole excavated by movement.
Therefore, in the excavation tool, the hole can be reliably expanded and contracted at a low cost, and the hole having the enlarged diameter portion can be formed at a low cost.

According to a second aspect of the present invention, in the excavation tool according to the first aspect, the proximal end side cylinder portion of the swing control pipe fitted to the outer periphery of the tool main body has a direction perpendicular to the axis of the tool main body. A first position corresponding to the engagement hole on the swing control pipe located at the swing restraint position on the outer peripheral surface thereof; and A communication passage portion communicating with the engagement hole is provided at two positions, the second position corresponding to the engagement hole on the swing control pipe located at the swing allowable position, and the swing control pipe is provided with the swing passage. The swing control pipe located at the movement restraint position or the swing allowable position has a tool driven by a pin that is driven into the engagement hole so as to straddle the engagement hole and the communication passage portion whose positions are aligned. It is fixed to the main body.
As a result, the swing control pipe can be securely fixed to the swing restraint position or the swing allowable position only with a pin that is a simple structural component, and the swing control pipe is inadvertently positioned during excavation work. It is possible to prevent deviation.

According to a third aspect of the present invention, in the excavation tool according to the first aspect, an inner periphery of the base end side cylindrical portion of the swing control pipe fitted to the outer periphery of the tool main body is provided with the base end side cylindrical portion. A locking groove that goes around the inner periphery is provided, and the tool body has a first position corresponding to the locking groove on the swing control pipe located at the swing restraining position on the outer peripheral surface thereof. And a connecting groove that circulates around the outer periphery of the tool body at two positions, the second position corresponding to the locking groove on the swing control pipe located at the swing allowable position. The swing control pipe located at the swing restraining position or the swing allowable position is formed in an outwardly convex arc shape and protrudes inwardly with a convex arc portion that fits into the locking groove. The concave arc portions that are formed in an arc shape and are fitted in the connecting groove alternately in the circumferential direction, and a thrust load greater than or equal to a predetermined value is applied to the concave arc portion. To act, the arcuate portion so that the recessed circular portion is disengaged from the coupling groove by a ring-shaped spring member is elastically deformed, characterized in that it is fixed to the tool body.
As a result, the swing control pipe can be securely fixed to the swing restraint position or the swing allowable position with only a ring-shaped spring member, which is a simple structural component. It is possible to prevent the misalignment.
Further, in the ring-shaped spring member, when a predetermined thrust load or more is applied to the concave arc portion, the concave arc portion is detached from the connecting groove of the tool body. Therefore, when the swing control tube is moved from the swing restraint position to the swing allowance position, or when it is moved from the swing allowance position to the swing restraint position, a thrust load exceeding a predetermined value is applied to the swing control tube itself. Therefore, it is possible to easily switch the position of the swing control pipe.

According to a fourth aspect of the present invention, in the excavating tool according to the first aspect, the proximal end side cylindrical portion of the swing control pipe fitted to the outer periphery of the tool main body is provided on the inner periphery of the proximal end side cylindrical portion. A locking groove that goes around the inner periphery is provided, and the tool body has a first position corresponding to the locking groove on the swing control pipe located at the swing restraining position on the outer peripheral surface thereof. And a connecting groove that circulates around the outer periphery of the tool body at two positions, the second position corresponding to the locking groove on the swing control pipe located at the swing allowable position. The swing control pipe located at the swing restraining position or the swing allowable position is substantially C-shaped with an outer peripheral portion fitted into the locking groove and an inner peripheral portion fitted into the connecting groove. The inner peripheral portion is elastically deformed in the diameter-expanding direction when a predetermined thrust load or more is applied to the inner peripheral portion. Tapered portion to disengage the inner portion from the connecting grooves by instrumented retaining ring, characterized in that it is fixed to the tool body Te.
As a result, the swing control pipe can be securely fixed to the swing restraint position or the swing allowable position with only a substantially C-shaped retaining ring, which is a simple structural component. Inadvertent displacement of the tube can be prevented.
Further, when a thrust load of a predetermined level or more is applied to the inner peripheral portion of the substantially C-shaped retaining ring, the inner peripheral portion is detached from the connecting groove of the tool body. Therefore, when the swing control tube is moved from the swing restraint position to the swing allowance position, or when it is moved from the swing allowance position to the swing restraint position, a thrust load exceeding a predetermined value is applied to the swing control tube itself. Therefore, it is possible to easily switch the position of the swing control pipe.

  The invention of claim 5 is the swing control pipe used for the excavation tool according to any one of claims 1 to 4.

According to the present invention, the tool main body is rotationally driven in a state where the swing control pipe is positioned at the swing restraint position to excavate the pilot hole whose inner diameter is the reference diameter, and then the excavation tool extracted from the pilot hole is removed. Move the swing control pipe to the swing allowable position, and then reinsert the drilling tool with the swing control pipe positioned at the swing allowable position into the pilot hole without rotating, and move the movable blade on the drill tool. When the tip portion of the drill reaches the position where the diameter of the pilot hole is desired to be increased, the excavation tool is driven to rotate. Then, the distal end side of the movable blade attached to the tool body moves outward in the radial direction of the tool body by the centrifugal force during rotation, so that the diameter to be excavated is widened and expanded to an arbitrary position of the pilot hole An enlarged diameter part can be formed.
Further, in the excavation tool, the movement of the movable blade body outward in the radial direction when forming the enlarged diameter portion is performed by a centrifugal force that acts when the tool body is rotated. A special drive mechanism for moving outward is not required, and the manufacturing cost of the drilling tool can be reduced by simplifying the configuration of the drilling tool.
Therefore, in the excavation tool, the hole can be reliably expanded and contracted at a low cost, and the hole having the enlarged diameter portion can be formed at a low cost.

It is a perspective view of the appearance of the excavation tool according to the first embodiment of the present invention in a state where the swing control pipe is located at the swing restraint position. FIG. 2 is a perspective view of a state in which a part of the swing control tube of the excavation tool illustrated in FIG. 1 is broken and a movable blade body inside the swing control tube is exposed. It is a longitudinal cross-sectional view of the excavation tool shown in FIG. It is AA sectional drawing of FIG. FIG. 4 is a view taken in the direction of arrow B in FIG. 3. It is a perspective view of the appearance of the excavation tool according to the first embodiment of the present invention in a state where the swing control pipe is located at the swing allowable position. FIG. 7 is a perspective view of a state in which a part of the swing control tube of the excavation tool illustrated in FIG. 6 is broken and a movable blade body inside the swing control tube is exposed. It is a longitudinal cross-sectional view of the excavation tool shown in FIG. It is C arrow line view of FIG. It is an external perspective view of the excavation tool according to the second embodiment of the present invention in a state where the swing control pipe is positioned at the swing restraint position. FIG. 11 is a perspective view of a state in which a part of the swing control tube of the excavation tool illustrated in FIG. 10 is broken and a movable blade body inside the swing control tube is exposed. It is a longitudinal cross-sectional view of the excavation tool shown in FIG. It is a front view of the ring-shaped spring member shown in FIG. It is DD sectional drawing of FIG. It is E arrow line view of FIG. It is a perspective view of the appearance of the excavation tool according to the second embodiment of the present invention in a state where the swing control pipe is located at the swing allowable position. FIG. 17 is a perspective view of a state in which a part of the swing control tube of the excavation tool illustrated in FIG. 16 is broken and a movable blade body inside the swing control tube is exposed. It is a longitudinal cross-sectional view of the excavation tool shown in FIG. It is F arrow line view of FIG. It is a perspective view of the appearance of the excavation tool according to the third embodiment of the present invention in a state where the swing control pipe is located at the swing restraint position. FIG. 21 is a perspective view of a state in which a part of the swing control tube of the excavation tool illustrated in FIG. 20 is broken and a movable blade body inside the swing control tube is exposed. It is a longitudinal cross-sectional view of the excavation tool shown in FIG. It is a front view of the substantially C-shaped retaining ring shown in FIG. It is GG sectional drawing of FIG. It is a H arrow line view of FIG. It is a perspective view of the appearance of the excavation tool according to the third embodiment of the present invention in a state where the swing control pipe is located at the swing allowable position. FIG. 27 is a perspective view of a state in which a part of the swing control tube of the excavation tool illustrated in FIG. 26 is broken and a movable blade body inside the swing control tube is exposed. It is a longitudinal cross-sectional view of the excavation tool shown in FIG. FIG. 29 is a view on arrow I of FIG. 28.

  Hereinafter, various embodiments of an excavation tool according to the present invention will be described in detail with reference to the drawings.

“First Embodiment”
First, a first embodiment of an excavation tool according to the present invention will be described with reference to FIGS.

  As shown in FIGS. 1 to 3, the excavation tool 1 of the present embodiment includes a tool main body 10, a pair of movable blade bodies 20 that are swingably attached to the outer periphery on the distal end side of the tool main body 10, and these A swing control tube 30 for restricting the swing motion of the pair of movable blade bodies 20 and a pin 40 for fixing the swing control tube 30 to the tool body 10 are provided.

  The tool body 10 is made of a material such as tool steel and is formed in a substantially cylindrical shape. As shown in FIG. 3, the tool body 10 includes a base end shaft portion 11 and an intermediate shaft portion 12 connected to a tip end (right end in FIG. 3) 11 a of the base end shaft portion 11 along the center axis O <b> 1. And a distal end shaft portion 13 connected to the distal end (right end in FIG. 3) 12a of the intermediate shaft portion 12.

  The proximal end shaft portion 11 has a thick cylindrical shape. As shown in FIG. 3, a female screw 111 is formed at the base end of the base end shaft portion 11 concentrically with the central axis O1. The female screw 111 is used to couple the proximal end of the tool body 10 to the distal end of a rotating rod extending from the rock drill. Further, as shown in FIGS. 1 and 2, the proximal end shaft portion 11 is formed with gripping surfaces 112 that are chamfered flat at two locations on the outer periphery. The gripping surface 112 is a surface that is gripped when the proximal shaft portion 11 is coupled to a rotating rod extending from the above-described rock drill.

  As shown in FIG. 3, the intermediate shaft portion 12 includes a first intermediate shaft portion 12b that is continuous with the distal end of the proximal end shaft portion 11, and a second intermediate shaft portion 12c that is continuous with the distal end of the first intermediate shaft portion 12b. I have. The first intermediate shaft portion 12 b and the second intermediate shaft portion 12 c constituting the intermediate shaft portion 12 are both cylindrical and concentric with the proximal end shaft portion 11. Further, the outer diameter of the first intermediate shaft portion 12 b is set to be smaller than that of the proximal end shaft portion 11. Further, the outer diameter of the second intermediate shaft portion 12c is set smaller than that of the first intermediate shaft portion 12b.

  A male screw 121 is engraved on the outer peripheral surface of the first intermediate shaft portion 12b. The male screw 121 is a screw portion into which a swing control tube 30 described later is screwed.

  A male screw 122 is engraved on the outer peripheral surface of the second intermediate shaft portion 12b. The male screw 122 is threadedly engaged with a female screw formed at the proximal end of the distal shaft portion 13 described later to form a state in which the distal shaft portion 13 is coupled to the distal end of the intermediate shaft portion 12.

  The tip shaft portion 13 is formed separately from the intermediate shaft portion 12. The distal end shaft portion 13 includes a cylindrical base end portion 13a concentric with the intermediate shaft portion 12, a distal end portion 13b extending from the distal end of the base end portion 13a along the direction of the central axis O1 of the tool body 10, and It has. The base end portion 13a is formed with a female screw 131 that is screwed with the male screw 122 on the outer periphery of the second intermediate shaft portion 12c described above. The distal shaft portion 13 is coupled to the distal end of the intermediate shaft portion 12 by screwing a female screw 131 at the proximal end to the male screw 122 of the second intermediate shaft portion 12c.

A flat movable blade mounting surface 132 is formed on the outer periphery on the distal end side of the distal end portion 13 b of the distal end shaft portion 13.
The movable blade mounting surface 132 is formed by chamfering the outer surface of the cylinder flat along the axial direction. In the case of this embodiment, as shown in FIG. 5, the movable blade mounting surfaces 132 are respectively provided on both outer side portions of the distal end portion 13 b sandwiching the central axis O <b> 1 of the tool body 10. Therefore, the distal end side of the distal end portion 13b has a flat plate shape.

  An excavation tip 51 made of a material such as cemented carbide harder than the tool body 10 is implanted on the distal end surface 13 c of the distal end shaft portion 13 which is the distal end surface of the tool body 10.

  In the case of the tool body 10 described above, the blow hole 101 is formed toward the distal end side of the tool body 10 from the inner bottom of the hole 114 in which the female screw 111 at the proximal end of the proximal end shaft portion 11 is formed. ing. As shown in FIG. 3, the blow hole 101 passes through the proximal end shaft portion 11, the intermediate shaft portion 12, and the distal end shaft portion 13 and opens to the distal end surface 13 c of the distal end shaft portion 13.

  Further, the tool body 10 of the present embodiment is provided with a communication passage portion 15 that communicates with an engagement hole 321 described later at two positions of a first position K1 and a second position K2 on the outer peripheral surface thereof. . The communication passage portion 15 is a groove into which a pin 40 described later can be inserted. In the case of this embodiment, the communication passage portion 15 is formed in an annular shape that goes around the outer periphery of the intermediate shaft portion 12.

  A first position K1 on the outer peripheral surface of the tool body 10 is a position corresponding to an engagement hole 321 on the swing control pipe 30 located at a swing restraint position P1 described later. Further, the second position K2 on the outer peripheral surface of the tool body 10 is a position corresponding to an engagement hole 321 on the swing control pipe 30 located at a swing allowable position P2 described later.

  As shown in FIG. 5, the movable blade body 20 has an inner surface 20 a that faces the movable blade mounting surface 132 formed on a flat surface. Further, the outer surface 20 b of the movable blade body 20 positioned on the opposite side to the movable blade mounting surface 132 is formed as an arc surface having the same diameter as the outer peripheral surface of the base end portion 13 a of the distal end shaft portion 13.

  The base end of the movable blade body 20 is coupled to the movable blade mounting surface 132 so as to be rotatable around the pivot Z1 by a pivot Z1 perpendicular to the movable blade mounting surface 132. In other words, the base end of the movable blade body 20 is coupled to the movable blade mounting surface 132 so as to be swingable along the movable blade mounting surface 132. The movable blade body 20 whose base end is coupled to the moving blade mounting surface 132 so as to be rotatable around the pivot axis Z <b> 1 can be moved outward in the radial direction of the tool body 10 by centrifugal force when the tool body 10 rotates. It has become. In addition, as shown by arrows X2 and X3 in FIG. 9, the pair of movable blades 20 arranged on both sides of the tip shaft portion 13 are oscillating in directions opposite to each other due to centrifugal force when the tool body 10 rotates. It is couple | bonded with the front-end | tip shaft part 13 so that it may become.

In addition, the movable blade body 20 has a plurality of excavation tips 51 implanted on the tip surface 20c. The excavation tip 51 implanted in the distal end surface 20 c of the movable blade body 20 is the same as the excavation tip 51 implanted in the distal end surface 13 c of the distal end shaft portion 13.

The swing control tube 30 is formed in a cylindrical structure that fits on the outer periphery of the tool body 10 so as to be slidable in the central axis direction of the tool body 10 (in the direction of arrow X1 in FIG. 3).
The swing control tube 30 of the present embodiment can move between a swing restraint position set on the tool body 10 and a swing allowable position. Here, the swing restraint position is a position indicated by reference numeral P1 in FIGS. Further, the swing allowable position is a position indicated by a symbol P2 in FIG. The swing allowable position P2 is a position retracted by a predetermined distance L1 from the swing restraint position P1 along the central axis of the tool body 10.

  The swing control tube 30 shown in FIGS. 1 to 3 is in a state in which a distal end cylindrical portion (cylinder portion located at the right end in FIG. 3) 31 is positioned at the swing restraint position P1. In this state, the distal end cylindrical portion 31 of the swing control tube 30 covers the movable blade body 20 to restrict the distal end side of the movable blade body 20 from moving outward in the radial direction of the tool body 10.

  On the other hand, the swing control tube 30 shown in FIGS. 6 to 8 is in a state where the distal end cylindrical portion 31 is located at the swing allowable position P2. In this state, the distal end cylindrical portion 31 of the swing control tube 30 is retracted from above the movable blade body 20, and the distal end side of each movable blade body 20 is the tool body 10 as indicated by arrows X2 and X3 in FIG. It is allowed to move outward in the radial direction.

  In the case of the present embodiment, as shown in FIG. 3, on the inner periphery on the proximal end side of the swing control tube 30, a female screw that engages with a male screw 121 engraved on the outer periphery of the first intermediate shaft portion 12b. 301 is formed. Therefore, the swing control tube 30 can be moved in the axial direction of the tool body 10 by rotating the swing control tube 30 relative to the first intermediate shaft portion 12b. As shown in FIG. 1, a flat grip surface 303 is formed on the outer periphery of the swing control tube 30 to be gripped when the swing control tube 30 is rotated.

  In the case of the present embodiment, as shown in FIGS. 1 to 3, the proximal end side cylinder portion 32 of the swing control tube 30 screwed to the outer periphery of the tool body 10 has an axis (center axis) of the tool body 10. An engagement hole 321 is provided that penetrates in a direction orthogonal to O1). In the case of this embodiment, the engagement holes 321 are provided at two locations on the base end side cylindrical portion 32.

The pin 40 that fixes the swing control tube 30 to the tool body 10 is a pin that fits tightly into an engagement hole 321 formed through the proximal end side cylinder portion 32 of the swing control tube 30.
When the pin 40 is driven into the engagement hole 321 of the swing control pipe 30 located at the swing restraint position P1 as shown in FIG. 1, as shown in FIG. The swing control pipe 30 is fixed to the swing restraint position P1 so as to extend in a direction orthogonal to the central axis O1 of the tool body 10 across the connecting passage portion 15 at the position K1.
When the pin 40 is driven into the engagement hole 321 of the swing control pipe 30 located at the swing allowable position P2 as shown in FIG. 6, as shown in FIG. The swing control tube 30 is fixed to the swing allowable position P2 extending across the communication passage 15 at the second position K2 in a direction orthogonal to the central axis O1 of the tool body 10.

In the excavation tool 1 of the first embodiment described above, when the tool body 10 is rotationally driven with the swing control pipe 30 positioned at the swing allowable position P2 as shown in FIG. 8, the centrifugal force at that time Thus, since the distal end side of the movable blade body 20 moves outward in the radial direction of the tool main body 10, the tool main body 10 is rotationally driven in a state where the swing control pipe 30 is positioned at the swing restraining position P1. Thus, a hole having a large diameter can be excavated.
Accordingly, the tool body 10 is rotationally driven in a state where the swing control pipe 30 is positioned at the swing restraint position P1, and after excavating the pilot hole whose inner diameter is the reference diameter, the excavation tool shaken out of the pilot hole is shaken. The motion control tube 30 is moved to the swing allowable position P2. Next, the excavation tool 1 with the swing control pipe 30 positioned at the swing allowable position P2 is not rotated and is reinserted into the pilot hole, and the tip of the movable blade 20 on the excavation tool 1 is positioned above the pilot hole. Is reached, the excavation tool 1 is driven to rotate. Then, the distal end side of the movable blade body 20 attached to the tool body 10 moves outward in the radial direction of the tool body 10 by the centrifugal force at the time of rotation. An expanded diameter portion can be formed.
That is, in the excavation tool 1 of the first embodiment, a single excavation tool 1 can form a hole having an enlarged diameter portion. Further, since the movable blade body 20 is moved outward in the radial direction when forming the enlarged diameter portion by centrifugal force acting when the tool body 10 is rotated, the movable blade body 20 is moved radially outward. A special drive mechanism for moving the drilling tool 1 is not required, and the manufacturing cost of the drilling tool 1 can be reduced by simplifying the configuration of the drilling tool 1. Further, since the swing control tube 30 is positioned at the swing restraining position P1, swinging of the distal end side of the movable blade body 20 in the radially outward direction can be surely restricted. It is possible to prevent the diameter of the hole excavated by swinging the body 20.
Therefore, in the excavation tool 1 of the first embodiment, the hole can be reliably expanded and contracted at a low cost, and the hole having the enlarged diameter portion can be formed at a low cost.

  Further, in the excavation tool 1 of the first embodiment, the swing control pipe 30 positioned at the swing restraint position P1 or the swing allowable position P2 is a simple structural component in the engagement hole 321 on the swing control pipe 30. When the pin 40 is driven, the pin 40 extends across the swing control tube 30 and the tool body 10 in a direction perpendicular to the central axis O1 of the tool body 10, and the swing control tube 30 Is fixed at the swing restraint position P1 or the swing allowable position P2. That is, in the excavation tool 1 according to the first embodiment, the swing control pipe 30 is securely fixed to the swing restraint position P1 or the swing allowable position P2 on the tool body 10 with only the pin 40 which is a simple structural component. It is possible to prevent the swing control pipe 30 from being inadvertently displaced during excavation work.

“Second Embodiment”
Next, 2nd Embodiment of the excavation tool which concerns on this invention is described with reference to FIGS.

  As shown in FIGS. 10 to 13, the excavation tool 1 </ b> A of the present embodiment includes a tool main body 10 </ b> A, a pair of movable blade bodies 20 that are swingably attached to the outer periphery on the tip side of the tool main body 10 </ b> A, A swing control tube 30A for restricting the swing motion of the pair of movable blade bodies 20 and a ring-shaped spring member 60 for fixing the swing control tube 30A to the tool body 10A are provided.

  The tool body 10A of the second embodiment is an improvement of a part of the tool body 10 of the first embodiment, and includes a connecting groove 16 instead of the communication passage portion 15 in the tool body 10 of the first embodiment. It is a thing.

  The tool body 10A of the second embodiment may have the same configuration as that of the tool body 10 of the first embodiment except for the point provided with the connecting groove 16, and the configuration common to the first embodiment is the first embodiment. The same reference numerals are used and description thereof is omitted.

  The connecting groove 16 provided in the tool body 10A of the second embodiment is a groove that goes around the outer periphery of the intermediate shaft portion 12 of the tool body 10A. As shown in FIG. 11, three connecting grooves 16 are provided at two positions, the first position K1 and the second position K2, respectively, on the outer peripheral surface of the tool body 10A. Here, the first position K1 is a position corresponding to the locking groove 322 on the swing control pipe 30A located at the swing restraint position P1. The second position K2 is a position corresponding to the locking groove 322 on the swing control pipe 30 located at the swing allowable position P2.

  The movable blade body 20 attached to the tool main body 10A has the same configuration as that of the first embodiment, and the configuration common to the first embodiment is denoted by the same reference numeral as that of the first embodiment, and the description thereof is omitted. .

  The swing control pipe 30 </ b> A is provided with three locking grooves 322 that circulate around the inner periphery of the base end side cylinder part 32 on the inner periphery of the base end side cylinder part 32. The three locking grooves 322 are provided at regular intervals in the central axis direction of the swing control pipe 30A.

  The swing control tube 30A of the second embodiment is equipped with a locking groove 322 instead of the engagement hole 321 in the swing control tube 30 of the first embodiment. In the swing control tube 30A, the configuration other than the locking groove 322 may be the same as that of the swing control tube 30 of the first embodiment, and the configuration common to the first embodiment is the same as that of the first embodiment. The description is omitted.

As shown in FIG. 13, the ring-shaped spring member 60 is a ring having a simple structure in which convex arc portions 61 and concave arc portions 62 are alternately arranged in the circumferential direction.
The convex arc portion 61 is formed in a convex arc shape outward in the radial direction of the ring, and is a portion that fits into the locking groove 322 of the swing control pipe 30A as shown in FIG.
The concave arc portion 62 is formed in a convex arc shape inward in the radial direction of the ring, and is a portion that fits into the connecting groove 16 of the tool body 10 as shown in FIG.

  The swing control tube 30 positioned at the swing restraint position P1 or the swing allowable position P2 is fixed to the tool body 10 by a ring-shaped spring member 60 as shown in FIGS.

  The ring-shaped spring member 60 according to the present embodiment is configured so that when a predetermined thrust load or more is applied to the concave arc portion 62, each arc shape is such that the concave arc portion 62 is pulled up radially outward and detached from the coupling groove 16. The part is elastically deformed.

  Therefore, when the swing control tube 30A is moved from the swing restraint position P1 to the swing allowance position P2, or when it is moved from the swing allowance position P2 to the swing restraint position P1, the swing control tube 30A itself. When a predetermined thrust load or more is applied, the coupling state of the swing control tube 30A to the tool body 10A via the ring-shaped spring member 60 can be released.

In the excavation tool 1A of the second embodiment described above, similarly to the excavation tool 1 of the first embodiment, the hole can be reliably expanded and contracted while being inexpensive, and the hole having the enlarged diameter portion is inexpensive. Can be formed.
In the excavation tool 1A of the second embodiment, the swing control tube 30A is securely fixed to the swing restraint position P1 or the swing allowable position P2 only by the ring-shaped spring member 60 that is a simple structural component. Thus, it is possible to prevent the rocking control pipe 30A from being unintentionally displaced during excavation work.
Further, in the ring-shaped spring member 60, when a predetermined thrust load or more is applied to the concave arc portion 62, the concave arc portion 62 is detached from the connecting groove 16 of the tool body 10. Therefore, when the swing control tube 30 is moved from the swing restraint position P1 to the swing allowance position P2, and when the swing control tube 30 is moved from the swing allowance position P2 to the swing restraint position P1, the swing control tube 30 itself. It is sufficient to apply a thrust load greater than or equal to a predetermined value to the position of the swing control tube 30.

“Third Embodiment”
Next, 3rd Embodiment of the excavation tool which concerns on this invention is described with reference to FIGS.
As shown in FIGS. 20 to 22, the excavation tool 1B of the present embodiment includes a tool body 10B, a pair of movable blades 20 that are swingably attached to the outer periphery on the tip side of the tool body 10B, and these A swing control tube 30B for restricting the swing motion of the pair of movable blade bodies 20 and a substantially C-shaped retaining ring 70 for fixing the swing control tube 30B to the tool body 10B are provided.

  The tool main body 10B of the third embodiment is an improvement of a part of the tool main body 10 of the first embodiment, and instead of the connecting passage portion 15 in the tool main body 10 of the first embodiment, the outer periphery of the intermediate shaft portion 12 is. Is provided with a connecting groove 17.

  The tool body 10B of the third embodiment may have the same configuration as that of the tool body 10 of the first embodiment except for the point provided with the connecting groove 17, and the configuration common to the first embodiment is the first embodiment. The same reference numerals are used and description thereof is omitted.

  The connecting groove 17 provided in the tool body 10B of the third embodiment is a groove that goes around the outer periphery of the intermediate shaft portion 12 of the tool body 10B. As shown in FIG. 21, three connecting grooves 17 are provided at two positions, the first position K1 and the second position K2, respectively, on the outer peripheral surface of the tool body 10B. Here, the first position K1 is a position corresponding to the locking groove 323 on the swing control pipe 30B located at the swing restraint position P1. The second position K2 is a position corresponding to the locking groove 323 on the swing control pipe 30 located at the swing allowable position P2.

  The movable blade body 20 attached to the tool body 10B has the same configuration as that of the first embodiment, and the same configuration as that of the first embodiment is denoted by the same reference numeral as that of the first embodiment, and the description thereof is omitted. .

  The swing control pipe 30B is provided with three locking grooves 323 that circulate around the inner periphery of the base end side cylindrical portion 32 on the inner periphery of the base end side cylindrical portion 32 thereof. The three locking grooves 323 are provided at regular intervals in the central axis direction of the swing control pipe 30B.

  The swing control tube 30B of the second embodiment is provided with a locking groove 323 instead of the engagement hole 321 in the swing control tube 30 of the first embodiment. In the swing control tube 30B, the configuration other than the locking groove 323 may be the same as the configuration of the swing control tube 30 of the first embodiment, and the configuration common to the first embodiment is the same as that of the first embodiment. The description is omitted.

  As shown in FIGS. 23 and 24, the retaining ring 70 has a substantially C shape with a part in the circumferential direction cut off, and an outer peripheral portion 71 that fits into the inner locking groove 323 of the swing control pipe 30 </ b> B. And an inner peripheral portion 72 that fits into the connecting groove 17 on the outer periphery of the intermediate shaft portion 12. In addition, when a predetermined thrust load or more acts on the inner peripheral portion 72 of the retaining ring 70 of the present embodiment, the inner peripheral portion 72 is elastically deformed in the diameter increasing direction. Is provided with a taper portion T for detaching from the connecting groove 17.

  Therefore, when the swing control tube 30B is moved from the swing restraint position P1 to the swing allowance position P2, or when it is moved from the swing allowance position P2 to the swing restraint position P1, the swing control tube 30B itself If a predetermined thrust load or more is applied, the coupling state of the swing control pipe 30B to the tool body 10B via the retaining ring 70 can be released.

In the excavation tool 1B of the third embodiment described above, similarly to the excavation tool 1 of the first embodiment, the hole can be reliably expanded and contracted while being inexpensive, and the hole having the enlarged diameter portion is inexpensive. Can be formed.
Further, in the excavation tool 1A of the second embodiment, the swing control pipe 30B can be reliably moved to the swing restraint position P1 or the swing allowable position P2 only by the substantially C-shaped retaining ring 70 which is a simple structural component. The rocking control pipe 30B can be prevented from being inadvertently displaced during excavation work.
The substantially C-shaped retaining ring 70 detaches from the connecting groove 17 of the tool body 10 when a predetermined thrust load or more is applied to the inner peripheral portion 72. Therefore, when the swing control tube 30 is moved from the swing restraint position P1 to the swing allowance position P2, and when it is moved from the swing allowance position P2 to the swing restraint position P1, the swing control tube 30B itself. It is sufficient to apply a thrust load greater than or equal to a predetermined value to the position of the swing control tube 30B.

  In addition, the excavation tool of this invention is not limited to each above-mentioned embodiment, A component can be changed and improved in the range which does not deviate from the main point of this invention.

DESCRIPTION OF SYMBOLS 1,1A, 1B Excavation tool 10,10A, 10B Tool main body 15 Communication channel | path part 16,17 Connection groove | channel 20 Movable blade 30,30A, 30B Oscillation control pipe 32 Base end side cylinder part 40 Pin 31 Tip cylinder part 51 Drilling tip 60 Ring-shaped spring member 61 Convex arc part 62 Concave arc part 70 Retaining ring 71 Outer part 72 Inner part 132 Movable blade mounting surface 321 Engaging hole 322 Engaging groove 323 Engaging groove K1 First position K2 Second Position P1 Swing restraint position P2 Swing allowable position

Claims (5)

A tool body having a generally cylindrical shape, a movable blade mounting surface chamfered flat along the axial direction on the outer periphery on the tip side, and a drilling tip implanted in the tip surface;
An excavation tip is implanted on the distal end surface, and a proximal end is coupled to the movable blade attachment surface so as to be swingable along the movable blade attachment surface, and the distal end side is caused by centrifugal force when the tool body rotates. A movable blade that is movable radially outward of the tool body;
The tip is formed in a cylindrical structure that fits on the outer periphery of the tool body so as to be slidable in the direction of the central axis of the tool body, and the tip is positioned when the tip cylinder is located at a swing restraint position set on the tool body. The cylindrical portion covers the movable blade body and restricts the distal end side of the movable blade body from moving outward in the radial direction of the tool main body, and the distal cylindrical portion extends along the central axis of the tool main body. A swing control pipe that allows the distal end side of the movable blade body to move outward in the radial direction of the tool body when positioned at a swing allowable position that is retracted by a predetermined distance from the swing restraint position;
An excavation tool comprising: An engagement hole penetrating in a direction orthogonal to the axis of the tool main body is provided in the base end side cylindrical portion of the swing control pipe fitted to the outer periphery of the tool main body,
The tool main body is located on the outer peripheral surface thereof at a first position corresponding to the engagement hole on the swing control pipe positioned at the swing restraining position and at the swing allowable position. A communication passage portion communicating with the engagement hole is provided at two positions, the second position corresponding to the engagement hole on the swing control pipe,
The swing control pipe located at the swing restraining position or the swing allowable position is formed by a pin that is driven into the engagement hole so as to straddle the engagement hole and the communication passage portion whose positions are aligned. The excavation tool according to claim 1, wherein the excavation tool is fixed to the tool body. On the inner periphery of the base end side cylindrical portion of the swing control pipe that fits to the outer periphery of the tool body, a locking groove is provided that goes around the inner periphery of the base end side cylindrical portion,
The tool body is located on the outer peripheral surface thereof at a first position corresponding to the locking groove on the swing control pipe positioned at the swing restraining position, and at the swing allowable position. A coupling groove that circulates around the outer periphery of the tool body is provided at two positions, the second position corresponding to the locking groove on the swing control pipe,
The swing control pipe positioned at the swing restraining position or the swing allowable position is formed in an outwardly convex arc shape and is fitted with the engaging groove, and an inwardly convex circle. When the concave arc portions formed in an arc shape and alternately fitted in the circumferential direction in the circumferential direction are arranged in the circumferential direction and a thrust load of a predetermined level or more is applied to the concave arc portion, the concave arc portion is separated from the coupling groove. The excavation tool according to claim 1, wherein each arc portion is fixed to the tool body by a ring-shaped spring member that is elastically deformed so as to be detached. On the inner periphery of the base end side cylindrical portion of the swing control pipe that fits to the outer periphery of the tool body, a locking groove is provided that goes around the inner periphery of the base end side cylindrical portion,
The tool body is located on the outer peripheral surface thereof at a first position corresponding to the locking groove on the swing control pipe positioned at the swing restraining position, and at the swing allowable position. A coupling groove that circulates around the outer periphery of the tool body is provided at two positions, the second position corresponding to the locking groove on the swing control pipe,
The swing control pipe located at the swing restraining position or the swing allowable position is formed in a substantially C shape in which an outer peripheral portion is fitted in the locking groove and an inner peripheral portion is fitted in the connecting groove. And a taper that causes the inner peripheral portion to be elastically deformed in the diameter-expanding direction and to disengage the inner peripheral portion from the coupling groove when a predetermined or more thrust load is applied to the inner peripheral portion. The excavation tool according to claim 1, wherein the excavation tool is fixed to the tool main body by a retaining ring equipped with a portion.   A swing control pipe, which is the swing control pipe used in the excavation tool according to any one of claims 1 to 4.

Images