JP6700524B2 - Core drill and drilling method - Google Patents

Description

  The present invention relates to a core drill used for drilling a concrete structure, particularly a core drill suitable for drilling a deep hole, and a drilling method using the core drill.

  The core drill is generally a base that is removably fixed to a concrete structure, a column that is vertically installed on the base, a rack is attached to the column, a slide block that is vertically movable on the column, and the rack that meshes with the rack. A feed motor for rotating and driving a pinion built in a slide block, a rotation motor attached to the slide block, and a core bit removably attached to the drive shaft of the rotation motor in parallel with the support column. A coupling that is attached to the drive shaft, a bit portion that has a diamond tip attached to the tip by welding or brazing, and a tube that is interposed between the coupling and the bit portion and that connects the coupling portion to each other. There are a one-body type in which a tube and a bit part are integrally formed, and a split type in which these three parts are connected by screw connection (Patent Document 1).

  Conventionally, when drilling a deep hole in a concrete structure with a core drill, when using a long one-body type core bit, or when using a split type core bit, the drilling operation is temporarily interrupted during drilling and the coupling is removed. Although a tube was added, when the former long core bit is used, the stroke of the slide block also becomes longer, the column becomes longer, the core drill becomes larger, and the core bit of the core bit is connected to the drive shaft. Since the core bit supported in a cantilever shape is bent and the diamond tip at the tip end is easily shaken at the start of cutting, especially when the hole is drilled horizontally. Therefore, in the past, a guide was applied to the tip of the core bit to guide the tip of the core bit so as not to move, and the hole was drilled.

  In the latter core bit that adds tubes, the tip of the core bit is less likely to be shaken at the start of cutting, but since the tubes are added during drilling, work must be interrupted and remote control is not possible.

JP-A-2005-199405

  The present invention, when making a deep hole in a concrete structure, a stable cutting can be performed without using a guide, and further, a core bit capable of performing a drilling operation by remote control without adding a tube during drilling, An object of the present invention is to provide a drilling method using a core bit.

  According to a first aspect of the present invention, there is provided a support column provided with a rack, a pinion reciprocally attached to the support column, which meshes with the rack, a slide block including a feed motor for rotationally driving the pinion, and the slide. In a core drill comprising a head portion that is integral with a block, a core bit that is supported by the head portion in parallel with a support, and a rotary motor that is attached to the head portion and that rotationally drives the core bit, the core bit is attached to the head portion. It is slidably fitted, and is arranged in the head portion at a plurality of positions on the inner circumference around the core bit at appropriate intervals in the circumferential direction, and each of them is at least in the radial direction, the circumferential direction, and the core bit axial direction. The chuck claws that can be moved back and forth in the radial direction, and that can be orbited in the circumferential direction, and the chuck claws are pushed inward in the radial direction from positions radially separated from the core bit, and are crimped to the core bit to form the core bit The rotation motor is integrated in the rotation direction, the feed direction, and the core bit axial direction, and includes the pressing motor that can release the pressing into the core bit and the rotation motor. Circulating means for rotating the chuck claws in the circumferential direction as a drive source, and a shaft of the core bit attached to the head part by the feed motor as a drive source in a state where each chuck claw is pressure-bonded to the core bit. It is characterized by having a feeding means for feeding in a direction.

According to a second aspect of the present invention, the chuck claw of the first aspect of the invention can be moved back and forth along the core bit in the axial direction of the core bit, and the pushing means is attached to the head portion so that the chuck claw is attached to the core bit. An actuator that moves back and forth in the axial direction, a rotating member that is arranged around the core bit coaxially with the core bit, and that rotates around the core bit by using the feed motor of the rotating means as a drive source, and the chuck claw. Characterized by having a wedge mechanism formed,
According to a third aspect of the invention, in the invention according to the first or second aspect, there is provided a separating means for separating the chuck claw from the core bit in the radial direction when the pressing by the pressing means is released. To do.

  According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, a pressing member that is arranged on the base side of the support column and is capable of advancing and retracting in the radial direction, and a core bit formed by the chuck claws. In the state where the presser foot is released, the presser tool is characterized by having an actuator that moves the presser tool inward in the radial direction and presses and holds the core bit.

  The invention according to claim 5 relates to a method for piercing a concrete structure using the core drill according to claim 1, wherein the chuck claws are radially inwardly pushed by a pushing means and a tip side portion of the core bit is provided. When the chuck jaws reach the lower limit position after the start of cutting, the core bit is rotated and the core bit is rotated to feed while rotating the core bit with the tip side held. Once the pushing by the means is released, then the feed motor is reversely rotated to retract the chuck claw along the core bit, and after retracting to the upper limit position, the chuck claw is fixed by crimping to the core bit by the pressing means, and then the rotation is performed. The core bit is rotated by driving the motor and the feed motor to continue drilling, and when the chuck claw reaches the lower limit position with the core bit, the pushing by the pushing means is released, and the above procedure is repeated after the release. And

  In the present invention, the upper limit position and the lower limit position represent the forward limit position and the backward limit position when making a lateral hole. The same applies to the following.

  According to the first and fifth aspects of the invention, when punching holes in the concrete structure, the chuck claws are pushed inward in the radial direction by the pushing means, and the rotary claws are chucked by pressing the core bits by the rotary motor. This is done by feeding the feed motor as a driving source while orbiting as a driving source.However, at the beginning of cutting, the chuck claws are pressed against the tip of the core bit from a plurality of surrounding points to hold the tip. Even with a long core bit, the tip of the core bit will not be shaken, stable cutting can be performed even with a horizontally oriented core bit, and when the chuck claw that holds the core bit fixed reaches the lower limit position, the chuck claw is moved to the upper limit position, By changing the holding position to the core bit, it is possible to perform deep hole drilling work using a long core bit without adding tubes, and control of the rotation motor, feed motor, pushing means, etc. can be performed by remote operation. Therefore, there is an effect that the drilling work by the core bit according to the present invention can be performed by remote control.

  According to the invention of claim 2, the chuck claw is advanced and pushed down along the core bit by the actuator, is pushed inward in the radial direction by the wedge action between the chuck and the orbiting member, and is crimped and fixed to the core bit, while the actuator is driven by the actuator. By retracting along the core bit and being pulled up, the core bit is separated from the orbiting member, and the wedge action is canceled, so that the pressure contact with the core bit is released.

  According to the third aspect of the present invention, the chuck claw, which has been released from being pushed by the pushing means, can be forcibly separated from the core bit by the separating means, whereby the chuck claw can smoothly advance and retreat along the core bit. Become.

  After the drilling work, the chuck claws move to the upper limit position by the reverse rotation of the feed motor while the core bit is fixed, and then the holding to the core bit is released, and the feed motor is driven in the released state. Repeat the procedure to move to the lower limit position on the tip side of the core bit, hold the core bit again at the lower limit position, and move toward the upper limit position.However, when the chuck claw releases the holding of the core bit, it is necessary to perform vertical hole drilling work. If the core bit is oriented vertically, it may slip into the vertical hole drilled. This problem can be solved by pushing the holding tool forward toward the core bit and pressing and holding the core bit, as in the invention according to claim 4.

The partial cross section front view of a core drill. Sectional drawing of the head part of the core drill shown in FIG. Sectional drawing in the AA line of FIG. Schematic which shows another example of a pushing means. FIG. 3 is a plan view of the presser foot arranged on both sides of the core bit.

Hereinafter, an embodiment of a core drill according to the present invention will be described with reference to the drawings.
FIG. 1 shows an example in which the core drill 1 is used in a vertical orientation to form a vertical hole, and the vertical orientation will be described below in the vertical direction. When used as above, the up-down direction described below is the left-right direction.

  The core drill 1 is detachably fixed to a concrete structure 2 by a well-known method, a base 5 vertically installed on the base 3 and a rack 5 attached thereto, and a vertically movable mount on the pillar 5. The slide block 6 includes a head portion 7 laterally protruding from the slide block 6 and integrally formed with the block 6, and a core bit 8 penetrating the head portion 7 in a vertically movable manner. ..

  Although not shown in the figure, the slide block 6 has a built-in pinion that meshes with the rack 4 of the support column 5. The pinion is rotatably driven by the feed motor 9 attached to the slide block 6 to roll and slide the rack 4. The block 6 is moved up and down along with the head portion 7 along the column 5 to advance and retreat, and in the cylindrical main body 7a of the head portion 7 through which the core bit 8 passes so as to move upward and downward, as shown in FIGS. 2 and 3. As described above, an annular member 11 which is coaxial with the main body 7a and into which the core bit 8 is inserted with play is disposed, and an inner peripheral surface of the annular member 11 is provided with a circumferential groove 12 on the same inner circumference. The head portion 14a of the chuck claw 14 which is formed in three places (or four or more places) at regular intervals in the direction and has a circular cross section in each circumferential groove 12 is formed in the radial direction. It can be retracted, but its movement in the circumferential direction is regulated and fitted.

  The chuck claw 14 in which the head portion 14a is fitted in the circumferential groove 12 and is supported by the annular member 11 extends not only in the head portion but also in an arc shape in cross section and extends around the core bit 8 along the core bit 8. The lower outer peripheral portion projects outward from the chuck claws 8, and the projecting portion 14b is formed in the shape of an arrow in a vertical section whose diameter is gradually reduced downward, and the outer peripheral surface is a tapered surface 14c.

  In the main body 7a of the head portion 7, there are also a pushing means for pushing the chuck claw 14 inward in the radial direction, a separating means for pushing the chuck claw 14 outward in the radial direction and separating it from the core bit 8, and the chuck claw 14 A part of the circling means for circling in the inner circumferential direction around the core bit 8 is arranged, and each of these means will be described in detail below.

  Below the annular member 11, the orbiting member 17 is coaxially attached to the main body 7a and the annular member 11 and is rotatably attached to the main body 7a via ball bearings 16a and 16b. A wedge mechanism composed of a tapered surface 17a formed by gradually expanding upward on the peripheral surface and a tapered surface 14c formed on the outer peripheral surface of the protruding portion 14b of the chuck claw 14 and the chuck claw 14. An air cylinder (may be a hydraulic cylinder) 18 as an actuator for moving up and down is formed, and the air cylinder 18 is formed in a circumferential shape around the core bit 8 on the upper side of the main body.

  The piston 19 of the air cylinder 18 also has a cylindrical shape, and the upper portion 19a of the outer cylinder portion 7b constitutes an upper portion of the main body. 7b is slidably fitted in the circumferential groove 21 between the inner tubular portion 7c and the inner tubular portion 7c forming a circumferential groove 21 and compressed into an annular space 22 between the outer tubular portion 7b and the piston upper portion 19a. When air is supplied, the piston 19 is pushed down.

  The piston 19 protruding downward from the circumferential groove 21 forms an annular space 23 between the piston 19 and the outer cylindrical portion 7b. When compressed air is sent to the space 23, the compressed air is discharged from the space 22. However, the piston 19 is adapted to rise, and the projecting portion at the lower end of the piston is connected to the annular member 11 via a ball bearing 24, and freely rotates with the annular member 11, but it is integrated vertically. It is designed to go up and down.

  The pushing means has the air cylinder 18 and the wedge mechanism as described above, and when the piston 19 is lowered by the switching of the switching valve (not shown) of the air cylinder 18, the annular member 11 moves in three circumferential directions via the ball bearing 24. It is pushed down together with the chuck claw 14 in place. When the chuck claws 14 are pushed down, the chuck claws 14 are pushed inward in the radial direction by the wedge action of the tapered surfaces 14c and 17a forming the wedge mechanism, and the entire arc-shaped inner peripheral surface of each chuck claw 14 ( The inner peripheral surface has the same radius of curvature as the outer peripheral surface of the core bit.) The core bit 8 is pressed against the core bit 8 in a state of being in close contact with the core bit 8, so that the orbiting member 17, the chuck claws 14 and the core bit 8 are fixed and integrated. It

  The fixing of the core bit 8 is performed by raising the piston 19 by the air cylinder 18 and raising the chuck claw 14 via the annular member 11, and the rise of the chuck claw 14 causes the taper surface 14c of the chuck claw 14 to move around. The taper surface 17a of the roller 17 is slid up and the diameter is increased, whereby the chuck claw 14 is separated from the bit 8 in the radial direction. In the figure, reference numeral 25 denotes a guide pin which projects radially from the chuck claw head 14a through the annular member 11 and guides the radial movement of the chuck claw 14.

  FIG. 4 shows another example of the pushing means. An air cylinder 28, which is an actuator attached to the main body 7a, is connected to each of the chuck claws 27 having an arcuate cross section, and an L-shaped hook shape. A pressing portion 27a that presses the tubular portion 29a of the circumferential member 29 having a cross section from the outer peripheral side is integrally formed. When the chuck claw 27 is pushed inward in the radial direction by the air cylinder 28, the chuck claw 27 is pressed against the core bit 8. While press-fitting, the pressing portion 27a presses the rotating member 29 from the outer peripheral side, whereby the rotating member 29, the chuck claw 27 and the core bit 8 are integrally fixed.

  The separating means is composed of a c-ring-shaped wire spring 31, which is fitted into a circumferential groove 32 formed on the inner peripheral surface of the chuck claw head 14a, and when the chuck claw 14 is pressed against the core bit 8 from three sides, a wire is formed. The spring 31 is also reduced in diameter and pressed against the core bit 8. However, as the chuck claw 14 is lifted by the air cylinder 18 and the pressure applied to the core bit 8 is weakened, the diameter is expanded and the chuck claw 14 is pushed outward in the radial direction. 8 to promote separation.

  The orbiting means has a rotary motor 34 that is mounted side by side on the main body 7a of the head portion 7 in parallel with the main body 7a. A drive gear 35 of the rotary motor 34 and a gear formed on the outer peripheral surface of the orbiting member 17 are provided. The intermediate gear 36 is interposed between the core bit 8 and the rotating member 34, and the rotating member 34 rotates around the core bit 8 via the gear transmission. By this rotation, the above-mentioned wedge mechanism presses the core bit 8 and the winding member 17 against each other, and the core bit 8 rotates via the chuck claws 14 which are in a fixed state. In the present embodiment, the rotary motor 34, the gear transmission, and the orbiting member 17 having the tapered surface 17a that is a part of the wedge mechanism constitute the orbiting means of the chuck claw 14. By the circulation of the chuck claws 14, the annular member 11 also revolves around the piston 19 via the ball bearings 24.

  The feed of the core bit 8 at the time of punching is performed by driving the feed motor 9 shown in FIG. That is, the pinion is rotationally driven by the feed motor 9, the rack 4 rolls, and the slide block 6 descends along with the head portion 7 along the column 5. As the head portion 7 descends, the orbiting member 17 in the head portion descends together with the core bit 8 via the chuck pawls 14 that are pressure bonded to the orbiting member 17 and the core bit 8. In the present embodiment, the feed motor 9, the pinion rack 4, the slide block 6, the head portion 7, the orbiting member 17 supported by the head portion 7, the wedge mechanism and the like directly and indirectly feed the chuck claws 14. Is composed of. When the feed motor 9 is reversely rotated in a state where the chuck claw 14 is pressed and fixed to the core bit 8 by the wedge action, the core bit 8 is raised together with the slide block 6 and the head 7 contrary to the above.

  When the chuck claw 14 is pulled up by the air cylinder 18, is separated from the core bit 8 in the radial direction, and the feed motor 9 is reversely rotated in the state where the fixation by the pressure contact with the core bit 8 is released, the head portion 7 causes the core bit 8 to move. Rise along Core Bit 8 with no accompanying.

  FIG. 5 shows a presser pad 41 as a presser which is arranged so that the core bit 8 can be pressed in from both sides in the diametrical direction. Each presser pad 41 is at the same level as the base 3 and The air cylinders 42 are arranged at symmetrical positions in the diametrical direction with the core bit 8 sandwiched therebetween so that the core bit 8 can be moved forward and backward in the diametrical direction. One of the pressing pads may be fixed without being connected to the air cylinder.

  The core drill 1 of the present embodiment is configured as described above, and the concrete structure 2 is drilled as follows.

  The base 3 is fixed to the concrete structure 2, the long core bit 8 is inserted into the head portion 7, and the tip of the core bit is landed on the concrete structure 2. Then, the feed motor 9 is controlled to control the switching valve (not shown) of the air cylinder 18 while the slide block 6 is kept at a position slightly above the lower limit position, and the chuck claw 14 is pushed down to perform the wedge action of the wedge mechanism described above. Then, the core bit 8 is crimped and fixed.

  The work before drilling is performed as described above, and after the work, the feed motor 9 and the rotation motor 34 are started. When the two motors 9 and 34 are activated, the core bit 8 is fed while rotating, and a cut into the concrete structure 2 is disclosed. At the start of cutting, the tip of the core bit is held in a fixed state by the chuck claws 14, so that the lower end of the core bit is not shaken.

  When the cutting is performed until the slide block 6 reaches the lower limit position, the feed motor 9 and the rotation motor 34 are once stopped. Then, the air cylinder 18 is controlled to pull up the chuck claws 14 to release the fixation by the pressure bonding to the core bit 8, and then the feed motor 9 is reversely rotated to pull up the slide block 6 along the support column to the upper limit position. During this time, the tip of the core bit 8 is maintained in a state of being cut into the concrete structure 2.

  When the slide block 6 is pulled up to the upper limit position along the support column 5, the chuck claws 14 are pushed down by the control of the air cylinder 18 and fixed to the core bit 8 by pressure. After fixing, the feed motor 9 and the rotary motor 34 are restarted to restart the cutting. When the cutting progresses and the slide block 6 reaches the lower limit position, the above procedure is repeated again to form a hole having a required depth.

  According to the core drill of the present embodiment, as described above, when drilling into the concrete structure grips the core bit 8 and makes a cut until it reaches the lower limit position, when the lower limit position is reached, the grip is released and the grip position is shifted upward. The length of the core bit 8 is selected according to the depth of the hole, which is performed by repeating the work of reopening the cut, but the tube may be replenished while the hole is being drilled.

  When the punching is completed, the feed motor 9 and the rotation motor 34 are stopped, but the fixing of the core bit 8 by the chuck claws 14 is maintained. Next, the feed motor 9 is rotated in the reverse direction, and the core bit 8 moves up. When the slide block 6 is pulled up to the upper limit position, the chuck claws 14 are pulled up by the air cylinder 18, and the fixation of the core bit 8 is once released. By the control of the air cylinder 18 that pulls up the chuck claws 14 and the control of the air cylinder 42, the pressing pads 41 on both sides of the core bit are respectively pushed inward in the radial direction, and the core bit 8 is sandwiched and held from both sides in the diameter direction. This prevents the core bit 8 from sliding down during drilling.

  With the core bit 8 held by the presser pad 41, the slide block 6 is lowered by the forward rotation of the feed motor 9, and the chuck claw 14 is lowered along the core bit 8 until the slide block 6 reaches the lower limit position. When the slide block 6 reaches the lower limit position, the chuck claw 14 is pushed down by the air cylinder 18 and the core bit 8 is fixed. After that, the above procedure is repeated, and the core bit 8 is pulled up from the hole and separated.

  When the slide block 6 reaches the upper limit position or the lower limit position, as described above, the chuck claw 14 is moved up and down by the control of the air cylinder 18 to be fixed to the core bit 8 or released therefrom. Monitoring is performed by manual operation, but if, for example, a limit switch or other sensor for detecting the upper and lower limit positions of the slide block is provided and sequence control is performed by the output from the sensor, the punching work is automated. , Can be operated remotely.

1・・Core drill 2・・Concrete structure 4・・Rack 5・・Post 6・・Slide block 7・・Head part 8・・Core bit 9・・Feeding motor 11・・Ring member 14, 28・・Chuck claw 14c , 17a...Tapered surface (wedge mechanism)
17, 29.. Orbiting members 18, 28, 42.. Air cylinder 19.. Piston 31.. Wire spring 34.. Rotating motor 41..

Claims (5)

  A support column having a rack attached thereto, a pinion reciprocally attached to the support column, which meshes with the rack, a slide block including a feed motor for rotationally driving the pinion, and a head unit integrated with the slide block. In a core drill including a core bit supported by the head portion in parallel with a support column and a rotary motor attached to the head portion and rotationally driving the core bit, the core bit is slidably fitted in the head portion, and Inside the head portion, a plurality of locations are arranged at appropriate intervals in the circumferential direction on the inner circumference around the core bit, and each of them can advance and retreat in at least the radial direction, the circumferential direction, and the core bit axial direction. At the same time, the chuck claws that can be orbited in the circumferential direction, and the chuck claws are pushed inward in the radial direction from positions radially separated from the core bit, and are crimped to the core bit to rotate the core bit, the feed direction, and the core bit shaft. Direction, and includes a pressing means that can release the pressing into the core bit and the rotation motor, and in a state where each chuck claw is pressure-bonded to the core bit, the rotation motor serves as a drive source to move the chuck claw into a circle. It has a revolving means for revolving in the circumferential direction, and a feeding means for feeding the chuck claws to the head portion in the axial direction of the core bit attached to the head part, with the chuck claws being pressed against the core bit. A core drill characterized by.   The chuck claw is movable in the axial direction of the core bit along the core bit, and the pushing means is attached to the head portion to move the chuck claw in the axial direction of the core bit, and the core bit around the core bit. 2. A wedge mechanism formed between the chuck claw and a revolving member that is disposed coaxially with the revolving means and revolves around a core bit using the feed motor of the revolving means as a drive source. The listed core drill.   The core drill according to claim 1 or 2, further comprising: a detaching unit that detaches the chuck claw from the core bit in a radial direction when the pushing by the pushing unit is released.   In the state in which the pressing tool that is arranged on the base side of the support column and that can move forward and backward in the radial direction and the pressing to the core bit by the chuck claws are released, the pressing tool is moved inward in the radial direction and press-holds the core bit. The core drill according to any one of claims 1 to 3, further comprising an actuator.   The chuck claw is pushed inward in the radial direction by the pushing means to be crimped to the tip side portion of the core bit, and while holding the tip side portion, the rotary motor and the feed motor are driven to feed the core bit while rotating the core bit. When cutting is started and the chuck claw reaches the lower limit position after the start of cutting, the pushing by the pushing means is once released, and then the feed motor is reversely rotated to retract the chuck claw along the core bit and retract to the upper limit position. After that, the chuck claw is crimped and fixed to the core bit by pushing by the pushing means, and then the core bit is rotated while being fed by the drive of the rotation motor and the feed motor to continue drilling, and the chuck claw reaches the lower limit position together with the core bit. Then, the pushing by the pushing means is released, and after the release, the procedure is repeated, and the drilling method using the core drill according to claim 1.