JP4669753B2 - Drilling device for step mounting hole in manhole - Google Patents

Description

  The present invention relates to a drilling device for a step mounting hole in a manhole for drilling a hole for attaching a step for raising and lowering a person to an inner wall of a manhole.

  In general, a step serving as a foothold for a person to move up and down is attached in the manhole. This step has a “U” shape, and is attached by embedding a part of two sides (both legs) of the open end of the “U” in concrete. This step can be installed by embedding the root in the concrete when manufacturing the manhole frame concrete, or can be installed after the frame concrete is manufactured.

  The present applicant possesses a technique for attaching a step using an impregnating adhesive after the manufacture of the frame concrete, and has been well received.

  Since the inside of the manhole is usually in an inferior atmosphere, the metal step causes corrosion or the like and needs to be repaired. In the case of this repair, it is necessary to process the step mounting hole and perform the step mounting work in the existing manhole.

  Conventionally, the step mounting hole has been drilled directly on the inner wall of the manhole and drilled with an electric drill, or a guide ring provided with a guide indicating the drilling position is attached to the inner surface of the manhole. A drill was drilled by hand using an electric drill. In this case, it is difficult to drill holes in parallel, and since holes are drilled one by one, there is a problem that it is not easy to drill holes with a precise dimensional interval with respect to the step dimensions. Moreover, the drilling work was very severe and the work efficiency was low.

  There is an improved apparatus for drilling a step mounting hole in such an existing manhole (see, for example, Patent Document 1).

This device attaches steps in a staggered arrangement in a manhole, and installs four drilling drills, two on the left and one on a frame, and operates two drills alternately on the left and right. Drilling holes. Therefore, the drilling position is eccentric with respect to the center of the frame, a large eccentric load is applied to the frame, and a large bending moment acts. Therefore, a robust frame is required. Moreover, since four drills are provided, the apparatus becomes large and expensive.
JP-A-4-216720 (page 2-3, FIG. 1)

  The steps in the manhole described above are attached by drilling the step mounting hole using a drilling hole in the manhole, including cases of new installation and repair. In this case, the step has a plurality of types of dimensions depending on the size of the manhole and the like, and it is necessary to drill a hole at an accurate position with respect to the distance between the legs of the step.

Conventionally, ascending / descending steps in the manhole are mounted in a staggered arrangement on the left and right one by one, and the ascending / descending step mounting hole drilling device corresponds to this, and is eccentric to the manhole diameter. A pair of drill holes were attached to the left and right of the center. The present invention is directed to a step arranged above and below a line in the manhole, the legs position of that, a simple accurate can drilling step mounting hole need not drilling apparatus little effort even in a narrow manhole The purpose is to provide.

  The present invention has been made to solve the above-described problems, and is a step drilling device in a manhole characterized by taking the following technical means.

That is, the present invention is a device for drilling mounting holes of symmetrical left and right U-shaped lifting steps arranged in a vertical line in a manhole, and is provided on the inner surface of the manhole at an arbitrary diameter position in the manhole. A center bar that is fixed horizontally by stretching both ends, a drill mounting frame that is attached to the center bar and is movable back and forth in the longitudinal direction of the center bar, and a longitudinal direction of the center bar on the drill mounting frame A drilling device for a step mounting hole in a manhole, comprising a drilling frame that includes a left and right drilling drill that is mounted in parallel and symmetrically with respect to the left and right.

In the present invention, the drill mounting frame includes a mounting portion for mounting one drilling drill on each of the left and right at the symmetrical position of the center bar, and matches the dimensions of both legs of the symmetrical step with respect to the center bar. Drill holes in the correct direction and position.

  The mechanism for advancing the drill mounting frame comprises a rack gear provided on the center bar, a pinion gear meshing with the rack gear, a ratchet mechanism provided on the pinion gear shaft, and a swing lever coupled to the ratchet mechanism. The use of this mechanism is preferable because it is easy to operate.

  In addition, if the hole drill is a hollow core drill with a diamond tip at the tip, and a device equipped with a water injection device that discharges water from the tip of the core drill, the hole can be drilled efficiently and accurately even if there is a reinforcing bar or the like. It is preferable that the hole is drilled and the position and size of the hole are not shifted.

Since the step hole drilling device in the manhole of the present invention is configured as described above, it is possible to easily and accurately drill the mounting holes of the lifting steps arranged in the upper and lower rows in the manhole . .

  Embodiments of the present invention will be described below with reference to the drawings.

  First, FIG. 6 shows a plan view of the step 27 to be installed in the manhole according to the present invention. In the present invention, the steps 27 are arranged in a vertical line in the manhole, and the shape thereof is a symmetrical U-shape. The impregnated adhesive is attached to both the leg portions 28 and pushed into the inner part of the step mounting hole of the manhole, thereby being firmly fixed in the manhole.

  A guide ring 24 conventionally used for step mounting hole drilling is illustrated in FIG. The guide ring 24 is a band-like expandable ring that is provided with a step mounting hole drilling guide 25. The ring 24 is reduced from the inner diameter of the manhole by the expansion / contraction device 26 and disposed at a required position in the manhole. The step mounting hole is drilled by a drilling drill guided by the positioned drilling guide 25. Even if this guide ring 24 was used, the drilling efficiency was not improved, and it was not sufficient for accurate drilling.

  FIG. 1 is a plan view showing a drilling device for a step hole in a manhole according to an embodiment of the present invention, showing a state where it is installed in a concrete manhole 1, and FIG. 2 is a side view of the drilling drill omitted. FIG. 3 is a side view in which a manhole is omitted and a drilling hole is described.

The hole drilling device of the present invention is used by pressing both ends of the center bar 2 to the inner surface of the manhole 1 and fixing the center bar 2 horizontally in the manhole in a stretched state. A drill mounting frame 3 is attached to the center bar 2 so as to be movable back and forth in the longitudinal direction of the bar. One drilling drill 4 on each of the left and right sides is attached to the drill mounting frame 3 in parallel to the longitudinal direction of the center bar 2 and symmetrically. The two step drills are simultaneously advanced to form step attachment holes in the inner surface of the manhole 1.

  The center bar 2 is a rod-like member that easily and firmly fixes the drilling device in the manhole 1, and is formed of, for example, hollow square steel in order to reduce the weight of the device. The center bar 2 includes an expansion / contraction mechanism that expands and contracts in the longitudinal direction. The telescopic mechanism presses both ends of the center bar 2 to the inner wall surface of the manhole. Therefore, the center bar 2 is stretched and fixed along an arbitrary diameter in the manhole 1.

  A screw mechanism is shown in the expansion / contraction mechanism of the center bar 2 shown in FIGS. A male thread 14 is formed on the outer diameter of the bar near one end of the center bar 2 (right end as viewed in FIG. 2), and a nut 15 is attached to the male thread 14. A rear reaction force receiver 16 is mounted via a coil spring 17. When the nut 15 is rotated, the rear reaction force receiver 16 follows the nut 15 and moves in the longitudinal direction, so that the center bar 2 can be adjusted to an arbitrary length.

  A front reaction force receiver 18 is joined to the other end of the center bar 2 (the left end as viewed in FIG. 2) by a bolt so as to be slightly rotatable. The portions where the front and rear reaction force receivers 16 and 18 are in contact with the manhole 1 are curved plates that match the curvature of the inner diameter of the manhole. Therefore, when the center bar 2 is fixed in the manhole 1, the center bar 2 does not damage the wall of the manhole 1.

  Although the embodiment shows a screw mechanism as the expansion and contraction mechanism of the center bar 2, other mechanisms such as a hydraulic mechanism can be used. The screw mechanism is the simplest and easy to handle.

  A hanging eye bolt 22 is attached to the upper surface of the center bar 2. A length scale 19 for determining the drilling length is provided on the upper surface.

  A gear box 10 is attached to the center bar 2. The gear box 10 covers the periphery of the center bar 2 and is externally fitted to the center bar 2. The drill mounting frame 3 is mounted on the upper surface and moves forward and backward along the longitudinal direction of the center bar 2. A pinion gear 11 is built in the gear box 10, and the pinion gear 11 meshes with a rack gear 9 provided on the lower surface of the center bar 2.

  The pinion shaft 12 of the pinion gear 11 passes through both sides of the gear box 10. One end thereof has a ratchet mechanism, and the lever 13 is engaged with the ratchet mechanism. By swinging the lever 13, the gear box 10 is moved forward and backward by the ratchet mechanism, and therefore the drill mounting frame 3 is moved forward and backward.

  The drill mounting frame 3 is a frame having a central portion coupled to the gear box 10 and a shape in which both wings are spread on both sides of the center bar 2. ing. On the upper surface of the drill mounting frame 3, a horizontal level 20 and a level 21 in the front-rear direction are provided.

  The drill mounting frame 3 is provided with hole drills 4 on both sides of the center bar 2 in parallel and symmetrically with respect to the center of the center bar 2, and the center distance between them is the center distance of the mounting part of the step. Equal to dimension. As shown in FIGS. 1 and 3, the hole drill 4 is firmly fixed to the drill mounting frame 3 by, for example, a large bolt 7 and a small bolt 7a.

  The drilling drill 4 according to the embodiment is an electric drill and is fed through a feeding cord 4a. Moreover, the water injection apparatus 5 supplied with water from the water supply hose 5a is provided, and the core drill 6 is mounted | worn as a drill. The core drill 6 includes a diamond tip 8 disposed in a ring shape at the tip, and is a drill of a type in which concrete is cut into a ring tube shape and a central core is extracted.

  FIG. 4 is a side view of the drilling drill 4 according to the embodiment, in which the water injection device 5 is partially cut away. In FIG. 4, the water entered from A passes through the core drill 6 and is discharged from B. 23 is a water seal. Water injection cools the diamond tip 8 at the tip of the core drill 6 while drilling a concrete manhole. By this water cooling, the diamond tip 8 is not burned out by frictional heat and can be operated more efficiently than a dry core drill. Further, as an advantage of the diamond tip 8, not only when drilling concrete, but also when hitting the reinforcing steel inside the concrete, the steel rod is cut without escaping like a general drill. Can be perforated.

  The method of using the device of the present invention is as follows.

  In a state where the nut 15 is turned to reduce the length of the center bar 2 from the inner diameter of the manhole 1, a rope is hung on the eyebolt 22 of the center bar 2 to lower the drilling device to a desired position in the manhole 1.

  The arrow 29 of the front reaction force receiver 18 and the desired position of the inner wall of the manhole are centered, and the nut 15 is turned to lightly press the rear reaction force receiver 16 against the inner wall of the manhole 1. Then, the leveling of the front, rear, left and right of the center bar 2 is adjusted by the levelers 20 and 21. Next, the nut 15 is turned to set the center bar 2 in the manhole 1 firmly.

  When the lever 13 is swung with the ratchet pawl (not shown) of the lever 13 in the forward direction, the drill mounting frame 3 moves forward toward the manhole wall.

  When the diamond tip 8 at the tip of the hole drill 4 comes into contact with the manhole wall, the scale of the length scale 19 is read to determine the hole length.

  Water is supplied to the water injection device 5 and the electric drill 4 is started while confirming water discharge from the core drill 6. When the predetermined drilling depth is reached, the lever 13 is swung with the ratchet pawl of the lever 13 in the retracting direction, and the drill mounting frame 3 is retracted to the original position.

  Water supply to the water injection device 5 is stopped and the electric drill 4 is stopped. The nut 15 is turned to loosen the tension of the center bar 2 and move to the next drilling position.

It is a top view of the drilling apparatus of the Example set to the manhole. In the side view of the embodiment of FIG. 1, a drilling hole is omitted. In the side view of the embodiment of FIG. 1, a drill bit is depicted. It is the side view of the drilling drill which showed a part of water injection apparatus in the cross section. It is a top view of the guide ring which provided the guide used conventionally. It is a top view which shows an example of a step.

Explanation of symbols

1 Concrete manhole 2 Center bar 3 Drill mounting frame 4 Electric drill (drilling drill)
4a Power supply cord 5 Water injection device 5a Water supply hose 6 Core drill 7 Large bolt 7a Small bolt 8 Diamond tip 9 Rack gear 10 Gear box 11 Pinion gear 12 Pinion shaft 13 Lever 14 Male screw 15 Nut 16 Rear reaction force receiver 17 Coil spring 18 Front Force receiver 19 Length scale 20 Leveling device in the left-right direction 21 Leveling device in the front-rear direction 22 Eye bolt 23 Water seal 24 Guide ring 25 Drilling guide 26 Expanding / contracting device 27 Step 28 Mounting part (both legs)
29 Arrow

Claims (3)

This is a device that drills mounting holes for symmetrical left and right U-shaped lifting steps arranged in a row in the manhole, extending horizontally on the inner surface of the manhole at an arbitrary diameter position in the manhole A center bar fixed to the center bar, a drill mounting frame attached to the center bar and movable forward and backward in the longitudinal direction of the center bar, and parallel to the longitudinal direction of the center bar and left and right to the drill mounting frame A drilling device for a step mounting hole in a manhole comprising a symmetrically mounted left and right drilling drill and a mechanism for advancing the drill mounting frame.   The mechanism for advancing the drill mounting frame includes a rack gear provided on the center bar, a pinion gear meshing with the rack gear, a ratchet mechanism provided on the pinion gear shaft, and a swing lever coupled to the ratchet mechanism. The drilling device for a step mounting hole in a manhole according to claim 1.   3. The drilling device for a step mounting hole in a manhole according to claim 1 or 2, wherein the drilling drill is a hollow core drill having a diamond tip at a tip thereof and a water injection device for discharging water from the tip of the core drill. .

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