US1607310A - Cutting tool - Google Patents

Description

Nov. 16,1926. 1,607,310

J. F. ROSS CUTTING TOOL Filed Feb. 11. '1924 dingy/1 1 1K 066 53 MM. C/QWAUQWM flifiawau gfl Patented Nov. 1%, i926.

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JOSEPH F. ROSS, OF IPSWICH, MASSACHUSETTS.

CUTTING TOOL.

Application filed February 11, 1924. Serial No. 691,935.

This invention provides an improved cutting tool. More particularly it relates to a f tool for use in concrete construction for removing the ends of the embedded mold- 5 wires, cutting them below the surface of the surrounding concrete.

In the making of concrete walls it is customary to construct a mold of boards between which the concrete is to be poured, these boards being held on uprights and kept at the proper distance apart by wires which run through the mold from one side to the other, tying the two sides of the mold together. The concrete having been poured and hardened, the taking down of the mold leaves projecting ends of the wires which must be removed to an appreciable depth below the surface, in order that no rust stains may appear. The present practice is to chip away the surface concrete around the wire until the latter can be cut with a cold-chisel an inch or more below the face of the wall. This retults in the removal of considerable concrete leaving a saucer-shaped cavity which mustbe filled promptly in order to make a bond with the nearly tempered wall. Such patches are generally noticeable, are liable to become loose, and in many cases undergo crumbling around the edges, to the disfigurement of the wall. The time required to chip away the concrete, chisel 03 the wirc, and then patch the place makes this necessary work a substantial item of expense.

The present invention provides a tool for cutting such projecting wires below the surface with removal of but little concrete. It

is an object of the invention to provide for the doing of this quickly and cheaply, as re-.

gards labor costs; neatly, as regards preventing disfigurement of the face of the wall; and also easily, at sufficient depth,-as regards operative effort required.

These ends are attained by providing a combined concrete-boring and Wire-cutting bit. It is one feature that the bit is selfguided, and its operation automatically concentrated, by the wire which is to be cut. It is another thatthe hole which it makes in the concrete is of only the size predetermined by the bit, for example, about one-half inch or so diameter, which hole is'made precisely where needed. It is another feature that the cutting function is divided and separated into two parts of the same tool, one of which, for cutting the wire, is carried and protected by the concrete cutter while reaching its operating depth; and that both cut ters may be of suitable material and temper each for its special purpose. It-is still afurther feature that the concrete borer and the metal cutter are operated by the same bit-stock or brace, which may be one of ordinary type, held and operated comfortably by the workman. I

The bit combines a head having axial hole and eccentric boring point with a toothed wire cutter close behind the head. There is also on the bit a clamping device for setting the cutter in cutting position against the wire. This device is far enough behind the cutter to be accessible for operation by the workman while the head and the cutter are beneath the surface of the concrete. In the specific form here illustrated the-cutter is a tool-steel lever, constituting approximately half of the cylindrical bit, the division being along the axis. This semicylindrical lever is pivoted to the shaft of the bit near the shank and is so shaped that its cutting end, which is cloie behind the head of the bit, has a small but sufiicient swing toward and from the other half, which is rigid with the head and the shank, and is herein called the shaft; and means is provided for the operator to set it firmly toward this shaft.

At the said axis the hole extending through the head into the cleft between the two halves of the bit, is large enough to receive the wire or a pair of wires which are to be cut. hole and with the cutter lever slightly open, the bitpoint can be worked into the concrete, being held steady with concentrated effect by the wire around which it rotates. At proper depth the lever can be set toward the axis, setting its cutter firmly against the wire close behind the head and setting the wire-against an anvil there on the shaft. Further rotation of the tool cuts the Wire.

The invention may be applied in various forms. one of which is illustrated. It is intended that the patent shall cover, by suitable expression in the appended claims, whatever features of patentable novelty exist in the invention disclosed.

In the accompanying drawings:

.VVith the Wires threaded into this Figure 1 is a side elevation of a emcircle cut by the head of the bit. Preferably bodying the invention;

Fig. 2 is a plan of the same;

Fig. 3 is an end view of the same; and

F 4 and 5 are sections on lines 41 and respectively, of Fig. 1.

eferring to the drawings, indicates the shank which in this case has a square taper suitable for cngagen'ient in an ordinary bit-stock or brace. The shaft 11 0f the tool is approximately semi-cylindrical and is rigid with the shank 10 and witlrthe full round head 12. The latter has a cylindrical hole 13 at its axis; carries eccentrically a forward projecting horn 14 constituting a concrete boring point; and is formed with a spiral groove 15 for escape of the concrete crumblings. There is also a surface longitudinal groove 15 in the shaft, for escape of dust.

Alongside the semi-cylindrical shaft 11 is a semi-cylindrical jaw lever 16 pivoted thereon at 17 near the shank, so that its free end or jaw 16, close behind the head 12, may have a little movement toward and from the axis. For this a thumb-screw 18 penetrates the lever 16 and threads into the shaft cutting teeth like those of a file.

11. The jaw end of the lever 16 has an edge 20 turned in toward the axis, suitablyshaped and tempered to form a cutter for wire lying in the hole 13 at the axis. I have found that a V-shaped notch with toothed or serrated edges 20, as seen in Fig. 4, provides a suitable cutter. The teeth may preferably be A light spring 22 about the stem of the thumb-screw 18 tends to keep this jaw open, so that its position at any time is determined by the setting of the thumb-screw 18.

The wire is held securely in position, to be engaged by the cutter, by the head hole 13,

and y a pair of lugs 23 upstanding1 from the shaft 11 close behind the jaw. T e bottom 24 of the recess between the head 12 and y the lugs 23 constitutes a sort of anvil for supporting the wire against the pressure of the cutter. The opposed surfaces of the shaft 11, and the lever 16, may diverge from each other outward from the axis, to provide sufficient clearance for-escape of any of the concrete crumblings that may lodge between them, so that the cutter can always be pressed against the wire.

In operation, one backs off the thumbvscrew so that the jaw springs open far enough for the wire that; is to be out to be threaded through the hole 13 across the anvil 24, thence between the lugs 23, into the cleft between the shaft and the lever. The wire tobe cut thus serves as a fixed guide for the tool as a Whole and acts as a pivot for centering and steadying the cutter when the tool is rotated. The lever should be set close enough to the axissothat its leading end does not have a largergadius than the the back of the forward semicircular end of the jaw should be beveled as at 27, so that if the jaw happens not to be set in enough, its contact with the wall of the hole being bored will automatically move it in. One then rotates the bit, which is assumed to be held in an ordinary bit stock, with forward pressure, in which case the rather blunt point of the horn 14 has all of the workmans pressure concentrated conveniently at its point, andcrumbles the concrete around the wire until the Wire cutter 20 has entered to the desired depth. The best time for this operation is 48 to 72 hours after the pouring of the concrete, before it has'become set too hard for easy removal by this method. One then, by means of the thumb-screw, sets the cutter against the wire and continues his rotation of the bit. As the wire is soft this quickly cuts the wire sufficiently for its breakage to occur. Upon removal of the bit a small neat round hole is left in the concrete into the bottom of which the stub of wire protrudes. This may be bent out of the axis of the hole, and the hole then filled with concrete. The stub of wire serves as a key or dowel for holding thisconcrete plug perma nently in place. The exposed surface of concrete patch is small; the edges are strong: and the whole job is thus finisher] in a neat and satisfactory manner, quickly and at slight expense.

In the tool thus constituted it will be understood that the horn-shaped eccentric boring point 14 works upon the somewhat fresh or green concrete with an abrasive action which is concentrated within the desired area because the bit rotates on the protruding stub of wire as on a pivot. This point does not nec essarily protrude so far as is illustrated in the drawing; and if its protrusion be less the hole need not be bored so deep in order to effect the cutting of wires at any predetermined distance below the surface of the concrete. In any event if the cutting be too near the surface, the wire can be bent or jammed back into the deeper part of the hole. In general it is preferred to have the cutter close behind the boring head, or at least located at the head in such manner that it is associated with it. This being beneath the surface of concrete, the shaft 11 and the lever 16 constitute stems which reach into the hole, one carrying the anvil and the other the cutter, and these are for conven ience referred to as stems in the claims which follow.

I claim as my invention:

1. A cutting tool adapted for concrete boring, comprising a shaft adapted to be rotated upon its axis and having a boring point set eccentrically and protruding in the direction of the axis beyond all other parts of the tool, combined with a wire cutter havthey follow into the hole made by the point."

2. A cutting tool comprising, in combination. a shaft having a head adapted to bore concrete: a cutter-for wire at the head;

and means for setting the cutter against the wire, located at a part; of the tool which is outside of the concrete when-the cutter is within it. i

3. cutting tool comprising a concrete borer having an axial hole for receiving wire that is to be cut, and a wire cutter mounted on the tool in 'position to act on the wire received in said hole.

4. A cutting tool comprising a borer for concrete and a wire cutter adapted to enter and to operate in the hole made by the borer while the latter remains in said hole.

cutting tool for cutting wire beneath the surface of concrete, comprising a boring head, an anvil for wire behind theboring head, and a cutter adapted to act on the wire at said anvil; there being stems, one for the said anvil and one for the said cutter, adapted to occupy simultaneously the holemade by the borer.

ii. A cutting tool for cutting wire beneath the surface of concrete, comprising a boring head, an anvil for wire behind the boring head, and a cutter adapted to act on the wire at said anvil; there being stems, one for the said 'amiland one for the said cutter, one of which. also serves for said head, adapted to occupy simultane ously the cylindrical hole made by the borer;

and means outside of the concrete to clamp the two stems together thereby thrusting the cutter toward the anvil to cut the wire.

7. A cutting tool comprising a stem with v boring head, having an axial hole for wire 8. A-cutting tool comprising a stem with boring head, having an axial hole for wire that is to he cut, ci.ni'ibined with a stem pivoted on the firststorm-parallel to it with possibility of slight motion toward and from it within its cylinder of rotation; and a wire cutter on the secondstem atthehead of the first stem; and means to set'the two stems together to cut wire,

9. A tool for cntting'wirebeneath the surface of concrete, con'iprisi'ng, a boring head for the concrete about the wire; and a cutter adapted to cut the wire in said hole back of said head, whereby upon removal of the tool a portion of the wire is left protruding into the hole madeby the. said head.

10. A'cutting vtool comprising a concrete borer; and means toengage wire in the hole made thereby; said means being adapted by rotary motion to sever the wire.

11. A rotary concrete cutter combined with a rotary wire cutter, the latter being set close behind the'cutting point of the concrete cutter and beingadapted to operate at the axisflof the said concrete cutter.

12. The combination with a wire cutter, ota bit having a rotary boring-point which extends eccentricallyforward of the cutter suid bit being adapted to remove material around a wire, and said cutter being 'adapted to cut the said wire within the space left by the said removed material.

13. A rotary concrete cutter comprising. a bit'having a boring point projectingforward eccentrically; there being anaxial hole adapted. to receive'a wire embedded in and projecting from the concrete, which wire may constitute a pivot about which the bor ing point travels when rotated.

14. A rotary concretecntter comprising a bit having a'n'axial hole adapted to rereivea tixed guide projecting into it, such as a wire embedded in the concrete and projet-ting therefrom, which guide -may consritutc a pivot '-steady,ing the cutter in its rotation, said cutter having meansv arranged eccentrically for wearing away the concrete.

- 15. A cutting tool comprising aboring hit having a cutter. for wire, adapted to embrace the wire from opposite sides. and by rotation to cut the wire, both borer and cutter being adapted to beat the same time in the hole made by the bit.

16. A cutting tool comprising a bit having a cutter for wire, adapted to embrace the wire from opposite sides and by rotation to cut the wire, both borer and cutter being adapted to be at the same time in the hole made by the bit, there. being a V for n element constituting a part of said means for embracing the wire.

17. A cutting tool comprising a bit, hav-' ing acntter for wire, adapted to embrace the wire' from opposite sides and by rotationto cut the wire, both borer andcutter being adapted'to be atthe sametime in the hole made by the bit, there being a hard metal t'ootlr forming a part of said embracing means and adapted to cut into the wire when the bit is rotated.

18. A rotaryconcrete cutter comprising a bit having at its rear end an axial shank for rotating the. cutter and having at itsforward end a boring point projecting forward ecoentrically, an abrasive edge extend ing thence rearward, and an axial hole adapted to receive' av wire; said point be.- ing in advance ofthe remainder of the bit and adapted to cut a circular groove in theconcrete. when rotated; and the said til) rearward extending abrasive edge being adapted to crumble concrete between the groove thus cut and the said wire.

19. A rotary concrete cutter comprising a bit having a boring point projecting forward eccentrically, an abrasive edge extending from the pointrcarward along and toward the axis, and having an axial hole; said point being in advance of theremainder of the bit and adapted to cut a 10 circular groove in the concrete when rotated; and the said abrasive edge having back of it an inclined-surface coacting with said edge to remove concrete circumscribed by the said groove. 15

Signed at Boston, Massachusetts, this thirteenth day of January, 1924..

JOSEPH F. ROSS.

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