US90195A - richard - Google Patents

Description

tait-rd gime @sind @Mira Letters Patent No. 90,195, dated May 18, 1869.

IMPRovmmNT IN H'oLLow AUGER The Schedule referred to in these Letten Patent and making part of the lame,

To all lwhom. it may concern.-

Be it known that I, H. J. Bronnen, oi' the city oi' Rochester, in the State of New York, have invented a new and useful Hollow 'Ienoning-Bit; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawing, making part of this specification, in which- Figure 1 is side elevation,'with a portion of the head a: cut away, to show' the arrangement of screws h and pins y.

Figure 2 is an inverted view of the face of cutterheads.

The nature of this invention consists in arranging the several parts composing the expansive cutterheads, in the manner hereinafter described.

To enable others skilled in the art to make and use my invention, I will describe its construction and operation.

The shank of this auger is made as others ot' this class, and 'can be used in a carpenters brace.

The head a: is provided with a groove in its edges to receive transversely-moving arms a.

These arms have T-shaped heads, b, which have on their inner edges circular recesses, which, when the heads are together, form an opening as large as the smallest tenon required.

rlhe face of the T-heads is slightly convex, so that the knives will make their cut as other hollow bits.

A cavity is formed in the face of each T, to receive the cutter-knives j, tig. 2.

This cavity is inclined from the centre of the head to the outside, so that the knives will be in an inclined position as to the face, so that the cutting-edge will be presented to the wood.

The knives are attached to theheads by the screws g passing through counter-sunk slots, iig. 2.

At the cutting-edge of the knives f, proper throats are provided in the T-heads, to allow for the passage of chips.

These knives f may be insertedv in slots in the edge of the T-heads.

The arms a are held in the grooves of the heads by means of the right-and-left screws h, iig. 1, and are operated thereby.

These screws hare formed by passing a rod through the head, and making on its ends a right-and-le'l thread. f

In the centre, ya. groove is cut, and a pin, w, is put through the head, and passes through the groove, and allows the rod to turn, but prevent-s end movement. I also, in rear ofthe screw h, insert and fix rigidly guidepins y, which serve to sustain the arms.

In the edge of the ends of theT-heads, I make a square groove, and lit therein a sustaining-bar, p, lig.

1, one end of which is rigidly fastened .to eachT by a screw, and the other end has a slotted hole in it, throilrgh which a clamping-screw, x2, is inserted into the @By this arrangement, when the arms are set at the desired distance apart by the screw h, the sustainingbars p are fastened by the clamping-screws :and'snstain the heads of the arms a in position.

On one or both .arms a graduated scale or a movable set may be made to indicate the length ofthe tenon.

The object of this invention is to make an adjustable hollow tenen-bit, so that small as well as large tenons may be cut with the same.

Another object is, lthis hollow bit can be used with 'l any common boxing-bit, whereas, with the common hollow auger, it is necessary to have the boring-bit made to t.

This is accomplished in this auger by having the knives adjustable, that being done by turning .the screw h, which will cause them to approach or recede, as desired, and ,make a tenon to {it any-sized boringbit. Two screws may be put in the bars p, to hold the tenon while being out;

What I claim as my invention, and desire to secure by Letters Patent, is

1. The head a, screws h, in combination with the movable T-headed arms a, all being constructed and arranged to operate substantially as and for the purpose set forth.

2. In combination with the above, the sustainingbars p and clamping-screws x2, as and for the purpose set forth.`

)ELl J. RIOKARD. Witnesses:

Jas. LonENzo GAGE, J. Cruise.

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