US86837A - Improvement in saw-g-atjge - Google Patents

Description

To all whom tt ma/y concern utd tant A. HOFFMANN, OF PHILADELPHIA, PENNSYLVANIA.`

Laim Param No. 86,837, dated Fenna/ry 9, 1869.

INTROVEMENT IN SAW-GAUGE.

The Schedule referred to in these Letters Patent' and making part of the lame.

Be it known that I, A. n. HOFFMANN, of Philadelphia, Pennsylvania, have invented a Gauge for Determining the Length of the Clearing-Teeth of Cross-Gut Saws; and I do hereby declare the following to be a full, clear, and exact description of thesame.

My invention consists of a gauge, constructed and adapted to the teeth of a saw, substantially as described hereafter, and serving as a guide in rapidly and accu'- rately reducing the length of the clearing-teeth in respect to those of the cutting-teeth.

In order to enable others skilled in the art to make and use my invention, l will now proceed to describe the mode of constructing and using the same, reference being had to the accompanying drawing, which forms a part of this specification, and in Which- Figure 1 is a perspective View, showing my improved gauge as it appears when applied to.a cross-cut saw;

Figure 2, a transverse section of the same; and

i Figure 3, a longitudinal section.

On reference to the drawing, X represents a portion of a cross-out saw, shown in red lines, which is provided with teeth y, having two cutting-points, and clearing-teeth z, arranged alternately, as shown.

It is impoitant that these clearing-teeth z should be somewhat shorter than the cutting-teeth, so that they may not interfere with the proper functions of' the latter; and it is also important that the clearingteeth, although shortened, should be o'an equal length throughout, the attaining of which object requires tedious manipulation, when the points are filed down, as

heretofore, without the aid of any other guide than the" eye of the operator.4

The gauge consists of a plate, A, bent to the form shown in iig. 1, and cut away at the bend, so as'to present an opening, a, through which the point of the clearing-tooth shall project when the gauge is passed over the saw-blade, and the inner edge t' of its ends b b rests upon the points ofthe cutting-teeth y, as shown in the drawing.

The edges n of the opening a are at a distance below the points of the cutting-teeth, as indicated by parallel red lines c d, fig. 3, and the point of the clearing-tooth, prior to being filed, projects above these edges.

All that is necessary, after adjusting the gauge, is to reduce this projecting point, by means of a i'lle, until the latter is arrested by the edges n of the opening a of the hardened steel gauge, these edges determining the length of the clean'ng-tooth in respect to that of the cutting-teeth. v

Thus, tooth after tooth can be correctly and rapidly reduced by any unskilled operator, whose oniyremaining duty is to file the bevelled edges of the clearingteeth, so as to sharpen the same, after being made blunt by filing the points. y

I am aware that a folded plate adapted to the edge of a saw, and carrying guides which direct the sharpening-tools, has been used, but it Will be seen that the above-desciibed plate, instead of being a holder for guides, is a gaugeitself, and is for a d iiferent purpose than the device alluded to, this purpose-the determining of the length of clearer-teeth-being accomplished by the peculiar arrangement of the edges a and t'.

I claim as my invention, and desire to secure by Letters Patent- A gauge, consisting of a folded plate, A, having a recess, a, in the centre, the edges n of which are arranged, in respect to the edges 4', of the folded portion of the plate, as and for the purpose described.

In testimony whereof, I have signed vmy name to this specification, in the presence of two subscribing witnesses.

A. E. HOFFMANN.

Witnesses:

C. B. Pinon, HARRY Sm'rH.

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