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United States Patent Office EDWARD S. STEHMAN, OF LANCASTER, PENNSYLVANIA. BLOCK FOR ENGRAVERS' USE. SPECIFICATION forming part of Letters Patent No. 348,299,
dated August 31, 1886. Application filed January 25, 1886. Serial No. 180,591. (No model.) To
all whom it may concern:
Be
it known that I, EDWARD S. STEHMAN, of Lancaster, in the State
of Pennsylvania, have invented certain new and useful Improvements
in Blocks for Engravers' Use, whereof the following is a specification,
reference being had to the accompanying drawings, in which—
Figure
1 represents a central vertical section through the apparatus;
Fig. 2, a similar section on a plane at right angles to that
of Fig. 1. Fig. 3 is a view of one of the holding-pins to
be used in connection with the block. Fig. 4 is a view of
the under side of the flat clamping-plate, which is upon the
top of the block. Fig. 5 is a top or plan view of the block
as it appears when said clamping-piece (shown in Fig. 4) is
removed. Fig. 6 is a top or plan view when the jaws (which
in Fig. 5 are marked L L) are removed, and Fig. 7 is a horizontal
section on the line x x of Fig. 1.
My
invention is intended to provide an engraver's block which
has, among others, the following advantages over those now
in use: It revolves upon a true vertical axis without appreciable
friction, and in revolving has no projections from the main
surface which are liable to catch in surrounding objects,
it is adjustable at any height, and it is capable of holding
objects of any shape, however irregular, either by lateral
or downward pressure.
In
the drawings, A represents a solid base piece, in the center
of which is a vertical hole adapted to receive a stout cylindrical
pin, D, which fits snugly, but so as to move freely, within
said hole, and which may be adjusted and secured by means
of set-screws C at any desired height. The pin D terminates
in a sharp-pointed cone, around whose base is a circumferential
groove, as shown in Figs. 1 and 2. The bottom piece, B, of
the revolving block is provided with a central vertical hole,
terminating conically, which coincides with the upper surface
and end of the pin D. A slot, G, shaped like an inverted T,
extends diametrically across the block B, and said block is
also formed with an offset extending around its upper portion,
so that when the cap M, which fits over the entire top thereof,
is place in position the vertical sides of said cap shall
be flush with the main surface of the block. Said cap M has
a transverse slot, e, extending nearly across its upper surface
and coinciding with the top of the slot G. Within said T-shaped
slot G are two correspondingly-shaped nuts, a a, threaded
to engage with the right and left screw E, which extends entirely
across the block and through the sides of the cap M. Said
screw has a detachable key, F, by which it can be turned in
either direction. The tops of the nuts a a are just flush
with the upper surface of the cap M, and of course can simultaneously
be caused to approach the center of the block or retraced
therefrom by turning the screw E in one or the other direction.
A pair of semicircular jaws, H H, are secured to the tops
of the nuts a a by means of screws h h, which are formed with
shoulders adjacent to the threaded part, so as to permit each
of said jaws to turn freely upon the shank of its fastening
screw as a pivot, the screw-holes in the jaws being also countersunk,
so that the tops of said screws are flush with the top surface
thereof. Referring now to Fig. 5 it will be seen that each
of said jaws is perforated with a series of vertical holes,
N, arranged symmetrically and as close together as the strength
of the material will permit, which said holes receive the
holding-pins P, which should be formed, as shown in Fig. 3,
with shoulders r and heads s of inverted conical form.
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