AN IMPROVED ADJUSTABLE SPANNER OR SCREW-WRENCH
Year: 1881

page_text: PROVISIONAL SPECIFICATION left by Gabriel Jacquemet at the Office of
the Commissioners of Patents on the 24th February 1881.
GABRIEL JACQUEMET, of Paris, in the Department of the Seine and Republic of
France. "AN IMPROVED ADJUSTABLE SPANNER OR SCREW-WRENCH."
The object of my Invention is a system of adjustable spanner or screw-wrench
affording at the same time great simplicity of construction with a strength not
hitherto obtained in this kind of tool, in which the regulation or adjustment of the
jaws have been operated by a screw, a nut, or their equivalent.
In fact in all these spanners it was the screw or the rod or stem which bore all
the strain, so that this screw or this rod soon twisted or got out of order.
In my system of spanner the adjustment of the jaws is obtained by means
of a variable number of small discs set upon a rod or stem which supports no
strain.
All the pressure is brought upon the pile or series of discs, which afford great
resistance because they bear against the heel of the fixed part or body of the
spanner.
I will now describe the construction of the apparatus and its working, reference
being had to the accompanying Sheet of Drawing.
A is the fixed jaw of the spanner, the stem or body B of which terminates by the
heel or shoulder C.
This stem B may extend beyond the heel so as to form handle for turning the
spanner more readily, or for this purpose a handle may be fitted on the heel or
shoulder C.
A jaw E is set on the stem B of the spanner so as to slide longitudinally.
F is a rod, the cross section of which is a circumference. On the upper half is a
lozenge, and the lower half passes through the pieces E and C.
Upon this rod are threaded the small rectangular plates G.
There is a spring at H.
The plates G are terminated by a semicircle on their side I, and form as it were
the teeth of a pinion of which H, bent at its lower end for this purpose, would be
the rack.
On pushing the rod F by its end J the spring is pressed and passes over the
desired number of plates, so that E rises.

page_text: If it is desired to stop the ascent of the spring and consequently of E, the
crank K is turned from right to left. The plates G which were passing in a
mortice L of E can no longer pass, being larger than the mortice in this direction.
The object of the lozenge shape given to part of the rod is to turn the plates; they
are loose on the rod B wherever it is round, and they are fixed on this rod when
the lozenge part passes through them.
It will be understood that by causing the suitable number of plates to pass, the
desired opening of the jaws of the spanner is obtained.
The total number of wedges and their thickness may vary with the limits of
opening of the spanner and the series of nuts which it is intended to operate
upon.
may vary the shape and dimensions of my spanners to suit different cases, and
use any suitable material for the construction of the various parts.
I have above described the application of my Invention to a spanner for operating
upon nuts, but I also claim its application to all kinds of spanners or screw-wrenches
for joints, pipes, and so on.
On the Drawing Figure 1 is an elevation of my spanner; the spring and
consequently the piece E may. move up and down; Figure 2 is a plan view;
Figure 3 an elevation. The plate M, N, O, P, Q, R, S, T, U, being removed, the
spring travels from E and is arrested by the discs; Figure 4 is a section at X, Y,
Fig. 3.