Improvements in Wrenches and Holding Tools, applicable also to Cramps and the like.
Year: 1891

page_text: Date of Application, 10th Mar., 1891
Complete Specification Left, 7th Dec., 1891-Accepted, 9th Jan., 1892
PROVISIONAL SPECIFICATION.
Improvements in Wrenches and Holding Tools, applicable also to
Cramps and the like.
We, ERNEST GUSTAV HOFFMANN of 5 Clarendon Villas, Beaconsfield Road,
New Southgate, Engineer, and EDWARD ROBOTHAM of 36 Sackville Street
London W. Gentleman, both in the County of Middlesex, do hereby declare the
nature of this invention to be as follows :-
:-
Our invention relates to improvements in wrenches for applying and loosening
screw nuts, it being applicable also to holding tools and to cramps and the like.
We will explain our invention by describing it in its application to a wrench.
The wrench has the usual fixed jaw and handle. the loose jaw being adapted to
slide to and fro from the fixed jaw as usual, but said jaw is rendered adjustable and
capable of being held in the desired position by means of a spring carried by same
and by a pair of links which embrace the body of the wrench and connect with
said loose jaw and with a sliding piece which preferably works in a groove in the
back of the body of the wrench, the sides of said groove being cut at such an angle
that the sliding piece which has a tongue engaging with same will wedge in it and
be prevented from moving in a backward direction so that the jaw will be held up
to the object it is holding. Instead of the groove the back may if desired be
toothed and the sliding piece carry or act as a pawl to engage therewith, or in
place of the sliding piece and groove an eccentric may be carried by the links,
which eccentric will bear and tighten upon the back of the body of the wrench to
prevent the loose jaw moving in a backward direction. The eccentric would in
this case be provided with a spring or means for keeping its engaging or larger
portion from tight contact with the back of the body of the wrench when it is
desired to slide the loose jaw up and down. We preferably form the various parts
so that they may be stamped from sheet metal for the purpose of economy and
convenience.
In applying our invention to a cramp either the loose or fixed jaw would carry a
set screw or the like to hold it after being tightened up.
Dated this 10th day of March 1801
PHILIP M. JUSTICE,
55 & 56, Chancery Lane, London, Agent for the Applicants.
COMPLETE SPECIFICATION.
Improvements in Wrenches and Holding Tools, applicable also to
Cramps and the like.
We, ERNEST GUSTAV HOFFMANN of 5 Clarendon Villas, Beaconsfield Road,
New Southgate, Engineer, and EDWARD ROBOTHAM of 36 Sackville Street,
London, W., Gentleman, both in the County of Middlesex, do hereby declare the
nature of this invention and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement :-
Our invention relates to improvements in wrenches for applying and loosening
screw nuts, it being applicable also to holding tools, such as cramps and the like.
To clearly explain the nature of our invention reference is made to the accom-
panying drawing in which :-
Fig. 1 is a side elevation of our improved wrench with a part broken away.

page_text: Fig. 4 is a side elevation of our invention as applied to a cramp.
Fig. 5 is a rear view of same.
The tool is provided with the usual fixed jaw a, and movable jaw b, the latter
sliding upon the shank C, the back of which may be flat, or be preferably formed
with a groove d.
In this grooved slides a block e, the edge of which may be wedge shaped as
shown in Fig. 2, to engage with the groove. This block e has a link g pivoted to
it on either side, the other end of said link being pivoted to the movable jaw b, the
pivot point of the latter being lower than the pivot on the block, so that the latter
is higher up the shank c than the former.
с
To keep the block e and movable jaw close to the shank and temporarily hold
them in the position in which they are placed, we place a small piece of spring
wire in a circular groove in the movable jaw, one end being turned down as
shewn to engage with a hole formed to receive it, while the other end is turned up
to engage with a hole formed in one of the links g. The effect of the spring is to
keep the block e through the links y pressed slightly into the groove. The spring h
is not quite long enough to fill the circular groove in which it rests, there being
room for some compression to take place.
When lowering the movable jaw the gripping block e may be taken hold of and
loosened from the groove, slightly compressing the spring, and the block and jaw
may then be slid down the shank. To raise the jaw it is preferable to take hold of
same and push it upward. The tool will hold firmly upon any nut or the like
placed between the jaws by reason of the pressure upon the movable jaw being
transferred by the links to the block e which will wedge in the grooved and be
held firmly at the point on the shank at which it is placed.
In Figs. 4 and 5 our invention is shewn as applied to a cramp, the arrangement
being identical with that above described though the tool is provided with the
usual adjusting screw i by which the necessary pressure is exerted on the movable
jaw.
We preferably form the various parts so that they may be stamped from sheet
metal for the purpose of economy and convenience.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that
what we claim is :-
1. In a wrench or holding tool a movable jaw connected by a link or links to a
gripping block sliding on the shank, substantially as described.
2. In a wrench or holding tool a shank having a grooved back, a movable jaw
connected by links to a block sliding in said grooved back, and means for keeping
the movable jaw and block upon the shank, substantially as described.
3. The improvements in wrenches and holding tools substantially as described
and illustrated.
Dated this 7th day of December 1891.
PHILIP M. JUSTICE,
55 & 56, Chancery Lane, London, Agent for the Applicants.