Improvements in Screw Wrenches.
Year: 1897

page_text: COMPLETE SPECIFICATION.
Improvements in Screw Wrenches.
I, JOHANNES SCHMIDT of Barmen, Allecstrasse 60, Germany, merchant, 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:-
This invention relates to improvements in screw wrenches, by means of which
it will be possible to adjust the head or the jaws with regard to its position to the
handle so as to be able to turn a bolt or a nut a few degrees only and then reset
the wrench for a new turning of same small angle again, instead of having to turn the
nut at least by 120° or more in order to be able to change the position of the wrench
on the hexagonal nut. It often happens that there is not sufficient room for the
handle of the wrench to be turned by 120° and resetting for a new partial turn is
then impossible. It also happens not seldom, that the width of the jaw of an
ordinary wrench is too wide to give a good hold on a nut and then it slips or turns
round the nut and the latter can not be tightened.
These draw backs of the ordinary screw wrench and also of the wrench with
adjustable jaws are avoided by my new improved wrench.
On the accompanying drawing
Fig. 1 is a view in plan of the same;
Fig. 2 is a side view,
Fig. 3 is a view similar to Fig. 1 partly in section,
Fig. 4 is a cross section of Fig. 1 along line I-I,
Fig. 5 shows an ordinary screw wrench with means for adjusting the width of the
jaw only,
Fig. 6 shows in three views the adjusting plate of the jaw.
In order to accomplish and attain the first object named above I make the head A
of the wrench movable on the handle B, that is, so that it can be turned on a
bolt C, holding both together; the upper part of the head forming the jaw D
may be forged or cast solid or it may be made of several plates or pieces rivetted
together; the rear or lower part is forked so that it can be slipped or stuck upon
the end of the handle, which preferably has a circular form. The two parts forming
the fork of the jaw head are provided at their circumference with notches E
standing radially to the bolt C and only so much appart from each other that
there may be left sufficient metal as is required to give sufficient strength.
The handle B is slotted in the middle, and in the slot F formed there is fitted
a sliding piece F1 of T shape, pressed upwards by a spring O and guided and held
in place laterally by covering plates H on both sides, which are rivetted together
with the slide F¹ and made rough at their outersides so that by their means this
sliding piece can be shifted backwards, out of the reach of the notches E, allowing
then to turn the head A. From this it will be understood how the head of the
screw wrench can be adjusted and reset to allow the turning of the nut or bolt
or of the handle respectively even in very small and narrow places.
The second object in view is to adjust the width of the jaw so that the new screw
wrench may serve within certain limits the purposes of an adjustable wrench.

page_text: I attain this object in a very simple manner by boring holes G through the sides of
the jaw and fitting into these the pins N of small filling plates J of various
thicknesses as indicated in Figs. 3 and 6 so that by their means the width of
the jaw can be reduced. The pins N are slit axially so as to act like a spring and
give a safer hold when put into the holes G.
These adjusting plates are kept ready for use with the screw wrench on its handle,
which is provided with the lateral holes K into which the pins N of the plates
are stuck, which are then held in place by a covering plate L connected to the
handle by a pin M, so that it may be turned to one side to allow the plates J to be
taken out of or replaced into the handle.
It is selfevident that these adjusting plates may be used with an ordinary screw
wrench M (Fig. 5), they are held thereon in the same manner as described and its
jaws are provided with holes G' in the same manner as described above and the
plates J are fixed therein in the same manner.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that
what I claim is:
(1.) In a screw wrench the combination of a movable forked head A with a
handle B, both joined together by a pin C, the rear circumference of the head
having notches E corresponding with a slot F in the handle; a T headed sliding
piece F in said slot held and guided therein by covering plates H and pressed
upwards into the notches E by a spring 0; the whole as set forth and for the
purpose specified.
(2.) In combination with a screw wrench as described in claim one holes G in the
sides of the jaw D and holes K in the broad side of the handle B, filling plates J of
various thickness having split-pins N to fit into the holes G and serving for reducing
the width of the jaw or to fix them to the handle, a covering plate L retaining them
in place at the handle when not used at the jaw.
(3.) In combination with the jaw of a screw wrench holes G₁ in the sides of the
jaw and filling plates J having split-pins N to be fitted into the sides of the jaw or
fixed alongside of the handle and held thereon by a covering plate L as described
and for the purpose set forth.
Dated this 4th day of June 1807
JOHANNES SCHMDT,
Per Karl J. Mayer, Agent.