IMPROVE- MENTS IN MOVEABLE SPANNERS OR SCREW WRENCHES
Year: 1867

page_text: PROVISIONAL SPECIFICATON left by Thomas Wilson at the Office of the
Commissioners of Patents, with his Petition, on the 20th June 1867.
I, THOMAS WILSON, of Birmingham, in the County of Warwick, Mechanical
Engineer, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN MOVEABLE SPANNERS OR SCREW WRENCHES," to be as follows:-
My Invention consists of the several improvements herein-after described
in actuating and adjusting the moveable jaws of spanners or screw wrenches,
and also in constructing the bodies and moveable jaws of spanners or screw
wrenches.
My said Invention consists, firstly, in actuating and adjusting the slide
bar or moveable jaw by means of a conical worm or screw attached to the
end of the handle of the spanner or screw wrench engaging with a rack or
screw teeth formed upon the edge of the slide bar or moveable jaw of the said
spanner or wrench. By giving a rotatory motion to the handle the slide bar
or moveable jaw may be made to approach to or recede from the fixed jaw.
My said Invention consists, further, in actuating and adjusting the slide
bar or moveable jaw of spanners or screw wrenches by means of a small

page_text: pinion engaging in the teeth of a rack upon the edge of the said slide bar or
moveable jaw, the said pinion being turned by a worm either formed upon
or attached to the inner end of the handle of the spanner or wrench. On
giving a rotatory motion to the handle its motion is transmitted through the
pinion and rack described to the slide bar or moveable jaw.
My said Invention consists, further, in actuating and adjusting the slide bar
or moveable jaw of spanners or screw wrenches by means of a worm formed
upon or attached to the end of the handle of the spanner or wrench, and
engaging in a rack or screw teeth formed upon the moveable bar or jaw, the
said moveable bar or jaw working in a line parallel with the axis of the
handle. By turning the handle motion is given through the worm and rack
described to the moveable bar or jaw.
My said Invention consists, further, in actuating and adjusting the slide
bar or moveable jaw by means of a screw on the end of the handle, the said
screw taking directly into a tapped hole or screw box in the back of the
slide bar or moveable jaw. The said moveable jaw is actuated by the motion
of the handle.
My said Invention consists, further, in adjusting and fixing the slide bar
or moveable jaw by means of, an excentric working in bearings in the slide
bar or moveable jaw or in the body or fixed jaw. The said excentric has a
'rack formed on its inner side, which rack engages with a corresponding rack
or screw teeth formed upon the slide bar or moveable jaw: The excentric
rack is operated by a handle or thumb plate attached to its end, which on
being raised disengages, the teeth of the excentric rack from those on the slide
bar or jaw and allows the said bar or jaw to be moved or adjusted to the
required distance. Instead of the thumb plate for raising or turning the
excentric rack the said excentric rack may be attached to the handle of the
spanner or wrench and raised or lowered thereby to adjust the slide bar or
moveable jaw. I also form the excentric rack so as to be capable of being
adjusted endways to, a slight extent in its bearings by means of a, screw bush
taking into one of the bearings and by which the slide bar or moveable jaw
can, be more nicely adjusted to its work. Instead of the screw bush described
the front jaw of the spanner or wrench may be made slightly moveable by the
screw by which it is attached to the body or fixed bar of the wrench, but I
prefer the first-described method of adjustment.
My said Invention consists, further, in forming the body or fixed bar of the
spanner or wrench forked, and making the slide bar or moveable jaw slide
between the said forked body or bar instead of sliding upon a single bar, as is

page_text: usual. I secure the fixed jaw to the forked body by pins or rivets passing
through both, and I actuate the moveable jaw by a screw working through
its back, the rear end of the said screw being attached to and sustained
by the body of the spanner and moved or rotated by a milled head also at its
rear end.