Screw-wrench or Spanner.
Year: 1893

page_text: Date of Application, 11th Aug., 1893
Complete Specification Left, 11th May, 1894-Accepted, 16th June, 1894
Screw-wrench or Spanner.
CHARLES HENRY WYNN Century Works Commercial Street Birmingham
Manufacturer do hereby declare the nature of this invention to be as follows:-
A screw-wrench or spanner with a loose screwed thumb-bit arranged with a
spring & steel balls so as to pull out of gear and when released spring back into
gear with screw rack on bar of spanner.
4
By this method, when the thumb-bit is pulled out of gear the jaw slides freely
& down, and when in gear it (the jaw) can be adjusted exactly by the
up
screw.
:
1, CHARLES HENRY WYNN of Century Works, Commercial Street, Birmingham,
Manufacturer, 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 pertains to constructional improvements in that type of screw
wrench or spanner in which the movement of the movable or sliding jaw is
produced by the rotation of a worm or screw roller mounted thereon and working
upon a corresponding screw rack provided upon one of the sides of the spanner
lever arm; and my improvements consist specifically in the manner in which I
mount the worm or screw roller, upon the movable jaw; so that it may be readily
disengaged to permit of such movable jaw being speedily slipped over the surface
of the teeth of the rack, to suit the size of the bolt head or nut which it is desired
to operate upon while at the same time the worm or screw roller may be released
to engage with the teeth for tightening or easing the grip of the sliding jaw.
In order that my invention may be the more clearly understood, I append
hereunto a sheet of explanatory drawings in which Figures 1 and 2 represent
elevation and plan respectively of a spanner shewing the manner in which I carry
my invention into effect: while Figures 3 and 4 represent detail sections of the
sliding jaw, shewing the worm or screw roller in engagement and disengagement,
respectively, with the teeth of the rack.
In carrying my invention into effect as illustrated in various figures of the
drawing--I make the main arm or lever portion A of the spanner from metal,
having a solid head or shank B formed at its extremity-and at the opposite end,
I provide a suitable handle for manipulation. I form upon the underside of the
arm a series of teeth or serrations a a preferably of a flat surface-to suit the worm
or screw roller C which I mount in the movable jaw D. for working thereon. I
likewise make the sliding jaw D. of metal, and preferably of a box-like sectional
configuration for passing freely over and working upon the arm or lever A ; and
upon the underside thereof, I provide a suitable gap or recess of a sufficient depth
to receive the worm C for engaging with the teeth of the rack. I make the worm C
with a convenient number of convolutions either of square or other shaped threads
to suit the teeth of the rack. I drill out the centre of the worm to form a cylinder,
LD
037

page_text: for the reception of two hardened metal balls E E! with a spiral spring F or other
resilient element disposed between, for forcing or tending to force the balls apart :
and I provide upon either side of this gap or jaw a suitable inclined recess e e¹ of
circular configuration at its lower end to partly receive the ends of the balls so
forced apart by the spring: which recesses I slightly incline towards the surface
at the top of the sides as is clearly seen in the sectional views of Figures 3 & 4; so
that in disengaging the worm C from contact with the teeth a a the balls E E' are
brought together in traversing the inclined recesses e e¹ against the resistance of
the spiral spring F-and on release again the worm C immediately resumes its
normal engaged. position.
By such an improved construction I am enabled to provide a spanner which is
at once simple and easy of manipulation-and in which the cost of production is
almost a minimum.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. In a spanner or screw wrench the construction of a movable or sliding jaw,
having a hollow cylindrical worm or screw roller arranged within a gap or recess
formed thereon in such manner as to be capable of ready engagement or
disengagement with the teeth of the screw rack formed upon the lever arm, upon
which it works; by the means of two metal balls with a spring interposed, arranged
within the said worm, each ball working within a suitable inclined recess formed
upon the side of the gap; the worm or screw roller being thereby normally, forced
into engagement with the teeth of the rack substantially as hereinbefore described.
2. The construction of a spanner substantially as hereinbefore described and
illustrated.
TL 1
MARKS & CLERK,
18, Southampton Buildings, London, W.C., Agents.