Improvements in Screw Keys, Spanners, or Wrenches.
Year: 1896

page_text: Date of Application, 25th Nov., 1896
Complete Specification Left, 25th Aug., 1897-Accepted, 25th Sept., 1997
PROVISIONAL SPECIFICATION.
Improvements in Screw Keys, Spanners, or Wrenches.
I, JAMES MACEWAN Ross, of the Firm of R. G. Ross and Son, Engineers,
Greenhead Works, Glasgow, in the County of Lanark, do hereby declare the
nature of this Invention to be as follows:-
This Invention, which relates to screw keys, spanners or wrenches for use in
screwing up and unscrewing small or light bolts or nuts such as are common in
cycles and like machines, has for its object to provide for more readily adjusting
the gripping jaws of the spanners to fit varying sizes of bolts or nuts whilst dis-
pensing with the more expensive and troublesome screw spindle adjustment
commonly employed.
The improved screw key or spanner is composed of two jaw pieces each formed on
a stem piece or bar, the one, which may be termed the stationary jaw, having a
slot or orifice formed in it through which the stem of the movable jaw is passed
and is free to slide. The movable stem piece is oblong in cross section and tapered
on both sides towards its top and bottom edges, and the orifice in the stationary
jaw is similarly tapered or contracted towards its upper and lower ends, but is
of such larger size as will freely permit of the sliding through it of the movable
stem whose end may lie in a groove in the stem piece of the stationary jaw.
In using the spanner the jaw pieces are adjusted by sliding or telescoping the
stems on each other until the jaws exactly fit the bolt head or nut to be engaged.
The two stems are then gripped by hand and the pressure exerted on the gripping
faces of the jaws causes the tapered or beveled edges of the movable stem to grip
or lock with the tapered edges of the orifice in the stationary jaw and thereby
prevents the separating of the jaws. Upon relieving the pressure or ceasing to
turn the bolt or nut the movable stem piece will again freely slide in the orifice
of the stationary jaw.
1
1000
WALLACE FAIRWEATHER,
Of the Firm of Cruikshank & Fairweather,
Chartered Patent Agents,
ut Vincent Street, Glasgow, Agent for the Applicant.
Improvements in Screw Keys, Spanners, or wrencnes.
I, JAMES MACEWAN Ross, of the Firm of R. G. Ross and Son, Engineers,
Greenhead Works, Glasgow, in the County of Lanark, 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, which relates to screw keys, spanners or wrenches for use in

page_text: screwing up and unscrewing small or light bolts or nuts such as are common in
cycles and like machines, has for its object to provide for more readily adjusting
the gripping jaws of the spanners to fit varying sizes of bolts or nuts whilst dispensing
with the more expensive and troublesome screw spindle adjustment commonly
employed.
The Invention is illustrated by the accompanying drawings, Fig. 1 being a side
elevation, Fig. 2 a plan, Fig. 3 an end view and Fig. 4 a cross section on the
line Fig. 1 of the improved screw key or spanner.
The improved screw key or spanner is composed of two jaw pieces A, B, each
formed on a stem piece or bar A, B, respectively, the one A which may be termed
the stationary jaw, having a slot or orifice Aa formed in it through which the
stem B of the movable jaw B is passed and is free to slide. The movable stem
piece B is oblong in cross section and tapered on both sides towards its top and
bottom edges as shewn particularly at Fig. 4, and the orifice A2 in the stationary
jaw A is similarly tapered or contracted towards its upper and lower ends, but
is of such larger size as will freely permit of the sliding through it of the movable
stem B¹ whose end may lie in a groove A³ in the stem piece A¹ of the stationary
jaw A.
burnedd
In using the spanner the jaw pieces A, B, are adjusted by sliding or telescoping
the stems A, B1, on each other until the jaws exactly fit the bolt head or nut to be
engaged. The two stems A¹, B¹, are then gripped by hand and the pressure exerted
on the gripping faces of the jaws causes the tapered or beveled edges of the movable
stem B¹ to grip or lock with the tapered edges of the orifice A2 in the stationary
jaw A and thereby prevents the separating of the jaws. Upon relieving the
pressure or ceasing to turn the bolt or nut the movable stem piece B' will again
freely slide in the orifice A2 of the stationary jaw.
The jaws when closed may form a hammer and the ends of the stems opposite
to the jaws may be shaped to form useful tools such as a screw driver C and a tyre
remover D.
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:-
A screw key, spanner or wrench constructed and arranged to operate substantially
as described.