PROVEMENTS IN RATCHET BRACES
Year: 1876

page_text: PROVISIONAL SPECIFICATION left by William Spour at the Office of the
Commissioners of Patents on the 16th March 1876.
"IM-
WILLIAM SPOUR, of Walker-upon-Tyne, in the County of Northumberland.
PROVEMENTS IN RATCHET BRACES."
This Invention consists chiefly in an arrangement of ratchet brace that will cause
the tool to go twice the number of revolutions in a given time that the ordinary
brace will drive it, and in a brace that will travel both during the forward and the
backward stroke of the handle.
1st. On the barrel or body of the ratchet brace, in which the main screw works
at one end, and into which the tool is stuck at the other end, I construct two mitre
wheels facing each other. The upper one of these (nearest the screw) is free to
revolve, the other is fast. Gearing into these I place a preferably equal and similar
mitro wheel. This contral mitre wheel is made to run on an axis at right angles to
the body of the brace. This axis consists of a bar, usually cylindrical in shape,
and called a stop bar. It has an eye at one end encircling the body of the ratchet
brace. The other end of the bar projects out so that it can rest against a stationary
support, usually the drill stand. A collar on the bar keeps the mitre wheel in
position. The handle is also attached to the body by an eye or eyes, or usually one
on each side of the eye of the stop bar. On the handle are are catches or pawls
working on the ratchet mitre wheels, one in one direction, the other in the other.
There can if desired be four pawls, two to each wheel, so arranged that only one
can be in action at a time on each wheel. The operator can then arrange to make
the tool turn either way. If desirable only one pawl, and that on the upper wheel,
can be put in action. The ratchet brace will now be changed into a single-acting
one, with this great advantage, however, that the drill goes through double the
angular distance that the handle passes through in the same time, instead of through
an equal distance, as in ordinary machines. When a hole is drilled, it can be
tapped by putting the tap in the brace and driving it down by the brace screw,
this brace having this advantage over all others that by putting the back pawl
or pawls into action instead of the ordinary one, the drill can be withdrawn by the
brace.
2nd. I sometimes vary the arrangement by putting the intermediate wheel on the
handle. The stop bar can then be of any convenient shape, and has a pair of
catches on its upper side gearing into the upper wheel only. This form is a little

page_text: cheaper and simpler than the last, but is only single acting. It however has the
valuable quality of doubling the speed of the tool, and can be made to go either
way, and tap holes.
3rd. I have not gone into the details of construction, as these are common to all
ratchet braces in many respects; nor is there any remarkable point about my
machine as to details except these: 1st, there is a collar or boss on the body of the
brace round the tool socket, upon which the bottom mitre wheel works. The body
is then parallel, but has a nut or collar at the top, either screwed on and held by a
pin or set screws, or fixed in other safe and substantial manner, so as to keep the
upper mitre wheel in place.