An Improvement in Hand Ratchet Braces.
Year: 1890

page_text: Date of Application, 14th July, 1890
Complete Specification Loft, 14th App, 1901 Accepted, 16th May, 4:01
PROVISIONAL SPECIFICATION.
An Improvement in Hand Ratchet Braces.
ETHELBERT THOMAS RUTHVEN-MURRAY Sunnyside Banbury Road Oxford
Civil Engineer do hereby declare the nature of this invention to be as follows:-
This invention relates to improvements in hand ratchet braces, whereby the
necessary pressure is obtained without the use of a spanner or lever to extend the
screw. In this invention the pressure is obtained by forcing the screw out by means
of a nut, this nut, which is just above the ratchet, being of larger diameter and
having teeth on the lower side which gear into teeth at right angles cut on the end
of the lever handle, so that to obtain pressure the pulling lever is merely twisted
& so by means of the nut the screw is driven out.
Dated this Fourteenth day of July 1890.
ETHELBERT THOMAS RUTHVEN-MURRAY.
COMPLETE SPECIFICATION.
An Improvement in Hand Ratchet Braces.
I, ETHELBERT THOMAS RUTHVEN-MURRAY of Sunnyside, Banbury Road,
Oxford, Civil Engineer, 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:-
My invention relates to improvements in hand ratchet braces whereby the necessary
pressure for drilling is obtained without the use of a spanner or other lever to
extend the screw. In my invention the pressure is obtained by forcing the screw
out by means of a nut situated just above the ratchet wheel which is geared to
teeth on the end of the pulling lever.
The arrangement will be seen by the accompanying drawings.
Fig. 1 is a side elevation.
Fig. 2 is a plan.
Fig. 3 is a section on Y Z.
There is a fork A, and handle or pulling lever F as in an ordinary ratchet
brace.
Between the two branches of the fork are situated the ratchet wheel B, and
pawls C, C¹.
The lower end of the ratchet wheel forms the chuck, and has a seating for holding
the drill as shewn in the drawings.
Directly above the ratchet wheel I place a nut D, which is tapped to receive the
square threaded screw E. This nut is preferably in two portions D. D' rigidly
fastened together by a key. D is of larger diameter than the ratchet wheel and
has teeth cut on the lower projecting face. D' is an annular portion having a centre
at its lower end which communicates the pressure from the centre at the top of the
screw E. to the chuck B and so to the drill. The pulling lever F passes through a
bearing in the fork casting and carries at its extremity a pinion F' which gears
with the teeth on the nut D. The screw E is slotted its whole length and a feather
ca-t on the fork A prevents it turning and makes it partake of the reciprocating
motion given to the handle while drilling.
When it is desired to increase the pressure on the drill the pulling lever is given
a turn and this motion is communicated by the pinion F¹ to the nut D, which since
the screw E cannot revolve, communicates pressure to the chuck B through the
Price 6d 1

page_text: centre on D¹. In the forward or cutting stroke all the parts partake of the same
motion, but in the backward or idle stroke, the chuck and ratchet wheel B are held
by the friction of the drill and the remainder, the fork, nut, screw, and handle turn
on the internal centre in B. In order to take up any wear on this centre there is a
screw collar G which allows for adjustment. The whole mechanism is enclosed by a
steel guard H which is divided at one end so as to form springs for the pawls. One
or more of the screws which hold this guard also prevent the collar G from working
slack. My object in having two pawls is that by making one half a tooth longer
than the other, they gear alternately, and reduce the back lash or waste motion
without reducing the size of the ratchet teeth.
The drawings shew a very compact brace suitable for use in confined situations.
The only difference in the construction of a long brace is that the portion of the
chuck B projecting below the fork is lengthened, the portion D' of the nut carrying
the centre is lengthened, and the screw E is also lengthened.
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. The pinion F1 on the end of the pulling lever.
2. The bevil wheel nut and centre D. D¹.
3. The arrangement of the parts to enable the pressure on the drill to be increased
by means of the pulling lever substantially as described and shewn on the accom-
panying drawings.
Dated this 11th dow of AA D 1001
ETHELBERT T. RUTHVEN-MURRAY.