Improvements in Gearing applicable to Measuring Tape Winders and Screw Propeller Shafts.
Year: 1894

page_text: Date of Application, 6th Nov., 1894
Complete Specification Left, 19th Jan., 1895-Accepted, 30th Mir., 1895
PROVISIONAL SPECIFICATION.
Improvements in Gearing applicable to Measuring Tape Winders
and Screw Propeller Shafts.
1, DAVID GAMBIA ERNEST DAVIES of 33, Cantlowes Road Camden Town in
the County of London Engineer do hereby declare the nature of this invention to
be as follows:-
The object of this invention is to provide a simple compact antifriction central
and self contained multiplying gear of great strength and durability for the rapid
winding of measuring tapes and (on a larger scale) for multiplying the speed of the
main driving shafts of marine engines in transmission of the motion to the screw
propeller.
My said apparatus comprises a fixed metal ring or cylinder which has internal
teeth and is fixed by any convenient method to a somewhat thin metal plate of
larger diameter than the latter in the centre thereof such plate being firmly
fixed 80 that it cannot revolve. In the centre of this plate a hole will be
made so as to allow of the insertion of a small toothed wheel or roller and
in between this wheel or roller and the outer fixed internally toothed ring or
cylinder is placed two or more intermediate toothed wheels or rollers equidistant
from one another and which fit in between the teeth of the outer internally
The inter-
toothed ring or cylinder and the centre toothed wheel or roller.
mediate wheels or rollers are driven round in between the outer internally toothed
ring or cylinder and the centre toothed wheel or roller by metal pegs or crank pins
which are placed loosely through their centre and will be fixed firmly by any
convenient method to another metal plate which is securely fastened to the main
driving shaft and will turn therewith. By this means these intermediate toothed
wheels or rollers get their rotary motion as they run along the teeth of the outer
fixed toothed ring or cylinder and transmit it to the centre toothed wheel or roller
as they partly follow the latter round, thereby causing it to turn several times to
one of the main driving shaft in advance and in the same direction as the latter
with but little friction such revolutions being proportional to the size of the wheels
and number of teeth respectively contained therein, thus enabling a long slow stroke
engine to be used and the steain economized.
Dated this 6th day of November 1894.
DAVID GAMBIA ERNEST DAVIES.
COMPLETE
SPECIFICATION.
Improvements in Gearing applicable to Measuring Tape Winders
and Screw Propeller Shafts.
1 DAVID GAMBIA ERNEST DAVIES of 33 Cantlowes Road Camden Town in
the County of London 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 :-
The object of this invention is to provide a simple compact antifriction central

page_text: and self contained multiplying gear of great strength and durability for the rapid
winding of measuring tapes and (on a larger scale) for multiplying the speed of the
main driving shafts of marine engines in transmission of the motion to the screw
propeller, but it may be used for other purposes without affecting the nature of this
invention.
My said apparatus comprises a fixed metal ring or cylinder A which has internal
teeth and is fixed by any convenient means to a metal plate B of larger diameter
than itself in the centre thereof, such plate being firmly fixed so that it cannot
revolve and of course will only serve as a means of preventing the internally toothed
ring or cylinder A from moving. The latter however may be held still by any
other convenient means which may from time to time and according to the purpose
for which the apparatus is applicable be found desirable. In the centre of this
internally toothed ring or cylinder A will be placed a small toothed wheel or roller D
and in between this wheel or roller and the fixed internally toothed ring or
cylinder A is placed two or more intermediate toothed wheels or rollers H¹
equidistant from one another and which must be of such diameter as to enable their
teeth to fit in between the teeth of the outer internally toothed ring or cylinder A
and the centre externally toothed wheel or roller D. The intermediate wheels or
rollers H are driven round in between the outer internally toothed ring or
cylinder A and the centre toothed wheel or roller D by metal pegs or crank
pins M which are placed loosely through their centre and will be fixed by any
convenient method to another metal plate G which will be securely fastened to the
main driving shaft E from where the apparatus receives its power and will turn
therewith. By this means the intermediate toothed wheels or rollers H' get their
rotary motion as they are driven along the teeth of the outer internally toothed
ring or cylinder A and transmit it to the centre toothed wheel or roller D as they
partly follow the latter round, thereby causing it to turn several times to one of the
main driving shaft in advance and in the same direction as the latter with but little
friction, such revolutions being consistent with the size of the wheels and number
of teeth respectively contained therein.
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 compact powerful and antifriction speed multiplying apparatus effected
by the construction of an outer fixed internally toothed rack, ring or cylinder
and by the driving of intermediate toothed wheels or rollers round in between such
rack, ring or cylinder and a centre movable toothed wheel or roller by means of
crank, pins or pegs connected indirectly to the main driving shaft through the
medium of a circular metal plate.
2. In the construction of a speed multiplying apparatus in which a fixed internally
toothed rack, ring or cylinder encircles the whole of the other wheels or rollers, the
centre roller being the point at which the power is delivered.
Dated this Nineteenth day of January 1895.
DAVID GAMBIA ERNEST DAVIES.