Improvements in or relating to Differential Gearing.
Year: 1899

page_text: Date of Application, 21st Aug., 1899-Accepted, 7th Oct., 1899
COMPLETE SPECIFICATION.
Improvements in or relating to Differential Gearing.
I, BIRGER ISIDOR RYDBERG, Engineer, of Westanfors, Kingdom of Sweden,
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 relates to differential gearings, which are principally charac-
terized by a wheel loosely mounted on the driving shaft and provided with
two either toothed or frictional rolling-paths, directed inwardly, opposite each
of which there is rigidly attached to the shaft mentioned a toothed or friction
wheel, which wheels are of different diameters, while on pins or the like on
the part to be driven there are loosely mounted wheels engaging with one of
the wheels fixed on the shaft and with the opposite toothed or frictional path
of the loose wheel; other wheels, moreover, loosely mounted on pins or the like
on a part which is stationary or fitted with a brake, being in engagement with
the other fixed wheel on the shaft and the other toothed or frictional path of
the loose wheel.
The invention is illustrated in the accompanying drawings as applied to a
rope-drum or the drum of a winch.
The drum a is provided with trunnions b and c intended to rest in corres-
ponding boxes on the frame. Said trunnions are made hollow in order to pro-
vide space for the driving-shaft d which carries three toothed or friction
wheels e, f, g, inside the drum. The wheels e and g are of different diameters
and keyed to the shaft d. Wheelf on the other hand runs loose on the shaft
and is provided with two inwardly directed either toothed or frictional paths.
The motion of the driving-shaft d is transmitted to wheel ƒ by means of the addi-
tional wheels h and i, of which the wheels h are loosely mounted on pins or studs
projecting from a flange on a bushing & passing with a loose fit between the
driving-shaft d and trunnion b, whilst the wheels i are loosely mounted on pins
or studs projecting from one of the end-walls of the drum. If the above-men-
tioned bushing k, either by means of a brake or in some other manner, he con-
nected with the frame and the driving-shaft & be set in motion, the drum a
will be compelled to take part in the rotation at a velocity which has a fixed
relation to the diameters of the wheels mentioned. For instance, if the wheel f
has 45 teeth, wheel e 13 teeth, and wheel g 15 teeth, then the driving-shaft d
must revolve about 30 turns in order that the drum shall revolve one turn.
The advantages gained by this invention are as follows:-
1: Ease of obtaining any ratio of gearing from a maximum to 1:100 or less,
if desired.
2: A power or transmission device of great strength with comparatively
small gear-wheels, because of the fact that several intermediate wheels h and i
may be employed, each acting on a separate pin or stud.
3: The gear as a whole occupies but small space.
4: All parts are well protected from dust. orit etc

page_text: 5: No open trains of gears or projecting parts are present which may form
a danger to the workmen.
6: The loss of power through friction is small.
Having now particularly described and ascertained the nature of the said in-
vention and in what manner the same is to be performed, I declare that what
I claim is:-
1. Differential gearing characterized by a wheel f loosely mounted on the
driving-shaft d and provided with two inwardly directed either toothed or fric-
tional paths opposite each of which is rigidly mounted on the said shaft a toothed
or friction wheel e g which wheels are of different diameters, there being loosely
mounted on pins or the like on the part to be driven wheels i in engagement
with one of the aforesaid wheels and the toothed or frictional path of the
wheel opposed, while other wheels h loosely mounted on pins or the like on
a part which is stationary or provided with a brake or the like are in engage-
ment with the other wheel e and the other toothed or frictional path of wheel f
substantially as described.
2. The arrangement of the differential gearing characterized in Claim 1 applied
to rope-drums or the like comprising the driving-shaft & passing loosely through
the drum a which encloses all the wheels and is provided with hollow trun-
nions bc and the pins or the like supporting the wheels i projecting inwardly
from one of the side-walls of the drum while the pins or the like supporting
the wheels h project inwardly from a part k loosely fitting around the shaft d
and reaching through the drum substantially as described or illustrated in
Figures 1 and 2 of the accompanying drawings.
Dated this 21st day of August 1899