Improvements in Motors.
Year: 1894

page_text: Date of Application (in United Kingdom), 31st Aug., 1894
Complete Specification Left. 31st Aug., 1894-Accepted, 12th Jan., 1895
COMPLETE SPECIFICATION.
Improvements in Motors.
I, ANTONIO DELLA TORRE, of 405 Montgomery Street in the City and County
of San Francisco, in the State of California, one of the United States of America,
Mechanical Engineer, do hereby declare the nature of this invention and in what
inanner the same is to be performed, to be particularly described and ascertained
in and by the following statement :-
The invention has for its object improvements in gravity motors and aims to
produce and transmit both motion and power through the agency of rotating endless
screws driven by balls rolling in their thread.
Referring to the accompanying drawings for a detailed description of the said
improvements,
Figure 1 is a side elevation showing a motor provided with two sets of screws
and balls, made according to the principle of the invention. Fig. 2 is a top plan of
the same, the balls being removed.
Fig. 3 is a front elevation of a machine having but one set of screws, with
accompanying balls.
Fig. 4 is a side elevation, partly in section, of the machine represented at
Fig. 3.
Fig. 5 is a detailed view, on an enlarged scale, showing the preferred mode of
construction for the hub of the gear wheel in heavy machines.
The letter A represents the base of the machine, which consists of an iron band
or casting of circular form supported by screws a or any suitable standards adapted
to keep it a short distance above the ground.
Within the base A is a crown-wheel B rigidly secured to an upright shaft C
the lower end of which is pointed and fitted in a screw-step D that is held by
straps E bolted to bars F running across the foundation of the machine. The upper
end of the shaft is journaled and rotates in a hub G, which is held up by curved
arms H that project upwardly from the rim of the foundation. The hub and
spokes that bind the crown-wheel to the shalt may be of any suitable size and
strength, being light in small motors, as illustrated in Fig. 4, but much heavier or
reinforced in large machines, as indicated at Fig. 5.
IJ represent endless screws which are laid in sets of twos on an incline between
the hub G and the crown-wheel B, forming with them a right-angled triangle the
hypotenuse of which is to the vertical side as 100 to 55. These screws carry at
their lower ends pinions K L the teeth of which are adapted to engage those of the
gear-wheel B. They are held in place and adjusted by pointed screws M running
into the upper and lower ends of their stems respectively from the hub G and the
[D

page_text: base casting A. By turning the screws M and the step D, the crown-wheel and
pinions are thrown into gear, and both the endless screws will turn together, when
either one is rotated. The screws M are turned for adjustment by means of a
wrench. The screw-step is moved through the agency of bevel-gears N and a shaft
or rod O turned by a crank (not shown). The endless screws I J diverge in a
downward direction, running radially from the hub on the upper end of the vertical
shaft to the inner periphery of the circular foundation. The distance between them
varies from top to bottom in about the ratio of one to three. They are also of
different diameter and pitch, as shown, the thread or blade of the left screw in each
set being deeper and wrapped more closely around the stem than that of the right
screw, the blade of the left making three and one-quarter convolutions to that of the
right's three. The blades of the right screws in each pair are furthermore reversely
inclined and more slanting on the axis than those of the left screws.
The space
intervening between the right and left screws at the base is bridged over by a
trough shaped channel P, which is slightly inclined downwardly from left to right.
The intervening space at the top is taken up partly by a curved support or bridge Q
connected with the channel P by guide-bars R S running parallel with the screw-
stems. The guide-bar on the left is provided with a curved plate or leading board T
the outer edge of which runs close to the thread of the left screw.
The numbers 1, 2, 3 designate balls or spheres of equal size and weight that fit
more or less loosely in the spiral grooves formed by the screw-blades and are adapted
to travel therein, rolling down the left screw and up the right one, and from one to
the other across the connecting channel P and the bridge Q. On the left screw, the
balls bear upon the edge of the blade, where they acquire considerable purchase,
turning it as they roll down. They remain on the inner edge of this screw through-
out its length, being supported and kept from falling down by the guide R and the
plate T. On the right screw, the balls are borne more by the stem, along which
they roll up, guided by the bar S, so they have little or no leverage on the blade.
This is better illustrated on the right-hand side of Fig. 1. Provision is made for
the smooth and easy transition of the balls from one screw to the other by arranging
the blades so they will throw off the balls on a level with the inner surface of the
connecting channel at the base and curved support at the top. A Hat spring U is
set upon the stern of the screw I, below the guide R and plate T, in such a position
that the balls strike it when reaching the left end of the connecting channel and
receive an impulse from it at this point that speeds them on their journey toward
the base of the screw J.
The central vertical shaft C is used to transmit the power produced by the
gravitation of the balls, which may be applied in several ways, as may be found
most convenient. For instance, the power may be utilized to operate a pump V
through the medium of a shaft W connected at one end by bevel-gears X with
the upright shaft (and at the other end to the pump-rod by an eccentric Y, or it
may be used to run machinery by means of a pul ey Z and ordinary belting.
Any suitable form of governor may be employed to regulate the speed of the
n:otor. At the present time is used a fly which is operated by a train of gears c
from the outer end of a shaft d connected by bevel-gears e with the vertical
shaft C.
A brake of any suitable type (not shown) is used in connection with the shaft C
in order to stop the motor, when necessary.
The operation is as follows:
The balls are placed in the spiral grooves of the screws in about the position
illustrated in the left half of Fig. 1, balls Nos. 1 and 2 being set, with one turn of
the thread intervening between them, in the deep-grooved screw I, and ball No. 3
on the shallow-grooved screw J, at the lower end. In the deep-grooved screw,
the tendency is to roll the balls off the edge, but this is prevented by the guide
and leading board that run parallel with the screw-stem. The slope of the blade
of the shallow-grooved screw has the contrary effect and holds the ball close to
and above the screw-stem, aided partly by the guide-bar S. The brake, if used,

page_text: being then removed, balls Nos. 1 and 2 descend by gravitation and roll down the
edge of the left screw, thereby turning it and with it the crown-wheel through the
agency of the pinion K. The gear-wheel B, upon being set in motion, turns
the pinion L and consequently the right screw, which carries up ball No. 3, in
about the same manner that the other two are let down, except that the peculiar
twist or inclination of its thread does not allow the ball to bear much on the edge,
thereby reducing the effort to a large extent. The ball on the shallow-grooved
screw is also favoured in its ascent by the fact that it has a somewhat shorter
road to travel, the thread of the shallow-grooved screw making only three turns,
while that of the deep-grooved screw makes three and one-quarter turns. It is
thus made easier to preserve the relative distance between the ascending and
descending weights. Ball No. 1 having reached the lower end of the screw I and
passed clear of the plate T and guide R, it strikes the spring U and aided by its
recoil and the turning of the screw it is shot across the inclined channel P on to
the lower end of the screw J. In the meanwhile, ball No. 3 ascends to the summit
of the shallow-grooved screw, and the balls take about the position illustrated in
the right half of Fig. 1. As ball No. 1 reaches the lower end of the right screw
and becomes the ascending weight, ball No. 3 is rolled off the upper end thereof
across the bridge Q and unto the edge of the left screw, where it is transformed
into one of the descending spheres and lends its weight to ball No. 2 in order to
carry up ball No. 1. The machine will thus be set in motion and will continue to
operate until the brake is applied or the balls lose their relative positions. The
length of the endless screws, their relative distance at top and bottom, and their
respective pitch are such that there are always two of the balls running down the
left screw and carrying the third up the right screw, except when the lowermost
ball is gliding along the connecting channel and the highest is turning from ascent
to descent.
Experiment has shown that the machine can be actuated by the use of two balls
only, one in each screw, the excess of gravity in the deep-grooved screw being
sufficient to set the machine in motion, but not to create power.
The power is
produced by the third ball.
As many sets of screws may be used in each motor as may be found convenient,
but it is thought that four sets are all that will be needed for ordinary purposes.
The several series may be so arranged that the sets of balls will be moving up and
down at different times, if so desired.
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. A motor composed of a suitably mounted gear-wheel, endless screws carrying
pinions meshing into said wheel, connecting passages between the upper and lower
ends of said screws, and balls running into the grooves of each screw, down one
and up the other and from one to the other through said passages, the said balls
bearing upon the edge of one of the screws and upon the stem of the other,
substantially as set forth.
2. A motor consisting of a rotary vertical shaft having a horizontal gear at
one end, endless screws set on an incline between said shaft and gear, pinions fixed
upon the stems of said screws adapted to engage the horizontal gear, balls adapted
to travel in the screw-threads, an intermediate channel through which the balls are
transmitted from the lower end of one screw-thread to the lower end of the other,
and a corresponding passage or bridge at the upper end whereby the balls are
returned from the upper end of the second screw-thread to the upper end of the
first, substantially as set forth.
3. A motor consisting of an upright shaft carrying a gear-wheel, divergent
endless screws, pinions upon the stem of said screws engaging said gear-wheel and
causing them to rotate together, balls fitted to travel in the grooves or threads
of the screws, guides set parallel with the screw-stems whereby the balls are

page_text: retained in the grooves or threads, an inclined channel extending from the lower
end of one of the endless screws to the lower end of the other, and a spring
whereby the balls are ejected from one of the screw-threads into the inclined
channel, and thence to the other screw-thread, substantially as set forth.
4. A motor consisting of a rotary vertical shaft carrying a gear-wheel, inclined
endless screws radiating from a point near the shaft to the periphery of the gear-
wheel, balls adapted to roll in the grooves of said screws, guides whereby the balls
are kept from falling out of the grooves, connecting passages through which the
balls are delivered from one screw to the other, and one or more shafts connected
with the vertical shaft whereby power is transmitted from the motor, substantially
as set forth.
5. A motor consisting of an upright shaft carrying a horizontal gear, inclined
endless screws provided with pinions engaging the gear whereby they rotate in
unison, suitable passages connecting the upper and lower ends of the screw-threads
respectively, balls adapted to travel in said screw-threads and alternately move
down one and up the other, and an adjustable step mechanism in which the upright
shaft is supported whereby the latter may be raised or depressed to regulate the
engagement of the gear and pinions, substantially as set forth.
6. A motor consisting of a suitable base, a gear-wheel mounted therein, an
upright shaft rigidly secured to said wheel, an inclined deep-grooved endless screw
radiating from a point near said shaft to the rim of the base and adapted to turn
the wheel, a similarly-inclined and radiating shallow-grooved endless screw
adapted to be turned by the wheel, connecting passages between the grooves
of said screws, and balls alternately descending the deep-grooved screw and
ascending the shallow-grooved screw, substantially as set forth.
7. A motor consisting of a suitable foundation, a vertical shaft carrying a
horizontal gear mounted on the same, endless screws of different pitch set on
an incline between said shaft and base and both carrying pinions meshing into
the gear, connecting passages between the screws, and balls adapted to run
down the screw having the finer pitch and up the one having the coarser pitch,
substantially as set forth.
Dated this 31st day of August 1894
W. P. THOMPSON & BOULT,
Agents for the Applicant.