Improvements in and relating to Power Transmitting Mechanism for the Power Shafts of Electric and other High Speed Motors.
Year: 1895

page_text: Date of Application, 10th Sept., 1895-Accepted, 26th Oct., 1895
COMPLETE SPECIFICATION.
Improvements in and relating to Power Transmitting Mechanism
for the Power Shafts of Electric and other High Speed Motors.
I, DANIEL STEPHEN REGAN, a citizen of the United States of America.
residing at 708 Jones Street, in the City and County of San Francisco, and
State of California, one of the United States of America, Mechanical 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 present invention relates to an improved mechanism for transmitting the
power developed in the armature-shaft of electric motors and other high speed
prime movers, and the invention has for its object the adaptation of a new and
improved form of reduction gearing for use in this connection. To accomplish
this object I employ certain mechanical elements which will cause a maximum
variation of speed between the first and last elements of the mechanism with a
minimum throw of the eccentric, such an operation being very essential, as the
moving gears must be balanced concentrically with the shaft in a line central with
the eccentric and directly opposite its highest point. And the invention therefore
consists in the construction, arrangement, and combination of parts, substantially
as will be herein after described and claimed.
In the annexed drawings illustrating my invention―
Figure 1 is a transverse sectional view of my improved power transmitting
device.
Figure 2 is a face view of the gearing, viewed in the direction of the arrow
shown in Figure 1, and with one of the discs removed.
Figure 3 is a view similar to Figure 1, showing the apparatus arranged in
connection with the armature shaft of an electric motor.
Like letters of reference denote like parts in all the different figures of
drawings.
A denotes a shaft which is adapted for rotation by any suitable kind of motor.
In the present example it is shown in Figure 3 as the armature shaft of an electric
motor, but it may be any other high speed shaft. G denotes the electric motor.
On this shaft A are two discs B and C, of any desired size and form. These discs
are provided at their onter peripheries with circular flanges B and C, which
preferably come into contact with each other as shown, said flanges constituting
together a closed compartment, both of which flanges are supported revolvably
upon the shaft A, from which as a prime-mover, motion may be imparted to either
one of the discs, the other being held stationary by any suitable means. The
flange B of the disc B is internally toothed at b, to provide an internal gear
wheel, and the disc C is provided at a suitable point from the flange C¹ with a
concentric flange C2 which is externally toothed to provide a gear wheel c.
Keyed on the shaft A between the discs and C is an eccentric D having the
minimum size possible to achieve a given result, and loosely supported on this
eccentric is a combined external and internal gear wheel, the outer edge of which
is a spur gear wheel E, whose periphery is concentric with the periphery of the
eccentric and whose diameter is such as that a portion of its teeth will be in mesh
with the teeth 6 of the internally-geared disc B, its number of teeth being less than
those of gear b. I preferably provide the external spur gear E with ninety-two
teeth and the internal gear 6 with ninety six teeth. These numbers are given,
however, merely as examples, and I do not wish to be restricted to them.
Thus

page_text: when the shaft A rotates the gear wheel E will have a compound movement, since
it will not only rotate on its own axis, but it will also revolve around the axis of
shaft A, with its teeth entering consecutively the teeth 6 of the internal gear.
The wheel is provided near its toothed periphery, with a flange E', which is
internally toothed at e, said teeth being in mesh with the gear wheel c, which, as
we have seen, is integral with the disc C. A similar relationship exists between
the internal gear e and the external spur gear c, as obtains between the gear
wheel E and the internal gear b, in that they are eccentric to each other, and the
internal gear e has a compound movement, the other gear c having in this instance
the smaller diameter and the less number of teeth. For example, the gear e may
have sixty-four teeth and the gear c sixty teeth, but of course I am not restricted
to these numbers. The gear wheel E has a less number of teeth than the internal
gear and consequently will revolve more rapidly than the disc B, the speed of
the latter being reduced proportionately to the difference in size of the two wheels,
in accordance with the well known principle of reduction gearing. Similarly the
dise C will have a faster rate of movement than the gear wheel E, since its gear
wheel c is of less diameter and of a less number of teeth than the internal
with which it is in mesh. Therefore, if the disc B be held stationary by suitable
devices, as for instance, by clamp H, shown in Figure 3, the movement of the
disc C will be diminished below that of the rapidly moving actuating shaft A, and
vice versa; if the disc C be held stationary, the revolution of the disc B will be
retarded below that of the shaft A and the amount of the reduction in each case
will be dependent on the relative size of the different gears, and hence by regulating
their size, proportions and arrangement, any desired reduction can be had. The
direction of motion of disc B when disc C is held stationary is opposite to that of
dise C when dise B is held stationary.
gear e
It will thus be seen that the principal gear wheel in my combination is the
combined external and internal gear wheel, which is one having an external gear
and also an internal gear, and one which is loosely supported upon an eccentric,
and that its external gear meshes into the teeth of an internal gear wheel of larger
diameter, while its internal gear meshes into the teeth of an external gear of less
diameter. It is an absolute novelty in reduction gearing, having the same purpose
in view as that sought to be achieved by my combination, to provide an internal
gear wheel supported loosely upon and driven by an eccentric with which it is
concentric and engaging a spur wheel of less diameter. This conspicuous feature
which characterizes the combined external and internal gear wheel, is of extreme
importance in my combination, for thereby I am enabled to obtain with a small
eccentric, one having a slight throw, a reduction equivalent to that ordinarily
gained in ordinary reduction gearing with a much larger eccentric. I lay particular
stress upon this improved result and the markel advantages accruing therefrom.
The difference in diameter between the external gear E and the internal gear e
will vary as much as desired in different devices, according to the nature of the
result to be attained in the use of the same.
On the drive-shaft AI place a balance or balance-wheel F, which is securely
fixed on the shaft. It may be located within the discs B and C, or at any other
point on the shaft, the exact point being a matter to be ascertained in practice.
This balance is of great importance in making the movement of the gearing steady
and uniform and avoiding irregularities and jerks, which strain and damage the
machinery, and it is indispensable when the gearing is employed with high-speed
prime-movers, such as electric motors. Heretofore it has not been practical to
employ gearing of this kind with rapidly moving shafts because of the shaking and
jarring of the parts due to the high speed, but by balancing the mechanism as I
have done, the use of the gearing becomes practicable, and it may be utilized in
many ways and for many purposes.
Various changes in the precise construction, arrangement and relative proportion,
and the like, of the different parts may be made without departing from the
invention.

page_text: 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. The combination with a driving shaft and an eccentric fixed thereon and
revolving therewith, of a combined external and internal gear wheel, revolving
loosely upon and driven by the eccentric, and the internal and external gear wheels
respectively engaging said external and internal gear.
2. The combination with an electric motor and its driving shaft, of an eccentric
fixed thereon and revolving therewith, a combined external and internal gear wheel
revolving loosely upon and driven by the eccentric, and internal and external gear
wheels respectively engaging said external and internal gear, substantially as
described.
3. The combination with a driving shaft and an eccentric fixed thereon and
revolving therewith, of a combined external and internal gear wheel revolving
loosely upon and driven by the eccentric, the internal and external gear wheels
respectively engaging said external and internal gear, and a balance on the shaft
for counterbalancing the eccentric and the gearing supported thereon, substantially
as described.
4. The combination of a driving shaft, an eccentric fixed thereon and revolving
therewith, a combined external and internal gear wheel revolving loosely upon and
driven by the eccentric, an internal gear on the shaft engaging the aforesaid
external gear and having a greater diameter and a greater number of teeth, and an
external gear likewise on the shaft and engaging the internal gear of the combined
gear wheel and having a less number of teeth than the internal gear, together with
a balance on the shaft for counterbalancing the eccentric and the gearing supported
on the eccentric, substantially as described.
Dated this 10th day of September 1895
JENSEN & SON,
77 Chancery Lane, London, W.C., Patent Agents.