Improvements in Composite Pinions and Gear Wheels.
Year: 1890

page_text: COMPLETE SPECIFICATION.
Improvements in Composite Pinions and Gear Wheels.
We, JACOB CHESTER CHAMBERLAIN Electrical Engineer of 115 Broadway, and
WILLIAM LOUIS SILBEREISEN Confectioner of 1659 3rd Avenue, both of the City,
County and State of New York, in the United States of America, 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 :-
Our invention relates to improvements in composite pinions and gear wheels which
are composed of alternate layers or plates of metal or other hard material and raw-
hide or comparatively soft or non-resonant material, so that the harder parts take
most of the strain and wear while the softer parts serve as cushions, to render the
gear smooth and noiseless in action. The said pinion engages with an ordinary or all
metal gear wheel.
Heretofore the aforesaid layers or plates of which the composite pinion was made,
have been placed in planes at right angles to the rotative axis of the pinion. With
such a construction, the wear on the all metal gear wheel being confined almost wholly
to the parts opposite, and engaging with the metal layers of the composite pinion,
circumferential grooves were in time worn at those parts, leaving interposed ridges at
the parts opposite the raw hide.
The wear being thus confined to a portion only of the all metal wheel, the same is
more rapidly worn away and its working life is considerably shorter than would be the
case were the wear equally distributed. Furthermore, as the composite gear is in
practice a comparatively small pinion, it wears away much faster than the all metal
wheel and has to be replaced more frequently, and when a new composite pinion'is
put into engagement with an all metal wheel in which grooves have been worn as
above described, the grinding on both wheels due to this rough grooved surface is
very destructive, the more so as the plates of the new pinion will not in general
correspond or be in line with the grooves or ridges in the all metal wheel.
;;
The object of our invention is to distribute the wear equally over the working
faces of the all metal wheel, thereby lengthening the working life of the wheel and
maintaining it in a noiseless condition for a longer time, and also maintaining it in
condition to properly engage with a new pinion.
To accomplish this result we place the alternate layers of metal and raw hide of
which the pinion is composed, at a slight angle or cant to the axis of the wheel, so
that the metal portions, in bearing on the all metal wheel, travel laterally upon the
same by a worm like motion, so as to distribute the wear.
Another object of our invention is to prevent the raw hide plates of the pinion from
slipping when clamped between the metal plates.
Referring to the accompanying drawings, which form a part of this Specification:-
Figure 1 is a side elevation of a composite pinion constructed according to our
invention,
Figure 2 is a partial end view and
P

page_text: Figures 4 and 5 represent, by side elevation and section respectively, modified forms
of pinion constructed according to our invention.
Figure 6 is a diagram showing the wear on the all metal gear wheel.
The effect of wear on the all metal wheel by the action of the gear wheels as
heretofore made is clearly shown in Figure 6, in which various effects of wear are
shown, the differences being mainly due to differences in lateral play of the gear
wheels. Thus at b is represented the wear which takes place where there is a
minimum of such play, c where there is an average amount, and d where the gears
are quite loosely mounted so as to only leave slight ridges opposite the raw hide
portions, untouched by the metal plates. In these diagrams 11 represents the parts
that bear against the metal discs, and 12 the portions opposite the raw hide discs.
fin Figure 6 represents a peculiar wearing effect which takes place on a set of gears
exposed to the magnetic action of the motor. When the machine is working under
a heavy load, for example, at starting, the gear is attracted to one side, so as to
bring the metal portions of the composite pinion opposite the parts 13, and the wear
or grind being then very great, deep grooves are cut at these parts, but when the
motor is running freely it settles away into what may be considered the normal
position bringing the metal portions of the composite pinion opposite the parts 14,
upon which the wear will therefore be but slight.
The pinion shown in Figures 1, 2, and 3 is built up of rings or discs 1 of iron or
steel, or other metallic or hard material with interposed rings or discs 2 of raw-
hide or equivalent comparatively soft or non-resonant material such as vulcanized
fibre or wood.
These discs or rings have their centre holes 3 for the shaft, holes 4 for the clamping
bolts and their peripheral teeth 5, all bored or cut at a slight angle or inclination
from the perpendicular to the ends or plane faces of the discs, so that when the discs
are assembled, and clamped together by bolts 6, and secured on the shaft their planes
will be inclined to the axis of rotation. Suitably bevelled end plates 7 are provided
to square up the ends of the pinion, and the other plates are clamped between these
end plates by the aforesaid bolts.
As shown in Figure 1, the effect of the above construction is to cause the successive
teeth of a ring to be slightly displaced, in the direction of the axis, with reference
to one another, so that each tooth bears in part on a different portion of the engaging
wheel, from that engaged by the preceding tooth-thus shifting the wear and
distributing it over the whole working face of the all metal wheel.
To fully accomplish this result it is necessary to give a lateral displacement between
opposite diameters of the discs, equal to the thickness of the raw-hide discs. It is
also necessary that the number of teeth on the composite pinion should not be
exactly divisible into the number of teeth on the all metal wheel-and it is desirable
that the said numbers of teeth should be prime to, or incommensurable with, one
another, so that each tooth on the pinion shall be brought into engagement with each
tooth on the gear wheel.
To prevent the raw-hide discs from slipping when clamped between the metal discs,
the end faces of the latter are provided with projections 16, which enter the raw
hide. These projections are preferably struck up out of the surface of the discs, like
the teeth of a file.
In the construction shown in Figure 4, the rings 1 and 21 are split at one side as
at z and the ends pulled apart laterally a slight distance, and they are then assembled
together so that the end of each ring abuts against the opposite end of the next ring-
forming in effect two continuous helices, one of steel, the other of raw hide-running
side by side from one end to the other of the pinion. End plates of which one is
shown at 71 are provided and the whole series of plates or rings are clamped by bolts,
and the gear teeth cut in the periphery.
Substantially the same effect may be produced as shown in Figure 5 by making a
helical kerf or groove 8 in a solid wheel 9, and winding in such grooves a continuous
raw-hide band 10 so as to tightly fill the groove-the gear teeth being then cut across
the periphery. As it is not possible in this form to bind the raw hide
the
between

page_text: metal surfaces with sufficient tightness to stand the working strain, additional support
is furnished by small bolts 15 shown in dotted lines in Figure 2 passing through each
tooth of the composite pinion.
It will be seen that in the forms shown in Figures 4 and 5 the metal portions of
the composite wheel while bearing against the other wheel advance continually, by a
worm like motion from one end to the other of the wheel-while in the form shown
in Figures 1 to 3 the bearing point is merely shifted back and forth, through a slight
distance. The effect, as to distribution of wear is however the same, and broadly
speaking, the same means is used for producing it, namely, the displacement of the
teeth with regard to one another in the direction of the rotative axis, or the arrange-
ment of said teeth out of alignment with one another with reference to the plane of
rotation. Of course the above constructions could be applied to gear wheels in
general as well as the pinions.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
1. A composite pinion or gear wheel having toothed layers alternately of hard and
soft or non-resonant material, the teeth of each layer being out of alignment with one
another, with reference to the plane of rotation, for the purpose set forth.
2. A composite pinion or gear wheel having alternate layers of hard and soft or
non-resonant material, set at an inclination to the axis of rotation.
3. A composite pinion or gear wheel having toothed layers alternately of metal
and raw hide, or their equivalents-the-successive-teeth of each layer being-located=
successively in advance of one another in the direction of the axis of rotation.
4. The composite pinion or gear wheel composed of metal and raw-hide plates-with
centre hole for shaft and peripheral teeth cut obliquely to the plates, substantially as
and for the purposes described.
5. The composite pinion or gear wheel composed of metal plates 1, raw-hide plates 2
bevelled end plates 7 and clamping bolts, substantially as set forth.
Dated May
10.
J. C. CHAMBERLAIN.
WM. L. SILBEREISEN.
By Harris & Mills,
23, Southampton Buildings, London, Agents.