Improved Driving Gear for Locomotive Engines.
Year: 1893

page_text: COMPLETE SPECIFICATION.
Improved Driving Gear for Locomotive Engines.
I DAVID SHAW PATTERSON of Box 26 Post Office, North Platte, in the County
of Lincoln, and State of Nebraska, United States of America, Inventor, 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 invention relates to a new and simple driving gear for locomotive engines
designed to prevent horizontal straining of the axle journals, and pounding of the
wheels on the rails whether caused by the centrifugal force of a single main
connecting rod, a single parallel rod, or a single crank pin, or by the angular thrust
of the main connecting rod.
The invention consists of a front and a rear cylinder arranged on opposite sides
of the driving wheel, and connected by their connecting rod with crank pins located
on opposite sides of the centre of the driving wheel.
Reference is to be had to the accompanying drawings forming a part of this
Specification, in which similar letters of reference indicate corresponding parts in all
the figures.
Figure 1 is a side elevation of the improvement as applied on a locomotive having
double driving wheels. Figure 2 is a plan view of the same. Figure 3 is a like
view of the improvement as applied on a locomotive having single driving wheels.
Figure 4 is an enlarged sectional plan view of the driving wheel on the line 4-4 of
Figure 5; and Figure 5 is a sectional rear view of the same on the line 5-5 of
Figure 4.
As
The improved driving gear is provided with the two engine cylinders A and B
having the usual pistons and cross heads connected by their connecting rods C and D
respectively with wrist pins E and F respectively arranged at opposite sides of the
centre of the driving wheel G as plainly shown in the drawings. Each of these
cylinders will only be about half the usual size. The wrist pin E is preferably
formed at its outer end with a crank arm H extending diametrically on the face of
the driving wheel G and carrying at its outer end the outwardly-extending
wrist-pin F connected with the other connecting rod D as above mentioned.
shown in Figures 4 and 5, the wrist-pin E is formed or secured at its inner end on
a block E¹ preferably made triangular in shape and fitted into a correspondingly
shaped aperture G₁ formed in the web of the driving wheel G. Set-screws I
screwing half into the web of the wheel G and half into the block E¹ serve to hold
the latter in the proper position in the wheel. In case the locomotive is provided
with a second pair of driving wheels J then the wrist pin E is made sufficiently long
to permit a connecting rod K to engage the said wrist pin in addition to the rod C,
as plainly illustrated in Figures 1 and 2. This rod K is connected with a
wrist-pin L on the second driving wheel J and the other wrist pin F of the first
driving wheel G is connected by a connecting rod N with a wrist pin O held on a
crank arm P attached to the outer end of the wrist pin L. This double
wrist pin O, L, and crank arm P are similar to the double wrist pin F, E, and
crank arm H on the first driving wheel G.
It will be seen that when steam is admitted to the cylinders A and B simul-
taneously their pistons travel in opposite directions, so that one of the connecting
rods C or D pushes rearward on its respective wrist pin while the other pushes
forward, and vice-versa, during the lower or upper half of the stroke. By this
arrangement all horizontal strain on the journals or the axles of the driving
wheels G and J is prevented, and pounding of the driving wheel on the rails is
obviated on account of the pressure on the two crank pins E and F being

page_text: simultaneously on the upper and lower half of the stroke, for each revolution of
the wheel.
It is understood that the block E¹ may be of any other desired form than
triangular, as stated and shown in the drawings.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :
1. A driving gear for locomotive engines, comprising a front cylinder, a rear
cylinder, the cylinders being located on opposite sides of the driving wheel, and
wrist pins located on opposite sides of the centre of the driving wheel and connected
with the connecting rod of the said engine cylinders, substantially as shown and
described.
2. In a driving gear for locomotive engines, the combination, with a driving wheel
having in its web a transverse aperture, of a block secured in the said transverse
aperture, a wrist pin formed or secured on the said block, a crank arm attached to
the outer end of the wrist pin and extending diametrically of the driving wheel, a
second wrist pin projecting from the free end of the said crank arm, and connecting
rods connected with the said wrist pins and forming part of the engine cylinders
arranged on opposite sides of the said driving wheel, substantially as shown and
described.
3. A driving gear for locomotive engines, comprising a front cylinder, a rear
cylinder, the said cylinders being located on opposite sides of the driving wheels,
wrist pins located on opposite sides of the centre of each driving wheel, a crank arm
for connecting the two wrist pins of one driving wheel with each other, cylinder
connecting rods connected with the wrist pins of one driving wheel, and parallel
connecting rods connecting the wrist pins of one driving wheel with the wrist pins
of the other driving wheel, substantially as shown and described.
Dated this 10th day of Me 1902
D. S. PATTERSON,
By A. M. & Wm. Clark,
53, Chancery Lane, London, Chartered Patent Agents.