IMPROVEMENTS IN LOCOMOTIVE ENGINES
Year: 1884

page_text: I, ALEXANDER MELVILLE CLARK, of the firm of A. M. and Wm. Clark, of
53, Chancery Lane, in the County of Middlesex, Fellow of the Institute of Patent
Agents, do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
LOCOMOTIVE ENGINES a communication to me from abroad by Gabriel Fretel of
Rio de Janeiro in the Empire of Brazil, Engineer, to be as follows :-
"
This Invention relates to improvements in locomotive engines whereby the
requisite flexibility of wheel base, to enable the engine to run on curves of very
small radius, is combined with great tractive power, obtained by coupling together
a large number of driving wheels. As many as nine pairs of driving wheels may
be coupled together, thus giving great adhesion on the rails, and the engine is
therefore especially suited for railroads in mountainous districts having steep
grades and sharp curves.
The Invention consists essentially in the means hereafter described, whereby the
coupling rods of the driving wheels are automatically lengthened or shortened
according as they may be on the inner or outer side of the curve on which the
engine is running.
The main frames of the locomotive and tender are supported on four intermediate
frames, to which they are connected by centre pins, the intermediate frames being
jointed together so as to be capable of flexure to suit the curvature of the road, and
are supported in turn upon bogie frames and intermediate pairs of wheels arranged
and coupled as follows:
The first intermediate frame beneath the engine is supported at the front end
upon a bogie or swivelling frame having a single pair of driving wheels and two
pairs of guide wheels which take no part of the weight. The axle of the second
pair of driving wheels is capable of longitudinal sliding motion in its axle boxes for
the purpose of enabling the wheels to move laterally, and so adapt themselves to
the curvature of the rails. This pair of wheels is situated immediately beneath the
centre pin which connects the main frame of the engine to the centre of the first
intermediate frame. The third pair of wheels is mounted in a bogie frame the
centre pin of which is the joint pin connecting the first and second intermediate
frames beneath the engine. The axle of the fourth pair of wheels is capable of
longitudinal motion like the second pair, and is situated directly under the centre
pin connecting the main frame of the engine to the second intermediate frame.
The fifth pair of wheels is mounted in a bogie frame provided with guide-wheels
like the first the centre, pin being also the joint pin connecting the second and third
intermediate frames. The succeeding four pairs of wheels beneath the tender are
similarly arranged in the order above mentioned, all these wheels except the guide

page_text: wheels being drivers, and coupled by rods which are automatically variable to suit
the curvature of the road as hereafter described.
The piston-rod connecting rods are connected in the ordinary way to the crank
pins of the third pair of drivers.
BIB
The coupling rods of the driving wheels have vertical joints at the ends which
admit of flexure at these points of the coupling rods in the horizontal plane, and
the connection of the coupling rods with those wheels whose axles are capable of
longitudinal sliding motion in their bearings (that is to say the intermediate or
2nd and each succeeding alternate pair of wheels) is made by one or other of the
following contrivances whereby the automatic variation in length of the coupling
rods is effected by the longitudinal sliding motion of the axle.
Referring to one driving wheel only, the coupling rods are jointed by vertical
joints to sliding blocks fitted to slide in horizontal guides in a frame carried by the
crank pin of said wheel, and in line with the coupling rods, through the middle of
which frame the crank pin is free to slide transversely when the wheel axle slides
in its bearings, this frame being supported so as to be held stationary relatively to
said sliding motion of the crank pin (whilst being free to accompany the crank pin
in its revolution) by attachment by ball and socket joints to cranked suspension
shafts.
According to one arrangement for producing the variation of length of the
coupling rods the sliding blocks to which they are jointed are actuated by pairs of
fast pitch right and left screw spindles mounted above and below said blocks and
engaging therewith and passing above and below the crank pin which is furnished
with a rack that gears above and below with pinions on the middle portions of the
right and left screw-spindles, whereby as the crank pin slides in or out transversely
through the middle portion of the guide frame, the pairs of right and left screws
are rotated in one or other direction, and the .slide blocks to which the coupling
rods are jointed are drawn towards or moved away from the crank pin; the
arrangement and motion of the parts being symmetrical at the front and rear sides
of the said pin whereby the coupling rods are lengthened or shortened as the case
may be.
According to the other arrangement instead of the rack pinion, and screw gear
the crank pin carries a frame which slides with the crank pin transversely through
the guide frame of the coupling-rod slide-blocks, and which has a pair of oppositely
inclined oblique arms that slide through corresponding slots in the sliding blocks
and their guide-frame whereby the transverse sliding motion of the inclined arms
of the frame is converted into a longitudinal sliding motion of of the slide blocks of
the coupling rods thereby lengthening or shortening the latter as the case may be.
It is of course evident that whichever arrangement is adopted contrary effects
are produced at opposite sides of the engine by the same sliding motion of the
axles, the rods at one side being shortened whilst those at the other are lengthened
and vice versa according as they are on the inside or outside of the curve.
By the means herein described the automatic variation in length of the coupling
rods is effected without interfering with the transmission of motion by them to the
various wheels,
In connection with wheels whose axles slide as described may be used a pair of
oblique grooved guide wheels running against the inner edges of the rails said
guide wheels being carried by a sleeve on the driving wheel axle which can slide
therein so that said sleeve always remains central of the track whilst the driving
wheels themselves which are devoid of flanges can move towards the inside or
outside of the rails as circumstances may require.

page_text: I, ALEXANDER MELVILLE CLARK, of the firm of A. M. and Wm. Olark, of
53, Chancery Lane, in the County of Middlesex, Fellow of the Institute of Patent
Agents, do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
LOCOMOTIVE ENGINES" (a communication to me from abroad by Gabriel Fretel of
Rio de Janeiro in the Empire of Brazil, Engineer,) 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 improvements in locomotive engines whereby the
requisite flexibility of wheel base, to enable the engine to run on curves of very.
small radius, is combined with great tractive power, obtained by coupling together
a large number of driving wheels. As many as nine pairs of driving wheels may,
be coupled together, thus giving great adhesion on the rails, and the engine is
therefore especially suited for railroads in mountainous districts having steep grades
and sharp curves.
The Invention consists essentially in the means hereafter described, whereby the
coupling rods of the driving wheels are automatically lengthened or shortened
according as they may be on the inner or outer side of the curve on which the
engine is running.
.
Reference is to be had to the accompanying drawings forming part of this
Specification in which the same letters of reference indicate corresponding parts in
all the figures.
Figure is a plan showing the first and part of the second intermediate frame
and the bogie frame and wheels supporting the locomotive in the position they.
occupy when running on a curve.
Figure 2 is a side elevation on a smaller scale of the main frame, intermediate
frame, bogie frames, and wheels of the locomotive and tender.
Figure 3 is a sectional elevation of the leading bogie.
Figure 4 is a half sectional plan and figure 5 a half sectional longitudinal;
elevation (the sections being taken on lines x x, y y, respectively) of the means
shown in figures 1 and 2 for automatically lengthening or shortening the coupling
rods.
:
Figures 6 and 7 show elevations (on a larger scale) of two forms of joint for
connecting the coupling rods to the crank pins of those driving wheels whose axles
do not have longitudinal play (Nos. 1, 3, 5, 7 and 9).
Figure 8 is a longitudinal elevation (partly in section on line xx figure 9)
figure 9 a plan (partly in section' on line y y figure 8) and figure 10 a cross section
(on line figure 8) of a modification of the means shown in figures 1, 2, 4 and 5;
for automatically lengthening and shortening the coupling rods.
Figure 11 is a cross section of part of the locomotive, frame, showing a modifi-
cation having for object to ensure the radiation of the axles by means of guide
wheels and flangeless inwardly coned drivers. Figure 12 shows the section of the
rail to be used with this last arrangement,

page_text: Referring to figures 1 to 7, the main frames V and Z of the locomotive and
tender are supported on four intermediate frames A¹ A' A³ A' to which they are
_connected by centre pins vv, zz, situated at the middles of the said intermediate
frames which are jointed together at the ends so as to be capable of flexure to suit
the curvature of the road and are supported in turn upon pivots a carried by
leading intermediate and trailing bogie frames and by intermediate pairs of wheels
Nos. 3 and 7, the whole of the wheels being arranged and coupled as follows:
The first intermediate frame A¹ beneath the engine is supported at the front end
upon a bogie.or swivelling frame B¹ having a single pair of driving wheels N° 1 and
two pairs of guide wheels b which take no part of the weight, the construction of
the bogie being shown in figure 3. The axle of the second pair of driving wheels
No 2, is capable of longitudinal sliding motion in its axle boxes for the purpose of
enabling the wheels to move laterally, and so adapt themselves to the curvature of
the rails. This pair of wheels is situated immediately beneath the centre pin v
which connects the main frame V of the engine to the centre of the first intermediate
frame A¹. The third pair of wheels N° 3 is mounted in a bogie frame, the centre
pin a of which is the joint pin connecting the first and second intermediate
frames A¹ A² beneath the engine. The axle of the fourth pair of wheels N° 4 is
capable of longitudinal motion like the second pair and is situated directly under
the centre pin connecting the main frame V of the engine to the second intermediate
frame A. The fifth pair of wheels No 5 is mounted in a bogie frame provided
with guide-wheels b like the first, the centre pin of the bogie being also the joint
pin connecting the second and third intermediate frames A² A³ and situated beneath
the coupling of the locomotive and tender frames V Z. The succeeding four pairs
of wheels Noв 6, 7, 8 and 9 beneath the tender are similarly arranged in the
order above mentioned. Thus, the axles of NOB 2, 4, 6 and 8 are capable of
. longitudinal sliding motion, whilst those of Nos 1, 3, 5, 7 and 9 are mounted in bogie
frames. All these wheels (except the guide wheels b) are drivers, and are coupled
by rods which are made automatically variable to suit the curvature of the road as
hereafter described.
The cylinders C are suitably supported at the front of the main frame V of the
engine and the piston rod connecting rods c are connected by vertical pivots to
sleeves on the crank pins of the third pair of drivers N° 3, so as to permit of
the obliquity due to the radiation of this axle.
'
The coupling rods D connecting the several pairs of driving wheels together have
vertical joints at the ends which admit of flexure at these points of the coupling
rods in the horizontal plane, and the connection of the said coupling rods with
those wheels whose axles are capable of longitudinal sliding motion in their
bearings (i. e. the 2nd, 4th, 6th and 8th pairs of wheels) is made by one or other of
the following contrivances, whereby the automatic variation in length of the
coupling rods D is effected by the longitudinal sliding motion of the axle. One of
such arrangements is shown in figures 1, 2, 4 and 5 and another in figures 8, 9
and 10.
Referring to one driving wheel only of one of the pairs above referred to, the two
coupling rods D which connect with said wheel are jointed by vertical joints & to
sliding blocks E fitted to slide in line with the coupling rods in horizontal guides f
in a frame F through the middle of which passes, and which is carried by, the crank
pin of said wheel. Through the middle of this frame F the crank pin G is free to
slide transversely when the wheel axle slides in its bearings, this frame F being
supported so as to be held stationary relatively to said sliding motion of the crank
pin (whilst being free to accompany the crank pin in its revolution) by attachment
by ball and socket joints h to cranked suspension shafts H journalled in frames
supported by the bogie frames.
According to the arrangement shown in figures 1, 2, 4 and 5 the crank pin G
carries and revolves freely in a frame K which slides with the crank pin trans-
versely through the guide frame F of the coupling rod slide-blocks E, and which

page_text: frame K bas a pair of oppositely inclined oblique arms k that slide through
corresponding slots in the sliding blocks E and their guide frame whereby the
transverse sliding motion of the inclined arms k of the frame K is converted into a
longitudinal sliding motion of the slide blocks E thereby lengthening or shortening
the coupling rods D as the case may be.
l
According to the other arrangement for producing the variation of length of the
coupling rods shown in figures 8, 9 and 10, the sliding blocks E to which the
coupling rods D are jointed as above described are actuated by pairs of oppositely
threaded fast pitch right and left screw spindles L L mounted in frame F above and
below said blocks E with which the screw threads of said spindles engage. The
screw spindles passing above and below the crank pin G which is furnished with a
sleeve M having rack teeth m that gear above and below with pinions on the
middle portions of the right and left screw-spindles L, whereby as the crank pin G
slides in or out transversely through the middle portion of the guide frame F, the
pairs of right and left screws L L are rotated in one or other direction, and the
slide blocks E to which the coupling roda D are jointed as before described are
drawn towards or moved away from the crank pin G, the arrangement and motion
of the parts being symmetrical at the front and rear sides of the said pin, whereby
the coupling rods D are lengthened or shortened as the case may be.
It is of course evident that whichever arrangement is adopted contrary effects
are produced at opposite sides of the engine by the same sliding motion of the
axles, the rods at one side being shortened whilst those at the other are lengthened
and vice versa according as they are on the inside or outside of the curve.
Figures 6 and 7 show the mode of jointing the coupling rods D to the crank
pins of those wheels (No 1, 3, 5, 7 and 9) whose axles have no longitudinal motion.
In figure 6 the rods D are pin jointed on horizontal axes at d¹ to forked heads D₁
whose limbs overlap one another and embrace a box D2 carried by the crank
pin G¹ which turns freely therein, the forks being pin jointed on a vertical axis
at d³ to said block. In figure 7 the box D2 has ears to which the forked heads D'
of the coupling rods D are pin jointed at d³ on a vertical axis, the coupling rods D
being jointed at d' as before to the heads D¹ or rigidly attached thereto.
By the means herein before described, the automatic variation in length of the
coupling rods is effected without interfering with the transmission of motion by
them to the various wheels.
Figures 11 and 12 represent a modification which may be used in connection
with those wheels whose axles slide as described. This arrangement has for its
object, whilst maintaining the action of the mechanism for effecting the automatic
lengthening and shortening of the coupling rods, to facilitate the radiation of the
axle and maintain it in position over the line. To ensure this result two pairs of
oblique grooved guide wheels J running against the inner bevel of the rails, said
guide wheels being carried by a sleeve on the driving wheel axle, which sleeve
always remains central of the track whilst the driving wheels themselves which are
devoid of flanges can move towards the inside or outside of the rails as circum-
stances may require. These wheels are coned inwardly i.e. in the reverse direction
to the ordinary way and run on the outside bevels of the rail shown in figure 12,
their conicity being calculated according to the radius of the sharpest curve they,
have to traverse. They are of considerable width of tread so as to run on unequal
diameters in traversing curves. In the former arrangements the wheels are fast
on their axle, but here they are loose and free to slide on the axle and are con-
nected to the frame A by the bearings in which not the axle but the wheel hubs
turn without shifting longitudinally. To the ends of the axle are fixed the cranks
whose pins are prolonged at the inner end and enter holes in the wheels so as to
slide in and out thereof according to the position which the wheels are caused by
their conical tyres to assume on the rail. In figure 11 the left wheel is at the inner
side of the curve and runs on its smallest diameter, whilst the right hand wheel
runs on the largest diameter, the wheels and frame A thus together approaching

page_text: the centre of the curve, whilst the cranks are kept by the guide wheels J always
in the same place with regard to the track. As the guide blocks of the coupling
rods are connected to frame A, this opposite motion produces the lengthening and
Bhortening of the coupling rods as before described.
Having now particularly described and ascertained the nature of the said
Invention and in what manner the same is to be performed I declare that what
I claim is.
1st A locomotive having the driving wheels coupled by rods so connected as to
be automatically adjustable as to length substantially as herein shown and described
and for the purpose set forth.
"
2nd A locomotive having driving wheel coupling rods connected at one end to
sliding blocks in frames or boxes mounted on the crank pins of wheels whose axle
is capable of lateral motion, substantially as herein shown and described and for the
purpose set forth.
3rd A locomotive having driving wheel coupling rods pivoted at one end to
sliding blocks mounted in a frame on the crank pins of wheels whose axle is capable
of lateral motion in combination with devices for moving the sliding blocks longi-
tudinally in the boxes, substantially as herein shown and described and for the
purpose set forth.
4th The combination with the end and middle driving wheels of a locomotive, of
coupling rods pivoted to boxes on the crank pins of the wheels whose axles have a
swivelling motion and to blocks sliding in boxes mounted on the crank pins of
the wheels whose axles are capable of lateral motion relatively to the engine frame,
which crank pins are provided with devices for effecting by the relative motion of
the crank pins and boxes, the automatic extension and contraction of the coupling
rods, substantially as herein shown and described and for the purpose set forth.
5th In a locomotive, the combination with the pistons and piston rods and three
pairs of driving wheels or one section of the frame thereof, of connecting rods con-
necting the piston rods with the rear set of driving wheels, and coupling rods
connecting the rear pair of driving wheels with the middle and front pairs of
driving wheels, the coupling rods being pivoted to the front and rear pairs of
driving wheels, and to blocks held to slide in boxes mounted on the crank pins
of the middle pair of driving wheels, which crank pins are provided with devices
for effecting by the relative lateral motion of the said boxes and crank pins, the
automatic extension and contraction of the coupling rods, substantially as herein
shown and described and for the purpose set forth.
6th A locomotive engine of which the axles of the 1st 3rd 5th &c. pairs of coupled
driving wheels are mounted in bogie frames and those of the alternate 2nd 4th &c.
pairs of coupled driving wheels are so mounted as to be capable of lateral motion
relatively to the engine frame (i. e. motion in the direction of their length) and in
which the whole of the driving wheels are coupled by rods pivoted to the crank
pins of those wheels which have a swivelling motion and connected to the crank
pins of those wheels whose axles have a lateral motion, by means of slides and
devices, whereby the coupling rods are lengthened and shortened automatically by
the relative lateral motion of the crank pins and coupling rod slides, substantially
as shown and described.
7th The combination of mechanism shown in figures 4 and 5, consisting of the
double inclined guides, guide boxes and slide blocks applied to the crank pins and
coupling rods for producing by the lateral motion of the crank pins relatively
to the said boxes, the automatic extension and contraction of the coupling rods
substantially as specified.
8th The combination of rack and screw mechanism applied to the coupling rods
and to the crank pins of a pair of locomotive driving wheels for effecting by the
lateral motion of the axle relatively to the supporting frame, the automatic
lengthening and shortening of the coupling rods substantially as herein described &
and shown in figures 8, 9, and 10.

page_text: 9th The combination with the crank pin of a locomotive driving wheel, of a
box on the crank pin, and of connecting rods having forked ends pivoted to the box
in such a manner that the connecting rods can turn laterally on the pivots on the
box, substantially as herein shown and described, and for the purpose specified.
Dated this 28th day of February 1885