IMPROVEMENTS IN LOCOMOTIVE ENGINES
Year: 1884

page_text: COMPLETE SPECIFICATION.
I JAMES ATKINSON LONGRIDGE of 15 Great George St in the City of
Westminster, Civil Engineer do hereby declare the nature of my invention for
IMPROVEMENTS IN LOCOMOTIVE ENGINES 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 improvements in locomotive engines of the kind
illustrated in Figure 2 of the specification of a former Patent granted to me dated
November 2nd 1872, Nº 3259 in which the boiler is supported on three swivelling
or bogie frames, the adjacent axles of the adjoining frames being geared together by
spur gearing and the frames themselves being connected by ball and socket
couplings. My present improvements have for their object to facilitate the passage
of the engine round sharp curves and to avoid undue strains upon the gearing or
couplings which would be caused by a change of gradient as well as those which
would be caused by inequalities in the level of the rails.
Reference is to be had to the accompanying drawings forming part of this
specification and to the letters and figures marked thereon.
Figure 1 illustrates a side elevation of a locomotive provided with the improve-
ments of my present Invention. Figure 2 is a cross section one half on the centre
line 1-1, and the other half on the line 2-2 Figure 1. Figure 3 is a plan of the
bogie frames only, the boiler being removed. Figure 4 is a cross section on the
line 3-3 figure 3. Figure 5 is a cross section on line 4-4 figure 3. Figure 6 is
a side view of one set of spur wheels by which the adjacent axles of two bogie
frames are geared together according to another patent hereafter referred to.
Figure 7 is an end figure 8 a side elevation and Figure 9 a cross section on line 5-5.
Figure 8, of the main bearing for the driving crank shaft, showing the slide blocks
by which the centre bogie frame is enabled to oscillate either in a fore and aft or in
a lateral direction, or to slide vertically, independently of the engine frame.
Figure 10 is a longitudinal section of the improved ball and socket coupling by
which the bogie frames are connected.
Figures 11 to 13 illustrate another improvement relating to the construction of
the boiler and to the mode of supporting the same upon five bogie frames.
Referring to figures 1 to 10, the boiler is supported upon compensating or
balance levers and in general principle and arrangement resembles that described in

page_text: my aforesaid Patent of 1872. The boiler is a double boiler with two fire boxes A A
and two barrels B B each containing a set of tubes having a downward inclination
towards the smoke boxes at the ends of the engine, return flues from the smoke
boxes running above the body of the boiler to one or more chimneys in the centre.
The boiler does not rest immediately on the bogie frames but upon two balance
beams D D, which beans rest at one end on the middle truck or frame C and at
the other end upon the centre of the leading and trailing frames C C² respectively,
the points of support of the boiler on the balance beams being so placed as to divide
the total weight of the boiler, engines and tanks between the several bogie frames
in the proportion of the number of wheels in each.
My first improvement has for its object to permit of the lateral oscillating motions
of the bogie frames independently of the balance levers which rest upon them. For
this purpose I make the bearing surfaces of the ends of the balance levers which
rest on the middle frame or truck in the form of a ball and socket constituted by a
hemi-spherical boss d (figure 4) resting in a corresponding cup c formed on a
stretcher between the side frames of the bogie truck C. This spherical bearing is
situated in the centre line of the truck C₁ so that the latter can yield to any
transverse inequality of the rails without causing any strain on the balance lever.
The ends of the balance levers which rest on the other bogies are of considerable
breadth and each rest upon a set of rollers E (figures 3 and 5) running on a roller
path F and radiating from the coupling between the bogie frames. The roller
plate F is supported at its ends on springs G of semi-elliptic or volute form carried
by the side frames of the bogie trucks whereby oscillating motion of the bogie
frame independently of the roller path is permitted. Further, to prevent any
strains upon the boiler consequent upon unequal oscillations of the two end trucks
springs H (figures 1 and 5) are interposed between the two balance levers and the
points of support of the boiler. These springs H are fixed in pairs, one at either
side of each balance lever, and take under brackets h fixed to the shell of the boiler
and form the four points of support upon which the entire upper portion of the
engine is carried. All lateral oscillations of the bogie frames are thus taken up by
the two sets of springs G H.
The second improvement relates to the connection of the engine framing with
the framing of the middle bogie in order to permit of the fore and aft and lateral
oscillations and the rising and falling motions of the latter independently of the
engine frame. The cylinders which are placed vertically at the middle of the
engine, one at either side are attached together with their cross head guides, each to
a vertical plate I (figure 1) fixed to the side of the boiler. This plate I is in two
parts I I' bolted together. The parts 11 (figures 7 and 8) carry the bearings in
which the main driving shaft S is mounted. Each bearing is formed of the usual
brasses fitted in a boss formed in the part 1. This boss has two circular segments i
concentric with the main or driving crank shaft, and between these segments and
the horn plates of the bogie frame are fitted slide blocks K. These blocks are
curved concentrically with and embrace the segments i, the segments and blocks
being rabbeted together so that the blocks can slide around the axis of the main
bearing. The outer edges of the slide blocks are grooved and rectilinear to slide
upon straight vertical guides L, carried by the horn plates, the flanges k of the
slide blocks being convexly curved on their inner surfaces, as shown in Figure 7.
By this means, the boiler is held in proper position upon the three bogie frames,
whilst the middle bogie frame is free to oscillate in a fore and aft direction about
the shaft S as a centre, or in the lateral direction, or to rise and fall without putting
apy strain on the engine framing.
My third improvement relates to the couplings of the bogie frames. The
transmission of the power from the main crank shaft to the wheels of the middle
bogie C¹ is effected by coupling rods, and from the axles of this bogie to the
adjacent axles of the bogies C C by sets of cog wheels M N M of which M M'are
mounted on the respective axles to be coupled by universal joints as described in a
previous Patent granted to me dated 22nd November 1877 N° 4389 and the middle

page_text: wheel N is mounted on a short axle turning in bearings in side frames O as in my
said former Patent. By this arrangement it is evident that the distance apart of
the axles so geared together is rigidly fixed. Consequently at a change of gradient
the distance of the ends of the bogie frames from each other must vary, and the
present improvement has for its object to enable this variation to take place
without throwing undue strains either on the couplings of the bogie frames or on
the wheel axles, and also to cause the tractive force to be borne chiefly by the
couplings.
The improvement consists in providing ball and socket couplings such as
described in my previous Patent of 1872 with springs which permit either of
elongation or of compression of the coupling, as the case may be. The improved
coupling is illustrated in figure 10, P being the ball and Q the socket respectively
attached to stems 2 9 passing through the ends of the bogies and secured by nuts.
The nuts and the shoulders of the stems slide in casings R, sets of indiarubber or
volute springs T being inserted at either side of the end plate of the bogie frame
and between it and the nut and shoulder on the stem. Instead of applying these
springs to the stems of both parts of the coupling, one stem may be rigidly fixed to
its frame, the other one only being provided with springs. In either case when the
bogie frames are coupled together the springs are compressed by tightening the nut
until the compression upon them is approximately equal to the tractive force which
will usually be exerted upon that coupling.
Figures 11 to 13 illustrate another improvement relating to the construction of
the boiler and the mode of supporting the engine on five bogie frames. I make
the boiler in two distinct portions A B, A¹ B¹ each of which is a duplicate of the
other but is complete in itself inasmuch as it has its own fire-box, fire-grate, tubes,
flues, and chimney. These two parts are, however, rigidly connected together by
a strong framing or plate bracing a a, to which they are bolted or rivetted leaving
a vacant space of two or three feet or more between the two fire-box onds.
In this space are placed the cylinders and gearing of the engine and the cylinders
work vertically above the main driving shaft.
The cylinders may be placed either inside the framing a a, which connects the
boilers, or outside, and the motion is transmitted to the wheels as described in my
previous patent of 1872.
The steam pipes leading to the cylinders are placed outside the Boiler in the
return flue and are connected at intervals by smaller vertical pipes with the top of
the Boiler shell as shown in the drawing. By this arrangement the steam is
superheated and priming is avoided either on a level or on steep inclines.
The two sections of the Boiler are united at or near the top of the Fire Box end
by one or more steam pipes B' which traverse the intermediate space between the
sections There is thus a free steam connection between the two sections but no
water connection in cases where this is desirable.
A further improvement consists in the introduction of circulating pipes and
tubes whereby the free and rapid circulation of the water throughout the boiler is
obtained.
This is attained first by the introduction of one or more conical tubes U in the
fire boxes which are open at top to the water in the Boiler and at the lower end
pass through the fire grate and are connected with one or more tubes or pipes u
leading to the bottom of the Boiler at the smoke box end.
Besides this other pipes or tubes are carried from the back or outside of the
fire box down and through under the fire grate to the body of the Boiler to which
they are attached at any point that may be desirable.
'
In compound engines the high pressure cylinders may be placed outside and one
large low pressure cylinder inside the framing which connects the fire box ends.
When very powerful engines are required, or engines to work on light rails and
with heavy gradients and severe curves, I place the boilers and cylinders as above
described on five trucks or Bogies C, C, C3, C4, C5 coupled as described in my
previous patent, and in a previous part of this specification. The centre bogie,

page_text: which carries the main or driving shaft, has only four wheels, the other bogies may
have four or six wheels as may be required.
By this means the adhesion may be utilized of 20 or 28 wheels all working as
driving wheels.
In order to distribute the weight equally over the wheels I make use of a
combination of balance beams arranged as follows. The whole weight of the
Boilers, Tanks, coal bunkers, cylinders &c is borne at four points by two double
balance beams D, D. Each of these balance beams rests on the end or near the
end of the frame of the centre bogie C³ on a pivot or hemispherical end & which
rests on a cup immediately below the axis of the Engine as previously described.
On this bogie there are therefore two points of support only.
Each beam D is composed of a transverse member passing below the fire-box
level and two side members passing alongside of the boiler to a point over the
coupling between the two next bogies C₁ C or C C (as the case may be) where
they are connected again by a transverse member forming a roller plate d¹.
On each of these side beams is a bearing for the Boilers &c which rest on
springs H and brackets has before. The position of these bearings is fixed by
the number of wheels in the middle Bogie as compared with the number in the
other bogies; for instance if the other bogies six wheeled bogies, there will be 28
wheels in all, therefore 14ths of the whole weight will be borne by each main
balance beam, of this ths will be borne by the middle bogie and the by each of
the adjacent bogies or ths by the other end of the balance beam; the point of
support will therefore be the from the pivot end and the from the roller
bearing end.
28
In order to distribute the the equally over the other bogies a secondary balance
beam D is employed for each pair of bogies C¹ C and C+ Co. This beam rests on
a pivot or hemi spherical ball end which rests on a cup at the centre of the bogie
(C or C) next the middle bogie and by a a roller bearing placed at the middle of
the other bogie In the middle of these secondary beams D₁ there is a roller plate
or bed on which the roller plate d¹ at the short end of the main balance beam D
rests, a set of rollers being interposed as in the former case, and thus the 11ths of
the weight is equally distributed over the 12 wheels of the two bogies at each end
of the engine.
These balance beams and roller plates are provided with springs as already
described in another part of this specification.
The water tanks, foot plates, and coal Lunkers are attached to the Boiler and
not to the bogie frames.
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 In a locomotive engine in which the superincumbent weight of the boiler is
distributed upon two adjacent bogie frames by means of a balance beam, the
construction of the point of support of one end of the balance beam in the form
of a ball and socket or universal joint, substantially as and for the purpose herein
described.
2nd In a locomotive engine in which the superincumbent weight of the boiler is
distributed upon two or more adjacent bogie frames by means of a balance beam,
supporting one end of the balance beam on a ball and socket or universal joint,
and the other end upon a rolling bearing carried upon springs whereby the
movements of the bogie frames due to inequalities of the rails are in great part
prevented from being transmitted to the balance beam and whereby the bogie
frames are enabled to adapt themselves to the curve of the line, substantially as
shown and described.
3rd The combination with a balance beam supported at one end on a ball
and socket and at the other on a rolling bearing, of springs interposed between
the balance beam and the boiler to carry the latter, substantially as shown and
described.

page_text: 4th In a locomotive engine in which power is transmitted to the driving wheels
of a bogie frame through the medium of a crank shaft hung in bearings on the
engine framing between the driving wheels of the said bogie frame but independent
of said frame, the combination with the circular guides around said bearings and
with the straight guides of the horn plate, of sliding blocks adapted to slide around
the axis of the crank shaft which permit of the fore and aft and lateral oscillations
and the rising and falling motions of the bogie frame independently of the crank
shaft bearings, substantially as shown and described.
5th In a locomotive engine supported on two or more bogie frames and in which
the adjacent axles of adjoining frames are geared together by spur gearing and the
frames are connected by ball and socket couplings as described, the combination
with the stems of the coupling of springs whereby the coupling is enabled to yield
to strains either of tension or compression in excess of the normal tractive strain
on the coupling, substantially as described.
6th The combination in a locomotive engine of two distinct boilers separated by
an intermediate space but connected together rigidly with the steam cylinders and
valve gear arranged vertically between them, substantially as described and shown
in figures 11 and 12 of the drawings.
7th In a locomotive engine the particular arrangement of the circulating pipes
or tubes as described.
8th In a locomotive engine in which the weight of the boiler is distributed over
five adjacent bogie frames, the combination and arrangement for that purpose of
two sets of superposed balance beams substantially as above described.
9th In a locomotive engine in which the weight of the boiler is distributed over
five bogie frames, the arrangement at each end of the engine of a set of superposed
balance beams each resting on a pivot bearing at one end and on a roller bearing at
the other for the purpose of dividing the amount of lateral motion between them
in traversing curves.