IMPROVEMENTS IN SELF-ACTING COUPLINGS FOR THE DRIVING WHEELS OF MOUNTAIN LOCOMOTIVES
Year: 1877

page_text: LETTERS PATENT to Frank Wirth, of the Firm of Wirth and Company, Patent
Solicitors, at Frankfort-on-the-Main, in the Empire of Germany, for the Inven-
tion of "IMPROVEMENTS IN SELF-ACTING COUPLINGS FOR THE DRIVING
WHEELS OF MOUNTAIN LOCOMOTIVES." A communication from Richard Vogel,
Engineer, of Ibbenbüren, in the Empire of Germany.
PROVISIONAL SPECIFICATION left by the said Frank Wirth at the Office
of the Commissioners of Patents on the 31st August 1877.
FRANK WIRTH, of the Firm of Wirth and Company, Patent Solicitors, at
Frankfort-on-the-Main, in the Empire of Germany. "IMPROVEMENTS IN SELF-
ACTING COUPLINGS FOR THE DRIVING WHEELS OF MOUNTAIN LOCOMOTIVES." A
communication from Richard Vogel, Engineer, of Ibbenbüren, in the Empire of
Germany.
The improvements consist in hinging the driving couplings or connecting rods
supplied to locomotives so that they will bend to the curves and transmit power
at the same time; also in shifting the stroke of the piston laterally for the same
object.
The improvements can be performed by using the existing rolling stock and
furnishing the axles, and, in some cases, the wheels with suitable cranks for receiving
the ends of the various coupling rods; the hinged connection is effected by means
of a pin fitted into two ends of the rod, which is made in two pieces with the ends
formed in the shape of jaws to embrace each other, through the cheeks of which
jaws the pin is passed so as to join the rods together, but yet allow of their lateral
play, or other convenient modes of fastening may be employed.
The lateral deviation of the driving piston is effected by forming the rod of two
or more pieces with hinged connections similar to those above described, but
furnished with butts or stops to control the deviation beyond a certain point.
Price fd1

page_text: The object of the Invention is to couple all the driving wheels of a locomotive
together, and so obtain greater adhesion for mounting inclines and allow of the
locomotive going round sharp curves by rendering the connecting coupling rods
flexible by hinging them when in pieces, or by other convenient device.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Frank Wirth in the Great Seal Patent Office on the 27th February
1878.
FRANK WIRTH, of the Firm of Wirth and Company, Patent Solicitors, at
Frankfort-on-the-Main, in the Empire of Germany. "IMPROVEMENTS IN SELF-
ACTING COUPLINGS FOR THE DRIVING WHEELS OF MOUNTAIN LOCOMOTIVES." A
communication from Richard Vogel, Engineer, of Ibbenbüren, in the Empire of
Germany.
The improvements consist in so hinging the driving couplings or connecting rods
supplied to locomotives that they will yield to the curves and transmit power
at the same time; also in shifting the stroke of the piston laterally for the same
object.
The improvements can be performed by using the existing rolling stock and
furnishing the axles, and, in some cases, the wheels with suitable cranks or studs
for receiving the ends of the various coupling rods.
The accompanying Drawing represents elevation, plan, and sections of this coupling
on one side of the engine, and is intended to illustrate a mode of performing the
Invention.
Two frames turning on the pivot F carry 5 axles, the hind frames carrying the
axles A and B; the front, the axles C, D, and E; the axles of each frame are coupled
to each other in the ordinary manner by the connecting rods G, H, and Z; the
outward form of the rod H being somewhat different from the general shape, and
consists of a strong rail to which a moveable bearing or plumber block is attached
as a bearing for the piece K.
The two axles B and C of the two carrying frames are connected with a move-
able coupling, which, with full transmitting power, permits the two carrying frames
of the locomotive to take radial positions in passing over a curve.
The following description, together with the Drawing, clearly shews the In-
vention On the coupling pivot of the axles B, C, a coupling is attached, consisting
of two chief parts N and O, placed in a vertical plane with the centre of the steam
cylinder; the part N carries the moveable pivot d upwards and downwards by
equally long and equally divided vertical double levers P, P¹; N is then continued
backward and provided with a cylindrical end bearing in an exact boring in the
piece O. The piece O, when looked at by itself, forms a sort of cross, the ends of
the cross piece being connected by the rods I and I¹ to the ends of the double
levers P, P¹; this connection is formed at each end of the rods by the moveable
bolts a, a, b, b¹.
From the piece M having its bearing in K, two rods G, G', are extended to the
double levers P, P¹, and forming with their clasping pieces c, c¹, a fulcrum for the
double levers P, P¹.

page_text: M is a vertical axle; e, e¹, moveable horizontal axles, and the connecting moveable
bolts f, f, and g, g¹, cross at right angles the turning axles of their clasping pieces;
the result is thus obtained that the rods q, q', cannot only move in a vertical plane
but also swing horizontally.
As the machine passes over a curve, the distance between the coupling axles B
and will alter. The result of this being that the levers incline, and the rods q, q',
and I, I', converge, and the axis of the piece K forms an angle in an horizontal plane
with the axis of the coupling hanging on B and C; it is therefore necessary that
the rods q and q¹ can move in a horizontal as well as in a vertical direction. During
this movement the play of the piston in the steam cylinder will be somewhat shifted
from the middle through the connecting rod fastened to K. This shifting will be
towards the back of the cylinder, running on the convex side of the curves, and
towards the front of the outside cylinder; that is, the one running on the concave
side of the curve.
As the steam cylinder and the axle carrying the eccentrics are on the same frame,
the radial position of the two frames to each other in going over curves has no
effect on the valve gearing, the only difference caused being an alteration of the
dead space in the cylinder and the unequal compression of the steam on both sides
of the piston.
If the proportions of the double lever are chosen as follows, dc: ca=de:cb=2:3,
then the travel of the piston shifted 6 millemeters at each end gives almost 15 mille-
metres play for the coupling pivots, the difference between the coupling pivots on
the one side and the coupling pivots on the other side being nearly 30 millemeters.
Thus a difference is obtained which would suffice under almost any circumstances.
The movement of the driving axles is accomplished as follows:-The power is
transmitted by K, M, and the rods q, q', from the connecting rod to the pieces c, c¹;
thereupon the ends of the double levers work upon N and O, thus causing the whole
of the axles to turn round in one direction.
It is necessary that the bearings of the levers P, P¹, be properly chosen in order
that the power transmitted by c, c¹, does not damage them when moved out of their
normal position by the locomotive going over a curve.
The power necessary to drive the axles C, D, E, must be in proportion to dc or
de, to the power necessary for the axles A, B, C, to ca or cb. These proportions
however cannot be exactly maintained through the whole of a journey, as even if
the water for the engine is carried in another wagon and not in the tender, even
then the unequal feeding of the boiler and consumption of fuel make differences in
weight.; nevertheless the friction of the wheels on the rails causes sufficient pro-
tection against such differences.
So long as the axles belonging to one frame do not slip, the whole force of the
machine is expended in pulling the train. It is however impossible for the axles of
one frame to slip without the axles of the other frame slipping also, which however
is prevented by the coupling, as the latter would have to swing out of the horizontal
between B and C, the double levers be forced into an angle, and a, a, together
with f, f, out of the vertical, which is impossible when good workmanship has been
used.
The cylindrical end of the piece N fitting into O is fastened with a draw wedge
in such manner as to allow room for the play caused by the shifting of the travel
of the piston, and to prevent the coupling turning round and round the ball
pivots B and C; the two forks x and y are placed embracing the coupling rods H
and Z.
Having thus fully described my Invention, I claim,―
1st. A connecting coupling moving at curves, and at the same time transmitting
full power, as described.
2nd. The mechanism of the coupling, allowing the travel of the piston to be
shifted.
3rd. The double levers P, P', the rods I, I, and q, ql, the main pieces O and N,
the bolts a, a¹, b, b¹, c, c¹, d, d¹, f, f¹, a, a¹, the piece K with its bearing L. in

page_text: connection with H, the ball pivots on B and C, all substantially as shown and
described.
In witness whereof, I, the said Frank Wirth, have hereunto set my hand and
seal, this Eighteenth day of February, in the year of our Lord One thousand
eight hundred and seventy-eight.
FRANK WIRTH. (LS)