IMPROVEMENTS IN COUPLED- WHEEL LOCOMOTIVES
Year: 1879

page_text: LETTERS PATENT to John Imray, of Southampton Buildings, Chancery Lane,
in the County of Middlesex, for the Invention of "IMPROVEMENTS IN COUPLED-
WHEEL LOCOMOTIVES." A communication from abroad by Frederic Weidkuecht,
of Paris, France. Engineer.
Sealed the 4th April 1879, and dated the 11th February 1879.
COMPLETE SPECIFICATION filed by the said John Imray at the Office of the
Commissioners of Patents on the 11th February 1879.
ور
JOHN IMRAY, of Southampton Buildings, Chancery Lane, in the County of
Middlesex. "IMPROVEMENTS IN COUPLED-WHEEL LOCOMOTIVES.' A communication
from abroad by Frederic Weidknecht, of Paris, France, Engineer.
For railways, particularly those of the light kind having steep gradients and sharp
curves, the locomotives have to exert great tractive force, and consequently it is
necessary to have a number of driving wheels in action. Owing to the curves of
the line it is difficult to apply coupled-wheels on one engine, and hence recourse is
often had to two or more separate engines coupled together, which is objectionable
on account of expense and other disadvantages. This Invention relates to means of
combining on one engine several sets of driving wheels in such a manner as to
permit the engine to run on sharp curves without strain on the driving gear. The
arrangements for this purpose may be varied in design and proportions but the
principles on which they are contrived will be understood by a description of the
accompanying Drawings representing several types of locomotive engines with
driving wheels coupled according to this Invention. The Drawings on Sheet I.
shew an arrangement of four axles or eight wheels coupled; Fig. 1 is a side view
partly in section; Fig. 2 is a vertical transverse section, one half being taken through
the shaft C (Fig. 1), and the other half through the locking frame G; and Fig. 3 is a
plan, the boiler being supposed removed to shew the mechanism below. On each
side of the boiler there is a cylinder A the piston of which has a rod extending each
way, each of these rods being linked by a connecting rod b to an arm or beam B
fixed on a rocking shaft C. Each of the shafts C extends inwards towards the
middle line of the engine and has at its inner end an arın c.
Each of those arms c
is linked by a connecting rod D to a crank on an intermediate shaft E. Each pair
of the shafts E is mounted on a locking or bogie frame G directly under its centre
of movement, so that there is freedom for the radial movement of these shafts when
the engine runs on a curve. In order to permit of this movement the connecting
rods D are jointed spherically to the cranks on the shafts E or have a jointing
Price 8d 1

page_text: thereto on two axes permitting motion in a horizontal as well as in a vertical plane.
The boiler, cylinders, beams B, and rocking shafts C, are all mounted on a rigid
framing X provided with cylindrical sockets F which rest on the locking frames G
that carry the shafts E and also the framing and bearings respectively of the two
pairs of driving axles, each pair having their four wheels which are driven coupled
by connecting rods K from cranks on the outer ends of-the-shafts-E: These
cranks on the one side of the engine as well as the inner cranks on the same shaft
E in each case are_at_right angles or nearly so to those on the other side of the
engine, so as to provide against dead centres in the course of their revolution in the
usual way.
-The-Figures-on-Sheet II. of the accompanying Drawings shew a modified con-
struction, Fig. 1 being a longitudinal, and Fig. 2 a transverse section, and Fig. 3 a
sectional plan under the boiler. In these Figures the letters employed to indicate
the various parts are the same as those employed to indicate corresponding parts in
the Figures on Sheet I. In this case the cylinders A are situated near one end of
the locomotive, and their pistons work in the usual way intermediate rotating shafts
C by cranks at right angles or nearly so. Cranks cat the inner ends of the shafts
C by means of inclined connecting rods D work the secondary shafts E, which in
As formerly
their turn by cranks & and connecting rods K work the driving axles.
described each pair of the shafts E with the two axles driven by them and their
four wheels are mounted on locking frames G, and the connecting rods D have
spherical or duplex jointing to the cranks on E to allow for the locking movement.-
The Figures on Sheet III. of the accompanying Drawings shew diagrammatically
various modified arrangements of driving mechanism of the kind described above.
In Fig. 1 the arrangement generally resembles that shewn more in detail in Sheet I.,
except that a single hind axle H with its one pair of wheels is worked from the
hinder arm or beam B. The arrangement shewn by the side view Fig. 2 (Sheet
III.) and plan Fig. 3 partly resembles that shewn more in detail in Sheet II., but
in this case the hinder piston rods from the cylinders A by connecting rods f drive
the one hinder axle H whilst the front piston rods by connecting rods b drive the
intermediate shafts C, and the cranks c on the inner ends of these shafts by the
connecting rods D drive the secondary shafts E which in their turn by connecting
rods K work the two front driving axles which along with the shafts E are
mounted on a locking frame. In the arrangement shewn in side view by Fig. 4
(Sheet III.), and in plan by Fig. 5, two pairs of driving wheels in front and two
pairs behind are worked as described with reference to the Figures on Sheet I., and
besides these an intermediate driving axle P with its wheels is worked by con-
necting rods Q from the arms B extended downwards from the front rocking shafts
C, ten coupled driving wheels being thus provided.
Having thus described the nature of the said Invention, and the manner in which
the same is to be performed as communicated to me by my foreign correspondent;
I claim,―
First. The method substantially as herein described of working the driving
wheels of locomotives when they are mounted on bogie or locking frames, by
mounting on the same frames under the centres of their motion crank shafts coupled
to the driving axles, these shafts being worked by connecting rods linked to their
cranks by spherical or duplex joints permitting the locking movement.
Second. The construction and arrangement of mechanism for working from two
sets of rocking shafts two pairs of driving axles of a locomotive, each pair being
mounted on a locking frame as herein described with reference to the Figures on
Sheet I. of the accompanying Drawings.
Third. The modified arrangement of the mechanism referred to in the preceding
claim in which a single driving axle H is substituted for one of the pairs of locking
axles as herein described with reference to Fig. 1 on Sheet III. of the accompanying
Drawings.
Fourth. The modified arrangement of the mechanism referred to in the second
claim in which, besides the two pairs of axles on locking frames, a fifth driving axle

page_text: P is worked from one of the rocking shafts C, as herein described with reference to
Figs. 4 and 5 on Sheet III. of the accompanying Drawings.
Fifth. The construction and arrangement of mechanism for working by oblique
connecting rods from intermediate shafts two pairs of driving axles of a locomotive,
each pair being mounted on a locking frame as herein described with reference to
the Figures on Sheet II., of the accompanying Drawings.
Sixth. The modified arrangement of the mechanism referred to in the preceding
claim in which a single driving axle H is substituted for one of the pairs of axles,
as herein described with reference to [Figs. 2 and 3 on Sheet III. of the accom-
panying Drawings.
In witness whereof, I, the said John Imray, have hereunto set my hand and
scal, this Eleventh day of February, in the year of our Lord One thousand
eight hundred and seventy-nine.
JOHN IMRAY. (L.S.)