IMPROVEMENTS IN MARINE ENGINES
Year: 1877

page_text: LETTERS PATENT to James Humphry's, of Barrow-in-Furness, in the County
of Lancaster, Engineer, for the Invention of "IMPROVEMENTS IN MARINE
ENGINES."
aled the 29th September 1877, and dated the 26th May 1877.
PROVISIONAL SPECIFICATION left by the said James Humphrys at tho
Office of the Commissioners of Patents on the 26th May 1877.
JAMES HUMPHRYS, of Barrow-in-Furness, in the County of Lancaster, Engineer.
"IMPROVEMENTS IN MARINE ENGINES."
This Invention relates to certain improvements in marine engines, the advantages
obtained thereby being long connecting rods and eccentric rods, moderate sized low-
pressure cylinders, and support to crank shaft by means of central disc.
In carrying out the Invention the cylinders are placed as near the shaft as
practically convenient, the. high-pressure cylinders being on one side and the low-
pressure cylinders on the other side, the piston rods working through the ends of
the cylinders furthest from the shaft, with return connecting rods, vizt., a single rod
working between the two low-pressure cylinders, and double rods, one at each side
of the high-pressure cylinder, a central disc forming an additional support for the
crank shaft...

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said James Humphrys in the Great Seal Patent Office on the 26th
November 1877.
JAMES HUMPHRYS, of Barrow-in-Furness, in the County of Lancaster, Engineer.
"IMPROVEMENTS IN MARINE ENGINES."
This Invention relates to certain improvements in marine engines, the advantages
obtained thereby being long connecting rods and eccentric rods, moderate sized
cylinders, and support to crank shaft, if desirable, by means of central disc.
In carrying out the Invention the cylinders are placed as near the shaft as
practically convenient, the high-pressure cylinder or cylinders being on one side,
and the low-pressure cylinders on the other side, the piston rods working through
the ends of the cylinders furthest from the shaft, with return connecting rods, viz.,
a single rod working between the two low-pressure cylinders, and double rods, one
at each side of the high-pressure cylinder, where a single cylinder is employed, a
central disc forming an additional support for the crank shaft, if desirable.
And in order that the said Invention may be well understood, I shall now
proceed more particularly to describe the same, reference being made to the acconi-
panying Sheets of Drawings, like letters of reference indicating corresponding parts
in all the Figures.
Fig. 1, Sheet 1, represents a plan of one form of my Invention; and Fig. 2 a
.side elevation thereof.
A represents the high-pressure cylinder of a marine engine arranged longitudinally
on one side of the crank shaft B and C, C, the two low-pressure cylinders similarly
arranged and parallel to each other on the opposito side of the said shaft, these
cylinders being placed as near to the crank shaft B as practically attainable. The
piston rod D of the high-pressure cylinder A works through the end thereof
furthest from the crank shaft B, and terminates in the cross head E, which recipro-
cates in guides and communicates at its ends with the cranks a, a, on the shaft B
by two return connecting rods F, F. The piston rods G, G, of the two low-pressure
cylinders C, C, also work through the ends of the latter furthest from the shaft B,
where they are connected by a cross head H, from the middle portion of which,
where it works in guides, a single connecting rod 1 passing between the two low-
pressure cylinders C, C, communicates with the crank b on the shaft B, as shown.
At or near the centre of the crank shaft B is a disc K, which may be made to
revolve in a bearing, and so form an additional support to the said shaft.
A modification of my Invention in cases where the engines are of such size as to
render it desirable to employ two high-pressure cylinders is shown on Sheet 2 of
the Drawings, where Fig. 3 is a plan. In this arrangement A', A', represent the
two high-pressure cylinders; B, the crank shaft; and C, C', the two low-pressure
cylinders.
The piston rods D₁, D', of the high-pressure cylinders A', A', are connected at
their ends furthest from the crank shaft B', by the cross head E', from the middle
portion of which, where it works in guides, a single connecting rod F' passing
between the two high-pressure cylinders A', A¹, communicates with the crank a¹,
as shown.
The two low-pressure cylinders C¹, C', are arranged in a similar manner to the
two low-pressure cylinders C, C, in the arrangement previously described.
By the above arrangements the desideratum of long connecting rods and eccentric
rods is attained, moderate sized low-pressure cylinders may be used, and the use of
an additional support when required to the crank shaft produces the great advan-
tage of steadiness.
The other working details of the engines, being similar to those of the same class
in ordinary use, need no description.
Having now described and particularly ascertained the nature of my said Inven-

page_text: tion and the manner in which the same may be used or carried into effect, I would
observe in conclusion that what I consider novel and original and therefore claim as
the Invention secured to me by the herein-before in part recited Letters Patent is,
the arrangement of the cylinders and other working parts in marine engines,
substantially as and for the purpose herein-before described and illustrated by the
accompanying Drawings.
In witness whereof, I, the said James Humphrys, have hereunto set my
hand and seal, this 10th day of November, in the year of our Lord One
thousand eight hundred and seventy-seven.
JAMES HUMPHRYS. (L.S.)