Improved Form of Circular or Piston Valve.
Year: 1890

page_text: Date of Application 22nd Sept., 1890
Complete Specification Left, 22nd July, 1891—Accepted, 22nd Sept., 1891
PROVISIONAL SPECIFICATION.
[Communicated from abroad by HUGO MACCOLL, Engineer, Fabrica de Portilla,
White y Ca., Sevilla, Spain.]
Improved Form of Circular or Piston Valve.
HUGH MACCOLL Engineer Glasgow County of Lanark, do hereby declare the
nature of this invention to be as follows:-
The invention consists in an improved form of circular or piston valve for the
distribution of steam, water, or other gases or liquids in the cylinders of engines or
other motors.
The improvement consists in making the said piston valves suitable for the
admission of the steam or other equivalent to double ports at each end of the
cylinder in place of single ports.
The improvement is equally applicable to valves in which the steam &c. enters
at the ends & exhausts at the middle & to those in which the steam enters at the
centre & exhausts at the ends.
Suitable passages are formed in the valves for the conveyance of the entering
steam to the ports in the cylinders more distant from the entrance steam pipe;
& for the passage of the exhaust steam from the cylinder ports more distant from
the exhaust pipe.
The shape of these ports can be varied according to the nature of each particular
case in which the improvement is applied.
Dated this 16th day of September 1890
COMPLETE SPECIFICATION.
Improved Form of Circular or Piston Valve.
HUGH MACCOLL, Eldon Villas, Mount Florida, Glasgow, communicated to me
by Hugo MacColl of Seville Spain do hereby declare the nature of this invention
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 and comprises an improved construction and arrangement
of circular or piston valve for the distribution of steam, water, or other gases or
liquids in the cylinders of engines or other motors :-That is to say:-1 make the
valve of such a form as shall allow of the admission of the steam or other equivalent
to two or more ports at each end of the cylinder during the period of admission,
and which shall also allow the steam or other equivalent to escape from the same
ports during the period of exhaust. Suitable passages are formed in the valve
for the conveyance of the entering steam or other equivalent to the ports in the
cylinder more distant from the entrance pipe, and for the passage of the exhaust
steam or other equivalent from the ports more distant from the exhaust pipe.
The number and shape of these passages can be varied according to the nature
of each particular case in which the improved device according to my invention is
applied but generally I prefer to make them of the shape and number shown on
the accompanying two sheets of drawings.
The improvement is equally applicable to valves in which the steam &c. enters
at the ends and exhausts at the middle and to those in which the steam &c. enters
at the centre and exhausts at the ends.
The steam and exhaust laps of my improved valve may be varied according to

page_text: the periods of admission and exhaust desired, in a similar way to what is done in
ordinary piston and other valves.
When the movement is in a vertical direction the weight of my improved valve
can be balanced similarly as frequently applies in the cases of ordinary piston
valves, that is, by making the upper or lower part of larger diameter than the
other, according as the steam &c. enters at the centre or at the ends. A separate
balancing or controlling cylinder can also be fitted when such latter device is
considered more convenient.
Almost any of the many forms of packing rings and springs at present in use can
be applied to the improved valves according to my invention or they can, if so
desired be made solid without rings or springs.
The valves can also be made with bolted junk rings, for the admission of the
packings rings or springs when said arrangement is considered desirable.
My improved valve can be actuated by almost any of the many valve gears
at present in use.
For facility of description and referring to the accompanying sheet of drawings
I will assume that steam is the motive agency to be employed, without prejudice
however to the applicability of my improved valve for other gases or liquids.
Figure 1 Sheet 1 is a vertical sectional view of the valve shewn in its place
relatively to the cylinder. Figure 2 being a horizontal section taken on line C D
Figure 1.
In Sheet 2 Figure 3 is a horizontal section taken on line A B Figure 1.
Figure 4 is a horizontal section taken on line E F Sheet 1; and,
Figure 5 is a horizontal section taken on line G H Sheet 1.
Throughout the several views I is the entrance steam pipe and J J. the outlet
orifices for the exhaust steam. The positions of these pipes are of no consequence
and may either be located in the same plane as in Figure 1 or at an angle
relatively to one another as in Figure 3. Kis the valve liner with the necessary
ports or orifices formed in it. This latter is not an essential accessory of my valve
and can be dispensed with, when it is preferred that the valve shall work directly
on the cylinder barrel, L L are the cylinder ports, M is the valve, N N the
passages for the conveyance of the steam to the ports more distant from the
entrance steam pipe; OO are the passages for the conveyance of the exhaust
steam from the ports more distant from the exhaust pipes or orifices; P P arc
spaces into which the passages N N lead and which serve to allow of the entering
steam being distributed over the area of the cylinder ports L. RR are spaces
from which the passages OO lead and which collect the exhausting steam from
over the area of the cylinder ports L L.
In cases where the improved valve according to my invention is devised so as to
admit steam at the ends and exhaust at the centre, J J would then become the
entrance steam pipes and L the exhaust pipe, the valve laps being altered
accordingly.
Having now particularly described and ascertained the nature of my said inven-
tion I wish it to be understood that I do not limit myself to the precise details
herein described, or delineated but that what I claim as being novel and
original is:
First: A circular or piston valve arranged to give a simultaneous admission
of steam or other equivalent to two or more ports at each end of a cylinder
combined with a simultaneous exhaust from the same ports.
Second-The construction of a valve substantially as described which by
means of passages formed in the valves enables the combination to be attained
of the entering steam or equivalent passing to the port or ports more distant
from the entrance pipe and of the exhaust steam or equivalent passing from the
port or ports more distant from the exhaust pipe and of a suitable provision for
the distribution of the steam from these. passages to the cylinder ports and
vice-versa.

page_text: :-
Third The form of valve precisely as illustrated in the accompanying two
sheets of drawings.
Fourth-The form of valve as illustrated but with such modifications in
detail as I have referred to in the body of this Specification.
Dated this Sixth day of June 1891.
JAMES STEVENSON,
Gray's Inn Chambers,
20, High Holborn, London, W.C., Agent for Applicant.