Improvements in Pumps for Pumping or Compressing Gases or Vapors.
Year: 1893

page_text: Date of Application, 19th Apr., 1893
Complete Specification Left, 18th Jan., 1894-Accepted, 24th Feb., 1894
PROVISIONAL SPECIFICATION.
Improvements in Pumps for Pumping or Compressing Gases or
Vapors.
I, THOMAS ROBERTS MURRAY, of The Crown Iron Works, North Woodside
Road, Glasgow, in the County. of Lanark, North Britain, Engineer, do hereby
declare the nature of this invention to be as follows, that is to say :-
My said invention has for its object to improve the action and increase the
efficiency of pumps for pumping or compressing gases or vapors, by employing
devices applicable to double acting pumps and which more completely than
heretofore expel the gas or vapor at each delivery stroke and thereby avoid loss
that would be caused by the re-expansion of any unexpelled gas or vapor.
In carrying out the invention a proper quantity of a suitable oil or liquid is
injected into each end of the cylinder for every stroke, this liquid being sufficient
to expel in advance of itself all the gas or vapor and to fill the end of the
cylinder and the passages or clearances between the cylinder and the valves. The
desired action is effected easily at the upper end of the cylinder, and it is with
the lower end that the present improvements have principally to do. The lower
end of the cylinder is made with its internal space extending below the bottom
passages communicating with the valves, and with the bottom preferably of a
conical form. Below the piston there is fixed on it or on the piston rod a displacer
block, which, as the piston approaches the bottom of its stroke, enters the
extended cylinder space, and there dipping into the oil or liquid causes such oil or
liquid to rise round it. An indentation or recess is formed round between the
bottom of the piston and the displacer block, and holes communicate between this
recess and the bottom of the displacer block, so that when the oil or liquid is
displaced by the block, some of it rises up through the holes so as to fill the recess
and flow outwards from it, in a manner to expel the whole of the gas or vapor.
Dated this Eighteenth day of April 1893.
EDMUND HUNT,
Applicant's Agent.
Improvements in Pumps for Pumping or Compressing Gases or
Vapors.
I, THOMAS ROBERTS MURRAY, of The Crown Iron Works, North Woodside
Road, in the County of the City of Glasgow, North Britain, Engineer, 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, that is to say :-
My said invention has for its object to improve the action and increase the
efficiency of pumps for pumping or compressing gases or vapors, by employing
devices applicable to double-acting pumps and which more completely than hereto-
fore expel the gas or vapor at each delivery stroke and thereby avoid loss that
would be caused by the re-expansion of any unexpelled gas or vapor.
In carrying out the invention a proper quantity of a suitable oil or liquid is
injected into each end of the cylinder for every stroke, this liquid being sufficient
to expel in advance of itself, all the gas or vapor and to fill the end of the cylinder

page_text: and the passages or clearances between the cylinder and the valves. The desired.
action is effected easily at the upper end of the cylinder, and it is with the
lower end that the present improvements have principally to do, as they consist
chiefly of a particular formation of the bottom part of the cylinder and the
provision of a displacer block (hereinafter described) on the piston to cause the
injected oil to act as desired.
And in order that my said invention and the manner of performing the same
may be properly understood I hereunto append a sheet of explanatory drawings,
to be hereinafter referred to, and showing a pump as made with my improvements.
Figure, 1, of the drawings is a sectional elevation of my improved pump, and
Figure, 2, is a vertical section as at right angles to Figure, 1. In these drawings
the same reference letters are used to mark the same or like parts wherever they
are repeated.
The oil or other liquid is injected into the upper end of the cylinder, A, through
a passage, B, and into the lower end through a passage, C, these passages being
provided with check valves. The lower end of the cylinder, A, is made with its
internal space extending below the bottom passages, D. communicating with the
inlet and delivery valves, E, and with the bottom preferably of a conical form.
Below the piston, F, there is formed in a piece with the piston rod, G (or it
might be formed on the piston) a displacer block, H, which as the piston
approaches the bottom of its stroke, enters the extended cylinder space and there
dipping into the oil or liquid causes such oil or liquid to rise round it. An
indentation or recess, J, is formed round between the bottom of the piston, F, and
the displacer block, H, and holes, K, communicate between this recess and the
bottom of the displacer block, so that when the oil or liquid is displaced by the
block some of it rises up through the holes so as to fill the recess and flow
outwards from it in a manner to expel the whole of the gas or vapor.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :
In pumps for pumping or compressing gases or vapors, employing a vertical
pump cylinder having its internal space extended below the bottom valve passages,
combined with a piston having formed or fixed on it or on its rod a counter part
displacer block made with an encircling recess between it and the piston which
recess communicates by holes with the bottom of the displacer block substantially
as and for the purposes hereinbefore described.
Dated this Seventeenth day of January 1894.
EDMUND HUNT,
Applicant's Agent.