IMPROVEMENTS IN DIRECT- ACTING ENGINES FOR STEAM PUMPS
Year: 1874

page_text: LETTERS PATENT to Jonathan Pickering, of Stockton-on-Tees, in the
County of Durham, for the Invention of "IMPROVEMENTS IN DIRECT-
ACTING ENGINES FOR STEAM PUMPS."
Sealed the 19th May 1874, and dated the 14th March 1874.
PROVISIONAL SPECIFICATION left by the said Jonathan Pickering
at the Office of the Commissioners of Patents, with his Petition,
on the 14th March 1874.
I, JONATHAN PICKERING, of Stockton-on-Tees, in the County of
Durham, do hereby declare the nature of the said Invention for "IM-
PROVEMENTS IN DIRECT-ACTING ENGINES FOR STEAM PUMPS," to be as follows:-
-
This Invention relates to certain improvements in the cylinder slide
valve and steam ways.
One part of the improvement consists in the cylinder having double
steam ways, one the ordinary and the other the auxiliary.
Another part of the improvement provides an arrangement for
moving the slide valve by steam pressure exerted at the end of each

page_text: stroke of the piston without the use of tappets or levers.
The arrange-
ment is made thus: Near the end of the stroke of the piston or the
cylinder, already described, is an auxiliary steam way passing through
the cylinder and opening into the end of the slide valve. As soon as the
piston has passed over the opening steam is admitted into the slide valve
and steam pressure being thus exerted against the end it is forced to the
opposite end of its traverse.
A supplementary steam way is open to carry off the waste steam from.
the slide valve end into the exhaust pipe. Thus the pressure on the
slide valve is withdrawn, and space is left for its return. The steam
having access to the other side of piston through steam ways similar to
those usually provided in steam cylinders will be forced to the other end
of it and will pass over the auxiliary steam way as it approaches the end
of the stroke, thus giving continuous reciprocating action to the slide
valve and piston automatically by the opening and shutting of the
ordinary and the auxiliary steam ports. The inlet to the slide valve is
divided into two parts, between which is a pin screwed into a slot to
prevent the slide valve turning round.
The said Invention consists, further, in an arrangement for altering
the position of the auxiliary steam way, which is made to receive a tube, is a
passed through a stuffing box, and has holes or ports through the cylinder
at varying distances from each end, this forming additional steamways.
This tube when moved round will open and shut the passages for steam
into the slide valve end and give a shorter or longer stroke to the piston,
according to the distance of the port holes from the ends of the cylinder. 2
Again, by this arrangement the piston is prevented from striking the
end of the cylinder. The central or ordinary tramways are similar to
those usually provided in steam cylinders.
This Invention not only relates to the engines herein described being
applied to a pump, but is applicable also to a blowing engine to give a
reciprocating motion without the use of gearing cranks or levers.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Jonathan Pickering in the Great Seal Patent Office
on the 31st August 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, Jonathan
PICKERING, of Stockton-on-Tees, in the County of Durham, send
greeting.
of
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fourteenth day of March, in the year
our Lord One thousand eight hundred and seventy-four, in the thirty-
seventh year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Jonathan Pickering, Her special licence
that I, the said Jonathan Pickering, my executors, administrators, and
assigns, or such others as I, the said Jonathan Pickering, my executors,
administrators, and assigns, should at any time agree with, and no others,
from time to time and at all times thereafter during the term therein
expressed, should and lawfully might make, use, exercise, and vend,
within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN DIRECT-
ACTING ENGINES FOR STEAM PUMPS," upon the condition (amongst others)
that I, the said Jonathan Pickering, my executors or administrators, by
an instrument in writing under my, or their, or one of their hands and
seals, should particularly describe and ascertain the nature of the said
Invention, and in what manner the same was to be performed, and
cause the same to be filed in the Great Seal Patent Office within six
calendar months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said Jonathan Pickering, do hereby
declare the nature of my said Invention, and in what manner the
same is to be performed, to be particularly described and ascertained in
and by the following statement:-
This Invention relates to certain improvements in the cylinder slide
valve and steam ways.
One part of the improvement consists in the cylinder having double
steam ways, one the ordinary and the other the auxiliary...
"Another part of the improvement provides an arrangement for moving
the slide valve by steam pressure exerted at the end of each stroke of
the piston without the use of tappets or levers. The arrangement is

page_text: made thus: Near the end of the stroke of the piston, on the cylinder
already described, is an auxiliary steam way passing through the cylinder
and opening into the end of the slide valve. As soon as the piston has
passed over the opening steam is admitted into the slide valve, and
steam pressure being thus exerted against the end it is forced to the
opposite end of its traverse.
A supplementary steam way is open to carry off the waste steam from
the slide valve end into the exhaust pipe. Thus the pressure on the
slide valve is withdrawn and space is left for its return. The steam
having access to the other side of piston through steam ways similar to
those usually provided in steam cylinders will be forced to the other end
of it and will pass over the auxiliary steamway as it approaches the end
of the stroke, thus giving continuous reciprocating action to the slidė
valve and piston automatically by the opening and shutting of the
ordinary and the auxiliary steam ports. The inlet to the slide valve is
divided into two parts, between which is a pin screwed into a slot to
prevent the slide valve turning round.
The said Invention consists, further, in an arrangement for altering
the position of the auxiliary steam way which is made to receive a tube,
is passed through a stuffing box, and has holes or ports through the
cylinder at varying distances from each end, thus forming additional
steam ways.
This tube when moved round will open and shut the
passages for steam into the slide valve end and give a shorter or longer
stroke to the piston, according to the distance of the port holes from the
ends of the cylinder. Again, by this arrangement the piston is prevented
from striking the end of the cylinder. The central or ordinary steam
ways are similar to those usually provided in steam cylinders.
This Invention not only relates to the engines berein described being
applied to a pump, but is applicable also to a blowing engine to give
reciprocating motion without the use of gearing cranks or levers.
Having explained the nature of my Invention I will proceed to
describe, with reference to the accompanying Drawings, the manner in
which the same is to be performed.
Figure 1 represents a longitudinal section of cylinder shewing piston,
slide valve, and steam ways; Fig. 2 is an end section through a, b;
Figure 3 is a section through c, d. The same letters indicate the same
parts in the whole of the Figures,

page_text: A is the cylinder; B is the piston; L, M, are the auxiliary steam ways.
The position of the piston is shewn at the left, the steam passing into
the auxiliary steam way M will force the slide valve to the left, opening
the steam passage for exhaust O, E, at the same time admitting through
the inlet I to K, N, D, to give another stroke of the piston. When tho
piston is approaching the end of the stroke it will pass over the auxiliary
steam way L, changing again the position of the slide valve to the other
cnd of its traverse. The slide valve C is shewn with an oblong opening
P, P, to admit the steam to the annular recesses K, K, to pass through
the under side of slide valve to cylinder at O and N alternately as the
slide valve is reversed. I is the inlet; E is the exhaust. The slide
valve is kept in proper position with a pin fixed into one of the steam
chest covers, as shewn in section Figures 1 and 3. The connection to a
pump is partly shewn, which will be readily understood. The cylinder
is about double the length of the stroke, the piston is therefore half
the length of the cylinder; the slide valve is circular and nearly equi-
librium, having a little more area for steam pressure downwards to keep
it steam-tight on the face, the openings P, P, being nearer the top. The
slide valve is moved to and fro by steam pressure against the ends,
admitted through the auxiliary steam ways; the piston acting as a valve
at the termination of each stroke uncovers the inlet thereto, the motion
is thus given to the slide valve before the piston reaches the ends of the
cylinder.
The steam ways to the piston arc of the usual kind in the steam
engines. The auxiliary steam ways pass round on either side of the
cylinder; G, H, by preference are near the bottom, in order that the
piston's weight may keep the openings L and M steam-tight.
Having explained and described the nature of my Invention, and how
the same is to be performed, I claim, the combination of these parts as
shewn in Drawings and Specification herein set forth.
In witness whereof, I, the said Jonathan Pickering, have hereunto
set my hand and seal, this Twenty-fifth day of August, in the
year of our Lord One thousand eight hundred and seventy-four.