Year: 1888

page_text: 1, DONALD BARNS MORISON, of 8 Albion Terrace, Hartlepool, in the County of
Durham, Engineer, do hereby declare the nature of this invention to be as follows
-
My Invention relates to the lubrication of pistons for steam or other Indicators and
consists in forming a reservoir for the lubricant in the bottom, or that part, of the
piston acted on by the steam or other fluid, in such a manner that the ste im or other
Huid is in contact with the surface of the lubricant in such reservoir, and forces it to
the outer surface of the piston through suitable holes or openings
In carrying out my invention in the case of an ordinary steam engine Indicator, I
construct my improved piston as follows
-
The piston is formed of a hollow cylinder closed at the top by a disc to which the
piston-rod is attached, the bottom of the cylinder, or that part acted on by the steam
pressure is also covered by a disc, having a tube at or near its centre, which projects
into the interior of the hollow cylinder, and terminates near the disc forming the
piston top The space in the piston between the inner circumference of the cylinder
forming the piston, and the outer circumference of the projecting tube is the reservoir
for the oil or other lubricant
It will be seen that the lubricant in this reservoir is subjected to the sume pressure
as the bottom of the Indicator piston
On and around the outer surface of the piston are one or more ordinary lubricating
grooves, which are connected to the reservoir by one or more holes, the oil or other
lubricant being forced by the pressure into the groove or grooves lubricates the
surface of the piston uniformly and the pressure of the lubricant in the grooves tends
to prevent the rush of steam past, or into the grooves and so assists in keeping the
impurities carried in the steam from being forced between the piston and the Indicator
cylinder, thus causing undue friction

page_text: COMPLETE SPECIFICATION
Improvements in Pistons for Steam or other Indicators
I, DONALD BARNS MORISON, of 8 Albion Terrace Hartlepool, in the County of
Durham, 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
My Invention relates to the lubrication of pistons for Steam or other Indicators,
and consists in forming a reservoir for the lubricant in the bottoin, or that part of the
piston acted on ly the steam or other fluid, in such a manner that the steam or other
fluid is in contact with the surface of the lubricant in such reservoir, and forces it to
the outer surface of the piston through suitable holes or openings
In carrying out my invention in the case of in ordinary steain engine Indicator, I
construct my improved piston as follows
-
The piston is formed of a hollow cylinder closed at the top by a disc, to which the
piston-rod is attached, the bottom of the cylinder, or that part acted on by the steam
pre sure is also covered by a disc, having i tube at or near its centre, which projects
into the interior of the hollow cylin ler, and terminates nou the disc forming the
piston top The spice in the piston between the inner circumference of the cylinder
forming the piston, and the outer circumference of the projecting tube, is the reservoir
for the oil or other lubricant
It will be seen that the lubricant in this reservoir is subjected to the same pressure
as the bottom of the Indicator piston
On and around the outer circumference of the piston are one or more ordinary
lubricating grooves, which are connected to the reser oir by one or more holes, the oil
or other lubricant being forced by the pressure into the groove or grooves lubricates
the surface of the piston uniformly, and the pressure of the lubricant in the grooves
tends to prevent the rush of steun past or into the grooves, and so assist in keeping
the impurities carried in the stem from being forced between the piston and the
Indicator, thus causing undue friction
In order that my invention may be fully understood, I will now particularly describe
the same, with reference to the accompanying drawing
Figure I shews a method of applying my Invention to a new indicator piston, and
Figure 1 shows a method of applying the same to existing pistons
inner fice
In Figure I the metal A at the bottom of the piston has i screw thread cut on its
The bottom disc B with the tube or tubular projection C formed upon it
15 screwed into this The space D D around this projecting part and within the
piston is the reservoir for the oil or other lubricant
In Figure II the bottom disc B is secured in position by means of the screws E E
the reservo r for the lubricant being formed as in the previous case
The steam or other fluid acting upon the bottom of the piston passes freely
through Cand acts upon the surface of the lubricant in D D, the lubricant will thus
be forced through the holes F F into the groove or grooves G G and so the body

page_text: The lubricant in the groove
of the piston will be suitably and uniformly lubricated
or grooves G G will assist in keeping the impurities carried by the steam from being
forced between the piston and the cylinder of the Indicator
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 18-
(1) In pistons for steam or other indicators, the formation of a reservoir for
lubricating material in the bottom or that part, of the piston, acted upon by the steam
or other fluid, in such a manner that the steam or other fluid acts upon the surface
of the labricant and so forces it through suitable openings to the outer surface of the
piston, as hereinbefore described and explained with reference to the accompanying
drawing
(2) The particular forms of lubricating reservoir, and combination of parts forming
the same, shewn in Figures I and II