Improvements in Metallic Pistons, Piston Valves, and Pump Buckets.
Year: 1885

page_text: Improvements in Metallic Pistons, Piston Valves, and Pump
Buckets.
I, JOHN WATTS of Broadweir Engine Works, in the City and County of
Bristol, Engineer do hereby declare the nature of my said Invention for
"IMPROVEMENTS IN METALLIC PISTONS, PISTON VALVES AND PUMP-BUCKETS" to
be as follows: —
My Invention has for its object to so construct metallic pistons, piston valves
and pump-buckets that they are maintained in good contact with the cylinder in
which they work and expand in a practically true circle so as not to wear the
cylinder out of shape; I will describe my Invention with reference to a piston for
a steam cylinder from which its general application will be readily understood.
According to my Invention I make each member of the piston of a metal ring
having loops or connecting pieces of metal on the internal side I divide the ring at.
the parts between where the loops or connecting pieces join the ring or where they
merge into or become part of the ring.
This cutting removes a part of the metal and allows the ring to be compressed
and turned to its working diameter it afterwards being released. Where the rings
are used for building up pistons in order to prevent leakage I preferably form loops
or connecting pieces at parts between and alternating with each loop or connecting
piece and severed part of the ring as herein before described the parts of the ring
where these intervening or alternating loops or connecting pieces occur not being
severed. When the rings are placed together the loops at the undivided part of
the one ring are placed opposite the loops at the divided part of the adjacent ring
or rings so as to prevent a passage or leakage from side to side of the piston. The
ring or rings formed as described is or are provided with covers or junk rings at
the upper and lower sides and are or may be operated in the same manner as
ordinary pistons or the like are operated.

page_text: COMPLETE SPECIFICATION.
Improvements in Metallic Pistons, Piston Valves, and Pump
Buckets.
I JOHN WATTS of Broad Weir Engine Works in the City and County of
Bristol 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 has for its object to so construct the packing of metallic pistons
piston valves and pump buckets that the said pistons piston valves or pump
buckets are maintained in good contact with the cylinder in which they work and
preferably also so that the bearing parts or packings expand in a practically true
circle or much more nearly so than has hitherto been the case with pistons piston
valves and pump buckets having packings consisting of divided or split rings, from
which it results that the cylinder is not worn out of shape or is kept much more
truly in shape than is the case with cylinders in which are employed ordinary
pistons piston valves or pump buckets with the description of packing hereinbefore
mentioned. I will describe my Invention with reference to a piston for a steam
cylinder from which its application to pistons piston valves and pump buckets
generally will be readily understood.
According to my Invention I make each ring or component member of the
periphery or bearing surface or packing of the piston of a metal ring divided in
one or in more than one place and having a loop or connecting piece or loops or
connecting pieces of metal on the internal side tending to press the parts of the ring
outwards. I prefer to cast the ring with the loop or connecting piece or loops or
connecting pieces thereon and then to cut or divide the ring at the part or parts
between where the loop or connecting piece or loops or connecting pieces joins or
join the ring or where it or they merge into or become part of the ring This
cutting or dividing removes a part of the metal and allows the ring to be
compressed and turned to its working diameter, it afterwards being released
Where a number of these rings is used for building up pistons, in order to prevent
leakage through the divided portions of the rings, I place the divided part of one
ring opposite an undivided part of the adjacent ring or rings preferably forming
loops or connecting pieces at parts between and alternating with each loop or
connecting piece and severed part of the rings as hereinbefore described, the parts
of the rings where these intervening or alternating loops or connecting pieces occur
not being severed. When the rings so formed are placed together the loops at the
undivided part of the one ring are placed opposite the loops at the divided part of
the adjacent ring or rings so as to prevent passage or leakage of fluid from side to
side of the piston. The ring or rings formed as described is or are provided with
covers or junk rings at the upper and lower sides and are or may be operated in
the same manner as ordinary pistons or the like are operated. I do not limit
myself to the use of any particular number of rings with each piston, piston valve,
or pump bucket, as one or more may be used as may be required in any particular
The division of the ring or rings at one place only and the provision of a
case.

page_text: loop or its equivalent at that part gives a greatly improved outwardly springing
action, whilst the division of the ring or rings at more than one place gives an
expansion of the ring or rings in a true or practically true circle or much more
nearly approaching a true circle than is the case with the ring or rings divided in
only one place.
And in order that my said Invention may be fully understood I shall now
proceed more particularly to describe the same and for that purpose shall refer to
the several figures on the annexed Sheets of drawings the same letters of reference
indicating corresponding parts in all the figures.
Figure 1 shews one of the simple packing rings constructed according to my
Invention, E being the ring, divided at e and provided with a loop & connecting
the divided ends of the ring so as to have an outwardly springing action upɔn
them.
The loop or connecting piece G is shewn as being cast in one with the ring E, as
I find a convenient mode of manufacture is to cast the ring with the loop or loops
in one therewith and then cut the metal of the ring and afterwards compress the
ring and turn it to its working diameter as hereinbefore described, but I do not
limit myself to this particular method of making the rings as the loops or connecting
pieces GG may be formed separately from the ring E and be attached thereto by
bolting or rivetting or otherwise, or part of the connecting piece or loop G may be
formed or fixed on one part of the ring and another part of the loop or connecting
piece be formed or fixed on the adjacent part of the ring and the two parts of the
loop or connecting piece be bolted rivetted or otherwise fastened together.
Figure 2 is a transverse Section and Figure 3 is a longitudinal Section of a piston
provided with two rings according to my Invention. The portion of the cylinder
shewn is marked A-B is the piston rod, and C is the piston body between which
and the junk ring D, the rings E are secured by the bolts F. Each ring E is, (in
this example,) divided at e, e, in more than one place and the parts are connected
by loops or connecting pieces G, G, which act as springs to force the parts of the
ring outwards against the interior of the cylinder A
The rings I have shewn are of a channel form in Section but the section may of
course be varied as desired and as before stated there may be one ring or more
than one ring for each piston. Midway between each of the divisions in the rings
there are formed loops H H so that when more than one ring is used when the
rings are placed together as shewn in the drawings a closure is formed to prevent
steam or other fluid leaking past the piston through the divided parts of the rings
at e. The rings when several are used are arranged as shewn clearly in the
Drawing so that the divided parts and the corresponding loops or connecting pieces
of one ring are over the parts which are not divided but which have corresponding
loops or connecting pieces.
In Figures 2 and 3 the body of the piston is shewn recessed to accommodate the
loops but this is not essential. Figures 4 and 5 are similar views to those shewn
in Figures 2 and 3 in which the piston body is not so recessed and in which a
much larger number of divided parts and connecting and intermediate loops are
shewn The parts in these Figures are marked with the same letters of reference
as are used to indicate similar parts in the preceding Figures. In Figure 6 I have
shewn four rings together with the divided parts of the two outer rings situated in
the same longitudinal line, the divided parts of the two mid rings being situated
in other longitudinal lines midway between the longitudinal lines in which the
divided parts of the outer rings occur. I have shewn in this Figure 6 in the
Drawing a Spring h which bears upon the parts h² which are formed on the two
inner rings. Several of these springs are used at equidistant portions of the rings
to press the inner rings into close contact with the outer rings and the outer rings
into close contact with the juuk rings, but it is to be understood that these springs
are not essential to my Invention It will be evident that the special construction
or formation of the parts as shewn in the Drawing may be considerably varied
without departing from the nature of my Invention As an example of a variation

page_text: I have shewn at Figure 7 a ring divided at more than one place but with only one
loop. This Figure serves to illustrate not only that it is possible to divide the ring
at more than one place with but one connecting loop but also that the loop may take
any convenient form-It is here shewn as being much enlarged and made con-
centric with the packing ring E. Figure 8 shews a modification wherein the
equivalent of the loops herein before described is provided by means of an inner
ring E³ with connecting pieces arms webs or strips connecting thereto each divided
part of the ring E so that the said connecting pieces arms webs or strips serves as
outwardly pressing springs to keep the rings in close contact with the cylinder
with the piston valve or pump bucket of which a ring or rings thus constructed is
or are used-The precise variations which I have illustrated in the drawing are not
necessarily those to which I limit myself but I have illustrated them as the best
means with which I am acquainted for carrying my Invention into effect.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed I declare that what
I claim is
First. The manufacture for and use in pistons, piston valves, and pump buckets,
of a packing ring or packing rings, each such ring being divided in one or in more
than one place, and being provided with a loop or loops or equivalent means for
connecting the divided parts, and pressing the ring outwards substantially as
heroinbefore described and illustrated with reference to the accompanying
drawings.
Second. The manufacture for, and use in pistons, piston valves, and pump
buckets, of a packing ring or packing rings, each ring being divided in more than
one place, each of the places where the ring or rings is or are divided being
provided with a loop or equivalent means for connecting the adjacent divided parts
and pressing the ring or rings outwards substantially as and for the purposes
herein before described and illustrated with reference to the accompanying
drawings.
Third. The manufacture for and use in pistons piston valves and pump buckets
of divided packing rings provided with a loop or loops or connecting pieces joining
the adjacent divided parts of the rings, and alternating with corresponding loops or
connecting pieces at unsevered parts of the rings, which when the rings are
superposed or built upon the piston, piston valve, or pump bucket give a joint to
prevent leakage substantially as herein before described and illustrated with reference
to the accompanying drawings.
Fourth. The several arrangements and combinations of parts constituting the
packing rings for pistons, piston valves, and pump buckets, and the packed pistons
piston valves, and pump buckets, herein before described and illustrated in the
several Figures of the accompanying drawings.
Dated this Seventh day of October 1885.