Improvements in Metallic Pistons.
Year: 1893

page_text: Date of Application, 2nd May, 1893
Complete Specification Left, 1st Feb., 1894-Accepted, 24th Feb., 1894
PROVISIONAL SPECIFICATION.
Improvements in Metallic Pistons.
We THOMAS SHEPHERD of Union Works Charles Street Manchester
Engineer, MARK OLIVER of Factory Lane Oldfeld Road, Salford Merchant,
and JOSEPH GORDON POPE of Wilbraham Road Fallowfield, Manchester
Engineer all in the County of Lancaster, do hereby declare the nature of this
invention to be as follows :-
This invention relates to an invention for which Letters Patent No. 13954 were
applied for on the Second day of August 1892 by Thomas Shepherd and Mark
Oliver, two of the above named petitioners and consists principally in improvements
in the construction of the packing rings themselves and in their combination with
the metallic pistons.
In the first place instead of having plain rings of the U, V or other trough-like
section, simply, we propose to give a greater elasticity to such rings by cutting
away certain portions of the same at the base of the U or V, leaving intermediate
portions only connecting the two sides together, whereby the elasticity of the rings
is greatly increased. These cut-away portions may be so arranged as to be con-
centric with the exterior of the ring, but we prefer to make the same excentric and
so that the thickest part of the metal shall be opposite to the point where the ring
is split or divided so as to allow it to maintain a perfect circle when expanded.
Or, the same effect may be produced by cutting radial saw-gates or notches
through the inner part of the rings, such saw-gates or notches being shallowest at
the point opposite to where the rings are split or cut and becoming gradually
deeper towards the place where they are split. Or, it may be produced by drilling
or forming holes of a graduated size through the sides of the U or V, the largest
holes being nearest to the ends of the split rings and the smallest at the point
opposite to the cut or split.
.
Sometimes instead of making the rings of a trough-like section as aforesaid we
make them like washers of a dished form so that when two of them are placed
together back to back, they make a single Ụ or V section divided at the base, or
we can place four of these together so as to form a W section.
Secondly, instead of using these rings as packing rings we propose to use them
as spring rings only, placing them inside the ordinary split packing rings which
are of an angle section and present a more extended wearing surface.
Thirdly, instead of making the body of the piston in two halves as in our original
Specification No. 13954" before referred to we make the piston of a single block
and secure the rings thereon by means of a removable "junk-ring," in which case
the packing discs or plates are placed between the block and the "junk-ring."
Dated this 1st day of May 1893.
GEO. DAVIES & SON,
4, St. Ann's Square, Manchester, Agents for the Applicants.

page_text: Improvements in Metallic Pistons.
We THOMAS SHEPHERD of Union Works, Charles Street, Manchester,
Engineer, MARK OLIVER of Factory Lane, Oldfield Road, Salford, Merchant, and
JOSEPH GORDON POPE of Wilbraham Road, Fallowfield, Manchester Engineer
all in the County of Lancaster, 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 :-
This invention relates to an invention for which Letters Patent No. 13945 were
applied for on the 2nd day of August 1892 by Thomas Shepherd and Mark Oliver
(two of the above named applicants) and consists principally of improvements in
the construction of the packing rings themselves and in their combination with
metallic pistons.
The nature of our said invention and the manner in which the same is to be
performed or carried into practical effect will be readily understood on reference to
the sheet of drawings hereunto annexed and the following explanation thereof.
Fig. 1 on the drawings is a face view; Fig. 2 an edge view, and Fig. 3 a section
of one of our packing rings made according to the Specification No. 13954-1892,
above referred to; Fig. 4 is a section of a steam engine cylinder shewing the com-
bination of two of these rings with the metallic piston made with a solid body and
a junk ring; Fig. 5 is a sectional view of a metallic piston showing two of our
present improved rings (not in section) applied thereto in combination with the
ordinary form of packing ring, our improved rings serving in this case only as
spring rings for expanding the ordinary packing rings.
Figs. 6, 7, 8 and 9 are face views of modified forms of our improved piston
rings; Fig. 10, is a section and Fig. 11 an edge view of Fig. 8, Fig. 12 an edge
view of Fig. 9, and Figs. 13 to 18 inclusive are sections of various other modified
forms of rings.
In the first place instead of having plain rings of the U, V, or other similar
trough-like section, we propose to give a greater elasticity to such rings by cutting
away certain portions of the same at the base of the U or V, as shewn at a
Figs. 8, 9, 10, 11 and 12; leaving intermediate portions b only connecting the two
sides of the U or V together, whereby the elasticity of the rings is greatly
increased. These cut-away portions a may be so arranged as to be concentric with
the exterior of the ring as shewn at Fig. 9, but we prefer to make the same
eccentric as shewn at Fig. 8, so that the thickest part of the metal shall be opposite
to the point where the ring is split or divided so as to allow it to maintain a perfect
circle when expanded.
Or, the same effect may be produced by drilling or forming holes c of a graduated
size through the sides of the U or V, the largest holes being nearest the ends of
the split rings and the smallest at the point opposite to the cut or split as shewn at
Fig. 6; or, by cutting graduated radial saw-gates or notches d through the inner
part of the rings as shewn at Fig. 7, such saw gates or notches being shallowest at
the point opposite to where the rings are split or cut.
Sometimes, instead of making the rings of a trough-like section as aforesaid, we
make them like washers of a dished form so that when two of them are placed
together back to back as shewn at Fig. 14, they make a single U or V section
divided at the base; or, we can place four of these dished washers together so as
to form a W section.
Instead of using these rings as packing rings, we propose to use them sometimes
as spring rings only, placing them inside the ordinary split packing. rings e which
are of an shaped section and present a more extended wearing surface as shewn
in the sectional view Fig. 5.

page_text: Instead of making the body of the piston in two halves joined in the centre (as
described in our original Specification No. 13954 of 1892 before referred to) we
make the piston of one single block (Figs. 4 and 5) and secure the rings thereon
by means of a removable "junk ring" g, in which case the packing discs or plates h
are placed between the block f and the "junk" ring g.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed we declare that what
we claim is :-
1. Metallic packing rings for pistons of a more or less U or V shape in section
and having certain portions of the same at the base of the U or V cut away, so as
to give greater elasticity to such rings substantially as herein described.
2. Metallic packing rings for pistons of a more or less U or V shape in section
and having graduated notches or saw-gates, cut in the base of the same for the
same purpose substantially as herein described.
3. Metallic packing rings for pistons of a more or less U or V shape in section,
and having graduated holes drilled or formed in the sides thereof for the same
purpose substantially as herein described.
4. Metallic packing rings for pistons formed like dished washers, so that by placing
two of them back to back, they will form a more or less U or V shaped section or
by placing four together they will form a section of a W shape substantially as
herein described.
5. In metallic pistons the combination of metallic spring rings of more or less
U or V shaped section, or dished as hereinbefore described, with the ordinary
L section packing rings.
6. In metallic pistons fitted with rings more or less U or V shaped section or
dished as herein before described the combination of a solid piston body with a
removable "junk" ring and packing discs or plates, placed between the block and
the "junk" ring.
Dated thig 31at day of Janu 180
GEO. DAVIES & SON,
4, St. Ann's Square, Manchester, Agents for the Applicants.