Improvements in Piston Packings.
Year: 1894

page_text: Date of Application, 8.h Sept., 1894
Complete Specification Left, 17th Dec., 1894-Accepted, 23rd Mar., 1895
Improvements in Piston Packings.
We, RICHARD FLETCHER CHRISTMAS TONGE, and JOSEPH BUTTERWORTH,
both of Withington Street, Pendleton in the County of Lancaster, Engineers do
hereby declare the nature of this invention to be as follows:-
Our invention relates to that form of piston packing which is usually kept tight
with coach springs. The latter are found in practice to not have sufficient elasticity
to keep the rings continuously steam-tight and have to be packed out at intervals as
the ring wears. In order to remedy this we propose to make the spring of a wave
form, and construct it of steel or other elastic metal, wire, or rods, the space between
the corrugations or waves being about equal to the diameter of the wire used, and
the depth of the corrugations or waves being about equal to the width of the ring
less the thickness of the wire forming the spring. The general form of the spring
when complete is similar to that of an ordinary coach spring, but more elastic, as it
is not only capable of bending like the latter, but can also be compressed in the
direction of its length, this latter action being utilized to follow up the ring as it
wears, and keep it steam tight until worn away. For fixing the springs in position
in the spaces provided for them behind the rings as when coach springs are used we
use a bolt with a flat hooked end fitted with a hooked shaped washer, and nut and
bent to the shape of the spring.
The apparatus acts substantially as a pulling jack & compresses the spring as the
nut on the above bolt is screwed up after being placed in position, thus the spring
can be shortened sufficiently to go in the spaces behind the rings and the bolt can
be then drawn off. In order to adapt the spring to pistons in which there are no
recesses to receive same, we propose to form recesses in the back of the rings
by casting projections at equal intervals round same, the spaces between the
projections being rather less than the length of the springs, in order to compress
the latter and cause them to react on the rings, thus developing the necessary out-
ward pressure. In cases where it is desirable to utilize old rings which have no
projections behind and also no recesses in the body of the piston or in preference to
the above method we propose to place loose pockets behind the ring each pocket
being rather shorter than the length of the springs, and the whole number of
pockets arranged so as to fill the circumferential space behind the rings.
As an alternative method we propose to fix pegs in the rings or piston body at
the same distance apart as the projections previously mentioned, or holes may be
drilled in the piston body or piston rings at the same distance apart and peg
formed on each end of the springs to fit in same, thus taking the place of the
projections previously mentioned.
Dated this Sixth day of September 1894.
R. FLETCHER C. TONGE
JOSEPH
BUTTERWORTH.

page_text: Improvements in Piston Packings.
We RICHARD FLETCHER CHRISTMAS TONGE of 25 Withington Street
Pendleton Manchester, Engineer and JOSEPH BUTTERWORTH of 23 Withington
Street Pendleton Manchester 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 :-
Our invention relates to that form of piston packing which is usually kept tight
with coach springs. The latter are found in practice to not have sufficient elasticity
to keep the rings continuously steamtight & have to be packed out at intervals
the ring wears. In order to remedy this we propose to make the spring of a wave
form, and construct it of steel or other elastic metal wire or rods, the space between
the corrugations or waves being about equal to the diameter of the wire used, and
the depth of the corrugations or waves about equal to the width of the ring less the
thickness of the wire forming the spring. The general form of the spring when
complete is similar to that of an ordinary coach spring but more elastic, as it is not
only capable of bending like the latter, but can also be compressed in the direction
of its length, this latter action being utilized to follow up the ring as it wears &
keep it steam tight until worn away. For fixing the springs in position in the
spaces provided for them behind the rings as when coach springs are used, we use a
bolt with a flat hooked, end fitted with a hooked shaped washer, and nut, and bent
to the shape of the spring. The apparatus acts substantially as a pulling jack and
compresses the spring as the nut on the above bolt is screwed up after being placed
in position, thus the spring can be shortened sufficiently to go in the spaces behind
the rings, and the bolt can be then drawn off. In order to adapt the springs to
pistons in which there are no recesses to receive same, we propose to form rece-se:
in the back of the rings by casting projections at equal intervals round same, the
spaces between the projections being rather less than the length of the springs, in
order to compress the latter & cause them to react on the rings, thus developing
the necessary outward pressure. In cases where it is desirable to utilize old rings
which have no projections behind, and also no recesses in the body of the piston, or
in preference to the above method, we propose to place loose pockets behind the
ring each pocket being rather shorter than the length of the spring, & the whole
number of pockets arranged so as to fill the circumferential space behind the rings.
As an alternative method we propose to. fix pegs in the rings or piston body at the
same distance apart, as the projections previously mentioned, or holes may be drilled
in the piston body or piston rings at the same distance apart, and pegs formed on
each end of the springs to fit in same.
In order that the invention may be more clearly understood, reference is made to
the following drawings, arranged in two sheets. In Sheet Figs. 1 & 2. give
front, and edge view respectively of the spring. Fig. 3. gives an edge view of the
spring in two positions the upper position A" being that which it would assume
when forced between the snugs "N" if not compressed by the piston ring. The
lower position "B" is the form the spring assumes when the piston ring is in its
place, the spring being thus made to alter its shape to conform with the space
available behind the rings, and consequently reacting on the piston rings, keeping
same tight against the cylinder walls & compensating for wear. Fig. 4. shows a
piston fitted with a full complement of the springs marked "S" the upper half ot
piston is shewn with ring "R" unworn while the lower half is shewn with the
ring "R" nearly worn away, thus illustrating the manner in which the springs
alter their form in following up the ring in order to keep it steam tight. In Fig. 5.
is shewn the method of forming loose pockets "P" to lie inside the ring
R"

page_text: while Fig. 6. shews loose pockets "P" arranged to lie against piston block "B."
The object of the pockets in each case being to take the place of the snugs "N" in
Fig. 3. where same are not already cast on either the rings or the block. Fig. 7.
illustrates another method of providing a substitute for the snugs N Fig. 3.
Holes are drilled in either the piston block or piston rings at a distance apart
rather less than that of the pegs "A" formed on each end of the springs "S" so
that the pegs can be forced into the holes, which latter then act in a similar manner
to the snugs
"N" Fig. 3. forming abutments against which, the spring "S" may
press in order to react on the piston ring & hold same tight against the walls of the
cylinder. Or instead of the above method pegs may be fixed in the ring or piston
block to act as abutments for the springs as described. Fig. 9. gives an elevation
of the tool consisting of a hooked bolt "B" hooked washer "W" and a wing
nut "V" by means of which the spring "S" shewn in dotted lines may be com-
pressed by screwing up the wing nut "V" until it will slide between the
snugs "N or in the pockets "P" or the holes previously described. Fig. 10. is
a plan of the bolt "B" shewing the form of the hooked end "C" and
washer "W."
"
Having thus particularly described, and ascertained the nature of our said
invention, and in what manner the saine is applied, we herewith declare that
what we claim is :-
1st. The combination of the spring "S" with the snugs "N" Figs. 3. & 4.
2nd. The combination of the spring "S" with the loose pockets "P"
Figs. 5 & 6.
3rd. The spring "S" having pegs "A" formed on each end as shown Fig. 7.
4th. The spring "S" in combination with pegs formed either inside the piston
ring or on the piston block.
5th. The tool "B" shown Figs. 9 & 10 or any similar appliance for fixing the
springs in position.
day of December 1894.
JOSEPH BUTTERWORTH.
RICHARD FLETCHER CHRISTMAS TONGE.