Improvements in Packing for Piston Rods and the like.
Year: 1892

page_text: Date of Application, 29th Nov., 1892
Complete Specification Left, 29th Aug., 1893-Accepted, 30th Sept., 1893
PROVISIONAL SPECIFICATION.
Improvements in Packing for Piston Rods and the like.
I, TREVOR KEENE of 16 Ravenscroft Road, Birkenhead in the County of
Chester, Engineer, do hereby declare the nature of this invention to be as
follows: -
This invention relates to metallic packing for piston rods and the like, and the
object is to provide a cheap and effective packing which, while permitting transverse
vibration of the rod due to want of alignment between the crosshead guides and
the cylinder, will tend to support the weight of the piston so as to prevent undue
wear of the cylinder.
The packing proper consists of a long bush preferably of white metal which fits
the rod closely but not tightly; if the rod have swelled ends, this bush must of
necessity be divided longitudinally into halves and, in this case, 1 form it in two
lengths arranged so as to break joint.
The white metal bush is held in a brass sleeve, the external diameter of which is
less than the bore of the stuffing box within which it is placed, so as to permit of
the necessary lateral movement; in order to prevent the white metal bush from
being pushed through the brass sleeve by the pressure of the gland or the rod
friction, I form an internal flange on the inner end of the sleeve; partially with the
same object and partially with the object of closing the bush as it wears and
facilitating its withdrawal from the sleeve, it is advisable to taper the latter
internally.
I provide an inner gland which fits the rod and enters the sleeve for a short
length; its end which abuts against the white metal bush is chamfered so as to tend
to nip the latter against the rod. If the rod have swelled ends, this gland is made
in two parts fitting one within the other, the outer one being sufficiently large in
the bore to pass over the rod end and the inner one being split longitudinally in
halves and flanged to receive the thrust from the outer portion a spiral spring
under compression may be interposed between the end of the outer and the flange
of the inner portion, for a purpose to be hereinafter explained.
The brass sleeve and the inner gland are respectively located endwise by a collar
bush and an outer gland, the latter being provided with means for drawing it
towards the stuffing box to take up wear. The collar bush and the outer gland are
each large enough in the bore to stand well clear of the rod as they are not capable
of any lateral movement. The bearing surfaces between the sleeve and collar bush
and between the inner and outer gland are respectively made portions of concentric
spheres struck from a centre corresponding with about the mean position of the
piston, so that while the packing can move laterally in the stuffing box to accommodate
the rod it can only do so by radiating about this centre and in this way the packing
tends to support the weight of the piston.
In order to maintain a greater pressure between the spherical bearing surfaces
than that between the inner gland and the white metal bush, I fit a spiral spring
under compression between an external flange of the sleeve and a corresponding
external flange of the inner gland; the object of the spring herein before referred
to, interposed between the end of the outer part of the inner gland and the flange
of the inner portion thereof, is to mitigate the pressures on the end of the white
metal bush and on the spherical bearing surfaces, should the outer gland be set up
unduly in tightening the packing.
Dated this Twenty-eighth day of November 1892.
SLOAN & LLOYD BARNES,
Castle Chambers, 26, Castle Street, Liverpool,
Agents for the Applicant.

page_text: COMPLETE SPECIFICATION.“
Improvements in Packing for Piston Rods and the like.
1, TREVOR KEENE of 16 Ravenscroft Road. Birkenhead, in the County of
Chester, 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
n and by the following statement :-
This invention relates to metallic packing for piston rods and the like, and the
object is to provide a cheap and effective packing which, while permitting transverse
vibration of the rod due to want of alignment between the cross-head guides and
the cylinder, will tend to support the weight of the piston and rod so as to prevent
undue wear of the cylinder.
In the accompanying drawings which illustrate my invention,
Fig. I is a sectional elevation on the line B B of Fig. II of the packing applied
to a rod with a swelled end, the upper half of Fig. II is a half sectional elevation
on A. A. of Fig. I and the lower part of Fig. II. is a half end view, the piston rod
being.removed.
Figs. III and IV are analogous views to Figs. I and II and illustrate an
arrangement of the packing having an additional interposed spring.
Throughout the drawings similar parts are indicated by the same reference
figures, and in the case of sections the direction in which they are viewed is
indicated by the arrow heads placed adjacent to the letters denoting the plane of
section.
i
The packing proper consists of a long bush 1, preferably of white metal, which
fits the rod 2 closely but not tightly when the rod has a swelled end as shown this
bush must of necessity be divided into halves and, in this case, I form it in two
lengths and 1' arranged so as to break joint.
The white-metal bush is held in a brass sleeve 3, the external diameter of which
is less than the bore of the stuffing box 4 within which it is placed, so as to permit
of the necessary lateral movement; in order to prevent the bush 1 being pushed
through the sleeve 3, I form the internal flange 5 on the inner end of the sleeve;
partially with the same object and partially with the object of closing the bush 1
and facilitating its withdrawal from the sleeve, it is advisable to taper the sleeve
internally as shown.
I provide an inner gland which fits the rod 2 and enters the sleeve 3 for a short
length, which gland, when the rod has a swelled end is made in two parts 6 and 7
the part 6 being split to pass over the swelled end and the part 7 being in one
piece and fitting over the inner part; the end of the latter and that of the bush 1'
fitting against it is chamfered so as to tend to nip the white metal against the rod.
A spiral spring 8 may be interposed between 6 and 7 as shown in Figs. III
and IV for a purpose explained when these figures are referred to.
The sleeve 3 and the gland are respectively located endwise by a collar bush 9
and an outer gland 10 which latter in the arrangement shown is made adjustable by
being screwed in the fixing 11 bolted to the stuffing box by the gland studs; it
may however be fixed or made adjustable in any other convenient way. The
: collar bush 9 and outer gland 10 are large enough in the bore to stand well clear
. of the rod.
The bearing surfaces between the sleeve 3 and collar bush 9 and between the
outer gland 10 and the gland 7 are made portions of concentric spheres (indicated
by the dotted lines) struck from a centre corresponding with about the mean
position of the piston, so that while the packing can move laterally in the stuffing
box to accommodate the rod it can only do so by radiating about this centre and
in this way the packing tends to support the weight of the piston and the piston rod.

page_text: In order to maintain a definite constant pressure between the spherical bearing
surfaces greater than that between the white-metal bush 1 and the gland 6 1 fit a
spiral spring 12 under compression between the gland 7 and sleeve 3 and I find this.
construction of advantage in the following way ;-
When the steam from the cylinder leaks to a small extent past the spherical joint
between the collar bush 9 and sleeve 3 it is trapped in the annular space between
the latter and the stuffing box and being wire drawn its pressure is insufficient to.
pass the spherical joint between the glands 7 and 10; when however its pressure
rises it assists the spring 12 in forcing the sleeve 3 against the collar bush and
prevents a further escape of steam between these two.
The action in this respect somewhat resembles that of a steam trap or reducing
valve and as a result the compression of the spring 12 may be less than that
necessary to so press together the spherical bearing surfaces as to entirely prevent
any escape of steam between 3 and 9 when the engine is starting, at which time the
tendency to escape is greatest, this tendency being less when the engine is running
I find this
owing to the rapid alternation of admission and exhaust of steam.
feature of special advantage in locomotive packings.
A drain cock may be fitted to allow any water that may accumulate in the
annular space to escape.
Referring now to Figs. III and IV it will be seen that in the arrangement there
illustrated a spring 8 is interposed between 6 and 7 the object being to prevent
undue nipping pressure being brought to. bear on the white-metal bush as a result of
careless adjustment of the gland 10, or the gland 10 may be fixed as the adjustment
may be dispensed with.
In this arrangement the sleeve 3 is prolonged at 3¹ so as to separate the two-
springs.
It will be noted that in each of the constructions described it is possible to use a
very long white-metal bush which I find to be of considerable advantage.
I am aware that a sleeve such as 3 has been used to carry a white-metal bush
and that interposed springs have been used in metallic packings and to such I make-
no broad claim.
Having now particularly described and ascertained the nature of my said inveu-
tion, and in what manner the same is to be performed, I declare that what I
claim is ;-
1. The herein described improvement in metallic packing for piston rods and the
like, which consists in locating the packing between two concentric spherical
bearing surfaces, struck from a point lying between the extreme positions of the
piston, substantially as and for the purpose herein set forth.
2. In metallic packing for piston rods and the like, in combination, a sleeve
supporting an inner bush and provided with a gland adapted to set up the said bush,
a spring interposed between the said sleeve and gland, one end of the said sleeve-
and the opposite end of the gland being supported by two concentric spherical
bearing surfaces struck from a point lying between the extreme positions of the-
piston, substantially as described and illustrated.
3. In metallic packing for piston rods and the like, in combination, a sleeve 3,.
split inner bushes 1 and 1' arranged to break joint, a gland formed in parts 6 and 7
and an interposed spring 12, one end of the sleeve 3 and the part 7 of the gland.
being supported respectively by a fixed and an adjustable bearing surface, said
surfaces being portions of concentric spheres, substantially as described and.
illustrated.
4. In metallic packing of the kind herein set forth, the use of the interposed.
spring 8, substantially as and for the purpose described..
5. The combination and arrangement of parts forming the improved packing for
piston rods and the like, substantially as described and illustrated with reference
to Figs. I and II.
6. The combination and arrangement of parts forming the improved packing for

page_text: piston rods and the like, substantially as described and illustrated with reference
to Figs. II and IV.
Dated this 28th day of August 1893.
SLOAN & LLOYD BARNES,
Castle Chambers, 26, Castle Street, Liverpool,
Agents for the Applicant.