Improvements in or in connection with Metallic Packings for Piston Rods, Valve Rods, or the like.
Year: 1896

page_text: Date of Application, 11th May, 1896-Accepted, 1st Aug., 1896
Improvements in or in connection with Metallic Packings for
Piston Rods, Valve Rods, or the like.
A communication by THOMAS LISTER, of Durban, in the Colony of Natal,
Engine Fitter.
1, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of The Agency for
Foreign Patent Solicitors, 6 Lord Street, Liverpool and 6 Bank Street,
Manchester both in the County of Lancaster, 118 New Street, Birmingham in
the County of Warwick and 322 High Holborn in the County of Middlesex,
Civil 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 :-
This invention relates to metallic packings for piston rods, valve rods or the
like.
It will be understood from the following description, reference being had to
the accompanying drawing, which shows a longitudinal section of a metallic
packing applied to a piston rod, in which A is the piston rod, B the stuffing box,
C the iron giand, D gun metal gland, E metallic packing, F gun metal follower,
G spiral spring and H gun metal neck bush. Hitherto there has been nothing to
hold this neck bush H in position except the spiral spring G, the opposite end of
which presses upon the follower F. Experience has however proved that this
spiral spring is insufficient to perform the work required of it, and as a consequence
the neck bush H is liable to move backwards and forwards with every stroke of
the piston rod, resulting in constant breakages of the said neck bush. When this
breaking takes place, say on the edge of the flange nearest the inside of the
cylinder, the broken pieces fall into the cylinder, and, on the next return stroke
of the piston, they come in contact with the piston and get jammed between the
piston and cylinder cover, causing great damage by smashing either the piston or
the cylinder cover itself.
Now the present invention is designed to enable the neck bush H to be held
firmly in its proper position, so as to prevent breakage thereof with the consequent
injury to the piston or cylinder. It will therefore supply a long needed want and
fulfil the purpose which the said spiral spring has hitherto failed to supply.
In carrying the invention iuto effect the plan preferred is to insert a metal bush
or sleeve 1 or its equivalent in the intervening space between the flange on the
beck bush H and the gun metal gland D. It may be solid or split and is inserted
in place in the following manner :-In the packing of the stuffing box for a piston
rod or valve spindle, the neck bush H is first placed in position, after which the
The bush or sleeve I is
spiral spring G is inserted, followed by the follower F.
then put in, and placed flush up to the flange of the neck bush H, after which the
metallic packing rings E are put on the rod and the whole is secured by the
glands D and C. The various parts are so arranged that the bush or sleeve I will
firmly hold the neck bush H in position and prevent it from moving by the action
of the piston rod, valve rod or even the pressure of steam in the cylinder, and thus
breakages with their consequence of serious results will be obviated.
The foregoing is the preferred way of carrying the present invention into effect,
but it will be obvious that having given the general idea, certain alterations may
be made without departing from the spirit of the invention. Thus for example,
instead of inserting the sleeve I in the intervening space between the neck bush H
aud gun metal gland D, the shoulder on the follower may be made a little larger

page_text: in diameter and the sleeve inserted between it and the neck bush H, or a
projecting flange might be provided on the inside of the stuffing box A for one end
of the sleeve to bear against. In the latter case however it is preferable to split
the sleeve into two or more pieces to enable it to be readily inserted.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, as communicated to me by
my foreign correspondent, I declare that what I claim is-
1. In a metallic packing for piston rods, valve rods and the like, in which a
neck bush is used at the end of the stuffing box through which the rod slides, the
arrangement for keeping the said neck bush firmly in its proper position, namely,
inserting between the said neck bush and a solid abutment, a bush or sleeve such
as I or its equivalent, said bush, sleeve or its equivalent being so arranged that
the neck bush shall be locked firmly in place and be prevented from moving by the
motion of the rod, or even by the pressure of the steam in the cylinder, substantially
. as described.
2. The improvement in metallic packings for piston rods, valve rods, or the like
of the kind set forth, namely, inserting between the neck bush H and a solid
abutment formed either by the gland D, or by a flange on the follower F, or by a
flange on the inside of the stuffing box a bush or sleeve I so arranged as to hold
the said neck bush firmly in its proper position, substantially as described.
3. In combination with the metallic packing substantially as herein described
and shown the metallic bush or sleeve I for the purposes set forth.
Dated this 9th day of May 1896.
WM. P. THOMPSON & Co.,
Agents.