Improvements in Packing for Valve Rods or Spindles and the like.
Year: 1894

page_text: Date of Application, 30th Mar., 1894-Accepted, 2nd June, 1894
COMPLETE SPECIFICATION:
Improvements in Packing for Valve Rods or Spindles and the like.
I, EMIL HEINRICH CONRAD OEHLMANN, of 131 Linien Strasse, Berlin,
Germany, 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 a packing for movable rods or spindles and it has for
its object to prevent the rods jamming in their up and down movements.
This is a very common defect with the existing packings of stuffing boxes.
In order that my said invention may be properly understood I have hereunto
appended an explanatory sheet of drawings, whereon,
Figs. 1 and 2 are vertical sections and Fig. 3 a cross section.
Fig. 4 is a section of a modification.
In Figs. 1 to 3 the packing consists of a tube a of rubber or other elastic
material, the lower end of which is secured to the rod 6 whilst the upper end is held
tightly in place in the stationary box C.
In order that the rod, when rising shall retain its mobility and that the tube a
shall not be jammed or wedged in by it, a spring d is inserted between the rod and
tube. The coils of the spring are compressed when the valve rod is moving
upwards (the open position of the valve) see Fig. 1 and are expanded when the
rod is falling, see Fig. 2 (closed position of valve) or vice versa.
The spring d effectually prevents friction between the tube a and the rod b, as it
has a greater diameter than said rod. As a consequence it is only necessary to
overcome the spring which presses against the rod at a few points.
The spring can be inserted loose between the rod b and the tube, or one of its
extremities can be fixed to the rod and the other to the stuffing box, so that, in the
latter case the motion of the spring follows that of the rod b. The rubber tube a is
prevented from adhering to the rod by the spring, and, consequently the motion of
the rod is not impaired.
Instead of a spring an insulating layer consisting of an intermediate layer of
single rings of textile fabric, or, as is shown in Fig. 4 of pulverized materials, only
if the materials are of such a nature that they do not stick to the rod.
When using single rings superposed one above the other or cylinders disposed in
the same manner, it is always advisable to make them of a larger diameter than the
rod so as to reduce friction to a minimum.
The characteristic feature of the invention is the insulating of the tube that
constitutes the packing from the rod, said tube having one of its extremities
attached to the rod and the other to the valve box, no matter if a spring, single
rings, a layer of textile fabric or of pulverized materials, constitute the insulating
layer.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
consider novel and desire to claim is :-
A packing for movable valve rods or spindles consisting of a box, through which
the rod or spindle passes, a yielding tube secured at one end to the rod and at the

page_text: other end to the box, and the insulating spring or material inserted between the
tube and the rod to keep the parts from jamming, substantially as hereinbefore
described with reference to the drawings annexed.
Dated this 29th day of March 1894.
H. D. FITZPATRICK,
70, Wellington Street, Glasgow, Agent.