Improvements in Valves for the Air Cylinders of Blowing Engines, Air Compressing Engines, and the like.
Year: 1899

page_text: Date of Application, 27th Mar., 1899
Complete Specification Left, 27th Dec., 1899-Accepted, 27th Jan., 1900
PROVISIONAL SPECIFICATION.
Improvements in Valves for the Air Cylinders of Blowing Engines,
Air Compressing Engines, and the like.
I, TOM WESTGARTH, of the Firm of Sir Christopher Furness, Westgarth and
Company, Limited, Middlesbrough-on-Tees, in the County of York, Engineer,
do hereby declare the nature of this invention to be as follows:-
This invention relates to valves to be used for admitting and exhausting air
to and from the cylinders of blowing engines, air compressing engines and the
like.
The form of valve to which my invention is applicable consists of a circular
disc the face of which is flat and the back extended in the form of an annular
piston which will work in a cylinder formed on the valve guard by extending
therefrom a central boss fitting the valve spindle and an outer wall forming an
annular space which the said annular piston closes and fits. The defect of this
arrangement is that when the piston is driven into the cylinder there is nothing
to cushion the motion thereof, and the tendency is for the valve to hammer the
guard.
The object and result of my invention is to reduce this tendency by means of
air admitted into the cylinder and locked therein by the piston towards the end
of its stroke the compression so caused acting as a cushion against the valve.
In describing my invention I will refer to its application to the inlet and outlet
valves of the usual blowing engine of a blast furnace, and in carrying the same
into effect I preferably mount the inlet and outlet valves one above the other on
a spindle and which are placed between the air cylinder of the blowing engine
and the blast furnace pipe and furnished with the usual valve seats and guards.
The working part of the valve, which takes the form of a flat circular disc, is
furnished with an annular piston which works in a corresponding cylinder
formed in the guard of the valve. An air passage formed in the central bolt or
spindle communicates with the cylinder the air port being so placed that it is
closed by the valve piston towards the end of its upward stroke and in such a way
that air is compressed in the cylinder at each stroke of the valve, thus reducing
the tendency of the valve to hammer when working, that is to say that the position
at which this air passage opens into the cylinder is such that after the valve has
lifted part of its stroke the piston works over the air port and automatically closes
the air passage so that the remainder of the air in the cylinder is compressed.
This air passage is controlled by a governing valve adjustable externally so that
the pressure of air in the cylinder can be varied at will.
The valves may be made of any substance, preferably metallic, and are some-
times faced with ebonite, wood fibre, canvas, leather, or other material.
Instead of the piston forming part of the valve and working in a corresponding
cylinder formed in the guard of the valve as already described, the piston to con-
trol the valve may be fitted in a separate cylinder and connected by a spindle to
the valve the air being compressed in this separate cylinder by the inward stroke
of the piston as the valve lifts in the manner already described.

page_text: In some cases I arrange a separate valve communicating with the air passage
in the valve spindle to allow for the air to pass in and out of the air compressing
cylinder, this valve to work automatically and to be connected to the cylinder
in a suitable way.
Dated this 25th day of March 1800
Improvements in Valves for the Air Cylinders of Blowing Engines,
Air Compressing Engines, and the like.
I, TOM WESTGARTH, of the Firm of Sir Christopher Furness, Westgarth and
Company, Limited, Middlesbrough-on-Tees, in the County of York, 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 valves of the kind to be used for admitting and ex-
hausting air to and from the cylinders of blowing engines, air compressing engines
and the like.
A convenient form of valve to which my invention is applicable consists of a
circular disc the face of which is flat and the back extended in the form of an
annular piston which will work in a cylinder formed on the valve guard by
extending therefrom a central boss bored to fit the valve spindle and an outer
wall forming an annular space which the said annular piston closes and fits. The
defect of this arrangement is that when the piston is driven into the cylinder
there is nothing to cushion the motion thereof, and the tendency is for the valve
to hammer the guard.
The object and result of my invention is to reduce this tendency to a minimum
by means of air admitted into the cylinder and locked therein by the piston to-
wards the end of its stroke, the compression so caused acting as a cushion against
the valve. There are other incidental advantages.
In describing my invention I will refer to its application to the inlet and outlet
valves of the usual blowing engine of a blast furnace, from which its application
to other similar purposes will be readily seen.
And in order that my invention may be clearly understood and readily carried
into effect, I will proceed to describe the same with reference to the accompanying
drawings, in which Fig. 1 is a sectional elevation of a set of inlet and outlet valves
fitted to a blowing engine and constructed according to my invention. Fig. 2 is
a similar view to Fig. 1, but shewing a modification of an outlet valve in which
the piston to control the valve is fitted in a separate cylinder and connected by a
spindle to the valve; and Fig. 3 illustrates in detail a separate air valve to work
automatically.
In the drawings, a represents the inlet valve and 6 the outlet valve mounted
one above the other on a spindle c and which are placed between the air cylinder d
of the blowing engine and the blast furnace pipe e and furnished with the usual
valve seats a 6' and guards a 6. The working part of the valve which takes
the form of a flat circular disc is furnished with an annular piston f which works
in a corresponding cylinder g formed in the guard of the valve. An air passage h
formed in the central bolt or spindle e communicates with the cylinder g, the air
port being so placed that it is closed by the valve piston f towards the end of its
』

page_text: opens
upward or inward stroke and in such a way that air is compressed in the cylinder
at each stroke of the valve, thus reducing the tendency of the valve to hammer
when working, that is to say that the position at which this air passage
into the cylinder is such that after the valve has lifted part of its stroke the piston
works over the air port and automatically closes the air passage so that the re-
mainder of the stroke of the piston is met by the resistance of the air which is
confined and compressed between the valve and the valve guard. This air pass-
age his controlled by a governing valve such as the set screw i adjustable ex-
ternally so that the pressure of air in the cylinder can be varied at will by
throttling or opening the said passage.
The valves may be made of any substance, preferably metallic, and are some-
times faced with ebonite, wood fibre, canvas, leather, or other material.
As shown in Fig. 2, instead of the piston forming part of the valve and work-
ing in a corresponding cylinder forming part of the valve guard as already de-
scribed with reference to Fig. 1, the piston f to control the valve 6 may be fitted
in a separate cylinder ; and connected by a spindle k to the valve, the air being
compressed in the separate cylinder by the inward stroke of the piston as the
valve lifts in the manner already described with reference to Fig. 1. The air
passages h¹h are controlled by snifting valves which allow the air to escape after
being compressed in the cylinder j.
In some cases I arrange a separate valve 7 of ordinary description communi-
cating with the air passage h in the valve spindle to allow for the air to pass in
and out of the air compressing cylinder g, this valve to work automatically and
to be connected to the cylinder in any suitable way as shown in Fig. 3.
It will be seen from the foregoing description that my improvements are not
to be confined to the particular arrangement of parts shown nor to the use thereof
in connection with the blowing engines of blast furnaces only as the invention is
applicable to air blowing or air compressing engines which may be designed or
adapted for other purposes, providing a piston valve momentum requires to be
cushioned towards the end of each upward or inward stroke to prevent hammering
the valve guard and the expression "blowing engine" as used in the claims is in-
tended to include such other blowing or air compressing engines.
Having now particularly described and ascertained the nature of my said in-
vention and in what manner the same is to be performed, I declare that what I
claim is:-
As a means to prevent hammering in blowing engines between the valve and
valve guard for the air cylinders.
(1.) The arrangement in combination therewith whereby air is compressed
between the valve and the valve guard in a manner adapted to cushion the valve,
substantially as hereinbefore described with reference to Fig. 1, of the ac-
companying drawings.
(2.) The arrangement in which a piston connected by a spindle to the valve is
fitted into a separate cylinder whereby air is compressed within the said cylinder
by the traverse of the piston and in a manner adapted to cushion the valve, sub-
stantially as hereinbefore described with reference to Fig. 2. of the accompanying
drawings.