IMPROVEMENTS IN THROTTLE VALVES
Year: 1884

page_text: I, HENRY JOHN PEARSON of Beeston in the County of Nottingham Engineer
do hereby declare the nature of my Invention for "IMPROVEMENTS IN THROTTLE
VALVES" and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement:-
This Invention has for its object improvements in throttle valves.
My improved throttle valve is of that class in which the valve disc together
with its spindle and frame are capable of ready removal from the shell when set
fast whatever the position the valve disc may happen to occupy.
In this throttle valve as in like valves which for some time past have been
manufactured and sold by me the valve disc is carried by a cap which can be
released simply by the removal of bolts which fix the cap to the shell; the cap
with the valve disc can then be lifted away from the aperture in the shell.
As heretofore constructed this cap has had fitted and fixed to it on. its inner side
a separate ring of brass receiving the valve disc.
Now according to my present Invention I form the cap and the frame to receive
the valve disc all in one piece casting them together in iron and boring the casting
afterwards to fit the disc.
The shell is recessed to receive the semicircular under portion of the frame and a
steam tight joint is formed by means of suitable packing or cement.
The joint around the outer edge of the cap and between it and the shell is
formed by means of a ring of vulcanized india rubber.
In order that my said Invention may be most fully understood and readily
carried into effect I will proceed to describe the Drawings hereunto annexed.
DESCRIPTION OF THE DRAWINGS.
Figure 1 is an elevation of a throttle valve constructed according to my
Invention; the cap with the valve disc is lifted from its place.
Figure 2 is a longitudinal section of the same throttle valve with the cap in'
place.

page_text: the cap or cover for this aperture and the ring frame in which the valve disc
works; the same being cast all of a piece. c is the valve disc. The casting b is
bored out to fit the valve disc. d is the spindle on which the valve disc o is fixed,
it has a cross bar or handle at its upper end by which the spindle is turned to set
the valve disc to the desired position. The lower end of the spindle is received
into a small recess b¹in the casting b. The upper part of the spindle d passes
through a stuffing box 62 on the casting b and there is a collar d' on the spindle d
within the stuffing box. e is an ordinary packing of fibrous material over the
collar d', the packing is compressed in the stuffing box by the screw cover f. On
the underside of the collar d' are pins d* entering corresponding recesses, they
serve to limit the rotation of the spindle. 7 is a packing, it may be of fibro and
red lead or other cement forming a tight joint in the recess a¹ of the casing a.
The packing is lodged in a groove in the casting b. h is a ring of vulcanized
india rubber making a tight joint between the part of the casting b forming the
cap or cover proper and the edges of the opening in the casing a.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed I declare that what
I claim is:-
Constructing throttle valves of the class in which the valve disc can however
placed be removed by a side aperture in the casing with the cap or cover of the
said aperture and the frame which receives the valve disc cast all together in one