Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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This inven-tion relates to a variable oriEice
valve.
A well-known and widely used type of poppet valve
employed to control the flow of steam to a soot blower has
an internal supplemental pressure regulating valve disc
for limiting the effective flow past the poppet valve. The
pressure regulating valve disc is threaded on the guide for
the poppet valve and is adjustable, to vary the outlet
pressure/ by removing a plug in the valve body in order to
gain access to the disc. The disc is peripherally notched
50 that when the plug is removed it can be turned by pushing
or prying it with a small bar or screwdriver, to vary the
maximum pressure setting. The space within the valve body
is limited, and time is required to remove the access plug,
so that a substantial period of time is required to gain
access to the disc and to adjust it. The present invention ~;
has as its ob~ect t~e provision of an improved pressure
regulating valve disc construction and improved opera~ing
means therefor which provides not only for more convenient
adjustment of the pressure setting but also permits quick
operation thereof to a fully closed position whereby the ;~
pressure regulating disc can be effectively employed as a
safety shutoff.
A related object is to provide such an improved valve
comprised primarily of standardized proven components ~hich
remain unchanged and wherein only minimum modifications are
required which are simple and of low cost but which do not
impair the reliability or the performance of the valve. ;-
The present invention resides in a valve including
a body having a chamber therein and having an inlet port
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and an outlet port, both of the ports communicating with
the chamber. Valving means is movable -to control ~low
through the chamber between the inlet and outlet, and means
independent o-E the valving means and ac-tual from outside
the body is provided for adjustably limiting the maximum
rate o~ such flow. A seat portion surrounds one of the
ports and faces the interior of the chamber, and an externally
threaded screw portion is provided within the chamber and
fixed to the body and projects towards the seat. The screw
portion is coaxial with the seat. A valve member is in-
dependent of the previously mentioned valving means and is
threadably mounted on the screw portion for movement toward
and from the seat. According to the invention there is
provided an axially elongated gear fast on the periphery
of the valve member with a worm being journaled in the bodiy
and meshing with the gear. Means extends through and is
accessible from outside the body Eor actuating the worm.
The gear is movable axially along the screw portion trans-
versely of the worm when rotated by the worm so that the
valve member is movable toward and from the seat.
~ dvantages wilI become apparent upon consideration
of the present disclosure.
BRIEF DESCRIPTION OF T~IE FIGURES
OF DRAWING
Fig. 1 is a view principally in central vertical
section but partly in side elevation of a valve incorporating
the-principles of the present inven-tion;
; Fig. 2 is a sectional view taken substantially
on the line II-II of Fig. 1 and looking in the direction of
the arrows; and
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Fig. 3 is a fragmentary sectional view showing a modi-
fied construction.
DETAILED DESCRIPTION OF PREFERRED
FORMS OF THE INVENTION
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Reference character 10 designates generally a valve
construction having a body 11 formed to provide a mounting flange
12 surrounding a cylindrical valve inlet chamber 14. Above the
inlet chamber 14 the valve body is provided with an outlet cham-
ber 18 separated from the inlet chamber 14 by an annular radially
inwardly projecting shoulder 20 in which is mounted a valve seat
member 22.
The valve seat member 22 comprises an annular Venturi-
shaped main portion 24 having a hard face 26 at the bottom formed
of a suitable material such as *"Stellite", and having an inte-
gral re].atively thin and flexible outspaced cylindrical support-
ing portion 28 extending outwardly and downwardly from a mid
portion of the body 24 and at its lower extremity secured as by
welding, as indicated at 34, to the wall of chamber 14. The
cylindrical supporting portion 28 is also spaced radially inward-
ly from the wall of chamber 14 except at its secured lower
extremity. Clearance is also provided between the inner wall 16
- of the shoulder 20 and the periphery of the portion of the seat
member 22 which extends upwardly through and to a position slight-
ly above the top of the shoulder. The main portion 24 of the
seat member also has a flat outwardly projecting shoulder 30
which closely underlies but is unsecured with respect to the
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shoulder 20. The upper extremity of the main portion 24 of the
seat member de~ines a flat valve seat portion 78. The valve is
designed for e~ficient handling o~ steam and/or other hot fluids.
In view of the fact that in such service temperature differences
of substantial value will unavoidably exist around the periphery
of the valve body in the area of the valve seat, it will be
appreciated that some distortion of the valve body is unavoid
able. In event of such distortion of the valve body, the seat
member main portion 24 and seat portions 26, 78 carried thereby
will remain substantially undistorted, by virtue o~ the flexi-
bility of supporting portion 28 and the lateral clearances be-
tween the seat member and body, and the relative movability of
the abutting portions 20 and 30.
The seat-engaging peripheral portion 27 of the poppet
valve head 36 is also relatively flexible. The poppet valve head
36 is mounted as by means of the clamping nut 40 on the lower
extremity of the vertically reciprocatable stem 38 for movement
toward and away from the seat face 26 when actuated by the trigger
~ leve~ 62. The stem 38 extends upwardly through a packing gland
: 20 generally designated 48 to a position above the valve body 11
where it is engageable with and actuatable by an arm 67 o~ the
lever 62~ The valve is biased upwardly to closed position by a
compression spring 54 which is trapped between a bottom retainer
formed by a flange 56 on a hat-shaped cap screw 52 which covers :
the packing gland, and an upper sheet metal spring retainer 58
which is keyed to the upper end of the stem 38. Retainer 58 ~as .
flanges 66 which extend upwardly on either side of arm 67 and
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are attached thereto by means of a cotter pin 68 so that in event
of failure of the spring 54 the valve will be positively pulled
upwardly and closed by the trigger lever 62 when it is rocked
clockwise, as viewed in Fig. 1. A peripherally slotted portion
39 of the stem 38, is interengaged with the retainer 58 and the
aperture in retainer 58 is large enough, and the slotted portion
39 is long enough axially, to permit the retainer 58 and flanges
~6 to rock slightly for free movement of the parts.
The stem 38 is slidably supported in a cylindrical
guide 44 wh.ich is externally threaded and secured in a conform-
ably threaded aperture 49 in the top wall 19 of the body 11.
The guide projects both upwardly from the wall 19 to support the
packing gland and downwardly into the chamber 18 to a position
close to the upper extremity of the seat member 22.
A pressure limiting valve disc generally designated 70
is threadabl~ fitted on the exterior of the guide ~4 so that by
rotation on the threads of the latter the disc is movable to and
from engagement with the upper seat portion 78 of seat member 24.
The periphery of the disc is provided with integral axially elon-
gated ~ear teeth 72 which mesh with a worm 74 carried b~ a shaft
76 journaled in the walls of the body 11. Shaft 76 has a squared
or otherwise nonconcentric projecting terminal portion 77 acces
sible from the exterior and adapted to receive a wrench or crank
which permits rotation of the disc to move it along the threads
on the guide, to and from seat portion 78. The worm wheel teeth
72 on the disc are straight and/or itted loosely enough with
respect to the teeth of the worm to permit the disc to move
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axially without binding on the worm. The shaft portion 76 of the
worm pro~ects through a packing gland generally designated 80,
the compression nut 82 of which is provided with a sufficient
range of movement, in proportion to the amount of packing material
83 contained in the gland, so that the gland can be tightened suf-
ficiently by means of the nut 82, to effectively clamp the shaft
against rotation and thereby positively hold the disc in its
adjusted position.
Inasmuch as the inlet 15 of the valve may be connected
to a source of fluid such as steam at a pressure higher than would
be safe to deliver to the served apparatus, a stop may ~e provi-
ded to prevent full opening of the pressure regulating valve disc
member 70. As shown in Figs. 1 and 2, a stop nut 85 fitted on
the valve guide and tightened against the bottom of the wall 19
limits the upward movement of the valve disc 70 and thereby
limits the pressure deliverable to the outlet 21.
In the modi~ied construction shown in Fig. 3, in which
parts similar to those already described are designated by like
reference numbers primed, the stop 85 is omitted, and upward
movement of the valve disc 70' is limited by a flange portion 88
integral with and which extends radially inwardly at the lower
end of the body of the disc 70' far enough to underhang the bottom
end of the guide 44' and limit the upward movement of the disc.
This Detailed Description of Preferred Forms of the
invention, and the accompanying drawings, have been furnished in
compliance with the statutory requirement to set forth the best
mode contemplated by the inventor of carrying out the inven~ion.
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The prior portions consisting of the "Abstract of the Disclosure"
and the "Background of the Invention" are furnished without
prejudice.
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