вход по аккаунту


Патент USA US3090602

код для вставки
May 21, 1963
Filed May 18, 1959
United States Patent 0 "ice
Patented May 21, 1953
side, is a resilient valve disc 30 which cooperates with
annular valve seat 20 to control the ?ow of ‘gas through
port 18. The diaphragm 28 is also provided with a disc
32 of predetermined weight which acts to bias the valve
Thomas P. Fleer, A?ton, Mm, assignor, by mesne assign
ments, to White-Rodgers Company, a corporation of
Filed May 18, 1959, Ser. No. 813,363
5 Claims. ((11. 251—-30)
This invention relates generally to diaphragm-type gas
30 in a closed position on seat 20 when the pressures act
ing on opposite sides of diaphragm 28 approach equality.
Communication between inlet chamber 12 and cham
ber 26 is provided by connecting passages 34, 36, 38,
the lower portion of a blind vertical bore 40, and a pas
sage 42. The passage 38 enters the bottom of the blind
bore 40 concentrically and forms a lower seat 39 on which
valves in which biasing means is effective to hold the
valve closed when gas line pressure is ‘applied to both
sides of the diaphragm and in Which the valve is opened
against the biasing means by dropping the pressure on one
side of the diaphragm to atmospheric. More particularly,
a ball-type pilot valve 44 movable vertically in the bore
4%} is arranged to seat under certain conditions, thereby
to out 01f the communication between chambers 12 and
the invention relates to the incorporation of means to
e?ect a stepped-opening movement in valves of this type 15 26 just described. A disc member 46 positioned inter
mediately of the bore 4% is provided with a central aper
wherein the valve in caused to move from its closed posi—
ture 48 which forms an upper seat arranged to he engaged
tion in an opening direction a predetermined initial
by the pilot valve 44 under other conditions. The pilot
‘amount at a relatively rapid rate and thereafter to con
valve is provided with a stem 51} which extends upwardly
tinue to move openward to its full open position at a
‘relatively slow rate. The purpose of this manner of valve 20 and exteriorly of the bare 41} through a ?exible diaphragm
52. The diaphragm 52 is attached at its periphery to the
operation is to provide an immediate limited flow of fuel
cover member 22 by a suitable clamping ring 54 and the
to a gas burner, thereby to provide for the establishment
stem 50 is suitably attached to the central portion of the
of‘ initial limited combustion in a burner combustion
diaphragm in ?uid pressure sealing relationship, whereby
chamber and to delay a full flow of fuel to the burner
long enough to permit the development of su?icient
natural draft through the combustion chamber to support
the ?exible diaphragm permits vertical movement of the
valve stem 519 while providing a ?uid pressure tight closure
of the open end of bore 40. A compression spring 56
biases the pilot valve 44 on its upper seat 48.
Under conditions wherein the pilot valve 44 is in its
downward position communication between the chamber
its combustion.
An object of the invention is the provision of simple,
reliable, and novel means for e?ecting a “stepped-open
ing” operation of a diaphragm gas valve wherein the valve
26 and atmosphere is provided through the passage 42,
is caused to move openward from its closed position a
the lower portion of bore 40, the aperture 48 in disc 46,
predetermined initial amount at a relatively rapid rate
the upper portion of bore 40, an ori?ce 58, a passage 60,
and then continue to move openward to its fully open
a passage 62, and a bleed tube 64 to atmosphere. A
‘position at a relatively slow rate.
35 threadedly adjustable valve 66 having a tapered point 68
A further object is to provide “stepped-opening” means
adapted to variably enter the ori?ce 58 provides a variable
in a diaphragm valve ‘whereby the extent of the initial
restriction in the communication just described between
rapid moving portion of the valve opening movement may
chamber 26 and atmosphere.
be varied and whereby the speed of the relatively slow
Communication between chamber 26 and the outlet pas
moving portion of the valve opening movement may be
sage 14 in the valve body is also provided under condi
tions wherein pilot valve 44 is on its lower seat. This
More speci?cally, it is an object to provide a diaphragm
communication is traced from chamber 26 through pas
gas valve in which line pressure existing in the fuel con
sage 42, through the lower portion of bore 40, through
duit on the upstream side of the valve and atmospheric
pressure existing on the downstream side of the valve
when it is closed are applied to opposite sides of the dia
phragm to effect a rapid partial opening movement of the
valve, and in which restricted communication between the
low pressure side of the diaphragm and atmospheric pres
sure exterior of the fuel conduit is provided to eiiect con
tinued opening movement of the valve to its full open
position at a relatively slow rate after the pressure dif
aperture 48, through the upper portion of bore 40, through
a passage 70, a passage 72, a variable ori?ce 74 in a disc
76, a passage 78, a bore 8%, and a passage 82 to outlet
passage 14. A check valve 84 movable axially in the bore
80 and biased in a closed position by a compression spring
86 cuts oif the just described communication between
chamber 26 and outlet passage 14 when the pressure dif~
ferential between these points decreases to a preselected
point. The compression spring 86 bears at one end against
check valve 84 and at its other end against a threadedly
adjustable member 88 by means of which the closing force
value due to the partial opening of the valve.
by spring 86 to the check valve 84 may be varied.
Further objects and advantages will appear from the
A threadedly adjustable valve 91} having a tapered end 92
following description and accompanying drawing.
arranged to be variably entered into ori?ce 74 provides a
The single FIGURE of the drawing is a longitudinal
restriction in the communication line between
cross-sectional View of a diaphragm gas valve constructed
60 chamber 26 and outlet passage 14.
in accordance with the present invention.
The pilot valve 44 is arranged to be moved from its
Referring to the drawing, numeral 10 indicates a valve
biased position on upper seat 48 to its lower position on
body having an inlet chamber‘12, an outlet passage 14,
seat 39 by an electromagnetic actuator 94. The actuator
and a partition 16 which separates the inlet chamber from
94 includes a pivoted armature 96, the free end of which
the outlet passage. The partition is provided with a port
overlays the exteriorly projecting upper end of pilot .valve
18 formed with an annular valve seat 20. The valve
50. When the electromagnet is energized the arma
body 10 is provided with a cover 22 attached thereto by
turre 96 is attracted downward thereby moving pilot valve
screws 24. The cover 22 has a chamber 26 formed
44 to its lower seat 39.
therein lying opposite the inlet chamber 12 in the valve
body, and a ?exible diaphragm 2S clamped at its periphery
*In the drawing the electromagnetic actuator 94 is shown
between the valve body 10 and cover 22 forms a ?exible 70
in a de-energized position and pilot valve 44 is biased on‘
movable wall dividing chambers 12 and 26. Attached
its upper seat 48. Under these conditions when the dia
to the central portion of diaphragm 23, and on its lower
ferential in the fuel conduit between the upstream and
downstream sides of the valve drops to an inoperative
phragm valve device is connected in a fuel supply line 11
between a source of fuel supply under pressure and a
duce the restriction at ori?ce 74 in order to achieve the
necessary discharge from chamber 26 to effect the desired
rapid-opening movement of valve 30 before the pressure
dilferential is lost.
The extent to which the valve 30 opens rapidly may be
selectively varied in any particular installation and for any
burner 13 havinga" fuel metering ori?ce 15, supply line
pressure will exist in chambers 12 and 26 and equal pres
sure will therefore be applied to both sides of the dia
phragm/28 under static conditions. The valve 30' will
consequently be closed under these conditions due to the
supply line pressure by varying the spring pressure ap
,weight of disc 32. Also, under closed valve conditions,
plied to seating check valve 84. As the spring pressure
the pressure in outlet passage 14 will be atmospheric be
is increased the amount of rapid valve opening movement
cause of its communication with atmosphere through the 10 will be decreased. ‘This occurs because as the spring
length of supply line 11 leading to the burner and through
pressure is increased the rapid venting of chamber 26 to
the usual fuel metering ori?ce 15 at the inlet of the burner.
outlet passage 14 is cut off earlier. It will be noted that
When it is desired to open the valve 30, the electromag
_ in this arrangement, with all other in?uencing factors
netic actuator 94 is energized by suitable circuit means,
thereby effecting the movement of pilot valve 44 from its
upper seat 48 to its lower seat 39. This action cuts off
‘the communication between chamber 26 and inlet cham
ber 12 and establishes communication between chamber
26 and the outlet passage 14 and between chamber 26 and
the bleed tube 64 through the now open passage 48. The
chamber 26 is now vented to atmosphere through a ?rst
communication branch which includes the variable restric
tion 74 and the check valve 84 and through a second
communication branch which includes the variable restric
tion 58.
Line pressure in chamber 12 now acts on the
constant, the extent of the initial rapid valve opening ste
will vary directly with the cross-sectional area of th
burner metering ori?ce and inversely with line pressure.
The device is therefore self-compensating, with respect to
these two factors, to limit the momentary head pressure
at the burner ori?ce to that which will supply an initial
amount of fuel for initial limited combustion which is
proportionate to the size of the burner ori?ce irrespective
of supply line pressure.
The foregoing descriptionis intended to be illustrative
and not limiting, the scope of the invention being set
forth in the appended claims.
under side of diaphragm 28 to displace it upward and to
I claim:
lift the valve 30 from its seat. It is to be understood that
1. In a diaphragm gas valve, a main valve body having
the biasing force holding check valve 84 on its seat is
a ?rst chamber formed therein, a main fuel inlet passage
in all instances less than that required to hold it closed
way leading to said ?rst chamber, a main fuel outlet pas
against a line pressure-atmosphere differential when 30 sageway leading from said ?rst chamber, and a main valve
stepped-opening operation of the valve is desired.
controlling said outlet passageway, a cover member for
As valve 30 begins to lift from its seat the pressure in
said valve body, a second chamber ‘formed in said cover
the outlet passage 14 increases above atmospheric. This I
member, a ?exible diaphragm forming a dividing Wall be
is due in part to resistance to flow through the length of
tween said ?rst and second chambers and being operative
supply line extending from the device to the burner, but in
ly connected to said main valve, means biasing said valve
considerably greater part usually to the restrictive effect
in a closed position, means forming a ?rst communicating
of the fuel metering ori?ce 15 at the burner. Continued
passageway connecting said ?rst and second chambers,
opening of valve 30 results in a further increase in the
and means forming a second communicating passageway
pressure in outlet passage 14, and when this pressure
leading from said second chamber to atmosphere, a two
reaches a predetermined point, the check valve 84 will
position pilot valve operative to alternately close and
close thereby cutting 01f communication between chamber
open each of said communicating passageways as it is
26 and outlet passage 14. Chamber 26 will, however, con
moved back and forth from its one position to the other,
tinue to vent to atmosphere through the second branch of
means forming a branch of said second communicating
the venting passages and bleed tube 64'and the valve 30'
passageway leading from a point in said second communi
will continue to move open to its full open position, but 45 cating passageway between said pilot valve and atmospher'
.at a considerably slower rate as predetermined by adjust
to a point in said main fuel outlet passageway downstreani
ment of the valve“ with relation to ori?ce 58.
from said main valve, and a normally closed check valve
When the pilot valve 44 is moved to its lower seat 38 .
in said branch communicating passageway arranged to
thereby subjecting the diaphragm momentarily to the
open when the pressure in said branch communicating pas
maximum pressure differential, the response of the dia 50 sageway is greater than that in said main fuel outlet pas
phragm 28 is rapid and it will tend to overshoot the desired
amount of initial rapid opening movement if venting of
2. A diaphragm valve as in claim 1 having a variable re—
chamber 26 is not suitably restricted. The diaphragm and
striction in said branch communicating passageway.
attached valve 30 will after overshooting settle back to
3. A diaphragm valve as in claim 1 having a variable
some point as the pressure builds up in outlet passage 14,
restriction in said second communicating passageway be
but this ?uctuation is undesirable and varies in degree as
tween the take-oif of said branch communicating passage
between installations. Usually other factors being equal,
way and atmosphere.
the overshoot will be greater in installations where the run
4. A diaphragm valve as in claim 1 having a variable
of fuel supply conduit between valve 30 and the fuel
restriction in said second communicating passageway be
metering ori?ce at the burner is longer and less when the
tween the take-olf of said branch communicating passage
run of fuel conduit is shorter. This is so because in the
way and atmosphere and in said branch communicating
instance of a long run of fuel supply conduit there is a
greater space at atmospheric pressure between valve 30
5. A diaphragm valve as in claim 1 including means
and the burner metering ori?ce under closed valve condi
for applying a variable biasing force to hold said check
tions into which a greater amount of ?ow may discharge
valve in a closed position.
through outlet passage 14 before the velocity drops and
References Cited in the ?le of this patent
back pressure builds up due to the restrictive metering
It is desirable therefore to increase the restriction at
ori?ce. 74 under conditions resulting in a relatively slow
pressure build-up in outlet passage 14, in order to slow
'down the venting of chamber 26 to outlet passage 14 to
reduce this overshoot. On the other hand, it will be nec
essary under conditions which result in a very rapid pres
sure build-up in passage 14 upon opening valve 30 to re 75
Hodgdon _____ -1 _______ __ Apr. 4, 1916
Gauger ______________ __ July 16, 1940
Beam _____~_________ __ Mar. 16, 1943v
2,638,920 '
Berkholder ____________ __ Aug. 7,
Taylor ______________ __ Feb. 15,
Schaefer ____________ __ Apr. 29,
Woodhull ____________ __ May 19,
Без категории
Размер файла
438 Кб
Пожаловаться на содержимое документа