US1975656A - Valve mechanism - Google Patents

Description

Oct. 2, 1934. w. F. lRViN 1,975,656

VALVE MECHANISM Filed June 18, 1931 2 Sheets-Sheet l E: i g 0 E 16 o 17 1- 1 7: 18 2 5 22 2 2 I I I 2L 66 Z6\V V 5 9 i1 6 71 61 v lNVENfOR WITNESSES.

Patented Get. 2, 1934 warren er 1::

VALVE MECHANISM Walter IF. Erwin, Pittsburgh, Pa, assigncr, hy mesnc assignments, to Ruth M. Hook, Pitts= burgh, lPa.

, Application June 18, 1931, Serial No. 545,163

3 Claim.

This invention relates to a combined regulatin and shut-01f valve mechanism for both positively turningon and shutting off the flow from one pressure system to another, and for also regulating the pressure in the lower of the two, and while not necessarily so limited is intended for use more particularly for controlling the flow of fuel to gas fired furnaces and combustion devices of that character.

The primary object of the invention generally stated is to provide an improved valve mechanism of the type disclosed in United States Patent No. 1,764,790, granted June 17, 1930 to C. H. Hook and N. L.,Mercur for a Combined pressure regulating and shut-oil valve. A more particular object, however, is to provide such a mechanism with a secondary safety pilot valve which is adapted to be rendered responsive to the fire in the burner with which the mechanism is used and to 2 positively insure the combined valve mechanism operating as a shut-on" valve in case the fire in the burner is extinguished for any reason what soever.

These and other objects, as well as the various I other novel features and advantages of the invention, will be apparent when the following de= tailed description is read in conjunction with the accompanying drawings, of which Fig. 1 is a sec= tional view of a single embodiment of the invention; Fig. 2 a simple schematic wiring diagram of a control system for automatically controlling the operation of the primary pilot valve utilized to determine the operation of the main flow valve; Fig. 3 is a sectional view to an enlarged scale of the pilot valve mechanism shown in Fig. 1; Fig. 4 a front elevational view of the same; and Fig. 5 a sectional view taken on the line VV of Fig. 4.

In accordance with the invention as illustrated in the drawings, a combined pressure regulating and shut-off valve mechanism is provided which comprises a valve casing consisting of three de= tachably connected sections 1, 2 and 3. The lower or these, section 1, forms the valve casing proper and is provided with a pair of threaded openings 4 and 5 for connecting it in the fuel line of a gas firedfurnace or similar pressure system. Across the casing there is extended a partition 6 which divides it into an inlet chamber 7 and an. outlet chamber 8. A valve opening 9 is provided in this partition and in it a valve 11 is arranged to sea to control the flow therethrough.

Between the adjoining ends of sections 1 and 2 of the casing, which are open, there is arranged a flexible diaphragm 12, and to it a valve stem 13, connected to valve 11, is attached. A similar but larger diaphragm 14 is arranged between the upper end of casing section 2 and the lower end of casing section 3, both such sections being of a dish shape to allow for an increase in the area (CH. 158=-117.ll)

of diaphragm 14 over diaphragm 12. Between the two diaphragms a chamber 15 is formed by casing section 2 which is utilized as a pressure chamber for operating valve 11, both diaphragms functioning as pressure responsive elements, diaphragm 12 being responsive to the difierence in. pressure on its two sides and diaphragm 14 to the pressure in chamber 15.

For transmitting the movement of diaphragm 14 to diaphragm 12 and hence to valve 9, a pair of levers 17 are employed. The upper ends 01 these levers are connected by links 18 to a bracket 19 which is secured to diaphragm 14 and their centers pivotally engaged at 21 in a bracket 22, mounted on the bottom of casing section 2, while their lower ends are arranged to engage a head 16 to which the end of stem. 13 is connected. Hence when diaphragm 14: is forced upwardly the lower ends of levers 17 are forced against head L6, urging valve 11 toward its seat. To vary the pressure required in chamber 15 to move diaphragm 14. upward sufficiently to close valve 11, weights 23 of difierent sizes may be mounted on top of diaphragm 14, or any other adjustable means, such as a spring disposed between the diaphragm and the top of the cover casing sec= tion 3, may be used for such purpose. 4

When properly installed for use, chamber 7 is arranged to connect with the high pressure sys tem or fuel supply and chamber 8 with the low pressure system or the burners of a furnace, and to utilize pressure chamber 15 for operating valve 11, ducts 24., 25 and 26 are provided in casing section 1 for transmitting to that chamber the pressures obtaining in chambers 7 and 8. When chamber 7 is connected to chamber 15, the pressures on the two sides of diaphragm 12 are the same and valve 11 falls closed due to gravity. However, if the pressure is sufiicient, as it usually is, to lift diaphragm 14 against the force of weight 23, the levers 17 apply a pressure to head 16 and positively hold valve 11 on its seat. Accordingly, when such a connection is made, valve 11 functions as a positive shut-ofi valve. When the connection between chamber 7 and chamber 15 is shut ofi and chamber 8 is connected with chamoer 15, the pressure in the latter chamber is the same as that in chamber 8. Hence a difference in pressure exists on the two sides of diaphragm 12 with the greater pressure in chamber 7 tending to lift valve 11 from its seat. Opposingthe upward movement of diaphragm 12' are levers 17 which are urged against it by diaphragm is when a sufiicient pressure is established in chamber 15 to lift weight 23, and, because of the greater area of diaphragm 14, it is adapted to maintain a se-= lected pressure in chamber 8, determined by the size of weight 23 when duct 25 is open, causing valve 11 to function as a pressure regulator.

For controlling the connections between chambers '7 and 8 and 15, a pilot valve 2'7 is arranged in a valve chamber 28 in casing section 1, and into it each of these connections extend. The valve is so arranged as to be selectively moved to close or open either of the ducts 24 or 25. In the particular embodiment shown valve 27 is arranged to move in a horizontal plane, and when in its inner position to close the end of duct 24 and when in its outer position to close the end of duct 25. This valve is mounted on a stem 29 which is reciprocably mounted in a bore 31 in a body casing 32, which in turn is demountably secured to casing 1 and designed to form the outer wall of valve chamber 28. To simplify the operation of valve 27, duct 24 is extended through valve body 32 to bore 31 which is enlarged at its inner end to permit the pressure to be communicated to chamber 28 about stem 29.

To adapt pilot valve 2'7 to be operated from remote points, an electromagnet is employed consisting of a solenoid 33 and a movable armature 34. For supporting these a pair of plates 35 are secured to the sides of body 32. Between such plates an L-shaped permeable core 36 is mounted with one leg extended downwardly, and upon it solenoid 33 is attached. The remainder of the magnetic circuit is formed by armature 34 which, like core 36, is L-shaped in form. This armature is pivotally secured at one end by a pin 3'7 between plates 35.

To facilitate the connection of solenoid 33 in a control circuit, its leads 38 and 39 are connected, respectively, to a pair of terminals 41 and 42 mounted on an end plate 43 attached to the ends of plate 35. This end plate is preferably formed of current insulating material and is shaped to fit within a tube 44 fitted over the whole pilot valve structure to form a housing therefor.

For moving armature 34 away from core 36 and yieldably connecting it to valve stem 29, a small leaf spring 45 is employed. One end of this spring is engaged in a lug 46 at the top of plates 35. and it is connected midway between its two ends at 4'7 to the top of armature 34, the connection being so made as to flex the spring in a direction to constantly urge the armature away from core 36. From 47 the spring is extended along the back of the armature, and its lower end, which is slotted at 48 for such purpose, is fitted over an annular groove 49 cut on the end of valve stem 29. With this arrangement, when solenoid 32 is deenergized, armature 34 is urged to its open position by spring 45 and carries valve 27 to its seat at the end of duct 25. When energized the armature is moved to its closed position, seating valve 2'7 over the end of bore 31 which also constitutes the end of duct 24, the spring 45 permitting relative movement of valve 2'7 with armature 34 and insuring seating of the valve in both directions of operation.

In order that pilot valve 2'7 may be operated manually in the absence of a control circuit being established for solenoid 33, or in case there is a failure in such circuit, a bolt 51 is provided in valve body 32, the bolt being arranged for movement in a vertically disposed bore 52 out in body 32 at one side of the bore 31 in which valve stem 29 moves. Cooperating with bolt 51 is a pin 53 which is arranged to move in a horizontal bore 54. This pin is adapted to engage bolt 51 at one end and the back of armature 34 at the other. As shown, the upper end of bolt 51 is tapered at 55 on the side engaging pin 53. Consequently as it is pushed upward it forces the pin and armature outward, the amount of movement so produced being sufficient to carry valve 2'7 to its seat in the end of duct 24, but insufficient to engage the end of the armature with core 36, a small gap 56 being allowed between these members when operated in this manner for a purpose which will presently appear.

While the taper 55 on bolt 51 is suflicient to close valve 27 on its seat at the end of duct 24, when the bolt is moved its full distance upward pin 53 engages the flat side of the bolt, and because of the pressure exerted on the pin by spring 45, it applies such a force to the bolt that the latter is retained in its upper position until it is pulled down by force, or solenoid 33 is energized. The energizing of the solenoid pulls armature 34 tightly against core 36, closing gap 56 whereby the force on pin 53 is released to such an extent that bolt 51 falls to its inactive position due to gravity. To prevent the bolt falling from bore 52 when so released, a set screw or any other suitable means may be arranged to engage it. By reason of this automatic release feature, if the pilot valve is operated manually .while the control circuit connected to solenoid 33 is deenergized for any cause whatever and the circuit thereafter set in operation, the pilot valve is automatically placed under the control of the solenoid and the control circuit as soon as the solenoid is energized and armature 34 moved to close the gap 56 between it and the core 36. The

advantage of this will be readily appreciated by those skilled in the art.

In heating systems utilizing valves of this nature it is highly essential that provision be made for insuring against the escape of gas in case the fires are extinguished due to abnormal causes such as may be brought about by explosions occurring in the combustion chamber, or more frequently by a temporary failure in the gas supply, or by numerous other causes. To provide against the existence and continuance of such a condition, which may easily result in disastrous consequences, it is a feature of this invention to provide a secondary or safety pilot valve 61 which is adapted to positively insure valve 11 operating to shut off the fiow of fuel in case the furnace fires are extinguished, and to do so independently of the position of valve 27 when such condition occurs.

As shown in the drawing, this latter pilot valve is arranged in a valve chamber 62 formed in casing section 1 and through it duct 25 connecting chamber 8, which pressure chamber 15 is extended. The valve is mounted in a sleeve 63 which has a valve seat on its lower end and an opening in its side registering with the portion of duct 25 extending above chamber 62. Hence when valve 61 is closed, duct 25 is shut ofi, and when open, the duct is open. With such arrangement, when valve 61 is closed valve 11 can not be operated as a regulator no matter where valve 27 is located when it is closed. To insure valve 11 being closed if duct 24 is shut off by valve 2'7 when valve'61 is closed, a small bleeder opening 64 is extended from chamber '7 into valve chamber 28. This bleeder connection is so proportioned that it does not interfere with the normal operation of diaphragm 14, as controlled by valve 2'7, but does afiord a suficient connection between chambers '7 and 15 to close valve 11 at all times when valve 61 is closed.

For operating valve 61 it is connected by a stem 65 with the outer end of a flexible tube 66 which has its inner end attached to a shoulder 67 on the outer end of sleeve 63. About tube lllll) by use of bolt 51.

66 there is provided a'casing 68 which forms with it a pressure chamber 69. This chamber is in turn connected by a length of tubing 71 to a bulb or other suitable container '72. This container together with tube '71 and chamber 69 are filled with a. thermally expansible fluid which is adapted to collapse tube 66 and force valve 61 away from its seat when heated, and the bulb 72 in pilot light, such as pilot 73, connected to the same gas supply." Hence as long as a fire is maintained by pilot 73, valve 61 is held open, but in case it goes out, the fluid in bulb 72 contracts and valve 61 closes. This closes duct 25, and as bleeder 64 insures a pressure in chamber 15 equal to that in chamber 7, valve 11 is closed. When valve -11 is closed in'this fashion it can not be reopened until pilot 73 is relighted and valve 61 opened. As will be readily appreciated, such a feature affords both a safe and positive protection against gas leaks whether valve 27 is operated either manually or automatically.

In normal operation the casing section 1 is connected in the fuel supply line to a burner or furnacebeing controlled by valve 11 and a selected weight 23 is placed on diaphragm 14 to give the desired regulation of fuel pressure to the burner. In addition, solenoid 33 is connected in a con trol circuit such as that shown in Fig. 2, in which, as indicated, there is usually included a source of current supply, represented by transformer 75, a hand switch 76, a room temperature responsive thermostatic switch '70 provided with contacts 7'7 and '78, a burner operated thermal switch 79, and a boiler pressure switch 81. These switches and parts making up this circuit are all well known and. need no further description here inasmuch as they in themselves form no' part of the present invention. In such a circuit, when switch 76 is closed and transformer is energized, solenoid 33 is placed under the control of switches 79 and 81 and thermostat 70, which is the usual room type thermostat. Thethermostat is usually adapted to close the circuit and maintain it closed below a preselectedtemperature and open it above such temperature. When closed, solenoid 33 is energized and duct 24' closed by valve 27, rendering valve 11 operable as a regulator for determining the pressure at which the fuel is supplied to the burners. When open, the solenoidis dee'nergized and valve 27 moves to openduct 24, closing duct 25 due to the resultant action of armature 34. This causes valve 11 to be closed. In addition, if either switches '79 or 81 open notwithstanding the position of the thermostat contacts 77 and 78, the solenoid circuit is interrupted and causes valve 11 to close. This latter is a customary safety feature in systems of this type. As set forth above, in case of a failure or absence of current supply in the control circuit, valve 27 may be operated manually Such latter form of control, however, is automatically released, as also set forth above, if solenoid 33 is energized.

Among the outstanding advantages of the invention is that afforded by the secondary pilot valve 61 which under all conditions of operation,

notwithstanding the position of any of the other valves, closes and causes valve 11 to be positively closed if the fire in the furnace or pilot lights '73 goes out. Hence it positively insures against gas leakage due to fire failure. It will-be readily understood by those skilled in the art that valve 61 may be operated by other means and in response to other condltionsthan that illustrated but such are intended to fall within the scope of the appended claims.

I. claim as my invention:

1. A combined pressure regulating and shut-off valve mechanism for controlling the flow of fluid from one pressure system to another comprising in combination, a main valve adapted to be connected between two such systems, a pressure responsive element for operating said valve, means for connecting said pressure responsive element to the pressure line at both the high and low pressure sides of said main valve, a primary pilot valve for selectively controlling the connection between said pressure responsive element and said line connections, an auxiliary pilot valve arranged to render said primary pilot valve inactive when it is operated to connect'said pressure responsive element to the low pressure side of said main valve, and a bleeder connection extending from the high pressure side of said main valve to said pressure responsive element, such bleeder connectionbeing insufiiciently large to interfere with the operationof the pressure responsive element when the latter is connected to the low pressure side of the main valve to act as a regulator.

2. A combined regulating and shut-off 'valve mechanism comprising in combination a valve casing having in itan inlet chamber, an outlet chamber and a pressure chamber, a valve. disposed in a valve opening connecting said inlet chamber with said outlet chamber, a pressure responsive element arranged in said pressure chamber and operably coupled to said valve, 2. pressure connection between said inlet and outlet chambers and said pressure chamber, a primary pilot valve for normally controlling said connection, a secondary pilot valve for closing said outlet chamber connection with said pressure chamber, and a bleeder connection between said inlet chamber and said pressure chamber connection for establishing a pressure in said pressure chamber corresponding to the pressure in said inlet chamber when said secondary pilot valve is closed independently-of the position of said primary pilot valve.

3. A flow controlling mechanism for use with a gas fired burner comprising a valve casing adapted to be connected in a fuel line, said-casing having in it an inlet chamber, an outlet chamber and a pressure chamber, a valve disposed in a valve opening connecting said inlet with said outlet chamber, a pressure responsive element arranged in said pressure chamber and operably coupled to said valve for controlling its operation, pressure connections between said inlet and outlet chambers and said pressure chamber,'electro- 1 responsive means adapted to be operable by remote control for selectively opening and closing the connection between said inlet chamber and said pressure chamber, thermally responsive means for shutting off said outlet chamber and pressure chamber connection independently of

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