US2318801A - Electrical control system for valves - Google Patents

Description

May 11, W. A. RAY ELECTRICAL CONTROL SYSTEM FOR'VALVES Filed April 22, 1940 INVENTOK W/W/Mz Z ATTOKNEY Patented May 11, 1943 ICE 2,318,801 v amc'rmcar. comm. SYSTEM FOR VALVES William A. Ray, Glendale, cam. Application April 22, 1940, Serial No. 330,872

Claims.

This invention relates to a system for operating electromagnetically controlled valves; and more particularly to a system of this character that includes an electrically driven timing device.

In one application of this invention, a valve, utilized to control the flow of fluid fuel, such as gas, is arranged to be automatically closed in the event that the pilot burner be extinguished. For

this purpose, the valve is arranged to be operated to open position by the aid of current generated by a pilot generator, usually in the form of a thermo-pile. The current thus generated may be used in any appropriate manner to control the 'valve, as by direct operation of the valve closure by a solenoid or by fluid pressure control. The

system may also be placed under the control of a time switch or a thermostat or both.

Under any circumstance, the available power of a pilot generator is very low. Therefore the electromagnet for controlling the valve operation must be so designed that its armature or core may be pulled to its attracted position by the available power, for causing the valve to open; and when the pilot generator ceases to function due to the extinguishing of the pilot flame, the armature or core is released to cause the valve to close.

It is one of the objects of this invention to make it possible to supply power from the pilot generator to another power consuming device, in addition to the valve controlling magnet, and in spite of the fact that the pilot which does not materially exceed that which is required to control the valve. This additional power consuming device may be the electric timer or clock mechanism used in the same system; the important requirement of such an additional device is that it consume power only intermittently. This is true of many forms of clock mechanisms.

This result is accomplished by taking into consideration the fact that the power needed to hold an armature or core in attracted position is very much less than to pull a magnetic member such as an armature or core to that position. Therefore once the magnetic member is attracted, a large portion of the available power may be consumed by the timer without danger of the member dropping out. And in the event that the pilot generator becomes inactive, the stopping of the clock indicates this inactivity in a simple manner. Lighting of the pilot flame 'will cause attraction of the member between the periods of the intermittent load provided by the timer.

It is accordingly anotherobiect of this invengenerator has an output tion to provide a combination electrically driven clock and electrically controlled safety valve operated from a common source of weak power,

such as a pilot generator.

This invention possesses many other advantages, and has other objects which may be made more easily apparent from a consideration of one embodiment of the invention. For this purpose there is shown a form in the drawing accompanying and forming part of the present speciflcation. tail, illustrating the general principles of the invention; but it is to be understood that thisdetailed description is not to be taken in a limiting sense, since the scope of this invention is best defined by the appended claims.

Referring to the drawing, the single figure is a diagrammatic illustration of a system incorporating the invention.

In the present instance, the system is illustrated as utilized for control of gaseous fuel. Main burner l is adapted to be supplied with fuel through a conduit 2. Interposed in this conduit 2 is a valve 3, such as asafety valve. This valve 3 is shown in this instance as having closure 4 which is intended to be urged to the closed position shown, whenever a pilot flame 5 is extinguished. A valve of this character is shown in a prior application filed in the name of William A. Ray, on August 2, 1938, under Serial No. 222,673, and entitled Pilot-operated valve.

The pilot flame fuel through a pilot burner 6 connected by a conduit l to the inlet side of the valve 3.

The valve 3, as described tion hereinbefore, identified, is provided with an electromagnet having a movable magnetic member adapted to be attracted by the electromagnet. This electromagnet and its armature or core may be enclosed in the housing 8 attached to the top of the valve structure 3. The coil 30 of the electromagnet, and its armature 3i are merely diagrammatically ing posts 9 for the coil 30 are supported oiithe top of the housing 8.

In order to causethe it is necessary for the its core or armature 3|.

valve structure 3 to open, electromagnet to attract This is accomplished by power derived from a thermopile l0, having hot junctions afiected by the heat of the pilot flame 5.

This thermopile or pilot generator l0 quickly ceases to function upon extinguishing of the flame 5. Under such circumstances the electromagnet controlling the valve 3 is deenergized and the valve 3 is closed.

This form will now be described in de- 5 is shown as provided with in the prior applicaindicated in the drawing. Bind- The power capable of being supplied by the pilot generator I is very limited. Accordingly it has not been proposed heretofore to make it possible for the pilot generator to supply any load other than the operation of a valve controlling electromagnet coll, such as 30. Nevertheless, it is quite advantageous to make it possible to operate other devices by power derived from the thermopile I0. For example, an electrically driven clock or timer mechanism II is advantageously utilized in connection with the valve control. The clock mechanism II may operate a circuit controller or switch I2 placed in series with the electromagnet. In this way the valve 3 is not maintained open except for such periods as the circuit controlled I2 is closed, as determined by the clock II. valve which may be located to the right of the valve structure 3 in conduit 2 would be ineffective to supply fuel to the burner I until this switch I2 is closed; and in spite of the fact that the flame 5 is heating the hot junctions of the thermopile ID. If desired, a, supplemental thermostat control mechanism I3 may also be provided in series with the circuit controller I2. This thermostat control may be so arranged as to ensure closing oi the valve 3 unless the temperature reaches a definite low value. All this'ls well understood. and further description thereof is considered unnecessary. I

By providing a clock mechanism II which requires power only at intermittent periods, the thermopile I0 may be employed effectively to supply power for the entire system. The electromagnet coil 3|] for controlling the operation of the valve 3 requires substantially all of the power supplied by the thermopile II), to cause it to move its magnetic member 3| from unattracted to attracted position. This it can accomplish during those periods between requirements of power to drive clock II. When the clock II is intermittently energized, there is still sufficient current flowing through the electromagnet to hold the magnetic member 3| in attracted position. However, in the event that the pilot flame 5 is extinguished, the electromagnet coil 30 is entirely deenergized, and the valve 3 closes.

The clock mechanism which draws power intermittently from the thermopile I0, may take any one of several forms. In the present instance it is diagrammatically illustrated as including a magnetic armature I4 mounted on an oscillating shaft I5. This armature I4 is urged in a clockwise direction by a hair spring I6. The outer end I! of the hair spring I6 is attached to a stationary post. Its inner end is connected'to the oscillating structure. The armature I4 is adapted to be influenced from the position illustrated, by magnetism flowing through the pole pieces I8 and I9. These pole pieces I8 and I9 when coils and 2| are energized, exert a torque upon the armature I4 in a counterclockwise direction. The arrangement is such that shortly after this rotation begins, the coils 20 and 2| are disconnected. The inertia of the armature I4 is sumcient to carry it over a considerable angle in a counterclockwise direction, even after the coils 20 and 2| are deenergized. Under the influence of the hair spring I6, this rotation is in time stopped, and the hair spring then turns the armature I4 back to the position illustrated. As soon as this position is reached, the circuit through the driving coils 20 and 2| is reestablished and the cycle is repeated.

The manner in which this circuit is reestab- Thus a manual electromagnet to hold its magnetic member 3| in lished will now be described. The armature I4 carries contact pin 22. This contact pin is in electrical connection with the armature l4 and the inner end of the hair spring I6. It cooperates with a spring contact arm 23 mounted on a stationary portion of the apparatus. When the pin 22 is in contact with arm 23, the coils 2B and 2| are placed across the leads 24 and 25 which are connected to the thermopile II. Thus the complete circuit through the coils 20 and 2| may be traced as follows: from lead 25, coil 20, finger 23, pin 22, armature I4, hair spring I6, post II, coil 2|, back to lead 24.

An intermittent drive 26 is shown as driven by shaft I5 upon which the armature I4 is mounted. This drive may be connected as by aid of a shaft 21 to the hands 28 of the mechanism.

The energization of coils 20 and 2| thus depends uponthe making of contact between the post 22 and the finger 23. This contact is made only for relatively short periods separated by periods when there is no energy consumption by mechanism II. During these periods, between the intermittent energization of coils 20 and 2|, the thermopile I0 is capable of causing full energization of electromagnet coil 30 to cause valve 3 to open. Thereafter the valve 3 is maintained open, due to the lower power requirements of the attracted position.

What is claimed is:

1. In combination, a source of electricity of limited power, an electromagnet having a magnetic member adapted to be attracted and held by the electromagnet, and connected to said source,

and an intermittent load connected in parallel with the electromagnet, said source being capable of energizing the electromagnet sufiiciently to cause the electromagnet to attract the member only in those periods when the load does not require power, and capable of energizing the electromagnet sufficiently when the load is energized, for causing the electromagnet to hold the member in attracted position.

2. In a system of the'character described, a source of electricity, a valve, an electromagnet for controlling the valve, a circuit connecting said electromagnet with said source, an intermittent load, and a circuit comiecting said load with said source, said electromagnet having a magnetic member adapted to be attracted to and held in attracted position by the electromagnet, said source having a power output less than that required for simultaneously energizing the intermittent load and the electromagnet for attracting the magnetic member, said output being sufficient for causing the electromagnet to attract the magnetic member between energizations of the intermittent load, as well as suflicient to energize simultaneously the intermittent load and the electromagnet to hold said member in the attracted position.

3. In a system of the character described, a source of electricity, a valve, an electromagnet for controlling the valve, a circuit connecting said electromagnet with said source, a timer mechanism having a magnetizing coil as well as means for intermittently connecting said coil with said source, said electromagnet having a magnetic member adapted to be attracted to and held in attracted position by the electromagnet, said source having a power output less than that required for simultaneously energizing the intermittent timer mechanism and the electromagnet for attracting the magnetic member, said output 1 agsiaeci being sumcient for causing the electromagnet to attract the magnetic member between energiza.

1 "and the electromagnet to hold said member in tions oi. the intermittent timer, as well as sum; A cient to energize simultaneously the intermittent timer and the electromagnet to hold said member in attracted position, and a circuit controlleritor' the electromagnet and operated by the timer mechanism.

Q. In a system of the character described, a

thermopile adapted to be operated by the heat of a pilotflame, a valve controlling flow of fuel to be ignited by the flame, an electromagnet for controlling the valve, a circuit connecting said electromagnet with the thermopile, and a timer mechanism having a magnetizing coil as well as means for intermittently connecting said coil with the thermopile, said electromagnet having a magnetic member adapted to be attracted to and held in attracted position by the electromagnet, said thermopile having a power output less than that required for simultaneously energizing the intermittent timer and the electromagnet for attracting the magnetic member, said output being suflicient for causing theelectromagnet to attract the magnetic member between energizetions of the intermittent timer, as well as suilicient the attracted position. a

5. In a system of the character described, a thermopile adapted'to be operated by the heat of a pilot flame, a valve controlling flow of fuel to be ignited by the flame, an electromagnet for controlling the valve, a circuit-connecting said electromagnet with the thermopile, a timer mechanism having a magnetizing coil as well as means for intermittently connecting said coil with the thermopile, said electromagnet having a magnetic adapted to be attracted to and held in attracted position by theelectromagnet, said thermop'ile havinga power output less than that required for simultaneously energizing the intermittent timer and the electromagnet for attracting the magnetic member, said output being suflicient for causing the electromagnet to attract the magnetic member between energiza'tions of the intermittent timer, as well .as sufficient to energize simultaneously the intermittent timer and the electromagnet to hold said member in the attracted position, and a circuit controller for the electromagnet and operated by the timer mechanism. WIILIAM A,- RAY.

Images