US1617437A - Boiler-water-level control - Google Patents

Description

5 1 F 927 c. F. DE CORSE.

BOILER WATER LEVEL CONTROL Filed Dec. 23, 1924 Char/es fie Cars e,

INVENT OR A TTORNE Y Patented Feb. 15, 1927.

,.'UNITED STATES CHARLES F. DE CORSE, 01? L05 ANG'ELES, CALIFORNIA.

BOILER-WATER-LEVEL CONTROL.

Application filed December 23, 1924. Serial No. 757,700.

The present invention relates to water 1 level control for steam boilers and has for its principal object to provide an etficientwater level control of extreme simplicity.

Another object of the invention is to provide a water level control in which all levers, toggle arms, packed swivel joints and the like .are dispensed with.

Another object of the invention is to provide a water level control which is devoid of floats and in which all parts are exposed to view and subject to inspection.

. Another object of the invention is to provide a boiler water level control which will tend to keep the boiler feedpump operating constantly but at well controlled speed, so that the'water level will remain practically constant and unchanged, even under conditions where the steam consumption is spasmodic.

Floats, levers, inaccessible valves, packed, sliding and swivel joints, compound levers, and like parts common to boiler water level controls, are generally recognized as troublesome and dangerous, and it is an object of the present invention to eliminate such parts and to produce a simple, efiicient, leverless, direct acting device, in which the weight of water column in communication with the boiler acts directlyup on a sensitive or balanced pressure valve to control flow of steam to a boiler fed pump.

Further objects and advantages of my invention-will appear hereinafter and will be better understood by virtue of the order of their occurrence.

' I have illustrated by the accompanying drawings a preferred embodiment of my invention. The embodiment is shown by way of example only, and numerous other embodiments will suggest themselves to the minds of those skilled in the art, and I do not limit myself to any specific construction or arrangementof parts, and may alter the construction and arrangement of parts, Without enlarging the scope of my invention,

within the appended claims.

In the said drawings,

-Figure 1, is a plan. view of an embodiment of my invention as it appears when applied to a horizontal fire tube steam boiler.

Figure 2, is a side elevation thereof.

'Figure 3, is an enlarged detail section seen mainly on a line 33 of Fig. 1,

The embodiment illustrated is shown as applied to a common type of horizontal boiler 6, and it is assumed, for example, that the water level is to be maintained at the line 77. In applying my invention to th1s or any other type of boiler, I provide an external tank or receiver 8, of comparatively small capacity. The tank is connected to the boiler by a water pipe 9, which enters the boiler, as at 10, below the normal water level line. A steam line, or pressure equalization line 11, connects the upper parts of the receiver with the boiler, as at 12,

above the water level line. Thus the steam pressure and water level within the receiver will always be the same as it is in the boiler, and the receiver, together with the water line and the equalization line, provide a water column,

A balanced pressure valve of the s 001 type, such as valve 14, is provided. aid valve is connected between inlet and outlet pipes, respectively, and will control the fluid flowing in the direction indicated by the arrows. As will be apparent hereinafter, the valve will be caused to assume positions corresponding to the rate at which water is evaporated by the boiler. If the source of water will provide a pressure in excess of the boiler pressure, then the spool valve may be employed to control the flow of water to the boiler. If the water is at a low head and a boiler feed pump (not shown) is employed, then the valve is em ployed to control the flow of steam to the boiler. The manner in which the boiler water level control valves are connected to water or steam mains, or to pulsometers, pumps and injectors, is well understood and need not be considered herein.

The receiver is provided with two upright hanger rods 15, terminating at the upper end in washers 16. A bracket 17 is employed to support the tank; coil springs being interposed between the washers and the bracket so that the tank is resiliently suspended. The water line connects to the receiver through a T fitting 18, and a push The push rod is divided intermediate of its length so that each corresponding end at the point of division terminates in a C shaped member 20. Adjacent each C shaped member there is provided a spring seat member 21, of disc like proportions that is fixed to the corresponding part of the push red, as at 22. A combined'tension and compression spring 23 is secured at respective ends, as at 24; and 25, to respective discs, and so arranged that the C shaped members are normally spaced as shown. Should the valve stick, or should its effective Weight, or the pull required to lift it, be increased, then the respective parts of the push rod will move apart or together until a contact'member 26 on one C member will abut a similar contact on the other C member. The operator or observer of my improved water level control can detect the slightest interference to which the valve is subject, by observing the relative position of the two C members. The contact members are preferably insulated from the metal rods, as by a block of insulating material 27,and from each contact an insulated wire may lead. Byplacing the contacts and wires in an alarm circuit, a gong or other signal (not shown) may be caused to operate whenever the valve is subjected to any resistance not normally known to exist;

In installing and adjusting the device, the spring 23 is left neutral; neither expanded or compressed. The characteristic of the springshould be such that slight movement on part of the rod in either direction will effect a corresponding movement on the part of the other section of rod. The springs which support thetank are adjusted so that when water exists in the tank up to the desired level the valve will be in closed position. It is to be understood that a balanced pressure valve requires a practically negligible force to open or close it.

In the operation of the device the water level in the tank and in the boiler will be the same. The pipes which connect the tank and the boiler may be of any suitable material or size, and I have found that regular wrought-iron pipe will serve the purpose in the most economical and practical manner. Owingto the length of the pipe it is com- 'paratively flexible, particularly when it is realized that a movement of only one eighth inch is all that is required for moderate sizes of balanced pressure valves. In fact if the tank were unsupported the pipes would allow the tank to descend several inches.

When the boiler is in operation the tank will finally assume aposition where it will hold the valve always slightly open and will throttle the fluid passing through the valve to such extent that the boiler is constantly supplied with Water. In fact the entire de vice may be so adjusted that the change in water level will be hardly noticed. The push rod, with the interposed spring, may be considered an elastic rod and forms a suitable connection between the tank and valve under normal condition. The elasticity of the rod is limited by the C members, and should the contacts come into abutment, then the rod is no longer elastic. It will be apparent, generally speaking, reduced water level will lighten the'floating tank and open the valve, while increased water level will add to the weight of the tank and force the valve closed.

hould the valve leak or become in'lproperly seated a leak through the valve would con tinue to supply the boiler with water. As a consequence the water level would rise above that desired, but the weight ofthe tank would increase. Subsequently the upper section of the divided rod would be forced down until the electric contacts are brought together and the gong is sounded.

To'explain another advantage of my device it will be assumed that the water level drops and the tank is lightened. If the valve is not opened thereby and the water supply is continually depleted, then the tank will rise until the contact elements connect and give the danger signal. Or, let it be assumed that the valve opens, but for some reason water is not delivered to the boiler. This might be due to the fact that the steam supply is cut off at its source, or the pump becomes stalled, or a leak develops between the pump and the boiler. In any such event the danger signal would eventually be sounded.

Now it will be apparent that I have provided a water level control for steam boilers free from floats, levers, packed joints, stuffing boxes and the like. In addition, the device is arranged to sound an alarm in case the valve is faulty in operation, and withal it will be seen that I have provided a device of extreme simplicity, and which will detect its own faults in operation.

I claim:

1. In a boiler water level control, the combination with a resiliently mounted tank connected externally with the boiler in a manner to rise and fall with corresponding change of water level in the boiler, of a valve controlling the supply of water to said boiler, a stem to said valve, and a spring interposed between the stem and tank; said spring being the sole operative connection between the stem and tank whereby movement of said tank without corresponding accompanying movement of said valve stem will be manifest by the change of length of said spring.

2. In combination with a boiler water level control device having a member which is caused to change position by change in water level, a valve for controlling supply of water to said boiler, a stem to said valve, and a spring connecting said valve stem and said member; said spring being the sole operative connection between the stem and member whereby appreciable movement of said member, without accompanying movement on the part of said valve stem results in change of length of said spring, a contact fixed relative to said member, and another contact'fixed relative to said stem; said contacts normally spaced apart but arranged to contact with each other when appreciable change in length of the springs occurs.

3. In a boiler water level control, the combination with a resiliently mounted tank connected externally with the boiler in a manner to rise and fall with corresponding change of water level in the boiler, a valve controlling supply of water to said boiler, a stem in said valve, and a spring interposed between the stem and tank; said spring being the sole operative connection between the stem and tank whereby movement of said tank without corresponding accompanying movement of said valve stem will be manifest by the change of length of said spring, a contact fixed relative to said tank,

,another contact fixed relative to said stem;

said contacts normally spaced apart but arranged to contact with each other when the spring is changed in length to a predetermined extent.

CHARLES F. DE CORSE.

Images