US2279976A - Automatic safety device for boilers - Google Patents

Description

April '14, 1942; w, c, FAUST 2,279,97

I AUTOMATIC SAFETY DEVICE FOR BOILERS F iled May 16, 1938 3 Sheets-Sheet 1 -1Wmn April 14, 1942. w. :.v FAUST y AUTOMATIC SAFETY DEVICE FOR BOILERS Filed May 16, 1938 3 Sheets-Sheet 2 April 14, 1942.

w. c. FAUST 1 AUTOMATIC SAFETY bEVICE FOR BbILERS Filed May 16, 1938 3 Sheets-Sheet 3 Patented Apr. 14, 1942 v f UNITED STATES PATENT OFFICE AUTOMATIC SAFETY DEVICE FOR corneas William 0. Faust, corpus Christi, "Tex.

Application May 16, 1938, Serial No. 208,163

3 Claims. (01. 122-448) This invention relates to an automatic safety device for boilers.

The invention embodies certain improvements over the inventions disclosed in my co-pending applications, Serial No; 168,962, filed October 14, 1937, and Serial No. 178,484, filed December '7, 1937, on Safety devices for boilers.

Anobject of the invention is to provide improved means adapted for use in connection with boilers for maintaining a safe water level in the boiler; for controlling the supply of fuel to the boiler water feed pump, or the supply of water from said pump to the boiler may be controlled so as to insure an additional supply of water to the boiler in case the water level in the boiler becomes too low for safety.

With the above and other objects in view the invention has particular relation to certain npvel features ofconstruction, operation and arrangement of parts, examples of which are given in this specification and illustrated in the accompanying drawings, wherein:'

Figure 1 shows a side elevation of the complete device shown partly in section and installed on a boiler.

Figure 2 shows a longitudinal, sectional view of the automatic fuel control valve mechanism.

Figure 3 shows a longitudinal, sectional View of the automatic valve cut ofi mechanism.

Figure 4 shows an enlarged, vertical, sectional View of an automatic control valve mechanism employed.

Figure 5 shows a side elevation, partly in section, of the valve mechanism shown inFigure 4. Figure 6 shows a side elevation of another embodiment of the invention, partly in section, and i i a Figure 7 shows an enlarged sectional view ofa type of valve employed for controlling the steam lines to the boiler feed pump. and to the fuel cut off valve mechanism.

Referring now more particularly to the drawings wherein like numerals of reference designate the same parts in each of the figures, the numeral l designates the boiler whose furnace is equipped with any conventional type of burner 2 to which is equipped with an automatic fuel control valve mechanism 4 and an automatic valve out off mechanism 5 both of which will be morespecifically hereinafter described.

water level in the float chamber.

Mounted on a suitable support there is a tank 1 whose lower end is connected into the water chamber of the boiler in the bottom thereof by the line 8. The water level in the boiler and in the tank I will be maintained the same. The tank contains a float chamber in which there is a suitable float 9 which rises and falls with the The lower end of this float is pivotally connected to one end of the lever Ill. The other end of this lever is extended into the lateral extension ll of the tank and is pivotedon the transverse pin 12 across said extension. The lever ID will move vertically in accordance with corresponding movements of the float 9. Between the pivotal connections of the lever I'll it also has a pivotal connection with the upstanding valve stem I 3 hereinafter referred to.

The numeral M designates generally the boiler feed pump which is of conventional construction. The pump takes the water from a suitable source through an inlet line l5 and delivers it into the boiler through the feed line It as shown in Figure 1 or Ilia as shown in Figure 6.

Leading outwardly from the steam dome ll of the boiler there is a steam pipe l8 which leads to the automatic fuel. control valve mechanism 4 and which has a branch line I9 which leads directly to the engine of the pump M as shown in Figure 1, or the branch line Illa, as shown in Figure 6 which leads to said engine and which maybe controlled automatically as hereinafter,

explained. The lines [9, I911 are each equipped with a manuallyoperable shut off valve I911.

The pressure in the boiler and in the tank 1 is equalized through an equalizing line 20 which is connected to the top of the boiler and also into the top of said tank and said equalizing lineis extended and connected into the automatic fuel cut off valve mechanism 5. The boiler is also equipped with a conventional relief valve mechanism 2| which serves as a safety valve to relieve excessive pressures in the boiler.

The extensionof the line 2i]. is indicated by the numeral 20a and this extension is equipped with a safety valve mechanism 22, of conventional construction, which is arranged to open under sure in the boiler, irrespective of the water level in the boiler.

Mounted on the extension ll of the tank 1 there is an automatic control valve mechanism having the valve casing 23. This casing may be bolted to the extension II as shown in Figure 5. Its lower end is closed by the guide plug 24 through which the lower end of the valve stem l3 works and said plug contains a stufling box 25 surrounding said stem. Bolted on to the casin 23 there is a bonnet 26 containing a cylinder 21 whose upper end is closed by the plug 26a. The stem is extended upwardly into the cylinder and its upper end is reduced and fixed on said upper end is a slide valve 28 which fits closely in the cylinder. A stufling box 29 surrounds the valve stem and is clamped between the bonnet and the casing 23. As illustrated in Figure 1 the valve casing 23 is incorporated into the feed line l6 which forms a conduit for the passage of water i from the pump to the boiler, and spanning the conduit and located within the valve casing 23 there is a partition 33 having upper and lower valve seats 3|, 32 with the downwardly opening valves 33, 34, controlling said seats and arranged to open and close said conduit. Connected into the pipe 28 and into the upper end of the cylinder 21 there is a pipe and leading out from the side of said cylinder and connected into the extension pipe 200. there is a connecting pipe 33 whose inner end is normally closed by the slide valve 28. In case of failure of the water supply or should the water become too low the float 9 will descend causing the valves 33, 34 to open to admit additional water to the boiler. If, for any reason, the pump should fail to operate or an insufficient supply of water be furnished the float will continue to descend until the valve 28 uncovers the inner end of the pipe 36 whereupon steam will be admitted into the branch pipe 23a and into the automatic cut off valve mechanism 5 and the fire in the boiler furnace will be extinguished.

As illustrated in Figure 6, the water feed line Isa leads from the boiler feed pump directly into the boiler and the branch line [9a, through which steam is supplied to operate said pump, is controlled by the control valve mechanism shown in Figure 4. In the embodiment shown in Figure 6 in case the water in the boiler becomes too low the valves 33,. 34 will be opened as hereinabove explained and steam will thus be automatically supplied to operate the pump to deliver additional water to the boiler through the feed line lfia and if, for any reason, the water supply should fail, the float will continue to descend, uncovering the inner end of the pipe 36 and admitting steam to the valve mechanism 5 to close the same and cut off the supply of fuel to the burner.

Referring now to Figure 2 wherein there is shown in detail the automatic fuel control valve mechanism which has a cylindrical valve casing 31 formed of two longitudinal sections fitted together and whose ends are reduced to receive the couplings 38, 38 whereby the sections are maintained in assembled relation and the joints may be suitably packed with gaskets as 39, to prevent leakage. Mounted in the casing 31, there is a cylinder 40, in which there is mounted the reciprocable piston 4|. This piston is equipped with a sectional piston rod 42 whose sections have a threaded connection, as shown, for adjustment. The forward end of the cylinder is formed with a head 43 having a central bearing to receive the piston rod 42 and on this end of the piston rod there is a valve 44 arranged to cooperate with the tapering inside seat 45 of the casing 31. Between the head 43 and a stop 46 on the piston rod, there is a strong coil spring 41 which surrounds the piston rod 42 and the compression on which may be regulated by an appropriate adjustment of the sectional piston rod. The other end of the cylinder 40 is closed by the plug 48 and the steam line 18 extends through the casing 31 and may be welded thereto and is connected into the cylinder 40 behind the piston 41 through the plug 48 as shown in Figure 2.

Variations in the steam pressure will react against the piston 4| to control the position of the valve 44 and the feed of fuel to the burner. Under ordinary running conditions, the valve 44 will be only partly closed in accordance with steam pressure. In case of high pressure, the resistance of the spring 41 will be overcome so as to move the valve 44 toward closed position so as to reduce the supply of fuel. After the pressure is lowered, the spring 41 will move the valve 44 further open to admit an increase of the supply of fuel to the burner. Should the pressure become dangerously excessive and should the automatic cut-ofi valve mechanism 5, hereinafter more specifically described, fail to function, the valve 44 will be completely closed to completely out off the supply of fuel to the burner and extinguish the flame. This automatic fuel control valve mechanism accordingly acts as a governor.

The automatic cut-off valve mechanism 5 is illustrated in Figure 3. It is substantially similar in structure to the automatic control valve mechanism, excepting that the spring 49 is weaker than the spring 41 and the piston rod 58 is not adjustable to regulate the compression on the spring 49 and the steam line 28a is connected into the cylinder 5| through the plug 52. The construction of the casing 53 is the same as that of the casing 31 and is formed with the valve seat 54 similar to the seat 45 with which valve 55,

corresponding to the valve 44, cooperates. The coil spring 49 surrounds the piston rod 58 and is interposed between the cylinder head and the piston 51 which is mounted to reciprocate in the cylinder 5|. In case of excessive steam pressure sufficient to open the valve mechanism 22, said pressure will pass through the steam lines 28, 28a, to instantly close the valve 55 and to out off the supply of fuel to the burner 2 to extinguish the flame.

Under normal running conditions with the water in the boiler at normal or substantially normal level, the float 9 will be in its elevated position, the valves 33, 34 will be closed and the slide valve 28 will close the inner end of the pipe 36. As the water level is lowered the float 9 will descend and in the form shown in Figure 1, water will be delivered to the boiler through the delivery pipe I6 and if sufficient water is not thus delivered, upon further descent of the float,

the slide valve 28 will open the pipe 36 and admit steam to the automatic cut off valve mechanism 5 to cut oif the supply of fuel, and as previously stated, in case of excessive steam pressure, irrespective of the water level steam will be supplied pump to pump additional water to the boiler and should the water supply fail and the float continue to descend, steam will be admitted through the pipe 35, 36, 20a, to close the automatic cut off valve mechanism 5, and extinguish the fire in the furnace. V l l The drawings and description disclose what is now considered to be preferred forms of the invention by way of illustration only,while the broad principle of the invention will be defined by the appended claims.

.What I claim is:

1. The combination with a boiler having a fuel burner and a supply line for fuel leading to the burner, of a cut-off valve mechanism in the fuel line, a steam conduit leading from the steam chamber of the boiler and connected to said valve mechanism, a safety valve controlling the flow of steam through the conduit and arranged to be opened by the steam pressure to admit steam to the valve mechanism whereby said valve mechanism will be operated to close said fuel, supply line, a by-pass steam conduit for by-passing the steam around the safety valve, a control valve assembly for controlling the by-pass conduit, said control valve assembly comprising a casing, a bonnet positioned on the casing and forming a cylinder having an inlet and an outlet connecting the cylinder with the by-pass conduit, a pistonvalve fittedclosely in'the cylinder and controlling the flow of steam from the inlet to the outlet to control the supply of steam, through the by-pass conduit, to the cut-off valve mechanism, the casing of the control valve assembly having an inlet and outlet for the flow of water therethrough to the boiler, a valve stem reciprocab-le in the bonnet and easing, a water control valve on the stem controlling the casing outlet,

seals around the stem on opposite sides of the water control valve, said piston valve being connected to the stem whereby the flow of steam through said cylinder from the inlet thereof to the outlet thereof is prevented until the water control valve has been opened and means in cluding a float operable in accordance with variations in the level of the liquid inthe boiler to open the water control valve and the piston valve in succession upon downward movement of the 2. The combination with a boiler having a fuel burner and a fuel supply line leading to the valve mechanism, a safety valve controlling the .1

valve in said casing will initially open the valve flow of steam through the conduit and arranged to be opened by steampressure to admit steam to the valve mechanism to actuate the same to close said fuel supply line, .a by-pass steamvconduit, 3

the steam chamber of the boiler and with said I cut-off valve mechanism; a control valve assembly for controlling the supply of steam through theby-pass conduit to the cut-off valve mechanism, said control valve assembly comprising a casing, a bonnet positioned on the casing and forming a cylinder which has an inlet and an outlet connecting the cylinder with the by-pass conduit, a piston valve fitted closely in the cylinder and controlling the flow of steam from said inlet to said outlet, the casing of the control valve assembly being incorporated into a water feed line leading into the boiler, a valve stem reciprocable through the casing and extended into the bonnet and to which the piston valve isv attached, a balanced valve on the stem in the casingfor controlling the flow of water through I said feed line, seals around the stem on opposite sides of the balanced valve, means including a float movable in accordance with variations in the level of the liquid in the boiler to control said balanced valve and whereby upon descent of the float the balanced valve will be initially opened to admit water to the boiler and upon further downward movement of the float the piston valve tended into the extension and pivoted thereto,

a valve mechanism comprising a casing mounted on said extension, a bonnet positioned on top of the casing and forming a cylinder,- a by-pass steam conduit, said cylinder having a, steam inlet and a steam outlet connected into said conduit, a .piston valve fitted closely in the cylinder, a stem pivotally connected at one end to said lever and extended through the casing and to the-other end of which the piston valve is attached, a water feed line into which, the casing is incorporated, a valve seat within the casing through which the water flowing through the feed line passes, a valve on the stem for opening and closing the seat, sealing means between the stem and the casing on opposite sides of said last mentioned valve, said valves normally closing said outlet and seat respectively and the piston valve being arranged relative to said outlet so that the seat, upon downward movement ofthe float and therefore the piston valve will move into position to open said outlet upon further downward movemen of the float.

. WILLIAM C. FAUST-

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