US1127536A - Steam-generator. - Google Patents

Description

J. M. STABEL.

STEAM GENERATOR.

APPLICATION FILED MAY 19, 1913.

1,1 27,536. Patented Feb. 9, 1915.

4 SHEETS-SHEET 1.

THE NORRIS PETERS C0, FHOTG-LITHO.. WASHINJTCN .2

J. M. STABEL.

STEAM GENERATOR.

APPLICATION FILED MAY 19, 1913 Patented Feb. 9, 1915.

4 SHEETS-SHEET 2.

wfittmssces W W' y k 1A 1.86260! "45 NORRIS PETERS 60., PHOTO-LITHO. WASHINGTON, D, c,

J. M. STABEL.

STEAM GENERATOR.

APPLICATION FILED MAY19, 1913.

1,127,536. Patented Feb. 9, 1915.

Fflgo5 72 4 SHEETS-SHEET a.

"HE NORRIS PETERS CD, PHOTO-LITHQ. WASHINGTON. D. C

J. M. STABEL.

STEAM GENERATOR.

APPLIGATION FILED MAY 19, 1913.

UMTED dTATFid PATENT @FFTfiE.

JOSEPH M. STABEL, OF ROCHESTER, NEW YORK, ASSIGNOR TO DOMESTIC APPLIANCES COMPANY, OF ROCHESTER, NEW YORK, A CORPORATION OF NEW YORK.

STEAM-GENERATOR.

Application filed May 19, 1913.

To all whom it may concern Be it known that I, Josnrrr M. STABEL, a citizen of the United States, and resident of Rochester, in the county of Monroe and State of New York, have invented certain new and useful Improvements in Steam- Generators, of which the following is a specification.

This invention, while applicable in its broadest aspects to steam-generators of various types, relates particularly to the machine shown and described in Letters Patent of the United States to Louis \V. G. Flynt, No. 1,037,884, dated September 10, 1912.

One object of this invention is to maintain constant the steam pressure in the generator, and accordingly to maintain constant the capacity of the machine for work, regardless of variations in the pressure of the source of water supply.

Another object of the invention is to provide means "for feeding a uniform quantity of water to the generator, and at the same time dispose of such surplus water as is not converted into steam when the apparatus is first put into operation.

Still other objects of the invention will be disclosed as the mechanism is described.

In the drawings :-F igure 1 is a central, vertical section of a vacuunrcleaning apparatus embodying the invention in question; Fig. 1 is a side view of part of the apparatus; Fig. 2 is a section on the line 2-2 of Fig. 1; Fig. 8 is a partial plan view, on a larger scale than Fig. 1, with the cover and diffusing-plate removed: Fig. 4- is a section on the line %4- of Fig. 1; Fig. 5 is a section on the line 55 of Fig. 1; Figs. 6 and 7 are both side views looking in the direction indicated by the arrow and line 66 of Fig. 5, and show certain parts in different positions; Fig. 7' is a section on the line aa of Fig. 7; Fig. 8 is a detail view of a part of the lccking-mechanism; Fig. 9 is a central, vertical section of the valvecontrol mechanism on the line 99 of Fig. 5; and Figs. 10 and 11 are, respectively, central, vertical sections on the lines 1010 and 1111 of Fig. 9.

1n the illustrated embodiment of the in- \ention the generator comprises a flashboiler 1 supported on brackets 2 within a casing 3 that has a lining-wall 1. The lower Specification of Letters Patent.

Patented Feb. 1915.

Serial No. 768,683.

end of the boiler is connected with a waterseparator 5, into which it discharges tangentially (see Fig. 1). A pipe 6 leads from the separator 5 to a steam-nozzle 7, and the latter discharges upwardly through a drafttube 8 which, in conjunction with the steamnozzle, constitutes an air-ejector. The separator 5 is provided with a cock 9 for withdrawing water from it. The draft-tube 8 is surrounded by a pipe 10 through which the air and dust discharged from the drafttube 8 are conducted to the chamber 11. The pipe 10 is provided with a pair of lugs 12, 12 and also with another pair of similar oppositely located lugs 13, 13, all of which are adapted to pass through holes in the bottom of the chamber 11 (not shown in the drawings) when the pipe 10 is rotated to bring said lugs in line with said holes, thus permitting the pipe 10 to be pushed up into the chamber 11. T he upper lugs 12, 12 serve to lock the pipe 10 tightly in place by engaging cam projections 14- on the under side of the chamber 11 (see Fig. 1 and the lower lugs 13, 13 serve to hold the pipe in an elevated position within the chamber 11.

A vacuum service-main 15 (see Fig. 1) discharges air and dirt tangentially into a separating-chamber 16, from which the air and finer solid material are withdrawn by the air-ejector through the outlet 17 and duct 18, a flange 19 causing the air and dirt to circulate till the heavier particles of dust are deposited The diameter of the separator-chamber 16 graduallv increases below the flange 19, as shown in Fig. 1. Dirt discharged tangentially into this chamber, as stated, follows the wall of the chamber as it circulates therein and gradually sinks to the bottom 20 of the chamber, where it is deposited adjacent to the wall of the chamber. Only the lighter particles of dust pass out of the separator-chamber through the outlet 17 with the air. Furthermore, the dirt left within the separator-chamber, being deposited near the wall of the chamber as stated, lies, as it accumulates, out of the current of air that passes through and out of the chamber. Access is had to the separator-chamber by a door 21 that is attached to a yoke 22 by means of a screw 23. the yoke being hinged to the separator at 24, 2%, and a locking-device 25 engaging the yoke to look the door in closed position. The separator-chamber and the walls of the duct 18 are cast in one piece, with the exception of the bottom 20, which is secured thereto by bolts 26.

The Water is taken from a service-pipe 27 (Fig. 9), and enters a starting-valve 28 that is adapted to be operated by a lever 29 moved by a chain 30, the lever forcing down the valve-stem 31, to open the valve, against the spring 32. A filter 33 is located within the starting-valve and removable therefrom upon removing the plug 34. The water passes from the duct 35 of the starting-valve 28 into a duct 36 that extends through a sta tionary stem 37 of a reducing-valve, whence.

it passes through a duct 38 in the movable sleeve 39 of said valve and enters the chamber 40 of said valve. The sleeve 39 rests upon a diaphragm 41, and is connected with a plate 42, on the under side of said diaphragm, by means of a plug 43 that is threaded at its upper end, this plug passing through a plate 42 and the diaphragm 41 and being screwed into the sleeve 39. Normally the sleeve 39 is held, by a spring 44, up against a shoulder 45 on the stem This reducing-valve is open when the generator is idle, and is normally open when the generator is in use, but is adapted to be closed by the shoulder 46 on the sleeve 39. When the water, under the pressure of the service-main, passes into the chamber 40 through the ducts 36 and 38, the diaphragm 41 moves downwardly thereby compressing the spring 44, and the shoulder 46 partially cuts off the supply of water from the duct 36, so that the water within the chamber 40 is maintained at lower pressure than that-of the service-main, as water flows through it to the boiler. The spring is compressed between the movable plate 42 and a bracket 47 that may be adjusted vertically by a screw 48, threaded through a boss 49 on the casing. A rod 50, screwed into the nut 43, extends through the screw 48 and maintains the alinement of the movable parts. The sleeve 39 is connected with the diaphragm, and accordingly is acted upon by the water pressure in one direction and by the force of the heavy spring in the opposite direction, so that it is made to move though clogged with sediment. From the chamber 40 the water flows, through a duct 51, into a chamber 52 (see Figs. 9 and 11), whence it passes to the boiler through the duct 53, valve 54 and pipe 55. The automatic cleaner contained within the chamber 52 is one of the features of the invention. It comprises a movable piston 56, that has a hole 57 of proper size to give the boiler the proper amount of water for the normal operation of the machine, a stem 58 of smaller diameter than the hole 57, that is adapted to enter said hole, and a spring 59 that normally holds said piston 56 away from said stem 58. The latter is attached to the end of a square rod 60 which in turn is attached by its reduced end 61 to a removable plug 62 (see Fig. 11). The hole 57, in conjunction with the automatic water-feed valve (the pressure-reducing valve previously described), affords means for controlling the admission of feed-water, and is adapted to produce normally a continuous flow of sul stantially fixed quantity to the boiler inlet, since the water-feed valve (the pressure-reducing valve) automatically maintains a uniform pressure for the water that passes through this hole of fixed size. Obviously, the same results would be obtained by substantially the same means, during the normalioperation of the machine, by restricting, at any other point, the duct leading from the chamber 40 in the water-feed valve to the boiler, to the size of the hole 57. But since this restricted passage, that measures the water into the boiler, is the only passage in the machine so small as to be in danger of becoming plugged by dirt in the water, it is desirable that it should be so located in the line that it is accessible, as shown in the drawings, and that the provision there described should be made for safeguarding it. When the water is first turned on, the water-pressure forces the piston 56 up in the chamber 52, against the pressure of the spring 59, till the stem 58 extends through the hole 57, and the piston comes into con tact with the lugs 63 on the rod 60. While the boiler is becoming heated the water flowing through it is not all converted into steam, but the stem 58, which partially fills the hole 57 when the water is first turned 011, causes water to flow to the boiler in less than the normal quantity until a sufficient pressure of steam is created in the boiler to overcome, in conjunction with the spring 59, the water-pressure, and withdraw the piston 56 from the stem 58 and force it down into its normal position shown in Figs. 9 and 11.

Though desirable, it is not necessary to provide for diminishing the flow of water to the boiler during the time that the boiler is becoming heated, because any water that may not be converted into steam during that brief time is collected into the separatorchamber 5, before it reaches the steam-jet, and subsequently is evaporated by the steam, which becomes superheated after the machine gets into operation. Indeed, it is desirable, even when means are employed for diminishing the flow of water to the boiler while the boiler is becoming heated, to give the boiler an excess of water in order to provide against the possibility of burning the boiler, and this is made possible by interposing between the boiler and the steam-jet a chamber like the water-separator 5, to receive the excess, but the less surplus water collected in the water-separator 5 the sooner it will be absorbed by the steam.

In addition to its function of diminishing the flow of water to the boiler when the machine is started, the stem 58 serves to dislodge from the hole 57 any dirt with which it may become clogged, for if the hole becomes clcgged the water supply to the boiler fails and the steampressure falls till the water-pressure sutliciently predominates to force the piston 56 up to the stem 58,Whereupon the stem dislodges the dirt, the flow of water is resumed to the boiler, the steam pressure rises to normal, and the piston 56 resumes its normal position. Thus, an automatic cleaner is provided for the one and only water passage in the machine that is liable to stoppage.

The control-valve 64: shown in Fig. 10 is adapted to regulate the gas. The gas is received into the said valve-chamber 66 through a connection (Fig. 9). The gas valve 6-1-v is connected with a diaphragm 67 by means of a stem 68, which passes through a chamber 69 (through which the gas is conducted to the burner), a. gland 70 and a chamber 71, the latter being connected with the boiler through the pipe-72, passage 53 and feed-pipe 55. A water-tightconnection is made between the chambers 69 and 71 by a rubber tube 73 that surrounds the stem 68. A spring 7% normally holds the gasvalve 6-l in closed position. The spring is compressed between a plate 75, that lies against the gas-valve 64;, and a cap 76 that is screwed into the end of the valvecasing. A nut 77, to which the gas-valve 6i is attached, is screwed upon the stem 68 so that the valve 6i can be adjusted on the stem 68 in order to regulate the quantity of gas that flows to the burner when the gas-valve is open, and is locked in position by the setscrew 68. \Vhen the water is turned on the pressure of the water in the chamber 40 of the pressure-reducing valve, against the diaphragm 67, opens the gas-valve 6% against the resistance of the spring 74, and gas flows through the connection 65, chambers 66 and 60 (Figs. 10 and 11) to the burnerring'79 whence it passes to the burners 80. Obviously the products of combustion pass from the generator-chamber up through the diffusing-plate 81 into the top of the machine, whence they pass to the chamber 11 where they mingle with the steam and fine particles of dust discharged into said chamber from the pipe 10, the dust being incinerated thereby. The pipe 72 and chamber 71 in the control-valve (Fig. 9) are always full of water, so that when steam is generated in the coils 1 it acts upon the diaphragm 67 and adds its force to that of the spring 74 to close the valve 64 and so reduce the flow of gas. As the steam-pressure rises the gas-valve 64 is gradually moved from its fully-open position till the steam-pressure completely overcomes the water-pres sure, and closes the gas-valve 6-1:, when the flame is maintained by a pilot-light 82 (Fig. 1) until the steam-pressure falls off and the gas-valve reopens under the water pressure.

In practice the water-pressure reducingvalve is usually adjusted to deliver water to the machine at a pressure lower than the lowest pressure that will at any time prevail in the water-service main, in which case water is delivered to the machine at uniform pressure.

An advantage of the combined use of an automatically-operating water-feed like that described above (which is adapted to feed a uniform quantity of water to the boiler regardless of fluctuations of pressure in the water-service main) with an automaticallyoperating control-valve for the regulation of the fuel supply (which is under the joint influence of the Water-pressure and the steam-pressure as described) is that the discharge of a uniform weight of steam from the steam-jet 7, under uniform pressure, is thereby secured, in which case the capacity of the machine for work is maintained constant. The water-separator chamber 5 assists in attaining this result if and whenever the gas is shut off by the control-valve momentarily, for then this chamber 5 serves as a compression tank. Another important advantage derived from the use, in the combination described, of a water-feed valve of the character described is that by adjust-' ing the tension of the spring 4A it is possible to obtain different results as to the degree of vacuum produced by the machine and the volume of air exhausted, and the quantity of fuel consumed, such as are usually obtained in other vacuum-cleaners by variations in size, proportions and capacities of the different elements, thus having, in a single machine, means for meeting differentdemands. In this connection it is onl necessary to call attention to the fact that as the water-pressure in the chamber 4C0 of the reducing-valve is made to vary, the steam-pressure maintained in the boiler will necessarily be made to vary correspondingly, so that substantially the same difference between the water-pressure and the steam-pres sure will be preserved, and that such being the case, the same quantity of water will normally be fed to the boiler through the 7 hole 57 of fixed size, the only difference being in the degree of superheat of the steam. lVithin a considerable range of adjustment these conditions prevail, beyond which it will be found necessary also to change the adjustment of the gas-valve 64.

The chamber 66 of the control-valve (Fig. 9) is connected to a manually-operated valve 83 (Fig. 5) by the connection 65 before mentioned. A by-pass 84 leads from the valve 83 to the pilot-light 82.

This valve 83 isprovided for the purpose of shutting oil the gas from the machine, with the exception of the pilot-light 82, whenever there is occasion to open the door 85 that gives access to the burners and pilot-light 82. On the stem of the valve 83, opposite its handle 86, is the, angular locking-piece shown in Fig. 8, whereby (1) the door is locked shut when the valve 83 is open, (2) the valve 83 is locked closed when the door 85 is open, and (3) the-pilot-light valve 87 is prevented from being shut off when the valve 83 is open.

It is necessary to close the gas-valve 83 before the door 85, can be opened, because when this valve is open (as shown in Figs. 5 and 6) the flange 88 of the lockingrpiece shown in Fig. 8 lies close in front of a lug 85 on the door 85 when the door is closed. This flange 88 is so long that it is not withdrawn from the path of the door till the gasvalve 83, has been fully closed, as shown in Fig. 7. The valve 83 is automatically locked in its shut-off position shown in Fig. 7 by opening the door 85 that gives access to the burners and pilot-light, by means of a latch 89 pivoted at 90 to a lug 91 on the casing 3. This latch has an arm 92 that is adapted to be engaged by the door 85 when the latter is in closed position and to be forced inwardly by the door, as shown in Fig. 5, against the action of a spring 93. T his latch also has an arm 94tthat is adapted to underlie the shoulder'95 on the looking-piece shown in Fig. 8, as shown in Fig, 7, when the, valve 83 is closed and the door 85 is open, soas to permit the spring 93 to force said arm 94: outwardly. Thus the valve 83 is prevented from being opened until said arm 94 is moved inwardly by closing the door against said arm 92. The pilot-light valve 87 is operated by a lever 96, which has an oppositely-extended arm 97 (Figs. 6 and '7) that is adapted to engage the surface 98 on the locking-piece shown in Fig. 8, when the pilot-light valve is open, as shown in Fig. 6. Before the pilot-light valve 87 can be shut oil", as shown in Fig. 7, it is necessary to turn the valve 83 till the recess 99 in the locking-piece, shown in Fig. 8, comes opposite to the arm 97 of the pilot-valve lever, and by so doing the valve 83 is closed. Furthermore, the pilot-light valve 87 is connected with the valve 54: in the water line leading'to the boiler, by the link 100 and arm 101, so that the water is shut off from the boiler if and whenever the pilot-light valve is closed. Accordingly, it is impossible to turn on the gas to the pilot-light, as a preliminary to lighting the pilot-light. without first turning off the gas to the burners, thus making impossible the escape of gas from the burners while an attempt is being gmadeto light the pilot-light; it is, also impossible toeXtinguish the pilot-light without shutting off the gasfrom the machine. thus making it impossible for gas to escape from the burners when there is no pilot-light burning to ignite them, and it is also impossible to flood the machinewith water by opening thestarting-valve when the pilotlight is not burning. The flow of gas from the pilot-valve 87 to the pilot-burner 82 may be regulated as desired without disturbing the valve itself. To this end a spindle 106 is screwed into the end of the valve 87 opposite to the handle 96, and this spindle has a reduced end 107 that is adapted to shut ofi' moreor less completely the duct 108 that leads to the pilot-tube 84. The outer end of the spindle 106 is slotted, so that it may be readily turned, and a stufiing-box 109 is provided to maintain it gas-tight. These features for guarding and locking the parts against accident, and for regulating the pilot-light, are not claimed herein, as they will constitutethe subject-matter of another application.

It is obvious that the quantity of water fed to the generator from a source of water supply under pressure is determined by the area of the most restricted passage leading into the generator and the effective pressure at which it flows through said passage. It is also obvious that a continuous flow of feedwater to the generator of substantially uniform quantity can be obtained from a source of water supply under variable pressure,

either by regulating the pressure or the area of the most restricted passage leading to the boiler. In said patent to Flynt, No. 1,037,884, two forms of water-feed valves are shown and described. In the form of valve represented in Fig. 3 of the drawings of that patent the flow is regulated automatically by a float valve that maintains a constant head of water back of the restricted passage leading to the generator notwithstanding variations in the pressure of the source of water supply. In the other form of valve represented in Fig. 5 of the drawings of that patent the area of said passage is varied automatically by subjecting the valve itself to the opposing pressure of the generator and water supply. In the machine hereinabove described a pressure-reducing valve is used that is also adapted to maintain a constant pressure of water back of the restricted passage or hole 67 leading to the generator. The result obtained from this pressure-reducing valve differs from that obtained by the use of the form of valve shown in Fig. 3 of said patent in that it is adapted to maintain the head of water back of the restricted passage leading to the generator constant at a lower pressure than that ofthe water service main, and yet at a pressure which is adequate to operate upon the control-valve to open the gas-valve and tubular boiler 1 is supported within the casing 3 so that it may readily be lifted therefrom after having disconnected it from the miter-separator 5 (Fig. 1) and the valve 54 (Fig. 9). To this end the boiler-hangers 2 are each provided at their upper ends with an offset lug 102, of greater width than the body of the hanger (Fig. 3). These lugs are adapted to rest on an inwardly-extending shoulder 103 (Fig. 1) that extends completely around the casing at its top. A vertical flange 104, also extending around the casing, integral with the shoulder 103, is provided with notches 105 at suitable intervals, and these notches are slightly greater in width than the hangers. but not as wide as the lug 102. lVhen the hangers are dropped into position (Fig. 3) they are prevented from falling into the casing by the engagement of the lug 102 with the outer side of the flange 104. and the bottom of the lug 102 rests on the ledge or shoulder 103. the latter suppo ting the weight of the hangers and the boiler.

I claim:-

1. A steam-generator compris ng, in combination. a continuous-flow boiler adapted to discha ge through a permanently-open orifice of fixed size. a rest icted passage normally of fixed size leading to the boiler, an automat c water alve. cons sting of a pressure-reducing valve adapted to receive water from a source of supply under variable pressure and to d scharge it through said restricted passage into the boiler at a uniform. reduced p essure. heat-producing means for heating the bo ler. and means for regulating the heat-producing means adapted to operate automatically to maintain a uniform pressure of steam in the boiler.

2. A steam-generator comprising, in combination, a continuous-flow boiler adapted to discharge through a permanently-open orifice of fixed size. a restricted passage normally of fixed size leading to the boiler,

means operating automatically to control the admission of feed-water, and adapted to convert a fluctuating water-pressure in a source of supply of water into a lower uniform pressure, heat-producing means for heating the boiler, and means, for regu lating the heat-producing means, adapted to operate automatically to maintain a uniform pressure of steam 1n the boiler.

3. A steam-generator comprising, in combination, a continuous-flow boiler adapted to discharge through a permanently-open orifice of fixed size, a restricted passage normally of fixed size leading to the boiler, adjustable means operating automatically to control the admission of feed-water, and adapted to convert a fluctuating waterpressure in a source of supply of water into a lower uniform pressure, heat-producing means for heating the boiler, and means, for regulating the heat-producing means, adapted to operate automatically to giaintain a uniform pressure of steam in the o1 er.

4:. A steam-generator comprising, in combination, a continuous-flow boiler adapted to discharge through a permanently-open orifice of fixed size, a restricted passage of fixed size leading to the boiler, a springcontrolled automatic pressure-reducing valve adapted to receive Water from a source of supply under variable pressure and to discharge it, through said restricted passage, into the boiler at a uniform reduced pressure, heat-producing means for heating the boiler, and means, for regulating the heat-producing means. adapted to operate automatically to maintain a uniform pressure of steam in the boiler.

5. A steam-generator comprising, in combination, a continuous-flow boiler adapted to discharge through a permanently-open orifice of fixed size. a restricted passage of fixed s ze leading to the boiler. a springcontrolled automatic press re-reducing valve adapted to receive water from a so rce of supply under variable pressure and to discharge it. through said restricted passage, into the boiler at a unifo m reduced pressure. means for adiusting the tension of said spring for different unifo m p essures. heatproducing means for heating the boiler. and means, for regulating the heat-prod cing means. adapted to operate automatically to maintain a uniform pressure of steam in the boiler.

6. A steam-generator comprising, in combination, a continuous-flow boiler adapted to discharge through a permanently-open orifice of fixed size, a restricted passage of fixed size leading to the boiler, an automatic pressure-reducing valve adapted to receive water from a source of supply under variable pressure and to discharge it, through said restricted passage, into the boiler at a uniform reduced pressure, said valve being open when the generator is idle, and normally open when the generator is in use, heat-producing means for heating the boiler, and means, for regulating the heatproducing means, adapted to operate autoin the boiler, toregulate the burner to main-' tain a uniform steam-pressure in the boiler. v 8. A steam-generator compris ng, in combination, a continuous-flow boiler adapted to dischargei through. a permanentlybpen orifice of fixed size, a restricted passage. of fixed size leading to the boiler, an automatic pressure-reducing valve adapted to receive" water from'a source ofsupply undervariable pressure and to deliver'it,'through said restricted passage, to the boiler at a uniform reduced pressure",-a burner for heating the boiler. and means adapted to operate, under the joint controland opposing actionof the uniform. Water-pressure created ='by the water-valve and the steam-pressure in the boiler, to regulate the burner to maintain a uniform steam-pressure in the boiler.

9. A steam-generator comprising,*in oombination, a continuous-flow*boiler adapted to discharge through a permanently-open" orifice of fixedsize,-a restricted passage of normally fixed size lea ding to'the' boiler, an automatic pressure-reducing valve adapted to receive water from a 'source'of supply under variable pressure and to discharge it, through said restricted passage, into the boiler under uniform pressure, a burner, for heating the boiler, adapted to be connected with a source of fuel-supply, fuel-valve for controlling the-admission of fuel 'to'the burner, an automatic actuator for said fuelvalve, which is subject to the opposing-pressures of the Water as delivered from said water-valve and the steam-pressure in "the boiler, be ng moved by the pressure of the Water delivered from said water-valve to' open said valve and to hold said valve open against the steam-pressure inthe boiler at a predetermined pressure less' than the re-;

duced water-pressure, and being moved to close said valve when the steam-pressure approaches the water-pressure. I I

10. Asteam-generator comprising, in combination, a continuous-flow" flash-boiler, a permanently-open steam-nozzle of' fixed size,

means adapted tdproduee normallya continuous flow of feed-water, of substantially uniform' quantity, v to the ,boi-ler-, means adapted I to, collect and. evaporate such sur-- boiler and steam-nozzle, means adapted to produce normally a continuous flow of water to the boiler of substantialiy fixed quantity, heat-producing means for the boiler, and means, for regulating the heat-producing means, adapted to operate automatically to maintain the steam-pressure in the boiler at a lower degree than the pressure of the water supply.

12. A steam-generator comprising, in combination, a continuous-flow flash-boiler, a

permanently-open steam-nozzle of fixed size, a water-separating chamber between said boiler and steam-nozzle, a restricted passage of fixed size leading to the boiler, an automatic pressure-reducing valve adapted to receive water from a source of supply under variable pressure and to discharge it, through said restricted passage, into the boiler at a uniform, reduced pressure, heat-producing means for heating the boiler, and means, for regulating the heat-producing means, adaptedto operate automatically to maintain a uniform pressure of steam in the-boiler.

13. The combination, with a continuousflow boiler, a device supplied with steam thereby, a burner for heating the boiler, and valve-mechanism, for controlling the burner and the flow of feedwater to the boiler, adapted to start the burner and the'flow of water simultaneously, of a water-receptacle interposed between the boiler and said device supplied thereby, the receptacle being of a capacity sufiicient to accommodate the water which passes unvaporized through the boiler before it has attained its normal working temperature.

14. A steam-generator comprising, in combi'nation, a boiler, a restricted passage leading-thereto, and means, located in the water line leading to said restricted passage, adapted to be operated automatically, by an excess pressure in the sourceof' water supply over pressure in the boiler, to 'remove dirt deposited in said restricted passage.

15. Asteam-generator comprising, in combination, a boiler adapted to receive water from a source of water supply under pressure, through a restricted passage, and means, for automatically clearing said restricted passageyconsisting of a part in which said restrictedpassage is located, movable under: the oppiosin gactionof the pressure inthe -water-supply and-thesteam-pressure in the boiler, and a fixed stem that, in one'position assumed bythe movable part under pressure from, the source of water-supply, is adapted to enter said passage, and means for heating the boiler.

16. A steam-generator comprising, in combination, a boiler adapted to receive Water from a source of Water-supply under pressure, through a restricted passage, and means, for automatically clearing said restricted passage, consisting of a part in Which said restricted passage is located, movable under the opposing action of the pressure in the Water-supply and the steampressure in the boiler, and a fixed stem that, in one position assumed by the movable part under pressure from the source of Watersupply, is adapted to enter said passage, a spring tending normally to hold said parts apart, and means for heating the boiler.

17. Asteam-generator comprising, in combination, a boiler adapted to receive water from a source of Water-supply under pressure, through a restricted passage, and means, for automatically clearing said restricted passage, consisting of a part in which the restricted passage is located, and a stem adapted to enter said passage, oneof said parts being movable, under the opposing action of the pressure in the water supply and the steam-pressure in the boiler, and the other said part being stationary, Whereby said stem enters said passage when the Water pressure overcomes the steam-pressure.

JOSEPH M. STABEL. Witnesses: I

O. 'S. DAVIS, D. GURNEE.

Copies of this patent may be obtained for five cents each, by addressing the f Commissioner of Patents,

Washington, I). G.

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