US1877983A - Explosion chamber - Google Patents

Description

Sept. 20, 19.32.

R. SCHILLING EXPLOSION CHAMBER Filed Aung. e. 1927' gl 353i 34 q 7d s n i It' L, l 0 I Z IB. l. I A@ I] Z g rij@ e l' 2 9 I l V all q y! I Vlr vn/Enron /TapqL'F-.Scf//LL//JG Patented sept. 2o,- 1932 Wren s'rAf'lflz's4 PArNr carica I RUDoLrH scHILLING, or Woonsrnn,y cALIoRNIA, AssIGNoR To HoILzwARrH GAS `'.IFURRINR co., or sAn rRANorsco, 'cAL1FoRNrA, A CORPORATION or. DELAWARE EXPLOSION GHAMRER 4Applicationiledv August 6, 1927. Serial No. 211,099.

The invention relates to explosion chambers suitable for use in combustion turbines .and lmore particularly to chambers of the indicated class in which coal dust is used as ,5,1 a fuel. `The, operation of such explosion chambers presents the problem of igniting the coal `dust with certainty in the relatively short interval of time which is available for this purpose and with regard to the relatively 10" low compression which iscommonly developed'i'n turbines of the designated type. The

objecteofvthe invention is to overcome this.

difficulty by spraying easily ignited fluid fuel in finely divided form into the combustion y1,6 chamber, in addition to the coal dust, and

in such a manner that the danger of premature ignition is avoided. The introduction of the fluidv fuel in accordance with'the invention, takes place after the introduction 29 of the coal dust. In this way any incandescent particles of coal dust or ash remainin 'from the previous explosion are extinguishe before the easily ignited fuel is introduced. Furthermore such introduction of fluid fuel 25 may take place with or without atomizing air and either through the same inlet with the coal dust or through an independent special inlet, as may be preferred. Other Vobjects will appear from the description hereinafter 3@ and the features of novelty will be pointed out in the claims.

a In the accompanying drawing, which illustrates an example of the invention without.

defining its limits, Fig. 1 is a diagrammatic fragmentary section showing a combustion chamber of a combustion turbine with the invention applied thereto: Fig. 2 is a fragmentary section, on an enlarged scale, illustrating the invention in detail;' Fig. 3 is a detail `view illustrating an actuating funit forming'part of the invention: and Fig. 4 is a vvierw,lpartly in section, of a distributor and interrupter for controlling the opening of the valves of the combustion chamber andfor timing the operation of the igniting elements.

lnI 1 an installation including the novel 'features is diagrammatically illustrated, which includes a representation of one of the combustion chambers v customarily found, 50 in a predetermined number, in combustion turbines of the type in question. yThe communication between the chamber v and the usual nozzle v is controlled in the customary;

manner by the conventional nozzle valve z and the usual electrically controlled spark plugs y or equivalent igniting devices are provided for igniting the fuel charge in the f well known way. A suitable form of timing mechanism is shown in Fi 4 which is substantially av duplicate of F1 4 of the patent to Hans' Holzwarth, No. 8 7,194. The dis-. tributor, which is indicated by the letter u, comprises a hollowY cylinder 28; a hollow revo lver29 which rotates withinand is spaced from the cylinder; a worm Wheel' 30 on lthe revolver shaft driven by a suitable motor (not shown) an oil pump 32; an oil tank 33; a pipe 34 leading from the tank to the pump; a back-flow oil pipe 35 from the controller cylinder to the tank; an annular passage 36 around the cylinder and communicating with it through anumber of ports; a pressure oil pipe 37 leading from the oil pump to the passage 36; a series of necks 38 on the revolver erating cylinders of the scavenging valves :v`

or,where the admission of the fluid fuel is effected with the aid of hydraulic mechanism, as described in said Patent No. 877,194, such pipes may be connected with theoperating cylinders of the fuel valves; athird series of y Yports 43`in the` controller cylinder; pipes a operative to place these ports in lcommunica- Ition with the operating cylinders of the respective noz'zle'valves.` a; a hollowv neck 45 on sal the revolver serving, as the revolver'turns, to

place itsj interior in communication' with the ports 39 successively, and thus admit fluid pressure to open the airvalves in succession; 'a similar neck-,46 cooperatingA with the ports valves one after the other.

'4:1 to open the scavenging valves in succession; and a similar neck 4:7 cooperating with the ports 43 to ei'ect openin of the nozzle i en the necks 45, 46, 47 move out of registry with the 1espective ports, the respective pipes .2 are relieved of pressure by the disc arge of the pressure fluid from such pipes into the annular space between cylinder 28 and revolver 29, from which space the Huid flows through pipe 35 to tank 33. The interrupter may take the form of a ixed annulus upon ,whlch are arranged a plurality of contacts 50, one for each cylinder, each contact being connected to the secondary of induction coil 49 by a wire 53, the other terminal of the secondary being connected by a wire 52 to a brush which en gages the shaft and is thereby electrically connected with an interrupter wiper 51 mounted upon the shaft and rotatagle therewith to engage the contacts 50 in succession, thereby closing the secondaries of the induction coils and operatin the spark plugs y in succession through t e wires y leading from the primaries of the induction coils. The construction further includes the usual valve for controlling the admission f scavenging air to the combustion chamer fv.-

In the novel arrangement, the combustion chamber c of the engine is provided with a projecting,hollow casin g in which a tubular member a is axially tted said member a including an inner circular flange a which projects into the combustion chamber v as shown in Fig. 2. At the baseof the ange a the member a is formed with a valve seat b with which an air valve b is arranged to cooperate to control the communication between the interior of the member a and the combustion chamber v. The'valve b comprises part of or is carried by a stem c connected with a piston e slidably mounted in a chamber e formed in the member a at the y outer end thereof and closed by means of a cap f as shown in Fig. 2; the piston e includes a stem e2 located in axial registry with the valve stem c and projecting outwardly beyond and slidable in the cap f. The valve stem 0 carries a plurality of external disks c' projecting radially outward in registry with annular recesses a? formed on the interior surface of the member a, said recesses a2 bein located in spaced relation to each other an each converging toward the valve seat b as shown in Fig. 2. The valve stem c is provided with an axial channel n which is continued through the piston e and piston stem e2 and has its outer end in communication with a pipe n leading to a fuel pump o as illustrated diagrammatically in Fig. 1. The inner end of the channel n terminates in a valve seat for the accommodationof a spring pressed fuel valve Z whereby the communication between the channel n and a chamber b2 newness formed within the cylindrical valve body bf is controlled. A plug d closes said chamber 'b2 toward the combustion chamber /v and is provided with restricted passages d2 which diverge toward the combustion chamber c and establish communication between the latter and the valve chamber b2.

The member a includes a port a3 which registers and communicates with a passage s formed in the casing gand terminating at its outer end ina flat surface with which the casing g is provided. A control slide L is slidably mounted on the aforesaid fiat surface and is maintained in position thereon b means of a yieldingly aiiixed cover i whic carries a hopper t for containinga supply of coal dust. The hopper tis in constant connection with a port z" of the cover z', and the slide h is provided with an opening h movable into and out o f registry with the port z" to thereby control the connection between the hopper t and the' interior of the member a by way of the passage s and the port a3. The control slide h is slidably reciprocated by means of a bell-crank lever lc carrying a roller 7c in engagement with a cam m fixed upon a suitably driven shaft Z and by means of a spring p. ln addition to the parts so far described the interior of the member a is connected by means of a passage r with a pipe fu which in turn leads to a source of air under pressure; a branch connection t connects the pipe 0 Fig. l withI the hopper t so that the pressure therein equals that within the member a, and the latter pressure accordingly does not resist the passage of the coal dust from said hopper t to the interior of said member a. AAn inclined inlet g is formed in the cap and leads from the piston chamber e to a pipe g which in turn is connected with the oil controller u, whereby the admission of oilunder pressure to the piston chamber e is automatically controlled for the purpose to be more fully set forth hereinafter; the controller u is also connected with the scavenging air valve m for controlling the operation thereof in the well known way. It will be understood that the mechanism shown and described is, in practice duplicated in an operative combustion turbine in the form of a plurality of units which operate in a predetermined manner 'to produce the desired sequence of operation in the complete turbine.

The operation of the structure so far referred to is as follows: As long as no pressure oil is forced into the chamber e behind the piston e the latter is vmaintained in its rearmost position by the air pressure which exists within the member a throughthe connection 1'; the valve b is accordingly held in its closed 'position against the seat b. As soon as pressure oil by the actionof the oil controller u is permitted to pass through the pi e g" and ort g the pressure will become e ective in 1n the chamber e and will accordingly'force the piston e to the left in Fig. 2,` it being understood that the pressure of the aforesaid oil is in excess lof theair pressure within the bustion chamber o.' As the aforesaid air passes from the member a it flows through the annular space between the circular inner surface of the extension a and the outer surface of the valve body b3 and is formed thereby into a tubular stream of air which enters the combustion chamber in this'form. `While the air is being charged a predetermined measured charge of highly iniammable liquid is forced throughl the pipe n by the action of the fuel pump o into the channel n of the valve stem c; lthis liquid fuel forces the valve d to an open position against the tension of its spring and passes into the chamber b2 and through the divergent channels d2 into the tubular stream of air flowing out of the extension a. The diver ent streams of liquid fuel passing into the tu ular stream of air bring about a thorough mixture of'fuel and `air which passes into the combustion chamber as previously set forth. Shortly before the opening of the valve b,'the port k of the control slide h is brought into registry with the port z" and the channel s and thus permits a measured charge of coal dust to pass from the hopper t into the interior of the member a; it will be understood that the control slide la is continuously reciprocated by the action of the cam m, the bell-crank leyer k and the spring p, the reciprocation being so timed and the port y71, being so located that the aforesaid introduction of a measured charge of `coal dust intothemember a will take place at the desired moment. This charge of coal dust is picked up by the air within the member a and the coal-dust-laden a1r, by impact with the projections c', is whirled about and thoroughly mixed and passes into the combustion chamber o. In the combustion chamber o, at the proper moment, ignition of the mixture of air and oil takes place first and causes ignition of the coal dust particles and thereby brings about an explosion in 'said combustion chamber, the

products of the explosion passing through an'- open nozzle valve z into and through the nozzle o to 'a place of use, for example against the rotor blades of a turbine in the customary manner. The aforesaid operative steps are repeated in proper sequence throughout any given period of operation of the turbine and result in a continuous operation y.of the turline wheel during such period. YIt will be understoodthat the nozzle valvesl is opened at the proper instant following an explosion,

` for example by the distributor u in' the manner disclosed in the above-mentioned patent to Holzwarth, No. 87 7 ,194.

Inasmuch as the ignition'oil' is generally more expensive than the coal dust and as only a small quantity of such oil is suicient to; properly igni-te the' aforesaid charge of coal dust, it is advantageous to operate under all load conditions with an equal but least possible quantity of ignition oil and to regulate only the amount of injected coal dust. In the illustrated example this is accomplished by providing a cam of inclined form as shown in Fig. 3 and mounting the same V.by means of a sleeve m adj ustabl upon' the shaft Z or a suitable part thereof by means of a key and a keyway as shown in said Fig. 3. Obviously by adjusting the sleeve m and with it the beveled cam m in axial directions, diferentportions of the active surface of the cam lml may be made effective upon theroller of the bell-crank lever if: whereby the throw of the latter and `as a result the extent of reciprocation of the control slidey L are varied to bring the port L, and consequently the channel s, more or less completely into registry with the port i In this way the. amount of coal dust charged into the member a may be varied. s

i The oil controller u, through the pipe g supplies the oil pressure for operating the piston e to open the valve b and also controls the supply of oil through the pipe vyhereby the valve m is opened to admit scavenging air to the combustion chamber v at the proper time. The uncontrolled oil pump o driven by means of a cam o located upon the shaft Z (see Fig. 3) forces a definite amount of ignitionl oil through the pipe n into the channel n at the proper time. In order to provide the desired correlated operations of the oil controller u and pump o these two elements are connected by means of a chain u to operate in proper unison. The connection t from the air supply o to the hopper t creates a pressure in the latter corresponding to the pressure exerted withinthe member a and thereby prevents the latter pressure from interposing a resistance to the entrance of the charge of coal dust at the proper time. I

Various changes in the specific form shown and described may be made within the scope ofthe claims without departing from the spirit of the invention.

I claim: g 1.- The combination with an explosion chamber, of a hollow valve member communicating with said chamber and provided,

municating-with said chamber and provided' with a valveA seat, a circular extension pro- ]ectlng from 'said member into said combustion chamber, a connection for introducing air under pressure into said member, a valvev cooperating with said valve seat to control the passage of said air :from said member into said circular extension, a circular valve body carried by said valve and cooperating with said circular extension to form the air into a tubular stream; a valve stem carrying said valve and provided with an axial channel, a piston connected with said stem, a pressure oil connection for directing oil under pressure against said piston to open said valve; means for forcing a supply of ignition 'luid through said channel, a plug connected with said valve body and provided with divergent channels for directing divergent streams of ignition oil into said tubular stream of air for mixture therewith, a hopper for containing a supply of coal dust, a connection from said hopper to the interior of said valve member, al control slide controlling said connection 'and an adjustable cam for controlling the operation of said slide.

3. The combination with an explosion chamber suitable for use in explosion turbines, of mechanism arranged to introduce a coal dust and air suspension under superatmospheric pressure intermittently into said chamber to ill the same, means for operating said mechanism intermittently, a valve at the inlet side of said chamber for separately charging an easily ignitable fluid fuel directly into said chamber, means for operating said luid fuel valve in such time relation to the operation of said mechanism that the admission of fluid fuel be 'ns after the admission of coal dust hasV egun, means for igniting the mixture, whereby an explosion at constant volume is produced without the performance of work in said chamber, and a nozzle valve at the opposite outlet end of said chamber operable to discharge the explosion gases from the chamber to perform their work outside such chamber.

4. The combination with an explosion chamber suitable for use in explosion turbines, of a hollow valve member communicating with said chamber and provided with a valve seat, a connection leading from the interior or said member to a source of air of higher than atmospheric pressure, a container for coal dust communicating with the in-V terior of said member, anair valve cooperating with said seat to control the communication between the interior of said member and said chamber, means whereby said air valve is intermittently operated at predetermined instants to ll said chamber with a coal dust and air suspension, valve mechanism at the inlet side of said chamber for separately admitting ignition oil directly into said chamber, means for operating said oil valve mechanism in such timed relation to the operation of the air valve that the admission of oil begins after the admission of coal dust has begun, means for igniting the mixture, whereby an explosion at constant volume is produced without the performance lof work in said chamber, and a nozzle valve at the opposite outlet end of said chamber operable to 'discharge the explosion gases from the chamber to perform their work outside such chamber.

5. The combination with an explosion chamber suitable for use in explosion turbines, of a hollow valve member communicating with said chamber and provided with a valve seat, a connection leading from the interior of said member to a source of air under higher than atmospheric pressure, an air valve cooperating with said seat to control the communication between the interior of said member and said chamber, a container for coal dust arranged to discharge into said hollow valve member, an intermittently operated valve controlling such discharge, means whereby'said air valve is intermittently operated at predetermined' instants to ill said chamber with a coal dust and air suspension, valve mechanism at the Y.

inlet side of said chamber for admitting ignition oil directly into said chamber, means for operating said oil valve mechanism in such timed relation to the operation of the air valve that the admission of oil begins after the admission of coal dust has begun, means for igniting the mixture, whereby an explosion at constant volume is produced without the performance of work inI said chamber, and a nozzle valve at the opposite outlet end of said chamber operable to discharge the explosion gases from the chamber to perform their work outside such chamber.

6. The combination with anv explosion chamber suitable for use in explosion turbines, of a hollow valve member communicating with said chamber, a connection leading from the interior of said member to a source of air of higher than atmospheric pressure, a container for coal dust arranged to discharge into said hollow valve member, a coal dust valve controlling such discharge,

mechanism for intermittently operating said rchamber to explosion chamber,.means for intermittently feeding an-operating 'iiuid to said last-mentioned valve to open the same at predetermined instants to lill said chamber with a) coal dust and air suspension, valve mechanism at the inlet side of said chamber for separately admitting ignition oil directly into said chamber, means for operating said valve mechanism 'in such timed relation to the operation .of Vthe air valve that the admission of oil begins after the admission of coal dust has begun, means for igniting the mixture,4 whereby an explosiony at constant volume is vproduced without the performance of work in said chamber, and a nozzle Valve at the opposite outlet end of said chamber operable to discharge thel explosion gases .from the perform their work outside such chamber.

7. The improvement in the art of generating power which comprises intermittentlyintroducing a mixture of air and solid -iuel into a combustion space of constant volume, charging a fluid fuel into said combustion space after the introduction of the solid fuel has begun, whereby such iiuid fuel is protected by the preceding body of air and solid fuel against premature ignition by the hot residual gases `and glowing fuel particles remaining 1n the combustion space 'from the previous explosion, igniting the mixture while the combustion space is com letely closed, so that combustion gases of hig pressure are produced, discharging the gases fromsaid space and converting the energyy thereof into mechanical energy.

In testimony whereof I have hereunto set fmy hand.

RUDOLPH SCHILLING.

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