US2685480A

US2685480A - Ash removal apparatus

Info

Publication number: US2685480A
Application number: US82341A
Authority: US
Inventors: Charles K Birch
Original assignee: Lehigh Valley Coal Sales Co
Current assignee: Lehigh Valley Coal Sales Co
Priority date: 1949-03-19
Filing date: 1949-03-19
Publication date: 1954-08-03
Anticipated expiration: 1971-08-03

Description

Aug- 3, 1954 c. K. BIRCH ASH` REMOVAL APPARATUS Filed Maron 19, 1949 INVENTOR. ham/es /f z'rc M uw MMV/3mm ATTORNEYS Patented Aug. 3,` 1954 ASH REMOVAL APPARATUS Charles K. Birch, Montclair, N. J., assignor to Lehigh Valley Coal Sales Company, New York, N. Y., a corporation of Delaware Application March 19, 1949, Serial No. 82,341

2 Claims. 1

This invention is directed to the provision of improved ash removal apparatus for transferring ashes from a coal-fired furnace to an ash recep-\ tacle located at a distance from the furnace. The new apparatus makes use of a suction system for effecting transfer of the ashes from a hopper beneath the furnace to the ash receptacle. Suction systems for ash removal have been proposed heretofore, but have not been generally accepted for use in connection with small furnaces such as household heating furnaces. A careful study of the capabilities and limitations of suction systems has led me to the conclusion that such systems are in principle sound for eliminating the hard and dirty job of removing ashes by hand from a coal-red furnace; but for the system to be practically useful special provisions must be made to prevent clogging, and the system must be essentially automatic in its operation in order for it to be suitable for widespread use, and especially-for use with furnaces for household heating and with other furnaces operated by mechanically untrained persons. Lack of effective provisions to accomplish these ends have been responsible for the indifferent success of the suction systems for ash removal heretofore proposed.

The ash removal system of the invention is particularly designed to minimize any opportunity for clogging, to be quiet and clean in its operation, to be essentially automatic, and to be constructed at a cost making it attractive for use in conjunction with household heating 'furnaces and other small coal-fired furnace installations. tion comprises a coal-fired furnace having an ash crushing grate provided with the usual grate shaking lever, which in turn is equipped with a removable shaking lever handle. An ash hopper is mounted vbeneath the grate to receive ashes shaken therethrough. A suction box is connected to the bottom of the hopper, and the hopper serves to direct the ashes into it. The suction box is connected by a suction pipe to an ash separator detachably mounted on an ash receptacle located at a distance from the furnace and in which the ashes ultimately are collected. A suction fan, preferably mounted directly on the ash separator, is arranged so that its inlet is connected therewith. Its outlet may be connected to a discharge vent or flue, or may be connected to a dust'filter, or may simply'open directly to the atmosphere. The fan is driven by an electric motor which preferably is energized through a switch mounted adjacent the grate The complete apparatus of the inven- A shaking lever and connected in circuit with a motor and with a source of electric power. If such a switch is used, means for closing it are mounted on the grate shaking lever in position to be engaged and actuated by the removable handle whenever the latter is attached to the grate shaking lever. Thereby whenever the handle is applied to the shaking lever, the fan motor is automatically energized and creates a flow of air from the ash hopper through the suction box and suction pipe to the ash separator. Shaking the grate crushes the ashes as Well as causing them to fall into the hopper, whence they are carried in the air stream through the suction pipe to the ash separator. There the coarse ashes separate from the air stream and settle into the receptacle. Thus the system is automatically set in operation and the ashes are transferred to the receptacle by the simple steps of placing the handle on the grate shaking lever and shaking it in the usual manner.

The design of the grate is of importance to the operation of the system as a Whole, for it must be capable of crushing whatever ashes pass through it, when it is shaken, to a size ne enough so as not to cause clogging of the suction system. Also of importance to the operation of the system as a whole is the design and construction of the suction box at the bottom of the hopper. Even fine ashes tend to accumulate at this point and cause the suction pipe to become clogged; but I have found that by providing a suction box of proper design at the bottom of the hopper, to which the suction pipe is connected, clogging can be virtually completely prevented. Furthermore, the provision of a suction box permits the suction pipe to extend laterally from it, rather than vertically down from the hopper, and so greatly decreases the head room required below the grate for installing the system. The arrangement of the suction fan and ash separator directly over the ash receptacle renders operation of the system clean in the building within which the furnace is located by making the entire system within such building, up to the ash receptacle itself, operate under a reduced pressure and so prevent the possibility that leaks in the system will result in ash dust being discharged into the building atmosphere. Also by this arrangement the noise incident to operation of the fan is produced at a point where it is not objectionable.

The foregoing and other features of the new apparatus are described more in detail below with reference to the accompanying drawings,

which show a preferred embodiment of the new apparatus and in which Fig. 1 is a more or less diagrammatic View, partially in section, of an ash removal system according to the invention; and

Fig. 2 is a plan view looking down on the ash hopper of the furnace of Fig. l.

The :ash .removal `apparatus of the invention is shown-in Fig. l in "combination with a coalred furnace I0. The furnace is provided with a grate I I on which the coal is burned. A grate shaking lever I2 iitted with a removable handle I3 is provided for shaking the grate and thereby causing the ash to drop into ahopper IES mounted directly beneath the grate. connected to the bottom of the hopper, fand -one end of a suction pipe I6 is rin .turn `connected to the bottom of the suction box. The other end of the suction pipe connects with "an fasli separator Il' detachably mounted on an ash receptacle IS. In most installations fthefash :rerceptacle will :belocated-:at a distance fromzand ,fat .fa :higher level :than the :furnace 1:0. A 4fan :I9 fis xmounted over :the `Vash separator, with its inletconduit -26 connected with the `interior 'of the separator. The routlet :conduit `2I irornthe :fan oisfcomiected to f-a zdischarge vent Aor ue22,

: tormay-alternatively:benonnected'to a dust filter tbag, :or :even :beopen to the atmosphere. The :fan: is :driven-thy an'electric'motor 23.

'When .the :fammotor ,23 is energized, ythe fan draws air from ,the hopper I4 through-thezsucrtiontbox 'I5 and suctiongpipe it into :andzthrough 'fthe :separator ;I;'I. Ash delivered through the grate YII :when the latter shakenfis collected :in the current :of air'xin the :fsuction 'ibox Aand `is transierred thereby to zthe separator, wherein almost :all ,of fthe v:ashzseiftles :out Yand drops :into fthe :receptacle zIS. 'The small amount fof :iine :ash vparticles that .do gnot :settle are l:carried :in the air stream through :theifanandpthroughgits @outlet fnonduit :2i to 'the :discharge 'vent ':22. 'The :air escapesthrough .the f .pores of the iilter abag `to the atmosphere AItrissfiecessary:thattheashcentering'thehopper Y :|14 be nely :enough divided so :as :not to clog :the fsuctionzbox :It orfthe :suction "pipe I6. .Accord- I'ingly, the .grate .I:I iis idesigned to :crush vzthe .ash :passing through it into :the fhopper. An adxvantageous form :of sgratepisfshowncinr my-.copend- .ing :application :Serial No. 4185,001), .-riled Septem- :ber 15,11950.

The ash =hopper :I4 .is supporteddirectly :below the 'grate '.-ifI onbrackets '.30 .fastenedto the :furmace structure. rlhe ihopper is deined :by asub- .fstantially plane -front .wall FBI, :a vsubstanti-ally plane .rear :wall 32 anid. substantially `plane :side 'walls 33,1'all1of which awalls'` slope inwardly :and rdmvnwardly'tow-ard each other. `Thesuctionliox 55:5 .atpthe "bottom :of Jthe 'hopper :is `most advan- 'tageously ormedby extendingtheffront wall RBI andiside '-.walls v33 fof .the ahopper :substantially in their :respective planes downwardly `:to Ya ibottom apex Bdfbeneath the zbottomof the fhopper itself bottom .of fthe hopper zis Adernarked .by the A'lower'edge' 3'5 of 'the zhopper'rear wall .32) The y:rearfwall 3.6 .of the .suction box (as best shown :in Eig. `1) nis curved .concavely'toward the front 'wall .,i. fe. lits lower Aportion `near the `suction .xbox :apex lbcurvesupwardly andfaway-from the :front wall, and its .upper portion curves .back again toward the front wall and joins with fthe ,rear wall 32 `of the .hopperat its .lower edge 35. .Thus the rear .wallof the ,suction .box approaches .the .front 4wall thereof .more closely at its upper edge than at its mid-portion, and the maximum distance between the front and rear walls of the suction box occurs substantially midway between the top and bottom edges of such rear wall. The suction pipe I6 is connected to the front wall of the suction box I5 near its bottom apex, and extends laterally therefrom at an acute angle thereto.

I have ifoundithat the-provision of 'a suction box I5 is of importance to prevent clogging of :the suction system. If the suction box is omitted .and .thesuction pipe is connected directly to the bottom of the hopper (especially if it extends hlaterally therefrom), the ash that collects at the -.bottomfof thehopper tends to clog the entrance to-the suctionpipe. It is my present belief that .whenasuctionbox as described above is provided, it has the effect of so directing the current of air :created by the suction fan as to avoid or minimize any regions of low air velocity in which :ash :particles @tend lto settle out .and collect in a :pipe-,clogging mass. A.In :any event, .the 3pm- :vision :of the suction fbox is 'of- 'distinct advantage, tboth 'for :its -eiect -in :preventing clogging zand :because it .enables the suction :pipe :to vextend laterally from beneath :the .-furnace, thereby minimizing the space required lbeneath'thegrate :for freaking the installation.

The ash separator :H to -which :the-other --end roi the :suction pipe :I5 wis connectedLis 4simply a chamber, `preferably cylindrical, v.closed at the tcpandiopen at-the.bottom. A ange' Visprovided; aboutV its `lowergperipliergy for: engaging with the upper edge :of -the ash receptacle 4:8. The :flange :may -be lined with gasket material to .'Iacilitatemakingaftight jointr with :the receptacle. The: ash separator .may .be permanently mounted in position, and thefashreceptacle. may be carried en -.a vertically .imovableplatform .that Imay :be raisedto bring the upper edge of the :receptacle into engagement with zthe .flange :t3 to :form a .substantially pressure-.tight joint during f normal use of theapparatua :and that may be lowered 'when :desired through the distance of several inches necessary to permit withdrawal of .the receptacle -when it is tiine :to empty it. fAlternatively the ash receptacle may besetnza `rigid foor .and fsome `'special provision may be :made fon-raising .and lowering Ythe -ash separator, :or sthefseparator .may .merelymest ori-,the receptacle, fto tbe .manually .raised andflowered.

The-fan-inlet conduit 20, which is open atits lower end, extends 'axially into :the ash separator through 'its :closed 4top and projects preferzably-to-a point near its open fbottom. Thesu'c- :tionulipe I6, on the otherhand, is preferably connected :to the side of `the*ash:separato1.:near.its top. Theseparatortprovides.a substantial fenflargement `in the suction system, Vin whichzthe velocity :of the :air :current `created .fby `the fan fis:low'-and in whichash particles carried `by the fourrent of air .are'consequently given an 'oppor- Atunity to Vsettle out and Afall-.into the ash receprltacle. Generally it .is advantageous to connect l the l'suction pipe 'L6 'tangentially .rather -than radially fto the ash separator, :so that the fdirection fof air ow through thesseparator ismore :or .less circular. Thisresults 'in imparting fa centrifugal A'force :to the ash "particles and :thereby :promotes `their separation .'from the current of alr.

The ,fan :I9 is .of conventional construction. Whatever 'very :fine ash -does :not settle -ou-t `in .the separator VI Tl (and it :is quite small imamount) is carried rby `the -,current of air v:th-rough 1.the .fan

and is discharged through the vent 22. In some cases the vent 22 may be dispensed with and the fan outlet may discharge directly to the atmosphere. In other cases where conditions require catching even the very small amount of fine ash that does not settle in the separator, a filter bag may be attached to the fan outlet conduit 2|.

In a typical installation of the new apparatus in combination with a household heating furnace, the furnace itself is located in the basement of the building, and the ash receptacle, the separator, and the fan are located some distance away at ground level, whence it is relatively easy to carry away the ash receptacle, when it is full, for the purpose of disposing of the ashes.

In order to minimize any opportunity for clogging of the system, it is important to tranfer the ashes to the receptacle substantially as soon as they are passed through the grate into the hopper, and to avoid having them collected and stored, even for but a short period of time, in any part of the system between the grate and the receptacle. This involves making provision to operate the fan whenever the grate is shaken. A convenient way to accomplish this result essentially automatically is to actuate the motor 23 (which drives the fan) through a normally open switch which is closed (to set the fan in operation) when the removable handle i3 is placed on the grate shaking lever I2.

It is evident from the foregoing that the ash removal system of the invention is of uncomplicated construction, is easy to install, and is substantially automatic in its operation (i. e. it requires no manipulative steps beyond those normally involved in shaking the grate of a coal-fired furnace). It has also been found in use to be effective for removing ordinary coal ashes from a furnace to a receptacle remote from and at a substantially higher elevation than the furnace itself; and it has proved to be reliable and dependable. It therefore provides a practical means for eliminating the most objectionable feature incident to the operation of small coal-fired furnaces, namely, the removal by hand of the ashes.

I claim:

1. In ash removal apparatus of the character described, an ash hopper, a suction box connected to said hopper at the bottom thereof and having side Walls and a front wall inclined downwardly to a bottom apex, an ash removal suction pipe connected to and extending substantially laterally from the front wall of said suction box at the bottom thereof and at an acute angle thereto, the suction box having a closed rear Wall the lower portion of which extends to the bottom of the suction pipe and curves away from the front wall and the upper portion of which curves back again toward the front wall, the maximum distance between the front wall and rear wall being at a point below the top edge of said rear wall and above the bottom apex of the suction box.

2. In ash removal apparatus of the character` described, an ash hopper having substantially plane front, side and rear walls all sloping downwardly toward each other, said front and side walls being extended substantially in their respective planes to below the bottom of the hopper and forming the front and side walls of a suction box having a bottom apex and connected to said hopper at the bottom thereof, and a closed rear wall for said suction box joined at its upper edge to the lower edge of the hopper rear wall, the rear wall of the suction box being curved concavely toward the front wall thereof and extending to the apex of the suction box, the maximum spacing between the front and rear walls of the suction box being approximately midway between the top edge of said rear wall and the bottom apex of the suction box.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,320,898 McGuire Nov. fi, 1919 1,322,361 Sherman Nov. 18, 1919 1,355,508 Roever Oct. 12, 1920 1,511,018 Fuller Dec. 14, 1926 1,833,853 Patrono et al Nov. 24, 1931 1,887,768 Maloney Nov. 15, 1932 2,234,788 Williams Mar. 11, 1941 2,239,010 McMillan Apr. 22, 1941