US2183274A - Apparatus for treating loose flowable material - Google Patents

Description

Dec. l2, 1939. F. H. BARNSDALE APPARATUS FOR TREATING LOOSE FLOWABLE MATERIAL Filed JulyV 25, 1937 4 Sheets-Sheet l f fills Dec. 12; A1939. F. H. -BARNSDALE APPARATUS Fon TREATING LoosE FLowABLE MATERIAL File'd July 25. 1937 4 Sheets-Sheet 2 WHH.W\\\ W///// Tim/ i {i} IWIL K nml@ y .V/ m E l2, 1939. F. H. BARNSDALE APPARATUS FORl TREATING LOOSE FLOWABLE MATERIAL Filod July 23, 1937 4 Sheets-Sheet 3 Dec. 12, 1939. F, BARNSDALE 2,183,274

IAPPARATUS FOR TREATING LOOSE FLOWABLE MATERIAL y Filed July 23. 1937 r4 Sheets-Sheet 4 Patented Dec. 12, 1939 l j UNITED STATE This invention relates PATENT oFFici.

APPARATUS FOR TREATING LOOSE FLOW- ABLE MATERIAL Frederick Herbert Barnsdale, Bristol, England, assignor to Arnold Redler, Stroud, England Application July 23, 1937, Serial No. 155,352

In Great Britain July 23, 1936 8 Claims.

to improvements in apparatus for treating loose flowable material,

such as grain, maize,

ance. In particular it is minerals in somewhat like. For many indusoften desirable to maintain a proper relationship between time and temperature, and to cook for a long time, say

one hour upwards. It

is also often of great importance to treat somewhat fragile material,

5' and a particular example with which the invention deals is the cooking of whole maize by steam.

The invention seeks to provide apparatus which v will supply the above requirements. The invention is concerned withthe known type of apparatus for treating loose fiowable material, such as grain, maize, minerals in somewhat small particules, or the like, in which the material is allowed to fall under the influence of gravity through a bin or tower by transverse members. posals the material was state and interruption packing or building up and its fall is impeded In some previous proallowed to fall in a free of delivery resulted in of the material at the bottom with resulting absence of uniformity and diculty in controlling other desired factors.

charge from the bin or movement of the material.

tower ensures uniform With any intermittently operating discharger, or any hopper bottomed discharger (such as have been proposed with filled bins for treatment processes) no uniform flow of material can be ensured as coring and avalanching occurs. AThe invenlses let, discharge the material absolutely uniformly and evenly.

According to the pr esent invention, apparatus of the type specified has the transverse elements so spacedr and numbered as to result in a substantially equal distribution of pressure of the material during its downward passage by retaining or supporting the material at a 5 It may. be arranged that the supply of material to the top of the bin or tower and discharge from the bottom is controlled by a speed control which is vresponsive to the ultimate demand or consumption, by virtue of conveying apparatus which returns unconsumed material, this unconsumed material being measured by means which alter the speed control. In constructing apparatus for use with materials which expand during treatment, in order to ensure uniform rate of travel through the bin it may be arranged that thelatter has downwardly uniformly diverging walls. Alternatively to ensure uniformity of flow and of pressure within the bin the latter may be formed with parallel sides, with the transverse elements uniformly diminishing inv width from the top to bottom of the bin.- Conveying apparatus for effecting the uniform and continuous discharge of material from the bottom of a bin and operating onA the en masse principle has been known for many years, in which there is a dischargingdevice for flour or other substances of a flowable nature, which device comprises chain-like elements adapted to be continuously driven. A preferred. form of the apparatus for the cooking of whole maize by steam is illustrated diagrammatically in the accompanying drawings together with modifications vof its parts.,

In the drawingsv Figure 1 is a vertical section across the treatment bin; f

Figure 2 shows the general arrangement schematically;

Figure 3 on enlarged scale tion shows a treatment (steam or gas) pipe in relation to a transverse element;

and in partial -secl Figure 4 is a vertical section across an alternative treatment bin;` and Y Figure' shows diagrammatically a speed control system employing a photo-electric relay.

Referring to the apparatus shown in Figures 1-3 the bin, which is preferably of square crosssection, has side walls I which diverge downwardly to allow for swelling of the material and thereby to ensure a uniform rate of travel. It is open at'its upper end 2 and across its bottom end has a sloping series of transverse members 3 spaced apart and forming a uniform escape, through openings 4, of material. The openings 4 allow flow of material on to a conveyor floor 5, across which moves an "en masse conveyor chain represented at 6 which is an endless chain with its return run at 6A. 'Ihe direction of conveyance is shown by the arrow 6B, and it is seen that this corresponds with the slope of the series of members 3. Across the bin are fixed a large number of spaced members 1 each of which is an angleiron arranged with inverted V-secton, secured to the walls I by lugs IA formed at their ends. Each member 1 shelters within and below itself a steam or gas pipe 8 with holes 8A for emission. The pipes 8 are mutually connected by supply pipes 9 having if desired, hand control valves 9A. All pipes 8, 9, are supplied by a distribution main pipe I0 from a boiler or other source.

The chosen form of the members 1, and their spacing, in particular their arrangement in transverse planes which are vertically spaced and so that the gap between any two nearly always had one other symmetrically above and one other symmetrically below, is such as to give the effect that, if maize or like owable solid be lled into the bin, it will be at substantially uniform pressure throughout, and will descend uniformly if some be withdrawn from the bottom, being thoroughly rotated and mingled on its way downwards. Moreover the even distribution of the pipes 8 ensures uniform treatment throughout the mass of material. Escape of material through the spaces 4 depends on the material being moved away by the conveyor 6; if no material were removed, none could flow down the bin, even though there might be a channel of escape along the direction of the conveyor such as a liquid could take. l

The control means can now be understood (see Figure 2 in particular). The conveyor chain 6, 6A, is driven by a terminal sprocket 6B on a shaft which is driven by a belt 6C from a main shaft I I of a gear box I2 (for varying the driving ratio) which is powered through belt I3 by electric motor I4.

The shaft II also drives, through belt I5, a centrifugal governor I5A which regulates the delivery of steam through the pipe I0. Shaft II also drives, through belt I6, a worm or Archimedean helix feeding device IGA (and a wheel IBB for feeding water to the material just before it is fed into the bin by device IBA if some humidity be required).

The speed of the motor I4 is controlled electrically in accordance with the rotation of a pulley I'IA by a rope or chain II. This rope I'I suspends a counterpoise weight I 1C, and passes over as many idle pulleys IIB as are necessary to guide it. Its other end supports a frustoconical hopper I8 with open large and small ends.

The conveyor 6 delivers material from the bin down a chute at I9 and a suitable sloped channel indicated schematically at 20 to the feeding foot of a chain elevator indicated by 2i which lifts the material en masse in known manner tc a conveyor of the same type as 6, 6A, running as shown by the arrows 22A, 22B; vthis conveyor delivers the material for consumption, but brings back (arrow 22B) any unconsumed material not discharged and this flows down the chute 22C into the hopper I8. The hopper I8 sinks according to the weight of material in it; material escapes from its lower, smaller, end back to the chute 20. 'I'he Dhopper thus, in effect, responds to the demand and causes the whole flow of material to accelerate orlow down in accordance with the demand for material. Simultaneously it opens up or throttles down the cooking steam in pipe I0.

This hopper is normally kept empty, and so the rate of flow down the bin is critically controlled together with the rate of admission of steam and initial wetting (if any) of the material. In Figure 4 an alternative bin arrangement is shown; this comprises straight parallel sides 24, with transverse elements 25 arranged therein. The breadths of these diminish uniformly from the top to the bottom of the bin to accommodate for the increased velocity of flow due to the expansion of the material, and thereby to maintain uniformity of flow and pressure throughout the material. It is believed that by use of bins with diverging walls as shown in Figure l or such as shown in Figure 4, restarting of the apparatus after a period of rest with the apparatus full may be facilitated. The conveyor and other parts shown in the gure correspond to those shown in Figure 1 and are designated by like numerals. Referring Ynow to Figure 5, which shows diagrammatically a speed control employing a photo-electric relay system, the unconsumed material from the discharger is returned as described with reference to Figure 2 down a chute 22C into a frusto-conical hopper 26. The hopper 26, which has open large and small ends, is resiliently mounted by a suitable means as diagrammatically shown by a spring 2l. The hopper carries a vane 28 shown in endwise elevation which is arranged to block the passage of light from sources 29 to light-sensitive cells 3D. The current output from the cells is led to an amplifier or relay 3| of any known or convenient kind and the output current therefrom is used to operate electro-magnetic means at 32 for regulating the speed of a motor 33, which drives through a belt 34 a gear-box 35 and a belt 36, the input conveyor and the discharger. The electro-magnetic means 32 operates to turn a wheel 3l `which turns a. steam-regulating cock 38 in the steam pipe 39. It will be appreciated that the rate of flow of material from .the hopper will depend on the head of and therefore on the weight of material in the hopper, and when the hopper yields on its suport it successively blocks the passage of light from the sources to cells, thereby reducing the current to the amplifier. It is arranged that with the reduced output from the amplifier the speed of the motor is reduced. The apparatus described is designed for the cooking of whole maize by steam; it may be varied for different treatments and materials. In all cases, however, the bin will be kept full and the internal arrangements thereof will consist of as many transverse elements as will, considering their nature and spacing, cause the material to descend uniformly without substantial pressure and to be submitted uniformly to the treatment admitted.

What I claim is:

1. Apparatus for the cooking of cereal in granular or like form by steam, comprising a bin, inverted channel section transverse elements therein, perforated pipes housed in and -below said elements, a source of steam preferably connected to' said pipes, means for controllably supplying material to the top of said bin, means for controllably, evenly and continuously withdrawing material over the whole transverse area of the bottom of said bin, means for conveying away material so withdrawn and for delivering the same, means for returningundelivered material, means for measuring such undelivered material, means operated by said measuring means for controlling the rate of supply to said bin, the' rate of discharge from said bin, the operational rate of said conveyor and the admission of steam, substantially as described. q

2. Apparatus for treating material, comprising, a material treating device, means for passing material through said device for treatment therein including means-for discharging said material from said device, delivery means for carrying discharged material away from said discharging means and delivering at least a portion of the same from said apparatus, means for returning undelivered material to said delivery means, measuring means for measuring said undelivered material, and means `operated by said measuring.

means for controlling the amount of material passed through said treating device.

3. Apparatus for treating material, comprising, a lmaterialy treating Ichamber through which said material is passed, charging means for introduc-V ing material into said chamber, discharging means for discharging material from said chamber, delivery means for carrying material away from said discharging means and delivering at least a portion of the same from said apparatus,

means for returning undelivered material to said delivery means, means for measuring the material returned to said delivery means, and means operated by said measuring means for controlling f said charging and discharging means to control the rate of charging material to said chamber and 'the rate of discharging material from said chamber.

4. Apparatus comprising a bin, transverse elements therein so spaced and numbered as to result in a substantially equal distribution of pressure of downwardly moving material in said bin, and a discharger at the bottom ofthe bin capable of withdrawing the material from within the bin evenly and continuously over substantially the whole transverse area of the bottom of said bin, means for controllably vsupplying the material to the top of the bin, means for controlling the rate of operation of the discharging' means, and means responsive to the rate of ilow o! material at a predetermined point, whichl responsive means controls said supplying and discharging means.

5. Apparatus comprising a bin, transverse elements therein so'spacedand numbered as to result in a substantially equal distribution of pressure of downwardly moving material in said bin, and a discharger at the bottom of the bin capable of withdrawing the material from within the bin evenly and continuouslyover substantially the whole transverse area of the bottom of said bin, and means for controllably supplying material to the top of thebin, means for controlling the operative rate of` said discharger, apparatus for returning unconsumed material towards the bin, means for measuring said returned material and means whereby said measuring means controls the supply and discharge of material to and from the bin.

6. Apparatus comprising a bin, transverse elements therein so spaced and numbered as. to result in a substantially equal distribution of pressure of downwardly moving material invsaid bin, and a discharger at the bottom of the bin capable of withdrawing the material from within the bin evenly and continuously over substantially vthe whole transverse area of the bottom of said bin, and means for controllably supplying material to the top of the bin, means for controlling the operational rate of said discharging means, and a weighing device adapted to be deflected by the passage of material therethrough to control said supplying andv discharging means.

7. Apparatus comprising a bin, transverse elementstherein so spaced and numbered as to result in a substantially equal distribution of pressure of downwardly moving material in said bin, and a discharger at the bottom of the bin capable of withdrawing the material from Within the bin evenly and continuously over substan` tially the whole transverse area of the bottom of said bin, and means for controllably supplying material to the top of the bin, means for controlling the operational rate of said discharging means, and photoelectric controlling means whereby said supplying and discharging means are controlled as to their operational rate.

8. Apparatus comprising a bin, transverse elements therein so spaced and numbered as to result in a substantially equal distribution of pressure of downwardly moving material in said bin, and a discharger at the bottom of the bin capable of withdrawing the material from within the bin evenly and continuously over substantially the whole transverse area of the bottom of said bin, said transverse elements being arralglnto diminish in breadth progressively down sa HERBERT BARNSDALE.

Images