US2296516A - Briquette press - Google Patents

Description

Sept. 22, 1942. w. c. Goss BBIQUETTE "PRESS Filed Feb. 24, 1939 5 sheets-sheet 1 ,////f am G 56V/ R w Nv |||11\ y m 8.x- M. m Ill uw mw wN mm, .mg KWN. WT n uw MPV/A 1W vw w m mm wv w I Vl i 9 a f NQ MN. A@ wv MQ MN NN .m

Q xv v www ATTORNEY Sept. 22, 1942. w, c, AGoss l 2,296,516

BRIQUETTE PRESS Filed Feb. 24, 1939 l 3 Sheets-Sheet 2 Y* f UI I w s VQH w v w1 Kor lb .NN v

l Fb Q Q@ s Q Us s g N o INVENTOR Waff/1676 03s /w Bgm/W5 7' ATTORNEY Sept. 22, 1942. w- C. GOSS BRIQUETTE PRESS Filed Feb. 24, 195e I5 Sheets-Sheet 5 mnlluHmIV/Wm 1 1 i f I Il INVENTOR WPTH C 6053 ATTORNEY Patented Sept. 22, 1942 Worth C. Goss, Seattle, Wash., assigner to William A. Carlisle, Sr., Seattle, Wash.

Application February 24, 1939, Serial No. 258,293

4 Claims.

This invention relates to improvements 'in presses, land has reference more particularly to ipresses for the formation of briquettes from finely divided, or comminuted cellulose material, particularly material that is formed from straw, dried corn stalks, hay, alfalfa, etc.; the present machine -being designed particularly for the briquetting of material derived from straw and 1937, under Serial No. 180,376, I have disclosed an impact press and the use of a high vacuum for withdrawal of air from the material to be cornstalks, but which may be made suitable for 'criquetting materials -deri-ved from any of the above mentioned, as .well as other materials, including that derived f rom wood waste.

To impart a better understanding of the present invention and its advantages over machines heretofore used, it wllhere be explained that in the briquetting of any nely divided material, such as is herein contemplated, there is the vital problem of expelling` the air therefrom, especially that air which is contained in the particles or in the interstices between the particles of material when received in the mold for compression. The necessity for the dispelling of air in the briquetting operation is by reason of the fact that any air that is trapped, or retained in the material, operates to give the finished product a certain degree of sponginess or looseness. Furthermore, by reason'of the tendency of expansion of air entrapped under compression, it is not possible, when briquetting pressure is removed, to obtain the desired solidity or unity, or to accomplish that desired permanent binding together of the particles of material that ,will insure the briquette against deterioration in storage, nor will it be possible to obtain the desired results from the standpointof the briquette being a long burning and eiiicient fuel.

Solidity and `unityV o f the briquetted product is the vital'and essential factor in themanufacture ofl such fuel, and it has always been a problem in this industry vjust how to most eectively and satisfactorily unify the comminuted material. Prior art alongthis line will disclose many different treatments o f the material: the application of heat; vthe use ofv binders of various kinds; the addition offxnoisture to insure unity, but'for those materials `above contemplated, in the manufacturing of briquettes, it is now quite well established'that lno moisture, or adhesive binder need bemixed with the material to obtain the desired 'results 'provided thatall air can be expelled from the material and sufficient pressure applied linthe briquetting operation to unite the particles ofcom'minuted material in'a single',

solid piece.-L f l In mycopendingapplication-filmen Dec. 13,

as expelled from the material delivered under .briquetted as it is advanced to the briquette molds. The mechanism shown in that application provides means for eiecting an initial compression of the material, -for displacement of air ,from between the particles, and it utilizes the high vacuum for extracting that air which isnot expelled from the material by this initial compression which takes place in a slotted :feed tube. While this means and method shown is entirely satisfactory from the standpoint of -air extraction, it does, however,necessitate a very heavy machine, and one not adapted for use as a portable unit. Therefore, it has been the principal object of this invention to provide a briquetting press of a portable character, capable of forming briquettes under extreme pressure, into solid unity andfree of air and not requiring use of high vacuum chambers or extreme vacuum producing devices in obtaining these' results. As

vacuum pumps are available which produce a vacuum of moderate proportions; for example, up to and including twenty-fourinches 0f mercury, which are quite inexpensive and light, it is considered practicable for one modification of the machine under discussion at the present time, to incorporate the use of one of these low vacuum :pumps as a means of reducing the air included in the comminuted material to be brlquetted and the remaining air being excluded by means hereinafter described. f

It is` also an object of this invention to provide an improved type of press, wherein a reciprocating ram advances definitechargesof material into a, compression tube and there forms them into briquettes; and wherein said compression tube comprises a plurality o f longitudinally extending, segmental bars, slightly spaced to provide narrow 'slits between them for escape of air,

pressure of the ram.

A further object of the invention is to provide a novel forming tubel with which there is associated a'novel form of clamp device that operates' automatically, under control of the briquette forming ram for holding the tube yat one diameter while the material is being compressed therein into a briquette, and then to allow va slight expansionof 'the tube',A thus to somewhat relieve the frictional pressure between the briquette 'and tube wall, thus to permit, without requiring excessive power finput, advancement of the c olumn of briquettes in the tube toward its discharge end.

Further objects of the invention reside in the details of construction' of the vcompression tube and clamp and devices for synchronizing the action of the clamp with travel of the hforming Still further objects ofthe invention reside in the details of construction. of various parts of the machine. their combination and mode of operation as .will hereinafter be fully described.

' In accomplishing'y these and other objects of the invention, I have provided the improved details of construction, the preferred forms of which are illustrated in the accompanying drawings, wherein-- Fig. 1 is a longitudinal section, in a vertical` plane, of a briquette press embodying the present invention.

- Fig. 2 is an enlarged cross section on the line 2-2 in Fig. 1, showing the slotted feed tube.

Fig. 3 is a cross section of the `forming tube and clamp on line 3 3 in Fig. 1.

Fig. 4 is a. plan view of the machine.

.Fig 5 is a vertical cross section on line 5--5 in Fig. 1.

-of the closer packing of the material.

tional air will be displaced therefrom, and that the further the material is advanced downwardly in the tube, the greater will be its compression and the more will be the percentage of Fig. 6 is a vertical cross section of the machine on the line 6-6 inFig. '1, particularlyy illustrating the hopper and feed mechanism.

Fig. 7 is an enlarged sectional detail of the clamp control valve mechanism and the clamp. Fig. 8 is a cross sectional detail indicating the travel of the 4forming ram withreference to the air displaced therefrom.

-In order that the maximum amount of air may be displaced from the material in this action of feeding it into the tube 4, the tube 3 is formed with a plurality of air escape slits I0 lengthwise thereof, relatively close together, and extending from the hopper I to the tube as seen in Figs. 2 and 8.

The slits i0 are quite narrow in order to prevent any material amount of the straw being pressed therethrough and, as seen in Fig. 2, they are somewhat flared toward the outer side of the tube to allow whatever straw that does escape, to fall freely and not clog the slits. Air that is displaced by reason of pressure on the straw or material in the tube 3, finds its escape through l these slots as the charges are advanced downformation of the briquette and release of the clamp.

Fig. 9 is a cross sectional view of the compression zone ofthe briquette forming tube, particularly illustrating a steam jacket applied thereto.

Referring more in detail to thedrawings- In Fig. 1, I have shown, in a diagrammatic manner, a preferred form of machine embodyingthe present invention, and 'especially adapted for the briquetting of straw, or the like; it being v understood that the materialy to be briequetted, lprior to its being brought to this machine, is

reduced to a comminuted condition by any suitable means. y

The present machine comprises a hopper I into which the comminuted material of a selected kind, which may be referred to as straw, is delivered from a supply tube 2. mounted upon the upper end of a vertical delivv ery tube l3, which, at. its lowerfend, opens into a horizontal forming or pressure tube 4, later described in detail.

The vertical tube 3 is rectangular in cross section, as noted by the cross sectional view in Fig. 2, and, as seen, is relatively narrow in its cross sectional width as compared to its cross section length in the direction of the tube 4.

VMounted above the hopper I and coaxially, alined. with the tube 3, is a vertically reciprocal feed ram operable to press charges of straw from the hopper I into Ithe upper end of delivery tube 3. This ram comprises a rod 6 mounted for reciprocation in a xed guide bearings 'I-I.

At its lower end, the rod 6 mounts a rshoe or pad 6a which serves, when rod 6 is downwardly actuated, to press charges of straw downwardly into the delivery tube 3; these charges being adl -vanced progressively to the forming tube 4.

The rod 6 is operatively connected at its upper end, as will later be described, with a driven crank shaft 3 and operates in timing with move- The hopper is Wardly, the effect being that on entering the tube the charges of material are so tightly compressed as to be substantially free of air.

IIvhe briquette forming tube i is relatively long and is horizontally disposed. At one end it is supported by a housing II, and at its other end by a clamp I2, later described in detail. At the left-hand end, as seen in Fig. 1, the tubet reciprocally contains a briquette forming piston or ram I3, the inner end portion of which reciprocates through' the distance spannedby the bracket designated in Fig. 8 by character T; its opposite limits of travel being designated more particularly bythe lines aand b respectively. The tube 4 receives the material directly from the tube 3, and it will be noted by reference to Fig. 6, that the diameterof the tube 4 at the point of connection with tube 3, corresponds to the width of tube 3, so as to receive the column of material advanced downwardly in tube 3 without any resistance.

The ram or piston I3 hasa hat inner end surface I3' lying in a plane at right angles to its axis. At its outer end, the ram has operative connection, through thev mediacy of a link I4, with a crank arm I5 fixed on a rotatably driven cross shaft I6, mounted in a housing IIa. Shaft I6 is driven by a gear II, which. in turn, is driven by a relatively small gear I8 on a driven shaft I9. Shaft I9 preferably would be equipped witha fly wheel 20 to insure steady operation, and for other reasons which are obvious.

That part of tube 4 at the right of the feed tube 3, as seen in Fig. 1, is formed by a plurality of separate, longitudinally extending segmental bars 4a, 4b, 4c and 4d, shown in Fig. 3, which are arranged to form a tubular mold and a guideway are bound together by means of a pair of spaced,- encircling collars 22-22, which hold the tube against diametrical expansion at that point. At the delivery end of the tube, the segmental bars of simple ypressure through thev slotted tubes.A F.fand then briduettedfafter having been cooled It will 'b'e understood that `the vacuum seal isV v -formed by a solid section of the feed tube above y the slots and a dsecond vacuum seal being formed in the main compression tube by a solid section of the main compression-tube which is inside f the first conning ring. In each case, the packed v,material acts to prevent thej ingress of air into the vacuum housing. t

It has been shown tov be old inthe art of considerably by, lthe introduction of saturated lsteam, has a linear expansion factor of less than exposed to extremely moist'air.-

When the air -in a com'minuted material has vbeen expelled by atmosphereic pressure saturatedI L steam, as above described there isa small mois-v briquette manufacture to Aexclude the air v'from comminuted material by means of a flowof superheated steam therethrough. This process is described in U. S. Patent No. 1,453,988, `issued to Mueller, May 1, 1923; It has been discovered,

' however, that .theMueller method is not satis-` factory for the Aproduction of `abr iquette under the most ideal'conditions. In general, these conditions consist of a comparatively high temperature, as, forexample, 450 F. When superheat- -ture content put into the briquette because of the steam which is absorbed by the comminuted material.- This small moisture content is desirable because of the fact that it tends to balance the moisture content of lthe briquette with the-mois- -vof the material is destroyed by means of high n heat, and what small moisture absorbing propved steam is used to expel the airI from material to `be briquetted at this very high temperature, the steam itself has a very 'great disruptive force, and, in fact, acts in very much the way that air would act upon compression of thebriquette.

' li'his is due to the fact that vaporous water at a temperature of 450 F. exerts a pressure amounting to several hundred pounds per square luch. This, of course, causes an extremedisruptive action as the pressed briquette is released from a briquette machine. 1

A modiilcation of the present invention com# prises iirst heating the material to be brquetted to a very high temperature, such as 450 F., and

then vcooling the material .to a considerable extent by blowing saturated steam at atmospheric pressure through the loose material thereby removing all air, thus substituting an atmosphere of condensible water vapor throughout the comminuted particles. When, this procedure is adopted, it is found that there is no disruptive action due to the presence of the steam because of the fact that the material is cooled enough so that the vapor pressure of the steam is approximately atmospheric. This is due to two factors, the most important of which is comparatively low temperature of the material, and the second of which 'is the hygroscopic absorptive action of the material to be briquetted. This absorptive action tends to reduce the steam pressure quite materially as long as the material is not at an excessive temperature. Thus the air is removed by the saturatedvsteam, but-the steam itself exerts no disruptive force, so that a very briquette will remain solid even when'exposed to moist conditions of the atmosphere. This is not true if the material had originally been.

heated to only 220 F., and' then contacted with superheated steam of the same temperature.

For example, a wood briquette in which the material has been dried at 220 F. and then briquetted by Muellers-superheated steam process, has a linear expansion when exposed to .extremely moist air, of approximately 3% of its linear dimensions. This amountof expansion will cause the material to fall apart and become ture content which the briquette would naturally absorb from the atmosphere upon long stand'- inlg. Thus the main part of the hygroscopicity erty that is left in the material is rendered impotent'` to cause any disintegration in the nished briquette upon long standing in the atmosphere.

With the machine so contructed, it will be understood that the reciprocating ram 6 will keep the tube 3 charged with material, and that the material will be advanced in a compressed condition into tube .4. Since the ram Boperates in unison and in timing with the forming ram I3, it is understood also that the charges will be advanced from tube 3 into tube 4 while the ram I3 is in its retracted position. -These successively advanced charges'are all of the same volume and thus provide for the formation vof briquettes of like size and density.

A feature of this feeding device is that the comminuted material is packed into tube 3 under considerable pressure and by reason of this pressure, the greater percentage of'air is dispelled therefrom, and the charges are advanced in a substantial degree of solidity into tube I for nal compression.

The clamp I2 in this instance is the means that governs the pressure under which the briquettesv are formed for it is to be understood that with the column of formedv briquettes held in tube 4 against advancement, the compression of material under action of the ram I3 will continue until the clamp releases the tube for slight expansion, whereupon the compression ceases and the entire column of briquettes is advanced by the pressure applied against the last finished briquette. In the present instance, the briquetes holding pressure for advancement of the column relieves the machine of approximately seveneighths of the power that otherwise would be rea mere heap of comminuted sawdust. On the quired.

The slotting'of -the forming' tube further provides for escape of air lmderthe nal forming action from the material being compressed in the tube. Attention is' also called to the fact that the tube 4 might be rectangular or of other decreasing the tensionV on the springs 08 and Il' shown in Fig, 6. As it is very important from the standpoint of a product which is to be merchandized in packages, that the packages-be of uniform size, this feature in the present machine of an exact control of the size of the individual briquette is very desirable and of considerablecommercial importance.

When the slotted main compression tube -l is used with the application of steam at atmospheric pressure, it is fdesirable that a steamy jacket Ill surround the back portion of. this tube along that part within the compression zone a--b in Fig. 9, and that this jacket be filled with atmospheric pressure steam so that with each backward stroke'of the ram I3. steam will be drawn into the compression tube' instead of air. This will have the effect of eliminating any substantial quantities of air which would otherwise Having thus described my invention, what I claim as new therein and desire to secureby Letters Patent is:

1. A briquette press comprising "a forming tube, a feed tube opening into the forming tube.

means operable to charge the feed tube with a column of comxnlnutedmaterial to be briquetted `under air eliminating compression and to advance the charge while compressed progressively into the forming tube. and means operable ini termittently to further compress the material as received by the forming tube from the feed tube into briquettes; saidfeed tube being provided along its length with openings for escape `of! air as eliminatedv from material incident to its compression in the feed tube.

2. A briquette press comprising a forming tube, a feed tube opening into the forming tube, means operable to lcharge the feed tube with a continuous column of material to be briquetted under air eliminating compressionlandto advance the column progressivelyinto the forming tube, and means operablelntermittentlyto further compress that part of the column of material received by the forming tube from `the feed tube into individual briquettes; said feed tube being provided along its length with openings for escape of air as eliminated from material incident to compression of the material in the feed tube. and said forming tube being provided with .openings for escapexnenta of air dispelled from the material incident to formation of the briquettes.

3. A briquette press comprising a forming tube. I a feed tube opening into the forming tube, means operable to charge the feed tube with a column of comminuted material, means for the introduction of saturated steam to the material prior to compression to expel the air therefrom prior to entering the feed tube, means to advance the column of compressed material progressively from the feed tube into the forming tube, andI means operable tov further compress the material in the forming tube into briquettes'.

4. In a briquette press. a forming tube adapted to receive charges of material to be formed into briquettes, a ram reciprocally operable in the tube through a stroke of definite length for forming the briquettes and for the. advancement of the formed briquettes as a continuous column along the tube; said tube beinglongitudinally divided into sections to provide for a limited diametrio expansion and contraction of the tube, a hydraulic clamp housing enclosing the divided part of the tube and having a flexible inside wall contacting with the tube and means operable in timing with the reciprocal actions of the, ram for delivery of a hydraulic pressure medium into the housing to cause contraction of the'tube and for relieving the pressure in the housing to permit expansion of the tube.

WORTH C. GOSS.

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