GB2148779A - Briquette making machine - Google Patents

Abstract

The briquette making machine comprises a waste-receiving bin (11), one wall of which is defined by a plate (12) to sweep waste towards a guillotine (15) forming another wall of the bin (11). The guillotine (15) comprises a blade portion (19) to shear any waste straddling the bin and a compression chamber defined by the blade portion (19) and a wall (17). With the guillotine (15) in its most downward position a piston (23) configured to conform to the cross-sectional shape of the compression chamber clears the compressed waste therefrom by further compressing it against and eventually through a constricted discharge opening. The opening is defined by wheels (25, 26) which longitudinally groove the emergent briquette. <IMAGE>

Description

SPECIFICATION Briquette making machine Field of the invention The invention relates to machines for making compressed fuel briquettes from waste cardboard and similar material.

Review of the prior art Methods of making briquettes from waste cardboard and other material, by extruding material through a constriction aperture, are known from inter alia the following patents which constitute the most relevant prior art currently known to the applicant: Swedish 105 654; 395 432 German 2 359 450; 912 167; 1 752 111; 1139 743; 1 806 209; 1 402 382; 1 239 930.

Summary of the invention In a briquette-making machine embodying the present invention, a power-driven plate sweeps the waste from the bin towards and at least partly into the initially open breach of a compression chamber; a power-driven waste-shearing guillotine progressively closes off the breach and compresses the material within the compression chamber; a power-driven piston moves at an angle, preferably a right-angle, to the guillotine to clear the compressed waste from the compression chamber and compress it against and eventually through a constricted discharge orifice; and the discharge orifice is so configured as to groove the emergent briquette longitudinally.

By so grooving the briquette the compressed layered material of the briquette is held together longer and does not too readily break apart into flakes as it comes off the machine. Both these features are of decisive importance for quiet combustion during its subsequent use as a fuel.

The groove or grooves may be imparted to the briquette surface by ridged wheels, which may themselves define the orifice and which will promote a smoother discharge of compressed material from the orifice.

At least one of these wheels may be withdrawable, preferably by power-operated means, if the orifice clogs. Such a withdrawable wheel may for example be held against the briquette surface, and automatically allowed to withdraw therefrom if necessary, by a fluid-filled ram in circuit with a fluid accumulator.

One or more of the wheels just referred to may exhibit a ridge which is generally triangular in cross-section and whose apex is radiused. This counteracts the natural tendency of the emergent briquette to curl up and back on itself as it comes off the grooving means.

Advantageously the grooving wheel may be a composite wheel whose ridge is of harder material than the main body of the wheel. The expense of the harder material is thereby minimised without detracting from the efficacy of the wheel.

Advantageously the groove may be imparted to the top surface of the emergent briquette and an elongate spring bar may press into and along that groove, to resist the tendency of the briquette to curl up and back on itself once discharged.

A lip may advantageously be provided, on the side of the guillotine facing the sweep plate, to positively push the waste further into the bin as the guillotine moves to close off the breach of the compression chamber.

Advantageously the bin is parallel-sided and open-topped, for more efficient delivery of the incoming waste to the compression chamber.

The guillotine and sweep plate may be combined in one power-driven plate, or alternatively they may be constituted by separately driven plates.

Brief description of the drawings The machine and modification thereof shown in the accompanying drawings, are currently the best ways known to the applicant of putting the invention into practice. In these drawings: Figure I shows the machine in diagramatic side elevation: Figure 2 shows parts of the machine of Figure 1 in plan: Figure 3 is a detailed view of the discharge end of the machine: Figure 4 shows the discharge end when viewed from the side: Figure 5 shows a modified discharge orifice: and Figure 6 shows the orifice of Figure 5 when viewed from the side.

A waste receiving bin 11 is parallel-sided and open-topped. A sweep plate 12 forms one side wall of the bin, and is pivoted to the bin about a top hinge 13. Fluid filled rams 14, only one of which is shown in the drawings, move the sweep plate 12 about its hinges 13 towards and away from a guillotine which is referenced generally 15 and one of whose faces forms, in use, a side wall of the bin 11 opposite to that formed by the plate 12.

An arcuate base plate 16 defines the bottom of the bin 11. The plate 12 sweeps to and fro along the arcuate base plate 16 as the rams 14 respectively retract and extend.

A plate 17 is fixed to the main framework of the machine, behind the guillotine 15, and forms one wall of a compression chamber. The guillotine 15, as it descends, closes off the breach 18 of the compression chamber and defines the other wall of that chamber. The bottom portion 19 of the guillotine 15 is configured as a blade which will shear the cardboard or other waste material swept at least partly into the breach 18 by the plate 12 in use.

The guillotine 15 is driven by a rack and pinion drive indicated generally at 9. The drive is powered by a motor and gearbox unit which can be of proprietary kind and readily be selected by the intended skilled addressee of this specification. It is neither described nor illustrated here.

A lip 21, on the side of the guillotine 15 which faces the sweep plate 12, acts to push the waste down into the bin as the guillotine descends.

The end of the arcuate plate 16 against which the guillotine blade 19 closes off the compression chamber breach 18, defines a tangent of approximately 45" with a notional horizontal line.

The top 17a of the plate wall 17 is bent backwards at an angle to the main body of the plate, as Figure 1 shows. A chute 22 is fixed to the main frame of the machine below this bent out portion 17a. Any cardboard or other waste material escaping up the side of the plate 17 and being discharged over the end of the bent out portion 17a will fall on to the chute 22. The chute slopes down towards an access door (not illustrated) which can periodically be opened to empty any material caught by the chute 22.

A power-driven piston 23 in the form of an elongate solid square section bar is toothed on its underside. A pinion 24 drives the toothed bar 23 into and out of the compression chamber defined by the plate wall 17 and guillotine blade 19. The bar 23 moves under its rack and pinion drive at rightangles to the movement of the guillotine 15. In this particular machine, the guillotine 15 moves vertically up-and-down whilst the power-driven bar 23 moves horizontally back and forth.

The bar 23 is driven by a motor and gear box unit similar to that used to drive the guillotine rack and pinion drive 9.

The unit can again be selected from known alternatives, and is neither described or illustrated herein.

In use, cardboard waste is dropped into the open-topped parallel-sided bin 11, and is swept by the plate 12 towards and at least partly into the breach 18 of the compression chamber. initially the guillotine 15 is in its raised position to open the breach. The guillotine then descends, shearing through any cardboard waste which straddles the breach, and closing off the breach whilst simultaneously and progressively compressing the cardboard waste in the chamber defined between the guillotine blade 19 and the plate wall 17.

Throughout this operation, the bar 23 is in its retracted position illustrated in Figure 2.

With the guillotine driven fully down, and held there, the bar 23 is then driven forward into the compression chamber to compress the already compressed waste in a direction at right-angles to that in which the guillotine compressed it. The bar 23 continues to drive forward and effectively clears the twice-compressed waste from the compression chamber to compress it against and eventually through a constricted discharge orifice.

As Figures 3 and 4 show, the orifice is defined by respective top and bottom wheels 25, 26. Each of these wheels is freely rotatable about its own respective axis which runs horizontally.

The bottom wheel 25 is fixed in the discharge channel 27a of the machine which leads out of and forms an extension of the base and the side walls of the compression chamber. The top wheel 26 is carried by a fluid-filled ram 27 which is in circuit with a fluid accumulator (not shown).

Both wheels 25, 26 exhibit ridges which are triangular when viewed end-on, ie. as in Figure 3.

The ridged portion of the top wheel 26 is made of harder material than the rest of the wheel.

In both wheels, the apex of the triangular section ridged portion is radiused.

As Figure 4 shows, the ram 27 is pivoted between the main frame of the machine and one end of a fork 28 which supports the wheel 26 and which is pivoted at its other end (29) to the main frame of the machine. The ram 27 swings the fork 28, and hence the wheel 26, about the pivot 29 in response to an automatically sensed pressure of material between the wheels 25, 26. If the discharge orifice is about to clog, the ram 27 will automatically withdraw the wheel 26 and will repeat that operation several times if necessary to allow the blockage to clear itself.

If the discharge orifice remains clogged, even after several withdrawals and repositionings of the wheel 26, the whole machine simply switches off; the ram 27 withdraws the wheel 26 completely; and the discharge orifice has to be cleared manually before the machine can be re-set and restarted.

As the compressed and continuous briquette strand comes through the discharge orifice, the wheels 25, 26 impart grooves to each of its top and bottom surfaces. These grooves help to lock the compressed material together. The imparting of these grooves gives to the material an inherent tendency to curl up and back on itself as it emerges from the orifice. A discharge channel 31 is fixed upwardly to rise from the discharge orifice, to accommodate this tendency to a certain extent.

A torsion spring 32 is fixed to the top of the discharge channel 31, and has an elongate spring bar extension 33 which is relatively heavily springloaded towards the base of the channel 31. In use, the spring bar 33 presses into and along the groove in the top surface of the emergent briquette, and keeps it in the channel.

As the briquette emerges finally from the end of the discharge channel 33, its own projecting weight tends to break it off into individual briquettes of relatively short length.

Various practical features are incorporated into the machine described and illustrated, to ensure its automatic and safe operation. For example, limit switches allow the bar 23 to withdraw completely from the compression chamber (ie. as illustrated in Figure 2) but prevent it from being driven so far back that it comes out of its bearing. Sensors may restrict the sweep of the plate 12 if the rams 14 encounter too much resistance from material in the bin 11. These and other practical details can be settled without inventive thought by the skilled reader.

The machine illustrated is of course only one example, although currently the preferred example, of putting the invention into practice. It could be modified within the scope of the invention. For instance, the rack and pinion drives to the guillotine 15 and power-driven piston bar 23 could both be replaced by fluid driven rams.

Briquettes produced by a machine embodying the invention are clearly so linked to the machine as to form part of the same inventive concept. To that end the invention includes, within its scope, a briquette made from cardboard or other waste material by compressing the material in two directions at an angle, preferably a right-angle, to one another, and then compressing the material again through a constricted discharge orifice which imparts a surface groove to the emergent briquette.

In Figures 5 and 6, parts which correspond to those shown in Figures 1 to 4 are given the same respective reference numerals. There is a ridged wheel 25 rotating freely at the bottom of the discharge orifice. There is similarly a ridged top wheel 26 carried in freely rotatable manner on a plate 34.

In this particular embodiment there are also respective opposite side wheels 35, 36 which are ridged and are of equal diameter to the other two wheels.

All four wheels are fixed to their respective mounting surfaces by removable screws 37. The wheels 25, 35, 36 are not adjustable, once fixed in position, with respect to one another. The plate 34 which carries the wheel 26 is, by contrast, free to move vertically up and down within a yoke 38 which is of inverted U form and which is fixed at each of its opposite ends by screws 39 to the main frame of the machine.

A headed screw 41 passes through the centre of the top of the yoke 38 and engages a tube 42. The tube 42 enshrouds a compression spring 43 coiled about the shank of the screw 41. The spring 43 is compressed between the top of the tube 42 and the top surface of the plate 34.

The coiled compression spring 43 cushions the grooving action of the top wheel 26 against the briquette strand. If a harder, more compressive, grooving impact is needed, the screw 41 is turned one way to move the plate 34 and wheel 26 towards the bottom wheel 25. If a less hard grooving impact is to be imparted, the screw 41 is turned the other way to increase the distance between the wheels 25 and 26. In either event the screw 41 can be locked in its final desired position.

The discharge orifice defined by the mechanism of Figures 5 and 6 imparts one groove simultaneously to each of the four sides of the emergent square-section briquette. This has the advantage that there is less tendency for the briquette to curl up and back on itself as it leaves the grooving wheels.

Claims (13)

1. A machine to make briquettes from waste comprising a waste-receiving bin, a plate to sweep waste from the bin towards and at least partly into the initially open breach of a compression chamber, power-driven guillotine means progressively to close off the breach, to shear waste straddling the breach and to compress the waste within the compression chamber, and a power-driven piston movable transversely to the guillotine means to clear the compressed waste from the compression chamber and further compress it against and eventually through a constricted discharge orifice which is so configured as to groove longitudinally the emergent briquette.

2. A machine as claimed in claim 1, wherein the discharge orifice is at least partially defined by one or more wheels adapted to impart respectively one or more grooves.

3. A machine as claimed in claim 2, wherein one or more of the wheels is ridged.

4. A machine as claimed in claim 3, wherein the or each of the one or more of the ridged wheels has a ridge which is generally triangular in crosssection and of which the apex is radiused.

5. A machine as claimed in either claim 3 or claim 4 wherein the or each of the one or more ridged wheels is of composite construction and the ridge of the wheel is of harder material than the main body of the wheel.

6. A machine as claimed in any one of claims 2 to 5, wherein at least one of the wheels may be withdrawn if the discharge orifice clogs.

7. A machine as claimed in Claim 6, wherein power operated means are provided to withdraw the at least one withdrawable wheel.

8. A machine as claimed in claim 7, wherein the at least one withdrawable wheel is held against the briquette surface, and withdrawn therefrom if necessary, by a fluid-filled ram in circuit with a fluid accumulator.

9. A machine as claimed in any of the preceding claims, wherein an elongate spring bar is arranged to press into and along at least one of the longitudinal grooves.

10. A machine as claimed in any one of the preceding claims, further comprising a lip, on the side of the guillotine means facing the plate, which acts to push waste further into the bin as the guillotine means moves to close off the breach of the compression chamber.

11. A machine to make briquettes from waste substantially as described herein with reference to the accompanying drawings.

12. A method of making a briquette comprising the steps of compressing cardboard or other cellulosic waste, further comprising the waste in a direction transverse to the direction of first compression, and longitudinally grooving the briquette emergent from the further compression step.

13. A briquette when made by a machine as claimed in any one of claims 1 to 11 or according to the method claimed in claim 12.