CA1288719C - Conveyor apparatus - Google Patents

Abstract

ABSTRACT
An apparatus (1) for conveying and compacting material in which the material includes fractions of different sizes, densities, elasticity, moisture-content etc. The apparatus has at least one shaftless spiral (3), in which each spiral is disposed in a pre-ferably enclosed casing (2) of, for example, U-shaped and/or circular cross section. A drive means (4) is provided for rotation of the spiral and is placed in conjunction with that part of the casing where the material is fed into the casing. In the opposite end of the casing, i.e. at the end which is located adjacent the discharge section (18) of the casing, the casing surrounds the spiral with slight play, and, moreover, the casing has, in an extension of the spiral, an end region (23) where the spiral is not surrounded by the casing. As a rule, there are also provided counterpressure members which brake the movement of the material. In certain embodiments, the contemplated braking effect is realized in that the end region (23) offers sufficient friction in relation to the material.

Description

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TITLE ()F THE I~lVEi~TION: A C(~NVEY()R APPAf~ATU~

FIELD OF THE INVENTION
The present invention relates to an apparatus For receiving conveying and/or impacting of material in ~Ihich are included fractions of different s;zes, densit;es~ elasticity, moisture-content etc,, the apparatus ;ncluding at least one shaftless spiral in ~Ihich each spiral is disposed in a preferably closed casing and, the sp;ral or spirals, respectively, in conjunction ~Jith that portion oF the casing where the material is received, ancl there are provided, at least for one of the combinations of casing - spiral, counterpressure members which arrest or brake the movement of the material in con-junction ~Jith that portion of the casing ~Jhich serves as a discharge portion for the material.

~ACKGROU~D
Material of the type mentioned by way of introduction needs to be moved in many different contexts, both in industrial operations and in, for example, municipal refuse disposal and management (refuse handling, screenin~s from the ~lastewater treatment plants and so on).
Consequently, such material is handled in large quantities daily and it is a reality that this handling cannot be effected without meeting a number of problems. These are because the material is, as a rule, difficult to handle, for example in that it is bulky and need to be compacted in order to attain an acceptable level of transport economy. When the material is ~/et, it needs to be compacted in order to reduce the moisture-content so as thereby to mal<e for greater ease of handling. For compacting material of the above-indicated type, the pr;or art calls ~or the employment of separate compactors or scre~
presses.
One disadvantage inherent in h-itherto employed combinations of conveyors and compactors is that the combinations require d great deal of space and are costly. In certain applications, hydraulic com-pactors are used, and in other applications, screw presses. The hydraulic compactors take up a great deal of space and operate ~k , . . . .

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intermittently, which occasions problelns in, for example, the formation of material "bridges" at the infeed section, ~Jhile the conventional screw presses find d;fficulty in swallowing the bridge and plug forming materials here under discussion. This is because the screw presses have a centre shaft or axle about which ensnaring material such as textiles~ plastic sheeting, str;ps e-tc. become wound and cause plug formation in the material flow.

SU~RY OF THE INVENTION
The present invention contemplates a conveyor apparatus in which is included means for compaction of the material beiny conveyed and in which the above-indicated disadvantages are obviated to a remark-able extent. The invention relates to a combination of a shaftless spiral and a casing. The combination of spiral and casing creates a compact unit of equiprnent which makes for reliable conveyance of the material and is used, according to the invention, to realise a com-paction of the material at same time as the material is enclosed, which entails that the surrounding environment is not affected. In certain embodiments of the present invention, the employment of compaction reduces the moisture-content in the material, while in other embodiments, the compaction of the material constitutes the basis of a batchwise discharying of the material from the apparatus.
The apparatus includes at least one shaftless spiral which is disposed in a preferably enclosed casing of, For example, U-shaped and/or circular cross-section. A drive means for the rotation of the spiral is disposed in conjunction with that portion of the casing where the material is fed into the combination of casing and spiral, while in the other section of the casing, i.e. in conjunction with the discharge portion of the cas-ing, there is provided a zone in which the casiny is of a cross-section ~Jhich entails that the casing completely surrounds the spiral with slight play. ~ioreover~ the casing is provided with an end region in the extension plane of the ~ .
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sp;ral, in which the spiral is not enclosed by the casing and/or in which a counterpressure member is disposed~
In this zone and/or in conjunction with the end section, compaction of the material takes place. In that portion of the end section where the spiral is not enclosed by the casing, there is a braking or arresting effect on the material which leads to its compaction. In certain embodiments, the compaction is further amplified in that the spiral is provided with progressively diminishing pitcha The spiral is completely free, i.e. is not journalled in that end ~lhich is directed towards the discharge section of the casing.
In one embodiment of the present invention, the counterpressure member consists of a spring-loaded counterpressllre plate wltich is movably journalled in the upper defining surface of the casing and/or in conjunction with the discharge opening of the casing. In certain embodiments, the counterpressure plate is disposed in a receptacle chamber. In other embodiments, the braking effect of the casing on the material is amplified in that the casing, most proximal the discharge opening, is provided with reduced inner cross-section.
In yet a further embodiment, the counterpressure member consists of a receptacle device, for example a container, a hose etc.~ the member being shiftable in the axial direction of the casing. During r~tation of the spiral, the material is conveyed into the receptacle device, the material moving the receptacle device in the axial direc-tion of the splral.
In still a further preferred embodiment of the apparatus~ the counterpressure nlember consists of a shaFtless spiral dispose~l in a casing, this casing having an infeed opening connected to the dis-charge opening of the delivering casing. That casing ~hich discharges the nnaterial is, in this instance, of an orientation which entails that its axis is directed towards the centre axis of the spiral and the receiving combination of casing and spiral. The pitch, speed ~137~3 and/or radial extent of the spiral blades are, in the receiv-ing combination, adapted so as to occasion a brakiny of the material movement before the material reaches the discharge opening of the disclosed casing. Hereby, it is possible in such operation to attain a substantially complete filling of the space in the receiving casing. The substantially complete filling constitutes a precondition for being able to convey the material upwardly in a more or less vertical direction. Thus,according to the present invention, it is possible to dispose the receiving combination with its axis directed, for example, horizontally, vertically, or there-between.
In certain embodiments, the casing is provided with drainage openings which, preferably, are located in that region of the casing where compaction of the material takes place. In such an instance, an orientation of the casing is advantageously selected so as to entail that the discharge section of the casing is placed higher than its infeed section, whereby, on compaction, the pressed out liquid is conveyed in a direction opposite to the direction of movement of the material and is drained out from the casing through the previously-mentioned drainage openings.
According to a still further broad aspect oE the present invention there is provided an apparatus for conveying and compacting material including fractions of different sizes, densities, e].asticity and moisture content. The apparatus comprises a first conveyor including a casing, at least one shaftless spiral disposed in the casing, and supply means for feeding material into the casing. Drive means is also provided for rotating the spiral in the casing such that the spiral advarces the material through the casing. The casing has an outlet towards which the material is advanced by the spiral. The casing includes a first section in which the spiral extends with slight play. The spiral has a terminal ~2887~

4a free end disposed in the first section. The casing includes an end section extending from the first section beyond the terminal free end oE the spiral and is connected to a second means having an inlet means connected to the outlet of the casing. A shaftless spiral is provided in the second means.
The center axis of the shaftless spiral of the second means is located and oriented so that material fed out through the outlet of the casing of the first conveyor is cut off by the shaftless spiral of the second means while the spiral of the second means is rotated.
According to a still further broad aspect of the present invention there is provided a method for conveying and unloading material from an apparatus and wherein the material includes fractions of different sizes, densities, elasticity and moisture content. The method comprises feeding material which is to be advanced into a casing of a first conveyor.
The material is advanced in the casing towards a discharge outlet thereof by rotating a shaftless spiral in the casing.
The spiral terminates, at a free end thereof, at -the end of a precompacting section of the casing in which the spiral extends with slight play. The material is advanced beyond the free end of the spiral through a compaction zone of the casing before being discharged at the outlet. The material which is discharged at the outlet is cut off from the outle-t by rotating a shaftless spiral in a second means and the cu-t ofE material is advanced by the shaftless spiral of the second means towards an outlet of the second means to leave the apparatus at the said outlet.
The nature of the present invention and its aspects will be more readily understood from the following brief descrip-tion of the accompanying drawings, and discussion relating thereto.
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~2~7~3 4b BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings, Fig. 1 is an axial section through an apparatus accord-ing to the present invention;
Figs. la-c are sections taken along the lines A-A, B-B, and C-C in Fig. l;
Fig. 2 shows the material distribution in the longitu-dinal direction of the apparatus;
Figs. 3, 4a, 4b, 4c and 5 illustrate embodiments o~ the apparatus according to the present invention provided with counterpressure members for braking the material on its movement;
Figs. 6a and b are partially sections through embodi-ments of the apparatus according to the present invention, in which the casing of the apparatus is provided with drainage openings;

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Figs. 7a and b are partial sections through ernbodiments o~ the apparatus according to the present invention, in which this is provicled, in conjunction w;th its discharge open;ng with a shiftable receptacle member;
Figs. 8a and b are partial sections through one embodiment of the apparatus accord1ng to the present invention, in wh;ch this, in con-junction with its d;scharge open;ngl cooperates w;th a conveyor apparatus wh;ch includes a casing surrounding a shaftless sp;ral; and Figs, 9a c show detail of the free end of the spiral.

D~TAILED DES~RIPTION OF PREFERRED EMBODIMENTS
Referring to the drawings, Figs. 1 and 2 illustrate the invention in one embodiment which shows the fundamental construction and func-t;on of the invention. In these drawing f;gures, there is shown an apparatus 1 which includes an elongate5 tube-like casing 2 in which ;s placed a shaftless spiral 3. At its one end, the casing is pro-vided with an infeed opening 14 which connects to an upwardly--directed drum 1~. A motor 4 drives the spiral 3 by the intermediary of a gearing and journalling unit 30. The other end of the casing constitutes the discharge portion 18 of the apparatus, which is provided with a discharge opening 24. The spiral is solely journalled in connection with the gearing and journalling unit, wh;le that end of the sp;ral wh;ch is d;rected towards the discharge portion is fully free.
Seen ;n the axial d;rection of the cas;ng, the combinant of sp;ral and cas;ng ;s div;ded into an infeed zone 20, a transport zone 21, a precompaction zone 22 ancl a compaction zone 23. The cross-sec-t;ons through each respective zone ;n the ;llustrated embodiment are apparent From Figs. la-c. It w;ll he appreciatecl from these F;gures that the cross-section of the casing in the precompaction zone is substantially circular and surrounds the spiral with slight play.
Fig. 1 also shows by solid l;ne a relatively abrupt transition between the transport zone 21 and the precompaction zone 22. However, ;n certain physical appl;cat;ons, the embodiment shown by broken lines is selected, with a relatively continuous transition between the cross-sections of the transport zone and the precompaction zone.

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Fig, 2 shows in particular how the material flow ~0 encompasses a relatively small portion of the cross-sectlon of the casing as long as the material is in the transport zone 21, and how the material, on its passage through the precompaction zone, takes up a stead;ly increasing part of the cross-section in order, in the compaction zone proper, substantially to fill out the entire cross-section.
Figs. 3 ancl 4a, 4b and 4c show how the combination of spiral and casing is provided with a counterpressure member 25, 8, for arresting or braking the movement of the material in th compaction zone 23 of the casing. In the embodiment illustrated in Fig. 3, the counter-pressure member 25 is formed in that the movement of the rnaterial is braked during movement in the longitudinal direction of the casing, because of friction against the inner surface of the casing. In certain physic~l applications, the braking effect is amplified in that the casing is, in the region of the compaction zone 23, provided with reduced inner cross-section.
Fig. 4a shows, first, one embodiment in ~hich the counterpressure member consists of a counterpressure plate 8a disposed in association with the discharge opening 24 and pivotally journalled in conjunction with the upper region of the d;scharge opening, and moYable in the direction of the double-headed arrow A; and secondly, an embodiment in which the counterpressure member consists of a counterpressure plate 8b which is pivotal and preferably return spriny~biased in the upper defining surface 27 of the casing 2. Fig. 4b shows a partial longitudinal section and Fig. 4c a view taken along the line D-U in Fig. 4b of one ernhodiment in which the counterpressure member consists of a split cone 34. For example, the cone comprises two halves 34a and 34b and is openable under the counteraction oF springs 35 whose spring force is adapted to provide that counterpressure which is requsite to attain the intended compaction of the material.
Fig. 5 shows one embodiment in which the counterpressure plate ~a, in conjunction with the discharge opening 24, is disposed in a receptacle chamber 7. In the embodiment illustrated in this Figure, the counterpressure plate is journalled in the upper defining surface of the chamber, but the journalling may, for example, correspond to that of those embodiments as shown in Fig. 41 . , .

37~L9 Figs. 6a and b show embodiments in which the casing 2, in conjunction with the precompaction zone 22 and the compaction zone 23, is provided with drainage openings 33.
Figs. 7a and b show embodiments of the present invention in which the counterpressure member consists of a receptacle device 26,28, shiftable in the axial direction of the casing and, in Fig. 7a, comprising a container 26, ~Ihile in Fig. 7b, a hose 28. In this instance, the hose 2~ is drawn out from a magazine 29. In certain embodiments, braking means 36 are provided for restricting the withdrawal of the hose from the magazine. In the Figures, an arrow F
intimates a Force which is counter-directed to the movement of the container, The arrow represents a device, for example a hydraulic cylinder. In Fig. 7a, it is shown that, in certain embodiments, the hose 28 cooperates with the container 26 (broken lines) and is brought into abutment with the inner surfaces of the container according as the hose is filled with material from the casing. Thus, Figs. 7a and b show embodiments of the invention in which the mate-rial surrounded by the container and/or the hose is compacted.
Figs. 8a and b show one embodiment of the invention in which the apparatus 1 includes at least one supplementary conveyor apparatus 50 comprising a casing 52 and a shaftless spiral 53 placed therein. The spiral is driven by a motor 54 by the intermediary of a gearing and journalling unit 51 and its speed is, thus, for example by modifica-tion of the gear ratio, adjustable to any desired level. The direc-tion of the first spiral 3 and/or a central shaft of the discharge end 1~ of the casing is towards the central axis of the spiral 53 of the conveyor apparatus. The openiny surface area of the discharge opening 24 of the casing 2 substantially agrees with the cross-sectional area of the receiving casing 52, both of the casings being substantially sealingly interconnected. The conveyor apparatus 50, is, in certain embodiments, disposed to move the material essentially hori~ontally, while in other embodiments, movement is effected during alteration of the level of the material. There are also embodiments of the present invention in which the casing 52 of the conveyor apparatus 50 with the spiral placed therein, has a substantially vertical direction. In this instance~ the free end of the spiral is directed upwardly.

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Figs. 9a c show embodiments of the free end 31-32 of the spiral 3. In Fig, 9a, the end 31 of the spiral terminates in such a manner that its blade height continuously diminishes from the inner and outwardly, i.e. the centre hole of the spiral increases proy-ressively. Figs. 9b and c show embodiments in which the end 32 of the spiral is disposed for a gradual reduction of its blade height.
Material which is supplied to the apparatus 1 through the infeed opening 14 in the casing 2 is moved in a direction towards the dis~
charge opening 24 by rotation of the spiral 3, As will be apparent from Fig. 2, a gathering of material takes place in the precompaction zone 22 partly in that the spiral 3, in certain embodiments, has a smaller pitch than in the transport zone 21, and partly in that the movement of the material is braked in the compaction zone 23 and/or by the counterpressure members 8, 25, 26, 28, and 50. As a result, the material, in the compaction zone, as a rule substantially fills out the entire cross-section of the casing.
In Figs. 3, 4a, 4b, 4c and 5 braking is eFfected of the movement of the material in the compaction zone 23 by friction against the inner wall of the casing in the compaction zone (Fig. 3), by the action of the counterpressure plates 8a, 8b (Figs. 4 and 5), or by a combination of friction and pressure which is obtained in that the cross section (Fig. 3) of the casing diminishes, or alternatively in that the casing terminates in the cone 3~, (Fig. 4b).
In the embodiments illustrated in Figs. 6a and 6bl a reduction is e~fected of the liquid-content of the material, during passaye through the precompaction zone 2Z and the compaction zone 23. In many examples of physical application, the casing 2 is, in such instances, disposed such that the material is moved sliyhtly upwardly when it passes in a direction towards the discharye opening 24. Hereby, drainage of the material will be facilitated, since a portion of the liquid will pass in a direction opposite tot he direction of movenent of the material and substantially in the centre of the shaftless spiral, before the liguid runs out through the drainage openings 330 As a resu1t, it wi11 be possible for the liquid to reach the drainage openings of the casing in a region where the material has not yet had time to be compacted to any appreciable degree.

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On movement of material into the container 26 or into the hose 2 cf~ Figs. 7a and b), the container, the hose - or alternatively the hose in combination with the container - is proyressively forced out frorn the casing 2 by the action of forces from the material, at the same time as the material is compacted and then attains, as a rule, a degree of compaction which is in addition to the previously-attained compaction.
In the embodiment illustrated in Fi~s. ~a and b, the conveyor apparatus 50 constitutes a counterpressure member in that the dimen-sions~ pitch and speed of the spiral 53 have been selected such that the material is braked in its movement on passage out from the dis-charge opening 24 of the casing 2. There will hereby be obtained the desired compaction of the material when this is located in the casing 52 of the receiving combination, and thereby requisite filling of the casing of the receiving combination.
The above-described counterpressure members are, in certain embodiments, combined so that, for example, there will be included in one and the same apparatus, a counterpressure plate 8a, b and a termi-nating conical portion of the casing; a counterpressure plate 8a, b, and a shiftable receptacle member 26, 28: a cone 34 and the receiving casing 52 with spiral 53; and so on.
In certain physical applications of the invention, a braking of the material takes place in the precompaction zone to such a great extent that at least that section of the casing located most proximal the compaction zone will be as good as completely filled with material. The thus compacted material is thereaFter caused to leave casing through its discharye opening 2~ in batches whose size is determined by the rotation of the spiral (the angular alteration which the spiral undergoes), in COnJUnCtion with each discharge occasion. Hence, the present invention offers a simple and reliable technique for the batchwise discharge, with a relatively deyree of accuracy, of material from an apparatus according to the present invention.
The above detailed description refers only to a limited number of embodiments of the present invention., but the skilled reader of this specification will readily perceive that many modifications and embodiments of the present invention are conceivable without depart-ing from the spirit and scope of the appended claims.

Claims (39)

1. An apparatus for conveying and compacting material incuding fractions of different sizes, densities, elasticity and moisture content comprising a casing, at least one shaftless spiral disposed in said casing, supply means in said casing for feeding the material thereinto, drive means for rotating said spiral in said casing such that said spiral advances said material through said casing, said casing having an outlet towards which the material is advanced by said spiral, said casing including a first section in which said spiral extends with slight play, said spiral having a terminal free end disposed in said first section, said casing including an end section extending from said first section beyond said terminal free end of said spiral and comprising counterpressure means associated with said end section for opposing advance of said material in said end section to compact said material.

2. The apparatus as claimed in claim 1 wherein in said first zone said spiral has a pitch which diminishes towards the outlet of the casing.

3. The apparatus as claimed in claim 1 wherein the free end of the spiral has a blade height whose radial extent diminishes towards the end of the spiral.

4. The apparatus as claimed in claim 3 wherein the radial extent of said blade height diminishes continuously.

5. The apparatus as claimed in claim 3 wherein the radial extent of said blade height diminishes stepwise.

6. The apparatus as claimed in claim 1 wherein said counter-pressure means comprises a spring-loaded counterpressure plate movably journalled to said casing.

7. The apparatus as claimed in claim 6 wherein said counter-pressure plate is pivotably connected to said casing in said end section.

8. The apparatus as claimed in claim 6 wherein said counter-pressure plate is pivotally connected at said outlet.

9. The apparatus as claimed in claim 8 comprising a receptacle chamber at said outlet, said counterpressure plate being pivotally connected to said receptacle chamber.

10. The apparatus as claimed in claim 1 wherein said counterpressure means comprises a split cone including opposed spring-loaded members at said outlet.

11. The apparatus as claimed in claim 10 comprising a receptacle chamber at said outlet, said split cone being in said recepacle chamber.

12. The apparatus as claimed in claim 1 wherein said end section has a wall with an interior surface which comprises the counter-pressure means.

13. The apparatus as claimed in claim 12 wherein said end section is of uniform diameter.

14. The apparatus as claimed in claim 12 wherein said end section has a diameter which diminishes uniformly towards said outlet.

15. The apparatus as claimed in claim 1 wherein said counter-pressure means comprises a container on said end section displaceable axially of said casing under the pressure of the advancing material in said casing.

16. The apparatus as claimed in claim 15 wherein said container comprises a flexible hose.

17. The apparatus as claimed in claim 1 wherein said counter-pressure means comprises a second casing having an inlet means sealably connected to said outlet of the first said casing, and a shaftless spiral in said second casing, said second casing having a cross-sectional area at said inlet means which corresponds sub-stantially to the cross-sectional area of said first casing,

18. The apparatus as claimed in claim 17 comprising drive means for said shaftless spiral in said second casing.

19. The apparatus as claimed in claim 18 wherein said second casing is upright and has an outlet above the inlet means thereof.

20. The apparatus as claimed in claim 1 wherein said casing has drainage openings.

21. A method for conveying and compacting material including fractions of different sizes, densities, elasticity and moisture content, said method comprising:
feeding material which is to be advanced and compacted into the casing, advancing the material in said casing towards a discharge outlet thereof by rotating a shaftless spiral in said casing, the spiral terminating, at a free end thereof, at the end of a precompacting section of the casing in which the spiral extends with slight play, the material being advanced beyond said free end of the spiral through a compaction zone of the casing before being discharges at said outlet, and applying counterpressure to said material to oppose its discharge through said outlet to effect compaction of said material.

22. A method as claimed in claim 21 wherein said counterpressure is applied to said material in said compaction zone by walls of said casing.

23. A method as claimed in claim 21 wherein said counterpressure is applied to said material in said compaction zone from outside said casing.

24. An apparatus for conveying and compacting material including fractions of different sizes, densities, elasticity and moisture content comprising a first conveyor including a casing, at least one shaftless spiral disposed in said casing, supply means of said casing for feeding the material thereinto, drive means for rotating said spiral in said casing such that said spiral advances said material through said casing, said casing having an outlet towards which the material is advanced by said spiral, said casing including a first section in which said spiral extends with slight play, said spiral having a terminal free end disposed in said first section, said casing including an end section extending from said first section beyond said terminal free end of said spiral and connected to a second means having an inlet means connected to said outlet of said casing, and a shaftless spiral in said second means, the center axis of said shaft-less spiral of the second means being located and oriented so that material fed out through said outlet of said casing of the first conveyor is cut off by the shaftless spiral of the second means while the spiral of the second means is rotated.

25. The apparatus as claimed in claim 24 wherein said second means is a second conveyor.

26. The apparatus as claimed in claim 24 comprising drive means for said shaftless spiral in said second means.

27. The apparatus as claimed in claim 25 wherein said second conveyor has a casing having a cross-sectional area at said inlet means which corresponds substantially to the cross-sectional area of said casing of the first conveyor.

28. The apparatus as claimed in claim 27 wherein said casing of the second conveyor has an outlet below the inlet means thereof.

29. The apparatus as claimed in claim 24 wherein in said first section said spiral of the first conveyor has a pitch which diminishes towards the outlet of the casing.

30. The apparatus as claimed in claim 24 wherein the free end of the spiral of the first conveyor has a blade height whose radial extent diminishes towards the end of the spiral.

31. The apparatus as claimed in claim 30 wherein the radial extent of said blade height diminishes continuously.

32. The apparatus as claimed in claim 30 wherein the radial extent of said blade height diminishes stepwise.

33. The apparatus as claimed in claim 28 comprising a receptacle chamber at the outlet of the second conveyor.

34. The apparatus as claimed in claim 24 wherein said second conveyor forms a counterpressure means.

35. The apparatus as claimed in claim 24 wherein said casing of the first conveyor has drainage openings.

36. The apparatus as claimed in claim 35 wherein the drainage openings are placed in a region comprising said end section.

37. The apparatus as claimed in claim 35 wherein the drainage openings are placed in a region comprising the portion of the casing of the first conveyor which surrounds said terminal end of the spiral.

38. A method for conveying and unloading material from an apparatus, the material including fractions of different sizes, densities, elasticity and moisture content, said method comprising:
feeding material which is to be advanced into a casing of a first conveyor, advancing the material in said casing towards a discharge outlet thereof by rotating a shaftless spiral in said casing, the spiral terminating, at a free end thereof, at the end of a precompacting section of the casing in which the spiral extends with slight play, the material being advanced beyond said free end of the spiral through a compaction zone of the casing before being discharged at said outlet, the material which is discharged at said outlet being cut off from said outlet by rotating a shaftless spiral in a second means and the cut off material being advanced by said shaftless spiral of said second means towards an outlet of the second means to leave the apparatus at said outlet.

39. A method as claimed in claim 38 wherein said second means is applying counterpressure to said material to oppose its discharge through said outlet to effect compaction of said material.