GB2068520A

GB2068520A - Rotatable drying and separating drum

Info

Publication number: GB2068520A
Application number: GB8100989A
Authority: GB
Original assignee: Kockums Construction AB
Current assignee: Kockums Construction AB
Priority date: 1980-01-29
Filing date: 1981-01-13
Publication date: 1981-08-12
Also published as: DK13481A; FI804061L; BR8100299A; EP0033009A1; AU6607781A

Description

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GB 2 068 520 1

SPECIFICATION

A rotatable drying and separating drum

The invention relates to a device for a rotatable drying and separating drum for bulk goods, such 5 as chopped crops. The drum comprises a feed member for the goods to one end of the drum, a discharge member for a light fraction of the goods from the other end of the drum and an outlet device for a heavier fraction in between. The drum 10 is further adapted to pass air from one end to the other.

Rotatable drying and separating drums of the kind given in the introduction are previously generally known. Such a drum is described, for 15 example, in US 2 617 529. The outlet device in the shell of the drum consists, in this case, of an opening in the shell which is normally closed by a cover but which can be opened once for each revolution which the drum rotates, namely when 20 the opening is in the bottom position. This construction has some decisive disadvantages and limitations. As a result of the fact that the cover is opened only once per revolution, the discharge capacity is very small. Admittedly, this could be 25 increased bv increasing the number of openings, but then, on the other hand, the construction would become very complicated to guarantee the synchronism between the opening of the cover and the bottom position of the opening. In certain 30 cases, the most decisive disadvantage, however, is that goods which are ready to be discharged must wait up to a whole revolution before the discharge can take place. If the bulk goods consist of crops with grain which should be discharged 35 through the outlet device in the shell of the drum, this waiting for discharge may prove fatal if the temperature in the drum is so high that the grain can be damaged by being heated too long.

Another limitation in providing a flap as in 40 US 2 617 529 is that such a construction makes it more difficult to introduce a counter stream of air through the outlet, which stream of air may be desirable to prevent husks or other light parts from accompanying the grain out through the outlet. ' 45 The object of the invention is to offer an outlet device for a rotatable drying and separating drum, which renders possible a very rapid discharge of - the goods which have been conveyed forwards for discharge to the section in the drum where the 50 outlet device is situated.

Accordingly the present invention provides a rotatable drying and separating drum for bulk goods, having a feed member for the goods to one end of the drum, a discharge member for a lighter 55 fraction of the goods from the other end of the drum, an outlet device for a heavier fraction between said feed and discharge members; and means for flowing air through the drum; wherein the outlet device comprises a continuous outlet 60 opening, or a series of separate outlet openings, which extends round the periphery of the drum and is surrounded by a stationary cover extending round the drum outside said outlet opening or series of outlet openings; and wherein the cover is adapted substantially to close the opening or series of openings over the major portion of the periphery so that the discharge of goods and the inlet or discharge of air through the opening or openings is substantially prevented when the opening or series is within said region of the cover, but that within the remaining sector outside said region, goods and air can pass through the portion of the opening or series present there.

Goods which have been conveyed forwards for discharge to region in register with the outlet device shall also be discharged immediately so as not to remain in the drum unnecessarily. For this purpose, the outlet device may appropriately be adapted to cooperate with the feed member which quickly feeds the grain or corresponding goods to the region in front of the outlet device.

Preferably the heavier fraction, for example grain or corresponding goods, is substantially prevented from rotating with the drum for another revolution or part of a revolution as soon as the goods intended to be discharged have been fed forwards to the region in register with the outlet device.

It is also an object to be able to direct a stream of air in the opposite direction to the discharge direction for the heavier fraction, for example grain, so as to blow away any remaining lighter fraction, for example husks or straw components, from the heavier fraction.

Advantageously said remaining sector of the outlet opening comprises mainly only the lower right hand quadrant of the circle in an imaginary section through the drum at right angles to the axis of rotation of the drum with the drum rotating in counter-clockwise direction. Said opening may appropriately consist of a gap which extends substantially round the whole periphery of the drum between two sections of the drum, the two sections being connected together by a plurality of intermediate members in and/or outside the gap, which intermediate members have a small extent in section parallel to the shell of the drum. Said intermediate members preferably have the form of rails shaped like the rails of an impeller directed outwards and backwards in relation to the direction of rotation. Various aspects of the device described hereinafter are also described in our copending British Patent Application No. 80 Publication No.

In the following description of a preferred form of embodiment reference is made to the accompanying drawings, in which

Figure 1 constitutes a side view of an integrated primary drier, threshing mechanism and separating mechanism for chopped cereals.

Figure 2 constitutes a section II—II in Figure 1.

Figure 3 constitutes a section III—III in Figure 2.

With reference to Figure 1 the numeral 1 designates a rotatable drum which constitutes an integrated primary drier, threshing mechanism and separating mechanism for chopped cereals. A mixing chamber for drying air is designated by 4. A feed pipe 5 is adapted to feed the chopped but

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otherwise untreated crops into a primary drier 6, which is connected to a separating section 7. Between the primary drier 6 and the separating section 7 there is an outlet device, generally 5 designated by 8, for grain. The primary drier 6 and the separating section 7 together form the coherent rotatable drum 1 which has a horizontal axis of rotation. The drum 1 is adapted to be rotated about the horizontal axis of rotation by a 10 drive motor 61. The drum 1 rests against two pairs of rollers 62 which are supported by a base 64 via bearing brackets 63. The pipes for introducing drying air into a mixing chamber 4 are designated by 54 and 55 while a lock for the crops 15 is designated by 13. Disposed in the other discharge end of the drum 1 is a discharge box 14 for straw, chaff and other lighter components of the crops. The outlet device 8 for grain is connected, via a lock 34 and a pipe 9, to a grain 20 drier not shown. Further disposed above the lock 34 is a pipe 10 for the introduction of air into the outlet device 8. A damper in the pipe Wis designated by 11.

In the region in front of the outlet device 8, the 25 drum 1 has an opening 12, Figures 2 and 3. The opening 12 consists of a gap between the drying section 6 and the separating section 7. The gap is unbroken which means that the opening 12 extends round the whole periphery of the drum. 30 Outside the opening 12 there is disposed an annular construction 15. This consists of two angle irons 16 and 17 which have been bent into ring form with the webs of the iron facing one another and with the arms facing away from one 35 another as seen in Figure 3. Disposed between the . irons 16 are a plurality of rail-shaped intermediate members 18, a pair of which are designated by 18A and 18B in Figures 2 and 3. Each intermediate member 18 extends from the outside 40 of the drum 1 to the tip of the right angle of the angle iron. At the same time, each intermediate member 18 extends uniformly backwards in relation to the direction of rotation of the drum 1. The direction of rotation is designated by arrow A, 45 Figure 2. The intermediate members are also somewhat convex as a result of which the construction 15 has an appearance reminiscent of an impeller or a water-wheel. The annular construction 17 thus formed is welded to the 50 outside of the drum 1 over the opening 12 and so connects the drying section 6 and the separating section 7.

Disposed outside the ring 15 is an outlet cover, generally designated by 19. The purpose of the 55 cover 19 is to shield the opening 12 from the environment and to connect the opening 12 to the discharge pipe 9. The outlet cover 19 comprises a discharge box 20 disposed outside the ring 15 within the sector of a circle which corresponds to 60 the fourth quadrant of the circle with respect to the direction of rotation of the drum 1, Figure 2. The box 20 also covers a small portion of the end . of the fourth quadrant of the circle. The box 20 is formed of front and back plates 21,22 and a pair 65 of side plates, and the back and front plates 21,

11 converge to match the shape of the discharge pipe 9. Extending round the main portion of the ring 15 there is also a sheet-metal strip 23. The „ covering strip 23 is disposed at a very short 70 distance from the ring 15 so that there is a narrow gap 24 between the covering strip 23 and the two_ arms 16B and 17B of the ring 15. The covering " strip 23 is connected, by its longitudinal edges, to the outer ends of the web 25A and 26B on a pair 75 of angle irons 25 and 26 respectively. The angle irons 25,26 extend around the first and second quadrants of the circle. Figure 2, as well as the main portion of the third quadrant and their ends are also connected to a pair of portions 27 and 28 80 of the front and back walls 21 and 22 respectively of the outlet cover 20. The irons 25 and 26 together with.extensions 27 and 28 are also connected to one another by a plurality of bolts 29. The outlet cover 19 thus formed is mounted 85 on the base 64 in a manner not described in the Figures. The discharge box 19 is thus mounted fixed in space while the drum 1 together with the ring 15 is adapted to be able to rotate inside the discharge box 19. In order to seal the cover 90 against the environment, a pair of rubber seals 30, 31 are disposed between the angle irons 25 and 16 and between the angle irons 26 and 17 respectively.

Inside the drum 1 there are also members for 95 feeding grain towards the outlet opening 12. Both the drying section 6 and the separating section 7 may appropriately be provided with such feed members which can have the form of a screw-shaped conveyor 32, Figure 2. Figure 2 also 100 shows a plurality of pin-shaped members 33

distributed along the spiral conveyor 32 to prevent straw and other unwanted components from being conveyed towards the discharge opening 12. As a result of the rotation of the drum, the 105 grains also tend to accompany the drum up the walls in the direction of rotation to a certain extent. At the same time, however, they fall down by their own weight and are forced by the spiral conveyors 32 towards the outlet opening 12. The 110 total effect is that the grains accumulate in the part of the drum which corresponds to the fourth 5 quadrant of the circle when the drum is considered in the axial direction and the drum rotates in counter-clockwise direction. Figure 2. ? 115 Thus the grains, which are generally designated by 36 in Figure 2, reach the discharge opening 12 in the region in front of the discharge box 20. In this region, the intermediate members 18, such as the intermediate member 18C, are at first 120 substantially horizontal to be adjusted more in the vertical direction at the end of the discharge box 20, that is to say when the intermediate members approach the front wall 21. This means that before each intermediate member 18, such as the 125 intermediate member 18D, leaves the outlet cover 20 in counter-clockwise direction, the intermediate member 18D in question together with the next following intermediate member 18E form a substantially vertical chanel 35A between 130 them. The next following channel 35B is less

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pronouncedly vertical while the following channel 35C is not so at all. Airflows in the direction of the arrows B through all the channels 35A, 35B and 35C, which are constantly displaced to make 5 room for new intermediate members 18 and new intervening channels. Through the first channel 35C, where the flow of grains is comparatively little in view of the fact that the intermediate members 18C and 18D are more or less 10 horizontal, the flow of air thus has an almost pure separating effect in that the air blows away any remaining husks and other lighter particles which have accompanied the grains to the discharge opening 12. The stream of air likewise has a 1 5 separating effect in the following openings 35B and 35A, but the primary function of these openings is to discharge the grains 36 which also takes place very effectively because there the openings 35A and 35B are disposed nearly 20 vertically.

Claims

1. A rotatable drying and separating drum for bulk goods, having a feed member for the goods to one end of the drum, a discharge member for a 25 lighter fraction of the goods from the other end of the drum, an outlet device for a heavier fraction between said feed and discharge members, and means for flowing air through the drum; wherein the outlet device comprises a continuous outlet 30 opening, or a series of separate outlet openings, which extends round the periphery of the drum and is surrounded by a stationary cover extending round the drum outside said outlet opening or series of outlet openings; and wherein the cover is 35 adapted substantially to close the opening or series of openings over the major portion of the periphery so that the discharge of goods and the inlet discharge of air through the opening or openings is substantially prevented when the

40 opening or series is within said region of the cover, but that within the remaining sector outside said region goods and air can pass through the portion of the opening or series present there.

2. A drum as claimed in claim 1, wherein said

45 sector substantially only comprises the lower right hand quadrant of the circle in a section through the drum taken at right angles to the axis of rotation of the drum and with the drum rotating in counter-clockwise direction.

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3. A drum as claimed in claim 1 or 2, wherein there is one said continuous discharge opening which consists of a gap extending round substantially the whole periphery of the drum - between two sections of the drum, and the two

55 sections are connected together by a plurality of intermediate members in and/or outside the gap, which intermediate members have a small extent when viewed in a section parallel to the shell of the drum.

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4. A drum as claimed in claim 3, wherein said intermediate members are in the form of rails,

such as the rails of an impeller, directed outwards and backwards in relation to the direction or rotation.

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5. A drum as claimed in claim 4, wherein the channels between said rails are adapted to pass air in a direction towards the goods which are, in use of the drum, discharged through the same channels.

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6. A rotatable drying and separating drum substantially as hereinbefore described with reference to, and as illustrated in, the accompanying drawings.

Printed for Her Majesty's Stationery Office-by the Courier Press, Leamington Spa, 1981. Published by. the Patent Office, 25 Southampton Buildings, London, WC2A 1AY, from which copies may be obtained.