The present invention relates to a device for transporting a product, said device comprising a tube which is rotatable about a central axis.

Such a device is generally known in the art.

The object of the present invention is to provide an alternative device .

To this end, a device according to the preamble is characterized in that the tube comprises a plurality of sections distributed along the circumferential direction of the tube, which tube is rotatable about a central axis and the sections are arranged to consecutively bring the sections

- in a relatively high position of a section in a retracted position, and

- in a relatively low position of the section wherein the product may be lying on the section to an extended position.

Thus, it is possible to transport a product, such as a (viscous) liquid or a particulate product (eg. a powder or granulate) .

The number of sections will at least be two, in general at least four and preferably six or more.

The sections are usually in axial direction of the tube oblong sections .

The sections, which are for instance in the form of plates such as curved plates, may be provided with ribs and/or grooves which extend with an axial directional component in the tube such as for entraining the product in the direction of rotation. This can

contribute to mixing or to carrying out a process in the device. That process is for instance a drying process wherein water vapour is discharged via the lumen of the tube, or a process wherein the product is brought into contact with an agent that is passed through the lumen of the tube .

The tube comprises an inlet end and a discharge end. By reversing the direction of rotation it is possible to reverse the direction of transport, in which case the inlet end can be the discharge end.

The central axis is usually the centreline of the tube.

According to a favourable embodiment, the device is a device for mixing the product . Such a device is suitable for the simultaneous transport and mixing of the product. The product to be transported and to be mixed will then be a liquid or a particulate product. The mixing may be the mixing of a particulate material having different particle sizes and/or at least two particulate materials having different chemical compositions. The mixing may also be the mixing of a particulate material with a gas or liquid.

According to a favourable embodiment, the sections are in the form of plates.

The plates are for instance plates that are curved, wherein the concave side is facing the centreline of the tube and runs parallel therewith .

According to a favourable embodiment, the plates present an overlap at sides where they are ajacent to each other.

Thus, leakage of product can be limited or prevented. Herewith it is preferable that a plate that runs ahead in the direction of revolution to an adjacent plate has a side that has an overlap with that adjacent plate. Thus, the risk that a particulate product ends up between the side edges of the plates is effectively reduced. The overlap that extends from a section and overlaps an adjacent section will generally extend in the circumferential direction of the tube over at most 180°, for instance over less than 90° and advantageously at least 2 ° .

According to a favourable embodiment, the tube comprises over at least a portion of its length a tubing of elastomeric material.

Thus, a seamless tube can be provided. This offers a simple construction wherein no product will end up between sections.

The tubing comprises an end section which according to an advantageous embodiment at the discharge end of the tube is wrapped around a guide ring and extends parallel with the mid section of the tubing. The end of the end section is fixed. By moving the tube sections of the mid section to and away from the guide ring,

transportation of the product is possible, when the whole of the tubing with fixed end and guide ring is rotated about the central axis.

The distance from the fixed end of the tubing to the end of the tube as defined by the guide ring will in a non-stretched state generally be at least 3% of the length of the tube, preferably at least 8% and more preferably at least 15%.

The distance from the fixed end of the tubing to the end of the tube as defined by the guide ring will in a non-stretched state generally be at least 1 cm, advantageously at least 3 cm.

According to a favourable embodiment, the device comprises a frame and an element selected from

i) the frame, and

ii) the sections

is provided with a guide for cams and the other element is provided with cams which cooperate with the guide, wherein the guide and the cams extend in circumferential direction around the central axis and one item selected from

i) the guide and

ii) the cams

defines a path comprising a path section which is located at a relatively high location, relatively close to a supply opening of the tube and a further path section at a relatively low location which is located relatively far from the supply opening.

Thus, by rotating the tube with respect to the frame the desired movement of the sections can be achieved for transporting product in the tube. This embodiment makes it possible to abstain from individual actuators for moving the sections.

For a simple construction the elements will be situated at the outer circumfential side of the tube. The guide is for instance in the form of a slot. The guide may, however, also be a protruding element wherein the cams engage around the guide.

Thus, it is for instance possible to simply move (slide in axial direction of the tube) the sections, which for instance are in the shape of plates (curved or not curved) using a helical rail and cam rolls in conjuction with the rotating movement of the tube. The helical rail provides a guide for the cam rolls. The helical rail closes onto itself and is thus an endless guide.

The path, which is an endless path, comprises for instance a first section having a first pitch, and a second (usually shorter) section having a second pitch, which second pitch has an opposite sign

(and if shorter then also is a larger pitch) . The first pitch is for instance left-handed and the second pitch right-handed (or the other way around), whereby the path is closed. The cams (or with less preference the guide) may also extend at the inside of the tube from the inner wall of the tube. In that case a feed pipe protruding into the tube may have a double function, namely feeding material to be transported, and providing the complementary element (the guide or optionally the cams) at the outer wall of the feed pipe .

According to yet another embodiment the cams may extend in axial direction and will typically be located at the end of the tube, advantageously at the first end (supply end) .

According to a favourable embodiment, the path in a path section thereof that is situated the lowest has a constant pitch for moving at least two sections of the tube simultaneously and at the same speed.

Said at least two sections of the tube will then be the sections on which the product will lie (and essentially not on any other sections) during use of the device. This will contribute to moving the product in the tube at a constant speed and permits moving all product lying on sections at the same speed, as a result of which no mutual speed differences are present between product lying on adjacent sections (wherein the adjacent sections are sections of the at least two sections) .

According to a favourable embodiment, the sections at at least one discharge end of the tube have an edge that runs parallel with the pitch of the section of the path that is situated the lowest.

Thus, a very uniform discharge of material from the tube can be realized.

In case of curved plates, these will be cut off at the end of the device in such a way that they will form an even helical entity.

The invention can be realized in various ways. According to a set of possible embodiments the device comprises three separate

component s :

1. A support structure with drive for a cylinder construction and an inlet and outlet for the product.

2. A cylinder construction that holds the internal curved plates. 3. Curved plates.

Support construction: This contains guides and a drive that lets a cylinder construction rotate, horizontally, about its axis. This is _n

5

made such, that the frontside and backside of this cylinder

construction are freely accessible. This frontside and backside contain the inlet channel and outlet channel. The cylinder

construction can rotate, but can not slide forward or backward.

Guiding can take place by means of guiding wheels, rollers or by means of gliding strips over which the cylinder construction runs. A large ball bearing having an inner diameter greater than the cylinder construction may also work. Driving can take place by driving one or more wheels, or by placing a chain around the cylinder construction which in turn is driven by a gear wheel, or by a gear rack fitted around the cylinder construction which in turn is driven by a gear wheel .

It should also be possible to fit the helical rail, as described later, into this support structure. Furthermore, the support structure may be insulated in order to guarantee certain process conditions. Of course, in that case, the accessability should be taken into account in view of maintenance and cleaning of the machine.

Inlet channel: Since the product is pulled downward by gravity, the product stream will hardly be affected by the curved plates above. Thus, transporting the curved plates forward can be stopped. During this period the curved plate can be drawn backwards. Because of the rotating movement of the interior assembly this period may be

translated to space. In connection with the inlet channel the

withdrawal can only take place in a limited part of the space

described above. In the remaining part of this space the inlet channel will then have to be fitted in, as running into the curved plates during withdrawal or inlet of these curved plates is undesirable. It should be noted that this limitation of space only applies directly to the inlet wall, further to the back there is space for a wider transport channel.

The curved plates drum is sealed off from the support structure by an inlet wall. This has to be tight-fitting in order to prevent leakage. This inlet wall contains a cut-out in which the inlet channel ends up. The inlet channel and inlet wall are attached to the support structure. It should be noted that multiple inlet funnels may end up in the machine in order to mix material in this way. Also one or more conduits can be passed through the inlet wall in order to get steam or liquid in the machine. Furthermore, the inlet wall may be used for _r

b

allowing the escape of medium if the apparatus is used as a

counter-current cooler. It is also an option to have one or more conveyor belts end up in the drum in order to get material into the machine and have this mixed.

Outlet channel: This can be constructed in a rather simple way without limitations . Namely, by creating a container around the curved plates which using a funnel shape results in the desired shape. A seal at the outside of the curved plates that functions well should be taken into account . The container must be long enough to allow for the backward and forward movement of the curved plates.

Cylinder construction: This consists of a cylinder-shaped construction. It contains the curved plates. The cylinder construction has to be reasonably rigid and hardly sag or change shape or location in other ways during rotating, transporting, cooling or mixing. The cylinder construction is guided and driven as already described hereinabove. The curved plates will be held by the cylinder

construction so that they can only move in an axial direction with respect to this cylinder construction. This may take place by making slots in the cylinder construction whereby sliders at the outside of the cylinder construction hold the curved plates. Optionally, also other existing linear guides may be used.

In order to counteract contamination, at the locations where the curved plates meet in the cylinder construction recesses may be provided in the cylinder construction. Thus, any leakage of the product in this way will then end up in the support structure, and not remain between this cylinder construction and the curved plates, hindering the operation. Curved plates: These consist of a tube which in the horizontal

(axial) direction is divided into a number of curved plates. The sides of the curved plates may be designed such, that they will overlap each other, or form a labyrinth system, keeping leakage of the product present in the interior to a minimum. The curved plates may be cut off helically at the outlet to guarantee a continueous outlet of the product. In the curved plates additional ribs may be mounted in the axial direction in order to let the product roll around better and thus mix better. As described above these curved plates are fixed such, that in the cylinder construction they can shift forward and backward. This shifting forward and backward takes place during the rotating of the cylinder construction and can be arranged for by a cam roll that is fixed to the curved plate and extends through the cylinder

construction. To this end, separate recesses have been provided in the cylinder construction. This cam roll runs along a helical rail, that is mounted in the support structure. The displacement of the curved plate can optionally also be achieved in other ways. For instance by means of a linear motor, a pneumatic cylinder or a hydraulic cylinder.

All curved plates shift forward simultaneously, at one particular point one curved plate is drawn backwards by means of the cam roll or by means of another external force. This external force may be brought about by placing springs between the cylinder construction and the curved plates. This force may also be generated by pneumatic

cylinders, hydraulic cylinders or linear engines.

At the inlet side there is an inlet channel which puts the product directly into the tube. While turning, the curved plates shift forward simultaneously and the curved plate is at the top, and upon which thus no force is exerted by the product, can be drawn backwards. The movement is thus continued jerk-free for the product present in the curved plates. At the outlet side an outlet channel is present that discharges the product.

The assembly may or may not be arranged at a positive or negat angle, to accelerate the product, to slow it down or just to oppose the continuity of the flow to migrate and thus to obtain better mixing .

Some possible applications:

1. A closed, insulated means for transport.

2. A retention vessel to create a conditioned time of residence.

3. A dosing device to pull product directly from a bunker .

4. A continuous mixer for different solids.

5. A continuous mixer for solid and liquid.

6. A continuous mixer for solid and steam.

7. A counter-current cooler. The tube consisting of curved plates should be filled completely, in which case a cooling material may be ₀

o

pushed from the discharge end in a direction opposite of the product stream.

Some possible advantages compared to other mixers and means of transport .

1. A constant product stream.

2. If desired arranged at a neutral angle, the system offers a guaranteed first-in-first-out=principle for the product.

3. No parts such as axles or paddles in the tube, for which reason there will be minimal contamination.

4. Degree of filling of the tube can very high be and is

predictable .

5. Since the product rolls very constantly through the tube to the front, it will roll from the tube in constant manner at obliquely cut helical ends of the curved plates also.

The present invention will now be illustrated with reference to the drawing where

Fig. 1A and Fig. IB respectively show a top view and a rear view on a device according to the invention;

Fig. 2A and Fig. 2B show two cut away perspective views of the device of Fig. 1A;

Fig. 3A and Fig. 3B show cross-sectional views through the device of Fig. 1A;

Fig. 4a shows a perspective detail of an end of the device of fig. 2B; and

Fig. 4B shows a perspective detail of an alternative end of the device of Fig. 2B.

Fig. 1A and Fig. IB respectively show a top view and a rear view of a device 100 according to the invention.

The embodiment of a device 100 discussed here comprises a housing 101 that functions as a frame. The housing comprises a lower housing section 101a and an upper housing section 101b which are connected to each other by means of socket-head screws 102.

The device 100 comprises a motor 103 for driving a tube 110 which tube 110 is provided at the outer circumference thereof with cam rolls 120 which cam rolls 120 are passed along a guide 130 defined by two stationary rings 131. _n

y

The inlet end 111 of the tube 110 and the discharge end 112 thereof are visible.

The tube 110 is made up of sections 115, here six sections 115 in the form of curved plates 115. The sections 115 can be displaced in the axial direction of the tube 110 with respect to each other.

The tube 110 is surrounded by a sleeve 140 which at the inner circumference thereof is provided with guiding rods 141 for the sections 115 extending in the axial direction of the tube 110. As will be be explained hereinafter the totality of the tube 110, the guiding rods 141 and the sleeve 140 is rotated about a central axis of the tube 110. The sleeve 140 comprises two spaced apart sleeve sections (first sleeve section 140' and second sleeve section 140") . The cam rolls 120 are attached to the sections 115 and project between both sleeve sections, with the distal end of the roller cam pins 120 in the guide 130. By rotating the sleeve 140 the sections 115 are entrained in the circumferential direction. By means of the (stationary) guide 130 the sections 115 are moved in the axial direction. This happens such that once a section 115 is relatively high said particular section 115 is moved from a position wherein the section is in a relatively extended state to a state in which the section is in a relatively retracted position state (closer to the inlet end) . In the relatively high position there is no material to be transported, such as a powder or granulate, on the section. During the further movement of the roller cam pin of said section, the section is moved to a relatively extended position again by means of the guide 130, wherein material that ended up on the particular section 115' by rotation of the tube 110 is moved.

Fig. 2A and Fig. 2B show two cut away perspective views of the device 100 of Fig. 1A.

In Fig. 2A the upper housing section 101b and the motor 103 have been omitted. A gear wheel 240 that is connected to the sleeve 140 as well as a transmission 204 for rotating the tube 110 by means of the motor 103 are visible.

Fig. 2A shows a ball bearing 241 that engages the sleeve 140 and allows for rotation of the tube 110 with little friction. In addition, Fig. 2A shows the locations where the guiding rods 141 are secured to the sleeve 140 by means of bolts.

In Fig. 2A it is shown that the path defined by the guide 130 ₁

- comprises a first path section 130' where it forces in a relatively high position of the section the roller cam pin 120' thereof, and thus the section 115, to a retracted state, and

- comprises a second path section 130", here the remainder of the path, that has a gradual pitch (having the opposite sign) that brings the relatively retracted section of the tube gradually in a relatively extended state.

Compared to Fig. 2A, in Fig. 2B in addition ball bearing 241 and some of the sleeve 140 (in particular sleeve section 140") have been omitted in order to offer a view on the tube 110 and the guiding rods 141.

Fig. 3A shows a vertical longitudinal sectional view and Fig. 3B a horizontal longitudinal sectional view through the device of Fig. 1A. A hopper 305 into which a product to be transported can be brought that may be passed by means of the tube 110 of the device to the discharge end 112 by rotating the tube 110 about its central axis by means of the motor 103.

In case the device 100 according to the invention is to be used for carrying out a treatment of a material present in the tube 110, a fluid, such as a gas may be supplied via the hopper 305 (co-current) or discharged from it (counter-current) . The treatment is for

instance, drying, cooling or heating, for instance with a gas such as with air. The treatment may also involve supplying an agent such as a reagent .

With the device according to the invention the speed of transport may be controled in one or more ways, such as by the varying of the speed of revolution of the tube 110, the angle that the central axis of the tube 110 makes with the horizontal (which angle if desired can be varied dynamically, depending on what is necessary) , and the guide 130.

Fig. 4A shows a perspective detail of an end of the device 100 of Fig. 2B.

Here the ends of the elements 115 at the second end (discharge end) are cut transverse to the centreline of the tube 110. As a result, the edges 415 of the elements 115 protrude to different degrees at the second end 112, depending on their location along the path defined by the guide.

Fig. 4B shows a perspective detail of an alternative end of the device 100 of Fig. 4A. Here the ends of the elements 115 at the second end (discharge end of the device 100) are cut obliquely, wherein the oblique edge 415' runs parallel with the pitch that brings the elements 115 gradually from the retracted second position to the extended first position. In this embodiment the edges 415' at the second end of the lower elements 115 are in register (lie in line with each other) , making a more even discharge of product transported with the device 100 possible compared to the stepped end of the embodiment discussed for Fig. 4A.