The invention relates to a conveyor device comprising a conveyor belt having a conveyance surface for conveying in a conveyance direction along a conveyance path.

In practice quite some conveyor systems and conveyor belts are known for conveying objects along for instance treatment stations.

There are for instance toothed conveyor belts by means of which the movement of objects in the conveyance direction can be accurately determined. There are also conveyor devices having belts consisting of links for conveying for instance foodstuff.

From EP-A1-239. 660 a so-called conveyor belt is known, provided with a belt consisting of a carrier layer of a textile that is tensile strain resistant on which a flexible lagging is glued which is provided with wear-resistant elements that are incorporated in there and which extend over the surface of the conveyor belt in order to thus result in a wear-resistant layer. This conveyor belt is drawingly driven. A problem of this conveyor belt is that a bend can hardly, if at all, be made, particularly a bend in the horizontal plane.

From US patent 4.040. 302 a chain conveyor is known on which pallets can be transported in a conveyance direction along a conveyance path. Separate pallets are here conveyed on two driven chain conveyors. No conveyance surface is offered here for conveying along a conveyance path.

US patent application US-A1-2002/0148708 regards a conveyor device made of strips that are mutually hinged to one another. Here as well a bend in the horizontal plane can hardly, if at all, be made.

A problem of the known conveyor devices is that realising changes of direc- tion of the conveyance direction, particularly bends in the horizontal plane, is a problem.

It is an object of the present invention to offer an alternative conveyor device.

In addition it is an object of the invention to provide a conveyor device which solves at least a part of the problems of existing conveyor devices.

To that end the invention provides a conveyor device comprising a conveyor belt having a conveyance surface for conveying in a conveyance direction along a conveyance path, wherein the conveyor belt comprises elastically compressible elements.

The invention offers an alternative conveyor device.

By equipping the conveyor device according to the invention with a conveyor belt provided with elastically compressible elements, a conveyor device having new user options is created, particularly a conveyor device by which means it is possible to easily realise changes of direction of the conveyance direction, particularly bends, and more particularly bends in the horizontal plane.

Differences in height as well, possibly combined with changes of direction in the horizontal plane, can easily be realised with the conveyor device according to the invention.

In addition the conveyor device according to the invention offers the possibility to realise a conveyance surface on the conveyor belt wherein the position of objects on the conveyor belt during conveyance does not change or hardly changes.

Particularly in bends and changes of height it becomes possible to offer a conveyor device wherein the position of objects on a conveyor belt hardly changes, if at all, particularly the position of objects with respect to each other on the conveyor belt. This will result in large production technical advantages.

In addition due to the simple structure, very many drive possibilities can be used in such a conveyor device according to the invention.

In one embodiment of the conveyor device according to the invention the elastically compressible elements are elastically compressible in the con- veyance direction.

In one embodiment the conveyor belt forms a circulating, closed belt, preferably having a practically closed conveyance surface.

In one embodiment of the conveyor device when it is operative, the compressible elements are at least partially compressed in the conveyance direction.

In one embodiment the compressible elements are elastically compressible synthetic or plastic elements. In an embodiment thereof the compressible elements are made of an elastic, foamed synthetic or plastic material. The compressible elements particularly are substantially block-shaped having a width practically equal to the width of the conveyor belt.

In one embodiment of the conveyor device according to the invention it is

furthermore provided with a guide for guiding the conveyor belt along the conveyance path.

In one embodiment of the conveyor device according to the invention, the conveyor belt is further provided with elements that are bend stiff in the plane of conveyance. In an embodiment thereof, said elements comprise plate parts, having their surface in the conveyance direction. The plate parts have been arranged between the compressible elements. In a further embodiment the plate parts have been provided with an extension to offer engagement to a drive. In another embodiment the plate parts have means to cooperate with the guide. In a preferred embodiment the rigid elements have both means to offer engagement to a drive and means to cooperate with the guide to guide the conveyor belt along the conveyance path.

In one embodiment of the conveyor device according to the invention, the longitudinal axes of the rigid elements are situated along the width of the conveyor belt, and can be mutually moved in the conveyance direction.

In one embodiment of the conveyor device according to the invention, the rigid elements alternate with the compressible elements.

In one embodiment of the conveyor device it has alternately rigid elements and compressible elements.

In one embodiment of the conveyor device according the invention, the compressible elements form compressible segments in the conveyor belt.

In one embodiment of the conveyor device according to the invention, the conveyor belt has a conveyor belt width, over which the compressible synthetic elements substantially extend.

In one embodiment of the conveyor device according to the invention, the

compressible synthetic elements have an element width and an element length in the conveyance surface, wherein the compressible synthetic elements in the conveyance surface are practically contiguous for forming a practically continuous, contiguous conveyance surface.

In one embodiment of the conveyor device according to the invention, rigid elements extend in the conveyor belt width between the compressible synthetic elements, which rigid elements are rigid in the conveyance direction. In an embodiment thereof the rigid elements have an abutment surface between the compressible synthetic elements that extends over nearly the conveyor belt width.

In one embodiment of the conveyor device according to the invention, the conveyor device is furthermore provided with a drive for driving the conveyor belt, and the rigid elements each comprise at least one engagement member onto which the drive is able to engage for driving the conveyor belt.

In one embodiment of the conveyor device according to the invention the drive of the conveyor belt is adapted for pushing driving the conveyor belt.

The invention furthermore relates to a conveyor device provided with a plane of conveyance for conveyance thereon along a conveyance path, comprising: - a supporting frame; - a circulating conveyor belt having a conveyance surface as plane of conveyance, and - a drive for pushing driving the conveyor belt, wherein - the supporting frame is provided with a guide for guiding the conveyor belt along the conveyance path; - the conveyor belt in the conveyance direction comprises alternating in conveyance direction compressible elements having at least one stop transverse to the conveyance direction, having surfaces which in cooperation

substantially form the conveyance surface, and for at least 10 % compressed in the conveyance direction, and rigid elements provided with an engagement member for having the drive engage onto it in order to when operative exert a driving force onto it in the conveyance direction in order to propel the conveyor belt when operative, with a guide member in order to in cooperation with the guide, guide the conveyor belt along a conveyance path, and with a longitudinal axis transverse to the conveyance direction, and displaceable with respect to each other.

In an embodiment thereof the angle between the longitudinal axes of the rigid elements is changeable parallel to the plane of conveyance when the conveyor device is operative, during conveying, for making a bend.

The invention further relates to a conveyor device comprising a conveyor belt having a conveyance surface for conveying in a conveyance direction along a conveyance path, wherein the conveyor belt comprises compressible segments.

In one embodiment of such a conveyor device, the conveyor belt furthermore comprises rigid elements between the compressible segments, provided with engagement members for offering an engagement to a drive of the conveyor belt, guide members for offering an engagement to a guide in order to guide the conveyor belt along the conveyance path, and stop members for transmitting a driving force from the drive onto the compressible segments.

In one embodiment of such a conveyor device the compressible segments in the conveyor belt are compressed in the conveyance direction.

The invention further relates to a synthetic part, suitable and intended for use as a compressible synthetic element in a conveyor belt in a conveyor device as described above or shown in the drawings, having a practically closed conveyance surface that extends over the length and the width and having

two stop surfaces from the plane of conveyance, wherein the plane of conveyance of the synthetic part, when compressed, for 50% at the most along the length, deforms less than 10% of the height of the synthetic part.

In one embodiment the synthetic part is substantially made of a foamed synthetic material having substantially closed cells.

The invention further relates to a connection part, suitable and intended for use as rigid element in a conveyor belt in a conveyor device as described above or shown in the drawings, comprising a rigid plate part having stop surfaces on both sides, and at both ends provided with engagement members onto which a force perpendicular to the stop surfaces is able to engage, guide members onto which a force in the plane of the plate part is able to engage, and spacers which extend from the plane of the plate part.

In one embodiment of the connection part it is substantially made of metal, preferably selected from the group of aluminium, iron and steel that may or may not be stainless steel.

In a further embodiment of the connection part, it is substantially made of a rigid synthetic material, preferably selected from the group of PVC, polycar- bonate, nylon, that may or may not be reinforced with fibres, such as wood, carbon fibre, glass fibre, aramid or a combination thereof. Certainly in combination with the synthetic parts as described above, the conveyor belt can be made very lightweight and mass-produced.

The invention further relates to a conveyor belt having a conveyor belt length and width, comprising alternating segments that are compressible in the conveyor belt length as result of which the length of the conveyor belt can be changed with rigid elements in between, bend stiff in the plane of con- veyance, wherein the conveyor belt has a substantially closed conveyance surface.

The invention will be further elucidated on the basis of exemplary em- bodiments of conveyor devices according to the invention, in which: Figure 1 shows an embodiment of a conveyor device according to the invention seen diagonally from above; Figure 2 shows a top view of a conveyor device with a rack-and-pinion drive; Figure 3 shows a cross-section of the conveyor device according to figure 1 perpendicular to the conveyance direction; Figure 4 shows a combination of a compressible element and a rigid element ; Figures 5A-5C show an assembly of the compressible elements and the rigid elements with the compressible elements free (5A), compressed (5B), and in a bend (5C); Figures 6-10 show various embodiments of the compressible element; Figures 11-27 show various embodiments of the rigid elements; Figure 28 shows a conveyor device according to the invention with a rack- and-pinion drive; Figure 29 shows a conveyor device according to the invention with an alter- native rack-and-pinion drive; Figure 30 shows the conveyor device according to the invention provided with a friction-based drive; Figure 31 shows a conveyor device according to the invention provided with

a synchronous-belt or toothed belt drive; Figure 32 shows a conveyor device according to the invention provided with a magnetic drive; Figure 33 shows a conveyor device according to the invention provided with a sprocket drive; Figures 34A-C show a diagonal top view, a perpendicular view and a cross- section, respectively, of a support and guide for a conveyor device according to the invention; Figures 35A-C show a top view of a conveyor device according to the invention and cross-sections of AA and BB of a circulating part of the conveyor device according to the invention, respectively; Figures 36A-E show a detail view of an embodiment of a rigid element according to the invention; Figure 37 shows various modular parts of the guide of the conveyor device according to the invention.

Figure 1 shows a conveyor device 1 according to the invention seen diagonally from above. The conveyor device 1 is provided with a conveyance surface for conveying objects situated thereon in conveyance direction A.

The conveyor belt 2 here defines a practically closed conveyance surface.

The conveyor belt 2 is-at least partially-formed by compressible elements 3 and rigid elements 5 or girders. The conveyor device 1 is furthermore provided on both sides with transverse guides 4 and 4', in this case transverse girders 4 and 4', for guiding the conveyor belt 2 of the conveyor device 1 along a conveyance path. In this picture part of the soft and hard elements has been left out for giving a clear view. In operation the soft and

hard elements form a closed circulating path or conveyor belt, such that the compressible elements in the conveyance direction A are pre-biassed by a compression force F that is parallel to the conveyance direction A yet counter to it. The conveyance path is filled with compressible and rigid elements to such an extent that the compressible elements are at least partially compressed.

Figure 2 shows a conveyor device 1 according to the invention of figure 1 in top view. The conveyor device 1 in this case is provided with a rack-and- pinion drive by means of toothed wheels 8 and 9. For the stability of the drive said toothed wheels 8 and 9 are arranged on both sides of the conveyor belt. In the depicted embodiment the conveyor belt 2 is provided with compressible elements 3 alternating with, at least in the conveyance direction, rigid elements 5. Preferably the rigid elements 5 are also rigid in directions from/out of the plane of conveyance. As a result, the rigid elements offer stiffness and bearing capacity to the conveyor belt. In addition the rigid elements preferably are also torsion stiff along the longitudinal axis of the element, that means the direction perpendicular to the conveyance direction and in the plane of conveyance.

In order to be able to drive the conveyor belt 2, the rigid elements 5 are provided with engagement members 11 that are able to cooperate with the drive means, particularly the toothed wheels 8 and 9, to move the conveyor belt in conveyance direction A. The engagement members 11 to that end have an engagement surface onto which the teeth of the toothed wheels 8 and 9 are able to engage and able to exert a force when they rotate in the direction of the indicated arrow. The rigid elements 5 here fulfil several functions. First of all they offer engagement members to the drive.

Furthermore they provide engagement surfaces for guiding. In addition they provide a compression force on the compressible elements.

Figure 3 shows a cross-section of the conveyor device 1 perpendicular to the

conveyance direction A of the conveyor device 1 of figures 1 and 2.

In this figure it can clearly be seen how the rigid elements 5 are provided with a guiding groove 10 parallel to the conveyance surface 2 having conveyor belt width B, in which the transverse girders 4 and 4'run for exerting a force perpendicular to the conveyance surface for guiding the conveyor belt with the compressible elements 3 and the rigid elements 5 along the conveyance path. It is of course also possible to reverse the functionality, that means providing the rigid elements 5 with parts protruding parallel to the conveyance surface and providing the guides 4,4'with a guiding groove. In the figure the longitudinal axis or centre line I of the rigid elements is indicated.

Figure 4 shows an assembly of a rigid element or girder 5 and a compressible element 3. The rigid element 5, as already stated before, preferably is both rigid in the conveyance direction A and perpendicular to it and moreover torsion rigid. The element has plate part 13 and continuations on both sides outside of the edge of the conveyor belt for offering an engagement for driving and guiding. In this embodiment the rigid element 5 is provided with a guiding groove 10 and is provided with an engagement member 11 onto which engagement means are able to exert a force in the conveyance direction A for propelling the conveyor belt of compressible and rigid elements. The rigid elements 5 are furthermore provided with a stop for exerting a compression or propelling force on the compressible elements. In this embodiment the rigid elements 5 are provided for that purpose with an abutment surface 13. The compressible elements 3 are then provided with a surface cooperating with said abutment surface 13, so that a driving force exerted on the rigid elements, particularly the engagement members 11, is transmitted in the conveyance direction A. In many cases the compressible elements will be compressed in the conveyance direction to such an extent that the spacers of consecutive rigid elements touch each other. In that case the driving force is transmitted or exerted by means of these stops 12 that

also serve as spacers. In that case they have a double function. The compressed elements have a width b, a height h and a length 1, and a centre line t. The compressible element 3 shown is substantially block-shaped.

Furthermore the rigid elements are provided with a stop 12, preferably on both sides, which protrude in conveyance direction A or in its opposite direction. The purpose of said stop is to optionally in cooperation with stops 12 of the next rigid elements, limit the degree of compression of the compressible elements.

From this figure and the preceding figures it is clear how the rigid parts or rigid elements 5 jointly keep the compressible elements 3 together. In a preferred embodiment the compressible elements 3 are glued onto the rigid elements 5, optionally only along the upper edge near the conveyance surface 2. As a result a practically closed conveyance surface 2 is realised.

The combination of the rigid elements 5 and the compressible elements 3 is formed such that jointly they result in a level, continuous and practically closed conveyor belt having a closed conveyance surface 2. In this em- bodiment, as can be seen in figure 2, the compressible elements 3 are compressed to such an extent by means of the rigid elements 5, that the side members or stops 12 of the rigid elements almost touch each other. As a result the side members form stops or spacers 12 due to which the compressible elements 5 are not compressed further than is desirable. It can clearly be seen here that the distance of the longitudinal axes I of the compressible elements can change with respect to each other. The angle of said longitudinal axis in particular can change, due to which a bend can be realised.

Figures 5A-5C show a conveyor belt for a conveyor device according to the invention, wherein 5A shows the situation of the conveyor belt 2 in relaxed condition, that means not confined in the conveyor device 1, wherein the

compressible elements 3 are in a non-compressed condition. Again compressible elements 3 alternating with rigid elements 5 are incorporated in the conveyor belt 2. The longitudinal axes I here have a mutual distance S and are substantially parallel.

Figure 5B shows the conveyor belt 2 of figure 5A in pre-biassed condition, wherein the compressible elements 3 are compressed to such an extent that the spacers 12 of the rigid elements touch each other. In the relaxed condition of figure 5A the pitch in this situation is S, that means the distance S between the centre lines or the longitudinal axes I of the rigid elements 5 for instance approximately 17 units, and in compressed condition this pitch S'is reduced to approximately 12-13, for instance 12.6 units. For preventing chinks between the rigid elements 5 and the compressible elements 3, the compressible elements 3 and the rigid elements 5 in this embodiment are glued together at least along the conveyance surface 2.

In figure 5C the situation of the conveyor belt in a bend or curve is shown.

At the inner side of the bend the distance S is smaller than in the outer bend.

The longitudinal axes of the rigid elements 5 one to the other then are at an angle that does not equal 0. Because the compressible elements expand from an elastically compressed condition, the conveyance surface in the bends will only slightly deform. Moreover the objects that are moved will hardly change position on the conveyor belt. By entering a bend from a partially compressed condition, wherein at the outer side of the bend the compression is at least partially undone, hardly any force is exerted on a possible (glue) connection between the compressible and rigid elements. In addition the shape change from a relative point of view is smaller than for instance in case of stretching. The rigid elements moreover offer a supporting rigidity to the con- veyor belt. It is easy to see that torsion can be realised in the conveyor belt.

The rigid elements here offer support, guidance and pre-bias limitation and transmit the driving force. It may even be possible to provide various rigid elements, each having one of these.

The minimum radius of the bend is determined by the outward spring of the compressible elements at the outer side of the bend into their non- compressed condition. The compressed material may even be slightly stretched. However, this is not preferred. Tension may thus be brought onto a possible glue connection, or an opening can be created in the conveyance surface. The spacers 12 prevent that a compressible element is further compressed. It is moreover preferred that the driving force is transmitted via said spacers 12.

The figures 6-10 show various embodiments of the compressible elements 3 in various views in which A each time is a diagonal perspective view, B a top view, C a front view and D a side view.

Figures 6A-D show a compressible element 3 provided with recesses 14, that means holes 14, which extend over the width of the compressible element. Due to these holes 14 the compression force is reduced and moreover weight is reduced. The compressing element in this example is for instance made of a compressible synthetic material. This may be a solid material or a foamed synthetic material.

Figures 7A-7D show various views of a solid compressible element 3. In this solid embodiment the compressible element 3 preferably is made of a soft, springy, foamed synthetic material. A solid synthetic material that is resilient can also be opted for. A soft springy foamed synthetic material however is preferred, wherein the surface is composed such that in compressed condition and in cooperation with various similar elements it results in an as level as possible conveyance surface 2.

The compressible elements in this case are substantially beam-shaped, and extend over almost the full width B of the conveyor belt. Here they also extend over nearly the full thickness of the conveyor belt. Preferably a

compressible foamed synthetic material is chosen, which, when compressed in one direction, does not or hardly deforms in the directions perpendicular to the direction of the compressing force. Particularly a compressible element is compressed here in the conveyance direction A, and in the process hardly, if at all, transforms the conveyance surface.

Figures 8A-8D show an embodiment of a compressible element 3, here designed laminated with compressible layers 16 alternating with rigid layers 15. As a result a compressible element 3 is created that is compressible substantially only along the conveyance direction and which is able to offer a certain torsion rigidity and supporting rigidity.

Figures 9A-D and 1 OA-D show particular embodiments of rigid and compressible elements. In figures 9A-D the compressible elements are composed of leaf springs. Said leaf springs may be formed as one part from a leaf spring sheet. The leaf spring elements are arranged between the rigid elements 5. It is even possible to form the rigid elements 5 and the compressible elements 3 as one unity.

Figures 1 OA-D show an assembly of compressible elements 3 and rigid elements 5, wherein the compressible elements 3 consist of spiral springs 3 which with their longitudinal axis are arranged perpendicular to the compressible elements and parallel to the conveyance direction A. Just like in figures 9A-D it is possible to design the rigid elements and the compressible elements in this way as one unity.

Figures 11-27 show various embodiments of the rigid elements 5. Said rigid elements are each suitable for an own manner of driving and each have their own field of utilisation. Some of the rigid elements shown, have been developed to be easily produced, and a number of the embodiments have been developed to offer an optimal stiffness or optimal engagement surface for driving. The rigid elements may be of metal such as steel or aluminium or

the like. If so desired it is also possible to produce the rigid elements of synthetic material, fibre-reinforced synthetic material or the like. An ad- vantage of such synthetic materials is that the rigid elements 5 can easily and cheaply be produced in large numbers using for instance an injection moulding process. Moreover the stiffness in various directions is more easily designed and set, which is a particular advantage of this use. In addition the resulting conveyor belt 2 is lightweight.

In the figures 11-27 the rigid elements are each time provided with a stop surface 13 for the compressible elements, spacers 12 for adjusting the degree of compression of the compressible elements, engagement members 11 on either side of the rigid elements, onto which engagement means are able to engage in order to exert a force on the rigid elements in the conveyance direction A, and stops 19 onto which guides are able to engage to guide the conveyor belt along the conveyance path.

In figure 12 the rigid element is provided with holes 18 to reduce weight.

The engagement members 11 in this case are flat ends onto which for instance a friction drive is able to engage or as is later explained, for instance a magnetic drive or otherwise a drive that is able to exert a force on the surface.

The guide means for guiding the conveyor belt along a conveyance path is in this case designed for instance by a lower guide and upper guide that engage onto the surfaces 19.

In figure 13 a rigid element is shown provided with engagement means 11 for for instance a sprocket drive 11 that will be further explained below in figure 29 and 33.

Figures 14A-D, 15A-D, 16A-D, 17A-D show an embodiment of the rigid elements that are easy to manufacture from a flat plate section. In this case

the ends are turned for forming spacers 12 the engagement members 11 for the drive and the guide members, for instance guiding grooves 10. An advantage of these embodiments of the rigid elements is that they can easily be mass-produced.

Figure 18 shows a very simple embodiment of a rigid element provided with a stop surface or abutment surface 13 for the compressible elements, and a practically block-shaped end provided with guide surfaces 19 for guiding and keeping the rigid elements, spacers surfaces 12 and surfaces 11 onto which the drive means are able to engage, along a conveyance path.

In figure 19 a rigid element is shown like in figure 18, however this time provided with a conveyance surface forming part 2, which in the conveyance direction extends perpendicular to the abutment surface 13 for forming a rigid and practically closed conveyance surface. When said conveyance surface 2 is made of a metal or heat resistant or scratch free synthetic material, this rigid element is preferred in conveyor devices used with for instance hot or scratching or possibly conveyor damaging products. The conveyance surface in this embodiment extends at one side of the conveyance surface of the rigid element and in connection with several rigid elements form a closed surface. It is of course also possible to let the conveyance surface extend to both sides to such an extent that they abut each other when the spacers 12 of consecutive rigid elements touch each other.

Figure 21 shows an embodiment of a rigid element wherein the drive substantially corresponds to the one shown in the preceding figures 5, wherein this time however the spacers 12 and engagement members 11 extend to one side only.

Figure 22 shows a rigid element, corresponding to figure 21, here provided with guide surfaces 19 for guiding.

The distance of the rigid elements 5, which are also used in the conveyor belt as shown in among others figures 5A and 5B, is shown in more detail and views in figure 23. In this embodiment the engagement members 11 are toothed wheel cams.

Figure 24 shows a rigid element like figure 23, however, this time not provided with a guiding groove. In this embodiment for instance the surfaces 19 may serve as engagement for the guide means.

Figure 25 shows a rigid element 5, this time provided with a conveyance surface forming part as also described in figure 19, wherein the conveyance surface part extends on both sides of the rigid element.

In figure 26 a rigid element 5 is shown provided with extra protruding members 18 that form extra stop surfaces for a next rigid element. If so desired these members of consecutive elements may be shaped such that, when the rigid elements are used consecutively in a conveyor belt, they partially fall into each other due to which additional stiffness of the conveyor belt is realised.

Figure 27 shows a rigid element provided with engagement members 11 that form toothed wheel cams which can be engaged for driving the conveyor belt from either the upper side of the conveyor belt or from the lower side of the conveyor belt.

Figures 28-33 show various possibilities of driving the conveyor belt according to the invention.

Figure 28A shows a perspective view and figure 28B shows a top view of a conveyor belt having a gear-wheel drive, wherein the toothed wheels are situated parallel to the plane of conveyance. In figure 28A a part of the rigid

and compressible elements have been left out for the sake of clarity. The toothed wheels 8 and 9 engage onto the engagement members 11 which here form toothed wheel cams.

Figure 29A shows a perspective view, 29B a top view, 29C a front view and 29D a side view of a conveyor belt driven by means of toothed wheels which if so desired are placed at the upper side or at the lower side of the conveyor belt.

When the toothed wheels 8 and 9 are placed at the lower side of the belt, said toothed wheels may for instance be mutually connected by means of a rigid shaft, so that drive on both sides is practically simultaneous. In this case the toothed wheels 8 at the upper side of the belt may for instance also be connected through to the toothed wheels 9 at the lower side for realising an even more stable drive, or be free-running for stabilising the drive. For each drive depicted in figures 29A-D for instance the rigid elements shown in figures 17A-27D are suitable.

Figures 30A-D show a drive of the conveyor belt by means of friction bevel gears 30 and 31 on either side of the conveyor belt. The friction bevel gears here are provided with grooves so that they are able to rotate unimpeded by the side guide 4 and 4'.

Figures 31A-31C show a perspective view (31 A), a top view (31B) and a front view (31 C), respectively, of a conveyor device according to the invention provided with a synchronous-belt drive. For such a drive for instance the rigid elements as shown in figures 14,15 are most suitable. An advantage of this drive is that it engages over a longer path so that a more even drive can occur.

Figure 32 shows a drive of the conveyor device by means of for instance magnetic drive. To that end for instance the rigid elements 5 may at the

surfaces (see for instance figure 18, the surfaces 11) be provided with magnets wherein the connecting axis of the north and south poles of the magnets are for instance oriented parallel to the conveyance direction. In this drive the drive elements 33 and 34 for instance provide a changing magnetic field along the conveyance direction, as a result of which the rigid elements are subjected to a force in the direction of the conveyance direction. As a result an almost friction-free drive can be realised which is able to take place in a highly stable manner as a result of which little disruption of the course of the conveyor belt occurs.

Figures 33A-33D show views of a sprocket drive wherein sprocket wheels 35,36 are placed at the lower side of the conveyor belt. Said sprocket wheels 35,36 engage onto the engagement members 11. Rigid elements as for instance shown in figure 13 are suitable for this. In the manner shown in figures 33A-33D it is possible to for instance let the drive take place entirely under the conveyor belt. Optionally it is possible to mutually connect the sprocket wheels 35 and 36 by means of a rigid rod as a result of which an even drive of the belt is possible. It is also possible to provide each sprocket wheel 35,36 with a separate electro motor, and to connect said electro motors one to the other by means of a regulating unit for stably driving the conveyor belt. The engagement members of the rigid elements 5 here run in grooves 4,4'of the conveyor device.

Figure 34A-34D show views of a part of a guide of a conveyor device according to the invention. Said guide is provided with a bottom plate 6 by means of which a closed or practically closed lower side can be realised. The side guides 4,4'depicted here are suitable for guiding rigid elements as depicted in for instance figures 11, 12,14, 15,16, 17,18, 19 etcetera. By means of such a support element provided with guide members 4 and 4'a practically closed conveyor device can be realised.

Figures 35A-C show an embodiment of a return section of a conveyor device

according to the invention. Because of the conveyor belt consisting of compressible elements 3 alternated with rigid elements 5, the circulation shown about a horizontal axis R is easy to realise. The guides 4,4'define the path of the conveyor belt. With the conveyor belt according to the invention a circulation can even be realised about an axis that is at an angle to a horizontal line. Due to its nature the conveyor belt can also run upwards or downwards to for instance another level and further continue horizontally.

When use is made of the return section shown or a similar one, a conveyor device can be realised which for instance makes a single squared bend.

Figures 36A-36E show various views of a rigid element 5 of figure 4 in more detail. Figures 36A and 36B here show a complete image to indicate the detail views.

Figure 36C shows a top view in detail of engagement member 11, wherein the engagement surfaces 11 are indicated onto which a drive engages and is able to exert a pushing force. The spacers 12 are also shown in detail. In general, in parts of the conveyor belt that go straight on, consecutive rigid elements 5 will touch each other near the surfaces indicated with 12 when the conveyor belt is operative. As a result the degree of pushing in or compression of the compressible elements will be limited, due to which the conveyance surface will be almost level and closed. In bends, at the end of the rigid elements that runs at the outside, room will be created between these surfaces to cater for the difference in length of the conveyor belt between the inner bend and the outer bend. The compressible elements are then able to expand so that a closed surface is maintained. Moreover, in case of a right choice of compressible synthetic material, the conveyance surface need hardly deform, if at all.

Figure 36D shows a view P (see figure 36A) of the rigid element. It can clearly be seen here that the groove 10 tapers to the inside at an angle a at both sides. As a result a possible running out of true in the bends is further

prevented. The groove has surfaces 19 that form abutment surfaces for a tongue guide (4,4'is for instance figure 1) as a result of which a force can be exerted on the tongue guides 4,4'to define a conveyance path.

For the sake of clarity a cross-section along line AA of figure 36D is also shown.

Figure 37 shows a top view of a possible embodiment of a conveyor device having a conveyance path having several bends. Here the framework with guides 4,4'is built up from elements 37-40, with frame parts 40 straight path sections, frame parts 37 180 path sections, frame part 39 an 90 path section and frame parts 38 45 path sections. These standardised elements together make it possible to realise almost every conveyance path. The invention to that end regards an assembly of frame parts, provided with a guide and with connection parts to connect several frame parts into a conveyance path wherein the guides run along the conveyance path.

It will be clear that the above description is made to illustrate the operation of preferred embodiments of the invention, and not to limit the scope of the invention. The scope of the invention will only be limited by the following claims. Starting from the above elucidation many variations that fall within the spirit and the scope of the present invention will be evident to an expert.