The present invention relates to an assembly of a vertical conveyor and a further conveyor, as well as to such a vertical conveyor or further conveyor.

A vertical conveyor developed and offered by the Applicant is the Prorunner MK5. This is a continuous vertical conveyor, which is specifically suitable for average to high capacity applications. It comprises carriers that are moveable in an endless track, wherein said carriers are configured to transport products between a supply conveyor and a discharge conveyor that are arranged a different height levels. The carrier thus picks up products from the supply conveyor and sets the products down on a discharge conveyor, thereby bridging a height difference.

During use, products may sometimes fall off a carrier and get trapped, possibly causing damage to either one of the assembly as a whole, i.e. to the vertical conveyor, the supply conveyor and/or the discharge conveyor, or to the product.

GB 959725 A, which is considered the closest prior art, discloses a paternoster elevator having a safety, relative to which at least the characterizing features of the independent claims are novel. The Japanese patent application JP S6265823 A also discloses a vertical conveyor having a safety. GB 15864 A A.D. 1909 is acknowledged as further prior art.

An objective of the present invention is to provide an assembly, that is improved relative to the prior art and wherein at least one of the above stated problems is obviated.

The invention proposes two alternative solutions, i.e. one of a mechanical nature and an other of an electrical / electronic nature, to the problem of how to prevent damage to either one of the assembly as a whole, i.e. to the vertical conveyor, the supply conveyor and/or the discharge conveyor, or to the product. These alternative solutions are presented as a first aspect and a second aspect respectively, each relating to an independent assembly claim, because these alternatives may be applied fully independently of each other. It is however also conceivable that the mechanical and electrical / electronic solutions are, instead of independently of each other, applied in combination.

Said objective is achieved with the assembly according to a first aspect of the present invention, comprising:

- a vertical conveyor configured to at least one of pick up products from and place products on a transfer section of a further conveyor;

- wherein at least one of the carrier of the vertical conveyor and the transfer section of the further conveyor comprises a safety that is configured to detect a product blocking a carrier of the vertical conveyor and stop the assembly; and - wherein the safety comprises a pivot that is configured to allow a displacement of at least one of the carrier or of the transfer section to mitigate damage to the assembly and/or to the blocking product.

The assembly according to this first aspect of the invention comprises a mechanical safety that comprises a pivot that is configured to allow a displacement of at least one of the carrier or of the transfer section to mitigate damage to the assembly and/or to the blocking product. In this way, the carrier is incorporated as part of safety means used for detecting a product that would block and thereby impede the operation of the assembly, and that would consequently possibly cause damage to said assembly. The mechanical safety according to the first aspect provides a simple, reliable and robust safety.

By stopping the assembly as soon as a product blocking the carrier is detected, unnecessary damage to the assembly and/or to the product may be prevented.

Said objective is also achieved with the assembly according to a second aspect of the present invention, comprising:

- a vertical conveyor configured to at least one of pick up products from and place products on a transfer section of a further conveyor;

- a safety configured to detect a product blocking a carrier of the vertical conveyor and stop the assembly;

- wherein the safety is an electrical or electronic safety that comprises a measurement apparatus associated with a motor of the assembly, a processor configured to monitor movement of or in the assembly, and a motor driver configured to stop the motor when movement of or in the assembly is detected by the processor to have halted or slowed down to an extent indicative of a blockage; and

- wherein the processor and/or motor drive is configured to reverse the motor relative to a movement thereof before the block, stop or slow-down is detected.

The assembly according to this second aspect of the invention comprises an electrical or electronic safety that may be used instead of or in addition to the mechanical safety according to the first aspect described above. By applying a processor and/or motor drive that is configured to reverse the motor relative to a movement thereof before the block, stop or slow-down is detected, the assembly according to the second aspect allows a blocking product to be liberated and thereafter manually removed.

The invention is also related to a vertical conveyor of or for such an assembly, comprising a carrier having a safety configured to detect a product blocking a carrier of the vertical conveyor and stop the assembly. Furthermore, the invention is related to a conveyor of or for such an assembly, comprising a transfer section that comprises a safety configured to detect a product blocking a carrier of the vertical conveyor and stop the assembly.

Preferred embodiments are the subject of the dependent claims.

The various aspects and features described and shown in the specification can be applied, individually, wherever possible. These individual aspects, and in particular the aspects and features described in the attached dependent claims, may be made subject of divisional patent applications.

In the following description preferred embodiments of the present invention are further elucidated with reference to the drawing, in which:

Figure 1 is a perspective view of an assembly according to the invention, comprising a vertical conveyor, a further conveyor and a safety;

Figure 2 is a frontal view demonstrating a first possible blocking situation;

Figure 3 is a frontal view demonstrating a second possible blocking situation;

Figure 4 is a frontal view demonstrating a third possible blocking situation;

Figure 5 is a perspective view of a transfer section of the further conveyor of the assembly of Figure 1 ;

Figure 6 is a detailed frontal view of the transfer section of Figure 5;

Figure 7 is a perspective view of the carrier of the vertical conveyor that comprises the safety;

Figure 8 shows a schematic representation of an embodiment of a motor control; and

Figure 9 is a more detailed representation of a potential embodiment of a processor forming part of the motor control of Figure 8.

The assembly 1 comprises a vertical conveyor 2 configured to at least one of pick up products 3 from and place products 3 on a transfer section 4 of a further conveyor 5, and a safety 6 configured to detect a product 3, 3-b blocking a carrier 7 of the vertical conveyor 2 and stop the assembly 1 (Figure 1). By stopping the assembly 1 as soon as a product 3, 3-b blocking the carrier 7 is detected, unnecessary damage to the assembly 1, and possibly also to the product 3, 3- b, may be prevented.

The carrier 7 may comprise a fork shape, wherein the teeth 8 of the fork shaped carrier 7 are configured to pass through spaces between adjacent rollers 9 of the further conveyor 5, which may be a roller track but is not limited thereto. In this way, the carrier 7 may place a product 3 when the carrier 7 moves downward and passes the transfer section 4 of the further conveyor 5. Conversely, the carrier 7 may pick up a product 3 from the transfer section 4 of the further conveyor 5 if a product 3 is present on said transfer section 4 and the carrier 7 moves upward and passes the transfer section 4.

A product 3, 3-b blocking a carrier 7 of the vertical conveyor 2 may occur in a variety of situations as shown in Figures 2-4.

In a first blocking situation as shown in Figure 2, the carrier 7 carries a product 3 and moves downward to place the product 3 on the transfer section 4. However, a further product 3, 3-b that is still present on the transfer section 4 may be blocking the downward travel of the carrier 7.

In a second blocking situation as shown in Figure 3, the carrier 7 moves upward towards the transfer section 4 of the further conveyor 5 to pick up a product 3. It may occur that the carrier 7 still inadvertently carries a further product 3, 3-b. For example, said further product 3, 3-b may accidentally not have been placed down, or said further product 3, 3-b may even have fallen onto the carrier 7. In all cases, said further product 3, 3-b that is inadvertently carried by carrier 7 will block the carrier 7 when said further product 3, 3-b is trapped between the upward moving carrier 7 and the transfer section 4 of the further conveyor 5.

In order to deal with blocking situations of the first and second type described above and shown in Figures 2 and 3 respectively, the safety 6 may be configured to detect a product 3, 3-b blocking between the carrier 7 of the vertical conveyor 2 and the transfer section 4 of the further conveyor 5.

In a third blocking situation as shown in Figure 4, the carrier 7 may carry a product 3, 3-b that extends sideways beyond the carrier 7 to such an extent that it interferes with a travel path of a further carrier 7’ that travels in an opposite direction as carrier 7. The product 3, 3-b may get trapped between the two approaching carriers 7, 7’.

In order to deal with this third type of blocking situation shown in Figure 4, the safety 6 may be configured to detect a product 3 blocking between the carrier 7 of the vertical conveyor 2 and a further carrier 7’ of the vertical conveyor 2.

Although it is conceivable that the safety 6 comprises contactless sensor, e.g. based on vision, a far more simple, reliable and robust safety 6 may be obtained if the safety is a mechanical safety.

At least one of the carrier 7 of the vertical conveyor 2 and the transfer section 4 of the further conveyor 5 comprises the safety 6.

The safety 6 may comprise a pivot 10 that is configured to allow a displacement of at least one of the carrier 7 or of the transfer section 4 to mitigate damage to the assembly 1 and/or to the blocking product 3, 3-b.

The pivot 10 of the safety 6 may be configured to allow a displacement D _u , D _d around pivot axis P if a blocking causes a force above a predetermined threshold. If the force of the predetermined threshold is set at a level that is higher than a downward gravity force caused by the mass of a product 3, a single safety may be used to detect a blocking in the three types of blocking situations shown in Figures 2-4.

In a more preferred embodiment, the pivot 10 of the safety 6 is configured to only allow an upward displacement D _u . If a downward displacement D _d is prevented by the mechanical nature of the pivot 10, the predetermined threshold may set to a significantly lower value than if the threshold needs to be high enough to at least counteract the weight of the heaviest type of product 3 the carrier 7 should be able to carry. Thus, if the pivot 10 only allows an upward displacement D _u , the safety 6 may be set to a more sensitive setting. The sooner the safety 10 detects a product 3, 3-b blocking the carrier 7 and stops the assembly 1, the less damage to the assembly 1 and/or to the blocking product 3, 3-b is likely to occur. This is a benefit for a pivot 10 of both the transfer section 4 and of the carrier 7. A further advantage of the pivot 10 being configured to only allow an upward displacement D _u is of particular importance to carrier 7, because a too far downward displacement D _d could result in a product 3 sliding and falling off of the carrier 7. Such a falling product 3 may damage, may cause further blocking situations similar to Figure 3, and may possibly even cause unsafe situation for human operators.

If both the carrier 7 of the vertical conveyor 2 and the transfer section 4 of the further conveyor 5 comprise the safety 6, all blocking situations shown in Figures 2-4 may be effectively blocked with pivots 10 that are configured to only allow an upward displacement D _u . After all, in the Figure 2 situation the carrier 7 may displace upwardly, whereas the transfer section 4 of the further conveyor 5 may displace, i.e. pivot, upward in the Figure 3 situation. In the blocking situation of Figure 4, the further carrier 7, which is identical to carrier 7, may displace, i.e. pivot, upward. Thus, in a preferred embodiment, each of the carrier 7 (and possibly further carriers 7’) and the transfer section 4 comprises a pivot 10 that only allows an upward displacement D _u .

A very simple, reliable and robust assembly 1 is obtained if the safety 6 comprises a switch 11. The switch 11 may be configured to stop the assembly 1 by breaking an electrical circuit or providing an electrical signal if the safety 6 detects a product 3, 3-b blocking a carrier 7, 7’ of the vertical conveyor 2.

In Figure 8 a motor control 21 is shown, for controlling a motor 20 having an output shaft 22. Output shaft 22 of motor 20 has a tooth wheel 26 at an end thereof to rotationally propel a drive belt 27, connected to the assembly in any of the foregoing figures. Alternatively, a chain or direct drive may be implemented, instead of belt 27.

Control 21 comprises an encoder 23, which is associated with motor shaft 22. Encoder 23 measures rotation of shaft 22. Preferably, encoder 23 is a high resolution encoder, which may, for example, generate IK pulses for a full 360° rotation, but lower resolution encoders, or other measurement equipment may be employed instead of encoder 23. A measurement signal is provided by encoder 23 to a processor 24, which may be configured to detect, from the measurement signals, whether the device is blocked or excessively loaded, causing slow down or stop of the assembly.

When a block, stop or slow down is detected by processor 24 from measurement signals from encoder 23, it generates appropriate control signals for a motor driver 25, to stop the motor 20.

In a preferred embodiment, processor 24 and/or motor drive 25 is configured to reverse motor 20, wherein the reversal is relative to the movement of said motor 20 before the block, stop or slow-down is detected. Thus, blocking product 3, 3-b may be liberated and thereafter manually removed.

The processor 24 may be formed by a CPU of a computer (not shown), or any appropriately programmed PLC (not shown).

However, in the embodiment of Figure 9, processor 24 is embodied as a hard wired or discrete electronics based configuration, comprising connections 28 for connecting to encoder 23, and connections 29 for connecting to the motor driver 25. A hard wired or discrete electronic configuration may have, as an advantage, of functioning very quickly, without being dependent on software and errors therein and/or delays caused thereby.

Encoder signals on pins 3, 4, of input connections 28 from encoder 23 are adjustable distributed via component block 30 and output via component block 31 through connections 29. A detected movement direction is determined by component block 34 and output on pins 4, 5 for “up” and “down”.

A mono-stable multi-vibrator 32, which may be retriggered, generates output signals on pin 6 for “active” of connections 29, during round going movement. Contrary to the indicated fixed resistance R23 33 therein, the pulse duration should be adjustable, and for this resistance R23 33 may be replaced by a variable resistance, and the pulse is output at pin 7 “pulse” of output connections 29. Check of proper round going movement is activated by a first flip-flop stage 35, after the movement active signal is generated and after allowing a lag time, input on pin 3 of the connections 29. A control signal, indicative of slowing down of blockage of the assembly, is generated by second flip-flop stage 35, if the movement active signal falls away in a state of the processor monitoring the proper round going movement. Since the assembly is meant to stop at specific positions, not all control signals from the second flip-flop stage indicate a blockage or unwanted slow down, and the processor may again be set to a monitoring state through a signal on pin 2 for “reset” of connections 29.

The motor driver 25 and the processor 24 may be combined into a single component or assembly of components. The above described embodiments are intended only to illustrate the invention and not to limit in any way the scope of the invention. Accordingly, it should be understood that where features mentioned in the appended claims are followed by reference signs, such signs are included solely for the purpose of enhancing the intelligibility of the claims and are in no way limiting on the scope of the claims. The scope of the invention is defined solely by the following claims.