EP3308915B1 - Method and device for cutting open food products and method for detecting the beginning of a food product - Google Patents

Description

The present invention relates to a device for slicing food products, in particular high-performance slicers, according to the preamble of claim 1 with a product feed that feeds at least one product to be sliced to a cutting knife rotating and / or revolving in a cutting plane, the product feed being a feed device and a feed device comprises downstream driven conveyor belt, which is adjustable between a locking position serving as a product stop in a start phase and a release position serving as a product conveyor in a cutting phase following the start phase.

A device with the features of the preamble of claim 1 is from DE 10 2015 015 166 A1 known.

The invention also relates to a method for recognizing the beginning of the product by a processing device along a conveyor line for food products. The start of the product can be recognized in a start phase of a method for slicing food products, in particular carried out by a high-performance slicer, in which at least one product to be sliced is fed to a cutting knife rotating and / or revolving in a cutting plane by means of a product feed, the product feed comprising a feed device and the conveyor belt comprises a driven conveyor belt arranged downstream of the feed device.

In the prior art, belts are generally used as a support surface for the products to feed products to a knife of a slicing machine. For example, single-track belt drives are known, which extend over the entire width of the support surface, with the product advancement then being carried out on a track-by-track basis in the case of several parallel tracks in the cutting mode by means of product grippers which grasp the rear end of the product. One then accepts a little slippage between the underside of the product and the support surface when grippers that can be operated independently for each track or drive or conveyor belts that act on the product from above, also known as tractor belts, determine the product advance.

Also known are gripper drives arranged laterally next to the product conveyor belt. These consist, for example, of at least one guide and a spindle as a drive for the axial movement of a common gripper holder, which extends over several product lanes. Several product grippers, each assigned to a track, are attached to this holder.

In the case of a multi-lane product feed, the gripper holder thus moves several grippers back and forth at the same time. In addition, each gripper has a so-called vario drive, with which it can also be adjusted over a limited distance independently of the other grippers, on the one hand to compensate for different product lengths on a track-by-lane basis and, on the other hand, to enable reliable gripping of the respective rear end of the product despite these length differences.

An exemplary slicing machine of the type described above comprises a relatively short conveyor belt as a traction device, product support and support directly on the knife or on the feed side directly in front of - seen in the feed direction - the cutting edge.

Basically known is the pivoting of such a conveyor belt, for example by 90 ° with respect to the feed direction into a blocking position, so that it can serve as a stop for the products during the loading phase. After loading, the conveyor belt swings back into a conveying or release position. In this regard, reference is made again to the one already mentioned at the beginning DE 10 2015 015 166 A1 referenced.

For an optimal multi-lane cutting process, it is now important that all of the products are actually in contact with the product stop with their front ends, so that a clear reference position of the products is given. If, for example, the products are scanned in the feed or loading area and the machine control system creates a cutting plan which, among other things, brings unusable end areas, a desired slice thickness and a target portion weight into line with the respective existing product length, the positions of the scanned products relative to the cutting plane must be known be. For this purpose is mentioned in the above DE 10 2015 015 166 A1 nothing mentioned.

It is an object of the invention to create the simplest and most reliable possible way of recognizing the beginning of the product while at the same time ensuring short loading times, reliable gripper travel control and precise gripper positioning.

The object of the invention is achieved by the subject matter of claim 1, and in particular in that a control device is provided, which is designed to detect the product start of a product moved in the start phase by means of the feed device, the application of the product start to the driven in the blocking position Detect conveyor belt by monitoring a drive of the conveyor belt.

The start phase is to be understood here as a period in which no product is sliced, but rather certain preparatory processes take place, in particular loading the slicing device with one or more products, conveying the products in the conveying direction, aligning the front product ends, grasping the rear product ends, as well as feeding the products up to just before the cutting level or up to the cutting level. The start phase can include one or more of these processes.

The invention represents a particularly simple and yet precise solution for recognizing the beginning of the product. In particular, no additional sensors, such as light barriers, are necessary for initial recognition. The device can consequently be implemented in a particularly cost-effective manner.

In one embodiment, the drive of the conveyor belt comprises an electric motor and the control device is designed to monitor a parameter of the power supply of the electric motor and to detect a change in the parameter caused by engagement, contact and / or touching of the beginning of the product with the conveyor belt. The engagement of the beginning of the product with the conveyor belt can, for example, act as a resistance on the conveyor belt, so that it can be recognized on the electric motor or the control device that, for example, a larger current is necessary in order to maintain a setpoint speed. Alternatively, for example, only a reduction in the rotational speed or speed of the conveyor belt can be detected.

In general, according to the invention, a so-called tracking error can be recognized and evaluated, that is to say a deviation between a setpoint value and an actual value.

In a further embodiment, the parameter is the power consumption of the electric motor and the control device is designed to provide a predetermined one or to detect an increase in power consumption that exceeds a predefinable threshold.

In particular, it is provided that the threshold is a current consumption value which is above a reference value which is determined within a predeterminable or predefined period of time before the start of the product is applied to the conveyor belt in the blocked position, in particular within a period of time shortly before, during or begins after moving the conveyor belt into the blocking position and in which the conveyor belt is driven.

As a result, the current consumption when the conveyor belt is running, in the blocked position, can be used as a reference value, in order to take into account the current operating situation immediately before the start of the product comes into contact with the conveyor belt.

It is preferably provided that the conveyor belt can be driven against the conveying direction in the starting phase, in particular at least in the blocking position and / or at least temporarily. This can reliably prevent the product from being moved out of a desired position by the conveyor belt. The conveyor belt does not need to be driven against the conveying direction during the entire start phase. It is sufficient if this only takes place, for example, when the conveyor belt is in the blocked position, or if this takes place during a period of time in which the front end of the product is expected on the conveyor belt in the blocked position.

In a further development, the conveyor belt is arranged in the region of the cutting plane and / or directly in front of a cutting edge that interacts with the cutting knife.

The conveyor belt can serve as a product support during the cutting phase.

The conveyor belt is preferably pivotable between the blocking position and the release position.

In a further embodiment, at least the conveyor belt is multi-lane and comprises several independent belt sections, for which the application of a respective product start can be recognized independently of one another.

The object of the invention is also achieved by a method according to claim 9. In this case, a conveyor belt that can be adjusted between a blocking position serving as a product stop and a release position serving as a product conveyor is provided in particular in the conveying path. In the process, the conveyor belt is adjusted and driven into the blocking position, the product is moved against the driven conveyor belt which is in the blocking position and the start of the product on the driven conveyor belt is detected by monitoring a drive of the conveyor belt.

As already mentioned at the outset, the start of the product can be recognized in a start phase of a method for slicing food products, in particular carried out by a high-performance slicer, according to the dependent claim 10. In a cutting phase following the start phase, with the conveyor belt moved into a release position serving as a product conveyor, the product is fed to the cutting plane and cut open by means of the cutting knife.

In addition, the method according to the invention can advantageously be further developed by the embodiments described below. The device described can also be developed further in the sense of these embodiments. Conversely, the method described herein can also be used in the sense of the herein in Advantageously develop the embodiments described in connection with a device.

One embodiment of the invention is characterized in that the drive of the conveyor belt comprises an electric motor and a parameter of the power supply of the electric motor is monitored, a change in the parameter caused by the engagement of the product start with the conveyor belt being evaluated as the product start being applied to the conveyor belt.

In this case, for example, an increase in the power consumption of the electric motor that exceeds a predefined or predefinable threshold can be assessed as a concern for the beginning of the product on the conveyor belt.

As already mentioned above, the current consumption when the conveyor belt is running in the locked position is preferably used as a reference value in order to detect the current operating situation immediately before the start of the product touches the conveyor belt.

In a further development, the conveyor belt is driven against the conveying direction in the starting phase.

The conveying speed of the conveyor belt can advantageously be selected in the starting phase as a function of at least one product property.

In a further embodiment, the drive of the conveyor belt is stopped as soon as the start of the product is detected.

In yet another embodiment, the product feed takes place in multiple lanes and the product start detection is carried out in the lanes independently of one another.

The start of a product is detected, for example, by monitoring the motor current of an electrical drive assigned to at least one conveyor track for a product. As soon as a product touches the conveyor belt, for example the mechanical resistance (or belt running resistance) and in particular the motor current of the respectively assigned track drive increases proportionally. For this purpose, a current recording can be made, whereby, for example, a significant change can be determined when the product comes into contact. In order to save time, for example, when the conveyor belt is swiveled up, it can be driven in idle mode and the current recording activated. This means, for example, that the current motor current can always be recorded and external influences (e.g. increased resistance due to relatively high belt tension, wear, etc.) can be masked out.

A threshold value for the motor current, which must be reached, for example, for product identification, can be specified. The threshold value can flow into a regulation or control system as an offset value and can be set before or during the, in particular each, detection process (or loading process) in relation to the previously detected motor current during idling.

The conveyor belt can, for example, be drivable backwards so that the strand of the conveyor belt near the end piece runs towards the support surface. This tends to result in the front end of the product being pressed down or held down on the support surface, i.e. in a stable position. Alternatively, the conveyor belt can also run forwards.

A motor speed for product detection in a starting phase or loading position can be predeterminable. The belt speed of the conveyor belt is preferably as slow as possible (for example to protect the product). In particular, the belt speed hardly deviates from a normal conveying speed away. For example, the belt speed can also be adjustable as a function of product properties (for example consistency) and / or as a function of a belt surface used (for example adhesive properties).

The conveyor belt can be driven continuously to detect the beginning of the product, i.e. the control for the electric drive tries to maintain a specified motor speed. If the mechanical resistance increases due to the contact of the conveyor belt with the at least one product, the power consumption of the drive motor can increase, for example.

A plurality of products, in particular products to be cut open in parallel, can also be provided in the product feed. In particular, a dedicated track and / or a dedicated conveyor belt and / or one or more dedicated belt drives can be provided for each product. In particular, a track-specific driving and monitoring of the motor current of a respective belt drive for product start detection can be provided. In this way, even with several conveyor belts, the product contact with the product stop and the reaching of the correct position can be detected on a track-related basis by a motor current that increases suddenly, in particular.

The conveyor belt can, for example, be stopped as soon as the beginning of the product is recognized. This can be done, for example, to protect the starting area of the product, so that little or no abrasion occurs.

In particular, when a product does not lie against the product stop and no product start is detected in a predeterminable time window for the product start detection, the product can be advanced further, for example by moving a gripper holder further. This can take place, for example, after gripping (then possibly too early), but also - for example, depending on the respective design of the product gripper - before gripping.

It is optionally possible for further active feed elements to be activated as a function of the product start detection. This includes, for example, guide elements, such as (lateral) dividers between several tracks, which remain relaxed in the start or loading phase until the product is detected, in order to offer as little resistance or adhesion surface for a product as possible. A conveyor belt on a so-called loading rocker, which serves as a product support surface, can also be driven depending on the product start detection and, for example, if the product start is not recognized, it can start again to push the product forward.

As an alternative or in addition to the measures mentioned above, the contact of the beginning of the product on the conveyor belt can also be detected by recording and evaluating bearing forces, vibrations and / or noises.

The above-described methods and devices according to the invention and their embodiments have particular advantages, which are given below by way of example. For example, a particularly reliable product start detection for reaching an initial position before starting a slicing operation is achieved. A further advantage consists in particularly short, optimized loading times and, in connection with this, particularly good gripper travel control and gripper positioning. In particular, product grippers can move relatively quickly and relatively close to a product end. Furthermore, in the invention, the product recognition function is integrated in components that are already present, in particular in the electric drive for the conveyor belt or in its control. No additional sensors are necessary, which can be prone to errors, such as photoelectric barriers that tend to get dirty. Loading errors and corresponding error messages are also avoided. Another benefit are the Reduction of incorrectly weighted portions and an increase in the yield when slicing.

Fig. 1

zeigt eine erfindungsgemäße Vorrichtung zum Aufschneiden von Lebensmittelprodukten.

Fig. 2

zeigt eine Förderstrecke für Lebensmittelprodukte, die das erfindungsgemäße Verfahren zur Produktanfangserkennung nutzt.

Fig. 3, 4 und 5

zeigen weitere erfindungsgemäße Ausführungsformen.

The invention is explained below by way of example only with reference to the schematic drawing.

Fig. 1

shows a device according to the invention for slicing food products.

Fig. 2

shows a conveyor line for food products that uses the method according to the invention for product start detection.

Figures 3, 4 and 5

show further embodiments according to the invention.

In Fig. 1 a device 10 designed as a high-performance slicer for slicing food products is shown. The device 10 comprises a product supply for supplying a product 12 to a cutting knife, not shown, which works in a cutting plane 14. The product feed comprises a feed device which, in the present embodiment, comprises a product support 18 and a gripper 16, also referred to as a product holder, which is movable along a feed direction for feeding the product 12. The product support 18 can, for example, be designed as a freely running belt or also as a sliding surface, or else it can also drive the product 12 in the feed direction.

A conveyor belt 20 is arranged in the feed direction between the feed device and the cutting plane 14. A cutting edge 26 is also provided between the conveyor belt 20 and the cutting plane 26. The conveyor belt 20 comprises two deflection rollers 30, 32 and is closer to the axis of rotation of the feed device Deflection roller 32 pivotable. The conveyor belt 20 is shown in a release position in solid lines. In contrast, the conveyor belt 20 'is shown in broken lines in a blocking position. The conveyor belt 20 can be pivoted here by approximately 90 ° between the release position and the blocking position, although a different angle can also be provided between these two positions.

A drive 24 is provided for the conveyor belt 20 and is controlled via a control 22 which also controls the gripper 16. In the release position, the conveyor belt 20 is driven in a conveying direction F for feeding the product 12 to the cutting plane 14. In the blocked position of the conveyor belt 20 ', however, it is driven in a direction of detection D in a direction of rotation that is opposite to the direction of rotation of the conveying direction F.

If, in the blocked position of the conveyor belt 20 ', the product 12 is moved towards the conveyor belt 20' by the gripper 16 and finally touches it, there is an increased running resistance in the conveyor belt 20 'compared to idling. This increased running resistance manifests itself in a higher load or a higher necessary current consumption in an electric motor of the drive 24. This increased load or current consumption is recognized by the controller 22 and evaluated as recognition of an engagement of the product 12 with the conveyor belt 20 '. As a result, the beginning of a product can be detected precisely and with simple means, in particular with components that are already present.

The pivot axis of the conveyor belt 20 can coincide with the axis of rotation of the deflection roller 32, as shown in FIG Fig. 1 is shown. Alternatively, the conveyor belt 20 can be pivoted about the axis of rotation of the other deflection roller 30 or about a pivot axis which lies approximately in a central belt area between the two deflection rollers 30, 32. Such a central pivot axis can be formed, for example, by a suspension or support structure of the conveyor belt 20. Even in the embodiments described below, the position of the pivot axis of the conveyor belt 20 can be varied.

In Fig. 2 a conveyor line 110 for conveying a food product 112 is shown. The conveyor line 110 comprises three conveyor belts 118, 120 and 128 for conveying the product 112, in Fig. 2 from right to left.

While the conveyor belts 118 and 128 are designed as conventional powered conveyor belts, the conveyor belt 120 is similar to the conveyor belt 20 of FIG Fig. 1 executed, namely with a pivoting function and with a product interference detection. Drives and a controller according to the embodiment of Fig. 1 are provided, but for the sake of simplicity in Fig. 2 not shown.

Also in Fig. 2 the conveyor belt 120 is shown in a release position in solid lines and indicated in a blocked position in dashed lines 120 '. The conveyor belt 120 'in the blocked position serves as a product stop. When the product 12 comes into contact with the conveyor belt 120 ′, according to the description, FIG Fig. 1 the intervention of the product is detected. In this way, independently of special equipment such as a slicer, for example Fig. 1 A product start detection can be carried out precisely and with simple means in a mere conveyor line 110. Depending on the specific design of the overall system, it can also be important for its operation along a conveyor line to reliably and reliably detect the front ends of the conveyed products.

Also in the Figures 3 to 5 For the sake of simplicity, components such as drives and controls have been omitted.

In the variant according to Fig. 3 the conveyor belt 20 is compared to the variants according to FIG Fig. 1 and 2 opposite and pivoted through a smaller angle. The beginning of the product is detected in the area of the deflecting roller 32. The conveyor belt 20 is erected, for example, until the deflecting roller 32 reaches a height level which corresponds approximately to the expected product center or the height level of the front product end.

In the variant of the Fig. 4 the conveyor belt 20 comprises three deflection rollers 30, 32. In the blocked position shown here with solid lines with the conveyor belt 20 pivoted up, the front product end rests against an intermediate area of the conveyor belt 20 between the two deflection rollers 32. Any flexibility of the revolving belt that may be present can prove to be advantageous here. In the pivoted down release position, which is shown in dashed lines, the conveyor belt 20 serves as a product conveyor.

In the variant of the Fig. 5 In addition to a lower conveyor belt 21, an upper conveyor belt 20 is provided, which can also be referred to as a traction belt, guide belt, holding belt or feeler belt and serves to detect the beginning of the product in accordance with the conveyor belts 20 explained with reference to the above variants. In addition, the lower conveyor belt 21, for example according to the variant of FIG Fig. 3 be pivotable into a blocking position in order to offer an additional detection option.

In general, according to the invention, the conveyor belt adjustable between the blocking position and the release position is not only to be understood as a conveyor belt on which the product rests while it is being conveyed and which conveys the product on its own. Rather, conveyor belts that support product conveyance in whatever way - as in the variant according to FIG Fig. 5 shown - can also be arranged above the products to be conveyed, product conveyors within the meaning of the invention.

List of reference symbols

10

contraption

12th

product

14th

Cutting plane

16

Grapple

18th

Edition

20, 20 '

Conveyor belt

21

Conveyor belt

22nd

Control device

24

drive

26th

Cutting edge

30th

Pulley

32

Pulley

110

Conveyor line

112

product

118

Conveyor belt

120, 120 '

Conveyor belt

128

Conveyor belt

F.

Conveying direction

D.

Detection direction

Claims (15)

1. An apparatus (10) for slicing food products, in particular a high-performance slicer,
   comprising a product feed which feeds at least one product (12) to be sliced to a cutting blade rotating and/or revolving in a cutting plane (14),
   wherein the product feed comprises a feed device (16, 18) and a driven conveyor belt (20) which is arranged downstream of the feed device and which is adjustable between a blocked position serving as a product abutment in a start phase and a release position serving as a product conveyor in a cutting phase following the start phase,
   characterized in that
   a control device (22) is provided which, in order to recognize the product start (12) of a product moved in the start phase by means of the feed device (16, 18), is configured to recognize the contact of the product start with the conveyor belt (20), which is driven in the blocked position, by monitoring a drive (24) of the conveyor belt (20).
2. An apparatus (10) in accordance with claim 1,
   characterized in that
   the drive (24) of the conveyor belt (20) comprises an electric motor and the control device (22) is configured to monitor a parameter of the power supply of the electric motor and to recognize a change of the parameter caused by the engagement of the product start with the conveyor belt (20).
3. An apparatus in accordance with claim 2,
   characterized in that
   the parameter is the power consumption of the electric motor and the control device (22) is configured to recognize an increase of the power consumption which exceeds a predefined or predefinable threshold.
4. An apparatus in accordance with any one of the preceding claims,
   characterized in that
   the conveyor belt (20) can be driven against the conveying direction (F) in the start phase.
5. An apparatus in accordance with any one of the preceding claims,
   characterized in that
   the conveyor belt (20) is arranged in the region of the cutting plane (14) and/or directly in front of a cutting edge (26) cooperating with the cutting blade.
6. An apparatus in accordance with any one of the preceding claims,
   characterized in that
   the conveyor belt (20) serves as a product support in the cutting phase.
7. An apparatus in accordance with any one of the preceding claims,
   characterized in that
   the conveyor belt (20) is pivotable between the blocked position and the release position.
8. An apparatus in accordance with any one of the preceding claims,
   characterized in that
   at least the conveyor belt (20) is of multi-track design and comprises a plurality of belt sections which are independent of one another and for which the contact of a respective product start can be recognized independently of one another.
9. A method of recognizing the product start of food products (12, 112) fed to a processing device along a conveying path (110),
   wherein a conveyor belt (20, 120) is provided in the conveying path (110), said conveyor belt (20, 120) being adjustable between a blocked position serving as a product abutment and a release position serving as a product conveyor, and in which

   - the conveyor belt (20, 120) is adjusted into and driven in the blocked position,

   - the product (12, 112) is moved against the conveyor belt (20, 120) which is located and driven in the blocked position, and

   - the contact of the product start with the driven conveyor belt (20, 120) is recognized by monitoring a drive (24) of the conveyor belt (20, 120).
10. A method in accordance with claim 9,
    characterized in that
    the product start is recognized in a start phase of a method of slicing food products, in particular carried out by a high-performance slicer (10), in which

    - at least one product (12) to be sliced is fed by means of a product feed to a cutting blade rotating and/or revolving in a cutting plane (14), with the product feed comprising a feed device (16, 18) and the conveyor belt (20) being arranged downstream of the feed device, and

    - the product (12) is fed to the cutting plane (14) and sliced by means of the cutting blade in a cutting phase following the start phase when the conveyor belt (20) is adjusted into a release position serving as a product conveyor.
11. A method in accordance with claim 9 or claim 10,
    characterized in that
    the drive (24) of the conveyor belt (20, 120) comprises an electric motor and a parameter of the power supply of the electric motor is monitored, with a change of the parameter caused by the engagement of the product start with the conveyor belt (20, 120) being evaluated as a contact of the product start with the conveyor belt (20, 120), with in particular an increase of the power consumption of the electric motor that exceeds a predefined or predefinable threshold being evaluated as a contact of the product start with the conveyor belt (20, 120).
12. A method in accordance with claim 11,
    characterized in that
    the threshold is a power consumption value which lies above a reference value which is determined within a predefinable or predefined time period before the contact of the product start with the conveyor belt (20) located in the blocked position, in particular within a time period which begins shortly before, during or after the adjustment of the conveyor belt (20) into the blocked position and in which the conveyor belt (20) is driven.
13. A method in accordance with any one of the claims 10 to 12,
    characterized in that
    the conveyor belt (20, 120) is driven against the conveying direction (F) in the start phase; and/or in that the conveying speed of the conveyor belt (20, 120) is selected in the start phase in dependence on at least one product property.
14. A method in accordance with any one of the claims 9 to 13,
    characterized in that
    the drive (24) of the conveyor belt (20, 120) is stopped as soon as the contact of the product start is recognized.
15. A method in accordance with any one of the claims 9 to 14,
    characterized in that
    the product feed takes place on multiple tracks and the product start recognition in the tracks is carried out independently of one another.

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