DE102022128338A1 - Slicing machine with electrostatic application unit for a wetting agent and method for operating such a machine - Google Patents

Abstract

In order to apply the release agent (T) as far as possible only to the desired wetting surfaces of the disks and/or the caliber (K) and in particular to reduce the amount of particles of the release agent (T) floating freely in the working space, an electrostatic application process is used to apply the release agent (T).

Description

I. Area of application

The invention relates to slicing machines, in particular so-called slicers, with which strands of a slightly compressible product such as sausage or cheese are cut into slices in the food industry.

II. Technical background

Since these strands can be manufactured with a cross-section that retains its shape and dimension over their length, i.e. is essentially constant, they are called product calibers.

Usually, several product calibers arranged parallel to one another on individual tracks are cut open at the same time by the same knife, which moves transversely to the longitudinal direction of the product calibers, cutting off one slice at a time in one pass.

The product calibers are pushed forward by a feed conveyor of a feed unit in the direction of the knife of the cutting unit, usually on a feed conveyor directed diagonally downwards, and are each guided through the product openings of a plate-shaped, so-called cutting frame, at the front end of which the part of the product caliber that protrudes beyond this is separated as a slice by the knife immediately in front of the cutting frame, in slicers usually with a cycle time of no more than 800 ms, i.e. a speed of the knife of at least 50 rpm to about 1200 rpm.

The slices usually fall onto a first conveyor, the so-called portioning belt, as part of a conveyor unit, by means of which the individual separated slices are also collected into shingled or stacked portions on the portioning belt and transported away for further processing.

With such portions, where the slices are at least partially on top of each other, there is the problem that, depending on the material, the slices sometimes stick together so strongly that the customer cannot separate them without additional measures.

Then, as a separation aid when preparing the portion, either a so-called interleaver in the form of a sheet of paper or foil is placed between the individual slices or a liquid or powdered release agent is applied to the contact surface of the slice to the next slice of the portion, i.e. part or the entire main surface of the slice, preferably by spraying.

For other reasons, such as hygiene reasons, it may also be desirable to apply a liquid or powdered wetting agent to at least one of the main surfaces of the panes.

In the following we will only talk about release agents, which should also cover wetting agents for purposes other than the later separation of panes lying on top of one another.

However, problems arise such as contamination of the machine by release agent deposited on various machine parts away from the discs and a high level of air pollution with the spray mist of the release agent.

For this reason, additional measures often have to be taken, such as providing for suction of the release agent that is not deposited on the panes.

III. Description of the invention

a) Technical task

It is therefore the object of the invention to provide a slicing machine, in particular a slicer, which minimizes or avoids these problems and yet has a high process efficiency, as well as a method for operating such a slicing machine.

b) Solution to the task

This object is achieved by the features of claims 1 and 11. Advantageous embodiments emerge from the subclaims.

The basic idea of the invention is, on the one hand, to apply the release agent more precisely to the desired disc wetting surfaces and, on the other hand, to remove freely floating particles or droplets of the release agent from the air thereby and/or by providing specifically selected machine wetting surfaces.

With regard to the procedure for operating a slicing machine such as a slicer, which on the one hand has a dispensing unit for dispensing release agent on the main surface of a future or already produced slice and a dispensing opening which dispenses release agent in the direction of such a main surface, the task is solved by the release agent tel is applied using an electrostatic application process.

For this purpose, the release agent dispensed via the dispensing opening on the one hand and the intended wetting surface on the other hand are usually provided with a different electrical polarity, so that an electrical potential difference is created between them and the negatively charged particles or droplets of the release agent are electrostatically attracted to the positively charged desired wetting surface. This also causes particles or droplets to settle on the desired wetting surface that would have moved past the desired wetting surface without the potential difference and would initially have floated in the work area, worsening the air quality there and then settling on some nearby machine part.

For example, the release agent is electrically negatively charged with at least 10kV of electrical voltage, preferably at least 40kV, before leaving the application opening, while the desired wetting surface is electrically positively charged, usually by simple earthing, i.e. electrically conductive connection with the ground, or vice versa.

In known, non-electrostatically assisted application processes, the movement of the particles or droplets of the release agent from the application opening to the wetting surface is usually achieved by means of a corresponding overpressure with which the release agent is applied from the application opening, i.e. it is usually sprayed out in a cone-shaped spray cone or a fan-shaped spray fan or another shape.

In the case of electrostatically charged particles or droplets, this movement can also be caused exclusively by the electrostatic attraction of the wetting surface, if the distance between the two is not too large and also depending on whether or not additional gravitational influences have to be overcome.

In addition, machine wetting surfaces can also be provided on the machine, which are also electrically charged in the opposite direction to the release agent, in order to capture release agent that has not reached the intended disc wetting surfaces and to remove it from the air.

These can be defined machine wetting surfaces that are electrically insulated from the rest of the machine, which then become heavily soiled and have to be cleaned more often, or they can be connected to a collecting container into which the release agent may drain due to gravity, which can, however, greatly reduce the contamination of the other machine parts and thus the cleaning effort.

The desired wetting surfaces can also be electrostatically charged alternately over time, so that, for example, particularly during reloading of the slicing machine, this time is used to separate free-floating droplets or particles from the air on the machine wetting surfaces.

As a rule, when applying a release agent, the release agent is applied to the knife-side front face of the caliber before the disk is separated, in particular completely, or after the disk has been placed on the discharge unit, the main surface of the disk placed, which is then facing upwards, in particular of the last disk placed, is at least partially wetted with release agent, namely in the area of the contact surface to the next disk to be placed on top.

For the electrostatic application process, in the first case, the caliber is contacted via an electrical contact, which preferably acts as close as possible to the caliber face on the knife side. In order to limit the electrostatic charge to the caliber, for example by grounding, the caliber can be electrically insulated from the inner circumference of the product opening of the cutting frame through which it extends, or the cutting frame can be made entirely of a poorly electrically conductive or non-conductive, i.e. dielectric, material.

If the front surface of the caliber is to be wetted, the release of release agent through the release opening is preferably started before the disc is completely separated from the caliber, in particular during the first third of the separation process or even before the start of the separation process, whereby the third is understood to be the temporal third of the duration of the separation process.

On the other hand, the discharge is preferably continued until the disc is completely separated from the caliber, i.e. is in free fall, preferably even until the disc hits the support surface, such as the discharge belt.

If, in the second case, the top of a disc already placed on the conveyor unit is to be wetted with release agent, which usually only happens if the disc is part a portion of mutually touching disks, the disk or portion must be electrically contacted for electrostatic charging, in particular earthing.

The storage surface, for example the conveyor belt on which the corresponding slice or portion lies, can be used directly as an electrical contact if it is designed to be electrically conductive at least on its outer side towards the slices and is in turn, for example, earthed.

However, since such conveyor belts are usually made of plastic and thus a material that is poorly or non-conductive electrically, the slice or portion lying on them is preferably electrically contacted and charged, in particular grounded, with a separate electrical contact.

In order to avoid competition between intended wetting surfaces - if they are simultaneously electrostatically charged, for example grounded - the machine wetting surfaces should be sufficiently spaced from the disc wetting surfaces, in particular at least one third of the largest extension of a disc, in particular the entire largest extension of a disc.

The machine wetting surfaces serve to deposit free-floating particles or particles and are therefore preferably used to remove the release agent deposited there.

In the case of a liquid release agent, this will partially flow down the upright wetting surfaces of the second type due to gravity, in particular if such a machine wetting surface is heated, so that a collecting container arranged at the lower end of the machine wetting surface may be sufficient to remove the release agent from this machine wetting surface, thus avoiding frequent cleaning intervals.

• - eine Schneideinheit mit einem vorzugsweise rotierenden Messer, meist einem Sichelmesser, dessen Schneidkante am Außenumfang entgegen der Drehrichtung in ihrem Abstand vom Drehpunkt zunimmt,
• - eine Zufuhreinheit, um das wenigstens eine aufzuschneidende Kaliber der Schneideinheit zuzuführen,
• - eine Abförder-Einheit für die Scheiben oder daraus gebildeten Portionen mit wenigstens einem Abförderer,
• - eine Ausbring-Einheit mit wenigstens einer Ausbring-Öffnung, insbesondere einer Sprüh-Öffnung, vorzugsweise pro Spur, zum Aufbringen eines flüssigen oder pulverförmigen Trennmittels auf einer der Hauptflächen der Scheiben, insbesondere deren gegenseitigen Kontaktflächen,
• - eine Steuerung zur Steuerung beweglicher Teile der Aufschneide-Maschine.

A generic slicing machine such as a slicer, usually with multiple lanes, for cutting calibers into slices and storing them in shingles or stacks in portions typically comprises

• - a cutting unit with a preferably rotating knife, usually a sickle knife, the cutting edge of which increases in its distance from the pivot point on the outer circumference against the direction of rotation,
• - a feed unit for feeding the at least one caliber to be cut to the cutting unit,
• - a discharge unit for the slices or portions formed therefrom with at least one discharge conveyor,
• - a dispensing unit with at least one dispensing opening, in particular one spray opening, preferably per track, for applying a liquid or powdery release agent to one of the main surfaces of the discs, in particular their mutual contact surfaces,
• - a control system for controlling moving parts of the slicing machine.

The main surfaces of a disc are the two largest surfaces of the disc, which are usually parallel to each other, in particular the cutting surfaces of the disc, which are considerably larger than the peripheral surface.

In the case of shingled portions, i.e. when the slices of the portion are offset from one another in a row but partially overlap in the direction of the row, two consecutive slices only lie on top of one another with part of their main surfaces, the contact surfaces. In the case of a stacked portion, however, the contact surface is the entire main surface.

The liquid or powdered release agent is applied between the disks of a portion either before the next disk is placed on the upper main surface of the preceding disk and/or before the next disk hits the already completed partial portion on its forward and downward facing main surface, in particular the front face of the caliber, preferably only on the contact surface of the respective main surface.

The discharge unit is usually located in the angle area between the diagonally overhanging front surface of the cutting frame or the cutting plane in which the cutting edge of the knife moves and the discharge unit, in particular its portioning belt.

The dispensing unit is preferably arranged and designed such that the at least one dispensing opening dispenses release agent in the direction of one, in particular only one, main surface of a disc - already existing or still to be produced,

A disc that has yet to be produced is the beginning of the caliber, i.e. its knife-side front surface, which after the disc has been separated will be one of the two main surfaces of the disc.

The terms application unit and application opening are understood to mean any unit or opening by means of which a release agent can be applied, regardless of whether it is a nozzle in the classic sense with a narrowing passage opening and regardless of whether the release agent is applied under pressure or not.

In practice, however, the release agent usually has to be moved towards the disc at a considerable speed, since the time available for applying the release agent is very short.

In such a pressurized application, the release agent - whether liquid or powder - is often finely atomized with the help of compressed air or another pressurized transport medium using a spray nozzle, for which the spray nozzle must be supplied not only with the release agent itself but also with this pressurized transport medium - regardless of the type of transport medium, hereinafter referred to as compressed air, without transport being limited to that - via an appropriate supply line.

According to the invention, the application unit is designed as an electrostatic application unit, which means that the release agent dispensed via the application opening on the one hand and the desired wetting surface to which this release agent is to be applied on the other hand each receive a different electrical charge via an electrical contact, i.e. in one case it is electrically negatively charged, in particular by means of a high-voltage generator, and in the other case it is electrically positively charged, usually by simple earthing.

As is known from electrostatic spray painting, due to the electrical potential difference and the resulting electrostatic attraction, the particles or droplets are attracted to the desired wetting surface, which has an opposite charge, and are deposited on it, so that only a much smaller proportion of particles or droplets remain floating freely in the air and slowly sinking as spray mist.

The fact that a so-called electrostatic wraparound also occurs, whereby particles or droplets that have already flown past the object to be wetted turn around and also settle on the back of the object, in this case the panes, facing away from the application opening, in particular the spray nozzle, is not harmful, since the individual panes are usually in contact with an adjacent pane within a portion with both of their main surfaces and a release agent should be present there.

• In der Regel ist die gewünschte Benetzungsfläche die Hauptfläche oder ein Teil der Hauptfläche einer zukünftig erzeugten oder bereits erzeugten Scheibe, um dort möglichst viel Trennmittel abzulagern und nicht abseits davon abzulagern.

More difficult than in a paint booth, in which the object to be painted is simply suspended and this suspension must be electrically contacted, is the electrical insulation of the electrically active parts, i.e. the pane on the one hand and the machine wetting surface on the other, from the machine environment:

• As a rule, the desired wetting surface is the main surface or part of the main surface of a future or already produced disc in order to deposit as much release agent as possible there and not to deposit it away from it.

In addition to or instead of these slice wetting surfaces, a designated machine wetting surface may be present, which is a defined, limited surface or surface area of the slicing machine that can also be electrostatically charged and discharged with a different polarity to the charge of the release agent.

The purpose here is to ensure that the particles or droplets of the release agent, which are still floating freely in space despite the electrostatic support, do not settle anywhere on the machine and thereby contaminate the entire machine, but rather specifically on the defined and electrically connected machine wetting surfaces that are electrically insulated from the rest of the machine.

For this purpose, the application unit is usually connected to a high-voltage generator, which electrically charges parts of the application unit that come into contact with the release agent, in particular the inner peripheral edge and above all the front peripheral edge around the application opening, with a negative electrical charge of at least 10,000 volts, preferably 40,000 volts, so that all particles or droplets emerging there are strongly electrically negatively charged.

The desired disc wetting surface and/or machine wetting surface, on the other hand, should be electrically positive and is earthed for this purpose and, above all, electrically insulated from the rest of the machine, while the rest of the machine is generally not separately earthed but is only connected to the neutral conductor of the power supply.

This arrangement is easier to implement than its reverse.

• Deshalb besteht eine erste Möglichkeit darin, das Kaliber über den das hintere Ende haltenden Greifer elektrisch zu kontaktieren, der hierfür seinerseits elektrisch aufladbar sein muss, insbesondere geerdet sein muss.

If the direction of application of the release agent from the application opening, or in the case of a spray nozzle, the direction of spray, is directed towards the front face of the caliber, i.e. the disc that has not yet been completely produced, the electrical contact with the caliber can be made in different ways, whereby it must be taken into account that in most cases the conveyor belts, including the feed belt for the calibers, are made of a dielectric material, usually plastic, while the cutting frame, through whose product opening a caliber is passed, is usually made of steel, i.e. an electrically conductive material:

• Therefore, a first possibility is to electrically contact the caliber via the gripper holding the rear end, which in turn must be electrically chargeable and, in particular, must be earthed.

As a rule, the cutting frame is then made of a dielectric material such as plastic or, in the case of a cutting frame made of metal, this is insulated from the caliber passing through it by, for example, the inner peripheral surface of the product opening having a lining made of a dielectric material such as plastic so that the caliber does not come into contact with the cutting frame.

Another solution is to apply another electrical contact to the caliber in a sliding or rolling manner instead of the gripper, in particular its gripper prongs, which is preferably possible close to the cutting end, in particular in the transport direction shortly before the cutting frame, since this makes the path length between the contact point and the front face, which is to be electrically influenced by this, much shorter than when contacting the caliber at the rear end.

In order to establish a secure, intimate electrical contact, a contact wheel can be used instead of a simple sliding contact with a fixed metal contact lug, which rolls along the caliber as it is pushed forwards and is preferably equipped with spikes that penetrate slightly into the caliber.

This also makes it possible to mount such a contact wheel below the upper run of the feed belt or an existing lower product guide and to let its spikes extend through openings in the feed belt or product guide belt - preferably made of dielectric material - into the caliber.

Another possibility is to use the cutting frame itself as an electrical contact to the caliber and to earth it if the cutting frame is made of electrically conductive material, since it is in constant contact with the caliber by resting on the lower peripheral area of the product opening.

However, the cutting frame itself is then also electrostatically charged in the same way and its front side, which faces the release agent dispensing opening, for example, acts as a wetting surface just like the front surface of the caliber, on which the release agent will be deposited just as strongly as on the front surface of the caliber.

A further problem may be a casing of the caliber made of a material that is poorly electrically conductive, which impairs the electrical connection between a contact on the outside of the caliber and the front face of the caliber.

Another possibility is to use the feed belt as an electrical contact to the caliber, which would then have to have at least one electrically conductive outer side towards the caliber, which in turn must be electrically chargeable, in particular must be earthed.

The parts of the machine that are not intended as desired contact surfaces must in any case be electrically insulated from the wetting surfaces, since otherwise the electrostatic charge will be distributed over too large an area and become too weak and/or, above all, the machine wetting surfaces will become too large, which is not desirable for reasons of easy, concentrated cleaning of only the machine wetting surface.

Preferably, the at least one machine wetting surface has a minimum distance from the disk that is to be wetted, in particular at least one third of the greatest extent of a disk, preferably the entire greatest extent of a disk, in order to ensure that even the particles or droplets flying past the disk and its wetting surface at a great distance are still diverted to this disk wetting surface, and only the particles or droplets flying very far away are diverted to the machine wetting surface. For this purpose, the machine wetting surface is arranged in particular outside the spray area, in particular the spray cone of a spray opening.

Since the release agent deposited on the machine wetting surface must be removed from there, the machine should be designed in such a way that this does not have to be done by manual cleaning, but can be done automatically by means of an appropriate cleaning device.

One possibility is to arrange such a machine wetting surface in an upright position and to arrange a collecting container at the bottom for the release agent that runs down this wetting surface due to gravity. The flowing down can be promoted by heating this wetting surface, which prevents the release agent from solidifying or even allows the originally solid release agent to liquefy and/or makes the release agent more fluid.

Such a machine wetting surface can be provided between product openings of the cutting frame, but the distance between them is so small that the electrostatic attraction to the caliber front surfaces on both sides should be sufficient to ensure that hardly any release agent is deposited on the front surface of the cutting frame.

Instead, a frame running around the cutting frame could be installed as a machine wetting surface, which of course must be electrically insulated from the rest of the machine.

It would also be possible to arrange a machine wetting surface between the parallel conveyor belts and/or laterally outside the conveyor unit and/or in the length range between the cutting plane and the end of the portioning belt.

• Entweder über die elektrisch leitfähige Kontaktfläche des Abförder-Bandes zur Scheibe hin, die dann ihrerseits elektrisch beaufschlagbar sein muss, insbesondere geerdet sein muss.

If the disc lying on the discharge unit is to be wetted first, i.e. the discharge direction of the discharge opening is directed towards the upward-facing main surface of the last disc deposited - which is only possible due to gravity, especially without pressurized spraying of the release agent - two options are available for the electrical contact of the disc or the portion in which the disc is located:

• Either via the electrically conductive contact surface of the conveyor belt to the disc, which in turn must be electrically chargeable and in particular must be earthed.

Or the conveyor belt, including the contact surface, consists of a dielectric material and the disc or the portion is electrically charged or grounded by a separate, preferably stationary, electrical contact, be it a simple sliding contact or the contact wheel with spikes described with regard to the contacting of the caliber, the spikes of which can reach the portion, for example from the underside and through the upper run of the conveyor belt.

The construction effort for this is less than when using the conveyor belt as an electrical contact.

Especially when wetting the already deposited panes, application without spraying is considered, in which the release agent trickles or flows down onto the pane over a mostly horizontal edge that is highly electrostatically charged.

In all cases, the multiple discharge units in multi-lane slicing machines can be arranged on a functional bar that runs across the discharge unit and is attached to the base frame of the machine via a holding unit, so that the discharge opening can be brought into the optimal position with the optimal discharge direction to the desired wetting area due to various joints and/or other adjustment options.

In order to be able to operate a disc wetting surface and a machine wetting surface at the same time, it can be useful to make or set the charge difference between the release agent and the disc wetting surface to be greater than that between the machine wetting surface. This makes the disc wetting surface the preferred attachment point for the droplets or particles of the release agent, and only those that are relatively far away from it and are only slightly exposed to the electrostatic influence are attracted to the machine wetting surface.

c) Examples of implementation

• 1a, b: eine Aufschneide-Maschine in Form eines Slicers gemäß dem Stand der Technik in unterschiedlichen perspektivischen Ansichten, mit in die Aufschneide-Stellung hochgeklapptem Zufuhrband,
• 2a, b: die Aufschneide-Maschine der 1a, b in der Seitenansicht mit entfernten Verkleidungsteilen, sodass die verschiedenen Förderbänder besser zu erkennen sind, mit jeweils einer erfindungsgemäßen Aufbring-Vorrichtung, deren Aufbring-Richtungen in verschiedene Richtungen zeige, n
• 3a, b: vereinfachte Prinzipdarstellungen je eines Teilbereichs der 2a, b mit Aufbring-Richtungen gemäß der 3a, b,
• 4: die Situation der 2a, 3a in der Aufsicht,
• 5: die Bauform der Ausbring-Einheit gemäß der 2a, b alleine in einer perspektivischen Darstellung,

Embodiments according to the invention are described in more detail below by way of example. They show:

• 1a , b: a slicing machine in the form of a slicer according to the state of the art in different perspective views, with the feed belt folded up into the slicing position,
• 2a , b: the slicing machine of the 1a , b in side view with the cladding parts removed so that the various conveyor belts can be seen better, each with an application device according to the invention, the application directions of which point in different directions, n
• 3a , b: simplified schematic diagrams of each part of the 2a , b with application directions according to the 3a , b,
• 4 : the situation of 2a , 3a in supervision,
• 5 : the design of the application unit according to the 2a , b alone in a perspective view,

The 1a , 1b show different perspective views of a known, multi-lane slicer 1 for the simultaneous slicing of several product calibers K on one lane SP1 to SP4 next to each other and depositing them in shingled portions P each consisting of several slices S with a general flow direction 10* through the slicer 1 from right to left.

1c shows - without the caliber K inserted - a side view of this slicer 1, omitting covers and other parts that are not relevant to the invention, which, like all other units, are attached to the base frame 2, so that the functional parts, especially the conveyor belts, can be seen better. The longitudinal direction 10 is the feed direction of the calibers K to the cutting unit 7 and thus also the longitudinal direction of the calibers K located in the slicer 1.

It can be seen that the basic structure of a slicer 1 according to the prior art consists in that a cutting unit 7 with a knife 3 rotating about a knife axis 3', here a sickle knife 3, is fed several, in this case four, product calibers K lying next to each other on a feed conveyor 4 transversely to the feed direction 10 with spacers 15 of the feed conveyor 4 in between by this feed unit 20, from the front ends of which the rotating knife 3 with its cutting edge 3a cuts off a slice S in one operation, i.e. almost simultaneously.

For cutting the product caliber K, the feed conveyor 4 is located in the 1a , b and 2a, shown in the side view, with a low-lying cutting-side front end and a high-lying rear end, from which it can be folded down about a pivot axis 20' running in its width direction, the first transverse direction 11, which is located near the cutting unit 7, according to 2 B into an approximately horizontal loading position.

The rear end of each caliber K in the feed unit 20 is - see 1a , b, 2a , b - each held by a gripper 14a - d in a form-fitting manner with the aid of gripper claws 16. These grippers 14a - 14d, which can be activated and deactivated with regard to the position of the gripper claws 16, are attached to a common gripper carriage 13, which can be guided along a gripper guide 18 in the feed direction 10.

• Die vorderen Enden der Kaliber K werden jeweils durch eine sogenannte Produkt-Öffnung 6a - d eines plattenförmigen Schneidrahmens 5 geführt, wobei unmittelbar vor der vorderen, schräg nach unten weisenden Stirnfläche des Schneidrahmens 5 die Schneidebene 3" verläuft, in der das Messer 3 mit seiner Schneidkante 3a rotiert und damit den Überstand der Kaliber K aus der Schneidrahmen 5 als Scheibe S abtrennt, wie besser in der vergrößerten Prinzip Darstellung der 3a, b ersichtlich. Die Schneidebene 3" verläuft lotrecht zum Obertrum des Zuförderers 4 und/oder wird von den beiden Querrichtungen 11, 12 zur Zufuhrrichtung 10 aufgespannt.

In this case, both the feed of the gripper carriage 13 and the feed conveyor 4 can be driven in a controlled manner, whereby the actual feed speed of the calibers K is brought about by a so-called upper and lower product guide 8, 9, which is also driven in a controlled manner and which engages the upper and lower sides of the calibers K to be sliced in their front end areas near the cutting unit 7:

• The front ends of the calibers K are each guided through a so-called product opening 6a - d of a plate-shaped cutting frame 5, with the cutting plane 3" running directly in front of the front, diagonally downward facing face of the cutting frame 5, in which the knife 3 rotates with its cutting edge 3a and thus separates the excess of the calibers K from the cutting frame 5 as a disk S, as can be better seen in the enlarged principle illustration of the 3a , b. The cutting plane 3" runs perpendicular to the upper run of the feed conveyor 4 and/or is spanned by the two transverse directions 11, 12 to the feed direction 10.

The inner circumference of the product openings 6a - d of the cutting edge 3a of the knife 3 serves as a counter cutting edge.

Since both product guides 8, 9 can be driven in a controlled manner, in particular independently of each other and/or possibly separately for each track SP1 to SP4, they determine the - continuous or clocked - feed speed of the calibers K through the cutting frame 5.

The upper product guide 8 is displaceable in the second transverse direction 12 - which runs perpendicular to the surface of the upper run of the feed conveyor 4 - to adapt to the height H of the caliber K in this direction. Furthermore, at least one of the product guides 8, 9 can be designed to pivot about one of its deflection rollers in order to be able to change the direction of the run of its guide belt lying against the caliber K to a limited extent.

Below the feed unit 20 there is usually an approximately horizontally running residue conveyor 21, which begins with its front end below the cutting frame 5 and immediately below or behind the discharge unit 17 and with its upper run thereon - by means of the drive of one of the discharge conveyors 17 against the direction of flow 10 - transports falling residues to the rear.

The slices S, which are positioned at an angle in space during separation, fall onto a discharge unit 17 which begins below the cutting frame 5 and runs in the direction of flow 10* and which in this case consists of several discharge conveyors 17a, b, c arranged one behind the other in the direction of flow 10* with their upper strands approximately flush, of which the first discharge conveyor 17a in the direction of flow 10 can be designed as a portioning belt 17a and/or one can also be designed as a weighing unit.

The slices S can be placed individually and spaced apart from each other in the direction of flow 10* on the discharge unit 17 or, by appropriate control of the portioning belt 17a of the discharge unit 17 - the movement of which, like almost all moving parts, is controlled by the control 1* - shingled (see 3a , b) or form stacked portions P by stepwise forward movement of the portioning belt 17a.

In the side views of the 2a , b, 3a , b additionally shows at least one application unit 22 for applying a release agent T to the discs S, of which at least in the 2a , 3a all spray units 22 are pressurized, i.e. by spraying, the release agent T is applied.

A function bar 23 running in the transverse direction 11, to which one application unit 22 is attached per lane - see 5 - is located in 2 B , 3b in such a pivoting position about the transverse direction 11, which is simultaneously the longitudinal extension 23' of the functional beam 23, that the application units 22 mounted on the functional beam 23 with the application direction 24' of their application opening 24.1, mostly spray nozzles 24.ff, point obliquely backwards and downwards and thus, for example, each spray nozzle 24.1 -24.4 wets the top of each of the last slices S already deposited on the portioning belt 17a with the release agent T when the application unit 24 is activated, as in the top view of the 4 shown.

The function bar 23 is located in 2a , 3a in such a pivoting position about the transverse direction 11 that the application units 22 mounted on the function bar 23, in this case spray units 22, point with the spray direction 24' of their spray nozzles 24 approximately horizontally backwards against the flow direction 10* and are directed against the knife-side front face of the caliber K or K1 protruding from the cutting frame 5, which is sprayed with release agent T before it is separated as a disk S from the knife 3.

The design of the application units 22 as electrostatic application units 22 is described in the 2a to 4 This is expressed by the fact that an electrical contact with a plus or minus sign is shown on each of the elements involved as a correspondingly polarized voltage source with which the corresponding element can be charged electrically positively or negatively, whereby the simplest type of positive charging is electrical earthing, shown using the usual earthing symbol. The electrical negative charging is carried out using a high-voltage generator, which is connected to the minus sign and is not shown for reasons of clarity.

In all 2a to 4 the dispensing unit 22, i.e. a component of the dispensing unit 22 which is in contact with the release agent T before or when it emerges from the dispensing opening 24, is shown as electrically negatively charged, whereas the disk S to be wetted and/or the caliber K are shown as electrically positively charged, in particular as grounded.

So in the 2a , b the entire function bar 23 on which, as a rule, 5 several application units 22 are located next to each other, are shown as electrically negatively chargeable. However, in contrast to the representation of the 5 It could be a single application unit 22 extending across all tracks in the transverse direction 11, which would, however, hinder the adaptation to the number of tracks and track spacing.

In the 2a , b the caliber K or the caliber residue KR is shown as electrically positively charged, in particular through contact with the gripper 14, which is also shown as electrically positively charged and is usually grounded, the electrically conductive gripper tines 16 of which engage electrically conductively in the caliber, whereby the caliber K itself is generally also electrically conductive due to the moisture it contains.

In 3a Deviating from this, the caliber K is electrically positively charged, in this case earthed, by a spiked wheel 25 which is rotatable about an axis running in the transverse direction 11 below the upper run of the lower product guide 9 and which extends with its spikes - which are electrically positively charged, in particular earthed - through openings in the upper run into the caliber K.

As indicated, the downstream, knife-side deflection roller of the lower product guide 8 itself can also be designed as such a, then grounded, spiked roller 25.

In 3a In addition, the cutting frame 5, which in this case consists of an electrically conductive material such as steel, is electrically positively charged, here by earthing, wherein the circumference of the product opening 6 can be electrically insulated from the cutting frame 5 by an insulation 27, especially if the electrical potential of the cutting frame 5 on the one hand and the caliber K on the other hand is to be selected to be different.

If such insulation 27 is not present, both have the same electrical potential and release agent T will be deposited on both the front surface of the caliber K and the knife-side front surface of the cutting frame 5.

In the case of a liquid release agent T, this will run downwards along the cutting frame 5 due to gravity - preferably conveyed by a warmed, heated cutting frame 5 - and drip into a collecting container 26 located there at the lower end, which reduces or completely avoids the effort for manual cleaning of the cutting frame 5.

In 3b In addition to the negative charge of the discharge unit 22, in particular its discharge opening 24, it is shown that the portion P lying on the portioning belt 17a of the discharge unit 17, in particular the last slice S deposited there, is electrically positively charged by earthing, in this case again by means of a spiked wheel 25 which rotates below the upper run of this portioning belt 17a about an axis running in the transverse direction 11 and extends with its spikes through the upper run into the slice S, the stacks being electrically positively charged, in this case being earthed.

Such a pinion 25 is shown in the top view of the 4 shown as an example on the track SP4, via which the disk S and thus also its upwardly facing main surface, which is the intended disk wetting surface 50S, is electrically positively charged.

In the case of track SP3, it is evident that the portioning belt 17a3 itself is electrically positively charged in this track, for example, it is grounded, for which it must of course have at least one electrically conductive upper side towards the disks S, which can be electrically positively charged.

In all tracks, the release agent T emerging from the application units 22 is electrically negatively charged.

In 4 also shows several possibilities of machine wetting surfaces 50M on which release agent T, which has not reached the disk wetting surface 50S, is to be deposited so that only these specifically defined and relatively small machine wetting surfaces become dirty and need to be cleaned.

In the upper part of the 4 These are positively charged, here earthed, sections in the front surface of the cutting frame 5, which faces diagonally downwards in the direction of passage 10*, which are arranged between the product openings 6.1 - 6.4, as well as preferably in the transverse direction in front of and behind the 1st and last of these product openings, and which are electrically insulated from the rest of the cutting frame.

In the lower part of the 4 These are - alternative or additional - strip-shaped, electrically positively chargeable, in particular earthed, machine wetting surfaces 50M, which in particular run approximately horizontally and are arranged in particular approximately at the level of the upper runs of the individual portioning belts 17a1 to 17a4, as well as in the transverse direction 11 in front of the first and behind the last portioning belt.

5 shows the function bar 23 together with its holding device 30, but without electrostatic equipment for reasons of clarity.

According to 5 the holding device 30 is on the cross member 2a of the base frame 2, which rises diagonally from front to back and is present in the top view at least on the operator side - facing the operator - as 2a , b shows, attached.

The holding device 30 is thus fastened to the base frame 2 with its rear end region 30A in the direction of travel 10* and carries the functional beam 23 on its other end region 30B, which is further forward and higher in the assembled state, which cantilevers on one side, namely with its end region 23A, to the end region 30B of the holding device 30 and from there extends with its longitudinal direction 23' in the transverse direction 11, preferably across all tracks SP1 to SP4 of the slicing machine 1.

In one of the two wider, here upwardly directed, peripheral walls 23b of the rectangular perimeter there is a large opening extending essentially over almost the entire length, which, as in 4b can be tightly closed by a tightly attachable and screwable bar cover 34.

How 5 shows, the holding device 30 has in its rear end region 30A a clamping device 40 comprising a press plate 39 which can be pressed by means of several clamping nuts 41 in the direction against the rear end face of the beam-shaped holding device 30 and can thus be non-positively fastened to one of the components running between them, for example the cross member 2a.

For this purpose, the clamping nuts 41, which in this case have corresponding handles, are screwed onto the free end of threaded bolts protruding from this rear end face, which pass through the press plate 39.

So that the functional bar 23 held at the other, front end region 30B can be positioned very variably with regard to position and rotational position about the transverse direction 11, the holding device 30 consists of a main arm 30.1, the rear end of which can be fixed to the base frame by means of the clamping device 40, and a pivot arm 30.2 attached to it so as to be pivotable about a pivot axis running in the transverse direction 11, to which the functional bar 23 can be fixed with one of its end faces, for example, and again so as to be pivotable about a pivot axis running in the transverse direction 11.

The connections 29.1 to 29.3 for the media required by the application unit 22, in particular spray units 22, in particular electrical current, electrical control signals, compressed air, are located on the function bar 23 and/or the individual application units 22, preferably easily accessible near the operator side B of the machine, in particular in the front side with which the function bar 23 is attached to the holding unit 30.

The individual application units 22 can each carry a storage container for the release agent, as shown on the rearmost application unit 22, or the media are supplied via a line to the function bar 23 and there distributed further to the individual application units 22 by means of indicated external lines eL.

In order to be able to reproduce the latter pivot position, an arc-shaped scale 35.3 is attached to the front surface of the function bar 23 and a pointer 36.3, which points to one of the markings of the scale 35.3, is attached to the pivot arm 30.2.

The corresponding swivel position between swivel arm 30.2 and function bar 23 is fixed by tightening a handwheel 37, with which the function bar 23 can be clamped in the set rotational position relative to the swivel arm 30.2.

Irrespective of the presence of the swivel arm 30.2, the support device 30, in particular its main arm 30.1, can consist of two parts that are displaceable relative to one another and thus telescopic in the longitudinal direction 30' - the greatest extension direction - of the bar-shaped holding device 30, in this case a base part 30.1 a, on which the clamping device 40 for fixing to the base frame 2 is located, and a support part 30.1 b, on which either the swivel arm 30.2 or directly the functional bar 23 is fixed.

The extent of the extension is again indicated by means of a scale 35.2 and a pointer 36.2 pointing to it, one of which is fixed to the base part 30.1 a and the other to the support part 30.1 b. The set expression position is again fixed by means of a handwheel 37, by means of which a clamping screw connected to it in a rotationally fixed manner is actuated, which clamps the two parts against each other.

In the released state of this clamping device, the relative longitudinal movement of the base part 30.1 a to the support part 30.1 b can be carried out by means of a threaded spindle, the drive pin 38 of which in the form of an external hexagon protrudes in this case from the upper end face of the main part 30.1 a.

In addition, an adjustment of the holding device 30, here the main arm 30.1, in particular its base part 30.1a, can be carried out relative to the clamping device 40 in the transverse direction to the longitudinal direction 30' of the holding device or 30.1' of its main part 30.1, the adjustment direction of which is also transverse to the transverse direction 11, the longitudinal direction 23', of the function bar 23.

There, too, a scale 35.1 and a pointer 36.1 directed thereon are provided to indicate the transverse adjustment, one of which is fixed to the clamping device 40 and the other to the holding device 30, in particular its main part 30.1.

LIST OF REFERENCE SYMBOLS

1

Slicing machine, slicer

1*

steering

2

Base frame

3

Knife

3

Rotation axis

3"

Knife plane, cutting plane

3a

Cutting edge

4

Feed conveyor, feed belt

5

Cutting frame

6a - d

Product opening

7

Cutting unit

8th

upper product guide, upper guide belt

8.1

Contact-Trum, Lower-Trum

8a

Knife-side pulley

8b

Deflection roller facing away from the knife

9

lower product guide, lower guide belt

8.1

Contact-Trum, Upper-Trum

9a

Glasses-side pulley

9b

Pulley facing away from glasses

10

Transport direction, longitudinal direction, axial direction

10*

Direction of flow through machine

11

1. Cross direction (width slicer)

11+

lower tangential direction

12

2. Transverse direction (height direction caliber)

13

Gripper unit, gripper carriage

14.14 a-d

Gripper

15

Spacers

16

Gripper claw

17

Discharge unit

17a, b, c

Conveyor belt

17a

Portioning belt

18

Gripper guide

19

Altitude sensor

20

Feed unit

21

Remnant conveyor

22

Application unit

23

Function bar

23A, B

End area

23'

Longitudinal direction

24

Discharge opening

24'

Spray direction

25

Contact wheel, spiked wheel

26

Collection container

27

insulation

28

Storage container

29.1 - 29.3

Connection

30

Holding device

30A, B

End area

30'

Longitudinal direction

30.1

Main arm

30.1a

Base part

30.1b

Supporting part

30.2

Swivel arm

31'

Transverse axis

32

Clamping screw

33

Extraction unit

33.1-.5

Suction opening

34

Beam cover

35.1, 35.2

scale

36.1, 36.2

pointer

37

Handwheel, clamping screw

38

Drive pin

39

Press plate

40

Clamping device

41

Clamping nut

50M

Machine wetting area

50S

Disc wetting area

K

Product, product caliber

KR

Remaining piece

S

disc

S1, S2

Main area

T

Release agent

P

portion

Claims (15)

Slicing machine (1), in particular slicer (1), for slicing product calibers (K) into product slices (S) and forming portions (P) therefrom, with - a cutting unit (7) with a rotating knife (3), - a feed unit (20) for feeding at least one caliber (K) in the feed direction (10) to the cutting unit (7) - a discharge unit (17) conveying the slices (S) in the transport direction (10) with at least one discharge belt (17a), - a dispensing unit (22) with at least one dispensing opening (24.1) for dispensing, in particular spraying, a liquid or powdery release agent (T) onto a wetting surface, namely a main surface (S1, S2) of a future slice (S) that is still on the caliber (K) or has already been produced as the slice wetting surface, - a control (1*) for controlling moving parts of the slicing machine (1), characterized in that - the dispensing unit (22) is an electrostatic dispensing unit (22), - in which a potential difference can be generated in particular between the release agent (T) dispensed via the dispensing opening (24.1) on the one hand and the desired wetting surface on the other hand, in particular by the two being able to be equipped with different electrical polarity via an electrical contact (+, -), in particular by electrically negative charging on the one hand and earthing on the other. Slicing machine (1) by Claim 1 , characterized in that - instead of or in addition to the disc wetting surface on the product, a machine wetting surface in the form of a defined, delimited surface of the slicing machine (1) is electrically grounded or electrically chargeable with a different polarity to the electrostatic charge of the separating agent (T) and/or - the dispensing unit (22), in particular its dispensing opening (24.1), and thereby the separating agent (T) flowing through it, is connected to a high-voltage generator that emits an electrically negative charge and the desired disc wetting surface and/or machine wetting surface is grounded and in particular is electrically insulated from the rest of the machine (1). (Spraying the front surface of the caliber:) Slicing machine (1) according to one of the preceding claims, characterized in that the discharge direction (24`), in particular the spray direction (24`), of the discharge opening (24.1) is directed towards the front face of the caliber (K) and the electrical contact (+) to the caliber (K) is - the gripper (14) holding the rear end of the caliber (K), in particular at least one gripper prong (16), and in particular the feed belt (4) consists of dielectric material or - the feed belt (4) of the feed unit (20) equipped with an electrically conductive outer side and/or - an electrical contact (+) arranged close to the front end, in particular on the rear side of the cutting frame (5), touching the caliber (K), in particular a contact wheel equipped with spikes, the spikes of which extend through openings in the feed belt (4) or in a lower product guide (8). Slicing machine (1) according to one of the preceding claims, characterized in that the discharge direction (24`), in particular the spraying direction (24`), of the discharge opening (24.1) is directed towards the front face of the caliber (K) and the electrical contact (+) to the caliber (K) is either the cutting frame (5) which is designed to be electrically conductive on the contact surfaces towards the caliber (K) and in particular the feed belt (4) is made of dielectric material - or the cutting frame (5) is electrically insulated from the caliber (K) and the electrical contact (+) to the caliber is an electrically isolated contact (+) separate from the cutting frame (5). (spraying the disc placed down:) Slicing machine (1) according to one of the preceding claims, characterized in that the discharge direction (24') of the discharge opening (24.1) is directed towards the upwardly facing main surface (S1) of the slice (S) lying on the discharge unit (22) and the electrical contact (+) to the caliber (K) - is either the discharge belt (17a) consisting of electrically conductive material at least on the contact surface towards the slice (S) - or is an electrical contact separate from the discharge belt (17a), in particular a contact wheel fitted with spikes, the spikes of which extend through openings in the discharge belt (17a). (Machine wetting surface:) Slicing machine (1) according to one of the preceding claims, characterized in that the machine wetting surface - is removed from the disk (S) by in particular at least 1/3 of the greatest extent of a disk (S), - is arranged in particular outside the mostly conical spray area of the discharge opening (24.1). Slicing machine (1) according to one of the preceding claims, characterized in that - the machine wetting surface, which is preferably connected to a collecting container at its lower end, is a surface running from top to bottom or a surface area of the machine (1), which is in particular heatable and is electrically insulated from the rest of the machine, - the machine wetting surface is arranged in particular between the product openings (6) or as a frame around the cutting frame (5). and/or - the machine wetting surface is arranged in particular between the parallel conveyor belts (17a) and/or laterally outside the conveyor unit (17). (Different potential differences:) Slicing machine (1) according to one of the preceding claims, characterized in that the electrical potential difference from the separating agent (T) to the slice (S) being produced or completely separated, i.e. the slice wetting surface, is greater than to the machine wetting surface. (Without spraying:) Slicing machine (1) according to one of the preceding claims, characterized in that the separating means (T) leaves the discharge opening (24.1) only due to gravity, in particular the discharge opening (24.1) is not a pressurized spray nozzle. Slicing machine (1) according to one of the preceding claims, characterized in that - the at least one discharge opening (24.1) is arranged in a functional bar (23) running transversely across the discharge unit (17). Method for operating a, in particular multi-lane, slicing machine (1), in particular a slicer (1) with - an application unit (22) for applying release agent (T) to a main surface (S1 - S4) of a future or already produced slice (S), - wherein release agent (T) is applied in the direction of a desired wetting surface of a, in particular only one, slice (S) by means of at least one application opening (24.1), in particular a slicing machine (1) according to one of the preceding claims, characterized in that - the release agent (T) is applied by means of an electrostatic application method, - in which the release agent (T) released via the application opening (24.1), in particular spray opening (24.1), on the one hand, and the desired slice wetting surface and/or the machine wetting surface on the other hand, in particular alternately over time (define), are electrically charged with different polarity, - in particular the release agent (T) is charged with at least 10 kV electrical voltage, preferably at least 40 kV electrical voltage, is electrically negatively charged and the desired wetting surface is electrically positively charged, in particular is grounded. (Gauge face as wetting surface:) Procedure according to Claim 11 , characterized in that - with the front, knife-side caliber face as the desired surface of use, the caliber (K) is contacted for the electrical charging with an electrical contact at a point in the longitudinal direction of the caliber (K) close to the caliber face, - in particular the caliber (K) is electrically insulated from the inner circumference of the product opening (6) of the cutting frame (5) through which it extends, or the cutting frame (5) consists of an electrically poorly (defined) or non-conductive material. (deposited disk as wetting surface:) Method according to one of the preceding method claims, characterized in that - with the top side of a disk (S) already placed on the conveyor unit (17) as the desired wetting surface, the disk (S) or the portion (P) to which the disk (S) belongs is contacted for the electrical charging with an electrical contact which is arranged in particular in the longitudinal direction of the portion close to the disk to be wetted, - in particular the disk (S) or the portions (P) are electrically insulated from the support surface on which it lies, in particular the conveyor belt (17a), or the support surface consists of a material which is poorly or non-conductive electrically. (Duration:) Method according to one of the preceding method claims, characterized in that - the release of release agent (T) through the discharge opening (24.1) is started before the disk (S) is completely separated from the caliber (K), in particular during the first third of the separation process or before the start of the separation process and/or - is continued until the disk (S) is completely separated from the caliber (K), in particular until the disk is in free fall, in particular until the disk (S) hits the support surface, in particular the discharge belt (17a). Method according to one of the preceding method claims, characterized in that - the machine wetting surface electrically charged for the electrostatic application process is removed from the disc wetting surface by at least 1/3 of the greatest extent of a disc (S) and/or - the machine wetting surface electrically charged for the electrostatic application process for removing the release agent deposited there (T) is used, in particular by being connected to a drain into a collecting container and/or by regularly, in particular automatically, removing the release agent (T) deposited on this machine wetting surface from there.

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