WO2014128145A1

WO2014128145A1 - Slicer with a vibrating knife

Info

Publication number: WO2014128145A1
Application number: PCT/EP2014/053194
Authority: WO
Inventors: Silvio Quaglia; Ralf Peter Müller
Original assignee: Gea Food Solutions Germany Gmbh
Priority date: 2013-02-19
Filing date: 2014-02-19
Publication date: 2014-08-28

Abstract

The present invention relates to a slicer comprising a moving knife, which cuts, in a cutting plane, slices from the front end of a product and transportation means, which moves the product intermittently or continuously towards the knife.

Description

Slicer with a vibrating knife

The present invention relates to a slicer comprising a rotating knife, which cuts, in a cutting plane, slices from the front end of a food product and transportation means, which moves the food product intermittently or continuously towards the knife and/or the cutting plane.

Such slicers are well known from the state of the art and are used for industrial purposes to cut for example 700 to 1000 slices per minute from a food product, particularly ham, cheese- or sausage-loaves. During the cutting action, high forces are needed to push or draw the knife through the product.

It was therefore the problem of the present invention to reduce these forces and/or to improve the cutting action and/or the cutting result.

This problem is solved by a slicer comprising a rotating knife, which cuts, in a cutting plane, slices from the front end of a food product and transportation means, which moves the food product intermittently or continuously towards the knife and/or the cutting plane, wherein the slicer comprises means to induce vibrations into the knife.

The disclosure regarding this subject matter of the present invention can be combined with the disclosure regarding the other subject matters of the present invention and vice versa. The disclosure regarding this embodiment of the present invention also applies to the other embodiments of the present invention and vice versa.

The present invention relates to a slicer, which comprises a rotating knife. The knife of this slicer cuts slices from a food product such as ham, cheese or a sausage. Such a knife can be for example a disc-shaped knife or a so called spiral knife. This knife rotates in a cutting plane and cuts slices from the front end of a product, preferably a ham-, a cheese- or a sausage-loaf, which is moved by transportation means continuously or intermittently towards the knife. The movement of the knife can be a pure rotation or a rotation combined with an orbital movement of the knife. The movement of the product during two cutting actions determines the thickness of the respective slice. According to the present invention, the slicer comprises means to induce a vibration into the knife; i.e. vibration energy is provided by a preferably external source and transferred into the knife. Due to this vibration of the knife, the forces needed for the cutting action are reduced, the cutting action itself and/or the cutting result is improved. Preferably, the vibration of the knife, i.e. its frequency and/or its amplitude can be adjusted independently from the motion of the knife, particularly its speed of rotation. Preferably, the vibration of the knife is altered based on the food product to be cut. The vibration of the knife can be in a low or a high frequency range or in a combination of a multitude of frequencies. Preferably the frequency is in the resonance frequency range of the knife and/or the resonance frequency range of the knife plus the rotor and/or the resonance frequency range of the knife, the rotor and the drive shaft which rotates the knife. More preferably, the frequency of the vibration is in the range of ultrasonic sound.

Preferably, the vibrations are induced by direct or indirect means, wherein direct means are at least temporarily in direct contact with the knife and indirect means transfer the vibrations via a different medium, for example air into the knife. The direct means to induce vibrations can be for example a piezo element, which is at least temporarily in direct contact with the knife and/or solidborne sound, and/or vibration transfer to the knife via hydraulics. Alternatively or additionally, the vibrations can be induced into the knife by indirect means such as sound waves, preferably airborne sound, magnetic forces and/or inductive forces. More preferably, the vibration means is a piezo element.

The means to induce the vibration into the knife can be fixed to a nonmoving, preferably non rotating part or can be comoving, preferably corotating with the knife. Preferably, the vibration means are directly or indirectly fixed to the frame of the inventive slicer. Even more preferred, the vibration means are located in the rotor housing of the slicer.

The means to induce the vibration preferably operates with electrical energy. The energy transfer to this means is preferably by induction, by capacitance or via electric conductance.

Preferably, the direction, in which the knife vibrates, is parallel and/or perpendicular to the cutting plane.

Preferably, the vibration of the knife is induced into the knife close to the axis of rotation of the knife.

In another preferred embodiment, particularly the cutting edge of the knife vibrates.

In a preferred embodiment, the inventive slicer comprises a sensor which detects product properties, for example the temperature, the salt content and/or the texture of the product and adjusts the vibration of the knife; e.g. the amplitude and/or the frequency of the vibration of the knife accordingly. According to another preferred embodiment, the sensor senses the machine performance, for example the energy uptake during the cutting action and adjusts the vibration; e.g. the amplitude and/or the frequency of the vibration of the knife such, that this performance is optimized.

In a preferred embodiment, the knife of the slicer can be displaced temporarily, preferably parallel to its axis of rotation away from the cutting plane in order to execute idle cuts, i.e. rotations of the knife, in which no slices are cut from the front end of the product. Preferably, no vibration is induced into the knife during these idle cuts. This can be for example achieved by moving the knife away from the vibration means and/or by stopping the vibration of the vibration means. In case idle cuts are utilized by moving the knife away from the cutting plane, the vibration means preferably stay stationary during this movement. Preferably, the knife and/or the drive shaft that rotates the knife are moved away from the vibration means during an idle cut.

The knife, the rotor and/or its drive shaft are preferably supported at the frame of the inventive sliced by a floating bearing, so that the knife and/or the drive shaft can move parallel to the direction of the vibration. Such a bearing can be, for example a membrane.

Another subject matter of the present invention is a method to slice a food product into a multitude of slices by a moving knife, which cuts the slices from the front end of the product in a cutting plane, wherein a vibration is induced into the knife at least temporarily during the cutting action and wherein the cutting force and/or a property of the food product is measured and wherein the amplitude, the frequency and/or the direction of the vibration is altered based on this measurement,

According to the inventive method, a vibration is induced into the knife at least temporarily during the cutting action of the knife through the product, i.e. the vibration is induced into the knife at least temporarily, while the knife is in contact with the product. This reduces the force needed to cut a slice from the product and/or improves the cutting action and/or the cutting result. Preferably, the direction of vibration of the knife is parallel and/or perpendicular and/or tangential to the cutting plane.

More preferably, the vibration mode, e.g. the frequency and/or the amplitude of the vibration and/or the direction of the vibration, is changed during the rotation of the knife. For example, a different vibration can be applied to the knife, while the knife enters the product in comparison to the subsequent cutting action. More particularly, no vibration is needed, when the knife is not in contact with the product.

According to the invention, the force needed to cut a slice is measured preferably for each and every slice which is cut. Alternatively, the force is measured according to a certain pattern, e.g. very other slice or one slice per portion.

Due to the measurement of the cutting force, the vibration can be altered during the slicing of a certain food product or during the slicing of a portion and/or between the slicing of two slices. The vibration can for example be altered based on the properties of the product, for example the ratio of lean- and fat-meat.

According to yet another preferred embodiment of the present invention, the properties of the food product, for example its internal structure, preferably as a function of its length, is determined, preferably upfront, and the vibration means are adjusted accordingly during the slicing of the food product.

Preferably, the temperature of the food product is determined and based on this measurement, the vibration is adjusted.

Preferably, the vibration, particularly its amplitude and/or its frequency and/or its direction is optimized by minimizing the cutting forces. Prior or during the cutting of a slice, the vibration is preferably changed and the resulting cutting force is measured, preferably in order to archive a minimized cutting force. This reduced cutting force saves energy and/or reduces the impact of the cutting on the knife and/or product. The force can be measured several times during the slicing of the product for example to account for changes of the mechanical properties within the product and/or the knife. After each measurement, the vibration can be altered based on the result of the measurement.

The cutting force can be determined by any sensor known to the person skilled in the art. Preferably the energy uptake and/or the lag error of the motor that moves, preferably rotates, the knife during the cutting of a slice is measured. Alternatively or additionally, the counterforce of the support of the product during the cutting of a slice is measured.

Preferably, the optimal vibration, e.g. frequency, amplitude, and/or direction is determined for each product upfront and this information can be stored and uploaded for each product. In a preferred embodiment, the knife executes idle cuts, for example in order to transport a portion, which comprises a multitude of slices, away from a portioning table, on which the slices drop after their cutting. Preferably, no vibration is induced into the knife, while the knife performs its idle cuts.

The invention is now disclosed according to the figures. This explanation applies to both inventions. The explanation does not limit the scope of protection.

Figures 1 - 3 show an embodiment of the inventive sheer, respectively.

Figure 1 shows the inventive slicer 5 which comprises a knife 1 1 , which is rotated by a rotor 15. In the present case, the knife 1 1 is a disc-shaped knife and the rotor 15 rotates the knife around its center axis. Simultaneously, the center axis of the knife performs an orbital movement, which brings the rotating knife into and out contact with the product 2. The knife 11 cuts in a cutting plane 6 slices 12 from the front end of the product. These slices drop in the present case onto a portion table 1 , on which they are accumulated to portions 14, comprising a multitude of slices, which are after the portion is completed transported away, for example to a packaging unit. The product 2 is transported by transportation means 4, in the present case two endless belts, towards the knife 1 1 and/or the cutting plane 6. This transportation can be continuously or intermittently. The thickness of a slice is determined by the transport distance of the product between two cutting actions. At its butt end 13, a gripper can be provided to grip the butt end of the product in order to stabilize it, particularly to stabilize the butt end of the product during its slicing. In order to, for example gain time to transport portion 14 away from the transport table, the knife preferably executes idle cuts, during which it maintains its speed of rotation, but does not cut slices from the front end of the product. This can be for example achieved by moving the knife 1 1 preferably parallel to its axis of rotation away from the cutting plane 6, in the present case by moving the knife temporarily to the left hand side.

According to the present invention, the inventive slicer now comprises vibration means 3, which are in the present case installed at the center axis of the knife and which induce a vibration into the knife. Due to this vibration, the cutting action of the knife is improved, i.e. less energy is needed and/or the cutting action itself is improved, which results in improved slices. The vibration can be parallel to the cutting plane and/or perpendicular to the cutting plane. The vibration can be induced directly for example with a piezo element 3 and/or indirectly for example by sound waves. Preferably, during idle cuts, no vibration is induced into the knife. The inventive slicer may comprise a sensor (not depicted), which senses product properties, for example the temperature of the product, the salt content and/or mechanical properties of the product. Based on the product properties identified, the performance of the vibration means is optimized; e.g. the frequency and/or the amplitude of the vibration. Alternatively or additionally, the sensor acquires data of the machine performance, for example the energy uptake during the cutting action and/or the vibration of the knife during entering the product and/or during the cutting of the product and optimizes the vibration means to improve the machine performance. The optimization can be an optimized frequency and/or optimized amplitude of the induced vibration of the knife.

Figure 2 shows yet another embodiment of the inventive slicer and the inventive method. In the present case, the product 2 is driven by an upper and a lower transportation means 4^', 4^". However, the person skilled in the art understands, that the transportation means can be designed differently. Furthermore, in the present case, the vibration means 3, for example a piezo element, is provided in the rotor housing 17 of the inventive slicer. The knife 1 1 is in the present case driven by a drive shaft 16, which is supported at the rotor housing and/or the frame of the slicer such, that it can move relative to the rotor housing and/or the frame of the slicer as the depicted by the double arrow 18, i.e. parallel to the direction of movement of the product 2 and/or parallel to the movement of the transportation means 4. In the present case, the vibration means 3 are in direct or indirect contact with the drive shaft 16 of the knife 11. Thus, a vibration induced into the drive shaft is transferred to the knife 11 , so that the knife 1 1 vibrates. The bearing utilized in the present case for the knife and/or the drive shaft is a so called floating bearing, so that the drive shaft and/or the knife can move in the direction as depicted by reference sign 18. Such a bearing can be, for example utilized by a ball bearing or by a membrane. This movement 18 can also be utilized for idle cuts, i.e. that the knife is moved away from the front and off the product while it rotates in order to avoid cutting off further slices from the food product 2. However in the case of an idle cut, the amplitude of the movement 18 is larger in comparison to the amplitude of the vibration.

Figure 3 shows yet another embodiment of the inventive slicer. In principle, reference can be made to the embodiments according to figures 1 and 2. However, in the present case, the vibrating means 3 directly induce a vibration into knife 1 1 , preferably in the vicinity of the cutting edge of the knife. This can be achieved by a direct or indirect contact of the vibration means 3 with the knife 11 , However, an indirect contact of the vibrating means 3 with the knife 11 is preferred. The vibration can be induced to the knife for example by sound waves.

Preferably, the knife in all embodiments of the present invention is activated by ultrasonic sound.

More preferably, the knife vibrates in its resonance frequency.

List of reference signs:

1 portioning table

2 product

3 vibration means

transportation means

' lower transportation means

" upper transportation means

5 slicer

6 cutting plane

11 knife, circular knife

12 slices

13 butt-end

14 portion

15 rotor

16 drive shaft

17 rotor housing

18 movement of the driveshaft and/or the knife due to the vibration means 3

Claims

Patent claims:

1. Slicer (1) comprising a rotating knife (11), which cuts, in a cutting plane (6), slices (12) from the front end of a product (2) and transportation means (4), which move the product intermittently or continuously towards the knife (11), characterized in, that the slicer comprises means to induce vibrations into the knife.

2. Slicer (1) according to claim 1 , characterized in that the vibrations are by direct or indirect means.

3. Slicer (1) according to one of the preceding claims, characterized in, that the vibration of the knife is parallel and/or perpendicular to the cutting plane.

4. Slicer (1) according to one of the preceding claims, characterized in, that it comprises a sensor which detects product-properties and/or the machine-performance, wherein the vibration is adjusted based on the signal of the sensor.

5. Slicer (1) according to one of the preceding claims, characterized in, that the knife (11) is driven by a drive shaft and that the vibration means (3) are in direct or indirect contact with the drive shaft.

6. Slicer (1) according to claim 5, characterized in, that the vibration means move the drive shaft parallel to the direction of the movement of the transportation means (4).

7. Slicer (1) according to claim 5, characterized in, that the vibration means (3) directly induce vibrations into the knife (1 1).

8. Slicer (1) according to one of the preceding claims, characterized in, that the vibration means are stationary.

9. Slicer (1) according to one of the preceding claims, characterized in, that the knife and/or the drive shaft is supported by a floating bearing.

10 Slicer (1) according to one of the preceding claims, characterized in, that the vibration means is a piezo-element.

11. Method to slice a food product (2) into a multitude of slices (12) by a rotating knife, which cuts the slices (12) from the front end of the food product in a cutting plane (6), wherein a vibration is induced into the knife at least temporarily during the cutting action, characterized in, that the cutting force and/or a property of the food product is measured and the amplitude, the frequency and/or the direction of the vibration is altered based on this measurement.

12. Method according to claim 11 , characterized in, that the knife vibrates parallel and/or perpendicular to the cutting plane (6).

13. Method according to claims 11 or 12, characterized in, that the vibration mode is changed during one rotation of the knife.

14. Method according to claims 1 1 - 13, characterized in, that the energy uptake and/or the lag error of the motor that moves, preferably rotates the knife during the cutting of a slice is measured.

15. Method according to claims 11 or 14, characterized in, that the counterforce of the support of the product during the cutting of a slice is measured.

16. Method according to one of claims 11 - 15, characterized in, that the knife executes idle cuts and that during the idle cut no vibration is induced into the knife.