EP1800811B1 - Method to slice an elongated product - Google Patents

Abstract

The method involves disposing the material strands (2) on a moving equipment and pushing the strands to a cutting mechanism. The length of the strands measured by the detecting mechanism in the feeding direction is defined such that product of feeding speed and the time required for the strands to pass the measuring point are determined. An action point (15) is determined based on the determined length of the strands. An independent claim is also included for a device for cutting the material strands.

Description

The invention relates to a method for cutting a Gutstrangs into slices, in which the Gutstrang is placed on a feed device and advanced by means of the feed device to a cutting device, wherein by means of a detection device geometric data of the Gutstrangs are detected, from which by means of a control device, the intervention of a Gripping element of a gripping device is determined so that the measured in the feed direction of the detection device length of the Gutstrangs is determined by the product of feed rate and the time that the Gutstrang needed to pass a stationary measuring point is formed, and wherein the engagement point in dependence the determined length of the Gutstrangs is determined and brought the gripping member at the point of engagement with the Gutstrang engaged and then moved with the feed rate together with the Gutstrang to the cutting device where the gut strand is sliced. Such a method is described in US Pat GB-A-2 386 317 disclosed.

The method described above and devices for carrying it out are generally known and are used in particular in a continuous mode of operation when a disc-precise cutting of material strands is to be realized. In the known devices, the feed device is usually designed as a conveyor belt and the detection device, for example in the form of a laser camera, which detects the geometric data of the Gutstrangs, in particular its profile at a sufficient distance in front of the cutting device. In the case of the profile shape, the geometric shape of the rear end section of the material strand, viewed in the feed direction, is of particular interest, where the gripping element of the gripping device penetrates. Known gripping members are formed, for example, as a fork-like trident or as angled claws or gripper hooks. The Gutstrang must have a sufficient accumulation of material in the region of the point of engagement of the gripping member, so that the gripping member in the engaged state can exert a sufficiently large force on the Gutstrang. Thus, the gripping member must in particular ensure that the Gutstrang despite the forces acting on its front end forces of the cutting member not unintentionally and uncontrollably changed its position. Otherwise, not geometrically exact slices would be the result, in particular slices with not mutually parallel cut surfaces. The known device is therefore determined on the basis of the evaluation by means of the laser camera, the point of engagement of the gripping member so that in any case, the required holding force can be transmitted from the gripping device to the Gutstrang.

Since good strands can sometimes have a complex geometry, in particular in the end sections, the calculation algorithms for determining the optimal engagement point are complicated and the calculation time required for this purpose is long. This is in contrast to the demand for high performance and short processing times which is fundamentally present in food processing. Furthermore, the laser camera used in the known devices is expensive, which also applies to the evaluation electronics included in the control device.

From the GB 2 386 317 A also shows a cutting device, however, in which the Gutstrang between an upper and lower conveying means is conveyed in the direction of the cutting device. While the lower conveyor consists of a conveyor belt with a greater width than the Gutstrangs, the upper conveyor is formed of two parallel conveyor belts of smaller width, wherein between the two upper conveyor belts, a gap remains, in which a gripping device is arranged. The upper conveyor belts are separately variable in height, which is to prevent tilting of gut strands with irregular cross-section.

As an example of a cutting device for cutting discs of the same nominal weight of inhomogeneous material strands is still the DE 44 10 596 A1 in which a method is disclosed in which the Gutstrang for determining the density distribution is irradiated over its length by a light source. The amount of light exiting on the opposite side serves as a measure of the locally determined density of the material in order to be able to produce wheels of exact weight in this way.

The state of the art further includes cutting devices in which the feed device is not formed as described in the input devices from a conveyor belt, but has the shape of a slide, with a Gutstrang is advanced in a shaft-like loading area on the cutter. In contrast to the previously described continuously operated devices, in which successively good strands are moved to the cutting device with a short distance to each other, the latter devices operate in discontinuous operation. A gripping device is integrated in these devices in the feed slide, wherein an automatic intervention is realized in that with the help of a rocker mechanism, an intervention of the gripping member in the end of the Gutstrangs only then takes place when the feed carriage runs on the end of lying in the Einlegeschacht Gutstrang. The engagement point thus has a fixed distance from the rear end of the Gutstrangs associated contact surface of the feed slide. With such a functioning automatic gripping system knowledge about the geometry of the end portion of the Gutstrangs are not required because regardless of the specific shape of the Gutstrangs the engagement of the gripping member always takes place at the right time and in the right place (with respect to the Gutstrang). A continuous operation is not possible with such a device, however; Rather, the insertion of the device after cutting a Gutstrangs, the detachment of remaining in the end effector gripping member and the retraction of the feed device must be equipped with the gripping device before restarting with a new Gutstrang.

In the known from the prior art cutting devices, the focus is often placed on the formation of discs of the same weight, ignoring what size has the remaining remainder. Often sections of a Gutstrangs remain unused, so that the utilization of the food to be cut leaves much to be desired.

task

The invention has for its object to provide a method and an apparatus for cutting a Gutstrangs, in which or in the continuous continuous feed of a plurality of consecutively on the cutting device to moving Gutstrange with simple means the utilization of the food to be cut is increased.

solution

The object is achieved by a method having the features of claim 1.

Based on a method of the type described above, this object is achieved in that the disk thickness is determined as an integer divisor a useful length, which is based either from the distance between the front end of the Gutstrangs and the point of engagement of the gripping member, reduced by a safety distance between cutting member and gripping member, calculated [Alternative A] or the measured length of the Gutstrangs corresponds to [Alternative B].

In contrast to previously known methods, in which a complex geometry of the Gutstrangs is detected in terms of many dimensions using a complicated detection technique in the form of a laser camera, the inventive method comes with a mere length measurement. In this case, the other geometric features of the Gutstrangs are disregarded and the point of engagement of the gripping member is made solely dependent on the position of the rear end of the Gutstrangs in the feed direction, depending on the product of the end of the Gutstrangs a fixed distance for the intervention site is selected. If the feed rate is constant over time, the length calculation is done simply by multiplying the speed by the pass time of the product strand. The Passierzeit is defined so that it starts to run when the front end of the Gutstrangs in the feed direction reaches a measuring point and the time ends when the rear end of the Gutstrangs also reaches this point in the feed direction. If the feed rate is not constant over time but has a known, changing profile, the length of the product strand is calculated as the integral of the feed rate over the pass time.

Even if the determination of the point of engagement has only a slightly greater inaccuracy or uncertainty than the known method of precise geometry detection, depending on the length of the strand, the great advantage of the method according to the invention is its simplicity, since only the installation of a stationary measuring point is required for the implementation , The uncertainty about the concrete geometry of the rear Gutstrangendes that can not be detected by the method according to the invention can be easily compensated by the fact that the selected distance between the detected Gutstrangende and the entry point of the gripping member is provided with a certain security surcharge.

The remaining length of the Gutstrangs after deduction of both a minimum distance of the rear end of the engagement point as well as a safety distance of the cutting member of the gripping member (when cutting the last disc) gives the useful length of the Gutstrangs. For each Gutstrang the slice thickness is redefined as an integer divisor of the respective effective length. This ensures that apart from the technically caused by the safety distance and the distance between the end of the Gutstrangs and the remaining piece remains no further remainder of the Gutstrangs, which in turn increases the utilization of the food to be cut.

In the event that the thickness of the normally accruing remnant corresponds at least to the specified slice thickness, the remainder can also be used as a (last) slice or as part thereof, so that no remainder remains and the Gutstrang is fully utilized. Accordingly, then corresponds to the useful length of the entire length of the Gutstrangs and the utilization of the Gutstrangs is maximum.

Advantageously, the thickness of the disc is determined according to alternative A, if the disc thickness is smaller than the sum of the safety distance and a minimum distance of the point of engagement of the gripping member from the rear end of the Gutstrangs, so at thinner disc thicknesses. In contrast, the disc thickness is determined by Alternative B, if the disc thickness is greater than the sum of the safety distance and the minimum distance of the point of engagement of the gripping member of the rear end of the Gutstrangs, so with thicker disc thicknesses. Accordingly, depending on the thickness of the disk, it is possible to choose between two alternatives for the exact definition of the disk thickness, so that the method can be optimally utilized depending on the application.

In an advantageous embodiment of the method according to the invention, a setpoint value for the slice thickness is determined and the quotient of useful length and setpoint value rounded in an integer manner and implemented as an integer divisor for determining the further used value of the subsequent cutting operation Disk thickness used. The disk thicknesses of the various cut Gutstränge therefore slightly deviate from the target value of the disk thickness, which, however, due to the comparatively large length of Gutstrange in contrast to the small disc thickness is not significant.

Moreover, it is advantageous if an upper or lower setpoint value for the slice thickness is determined and the quotient of useful length and setpoint value rounded up in an integer or rounded down to an integer and used as integer divisor for determining the further used value of the slice thickness to be realized in the subsequent cutting operation. Thus it is achieved that the cut slice thicknesses either do not exceed an upper setpoint value or vice versa, do not fall below a lower setpoint value, which can be a significant requirement for certain applications.

Advantageously, in the case of the method according to the invention, a plurality of strands of material which are spaced apart from one another in the feed direction are fed successively one after the other by means of the feed device. Thereby, continuous continuous operation can be ensured, resulting in high productivity of the process. Appropriately, a loading of the conveyor belt should be done in regular and shortest possible intervals in succession, in order to further optimize the operation, but this is not absolutely necessary. The simplicity and speed with which the detection unit performs the measurement makes flexible assembly unproblematic.

In order to design the procedure as far as possible regularly, it is advantageous that the feed device, which is preferably designed in the form of a conveyor belt, is moved continuously and / or at a constant speed. The length calculation is carried out simply by multiplying the speed by the passing time of the material strand at the measuring point. The calculation process, which the detection device makes, and the associated data flow to the control unit expires in a very short time, whereby the speed at which the conveyor belt is moved, practically only of the duration of the actual cutting process and the eventual return driving the gripping member depends on a waiting position and can be adjusted to this adjusted.

According to one embodiment of the invention, the gripping member is brought out of engagement with the Gutstrang before reaching the cutting member and then moved against the feed direction back to a waiting point at which it is brought into engagement with the next Gut strand. In this case, the remaining piece or the last slice of Gutstrangs be solved by a loosening device of the gripping member and remain in the field of cutting device in a collection or transported to the cut slices. The gripping member is moved back empty to the waiting place. Alternatively, the remnant can be solved only in the waiting area by the release device of the gripping member. The release device may be formed as a comb, which penetrates into the interstices of the gripping member and thus "combs out" the remaining piece. The removal of the remaining piece is automated.

It is understood that the gripping device can also be equipped with two or more than two gripping members, which are then brought in the manner of a rotating system with the respective Gutstrange engaged or disengaged again. While a gripping member is freed from the remnant piece or the last disc and driven back to his waiting place, a second gripping member is already in the process of grabbing a newly arriving Gutstrang. This makes a further increase in productivity feasible.

Advantageously, the gripping member is brought by a vertical lifting movement or by a pivoting movement about a horizontal axis with the Gutstrang in and disengaged. The gripping member may be arranged on a carriage, whereby it can be moved in a simple manner in the horizontal direction along the conveyor belt.

embodiment

The invention will be explained below with reference to an embodiment.

Figur1:

eine perspektivische Darstellung einer Vorrichtung zum Schneiden eines Gutstrangs unter einem Blickwinkel schräg auf die Vorschubeinrichtung,

Figur 2:

wie Figur 1, jedoch in einer anderen Perspektive und in einer vergrößerten Darstellung, und

Figur 3:

wie Figur 2, jedoch in einer anderen Perspektive.

Show it:

Figur1:

a perspective view of an apparatus for cutting a Gutstrangs at an angle obliquely to the feed device,

FIG. 2:

as FIG. 1 but in a different perspective and in an enlarged view, and

FIG. 3:

as FIG. 2 but in a different perspective.

In FIG. 1 a device 1 for cutting a Gutstrangs 2 according to the inventive method is shown in a perspective view. The device 1 consists of a feed device 3, a detection device 4, a gripping device 5, a non-visible control device and a cutting device, which is also not visible in the interior of the device 1 is arranged. The feed device 3, to which the product strands 2 are consecutively placed, is a conveyor belt running at a constant speed, whose transport belt 7 is deflected by respective driven rollers 8 located at the ends of the conveyor line in the opposite direction, thus effecting endless conveyance.

The detection device 4 detects the geometric data of the material strand 2, in particular its length L. At a measuring point 9, which is located in the feed direction 10 in the beginning of the conveyor belt, a light barrier 11 by means of a light emitter 12 on one side of the conveyor belt and a light receiver 13 generated on the opposite side of the conveyor belt. Reaches the start of a 6 _a material strand 2, the light barrier 11, it will be up to the time at which the material strand has _a 2 thereof, the light barrier 11 is happening end 6, interrupted. The control device multiplies the Passierzeit the Gutstrangs 2 at the measuring point 9 with the speed of the conveyor belt and receives the length L of Gutstrangs 2. With this result, the control device determines taking into account a minimum distance at the end of the 6 _{e of} the Gutstrangs 2 the optimal engagement point 15 for the gripping member 14. The minimum distance from the end 6 _{e of} the Gutstrangs 2 is required because of a secure engagement of the gripping member 14 is a sufficiently large Material collection must be present, which is not always guaranteed towards the end of Gutstrangs 2. Furthermore, a safety distance a _s between a cutting member of the cutting device and a gripping member 14 of the gripping device 5 is set. The safety distance a _s of cutting member and gripping member 14 serves to avoid damage to the cutting member or the gripping member 14. The remaining length of Gutstrangs 2 after subtracting the minimum distance a _{m of} the rear end 6 _e and the engagement point 15 and the safety distance a _s of cutting member and Gripper 14 is defined as effective length NL of Gutstrangs 2. In order to cut the Gutstrang 2 optimally rest optimized slice thickness is set for each Gutstrang 2, as an integer divisor of the respective useful length NL The used to determine the thickness of the disc integer divisor example, by dividing the Effective length NL determined by an upper target value for the disk thickness, this quotient being rounded up so that the thickness of the cut disks does not exceed the upper target value of the disk thickness.

If the thickness of the remaining piece 21 actually obtained reaches at least the slice thickness to be realized, then the remainder piece 21 is used as the last slice or part thereof and the good strand 2 is completely cut open. In this case, the useful length NL corresponds to the length L of the material strand 2, which, taking into account the target slice thickness, is cut into an integral number of slices.

In FIG. 1 has the Gutstrang the measuring point has not yet reached and the light barrier is not interrupted.

The gripping device 5 consists of the gripping member 14 which is mounted with an arm 17 on a rod 16 perpendicular to this. This rod 16 is mounted in a vertical slot 23 of a carriage 18 parallel to the conveying plane slidable. By a lifting movement within the slot 23, the gripping member 14 is brought from a waiting position, in which the gripping member 14 is located at a distance above the top of the Gutstrangs 2, by a lowering in the vertical direction with the Gutstrang 2. The gripping member 14 has claws. 19, which is inserted at the engagement point 15 in the Gutstrang 2 become. The movable in (and against) the feed direction 10 by means of its own drive carriage 18 ensures that the gripping member 14 can follow the Gutstrang 2 without resistance in the direction of cutting member and stabilizes it during the cutting process. This ensures a consistent geometry of the discs.

The cutting operation takes place by means of the cutting device, which is not shown in the figures. The cutting member consists inter alia of a crescent-shaped knife, which performs a rotary motion at high speed. The cutting device is located in a knife box 20, which is attached around the cutting device for safety reasons. The knife box 20 is secured so that it can only be opened when the knife is stationary.

After completion of the cutting process remains a remnant piece 21 on the gripping member 14, whose length consists of the sum of the minimum distance at and the safety distance a _s . The remaining piece 21 of the Gutstrangs 2 is by means of a release device 22, released from the gripping member 14 and in a collection container, which is not shown here, collected. The release device 22 is formed as a comb, which can engage in the interstices of the individual claws 19 of the gripping member 14 and thereby pushes the remainder piece 21 out of the gripping member 14, but the actual remaining piece 21 can be used as the last slice or part thereof due to its usable thickness will be transported to the cut slices.

After the remaining piece 21 has been released from the gripping member 14, this is moved by means of the carriage 18 against the feed direction 10 of the conveyor belt to a waiting point. There it is ready for the intervention in a next Gutstrang 2.

FIG. 2 shows the device 1 as in FIG. 1 but in a different perspective and in an enlarged view. The perspective illustrates the gripping member 14 with its claws 19 and the release device 22 well. The gripping member, or its claws 19, are brought into engagement with a product strand 2. The entire gripping device 5 follows the Gutstrang 2 in the feed direction 10, thus ensuring a stable leadership.

FIG. 2 shows another strand 2, which passes the measuring point 9. The light barrier 11 is interrupted. By way of example, the required minimum distance a _m from the end 6 _{e of} the material strand 2 and the engagement point 15 as well as the safety distance a _s of the gripping member 14 and the cutting member are indicated on a further material strand 2 to be located on the cutting device. The sum of these two lengths gives the length of the remainder piece 21 and the remaining part of the product strand 2 is defined as its useful length NL. Only in the case where the length of the remnant piece 21 is at least equal to the thickness required for a disc and used as such, the useful length NL of the length L of the Gutstrangs 2 total.

In FIG. 3 the device is from a different perspective than in FIG. 2 The feed device 3 with material strands 2 arranged thereon, the gripping device 5 and the detection device 4 can be seen.

LIST OF REFERENCE NUMBERS

1

contraption

2

string of material

3

feeder

4

detector

5

gripper

6 _a

Beginning

6 _e

The End

7

Conveyor belt

8th

roll

9

measuring point

10

feed direction

11

photocell

12

light emitter

13

light receiver

14

gripping member

15

surgical site

16

pole

17

poor

18

carriage

19

claw

20

knife box

21

remnant

22

release device

23

Long hole

L

length

NL

Effective length

a _m

minimum distance

a _s

safety distance

Claims (8)

1. A method for the cutting of a material strand (2) into slices wherein the material strand (2) is placed on a feeding device (3) and pushed forward on to a cutting device by means of the feeding device (3), wherein geometrical data of the material strand (2) is sensed by means of a sensing device (4), from which with the help of a control device the intervention point (15) of a gripping organ (14) on a gripping device (5) is determined so that the length (L) of the material strand (2) measured in feed direction (10) by the sensing device (4) is determined, in that the product from feed speed and the time required by the material strand (2) for passing a stationary measuring point (9) is formed and wherein the intervention point (15) is determined as a function of the determined length (L) of the material strand (2) and the gripping organ (14) at the intervention point (15) is engaged with the material strand (2) and subsequently moved with the feed speed together with the material strand (2) towards the cutting device, where the material strand (2) is cut into slices, characterized in that the slice thickness is determined as whole-number divisor of its useful length (NL), which is calculated either from the spacing between the front end (6a) of the material strand (2) and the intervention point (15) of the gripping organ (15) reduced by a safety spacing (as) between cutting organ and gripping organ (14) [alternative A] or corresponds to the measured length (L) of the material strand (2) [alternative B]
2. The method according to Claim 1, characterized in that

   - alternative A is applied when the slice thickness is smaller than the sum of the safety spacing (a_s) and the minimum spacing (a_m) of the intervention point (15) of the gripping organ (14) from the rear end (a_c) of the material strand (2), and that

   - alternative B is applied when the slice thickness is greater than the sum of the safety spacing (a_s) and the minimum spacing (a_m) of the intervention point (15) of the gripping organ (14) from the rear end (a_c) of the material strand (2).
3. The method according to Claim 1 or 2, characterized in that a set value for the slice thickness is determined and the quotient of useful lengths (NL) and set value is whole-number rounded and as whole-number divisor is utilised to determine the further used value of the slice thickness to be realised during the subsequent cutting operation.
4. The method according to any one of the Claims 1 to 3, characterized in that an upper or lower set value for the slice thickness is determined and the quotient of useful length (NL) and set value is rounded up by whole numbers or rounded down by whole numbers and as a whole-number divisor is utilised to determine the further used value of the slice thickness to be realised during the subsequent cutting operation.
5. The method according to any one of the Claims 1 to 4, characterized in that continuously successively a plurality of material strands (2) spaced from each other in feed direction (10) are pushed forward by means of the feed device (3).
6. The method according to any one of the Claims 1 to 5, characterized in that the feed device (3) which preferentially is embodied in form of a belt conveyor, is moved continuously and/or with constant speed.
7. The method according to any one of the Claims 1 to 6, characterized in that the gripping organ (14) is disengaged from the material strand (2) before reaching the cutting organ and subsequently moved back to a waiting point against the feed direction (10) at which it is engaged with the next following material strand (2).
8. The method according to any one of the Claims 1 to 7, characterized in that the gripping organ (14) is engaged with and disengaged from the material strand (2) through a vertical lifting movement or through a swivel movement about a horizontal axis.

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