Automatic Sausage Slicing and Weighing System

The present invention relates to a method of and apparatus for automatically slicing and weighing sausage. More particularly this invention concerns such an apparatus used in the retail trade for preparing packages of sliced cold cuts.

In the retail trade it is standard practice for a customer to order, for example, a quarter pound of sliced salami. In a shop selling fresh products the vendor normally then places the whole salami onto the slicing machine, sets the machine to produce slices of the requested or standard thickness for the particular cold cut, and cuts off a number of slices whose aggregate weight the vendor judges to be approximately the requested weight. During this procedure the vendor, especially when not highly experienced, interrupts the slicing operation to set the already cut slices down on the scale to verify the weight. Such a procedure is time consuming and, therefore, uneconomical.

Machines are also known, such as described in my copending and commonly assigned application Ser. No. 901,710 filed 1 May 1978 and in my jointly filed application Ser. No. 911,290, whose entire disclosures are herewith incorporated by references, which automatically form a succession of slices and even deposit this succession of slices on a support table in a plurality of rows, with the slices in each row being offset to each other and each row being offset to the adjacent rows. Even in such an automatic apparatus, however, the vendor is normally required to interrupt the automatic operation to make sample weighings to check if the quantity of slices has the proper weight. Each time the operation is interrupted valuable time is lost and the array of slices on the support table is not usually replaced in the exact position for production of an attractive and uniform array.

Another machine is known which produces a succession of slices all of approximately the same volume. This machine has a pair of feelers, one of which measures the diameter of the foodstuff--sausage, cheese, meat--and the other of which measures the thickness of the slices. The machine is set up automatically to increase the thickness when the width or diameter decreases and vice versa. Such a machine can, therefore, be set up to produce a succession of slices of approximately uniform volume. Since the density, that is the ratio of mass to volume, of a given foodstuff in normally constant, the machine can therefore produce slices of approximately uniform weight so that a given number of slices can normally be expected to have a given weight. The disadvantage of such a machine, however, is that slices of nonuniform thickness are produced which often render them wholly unusable for various purposes, such as sandwich making.

Other prior-art arrangements can be seen in Austrian Pat. Nos. 324,974 and 328,317, in Swiss Pat. Nos. 326,939 and 376,381, and in U.S. Pat. Nos. 3,142,323 and 3,220,498.

It is therefore an object of the present invention to provide an improved method of and apparatus for slicing and measuring a foodstuff.

Another object of this invention is to provide a slicing and measuring system which allows the total weight of the slices cut to be determined at any time during the slicing operation.

Yet another object is to provide such an arrangement which allows continual monitoring of the aggregate weight of the slices in a particular sequence even in combination with a depositing machine such as described in my above-cited copending applications Ser. Nos. 901,710 and 911,290

These objects are attained according to the instant invention in a slice-measuring method comprising the steps of supporting a foodstuff to be sliced on a table adjacent a blade and relatively displacing the table and the blade in a predetermined stroke direction past each other to cut a slice from the foodstuff. An output is generated when the blade engages into and cuts the foodstuff and the relative position of the table and blade is continuosly monitored. The monitored relative position is signaled on generation of the output indicating contact of the blade with the foodstuff being sliced.

This method therefore determines the width of the slice measured generally in the plane of the slice. Determination of the surface area therefrom is a relatively easy matter, simply by squaring the width if the foodstuff is squre or by squaring the width and then multiplying it times a factor equal to .pi./4. The resultant product is equal to the surface area which can be multiplied by the thickness to obtain the volume. Since the typical foodstuff handled by this invention--sausage, cheese, or the like--has a uniform density it is possible thereafter to multiply this volume by the density to determine the weight of the slice.

The slicing machine can be set up according to this invention to determine the weight of each slice in the manner described above and to add all of the thus determined weights in a given sequence to ascertain the overall weight of a plurality of slices. These determined weights can be displayed so that if the butcher is, for instance, asked for a quarter pound of thinly sliced roast beef, he need merely set the slicing machine to product thin slices, and then stop the slicing operation when the display for aggregate weight indicates a quarter pound. In practice it has been found that the method according to the present invention extremely closely approximates the actual weight of the material being sliced.

Another advantage of this invention is that the foodstuff being sliced, in particular in sandwich-making or other contexts where the exact weight is not absolutely critical, can be deposited by the slicing machine directly into the hand of the vendor, onto a piece of bread, or onto a platter. Thus even a relatively unskilled person can, for instance, prepare a sandwich using a relatively accurately determined quantity of meat or can prepare a buffet platter wherein, once again, the quantities of foodstuffs used are closely controlled.

According to further features of the instant invention, the slicer has a blade which is continuously rotated by an electric motor. The foodstuff being sliced is supported on a table adjacent the blade and is associated with automatic means with periodically displace the table past the cutting edge of the blade and which also step or index the table perpendicular to the slicing direction between each slicing operation. This table is connected to the wiper of a potentiometer. Furthermore a current or speed sensor is associated with the motor. As the cutting edge bites into the foodstuff the blade will be slowed or loaded slightly. The extra loading during the cutting operation as compared to when the blade is free running can be seen by the current detector as an increase in current consumption, whereas a speed detector can simply determine that the blade has slowed down somewhat. A pulse produced by this detector when it ascertains that the blade has contacted the foodstuff being sliced can be fed through the potentiometer connected to the table to produce a width signal pulse having a height directly proportional to the diameter of radius of the slice. Thereafter in accordance with the above-described mathematical operations, which can be carried out in very simple matter electronically, the weight of the slices is determined.

It is also possible in accordance with this system to link the above-described system with an automatic depositing device. In such an arrangement the depositing apparatus is arranged between the slicing blade and a table. Means is provided for arraying the separate slices in a plurality of rows, with the slices being offset in each row by a predetermined first distance and the rows being offset from each other by a predetermined second distance. The above-mentioned width-signal pulse is used to establish these two offset distances for production of an array wherein the overlap of slice to slice and of row to row is calculated in accordance with slice size.

The sole FIGURE of the drawing is a schematic view of the system according to this invention.

As shown in the drawing a table 1 reciprocal in a horizontal direction A carries a cylindrical sausage 2 elongated horizontally in a direction perpendicular to direction A. A circular cutting blade 3 has a cutting edge 3a and is driven by an electric motor 4 connected via a current sensor 5 to a source 15 of electrical power, here line voltage.

The table 1 is connected to the wiper 6 of a potentiometer 7 of the slide type. This wiper 6 is connected to the current detector 5 which is set up to generate a pulse of a predetermined height whenever the motor 4 is loaded and its current consumption increases. The potentiometer is set up so that its resistance will be directly proportional to the relative position of the table 1 and blade 3, in this case as the table 1 approaches the blade 3 the resistance of the potentiometer will increase.

The potentiometer 7 is further connected to a multiplying circuit 9 which takes the incoming signal that corresponds to the pulse generated by the detector 5 attenuated by the resistance of the potentiometer 7 and multiplied by a factor of .pi./4 and by another factor h equal to the thickness of the slice and fed in by a setable input device 8. The output of the multiplying stage 9 is fed to another multiplying stage 10 wherein the product produced by the multiplier 9, which is substantially equal to the volume of the slice being produced, is multiplied by a factor .rho. equal to the density of the foodstuff being sliced. This factor .rho. is fed in from an input keyboard 11 and is determined by the type of foodstuff. It is also possible to derive this factor .rho. from a memory 12 which knows the density for each foodstuff and is capable of feeding to the multiplier 10 the proper factor .rho. for the foodstuff being cut.

Finally the product produced by the multiplier 10 is fed to an adder 13 where a sum .SIGMA. is produced that is displayed on an alphanumeric readout 14. Thus as slices are cut off the foodstuff 1 the display 4 will indicate the total weight of slices produced.