WO2014162226A1

WO2014162226A1 - Compact unit for meat processing, with elastically yieldable grinding and mincing knives

Info

Publication number: WO2014162226A1
Application number: PCT/IB2014/059936
Authority: WO
Inventors: Marcello Quadrana
Original assignee: Evolution S.R.L.
Priority date: 2013-04-03
Filing date: 2014-03-18
Publication date: 2014-10-09
Also published as: ITRM20130197A1

Abstract

Unit for grinding/mincing (100; 100') a food substance, mountable (or rigidly provided) on an outlet (18) of a machine of a line for loading and supplying the food substance itself, such unit (100; 100') comprising various grinding stages whose elastically yieldable knives (6; 6a; 6b; 6c; 6d) interact with respective sieving collar areas (8) obtained on a stationary sieving means (7). The through holes (9) of the sieving collar areas (8) have diameters decreasing from a preceding stage to the next one. The elastically yieldable knives (6; 6a; 6b; 6c; 6d) are radially mounted on a rotary thrust and cutting body (4) coaxial with a stationary external jacket (1) for containing the stationary sieving means (7). The elasticity of the knives can be obtained with a notch (14) and/or by providing elastic means for mounting the knives on the rotary thrust and cutting body (4).

Description

"Compact unit for meat processing, with elastically yieldable grinding and mincing knives"

Description Field of the art

The present invention refers to the field of processing a food substance which presents itself in the shape of a more or less continuous mass to be ground, and more specifically it regards a complex or unit to be mounted on a machine for supplying pieces of meat which form a more or less continuous mass and which are supplied by an auger arranged upstream of the unit according to the present invention. In particular, the continuous mass of food substance could be the meat (for example pork meat) for producing sausage (e.g. mortadella). Upstream of the unit according to the present invention, a finisher/rougher could be used in order to render the meat more uniform before it reaches the grinding and mincing unit according to the present invention.

Prior art

Known in the art are systems for mincing, i.e. chopping, food substances and particularly meat.

Such treatment of the meat (e.g. pork) is carried out in processing lines installed in sterile environments at controlled temperature (usually about 16 degrees centigrade). The pieces of meat (having a temperature of about -4°C) pass through units which progressively reduce the size thereof, mincing them and forming an increasingly uniform mass; in particular, said pieces of meat first cross through finishers before then reaching a final unit, like that which is the subject of the present invention.

Such unit can be of various types.

Normally, as mincing unit, a pack of perforated and stationary circular discs is used; these are alternated in the unit itself with radial knives which, by scraping the surface of the perforated discs, produce a guillotine-cutting effect on the meat (pushed by suitable means such as an auger or the like). The meat, or another food substance to be minced, is chopped into increasingly smaller particles in accordance with the decreasing size of the holes present in the various perforated circular discs of the processing unit.

However, there are various drawbacks that can be attributed to this type of grinding unit:

- the grinding unit has considerable and non-constant load loss (gradient) through the discs, especially by virtue of the fact that the discs with small holes have an overall surface of the holes (total area for the passage of the food substance) clearly lower than that of the discs with holes of larger diameter (even if the holes are less numerous); hence, given that the diameter of the flat circular discs is substantially identical for all the discs, the force necessary to make the meat pass through the discs is not the same, but rather it tends to increase towards the outlet of the grinding unit, and from this it is clear that more power is absorbed for working the meat;

- the grinding unit could be made more compact; this is important since it preferably constitutes a "module" to be mounted on the outlet of the machine of the meat processing line which comprises one or more loading hoppers, the supply channels, and the finishers, in addition to the augers which feed the meat itself towards the outlet (where the final grinding unit is situated); a more compact module would be easier to handle, transport, disassemble and reassemble, at the end of the daily production, for preserving it in a refrigerator at low temperature, so as to prevent the necessary operations of disassembly of the single components and cleaning adapted to prevent bacteria proliferation in the residual meat that remains attached; this would in fact be inadmissible, since during the subsequent work shift the bacteria would be mixed with the produced fresh meat;

in the central part of the discs, there is a lower passage of meat, since clearly the various knife-holder arms converge towards the hub, and in addition there are less holes at the center of the discs themselves; moreover, in the central zone, the linear rotation speed of the knives is lower; all this leads to a non-uniform passage of the meat, to a lower lubrication at the center of the disc, and hence to a progressive convexity of the disc that by rubbing - over time, against the knives - gives rise to micro-welds; the subsequent separation of these micro-welds causes the unintentional and damaging addition of metallic microparticles in the food substance to be ground/minced; hence, the load is not well distributed not only among the various perforated discs, but also among the various zones of a same perforated disc.

In the patent US 7,389,954 Bl (granted to Marcello Quadrana on 24 June 2008), several of the abovementioned problems were brilliantly resolved by employing a completely different type of grinding unit, with respect to that with flat perforated discs and linear/axial passage of the meat. The present invention takes this solution of the abovementioned US patent as a starting point, but it resolves another technical problem that was not taken under consideration by the preceding solution. The patent US 7,389,954 Bl must in any case be considered incorporated in the present description for any reference and specification that may be useful for the reader.

Indeed, also in this solution of the prior art, described in the abovementioned United States patent, the problem of the micro-welds could arise due to the rubbing, to the seizure, to the friction heat (under the effect of the considerable pressure of the meat) of the blades of the knives (8) against the sieving means (6), which constitute holes (10) distributed on a cylindrical element (6) or approximately conical element (6) [the numbers between the parentheses are those of the patent US 7,389,954 Bl].

Object of the present invention is the introduction of particular knives (elements with blade) that allow remedying the problems of the micro-welds, without however giving up the advantages brought by the new technology of the patent US 7,389,954 Bl, i.e. a greater compactness of the grinding unit, a greater energy efficiency (ratio between the product quantity and the absorbed energy), and a uniform distribution of the load (and hence already a reduction of the incidence of failures and problems of the production line).

Brief description of the drawings The present invention will now be described as merely exemplifying with reference to particular embodiments thereof shown in the drawings, in which:

FIGURE 1 is half axial section C-C (see Fig. 3) of the grinding unit with cylindrical form of the present invention;

FIGURE 2 shows, in a very schematic manner, the inventive concept that underlies the present invention; FIGURE 3 is a side view of the grinding unit with cylindrical form of the present invention;

FIGURES 4A and 4B are cross sections A-A and B-B, respectively, executed in different axial positions and referred to the embodiment of Fig. 3 of the machine of the present invention;

FIGURE 5 shows a second grinding unit (now conical) according to the present invention, flanged and flange-coupled to a tubular part of the machine for supplying the meat (already finished) or another food substance to be chopped; FIGURES 6A, 6B and 6C are cross section views in the planes B-B, C-C and D-D of Fig. 5, executed in various axial positions of the conical grinding unit according to the second embodiment of the invention;

FIGURE 7 is a partial side view, partial sectional view, and with tears, in order to see the various annular perforated elements of the stationary sieving means (with holes of progressively decreasing diameter); it is observed that the knives were not drawn in this figure 7 in order to simplify the drawing. Detailed description of the invention

With reference to Fig. 1 and Fig. 3, the unit 100 of the present invention, in this particular embodiment, comprises a substantially cylindrical and stationary external jacket 1, bearing on its internal surface a plurality of convex annular recesses 2, separated from each other by annular ribs 3, the number of such annular recesses 2 and such annular ribs 3 of the external jacket 1 being variable according to the circumstances, i.e. according to the requested processing stages (nature of the food substance, etc.). The annular recesses 2 do not form sharp edges, i.e. they have a curvature that varies gently without singularities, in a manner so as to facilitate the passage of the food substance that crosses through the space defined by such recesses 2. Inserted in the jacket 1 is a rotary thrust and cutting body 4 which could also be composed of single elements 4a, 4b, 4c, 4d, etc., integrally connected to each other in order to be able to rotate simultaneously together with respective blades 6a, 6b, 6c, 6d, etc., which are rigidly connected to the rotary thrust body. Hence, the rotary thrust and cutting body 4 rotates around the geometric axis "X-X", see Fig. 3, during the operation of the unit, while a cylindrical stationary sieving means 7 is extended along the entire external jacket 1 and is fixed inside the latter (preferably in a removable manner), and in any case is stationary. Specifically, the sieving element 7 is directly in contact with the annular ribs 3 at the respective points visible in Fig. 1. The sieving element 7 constitutes a tubular body, i.e. cylindrical, e.g. made of food-grade steel like substantially the entire unit 100, subject of the present invention. The section C-C of Fig. 1 of course constitutes only half of the section executed in the homonymous plane of Fig. 3; in other words, it must be intended duplicated/mirrored symmetrically under the axis X-X of Fig. 1. On the sieving element 7, various circular collar area zones 8 are provided, separated from each other by slots 10, each circular collar area 8 having a plurality of tilted holes 9 for facilitating the passage of the meat. To be precise, in each respective axial position of the unit 100, various slots 10 are equally distributed in a circle on the sieving element 7, all around the rotary thrust and cutting body 4. Analogously, various curved blades 6a (or 6b, or 6c, or 6d) are arranged all around the rotary thrust body 4 and are integral therewith within annular grooves or cavities 11, in the respective axial position of the mincing unit 100. This is inferred, for example, from figures 4A and 4B, in cross section, in which for the sake of simplicity only some of the blades 6a (or 6b) have been expressly indicated by their numeric reference numbers 6a (or 6b).

The above discussion in substance constitutes the prior art of the abovementioned United States patent, and for further clarifications reference is made to the relative description.

During operation, i.e. rotation round the axis X-X of the rotary thrust and cutting body 4, the meat (or generally a food substance to be minced) crosses the grinding unit 100 from right to left (in Fig. 1), following a zigzag path, specifically:

- it first reaches (pushed by an auger of the machine) the annular cavity 11 situated more to the right in Fig. 1;

- then it passes through the tilted holes 9 of larger size, being pushed by the blades 6d;

- then, after the entrance into the first annular recess 2, it crosses through the slots 10 (towards "the bottom" in Fig. 1);

- then it reaches the subsequent annular cavity 11 ;

- then, pushed by the subsequent blades 6c, it crosses through the next tilted holes 9 (generally smaller than the first), reaching the subsequent annular recess 2 of the external jacket 1;

etc. etc. until it exits from the unit 100 though (for example) the radial hole 13.

It is observed that the tilt of the holes 9 is such to facilitate the passage of the meat under the thrust of the auger of the machine placed upstream (not shown) and the blades (suitably shaped) of the rotary thrust and cutting body 4.

It is observed that the auger could also not be integral with the rotary thrust body 4; in this case, the two components could independently rotate and their speed could be independently controlled. For example, the element 12 of Fig. 3 could serve as a rotation shaft (moved by autonomous motor) of the rotary thrust and cutting body 4, which would then be decoupled from the auger (not shown) for supplying the food substance. Finally, the food substance is drawn from an outlet of the unit 100, for example from the radial opening indicated with 13 in Fig. 1.

All this constitutes, in substance, part of the prior art (abovementioned United States patent), and does not properly regard the present invention.

Now, according to the present invention, with reference to the very schematic figure 2, a generic curved blade "6i" arranged in a generic annular cavity 11 has a longitudinal incision 14. Such longitudinal incision 14 is extended in the extension direction of the blade 6i, which - as always - is extended between two respective ribs 3' of the rotary thrust body 4; in the drawing, only one blade portion 6i and a part of the incision 14 are shown, the dashed lines 15 and 16 indicating that the blade 6i is in reality extended from one end of the annular groove 11 to the other.

The incision 14 "removes" a certain distance/measure from the normal thickness of the blade 6i, and hence the blade 6i becomes elastically yieldable. The upper edge 17 of the blade 6i is in sliding contact with the respective circular collar area 8 (not shown in Fig. 2) bearing the tilted holes 9 for the passage of the food substance.

In addition, according to the present invention, preferably a material such as silicone or the like fills the longitudinal incision 14 in a manner so as to prevent deposits (crusts) of food substance, which over time would nullify the elastic pliability effect of the blade 6i due to the longitudinal incision 14.

According to the present invention, preferably all the blades 6a, 6b, 6c, 6d are elastically yieldable.

This allows the blades to prevent seizure and the consequent micro-welds on the perforated collar areas 8, against which the blades themselves slide in order to cut meat or the like "like a guillotine", mincing it.

The effect of pressure applied by the meat will thus have more difficulty in causing the seizure of the blades against the sieving element 7, since the blades 6 themselves are elastically yieldable. Other systems could be employed for obtaining the elastic pliability of the blades 6, for example by mounting them directly by means of elastically yieldable means on the rotary body 4.

Thus, the present invention is not limited to the specific embodiment of Fig. 2 but rather is extended to any type of blade 6 equipped with means that render it elastically yieldable to the possible convexities of the stationary sieving means 7, thus limiting the rubbing (and the consequent micro-welding of the metal) between these components 6 and 7 in relative rotation.

With regard to figures 5, 6 and 7, these refer to a unit for grinding or mincing 100' with substantially conical form.

A similar embodiment is also comprised in the abovementioned United States patent.

In this case, the final tubular part 18 of the machine for supplying the food substance is couplable, by means of a flange 19b, to the flange 19a of the frustoconical unit 100' of the second embodiment of the present invention. The shaft 12 as usual constitutes a rotation and centering member for the rotary thrust and cutting body 4 inside the external jacket 1. As is inferred from Fig. 7, the diameters of the sieving holes 9 are progressively decreasing in the direction of the arrow F (direction of passage of the meat or the like), from one collar area 8 to the next. This solution has the following advantages, with respect to the preceding:

- the slots 10 ensure a practically rectilinear (axial) passage of the food substance among the various mincing stages, thus reducing the force employed and thus the power (increase of efficiency);

- the progressive increase of the radius of the circumference of the perforated collar area 8 in the direction of the arrow F ensures that the total area of the holes 9 increases (with respect to the first embodiment of Fig. 1), since their number increases; this allows limiting the axial size of the unit 100' with respect to the unit

100, also taking under consideration the fact that with the decrease of the diameters of the holes 9, there is also the reduction of the "traversable surface", even with the greater number of holes (see above). Overall, these two advantages ensure that there is a constant load along the mincing path of the grinding unit 100' (thus preventing load peaks), even if limiting the axial size of the same unit. This signifies that less power is required for processing, and that there is a reduction in the number of repairs to be carried out, since the meat (or other item) slides more regularly through the grinding unit.

According to the present invention, moreover, the blades 6 of the knives sliding against the perforated collar areas 8 will be elastically yieldable, as in the first embodiment, and this will prevent (or in any case reduce) the number of the so-called micro-welds, according to which the pressure of the meat on the blades, as well as on the possible local convexities that are formed during operation in the areas 8 of the sieving means 7, causes the seizure and the welding of the blades 6 on the sieve 7 and the subsequent separation of metallic particles that come to be mixed with the finished product (= minced food substance).

Claims

1. Unit (100; 100') for grinding or mincing a food substance, in particular meat, comprising a substantially tubular-shaped stationary external jacket (1) delimiting an internal chamber (19a; 19b) and couplable to an outlet of an end part (18) of a machine for loading, supplying and processing the food substance, the unit (100; 100') further comprising a plurality of grinding stages, each being constituted by: a respective annular recess (2) formed on the internal surface of the stationary external jacket (1) and separated by homologous annular recesses (2) belonging to the other grinding stages;

an annular groove (11), provided facing each annular recess (2) on a rotary thrust and cutting body (4), the latter being mounted in said internal chamber for rotating coaxially with respect to said stationary external jacket (1), advancing the food substance along a mincing path;

- a respective sieving collar area (8), obtained on a stationary sieving means (7) and bearing respective through holes (9); wherein the stationary sieving means (7) is interposed between said rotary thrust and cutting body (4) and the stationary external jacket (1);

a plurality of slots (10) arranged along said mincing path and such to create a direct communication, substantially without hindrance, between one grinding stage and the subsequent one, between one side and the other of the stationary sieving means (7); said slots (10) being formed on the stationary sieving means (7) between one collar sieving area (8) and the subsequent one;

a plurality of blades (6; 6a or 6b or 6c or 6d), arranged around said rotary thrust and cutting body (4), and integral to the latter within the respective annular groove (11); said blades (6; 6a or 6b or 6c or 6d) being shaped, made and oriented so as to produce on the food substance a thrust and cutting effect against an internal surface of the stationary sieving means (7) during the rotation of the rotary thrust and cutting body (4);

wherein the diameters of the through holes (9) are overall decreasing between one grinding stage and the subsequent one, starting from an inlet towards an outlet of the grinding unit (100; 100'), in the direction defined by a geometric longitudinal axis X- X of the grinding unit along said mincing path, and the through holes (9) being provided in said collar sieving areas (8) with number and diameter such to create a substantially constant loading gradient between one side and the other of the stationary sieving means (7), in the various grinding stages;

the grinding and mincing unit (100; 100') being characterized in that the blades (6; 6a or 6b or 6c or 6d) are elastically yieldable, having an incision (14) which reduces the thickness thereof and/or being mounted on elastic means, or spring-equipped means, on said rotary thrust and cutting body (4).

Grinding or mincing unit (100; 100'), according to claim 1, characterized in that said incision (14) extends substantially from one side to the other of the blade (6; 6a or 6b or 6c or 6d), along the entire longitudinal extension of the blade.

Grinding or mincing unit (100; 100'), according to claim 1 or 2, characterized in that said incision (14) is filled with a soft sealant, for example silicone, which prevents the deposit and formation of crusts of food substance in the incision (14) over time.

Grinding or mincing unit (100'), according to any one of the preceding claims, characterized in that said stationary external jacket (1) is conical-shaped.

Grinding or mincing unit (100'), according to claim 4, characterized in that said stationary sieving means (7) forms a plurality of subsequent hollow cylinders each corresponding to one of said collar sieving areas (8), constituting steps with steeply tilted interruption areas in which there are obtained said slots (10), in which the diameter of said subsequent hollow cylinders increases in the direction of said mincing path.

6. Unit (100; 100') according to any one of the preceding claims, characterized in that said through holes (9) are tilted, being arranged directed towards the mincing path.

7. Unit (100; 100') according to any one of the preceding claims, characterized in that the rotation of said rotary thrust and cutting body (4) can be controlled independently from the rotation of an auger for supplying the food substance and/or in that the means for centering said rotary thrust and cutting body (4) in the stationary external jacket (1), are constituted by a shaft (12) disconnected from said auger for supplying the food substance.