BE1016647A3 - MACHINE CUTTING A BREAD. - Google Patents

Abstract

A bread slicer (1) comprises an introduction chute (4) of a loaf of bread intended to be cut, an outlet chute (5) releasing the cut slices and a cutting device (7) arranged between the chute introduction (4) and the outlet chute (5). The cut slices are arranged so as to reconstitute the loaf and are each supported by their lower edge on the bottom (6) of the outlet chute (5). The cutting device (7) has a circular knife (8) which engages transversely in the loaf of bread with less than half of the area of its cross section only. The loaf of bread is conveyed to the cutting device (7) by means of an advancing device (14) and a slice clamp (19), movable in the direction of advance (15), keeps the slices upright on their song. In order to obtain, even in the absence of knife oiling, an exact reconstitution of the loaf from the cut slices, the invention proposes that the circular knife (8) comprises first of all in longitudinal section, on the face facing the cut slices,

Description

The invention relates to a bread slicer with a chute for introducing a loaf of bread intended to be cut, with an outlet chute releasing the cut slices, arranged so as to reconstitute the loaf and to be in position. supported by their lower edge on the bottom of the outlet trough, and with a cutting device disposed between the goulotted'introduction and the outlet chute, said cutting device comprising a couteauxcirculaire which transversely engages in the loaf of bread with less only half of its cross-sectional area, the loaf of bread being capable of being conveyed to the cutting device by means of a feed device, a slicing clamp, movable in the direction of travel, allowing to keep the slices standing on their edge, the circular knife having first in longitudinal section, on the facetournée towards the cut slices, a z a bevel that begins from a sharp edge and is extended, adjacent to a vertex, an area that is set back from it and that extends further towards the axis of rotation than the transversal section of the introduction chute.

A bread slicer of the kind as mentioned above but which is suitable for use only and where the loaf of bread is greater than half the diameter of the circular cutter so that the bread also covers the area of the axis of bread. Knife rotation is known from German 1 022 768. By manual use, the problems related to the fact that slices being cut remain stuck do not occur. Untrancheur with a device in the form of annular segment mounted on a circular knife anddine to divert the cut product is also known from the publication JP 2001-29004.

A similar bread slicer is, for example, known from the prospectus "Bread slicer KM 38- The circular knife slicer for all types of bread" from Rosen & Robbert / Treif Group. In the case of this past bread slicer, the circular knife has aniameter allowing it to cover with less than half the knife the entire cross section of the introduction chute. When the circular knife is moving on a circular path, the axis of rotation of the circular knife thus remains always outside and particularly, in this case, below the introduction chute whose bottom is slightly inclined relative to horizontally. While at the moment when it enters the introduction chute the circular knife makes a movement directed both upward and to the side, this movement goes down and the side as soon as the cutting edge of the cutter has completely crossed the cross section of the introduction chute. The point of the curve described by the movement of the knife which has at this point only a component parallel to the bottom of the introduction chute is thus reached approximately at the center of the introduction chute. The rotational movement of the circular knife around the axis of rotation is oriented so that the loaf of bread is pressed against the bottom of the feed chute by the forces acting on it during cutting.

In order to avoid that the cutting surfaces of the bread, such as slices being cut, adhere excessively to the opposite side faces of the circular knife, the cutter is coated on the one hand with a Teflon layer serving as the non-stick coating. The prior bread wiper is also provided with an automatic lubricating device for coating the side faces of the circular knife with oil from a reservoir to effectively reduce the coefficient of friction.

The film of oil on the side faces of the knife has the disadvantage that the bread crumbs of the cut remain stuck there and that is thus formed a mixture of oil and half which with time takes the consistency of a viscous or sticky mass. At regular intervals, this mass is detached from the knife and accumulates in the grooves and partially inaccessible parts of the cutting device. This greatly complicates the cleaning of the anterior slicer; in addition, there are hygienic problems related to the fact that after a while this mixture of oil and crumbs, if not removed, is an ideal medium for the development of microorganisms, including mold. Particularly in the context of the recently reinforced hygiene rules, the risk of mold development unacceptably affects the quality of bread slicer of this type.

Moreover, it is not uncommon for the prior machine to present problems related to the arrangement of cut slices in the form of a reconstituted loaf, despite the use of oil during cutting. Due to the friction forces which, although reduced, still exist between the lateral face of the knife and the cutting face of the slice which has just been cut, a newly cut slice is unwanted and more particularly regularly staggered laterally in the instant following its severing, this decay takes place at a loaf reconstituted from cut slices whose surface has an irregular contour since the slices are offset with respect to each other. This sometimes causes complications when packaging such loaf reconstituted from slices in a plastic bag, this packaging being done manually by the operator of the bread slicer after cutting before returning the loaf of bread cut to the client.

The object of the present invention is to provide a bread slicer characterized by a good cutting quality without the use of oil during cutting and by a great geometric accuracy of the loaf reconstituted from the slices cut to avoid difficulties during its packaging.

In view of the bread slicer of the kind as mentioned in the preamble, this object is achieved in accordance with the invention in that the bottom of the outlet chute and the side wall of the outlet chute turned towards the end of the cut slice which the last is detached from the lamiche are each inclined relative to the bottom of the introduction chute and relative to the corresponding side wall of the introduction chute so that the slices are likely to be deposited in the outlet chute retaining an orientation identical to that they present when they are deviated from the cutting plane by the angles of beeeuffectives of the circular knife during their cutting.

The invention is based on the premise that it is possible on the one hand to effectively prevent the transmission of friction forces from the lateral face of the circular knife to the slices which have just been cut off by providing that the lateral face is placed set back from its top, ie relative to the point where the thickness of the knife reaches its maximum relative to its plane passing through the cutting edge. As a result, the slices, which are deflected by the bevel angle in the area behind the cutting edge, lose contact with the side face of the knife in the area behind the top, i.e. in the area set back from the first. In this way it is possible to avoid as much as possible that the friction forces are applied to a large surface of the cut slices, and so that the slices do not move transversely relative to each other in an untimely manner. The bread slicer of the invention thus makes it possible to obtain a cheese made from cut slices having a very high geometrical accuracy so that packaging problems, in a roll, for example, do not occur. The reduction of the friction forces transmitted by the lateral face of the knife obtained by the zone which, according to the invention, is set back makes even the lubrication of the facelateral of the knife superfluous. The slicer according to the invention thus makes it possible to satisfy the most stringent requirements in terms of hygiene. In particular, with the bread slicer of the invention, it is no longer possible for molds to develop from remains of viscous mass which are difficult to remove and consist of a mixture of oil and crumbs, since, since the crumbs remain dry, they are are more likely to stick to the slicer's parts and can therefore be easily removed. Moreover, the fact of giving up a degreasing device simplifies the construction which results in a reduction in manufacturing costs on the one hand and operating costs on the other hand (since no more oil).

The second substantial aspect for achieving the object of the invention is as follows: the bottom of the outlet trough and the side wall of the exit trough turned towards the end of the cut slice which is the last removed from the loaf are each inclined relative to the bottom of the introduction chute and relative to the corresponding side wall of the feed chute such that the slices are likely to be deposited in the outlet chute maintaining an orientation identical to that they present when they are deviated from the cutting plane by the effective bevel angle of the circular knife.

According to such a design, the geometry of the bottom and of the side wall of the outlet chute, against which the set of cut slices rests, has an orientation such that, especially if the previously cut slices have already been assembled before it, the slice which is being cut is not pushed against the side face of the knife which could cause the risk of a transmission of friction forces and thus the decaltransversal slices. The effective bevel angle of the knife is determined by the bevel angle determined geometrically and measurable with the circular knife as well as by the ratio between the component of the translational movement of the circular knife along the curvature that it describes and the component the rotational movement of the circular knife generated by its rotational movement about its axis. The component of the rotational movement is typically 10 times greater than the component of the translational movement of the cut so that one gets at the height of the end of bread cut last and especially when the cutting edge makes a downward movement in the direction of the chute bottom, an effective bevel angle which is mainly directed towards the bottom of the outlet neck and to a lesser extent only towards the side wall in support against the set of slices.

In one embodiment of the invention it is proposed that, in the recessed area, the lateral face of the knife makes, from the top, an angle of between 2 ° and 4 ° with respect to the cutting plane before being parallel to this one.

Another possibility to replace such a continuous transition between the top and a zone set back at a constant distance from the cutting plane of the circular knife is to provide, from the top, between the lateral face of the knife and the recessed area, recess substantially perpendicular to the plane of the knife, the recessed area being parallel to the cutting plane.

Such stepped recess is particularly easy to achieve if, according to a preferred embodiment, the knife is provided on its side facing the cut slices, a ring fixedly secured to the rest of the knife, the top being disposed in the longitudinal cut of the axel between the beveled zone and the recessed zone.

A ring of this type, connected in the form of an additional piece to the basic body of the knife, makes it possible to avoid the use of a machining technique for removing the chips to make the recessed area, this machining technique 'not being the simplest.

The ring, which may for example also be made of a special steel and be coated with a non-stick coating, Teflon® for example, is preferably attached to the rest of the paring knife.

To further minimize the frictional forces between the circular knife and the product to be cut, the invention proposes that the face of the knife which is turned towards the loaf of bread also comprises in longitudinal section a recessed area adjoining a bevel zone which is extends from the sharp edge. This arrangement makes it possible to obtain a particularly smooth cut and to reduce the required driving power since the swaging forces are only applied on the area bordering the knife.

An improvement of the idea according to the invention provides that the bottom of the outlet chute and the side wall of the outlet chute facing the end of the cut slices which sedétache last of the loaf are each parallel to the perpendicular surface from the plantangent to the effectively beveled face of the circular knife that extends from the cutting edge, the tangent plane being constructed at a point on the sharp edge where a slice is last removed from the loaf of bread.

Once again, the effective beveled face is defined so that the beveled face obtained first of all by the simple geometry of the circular knife is reoriented according to the velocity vector resulting from the circumferential speed of the circular knife during its rotation movement around it of its axis and the translational movement of the circularcircuit along the curve described by its center.

It has finally proved particularly advantageous that the angle that the bottom of the introduction chute with the bottom of the outlet chute in a cross section perpendicular to two funds is between 8 ° and 12 °, but preferably is an angle by 10 °, and a side wall of the introduction chute and a side wall of the outlet chute controls which respectively abut the loaf of bread to be cut and the set of cut slices are inclined at an angle included between 2 ° and 4 °, preferably one anglede 3 °, one relative to the other. In this case, the ideal conditions for placement of the cut slices are obtained, especially if the ratio between the circumferential speed of the circular cutter and the speed of translation of the circular knife along its path is between about 7: 1 and 10: 1 and if the trajectory of the knife is a circle whose center is slightly offset relative to a median plane perpendicular to the bottom of the introduction chute so as to deviate from the side wall against which is supported when grinding the loaf bread to cut .

The invention will be better understood on reading the description which will be made of an embodiment of a bread slicer given by way of example and illustrated in the drawing. The figures show: FIG. 1 is a side view of a bread slicer, FIG. 1 is a top perspective view of the exit chute of a bread slicer of FIG. 1, FIG. 2 is a view of the circular knife of the slicer. FIG. 3 is a sectional view along the line III-III of the circular knife of FIG. 2; FIG. 4 is a detail on a larger scale of the view illustrated in FIG. 3; FIG. similar view to that of Figure 1 with a view of the outlet chute, Figure 6 a sectional view along the line VI-VI bread slicer of Figure 5, Figure 7 a sectional view along the line VII- VII of the bread slicer of Figure 5.

A bread slicer 1 has a machine housing 3 which is movably mounted on four rollers 2 and in which are located one behind the other an introduction chute 4 for a bread mill to be cut and an outlet chute 5 for cut slices forming reconstituted bread lamiche, said slices being placed on their edge in the bottom 6 of the outlet chute 5. The loaf of bread intended to be cut and the cut slices are not shown in detail in the drawing. The basic structure of a bread slicer 1 of this type is known from the prospectus "Bread slicer KM 38 - The bread slicer for all types of bread" of the company Rösen & Robbert / Treif Group for example. As appears more particularly in FIGS. 6 and 7, a cutting device 7 is located in a zone in between between the introduction chute 4 and the outlet chute 5, this cutting device comprising a circular knife 8 which turns from a It extends around its center 9 at a speed of 740 rpm and, on the other hand, along a circular path 10 a circumferential rotation at a speed of 135 rpm. The circular knife 8 rotates about its axis in the direction of the arrow 11 and the rotational movement of the circular knife 8 in its entirety along the path 10 is in the direction of the arrow 12, which is to say that the direction of these two rotational movements is the same.

The cross-section of the introduction chute visible in FIG. 1 is entirely covered by the movement made along the path 10 of the circular knife 8 from the position illustrated in FIG. 1 in which the circular knife 8 is just transversely engaged so that the slices of bread can be sensed entirely independently of the size of the loaf introduced into the goulotted'introduction 4. With the aid of a retaining member 13 of a feed device 14 , bread lamiche is conveyed to the cutting device 7 in the direction of advance (arrow15 in Figures 6 and 7). The retaining member 13 of the bread is adjustable across the direction of advance so that the loaf of bread placed therein can always be in contact with a side wall 16 of the introduction chute 4 and that it is plated against this side wall 16 by the circular knife 8 during cutting.

Figure 1 shows the bread slicer 1 in a position in which the outlet chute and the part of the associated casing have been spread by pivoting them on the hinges 17; those are not represented here. In this position, the cutting device 7, the goulotted'introduction 4 and the outlet chute 5 are accessible by their end faces turned towards each other for cleaning.

Figure la shows only the housing portion in which the outlet chute5 is located. A slice clamp 19 which is slidably movable in the direction of travel on a guide rod keeps the cut slices standing on their edge.

The housing portion provided with the outlet chute 5 further has a receiving plate 21 which is secured only in the region of a flange segment 20 which protrudes from the mamma of a tongue and is provided with a stop mounted movably in a groove 22 and not shown in the figures. The receiving plate 21 serves to deposit the set of cut slices removed by hand from the outlet chute to slip into a packaging bag.

As illustrated in FIGS. 2 to 4, the circular knife 8 is provided with a bevelled face 24 which extends from a slightly toothed cutting edge 23 and which forms with the opposite lateral face 25 a bevel angle a which is of the order of 10 ° in this case. While the side face 25 is facing the loaf of bread, the bevelled face 24 is placed in contact with the slice that is being cut or has just been cut. The bevelled face 24 is firstly formed, starting from the cutting edge 23, by a base body 26 of the circular cutout 8 itself and then by an adjoining ring 27 which, at the edge, is cut into a wedge at a bevel angle a 10 ° also and which is fixed by gluing to the base body 26 of the circular knife 8. The ring 27, like the base body 26 of the circular knife 8, are made of a special tempered steel and are provided with an anti-corrosion coating. Annealed teflon adhesive having a thickness in the range of about 50 to 70 microns.

Immediately after a vertex 28 of the circular knife 8 located at the height of the ring 27, the circular knife 8 comprises a recess 29 in step that extends a zone 30 located back from the top 28. In the region of this zone 30 locatedretretrait, the thickness of the circular knife 8 is reduced by about 40% relative to the thickness of the circular knife 8 in the region of the summit 28. The recessed area prevents the slices that are being cut or which have just been cut from contact with the lateral face of the circular knife 8 so that the risk of inadvertent lateral displacement of the slices due to the transmission of friction forces between the circular cut 8 and the slice of bread is reduced to a minimum. In this case, the recessed area 30 extends almost as far as a central bore 31 for supporting the circular bag 8. In all cases, however, the recessed area 30 should extend sufficiently radially inwardly so that even the largest slice that can be cut with the bread slicer 1 does not come to any place of the face of its transversal section in contact with the lateral face of the circular knife 8 which faces it.

Instead of providing, as illustrated by FIGS. 2 to 4, an embodiment with a recessed zone 30 created by a ring 27 fixed by gluing, it goes without saying that this zone 30 set back by employing a chip removal machining technique, for example by abrasive working, in a one-piece knife. Thus, another recessed zone 32 is obtained on the opposite lateral face 25 of the circular knife 8. This recessed zone 32, which must also reduce to a minimum the contact of the circular cutter 8 with the cut of the loaf, forms a recess whose depth corresponds to only Ά only of the depth of the recess 29 formed on the inner surface of the ring 27.

FIG. 6 shows that the bottom 6 of the outlet chute 5 is inclined at an angle β of 10 ° to the bottom with respect to the direction of advance 15 which is parallel to the bottom 33 of the goulotted'introduction 4. In addition, the side wall 34 of the outlet trough 5 is rotated by an angle γ of 3 ° with respect to the side wall 35 of the introduction trough 4 (which is parallel to the forward direction 15). The aforesaid angles β and γ are obtained from the angle of bevel ade 10 ° (purely geometrical) of the circular knife 8 and the ratio between the circumferential speed of the circular knife 8 in the region of the cutting edge 23 and the transmission speed circular knife 8 along the trajectory 10, the two aforementioned speeds being taken into account at the precise moment when a slice detaches from the loaf, that is to say. approximately when the cutting edge 23 of the circular knife 8 reaches the inner edge 36 (see Figure 1) of the introduction chute 4 in the transition zone between its bottom 37 and paroilateral 16. The two aforementioned speeds are to be added vectorially at the speed of the knife obtained at the time of sectioning; the actual orientation in the space of the bevel angle α of the circular knife 8 is thus obtained. The angles β and γ made between the goulotted'introduction 4 and the outlet chute 5 make the angle at which the Sliced slices that have just been cut off effectively prevent them from bending over the lateral face of the circular knife 8 facing them.

By combining the particular design of the circular knife 8 with the area 30 inretrait and with the orientation of the outlet chute 5 which is inclined in two directions relative to the introduction chute, the conditions under which the cut slices are deposited that it is possible, even if one renounces oiling the coutnecirculaire, to obtain a set of cut slices reconstituting the shape of the micheinitiale with a great geometric accuracy as a result of the minimization of the friction forces.

Claims (8)

1. Bread slicer (1) with an introduction chute (4) of a loaf of bread to be cut, with an outlet chute (5) releasing the cut slices, arranged so as to reconstitute the loaf and to be in position. supported by their lower edge on the bottom (6) of the outlet trough (5), and with a cutting device (7) arranged between the insertion chute (4) and the outlet trough (5), said device comprising a circular knife (8) which engages transversely in the loaf of bread with less than half of the area of its cross-section only, the loaf being able to be conveyed to the cutting device (7) by means of of a device for advancement (14), a slicer (19), movable in the direction of advance (15), for keeping the slices upright on their edge, the circular cutter (8) comprising first in section longitudinal, on the facetournée towards slices cut s, a beveled area (24) which starts from a cutting edge (23) and is extended, adjacent to a top (28), a zone (30) which is set back from it and which extends further towards the axis of rotation than the cross-section of the introduction trough (4), characterized in that the bottom (6) of the outlet trough (5) and the side wall (16) the outlet trough (5) facing the end of the cut slices which is last removed from the loaf are each inclined relative to the bottom (36) of the feed chute (4) and relative to the side wall (35). ) corresponding to the introduction chute (4) so that the slices are likely to be deposited in the outlet chute (5) maintaining an orientation identical to that they have when they are deviated from the cutting plane by the chamfer angle of the circular knife (8) when dry tioning. Bread slicer according to claim 1, characterized in that, in the recessed area (30), the lateral face of the circular knife (8) makes an angle of between 2 ° and 2 ° from the apex (28). 4 ° with respect to the cutting plane before being parallel thereto. 3. Bread slicer according to claim 1, characterized in that, from the end (28), between the lateral face of the circular knife (8) and the zone (30) located in a recess, a recess (29) substantially perpendicular to the cutting plane, the recessed zone being parallel to the cutting plane. 4. Bread slicer according to any one of claims 1 to 3, characterized in that the circular knife (8) is provided on its side facing the cut slices, a ring (27) firmly fixed to the rest of the knife, the apex (28) being disposed in the longitudinal section of the ring between the beveled zone (24) and the recessed zone (30). 5. Bread slicer according to claim 1, characterized in that the ring (27) is fixed to the remainder of the circular knife (8) by gluing. 6. Bread slicer according to any one of claims 1 to 5, characterized in that the face of the circular knife (8) which is turned towards the loaf of bread also comprises in longitudinal section a recessed area (32) adjacent to a zone Bevel extending from the cutting edge (23). Bread slicer according to claim 6, characterized in that the bottom (6) of the outlet chute (5) and the side wall (34) of the outlet chute (5) facing towards the end of the cut slices which are The last tangent of the loaf is eachparallel to the perpendicular surface of the plane tangent to the effective beveled face of the circular knife (8) extending from the cutting edge (23), the tangenting plane constructed at a point of the sharp edge (23) where a slice breaks endernier loaf of bread. 8. Bread slicer according to claim 6 or 7, characterized in that an angle a between the bottom (6) of the outlet chute (5) and the bottom (33) of the feed chute (4) is included between 8 ° and 12 ° but preferably is an angle of 10 ° and an angle γ between a side wall (34) of the outlet trough (5) and a side wall (36) of the introduction trough (4) is between 2 ° and 4 °, but preferably is a 3 ° angled.