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EP 1 574 304 A1 |
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EUROPEAN PATENT APPLICATION |
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Date of publication: |
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14.09.2005 Bulletin 2005/37 |
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Date of filing: 09.03.2004 |
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Designated Contracting States: |
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AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LI LU MC NL PL PT RO SE SI SK TR
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Designated Extension States: |
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AL LT LV MK |
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Applicant: Daub Holding B.V. |
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5051 HT Goirle (NL) |
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Inventors: |
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- Breugelmans, Marcus, Aloysius, Petrus, Theodorus
5051 HT Goirle (NL)
- van den Hamsvoort, Petrus, Wilhelmus, Johannes
5051 HT Goirle (NL)
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Remarks: |
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Amended claims in accordance with Rule 86 (2) EPC. |
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(54) |
Bread slicer with knives arranged in a wave- or v-shape. |
(57) The device for slicing loafs or breads and other mainly elongated objects into slices,
is constructed of two reciprocal oscillating supporting frames (6, 7) with in longitudinal
direction fixed knives (5', 5) on one side, which in top view are applied in layers
such as a wave- or V-shape to minimalize the compression of the bread with all its
advantages and in which the mentioned knives (5', 5) are sharpened on one side in
cross-section, in which in longitudinal direction the knives (5', 5) on the other
side slide through a light guiding frame (11), in which the mentioned supporting frames
(6, 7) move an eccentric mechanism (8) up and down or forth and back and the bread
is pushed through the knives (5', 5) by a pusher (3).
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[0001] The present invention relates to a device for cutting loafs and other mainly spacial
products into slices, mostly in order to offer the sliced bread packed to the client,
in which in the mentioned device specially constructed blades are mounted, in which
supporting and guiding plates or means for slicing loafs or breads have been applied,
in which the mentioned loaf or bread is moved with a pusher towards a number of oscillating
or moving cutting instruments with an approximate equal mutual distance and placed
transverse on the bread, in which the mentioned distances between the cutting instruments
is done in such a way to allow compression compensation, in which the movement or
the oscillating movement in the longitudinal axis of the mentioned cutting instrument
is done by means of a special driving mechanism, in which the whole is mostly provided
with a housing to protect the user, in which an intake and outlet opening is included.
[0002] A somewhat similar device is known e.g. from the American Patent document US 1 975
942, titled: "Bread Slicer", of HARTMAN, William, Walter, Los Angeles, California.
Patent is issued on 09-10-1934. Here, it concerns a cutting mechanism for bread slicers.
A cutting head consists of multiple lateral, at a distance placed knives in parallel
planes, in which at one side the knives are connected to a crankshaft and at the other
side are tensioned with draw springs in a rimmed stretcher, which must be constructed
rather heavily due to the many springs. The drawing springs on the top side of the
knives are suspended in a blunt V-shape, through which the knives start cutting the
bread practically at the same time, but first the outer knives and then step by step
inwardly the next pairs of knives are used, through which the bread is not pulled
apart. The mentioned V-shape is achieved singularly over the whole length of the loaf
or bread, through which the staggering of the knives, also due to the very blunt inner
angle, is very small and in which the knife staggering is not completely used. The
set-up of the knives shows an almost complete overlap, through which a high compression
is created on the loaf per slice. Actually the knives form half a cone and due to
the crankshaft only one cone with a very small top angle is possible. Due to the mentioned
crankshaft and the V-shaped set-up of the drawing springs, the thin knives will start
vibrating sooner and due to the tension of the springs of a large quantity of drawing
springs a lot of energy is necessary to keep the device going to cut through the loaf
or bread. Further, the exerted pressure of the pusher cannot be too high because the
knives almost simultaneously cut into the loaf or bread, through which the resistance
is large due to the cutting and the slices are crushed together. This is not beneficial
for a beautiful result of the sliced bread.
[0003] The above described solution for a bread slicer has a number of disadvantages, such
as the heavy frames, the relatively large driving power to move the knives with drawing
springs up and down and to move the compressed slices between the mutual overlapping
knives by means of friction and next also the driving power for the pusher, which
also leads to vibrations.
[0004] Further, research has shown that the set-up of the knives and the construction thereof
has a large influence on the compression of, for example, cutting a bread and has
further consequences, as shown hereafter.
[0005] In the known bread slicers the knives are mostly placed in almost an overlapping
row. The knives, which are tensioned with a spring load of approximately 200 to 400
N and depending on the make of the slicer, have a varied thickness of 0,4 en 0,5 mm,
an average of 0,45 mm, in which they are sharpened double sided. For the compression
of the bread with a length of 400 mm and a required slice thickness of approximately
10 mm, can be determined with a usual thickness of the knives of 0,45 mm, e.g. In
this case 400:10=40 knives with a thickness of 0,45 mm are active. Herewith, the whole
bread is forced to compress 40×0,45mm=18mm. This compression has friction as the most
important disadvantage, which develops between the knives and the bread due to the
applied compression forces. The consequences are:
- wear of the knives;
- crumbling;
- sticking of the bread on the knives when the bread is still warm and/or sticky;
- pulling the bread apart between two knives moving in a different direction;
- when the feed or push speed (pusher speed) of the bread is too fast, the bread is
compressed, in which the slices are permanently deformed or even broken.
[0006] Further, the tension of the known knives of 200 to 400 Newton leads to a large bending
moment in the stretcher, which leads to large dimensions and has disadvantages regarding
the dynamic behaviour of the bread slicer.
[0007] The aim of the present invention concerns to provide a bread slicer, which has a
number of advantages in relation to the above described bread slicers, in which the
knives play an important role and which knives are not suspended spring tensioned.
The aimed advantages concern a larger speed overlap of the knives, a lighter construction
by avoiding the needed heavy stretcher and therefore less vibrations and wear and
finally a much smaller exertion of force of the knives as total set exerted on the
loaf, by providing a step by step cutting of the bread and that it is minimally pushed
together lengthwise, by sharpening the knives in a suitable way and placing the sharpened
knives in a certain manner in the double oscillating supporting frame.
[0008] In short, the aim of the present invention is to provide a very efficient bread slicer,
which has a light construction, minimally crunches and/or damages the bread, needs
little driving power and in which the knives can easily be changed and the reversely
placed knives are still useable. Further, sharpening such knives should be as cheap
as possible.
[0009] In order to achieve the abovementioned aim, respectively advantages, a bread slicer
according to the invention is developed in a very inventive way, characterized in
that, the mentioned oscillated driven cutting instrument is constructed of two sets
of reciprocal driven rigidly restrained specially constructed knives, which in top
view on one side are mounted in a saw-tooth shape placeable in various layers constructed
in a wave- or V-shape alternating in a first or a second supporting frame, in which
the set-up of the knifes does not show a mutual overlap, in which the first and the
second supporting frames move the mentioned phase shifted sets of knifes oscillating
in their longitudinal axis.
[0010] The aim of minimum power, little vibrations and minimum damage to the bread or other
object is achieved.
[0011] By using knives which are sufficiently thick and broad, knives are created which
are sufficiently rigid to prevent tensioning and bending. This means, that the knives
are fixed and driven on one end. Through the other end of the knife only a guide is
applied. The chosen thickness of the knives lies between 0,6 and 3 mm. The width of
the knives lies preferably between 5 and 15 mm. By placing the single sided sharpened
knives according to a certain configuration in different layers (wave or V-shape),
the compression of the bread is herewith organized in such a way, that cutting the
bread leads to a lower compression. Each two cooperating knives exert a reciprocal
cutting movement.
[0012] Further, the device according to the invention is further developed, characterized
in that, the mentioned rigidly restrained knives are rigidly fixed in the mentioned
supporting frame on one end and on the other end oscillate in a slotted guiding construction,
in which both ends of the knives are constructed as reversible use useable, and in
which the mentioned knives are sharpened on one side.
[0013] The advantages are a fast changing of the knives and minimum deformation of the bread.
[0014] Furthermore, the device according to the invention is further developed, characterized
in that, the mentioned saw-tooth shaped set-up of the knives in a first or second
supporting frame, wherein the supporting frames are driven in such a way that they
mutually are moving in a reciprocal oscillating way with an eccentric gear, in which
the set-up knives are sharpened per pair in one layer facing each other.
[0015] The advantages are, that the pairs of knives always move reciprocal oscillating in
relation to each other and that sharpening the knives on one side is much cheaper.
[0016] The preferred construction of the invention will be described by way of example,
and with reference to the accompanying drawing.
[0017] In which:
- Fig. 1
- shows a schematic view in oblique projection of the set-up of the bread slicer according
to a preferred embodiment of the invention;
- Fig. 2
- shows a side view of the bread slicer according to a preferred embodiment of the bread
slicer applied in figure 1;
- Fig. 3
- shows a view in oblique projection of the preferred embodiment of the cutting mechanism
and pusher of the bread slicer;
- Fig. 4
- shows a bottom view in oblique projection of the cutting mechanism of the bread slicer
according to figure 3;
- Fig. 5
- shows a bottom view in oblique projection of the supporting frame with the knives
according to the invention, in which the reciprocal movement of the supporting frame
is clearly visible.
- Fig. 6A up to 6C
- show top views of the end of the knife for the usable fast fixing in the mentioned
supporting frame of figure 5; and
- Fig. 7
- here, the reciprocal movement of the knives is shown schematically.
Figure 1 schematically shows the set-up 1 of a bread slicer with the cutting mechanism
2 and pusher 3. Further a guard 4 is applied over the cutting mechanism.
Figure 2 shows in side view the cutting mechanism 2 at an angle α of approximately
60 degrees. Here, the knives 5', 5 are shown and how they are fixed in the supporting
frames 6 and 7, which can be driven with an eccentric gear 8. Here, the reciprocal
movement of the knives 5', 5 is clearly seen. The knives are herewith placed in a
V-shape in 5 rows (see figures 7 and 8).
Figure 3 shows a view in oblique projection of the preferred embodiment of the cutting
mechanism 2. In this figure it is clearly shown that the knives 5', 5 are fixed at
the bottom side in the supporting frames 6 and 7 by means of two pins, bolts or clamps
9, 10. The pusher 3 can be moved over the supporting plate 12 with the bread on it
(all at 60 degrees) towards the knives 5', 5. The moving mechanism (not indicated)
with guiding slots 14, 15 of the pusher 3 is clearly shown in figure 4. The movement
is done by means of an electromotor, which drives the guide block 16 along the axis
17, 18. The supporting frame 6 for the knives 5', 5 moves with a bush construction
19 along the axis 20. This is done in the same way at the supporting frame 7. The
eccentric mechanism 8 with the eccentric rod 21 are clearly visible.
[0018] In figure 5 the supporting frames 6 and 7 are enlarged. The supporting frame 7 has
a bush construction 22 and axis 23.
[0019] Figure 6A shows in top view the end 24 with a knife 5 with a first preferred embodiment
or concept of the attachment recesses 25, 26 for the means 9, 10 of the previous figures
3, 4, 5.
[0020] Figures 6B and 6C show a second embodiment or concept of the ends of the knives 5'
with the same cutting profile as knives 5, but with another attachment recess 27 for
fixing into the supporting frames 6 and 7, which is done with a bent away laminated
suspension spring 28 and which bent away laminated suspension spring 28 can be unlocked
with a special unlocking pin 29. During use, the bent away laminated suspension spring
28 locks the knives 5'. Thus, the knives 5' can be placed in a very simple way and
can be removed with an unlocking pin 29 to be placed. The extreme position of the
unlocking pin 29 is against knife 5' and with that it is avoided, that the laminated
suspension spring 28 is pulled further than its elastic permissible stress.
[0021] Figure 7 schematically shows the set-up of the knives in layers and the single sided
sharpened direction of the knives, in which the reciprocal movement of the knives
5', 5 is indicated per pair, in which, for example, the knives 5', 5 with a + are
moved upwards and the knives with a - are moved downwards at the same time.
[0022] Further, it must be noted that the mutual distance of the knives 5" can be reduced
in such a way, that these lay against each other or can be joined together to a single
knife 5", which gives a double sharpened knife. The movement direction of the bread
is indicated with arrow A.
[0023] Finally it has to be emphasized, that the above description constitutes preferred
embodiments of the invention, but that further variations and modifications are still
possible without departing the scope of this patent document.
1. Device for cutting loafs or breads and other mainly spacial products into slices,
mostly in order to offer the sliced bread packed to the client, in which in the mentioned
device specially constructed blades are mounted, in which supporting and guiding plates
or means for slicing loafs or breads have been applied, in which the mentioned bread
is moved with a pusher towards a number of oscillating or moving cutting instruments
with an approximate equal mutual distance and placed transverse on the bread, in which
the mentioned distances between the cutting instruments is done in such a way to allow
compression compensation, in which the movement or the oscillating movement in the
longitudinal axis of the mentioned cutting instrument is done by means of a special
driving mechanism, in which the whole is mostly provided with a housing to protect
the user, in which an intake and outlet opening is included, characterized in that, the mentioned oscillated driven cutting instrument is constructed of two sets of
reciprocal driven rigidly restrained specially constructed knives (5', 5), which in
top view on one side are mounted in a saw-tooth shape placeable in various layers
constructed in a wave- or V-shape alternating in a first or a second supporting frame
(6, 7), in which the set-up of the knifes does not show a mutual overlap, in which
the first and the second supporting frames (6, 7) move the mentioned phase shifted
sets of knifes (5', 5) oscillating in their longitudinal axis.
2. Device as claimed in claim 1, characterized in that, the mentioned rigidly restrained knives (5', 5) are rigidly fixed in the mentioned
supporting frame (6, 7) on one end and on the other end oscillate in a slotted guiding
construction (11), in which both ends of the knives are constructed as reversible
use useable.
3. Device as claimed in claims 1 - 2, characterized in that, the mentioned knives (5', 5) are sharpened on one side.
4. Device as claimed in claims 1 - 3, characterized in that, the mentioned saw-tooth shaped set-up of the knives (5', 5) in a first or second
supporting frame (6, 7), wherein the supporting frames are driven in such a way that
they mutually are moving in a reciprocal oscillating way.
5. Device as claimed in claims 1 - 4, characterized in that, the set-up knives (5', 5) are sharpened per pair in one layer facing each other.
6. Device as claimed in claims 4 and 5, characterized in that, each pair of knives making a cut at that moment are sharpened facing each other
and each time the separate knife is mounted in the first or the second supporting
frame (6, 7) and thus execute a reciprocal oscillating movement in relation to each
other.
7. Device as claimed in claim 6, characterized in that, the mentioned knives (5', 5) have a knurl, saw-tooth, smooth or another saw shape.
8. Device as claimed in claim 7, characterized in that, in cross-section the mentioned knives (5', 5) have a blade thickness between 0,6
and 3 mm, a width between 5 and 15 mm and a knife length of approximately 300 mm.
9. Device as claimed in claim 8, characterized in that, the material of the knives is blade steel or teflonized steel.
10. Device as claimed in claim 6, characterized in that, the driving of the first and the second supporting frame (6, 7) is constructed by
means of a balanced disc with an eccentric rod (21) connected with an eccentric mechanism
(8)
Amended claims in accordance with Rule 86(2) EPC.
1. Device for cutting loafs or breads and other mainly spacial products into slices,
mostly in order to offer the sliced bread packed to the client, in which in the mentioned
device specially constructed blades are mounted, in which supporting and guiding plates
or means for slicing loafs or breads have been applied, in which the mentioned bread
is moved with a pusher towards a number of oscillating or moving cutting instruments
with an approximate equal mutual distance and placed transverse on the bread, in which
the mentioned distances between the cutting instruments is done in such a way to allow
compression compensation, in which the movement or the oscillating movement in the
longitudinal axis of the mentioned cutting instrument is done by means of a special
driving mechanism, in which the whole is mostly provided with a housing to protect
the user, in which an intake and outlet opening is included, characterized in that, the mentioned oscillated driven cutting instruments are two sets of reciprocal driven
rigidly executed specially constructed knives (5', 5), which knives are completely
fixed at one end in an oscillately driven supporting frame in plate form, which set
of knives are mounted in top view on one side in a saw-tooth shape placeable in more
than two layers constructed in a wave- or V-shape alternating in a first or a second
supporting frame (6, 7), in which the set-up of the knifes does not show a mutual
overlap, in which the first and the second supporting frames (6, 7) move the mentioned
phase shifted sets of knifes (5', 5) oscillating in their longitudinal axis.
2. Device as claimed in claim 1, characterized in that, the mentioned rigidly executed knives (5', 5) are rigidly fixed in the mentioned
supporting frame (6, 7) on one end and on the other end oscillate in a slotted guiding
construction (11), in which both ends of the knives are constructed as reversible
use useable.
3. Device as claimed in claims 1 - 2, characterized in that, the mentioned knives (5', 5) are sharpened on one side.
4. Device as claimed in claims 1 - 3, characterized in that, the mentioned saw-tooth shaped set-up of the knives (5', 5) in a first or second
supporting frame (6, 7), wherein the supporting frames are driven in such a way that
they mutually are moving in a reciprocal oscillating way.
5. Device as claimed in claims 1 - 4, characterized in that, the set-up knives (5', 5) are sharpened per pair in one layer facing each other.
6. Device as claimed in claims 4 and 5, characterized in that, each pair of knives making a cut at that moment are sharpened facing each other
and each time the separate knife is mounted in the first or the second supporting
frame (6, 7) and thus execute a reciprocal oscillating movement in relation to each
other.
7. Device as claimed in claim 6, characterized in that, the mentioned knives (5', 5) have a knurl, saw-tooth, smooth or another saw shape.
8. Device as claimed in claim 7, characterized in that, in cross-section the mentioned knives (5', 5) have a blade thickness between 0,6
and 3 mm, a width between 5 and 15 mm and a knife length of approximately 300 mm.
9. Device as claimed in claim 8, characterized in that, the material of the knives is blade steel or teflonized steel.
10. Device as claimed in claim 6, characterized in that, the driving of the first and the second supporting frame (6, 7) is constructed by
means of a balanced disc with an eccentric rod (21) connected with an eccentric mechanism
(8)