Raw food cutter

Raw food cutter for cutting raw food into strips, with a base plate on whose top surface are provided two butting faces located in one plane and between which is arranged at least one knife row running substantially at right angles to the cutting direction and whose knives with approximately inverted U-shaped cutting edges that project above the butting faces and are open towards the underside of the base plate. The underside of the knife is at least partly inclined towards the base plate, the knife row is constructed in arcuate meander-like manner and preferably in one piece from a thin metal band. The thin metal band includes upper and lower transverse webs and lateral webs linking them and is fixed with the lower transverse webs in the base plate. The lower transverse webs are located below or level with the butting faces, while the upper transverse webs project above the butting faces and, based on the cutting direction, are oriented substantially parallel to the plane of the butting faces and the upper transverse webs are oriented parallel to the plane of the butting faces for forming double-edged knives. Based on the cutting direction, the upper transverse webs are centrally dented or depressed towards the base plate. The cutter is characterized in that on the base plate level with the knife rows are formed openings bounded by longitudinal webs and which are located below the upper transverse webs of knives, the lower transverse webs of knives and are jointly injection moulded into longitudinal webs of base plate.

BACKGROUND OF THE INVENTION 
The invention relates to a raw or uncooked food cutter. 
German patent 22 60 358 discloses a raw food cutter in the form of a 
kitchen grater, which is made from a plastic injection moulding and has a 
frame with rectangular holes into which pass in the cutting direction 
teeth curved arcuately downwards from the cutting edge. Further teeth are 
provided on the back of the kitchen grater. Such a grater can be used for 
shredding vegetables, fruit, etc. whilst expending relatively little 
energy. The shredded product is largely separated in the form of thin 
strips or grated and mashed. 
Admittedly the expenditure of energy is much less when using the 
aforementioned kitchen grater than with the other hitherto known graters, 
but is still too high in order to shred the product in a drawing movement, 
i.e. if the cutting edges of the knives are directed downwards. 
DE-OS 35 00 495 discloses a kitchen appliance for cutting potatoes, 
particularly semi-cooked potatoes, in which there are double-edged plastic 
knives connected in one piece with the base plate in the form of two 
successively displaced transverse rows. In this kitchen appliance, the 
cutting edges of the knives are initially parallel to the cutting 
direction and are then bent concavely downwards. This kitchen appliance is 
particularly suitable for producing curl-like potato strips, if the 
potatoes are semi-cooked beforehand. This kitchen appliance is less 
satisfactory and requires more energy expenditure when used for dealing 
with raw food. 
EP-OS 0 189 743 discloses a raw food cutter of the aforementioned type, 
which has in principle proved completely satisfactory. The problem of the 
present invention is to improve the manufacture and handling of said 
cutter in such a way that the cutting resistance is further reduced and 
manufacture is simplified and made less expensive. 
SUMMARY OF THE INVENTION 
According to the invention this problem is solved by the features of the 
invention as described herein. 
A U-shaped cross-section is retained over a considerable length of the 
cutting process. As a result the cutting forces are significantly reduced 
compared with conventional kitchen graters. Instead of being displaced, 
the material cut is cleanly cut through. Surprisingly there is also no 
clogging of the base plate free space left under the knives. The 
substantially parallel arrangement of the knife cutting edges in fact 
appears to improve the free cutting of the individual knives. Apart from 
simple manufacture by stamping and the prior, two-sided, mechanical 
sharpening, the advantage of constructing the knife row from a metal band 
is that the latter can be relatively thin and is e.g. approximately 1/10 
mm. This thin cross-section of the cutting edges naturally extends over 
the entire cutting edge length and depth, so that during cutting the 
product is not squeezed. The significance of this advantage is immediately 
apparent if it is remembered that the thickness of the lateral webs must 
be pressed through the cut material. Despite the use of such a thin metal 
band, the enormous stability of the knife is surprising. This is on the 
one hand apparently due to the meander-like or undulating construction of 
the metal band and on the other to the fact that each lower transverse web 
is fixed in the base plate. 
Admittedly German utility model 19 91 402 discloses a domestic cutting 
appliance for cutting chips or French fries, in which there is 
rectangularly wave-like bent knife arranged at right angles to the cutting 
direction. This knife is fixed to the facing longitudinal strips of the 
kitchen appliance. However, as a result of the knife size and cutting edge 
thickness, it is not suitable for cutting raw food. 
A so-called waffle cutter is also known, in which a wave-like bent knife 
fitted in sloping manner with respect to the cutting direction is fixed in 
the rear bearing plate. However, this cutter also has excessively large 
knives and cutting edge thicknesses. 
As stated hereinbefore, when cutting raw food it is a question of producing 
very thin strips. If these strips are to be cut by means of U-shaped 
knives, the problem arises that the lateral webs must pass through the 
vegetable. With the large number of lateral webs necessary for such raw 
food graters, the cutting edge thickness can be summated or added to such 
an extent that not only is the cutting resistance increased, but also 
there is a considerable increase in the risk of the already cut strips 
jamming. 
However, problems can occur due to the resulting stability problems of the 
knife row through merely reducing the thickness of the cutting edge. These 
contradictory requirements have been taken into account for the first time 
by the present invention. 
According to a preferred embodiment, the upper transverse webs for forming 
double-edged knives are oriented parallel to the plane of the butting 
faces and, based on the cutting direction, are in each case centrally 
dented or depressed towards the base plate. Thus, the cutting process 
takes place with substantially no additional resistance. The deflection of 
the cut product by the depressions only takes place when it has acquired a 
certain length, so that to a greater or lesser extent it bends round of 
its own accord. Due to these features it is easy for the housewife to cut 
the product by a reciprocating movement during each stroke or travel. This 
is not so obvious, because hitherto the high cutting resistance in the 
case of raw food graters has led to a relatively poor cutting result 
during the return movement, i.e. less is cut during the return movement 
than during the outward movement. 
An advantageous deflection of the cut strips is obtained in that the 
depressions of the upper transverse webs are roughly triangular, when 
considered at right angles to the cutting direction. 
Advantageously the depressions end at a distance above the plane of the 
butting faces, which is sufficient for the free cutting of the knives. In 
addition, the deflecting forces are kept very small by the depressions. 
An advantageous distance between the center of a depression and the 
associated cutting edge of a knife corresponds to roughly two to three 
times the depth of the depression. The distance from the edge of a 
depression up to the associated, adjacent cutting edge roughly corresponds 
to the depth of a depression. As a result of these size ratios the cutting 
process is particularly advantageous, whilst the distance from the edge of 
a depression to the adjacent cutting edge can also be made somewhat 
larger. 
According to a preferred embodiment, the width of an upper transverse web 
roughly corresponds to that of a lower transverse web. 
Preferably according to a further development of the raw food grater, there 
are two knife rows in succession in the cutting direction and displaced at 
right angles thereto on the base plate. 
Although it is preferred to arrange the knife rows in sloping manner with 
respect to the cutting direction, the longitudinal extension of the knife 
extending in the latter direction, according to an embodiment the knife 
rows are fitted to the base plate at right angles to the cutting 
direction. Advantageously the base plate is made from plastic. 
A particularly stable fitting of the knife row to the base plate is 
obtained if openings bounded by longitudinal webs provided level with the 
knife rows on the base plate located below the upper transverse webs of 
the knife, the lower transverse webs of the knife also being injection 
moulded in the longitudinal webs of the base plate. 
The free cutting of the knives is further facilitated in that the openings 
are made longer than the upper transverse webs of the knives and terminate 
at a distance from the cutting edges of the latter. 
A good anchoring of the lower transverse webs in the longitudinal webs of 
the base plate is brought about in that impressions are made on the lower 
transverse webs for anchoring the latter in the plastic. 
The good anchoring can be further improved in that the depressions are 
provided with openings for the passage of the plastic. During the 
injection moulding of the raw food cutter, the plastic passes through 
these openings, which leads to a positive connection between the lower 
transverse webs of the knife and the base plate. 
The anchoring of the lower transverse webs is also improved in that, based 
on the cutting direction, the impressions are located in the center of the 
lower transverse webs.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
FIG. 1 shows a raw food cutter 1 for cutting raw food strips. Cutter 1 
comprises a base plate 2, on whose top surface 3 are provided two butting 
faces 4 and 5 located in one plane. Between butting faces 4, 5 are 
provided two knife rows 6, 7 displaced reciprocally or displaced in 
relation to each other and at right angles to cutting direction A. Knife 
rows 6, 7 have knives with U-shaped cutting edges 8, whose height projects 
over the butting faces 4, 5 and are open towards the underside 9 of base 
plate 2. The knife underside is at least partly inclined towards the base 
plate (cf. FIG. 2). 
As can be gathered from FIG. 1, the knife rows in each case comprise a thin 
metal band 10 with a thickness of approximately 1/10 mm. Metal band 10 is 
bent in meander-like manner, accompanied by the formation of upper 
transverse webs 11, lower transverse webs 12 and lateral webs 13 
interconnecting the same. 
As can be clearly gathered from FIG. 3, the lower transverse webs are fixed 
in the base plate and positioned below the butting faces 4, 5. The upper 
transverse webs 11 project over and beyond butting faces 4, 5 and, based 
on the cutting direction A, are oriented substantially parallel to the 
plane of butting faces 4, 5. 
As can be gathered from the drawings, knife rows 6, 7 are constructed in 
double-edged form, the upper transverse webs 11 being centrally provided 
with dents or depressions 14 directed towards the base plate. 
It can be gathered from FIGS. 2 and 3 that the depressions 14 of the upper 
transverse webs 11 are roughly triangular, considered at right angles to 
cutting direction A. Depressions 14 terminate at a distance above the 
plane of butting faces 4 and 5. 
As can be clearly gathered from FIG. 2, the distance between the centre of 
a depression 14 and the associated cutting edge 8 of a knife is roughly 
two to three times the depth of depression 14. Measured from the top edge 
of a depression 14, the distance to the associated adjacent cutting edge 8 
roughly corresponds to the depth of a depression. 
As can be gathered from FIG. 1 the width of an upper transverse web 11 
roughly corresponds to that of a lower transverse web 12. 
Although the knife rows 6, 7 could also be inclined to the cutting 
direction A, in this embodiment they are fitted to the base plate 2 at 
right angles to cutting direction A. 
Base plate 2 is made from plastic. The metal bands 10 from which the knife 
rows 6, 7 are made are also injection moulded into the base plate 2 of the 
raw food cutter 1. For this purpose on base plate 2 and level with the 
knife rows 6, 7 are provided openings 16 bounded by longitudinal webs 15 
and which are located below the upper transverse webs 11 of knives 6, 7. 
The lower transverse webs 12 of knives 6, 7 are jointly injection moulded 
in to the longitudinal webs 15 of base plate 2. 
Impressions 17 are made in the transverse webs for the better anchoring of 
the lower transverse webs 12 in the longitudinal webs 15 of base plate 2. 
The ensure even better anchoring of the transverse webs of the knives in 
the longitudinal webs of the base plate, the impressions 17 are provided 
with openings 18 through which the plastic can pass during injection 
moulding. Based on cutting direction A, impressions 17 and also openings 
18 are located in the center of the lower transverse webs 12. 
As can be particularly well gathered from FIG. 2, openings 16 are longer 
than the upper transverse webs 11 of knives 6, 7 and terminate at a 
distance from the knife cutting edges 8. This cannot be gathered as 
clearly from FIG. 1. 
The invention functions as follows. The raw food cutter enables vegetables 
to be cut into very fine strips without any pulping or other damage 
occurring. 
At the start of the shredding process, the material for cutting is placed 
on the upper butting face 4 and is then guided against the first knife row 
6. When the product strikes against the cutting edge 8 of the first knife 
row 6, the upper transverse webs 11 and the associated lateral webs 13 of 
knife row 6 pass into the product without bending down the already cut 
part. 
Only when the leading edge of the cut material reaches depression 14 is the 
cut strip deflected downwards with a relatively long lever arm of 
approximately two to three times the depth of depression 14. This 
deflection is sufficient for the cut strips to pass through openings 16 in 
such a way that they pass out of the openings 16 on the underside of base 
plate 2. 
After passing through the first knife row 6, the cut material encounters 
the second knife row 7, which is displaced with respect to the first knife 
row 6. The cut product parts left behind are now cut in the form of strips 
as described hereinbefore. 
When the cut product is located on the lower butting face 5, it is once 
again brought against knife row 7 by a pulling movement of the arm, but 
this now takes place in the opposite direction. 
As a result of the extremely small cutting resistance, the entire surface 
of the cut product remains on the butting face 5, without any tilting 
occurring. This is not so obvious, because as a result of the unfavourable 
force application to the cut product during the upward pulling movement, 
even in the case of a moderate resistance on its leading edge, said 
product would tend to lift from the butting face 5, but this problem does 
not occur here. 
As the strips cut during the outward movement have already dropped out of 
the openings 16, the latter are now free for the passage of the strips cut 
during the return movement. 
After passing knife row 7, in the same way as described hereinbefore 
further strips are cut from the cut product on knife row 6. 
The inventive features disclosed in the above description, the drawings and 
claims can be essential to the realization of the different embodiments of 
the invention, either singly or in random combination.