Fruit and vegetable peeler

Peeler for a product (P), such as a fruit or vegetable, using a rotating tool moved in relation to the product so as to explore the surface of the latter and mark on it successive parallel turns, characterized in that the said tool is in the form of a vertical cutter (T) and comprises a part of revolution (1) of small diameter and a small number of teeth, whether cutting teeth or not, forming projections (2), this tool (T) being driven in rotation about its axis (AT) at a high speed and in such a direction (S) that the said projections (2) engage the skin of the product from below, starting from the adjacent turn already peeled.

The invention relates to appliances intended for skinning or peeling 
various products, such as fruit or vegetables, that is to say removing 
their skin, casing or husk which hereinafter will be referred to as skin. 
For the peeling of fruit, it is known to use the principle of the lathe, 
with one or more fixed or rotary tools which have at least one cutting 
part and which attempt to imitate manual peeling, that is to say detach a 
continuous peel, such as, for example, in the devices described in the 
documents FR-A-No. 1,585,006, U.S. Pat. No. 3,680,614 and FR-A-No 
1,481,314. On an automatic appliance, the presence of such a continuous 
peel is a serious disadvantage because of its tendency to clog and impede 
the action of the tool. To remedy this, it is known from the document U.S. 
Pat. No. 3,113,603 to use a rotary knife with a cylindrical cutting edge, 
combined with a disc which supports the cylindrical cutting edge and which 
is provided with apertures sharpened in the plane of the disc, so as to 
cut the ribbon of peel transversely into smaller portions making it easier 
to discharge it. It is also known from the document FR-A-No. 1,248,668 to 
use a rotary knife in the form of a very flat milling cutter, having a 
large number of cutting teeth distributed over a considerable diameter, in 
order to produce small chips, the discharge of which is left to chance. 
The devices described above are not suitable for the peeling of vegetables, 
on the one hand because of the rapid wear of the cutting edges, especially 
where products with a soily skin are concerned, and on the other hand 
because of the irregular shapes of vegetables, such as potatoes, and the 
differences in hardness of their flesh, such as the difference between a 
carrot and a potato. Consequently, grinders or abrasive devices processing 
the vegetables in bulk under a stream of water are preferably used, 
although these entail very substantial weight losses during peeling, or 
even, in very special cases, such as potatoes, shaving knives are used, 
but these are very fragile and again have the disadvantage of being 
clogged by the peel. 
The object of the invention is to eliminate the preceding disadvantages by 
providing a device which, without special adaptation, is suitable for all 
the commonest types of fruit and vegetables, which eliminates the problem 
of clogging and discharge of the peelings and which also overcomes the 
problem of wear of the cutting edges and the difficulties attributable to 
irregular shapes. 
The invention is based essentially on the use of a tool of the 
vertical-cutter type comprising: 
a part of revolution of small diameter, capable of penetrating even into 
the concave portions of the irregular shapes, 
a small number of teeth, either cutting teeth or not, which project beyond 
this part of revolution, this number preferably being equal to two to 
obtain a balance, 
this vertical cutter being driven in rotation at a high speed, so that the 
tangential speed of the projections exceeds 8 m/s and is preferably in the 
region of 20 m/s, in order constantly to throw the detached particles of 
skin far away in proportion as the vertical cutter explores the surface of 
the product in parallel turns, and 
the direction of rotation of the vertical cutter being directed so that the 
projections engage the skin of the product from below, starting from the 
adjacent turn already peeled. 
The characteristics of this vertical cutter, in particular its high 
rotational speed, are also expedient in that they only exert very low 
uniform forces, in particular making it possible 
to require only a very low drive torque for the vertical cutter by means of 
a separate motor with a direct drive or with a transmission, 
to give this vertical cutter a sensitive mounting, so that its surface of 
revolution bears on the surface of the product, but with only a very 
slight force or restoring torque if the assembly has a tilting mounting, 
finally, to require only a low torque to drive the product in rotation and 
only a low traversing force for the device intended for generating the 
relative movement of systematic exploration in parallel turns. In 
particular, the product can be driven in rotation and in translation by 
means of a simple spindle in the form of a corkscrew, allowing direct 
screwing into and unscrewing from the product using only a fraction of the 
travel of the same translational and rotational movements. 
According to an important feature of the invention, the axle of the 
vertical cutter is mounted in bearings, so as to oscillate about a 
perpendicular pivot pin, this pivot pin itself being mounted in the 
bearings of a fork-shaped holder capable of rotating about an axle which 
is perpendicular to or even at right angles to and offset relative to the 
pivot pin, so that 
at the start of operation, the pivot pin forms an angle of approximately 
45.degree. with the spindle carrying the product, in such a direction 
that, when the vertical cutter meets the product, the vertical cutter 
automatically moves away obliquely, and 
at the end of operation, this pivot pin forms an angle of opposite 
direction and preferably approximately 20.degree., with this same spindle. 
This arrangement is intended to ensure an automatic mode of operation and a 
substantially constant apparent pitch between the turns.

FIGS. 2 and 6 in particular illustrate the vertical cutter T according to 
the invention, which has a surface of revolution 1, in this case 
cylindrical, which is capable of bearing on the surface of the product P 
to be peeled, so as to limit penetration, this surface having a very small 
diameter, for example of the order of 20 mm. Moreover, the vertical cutter 
has a very small number of projections 2, for example two to ensure a 
balance during rotation. The vertical cutter T, together with its bearing 
surface 1, can be made, for example, of moulded plastic, whilst the 
projections 2 are advantageously formed by the projecting part of a metal 
blade which can be sharpened or not. The amount by which each projection 
extends beyond the surface 1 defines the maximum depth of cut and, if 
appropriate, can be modified by means of several types of vertical cutter. 
According to an essential characteristic of the invention, this vertical 
cutter rotates about its axis AT at a very high rotational speed, for 
example 20,000 revolutions per minute, so that the tangential speed of the 
projection 2 is at least of the order of 20 m/s or, at all events, higher 
than 8 m/s. On the other hand, this high rotational speed only requires a 
relatively low torque, so that it can easily be provided by means of a 
small direct-drive motor 3 located at the other end of the shaft A of axis 
AT. However, any other type of transmission, for example by means of a 
belt, or any other type of drive, for example by means of a turbine, could 
be used. 
According to the invention, the assembly 4 comprising the bearings 5 and 6 
of the shaft A and, if appropriate, the motor 3, as in the present case, 
or the receiver of the transmission, is mounted so as to oscillate about a 
pivot pin AM perpendicular to AT. This pivot pin AM is carried, for 
example, by a fork-shaped holder C which can be seen particularly in FIG. 
3, 5 and 6 and which is itself mounted so as to be rotatable about an axle 
AC perpendicular to the motor pivot pin AM and preferably offset, that is 
to say not concurrent with the preceding one, as can be seen especially in 
FIG. 6. At the same time, a restoring torque exerted, for example, by a 
spring r produces a rotation of the assembly 4 about this axle, in order 
to generate, in the region of the vertical cutter T, a low force pressing 
the latter against the product P of the order of 0.3 N or at most 0.5 N. 
In fact, the high rotational speed of the vertical cutter does not make it 
necessary to exert a high pressure on the product. 
The product P itself, whether a vegetable or fruit, can be driven in a 
helical movement, to ensure that the vertical cutter T systematically 
explores its surface, without the need for either a high rotational drive 
torque or a high translational drive force. In the example illustrated, 
this double driving of the product P is ensured by means of a short 
spindle B, the end of which is pointed and cut in the form of a 
large-pitch screw in the manner of a corkscrew, so that it can be screwed 
directly into a short length of the product corresponding to the shortest 
length dimension of the products being processed. In this way, the simple 
rotation of the spindle B on itself is sufficient to ensure that the 
spindle penetrates into the product P, for example momentarily immobilized 
by hand, and then, in a second stage, the rotational and translational 
drive of this product. 
In the example illustrated, there is for this purpose a vertical screw V 
which can be seen in FIGS. 1 to 4, which is driven in slow rotation from a 
second motor 7 in the example shown, by means of a suitable reducing gear 
8 located under the base 9 of the appliance and driving the lower end of 
the screw V, preferably by means of friction. 
Mounted on this screw V is a carriage 10 which can be seen particularly in 
FIGS. 2 and 4 and which forms a nut capable of moving in translation along 
the screw in one direction or the other as a result of the rotation of the 
latter. This carriage 10 takes the form of an arm, the end of which 
carries the bearings 11 and 12 of the base of the preceding spindle B. A 
suitable transmission makes it possible to transmit the rotational 
movement of the screw V to the spindle B. In the example illustrated, this 
transmission takes place by means of a pulley 13, keyed on the spindle B 
between the bearings 11 and 12, and a belt 14 passing directly between two 
threads of the screw V, thus ensuring both the frictional drive of the 
belt and its longitudinal travel under the same conditions as the carriage 
10. However, any other type of transmission could be used. The 
transmission ratio can be equal to one or different from one. 
Because of the unavoidable friction between the screw V and the carriage 10 
and between the spindle B and its bearings 11 and 12, the torque of which 
is transferred to the screw by the belt 14, and also because of the 
inertia and drive resistance of the product P which opposes the movement, 
when the screw V is driven in rotation the carriage 10 naturally tends to 
rotate together with this screw rather than move in translation on the 
latter. To ensure this translation, the carriage 10 is therefore equipped 
with a rear extension 15 capable of coming up against and sliding 
vertically on a stop 16 integral with the appliance frame, when the screw 
rotates in an anti-clockwise direction as seen from above, and likewise to 
come up against and slide vertically on another stop 17 integral with the 
frame, when the screw rotates in a clockwise direction. Furthermore, in 
the latter case, there is also an intermediate stop 18 which, as can be 
seen in FIG. 2, only extends over a small portion of the height. 
In particular, when the extension 15 of the carriage is up against the stop 
17, with the screw rotating in a clockwise direction, the spindle B is in 
the position B.sub.1 on the left in FIG. 4, underneath the vertical cutter 
T and substantially in line with the latter. The slow rotation of the 
screw V in the direction indicated therefore causes the upward helical 
advance of the product P at a pitch corresponding exactly to that of the 
screw V, if appropriate divided by the transmission ratio indicated above. 
At the same time, according to the invention, the holder C is positioned at 
the outset, in such a way that the motor pivot pin AM is inclined 
substantially at 45.degree. C. relative to the axis AB of the spindle B 
and in such a direction that, when the vertical cutter T meets the top of 
the product P, the vertical cutter consequently moves away obliquely in 
the direction F which distances it from the axis AB, as shown in FIG. 5. 
Subsequently, according to the invention, the pivot pin AM is forced to 
rotate slowly about the holder axle AC, until it goes beyond the vertical 
and reaches a similar inclination in the opposite direction. However, this 
second inclination can stop at approximately 20 degrees relative to the 
vertical. 
During this movement, the vertical cutter explores the entire surface of 
the product P, at the same time marking parallel grooves, the apparent 
pitch of which is substantially equal to that indicated above, the 
direction of rotation of the vertical cutter T, as represented by the 
arrow S in FIGS. 1 and 5, being selected so that the vertical cutter 
always engages the skin of the product P from below, starting from the 
preceding turn already peeled. This is especially important where soily 
products, such as potatoes or carrots, are concerned, to prevent undue 
wear of the projections 2 and to leave the peeled product P perfectly 
clean. 
This rotational movement of the holder C about the axle AC can be generated 
by any suitable means, whether continuous or intermittent, but in the 
example illustrated, it can be obtained in a very simple way by means of a 
pulley 19 which drives the holder C by means of friction and which is 
itself driven by a belt 20 from the screw V and by means of a dual 
assembly consisting of a wheel 21 and a tangent screw 22, the latter being 
carried at the end of the screw V. The shaft 23 driven by the wheel 21 
drives the belt 20 at its other end. 
When the vertical cutter T engages the upper crown of the product P, it is 
expedient to operate at the very centre in the axis AB, whereas, when the 
vertical cutter finishes peeling the product P in the vicinity of the 
spindle B, it is expedient to shift the position of this vertical cutter 
relative to the axis AB of this spindle an amount just sufficient to 
prevent the vertical cutter from encountering the spindle B or the 
carriage 10. According to the invention, this can be achieved very simply 
by making the assembly consisting of the holder C and the pulley 19 slide 
along its axle AC by providing, for this purpose, an evolute cam 24 
retained between a boss 25 and a finger 26 which are integral with the 
holder, in order to ensure, as a result of this double guidance, the 
progressive retraction of the assembly and its return to the initial 
position in the movement in the opposite direction. 
Moreover, since the length of the products P can vary greatly, the moment 
at which the rotation of the holder C about its axle AC is to start must 
be delayed until the vertical cutter T actually comes into contact with 
the product P. To achieve this, there is a substantially cylindrical guide 
27 which can be seen particularly in FIGS. 1, 3, 5 and 6 and on the edge 
of which bears a stop finger 28 limiting the tilting travel of the 
assembly 4 about the pivot pin AM. In the initial position, this finger 28 
penetrates to the bottom of a slot 30 of the guide 27 and comes up against 
a retractable stop 31 which opposes the rotation of the holder C up to the 
moment when, the vertical cutter T having encountered the product and 
having been lifted by the latter in the direction F, the finger 28 escapes 
from the stop 31 which defined the initial position and begins its slow 
rotation as a function of the drive described. 
In view of the progressive retraction of the pulley 19, as explained above, 
the drive pulley integral with the shaft 23 can advantageously be replaced 
by a portion of a helical screw 32, as in the example illustrated, but any 
other transmission means could of course be used. Obviously, the angular 
position of the holder C at the end of peeling is defined by a simple 
angular stop operating in the region of the cam 24 or the guide 27. 
The device is advantageously completed by a centering scoop 33 which can be 
seen in FIGS. 1 and 4 and which is articulated about an axle 34 integral 
with the frame of the appliance. This scoop has a concave part 35 used for 
centering the base of the product in line with the spindle B when the 
latter is in the mid-position defined when the rear extension 15 of the 
carriage 10 comes up against the intermediate stop 18. It can also be seen 
that the scoop 33 has a releasing slot 36 allowing the passage of the base 
of the spindle B when the carriage 10 rotates from the mid-position to the 
position B.sub.1 in FIG. 4. 
The general movement of the appliance can be followed in the Figures, 
particularly in FIG. 1. It is assumed, at the start, that the appliance is 
stopped in the position represented by unbroken lines, that is to say with 
the carriage 10 in the mid-position and at the lower end of the travel of 
the screw V. The user then places a product P in the centering cavity 35 
by hand and actuates a manual control which starts the motor 7. This 
manual control can consist simply of a contact (not shown) actuated as a 
result of the start of the downward movement of the scoop 33, during which 
the base of the product comes up against the tip of the spindle B. As a 
result of the rotation of the screw in a clockwise direction and because 
of the rear stop 18, the carriage 10 rises vertically, still in the 
mid-position, whilst the spindle B is driven in an anti-clockwise 
direction by the transmission 14 described, thus automatically causing it 
to rise and at the same time be screwed into the product. If the pitch of 
the corkscrew-part of the spindle B is substantially equal to the pitch of 
the screw V, taking into account the possible transmission ratio between 
the two axles, the spindle rises without any axial displacement of the 
product which is, of course, immobilized in terms of rotation by the 
operator's hand. 
At the end of a specific travel of the carriage 10, detected by a suitable 
limit switch (not shown), the spindle B has been screwed over its entire 
length exactly, and at the same time the rear extension 15 of the carriage 
10 has arrived at the upper end of the stop 18, but without escaping from 
the latter. The motor 7 is then stopped by means of this limit switch. 
After withdrawing his hand, the operator then actuates another manual 
control which can consist, for example, of an additional travel of the 
scoop 33, and another contact restarts the motor 7, still in the same 
direction, for example by short-circuiting the preceding limit switch. As 
soon as the carriage starts to rise, its rear extension 15 then escapes 
from the intermediate stop 18, so that the assembly consisting of the 
carriage 10, spindle B and product P carried by the latter begins to 
rotate together with the screw, until the stop 17 comes into action, as 
explained above. 
Subsequently, still in the course of the same movement, the product P 
starts its helical upward movement. At the same time, the vertical cutter 
T rotates in the direction indicated, but the holder C driven frictionally 
by the pulley 19 nevertheless remains in the stationary position, locked 
by the finger 28 which bears on the stop 31. After a certain number of 
revolutions depending on the length of the product P, the top of the 
latter encounters the vertical cutter T, thus causing a peeling spiral to 
be made on its end crown, at the same time as the release of the finger 28 
allowing the subsequent slow rotation of the holder C about its axle AC, 
as explained above. 
The product continues to rise, and the vertical cutter explores its 
surface, marking on it turns which change from a virtually plane spiral to 
virtually helical turns, terminating once again at the other end in a 
substantially plane spiral, all these turns having a relatively constant 
apparent pitch because of the progressive variation in inclination of the 
pivot pin AM, as indicated above. At the clination of the pivot pin AM, as 
indicated above. At the same time, as has been seen, the progressive 
retraction of the holder C makes it possible for the vertical cutter T to 
avoid encountering the spindle B, the latter moreover having at its base 
an unthreaded part of a length substantially equal to the diameter of this 
vertical cutter, to prevent the latter from encountering the carriage. 
The vertical cutter returns to the vicinity of the axis AB according to the 
position of the carriage 10 corresponding to the top of its travel, this 
position being independent of the length of the product P and being 
determined by an upper limit switch (not shown). 
The actuation of this limit switch simply causes the reversal of the motor 
7, and, if appropriate, the motor 3 can either continue in the same 
direction or be stopped or run in reverse. This reversal of the direction 
of rotation of the screw V then causes the carriage to be driven from left 
to right in FIG. 1 up to the position represented by B.sub.2 in FIG. 4. In 
this position, as shown in FIG. 3, the unthreaded base of the spindle B 
engages into the slot 36 of a discharge station consisting of a horizontal 
or sloping surface 37 followed by a ramp 38 or a discharge chute. 
When the spindle B is in line with this new position, that is to say when 
the rear extension 15 of the carriage 10 encounters the first stop 16, the 
spindle B starts a helical downward movement in the unscrewing direction. 
Consequently, the product P is itself driven freely in this helical 
movement, until its base meets the bearing surface 37 of the discharge 
station. The effect of this is to immobilize it as a result of friction, 
thus making it possible to unscrew the spindle B which, once removed from 
the product P, continues its downward movement alone to the bottom end of 
its travel. 
Here, another lower limit switch (not shown) once again causes a reversal 
of the running direction of the motor 7, thereby driving the carriage 10 
as a whole into the mid-position B in FIG. 4, its rear extension 15 coming 
up against the intermediate stop 18. Another electrical contact (not 
shown), which detects the arrival of this rear extension 15 against the 
stop 18 in the low position, causes the motor 7 and, if appropriate, the 
motor 3 to stop, the appliance thus resuming the initial position for the 
start of a cycle. Of course, during this last movement, the upper tip of 
the spindle B just passes under the scoop 33 to take up position below the 
bottom of the slot 36. 
ln actual fact, the entire peeling cycle just described proceeds 
automatically and lasts scarcely 10 seconds, this time being used by the 
operator to take hold of another product and place it once again in the 
centering scoop. 
During the entire peeling cycle, the particles of skin of the product P, 
which are finely shredded by the projections 2 of the vertical cutter T, 
are thrown tangentially towards a zone of reduced extent, where there is 
no risk at all that their accumulation will impede the running of the 
appliance. Of course, this zone is preferably designed in the form of a 
removable receptacle (not shown) allowing it to be cleaned. Conventional 
protective devices, which are not shown for the sake of simplification, 
make it possible to protect the mechanism, particularly the screw, against 
dirt being thrown accidentally. 
In practice, the same type of vertical cutter can serve practically for 
most products, whether vegetables with hard flesh, such as carrots, or 
vegetables with soft flesh, such as potatoes, or even vegetables with 
tough flesh, such as turnips or onions, and also fruit with a thin skin, 
such as apples or pears. Because there is no need for any adaptation or 
any calibration of the products, it is therefore possible for the user to 
string together different products, for example carrots, potatoes, 
turnips, onions, etc. without having to change anything in the appliance. 
Where fruit with a thick skin is concerned, especially oranges and lemons, 
it is possible, as was seen above, to use a special vertical cutter, the 
projections 2 of which project to a greater extent. Another solution is to 
act on the relative speed of the vertical cutter in relation to the speed 
of the screw, this being particularly simple in the example described, in 
which there are two independent motors 3 and 7. Finally, a last solution 
involves restarting the peeling cycle several times on the same citrus 
fruit. This last solution also has the advantage that the zest of the 
fruit can be recovered, if desired, in the abovementioned receptacle 
during the first pass, whilst the pith is eliminated during the following 
pass or passes. 
Finally, it should be noted that, despite the absence of water in the 
appliance, all the peeled products, whether fruit or vegetables, leave the 
discharge station perfectly clean because of the peeling method used and 
scarcely need to be cleaned at all before being used.