Device for reducing peelable products such as potatoes in size to a predetermined shape

Abstract: A device for reducing peelable products such as potatoes in size to a predetermined shape, consisting of at least one pair of mutually adjacent rotatably driven reducing elements (1,2), the outer surface of which has at least one constriction (7) such that two oppositely situated constrictions (7) form a passage opening (9) between the elements for the reduced product, wherein the surface of at least one element (1,2) is provided with a reducing surface, wherein the constriction is formed such that, as seen in top view, the passage opening acquires a predetermined shape in order to obtain a product with an associated revolutional shape, for instance spherical, elliptical or any other composite form.

Description: The invention relates to a device for reducing peelable products such as potatoes in size to a predetermined shape, consisting of at least one pair of mutually parallel rotatably driven reducing elements, the outer surface of each of which has at least one constriction such that two oppositely situated constrictions form a passage opening between the elements for the reduced product. Such a device is known from DE-A-3426510. The known device is embodied with two grinding rollers arranged parallel adjacent to each other so that a row of mutually parallel adjacent circular passage openings are formed. The roller elements are provided with a grinding layer, such as carborundum. By discharging the products, for example potatoes, from the top onto the rotating rollers a quantity of material will be taken off the product for reducing in size by the surface of the elements, whereby this must be reduced to a sphere. This has been found in practice to be unsatisfactory because the products are ground into an oval-shape as a result of the peripheral velocity differences of the mutually adjacent cross sections of the reducing elements, whereby the product cannot spin round freely, which is a condition for the removal of material on all sides. A further drawback to a roller having such a grinding surface is that this can easily become congested with material taken off the product, whereby the grinding action deteriorates. The invention has for its object to obviate the above mentioned drawbacks and provides to this end a device which is characterised in that the constriction in the outer surface of each reducing element is defined by knife-like protrusions comprising cutting surfaces for cutting the products to the predetermined shape. Due to the knife-like protrusions a cutting action takes place on the surface of the product wherein each knife-like protrusion cuts a small piece from the surface of the product. It should be noted that a device having knife-like protrusions extending from a constriction in the outer surface of a single drum-like roller is known per se from DE-C-69821. This known device is, however, intended for peeling and grating rather than for shaping, and the knife-like protrusions do not therefore define the constriction. Preferred embodiments of the device in accordance with the present invention form the subject matter of the dependent claims. Above mentioned and other features of the invention will be elucidated further in the figure description hereinbelow of a number of embodiments. In the drawing: fig. 1 shows a perspective schematic view of the device according to the invention with partially broken away parts, fig. 2 shows a top view of a part of rollers according to an embodiment which does not form part of the invention, fig. 3 and 4 show respectively a top view and an axial standing section of a first embodiment of the roller elements according to the invention, fig. 5 and 6 each show a top view of a second and third embodiment of the roller elements according to the invention. The device shown in fig. 1 comprises two rollers 1, 2 arranged mutually parallel which are suspended rotatably at either end in bearings (not shown) in a randomly chosen frame (not shown). Arranged above the rollers is a supply bin 3 for receiving the products, for example potatoes, for reducing in size. According to the invention the rollers 1, 2 are driven, for which purpose the shafts 4 of the rollers 1, 2 are each provided with a toothed wheel 5 which are both driven by a common toothed wheel 6. The toothed wheel 6 is connected to a drive, for example an electric motor. The diameter of the toothed wheels 5 of the one roller 1 may differ relative to the other roller 2 in order to realize a disparate peripheral velocity of the rollers 1, 2. According to the invention the outer surface of the rollers 1, 2 is in any case provided with at least one constriction 7, see figs. 3-6, which constriction connects onto a disc-shaped member 8 which can be repeated along the length of the rollers 1, 2 in order to obtain a number of mutually adjacent constrictions 7. The rollers 1 and 2 are disposed relative to each other such that the constrictions 7 lie mutually opposite so that a continuous opening 9 is formed. The constrictions 7 are defined by knife-like protrusions 11, 12 or 13, respectively. The operation of the above described device is as follows. When products are arranged in the supply bin 3 and the rollers 1, 2 are caused to rotate, the products will, as a result of the cutting action of the knife-like protrusions defining the constriction 7, be reduced such that the product will also start to spin as a result of the rotating action, preferably with a disparate peripheral velocity of the rollers 1, 2, so that as a result the products take on a spherical shape, see P in fig. 1. As soon as the product has reached the correct dimensions, as designated by the broken line 10 in fig. 2, it will fall downward through the passage opening 9. The form 7 is self-centering. Fig. 3 and 4 show a first embodiment wherein the constriction 7 in the outer surface of the rollers 1, 2 is obtained by arranging circular curved knife strips 11 which extend in radial sense, see fig. 4. These knife strips protrude above the surface of the material of the roller 1, 2 and thus form blades which cut material from the product for reducing in size. It has been found that in this embodiment the constriction can also be of semi-circular shape so that the passage opening 9 between the rollers 1, 2 can acquire a circular shape. Due to the cutting action a spherical product P is obtained. Fig. 5 shows a second embodiment wherein between the disc-shaped members 8 a number of saw-blades are disposed mutually adjacent, which saw-blades 12 can be provided on the periphery with blade-like toothings. The diameters of the saw-blades 12 moreover differ mutually such that a constriction form 7 can once again be obtained which can ultimately be circular, oval shaped or even arcuate, see the enlarged middle disc. The material of the product is also subjected to a cutting process here and not a grinding process. Fig. 6 shows a third embodiment wherein a number of pins are disposed in a circular shape on the disc-shaped members 8. The pins lying closest to the rotation shaft 1, 2 are the longest, while the pins decrease in length towards the outer periphery of the discs. The extremities of the pins 13 are provided with cutting faces which again exert a cutting action on the material of the product. By varying the length of the pins 13 in this manner a circular continuous hole 9 can be obtained as well as an oval-shaped hole as according to fig. 2. The invention is not limited to the above described embodiments, and it is possible to deviate from circular or oval-shaped openings in order to obtain any desired product with a revolutional shape, for example an arcuate shape.

Claims: Device for reducing peelable products (P) such as potatoes in size to a predetermined shape, consisting of at least one pair of mutually parallel rotatably driven reducing elements (1,2), the outer surface of each of which has at least one constriction (7) such that two oppositely situated constrictions (7) form a passage opening (9) between the elements (1,2) for the reduced product (P), characterized in that the constriction (7) in the outer surface of each reducing element is defined by knife-like protrusions (11;12;13) comprising cutting surfaces for cutting the products (P) to the predetermined shape. Device as claimed in claim 1, characterized in that the knife-like protrusions are formed by knife strips (11) radially extending from a rotatable shaft, each of said strips having a cutting edge which conforms to the predetermined shape of the product (P). Device as claimed in claim 1, characterized in that the knife-like protrusions are formed by teeth on mutually adjacent saw-blades (12) of different diameter arranged on a rotatable shaft (1,2). Device as claimed in claim 1, characterized in that the knife-like protrusions are formed by pins (13) which extend from a disc-shaped member (8) arranged on a rotatable shaft (1,2), said pins (13) being parallel to the rotatable shaft and having a decreasing length. Device as claimed in any of the preceding claims, characterized in that the passage opening (9) is round as seen in top view. Device as claimed in any of the preceding claims, characterized in that the element is constructed from two disc-shaped members (8) lying at a mutual distance, between which the knife-like protrusions (11;12;13) extend. Device as claimed in any of the foregoing claims, characterized in that a number of rotatable reducing elements are disposed mutually parallel, thus forming rollers (1,2). Device as claimed in any of the foregoing claims, characterized in that the elements and the rollers (1,2) are driven in the same rotational sense. Device as claimed in claim 8, characterized in that the peripheral velocity of the elements and the rollers (1,2) is disparate.

Inventors: BACKUS STEPHANUS MICHAEL MARIE, BACKUS, STEPHANUS MICHAEL MARIE
Applicants: BACKUS BEHEER BV, BACKUS BEHEER B.V.
Application year: 1993
Main classification: A23N7
IPC codes: A23N15, A23N7