WO1991007883A1

WO1991007883A1 - An apparatus for hollowing root vegetables

Info

Publication number: WO1991007883A1
Application number: PCT/DK1990/000315
Authority: WO
Inventors: Svend Persson
Original assignee: Danisco A/S
Priority date: 1989-12-04
Filing date: 1990-12-04
Publication date: 1991-06-13
Also published as: DK610789D0; AU6904791A

Abstract

An apparatus for hollowing potatoes and other differently shaped and/or sized tubers, fruits, root vegetables or the like comprises means (18, 20) for detecting the dimension of each plant part, means (19, 21) for forming a hollow space in each plant part, and control means (31) for controlling the movement of the forming means in response to dimension signals received from the detecting means, so as to adapt the inner dimensions of the hollow space being formed to the outer dimensions of the plant part. Thus, the hollow spaces being formed in the differently shaped and/or sized plant parts may be individually adapted to the shape and size of the plant parts in a mechanical automated process.

Description

AN APPARATUS FOR HOLLOWING ROOT VEGETABLES

The present invention relates to an apparatus for hollowing differently shaped and/or sized tubers, fruits, root vegetables or the like plant parts. Such plant parts comprise, e.g., apples, pears, oranges, lemons, melons, tomatoes, avocado pears, pine-apples, onions, potatoes, yam, garden turnips, and other edible plant parts.

It is known to hollow fruits, such as apples, melons, oranges, lemons and pine-apples, and to fill the hollow spaces of the fruits with fruit drinks, sweets, desserts, such as fruit sorbets, or other edible fillings. It is also known to hollow potatoes and other edible plant parts and to fill the hollow spaces with a meat product or other edible products. Because the size and shape of tubers, fruits, and root vegetables vary substantially, such plant parts have hitherto normally been hollowed by a manual operation, and an automated hollowing of such fruits or plant parts has been possible only in cases where a reasonable fraction of uniformly shaped and sized fruits or plant parts could be sorted out.

The present invention provides an apparatus for hollowing differently shaped and/or sized plant parts of the above type, said apparatus comprising means for detecting dimensions of each plant part, means for forming a hollow space in each plant part, and control means for controlling the movement of the forming means in response to dimension signals received from the detecting means, so as to adapt the inner dimensions of the hollow space being formed to the outer dimensions of the plant part. Thus, the hollow spaces being formed in the differently shaped and/or sized plant parts may be individually adapted to the shape and size of the plant parts in a mechanical automated process.

The detecting means for detecting shapes and sizes of the plant parts may be of any suitable type. As an example, the detecting means may comprise sensing means for sensing the dimensions of the plant parts in at least two different directions, which may extend at substantially right angles. Thus, for example, the maximum length and the maximum height of the plant part may be detected. In connection with some types of plant parts it may also be desirable to detect the maximum width of the plant part. The sensing means may comprise members which are movable into and out of engagement with the plant part to determine the dimension thereof. Alternatively,^" the detecting means may comprise a light Source and a photoelectric cell to determine the extension of the plant part in a certain direction. In some cases it may be desirable to measure not only the maximum dimension In a certain direction, but such dimension in two or more positions. Still more detailed information about the size and shape of a plant part may be obtained, if the detecting means comprises at least one camera for making a picture of each plant part, and means for digitizing said picture and for transmitting digitized picture signals to the control means. The control means may then control the movement of the means forming the hollow space very accurately, whereby the shape and size of the hollow space may be individually adapted to the outer shape and size of the plant part.

The detecting means may alternatively or additionally comprise a scanning device including a plurality of light sensitive means, such as light sensitive diodes, each providing a signal to the control means in response to the intensity of light received. Such a scanning device may detect not only the outer contour of the plant part being treated, but also the contour of a cut in case an outer surface slice or a top part has been cut from each plant part. The movement of the forming means may then be controlled not only on the basis of the outer contour or dimensions of a respective plant part, but also on the basis of the contour of the cut.

The light sensitive means may be arranged along a line, and the contour or the outer dimensions of each plant part may then be detected by the detecting means when the plant part is moved transversely to said line. Thus, the light sensitive means may be stationarily mounted, while the plant parts are moved transversely to the line of light sensitive means. In the preferred embodiment, however, the apparatus comprises means for moving the scanning device transversely to said line, so that the contour of the plant part may be detected, while the plant part is kept stationary.

According to the invention the forming means may comprise cutting means for cutting an outer surface slice or top part from each plant part. These cutting means may be of any suitable kind, such as a circular saw or an endless saw blade, and the cutting level of the cutting means" or saw blade may then be adjusted in response to the height of the plant part as measured by the detecting means. In order to exclude contamination of the plant parts being treated, the cutting means or saw blade is preferably continuously sterilized and flushed, for example by means of high pressure hot water jets, whereby possible micro-organisms on the cutting means are effectively killed. A hollow space opening into the cut surface may now be formed in the plant part.

The forming means may alternatively or additionally comprise an elongated cutting member having a shape corresponding substantially to the generatrix of the inner surface of the hollow space to be formed, and the cutting member may then be moved along a suitable path controlled by the control means so as to cut the desired hollow space having a shape and inner dimensions adapted to the outer shape and outer dimensions of the plant part being treated. Thus, a suitable combined translatory and rotative movement may be imparted to the cutting member so as to cut and loosen the plant material located inside the hollow space being formed. As an example, moving means may be provided for moving the cutting member along a directrix defined by the control means in response to the dimension signals received from the detecting means.

When the plant part -being treated is of a fresh and crisp consistency, the cutting member may have a sharp edge. However, when the plant parts are boiled or baked, tubers or vegetable roots, such as boiled or baked potatoes, the cutting member preferably comprises a shaped wire length, which may, e.g., be substantially J-shaped.

Preferably, the apparatus according to the invention further comprises means for filling the hollow space formed in each of the plant parts with an edible filling material, so that the hollowed plant part and the filling material received therein in combination form an improved food product. The control means may then control the filling means so that the amount of filling material filled into each hollow space is related to the volume of said space, whereby different, but individually adapted amounts are filled into the various hollowed plant parts.

In the preferred embodiment of the apparatus according to the invention, the detecting means and the forming means are located at various stations, and the plant parts may then intermittently and successively be moved to the various stations by means of a conveyor.

The convey.or means may then comprise a plurality of transverse, mutually spaced, substantially parallel separating walls defining therebetween plant part receiving spaces open at opposite ends.

Each of the plant parts may be retained in the desired position at each station in any suitable manner. In the preferred embodiment, however, at least one of said stations comprise retaining means movable into and out from the opposite end of said plant part receiving spaces so as to maintain the plant part therein in a desired position at the respective station.

The said stations may comprise a first detecting station including a first sensing device for detecting the maximum height of a plant part at said first detecting station and for transmitting a height signal to the control means. This first sensing device may be of the mechanical contacting type or may comprise light sensitive means. Thus, the first sensing device may comprise a light source and a light sensitive cell mounted vertically movable on either side of the conveyor means.

The said stations may also comprise a first forming section positioned downstream on the first detecting station and including a first cutting device for cutting a top slice from a plant part of said first forming station at a level determined by the control means in response to the height signal received from the first detecting means. Alternatively, the first detecting means may comprise a camera or scanning means for determining the vertical contour of the plant part, and the cutting level may then be determined so as to obtain a desired area of the cut.

The said stations may further comprise a second detecting station including a second detecting device for determining horizontal dimensions of a plant part at said second detecting station and for transmitting dimension signals to the control means. This second detecting device may comprise dimension-sensing members movable into and out of engagement with the plant part through the open opposite ends of the plant part receiving space located at the second detecting section. The second detecting device may alternatively or additionally comprise a camera or a scanning device including a plurality of light sensitive means for determining the horizontal contour of the plant part. Such scanning device may include a plurality of light sensitive means, such as light sensitive diodes, each providing a signal to the control means in response to the intensity of light received. The light sensitive means may then be arranged along a line, and the apparatus may further comprise means for moving the scanning device transversely to said line.

Said stations may also comprise a second forming station positioned downstream of the second detecting station and including a second cutting device for cutting an upwards open hollow space in each plant part at said second forming station, so that cut and loosened plant material remains in said hollow space, the movement of the cutting device being controlled by the control means in response to dimension signals received from the second detecting device.

As mentioned above, the hollow spaces are preferably formed in the plant parts moving along the conveyor so that they open at the top portions of the plant parts. This is for sanitary reasons because then the cut and loosened plant material located inside the hollow space formed by the forming means does not come into contact with the conveyor. In order to remove the loosened plant material from the hollow spaces formed, the apparatus according to the invention may comprise a tilting station located downstream of the second forming station and including a tilting device for tilting a plant part so as to remove cut and loosened plant material from the hollow space formed therein. The tilting device is preferably spaced from the conveyor, and each of the plant parts may then be transferred from the conveyor to the tilting device, and vice versa, by suitable transfer means. The tilting device may comprise suction means for retaining the plant part in its tilted position in which the loosened plant material falls out of the hollow space under the influence of gravity.

A control device for controlling the quality and condition of the plant parts with hollow spaces formed therein may be positioned downstream of the second forming station. The control device, which may for example comprise a camera, may determined whether the hollowed plant parts are suitable for further processing, for example for receiving an edible filling material. In case a plant part is found not to be suitable for further processing, it may be removed from the conveyor by suitable ejector means.

The invention will now be further described with reference to the drawings, wherein Fig. 1 is a perspective view of an embodiment of the apparatus according to the invention,

Figs. 2 and 3 illustrate in an enlarged scale the movement of a cutting member forming a hollow space in a baked potato, Fig. 4 is a perspective view showing part of a first modified embodiment of the apparatus shown in Fig. 1,

Fig. 5 is a digitized picture, which is taken by a camera, and on the basis of which a hollow space in the potato is formed, Fig. 6 is a perspective view showing part of a second modified embodiment of the apparatus shown in Fig. 1, Fig. 7 illustrates scanning of a topped or scalped potato, and

Fig. 8 is a perspective view of one end of a conveyor belt of the apparatus.

Fig 1 illustrates an apparatus for hollowing baked or cooked potatoes 10 and for filling the hollow spaces made in the potatoes with an edible filling material. The baked potatoes 10 are transported through the apparatus by means of a conveyor belt 11 which is passed over a driving roller 12 driven by an electric motor 13. The outer surface of the belt is provided with a plurality of mutually spaced, carrier plates or separating plates 14, which extend transversely to the longitudinal direction of the conveyor belt 11. The carrier plates or separating plates 14 define between each pair of adjacent plates a potato receiving space 15 open at opposite ends. The conveyor belt 11 transports the potatoes on Its upper run in a direction indicated by an arrow 16 from a loading station 17 at one end of the conveyor, where a baked potato 10 is manually or mechanically arranged in each of the potato receiving spaces 15. The conveyor belt 11 is driven intermittently by the electric motor 13 so as to transport the potatoes 10 through various stations so that each potato has a certain dwelling period at each station. Thus, the potatoes are moved through a height detecting station 18 where the height of each individual potato is measured, a top cutting station 19, where the top of each potato is cut off, a length detecting station 20, where the length of each potato 10 is detected, a hollow forming station 21, where an upwardly open hollow space is formed in each of the potatoes, a transfer station 22 for transferring each of the potatoes to and from a tilting station 23, which is arranged offset from the conveyor belt 11, and at which each potato is turned upside down to remove loosened potato material therefrom, and to filling stations 24 and 25 for filling edible materials into the hollowed potatoes. The conveyor belt may further move the hollow, filled potatoes thus produced through a freezing station and to a packing station, not shown.

The height detecting station 18 comprises a bracket 26 in which a light source 27 and a photoelectric cell 28 are arranged oppositely on either side of the belt 11. The bracket 26 and the light source 27 and the photoelectric cell 28 mounted thereon may be moved vertically upwards and downwards by means of a screw spindle 29 driven by an electric motor 30. The height of each potato 10 is determined by determining the position of the bracket 26, at which the top of the potato just interferes with the light beam passing from the light source 27 to the photoelectric cell 28. For each individual potato 10 a height signal is transmitted from the station 18 to an electronic control device 31 controlling the operation of the apparatus. The control device may comprise a programmable process computer.

The top cutting station 19 comprises an endless saw blade 32 passed around a pair of discs one of which is driven by electric motor 34. The endless saw blade 32 and the discs 33 are mounted within a housing 35. This housing 35 is displaceable in the longitudinal direction of the conveyor belt by means of a pneumatic cylinder 36, and the housing is also vertically displaceable by means of pneumatic cylinders, not shown. The vertical position of the housing 35 and the endless saw blade contained therein is controlled by the control device 31 based on height detecting signals received from the height detecting station 18. When a potato 10 is dwelling at the top cutting station 19, the housing 35 and the saw blade 32 contained therein are moved in the longitudinal direction of the conveyor belt 11 by means of the cylinder 36, whereby the upper run of the saw blade cuts of a top slice 37 from the potato 10. The vertical position of the saw blade 32 is adjusted in response to the height of the individual potato 10, so that the top slices 37 cut from all of the potatoes will be of substantially the same thickness.

While a potato 10 is dwelling at the top cutting station 19 it is retained in position during the cutting process by means of pair of V-shaped retaining members 38 each mounted on an arm 39, which is movable transversely to the conveyor belt 11 by means of a pneumatic cylinder 40. Thus, when a potato 10 is dwelling at the cutting station 19, the retaining members 38 are moved into retaining engagement with the potato by means of the cylinders 40, and in order to ensure a substantially uniform abutment pressure, this abutment pressure may be determined by the bias of spring means. Now, the top slice 37 may be cut from the potato by means of the saw blade 32, and the retaining members 38 may be moved out of engagement with the potato and into engagement with the next potato which has now been advanced to the station 19. The top slices 37 cut from the potato 10 may be removed therefrom by means of an ejecting member 41 which may be moved transversely to the conveyor belt so as to throw a top slice cut from a potato 10 into a collecting container 43. For sanitary reasons, the saw blade 32 is continuously rinsed by hot water jets from a pair of oppositely arranged nozzles 32' positioned on either side of the saw blade.

The topped or scalped potatoes are moved from the top cutting station 19 to the length detecting station 20. A potato 10 dwelling at the length detecting station 20 is gripped between a pair of V- shaped abutment members 44, which may be moved into and out of abutting engagement with the potato by means of pneumatic cylinders 45. An optic or magnetic position sensing device 46 senses the position of the piston rod 47 of at least one of the cylinders 45, when the abutment members 44 are in contact with the potato. A corresponding signal indicating the length of the potato in question is transmitted to and stored by the control device 31. When the potatoes have passed the detecting station 20 they proceed to the hollow forming station 21, where each potato is gripped by V-shaped retaining members 48 operated by pneumatic cylinders 49. The retaining members 48 have a shape and function similar to the shape and function of the retaining members 38 and the top cutting station 19. Thus, the retaining members 48 serve to retain the potato in a desired position while a hollowing operation is being performed.

The hollow forming station 21 further comprises a hollow forming or cutting apparatus 50. The apparatus 50 comprises a cutting or forming tool 51 which in the embodiment shown is a substantially J-shaped member made from hardened steel wire. The cutting tool 51 may be rotated about its axis by an electric or pneumatic motor 52. The cutting tool 51 and its motor 52 are mounted at one end of a pair of horizontal guiding rods 53 extending transversely to the conveyor belt 11 and through bores in a first supporting block 54 so as to be displaceable in relation to the block 54. A pneumatic cylinder 55 is mounted on the other ends of the rods 53, and the outer end of the piston rod of the cylinder 55 is connected to the supporting block 54 so that the cutting tool 51 may be moved in a direction transversely to the conveyor belt 11 by means of the cylinder 55. The first block 54 is fastened to the upper ends of a pair of vertical guiding rods 57 extending through bores in a second supporting block 58 so that the blocks 54 and 58 may be moved vertically in relation to each other. Such vertical movement may be performed by means of a vertically extending pneumatic cylinder 59 having its piston rod 60 connected to the bottom side of the first supporting block 54. A second pair of horizontal guiding rods 61 extends in the longitudinal direction of the conveyor belt 11 through bores formed in the second supporting cylinder 58. A pneumatic cylinder 62 is connected to the guiding rods 61 at one end thereof, and the piston rod 63 of the pneumatic cylinder 62 is connected to the second supporting block 58, so that the block 58 may be moved horizontally in the longitudinal direction of the conveyor belt 11 by operating the pneumatic cylinder 62. It is understood that the cutting tool 51 may be rotated about its own axis by means of the rotor 52 and by operating the cylinders 55, 59, and 62 the cutting tool may at the same time be moved along any of three axes extending at mutually right angles and being represented by the axes of the said cylinders. Furthermore, any of these movements may be controlled by the controlling device 31 on the basis of stored signals previously received from the detecting station 20 and relating to the same potato 10 as that now being processed at the hollow forming station 21.

When an upwardly open hollow space has been formed in each of the potatoes at the station 21 in a manner which will be described more in detail below with reference to Figs. 2 and 3 the hollowed potatoes with the cut, loosened potato material proceed to the transfer station 22, where each potato is gripped at opposite ends by a pair of V-shaped gripping members 64, which are operated by means of a pair of pneumatic cylinders 65. The gripping device comprising the gripping members 64 and the pneumatic cylinder 65 is mounted on a block-shaped member 66, which may slide along a pair of guiding rods 67 extending above and substantially at right angles to the upper run of the conveyor belt 11. The block 66 and the gripping device 64, 65 may be moved along the guiding rods 67 by means of a pneumatic cylinder 68. Thus, the gripping device may be moved between one end position in which the gripping device may grip or release a potato 10 at the conveyor belt 11 and another end position, in which the gripping device may release or grip a potato positioned on a suction member 69 arranged at the tilting station 23. The suction member 69 defines a suction opening 70 therein communicating with a vacuum source, not shown, via a vacuum tube 71 including a valve 72.

Each potato is transferred from the conveyor belt 11 to the suction member 69 by means of the gripping device 64, 65. When the potato is positioned on and supported by the suction member 69, the valve 72 is opened, whereby the potato is sucked into engagement with the suction member 69. Now, the suction member 69 and the potato supported thereby is turned upside down by means of an actuating device 73 such as an electric or pneumatic motor, and a gear mechanism 74. By this tilting of the potato the loosened material 75 falls down into a collecting container 76. When the suction member 69 has been returned to its starting position, the emptied, hollowed potato is returned to the conveyor 11.

The hollowed potatoes which have been emptied for loosened potato material, and which have a substantially uniform wall thickness now proceed to the filling station 24, where a first filling material 77, which may comprise the potato material 75 in a mashed condition and one or more meat products and/or taste substances, is fed into the upwardly open hollow space of each potato through a spout 78. A second filling material or a topping 79 is applied to each potato at the filling station 25 through a spout 80.

As described above, the size of the hollow space or cavity formed in each of the potatoes 10 is dependent on the dimensions of each Individual potato as measured at the stations 18 and 20, so that the wall thickness of the hollowed potatoes is substantially uniform. The potatoes used by have been screened so that they have substantially the same width, while the length and height may vary within certain limits . As illustrated in Figs . 2 and 3 , the forming or cutting tool 51 is initially forced downwardly through the potato mass along a transverse centre line 81. Thereafter the shaft of the tool 51 is moved along a closed path 82, which is positioned inside the contour of the top slice cut with a predetermined, substantially uniform spacing therefrom. The tool is simultaneously rotated o through 360 so that the free end of the tool will always point at the centre of the potato. However, in order to be sure that the material 75 cut out is sufficiently loosened, the tool 51 is further rotated a small angle in relation to the centre line 81, whereby the material 75 is lifted when the tool 51 is moved upwardly out of the hollow space formed as shown in Fig. 3.

It should be understood that some of the operations described above could be manually or manually controlled. In the preferred embodiment, however, most of or all of the operations of the various devices and parts are controlled and interrelated by the control device or computer 31.

In the modified embodiment shown in Fig. 4 the devices for determining the dimensions of the individual potatoes have been supplemented with a camera 83 for making a top view picture of each of the scalped, but not yet hollowed potatoes. An example of such a top view picture is shown in Fig. 5. On the basis of such a picture the control device 31 may control the movement of the cutting tool 51 so that hollowed potatoes having a substantially uniform wall thickness are obtained. Thus, the camera 83 may replace the length detecting station 20, if desired. A second camera 84 may be arranged downstream of the hollow forming station 21 for checking the hollowed potatoes before and/or after removing the loosened potato mass 75. Hollowed potatoes which may be found to have not allowable deficiencies may be sorted out manually or automatically. A screen 85 may be connected to the control device for showing the picture taken by any of the cameras so that an operator may watch for possible deficiencies. If desired, a further camera may be used for making a side view picture of the potatoes. Such camera could replace the height detecting station 18.

Fig. 6 shows a further modified embodiment of the apparatus according to the invention. This embodiment comprises a light unit 86 including a pair of mutually spaced light sources 87, such as neon tubes, extending substantially parallel with the conveyor belt 11. A scanning camera, which is positioned between the light sources 87 and immediately above the conveyor belt 11 may be moved reciprocatingly along the conveyor belt by means of a pneumatic cylinder 89. The camera 88 comprises light sensitive means, which may comprise a plurality of light sensitive diodes positioned along a line extending transversely and preferably substantially at right angles to the conveyor belt 11. Each of the diodes may generate a signal in response to the intensity of the reflected light received from the upper surface of the scalped potato 10 being scanned. These ^'light intensity signals are transmitted to the computer 31. It may be desired to activate the light diodes so that each of the potatoes 10 is scanned along a plurality of equidistantly spaced lines 89_t(Fig. 7). This may, for example, be obtained by means of a ruler or scale 90 and a fork-shaped photoelectric sensing device 91 embracing the ruler and being movable therealong and in relation thereto. The ruler 90 or the sensing device 91 may be connected to and movable together with the camera 88. A further sensing device 92 may be adapted to generate a signal when the camera is in a suitable position to start scanning of a potato 10.

Fig. 7 illustrates the outer contour of a potato 10 in a top plan view and the contour 94 of the top slice cut. It is understood that based on the signals received from the linearly arranged diodes, the computer 31 may determine the points 95 of Intersection between the lines 89«,and the outer contour 93 of the potato as well as the points 96 of intersection between the lines 89*and the contour 94 of the cut. Thus, the computer 31 will receive information about the outer contour of the potato and the contour of the top slice cut as well as the mutual positions of these curves. The signals received from the camera 88 may be evaluated by the computer 31, and if they are found to be erroneous, the computer may decide not to use the data received from the camera 88 but to rely only on the length signal received from the sensing device 46. Because each of the potatoes 10 is scanned by the camera 88, a few steps upstream of the hollow forming station 21 the information received from the camera 88 and/or the sensing device 46 is stored until the potato in question reaches the station 21. The movement of the cutting or forming tool 51 may then be controlled on the basis of the information stored. It is also envisaged that the movements of the cutting tool 51 may be controlled by means of ultrasonic wall thickness scanning equipment.

SUBSTITUTE SHEET t$A/sε The intensity of the light sources 87 may gradually decrease. Therefore, the intensity of the light should preferably be checked from time to time, and the system could then be readjusted, if necessary.

In a preferred embodiment the camera 88 comprises 2048 light sensitive diodes arranged along a line, and during scanning of a potato 10, these diodes are activated each time the camera has been moved 2 mm along the conveyor belt 11. This means that the mutual spacing of the lines 8 U,will be about 2 mm.

As shown in Fig. 8, a rotating brush 97 for brushing and cleaning the conveyor belt 11 may be arranged below the lower run of the belt at one end thereof. The brush 97, which is driven by a motor 98 through a gear box 99, may be surrounded by curved guard plates 100.

Example.

Potatoes 10 to be processed in an apparatus as that described above with reference to Figs. 6-8 were screened so that their dimensions were within the following ranges: Length 86-125 mm, height 40-50 mm, width 60-80 mm. The position of the saw blade 32 is controlled by the control device 31 bases on the height signals received from the height detecting station 18 so that the top slice 37 cut from each potato is about 30 mm. The cutting tool 51 is made from a wire having a diameter of 0.6 mm, and the movements of the tool are controlled by the computer 31 along a closed path 82 which is positioned about 8 mm inside the contour 94 of the top slice cut. The hollowed potatoes have a minimum wall thickness of about 6 mm.

In about 20% of the cases the information received by the computer from the camera 88 are found not to be reliable, and the cutting tool 51 is then moved along a closed path selected from a plurality of stored, emperically collected paths, based on signals from the length sensity device 46. The camera system used is of the type marketed under the trade name "SCANLINE 500 vision system" by Scan Micro , Abyhøj , Denmark.

SUBSTITUTE SH ET ESA/SB ^• The finished, hollowed potatoes all have a clean cut inner wall surface, and the minimum wall thickness in each potato is sufficient to allow the potato to proceed th the filling station 24.

It should be understood that various changes and modifications of the apparatus described above may be made within the scope of the present invention. As an example, the saw blade 32 and the cutting tool 51 may be replaced by other kinds of cutting devices, when other kinds of fruits or root vegetables are processed in the apparatus.

Claims

1. An apparatus for hollowing differently shaped and/or sized tubers, fruits, root vegetables or the like plant parts, said apparatus comprising means for detecting dimension of each plant part, means for forming a hollow space in each plant part, and control means for controlling the movement of the forming means in response to dimension signals received from the detecting means, so as to adapt the inner dimensions of the hollow space being formed to the outer dimensions of the plant part.

2. An apparatus according to claim 1, wherein said detecting means comprise sensing means for sensing the dimension of the plant part in at least two different directions.

3. An apparatus according to claim 2, wherein said directions mutually extend at substantially right angles.

4. An apparatus according to any of the claims 1-3, wherein said detecting means comprise at least one camera for making a picture of each plant part, and means for digitizing said picture and for transmitting digitized picture signals to the control means.

5. An apparatus according to any of the claims 1-3, wherein the detecting means comprise a scanning device including a plurality of light sensitive means each providing a signal to the control means in response to the intensity of the light received.

6. An apparatus according to claim 5, wherein the light sensitive means comprise light sensitive diodes.

7. An apparatus according to claim 5 or 6, wherein the light sensitive means are arranged along a line, the apparatus further comprising means for moving the scanning device transversely to said line.

8. An apparatus according to any of the claims 1-7, wherein said forming means comprise cutting means for cutting an outer surface slice from each plant part.

9. An apparatus according to claim 8, wherein the cutting means comprise an endless saw blade.

10. An apparatus according to claim 9, further comprising means for continuously sterilizing said endless saw blade.

11. An apparatus according to claim 10, wherein said sterilizing means comprise high pressure hot water nozzles.

12. An apparatus according to any of the claims 1-11, wherein the forming means comprise an elongated cutting member having a shape corresponding substantially to a generatrix of the inner surface of the hollow space to be formed.

13. An apparatus according to claim 12, further comprising moving means for moving said cutting member along a directrix defined by the control means.

14. An apparatus according to any of the claims 1-13, wherein said plant parts are boiled or baked potatoes or similar root vegetables.

15. An apparatus according to any of the claims 12-14, wherein the cutting member comprises a shaped wire length.

16. An apparatus according to any of the claims 1-15, further comprising means for filling said hollow space of each of said plant parts with an edible filling material.

17. An apparatus according to claim 16, wherein said control means are controlling said filling means, whereby the amount of filling material filled into each hollow space is related to the volume of said space.

18. An apparatus according to any of the claims 1-17, wherein the detecting means and the forming means are located at various stations, the apparatus further comprising conveyor means for intermittently and successively transporting the plant parts to these stations.

19. An apparatus according to claim 18, wherein the conveyor means comprise a plurality of transverse, mutually spaced, substantially parallel separating walls defining therebetween plant part receiving spaces open at opposite ends.

20. An apparatus according to claim 19, wherein at least one of said stations comprise retaining means movable into and out from the opposite ends of said plant part receiving spaces so as to maintain the plant part therein in a desired position at the respective station.

21. An apparatus according to any of the claims 18-20, wherein said stations comprise a first detecting station including a first sensing device for detecting the maximum height of a plant part at said first detecting station and for transmitting a height signal to the control means.

22. An apparatus according to claim 21, wherein the first sensing device comprises a light source and a light sensitive cell mounted vertically movably on either side of the conveyor means.

23. An apparatus according to claim 21 or 22, wherein said stations comprise a first forming station positioned downstream of the first detecting station and including a first cutting device for cutting a top slice from a plant part at said first forming station at a level determined by the control means in response to the height signal received from the first detecting means.

24. An apparatus according to any of the claims 18-23, wherein said stations comprise a second detecting station including a second detecting device for determining horizontal dimensions of a plant part at said second detecting station and for transmitting dimension signals to the control means.

25. An apparatus according to claim 24, wherein said second detecting device comprises dimension-sensing members movable into and out of engagement with the plant part through the open opposite ends of the plant part receiving space located at the second detecting station.

26. An apparatus according to claim 24 or 25, wherein said second detecting device comprises a camera.

27. An apparatus according to claim 24 or 25, wherein said second detecting device comprises a scanning device including a plurality of light sensitive means.

28. An apparatus according to any of the claims 24-27, wherein said stations comprise a second forming station positioned downstream of the second detecting station and including a second cutting device for cutting an upwards open hollow space in each plant part at said second forming station, so that cut and loosened plant material remains in said hollow space, the movement of the cutting device being controlled by the control means in response to dimension signals received from the second detecting device.

29. An apparatus according to claim 28, wherein said stations comprise a tilting station located downstream of the second forming station and including a tilting device for tilting a plant part so as to remove cut and loosened plant material from the hollow space formed therein.

30. An apparatus according to claim 29, wherein the tilting device is spaced from the conveyor means, the tilting station further comprising transfer means for transferring a plant part from the conveyor means to the tilting device and vice versa.

31. An apparatus according to any of the claims 28-30, further comprising a control station located downstream of the second forming station and including a control device for controlling the quality and condition of a plant part with a hollow space formed therein.

32. An apparatus according to claim 27, wherein the control device comprises a camera or scanning device.

33. An apparatus according to any of the claims 28-32, further comprising a filling station arranged downstream of the second forming station and including at least one filling device for filling edible filling material into the hollow space of plant parts passing the filling station.