The present invention relates to a device for orienting substantially spherical objects, such as onions, apples, peppers or cabbage.

Spherical products such as onions, apples peppers and cabbage are often processed mechanically. Such treatments include peeling or hollowing out. For this purpose such products have to be introduced with a predetermined orientation into the peeling machine. This introduction into a machine has to be carried out .precisely by hand, this being a task requiring great concentration of the person carrying out this work. Such great concentration is required because it is necessary to work regularly and quickly. It has been found that this placing work slows the peeling process and that inaccuracy results in much waste.

In order to obviate these drawbacks the present invention provides a device for orienting a substantially spherical object having an external characteristic suitable for orientation, such as a bulbous plant, pepper, apple or cabbage, comprising:

- a frame,

- at least three drivable rotation members arranged in the frame,

- drive means for driving the rotation members, and

- an orientation determining system for determining the orientation of the spherical object.

Such a device is able to orient the objects precisely and quickly in an orientation suitable for the desired treatments. Losses due to erroneous insertion of objects is hereby prevented.

A first preferred embodiment relates to a device wherein the orientation determining system comprises at least one camera for making recordings of the object. In-

formation is hereby obtained in advantageous manner for the purpose of determining the orientation of the object.

The orientation determining system preferably comprises a processing unit and a memory for processing recording information from the camera. Calculations can be performed by means of the processing unit on the basis of software for the purpose of determining the orientation and an appropriate rotation of the rotation members.

In a further preferred embodiment the device comprises an adjusting mechanism for adjusting the mutual distance between the rotation members. A plurality of different objects can hereby be oriented with one device. The rotation members preferably also comprise rotation wheels.

In a practical embodiment the rotation members comprise a rotation surface with a predetermined coefficient of friction. This coefficient can be suitably chosen in accordance with the surface of the object. It is possible to provide an exchangeable surface or exchangeable members or wheels.

A further embodiment comprises a transfer device for transferring the object to a treatment device. The obtained orientation is herein retained during transfer. It is further possible during orienting of the objects to take into account a known change in orientation caused by the transfer device.

It is further possible to provide a treatment device for treating the object in a desired orientation. This can be a per se known peeling device for onions.

The transfer device preferably comprises spring means for placing the object under bias in a treatment device. It hereby becomes possible for a spring unit to be arranged in a gripper of the transfer device, with which spring unit the object is placed under bias in an opening of the peeling machine. This prevents, among other things, an undesired rotation taking place after the placing.

The central axes of the rotation members are preferably ordered in one plane. A relatively simple calculation method for the rotations to be performed hereby becomes possible.

A further aspect of the present invention relates to a method for orienting a substantially spherical object with an external characteristic suitable for orientation, such as a bulbous plant, pepper, apple or cabbage, comprising steps for:

- placing the object on at least three drivable rotation members,

- determining the orientation of the object,

- determining the desired change in the orientation,

- rotating the rotation members on the basis of the desired change in the orientation.

In a preferred embodiment the step for determining the orientation of the object comprises steps for:

- making a recording by means of at least one camera,

- determining the position of external characteristics of the object on the basis of the recording,

- determining the orientation of the object on the basis of the relative position of the external characteristics of the object.

The method preferably further comprises steps for controlling the rotation of the rotation members so that the displacement vector has an upward directed resultant. Such methods provide advantages similar to those described in the foregoing with reference to the device.

Further advantages, features and details of the present invention will be elucidated on the basis of an embodiment wherein reference is made to the accompanying figures, in which:

- Fig. 1/6 shows a schematic side view of a first embodiment according to the present invention;

- Fig. 2/6 is a top view of the embodiment of fig. 1/6;

- Fig. 3/6 shows an isometric projection of the embodiment;

- Fig. 4/6 shows a block diagram of a part of the embodiment;

- Fig. 5/6 shows a flow diagram of an embodiment of a method according to the present invention;

- Fig. 6/6 is a side view of a further embodiment according to the present invention.

A first embodiment (fig. 1) according to the present invention relates to an orienting device 11 comprising three wheels 1, 2 and 3, of which the rotation axes lying in one plane are arranged in triangular position, and which are driven by drives 4, 5 and 6. A camera system 7, comprising a processing unit and a memory, determines the orientation of product 8 on the basis of geometric characteristics. This orientation is then translated by the processing system, not shown in the figure, into a combined drive pattern for the purpose of drives 4, 5 and 6 of wheels 1, 2 and 3.

Fig. 2/6 shows wheels 1, 2 and 3, of which the rotation axes lying in one plane have a triangular relation. The wheels are always driven in combination, so that the resultant displacement vector is directed upward. Due to combined actuation of wheels 1, 2 and 3 the product is forced into a determined direction of rotation.

Using adjusting means (not shown) the distance of the rotation axes can be adjusted so that products of a different size, such as onions, can be oriented.

Fig. 4/6 shows a block diagram of the orienting system. Camera 7 makes a recording of the product, in particular the onion, and transmits the image information to the processing unit. This processing unit 10 digitizes the image information. From this image information of the product the top or bottom (top or tail of the onion) is then

determined, one of which will be on view. Stated generally, the axis through the product is defined whereby the orientation of the product can be determined. From this orientation axis of the onion and the desired orientation the desired rotation of the product is calculated for the purpose of causing the product to assume the desired orientation.

This necessary rotation of the product is then translated into a pattern of rotation of the wheels so as to be able to bring about the desired rotation of the product. The drive of the wheels is then controlled in accordance with this pattern. The drives 4, 5 and 6 rotate wheels 1, 2 and 3 which cause the product to rotate to the desired position. The position of the onion is then recorded again by the camera for monitoring purposes or for the purpose of further correction of the orientation of the onion.

Fig. 5/6 shows schematically a preferred embodiment of a method for orienting the objects. In step 16 one or more recordings are made of an onion and, depending on the embodiment, these images are digitized by means of an A/D converter. In step 17 the orientation of the onion is determined by means of orientation determining means. A rotation profile is then defined in step 18, on the basis of which the rotation of the wheels is subsequently performed. This profile comprises data relating to the rotation of each of the wheels during orientation of the onion.

In step 19 the desired rotation of the onion is converted on the basis of the profiles into motor actuation instructions by means of suitable instruction compiling means. In step 20 the motors are then actuated by means of for instance a servo on the basis of the motor actuation instructions.

For placing of the onion in an onion peeling machine, gripper 9 of transfer arm 10 takes the onion out of

the orienting device 11 and the transfer arm displaces the onion to hole 12 in machine 13. The onion is then placed under spring pressure in the hole by the gripper so that the onion does not change orientation during placing.

The present invention is not limited to the description above. In the light of the description, different aspects of the described embodiments can be combined by the skilled person. The rights sought are defined by the appended claims.