The present invention relates to a sorting or batching arrangement of the kind where the items being worked with are fed forward on a more or less smooth conveyor, along which at one or two sides a series of receiving arrangements are placed in the form of collection containers or lead-out conveyors, in the following called receiving stations, and where for selective activation there are control elements in the form of movable sweeper elements which are arranged in a stationary manner but are controllable, and which by a movement transversely to the transport direction can bring about a sweeping-out of a given item to a selected receiving station. The sorting elements typically involved are purely pivotal sweeper arms, which from an axle bearing near the one edge of the conveyor extend in a passive normal position along with this edge, and which can thus be swung in to an active inclined position over the conveyor. By means of such a selective swinging-in, various forms of control influences can be imposed on an item passing on the conveyor. By a complete swinging-in in front of the item, this item will abut against the inclined sweeper arm, so that by the friction-based feeding on the conveyor the items will be forced to be displaced sideways out towards the associated receiving station, but the swinging-in can also be controlled in such a manner that that it is utilised dynamically for an actual sideways ejection of the item. All depending on the nature of the items, it can be important to distinguish between these modes of operation. However, it is an overriding and common condition that the swinging-in can be performed in a quick and reliable manner, not only so that the work in general can be carried out with a high capacity, i.e. with minimised distance between the items and maximised speed of conveyance of said items, but also so that the arms are able to exert the striking power necessary for active side ejection of the items. It is quite customary that the swinging movements are controlled by means of quick-acting air cylinders, which cooperate with a radial arm on the pivot axle of the respective sweeper arms. Hereby, a quite quick reaction can be ensured and the slight degree of sluggishness arising in these movement systems can be "compensated for" beforehand in the normally used computer controlling of the systems. In connection with deflection, ejection and the like of the items which are transported on a conveyor arrangement, in addition to the systems described by way of introduction there are various other arrangements described within the prior art. From US 6,536,580 Bl there is thus known a system for the distribution of packages, where packages on a conveyor can continue along the same path or be transferred to additional conveyors. With this system, use is made of a deflector unit where an arm can be set in four different positions by means of two linear actuators. With two of the positions, a package continues on the same conveyor, with a third position the package is led by the arm over to one of the additional conveyors, and with a fourth position the package is led over to the second of the additional conveyors. The actuators can be driven electromechanically by means of electromotors which are not described further. As will appear, the arm leads the items/packages in a certain direction while the arm is positioned in a static manner, i.e. the arm is not a sweeper arm which actively, i.e. by its own movement, shoves an item away from the conveyor. Furthermore, from US 2003/010682 Al a system is known for pushing bottles from a first conveyor over to a second conveyor running next to the side of the first conveyor. A sweeper arm is mounted on the spindle of a motor, so that the sweeper arm can be moved in over the conveyor. This motor is a synchronous motor, more precisely a synchronous motor of the servo type, with which the movement of the sweeper arm can be controlled. With this known system, a focal point is that the bottles must not overturn when swept out, which among other things is taken into account by the sweeper arm being arranged to hit the bottles in the vicinity of and immediately below the centre of gravity of the bottles. EP 0 850 862 A2 relates to an arrangement for pushing a series of glass articles from a conveyor into a cooling oven, where a plate can push a number of articles at the same time onto a mat in the oven. This plate is controlled in three directions by means of three servo-motors, so that the plate is guided in the direction of the conveyor by a first motor, in and out of the oven by a second motor, and in upwards and downwards direction by a third motor. The plate can hereby be pushed into the oven, and when the glass articles have reached in far enough, the plate can be withdrawn and raised, so that on its return the plate passes over the articles which are now fed forward on the conveyor, and so on. As will appear, this electrically activated movement arm is not associated with a sorting or batching arrangement such as that with the present invention, and the arm is also substantially different from a sweeper arm. US 4,585,613 A relates to a system for the sorting of fruit and vegetables, where the items are conveyed on tiltable trays, so that items to be sorted out can be tilted off. This can be implemented by a solenoid coil activating a release pawl which causes the tray to tilt. There is thus no mention of a feeding of items on a more or less smooth conveyor along which there are placed a series of receiving arrangements, and neither is any use made of selective activation of control elements in the form of movable sweeper arms, which by a movement transversely to the direction of conveyance can bring about a sweeping-out of a given item to a selected receiving station. CA 1 257 557 A relates to a deflector unit for bottles which are transported on a conveyor. As shown, the deflector unit has a flexible arm which at its one end is mounted, and which at the other end is connected to an additional arm. At its other end, this additional arm is arranged to be able to be displaced along the conveyor, so that the flexible arm will bend more or less in over the conveyor. With this prior art the actuation itself is effected by means of a pneumatic unit. US 6,220,421 Bl relates to a sweeper arm for packages which is described in two different embodiments, namely a first embodiment where the packages are pushed with an arm which is pivotally mounted around a horizontal axis above a conveyor path for packages, and a second embodiment where an arm is pivotally mounted around a vertical axis above the conveyor path. In both cases, the arm is activated by means of a motor and a crank arrangement, where the motor is not described further in the publication. In connection with the second embodiment, it is described that since individual couplings such as electromagnetic couplings can be arranged, several arms can be driven by a common drive unit. As will appear, the arm with which the packages are shoved is not associated with a sorting or batching unit as with the present invention, and the arm is also substantially different from a sweeper arm. It is an object of the invention to provide an improved sorting or batching machine. It is especially an object to provide such a machine which has an increased capacity and a required precision. It is a further object to provide such a machine which is especially suitable for use in the sorting and/or batching of food items and the like such as, for example, pieces of meat, fish etc. In connection with the invention, it has been found that various attempts to increase the capacity of the contemplated plants founder on a pronounced increase of a problem which beforehand is by no means unknown, namely that erroneous deliveries of items may arise which are consigned to a certain receiving station, but which however are led out to the preceding or the subsequent station, respectively to "faulty" delivery in between two stations. The picture that presents itself hereby is that there is a need for a more precise control of the sweeping-out function, and with the invention it has been found that this object will be achievable with continued use of the said sweeping arms merely providing that their movements are selectively controlled, for example by means of electric motors. Via an associated control unit, these motors can be programmed for execution of a momentary-controlled turning movement of the coupled sweeper arms via a simple drive engagement, e.g. a gearwheel connection, whereby new and very advantageous control and operation possibilities can be achieved. First and foremost, it is achieved that it will not be necessary for air to be conducted to the installation site, so that supply pipes, tubes or the like are avoided. Moreover, an advantage is achieved in that since no use of air is made for actuation, there will be less need for maintenance and the installation will be cheaper. An immediate benefit is that in the control sequence, it will no longer be necessary to take into account the sluggishness and sluggishness variation which inevitably arises in connection with the air-operated systems, including variations in the air pressure supplied. For example, with different forms of electromotor control, a precise and momentary mechanical reproduction of a control sequence, which is programmed into the associated control unit, can be reckoned with, and this condition alone will provide functional advantages with regard to the combination of high capacity and good delivery precision. To this can be added that these advantages can be reinforced in many other ways, e.g. by being able to program the control unit to selectively bring about different, item-related movement patterns for the sweeper arms, depending on whether it is most relevant for the given items to work with sliding deflection along a provisionally stable swung-in arm, or with dynamic ejection with determined force and/or speed from a swinging arm. It will even be possible that an item which with a considerable speed is fed forward towards an arm which has just been swung in, can hit the arm with a force which will induce a turning moment on the arm which is greater than that with which the motor initially retains the arm in its swung-in condition; the arm will hereby "yield forwards" for a damping of the abutment with the item, which can be desirable in connection with items which are larger or sensitive to impact, and the control can thus be tuned so that the arm will yield initially, but thereafter will quite quickly and gently accelerate the item in the sideways direction for precise delivery, regardless of whether this is effected by sliding deflection or by gentle ejection, i.e. with gradually increasing ejection effect of the arm. Precisely, with the use of, e.g., a step- or servomotors, it is possible to control both torque and speed, and this is utilisable to the highest degree in connection with the invention for the differentiating of the working mode of the arms. But such a control can also be achieved in connection with other kinds of electro-motors, which in practice can give more or less the same precise control, for example when use is made of asynchronous motors, which for example are controlled with the use of frequency converter techniques etc. It shall be noted that a particularly attractive solution can comprise an electromotor of the asynchronous type, which is used for the activation of a sweeper wing or arm. Hereby, a system which is particularly effective and economically- realisable can be achieved. For example, use can be made of standard asynchronous motors which can be coupled with encoders for achieving a desired control of the motor. Other embodiments where use is made of asynchronous motors also lie within the scope of the invention. It will be obvious that use can also be made of other types of electromotors. Moreover, yet a further preferred embodiment can comprise a worm gear which is coupled in between the activation, for example an electromotor and a sweeper wing or arm. A desired gearing can hereby be achieved in an attractive manner, and at the same time a self-locking of the system can also be achieved, understood in the sense that with given gearing ratios, the sweeper arm will not be able to be influenced for movement of an item on the conveyor against the torque of the motor. With a particularly simple manner of producing such a worm drive, the one part of the drive, for example the toothed part, can be configured on the sweeper arm itself, so that among other things an exceptionally compact construction is achieved. A further advantage can be obtained hereby, in that it will be possible to adapt the control function to the situation arising in practice, that although the items are perhaps fed forward with a more or less uniform and otherwise detectable mutual distance in the longitudinal direction of the conveyor, but on the other hand appear with positional deviations in the conveyor's transverse direction, which can result in appreciable precision problems with the prior art, especially with ejections of the items by impact, where the arm will hit a given item with different speed depending on whether the item has larger or smaller distance from the pivot axis of the arm. With the present invention there will be a possibility of detecting transverse position of the items with sensors or a vision equipment, and depending on this detection to activate a control function with which the item will be influenced in a suitable, differentiated manner, typically by increasing the speed of the arm the closer the item lies to the pivot axis of the arm. It is already known that in connection with apparatuses which must be able to handle items of different types, it can be desirable to operate with various adjustments of the function parameters of the sweeper arms, which normally involves quite troublesome mechanical setting and/or replacement work, and it will be understood that with the invention this will be replaceable by a simple selection of different control programmes, completely without mechanical intervention. Among things which can traditionally be adjusted or replaced are the sweeper arms themselves, which for various tasks can be rather angled or curved, and although in connection with the invention there can also be a need for precisely this replacement possibility, it will however generally apply that the need for replacement will be significantly reduced, for the reason that the individual types of arms can operate or be operated with a greatly increased function spectrum.

The drawings The invention will now be briefly described with reference to the drawing, in which fig. 1 illustrates different swinging-in sequences of sweeper arms in a batching machine according to one embodiment of the invention, fig. 2 is a corresponding illustration of a machine with sweeper arms of different embodiments, and fig. 3 shows a sweeper arm which is configured with an example of a part of a worm drive.

Example embodiments In fig. 1 a plan view of a conveyor 2 is shown on which items 4 are fed in positions registered in a not-shown control computer. Along with the conveyor 2 a number of receiving containers 6 are placed, opposite which respective sweeper arms 8 are mounted, each of which can be swung around an axle 10 controlled by an actuator 12. In fig. 1, these sweeper arms or separator arms 8 are shown in several different positions at the same time, i.e. in different degrees of swinging-in or swinging-out over the conveyor 2. The significance of this will be explained later. These arms take up a normal or rest position along with the edge of the conveyor opposite the containers 6, so that the items 4 can be fed freely on the conveyor, but when the control unit has allocated an item for a certain container 6, the arm 8 for precisely this container is activated to swing in over the conveyor belt to form an inclined sweeping wall which, by the feeding of the item along the conveyor belt, will force the item to slide out to the relevant container 6. Immediately thereafter, e.g. when the area of the belt carrying the item has reached forward to the position shown at P, the arm is controlled to effect a quick return swing, so that there can be free passage for the next item.

When the actuators 12 in accordance with the invention consist of electromotors, for example servo-/stepmotors, asynchronous motors, DC motors etc., the relevant swinging-in and out of the arms can be effected in a both quickly and very precisely controlled manner, so that the items 4 can be conveyed with relatively short distance between them. With certain kinds of items, it is relevant to influence the items for side ejection from the conveyor belt, and in fig. 1 it is indicated that with the used motor or actuator control this sequence can be carried out at different speeds (stroke profiles), in that the arms in the positions shown hatched are under quicker swinging- in than in the non-hatched positions. Thus, at the first arm 8 it is shown that at the last two positions the arm is moved more quickly than at the first three positions. At the second arm the angular speed is greater at the three last positions than at the two first positions. At the third arm the speed at the four positions where the arm is shown swung out over the belt is greater than at the start position, and at the last arm in the row the angular speed is more or less the same in all the positions shown. It will be understood that the speed profiles shown are only simple examples and that many different speed profiles can be envisaged. These can include an actual hitting effect or a more gentle throw-out effect with gradually increasing speed. In fig. 2 two deviating arm shapes 8a and 8b are shown, and at the right-hand side it is shown that the arm 8 c can alternatively be swung out from the same edge of the belt as that at which the receiving container 6 is placed. It is also shown that an item 4 in one and the same position in the longitudinal direction of the belt can possibly appear with different positions 4a, 4b in the transverse direction of the belt, whereby for an optimised control of the item it can be desirable to make use of respectively different stroke profiles in connection with a detection of the occurring transverse position of the item. This possibility exists precisely by the control according to the invention. In fig. 3 an example of a particularly compact construction of a worm drive for a sweeper arm 8 is shown, which at the one end is provided with a spindle hole 14 corresponding to the spindle 10 in fig. 1 and 2. In the material around this spindle hole 14, the sweeper arm 8 is configured over a part of the surface with obliquely-cut teeth 16 which correspond to a worm drive. If the spindle on an electromotor is configured with a worm, this can work directly on the shown teeth 16 so that the sweeper arm is turned in direct dependence of the revolutions of the motor spindle. As described above, and such as disclosed in the subsequent patent claims, the invention can be exercised in many different ways and with the use of different part elements, including electromotors of different types, such as synchronous and asynchronous motors, DC motors, stepmotors, servomotors etc., and use can be made of various forms of couplings and/or gearing arrangements, such as worm drives and the like.