Filling machine

Abstract: A machine and process for filling a product (13) volumetrically which comprises introducing the product into a hopper (12), recording the level of the product (13) in the hopper (12) and transmitting the recorded information to a computer (18), conveying an empty chamber (19) to a position beneath the hopper (12), automatically adjusting the volume of the empty chamber (19) and filling the empty chamber (19) with the product (13) conveying the filling chamber (19) away from the hopper (12) and discharging the product (13), recording the weight of the discharged product (13) and transmitting the recorded weight to the computer (18), the automatic adjustment of the volume of the empty chamber (19) being based on the recorded imformation transmitted to the computer (18).

Description: The present invention relates to a volumetric filling machine, more particularly for solid and semi-solid or viscous products. Known volumetric filling machines are disclosed in DE-A-4 033 582 and GB-A- 2 134 089. DE-A-4 033 582, which forms the basis for the two-part form of claims 1 and 9, relates to a bulk material portion dispensing arrangement dosing predefined weight and comprising one weight dosing device arranged after a volume dosing device allowing adjustment of the chamber volume. GB-A-2 134 089 discloses a filling machine, which in the case of necessity for correction of the dose discovered by an variation in the weight of a filled container, can alter the delivered dose. A further example of a filling machine is disclosed in DE-A-3 120 017 describing a machine having a rotating dosing drum with measure chambers. This machine does, however, not has chambers which are automatically adjustable to a predetermined set volume. We have devised a volumetric filler in which the volume of the chamber is automatically adjusted to a predetermined set volume before filling and gives a very precise volume dosing, and further more has a very compact construction. Accordingly, the present invention provides a volumetric filling machine comprising a) a hopper for containing a product, b) sensor means for recording the level of the product in the hopper c) at least one chamber d) means for conveying an empty chamber to a position beneath the hopper for filling with product, e) means for conveying a filled chamber away from the hopper for discharging the product, f) a computer adapted to receive the recorded information (b), characterised in that the volumetric filling machine further comprises weighing means for recording the weight of product discharged from a filled chamber, which recorded information the computer is adapted to receive, and means adapted to be activated by the computer based on the recorded information, for automatically adjusting the volume of an empty chamber before filling with the product, and in that the chamber comprises a vessel surrounded at its periphery by a contacting wall in which it is adapted to slide longitudinally so that the upper edge of the vessel lies at a position level with or at a determined distance below the upper surface of the contacting wall. The sensor means for recording the level of the product in the hopper may be for instance, one or more photocells. The volume of the chamber comprises the volume within the vessel and any volume above the upper edge of the vessel bounded by and extending to upper surface of the contacting wall and the longitudinal sliding of the vessel within the contacting wall enables the volume of the chamber to be adjusted. The interior surface of the vessel is preferably smoothly curved and free from angles and the vessel is preferably semi-spherical. Advantageously, there are a plurality of chambers e.g. from 2 to 20 which pass consecutively beneath the hopper. The means for conveying an empty chamber to the hopper and for conveying a filled chamber away from the hopper may be an endless conveyor belt but preferably it is provided by a circular drum with a plurality of chambers, conveniently from 3 to 12, formed in the periphery. Advantageously, a fixed cover plate is positioned adjacent that part of the periphery of the drum conveying filled chambers before discharge. When the chambers are conveyed in the periphery of a circular drum, they are preferably spaced regularly around the periphery. Conveniently, the chambers are filled with the product when at the apex of the drum and are emptied when positioned at the base of the drum. Conveniently, a reciprocating knife is positioned beneath the lower end of the hopper which is adapted to separate the product in a filled chamber from that in the hopper. The weighing means for recording the weight of product discharged from a filled container may be, for instance, a check weigher. The means adapted to be activated by the computer for automatically adjusting the volume of an empty chamber comprising a vessel surrounded at its periphery by a contacting wall may be a key whose cross sectional area increases from the base to the head, passing horizontally through one side of the contacting wall and beneath the vessel, whose position may be adjusted along its longitudinal axis to cause the vessel to ascend or descend within the wall thus causing the volume of the chamber to decrease or increase respectively. The adjustment of the position of the key may be performed by a fixed motor activated by the computer. Vacuum means may be present to aid filling of the chamber and pressure means such as compressed air may be used to aid the discharge of the product from the filled chamber. The machine of the present invention may be used for filling products of suitable particle size such as vegetables, fish, meat, rice, spaghetti or French fries etc. The present invention also provides a process for filling a product volumetrically which comprises introducing the product into a hopper, recording the level of the product in the hopper and transmitting the recorded information to a computer, conveying an empty chamber to a position beneath the hopper, automatically adjusting the volume of the empty chamber and filling the empty chamber with the product, conveying the filled chamber away from the hopper and discharging the product, characterised in that the weight of the discharged product is recorded and transmitted to the computer, the automatic adjustment of the volume of the empty chamber being based on the recorded information transmitted to the computer, and in that the chamber to be positioned beneath the hopper comprises a vessel a vessel surrounded at its periphery by a contacting wall in which it is adapted to slide longitudinally so that the upper edge of the vessel lies at a position level with or at a determined distance below the upper surface of the contacting wall. The present invention will now be further illustrated by way of example only with reference to the accompanying drawings in which Figure 1 represents a diagrammatic transverse section through a filling machine, and Figure 2 represents a sectional view along the line A-A in Figure 1. Referring to the drawings, the filling machine comprises a circular drum generally designated 10 adapted to revolve in the direction of the arrow in Figure 1 driven by means of motor (not shown) driving a cog wheel 11 and guided by rollers 11a, 11b, positioned beneath a hopper 12 containing potato pieces 13. Photocells 14, 15, 16, 17 record the level of the potato pieces in the hopper and a computer 18 is adapted to receive this recorded information. In the periphery of the circular drum 10 are eight cylindrical openings 19 surrounded by walls 20 the axes of which are separated by an angle of 45° Slidably mounted within each cylindrical opening 19 is a semi-spherical vessel 21. Below the base of each semi-spherical vessel, a slot 22 is present in the wall 20 extending between the lateral walls of the drum 10 and within each slot 22 is an adjustable key 23 whose cross-sectional area increases from its base 24 to its head 25, and secured to one of the lateral walls of the drum by means of an extension spring 26. A fixed pulse motor 27 positioned adjacent the apex of the drum controls a reciprocating pusher 28 by means of a rotating screw 33, the pusher 28 being adapted to push the head 25 of the adjustable key 23 into the appropriate position. The volume of the semi-spherical vessel bounded by and extending to the upper surface of the wall 20 constitutes the chamber 29. Pipe means 30 are present for generating a vacuum or pressure to aid in filling or discharging respectively the chambers 29. A cover plate 31 is provided around that part of the periphery of the drum carrying the filled chambers 29. Between the hopper and the chamber at the apex of the drum is a reciprocating knife 32. Drainage holes 34 are present in the wall 20 to admit compressed air or vacuum conditions into the chamber 29 via pipe 30. In operation, potato pieces 13 are fed to the hopper 12 and the level in the hopper is recorded by the photocells 14, 15, 16, 17, this information being used to adjust the present volume in the chamber 29 and being fed to the computer 18 which is programmed for a predetermined weight. The drum 10 is caused to rotate by a motor (not shown) and the cog wheel 11 until a chamber 29 is positioned immediately below the hopper 12, the lower end of which is closed by the knife 30 whereupon the drum stops and the motor 27 causes the pusher 28 by means of the rotating screw 33 to press the adjustable key 23 the appropriate distance to the left in Figure 2 to cause the vessel 21 to ascend within the wall 20 until the chamber 29, has the required volume. The reciprocating knife 32 retracts and potato pieces 13 fall into the chamber 29 aided by the vacuum generated through the drainage holes 34 and the pipe 30 until it is full whereupon the reciprocating knife 32 advances to cut off the product within the filled chamber. The drum restarts and the filled chamber travels with the rotating drum 10 covered by the cover plate 31 until it reaches the base of the drum just beyond the termination of the cover plate where the drum stops and the potato pieces 13 are discharged into a container on a conveyor by gravity aided by compressed air flowing through the pipe 30 into the chamber 29 via the drainage holes 34. The weight of the potato pieces discharged is recorded by a check weigher (not shown) which is positioned after the filling machine on the conveyor transporting the filled containers and the information is fed to the computer 18. The weight recorded by the check weigher indicates whether the filling has been correct. Too high a weight indicates that the chamber volume should be decreased - and vice versa. The hopper is fed with more potato pieces and, based on the information received from the photocells 14, 15, 16, 17 and the weight of the discharged potato pieces, the computer activates the motor 27 to cause the pusher 28 to adjust the position of the key 23 to the right or the left so that the volume of the chamber 29 positioned beneath the hopper 12 is adjusted to the desired value. After being filled with potato pieces, the filled chamber moves away from the hopper and the next empty chamber is conveyed to a position beneath the hopper where the process is repeated. The discharged potato pieces are fed into containers travelling below the circular drum on a conveyor belt. The drum may rotate at a speed sufficient to enable the filling of up to 80 cups/minute.

Claims: A volumetric filling machine comprising a) a hopper (12) for containing a product (13), b) sensor means (14,15,16,17) for recording the level of the product in the hopper (12) c) at least one chamber (29) d) means for conveying an empty chamber (29) to a position beneath the hopper (12) for filling with product (13), e) means for conveying a filled chamber (29) away from the hopper (12) for discharging the product (13), f) a computer (18) adapted to receive the recorded information (b), characterised in that the volumetric filling machine further comprises weighing means for recording the weight of product (13) discharged from a filled chamber (29), which recorded information the computer (18) is adapted to receive, and means adapted to be activated by the computer (18) based on the recorded information, for automatically adjusting the volume of an empty chamber before filling with the product (13), and in that the chamber (29) comprises a vessel (21) surrounded at its periphery by a contacting wall (20) in which it is adapted to slide longitudinally so that the upper edge of the vessel (21) lies at a position level with or at a determined distance below the upper surface of the contacting wall (20). A machine according to claim 1 wherein the vessel (21) is semi-spherical. A machine according to claim 1 wherein the means for conveying an empty chamber (29) to the hopper (12) and for conveying a filled chamber (29) away from the hopper (12) is provided by a circular drum (10) having a plurality of chambers (29) formed in the periphery of the circular drum (10). A machine according to claim 3 wherein the number of chambers (29) formed in the periphery of the circular drum (10) is from 3 to 12. A machine according to claim 1 wherein a reciprocating knife (32) is positioned beneath the lower end of the hopper (12), which is adapted to separate the product (13) in a filled chamber (29) from that in the hopper (12). A machine according to claim 3 wherein a fixed cover plate (31) is positioned adjacent that part of the periphery of the drum (10) conveying filled chambers (29) before discharge. A machine according to claim 1 wherein the means adapted to be activated by the computer (18) for automatically adjusting the volume of an empty chamber (29) is a key (23) whose cross sectional area increases from the base to the head, passing through one side of the drum wall and beneath the vessel (21), whose position may be adjusted along its longitudinal axis to cause the vessel (21) to ascend or descend within the contacting wall (20). A machine according to claim 7 wherein the adjustment of the key (23) is performed by a fixed motor (27) activated by the computer (18). A process for filling a product volumetrically which comprises introducing the product (13) into a hopper (12), recording the level of the product (13) in the hopper (12) and transmitting the recorded information to a computer (18), conveying an empty chamber (29) to a position beneath the hopper (12), automatically adjusting the volume of the empty chamber (29) and filling the empty chamber (29) with the product (13), conveying the filled chamber (29) away from the hopper (12) and discharging the product (13), characterised in that the weight of the discharged product (13) is recorded and transmitted to the computer, the automatic adjustment of the volume of the empty chamber (29) being based on the recorded information transmitted to the computer (18), and in that the chamber (29) to be positioned beneath the hopper (12) comprises a vessel (21) a vessel (21) surrounded at its periphery by a contacting wall (20) in which it is adapted to slide longitudinally so that the upper edge of the vessel (21) lies at a position level with or at a determined distance below the upper surface of the contacting wall (20).

Inventors: WADELL LARS GUSTAF ALBERT, WADELL, LARS GUSTAF ALBERT
Applicants: FRISCO FINDUS AG, FRISCO-FINDUS AG
Application year: 1992
Main classification: B65B3
IPC codes: B65B1, G01F11, G01F25, B65G65, B65B3