GB1570410A

GB1570410A - Material dispensing device comprising apparatus for controlling the quantity of a dispensed material

Info

Publication number: GB1570410A
Application number: GB1532977A
Authority: GB
Original assignee: Carle and Montanari SpA
Current assignee: Carle and Montanari SpA
Priority date: 1976-04-14
Filing date: 1977-04-13
Publication date: 1980-07-02
Also published as: DE2715944A1; JPS5732328B2; FR2348478A1; DE2715944C2; FR2348478B1; DD129736A1; JPS53128364A; CH613845A5; NL7704018A; DK162477A

Abstract

The device (1) comprises two pistons (6, 7) which cooperate with a casting head (8). These pistons perform a to-and-fro movement and are operated by a rod (18) via levers (12, 13) and arms (2, 3). The alternating movement of the rod (18) is generated by an eccentric disc (19). The rod (18) has a stop means (22) which rests during each alternating movement against the end of a threaded rod (23) displaceable axially by a stepper motor (27). This motor is actuated, via leads (28), by electronic scales (30) which compares the current weight of each mould (10) filled with a predetermined value and which transmits a signal to the motor (27) which, by means of a displacement of the threaded rod (23), adjusts the travel of the pistons (6, 7) and hence the quantity injected into the moulds (10). In this way the weight of the product cast in the moulds is adjusted continuously and with great precision. <IMAGE>

Description

(54) MATERIAL DISPENSING DEVICE COMPRISING APPARATUS FOR CONTROLLING THE QUANTITY OF A DISPENSED MATERIAL (71) We, CARLE & MONErANARI S.p.A., of Via Neera 39, Milan, Italy, an Italian body corporate, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The present invention relates to a material dispensing device comprising apparatus for controlling the quantities of a material dispensed to receptacles. The invention is particularly, but not exclusively, concerned with the filling of moulds with chocolate or the like.

For the making of confectionery items, dispensing or filling machines are used as appears from German Patent 972 397, which pour the material into suitable recesses in moulds which are moved on a conveyor belt below the pouring head of the machine.

Confectionery items, for example chocolate bars, are required by law to clearly indicate on the wrapping the composition of the product and its weight which must never be lower than that indicated. For this reason, filling machines of this kind are arranged always to pour into the moulds slightly greater amounts of the material than are required to produce the nominal weight, so that the final weight will exceed by some grams the weight indicated on the wrapping.

The filling machines are therefore provided with regulating means which are operated manually by the machine operator who, from time to time, stops the whole installation to remove one of the filled moulds for checking its weight, after which he reinserts the mould and, after regulating the quantity poured as required, restarts the machine. This is done to ensure the pouring of a higher or lower quantity of the product into each mould and to make sure that the final weight of each item will be slightly in excess of that indicated on the wrapping.This manual control not only requires labour and interruptions of the manufacturing process, but, because the checks are made intermittently, the excess weight poured into the moulds to avoid dropping below the weight value given on the finished product cannot be maintained within appropriately narrow limits and the tolerances used are rather large.

If it is considered that the overweight amount may be about 10 to 20 grams for each mould and that about 30 moulds may be filled a minute, it will be seen that there can be a considerable difference by the end of a working day between the amount of the product actually poured and the nominal weight of the items produced.

The invention accordingly provides a material dispensing device comprising apparatus for controlling quantities of a material dispensed to receptacles, the apparatus comprising respective means for measuring the weight of each receptacle before the material is dispensed thereto; means for measuring the weight of each receptacle after material has been dispensed thereto, and comaprator means arranged to subtract the rectpacle weight from the weight of the receptacle and the material dispensed thereto and to compare the measured difference with a predetermined weight to provide an output which is supplied to the material dispensing means for increasing or decreasing the quantity of materials dispensed to each receptacle.In this way, the amount of material dispensed is adjusted so as to minimize any difference between the measured and the predetermined weight, a continuous high-precision control and regulation of the material dispensed to the receptacles being obtained. Alternatively, said comparator means is arranged to provide the output only when the weight difference exceeds a predetermined amount or falls outside predetermined limits.

The dispensing device of the invention allows continuous and automatic control and regulation of the weight of material poured into or otherwise supplied to receptacles or moulds, without the need to interrupt the pouring and conveying operations and without the need of labour. In addition, the tolerances required to reach the required overweight and to avoid drop to below the nominal weight are much narrower, with a considerable saving in the material used, be it chocolate, cream or some other material.

The moulds nowadays normally used for confectionery are made of synthetic materials and can have substantial differences in weight. This influences the final result in a negative way while, as already mentioned, it is essential that the amount of the material poured remains within certain limits to ensure that the final product has always a given weight.

According to the invention, means are provided for measuring not only the weight of each receptacle and the material dispensed thereto, but also the weight of each empty receptacle. Upstream of the filling or dispensing machine, another weighing apparatus being arranged to transmit the apparatus is thus provided for weigh ing each single mould, this weighing weight of each empty mould to the firstmentioned weighing apparatus for comparison with the weight of the filled moulds.

A comparison device in the first weighing apparatus processes the data obtained from the other weighing apparatus by means of a differential arrangement and generates impulses for adjustment of the filling machine.

The present invention will be readily understood from the following illustrative description which is given by way of example and with reference to the accompanying drawings, in which: Fig. 1 is a schematic side view of a chocolate dispensing device incorporating a quantity control apparatus and Fig. 2 is a similar view of a modified form of the apparatus for use with the dispensing device of Fig. 1.

As shown in Fig. 1, a dispensing device has at an upper part thereof two arms 2 and 3 arranged to oscillate around respective axes 4 and 5. The lower ends of the oscillating arms 2, 3 are pivotably connected to a series of pistons 6 and 7 which co-operate with a pouring or dispensing head 8, schematically indicated by the area within a broken line. Moulds 10 are conveyed by a conveyor belt 9 below the head 8. In synchronism with the movement of the moulds 10, the arms 2,3 control in and out movements of the piston 6,7 whereby the product supplied by the head 8 is injected though ducts (not shown) into the recesses 11 of the moulds 10.

To allow the arms 2,3 and consequently the pistons 6,7 to perform these oscillating movements, the arms are connected to respective levers 12,13 which also oscillate around the axes 4,5. The free ends of the levers 12,13 are formed as sectors provided with gear teeth which mesh with respective racks 16,17 carried at the upper end of a rod 18 arranged for reciprocating movement in the direction of the arrow f. The reciprocating movement of the rod 18 and thus of the levers 12,13, the arms 2,3 and the pistons 6,7 is generated by a cam disk 19, the rod 18 carrying a cam follower roller 20 in contact with the periphery of the cam disk 20. The levers 12,13 are controlled by springs 21a, 21b which urge the levers 12,13 to the lowered position.The rod 18 also carries a projecting stop 22 which can engage the upper end of a screw threaded rod 23 received in a tapped hole in a bracket 24 fixed to the frame 25' of the machine 1.

The threaded rod 23 is engaged with a bevel gear 25 which meshes with another bevel gear 26 driven by a motor 27, preferably a stepping motor.

Rotation of the bevel gears 25,26 causes the screw threaded rod 23 to be raised or lowered. The stop 22 engages the rod 23 when moving downwardly under the action of the springs 21a, 21b, so the rod 23 defines a lower limit to the downward movement of the rod 18. Thus the stroke of the rod 18 and therefore also the suction stroke of the pistons 6,7 of the filling machine will depend on the position of the, rod 23.

Thus adjustment of the position of the rod 23 allows the quantity of product supplied to the moulds 10 to be easily regulated.

The stepping motor 27 is connected by conductors 28 with a comparison and control device 29 of a weighing apparatus 30 including a weighing table 32 over which the moulds 10 are passed after filling. The weighing apparatus 30 contains electronic circuitry and provides a signal to the stepping motor 27 over the conductors 28 for adjusting the stroke of operation of the dispensing pistons 6,7 if the weight of the product which is obtained by comparing the weight of the empty mould with that of the filled mould, as described below, during the weighing step on the weighing table 32 differs from a predetermined weight established by means of a presettable programming circuit 31.

As shown in Fig. 2, upstream of the filling device 1, which is indicated only schem atically by means of the chain-dotted centre line, another weighing apparatus 40 is provided for weighing on its weighing table 41 moulds 10 the recesses 11 of which have not yet been filled with the product. The weighing apparatus 40 makes it possible to compensate for and to keep account of any possible weight variations between the empty moulds 10. In the weighing apparatus 40, means 42 is provided for registering the weight signals obtained and conductors 43 transmit these empty mould weight signals to the control device 29 of the weighing apparatus 30 so that this can provide a signal for adjusting the amount of material to be poured into the mould which is also a function of the empty mould weight.

For this purpose the control device 29 of the weighing apparatus 30 is provided with an electronic differential device designed to substract the weight of the empty mould from that of the filled mould. If the differential weight, that is, the weight of the product contained in the mould, corresponds to the predetermined value, no ad jusament takes place; if the differential weight differs therefrom, the stepping motor will regulate the dispensing piston stroke in the dispensing machine 1 accordingly.

The operation of the equipment shown in Fig. 1 is now described. The weight of each mould 10 when filled is ascertained by means of the weighing table 32 of the weighing apparatus 30 positioned immediately downstream of the dispensing machine 1. The differential weight is compared by means of the comparing and control device 29 with the predetermined weight and registered by the apparatus. If the differential weight differs from the predetermined weight, the device 29 transmits over the conductors 28 a signal to the stepping motor 27 and the strength of the signal or its duration effects operation of the motor so as to rotate the bevel gears 25,26, to reduce the stroke of the pistons 6,7 and so also to reduce the amount of the product poured into the moulds.If on the other hand the differential weight is found to have dropped by a certain quantity below the predetermined weight, the signals emitted by the device 29 and transmitted by the conductors 28 will act in the opposite sense, to cause the stepping motor to increasing the stroke of the pistons 6,7 and thus to increase the amount of product fed into the moulds 10.

Although the present illustrative description relates to a dispensing machine with a piston-controlled delivery system, it will be evident that the control apparatus of the invention can be applied instead to filling machines of different construction, it being sufficient to adapt the adjusting means to the actual pouring arrangements.

With the equipment shown in Fig. 2, the empty mould 10 is weighed on a weighing table 41 and a signal representing the value obtained is transmitted by the registration means 42 over the conductors 43 to the comparing and regulating device 29 so that this will allow for the weight of the empty mould before comparing the measured values with the predetermined ones.

WHAT WE CLAIM IS: 1. A material dispensing device comprising apparatus for controlling quantities of a material dispensed to receptacles, the apparatus comprising respective means for measuring the weight of each receptacle before the material is dispensed thereto; means for measuring the weight of each receptacle after material has been dispensed thereto; and comparator means arranged to subtract the receptacle weight from the weight of the receptacle and the material dispensed thereto and to compare the measured difference with a predetermined weight to provide an output which is supplied to the material dispensing means for increasing or decreasing the quantity of materials dispensed to each receptacle.

2. A device as claimed in claim 1, in which said comparator means is arranged to provide the output only when the weight difference exceeds a predetermined amount or falls outside predetermined limits.

3. A device as claimed in claim 1 or 2, in which the predetermined weight is selectively adjustable.

4. A device as claimed in claim 1, 2 or 3, in which each weight measuring means is arranged to electrically register the weight measured thereby.

5. A device as claimed in any preceding claim, further comprising dispensing pistons whose strokes are adjustable to adjust the quantity of material dispensed thereby to each receptacle.

6. A device as claimed in claim 7, in which each piston stroke is adjustable by adjustment of the position of a stop limiting movement of an abutment moving with the pistons.

7. A device as claimed in claim 8 in which the stop comprises an end of a screw

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. atically by means of the chain-dotted centre line, another weighing apparatus 40 is provided for weighing on its weighing table 41 moulds 10 the recesses 11 of which have not yet been filled with the product. The weighing apparatus 40 makes it possible to compensate for and to keep account of any possible weight variations between the empty moulds 10. In the weighing apparatus 40, means 42 is provided for registering the weight signals obtained and conductors 43 transmit these empty mould weight signals to the control device 29 of the weighing apparatus 30 so that this can provide a signal for adjusting the amount of material to be poured into the mould which is also a function of the empty mould weight. For this purpose the control device 29 of the weighing apparatus 30 is provided with an electronic differential device designed to substract the weight of the empty mould from that of the filled mould. If the differential weight, that is, the weight of the product contained in the mould, corresponds to the predetermined value, no ad jusament takes place; if the differential weight differs therefrom, the stepping motor will regulate the dispensing piston stroke in the dispensing machine 1 accordingly. The operation of the equipment shown in Fig. 1 is now described. The weight of each mould 10 when filled is ascertained by means of the weighing table 32 of the weighing apparatus 30 positioned immediately downstream of the dispensing machine 1. The differential weight is compared by means of the comparing and control device 29 with the predetermined weight and registered by the apparatus. If the differential weight differs from the predetermined weight, the device 29 transmits over the conductors 28 a signal to the stepping motor 27 and the strength of the signal or its duration effects operation of the motor so as to rotate the bevel gears 25,26, to reduce the stroke of the pistons 6,7 and so also to reduce the amount of the product poured into the moulds.If on the other hand the differential weight is found to have dropped by a certain quantity below the predetermined weight, the signals emitted by the device 29 and transmitted by the conductors 28 will act in the opposite sense, to cause the stepping motor to increasing the stroke of the pistons 6,7 and thus to increase the amount of product fed into the moulds 10. Although the present illustrative description relates to a dispensing machine with a piston-controlled delivery system, it will be evident that the control apparatus of the invention can be applied instead to filling machines of different construction, it being sufficient to adapt the adjusting means to the actual pouring arrangements. With the equipment shown in Fig. 2, the empty mould 10 is weighed on a weighing table 41 and a signal representing the value obtained is transmitted by the registration means 42 over the conductors 43 to the comparing and regulating device 29 so that this will allow for the weight of the empty mould before comparing the measured values with the predetermined ones. WHAT WE CLAIM IS:

1. A material dispensing device comprising apparatus for controlling quantities of a material dispensed to receptacles, the apparatus comprising respective means for measuring the weight of each receptacle before the material is dispensed thereto; means for measuring the weight of each receptacle after material has been dispensed thereto; and comparator means arranged to subtract the receptacle weight from the weight of the receptacle and the material dispensed thereto and to compare the measured difference with a predetermined weight to provide an output which is supplied to the material dispensing means for increasing or decreasing the quantity of materials dispensed to each receptacle.

7. A device as claimed in claim 8 in which the stop comprises an end of a screw

threaded rod received in a tapped hole in a fixed bracket, the rod being rotatable to effect the adjustment.

8. A device as claimed in claim 9 comprising a stepping motor arranged to rotate the rod through a gear connection.

9. Apparatus, as defined in any of claims 1 to 4, for controlling quantities of material dispensed to receptacles in an adjustable dispensing device.

10. A chocolate dispensing device substantially as hereinbefore described with reference to the accompanying drawings.