WO2005108207A2

WO2005108207A2 - Filling machine for filling sacks, as well as a method for adapting a filling machine

Info

Publication number: WO2005108207A2
Application number: PCT/NL2005/000349
Authority: WO
Inventors: Matheus Jozef Maria Coolen
Original assignee: Matheus Jozef Maria Coolen
Priority date: 2004-05-07
Filing date: 2005-05-09
Publication date: 2005-11-17
Also published as: NL1027168A1; WO2005108207A3; NL1027168C1

Abstract

A filling machine (1) is provided with a means of measuring (5) for determining the specific gravity of bulk material, for example, potting soil (3), as well as a means of weighing (19) for weighing a filled sack (17). The filling machine (1), furthermore, has a dosing device (7) for feeding potting soil and a conveyor belt (16) for removing fill5d sacks (17). The means of weighing (19) are made up of weighing elements (33) under the rollers (27) of the conveyor belt (16). In order to fill the sacks with the correct amount of potting soil, the filling machine (1) is provided with a means of control (21) for controlling the means of driving (23) the dosing device (7) during a set length of time. A control unit (35) is situated between the means of control (21) and the means of driving (23) the dosing device (7). If the measured specific gravity of the potting soil and the measured weight of the fill5d sacks indicate that the volume of the potting soil in the sacks is either too large or too small, then the control unit (35) will process the signal coming from the means of control (21) and send it to the means of driving (23).

Description

Filling machine for filling sacks, as well as a method for adapting a filling machine.

BACKGROUND OF THE INVENTION:

Field of the invention.

The invention relates to a filling machine, especially for filling sacks with a highly compressible material, in particular potting soil, comprising a dosing device for feeding bulk material into a receptacle which is to be filled, in particular a sack, a means of holding for holding onto a receptacle in a flow of bulk material falling from the dosing device, a means of removal for removing filled receptacles, a means of weighing for weighing a filled receptacle, and a means of control for controlling the means of driving the dosing device during a set length of time or until a set displacement of the dosing device has been reached for filling a receptacle or for holding a receptacle in the flow of bulk material falling from the dosing device during a set length of time. By a dosing device is meant any mechanism that can move or separate a determined amount of material from a larger amount. For this purpose, a dosing belt or a dosing screw may be considered. Some highly compressible bulk materials must be sold by volume according to guidelines. In accordance with these guidelines, due to the highly compressible nature of these bulk materials, this volume may not be determined by placing bulk material with a fixed cross-section on a dosing belt, which runs at a constant speed, and by setting the length of time in which this bulk material is poured into a receptacle. The volume must be determined by determining the specific gravity of the bulk material and the weight of a filled receptacle and to calculate the volume from that. If the volume is too large or too small then less or more bulk material must be put in the following receptacle.

Prior art.

Such a filling machine is generally known. In the known filling machine the means of weighing is an auxiliary conveyor belt situated on a weighing device that is set up in a conveyor belt which is interrupted for that purpose. The parts of the conveyor belt in front of and behind the auxiliary conveyor belt and the auxiliary conveyor belt itself must operate as exactly as possible at the same speed in order to transmit vibrations as little as possible to the weighing device. Depending on the weight measured, the determined specific gravity and the volume calculated from that information, the length of time during which the dosing device pours bulk material into a receptacle that is to be filled, can be adjusted manually or automatically. In order to adapt existing filling machines so that they meet these guidelines, a weighing device such as that described above must therefore be included in the conveyor belt. To do this, this conveyor belt has to be interrupted. This is a very labour-intensive adaptation.

Summary of the invention.

An objective of the invention is to provide a filling machine of the type described in the preamble in which sacks can be filled in accordance with the above- mentioned guidelines and which is simpler than the known filling machine. To this end, the filling machine according to the invention is characterized in that at least a part of the means of removal has been made so that it can weigh objects and is the means of weighing. The means of removal can be made in such a way that it can weigh objects, for example, by supporting a part of the means of removal by way of one or more weighing elements on the rest of the means of removal's construction. Because of this, the construction of the filling machine according to the invention is simpler than that of the known filling machine. In addition, existing filling machines can be more easily adapted to meet the above- mentioned guidelines. The conveyor belt preferably can be made so that it can weigh objects because there is a slide plate for weighing objects under a part of the conveyor belt, or because a number of the rollers under the conveyor have been set up in such a way that they can weigh objects. The means of removal preferably may comprise a conveyor belt that is made so that it can weigh objects because there is a slide plate for weighing objects under at least a part of the conveyor belt, in which the means of weighing objects comprises the slide plate or the means of removal can comprise a conveyor belt that moves over rollers or a roller conveyor that has been made so that it can weigh objects because at least a number of the rollers are made so that they can weigh objects, in which the means of weighing comprises these rollers. In order to automatically adjust the length of time during which the dosing device pours bulk material in a receptacle or the length of time during which a receptacle is held in a flow of bulk material falling from the dosing device, one must intervene in the filling machine's control system. As the control electronics of existing filling machines differ, for example, with regard to the pulse frequency, voltage, etc. one must adapt the design of the control electronics to each existing type of filling machine. An embodiment of the filling machine according to the invention, in which this is not necessary, is characterized in that there is a control unit situated between the means of control on the one hand and the means of driving the dosing device or the means of holding for holding onto the receptacles on the other hand, that is coupled to the means of weighing objects. Preferably the control unit has been made in such a way that it processes the signal coming from the means of control, and sends it to the means of driving or the means of holding onto objects, which signal is dependent on the values measured by the means of weighing objects and a set value of the specific gravity of the bulk material or a specific gravity of the bulk material determined by the means of measuring and passed on to the control unit. Because of this, all types of dosing can be adjusted, independently of whether they work with time dosing, pulses, analogue signals or other systems, without it being necessary to alter the control system of the filling machine. For each existing filling machine it is possible to realize an accommodation in a simple way; which reads in what the filling machine should do, calculates an adjustment and then sends this adjusted value to the filling machine. A further embodiment of the filling machine according to the invention is characterized in that the control unit has been executed in such a way that it stops the filling machine and/or ejects the filled sack should the measured weight of the sack deviate from the preset value more than a preset maximum percentage. In this way, filled sacks the weight of which is not within the upper and lower limits considered admissible are prevented from being delivered. The invention also relates to a method for adapting a filling machine of the type described in the preamble. As to the method, the invention is characterized in that at least a part of the means of removal is made so that it can weigh objects. An embodiment of the method according to the invention is characterized in that the means of removal comprises a conveyor belt and the means of weighing objects comprises a slide plate that is installed under the upper path of the conveyor belt. Another embodiment of the method according to the invention is characterized in that the means of removal comprises a conveyor belt that moves over rollers or a roller conveyor and the means of weighing comprises weighing elements that are placed between the bearings of at least a number of the rollers and the support situated underneath. A further embodiment of the method according to the invention is characterized in that the weight of the filled sacks is measured, then from the set or specific gravity of the bulk material the volume of the bulk material in the sack is calculated, after which depending on the size of the difference between the calculated volume and a target volume the control signal coming from the means of control is adjusted, and finally the adjusted signal is sent to the means of driving or the means of holding onto objects. Preferably, depending on the difference between the progressing average of the calculated volumes of the sacks and a target volume, the control signal coming from the means of control is adjusted. Furthermore, the control signal is only adjusted when the progressing average exceeds preset limit values.

Brief description of the drawings.

The invention will be elucidated more fully below by means of examples of embodiments of the filling machine according to the invention shown in the drawings. In these drawings: Figure 1 shows a schematic representation of a first embodiment of an adapted filling machine according to the invention; and Figure 2 shows a schematic representation of a second embodiment of an adapted filling machine. Detailed description of the drawings.

In figure 1 , a schematic drawing of a first embodiment of an adapted filling machine 1 according to the method is shown. The filling machine 1 is suitable for filling sacks with a highly compressible material, such as, for example, potting soil 3, and is provided with a means of measuring 5 for determining the specific gravity of bulk materials. This means of measuring 5 is shown here schematically by a rectangle and can be made as described in the Dutch patent no.1015076. Furthermore, the filling machine 1 has a dosing device 7 made as a dosing belt for feeding the potting soil 3 into the sack to be filled 9 and a means 11 for holding onto a sack in a flow of potting soil 3 falling from the dosing device 7. Furthermore, the filling machine 1 has a means of removal 15 for removing filled sacks 17, as well as means of weighing 19 for weighing a filled sack. The means of removal 15 is made up of a conveyor belt 16 moving over rollers 13 , 27. In order to fill the sacks with the correct amount of potting soil, the filling machine 1 is provided with a means of controlling 23 the dosing device 7, as well as a means of setting 25 for setting the length of time mentioned. For weighing filled sacks 17, a part of the conveyor belt 15 has been made so that it can weigh objects. This is attained because a number of the rollers 27 under the conveyor belt 15 have been set up so that they can weigh objects. To this end, generally known weighing elements 33 are placed between the bearings 29 of the rollers 27 and a support 31. There is a control unit 35 situated between the means of driving 23 the dosing device 7 and the means of control 21 which is coupled to the means of weighing 19 and the means of measuring 5. Should it turn out from the measured specific gravity of the potting soil in the bags and the measured weight of the filled sacks that the volume of the potting soil is too large or too small, then the control unit 35 will process the signal coming from the means of control 21 and send it on to the means of driving 23. In figure 2 a schematic representation of a second embodiment of an adapted filling machine 2 according to the invention is shown. All parts that are the same as those of the first embodiment are indicated by the same reference numbers. This filling machine 2 has a roller conveyor 18 instead of a conveyor belt. Here as well, a number 28 of the rollers 14, 28 have been set up so that they can weigh objects. The means of control 21 does not control here the means of driving 23, but the means of holding onto objects 11. With this embodiment, it is not the time during which the dosing device 7 runs that is regulated, but the time during which a sack 9 is held in the flow of falling potting soil. Although in the above the invention is explained on the basis of the drawings, it should be noted that the invention is in no way limited to the embodiments shown in the drawings. The invention also extends to all embodiments deviating from the embodiments shown in the drawings within the context defined by the claims. Thus, for example, it is also possible to make the conveyor belt so that objects can be weighed by placing a slide plate for weighing objects under a part of the conveyor belt, instead of setting up the rollers in such a way that they can weigh objects.

Claims

CLAIMS:

1. Filling machine (1), especially for filling sacks with a highly compressible bulk material (3) in particular potting soil, comprising a dosing device (7) for feeding bulk material into a receptacle which is to be filled, in particular a sack (9), a means of holding onto an object (11) for holding onto a receptacle in a flow of bulk material falling from the dosing device, a means of removal (15) for removing the filled receptacle (17), a means of weighing (19) for weighing a filled receptacle (17) and a means of control (21) for controlling the means of driving (23) the dosing device (7) during a set period of time or until a set displacement of the dosing device has been reached for filling a receptacle or for holding a receptacle (9) in the flow of bulk material (3) falling from the dosing device (7) during a set length of time, characterized in that at least a part of the means of removal (15) has been made so that it can weigh objects and is the means of weighing (19).

2. Filling machine according to claim 1, characterized in that the means of removal (15) comprises a conveyor belt (16) that has been made so that it can weigh objects because under at least a part of the conveyor belt there is a slide plate for weighing objects, in which the means of weighing comprises the slide plate.

3. Filling machine according to claim 1, characterized in that the means of removal (15) comprises a conveyor belt (16) that can move over rollers (13; 14) or a roller conveyor (18) that has been made so that it can weigh objects because at least a number of the rollers (27; 28) are set up so that they can weigh objects, in which the means of weighing ( 19) comprises these rollers (27; 28).

4. Filling machine according to one of the preceding claims characterized in that between the means of control (21) on the one hand and the means of driving (23) the dosing device (7) or the means of holding onto objects (11) for the receptacles (9) on the other hand, there is a control unit (35) that is coupled to the means of weighing (19).

5. Filling machine according to claim 4, characterized in that the control unit (35) has been made in such a way that it processes the signal coming from the means of control (21), and sends it to the means of driving (23) or the means of holding onto objects (11), which signal is dependent on the values measured by the means of weighing objects (19) and a set value of the specific gravity of the bulk material or a specific gravity of the bulk material (3) determined by the means of measuring (5) and passed on to the control unit.

6. Filling machine according to claim 4 or 5 characterized in that the control unit (35) has been made in such a way that it stops the filling machine (1) and/or ejects the filled sack (9) should the measured weight of the sack deviate from the desired preset value by more than a preset maximum percentage.

7. Method for adapting a filling machine comprising a dosing device (7) for feeding bulk material into a receptacle which is to be filled, in particular a sack (9), a means of holding (1 1) for holding onto a receptacle in a flow of bulk material falling from the dosing device, a means of removal (15) for removing filled receptacles (17), a means of weighing (19) for weighing a filled receptacle (17), and a means of control (21) for controlling the means of driving (23) the dosing device (7) for filling a receptacle during a set period of time or holding a receptacle (9) in the flow of bulk material (3) falling from the dosing device (7) during a set length of time, characterized in that at least a part of the means of removal (15) is made so that it can weigh objects.

8. Filling machine according to claim 7, characterized in that the means of removal comprises a conveyor belt and the means of weighing comprises a slide plate that is placed under the upper path of the conveyor belt.

9. Method according to claim 7 , characterized in that the means of removal (15) comprises a conveyor belt (16) that moves over rollers (13; 14) or a roller conveyor (18) and the means of weighing objects comprises weighing elements (33) that are placed between the bearings (29) of at least a number of the rollers (27; 28) and the support (31) situated underneath.

10. Method according to claim 7, 8 or 9 characterized in that the weight of the filled sacks is measured, then from the set or measured specific gravity of the bulk material, its volume in the sack is calculated, after which depending on the size of the difference between the calculated volume and a target volume the signal coming from the means of control is adjusted, and finally the adjusted signal is sent to the means of driving or the means of holding onto objects.

11. Method according to claim 10 characterized in that the control signal coming from the means of control is adjusted depending on the difference between the progressing average of the calculated volumes of the sacks and a target volume.

12. Method according to claim 11 characterized in that the control signal is only adjusted when the progressing average exceeds preset limit values.