GB2072143A - Machine for filling packages - Google Patents

Abstract

A volume-filling machine for filling packages or containers (18) with a volume of a material, for example peat, comprises a source of supply of the material (1), a capacity- measuring receptacle (A), means (7, 8) for detecting and controlling the filling of the capacity-measuring receptacle, means for transferring the material received by the capacity- measuring receptacle to an open- topped receiving package or container, and means (12) for positioning and supporting the receiving package or container below the receptacle during the filling operation. The detecting means causes shutting-off of the receptacle from the supply when the receptacle has received the volume of material. <IMAGE>

Description

SPECIFICATION Machine for filling packages The invention relates to a machine for filling packages or containers, for example, bags or sacks, with a loose, solid material.

The machine of the present invention is of the volume-filler type; that is, the quantity of material to be added to the package or container is not measured by weight but by volume or capacity. By volume-filling, materials which are difficult to weigh due to varying composition may be packaged in acceptable standard measures. An example of such a material, which is suitable for use in the present invention, is peat. Peat and peat-based composts for use in horticulture when in milled form are always difficult materials to handle and present problems in packaging, due to the varying water content and physical nature of the peat. Peat and peat-based composts, for example, may be packaged by the machine of the present invention into suitably sized packs for the retail garden trade with a capacity measure in the range, for example, of 3 to 10 litres.Other materials which may be packaged by the machine of the present invention inciude, for example, forest bark, sand, sawdust, perlite and vermiculite.

The packages or containers may be made of plastics material, for example, polythene, sacking, paper including kraft paper. Polythene bags or sacks are particularly suitable for use in the present invention.

Machines of the volume-filler type are commercially available, but the present invention is based on the problem of handling materials with, for example, a water content which renders them liable to stick to, or block parts of, the machine and thus reduce its efficiency.

This problem is solved by a combination of parts which make up the machine as hereinafter described, thus allowing for a rapid through-put of material and, hence, a high filling rate.

According to the invention there is provided a machine for filling packages or containers which comprises in combination a volume- or capacitymeasuring receptacle for receiving a material to be packaged from a source of supply thereof, the wall(s) and the base of the receptacle being adapted for movement relative to one another in a substantially horizontal direction in such a manner that the bottom of the receptacle may be closed, and maintained closed, while the receptacle is receiving the material and may thereafter be opened, and maintained open, means for effecting the said relative movement so that the bottom of the receptacle is closed, whereby the material received by the receptacle from the source of supply is retained in the receptacle, means for sensing and monitoring the filling of the receptacle with the material and for shutting the receptacle off from the source of supply when it has received the material, means for positioning and supporting an open-topped receiving package or container below the receptacle, means for effecting the said relative movement so that the bottom of the receptacle is opened, whereby the material in the receptacle may fall therefrom into the receiving package or container.

A practical example of the invention is described in detail below with reference to the drawings which illustrate only one specific embodiment, in which: Figure I is a view, partly in section and partly schematic, of a machine constructed in accordance with the invention, Figure II is a side elevation view of clamps for holding the package or container during filling, and Figures lli(A) and III(B) are plan views of the clamps.

Turning now to the specific embodiment of the invention illustrated in the drawings, there is shown in Figure I a paddle stirrer (2) to assist the flow of material to be packaged from a hopper (1).

The paddle stirrer is driven by a 0.75 KW electric motor (3) through a low ratio gearbox (4) to give a rotation of 12 r.p.m. A transfer shaft (5) has helical arrangement of pins on the shaft to assist further mixing and shredding of material and the filling of a receptacle volume box A. The transfer shaft (5) is driven by a 0.75 KW electric motor (6) at a rotation of 100 r.p.m. The filling of volume box A is controlled by a photocell unit comprising sender and receiver "eyes" (7) and (8). The effective range of the photocell unit used is of up to 1,200 mm. The photocell unit and the electric motors for driving the paddle shaft (2) and the transfer shaft (5) are linked by wiring to a relay box (9) which has a slave relay unit with a current carrying capacity of approximately 10 amps. Metal plate (10) acts as a shut-off slide and is attached to volume box A and is movable therewith.The metal plate (10) prevents the fall of the material to be packaged when volume box A moves from a' to b'. Volume box A is moved from position a' to position b' by means of compressed air ram (1 1).

Package clamp (12) is activated by compressed air ram (13). The compressed air rams (11) and (13) are operated by an electrically-operated air solenoid valve (14). Compressed air may be obtained from mains air which passes through a reducing valve (not shown) to give a pressure of 40 p.s.i.g. before entering the solenoid valve. The compressed air passes from the solenoid valve to rams (11) and (13) through suitable tubing.

Control of the filling operation is by means of an operators foot pedal (15) which is linked by wiring to the solenoid valve. The solenoid valve (14) is connected by wiring to the relay box (9). Volume box A and shut-off slide (10) are constructed of suitable stainless steels to prevent corrosion.

Figures II and Ill illustrate the packing clamp.

The clamp comprises a fixed section (16) and a movable section (17) operated by the compressed air ram (13). When the foot pedal (15) is depressed section (17) of the clamp expands by the pulling action of ram (13) in the direction shown to hold the package tightly around the external surface of sections (16) and (1 7) of the clamp thereby allowing free discharge of material from box A at position b' into the package. When the foot pedal (15) is released section (17) of the clamp returns to the position shown in III(A) and the filled package falls from the clamp.The package-filling operation may be wholly or partially operatorcontrolled, or a partially or wholly automatic system may be used in conjunction with the machine described herein in such a manner that any two or more of the steps required for filling the packages or containers are carried out in a desired sequence by appropriate electrical interconnection of the means for carrying out such steps. The volume or capacity measure of volume box A may be changed to provide for the filling of differing package sizes. A filling rate of up to 15 packages per minute may be achieved with small packages in the aforementioned size range of 3 to 10 litres.

In operation, the hopper (1) is filled with the material to be packaged and paddle (2) and transfer shaft (5) are operated to move material into volume box A by operating the foot pedal.

When volume box A is filled to the level of the photocell unit, the light beam is interrupted and paddle (2) and transfer shaft (5) stop. Foot pedal (15) is again operated and the electric solenoid (14) activates ram (11) which moves volume box A from position a' to position b' and at the same time the clamp expands by the action of ram (13) to hold the package in position around the external surface of the clamp (12). When volume box A is at position b' the material in the box A drops into the package (18). The release of the foot pedal (15) causes compressed air rams 1) and (13) to retract so that the package is released and volume box A returns to position a'. Upon the return of volume box A to position a', some material trapped above slide (10) falls into the empty volume box A thereby clearing the light beam pathway between the photocell unit (7) and (8).

This in turn activates paddle (2) and transfer shaft (5) thus re-starting the filling operation. The operator then places the next package onto clamp (12) and depresses pedal (15). The filled packages are removed from under the clamp and conveyed to another position for sealing.

Claims (12)

1. A machine for filling packages or containers which comprises in combination a volume or capacity-measuring receptacle for receiving a material to be packaged from a source of supply thereof, the wall(s) and the base of the receptacle being adapted for movement relative to one another in a substantially horizontal direction in such a manner that the bottom of the receptacle may be closed, and maintained ciosed, while the receptacle is receiving the material and may thereafter be opened, and maintained open, means for effecting the said relative movement so that the bottom of the receptacle is closed, whereby the material received by the receptacle from the source of supply is retained in the receptacle, means for sensing and monitoring the filling of the receptacle with the material and for shutting the receptacle off from the source of supply when it has received the material, means for positioning and supporting an open-topped receiving package or container below the receptacle, means for effecting the said relative movement so that the bottom of the receptacle is opened, whereby the material in the receptacle may fall therefrom into the receiving package or container.

2. A machine as claimed in claim 1, wherein said means for shutting off the receptacle from the source of supply comprises a movable barrier adapted to be moved to a position below the source of supply such that the latter is shut off from the receptacle responsive to said means for moving the receptacle to the discharge position.

3. A machine as claimed in claim 1 or claim 2, wherein said means for sensing and monitoring the filling of the receptacle comprises photoelectric means adapted to detect when the receptacle has received the required volume of the material.

4. A machine as claimed in any one of the preceding claims, wherein said means for effecting the said relative movement comprises a receptacle-moving ram adapted to move the receptacle horizontally with respect to its base.

5. A machine as claimed in claim 4, wherein the said receptacle-moving ram is adapted to be operated by compressed air.

6. A machine as claimed in any one of the preceding claims, wherein the said means for positioning any open-topped receiving package or container below the receptacle comprises an expandable package clamp adapted to fit within the top of the package or container, to be expanded there, so as to support and maintain the top of the package open during filling, and thereafter to be contracted so as to enable the filled package to be removed therefrom.

7. A machine as claimed in claim 6, wherein the said package clamp is adapted to be operated by a clamp-operating ram.

8. A machine as claimed in claim 7, wherein the said clamp-operating ram is adapted to be operated by compressed air.

9. A machine as claimed in any of claims 4 to 8, wherein the said rams are adapted to be operated by an electrically operated air solenoid valve.

10. A machine as claimed in any one of the preceding claims including means for starting and stopping filling.

1 A machine as claimed in claim 10, wherein the said starting and stopping means comprises a foot-pedal or the like.

12. A machine as claimed in claim 10 or claim 11 , wherein at least two of the said means for starting and stopping, shutting off the source of supply, sensing and monitoring the filling of the receptacle, effecting relative movement of the wall(s) and base of the receptacle, and for positioning and supporting the open-topped receiving package or container are electrically interconnected in such a manner that the functions ofthe said means are caused to occur in a desired sequence.

1 3. A machine for filling packages or containers, substantially as hereinbefore described with reference to the accompanying drawings.