MACHINE FOR BULK FILLING OF FLEXIBLE PLASTIC BAGS WITH LIQUID

Abstract: A machine for filling plastic bags with liquid, the bags being in the form of two flat sheets (1 and 2) sealed together around the periphery to form completely closed bags. The machine comprises a hollow punch (11) slidably mounted in sleeves (7 and 8) which are slidably mounted in face plates (5 and 6). The bag is first compressed between the face plates (5 and 6) and a hole punched into the bag by punch (11). Sheets (1 and 2) are then moved apart by a vacuum applied through annular recesses (16 and 17) in face plates (5 and 6). Liquid under pressure then enters the bag through ports (15) and the face plates (5 and 6) are then brought together, forcing the liquid into the rest of the bag. The sheets (1 and 2) are then sealed together around or adjacent the hole by circular heat sealers (18 and 19) or by straight line sealers (20 and 21). Punch (11) may be provided with means to evacuate the bag of air before filling.

Description: "MACHINE FOR BULK FILLING OF FLEXIBLE PLASTIC BAGS WITH LIQUID" THIS INVENTION relates to a machine for bulk filling flexible plastic bags with " liquid. The bags comprise two walls or webs of plastic material including laminated material welded or otherwise fastened together around the periphery to form a completely closed bag in an unfilled condition. At the present time flexible plastic bags are filled with liquids such as milk through a spout attached to the bag, the spout being sealed with a cap at the conclusion of the filling operation. This necessitates the use of expensive and elaborate filling mechanism whilst the cost of the spout and cap adds substantially to the cost of the bag whilst in many instances the contents of the bag are dis¬ pensed not through the spout as is intended but by simply cutting off one corner of the bag. . The present invention provides a machine for filling flexible bags, each consisting of two webs or walls of sealable material without exposing the interior of the bag to atmosphere prior to filling. In one form the invention provides a machine for filling of flexible plastic bags composed of two walls welded together around the periphery said machine comprising means for compressing portion of the two walls together, a punch for punching aligned holes in the two walls, means for separating the two walls in the vicinity of the holes to expose one or more ports or apertures in the punch through which liquid can be admitted to the interior of the bag, and means for sealing the walls together in the vicinity of the holes to close the bag after it has been filled with liquid. The invention will be better understood by reference to the following description of the specific embodiments shown in the accompanying drawings wherein:- Fig. 1 is a side elevation with the bag in the ini¬ tial position; Fig. 2 is a side elevation showing the punch in posi¬ tion after punching the holes in the bag; Fig. 3 is a side elevation showing the filling posi¬ tion; Fig. 4 is a side elevation showing the sealing posi¬ tion; Fig. 5 is a sectional view of a sleeve valve fitted into the hollow punch to be used when filling bags having a pre-fitted valve; Fig. 6 is a sectional view showing the sleeve valve in the filling position; Fig. 7 is a sectional elevation of one of the strip¬ ping sleeves; and Fig. 8 is an end view of the stripping sleeve of Fig. 7. The machine shown in the drawings is represented more or less diagrammatically with all extraneous components omitted. It consists essentially of two face plates 5 and 6 mounted one above the other so that they can be moved between a spaced apart position as shown in Fig. 1 and a clamping position as shown in Fig. 2. A rectangular bag consisting of two virgin walls 1 and 2 of plastic material welded together on all four sides is presented to the machine and located in the correct posi¬ tion by sensors 3 and 4 as seen in Fig. 1. It is prefer¬ able but not essential that the bag be presented to the sensors 3 and 4 so that one corner thereof is located between the face plates 5 and 6. The sensors actuate the -^ϋ 1 machine to bring the two face plates 5 and 6 together to clamp the bag therebetween. Stripping sleeves 7 and 8 which are slidably and rotatably mounted in the face plates are then brought together with a radial as well as an axial motion so that angled pins 9 (see Figs. 1 and 8) fitted to the ends of the sleeves penetrate at least partially into the respective adjacent bag walls as seen in Fig. 2. A hollow punch 11 moves axially through the sleeves to punch a hole in the bag the slugs 14 cut from both walls of material falling through the bottom sleeve as seen in Fig. 2. The punch seals against 0-rings 12 provided on the inner face of sleeve 7 and O-ring 13 provided on the inner face of sleeves. Annular recesses 16 and 17 surrounding the sleeves 7 and 8 are connected to a suction line {not shown) and the face plates 5 and 6 moved apart as shown in Fig. 3. The sleeves 7 and 8 move in unison with the respective face plates whilst the punch remains stationary. The material of the walls adjacent the hole are held by the pins 9 at the ends of the sleeves and the suction applied through annular recesses 16 and 7 -to move the walls apart. As the punch remains stationary the movement of the walls apart exposes ports 15 (see Fig. 3) to the space between the walls. Liquid under pressure is then fed through the hollow punch and ports 15 to the interior of the bag. When the required quantity of liquid has entered the bag the face plates 5 and 6 are brought together again forcing the product between them into the bag as shown in Fig. 4. The walls of the bag are heat sealed together either by mating circular heat sealers 18 and 19 immediately adja¬ cent the outer periphery of and surrounding the annular recesses 16 and 17. Alternatively by mating straight line sealers ' 20, 21 located near one edge of the face plates 5 and 6 facing the unrestricted portion of the bag may be used to make a seal. The portion of the bag in which the punched holes are located are external to the seal and may be cut away if so desired. Whilst the invention has been described with particular reference to the filling _of individual bags it will be appreciated that the bags may be formed in strip form and fed to the machine one after the other, each bag being removed from the strip after filling by tearing along a line of perforations located between adjacent bags in the strip. This may be achieved by the addition of a sleeve valve 22 (as shown in Figs. 5 and 6) with ports 23 and external groove 24 rotatably mounted with the hollow punch 11. On the initial withdrawal of the face plates 5 and 6 after the holes have been punched in the walls the bag can be evacuated by the connection of a vacuum source V to the punch 11 via groove 24 in the sleeve valve 23 which com¬ municates with ports 15 in the punch 11. After air has been evacuated the sleeve valve 23 is then partially rotated sealing off the vacuum source V to groove 24 and connecting the ports 23 in the valve to ports 15 in punch 11 permitting the liquid to fill the evacuated bag as described above. When the bag is fitted with pre fitted rigid valve or other dispensing device such as the dispensing valve used in bag-in-box type packaging it will naturally contain some air as a result of the valve filling operation and it is desirable to remove such air before filling the bag with the machine of the present invention.

Claims: THE CLAIMS defining the invention are as follows :- * 1. A machine for filling plastic bags composed of two walls welded together around the periphery comprising means for compressing portion of the two walls together, a punch for punching a hole in the compressed portion of the two walls, means for separating in the two walls in the vicinity of the punched holes to expose one or more ports or apertures in the punch through which liquid can be admitted to the interior of the bag and means for sealing the walls together in the vicinity of the holes to close the bag after it has been filled within liquid. 2. A machine as claimed in claim 1 wherein the means for compressing the two walls together comprise a pair of face plates which can be moved between a spaced apart position and a clamping position. 3. A machine as claimed in claim 2 wherein at least one of the face plates is provided with means for locating the bag in relation thereto. 4. A machine as claimed in claim 3 wherein the locating means acts as a sensor to initiate operation of the ma¬ chine. 5. A machine as claimed in claim 2, 3 or 4 wherein the separating means comprise a stripping sleeve in each face plate surrounding and slidably engaging the punch and capable of limited rotation about its axis, the inner end . of each of said stripping sleeves being provided with angled pins to penetrate at least partially into one of the walls of the bag. 6. A machine as claimed in claim 5 wherein each face plate is provided with an annular recess surrounding the /ϋRE sleeve mounted therein, each recess being connected to a suction line to assist in separating the two walls. 7. A machine as claimed in claim 5 or 6 wherein circular heat sealing means are mounted in mating positions in each plate surrounding outwardly of the stripping sleeve. 8. A machine as claimed in claim 5 or * 6 wherein straight line sealing means are mounted in mating positions in each plate so that when the bag is sealed the punch holes are located externally of the seal. 9. A machine as claimed in any one of the preceding claims wherein the punch is fitted with a sleeve valve rotatably mounted therein, said valve being provided with ports which can be rotated into or out of alignment with the ports or apertures in the punch and an external groove which can be rotated into and out of connection with a suction line connected to the punch. 10. A machine for filling plastic bags composed of two walls welded together around the periphery substantially as herein described and shown in Figs. 1 to 4, 7 and 8 of the accompanying drawings. 11. A machine as claimed in claim 10 wherein the punch is fitted with a sleeve valve as herein described and shown in Figs. 5 and 6 of the accompanying drawings.

Inventors: QUINSEE MICHAEL JOHN
Applicants: QUINSEE MICHAEL J, QUINSEE MICHAEL JOHN
Application year: 1982
Main classification: B65B3
IPC codes: B65B3, B65B31