US2852898A - Bag filling and sealing machines - Google Patents

Description

Sept. 23, 1558 c. BERG BAG FILLING AND SEALING MACHINES 2 Sheets-Sheet 1 Filed March 5. 1958 INVENTOR. CARL BERG uJM HIIIE EO AT TORNEYS Sept. 23, 1958 C. BERG BAG FILLING AND SEALING MACHINES 2 Sheets-Sheet 2 Filed March 5, 1958 FIG. 8

INVENTORQ CARL Bans I. I Y I ATTORNEYS United States Patent fifice 2,852,898 Patented Sept. 23, 1958 BAG FILLING AND SEALING MACHINES Carl Berg, Minneapolis, Minn., assignorto Super Valu Stores, Inc., Hopkins, Minn., a corporation of Delaware Application March 1958, Serial No. 719,359 3 Claims. (Cl. 53-182) My invention relates generally to bag filling and clo sure forming machines and more particularly to machines for forming, filling and sealingbags formed from thermoplastic sheet material.

Machines of the class immediately above described comprise cooperating heads movable toward and away from each other in a horizontal plane and intersecting the path of travel of a tubular thermoplastic bag-forming member. One of said heads is provided with vertically spaced horizontally extended heater elements for simultaneously sealing the top of a filled bag and the bottom of the next succeeding bag when the heads are brought into sealing engagement. Furthermore, one of the heads is provided with a cutter blade for transversely severing the tubular member intermediate the heating elements during the sealing operation. In this manner, the filled sealed bags are successively separated from the tubular member during each reciprocation of the heads. In practice, I have found that only too frequently the thermoplastic material sticks to the heating element during the top sealing operation on the filled bag. As a result, the filled bag is not discharged or released from the heads during the cycle of reciprocal movements thereof and the machine becomes jammed with a consequent loss of product and time.

The primary object of my invention is the provision of novel means for positively separating filled bags from the heating elements responsive to movements of said heads away from each other whereby to avoid jamming of the machine and to bring about uninterrupted operation thereof.

A further object of my invention is the provision of a device of the class immediately above described which incorporates a minimum of working parts and hence is inexpensive to produce and to maintain.

A still further object of my invention is the provision of a device of the class above described which is positive in its action and rugged and durable in construction.

The above and still further objects of my invention will become apparent from the following detailed speci fication, appended claims and attached drawings.

Referring to the drawings wherein like characters indicate like parts throughout the several views:

Fig. 1 is a fragmentary view in side elevation of a conventional bag forming, filling and sealing machine illustrating my novel invention attached thereto, some parts being broken away and some parts shown in section;

Fig. 2 is a fragmentary View in side elevation of some of the structure of Fig. 1 showing a different position of some of the parts and some additional parts being added;

Fig. 3 is a view in front elevation of one of the bag sealing heads of the machine of my invention; and

Fig. 4 is a fragmentary view corresponding to a portion of Fig. 1 but showing a difierent position of some of the parts.

Referring with greater particularity to the drawings, the numeral 1 indicates in its entirety a machine of the conventional type for the forming, filling and sealing of bags from thermoplastic sheet material. The machine 1 includes an upright supporting member 2 to which is attached, by means not shown, a vertically disposed depending former and filler tube 3 formed from suitable metal or the like and as shown having a circular crosssection. Fed onto the forming and filling tube 3, from a source not shown such as a spool, is an elongated strip 4 of thermoplastic material, such as cellophane or polyethylene. As shown particularly in Fig. 2, the strip 4 is caused to be wrapped about the tube 3 longitudinally thereof by passing same between the tube 3 and a circumferentially spaced concentric sleeve 5. Thereafter, the overlapped edges 6 of thestrip 4 are sealed by suitable heating means 7 comprising heated rollers or the like 8, whereby to form a continuous bag forming tube 9.

Below the combination forming, filling tube 3 and intersecting the path of travel of the tubular bag forming member 9 in its downward course, are a pair of cooperating heads 10 and 11 which are suitably mounted for movements toward and away from each other in a horizontal plane by mechanism, not shown. As shown, the head 10 has a pair of vertically spaced horizontally extended heating elements 12 and 13 of conventional design which forcefully engage opposed shoulders 14 and 15 respectively carried by the head 11, the members 12, 14 cooperating to seal the top of a filled bag 16 and the members 13 and 15 cooperating to simultaneously seal the bottom of the next succeeding bag 17, when the heads 14), 11 are moved into engagement with each other, as shown in Fig. 1.

A horizontally extended cutter blade 18, shown as being carried by the head 11, is positioned between the heating elements 12, 13 and severs the tubular member 9 to separate the filled bag 16 from the immediately succeeding bag 17.

In order to positively assure separation of the filled bags 16 from the heating element 12 during movements of the heads 10, 11 away from each other, so as to assure uninterrupted operation of the machine 1, I provide a pad 19 which is carried by the head 10 in downwardly spaced relation to the heating element 12 and which engages the side of the filled bag 16 adjacent the upper end portion thereof, as shown in Fig. 1. During sealing movements of the elements 12, 14, the pad 19 cooperates with a similar pad 20 carried by the head 11 and engageable with the opposite side of the bag 16 adjacent its upper end portion, all in a conventional manner. However, the pad 19 is secured to the head 10 through the medium of an arm 21 connected thereto, as at 22, and a horizontally disposed rock shaft 23 that is journaled in bearing brackets 24 secured to the head 10 as indicated at 25 in Fig. 4. Rigidly secured to the rock shaft 23 is a crank arm 26 to the outer end of which is pivotally secured, as at 27, the outer end of an armature 28 of a solenoid 29 secured to the head 10. The solenoid 29 is interposed in an electrical circuit 30 including a control switch 31, the operating button 32 of which is positioned to be engaged by the head 10 upon relative movement thereof away from the head 11 whereby the solenoid 29 is energized, as indicated in Fig. 4. As there shown, when the top portion of a filled bag 16 becomes adhered to the heating element 12 or other adjacent portions of the head 10, energization of the solenoid 29 by closing of the switch 31 causes the pad 19 to swing laterally and downwardly into the path of travel of the tubular member 9 and filled bag 16, thereby forcefully removing the filled bag 16 from the head 10, as indicated by dotted lines, whereby it drops vertically downwardly into a guide trough 33 or the like and hence onto a conventional conveyor belt or the like 34.

My invention has been thoroughly tested and found to be completely satisfactory for the accomplishment of the above objects and while I have shown a preferred embodiment thereof, I wish it to be specifically understood that same is capable of modification without departure from the scope and spirit of the appended claims.

. What I claim is: I

1. An attachment for machines for forming, filling and sealing bags formed from thermoplastic sheet material in tubular form, said machines including cooperating heads movable toward and away from each other in a horizontal plane and intersecting the path of travel of a tubular bag-forming member, sealing means on said heads, said means including a pair of vertically. spaced horizontally extended heating elements on one of said heads for simultaneously sealing the top of a filled bag and the bottom of the next succeeding bag, a cutter blade carried by one of said heads and positioned to transversely sever said tubular member intermediate said heating elements when said heads are brought into sealing engagement, said attachment comprising a pad engageable with one side of a filled bag adjacent its upper end portion when said heads are in sealing engagement, means mounting said pad for swinging movements laterally and downwardly into said path of travel, and means for imparting said swinging movements to said pad responsive to movements of said heads away from each other whereby to positively separate said bag from said No references cited.

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