US3112679A

US3112679A - Device for applying binding strips to bags of rectangular cross section

Info

Publication number: US3112679A
Application number: US82861A
Authority: US
Inventors: Jungmayr Theodor
Original assignee: FR Hesser Maschinenfabrik AG
Current assignee: FR Hesser Maschinenfabrik AG
Priority date: 1960-01-27
Filing date: 1961-01-16
Publication date: 1963-12-03
Anticipated expiration: 1980-12-03

Description

Dec. 3, 1963 1-. JUNGMAYR 3,112,679

DEVICE FOR APPLYING BINDING STRIPS TO BAGS OF RECTANGULAR CROSS SECTION Filed Jan. 16, 1961 2 Sheets-Sheet 1 Fig. 1

Dec. 3, 1963 I T. JUNGMAYR 3,112,679

DEVICE FOR APPLYING BINDING STRIPS TO BAGS 0F RECTANGULAR CROSS SECTION 2 Sheets-Sheet 2 Filed Jan. 16, 1961 Fig. 3

Fig. 4

United States Patent F 3,112,679 DEVICE FER APPLYWG EENDZNG STREPS T0 BAGS OF RECTANGULAR CRGSS SEQTKGN Theodor .lungmayr, Stuttgart-Nerd, Germany, assignor to Firma Fr. Hesser, Maschiuenfahrik-Ahtiengesellsshaft, Stuttgart-Bad Cannstatt, Germany, a corporation of Germany Filed Kan. 16, 1%1, Ser. No. 32,863 Claims priority, application Germany Jan. 27, 196i) 8 Claims. (Cl. 93-45) This application reiates to apparatus and methods for forming slots in a bag through which a fastening strip may be introduced to permit forming a closure for the bag.

In the case of bags having a folded over closure at the mouth of the bag and a fastening or binding strip to keep it folded over, it is known to pass the strip through the narrower sides of the bag in the immediate vicinity of the front or rear wall of the latter.

It is an object of this invention to present a device which, in a very simple fashion, permits the completely automatic application of binding strips in this way to the bag mouth.

A further object is to enable such application to take place without detracting from the rate of operation of the machine with which it is used. Such a machine is advantageously an automatic packaging machine.

For this purpose the device according to this invention is characterised, in accordance with a primary feature, by two pairs of cutting tools in scissors arrangement which are adapted to be introduced into the mouth of a packaging bag of rectangular cross section, the principle being that each tool pair, in operation, is adapted to engage one of the mutually opposed sides of the bag and to form a slot or slit in this side; further, each pair of cutting tools is intended at the same time to form guide means for a binding strip which is to be pushed through the slit. The guide means can be augmented by a plate which extends between the two pairs of cutting tools and is disposed parallel to the adjacent side of the bag between the aforesaid opposed sides.

An arrangement of this character has the important advantages that the slits required for insertion of the binding strip are made in the intended bag walls before the binding strip is actually introduced, thereby positively precluding tearing of these walls such as frequently occurs when the slits are made only by the binding strips themselves.

In a preferred arrangement the pairs of cutting tools are disposed on a common carrier, are spaced from each other by a specific amount corresponding to the distance between the slit sides of the bag, and each comprises a preferably curved, knife-like blade and an associated anvil, serving as a counter knife, this blade and anvil being oppositely pivotable about a common axis.

The anvils will advantageously each be provided at the end with a surface recess of groove form of a width corresponding to that of the associated cutting blade and forming a guide for the binding strip which is to be pushed in after the cutting procedure.

The guide plate referred to is best adjustably secured in the device so that, in conjunction with the recesses in the anvils, there will be a guide means at all sides for the inserted binding strip, and in addition there will be a support for the wall of the bag adjacent the binding strip.

Moreover at least the end part of the guide bar located at the entry for the binding strip can be rounded or bevelled and thereby form, in conjunction with the cutting blade at this side, a sort of introductory funnel for the inserted binding strips.

Yet another feature of the invention lies in the rounding or bevelling of that part of the surface recess in the anvil at the outer side, which faces the entrance, such that this part of the recess is enlarged funnelwise towards the inlet side.

A preferred embodiment of the device according to the invention is described below by way of example in reference to the accompanying diagrammatic drawings, without the invention being restricted to the details shown in this example.

in the drawings:

FIGURE 1 is a front view of the device, with the guide plate omitted,

FEGURE 2 is a broken plan view of the device seen in FIGURE 1,

FEGURE 3 is a side view of the device, and

FIGURES 4 and 5 show the bag in respective view in various phases of formation of the closure.

In the preferred embodiment of the invention illustrated there is a set of tools which is detachably or replaceably associated with an automatic packing machine (part only of which is shown) and is adapted to be moved against and away from the bag mouth 1. This tool set substantially comprises two pairs of cutting tools, the tools of each being movable one relative to the other in scissors fashion. Each such pair consists of a curved cutting blade 2 and an associated counter blade or anvil 3. The cutting blades 2 and anvils 3 are secured to bellcrank levers 4- and 5 respectively, which are relatively pivotable in pairs, about respective common pivots A on a carrier 6 which supports the complete set of tools.

Preferably, carrier 6 has a coupling element B which is arranged centrally between the two said pivots A and serves to transmit to the tool sets the required movements thereof relatively to the mouth of the bag to be pierced. These movements of the tool set are obtained, through a cam plate 15 and a lever 16, which is articulated to the coupling element B, from the main drive of the machine. Preferably, element B is movably mounted in a slideway 13 on the machine frame 17 at the appropriate station.

The anvils 3 of the paired tools have grooves 8 aligned with the associated cutting blades 2, and the cutting edges 7 of the latter are arranged to penetrate partially into these grooves during their movement relatively to the anvils 3.

To make the slits or perforations in the walls of the bag required for insertion of a binding or fastening strip 9 as stated, the tool set is moved towards the open mouth of the bag by tool carrier ti and the coupling element B so that the two narrower sides of the open mouth of the bag pass between the respective pairs of anvils 3 and the cutting blades 2 (see FIGURE 2). The anvils 3 and the cutting blades 2 are then pivotally moved toward one another by the associated bellcrank levers 4 and 5 so that the anvils 3 hear, from the inside, against the narrower sides of the bag 1 and present counter edges to the cutting edges 7 of the blades 2 piercing the walls of the bag.

To enable the cutting blades 2 and the anvils 3 to be operated simultaneously from a single initiating movement only, the bellcrank levers 4 and 5 thereof are provided, via the pivots A thereof, with angularly offset ex tensions 2d, 21 which are coupled together in pairs by links 22, viz. the bellcrank lever 4 of the cutting knife 2 of one pair of tools is coupled to the bellcrank lever 5 of the anvil 3 of the other pair of cutting tools. Moreover, the two bellcrank levers 4i, 5 beneath the tool carrier 6 are pivotally connected together by means of a further link 23, extending transversely between the two pivots A, to produce a motion counter to that first applied. This movement is imparted to the extension 21 of one bell- =3 crank lever which carries a roller 24, from a U-sh'aped part 25 surrounding the roller 24. This part 25 is fastened to a lever 26 which is operated from the main drive of the machine through a face cam 27.

In the position of the

cutting tools

2, 3 illustrated in FIGURES 1 and 2 of the drawings the binding strip 9, made of a suitable material, is fed in the direction of arrow a, by means of a feed device associated with the machine and not here shown. The feeding device is well known and needs no further amplification. This binding strip 9 passes through the two slots made in the walls of the bag, the cutting blades 2 in the grooves 8 of the anvils 3 providing guide means for this purpose. It is immaterial whether binding strips already cut to length are fed in or whether an endless strip is inserted from a reel or other supply to the required length and then cut off.

After the binding strip 9 has been inserted in the prescribed fashion, the tool set, under the influence of the cam disc 15, makes a return movement in the opposite direction out of the mouth of the 'bag, as soon as engagement has been broken between the

cutting tools

2, 3 and the walls of the bag. The bag equipped with a binding strip and held in a container 28 of the conveyor mechanism of the machine, for example a conveyor chain 29, can now be carried in a manner as shown in FIG- URE 4 to a further operating station in the machine, where it can be discharged from the latter after its closure and sealing of the closure by turning over the ends of the binding strip 9. A closed bag with turned over ends is shown in FIGURE 5.

It has proven advantageous to assist the guidance of the binding strip 9, during its insertion into the slits in the walls of the bag, by an additional guide plate 11. This plate 11 is arranged on the machine, from case to case stationary or preferably adjustable by means of screws 30 in relation to the ends of the anvils and in front of the bag mouth 1, and has a rounded portion 1% particularly at the entrance end for the binding strip 9 but conveniently also at the departure end for the same, and this rounded portion, in co-operation with the curved outer surface of the related cutting blade 2, and also in conjunction with the recesses in the anvils 3, constitute flared inlets for the binding strips 9.

Advantageously, to ensure proper guiding of the binding strip 9 into the two slits in the bag wall, a flared enlargement is provided at the inlet end of the groove 8 of the anvil 3 which is to accept the free leading end of the binding strip 9 after the passage of the latter through the first slit in the bag wall.

What I claim is:

1. Apparatus for forming slots in a bag adjacent an open end thereof to permit installation of a fastening strip into said slots, said apparatus comprising a carrier vertically movable towards the open end of the bag, two pairs of cutting tools mounted on said carrier in spaced location for providing slots in said bag, each pair of tools comprising first and second arms, a common pivot connecting said arms to said carrier, a cutting blade on one of said arms, an anvil on the other of the arms, the common pivots of the tool pairs being spaced on said carrier, means for moving the carrier and the tools therewith relative to the bag to a position corresponding to a desired position of the slots, the bag having end walls, the anvil and the cutting blade of each tool pair being respectively located on opposite sides of the end walls of the bag, means for producing relative movement between the blade and anvil of each pair of tools to form said slots in the walls of the bag, said bag with the thusly formed slots therein being adapted for accommodating and supporting a fastening strip therein, and means cooperating with the cutting tools to form a guide for entry of the fastening strip into said slots.

2. Apparatus as claimed in claim 1, wherein the means for producing relative movement between the #blade and anvil of each tool pair includes a mechanical link-age connected to the tool pairs to produce opposite pivotal movement of the cutting blade and anvil of each cutting tool to move each blade into a groove provided in the associated anvil.

3. A device as claimed in claim 1, in which the cutting blade and anvil of each tool pair are cooperatingly formed to provide a guideway for the fastening strip.

4. Apparatus as claimed in claim 1, wherein the means forming a guide with the cutting tools comprises a guide member positioned exteriorly of the bag and adjacent the cutting tools with the latter in position to provide the slots, said guide member and cutting tools forming a guideway for said fastening strip.

5. Apparatus as claimed in claim 4, comprising means adjustably supporting said guide member for movement towards and away from said cutting tools.

6. Apparatus as claimed in claim 1, wherein the means for forming a guide for the fastener strip comprises a guide member positioned exteriorly of the bag and adjacent the cutting tools with'the latter in position to provide the slots, each said anvil having a groove for accommodating the corresponding cutting tool, said guide member extending beyond the groove of each of the anvils to form with said groove and the corresponding cutting tool a guideway for said fastener strip.

7. Apparatus as claimed in claim 6, wherein said groove of one of the anvils is flared to facilitate entry of the fastening strip thereinto and into the corresponding slot.

8. Apparatus as claimed in claim 1, wherein said guide member is of reduced thickness beyond the bag walls to form a flared inlet to facilitate entry of said fastening strip into said guideway.

References Cited in the file of this patent UNITED STATES PATENTS Canada May 6, 1958