WO1981001543A1

WO1981001543A1 - Procedure and apparatus for positioning valve bags onto filling machine spout

Info

Publication number: WO1981001543A1
Application number: PCT/DK1980/000077
Authority: WO
Inventors: E Berthelsen
Original assignee: Bates Ventilsaekke; E Berthelsen
Priority date: 1979-12-04
Filing date: 1980-12-04
Publication date: 1981-06-11
Also published as: GB2078189B; NO156197B; SE8104465L; DE3050072T1; CH660469A5; DK147636B; SE448363B; BR8008877A; DK514879A; FI62264C; NO811832L; GB2078189A; AU540719B2; RO84548A; NL183930C; NL183930B; HU200301B; FI812299L; NL8020459A; DE3050072C2

Abstract

The positioning of a valve bag onto a filling spout comprises the retaining of the valve of a bag and a subsequent insertion of an insertion member (2) into the mouth of the stationary bag and a distention of the opening, the gripping around the distended valve by means of a gripping member (3), withdrawal of the insertion member, and a bringing together of the valve opening and the filling spout (4). The apparatus designed to carry out the invention comprises an insertion member (2), a gripping member (3) and means to move these members in accordance with the method.

Description

Procedure and apparatus for positioning valve bags onto filling machine spout

This present invention concerns a procedure and en apparatus designed for the positioning of valve bags onto a filler machine spout. The procedure is of the kind where the individual bags are grasped and taken through a process in order to open the valve of the bag, whereafter the valve opening is fitted onto the filling spout, and held in readiness to fill the bag.

Background Art.

There are several ways to position valve bags onto a filling machine spout according to prevalent technology.

Automatic positioning apparatus used so fer first positively open the valve portion of the bag, and then place the valve opening over the spout, the letter taking place by either positioning the valve portion of the bag over the spout, or, alternatively, by bringing the filling spout into the valve opening.

One known metnod of positioning bags involves the opening of the valve by means of suction cups, contacting and grasping the beg along two lines parallel to the edges of the valve.

By tilting the positions of the two lines of suction cups in such a manner that the midole part of the top portion forms an upward facing back, the valve is forced to open, and in the resulting position the bag can be brought into contact with the filling spout. Another method to open the valve is one where the suction cups are merely used to keep the upper layer of the top portion tight in a certain position, whereupon an insertion member is brought to press against the underlying layer near the valve mouth and thereby tearing the valve open.

Likewise, suction cups have been used in a known apparatus where the bags, in a flat and stretched position, are grasped and kept stationary by suc tion cups at the side of the bags. Other, moving suction cups, placed on the valve itself, can then rip open the parts of the valve, giving room for the insertion of the filling spout.

Finally, compressed air can be used to open the valve. The tε.chnique involved here positions the valve portion of the bag tight against a surface, and a nozzle directed at the valve mouth forces it open by means of a high-pressure discharge of air, facilitating the insertion αf the filling spout. These known methods employed in automatic filling appliances all have a number of drawbacks, which this, present invention tries to avoid. The use of suction cups to keep the bags in position and to open the valve portions of the Decs necessitates the utmost uniformity of bags and exact positioning if the suction cups are to get a firm grip.

It has proved difficult to ensure with certainty a perfect opening of beg valves when using suction cups as folds end similar irregularities, which may arise when glueing the top portion αf the bag, tend xo reduce the gripping ability of the suction cups, end, in sorπ cases, a firm hold will be quite impossible. During tne proαucεiαn of bags it sometimes happens that excess application of glue will cause the actual valve opening to jam. Such bags could very well be used if only the valve is forced open before reaching the filling spout. The known techniques involving the use of suction cups and compressed air from a nozzle frequently fail to open such bags with glued valves, and the bag will have to be taken out, the otherwise cαntinous and automatic filling will be disturbed, in certain filling lines causing loss αf materiel, as the absence of a bag with open valve will have the effect that material simply pours out vjithout control.

It is the purpose of this invention to avoid the drawbacks mentioned above, and to delineate a method and an apparatus which will ensure positive, complete, and maximum opening αf the valve, and also a certain and perfect contact with the filling spout.

Disclosure of Invention.

This is achieved by means of a method according to claim 1, comprising the following steps, a) securing, at least, the top portion of the bag provided with valve, b) inserting an insertion member into the valve αpeneing to ensure a maximum utilization αf the diameter, c) gripping, by means of a gripping member, the valve of the bag, preferably near the mouth of the still fully open valve, d) withdrawal of the insertion member, ε) bringing together, by means of the gripping member, the bag and the filling spout, the letter being inserted into the open valve opening. It seems quite obvious that the utilization of this method will ensure that even bags with glue in the valve opening will be forced open at the insertion of the insertion member through the mouth of the valve. The sub sequent gripping by a gripping member round the valve will keep the bag valve at maximum opening and diameter, as the parts of the valve are forced to follow the movements of the gripping member surfaces facing the valve. Having withdrawn the insertion member from the valve, the valve can be brought into contact with the filling spout, either by letting the gripping member take the bag to a stationary filling spout, or by inserting a filling spout into the valve opening while the valve is kept stationary.

The apparatus, designed to perform the method in accordance with claim 1 end of the. kind where there is a retaining member to retain the top valve portion of the bags at least, and a distention member to stretch the velve opening, is unique in that it comprises a mobile insertion mernDer with at least one forward wedge-shaped part designed to enter, through a progressive movement of the insertion member flush with the retained portion of the bag, into the mouth of the valve, and also in that said insertion member is designed in such a way that, when fully inserted, it has a cross-section, at least near the edges of the valve, which essentially distends the valve opening, end also a gripping member provided with mobile claws designed to grip or clasp the distended valve near the edges of αf the valve mouth, which claws when gripping are provided with surfaces of a form which, by and large, is similar to the cross-section of the insertion member at the point in question. In spite of its simple construction, this apparatus ensure a complete opening of the valves of the bags. The description shows that the valve opening is forced open through insertion of the insertion member, and even if some residual glue should cause the valve to stick together full distention of the opening will be achieved as a result of the fact that, when fully inserted, the insertion member has a cross-section equal to the size of the mouth of a valve when fully open.

An improved version of the insertion member is achieved if designed, as in claim 3, in the fashion where the insertion member is composed of a number of movable parts which, in one position, together form the progressive wedge-shaped portion, and which, in a different position, form a cross-section constant throughout its length essentially and preferably circular and of a size equal to the exact size αf the fully distende valve opening.

Using the above insertion member, the distention of the valve mouth is effected by first letting the forward wedge-shaped portion of the insertion member progress in through the mouth of the valve. This causes the mouth to stretch and further makes possible the second position of the insertion member where the individual parts of the insertion member change their mutual position in such a way that an overall, extended shape αf the insertion member is achieved., i.e. the cross-section of the insertion mεmoer is increased, the

causing the valve opening to positively stretch.

An especially recommendable embodiment αf the insertion member is descriced in claim 4, where the insertion mem ber consists of two elonga tecpsrts, both provided with a forwerdly pointec portion and a r e a r portion provided with, at least one part, a hinged connection so that it may be positioned in such a way that the two forward portions form together the progressing portions, or alternatively be positioned in a way where the two insertion parts are essentially parallel, in which second position they form a shape in a size similar to that of a fully distended valve bag opening, and furthermore that the insertion embers are mobile length wise, or at least one insertion part.

Thus, a simple and effective insertion member is achieved which, when in one position, is able to penetrate the mouth of the vεlve, and, when in the second position, is able to increase its shape so as to cause the full and complete opening.

In the event where the insertion parts are designed, as described in claim 5, in such fashion that the insertion parts take the shape of halved cylindrical shells, pointed forward, and positioned with interfacing concave surfaces, the distention of the valve opening will reach the maximum.

Ideally, the gripping claws and the insertion member are designed in such a manπner that the cross-sections of the insertion member when distended, and the gripping claw surfaces against the valve when in the gripping position, are identical to the cross-section of the filling spout. This will ensure the shaping of the the valve opening corresponding to tr a shape of the filling spout, end further ensure a correct feeding of bags onto the spout.

The circular cross-section is especially preferable because it results in maximum opening as well as the optimum stability of the distended valve. when bags ere stacked it mav be difficult for the insertion member to penetrate properly the valve opening, as the bags are not stretched flat, but arch near the middle. By making the insertion member as e whole pivotable at the rear end round a hori zontal shaft lying across the direction of the progression, the insertion member will be able to follow the shape of the bag and thereby positively ensure penetration into the bag valve.

In case the bag valve is completely glued, or if for some other reason penetration of the insertion member is not possible, it would be expeoient to have the bag removed before the apparatus carries out an entire operation. This is done by providing the insertion member with a sensor to indicate whether the member has penetrated the valve, cr has slipped past. The sensor can be a switch, photoelectric cell, or other known sensor, connected to a device designed to remove the bag. The latter could be an arm provided with suction cups or similar means. Likewise, the sensor is connected to the plant as a whole, and if there is no pulse from the sensor operations will not continue, but the insertion member will go in position to take another beg. Ideally, the sensor can be a toggle switch built into the upward-facing surface of the insertion member, and in case the insertion member penetrates the valve opening, the switch is activated, or vice—versa.

In order to further enhance the penetretion of the insertion member into the bag valve there may be a finger, as indicated in claim 12, which finger exerts pressure onto the portion of the bag in front αf the valve, which will cause the valve to open slightly, and at the seme time keep the bag sta- tionary. For the upper bags αf the stack, the underlying bags will supply the flexibility necessary to open the valve, but the last bags of the stack will need more flexibility than the hard table that form the basis. As indicated in claim 13 it is therefore possible to include a swage or a raised platform with a swage, with or by an elastic material, in such a way as to permit a suppression of the valve mouth. Brief Description of Drawings

One embodiment αf the present invention will now be described by way of example with reference to the accompanying drawings, in which:

Fig. 1 is a side view showing part of a beg fitting apparatus carrying out the method according to the invεntion, the part including the actual insertion member; Fig. 2 is an enlarged projection of the individual parts of the insertion member; Fig. 3 shows the gripping member in the process of gripping an already distende bag valve; Fig. 4 shows the bag fitting machine seen from the front, and Fig. 5 is a fragmentary view of the transporter/ table immediately below the insertion member.

Description of the Preferred Embodiment

A bag fitting apparatus designed for fitting segs onto the spouts 4 of a filling plant 1 comprising, mountec on a coassis not shown an insertion member 2 (figs . 1 and 2) end a gripping member 3 (fig. 4). Th e insertion member 2 , a s d e mo ns tra t e d in f i g s . 1 a n d 2, consisting of two parts 5,6, pointed at the forwardly progressing end, and where one part 5 pivotably connects to a bearing 7 at the rear end. The two parts, εεch taking the shape αf halved cylindrical shells with a pointed end and the two concave insides feeing each other, are shown in the initial position (full lines), where the pointed, forward ends of the two parts 5,6 meet to form an aggregate wedge-shaped insertion portion 2. The mobile insertion portion can be moved by means of a hydraulic or pneumatic cylinder 8, mountεd between the two insertion parts 5,6 into the second position, shown in dot-and-dash lines in fig. 1, where the insεrtion portion are essentially parallel. The insertion portion 2 connects to the piston rod of a horizontally mounted hydraulic αr pneumatic cylinder 9, by means αf which the insertion portion 2 can be made to move horizontally.

The entire errεngement mentioned consisting of insertion portion 2 and the horizontally mounted cylinder 9 will move vertically and can be made to move by means αf the piston rod of a vertically mounted hydraulic or pneumatic cylinder lo.

Thus, the insertion portion 2 is mobile both vertically and horizontally and can be made to take the positions indicated on thε drawing, where, likewise, the mutual positions of thε two insertion parts 5,6 are delineated.

The penetration and distention of a bag is effected in the following manner: Bundles of bags 11 are fed to the b a g f it tin g mac hine b y a trans por ter 12 . Th e b a gs are guided, inter alia by means of a fence 13 (fig. 4) in order that the longitudinal direction of the valve corresponds to thε longitudinal direction of the insertion portion, and that the mouth of the valve complies with the position of the insertion portion.

A retaining member not shown next grasps the edge of thε valve facing the apparatus, and the wedge-shaped insertion member 2 is progressing forward end into the mouth of the valve, forcing it open in the process. Thereafter the hydreulic or pneumatic cylinder 8 is activated, so that the movable insertion part 6 moves out horizontally, thereby distending the valve.

A subsequent activation αf the cylinder lo lifts the distended valve bag to a certain height over thε transporter. In that position, the valve is gripped by the gripping member 3 in the mode hereinafter described: The gripping member (of figs. 3 and 4) consists of an arm 14, connected to a carriage 15. By means of rollers 16 end a tensile force not shewn, the carriage can be made to move horizontally along a girder 17, the. ends of which are mounted in bearings not shown. Thus, the girder can be turned round its longitudinal axis through a hydreulic or pneumatic cylinder 18, whose one end connects to the chassis D, and whose other end, via an arm, is connected to the girder 17.

At the end of the arm αf the gripping member 13 a pair of gripping claws 19, 2o are pivαtably mounted, having inside surfaces which, in the gripping position, are of the same shape as the filling spout 4 and as the cross-sectional shape αf the insertion member when extended, which latter shape is approximately circular. The gripping claws are made in a material such as sheet or plate, and εach claw comprises, as shown in fig. 3, two identical parts, kept together by means of a cross- piece 21 and a connecting shaft 23. The connecting shaft is pivotebly mounted in the arm 14, so that the claw can rotate. To each of the claws a traction bar 24,25 is fitted, the free ends of which hinge together to the piston rod of a hydraulic or pneumatic cylinder 26. The cylinder 26 is mounted inside the arm 14 of the gripping member 3 in its longitudinal direction and will, when activated, move the traction bars 24,25 so as to turn the claws 19, 20 in order that the claws may take a closed, gripping, or open position.

The gripping member is able to make a tilting move ment when activated by the hydraulical or pneumatic cylinder I8, a transverse movemεnt along thε girder 17 by means of a tension device not shown, and a gripping movement with its claws 19, 20 by means of the cylinder 26. When, as already described, a bag arrives by the transporter 12 and has been distended and lifted the insertion member, the distended valve of the bag 27 is clasped by thε two claws 19, 2o αf the gripping member, whereafter the insertion member withdraws to return to its initial position as shown in fig. 1. Next the gripping member is turned by means of the cylinder 18, rotating the girder 17 to a tilted position, as indicated with dot-and-dash lines in fig. 3. In this tilted position, the carriage 15 of thε gripping member is made to move along the girder oy the xension force not shown, until the gripping member is in position with thε filling spouts 4.

The filling spouts are placed under the girder 17 in such a distance that, when the gripping member now rotates back, the gripping member fits exactly over the filling spout, fitting onto the spout the distended valve of the bao 27. A retaining device, consisting of cylinder 28 with a rubber stopper mountεd to thε piston rod, is now activatεd so as to keep tight the bag 27 against the spout 4. By going through thε movements befαrcmεntioned, the gripping membεr next returns to its original position in ordεr to grip a new bag and take it to a new filling spout.

The bags having been fitted, thε materiel in question pours out to fill the bag, whichis supported by the underlying roll 3o.

When thε bag is full, the retaining device 28,29 lets go, and, caused by the position of the supporting roll 3o, thε bag will drop outward and cnto a conveyor bεlt below (not shown).

Thε above description is concerned with a preferred embodiment of an apparatus desigπεd to carry out the method according to this present invention.

Without leaving the original scope of the invention there will be several alternative embodiments of the apparatus.

One such alternative could be that the girder is mounted in a fixed position, and that, in return, the arm of the gripping dεvicε is pivotably mounted on a carriage or in similar fashion. Other designs and shapes of thε claws and their operating and moving parts are possible, and, still within the scope of the invention, an insertion member with several moving parts is conceivable.

Claims

WHAT WE C LA I M I S : -

1. A method for the positioning of valve bags onto a filling spout, which method is of the art where the individual bags are gripped and go through a process designed to open the valve of thε bag, after which process the valve opening is brought to mesh with the spout to fill thε bag, c h a r a c t e r i z e d i n that the method or procedure of opening and positioning thε valvε of thε bag and of bringing it to mesh with the filling spout comprises the following, steps a) retaining at least the top portion of the bag provided with a valve, b) insertion of an insεrtion member into the valve opening in order to distend the latter, c) gripping or clasping by means of a gripping member round the circumference of the valve, preferably near the mouth of thε still dis tended valve opening, d) withdrawal of the insertion member, e) bringing together, by means of the gripping member, the bag and thε filling spout, which filling spout is inserted into the open valve mouth.

2. An apparatus designed to carry out the mεthod in accordance v/ith the invention and of the art which comprises an insertion member for the dittsntiαπ of thε bag valve, gripping members for the gripping and keeping distended the velve, also after the removal of the insertion member from tne valve, whicn gripping members are mounted to a carriage travelling back and forth on a rail or girder between a point where the insertion member distends the bag valvε and a point where the bag is fed onto the filling spout, c h a r a c t e r i z e d i n that the insertion member (b) has members (a) designed to carry out a reciprocal movement, where, in its progressing position the insertion member enters the valve of the bag in order to open the valve, and also members (lo) designed to lift or lower the insertion member (5), where it lifts the insertion member with the bag still hanging suspended by the insertion member, and that the gripping members (3) are pivot ably mounted on the carriage (15), where the gripping member, in its lowered position grips or clasps the valve bag, after which process the gripping member, still and at the same time holding on to the bag, is lifted to a raised position, and also that the rail or girder (17) along which the carriage (15) with the gripping member (3) travels is placed in front of a number of filling spouts (4)with stops in front of thε individual filling spouts, where the layout of rail or rails (15)(17)is such in relation to the spouts that the gripping member (3) in its lowered position will position the bag with its valve over thε filling spouts (4), next to return to the raisεd or lifted position, after which the carriage (15) travels back to the initial position for another bag.

3. Apparatus according to claim 1, c h a r a c t e ri z e d i n that the distention member comprises a) a movable insertion member (2) with at least one forward progressing portion designed to e nter, through a progressive movement of the insertion member (2) level with the top portion of a retained bag (11) , into the mouth of the valve, and which insertion member (2) is further designed in such manner that when fully inserted it has a cross-section, near the mouth of the valve at least, which essentially distends the valve opεning to the maximum. b) a gripping member (3) with mobile claws (19, 2o) designεd to grip round thε distende valve near the mouth, which claws have a surface towards the valve, when in the gripping position, of a shape which essentially corresponds to the cross- section of the insertion member (2) at the relative position.

4. Apparatus according to claim 3, c h a r a c t e r i z e d i n that the insertion mεmbεr (2) is composed of a number of interacting parts which, in one position, form an overall shape to make up a wedge-shaped front portion, and which, in another position, has a shape with an essentially constant cross-section throughout its length, which cross-section is preferably circular and of a size corresponding exactly to the size of the fully distended valve opening.

5. Apparatus according to claims 3 and 4, c h a r a c t e r i z e d i n that thε insertion member (2) consists αf two lengthy parts (5,6) which are both provided with a pαintεd front portion and, at least one of the parts, a rear portion that is pivotably hinged (7) so that it may take up a position where the two front portions form a joint forwardly progrseing and pointed portion, and also another position where they form a shape of a size identical to the size of a fully distended valve αf a bag, and which insertion parts (5,6) are movable in the longitudinal direction of at least one part.

6. Apparatus according to claim 5, c h a r a c t e ri z e d i n that the insertion parts (2) are of a shape like halved cylinder shells, pointed at the forward progressing end, and which have interfacinα concave surfaces

7. Apparatus according to claims 3, 4, or 5, c h a r a c t e r i z e d i n that the underside of the insertion membεr (2) facing down towards the bag valve when sεεn during the penetration of the bag valve is parallel or approximately parallel to the bag valve, that the upward facing surface of the insertion membεr (2) when closed form an angle with the underside between 5 and 35 degrees, that thε front end of the insertion member (2) is rounded whεn sεεn on a top view.

8. Apparatus according to one or several of the claims 3 to 7, c h a r a c t e r i z e d i n that the insertion member (2) as a whole is pivotably mounted et the rear round a horizontal shaft (30) lying across the longitudinal cirection in ordεr that it may freely rαtεte from one stop below horizontal, or slightly below horizontal; and upwards.

9. Apparatus according to one or several of the claims

3 to 8, c h a r a c t e r i z e d i n that the insertion member (2) has a sensor to indicate whether the member has positively entered thε bag valve or has slipped past, and also that the sensor is connected to a device designed to remove the bag should the insertion member have slippεd pest thε bag valve. lo. Apparatus according to claim c h a r e t e ri z ε d i n that thε sensor is dεsigπεd as a toggle switch (32) fittεd into upper surface of the insertion member (2) and in such a way that the front portion is flush with the surface of the insertion member (2) in order that the mεmbεr can unhindεrεd slide into the bag valve.

11. Apparatus according to the claims 3,4, and 5, c h e r a c t e r i z e d i n that thε cross—section of the insertion member (2) when extended, and of the gripping claws (15, 2o) when seeing the inside surface gripping the valve, is of the same shape as the cross- section of the filling spout (4).

12. Apparatus according to claim 7, c h a r a c t e r ¬i z e d i n that the cross-section metioned is approximately circular.

13. Apparatus according to claim 2, c h a r a c t e ri z e d i n that it comprises a table onto which the bags are stacked with the valves facing up, and also comprising an arm (34), for example in the form of an air cylinder (35) mounted at the table below the insertion membεr (5), and which arm at the end is provided with a finger (35) designed to enter over and press down in front of the mouth of the valve of the bag.

14. Apparatus according to claim 14, c h a r a c t e r i z e d i n that the table is provided with a swage or hollow, or a raised platform possibly of or including elastic material (36) at the point where the finger (35) exerts pressure against the valve opening.