GB2068883A - Rotary conveyor for wrapping rod-shaped commodities - Google Patents

Abstract

A rotary packing conveyor for rod-shaped bakery products has a plurality of chambers 2. Devices provided for feeding wrapping material and the products to the chambers. Each chamber is associated with a respective pair of pivotal folding elements 16a, 16b, which can be moved away from each other for the purpose of opening and toward each other for the purpose of closing and each of which has a folding surface to further drape the commodities with those wrapping material sections which extend from the chamber and form part of the wrapping material that already partially surrounds the commodity in the chamber. The elements also present wrapper-holding surfaces 14a, 14b connected to vacuum. Each wrapper is shaped to the respective chamber by a ram 41 prior to indexing the chamber to a product-receiving station C. At subsequent stations D to I, the longitudinal edges of the wrapper are sealed together and the opposite projecting ends of the formed tube closed by pleating and flattening to complete wrapping. <IMAGE>

Description

SPECIFICATION Rotary packing conveyor for wrapping of rod-shaped commodities The invention relates to a rotary packing conveyor for wrapping of rod-shaped commodities, especially those consisting of a plurality of similar pieces of bakery products, which sheet-like wrapping material, with a plurality of chambers for commodities, with an associated device for feeding of the wrapping material and of the commodities to the chambers and with folding elements for draping the wrapping material around the commodities.

An object of the invention is to wrap rodshaped commodities, especially commodities which consist of discrete pieces of bakery products, in wrapping material (e.g., in sheetlike sections of wrapping material) in such a way that the wrapping material tightly surrounds the commodities.

The invention resides in that each chamber cooperates with a pair of shear-like configurated folding elements which can be moved away from each other for the purpose of opening and toward each other for the purpose of closing and each of which has a folding surface, such folding surfaces being designed to move, during closing, of the folding elements, toward each other and to place against and thereby further drape the commodites in those wrapping material sections which extend from the chamber and form part of the wrapping material that already partially surrounds the commodity in the chamber.

Further developments and further embodiments of the invention are disclosed in claims 2 to 1 2.

The invention will be explained in greater detail with reference to the drawing which illustrates one embodiment. There are shown in Figure 1 a packing turret in accordance with the invention, Figure 7a an enlarged view of a chamber with a pair of shear-like folding elements, Figure 1b a sectional view of a detail of the packing turrent in the region of a chamber, Figures 2a . . 2f a device for closing the front end of a package in different operative positions, Figures 3a ... 3f a schematic representation of a front end closer to facilitate the understanding of the mode of operation of the device shown in Figs. 2a . . 2f, Figures 4a . 4d various stages of folding of the wrapping material.

The packing apparatus which is illustrated in Figs. 1 and 1 a and 1 b has a rotary packing conveyor in the form of a turret 1 which is provided with a pluality of chambers 2 and can be driven by a step-by-drive which is customary in the field of packing machines, e.g., a Geneva movement, not shown, in order to perform advancing steps. The following working stations are adjacent to the turret: A: A feed station for wrapping material B: A preforming station for wrapping material C: A feeding station for commodities to be packed D and E: Sealing stations for the longitudi nal seam of the hose-like wrapping material F: A front end closing station G to I: Sealing stations for sealing of the front end of the finally formed wrapping material K: A removing station for finished packages.

Two advancing rolls 6 draw web-like wrapping material 4 from a reel 3; the leading end of the web 4 is pushed into a guide which consists of two sheet metal guides 7 and 8 and the leading end is severed by a knife 9 which moves toward a counterknife 11 as shown by the double-headed arrow 1 0. The leading marginal zone 1 2a of the thus formed sheet-like wrapping material section 1 2 is pressed against the holding surface 1 4a of a jaw 1 6a of a shears 1 6 by a pressure applying plunger 1 3 which moves back and forth in directions indicated by a double-headed arrow 15; the other jaw of the shears 1 6 is denoted by the character 1 sub. The jaws 1 6a and 1 6b of the shears 1 6 are respectively pivotable about pins 1 7a and 1 7b so that they can move away from each other for the purpose of opening the shears and toward each other for the purpose of closing.

Fig. 1 shows that a discrete one of the aforementioned shears 1 6 cooperates with each of the twelve illustrated chambers 2.

Details of one pair of folding elements which are constituted by jaws 1 6a, 1 6b can be found in Fig. 1a which will be explained below.

The outer sides of the jaws 1 6a, 1 6b respectively carry triangular folding projections 1 8a, 1 8b which are formed with holding surfaces 1 4a, 1 4b for the end sections 1 2a, 1 2b of wrapping material sections 1 2 and the inner sides of the jaws are formed with holding surfaces 1 9a, 1 9b for the commodities 44. Rounded folding surfaces 21a and 21b are provided in the transition zone between the holding surfaces 14a, 19a and 14b, 19b.

Suction ports 22a and 22b respectively extend to the holding surfaces 1 4a and 1 4b. At least the outer regions of the chamber 2 are provided with suction ports 23. The jaws 1 spa and 1 6b are respectively connected with mating gears 24a and 24b. A lever 26 which is provided on the jaw 1 6b carries a roller follower 27 which cooperates with a control cam 29 swingable back and forth by the machine drive in directions indicated by a double-headed arrow 28. When the control cam 29 is moved in a clockwise direction, the roller follower 27 causes the lever 26 and the jaw 1 6b to perform a movement which entails an outward movement of the jaw 16b, i.e., it opens in a manner as shown in Fig. 1a. The gears 24b and 24a transmit such opening movement to the jaw 16a.

Return movement of the jaws 1 6a and 1 6b to closed positions (illustrated at the stations C I in Fig. 1) is effected by non-illustrated return springs which are respectively secured to the pins 1 7a and 1 7b and whose resetting effect is felt as soon as the control cam 29 is caused to swing in a counterclockwise direction.

Fig. 1 b shows the deepmost portion 2a of a chamber 2 with a back support 39 which constitutes a biasing strip. The back support 39 is secured to a guide rod 31 which is reciprocably mounted in a guide sleeve 32 disposed in the turret 1. The back support 39 is held in the deepmost portion 2a of the chamber 2 by a roller follower 33 which is mounted in the guide rod 31 and a control cam 34 against the action of a compression spring 36. When the control cam 34 is swung in a counterclockwise direction, the roller follower 33 is released so that the compression spring 36 can move the back support 39 from the deepmost portion 2a of the chamber 2 and to yieldably urge the back support against the wrapping material 1 2 or the commodity 44 to be packed in the interior of the chamber.The back support 39 then urges the commodity against the holding surfaces 1 9a and 1 9b (when the shears 1 6 is closed) so that the wrapping material and the commodity are fixedly held in the chamber 2.

During that advancing step of the turret 1 which follows the feeding of wrapping material at the station A, the severed wrapping material section 1 2 which contacts the holding surface 14a is withdrawn from the guide 7, 8 so that, when the advancing step is completed. The trailing end 1 2b of the section 1 2 lies against the holding surface 1 4b of the jaw 1 6b of the shears 16.

The wrapping material section 1 2 which is then located at the preforming station B is pushed into the chamber 2 by a ram 41. To this end, the ram 41 performs a back-andforth movement in directions indicated by the double-headed arrow 42. Owing to the shaping movement of the ram 41, the wrapping material section 1 2 in the chamber 2 is imparted a partially cylindrical shape. The still free trailing end of the wrapping material section 1 2 is biased by a folding projection 43 of the ram 41 against the holding surface 1 4b of the jaw 1 6b where it is held by suction air, the same as the leading end on the holding surface 14a.Deformation of the wrapping material section 1 2 which is effected in the chamber 2 by the ram 41 is maintained by suction ports 23 in the chamber proper.

The commodity 44 to be wrapped is delivered to the turret 1 at the feeding station C.

This commodity consists of a plurality of round or polygonal bakery products which are disposed one behind the other and together constitute a "bar". It is clear that the "bar" to be packed can also consist of other material which need not be subdivided.

Contrary to the illustration of the shears 1 6 at the station C, the admission of commodity to be packed takes place in open positions of the jaws 16a, 1 6b which are moved away from each other for the admitting step in a manner as shown at the stations A and B. The transfer device is disposed behind the turret 1. It consists essentially of a pusher 46 which is indicated by broken lines and is movable back and forth in the axial direction of the commodity 44. For example, the pusher can push the commodity 44 into the chamber 2 from a compartmented belt of the type known from the field of packaging foodstuffs.Since the jaws 16a, 1 6b of the shears 1 6 are open during transfer, a back support 47 is moved toward the chamber 2 to support the transferred commodity in the radial direction. The front surface of the back support 47 in the holding position of the latter is indicated by a phantom line. A non-illustrated drive moves the back support 47 at predetermined intervals in directions indicated by the doubleheaded arrow 48 in such a way that the back support is held in the supporting position while the commodity is being transferred whereupon the back support is moved away from the chamber 2 after the jaws 16a, 1 6b of the shears 1 6 assume their closed positions.

During closing of the jaws 16a, 1 6b of the shears 16, the marginal zones 12a, 1 2b of the wrapping material section 1 2 which overlie the holding surfaces 14a, 14b slide along such holding surfaces so that, as a result of closing of the shears, the wrapping material is tightly applied around the commodity 44.

This is supported by the resiliently biased back support 39 which is then also pressed radially outwardly and against the commodity 44. At the conclusion of the closing operation, when the wrapping material and the commodity are held by the shears 1 6 and back support 39, the holding air in the holding surfaces 14a, 1 4b is disconnected so that the marginal zones of the wrapping material section 1 2 are released and extend outwardly.

After the turret 1 completes an advancing step, the commodity and the wrapping material reach the sealing station D which is adjacent to stationary closing tongs 49 with heated jaws 49a, 49b. The jaws are movable in the directions which are indicated by a double-headed arrow 51 toward the outwardly extending marginal zones of the wrapping material section 1 2. They press such zones together and thereby seal the zones to each other to thus form a hose consisting of wrapping material and tightly conforming to the commodity. Instead of a sealing operation which presupposes the use of a suitable sealable wrapping material, one can also employ a conventional paster.

After the turret 1 has completed a further advancing step, the commodity with the wrapping material which forms a hose and tightly surrounds the commodity reaches the sealing station E. At this station, there is provided a stationary heated pressing means 52 whose front edge is located closely above the commodity so that it folds the outwardly extending marginal zones of the wrapping material section which were already sealed to each other at the station D while the commodity advances into the station E. As soon as the turret 1 comes to a halt, the pressing means 52 is moved toward and away from the folded-over marginal zones in the direction of the double-headed arrow 53 under the action of a non-illustrated drive.When in the end position nearest to the commodity, the heated pressing means 52 presses against and seals the folded-over marginal zones to the peripheray of the tubularly conforming wrapping material.

If the utilized wrapping material is not sealable, here, too, the sealing device can be replaced with a conventional paster.

After having advanced through the stations A to E, and as already explained hereinabove, the wrapping material is shaped to extend round the commodity in such a way that it forms a tightly adhering hose S whose end portions extend beyond the commodity.

After the turret 1 has completed a further advancing step, the commodity and the hoselike conforming wrapping material reach the front end closing station F at which the ends are sealed at both sides. In this connection, reference will be made to Figs. 2a to 2f and 3a to 3f as well as to the corresponding description.

As a result of the next-following three advancing steps, the completely folded packages reach the stations G and I at which discshaped sealing jaws 54 are pressed against the end faces of the packages during the periods of dwell to thereby attach the overlapping flaps of the wrapping material to each other. The heated sealing jaws 54 are movable toward and away from the end faces of the packages with axially reciprocable plungers 56.

Instead of resorting to a heat-sealing technique, the flaps which overlie each other at the ends can be connected to each other by adhesive.

After completion of two additional advancing steps, the by now finished package reaches the removing station K at which the jaws 16a, 1 6b of the shears 1 6 are moved to open positions so that the package can roll downwardly between the parts of a guide 57 and onto a compartmented belt 58. Removal of the finished packages is assisted by the back support 39 which is moved radially outwardly into the chamber 2.

In a manner which will be described below with reference to a discrete commodity and a section of wrapping material, the commodities and sections of wrapping material which are delivered seriatim to the chambers 2 are processed one after the other so that material is continuously delivered to the packing turret 1 and material is continuously removed therefrom.

The device for closing the ends of a package which is shown in Figs. 2a ... 2f comprises a carrier 101 which consists of a disc 102 and a ring 103, the parts 102 and 103 being held at a fixed distance from each other by braces 104. The carrier 101 is secured to the piston rod 106 of a pneumatic displacing element 107 whose cylinder 108 is fixedly mounted. By controlled activation of the displacing element with compressed air, the piston rod 106 can move the carrier 101 back and forth in directions indicated by a doubleheaded arrow 109, i.e., toward and away from the commodity 44 in the hose S which is formed by the wrapping material section 1 2. At such time, the commodity and the hose S are held in a chamber 2 of the packing turret 1 the details of which are shown in Figs. 1 a and 1 b and which, therefore, are omitted in Figs. 2a .. 2f for the sake of clarity.

That side of the disc 102 which faces away from the displacing element 107 is secured to a further pneumatic displacing element 111 only the cylinder 11 2 and the piston rod 113, which latter is non-rotatably guided in the cylinder, can actually be seen. Compressed air connections 11 4 (to move the piston rod 11 3 in the direction of the arrow 11 6) and 11 7 (to move the piston rod 11 3 in the direction of the arrow 11 8) serve for controlled activation of the displacing element 111 with compressed air.The piston rod 11 3 is connected with a disc-shaped holder 11 9 which carries a star-shaped group of equidistant vanes 121 with forming edges 1 22. The inner diameter of the ring 103 exceeds the diameter of the hose S as well as the diameter of the forming edges 1 22 (the latter form a circle).

The ring 103 carries pivots 1 23 which support folding members 1 24 and are arranged in such a way that each folding member 1 24 can be pivoted inwardly between two vanes 121. For the sake of clarity, only one of the folding members 124, together with a drive 126, is actually shown in the drawing.

However, in actuality, such folding members are distributed along the inner side of the ring 103.

The folding member 1 24 consists of a triangular folding plate 1 27 and a plate-like lever 1 28 which is disposed at right angles to the plate 1 27. The plate-like lever 1 28 is articulately (namely, by means of joints 146 and 147) connected by a coupling rod 1 29 with the piston rod 131 of a pneumatic displacing element 1 32 whose cylinder 1 33 is secured to the disc 1 02. Compressed air connections 134 (to move the piston rod 1 31 in the direction of the arrow 136) and 1 37 (movement of the piston rod 1 31 in the direction of the arrow 138) serve for controlled activation of the displacing element 1 32 with compressed air.A ring-shaped tension spring 141 which extends through an eyelet 1 39 of the coupling rod 1 29 is also guided through the eyelets of coupling rods for all other folding members 1 24. The spring 141 acts in such a way that it urges the coupling rods 1 29 inwardly. The periphery of the disc 102 is formed with teeth 1 42 which mesh with the teeth of a pinion 143. The machine drive can rotate the pinion 143 in such a way that the pinion rotates the carrier 101 back and forth in the direction indicated by a double-headed arrow 144 through a predetermined angle.The length of the pinion 143, as considered in the axial direction, is selected in such a way that the teeth 142 of the disc 102 remain in engagement with the pinion 143 during movement of the displacing element 107.

The compressed air connections of the displacing elements 107, 111 and 1 32 can be connected with a source of compressed air by non-illustrated valves whose mechanical or electrical actuating elements can be operated by cams connected with the machine drive.

The apparatus which is illustrated in Figs.

2a ... 2f serves solely for closing one end face of a package. A similarly designed apparatus, not shown, serves to close the other end face.

The operation of the apparatus shown in Figs. 2a . . 2f for closing of the ends of a package: In connection with description of the mode of operation, reference will be made, in addition to Figs. 2a ... 2f, also to Figs. 3a ... 3f which show the different operative positions of the folding plates 1 27 of the folding members 1 24 as well as to different positions of the holder 11 9 with forming edges 1 22. The effects which the individual folding operations produce upon the commodity are illustrated in Figs. 4a ... 4d.

In the description of the mode of operation, the closing of only one end will be described.

The closing of the end at the other side takes place in similar fashion.

In describing the sequence of folding operations, reference will be made first to Fig. 2a which shows the apparatus for closing the ends in starting position. Figure 3a shows all of the folding plates 127; for the sake of ready recognizability of the overall configuration, the corresponding holder 11 9 is shown separately.

In the first step, the cylinder 108 of the displacing element 107 receives compressed air via compressed air connection 148 in such a way that the piston rod 106 is moved toward the hose S of the wrapper whereby it moves the entire carrier 101 with all folding members 1 24 and their drives 1 26 as well as the holder 11 9 with the forming edges 1 22 toward the hose S. The position which is reached upon completion of such movement is shown in Figs. 2b and 3b. In such position, the ring 103 is located substantially at the level of the front end face 44S of the commodity 44 while the vanes 121 have penetrated into the extension S' of the hose.

All cylinders 1 33 of the drives 1 26 which constitute the displacement elements 1 32 for the folding members 1 24 simultaneously receive compressed air by way of the corresponding compressed air connections 1 37 so that the piston rods 1 31 are retracted into the cylinders 1 33. The folding members 1 24 turn about the pivots 1 23 by way of the coupling rods 1 29. The pivotal movement is thereby limited by the disc-shaped holder 11 9 so that the plate-like lever 1 28 and the coupling rod 1 29 do not assume their extended positions, i.e., they still make an angle (Figs. 2c, 3c).

The folding plates 1 27 are simultaneously pressed against the extension S' of the hose whereby the extension S' develops equal sections 1 51 which are equally distributed at the circumference of the front end of the commodity 44 and are at the same time pressed in a direction toward the front end face 44S of the commodity 44. The fold lines 1 52 thereby form generatrices of the frustum of a cone. The folding edges 1 22 ensure that webs 1 53 extend outwardly between the fold lines 1 52 and the outer boundary lines 1 54 of such webs form the generatrices of a second conical frustum.In this manner, the wrapping material of the extension S' is converted into a conical frustum 1 56 with a corrugated surface (Fig. 4b).

The cylinder 11 2 of the displacing element 111 receives compressed air via compressed air connection 11 7 so that the piston rod 11 3 moves the holder 119 with the vanes 121 away from the extension S' of the hose. The disc-shaped holder 11 9 thereby releases the coupling rods 1 29 so that the coupling rods and the plate-like levers 1 28 assume their extended positions (Fig. 2d). In the next step, the compressed air connections 1 34 of the cylinders 1 33 receive compressed air one after the other (the compressed air connections 1 37 are vented in the same sequence) so that the folding plates 127with support from the tension spring 141successively press the depressed sections 151 of the extension S' of the hose against the end face 44S of the commodity 44 (Figs. 2e, 3d). In this manner, the sections 151 are converted into triangular segments which are adjacent to the commodity 44 and alternate with outwardly extending triangular webs 1 53 of the extension.These webs constitute folded flaps which diverge in a direction toward the center of the end face and have an at least substantially triangular configuration. The longest lateral edges (fold lines 152) of such folded flaps extend substantially in the radial direction of the front end face 44S and are somewhat longer than the radius of the front face.

As a result of placing of successive folding plates 1 27 against the front end face 44S and the aforedescribed formation of segments and folded flaps, the segments resp. the tips of the folded flaps overlap each other; this causes the folded flaps to lie slightly askew with reference to the front end face 44S which is not shown in the drawing. The pinion 1 43 is thereupon caused to rotate whereby it turns the carrier 101 clockwise through a predetermined angle by way of the teeth 142 (Figs. 2f, 3e). In this manner, the triangular folded flaps (webs) of wrapping material are folded over in a direction such that they overlap each other adjacent to the front end face of the commodity.Fig. 4d shows that, upon completion of such folding, the tip of each and every folded flap 1 53-as considered in the direction of folding--over- lies a neighboring folded flap.

Upon completion of such total closing of the front side of the package P, the cylinder 108 of the displacing element 107 is supplied with compressed air via compressed air connection 1 49 in such a way that the piston rod 106 is moved away from the package P to thereby entrain the carrier 101 with the folding members 1 24 and their drives 1 26 as well as the holder 11 9. The pinion 143 is thereby driven to rotate the opposite direction so that the carrier 101 is rotated counterclockwise back to its starting position by way of the teeth 142 on the disc 102.

Simultaneously with movement of the carrier 101 away from the package P and its rotation back to starting position, the compressed air connections 1 37 of the cylinders 1 33 in all displacing elements 1 32 receive compressed air (the compressed air connections 1 34 are vented) so that the piston rods 131 are retracted and the folding members 1 24 are pivoted, by way of the coupling rods 129, back to the positions corresponding to those shown in Fig. 2d.In the next step, the compressed air connection 11 4 of the displacing element 111 receives compressed air (the compressed air connection 11 7 is vented at the same time) so that the piston rod 11 3 and the holder 11 9 move in the direction of the arrow 11 6. The circumferential edge of the holder 11 9 thereby presses the coupling rods 1 29 outwardly against the opposition of the spring 141 (to a position corresponding to that of Fig. 2c) which is made possible by venting of the compressed air connections 1 37 of the displacing elements 1 32. Immediately thereafter, the compressed air connections 1 34 of the displacing elements 1 33 are again connected with the source of compressed air so that the piston rods 1 31 pivot the folding members 1 24 back to their starting positions (Figs. 2a, 3f) by way of the coupling rods 129.

In the meantime, the completely folded package P in a chamber 2 of the packing turret 1 has advanced into the range of the first sealing station G, as considered in the direction of transport, wherein the overlapping parts of the wrapper (folded flaps 153) are connected to each other by heat-sealing.

As shown in Fig. 4d, the closure at the front end of the finished package P is quite uniform owing to the regularly formed folded flpas which overlie each other in an imbricated pattern so that the appearance of the front end is esthetically satisfactory.

Claims (11)

1. A rotary packing conveyor for wrapping of rod-shaped commodities, especially those consisting of a plurality of similar pieces of bakery products, with sheet-like wrapping material, with a plurality of chambers for commodities, with an associated device for feeding of the wrapping material and of the commodities to the chambers, and with folding elements for draping the wrapping material around the commodities, wherein each chamber cooperates with a pair of shear-like configurated folding elements which can be moved away from each other for the purpose of opening and toward each other for the purpose of closing and each of which has a folding surface, such folding surfaces being designed to move, during closing of the folding elements toward each other and to place against and thereby further drape the commodities into those wrapping material sections which extend from the chamber and form part of the wrapping material that already partially surrounds the commodity in the chamber.

2. Packing conveyor according to claim 1, wherein it constitutes a turret which can be driven in stepwise fashion, which carrier the chambers and to which are secured pivots which support the folding elements and about which the folding elements are pivotable between open and closed positions in dependency on a control cam.

3. Packing conveyor according to claim 1 and/or 2, characterised by the provision of a stationary cam which conforms to the shape of the chambers and is disposed in the region of feeding device for wrapping material, the ram being movable into and thereupon out of a chamber for the purpose of shaping the wrapping material.

4. Packing conveyor according to one or more preceding claims, wherein at least the outer end regions of each chamber are provided with suction channels to hold the wrapping material.

5. Packing conveyor according to one or more preceding claims, wherein the folding elements comprise holding means for those sections of wrapping material which are adjacent to the folding surfaces.

6. Packing conveyor according to claim 5, wherein the holding means constitute holding surfaces with suction channels.

7. Packing conveyor according to one or more preceding claims, wherein a section of a folding surface which faces the chamber constitutes a holding means for the commodity.

8. Packing conveyor according to claim 7, characterised by the provision of a pressure applying strip which is located in the deepmost part of each chamber, which is yieldably movable toward the commodity in the chamber in closed positions of the folding elements and fixes the wrapping material on the commodity in cooperation with those sections of the folding elements which constitute the holding means.

9. Packing conveyor according to one or more preceding claims, characterised by stationary closing tongs for connecting to each other those end sections of the wrapping material section which extend from the commodity.

10. Packing conveyor according to claim 9, wherein the closing tongs comprises heated jaws for sealing of the end sections.

11. Packing conveyor according to one or more preceding claims, characterised by stationary pressing means for holding of interconnected end sections of the wrapping material which extend from the commodity and for attaching such end sections to a portion of wrapping material which already surrounds the commodity.

1 2. Packing conveyor according to claim 11, characterised by heated pressing means for sealingly securing the end sections to the wrapping material which already surrounds the commodity.

1 3. A rotary packing conveyor for wrapping of rod-shaped commodities, substantially as herein described with reference to and as illustrated in the accompanying drawings.