EP1259446B1 - Holding clamp and device for conveying flexible, flat objects containing two or several pieces - Google Patents

Abstract

The clamp has two interacting clamp elements (14) which can be moved relative to one another. These are intended for retaining a sheet-like article (70). The clamp (12) also has a holding-open element (20) which is intended for engaging between two parts (78, 78') of the article and, when the clamp elements (14) are located in the closed position (18'), for keeping these parts (78, 78') separate from one another and thus holding the article (70) open.

Description

The present invention relates to a device for transporting two- and multi-part, flexible, flat objects, according to the preamble of patent claim 1.

One intended for transporting two- and multi-part, flexible, flat objects staple of this type is known from EP-A-0 767 125. It has two jaws pivotally mounted on an axle. These are brought into the closed position by means of a closing device and held in this position. The locking device is formed by a pivotable bracket, which has two clamping body, each sitting on a rigid support arm. The two clamping bodies are, in the closed position of the clamping jaws, in a locking recess formed on the outside of the clamping jaws and exert a closing force on the two clamping jaws. By pivoting the locking device from the closed position to a release position, the clamp jaws are released and can pivot, for example, by spring force in the open position. The clamps are intended for holding flat objects, in particular flexible flat objects, such as single-leaf and multi-leaf printed products, and can be guided for transporting the objects along a transport path. Due to the narrow design of the clip, it is particularly suitable for buffering the individually held items.

EP-A-0476859 discloses an apparatus for opening folded printed products. A printed product is introduced into a receiving element and then detected and held by mutually moving, arranged on walls of the receiving element pressing areas. Subsequently, the held printed product is easily opened with a pre-opener and transported in a conveying direction to a rotating, helical opening element, wherein cooperating with the receiving element brackets are in the open position. By a rotary motion of the opening element completely autonomous opening element, the slightly open printed product is opened further. As soon as the opening element engages in a partial opening of a printed product produced by the pre-opener, the respective pre-opener is withdrawn from the engagement. Then the clamps are moved to a closed position to keep the printed product open.

DE 640559C discloses a device for opening folded sheets with a gripper and a relatively hold open holding element, which is designed as a spreader needle. The opening and keeping open is effected by the relative movement of gripper and hold-open element.

CH-A-641113 discloses a method and apparatus for opening multi-sheet products, particularly printed products. The product to be opened is thereby inserted with an open side parallel to an axis of rotation of a rotatable, roller-shaped cellular wheel in a compartment thereof. For this purpose, a carriage which is displaceable parallel to the axis of rotation of the cellular wheel and which holds the product by means of gripper jaws before and during the entire opening process at the fold. at the axial displacement hits the product with a leading, perpendicular to the fold edge on a pivotable stop, which pierces into the product and retains a number of leaves of the product. The retained leaves bulge with continued displacement of the product against the remaining leaves of the product, resulting in a partial opening. In this partial opening then engages a stationary, wedge-shaped hold-open organ. Subsequently, the pivotal stop releases the retained leaves again.

It is an object of the present invention to develop the known device such that it can fulfill further functions.

This object is achieved with a device having the features of claim 1.

In the device according to the invention, a clamp, which is intended to hold an object, is assigned an open-holding element which holds open the object held by the clamp. This allows for a variety of different operations on and processing of the item held by the clip. For example, the open-ended article may be straddled on saddle-shaped pads, or inserts, samples, or the like may be inserted into the open-ended article.

Preferred embodiments of the device according to the invention are defined in the dependent claims.

Fig. 1

in perspektivischer Darstellung eine erfindungsgemässe Klammer mit zwei Klammerelementen und einem Offenhalteelement vor der Übernahme eines mehrteiligen, geöffneten flächigen Gegenstandes, und eine Zuführvorrichtung;

Fig. 2

in gleicher Darstellung wie Fig. 1 die Klammer mit sich in Offenstellung befindlichen Klammerelementen während des Einfahrens des Offenhalteelements in den geöffneten flächigen Gegenstand;

Fig. 3

in gleicher Darstellung wie Fig. 1 und 2 die Klammer mit in Schliessstellung den Gegenstand haltenden Klammerelementen und dem zwischen zwei Teilen des Gegenstandes angeordneten Offenhalteelement;

Fig. 4

in gleicher Darstellung wie Fig. 1 bis 3 die Klammer mit den den Gegenstand haltenden Klammerelementen und mit dem zum weiteren Öffnen des gehaltenen Gegenstandes um etwa 90° in eine Spreizstellung gedrehten Offenhalteelement;

Fig.5

in Ansicht mehrere, je einen flächigen Gegenstand haltende Klammern mit einem Offenhalteelement zwischen jeweils zwei Teilen des betreffenden Gegenstandes, wobei sich die Klammern in einer Pufferstrecke einer Transportvorrichtung befinden;

Fig. 6

in gleicher Darstellung wie Fig. 5 zwei einen Gegenstand haltende Klammern mit in Spreizstellung verdrehtem Offenhalteelement;

Fig. 7

in Ansicht eine weitere Ausbildungsform einer Klammer mit Offenhalteelement in Offenstellung der Klammerelemente;

Fig. 8

in gleicher Darstellung wie Fig. 7 die dort gezeigte Klammer in Schliessstellung der Klammerelemente;

Fig. 9

eine dritte Ausführungsform der Klammer mit einem Offenhalteelement und sich in Offenstellung befindlichen Klammerelementen;

Fig. 10

in gleicher Darstellung wie Fig. 9 die dort gezeigte Klammer mit in Schliessstellung verbrachten Klammerelementen;

Fig. 11

die in den Fig. 9 und 10 gezeigte Klammer mit einer Steuereinrichtung zum Betätigen der Klammerelemente und des Offenhalteelements;

Fig. 12

in Seitenansicht und teilweise geschnitten die Klammer und Steuereinrichtung nach Fig. 11; und

Fig. 13

in perspektivischer Darstellung mehrere Klammern mit einem Offenhalteelement, das auch zum Öffnen der gehaltenen Gegenstände dient.

The present invention will be explained in more detail with reference to embodiments illustrated in the drawings. It shows purely schematically:

Fig. 1

in a perspective view of an inventive clip with two clip elements and an open-holding element before the acquisition of a multi-part, open sheet-like object, and a feeding device;

Fig. 2

in the same representation as Figure 1, the clip with located in the open position clamping elements during retraction of the hold-open element in the open sheet-like object.

Fig. 3

in the same representation as Figs. 1 and 2, the clip with in the closed position holding the object clamp elements and the between two parts of the object arranged hold-open element;

Fig. 4

in the same representation as Figures 1 to 3, the clip with the object holding the clip elements and with the further opening of the held object rotated by about 90 ° in an expanded position hold-open element.

Figure 5

in view of several, each holding a sheet-like object brackets with an open-holding element between each two parts of the object in question, wherein the brackets are located in a buffer section of a transport device;

Fig. 6

in the same representation as Figure 5 shows two holding an object brackets with in spread position twisted hold-open element.

Fig. 7

in view of another embodiment of a clamp with hold-open element in the open position of the clamp elements;

Fig. 8

in the same representation as Figure 7, the clip shown there in the closed position of the clip elements.

Fig. 9

a third embodiment of the clip with an open-holding element and located in the open position clamping elements;

Fig. 10

in the same representation as Figure 9, the clip shown there with spent in the closed position clamp elements.

Fig. 11

the bracket shown in Figures 9 and 10 with a control device for actuating the clamping elements and the hold-open element;

Fig. 12

in side view and partially cut the clip and control device of FIG. 11; and

Fig. 13

in perspective view several brackets with an open-holding element, which also serves to open the held objects.

The device shown in FIGS. 1 to 4 has a plurality of brackets 12, which are arranged one behind the other and are driven circumferentially along a path of movement 10, wherein only one of the brackets 12 is shown in each of these figures. The bracket 12 has two pivotable about an axis 16, cooperating clip elements 14 which are arranged by means of a control device 17 from an open position 18 in which the two clip elements 14 are arranged relative to each other V-shaped (see FIGS. 1 and 2) in a Closing position 18 'are convertible (Figures 3 and 4), in which the clamping elements 14 are intended to hold an object 70 arranged between them. The article is a folded printed product, but it can also be different type of two-part or multi-part flexible sheet-like objects. For the purposes of the present invention, a folded sheet has two parts which are joined together at the seam.

The clamp 12 further comprises an open-holding element 20 which is formed like a sword and is rotatable about its longitudinal axis 22, which is perpendicular to the axis 16 and in one of the closing position 18 'located in the clamping elements 14 defined clamping plane 24. Seen in the direction of the longitudinal axis 22, the free end 26 of the hold-open element 20 is located approximately at the free end of the closed position 18 'spent clamp elements 14. The sword-like hold-open element 20 is disposed at the end of a coaxially to the longitudinal axis 22 arranged shaft 28 which a bearing body 30 goes through and on this is rotatably mounted about the longitudinal axis 22. With respect to the bearing body 30, a control lever 32 is seated on the shaft 28 on the side opposite the hold-open element 20, at the free end of which a control roller 34 is freely rotatably mounted. This is intended to cooperate with a control element 36 shown in FIG. 4 with an arrow, for example a stationary control link, for rotating the hold-open element 20. 1 to 3, the sword-like hold-open element is in the open position 38, in which the longer extension of the cross-section extends in or parallel to the bracket plane 24. 4, the hold-open element 20 is shown in spread position 38 ', in which said extension extends at least approximately at right angles to the bracket plane 24.

The bearing body 30 is fixed to the end face of a guide body 40, which in turn is fastened on a side facing away from the bearing body 30 on a carriage 42. On the guide body 40, the two clamping elements 14 are arranged. In the present case, the two clip elements 40 are made from a common, one-piece bent spring steel sheet, which is fastened to the guide body 40 in the region of the bend, ie in the connection region of the two approximately flat legs. The two legs of the steel sheet are recessed from the free end, so that each leg has two fingers 44 forming a clamping element 14. On the outer side of each clamping element 14, a circular-cylindrical clamping body 46 is arranged, which runs parallel to the axis 16 and is secured to two rigid guide rods 48. These run parallel to the longitudinal axis 22, pass through the guide body 40 and are mounted on this displaceable in the longitudinal direction. On the side facing away from the clamping bodies 46 of the guide body 40, each guide rod 48 is surrounded by a compression spring 50, on the one hand on the guide body 40 and on the other hand a common all guide rods 48 common actuator plate 52 is supported.

In the open position 18 of the clamping elements 14, the clamping body 46 are held by the compression springs 50 on the guide body 40 in abutment. By means of a control member 54, such as a gate, a cylinder piston unit or the like, the clamping body 46 in the direction of the guide rods 48 away from the guide body 40 in the direction of the free end of the clamp members 14 are movable. In this case, the clamping body 46 slide along the outer side of the clamping elements 14 and pivot them in the closed position 18 '. At a distance from the guide body 40, the clamping elements 14 have latching depressions 56 into which the clamping bodies 46 come to rest when the clamp 12 is closed and are kept so stable due to the reaction force of the clamp elements 14 that they are released by the control member 54 Actuator plate 52 are held against the force of the compression springs 50 (Fig. 4).

For transferring the clamping elements 14 from the closed position 18 'back to the open position 18, the actuating plate 52 is retracted by means of another control member against the direction of arrow shown in FIG. 1, so that the clamping body 46 move out of the locking recess 56 and then through the Force of the compression springs 50 are brought into contact with the guide body 40. The clamp body 46 thereby release the clamp elements 14, which move as a result of the self-suspension according to the position of the clamp body 46 in the open position 18. Of course, it is conceivable to mount the clamp elements 14 rotatably on an axis and to bias by means of a spring in the open position.

The carriage 42 is mounted on two guide rails 58 which extend parallel to the longitudinal axis 22 and the guide rods 48 and are attached to a carrier 60 arranged on a support plate 58 '. For example, the carrier 60 may be attached to a carrier wheel, to a pulling member, or to a carriage or carriage guided in rails.

The device shown in FIGS. 1 to 4 further comprises a feeding device 62, at the downstream end 64 seen in the feeding direction Z, the movement path 10 of the clip 12 extends at right angles to the feed direction Z over. The feeder 62 has a support plate 66 slightly inclined from the vertical and a bottom member 68. Flexible, flat objects 70, folded in the present case multi-page printed products, are conveyed to the support plate 66 fitting in imbricated formation S, wherein the respective leading object 70 rests on the trailing. A dot-dash line indicated, in the feed direction Z circumferentially driven conveyor belt 72 transports the imbricated formation S in the feed direction Z to the downstream end 64 of the support plate 66 back. This has a recess extending from this end 64, which makes it possible to access the clamp 12 on the foremost object 70 of the imbricated formation S, respectively.

On the bottom element 68, spaced apart from the support plate 66, a guide strip 74 extending in the feed direction Z is fastened, which together with the support plate 66 forms a guide groove for the folded edge 66 of the objects 70.

As can be seen in particular from FIGS. 1 to 3, the objects 70 are folded off-center, so that the part 78 of the objects 70 facing the support plate 66 has a so-called prefold 80 protruding from the other part 78 '.

At the end 64 of the support plate 66 there is an opening device 82, which is intended to lift the part 78 'from the part 78 of the respective article 70 at its leading edge 84 in the feed direction Z from each other. For this purpose, the opening device 82 has a stop 86 and a retaining rod 88 protruding therefrom against the feed direction Z. This is bent in its free end region and forms together with the support plate 66 a narrowing guide gap for the prefold 80th

The embodiment of the clip according to the invention shown in FIGS. 1 to 4 functions as follows. In Fig. 1, a clip 12 is in takeover position at the downstream end 64 of the feeder 62. The clip elements 14 are in the open position 18 and the hold-open element 20 in the open position 38. The carriage 42 with the attached bracket 12 is located on the of the Feeder 62 remote end of the guide rails 58. The Vorfalz 80 of the support plate 66 facing part 78 of the article 70 is inserted between the support plate 66 and the retaining rod 88 and the leading edge 84 of this part 78 abuts against the stop 86. Due to the further promotion of the objects 70 in the feed direction Z, the leading edge 84 and an adjoining portion of the part 78 is bent away in the direction of the support plate 66, whereby the other part 78 'from the part 78 stands out.

As a result, as shown in FIG. 2, by means of the control member 54, the clamp 12 is moved along the guide rails 58 toward the feeder 62, thereby causing the clamp member 14 to move the respective article 70 from the leading one Edge 84 ago fro and on the other hand, the hold-open element 20 between the lifted-off parts 78, 78 ' of the article 70. This movement counter to the feed direction Z takes place until the carriage 42 on the corresponding support plate 58 ', on which the guide rails 58 are fixed, comes into abutment.

Upon further movement of the actuator plate 52 by means of the control member 54, as shown in FIG. 3, the clamp elements 14 are now transferred into the closed position 18 ', whereby they grasp the object 70. In this case, on the side of the clamping elements 14 facing away from the fold edge 76-outside the effective range of these-the two parts 78 and 78 'of the object 70 are kept open by means of the hold-open element 20 engaging therebetween.

While the staple 12 is being moved along the trajectory 10 from the feeder 62, on the one hand the prefold 80 is drawn out of the area between the retention bar 88 and the support plate 66 and on the other hand by turning the hold open element 20 about its longitudinal axis 22 by means of the control 36 Parts 78, 78 'of the article 70 further spread apart and thereby the object 70 further opened.

The clamp 12 together with the hold-open element 20 can be driven continuously along the movement path 10. In this case, the movement of the clamps 12 and the supplied objects 70 is matched to one another such that each clamp 12 detects and transports an object 70.

Fig. 5 shows three brackets 12 with associated hold-open element 20, which are located in a buffer path 90 of a transport device. This buffer section 90 is arranged in a section of the movement path 10 arranged downstream of the feed device 62. Each of these brackets 12 holds an article 70 between its parts 78, 78 ' In open position 38 located open-holding element 20 engages. In this case, the rotation of the hold-open element 20 explained in connection with FIG. 4 has not yet occurred in the spread position 38 ', so that the clamps 12 together with the objects 70 require minimal space and can be arranged abutting one another in the buffer path 90.

From the buffer section 90, the brackets 12 can be moved out by increasing the mutual distance, which allows the rotation of the hold-open element 20 in the spread position 38 'and the associated further opening of the objects 70, as shown in FIG.

FIGS. 7 and 8 show a further embodiment of a clamp 12 with associated hold-open element 20 according to the present invention. The clamping elements 14 are rod-shaped and parallel to each other. The hold-open element 20 is formed by two hold-open rods 20 'which run parallel to the clamp elements 14. Depending on a clamp member 14 and an open-holding rod 20 'are attached to the two ends of a lever 92, wherein the two levers are parallel axis mounted freely rotatably on a support member, not shown. Each of these levers 92 is connected to a gear 94, these gears meshing with each other for opposite rotation of the lever 92. In rest position 96, the two hold-open rods 20 'bear against one another and the clamp elements 14 are in a spaced open position 18.

7 further shows an article 70 which has been opened by means of an opening device 82, wherein the two holding-open bars 20 'between the two parts 78, 78' of the article 70 and the two clip elements 14 are arranged outside the latter by relative displacement of the clip 12 and the article 70. By opposing rotation of the two levers 92, the clip elements 14 toward each other in the closed position 18 ', clamping the object 70 therebetween, as shown in FIG. 8. Simultaneously with the movement of the staple elements 14, the hold-open rods 20' are moved from the inoperative position 96 into a spread position 38 ', thereby further guiding the two portions 78, 78' moved away from each other and thus the object 70 is opened further. The rotation of the gears 94 can be done by well-known control means.

9 and 10 show one of FIGS. 7 and 8 very similar embodiment of the inventive clip 12 with associated hold-open element 20. Also in this embodiment, each an open-holding rod 20 'and a rod-like trained clamping element 14 are attached to the two parallel axis levers 92. The levers 92 are rotatably connected to one gear 94, the gears 94 now mesh with a rack 98 arranged between them. By translational movement of the rack 98, the clamp elements 14 are moved from the open position 18 into the closed position 18 'and the same time the hold-open rods 20' from the rest position 96 in the spread position 38 'and vice versa. This embodiment makes it possible to actuate the clamp 12 and the hold-open element 20 by means of fixed links, wherein the clamp 12 is moved along these scenes, as will be explained with reference to FIGS. 11 and 12.

11 and 12 show a carriage 42 on which a bearing body 30 is integrally formed. This is penetrated by two parallel-axis shafts 100, on which on the one hand each a gear 94 and on the other hand each a lever 92 with the clamping elements 14 and hold-open rods 20 'rotatably seated. The double rack 98 is guided on the one hand in a guide passage 102 and on the other hand with its shaft-like extension 104 in a further guide passage 102 'translationally movable.

The extension 104 is encompassed by a compression spring 106, which is supported on the one hand on the rack 98 and on the other hand on the bearing body 30. From the extension 104 opposite end, the rack has a blind hole in which a support shaft 108 is slidably guided, at the free end of a control roller 110 is freely rotatably mounted. A further compression spring 106 'acts between the rack 98 and the support shaft 108. The force of the further compression spring 106' is in any case greater than the force of the compression spring 106. The latter is intended, the clamping elements 14 of the closed position 18 'in the open position 18, while the further compression spring 106 'serves to accommodate the thickness of different objects 70 during the interaction of the control roller 110 with a control link 112 - in the closed position 18' of the clamping elements 14.

The carriage 42 is slidably mounted on a cross-sectionally C-shaped carrier 60 in the longitudinal direction of the clamping elements 14 and hold-open rods 20 '. The carrier 60 is attached to a carrier wheel 114 which is driven in rotation about its axis. On the carrier wheel can be uniformly distributed more carriers 60, each with a clamp 12 may be arranged.

On the carriage 42, a further control roller 110 'is mounted, which cooperates with a stationary Verschiebekulisse 112'. By means of the sliding link 112 ', the clip is moved relative to the carrier 60 in a manner analogous to that of FIGS. 1 to 4.

The operation of the device according to FIGS. 11 and 12 is as follows. The clamp 12 is driven continuously along the circular trajectory 10 in the arrow direction. In the feeding device (cf. FIGS. 1 to 4), the clip 12 is moved toward the feeding device by means of the sliding link 112 'in order to include an article 70 with clamping elements 14 in the open position 18. there As indicated in phantom in FIG. 12, the control roller 110 lies in the initial region of the control cam 112 and then comes to rest on further rotation of the carrier wheel 114. The control link 112 then causes a movement of the rack 98 against the force of the compression spring 106 in the direction upwards, whereby the clamp members 14 in the closed position 18 'and the hold-open rods 20' in spread position 38 'are moved. For the transport of the detected objects 70 along the movement path 10, the clamp 12 is held in the closed position by means of the control link 112 serving as a closing cam. For the delivery of the articles 70, the link 112 'has a path away from the path of movement 10, whereby the opening of the clip 12 can take place by means of the compression spring 106.

Fig. 13 shows in a perspective view obliquely from above the feeding device 62 shown in Figs. 1 to 4 with conveyed in flake formation S in the feeding direction Z objects 70. The feeder 62 has no opening device 82 in this example. Of four along the trajectory 10 consecutively arranged brackets 12, only the clip elements 14 are indicated. Each clip 12 is associated with a hold-open element 20 which is intended to pierce with its tip in advance between parts 78, 78 'of the article 70 and then keep these open to each other separately. In the example shown, for this purpose the movement of the hold-open element 20 in the clamp plane 24 is perpendicular to the longitudinal direction of the clamp elements 14. The penetration of the hold-open element 20 and the opening of the article 70 can be assisted by an air jet directed to the respective article 70.

13, the clamp elements 14 are in the open position 18 and the clamp 12 is moved counter to the feed direction Z by the arrow 54; at the same time, the articles 70 are transported in the feed direction Z. Subsequently, the clamping elements 14 are transferred to the closed position 18 ', as indicated by the clamp elements 14 of the adjacent bracket 12 and the respective arrows. The associated hold-open element 20 is then moved in the direction of the arrow against the edge opposite the fold edge 76, the so-called flower, after which the hold-open element 20 punctures between two adjacent parts 78, 78 'of the respective article 70, as shown by the third clamp 12 from the left , By further penetration of the hold-open element 20 into the article 70 and possibly the rotation of the hold-open element 20, the parts 78, 78 'are spread further apart. The hold-open element 20 is suitable in this case for opening objects, in particular printed products, with and without prefold.

The embodiment shown in FIG. 13 is particularly suitable if the objects 70 are not necessarily to be centrally opened. This is the case, for example, if an insert or a sample is not to be inserted in the opened article 70. The opening of the articles can be done downstream of the feeder 62 at any time.

As opening device 82 for the objects 70 to be supplied, devices are also suitable, as described, for example, in the publications EP-A-0 574 741; US-A-5,441,245; EP-A-0 577 964; US-A-5,443,250; CH-A-641 113; CH-A-644,815 and US-A-4,420,146.

The clip 12 may also be designed such that the clip elements 14 instead of rotationally translationally toward each other and from each other can move away. It is also conceivable to arrange the hold-open element 20 so as to be pivotable about an axis perpendicular to its longitudinal direction. Of course, the feeding device may be formed differently in a generally known manner.

It is conceivable that the path of movement of the clamps 12 from the downstream end 64 of the feed device 62 in the feed direction Z does not run at a right angle but obliquely past the feed direction Z.

Claims (6)

1. Apparatus for transporting flexible, sheet-like articles with two or more parts, having a plurality of clamps (12) which are arranged one behind the other, are moved along a movement path (10) and each have two interacting clamp elements (14) which can be moved relative to one another from an open position (18) into a closed position (18'), are intended for retaining an article (70) and have a holding-open element (20) which is intended for engaging between two parts (78, 78') of the article (70) and, when the clamp elements (14) are located in the closed position (18'), for keeping these parts separate from one another in a region outside the clamp elements (14), characterized by devices for actuating the clamp elements (14) and the holding-open element (20), with the result that the clamp elements (14) are moved into the closed position (18') when the holding-open element (20) is located between the two parts (78, 78') of the article (70), and in that, when the clamp elements (14) are located in the closed position (18'), the holding-open element (20) is moved out of a holding-open position (38) into a spreading position (38') in order to spread the two parts (78, 78') of the article (70) further apart from one another and thus to open the article further.
2. Apparatus according to Claim 1, characterized in that a buffer-storage section (90) is arranged in a portion of the movement path (10) and the holding-open elements (20) of the clamps (12) which are located in the buffer-storage section (90), and retain an article (70), are located in the holding-open position (38).
3. Apparatus according to Claim 1 or 2, characterized in that the clamp elements (14) and the holding-open element (20) of each clamp. (12) are arranged on a common carrying element (60) which is driven in circulation along a movement path (10).
4. Apparatus according to one of Claims 1 to 3, characterized in that the holding-open element (20) is of tongue-like design and is mounted such that it can be rotated about its longitudinal axis (22), which is located at least more or less in a clamp plane (24) defined by the clamp elements (14) in the closed position (18').
5. Apparatus according to Claim 4, characterized in that the clamp elements (14) can be pivoted about an axis (16) which runs at least more or less at right angles to the longitudinal axis (22) of the holding-open element (20).
6. Apparatus according to one of Claims 1 to 5, characterized in that articles (70) which have a fold (76) are retained by the clamps (12) at an edge (84) adjoining the fold (76).

Images