WO2017178437A1

WO2017178437A1 - Gripping member, gripper bar and machine for processing elements in sheet form

Info

Publication number: WO2017178437A1
Application number: PCT/EP2017/058570
Authority: WO
Inventors: Jean-Luc Gillieron; Jean-François Pollien; Arnaud RAPIN
Original assignee: Bobst Mex Sa
Priority date: 2016-04-12
Filing date: 2017-04-10
Publication date: 2017-10-19

Abstract

The invention concerns a gripping member (5) for a gripper bar (2) of a machine (1; 1') for processing elements in sheet form, the gripper bar (2) comprising a transverse bar (3) and an opening pin (4), the gripping member (5) comprising: - a gripper finger (8) configured to be attached to the opening pin (4), - a counter gripper (9) configured to be attached to the transverse bar (3), - the gripper finger (8) being movable relative to the counter gripper (9) between a closed position and an open position by rotating the gripper finger (8), characterised in that the gripping member (5) comprises a push member (11) interposed between the gripper finger (8) and the counter gripper (9), the push member (11) comprising an elastic member (10) and at least one pusher element (16) elastically biased by the elastic member (10) to force the gripper finger (8) into the closed position. The present invention also concerns a gripper bar provided with a plurality of gripping members and a machine for processing elements in sheet form, comprising a plurality of gripper bars.

Description

GRIPPER, PLIERS BAR, AND ELEMENTS PROCESSING MACHINE

FORM OF SHEETS

The present invention relates to a gripping member for a sheet-like element processing machine gripper bar. The present invention also relates to a gripper bar provided with a plurality of gripping members and a sheet-like processing machine comprising a plurality of gripper bars.

A sheet-like processing machine, for example sheets of paper or cardboard for the manufacture of packaging, comprises a succession of workstations for effecting a transformation of the sheets, in particular by means of a press turntables. This type of machines being automated, means of transport are provided to bring each sheet successively in each of the workstations. In practice, it is usually a series of cross bars with clamps. These transverse bars, commonly called gripper bars, each in turn take a sheet at its front edge, before pulling successively in different workstations of the machine. The ends of the clip bars are each connected respectively to a side chain forming a loop, commonly referred to as a chain train. Through a movement transmitted to the chain trains, the set of gripper bars move from a stopped position, accelerate, reach a maximum speed, decelerate, then stop, thus describing an acceleration and speed cycle. corresponding to moving a sheet from one workstation to the next workstation. Each station performs its work in synchronism with this cycle, which is commonly called a machine cycle.

The search for an increase in the rate of production of the machine requires that successive translations between the workstations are performed at higher speeds and in a shorter and shorter cycle time.

To ensure sufficient gripping of the sheet-shaped element by small clamps mounted along the rear edge of the bar, the rear springs closing the clamps are short and strong. These springs arranged almost vertically ensure the closure of the clamps, the clamps opening by rotational drive of an opening axis of the clamp bar against the action of the springs.

The manufacturers wish to increase the maximum opening of the clamps in order to avoid machine stops caused by the tiling of thick sheets. This evolution of the clamps, however, must respect the constraints of weight and positioning of the axis opening and nose pliers and not to increase the height of the clamp bars that are sought to limit that of the chain trains.

Manufacturers also want to increase the clamping force in order to increase the production rate and guarantee the high-speed sheet transport while remaining compatible with the constraints of weight, size and positioning of the opening shaft and tongs of tongs.

One of the aims of the present invention is to provide a gripping member that can have a greater pinching force and / or a larger opening while respecting the aforementioned constraints.

For this purpose, the subject of the present invention is a gripping member for a sheet-like element processing machine gripper bar, the gripper bar comprising a transverse bar and an opening axis, the gripping member. comprising:

a clamp finger configured to be fixed to the opening axis,

a counter-clamp configured to be fixed to the crossbar,

the gripper finger being movable relative to the counter-gripper between a closed position and an open position by rotation of the gripper finger,

characterized in that the gripping member comprises a push member interposed between the gripper finger and the counter-gripper, the push member comprising an elastic member and at least one push member resiliently biased by the elastic member to constrain the finger clamp in the closed position.

The use of a pusher member, which is therefore not fixed to the gripping member, allows a slight movement of the gripper finger relative to the elastic member instead of a rigid attachment by riveting as in prior art. This avoids the exercise of too strong constraints at the level of the links with the elastic members, which tend to deform them. In addition, elastic members which are not fixed irreversibly to the gripper fingers but which are removably mounted, allow to easily change the gripping members when necessary.

According to one or more characteristics of the gripping member, taken alone or in combination,

the pusher element comprises a rotary roller,

the pusher element comprises a friction element,

- The pusher member comprises a base interposed between a second end of the elastic member and the pusher member, a first end of the elastic member. being in support against the counter-gripper,

the pusher element comprises a rotary roller and the base comprises a first shoe comprising a first bearing receiving a first end of the roller and a second shoe distinct from the first shoe and comprising a second bearing receiving a second end of the roller,

the pusher element comprises a friction element, the base and the friction element being made in one piece,

the pusher element is carried by a base of the pusher member,

the pusher element is urged in abutment against an end portion of the gripper finger,

the gripper finger is formed of a plate having:

a first wing forming a flat end of a nipping zone,

a second wing inclined with respect to the first wing, the second wing being configured to be fixed to the opening axis, and

a rectified end portion configured to cooperate with the pusher element,

the pusher element is carried by the gripper finger and is biased against the base,

the pusher member comprises a first axial guide element configured to guide the axial displacement of the elastic member,

the first axial guiding element comprises a cylindrical portion whose diameter is complementary to the internal diameter of a cylindrical elastic member to guide its axial displacement,

the counter-gripper comprises a second axial guide element configured to guide the axial displacement of the elastic member, the second axial guide element being configured to cooperate with the first axial guide element, the axial guide elements are telescopic,

the first axial guiding element is carried by the base,

the pusher element is made of synthetic material,

the elastic member comprises two springs arranged in parallel.

The subject of the invention is also a clip bar for a sheet-like processing machine comprising a transverse bar and an opening axis. ends of the gripper bars being each intended to be connected to a respective chain train of the processing machine characterized in that the gripper bar further comprises at least two gripping members as defined above, the gripper fingers being fixed at the opening axis and against-grippers being fixed to the crossbar, the pivoting of the opening axis causing the pivoting of the gripper fingers towards the open position against the action of the elastic members .

The opening of all the gripping members can thus be performed simultaneously and simply by driving in rotation of the opening axis.

The clip bar may comprise at least one lateral rotational driving element arranged at one end of the opening axis to cause the pivoting of the opening axis to the open position of the gripping members. The lateral drive member is configured to be rotated by means for actuating a work station of the processing machine to the passage of the gripper bar in the work station.

The lateral rotational driving element causing the pivoting of the opening axis against the elastic members, exerts a permanent force to keep the gripper fingers in the open position. Off lateral actuation, the clamp bar has only a stable position of closure. The clip bar is considered monostable. The resilient members may be at least partially received in the crossbar. For example, more precisely, the counter-grippers and resilient members may be partially received in the crossbar and emerge through windows of the crossbar and the gripper fingers may be arranged outside the crossbar.

With this arrangement, one can increase the bulk of the elastic members.

For example, the length of the elastic members may be lengthened without the second ends thereof exceeding the height of the transverse bar, in particular by positioning the resilient members at an angle to the vertical. Longer elastic members can thus be used to obtain the desired opening stroke while remaining compatible with the available space. By way of example, the axial length of an elastic member can thus be increased by more than 30% and the clamping force by more than 70% compared to devices of the state of the art.

The elastic members are for example helical springs whose direction axial is at an angle to the vertical which is greater than 30 °, such as greater than 50 °, such as between 50 ° and 80 °.

Another subject of the invention is a sheet-like processing machine comprising a plurality of workstations and a transport device for transporting each sheet successively in different workstations, the transport device comprising two transmission trains. chains, the processing machine being characterized in that the transport device comprises a plurality of gripper bars as previously described, configured to pinch the sheets by their front edges, the ends of the gripper bars each being connected to a gripper bar. respective chain train of the processing machine so that the chain trains are arranged laterally on each side of the clamp bars.

The processing machine comprises, for example, at least one actuating means arranged in a work station, the actuating means being configured to cooperate with a respective lateral driving element in rotation of the gripper bar to cause the pivoting of the axis of opening to the open position of the gripping members to the passage of the clamp bar in the work station.

SUMMARY DESCRIPTION OF THE DRAWINGS

Other advantages and characteristics will appear on reading the description of the invention, as well as on the appended figures which represent a non-limiting exemplary embodiment of the invention and in which:

FIG. 1 very schematically illustrates an example of a machine for processing sheet-shaped elements.

Figure 2 shows a perspective view of a clip bar.

Figure 3a shows a longitudinal sectional view of a first example of clamp bar with grippers in the closed position.

Figure 3b shows a view similar to Figure 3a with grippers in the open position.

FIG. 4a shows a longitudinal sectional view of a second example of a gripper bar with gripping members in the closed position. Figure 4b shows a view similar to Figure 4a with grippers in the open position.

Figure 5 shows a longitudinal sectional view of a third example of a gripper bar with grippers in the closed position.

Figure 6 shows a longitudinal sectional view of a fourth example of a gripper bar with gripping members in the closed position.

In these figures, the identical elements bear the same reference numbers. The following achievements are examples. Although the description refers to one or more embodiments, this does not necessarily mean that each reference relates to the same embodiment, or that the features apply only to a single embodiment. Simple features of different embodiments may also be combined or interchanged to provide other embodiments.

The longitudinal, vertical and transverse directions indicated in FIG. 2 are designated by the trihedron (L, V, T). The transverse direction T is the direction perpendicular to the longitudinal direction of movement of a sheet, as illustrated by the arrow D in FIGS. 1 and 2. The horizontal plane corresponds to the plane (L, T).

The terms upstream and downstream are defined with reference to the longitudinal direction of movement of the sheets D. These elements move from upstream to downstream, generally following the longitudinal main axis of the machine.

The terms "flat elements" and "sheets" will be considered equivalent, and will include both corrugated and cardboard components, paper or any other material commonly used in the packaging industry. It is understood that throughout this text, the terms "sheet" or "sheet element" or "sheet-shaped element" refer very generally to any sheet-like printing medium such as, for example , sheets of cardboard, paper, plastic, etc.

Fig. 1 shows an example of processing machine 1 for sheet processing. This processing machine 1 is conventionally composed of several workstations which are juxtaposed but interdependent one by one to form a unitary unit. There is thus an introduction station 100, a margin table 200, a transformation station 300 for cutting sheets, such as comprising a platen press 301, a waste ejection station 400 and a receiving station poses 500 where the Transformed leaves are reconditioned in piles and where the waste of cut leaves is evacuated.

The transformation operation of each sheet takes place in the transformation station 300, for example between a fixed plate and a lower movable plate of the press 301 for cutting the sheets according to a matrix corresponding to the developed form which is wishes to obtain, for example to obtain a plurality of boxes of a given form. The movable platen rises and lowers successively once during each machine cycle.

A transport device 70 is also provided to move each sheet individually from the output of the margin table 200 to the receiving station 500, through the processing station 300 per press.

The transport device 70 comprises a plurality of clamp bars 2, that is to say at least two clamp bars 2, such as between two and twenty clamp bars 2, such as eight in the example, which each come in turn seize a sheet at its front edge, before pulling successively in the various stations of the stations 300, 400, 500 of the machine 1.

The ends of the clamp bars 2 are each connected respectively to a side chain forming a loop, commonly called a chain train 80. Two chain trains 80 are thus arranged laterally on each side of the clamp bars 2.

With a movement transmitted to the chain trains 80, the set of clamp bars 2 will start from a stopped position, accelerate, reach a maximum speed, decelerate, then stop, thus describing a cycle corresponding to the movement of a sheet from a workstation to the next workstation. The chain trains 80 move and stop periodically so that during each movement, all the clamp bars 2 are moved from one station to the adjacent downstream work station. Each station performs its work in synchronism with this cycle, which is commonly called a machine cycle.

The number and nature of the treatment stations in a processing machine 1 may vary depending on the nature and complexity of the operations to be performed on the sheets. In the context of the invention, the concept of processing machine thus covers a very large number of embodiments because of the modular structure of these sets. Depending on the number, the nature and the arrangement of the workstations used, it is indeed possible to obtain a multitude of different processing machines. In addition, there are other types of workstations than those mentioned, such as embossing, crushing or such as punching tape loading stations for stamping machine or hot foil stamping machine (English). Finally, it is understood that the same processing machine may very well be equipped with several stations of the same type.

Figure 2 shows a bar of pliers 2 in more detail.

The clamp bar 2 comprises a transverse bar 3, an opening axis 4, a plurality of gripping members 5, that is to say at least two gripping members 5, such as between two and twenty bodies 5, as nine in the example, and two attachment devices 6 located at each end of the crossbar 3 to connect it to the side chain trains 80, the chains being connected upstream and downstream of the clamp bar 2 on a respective axis of the fastening devices 6.

The transverse bar 3 extends in the transverse direction T, perpendicular to the longitudinal direction of movement of the sheet-shaped elements D. The crossbar 3 is for example made of aluminum, magnesium or composite material.

The crossbar 3 has a substantially rectangular longitudinal section. The rear edge of the cross bar 3 (or "upstream" edge with respect to the longitudinal direction of movement of the sheets that move from upstream to downstream) is pierced with windows 7 at regular intervals.

The crossbar 3 may be hollow. It is for example made by a profile. In another example, the transverse bar is solid and has a plurality of open cavities on the windows 7.

The opening axis 4 allows the simultaneous opening of all the gripping members 5. It extends along the axis of the transverse bar 3, upstream side. This is for example a hollow aluminum tube.

As can be seen more clearly in FIGS. 3a and 3b, each gripping member 5 comprises a gripper finger 8, a counter-gripper 9 and a push member 11 interposed between the gripper finger 8 and the gripper clip 9.

The gripper finger 8 of each gripping member 5 is fixed to the opening axis 4, for example by means of at least one fastener 12, such as two screws, passing through front orifices formed in the gripper finger 8 and tappings of the opening axis 4, and in which the rods of the screws are received.

The counter-gripper 9 of each gripping member 5 is fixed to the transverse bar 3, for example by means of at least one fixing member, such as a screw, passing through an orifice formed in the bottom wall of the cross bar 3 and a tapping performed in correspondence in the counter-gripper 9.

The gripping area of the gripping member 5 for gripping the sheets is formed by a flat end 8a of the gripper finger 8 and a flat end 9a of the gripper 9. The flat end 8a of the gripper finger 8 is movable with respect to the flat end 9a of the counter-gripper 9 between a closed position (FIG. 3a) in which the gripping zone is closed and an open position (FIG. 3b) by rotation of the axis d 4, in which the flat end 8a of the gripper finger 8 has pivoted away from the flat end 9a of the counter-gripper 9.

The clamp bar 2 comprises for example at least one lateral rotational driving element 41 arranged at one end of the opening axis 4 of the clamp bar 2. The lateral rotational driving element 41 can thus being rotated by an actuating means of a work station 200, 500 of the processing machine 1 to the passage of the clamp bar 2 in the work station 200, 500 to cause the pivoting of the axis d opening 4 to the open position of the gripping members 5.

The clamp bar 2 comprises, for example, two lateral rotational drive elements 41, a lateral rotational drive element 41 being arranged at each end of the opening axis 4.

According to an exemplary embodiment, the lateral rotational drive element 41 comprises a pivoting lever. A pivoting lever is for example mounted at each end of the opening axis 4.

The lateral rotational driving element 41 may have a rotary roller 42 at an upstream end of the pivoting lever, making it possible to impart a rotational movement to the opening axis 4 from a working station of the machine 1 (FIG. Figure 2). Thus, when the gripper bar 2 arrives at the margin table 200 or the receiving station 500, a means of actuating the work station, such as a lever or a cam in the case of on-the-fly ejection, raises the rotary rollers 42 of the pivoting levers of the lateral rotating drive members 41 to turn the opening axis 4 so as to lift the gripper fingers 8 and simultaneously open all the gripping members 5.

In another example, a roller raises a lever mounted at the end of the opening axis 4 to rotate the opening axis 4.

The simultaneous opening of the gripping members 5 against elastic members 10 can thus be performed in a controlled, simple and automatic way to the passage of the clamp bar 2 in the work station 200, 500. The rotational drive of the opening axis 4 by at least one lateral drive element 41 furthermore makes it possible to have only one or two actuating means cooperating with a lateral driving element in rotation 41 respective for the simultaneous opening of all the gripping members 5. It is not necessary to provide an actuating means for each gripping member 5, which limits the number of parts of the gripper bar 2, and therefore costs and facilitates maintenance. Furthermore, the actuating means, which may be a lever, a roller or a cam, can be realized in a simple manner.

The pusher member 11 comprises an elastic member 10 and at least one pusher member

16.

The pusher element 16 is resiliently biased by the elastic member 10 to constrain the gripper finger 8 in the closed position.

The use of a pusher member 11, which is not attached to the gripping member 5, allows a slight displacement of the gripper finger 8 relative to the elastic member 10 instead of a rigid attachment by riveting as in the prior art. This avoids the exercise of excessive stresses at the connections with the elastic members 10, which tend to deform. This risk may be all the more important as the elastic members 10 are long. Also, this risk can be increased for elastic members 10 positioned at an angle. In addition, elastic members 10 which are not fixed irreversibly to the gripper fingers 8 but which are removably mounted, allows to easily change the gripping members 5 when necessary.

The pusher element 16 comprises for example a rotating roller. The rotating roller is rotatable about an axis parallel to the opening axis 4. A pusher element 16 made by a rotating roller allows a "rolling" contant between the pusher member 11 and the gripper finger 8 ( FIGS. 3a, 3b) or a "rolling" contact between the pusher element 16 and a base 170 of the pusher member 11 as will be seen below (FIGS. 4a, 4b). The use of rolling elements greatly reduces the friction and therefore limits the wear of the push elements 16.

The elastic member 10 comprises for example at least one compression spring, such as a coil spring. A first end of the elastic member 10 is in abutment against a base 9d of the counter-gripper 9. A second end of the elastic member 10 bears against a wall, for example flat and radial, of a base of the push member 11.

The elastic member 10 may comprise two springs that can be arranged in parallel, for example on either side of a central bridge of the counter-gripper 9 which ensures their centering. According to another example, the elastic member 10 comprises only one spring which can be arranged in central position.

The elastic members 10 may be at least partially received in the transverse bar 3. More precisely, the counter-grippers 9 and the elastic members 10 may be partially received in the transverse bar 3 and emerge through the windows 7 (FIGS. 3a, 3b, 4a, 4b), while the gripper fingers 8 are arranged outside the transverse bar 3. With this arrangement, it is possible to increase the bulk of the elastic members 10.

For example, the length of the elastic members 10 may be lengthened without the second ends thereof exceeding the height of the transverse bar 3, in particular by positioning the resilient members 10 at an angle to the vertical. Longer elastic members 10 can thus be used to obtain the desired opening stroke while remaining compatible with the available space. For example, the axial length of an elastic member 10 can be increased by more than 30% and the clamping force by more than 70%.

The elastic members 10 are, for example, helical springs whose axial direction forms an angle α with the vertical, the angle α being greater than 30 °, such that greater than 50 °, such that between 50 ° and 80 ° (FIG. 3a).

According to a first exemplary embodiment visible in FIGS. 3a and 3b, the pusher element 16 is biased in abutment against the gripper finger 8. The pivoting of the gripper finger 8 driven by the opening axis 4 thus allows the light weight moving the gripper finger 8 relative to the pusher member 11.

The pusher element 16 is for example carried by a base of the pusher member 11.

In the case of a rotary roller, the base comprises for example a first shoe 17 comprising a first bearing receiving a first end of the roller 16 and a second shoe 17, distinct from the first shoe 17, having a second bearing receiving a second end of Roller 16. The bearings are thus formed opposite the walls on which the elastic member 10 rests. Transversely extending cavities are formed in the shoes 17 upstream of the bearings, to receive a respective end of the roller 16 so that the roller is free to rotate on its bearings.

According to an exemplary embodiment shown in Figures 3a and 3b, the gripper finger 8 comprises a plate, such as a metal plate. The plate has two wings 8a, 8b inclined relative to each other. A first wing 8a forms the upper flat end 8a of the nipping zone.

The frontal orifices for the assembly of the fasteners 12 are provided in the second wing 8b. The gripper finger 8 further comprises an end portion 8c at the end of the second flange 8b, configured to cooperate with the pusher element 16. This end portion 8c is straightened towards the vertical direction V. Thus adjusted, the end portion 8c is normal to the axial direction of the inclined elastic member 10 while allowing the gripper finger 8 to have a low height not exceeding the height of the crossbar 3.

The gripper finger 8 may further comprise a central opening, formed in the center of the two wings 8a, 8b for the passage of the central bridge and a non-return stop 9c of the counter-gripper 9. The non-return stop 9c avoids the return of the sheet element in the gripping member 5 in the open position during the on-the-fly ejection of the waste sheet.

A clamp finger 8 of this type is simple to make.

Furthermore, it can be provided that the pusher member 11 comprises at least one first axial guide member 19, 20 configured to guide the axial displacement of the second end of the elastic member 10.

The first axial guide element 19, 20 is for example carried by the base. The first axial guide element 19, 20 extends for example from a wall of the shoe 17 opposite to that bearing the bearing in rolling contact with the pusher element 16. The first axial guide element 19, 20 is, for example, one piece with the shoe 17. The first axial guide member 19, 20 is not therefore fixed to the gripping member 5. This limits the mechanical stresses and the number of parts of the gripping member. 5.

The first axial guide member 19, 20 comprises for example a cylindrical portion 20 whose diameter is complementary to the internal diameter of a cylindrical elastic member 10, such as a helical spring, to guide its axial displacement.

In another example, the axial guide member 19 is configured to axially guide the elastic member 10 being disposed outside and around the latter. The axial guide member 19 can then be made in the form of a tube.

A first axial guide member 19, 20 may comprise a rod 19. In the example illustrated, each shoe 17 thus comprises a rod 19. Each rod 19 extends for example a cylindrical portion 20 of larger diameter. The cylindrical portions 20 project, for example, from the walls of the shoe 17 on which the second ends of the elastic member 10 rest. The rods 19 and the cylindrical portions 20 extend in the axial direction of the springs 10, to the inside of these. The counter-gripper 9 may also comprise at least one second axial guide element 9e configured to guide the axial displacement of the first end of the elastic member 10.

The counter-gripper 9 comprises, for example, two second axial guiding elements 9e, one for each elastic member 10.

Each axial guide element 9e comprises for example a tube fixed to the base 9d, the tube extending in the axial direction of the elastic members 10.

The second axial guiding element 9e can be configured to cooperate with a first axial guiding element 19. For example, axial guiding elements 9e, 19 are telescopic, such as telescopic tubes, the rod 19 of the first axial guiding element sliding in or out of the tube of the second axial guide member 9e.

The rod 19 of the first axial guide member can pass through the counter-gripper 9 at a hole in the base 9d, at least when the gripper finger 8 is in the open position. For example, the rods 19 of the first axial guiding elements pass through the counter-gripper 9 when the gripper finger 8 is in the closed position (FIG. 3a, 4a) as well as when the gripper finger 8 is in the open position ( Figure 3b, 4b). This facilitates the guidance of the telescopic elements.

With axial guiding elements 9e, 19, it avoids the deformation in the form of an arc of the compressed springs, in particular to allow the use of long and / or biased springs.

The counter-clamp 9 comprising the flat end 9a of the clamping zone, the central bridge, the non-return stopper 9c, the base 9d and the axial guide elements 9e can be made in one piece.

The central bridge has a generally rounded shape bearing on the opening axis 4. It connects the flat end 9a to the base 9d. The orifice in the bottom wall of the crossbar 3 for assembling the fastener is formed between the central bridge and the base 9d. The non-return stop 9c is formed by a vertical wall arranged between the central bridge and the flat end 9a. The flat end 9a is located in the horizontal extension of the bottom wall of the crossbar 3.

The counter-clamp 9 and / or the base and / or the pusher element 16 may be made of synthetic material, such as plastic such as PPS (polyphenylene sulphide), PET-C (polyethylene terephthalate) ) or POM (polyoxymethylene), it is possible to reduce the coefficients of friction between the moving parts. We will now describe the operation of the clamp bar 2 with reference to Figures 2, 3a and 3b, considering the initial position for which the gripping members 5 are in the closed position for transporting a sheet-shaped element in the processing machine 1.

When the gripper bar 2 arrives at the margin table 200 or the receiving station 500, the levers or cams of the machine 1 lift the rotary rollers 42 at the upstream end of the pivoting levers 41, rotating the machine. opening axis 4.

This pivoting of the opening axis 4 causes the lifting of the end portions 8c of the gripper fingers 8 against the action of the elastic members 10. The first axial guiding elements 19 slide in the second axial guide elements 9e, guiding the deformation in axial compression of the elastic members 10. The gripper fingers 8 move slightly with respect to the elastic members 10 during the compression of the elastic members 10, which makes it possible to avoid the clawing movement of the elastic members 10.

In the open position, the gripping members 5 may have a maximum opening of a height up to 20 millimeters for example, allowing the output / insertion of the sheet-shaped elements.

Figures 4A and 4B show a second embodiment.

This embodiment differs from the preceding in that the pusher element 16 is carried by the gripper finger 8 and is urged in abutment against a base 170 of the gripping member 5, itself bearing against the second end. of the elastic member 10.

The pivoting of the gripper finger 8 thus allows the gripper finger 8 to move relative to the elastic member 10.

The pusher element 16 is for example carried by the rectified end portion 8c of the gripper finger 8 to position the pusher element 16 in the axial direction of the inclined elastic member 10 while allowing the gripper finger 8 to present a low height not exceeding the height of the cross bar 3.

The base comprises, for example, two distinct shoes 17, each having a wall on which the elastic member 10 rests and an opposite planar or cylindrical surface against which the rotating roller is in "rolling" contact.

The first axial guide element 19, 20 extends for example from the wall of the shoe 17 on which the resilient member 10 rests, opposite the face in rolling contact with the pusher element 16. Figures 5 and 6 show two other embodiments.

In these embodiments, the pusher element 16 is a friction element.

The friction element 16 has for example a convex surface, for example cylindrical, to facilitate a displacement by rubbing contact. This is for example a non-rotating cylinder.

A pusher element 16 made by a rubbing element allows a contant "rubbing" between the pusher member 11 and the gripper finger 8 (FIG. 5) or a "rubbing" contact between the pusher element 16 and the base 170 (FIG. ).

The rubbing element is for example carried by a base of the gripping member 5 (Figure 5). The base 17 and the rubbing element are for example made in one piece.

The first axial guiding element 19, 20 extends for example from the wall of the base 17 opposite to that carrying the pusher element 16.

The friction element is for example carried by the gripper finger 8 and is urged in abutment against a base 170 of the gripping member 5, itself bearing against the second end of the elastic member 10 (FIG. 6). .

The gripper finger 8 and the friction element 16 are for example made in one piece.

The first axial guiding element 19, 20 extends for example from the wall of the base 170 opposite to that bearing the face in rubbing contact with the pusher element 16.

Claims

1. Gripping member (5) for a gripper bar (2) of a processing machine (1; 1 ') of sheet-like elements, the gripper bar (2) comprising a transverse bar (3) and an axle of opening (4), the gripping member (5) comprising:

- a gripper finger (8) configured to be fixed to the opening axis (4),

a counter-gripper (9) configured to be fixed to the transverse bar (3),

- the gripper finger (8) being movable relative to the counter-gripper (9) between a closed position and an open position by rotation of the gripper finger (8), characterized in that the gripping member (5) comprises a push member (11) interposed between the gripper finger (8) and the counter-gripper (9), the push member (11) comprising a resilient member (10) and at least one push member (16). ) resiliently biased by the elastic member (10) to constrain the gripper finger (8) in the closed position, the pusher member (16) having a rotating roller.

2. Gripping member (5) according to the preceding claim, characterized in that the pusher member (11) comprises a base (17; 170) interposed between a second end of the elastic member (10) and the pusher member. (16), a first end of the elastic member (10) bearing against the against-gripper (9).

3. Gripping member (5) according to the preceding claim, characterized in that the base comprises a first shoe (17) having a first bearing receiving a first end of the rotating roller and a second shoe (17) separate from the first shoe (17). ) and having a second bearing receiving a second end of the rotating roller.

4. gripping member (5) according to one of the preceding claims, characterized in that the pusher element (16) is urged against an end portion (8c) of the gripper finger (8).

5. gripping member (5) according to one of claims 2 or 3, characterized in that the pusher element (16) is carried by the gripper finger (8) and is urged in support against the base (170) .

6. Gripping member (5) according to one of the preceding claims, characterized in that the gripper finger (8) is formed of a plate having:

a first wing (8a) forming a flat end of a nipping zone,

a second wing (8b) inclined relative to the first wing (8a), the second wing (8b) being configured to be fixed to the opening axis (4), and

a rectified end portion (8c), configured to cooperate with the element pusher (16).

7. gripping member (5) according to one of the preceding claims, characterized in that the pusher member (11) comprises a first axial guide member (19, 20) configured to guide the axial displacement of the elastic member (10).

8. gripping member (5) according to the preceding claim, characterized in that the first axial guide member (20) comprises a cylindrical portion whose diameter is complementary to the internal diameter of a cylindrical elastic member (10) for guiding its axial displacement.

9. gripping member (5) according to one of claims 7 or 8, characterized in that the counter-gripper (9) comprises a second axial guide member (9e) configured to guide the axial displacement of the elastic member (10), the second axial guiding element (9e) being configured to cooperate with the first axial guiding element (19).

10. gripping member (5) according to the preceding claim, characterized in that the axial guide members (9e, 19) are telescopic.

1 1. Gripper (5) according to one of claims 7 to 10, taken with claim 2, characterized in that the first axial guide member (19, 20) is carried by the base (17; 170).

12. Gripping member (5) according to one of the preceding claims, characterized in that the pusher element (16) is made of synthetic material.

13. gripping member (5) according to one of the preceding claims, characterized in that the elastic member (10) comprises two springs (10) arranged in parallel.

14. A gripper bar (2) for a processing machine (1; 1 ') of sheet-shaped elements having a transverse bar (3) and an opening axis (4), the ends of the gripper bars ( 2) being each intended to be connected to a respective chain train (80) of the processing machine (1; 1 ') characterized in that it comprises at least two gripping members (5) according to one of the claims previous, the gripper fingers (8) being fixed to the opening axis (4) and the counter-grippers (9) being fixed to the transverse bar (3), the pivoting of the opening axis (4). ) causing the gripper fingers (8) to pivot towards the open position against the action of the elastic members (10).

15. Gripper bar (2) according to the preceding claim, characterized in that it comprises at least one lateral rotational driving element (41) arranged at one end of the opening axis (4) to drive the pivoting of the opening axis (4) towards the open position of the gripping members (5), the lateral rotating element (41) being configured to be rotated by an actuating means of a work station (200, 500) of the processing machine (1; 1 ') at the passage of the clamp bar (2) in the work station (200, 500).

16. Bar clamps (2) according to one of claims 14 or 15, characterized in that the resilient members (10) are at least partially received in the crossbar (3).

17. Bar clamps (2) according to the preceding claim, characterized in that the elastic members (10) are helical springs whose axial direction forms an angle (a) with the vertical, the angle (a) being greater than 30 °, such as greater than 50 °, such as between 50 ° and 80 °.

18. Sheet processing machine (1; 1 ') comprising a plurality of work stations (100, 200, 300, 400, 500) and a transport device (70) for conveying each sheet successively in different work stations (300, 400, 500), the transport device (70) comprising two chain trains (80) characterized in that the transport device (70) comprises a plurality of gripper bars (2) according to one of claims 14 to 17, configured to pinch the sheets by their front edges, the ends of the clip bars (2) being each connected to a respective string (80) of the processing machine (1; 1 ') so that the chain trains (80) are arranged laterally on each side of the clamp bars (2).

19. Processing machine (1; 1 ') according to the preceding claim, characterized in that it comprises at least one actuating means arranged in a work station (200, 500), the actuating means being configured for cooperate with a respective rotational lateral element (41) of the gripper bar (2) to cause the pivoting of the opening axis (4) to the open position of the gripping members (5) at passing the clamp bar (2) into the work station (200, 500).

20. A gripping member (5) for a gripper bar (2) of a processing machine (1; 1 ') of sheet-like elements, the gripper bar (2) comprising a transverse bar (3) and an axle opening (4), the gripping member (5) comprising:

- a gripper finger (8) configured to be fixed to the opening axis (4),

a counter-gripper (9) configured to be fixed to the transverse bar (3),

- the gripper finger (8) being movable relative to the counter-gripper (9) between a closed position and an open position by rotation of the gripper finger (8), characterized in that the gripping member (5) comprises a push member (11) interposed between the gripper finger (8) and the counter-gripper (9), the push member (11) comprising an elastic member (10) and at least one pusher element (16) resiliently biased by the elastic member (10) to constrain the gripper finger (8) in the closed position, the pusher member (11) comprising a base ( 17, 170) interposed between a second end of the elastic member (10) and the pusher member (16), a first end of the elastic member (10) bearing against the counter-gripper (9).

21. Gripping member (5) according to the preceding claim, characterized in that the pusher element (16) comprises a rotating roller or a rubbing element.

22. gripping member (5) according to claim 20, characterized in that the pusher element (16) comprises a rotary roller, the base having a first shoe (17) having a first bearing receiving a first end of the rotating roller and a second shoe (17) distinct from the first shoe (17) and comprising a second bearing receiving a second end of the rotating roller.

23. gripping member (5) according to claim 20, characterized in that the pusher element (16) comprises a rubbing element, the base (17; 170) and the rubbing element being made in one piece.

24. gripping member (5) according to one of claims 20 to 23, characterized in that the pusher element (16) is urged against an end portion (8c) of the gripper finger (8).

25. Gripping member (5) according to one of claims 20 to 23, characterized in that the pusher element (16) is carried by the gripper finger (8) and is biased against the base (170) .

Gripper (5) according to one of claims 20 to 25, characterized in that the gripper finger (8) is formed of a plate having:

a first wing (8a) forming a flat end of a pinching zone; a second wing (8b) inclined relative to the first wing (8a); the second wing (8b) inclined relative to the first wing (8a);

(8b) being configured to be attached to the opening axis (4), and

- A rectified end portion (8c), configured to cooperate with the pusher element (16).

27. gripping member (5) according to one of claims 20 to 26, characterized in that the pusher member (11) comprises a first axial guide member (19, 20) configured to guide the axial displacement of the elastic member (10).

28. gripping member (5) according to the preceding claim, characterized in that the first axial guide member (19, 20) comprises a cylindrical portion (20) whose diameter is complementary to the inner diameter of a cylindrical elastic member (10) to guide its axial displacement.

29. Gripping member (5) according to one of claims 27 or 28, characterized in that the counter-gripper (9) comprises a second axial guide member (9e) configured to guide the axial displacement of the elastic member. (10), the second axial guiding element (9e) being configured to cooperate with the first axial guiding element (19).

30. gripping member (5) according to the preceding claim, characterized in that the axial guide members (9e, 19) are telescopic.

31. Gripper (5) according to one of claims 27 to 30, characterized in that the first axial guide element (19, 20) is carried by the base (17; 170).

32. Gripping member (5) according to one of claims 20 to 31, characterized in that the pusher element (16) is made of synthetic material.

33. Gripping member (5) according to one of claims 20 to 32, characterized in that the elastic member (10) comprises two springs (10) arranged in parallel.

34. A gripper bar (2) for a processing machine (1; 1 ') of sheet-like elements, having a transverse bar (3) and an opening axis (4), the ends of the gripper bars ( 2) being each intended to be connected to a respective chain train (80) of the processing machine (1; 1 ') characterized in that it comprises at least two gripping members (5) according to one of the claims 20 to 33, the gripper fingers (8) being fixed to the opening axis (4) and the counter-grippers (9) being fixed to the transverse bar (3), the pivoting of the opening axis (4) causing the tongs (8) to pivot towards the open position against the action of the elastic members (10).

35. Gripper bar (2) according to the preceding claim, characterized in that it comprises at least one lateral rotational driving element (41) arranged at one end of the opening axis (4) to drive the pivoting of the opening axis (4) to the open position of the gripping members (5), the lateral rotating drive member (41) being configured to be rotated by an actuating means a work station (200, 500) of the processing machine (1; 1 ') at the passage of the clamp bar (2) in the work station (200, 500).

36. Gripper bar (2) according to one of claims 34 or 35, characterized in that the elastic members (10) are at least partially received in the crossbar (3).

37. Gripper bar (2) according to the preceding claim, characterized in that the elastic members (10) are helical springs whose axial direction forms an angle (a) with the vertical, the angle (a) being greater than 30 °, such that greater than 50 °, such that between 50 ° and 80 °.

38. A sheet-like processing machine (1; 1 ') comprising a plurality of work stations (100, 200, 300, 400, 500) and a transport device (70) for conveying each sheet successively in different work stations (300, 400, 500), the transport device (70) comprising two chain trains (80) characterized in that the transport device (70) comprises a plurality of gripper bars (2) according to one of claims 34 to 37, configured to pinch the sheets by their front edges, the ends of the clip bars (2) being each connected to a respective string (80) of the processing machine (1; 1 ') so that the chain trains (80) are arranged laterally on each side of the clamp bars (2).

39. Processing machine (1; 1 ') according to the preceding claim, characterized in that it comprises at least one actuating means arranged in a work station (200, 500), the actuating means being configured to cooperate with a respective rotational lateral element (41) of the gripper bar (2) to cause the pivoting of the opening axis (4) to the open position of the gripping members (5) at passing the clamp bar (2) into the work station (200, 500).

40. A gripper bar (2) for a processing machine (1; 1 ') of sheet-like elements, comprising a transverse bar (3) and an opening axis (4), the ends of the gripper bars ( 2) being each intended to be connected to a respective chain train (80) of the processing machine (1; 1 ') characterized in that it comprises at least two gripping members (5), each gripping member ( 5) comprising:

- a gripper finger (8),

- a counter-gripper (9), the gripper finger (8) being movable relative to the counter-gripper (9) between a closed position and an open position by rotation of the gripper finger (8),

- A pusher member (11) interposed between the gripper finger (8) and the counter-gripper (9), the pusher member (11) comprising a resilient member (10) and at least one pusher member (16) resiliently biased by the resilient member (10) to constrain the gripper finger (8) to the closed position, the gripper fingers (8) being attached to the opening axis (4) and the counter-grippers (9) being fixed to the crossbar (3), the pivoting of the opening axis (4) causing the pivoting fingers (8) to pivot towards the open position against the action of the elastic members (10).

41. Gripper bar (2) according to the preceding claim, characterized in that it comprises at least one lateral rotational driving element (41) arranged at one end of the opening axis (4) to cause the pivoting of the opening axis (4) towards the open position of the gripping members (5), the lateral rotational driving element (41) being configured to be rotated by an actuating means of a work station (200, 500) of the processing machine (1; 1 ') at the passage of the gripper bar (2) in the work station (200, 500).

42. Gripper bar (2) according to one of claims 40 or 41, characterized in that the resilient members (10) are at least partially received in the crossbar (3).

43. Gripper bar (2) according to the preceding claim, characterized in that the elastic members (10) are helical springs whose axial direction forms an angle (a) with the vertical, the angle (a) being greater than 30 °, such as greater than 50 °, such as between 50 ° and 80 °.

44. Gripper bar (2) according to one of claims 40 to 43, characterized in that the pusher element (16) comprises a rotating roller or a rubbing element.

45. Gripper bar (2) according to one of claims 40 to 44, characterized in that the push member (11) comprises a base (17; 170) interposed between a second end of the elastic member (10). and the pusher element (16), a first end of the elastic member (10) bearing against the counter-gripper (9).

46. Gripper bar (2) according to the preceding claim, characterized in that the pusher element (16) comprises a rotary roller, the base comprising a first shoe (17) having a first bearing receiving a first end of the roller (16). ) and a second shoe (17) separate from the first shoe (17) and having a second bearing receiving a second end of the roller (16).

47. Gripper bar (2) according to claim 45, characterized in that the pusher element (16) comprises a rubbing element, the base (17) and the rubbing element being made in one piece.

48. Gripper bar (2) according to one of claims 40 to 47, characterized in that the pusher element (16) is urged against an end portion (8c) of the gripper finger (8).

49. Gripper bar (2) according to one of claims 40 to 47, characterized in that the pusher element (16) is carried by the gripper finger (8) and is biased against the base (170). .

50. Gripper bar (2) according to one of claims 40 to 49, characterized in that the gripper finger (8) is formed of a plate having: a first wing (8a) forming a flat end of a nipping zone,

51. Gripper bar (2) according to one of claims 40 to 50, characterized in that the pusher member (11) comprises a first axial guide member (19, 20) configured to guide the axial displacement of the elastic member (10).

52. Gripper bar (2) according to the preceding claim, characterized in that the first axial guide element (19, 20) comprises a cylindrical portion (20) whose diameter is complementary to the internal diameter of an elastic member (10). ) cylindrical to guide its axial displacement.

53. Gripper bar (2) according to one of claims 51 or 52, characterized in that the counter-gripper (9) comprises a second axial guide element (9e) configured to guide the axial displacement of the elastic member. (10), the second axial guiding element (9e) being configured to cooperate with the first axial guiding element (19).

54. Gripper bar (2) according to the preceding claim, characterized in that the axial guide elements (9e, 19) are telescopic.

55. Gripper bar (2) according to one of claims 51 to 54, characterized in that the first axial guide member (19, 20) is carried by the base (17; 170).

56. Gripper bar (2) according to one of claims 40 to 55, characterized in that the pusher element (16) is made of synthetic material.

57. Gripper bar (2) according to one of claims 40 to 56, characterized in that the elastic member (10) comprises two springs (10) arranged in parallel

58. A sheet-like processing machine (1; 1 ') comprising a plurality of work stations (100, 200, 300, 400, 500) and a transport device (70) for conveying each sheet successively in different work stations (300, 400, 500), the transport device (70) comprising two chain trains (80) characterized in that the transport device (70) comprises a plurality of gripper bars (2) according to one of claims 40 to 57, configured to pinch the sheets by their front edges, the ends of the clip bars (2) being each connected to a respective string (80) of the processing machine (1; 1 ') so that the chain trains (80) are arranged laterally on each side of the clamp bars (2).

59. Processing machine (1; 1 ') according to the preceding claim, characterized in that it comprises at least one actuating means arranged in a work station (200, 500), the actuating means being configured to cooperate with a respective rotational lateral element (41) of the gripper bar (2) to cause the pivoting of the opening axis (4) to the open position of the gripping members (5) at passing the clamp bar (2) into the work station (200, 500).