EP1982937B1 - Transport device for folding-gluing machine - Google Patents

Abstract

The device has displacement slides (20), displacement screw (30) and driving shaft (40) that are arranged between longitudinal frames. Longitudinal side rails support an endless transport belt (70). The rails are mounted on the slides and shaft by a sliding connection and mounted with the screw by a helical connection. A driving shaft protection unit transversally connects the frames. The shaft is arranged between wings (9a, 9b) of a U-shaped profile (9) of the protection unit.

Description

Technical area

The present invention relates to a device for transporting plate elements of low specific mass, paper or cardboard, within a folder-gluer machine; machine commonly used in the packaging industry for making, for example, cardboard boxes.

State of the art

Traditionally, a folder-gluer machine comprises a series of modules and stations whose number varies according to the complexity of the manufacturing operations that requires the type of box chosen. Such machines generally consist of a feeder supplying the production of cut-out boxes from a stack, an alignment module, a breaker pre-crushing the first and third folds between 90 ° and 180 °, a module of folders with hooks which bend at 180 ° the front legs and the rear legs of the cut, a gluing station, a folder for folding the 2nd and 4th folds of the cut, a presser that compresses the 2nd and 4th folds and deposits the boxes in sheet, and finally a receiving module that receives the boxes while keeping them pressed to allow the glue to dry. The conveyance of the blanks from one station to another is carried out by means of belt conveyors which, by friction, grip the cuts between a lower conveyor and an upper conveyor. Traditionally, the lower conveyor is provided with lower belts and the upper carrier is provided with either upper belts or upper support rollers.

The lower conveyor comprises two or more longitudinal longitudinal members each supporting an endless conveyor belt guided by pulleys and rollers. Each spar is mounted laterally sliding through bearings along one or more slideways mounted fixed between two longitudinal frames. In order to adapt the lateral position of the longitudinal members according to the format of the cuts to be treated, the lateral displacement of each beam is ensured by one or more parallel screws mounted in rotation between the frames, the threaded portions of the screws being respectively engaged in transverse threaded orifices of the longitudinal members.

For each spar, the drive of the endless conveyor belt is provided by a drive shaft rotatably mounted between the frames and engaged in a pulley of the spar, called driving pulley. The drive shaft is connected by a drive train to an electric motor, so when the motor is running, the shaft is rotated.

Generally, the drive shaft is in the form of a metal bar of polygonal section, for example hexagonal, cooperating form with a transverse orifice formed in the axis of the drive pulley. Thus, when a spar moves laterally under the action of the adjusting screws, it slides along the slideways and along the drive shaft.

It will be noted that the power required to work and to cause the cuts in the machine depends on the width of the machine. As a result, the larger the machine, the greater the forces to be transmitted, which makes it necessary to increase the torsional resistance of the shaft, for example by increasing its section. Thus, the drive shaft should be designed only to withstand torsion since the weight of the rails is supported by the slides movement but in practice we see that machine operators do not hesitate to climb on the drive shaft to access certain parts of the machine. Therefore, to prevent the drive shaft from bending, it is also designed to support the weight of a man without bending, which increases the cost of manufacturing the tree.

In addition, for safety reasons, parts of the drive shaft exposed to the machine operator are engaged in sleeves. A sleeve is generally in the form of a volute spring whose end is secured to a frame and whose other end is secured to a spar, the lateral displacement of the spar causing the extension or compression of the spring . It is easy to understand that the presence of such a spring requires dimension the strut moving screws accordingly. Indeed, the greater the stiffness of the volute spring is important and the torque to exert on the screws to move the side members must be important, which also involves adjusting the electric power of the motors for rotating the screws.

Presentation of the invention

An object of the present invention is to overcome the aforementioned drawbacks by proposing a transport device that no longer requires a flex-resistant drive shaft and no longer requires protective sleeves.

For this purpose, the subject of the invention is a transport device according to claim 1.

Thanks to the invention, the drive shaft is designed to withstand only twisting, which can significantly reduce its dimensions and therefore its mass. Therefore, less material is needed to make the tree, which reduces its manufacturing cost and its size.

In addition, thanks to the invention, the drive shaft is no longer exposed to the driver of the machine which allows to remove the protective sleeves. Therefore, the dimensions of the screws and those of the electric motors for rotating said screws can be reduced.

Another advantage of the invention is also to facilitate the maintenance of the machine and to increase the service life of the parts. Indeed, thanks to the invention, the drive shaft, the displacement screws and the movement slides are protected against all kinds of deposit or projection such as dust or glue when the transport device according to the invention. invention is in the sizing station.

Other objects and advantages of the invention will appear more clearly in the description of an embodiment, a description which will be made with reference to the accompanying drawings.

In order to define some terms introduced in the present description and describing the position of certain elements within the folder-gluer, we will quote the appellations "driver side" (CC) and "Conductive opposite side" (COC) used to refer to a designated side with respect to the longitudinal center axis of the machine. This choice makes it possible to avoid any confusion arising with the conventional left and right denominations depending on the point of view of the observer. In a similar perspective, the orientation of certain movements or parts will be described by the usual terms "longitudinal" and "transversal" always referring to the median axis of the machine whose direction is determined by that of the scrolling of the elements. plate. Finally, it will also be specified that the terms "upstream" and "downstream" refer to the direction of movement of the plate elements in the folder-gluer.

Brief description of drawing figures

• The figure 1 is a perspective view of a lower conveyor according to the state of the art;
• The figure 2 is a perspective view of a lower conveyor according to the invention;
• The figure 3 is a cross-sectional view along the median plane of the figure 2 .

Best way to realize the invention

The figure 1 illustrates a lower carrier 1 according to the state of the art. The arrow 8 indicates the running direction of the plate elements. Such a conveyor generally comprises two longitudinal frames 1a, 1b parallel and distant from each other. Each frame has two large faces: an inner face and an outer face, the inner face of a frame being turned towards the inner face of the other frame. In the example, the frame 1a is located on the opposite side to the conductor and the frame 1b is located on the driver's side. Between the two frames 1 a, 1 b are arranged transversely two parallel cylindrical displacement slides 2, three pairs of parallel displacement screws 3 and a drive shaft 4. The displacement slides 2 are embedded at each of their ends to the racks. 1a, 1b, they are intended to support three longitudinal longitudinal side members 6a, 6b, 6c mounted side by side and each supporting an endless conveyor belt 7 resting on a horizontal hard plane, preferably a series of rollers (not shown). Each longitudinal spar is movable transversely between the frames 1 a, 1 b, along the slideways 2, this depending on the size of the blanks to be treated.

Bearing devices (not shown) cutouts against the conveyor belts 7 are arranged above certain portions of the longitudinal members 6a, 6b, 6c. These support devices may consist of a series of rollers held down by springs or an endless belt whose lower strand is pressed downwards.

To modify the transverse position of the longitudinal members 6a, 6b, 6c, these are mounted in helical connection with the displacement screws 3. In fact, the transverse movement of each spar is controlled by a pair of parallel screws 3 whose threaded portions are respectively engaged in transverse threaded holes of the spar, which screws are fixed in translation but free in rotation between the frames 1 a, 1 b. To rotate the screws 3, one or more electric motors are provided (not shown).

Each endless conveyor belt 7 is supported by rollers and a drive pulley 5. The drive pulleys 5 are coaxial and rotatably mounted on their respective spars. To drive the conveyor belts 7, the drive shaft 4 is rotatably mounted between the frames 1a, 1b and engaged in the drive pulleys 5. In the example, the shaft 4 has a hexagonal section in cooperation of shape with a transverse orifice formed in the axis of each drive pulley 5. Thus, when a spar 6a, 6b or 6c moves laterally under the action of a pair of adjusting screws 3, it slides along the slideways 2 and along the drive shaft 4.

For safety reasons, parts of the drive shaft 4 exposed to the driver of the machine are engaged in two sleeves 4a, 4b. Each sleeve 4a, 4b is in the form of a volute spring recessed at both ends. The COC sleeve, noted 4a, has one end secured to the frame 1a and the other end secured to the spar 6a, that is to say the spar closest to the frame 1a. The sleeve CC, noted 4b, has one end secured to the frame 1b and the other end secured to the spar 6b, that is to say the spar closest to the frame 1b. Thus, when the shaft 4 is rotated under the action of an electric motor (not shown), the sleeves 4a, 4b prevent any direct contact of the driver of the machine with the drive shaft 4, as well COC than CC

Note that the lateral displacement of the respective longitudinal members 6a, 6b causes the extension or compression of the respective springs 4a, 4b, it will also be noted that the shaft 6 is not protected between the respective longitudinal members 6a, 6b.

The Figures 2 and 3 illustrate a lower conveyor 10 according to the invention. The arrow 8 indicates the running direction of the plate elements. This carrier comprises two frames 10a, 10b parallel and distant from each other. Between the frames 10a, 10b are arranged two longitudinal longitudinal members 60a, 60b. Each spar 60a, 60b is mounted in sliding connection on a pair of common displacement rails 20 integral with a U-shaped profile 9. The profile 9 extends transversely between the two frames 10a, 10b, each end of the profile 9 being embedded in a respective frame 10a, 10b. In the example, the core 9a of the profile is horizontal while the wings 9b, 9c are vertical and turned downwards of the machine. The pair of slide rails 20 is mounted on the web of the profile 9 inside the U and extends transversely between the two frames 10a, 10b. Each slider 20 is a linear guide rail which, in cross section, has a biconcave shape such that a first concavity faces forward and a second concavity is turned towards the rear of the machine (see FIG. figure 3 ).

Each spar 60a, 60b has a respective opening 61a, 61b U-shaped in which the profile 9 can pass without interaction. To ensure the transverse guidance of the longitudinal members 60a, 60b, each spar is also provided with a pair of pads 21 in shape cooperation with the pair of sliding rails 20. Indeed, each pad 21 of a spar 60a, 60b presents in cross section a U-shaped with a horizontal core and two vertical wings turned upwards the machine such that each wing has in cross section a convexity turned towards the inside of the U so that the convexities of a shoe 21 cooperate with the concavities of a displacement slide 20 to form a slide connection.

Each spar 60a, 60b supports rollers (not shown), part of which defines a horizontal hard plane 71 for guiding an endless conveyor belt 70. The driving of the belt 70 is provided by a driving pulley 50, which is driven by rotation by a drive shaft 40 of hexagonal section. Each pulley 50 is mounted in sliding connection with the drive shaft 40. The drive shaft 40 extends transversely between the two frames 10a, 10b, each end of the shaft 40 being mounted free to rotate in a respective frame 10a, 10b. One of the ends 41 of the shaft 40 passes through the frame 10a to be secured to an electric motor (not shown).

According to the invention, the shaft 40 is located at least partly between the wings 9b and 9c of the section 9, under the core 9a. With this arrangement, the drive shaft 40 is no longer apparent as in the state of the art, therefore, the driver of the machine can not interact with the shaft 40, not even between them. longitudinal members 60a, 60b since the shaft is protected along its entire length. As a result, traditional protective sleeves are no longer needed. In addition, the section 9 being designed to support the weight of the machine operator without bending, the shaft 40 has a lighter structure than in the state of the art. In practice, for a given machine width, it is possible to reduce the section of the drive shaft by at least 30%, thereby reducing the cost of manufacture and the size of the shaft.

In order to return the belt 70 towards the horizontal hard plane 71, the latter is directed downwards out of the pulley 50 so as to pass under the profile 9, rollers (not shown) guide the belt 70 on this path .

A pair of parallel displacement screws 30 are also provided for moving the respective longitudinal members 60a, 60b along the movement slides 20. The threaded part of each screw 30 is engaged in a transverse tapped hole of a respective spar so as to form a helical connection between said screw 30 and said spar, each screw being fixed in translation and free in rotation between the frames 1 a, 1 b. To rotate the screws 30, one or more electric motors are provided (not shown).

Advantageously, the displacement screws 30 are located at least partly between the wings 9b and 9c of the profile 9, under the core 9a.

In a folder-gluer machine, the lower conveyor is generally surmounted by an upper belt conveyor facilitating the conveying of the cuts taken between the belts of the lower and upper conveyors. Advantageously, the invention also applies to the upper conveyor.

Claims (13)

1. Transport device (10) for transporting sheet elements within a folder-gluer comprising two longitudinal frames (10a, 10b) between which there are positioned one or more sliding rails (20), one or more shifting spindles (30) and a drive shaft (40), at least one longitudinal transport beam (60a, 60b) supporting at least one endless conveyor belt (70), said longitudinal transport beam (60a, 60b) being mounted in sliding connection on said sliding rails (20) and said drive shaft (40) and in helical connection to said shifting spindles (30), and means of protecting the drive shaft (40), characterized in that said protective means transversely connect the two longitudinal frames (10a, 10b).
2. Transport device according to claim 1, characterized in that at least one of said sliding rails (20) is secured to said protective means.
3. Transport device according to claim 2, characterized in that said protective means comprise a profile section (9).
4. Transport device according to claim 3, characterized in that said profile section (9) has a concave face facing toward the drive shaft (40) and in which at least a part of said shaft is housed.
5. Transport device according to claim 3 or 4, characterized in that said profile section (9) in cross section has a web (9a) and at least one flange (9b, 9c).
6. Transport device according to claim 3 or 4, characterized in that said profile section (9) in cross section has a web (9a) and at least two flanges (9b, 9c).
7. Transport device according to claim 6, characterized in that said drive shaft (40) is situated at least partially between said two flanges (9b, 9c).
8. Transport device according to one of claims 5 to 7, characterized in that said drive shaft (40) is situated under said web (9a).
9. Transport device according to claim 5 or 6, characterized in that at least one of said sliding rails (20) is secured to said web (9a).
10. Transport device according to one of claims 5 to 9, characterized in that at least one of said shifting spindles (30) is situated under said web (9a).
11. Transport device according to claim 6, characterized in that said shifting spindle (30) is situated at least partially between said two flanges (9b, 9c).
12. Transport device according to one of claims 1 to 11, characterized in that said transport device is a lower conveyor.
13. Transport device according to one of claims 1 to 11, characterized in that said transport device is an upper conveyor.

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