LATERAL POSITIONING DEVICE FOR A SHEET ELEMENT

Abstract

A lateral positioning device (100) for a sheet element (20, 20′) in a sheet element processing machine; a detector lever (130) articulated relative to a horizontal axis, which performs a descending movement from a high position to a low position; a first end (132) of the detector lever (130) contacts, in a low position of the lever, with an upper face of the sheet element. A second end (133) of the detector lever (130) is fitted with a target (135) that cooperates with a position detector (140) to generate a signal dependent on the thickness of the sheet element (20, 20′) and the number of sheet elements (20, 20′) present at the level of the first end (132) of the detector lever (130).

Claims

1. A lateral positioning device for positioning a sheet element in a sheet element processing machine, the device comprising: a detector lever articulated relative to a horizontal axis and configured to perform a descending movement from a high position to a low position; a first end of the detector lever configured and operable to be articulated, in the low position, to contact an upper face of the sheet element; and a second end of the detector lever being fitted with a target located and configured for cooperating with a position detector to generate such that the detector generates a signal dependent on and corresponding to the thickness of the sheet element and to the quantity of sheet elements present at the level of the first end of the detector lever in the low position.

2. The device according to claim 1, further comprising a braking system configured and operable to slow the descending movement of the detector lever.

3. The device according to claim 2, wherein the braking system comprises a Foucault brake.

4. The device according to claim 1, further comprising: a shaft at the horizontal axis around which the detector lever is rotatably mounted, return means at the shaft and configured to exert a force for generating the descending movement of the detector lever.

5. The device according to claim 1, further comprising the second end of the detector lever is equipped with a metal target, which cooperates with a detection head of the position detector and the detection head is fitted with an inductive proximity sensor.

6. The device according to claim 1, further comprising a main lever having a main first end and a support roller carried at the main first end of the main lever; The first lever is located and configured such that at the end of descending travel of the first end of the main lever, the first end of the main lever includes: a first lowered configuration at which the first end of the main lever is located and configured for pressing the support roller against the upper face of the sheet element and so as to drive the sheet element laterally, and a second raised configuration to avoid crushing the sheet element.

7. The device according to claim 6, wherein the detector lever is mechanically coupled to the main lever and the detector lever is movable by and along with the main lever.

8. The device according to claim 7, further comprising a selection system located and configured for allowing the detector lever to be raised off the sheet element irrespective of the position of the main lever.

9. The device according to claim 6, further comprising a delivery wheel located and configured for moving the sheet element flush against a lateral feed stop.

10. The device according to claim 9, further comprising in a first configuration, the support roller is located and configured for coming to rest against the upper face of a sheet element arranged on a support surface between the support roller and the delivery wheel, to allow gripping of the sheet element which is driven by the delivery wheel in a direction of and as far as the lateral feed stop for lateral positioning of the sheet element against the lateral feed stop.

11. The device according to claim 1, further comprising: a pusher located above a support surface, the pusher being configured to move from a rest position thereof to a working position thereof in which a sheet element arranged on the support surface is at the same height as is the pusher; and a drive system perform a reciprocating movement in the lateral direction, across a movement path of the sheet, the drive system cooperates with the pusher only in the working position of the drive system such that the pusher performs a reciprocating motion between a retracted position and an advanced position, wherein the pusher in the advanced position is arranged to push a sheet element arranged on the support surface up to a lateral position predetermined by the advanced position.

12. The device according to claim 3, further comprising in a second configuration, at the end of descending travel of the first end of the main lever, the support roller remains above the delivery wheel and at a distance from the delivery wheel, preventing the support roller from resting against the upper face of the sheet element then between the support roller and the delivery wheel.

13. The device according to claim 11, wherein, in the first configuration, the pusher is in the rest position thereof.

14. The device according to claim 13, wherein in the second configuration, the pusher is in the working position thereof.

15. A sheet element processing machine comprising a device according to claim 1, mounted in an introduction station upstream of a processing station.

16. The device according to claim 12, wherein in the second configuration, the pusher is in the working position thereof.

17. A sheet element processing machine comprising a device according to claim 12, mounted in an introduction station upstream of a processing station

Description

DESCRIPTION OF THE DRAWINGS

[0040] The invention will be better understood and its various advantages and characteristics will arise more clearly from the description below of the non-limiting exemplary embodiment, with reference to the attached Figures in which:

[0041] FIG. 1 illustrates in side view, partly in cross section, a lateral positioning device according to the invention in the first configuration, with the first end of the main lever lowered;

[0042] FIG. 2 is a side view of the lateral positioning device of FIG. 1 in the first configuration, with the first end of the main lever raised;

[0043] FIG. 3 illustrates in side view, partly in cross section, the lateral positioning device in FIG. 1 in the second configuration, with the first end of the main lever lowered;

[0044] FIG. 4 is a side view of the lateral positioning device in the second configuration, with the first end of the main lever raised;

[0045] FIG. 5 is a partial view from above of a feed table of the lateral positioning device in FIGS. 1 to 4;

[0046] FIG. 6 is a section view in direction VI-VI of the lateral positioning device in FIG. 5;

[0047] FIG. 7 is a section view in direction VII-VII of the lateral positioning device in FIG. 5;

[0048] FIG. 8 is a section view in direction VIII-VIII of FIG. 6.

DETAILED EXPLANATION OF PREFERRED EMBODIMENTS

[0049] In the present text, the term “lateral” designates a direction perpendicular to the direction of advance of the sheet elements, such as paper sheets, in a processing machine, and in particular in an introduction station 10 partly visible in FIG. 5. In FIG. 5, arrow P designates the direction of advance of the sheets to be processed from upstream to downstream, arrow L1 designates the left lateral side or CC for “operator's side”, and arrow L2 designates the right lateral side, or COC for “side opposite the operator”.

[0050] The lateral positioning device 100 visible in FIG. 5 is in this example located on the operator's side and intended to ensure the good lateral positioning of a sheet element, such as a sheet of printed cardboard, before its processing, such as cutting by platen, while the good longitudinal positioning (in direction A) is ensured by a front positioning device (not shown).

[0051] The operating principle of the lateral positioning device 100 is explained in relation to FIGS. 1 to 4 on which the lateral positioning device 100 is viewed from upstream. A delivery wheel 102 which turns rhythmically alternately clockwise and anticlockwise forms the drive means for introducing a sheet element 20; in FIGS. 1 and 2, the lateral positioning device 100 is in the first configuration, able to perform the lateral adjustment of a sheet element 20 which may be of widely varying thickness, in particular between 0.2 mm and 4 mm. Conventionally, this is a flat printed cardboard with a multitude of subassemblies, which will be precut in the next unit (not shown) to form the cardboard flaps which after assembly will constitute the packaging.

[0052] In FIG. 1, the sheet element 20 rests on a support surface front abutment 101 with a window at the position of the delivery wheel 102, to allow the periphery of the delivery wheel to come into contact with the lower face of the sheet 20 in order to drive the sheet from the lateral side L1 using the delivery wheel 102. The sheet is pulled from the lateral side L2 via the COC tab. A main lever 110 mounted rotatably around direction P on its pivot 111 of horizontal axis, at its first end 112 (on the right in FIGS. 1 to 4 and 6) has a support roller 114, here shown in the form of a roller bearing, placed above the receiver support. Here the main lever 110 is articulated around a horizontal axis. On swiveling of the main lever 110 in the direction of lowering of the first end 112, the arrangement allows the support roller 114 to be aligned with the delivery wheel 102 (see FIGS. 1 and 3) with the two axes of rotation of the support roller 114 and the delivery wheel 102 parallel. More precisely, in the lowered position of the first end 112, the rotation axis of the support roller 114 is aligned with the rotation axis of the delivery wheel 102, as shown on FIG. 1, while the high position of the first end 112 is visible on FIG. 2.

[0053] In FIG. 1, in the low position of the first end 112, a slight downward back-pressure is applied by the support roller 114 so as to lightly grip the sheet 20 between the delivery wheel 102 and the support roller 114, and by this gripping ensure transfer of the sheet in the direction of the rotation movement of the delivery wheel 102, which is now anticlockwise, until the sheet comes to rest with its lateral edge against the lateral feed stop 121 facing the delivery wheel 102. In this position, the sheet 20 is arranged laterally in the desired position. The low position of the first end 112 is first adjusted according to the thickness of the sheet 20. The main lever 110 is driven by an electric motor and cams, allowing its pivoting with a cadenced rise and fall following the machine cycle for each packaging element 20.

[0054] Thus, in the first configuration, the lateral positioning device 100 functions in pull mode, since the sheet is wedged in the desired lateral position by pulling the packaging element 20, gripping and advancing it between the support roller 114 and the delivery wheel 102 until the packaging element 20 comes to rest against the lateral feed stop 121.

[0055] In parallel with the cadenced movement of the main lever 110, there is a cadenced movement in the same rhythm of a secondary lever coupled to the main lever 110 and called the detector lever 130. This detector lever 130 is parallel to the main lever, and is situated next to and upstream of the main lever 110 relative to the direction of advance P of the sheet elements 20. The detector lever 130 swivels around the direction P on its pivot 131 of horizontal axis, and at its first end 132 (at the right in FIGS. 1 to 4 and 6) has a detector roller 134 formed by an idler wheel placed above the support surface 101.

[0056] On swiveling of the main lever 110 in the direction of lowering of the first end 112, the arrangement allows the first end 132 of the detector lever 130 to descend in order to enable the detector roller 134 to come to rest precisely against the upper face of the sheet 20, as shown in FIG. 1. In this position, the second end 133 of the detector lever 130 is raised. A metal target 135 is arranged on this second end 133. This metal target 135 belongs to a proximity detector 140, which is for example an inductive sensor and is situated below a detection head 141. This detector 140 is calibrated to measure the distance d between its lower face 142 and the metal target 135. The value d, which is measured when the detector roller 134 touches the sheet 20 allows very precise calculation of the thickness e of this packaging element.

[0057] The mechanical coupling between the main lever 110 and the detector lever 130 is ensured, on lifting of the main lever 110, via a pin 116 arranged on the side of the first end 112 of the main lever 110 and protruding in the upstream direction. This pin 116 extends over a sufficient length to be able to cooperate with the first end 132 of the detector lever 130 by pressing under a stud 136 present on this first end 132 of the detector lever 130, such that when the first end 112 of the main lever 110 rises, the pin 116 pushes the stud 136 up and causes it to rise, driving the first end 132 of the detector lever 130 in its travel.

[0058] When the main lever 110 descends, the descent of the pin 116 breaks the support of the stud 136 by the pin 116, leaving the first end 132 of the detector lever 130 free to descend at least as low as the position of the pin 116. The arrangement of the levers 110 and 130 is such that, when the first end 112 of the main lever 110 is in the lowest position, the support roller 114 is in contact with the sheet 20, the pin 116 is lower than the stud 136, while the detector roller 134 is in contact with the upper face of the sheet 20.

[0059] In order to force down the first end 132 of the detector lever 130 when the stud 136 is not coupled to the pin 116, the shaft 131 about which the detector lever 130 pivots is surrounded by a pre-stressed coil spring 137. This prestressing also allows generation of a support force guaranteeing the contact of the detector roller 134 on the sheet 20 and hence a correct thickness measurement.

[0060] A selection system with the pin 116 and support 117 for the pin 116 allows the detector lever 130 to be raised irrespective of the position of the main lever 110.

[0061] To ensure contact between the detector roller 134 and the sheet 20 without marking the upper face of the sheet, arrangements are made to slow down the descending movement of the second end 132 of the detector lever 130. To this end, a passive braking system 150 is used. In the embodiment shown, this is a permanent magnet brake or Foucault brake, functioning as follows: between the second end 133 and the pivot 131, the detection lever 130 has a braking portion 138 formed by a metal plate oriented vertically upwards. Also, next to the detection head 141, the device 100 has two permanent magnets in the form of a frame 152 which are parallel to each other and extend vertically, delimiting an air gap in which the braking portion 138 engages. The surface area of the braking portion 138 in the gap is variable and increases during the descending movement of the detector roller 134, which slows the descent.

[0062] By monitoring the value of the thickness e measured for each new packaging element 20 arriving at the lateral positioning device 100, where necessary the processing machine can be stopped so that an operator can verify and extract an incorrect sheet 20 or incorrect set of sheets 20.

[0063] In FIG. 3, the main lever 110 has been adjusted such that, in the low position of the first end 112, a slight back-pressure is exerted by the support roller 114 on the sheet 20′ which is thicker than the sheet 20 of FIGS. 1 and 2.

[0064] Also, the lateral positioning device 100 functions in a second configuration shown in FIGS. 3 and 4. In this case, the aim is to avoid the pressurized support of the support roller 114 on the sheet 20′, for example because this packaging element 20′ has a low density, its surface is easily marked by an imprint under the pressure of a roller. This is the case in particular if the packaging element 20′ contains one or more layers of corrugated cardboard. In the example shown, this packaging element 20′ has a thickness e′ which is greater than the thickness e of the sheet 20 shown in FIGS. 1 and 2. This thickness e′ corresponds to a distance d′ between the metal target 135 and the detection head 141.

[0065] In this second configuration, the support roller 114 is raised relative to its position in the first configuration, so that it is not able to touch the upper surface of the sheet 20′ when the first end 112 of the main lever 110 is lowered. To compensate for this uplift of the support roller 114 and still allow the detector roller 134 to descend to the upper face of the sheet 20′, the height position of the pin 116 has also been shifted by turning its support 117 through 180° around a horizontal axis, parallel to the axis of rotation of the delivery wheel 102.

[0066] The lateral feed stop acts as a pusher element 121 and is arranged just above the support surface 101 and on the other side of the delivery wheel 102 relative to the support roller 134. This pusher element 121 has a thrust face against which the lateral edge of the sheet 20′ comes to rest. This pusher 121 executes a horizontal translation movement (from left to right in FIGS. 3 and 4) from a retracted position, shown in FIGS. 3 and 4, to an advanced position which is set such that at the end of travel, the sheet 20′ is arranged laterally in the desired position.

[0067] Thus in the second configuration, the lateral positioning device 100 functions in pusher mode, wherein the sheet 20′ is wedged in the desired lateral position by pushing this packaging element 20′, the pusher 121 is transferred from the retracted position to the advanced position until the packaging element 20′ is brought into the lateral position corresponding to the end of travel (advanced position) of the pusher 121.

[0068] In this second configuration, the thickness of the sheet present on the feed table is monitored in the same way as described above in relation to the first configuration. To understand the transition from the first configuration (pull mode) to the second configuration (push mode) and vice versa, reference is made to FIGS. 5 to 8.

[0069] As is shown in FIG. 7, the pusher 121 is blocked in the forward position and serves as a stop for the puller. An adjustment screw 150 allows, by its rotation, the raising or lowering of an adjustment support 152 with a beveled lower edge which cooperates with a beveled upper edge of the block forming both the pusher and the lateral feed stop 121. Thus the descent of the adjustment support 152 causes the pusher 121 to advance in horizontal translation towards the right in FIGS. 6 and 7.

[0070] The pusher 121 is fixedly attached to the slider 155, which is itself fixed to the roller of the cam 156 (see FIG. 6). The position of FIGS. 6 and 7 corresponds to the second abovementioned configuration of the lateral positioning device. In this case, the cam roller 156 is housed in a receiver space for the cam 160, which moves in a permanent cyclic movement, in a position allowing a reciprocating movement of slider 155 between the right and left. This reciprocating movement allows the pusher 121 to perform the positioning of the sheet 20′ by pushing. To transfer to the first configuration, the adjustment support 152 is lowered via the adjustment screw 150, causing the pusher 121 to advance towards the right into a position which remains in the receiver space of the cam 160, but this time the pusher 121 is not able to follow the movement of the cam 160 which turns idly because the cam 160 is no longer driving the pusher 121.

[0071] The introduction station 10 with the lateral positioning device 100 just described preferably comprises a further lateral positioning device located on the other side, at the same axial position as the lateral positioning device 100. Thus if the lateral positioning device 100 is on the operator's side, the additional lateral positioning device is on the side opposite the operator. In the first variant, the additional lateral positioning device is identical to the lateral positioning device 100, apart from adaptation to the side opposite the operator by modifying the structure of the lateral positioning device 100 by symmetry relative to the median vertical plane of the support surface 101. In a second variant, the additional lateral positioning device does not comprise the detector lever 130 and all elements of the system for detecting the presence of two superposed sheet elements and allowing monitoring of the thickness of the sheet 20 or 20′.

[0072] Advantageously, the additional lateral positioning device comprises (elements identical to those of the lateral positioning device 100 carry the same reference numeral): [0073] a lateral feed stop 121 protruding upward from the upper face of the support surface 101, [0074] a main lever 110 carrying at its first end a support roller 114 able to approach the delivery wheel 102 on a descending movement of the first end of the main lever 110, when the lateral edge of the sheet 20, 20′ is close to or against the lateral feed stop 121.

[0075] According to another preferred arrangement, such an additional lateral positioning device also comprises: [0076] a delivery wheel 102 for the sheet elements, having a rotation movement alternately in one direction or is then the other, for cadenced driving of each packaging element 20, 20′ in the direction of the lateral feed stop 121.

[0077] Preferably such an additional lateral positioning device also comprises: [0078] the pusher 121 arranged above the support surface 101, the pusher 121 is able to move from a rest position to a working position in which a packaging element 20, 20′ arranged on the support surface 101 is at the same height as the pusher 121, and [0079] a drive system, in particular a drive by cams, performing a reciprocating movement in the lateral direction and cooperating with the pusher 121 only in its working position, such that the pusher 121 performs a reciprocating movement between a retracted position and an advanced position, and the pusher is able to push a packaging element 20 and 20′ arranged on the feed table to a lateral position predefined by the advanced position (end of travel of pusher 121).

[0080] On use of the introduction station 10, several possibilities exist according to the size and type of packaging element supplied to the feed table. According to a second possibility, only the lateral positioning device 100 or only the additional lateral positioning device is used, each of which is placed either in the first configuration or in the second configuration.