U.S. patent application number 12/373820 was filed with the patent office on 2009-10-01 for auxiliary drive device for the conveying of sheetson a feed table of a cutting press.
Invention is credited to Jean-Claude Rebeaud.
Application Number | 20090243208 12/373820 |
Document ID | / |
Family ID | 37507674 |
Filed Date | 2009-10-01 |
United States Patent
Application |
20090243208 |
Kind Code |
A1 |
Rebeaud; Jean-Claude |
October 1, 2009 |
AUXILIARY DRIVE DEVICE FOR THE CONVEYING OF SHEETSON A FEED TABLE
OF A CUTTING PRESS
Abstract
An auxiliary drive device for a machine for processing
sheet-like articles. The machine comprises a feed table provided
with at least one lower drive belt for transporting a layer of
sheet-like articles. A frame of the drive device is arranged above
the feed table of the processing machine. The frame supports at
least one upper drive belt which cooperates with the lower drive
belt(s) for transporting the layer of sheet-like articles by
exerting a pressing and driving force on the upper surface of the
layer. A mechanism drives the upper belt(s) in synchronism with the
lower drive belt(s). A machine for processing sheet-like articles
comprises a feed table provided with at least one lower drive belt
for transporting a layer of sheet-like articles and comprises such
an auxiliary drive device.
Inventors: |
Rebeaud; Jean-Claude; (Le
Mont, CH) |
Correspondence
Address: |
OSTROLENK FABER GERB & SOFFEN
1180 AVENUE OF THE AMERICAS
NEW YORK
NY
100368403
US
|
Family ID: |
37507674 |
Appl. No.: |
12/373820 |
Filed: |
July 16, 2007 |
PCT Filed: |
July 16, 2007 |
PCT NO: |
PCT/EP07/06292 |
371 Date: |
January 14, 2009 |
Current U.S.
Class: |
271/273 ;
271/264 |
Current CPC
Class: |
B65H 11/002 20130101;
B65H 5/023 20130101; B65H 2404/254 20130101; B65H 5/24 20130101;
B65H 2404/261 20130101 |
Class at
Publication: |
271/273 ;
271/264 |
International
Class: |
B65H 5/02 20060101
B65H005/02 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 17, 2006 |
EP |
06014833.5 |
Claims
1. A machine for processing sheet-like articles using an auxiliary
drive device, the machine comprising a feed table for feeding of
the articles over the table, at least one lower drive belt on a
path over the table; for transporting a layer of the sheet-like
articles of the auxiliary drive, the auxiliary drive device
comprising a frame arranged above the feed table, wherein the frame
supports: at least one upper drive belt positioned and operable to
cooperate with the lower drive belt(s) and the layer then at the
table for transporting the layer of sheet-like articles by exerting
a pressing and driving force on an upper surface of the layer; and
a drive mechanism operable for driving the upper belt(s) (15) in
synchronism with the lower drive belt(s) and against the surfaces
of the layer.
2. The machine of claim 1, wherein the auxiliary drive device
comprises a movable carriage movable for formatting the or each
upper drive belt.
3. The machine of claim 1, wherein the auxiliary drive device
comprises transmission and pressure pulleys movable in a direction
perpendicular to the surface of the or each upper drive belt.
4. The machine of claim 1, wherein the auxiliary drive device
comprises a device operable for adjusting the pressing force
exerted by the upper drive belt on the layer.
5. The machine of claim 4, wherein the device operable for
adjusting the pressing force comprise a pneumatic jack.
6. The machine of claim 1, further comprising a positioning shaft
and the device is raised by pivoting of the frame about the
shaft.
7. (canceled)
Description
[0001] The present invention relates to an auxiliary drive device
for transporting sheets of paper or cardboard which are arranged in
layer form, on the feed table of a cutting press.
[0002] In the hitherto known cutting presses, an example of which
is shown schematically in FIG. 1, the sheets to be processed are
taken from the top of a stack 1, arranged in layer form 3 and then
transported on a feed table before being introduced into the
grippers 4 of the transportation members 5 of the press cutting
station. Thus the document EP1170228 describes an example of a
sheet-by-sheet feeding device for arranging said sheets in layer
form; and the document EP0680906 describes an example of the
transportation member of the press cutting station, which uses
gripping bars.
[0003] The devices for arranging the sheets in layer form and
feeding the layer are shown in greater detail in FIGS. 2 and 3. The
stack 1 supplies the layer 3 by means of the suction unit 2, the
top of the stack 1 being kept at a constant level owing to raising
of the stack-support plate 6 driven by a motor 7. The sheet 8 on
top of the stack 1 is gripped at the rear and then pushed forwards
by the suction unit 2 so as to form the layer 3, the front part 9
of the sheet 8 being slid underneath the previous sheet 10.
[0004] The sheets of the layer 3 are obviously precisely positioned
longitudinally and laterally by a positioning device (not shown).
The documents EP0669274, EP1044908 and EP1151833 describe examples
of the device for positioning the sheets from which the layer 3 is
formed. As illustrated in these documents, this positioning
operation is performed at one of the ends of the feed table and may
be achieved either by means of front and side stops against which
the edges of the sheet to be introduced into the press cutting
station rest or using a more sophisticated system which does not
require stoppage of the sheets.
[0005] The feed tables known hitherto generally comprise an
inclined platen 12 which may be for example a metal plate or a
wooden board which acts as a support for the upper section of at
least one drive belt 11. Where several belts 11 are present, they
are arranged side-by-side over the width of the inclined surface 12
which therefore supports the upper sections of each of the belts
11.
[0006] In order to perform transportation of the sheets of the
layer 3 onto the feed table 12, frequently at least one upper
auxiliary pressing element 13 is used. The upper auxiliary pressing
element(s) 13 is/are mounted on a frame so that it/they can be
adjusted positionwise above the upper section of the drive belt or
each of the drive belts 11. These auxiliary pressing elements 13
are most often designed in the form of sliding blocks, rollers or
small belt conveyors, the pressure of which on the layer 3 of
sheets to be transported may sometimes be adjusted. An example of
an upper auxiliary pressing element 13 is described in the document
EP0684201. When positioning by means of contact against a stop is
used, often a rotating brush is used, said brush being positioned
so that its bristles give way when the front edge of the first
sheet of the layer comes into contact with the stop, thus avoiding
damage to the edge of the sheet as a result of an excessively
brusque thrusting action by the transportation members.
[0007] In the known devices the auxiliary pressing elements 13 only
have the function of pressing against the layer 3 so that it is
flattened against the upper section of the drive belt or each of
the drive belts 11.
[0008] The friction is the decisive parameter for the driving force
of the layer 3. Moreover the upper section of the drive belt or
each drive belt 11 for the sheets project(s) only slightly beyond
the surface of the inclined plane 12 so as to ensure correct
transportation of low-weight paper.
[0009] In the case where the sheets are not composed of flexible
material such as low-weight paper or cardboard and moreover have a
very slippery surface, the contact between the layer 3 and the
upper sections of the belts 11 is no longer sufficient to ensure
precise and uniform conveying of the layer 3, as shown in FIG. 5
for a device comprising two drive belts 11. This may occur in
particular with sheets of corrugated cardboard which are pasted
together. It is thus required to increase significantly the
pressing force Fv of the upper auxiliary pressing elements 13, this
resulting in some cases in localized crushing of the corrugated
cardboard, which is unacceptable nowadays.
[0010] The object of the present invention is to overcome the
aforementioned drawback so that conveying of the sheets is
performed correctly, whatever the material from which they are
made, and without damaging them.
[0011] To this end, the present invention relates to an auxiliary
drive device for a machine for processing sheet-like articles, in
accordance with that stated in claim 1, and also to a press for
cutting sheet-like articles, in accordance with that stated in
claim 7. Claims 2 to 6 define preferred embodiments of the
invention.
[0012] The invention will be understood better with reference to a
preferred embodiment provided by way of a non-limiting example and
illustrated by the accompanying drawings in which:
[0013] FIG. 1 is a schematic view of an existing cutting press;
[0014] FIG. 2 is a schematic view of the different stations of an
existing cutting press;
[0015] FIGS. 3 and 4 are schematic views of an existing device for
arranging the sheets in layer form and for feeding the layer;
[0016] FIG. 5 illustrates schematically the problem which is posed
in some cases by high-weight sheet-like articles for the existing
devices.
[0017] FIGS. 6, 7 and 8 show different schematic illustrations of a
device according to the invention; and
[0018] FIG. 9 shows an embodiment of the driving mechanism of a
device according to the invention.
[0019] From the point of view of terminology, in order to avoid any
confusion in the description which follows, the terms "upstream"
and "downstream" will be defined with reference to the direction of
displacement of the sheets in layer form. This layer moves from the
upstream downstream, along the main axis of the machine. The terms
"longitudinal" and "transverse" will also be defined in relation to
the main axis of the machine, and the expression "sheet-like
articles" is considered to be equivalent to the expression "sheets
of paper or cardboard", this so as to avoid complicating the
description by mentioning constructional details which are not
directly related to the invention and are well-known to the person
skilled in the art.
[0020] The invention therefore concerns machines for processing
sheet-like articles, of the type comprising a feed table provided
with at least one lower drive belt 11 for transporting a layer 3 of
sheet-like articles, such as the cutting press shown in FIG. 1 and
described above. These machines may reach output speeds ranging
from 8,000 sheets per hour to 12,000 sheets per hour when the
machine is equipped with a sophisticated positioning device which
does not require stoppage of the sheets.
[0021] An auxiliary drive device according to the invention is
shown in FIG. 6. According to the invention, this device comprises
a frame intended to be arranged on top of the feed table of the
processing machine. According to the invention, this frame supports
at least one upper drive belt 15. If necessary in the example of
embodiment of the invention shown in FIG. 6, it supports two of
them. The upper drive belts 15 are driven by a shaft 16 in
synchronism with the lower drive belt(s) 11.
[0022] In the example of embodiment of the invention shown in FIG.
6, the device comprises two movable carriages which may slide on
two guide bars 26. Advantageously, and as shown in FIG. 6, one of
the carriages is a movable formatting carriage 17 which allows
deviation of the upper belt or each upper belt 15 so that it does
not rest on top of the layer 3 and only drives the latter as far as
the point where the most downstream sheet 14 of the layer 3 is
taken up by the positioning device and then the gripper bar 4 of
the transportation members 5. The movable formatting carriage 17
therefore allows optimum conveying of the layer 3 whatever the
format of the sheets forming it. In the example of embodiment shown
in FIG. 6 the movable formatting carriage 17 is the carriage which
is situated furthest downstream.
[0023] As shown schematically in FIG. 7, this movable carriage
comprises at least one transmission pulley 21 allowing formation of
an endless belt 15, as well as at least one roller 29 pushed by a
resilient member 22 ensuring tensioning of the belt 15.
[0024] Optionally, the auxiliary device according to the invention
is able to be raised by means of the pivoting of the frame about a
shaft 25 situated close to one of its ends. In FIG. 6 the shaft 25
is situated close to the downstream end of the frame, but it is
entirely feasible to implement the invention by arranging this
shaft close to the upstream end of the frame. When the device is
raised, the operator of the processing machine is able to remove
easily any sheets which might not be properly separated in the
layer 3 or the spacing of which might not be uniform.
[0025] Preferably, the device comprises one or more pressure
pulleys 20 which exert a pressure on the drive belt 15 and are
movable in a direction perpendicular to the surface of the belt 15,
so as to be able to be adapted to the thickness of the layer 3 and
increase as far as possible the surface area of the layer 3 subject
to the pressing and driving force of the belt 15.
[0026] A cheek 30 arranged on the movable carriage shown in FIG. 8
supports all the different transmission and pressure pulleys (20,
21, 31, 32). The combination of this set of pulleys, the cheek 30
and the drive belt 15 thus forms a bogie.
[0027] Preferably, the device comprises means 23 for adjusting the
pressing force exerted by the upper drive belt 15 on the layer 3.
These means 23 for adjusting the pressing force may relieve the
weight of the device or on the contrary even press onto the layer 3
in addition to the intrinsic weight of the device. In the example
of embodiment shown in FIG. 8, the means 23 for adjusting the
pressing force consist of a pneumatic jack, the pressure of which
may be adjusted. In this example of embodiment of the invention,
the bogie is therefore movable. The working position of the bogie
is defined by two arms 28 which are hinged at one of their ends on
an extension 27 of the movable carriage 17 and hinged at the other
of their ends on a shaft, the bogie assembly being also able to
pivot about said shaft so as to press the surface of the layer 3 in
the best possible manner.
[0028] The mechanism for driving the upper drive belt(s) 15 may
take different forms, in particular forms involving a mechanical
connection of the drive shaft 19 of the lower drive belt(s) 11 to
the drive shaft 16 of the upper drive belt(s) 15. FIG. 9 shows an
example of embodiment of such a mechanical connection performed by
means of two friction wheels 24.
[0029] The upper drive belt(s) 15 of the device according to the
invention exert a driving force on top of the layer 3, this
ensuring correct conveying of the latter whatever the material of
the sheet-like articles and without exerting an excessive pressing
force. It is thus possible to use a small number of upper drive
belts 15, and even decrease the number of lower drive belts 11 of
the feed table of the processing machine.
[0030] Moreover, the device according to the invention has made it
possible to identify and solve another technical problem. In the
systems for transporting a layer of sheet-like articles for the
feed tables of existing machines, it was noted that there was a
slight increase in the speed of the sheet-like articles during
transportation thereof, as well as a difference in speed of the
articles depending on the thickness of the layer and the number of
superimposed articles. This was due to the fact that the pulley for
introducing the sheet-like articles onto the feed table has the
effect of a side rim. The sheet-like articles were thus slightly
accelerated by the sheet-like articles which were slid underneath
them and in the end the layer 3 advanced at a speed slightly faster
than that of the lower drive belt 11. Moreover the difference in
speed between the layer 3 and the belt 11 depended on the number of
sheet-like articles stacked within the thickness of the layer and
therefore varied between the first article in the layer and the
economy speed.
[0031] The device according to the invention is able to ensure much
more precise transportation than the existing systems owing to
synchronization of driving of the upper belts 15 with driving of
the lower belts 11. This facilitates management of the sheet-like
articles by the positioning device, allowing a better estimation of
the position of each sheet-like article within the layer 3 and the
moment when the positioning device must take them up.
[0032] This problem did not constitute the main problem which the
invention proposed to solve a priori, but solving thereof
constitutes an additional undeniable advantage of the devices
according to the invention compared to the existing devices.
* * * * *