Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
10~97~0
In the processing of flat objects, especially blanks m~de of stiff
material, often there is a need for objects which have been delivered in an
irregular sequence onto a belt, to b~e uniformly overlapped as a conveyor belt
carries them along.
It is the purpose of the invention to provide a device ~hich will
position the flat objects with the same degree of overlap.
The invention is a device for overlapping flat rigid objects
comprising a conveyor supported by a first conveyor element and a second
conveyor element, a displaceable kaffle means mounted above and bebween said
first acnveyor element and said second conveyor element, said second conveyor
element being upstream said baffle means, the conveyor forming a passage
through which said flat objects may pass in controlled manner, the second
conve~Dr element being adjustable to a position at a distanca from said baffle
which distance is less than the length of a single objeat, whereby the forae
applied to one of said cbjects by said second conve~or el3ment is transmitted
to said ba1e and the baf1e yields thus enlarging the passage and allowing
the object to pass therethrough.
In the devioe according to the invention, the baffle is controlled
without any special sensor and drive. The thrust applied to an object by the
rear drive element is used to actuate the baffle, so that it does not hold
back the objeat. The object, which is acted upon by the said rear drive
ele~ent, shields the next overlying object from the feed action of the r~Ar
drive element until the rear edge o the moving object leaves the rear drive
element. By altering the distance between the rear drive element and the
baffle, the degree of overlap may be determined. The closer the drive
element to the baffle, the greater the degree of overlap.
m e baffle preferably has a sloping stop. This kind of design
produces, at the baffle, a reaction force of the feed force applied to the
object, a force component of which raises the baffle against the force of
gravity and against an adjustable spring force.
Since uniform overlapping requires that the objects be backed up,
the speed of the drive elements is controlled by means of a sensor which
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senses the height of the backed-up objects. This speed is increased when
there is a large or an increasing back-up; it is reduced when the back-up
is small or decreasing.
Acoording to one embodiment of the invention, the same speed of the
two drive elements may be obtained, while the degree of overlap still remains
the same, by providing the two drive elements with a common conveyor belt
which, between the baffle and the rear drive element, is lower than a feed
conveyor.
The invention is explained hereinafter in greater detail in conjunc-
tion with the drawing attached hereto of a diagrammatic example of embcdiment
in side elevation.
Blanks 2 of stiff material are carried in an irregular arrangement
~with varying amLunts of overlap), on a conveyor belt 1, in the direction of
arr~w 3. The said blanks could be conveyed separate from each o~h3r. The
said blanks pass from conve~or belt 1 to a lcwer level, where they back up
and orm an accum~lation 4.
This accumwlation 4 forms in ront of a baffle 5 having a sloping
stop 6, as shown in the drawing. Arranged under the track, in the vicinity
of accum~lation 4 is a roller or second conveyor element 7 over which a
conveyor belt 10, passing over deflecting rollers 8, 9, runs. Between
second conveyor element or roller 7 and passage 12, formed by baffle 5,
conveyor belt 10 is offset in a downward direction in relation to the feed
plane at passage 12 and roller 7. Immediately ahead of passage 12, this
feed plane consists of a plate or grid 22 comprising recesses for belt
10 in the vicinity of drive element 7. The design of belt 10 may vary. It
may, for instance, consist of a plurality of separate narrow belts passing
upwardly through the grid in the vicinity of roller 7. Or it may be in the
form of a wide belt, with plate 22 running on each side thereof.
In the direction of travel 3,and behl~d baffle 5, belt 10 runs in the
feed plane over first conveyor element guide roller 13. A belt 18, running
over roller guides 16, 17, hinged to baffle 5, rests upon overlapped blanks 2
and is carried along therewith. The degree of overlap is thus retained as
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the objects m~ve onwards.
Baffle 5, which is vertically adjustable, is maunted in a holder 20
which is ada~ted to pivot about an axis 19 and`bears against a stop 21. ~affle
5 may be pushed upwardly against the force of a spring 14 having an adjust-
able pre-load.
When an accumulation 4 is formed in front of baffle 5, conveyor
belt 10 applies a force, in the vi~inity of roller 7, to lowermost blank 2.
Since this blank is relatively stiff, this conveying force is transferred
to sloping stop 6 of baffle 5. The resulting reaction force m~ves baffle
5 upwardly against the force of spring 14. The blank seized by conveyor
belt 10 in the vlrinity of roller 7 can then pass through gap 12. The blanks
lying above the aforesaid blank are still held back, assuming, of course,
that there is not too much friction between the blank being conveyed, and
the blank lying thereabove. This condition is u9~11y fulfilled in the case
of lac~uered blanks and no problems therefore arise. As soon as blank 2
seized by roller 7 on belt 10 leaves the said belt at the said roller,
transportation is a~fected entirely by front drive elements 10, 13 extending
as far as gap 12. At the moment when blank 2 leaves drive element 7,
the next blank is æ ized by conveyor belt 10 at roller 7, and the cycle
repeats itself.
By adjusting roller 7 and guide rollers 8, 9 tcwards ox away
from bafle 5, the extent to which blanks 2 overlap may be varied.
A sensor 15 can sense the amw nt o~ accumulation 4 and thereby
control the speed of the first and second conveyor elements~
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