AU612721B2 - Envelope feeder with adjustable constant overlap - Google Patents

Description

ililimWillili" WEL_ OP DATE 14/06/89 APPLN. I D 25344 88

PCT

INTERNATONALE A MEL A OJPDA 0 76 7 P NUMi ER PCT/CH88/00196 (51) Internationales Atenzeasiaiohn 4 C/H80 9 L(uo~shsPtn) O Eerpice~i (22) Internationales Anmeldedatun: tn) U S 19. Oktober 1988 (19.10.88) Veroffentlicht Mit internationalem Recherchenbericht.

(31) Prioritatsaktenzeichen: 4619/87-9 Mit geiinderten Anspriichen.

(32) Prioritaitsdatumn: 27. November 1987 (27.11,87) (33) Prioritatsland: CH (71)(72) Anmelder und Erfinder: STENZ, Reinhard [CH/ CR]; Brunnenwiesenstrasse 4, CH-8108 Dallikon

(CRH).

(74) Anwalt: ABATRON-PATENTBORO; Diggelmannstr.

22, CH-8047 Ztirich (CR).

(81) Bestimmungsstaaten: AT (eu 'opdisches Patent), AU, BE (europldisches Patent). BR, CR (europaiisches Patent), DE (europ~isches Patent), DK, Fl, FR (europdisches Patent), GB (europaisches Patent), IT (europ~isches Patent), JP, KP, KR, LU (europaisches Patent), (54) Title: ENVELOPE FEEDER WITH ADJUSTABLE CONSTANT OVERLAP (54) Bezeichnung: COUVERTANLEGER MIT EINSTELLBARER KONSTANTER ZWANGSSCHUPPUNG (57) Abstract An envelope feeder which can bc, used on virtually all existing printing machines without the need to synchronize the latter comprises a low-pressure chamber a perforated conveyor belt and an adjustable barrier An overlap with a very small overlap length is thereby achieved. The envelope feeder can therefore be used not only for small envelopes but also for those with very narrow flaps.

(57) Zusammienfassung In der vorliegenden Erfindung ist es gelungen, einen Couvertanleger zu schaffen, der praktisch fdr alle bestehenden Druckmaschinen einsetzbar ist, ohne dlass eine Synchronisction mit derselben notwending ist. Dabei gelang es unter Verwendung einer Unterdruckkammer einem gelochten Transportband und einer verstelibaren Barriere eine Zwangsschuppung mit einer sehr kleinen Schuppungsdistanz zu erreichen, dlass der Couvertanleger nicht nur f~r kleine Couverts eingesetzt werden kann, sondern auch fMr solche mit einem sehr schmalen Deckel (Signature of Declarant) THE COMMISSIONER OF PATENTS.

R. Stenz (IMPORTANT Cross out inapplicable words in above Form.) *014 524 U -1- The invention in question deals with the fundamental problem of how to feed envelopes for printing to a printing machine without an interruption in work or a misfeed coming about. If, for example a pile of envelopes is placed in front of a printing machine to be printed, then it will lift these envelopes individually in the printing cycle, e.g.

by means of a suction arm, and carry out the actual printing process.

In order to be able to place further envelopes from additional boxes, the machine would have to be switched off. In order to prevent this, one is forced to construct envelope feeders which continuously feed the printing machine with envelopes without the printing machine having to be interrupted.

5 According to the current state of the technology, there have up to now .i i been three different solutions of this problem, none of which was in a position to completely satisfy the problem.

1st variation: The printing machine and the envelope feeder are built 0 together as a single compact machine. There is thus no possibility of use of the envelope feeder on other printing machines.

2nd. Variation: Suction rods or suction plates take away the envelopes individually, which then have to go to the printing machine synchronously. The synchronous device existing on the market however only fits one printing machine available in the trade and is thus not compatible with others.

3rd. variation: A further envelope feeder is in fact partly compatible, but works with a rubber band, which results in a great deviation coming about in the overlap. In addition, this envelope feeder feeds the envelopes, as do all other feeders mentioned, in a longitudinal direction, i.e. the envelopes have the short side at the front and the flap is not at the front, but on the side. This means that this envelope feeder cannot be used for sheet-fed offset presses, which are intended for sheets of A3 format. The envelopes cannot be taken on by the overlap feeder of this printing machine, as with the width of the front smaller side is too small. This is above-all true for the C6 envelope.

The gap in the market mentioned here can now be filled with the invention in question, as an envelope feeder has been constructed which can transport the envelopes transversely, i.e. with the broader side in front. Thus an envelope feeder has been constructed which can be used for virtually all printing machines.

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*j 5 0 O I [I 1 [1 ft 11 In order to be able to transport the envelopes with the broad side forward and thus the flaps at the front, without the following envelopes sliding under the flap of the previous one when being pushed together, it was firstly necessary to solve the problem of being able to construct an envelope feeder which works very reliably with an overlap distance of, for example, 2 cm, and only has very low values of deviation. As shown in Fig. 1, this is above all, necessary for self-adhesive envelopes 1, which only have a very narrow flap 2 of about 2 cm. In Fig. 1 is shown what happens when the overlap distance, as shown in Fig. 1 is too large. The following envelopes 1 are then erroneously pushed under the flap 2 of the previous envelope during the formation of the storage pile. Fig. 1 d) shows how the envelopes come to lie on top of one another if, as in Fig. Ic), the overlap distance chosen is too small.

Tests have shown that such small overlap distances with only quite minimal deviations cannot be achieved with a rubber band in which the overlap distance is determined by the momentary frictional force.

The invention consists of the fact that the necessary precision and reliability are achieved with the help of a vacuum chamber 3 (cf. Fig.

a perforated conveyor belt 4 and an adjustable barrier 6.

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Fig. 2 a) shows how the bottom envelope of a pile of envelopes is sucked by the vacuum chamber 3. This results in it remaining on the conveyor belt 4 and being pulled away from the pile of envelopes as S the belt moves. As soon as the hindmost edge of the envelope has moved sufficiently to the right, the suctional effect can also be exerted on the second envelope from the bottom of the pile. This threshold situation is demonstrated exactly in Fig. 2 and in Fig. 2 S c) the second envelope from the bottom of the pile has already been affected by this suctional effect and is also going to the right S together with the bottom envelope, whereby the second envelope is displaced to right by the overlap distance 5 in comparison with the first envelope. When adjusting the vacuum, it is therefore important for the right strength to be used. If the vacuum is too high mbar), two envelopes will be pulled away at the same time, whereas in the case of less than half of this value flawless functioning is guaranteed.

i j c P4 -3- Fig. 2 shows clearly how the overlap distance 5 can be adjusted very simply, as it corresponds simultaneously to tie distance between the left edge of the vacuum chamber and the left edge of the envelope 1.

This overlap distance can be deliberately and precisely varied by the pile of envelopes being displaced to the left or the right. This can be carried out very simply with the adjustable barrier and the simultaneous stripper 6 (cf. Fig. as this barrier or stripper 6 can be adjusted to the left or right and then be fixed in any position.

In order to guarantee a certain security for the fact that not too many envelopes are pulled over to the right at the same time, the stripper 6 ease can also be adjusted as regards its height and again be fixed here in 15 any position. The task of the envelope feeder is now to form a storage pile of envelopes 8 (see Fig. 3) from which the overlap feeder of the printing machine can at any time remove envelopes to be printed. This storage pile 8 is achieved by further envelopes continuously being pushed in at the bottom of pile 8 and the pile thus o0 becoming larger if the envelopes are not removed at the top by the overlap feeder of the printing machine. In order that this storage pile cannot become too large, it is provided with a light barrier, so that envelope feeding can be controlled electronically in this way. In addition, a photo-cell can be installed in the refill pile 11, so that a signal is heard when refilling is necessary. The retaining roll 7 immediately in front of the storage pile 8 is also a part of this invention. It makes sure that any air is pressed out of the envelopes.

This additional can remov an old evil which has existed up to now in macIines.' As, soon as the excess air \kas pressed out of the envelopes 306- irn printing, the paper began to wobble and thus the printing was blurred and smeared. The above mentioned retaining roll 7 makes ure from the outset that no more air exists during the printing process and thus high printing precision comes about during the first run.

In order that he envelopes can even be pushed into the storage pile 8, it is necessary to make that in the overlap the following envelope is not above, but below the previous one, so that the following envelopes 1 are pushed into the bottom of the storage pile. This is achieved by the overlapped envelopes being turned in the same manner as this is carried out in envelope feeding machines already known. A second conveyor belt 10 is run at exactly the same speed underneath the first conveyor belt 4. The envelopes then come to rest on the second conveyor belt 10 underneath the first conveyor belt 4 after the first guide roll.

"I pLl~ '/11/ i s i_ i -4- Thus it can be stated that the invention in question has succeeded in constructing an envelope feeder which is easy to adjust and no longer has the disadvantages of existing machines, as it can be used for virtually all printing machines without synchronization with the printing machines being necessary and because it is possible, thanks to an exactly adjustable precise overlapping, to transport the envelopes on the conveyor belt with the broadside first.

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Claims (8)

1. An envelope feeder for a printing machine adapted to feed envelopes in the form of a stream of overlapped envelopes into a storage pile from a refill pile, characterised by an air permeable conveyor belt, a stripper above the conveyor belt to retain the refill pile, and a vacuum chamber below the belt, whereby the vacuum chamber is adapted to draw envelopes from the refill pile and hold them onto the belt for transport below the stripper to the storage pile, whereby the longitudinal position of the stripper in relation to the vacuum chamber can be varied so as to vary the degree of overlap S of the envelopes, further characterised by a transport arrangement .45 between the refill pile and storage pile to turn the stream of overlapped envelopes over, comprising the air permeable conveyor belt being led around a guide roller together with a second conveyor belt and the stream of overlapped envelopes being transferred to the second conveyor belt to convey the envelopes to the bottom of the storage pile. 0@4 @0e* i

2. Envelope feeder according to claim 1, characterized by the fact that the air-permeable conveyor belt is air permeable by means of perforations. O

3. Envelope feeder according to one of the claims 1 to 2, characterized by the fact that the distance of the stripper from the air-permeable conveyor belt is adjustable.

4. Envelope feeder according to one of the claims 1 to 3 further including an air extrusion element arranged above the second conveyor belt in front of the storage pile to extrude air from the envelopes in the stream of envelopes.

5. Envelope feeder according to claim 4, characterized by the fact that the air extrusion element is a rotatable retaining roller.

6. Envelope feeder according to one of the claims 1 to 5, further including a device for the supervision of the height of the storage pile and means to control the speed of the air-permeable conveyor belt depending upon the height of the storage pile.

7. Envelope feeder according to one of the claims 1 to 6, further including a device for the supervision of the height of the refill pile and means to emit a signal if this height drops below a pre- determined value. -6-

8. An envelope feeder substantially as hereinbefore described with reference to and as illustrated by the accompanying drawings. Dated this 16th day of April 1991 1 0 REINHARD STENZ By their Patent Attorneys COLLISON CO. o. eS S fteftf u