JPS629498B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for feeding continuous sheets of printed packaging material to an automatic cutter for producing printed unit packaging sheets. This method is particularly applicable to the operation of a device for producing unit packaging sheets in a cigarette packaging machine, more particularly in a cigarette packaging machine producing cigarette packs of the so-called "soft" or "american" type, in the case of which cigarette packaging machines rectangular Precisely a printed sheet of wrapping paper is used, and the printed unit wrapping sheet is cut from a continuous sheet unwound from a roll. The continuous sheet is preprinted for successive repetitions of the same print.

In reality, incomplete printing occurs during the continuous printing process for producing printed packaging sheets. The imperfections in the continuous sheet must be removed and the sheet must necessarily be continued in order to maintain the correct printing process.
Apart from printing imperfections, sheets develop defects that require removal and continuation.

As a result, continuous printing processes create disadvantages that lead to increased costs. Moreover, the presence of continuations in the continuous sheet during use can lead to other disadvantages such as jamming of the sheet while passing through the cutter.

The method according to the invention proposes the following. (a) During use of a continuous sheet of printed packaging material, the imperfection is not previously removed and is simply marked with an initial spot mark (a form applied for detection by a detector); mark) and a visible termination mark.

(b) A roll of printed continuous sheets is placed in a packaging machine having an automatic roll changeover and continuation device.

(c) When the starting spot mark of the incomplete part is detected, the automatic switching device interrupts the supply of the incomplete sheet and switches to the spare roll.

(d) Meanwhile, the worker manually removes the imperfection that has a visible end spot mark on the edge, and after the worker has removed the imperfection, removes the leading edge of the continuous sheet. Insert again into automatic switching and continuation device.

In this way, by feeding continuous sheets of printed packaging material to the automatic cutter, imperfections such as printing defects can be removed when feeding continuous sheets, and patterns can be removed during the continuous printing process to create continuous sheets. It is no longer necessary to take special care to ensure that the images are printed accurately and continuously, and the cost increase of the continuous printing process can be prevented.

The present invention will be described in detail below based on an embodiment shown in the drawings. is shown.

In the drawings, symbols N1 and N2 indicate the first roll B.
Two sheets of packaging material are unwound from the first and second rolls B2, respectively, these sheets N1 and N2 forming buffer loops A1 and A2, respectively, inside the box 14. Each box 14 has an opposite light emitter 20,
Detectors 16, 17, 18, 19 are provided which cooperate with 21, 22, 23 to detect the length of the loops A1, A2. The parts emerging from the loops A1, A2 converge towards a single transverse cutter 26, 27 and are suitably guided within a converging duct which guides in a Y-shape upstream of this cutter 26,27. Along the path of each sheet N1, N2, optical detectors 125, 22 detect the presence of each sheet.
5. A pair of supply rollers 11, 12 and manual cutters 54, 55 are provided for neatly cutting the leading edge of sheet N1 or N2 coming from roll B1 or B2, respectively. Each buffer loop A along the path of each seat N1, N2
1, A2 are provided with detectors 56, 57 for indicating the depletion of each roll B1, B2, which detectors 56, 57 are constructed, for example, in the form of photosensitive devices, transparent or inverted.

Assuming that the roll to be rewound is roll B2 and that roller B1 is the reserve roll, the roll changeover is performed as follows.

Taking into account that the sheets of rolls B1, B2 are preprinted, the manual cutting of the leading edge of the preliminary roll sheet N1 must be carried out at a predetermined cutting line. This leading edge is then connected to each supply roller 1.
1 and 12 and the sheet is manually advanced so that the cut leading edge passes past the spot-read detector 125. By depressing the operating pushbutton, an irregular cycle of the step motor is started which drives the pair of feed rollers 11, 12 for sheet N1 of reserve roll B1. This cycle is
In order to place the front edge of the preliminary sheet N1 approximately from the cutting lines of the cutters 26 and 27 to the interference area zi at the number of steps "n", after detecting the reference spot of the sheet by the optical sensor 125, the step motor is activated. is performed at a "start-stop" speed to allow multiple step movements.

If the roll to be rewound (roll B2) is emptied or the detector detects a starting spot indicating an incomplete part in the sheet N2, the last possible unit sheet F is determined by the buffer sheet N2 of its loop A2. After the end of the cutting cycle, when a switching command is issued by a control circuit operated by a suitable detector, the inactive time of the feed rollers 11, 12 associated with sheet N2 begins.

During this period, the stop signal for the cutting cycle of cutters 26, 27 initiates an irregular cycle of the motor controlling feed rollers 11, 12 for sheet N2. This irregular cycle reversely rotates the rollers 11 and 12 in a direction opposite to the feeding direction of the sheet N2 so as to pull out the final end of the sheet N2 on the roll B2 from the cutter 26. At the same time or with a suitable time delay, spare sheet N
A step motor that drives supply rollers 11 and 12 related to sheet N1 feeds the leading edge of sheet N1 to cutter 2.
Another irregular cycle is started to coincide with the cut lines 6 and 27, and sheet N1 is thus advanced in the "n" steps described above. In this way, when the next start signal arrives, the spare sheet N1 is left in the normally fed state.

For accurate operation of the equipment, imperfections (print defects) in the sheet material are marked with start and end spot marks, which are used to mark the winding of the sheet material to form a roll. It is done on occasion. The starting end spot mark (starting end in the redirection direction of the sheet roll) is
It may be in the form of a hole or cutout or in the form of a magnetic or electrically inductive spot, while the end spot mark may be a visible mark used to attract and detect the attention of the operator. The detection devices for detecting the start spot of the imperfection correspondingly include auxiliary detectors 156 (for sheet N1) and 147.
(for sheet N2), these detectors sense either holes, magnetic spots or electrically inductive spots in the sheet. In this manner, when the auxiliary detector 156 or 157 detects the starting spot mark on the sheet being rewound, a switching command is automatically given to the device that switches the rolls. In the meantime, the operator can manually remove the imperfections and reposition each sheet again for the next switching operation, which is useful for detecting imperfections in pre-queued sheets or spare sheets, etc. It is carried out based on

The final depletion of roll B1 or B2, indicated by the appropriate depletion spot mark on each sheet, is determined by the appropriate detectors 56 (for sheet N1) and 57.
(for sheet N2) and these detectors command a changeover to the spare roll to replace the empty roll with a full roll as described above.

It is believed that the present invention is clearly understood from the above description. Changes in construction and operational details may be made without departing from the spirit of the invention, and the invention is therefore not limited to the embodiments.
It is to be interpreted to the fullest extent by the literal meaning of the claims.

[Brief explanation of the drawing]

The drawing is a schematic side view of a feeding device for continuous sheets of packaging material according to the invention. B1, B2... Roll, N1, N2... Continuous sheet, 11, 12... Supply roller, 14... Box, 26, 27... Cutter, 156, 157
……Detector.

Claims (1)

[Claims] 1 at least two rolls B1, B2 of packaging material in the form of continuous sheets N1, N2 and spot marks provided on the continuous sheet for unwinding the continuous sheet from either of these rolls B1, B2; Responsive automatic switching and continuation device 1
4,58, in a method for feeding a continuous sheet of printed packaging material to an automatic cutter for producing printed unit packaging sheets, particularly adapted for use in the operation of a cigarette packaging machine, to each roll. During winding of a continuous sheet of packaging material, imperfections in the continuous sheet are marked with a starting end spot mark and an end spot mark visible to the operator, and the automatic switching and continuation device is provided with auxiliary detectors 156, 157. and the auxiliary detector detects the start spot mark and a change to the other roll is automatically made based on the detection of the start spot mark on the continuous sheet being rewound from this one roll. The printed packaging is characterized in that the automatic switching and continuation device is controlled, and after the detected incomplete portion of the continuous sheet is manually removed, the continuous sheet is inserted into the automatic switching and continuation device again. How to feed continuous sheets of material to an automatic cutter.