US3242784A - Apparatus for cutting strip material into sheets - Google Patents

Description

March 29, 1966 T. P. c. BREUERS APPARATUS FOR CUTTING STRIP MATERIAL INTO SHEETS Filed May 28, 1964 2 Sheets-Sheet 1 INVENTOR THEO Pt ERRE CHKETIEN BREUERS BY ATTORNEY March 29, 1966 T. P. c. BREUERS APPARATUS FOR CUTTING STRIP MATERIAL INTO SHEETS Filed May 28, 1964 2 Sheets-Sheet 2 INVENTOR TH E'O PIERRE CHRETIEN BREuERs BY gm ATTORNEY United States Patent 6 Claims. ((31. 83-210) The invention relates to an apparatus for cutting strip material into sheets.

According to the invention such apparatus comprises a strip holder, a blade which may be driven to sever the strip, a movable stop which is engageable by a strip of material fed from the strip holders, and which is arranged behind the blade at a distance therefrom equal to the length of strip to be severed, conveying means for feeding the strip against the stop to cause the formation of a loop in the strip ahead of the blade, and detecting means which are actuated when the loop is of a predetermined size and which thereupon drive the blade to sever the strip and actuate an arresting device for holding the strip stationary immediately ahead of the blade while simultaneously discontinuing or reducing the Ice ing means reaches the other extreme positon of its permitted displacement.

The apparatus according to the invention can be used as an independent apparatus; it can also be used in combination with an apparatus arranged behind it, which treats the lengths of severed strip, such as a diazo printer, an offset machine, and the like. In the last-mentioned case it may be attractive, in order to achieve proper synchronism between the operation of the cutting apparatus and that of the apparatus treating the sheets, to remove the stop for arresting the strip by means of an impulse which is generated by the apparatus treating the sheets.

If the cutting apparatus is combined with a copying device, the said impulse may, for example, be generated by a response member (switch, photocell, and the like),

a which responds to the passage of the leading edge of the image-bearing material to be copied photoprint tracing,

offset master plate, and the like) when the latter is fed contact between the conveying means and the strip, and

an accumulator roller over which the strip passes between the strip holder and the arresting device, which roller is displaceable vertically as the total length of strip between the strip holder and the conveying means varies.

Known apparatuses of this kind (see for example British patent specification 795,245) function in a reliable manner when they are used for cutting somewhat elastic material (metal strip and the like) because in that case the loop which is formed in the strip can be elastically flattened after the blade has returned to its initial position, the newly formed leading edge of the strip moving underneath the blade. Difficulty, however, arises when material is handled which is extremely thin and/or limp and in which, upon the formation of the loop, bends tend to be formed, which prevent elastic flattening. Such difiiculty is particularly acute when the web of material is fed through the apparatus with great speed and the lengths to be cut off are relatively small.

It is the object of the invention to improve the known apparatus in such a manner that also thin and/or limp material (such as paper of 40 g./m. can be cut into relatively small sheets (for example of size DIN A5) with great speed (for example 40 metres/min).

By the accumulator roller it is ensured that whenever the contact between the conveying means and the strip is reduced or discontinued, the strip is flattened under the influence of the weight of the roller, so that' the loop in the strip has disappeared When the blade returns to its initial position. At the same time the arresting device prevents the leading edge of the strip from being pulled away from the blade by the weight of the roller.

As the strip is unwound from the strip holder, the tensile forces which are thus set up in the strip may be so great that the strip is torn. Slip may also occur between the strip and the conveying means. Although this slip has no influence on the accuracy with which the sheets are cut off, it might damage the surface of the strip, while it might also have an adverse eliect upon the operating speed of the apparatus. According to the invention these disadvantages can be avoided by providing the apparatus with a driving mechanism for withdrawing strip from the strip holder and switches in the path of the displaceable guiding means, by means of which switches the driving mechanism is respectively switched off when the displaceable guiding means reaches one extreme position and switched on when the said guidinto the copying unit.

The impulse with which the stop for arresting the strip is removed can at the same time be used for reactuating the conveying means after the severing operation. If, however, owing to one cause or another, the sheet already severed fails to leave the cutting apparatus, still a fresh part of the strip will be fed underneath the blade, which will then get between the guiding means together with the sheet cut off. Serious trouble may ensue from this. Such trouble can be avoided by providing the apparatus with a response member (electric switch, photocell, and the like), which responds to the movement of the severed sheet past the stop and will thereupon give out an impulse, by means of'which the conveying means are re-actuated after the severing of the strip. Thus it is ensured that the strip is fed further only when it has been found that the sheet already cut off is leaving the apparatus.

The invention will now be elucidated more fully, and by way of example only with reference to the accompanying drawings.

In these drawings:

' FIGURE 1 s a diagrammatic plan of la diazo printer, which includes a cutting apparatus according to the invention,

FIGURE 2 is a diagrammatic longitudinal section of the same apparatus along the line Ila-II in FIG- URE l, and

FIGURE 3 represents the wiring diagram of the electric control circuit of the apparatus according to FIG- URES 1 and 2.

Referring to FIGURES 1 and. 2, the apparatus is built up between two vertical frame plates 1 and 2, which are rigidly held together by connecting rods 3, 4, 5, and 6. The exposure unit of the apparatus, which is of a construction known per se, comprises a rotating exposure cylinder 7, within which a tubular copying lamp 8 is mounted. Arranged around the cylinder 7 is a system of conveying belts 9, which is further guided over rollers 10, 11, 12, and 13. Roller 11 is movably supported in slots in the frame plates 1 and 2; helical springs 14 pull at .the trunnions of this roll and thus keep the conveying belts 9 tensioned. Roller 10, which is coupled to the adjustable driving mechanism (not shown) of the apparatus, drives the belts 9, and the latter in turn drive the exposure cylinder 7.

The exposure unit further comprises conveyer rollers 15, 16, 17, 18, and 19, which are driven (in a conventional manner not shown) of the same speed as the cylinder 7, and stationarily mounted guide plates 20, 21, 22, 23, and 24. At the feeding side of the exposure unit an original-feeding mechanism is mounted, which comprises a table 26 and a guide plate 27.

Against the underside of table 26 is mounted a conveyer roller 28, which is coupled to the driving mechanism of the apparatus and those surface passes through a slot in table 26. Above guide plate 27 is located a rod 29, which is rotatably supported in the frame plates of the apparatus. Fastened to this rod 29 are brackets 30 and 31, in which a pressure roll 32 is rotatably supported. Also fastened to the rod 29 are a number of stops 33. At one of its ends the bracket 30 is coupled to the movable core of an electromagnet 34 and at its other end it is coupled to a helical tension spring 35 which is fastened to the frame. When the electromagnet 34 is not energized, the original-feeding mechanism is in its position of rest (see FIGURE 2), in which the stops 33 project through openings in the plate 27 and rest on the table 26, while the rollers 28 and 32 are not in contact with each other. When electromagnet 34 is energized, its core is moved, and the bracket 30, with the stops 33, pivots about the rod 29 so that the stops 33 move away from the table 26, and the pressure roller 32, via an opening in the plate 27, is forced against the conveyor roller 28. Further a tumbler switch 36 is secured to the connecting rod 6, the lever of said switch projecting through an opening in plate 27.

The cutting apparatus comprises a conveyor roller 41, which is directly coupled to the driving mechanism of the apparatus, and a conveyor roller 42, which may be coupled to the driving mechanism via a conventional electromagnetic coupling mechanism not shown in FIG- URES 1 or 2.

Guide rollers 43 and 44 are rotatably supported in the frame plates of the apparatus, while a displaceable roller 45 is supported so as to be rotatable and vertically movable between rails 46 and 47, which are fastened to frame plate 1, and similar rails 48 and 49, which is fastened to frame plate 2. The displaceable roller 45 cooperates with a pair of electric switches 50 and 51, which are secured to the frame plate 1 near the ends of rail 47, at the limits of permitted displacement of the roller 45.

A rod 52 is rotatably supported in the frame plates 1 and 2. Secured to the rod 52 near its ends are brackets 53, in which a disk roll 54' is rotatably supported. Fur thermore a number of stops 55 are secured on the rod 52 at intervals. The bracket 53 mounted near the frame plate 1 is coupled at its end to the movable core of an electromagnet 56 and to a helical tension spring 57 fastened to the frame plate 1. When the electromagnet 56 is not energized, the rod 52 takes a position in which the stops 55 rest on a guide plate 58 and the rollers 41 and 54 are not in contact with each other (see FIGURE 2). When the electromagnet 56 is energized, the movement of the core of the magnet causes a movement of the rod 52, so that the stops 55 move away from plate 58 and the roller 54 is forced against the roller 41. Fastened to the connecting rod is a tumbler switch 59 the lever of which projects through an opening in the guide plate 58.

Fastened to the frame plate 1 is a lead screw 60, which is rotatably mounted in the bearings 61 and 62 attached to the frame plate 1 and which is provided with a handwheel 63 protruding from the frame. A rod 64, parallel to, and level with, the leadscrew 60 is secured to the frame plate 2 with the aid of supports 65 and 66. Screw 60' and rod 64 support the cutting unit of the apparatus, which unit is built up between vertical frame plates 67 and 68, which are rigidly held together by connecting rods 69, 70, 71 and 72. The frame plate 67 is provided with non-rotating nuts 73 and 74, through which the leadscrew 60 is threaded, and the frame plate 68 is provided with sleeves 75 and 76, which are slidably mounted on the rod 64. Thus, the cutting unit is supported by the leadscrew 60 and the rod 64 and can be moved by rotation of the handwheel 63.

The cutting unit comprises a fixed blade 77 which is mounted between the frame plates 67 and 68, and a blade 78 which is vertically movable between the frame plates 67 and 68. The blade 78 is carried by an L-section bar 79, which is in turn supported at its ends by brackets 80. The brackets 80 are secured to respective trunnions 81, which are movably supported in vertical slots in the frame plates 67 and 68 respectively. The parts of the trunnions S1 projecting beyond the frame plates are connected in a conventional manner to the vertically movable cores of electromagnets 82 and 83, and to vertically disposed helical springs 84. Horizontally disposed tension springs 85, which engage the brackets 80, provide a force urging the blade 78 constantly into contact with the blade 77.

A driving roller 86, which is coupled to the driving mechanism of the apparatus and the rod 87, are respectively rotatably supported in the frame plates 67 and 68. The rod 87 carries near its ends, and adjacent the frame plates 67, 68 respectively brackets 88, 89. The brackets 88, 89 are rigidly connected by means of a tie bar 90. A pressure roller 91 is rotatably supported in the brackets 88 and 89, and to the tie bar are fastened a number of pressure members 92 which act as brake blocks. The bracket 88 is coupled to the movable core of electromagnet 93, and to a helical tension 95.

When the electromagnet 93, is not energized, under the influence of the springs 95 the brackets 88 and 89 take a position (see FIGURE 2) in which the pressure roller 91 is forced against the driving roll 86 via an opening in a fixed guide plate 96. When the electromagnet 93 is energized, it moves the bracket 88, in consequence of which the pressure roller 91 moves away from the driving roller 86 and the pressure members 92 are forced against blade 77 via openings in a fixed guide plate 97. An electric switch 98 is secured to the connecting rod 72. Switch 98 is provided with a switch lever 99 which acts as a detecting member.

Between the connecting rod 4 and the table 26 a number of juxtaposed flexible guiding belts 100 are tensioned at intervals, said belts 100 being guided over the connecting rod 69 and the rod 87. Between the connecting rod 3 and the guide plate 58 similar belts 101 are tensioned, said belts 100 being guided over the connecting rods 71 and 70.

A supply roll of light-sensitive paper 102 is mounted on a shaft 103; the paper strip 112 running from the supply roll 102 is subsequently guided over the rollers 44, 42, 45, and 43 respectively and put in readiness with its leading edge clamped between the nip of the rollers 86 and 91.

The operation of the apparatus will now be described, with additional reference to FIGURE 3.

After the driving mechanism of the apparatus has been switched on, the cylinder 7 and the driving rollers 10, 18, 28, 41, and 86 rotate as indicated by arrows (see FIG- URE 2).

By the driving action of the roller 86, strip 112 is moved over the guide plate 96, beneath switch lever 99, between the blades '77 and 78 and between the guiding belts 100 and 101, until the leading edge of the strip 112 is arrested by the stops 55. Owing to the continued supply of paper by the rollers 86 and 91 the paper strip 112 subsequently forms a loop of its point of entry between the guide plates 96, 97, thereby lifting the switch lever 99 and closing the switch 98. Via switch 98 a relay 104 is then energized which closes its contacts 104a and 1041? (see FIGURE 3). Via contact 104a and resistor 105 a relay 106 is energized. The relay contact 106a of relay 106 is closed and via this contact the electromagnets 82 and 83 are energized. The cores of the electromagnets 82, 83 are then moved and blade 78 is moved downwardly, cutting the strip 112 into a sheet the length of which is equal to. the distance between the blade 78 and the stops 55. By turning the handwheel 63, by means of which, as described above, the cutting unit can be moved, this length can be preset to a desired value.

Via conact 104a and RC circuit comprising a resistor 107, and a capacitor 108 is simultaneously connected to the electrical supply. A relay 109 is connected across the capacitor 108. The excitation of the relay 109 is, however, delayed due to the said R-C circuit so that the contact 109a of relay 109 is closed later than the contact 106a of relay 106. Via contact 109a of relay 109 the electromagnet 93 is energized, causing the brackets 88 and 89 to swivel downwardly about the rod 97. The pressure members 92 then force the strip 112 firmly against the blade 77, and simultaneously the strip 112 is released, since the rollers 86 and 91 are no longer being forced against each other. By the weight of the displaceable roller 45 the loop which formed in the strip 112 is flattened and the switch lever 99 returns to its initial position. The switch 98 is non-opened again, but the relay 104 (and thus also the electromagnets 82, 83, and 93) remains energized, through the relay via contact 104b and a contact of the'switch 59 'which are connected in parallel with the switch 98.

If an image bearing sheet to be copied is subsequently fed over table 26 into the apparatus, its leading edge operates the lever of tumbler switch 36 at the moment when this edge impinges against the stops 33. Via the switch 36 electromagnets 34 and 56 are energized, in consequence of which the stops 33 and 55 are lifted, and the rollers 41 and 54 on the one hand and the rollers 28 and 32 on the other hand, are forced into contact with each other. The image-bearing sheet and the severed light-sensitive strip 112 are then gripped by the pairs of rollers 28, 32 and 41, 54 respectively and brought together between the rollers 13 and 15, and are subsequently fed between the cylinder 7 and the conveyor belts 9 around the copying lamp 8 to be exposed. After exposure the two sheets are separated (with the aid of conventional means not shown in the drawing). The light-sensitive sheet then moves between the roller 19 and the conveyor belts 9 to the guide plate 24, while the image-bearing sheet is fed between guide plate 20 and the cylinder 7 between the rollers 15 and 16, the guide plates 21 and 22, and the rollers 17 and 18, to the guide plate 23.

During the movement described above the light-sensitive sheet will have reversed tumbler switch 59 with its leading edge. The contact of the switch 59 is thus opened, in consequence of which the excitation of relay 104, and thus also the excitation of the relays 106 and 109, is interrupted. Owing to the opening of contact 106a the excitation of the electromagnets 82, 83 is interrupted, in consequence of which the helical springs 84 return the blade 78 to its initial position. After a delay caused by the discharge of the capacitor 108 through the coil of relay 109, the contact 109a also is opened, so that the excitation of the electromagnet 93 is interrupted. The helical spring 95 then returns the pressure members 92 and the roller 91 to their initial positions. The strip 112 is then started again and its leading edge is fed between the guiding belts 100 and 101, as previously described.

A gap is formed between the leading edge of strip 112 and the trailing edge of the previously severed portion] of the strip 112. This gap arises due to the delayed reaction of relay 109. By an appropriate choice of the resistor 107 and the capacitor 108 suitable values of the delay introduced, and therefore the size of the gap formed, can be selected.

When the trailing edge of the image-bearing sheet fed to the cylinder 7 has moved past switch 36, this switch is opened again, in consequence of which the excitation of the electromaguets 34 and 35 is interrupted. Under the influence of the helical springs 35 and 57 the rollers 32 and 54 and the stops 33 and 55 then return to their initial positions. The leading edge of the strip 112 is now again arrested by the stops 33; thus again a loop is formed in the strip 112, and the sequence described above repeats itself.

As the strip 112 is fed through the apparatus the displaceable roller 45 is moved upwardly between the rails 46, 47 and 48, 49, until eventually it has moved until it operates the end switch 50. Via switch 50 a relay is energized, which then closes its contacts 110a and 11%. Via contact 110a the electromagnetic coupling of roller 42 (indicated diagrammatically as 111 in FIGURE 3) is energized, and the roller 42 is coupled to the driving mechanism of the apparatus. The roller 42 then starts rotating, so that material is then unwound from the supply roll 102. The displaceable roller 45 begins to move downwardly as the supply roll 102 is unwound. The switch 50 is thus opened again, but the relay 110 remains energized via the switch 51 and the closed contact 11% which are connected in parallel with the switch 50. When the roller 45 has sunk until it operates the switch 51, the excitation of the relay 110 is interrupted and owing to the opening of contact 110a the excitation of the electromagnetic coupling 111 is also interrupted. The roller 42 therefore stops and no fresh material is unwound from the supply roll 102 until the displaceable roller 45 again attains its highest position and switch 50 is closed again.

Thus in the apparatus described above, whenever an image-bearing sheet is fed into the apparatus, it is combined with a sheet of light-sensitive material from the strip 112 lying in readiness and fed through the exposure unit of the apparatus. The feeding speed, by which the rate of exposure is determined, is adapted to the trans parency of the image-bearing sheet and the light-sensitiveness of the strip 112. Although the feeding speed will thus have to vary from case to case, the variations thus occurring do not affect the accuracy with which the sheets are cut oil.

In the apparatus shown in the drawing the cutting device is combined with an exposure apparatus in which each image-bearing sheet copied only once each time. It is of course also possible to combine it with a copying device in which an image-bearing sheet is automatically copied several times in succession. In such a case the control circuit would be constructed in such a way that the response member which controls the feeding of the severed strip responds whenever the image-bearing sheet has passed through the copying unit and enters the copying unit again for a further copying cycle.

What I claim is:

1. Apparatus for cutting strip material into sheets, said apparatus comprising a strip holder, a blade which may be driven to sever the strip, a movable stop which is engageable by a strip of material fed from the strip holder, and which is arranged behind the blade and at a distance therefrom equal to the length of strip to be severed, conveying means for feeding the strip against the stop, to cause the formation of a loop in the strip ahead of the blade, detecting means which are acutated when the loop is of a predetermined size and which thereupon drive the blade to sever the strip and actuate an arresting device for holding the strip stationary immediately ahead of the blade while simultaneously discontinuing or reducing the contact between the conveying means and the strip, and an accumulator roller over which the strip passes between the strip holder and the arresting device, which roller is displaceable vertically as the total length of strip between the strip holder and the conveying means varies.

2. Apparatus according to claim 1 comprising a driving mechanism for withdrawing strip from the strip holder and switches in the path of the displaceable guiding means, by means of which switches the driving mechanism is respectively switched off when the displaceable guiding means reaches one extreme position and switched on when the said guiding means reaches the other extreme position, of its permitted displacement.

3. Apparatus according to claim 1 in combination with apparatus for treating the lengths of severed strip arranged behind it, comprising means for removing the stop with the aid of an impulse which is generated by said apparatus for treating the sheets.

4. Apparatus according to claim 3, wherein the said ap paratus for treating the sheets is a copying machine and the said impulse is generated by the actuation of a response member which is actuated when the leading edge of the image-bearing material to be copied is fed into the copying machine.

5. Apparatus according to claim 1 including a response member which responds to the movement of a severed sheet past the movable stop by producing an impulse by means of which the conveying means are reactuated after the severing of the strip.

6. Apparatus for cutting strip material into sheets, said apparatus comprising a strip holder, a blade which may be driven to sever the strip, a movable stop which is engageable by a strip of material fed from the strip holder, and which is arranged behind the blade and at a distance therefrom equal to the length of strip to be severedyconveying means for feeding the strip against the stop, to cause the formation of a loop in the strip ahead of the blade, detecting means which are actuated when the loop is of a predetermined size and which thereupon drive the blade to sever the strip and actuate an arresting device for holding the strip stationary immediately ahead of the blade While simultaneously discontinuing or reducing the contact between the conveying means and the strip, an accumulator roller over which the strip passes between the strip holder and the arresting device, which roller is displaceable vertically as the total length of strip.

8 between the strip holder and the conveying means varies, a driving mechanism for withdrawing strip from the strip holder, switches in the path of the displaceable guiding means, by means of which switches the driving mechanism 5' is respectively switched oif when the displaceable guiding means reaches one extreme position and switched on when the said guiding means reaches the other extreme position, of its permitted displacement, and a response member which responds to the movement of a severed 1O sheet past the movable stop by producing an impulse by means of which the conveying means are reactuated after the severing of the strip.

15 References Cited by the Examiner UNITED STATES PATENTS 2,161,123 6/1939 Avery 83-21O X 2,480,781 8/1949 Simpson 83-209 X 20 2,710,565 6/1955 Schroeder 83-65 X 3,182,539 5/1965 Williams 83-639 X 3,185,025 5/1965 Pfafr" et a1. 83917 X 25 FOREIGN PATENTS 795,245 5/1958' Great Britain.

WILLIAM W. DYER, JR., Primary Examiner.

3 J. M.. MEISTER, Assistant Examiner.

Claims (1)

1. APPARATUS FOR CUTTING STRIP MATERIAL INTO SHEETS, SAID APPARATUS COMPRISING A STRIP HOLDER, A BLADE WHICH MAY BE DRIVEN TO SEVER THE STRIP, A MOVABLE STOP WHICH IS ENGAGEABLE BY A STRIP OF MATERIAL FED FROM THE STRIP HOLDER, AND WHICH IS ARRANGED BEHIND THE BLADE AND AT A DISTANCE THEREFROM EQUAL TO THE LENGTH OF STRIP TO BE SEVERED, CONVEYING MEANS FOR FEEDING THE STRIP AGAINST THE STOP, TO CAUSE THE FORMATION OF A LOOP IN THE STRIP AHEAD OF THE BLADE, DETECTING MEANS WHICH ARE ACTUATED WHEN THE LOOP IS OF A PREDETERMINED SIZE AND WHICH THEREUPON DRIVE THE BLADE TO SEVER THE STRIP AND ACTUATE AN ARRESTING DEVICE FOR HOLDING THE STRIP STATIONARY IMMEDIATELY AHEAD OF THE BLADE WHILE SIMULTANEOUSLY DISCONTINUING OR REDUCING THE CONTACT BETWEEN THE CONVEYING MEANS AND THE STRIP, AND AN ACCUMULATOR ROLLER OVER WHICH THE STRIP PASSES BETWEEN THE STRIP HOLDER AND THE ARRESTING DEVICE, WHICH ROLLER IS DISPLACEABLE VERTICALLY AS THE TOTAL LENGTH OF STRIP BETWEEN THE STRIP HOLDER AND THE CONVEYING MEANS VARIES.

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