US 3697062 A
A machine is used for the zigzag folding of sheets, particularly paper sheets, in predetermined sizes. The machine has a table carrying the sheets to be folded and a carriage reciprocating above the table. A swing carried by the carriage carries a driven pair of folding rollers which are actuated in such manner that when the carriage moves forwardly one of the rollers table against the ta and when the carriage moves rearwardly the other one of the rollers presses against the table.
Description (OCR text may contain errors)
United States Patent 1 1 3,697,062 Mones et al. Oct. 10, 1972  MACHINE FOR THE ZIGZAG 2,037,561 4/1936 Blosser et al ..270/69 X FOLDING OF SHEETS 3,570,841 3/1971 Rettig ..270/64 2,761,678 9/1956 Conn et al. ..270/79  Invemms' Ham Am Markweg 2,921,786 1/1960 Deichmann et a] ..270/31 5601 6mm; Walter 611 799 Schulze ..270/30 Breldenhoferstrasse 30, 13-5657 2,276,854 3/1942 Margadant ..270/83 Haan, both of Germany 22 i D 3, 19 9 Primary Examiner-Robert W. Michell Attorney-Richards & Geier  Appl. No.: 881,818
 ABSTRACT  Foreign Application Priority Data A machine is used for the zigzag folding of sheets, particularly paper sheets, in predetermined sizes. The I968 Germany 18 12 5570 machine has a table carrying the sheets to be folded and a carriage reciprocating above the table. A swing  US. Cl ..270/30, 270/79 carried by the carriage carries a driven pair of folding  111i. Cl. ..B65h 29/46 rollers which are actuated in Such manner that when  Field of Search ..270/30, 31, 79, 52.5, 61, 64, the carriage moves forwardly one f the rollers table 270/69 against the ta and when the carriage moves rearwardly the other one of the rollers presses against the table.  References Cited 4 Claims, 16 Drawing Figures UNITED STATES PATENTS 8,005 4/1851 Boots ..270/ 30 PATENT Enact 10 m2 SHEET 1 BF 6 INVENTORS; H. Hones M M Hone BYI AT-royLms mwml PATENTEDncT 10 I972 SHEET 3 [1F 6 lll:
INVENTORS: H. Manes M4 W. Mones ATTOVLNE9$ PATENTEUucT 1 0 1972- suan u 0F 6 INVENTORS! H. M00850. NOD65 BY: 1 GULJAOLAU -5- PATENTEDnm 1 I912 3.697; 062 SHEET 6 OF 6 lwvliw'rtms: H. Manes m N. None;
AT ran-MESS THE ZIGZAG FOLDING OF SHEETS This invention relates to a machine for the zigzag folding of sheets, particularly paper sheets in predetermined shapes, the machine having a table serving as a support for the sheet being folded.
Machines are known which fold small sheets crosswise. There are also machines using so-called driver sheets for folding in zigzag manner maps, drawings or the like. The operations of these machines are very limited. They can not be adjusted to sheets of other sizes or such adjustment can be carried out only with great difficulty. Furthermore, it is difficult to produce on these machines precise and sharp-edged folds since, as is known, it is not possible to fold with sufficient sharpness paper of different thickness and types around a driven member even if that member has a very sharp edge.
An object of the present invention is to improve prior constructions.
Another object is the provision of a machine of simple structure which operates completely automatically for the zigzag folding of sheets, particularly paper sheets, which can be set to any size of sheet to be folded and which will produce sharp folding edges.
Other objects of. the present invention will become apparent in the course of the following specification.
In the accomplishment of the objectives of the present invention it was found desirable to provide a carriage moving back and forth above the table for the sheets being folded. A driven pair of folding rollers carried by a swing is so mounted in the carriage that when the carriage moves forward one roller presses against the table and when the carriage moves back the other roller presses against the table.
In accordance with the present invention the drive is MACHINE FOR advantageously so constructed that the wheels actuat-,
ing the folding rollers mesh with a rack which is moved longitudinally to provide paper entry relatively to the wheels driving the rollers. Then the rack stands still and is used for actuating the roller driving wheels during the movement of the carriage.
Furthermore, in accordance with the present inventionthe device is advantageously so constructed that separate racks are provided on opposite sides of the carriage, one of the racks extending below the roller driving wheels while the other rack is located above the roller driving wheels.
The present invention also provides an effective construction by using a crane rod drive for the tilting movement of the swing and the longitudinal movement of the carriage.
An advantageous feature of the present invention consists in the provision of a brake disc for at least one of the folding rollers.
Furthermore, the present invention advantageously provides pressure rollers in front of the folding rollers, at least one of the pressure rollers being movable into a raised position.
To comply with the German Industry Norm DIN824 requiring triangular fold, the present invention provides at the rear end of the table a separate plate section which is movable up and down and which forms a triangular end portion of the incoming end of the sheet.
For this construction it is advantageouswhen in accordance with the present invention a ledge is provided under this section which can clamp the folded sheet end and which is movable up into the clamping position.
To produce transverse folds the present invention provides shafts located at the outer sides of the table and provided with folding wheels.
The present invention provides an effective construction of the 'table by supplying it with suction openings, known as such, for holding the incoming end of the sheet.
Finally according to the present invention it is advantageous to make the carriage of two slide rings joined by a transverse axle and guided on rails.
The described construction provides a completely automatically operating machine for the zigzag folding of sheets, particularly paper sheets. li is merely necessary to push the sheet to be folded into the machine. The size of the zigzag folds which are to be produced can be set as required. The sheet passes the pair of folding rollers carried upon a swing in a direction opposed to their direction of rotation in such manner that during the forward movement of the carriage one folding roller presses against the sheet and produces a sharp folding edge, while during the return movement of the carriage the other roller presses against the table and also produces a sharp folding edge. Thus the paper is advantageously folded about itself without any intermediate body, whereby the location of the folds is attained by a precise conformity of the movement of the paper with the movements of the reciprocating carriage. Papers of different thickness and makes can be effectively provided with sharp folding edges. When the first paper layer is placed the wheels driving the folding rollers mesh with the longitudinally movable rack; when the rack stands still the roller driving wheels rotate upon it during the movement of the carriage. These gear wheels are of the same size and their pitch diameter is equal to the roller diameter, so that the rollers rotate with a circumferential speed which corresponds precisely to the rolling speed of the rollers upon the table. This results in the feature that the rolling movement is exactly equal to the path of the carriage. To assure that the direction of rotation of the rollers will remain unchanged, separate racks are provided upon the two sides of the carriage. When the carriage moves forward, the driving wheels rotate upon the rack located below them, while during the return movement the driving wheels rotate upon the rack located above them. The longitudinal movement and the tipping movement of the swing take place advantageously through a crank rod drive. Due to this drive, any small intermediate fold can be produced. To make a small fold the cranks carry out only a part of a complete rotation, whereupon they change their direction of rotation. When a dead point is reached or when the direction of rotation is changed, the carriage stands still and a swinging movement of the rod takes place in such manner that a roller is raised from the table and another roller is placed upon the table. The linear movement of the carriage begins only when a roller is adequately pressed against the table. One of the rollers has. an adjustable brake disc to make certain that the operations swinging-moving take place one after the other one to regulate the extent of pressure of the roller against the table. Pressure rollers are mounted in front of the folding rollers to make certain that the paper being folded will retain its location when the intermediate fold is being formed. Preferably when paper is inserted one of the pressure rollers can be moved into a raised position to provide free movement for one end of the paper. Since German Industry Norm DIN824 requires a triangular fold in the folding of a sheet, the table has at its rear end a table plate section which is movable separately up and down. This section clamps during its downward movement a triangular end section of the incoming end of a sheet and moves it up wardly to a small extent by means of a pressure ledge clamping the sheet end up to the table top surface, so that a sharp-edged fold is produced at this section when the next fold is being formed. In order to produce the required transverse folds in a sheet which has been subjected to intermediate folding, the sheet passes the folding wheels located upon one of the shafts at the outlet side of the table. These folding wheels can be shifted upon the shaft, so that transverse folds can be made with any desired spacing. Suction openings provided in the table are used for holding the incoming sheet end. Suction air is turned off when the paper with intermediate folding is transmitted to the rotating folding rollers. Since the carriage consists of two slide rings joined by a transverse axle which are guided in rails, a good linear shifting can be attained. Furthermore, the construction is a most advantageous one.
The invention will appear more clearly from the following detailed description when taken in connection with the accompanying drawings showing by way of example only, a preferred embodiment of the inventive idea.
In the drawings:
FIG. 1 is a top view of a folded sheet of paper with transverse folds and having the size of the German Industry Norm A.O.
FIG. 1a is a side view of the sheet of paper shown in FIG. 1.
FIG. 2 is a top view of the folding machine of the present invention.
FIG. 3 is a side view of the machine shown in FIG. 2.
FIG. 4 is a section through the folding rollers at the time a paper sheet is inserted, a pressure roller being shown in its raised position.
FIG. 5 is a side view illustrating the wheels driving the folding rollers.
FIG. 6 is a top view of the machine parts shown in FIG. 5.
FIG. 7 is a diagrammatic side view illustrating the entry of a sheet end when the pressure roller is raised.
FIG. 8 is similar to FIG. 7 and shows the operation of the pressure roller. v
FIG. 9 is similar to FIGS. 7 and 8 and shows the formation of the first intermediate fold while the carriage is moving.
FIG. 10 is a similar diagram illustrating the formation of a second intermediate fold.
FIG. 11 is a section along the line AB of FIG. 2 and illustrates the table plate forming the triangular sectrons.
FIG. 12 is similar to FIG. 11 and shows the table plate as clamping the end of a paper sheet.
FIG. 13 is similar to FIGS. 11 and 12 and shows the table plate as having been moved slightly upwards to provide a straightening of the sheet end.
FIG. 14 is a diagram illustrating roller action upon the straightened portion to provide a sharp fold edge; and
FIG. 15 is a diagram showing the linearly moved table when a sheet is transmitted to the folding rollers.
The folding machine shown in the drawings has a fixed table 1 and an upper table 2 movable in the direction of the arrowx shown in FIG. 3. Pairs of rails 3 and 4 are located above the table. Slide rings 6 forming the carriage 5 are guided in the rails 3 and 4.
The transverse axle 7 which interconnects the slide rings 6 carries a swinging member 8 provided with axles 11 and 12 which carry folding rollers 9 and 10 driven in opposite directions.
To provide a rotation of the folding rollers 9 and 10 in the opposite direction, gear wheels 13 and 14 are located on one side of the rollers upon axles 11 and 12 with fixed torsion. The diameter of the folding rollers corresponds precisely to the pitch diameter of the gear wheels 13 and 14. The transverse axle 7 of the carriage 5 passes through the point of intersection of the line touching the pitch circles of the gear wheels 13 and 14 with the central connecting line.
Due to this arrangement the swing 8 can be moved linearly and its swinging movement about the transverse axle 7 is provided. The center of the transverse axle 7 and the corresponding slide rings 6 are located so high above the table 1 that the swing 8 with its rollers 9 and 10 can move due to the pushing and pulling action of the crank drive 15 or of the connecting rods 16 engaging the extending arms of the swing 8, the movement of the swing taking place linearly when the pushing is to the left (FIG. 3). During this movement the folding roller 10 is pressed firmly against the table. When the left dead point of the crank drive 15 is reached, the swing 8 initially stands still and then carries out such a swinging movement that the folding roller 10 is raised from the table and the folding roller 9 is pressed against the table. The linear return movement takes place only when the roller 9 is pressed with sufficient strength against the table.
An adjustable brake disc 18 is mounted upon the axle 11 to make certain that the operations swingingshifting take place one after the other and to regulate the pressure of the rollers 9 and 10 against the table. The braking force of the disc 18 acts against the pushing and pulling force of the crank drive 15 so that there is a lesser resistance during the swinging movement. Thus a swinging movement takes place each time that the direction of the linear movement of the swing is changed.
Bearing bolts 19 and 20 are fixed upon the swing 8 on both sides thereof at the intersection of the central connecting line of the gear wheels 13 and 14 with the pitch circle line of the gear wheel 14. Links 21 and 22 are mounted upon the bolts 19 and 20. A shaft 23 carried by the slide rings 24 connects the ends of the links 21 and 22 and is located opposite the bearing location.
A gear wheel 25 is fixed upon the axle l2 and is of the same size as the gear wheels 13 and 14. The gear wheel 25 meshes with an intermediate gear wheel 26 carried by the link 22. A gear wheel 27 consists of two parts 27' and 27". The part 27" meshes with the gear wheel 26 and is mounted by a free run coupling upon the shaft 23. The gear wheel part 27 meshes with a bottom rack 28. The rack 28 is movable longitudinally and meshes with a pinion 29 of a driving motor 30.
Upon the other end of the shaft 23 there is also a rotatably mounted gear wheel 31 which meshes with a top rack 32. Gear wheels 27 are of the same size as the gear wheels l3, 14, 25 and 26.
Due to this arrangement of the driving wheels and the racks the folding rollers 9 and 10 do not change their direction of rotation during the forward and return movements of the carriage 5. During the forward movement of the carriage 5 the gear wheel 27 engages and rotates upon the rack 28 and drives the folding roller 10 through the intermediate gear wheel 26 and the gear wheel 25. The gear wheel 14 of the folding roller 10 meshes with the gear wheel 13 of the folding roller 9 and thus rotates the latter. During this movement the gear wheel 27 upon the shaft 23 runs empty.
During the return movement of the carriage the rotatably mounted gear wheel 27' turns upon the rack 28 but the shaft 23 and the gear wheel 27" do not partermediate wheel 26 and the gear wheels 25, 14 and 13 ticipate in this movement. The gear wheel 31 rotates upon the rack 32 and drives the folding rollers 9 and 10 through the shaft 23, the gear wheel 27", the intermediate wheel 26, the gear wheel 25 and the gear wheels 14 and 13, whereby the folding rollers retain their direction of rotation.
The circumferential rotation imparted to the folding rollers 9 and 10 is exactly equal to the speed with which they turn upon the table.
Pressure rollers 34 and 35 are carried by swinging arms 33 and are located in front of the folding rollers 9 and 10. The pressure roller 34 can be moved to a raised position by a magnet 36 fixed to the swing 8.
The table 1 is provided upon the rear end with a plate section 37 movable up and down. A pressure link 39 which is actuated by a magnet 38 cooperates with the plate section 37.
To provide transverse folds in a sheet being folded, shafts 41 provided with folding wheels 40 are located adjacent the table 1. One wheel 40 has a triangular rib 40' and the wheel belonging thereto has a corresponding triangular groove 40 (FIG. 2).
The operation of the described machine is as follows:
Let it be assumed that a paper sheet is to be folded the size of which is that of the German Industry Norm DINAO (FIG. 1 The sheet is placed upon the supporting table surface 42 (FIG. 3) so that its narrow side extends parallel to the axles of the folding rollers. The sheet is shifted in the direction perpendicular to the axles 11 and 12 and passes the light gates 43 which establish a' specific folding program for sheets of specific size. Then the paper sheet is guided by the conducting sheets 44 and 45 until the narrow edge of the paper sheet reaches the point of contact of the folding rollers 9 and 10. Further shifting will bend the paper so that it will press against the key 46 of the microswitch 46 and thereby start the machine (FIG. 4). This arrangement makes certain that the mechanisms will start their motors only when the paper edge is definately located at the line joining the folding rollers and when the paper is subjected to a certain pushing pressure, so that when the folding rollers begin to rotate they will immediately move the paper sheet. The microswitch 46 will switch on the magnet 26 so that the pressure roller 34 is moved into its raised position. Furthermore, the microswitch 46 switches on the irreversible motor 30,
the pinion 29 of which meshes with the rack 28 and shifts it in the direction of the arrow y (FIG. 6). The
rent emerging from the nozzles 47 (FIG. 4) and will be' guided at the same time toward the surface of the table. The folding rollers 9 and 10 which at that time do not move longitudinally, transport by their rotation the paper sheet B further across the table until the front edge of the sheet reaches the light gates 48 (FIG. 7). This will stop the motor 30 which drives the folding rollers 9 and 10 through the rack 28.
If thicker paper sheets are used, the safe guiding of the sheets may be assured by providing a guiding strip 49 shown by broken lines in FIG. 4, which swings back after the end of the sheet has reached the table surface. I
The pressure roller 34 also facilitates the proper position of the paper sheet. Then the crank drive starts and causes a forward movement of the carriage 5 in the course of which the paper sheet B forms a loop which is frictionally pressed by the folding roller 10, as shown in FIGS. 8 and 9. After reaching the end position, which is the dead point position of the cranks 15, the swing 8 is swung about the transverse axle 7 during further crank movement, whereby the folding roller 9 moves into engagement with the table surface, while the other roller 10 is raised from this surface, as shown in FIG. 10.
Then the procedure of loop forming and sharply shaping the fold is repeated in the same manner as already described. The pressure rollers keep during this folding procedure the sheet firmly upon the table and prevent it from shifting.
It is possible to provide any other smaller paper fold, in which case the cranks will carry out only a part of a complete rotation and will change their direction of rotation.
The triangle, which is required by the German Industry Norm DIN824 is folded according to the same procedure. When the first paper sheet is moved in, the angle-shaping plate 37 is located in its upper position (FIG. 11). After the first paper sheet is placed, the plate 37 moves downwardly and bends a triangular portion B with light roundings (FIG. 12). Then the pressure ledge 39 which is horizontally movable under the plate 37 and which is provided with a rubber strip 50, will be actuated by the magnet 38 and will press the bent triangular end portion B of the sheet against a smooth front wall 1 of the table 1. Then the plate 37 is moved upward up to the table surface. This movement will raise the paper so that it will form a bend B" above the table surface (FIG. 13).
When the next paper sheet arrives this bend will be shifted by the folding rollers from right to left and it changes into a sharp fold bent against itself, as shown in FIG. 14. After the sheet B has been provided with an intermediate fold and with a bent triangle, the machine parts which carried out these operations will move back to their initial positions. The upper table 2 is shifted in the direction of the arrow x (F. 15) toward the rotary folding rollers 40 and takes along with it the longitudionally folded paper sheet B, which is held upon the table by suction openings 51. Then the paper sheet is engaged by the rollers 40. During this operation the plate 37 is moved downwardly to such an extent that it provides free movement for the upper table 2 and the triangular sheet portion B. Due to the sharp folding edge of the sheet portion B and with the assistance of plates 52 the triangular sheet portion B will be bent over the sheet B. Suction air is switched off; when the paper sheet is taken over by the rollers 40 it will be pressed by the rollers and due to the projections and grooves provided upon the rollers (FIG. 2), it will receive two transverse folds B' located on opposite sides (FIG. la), so that the separate sections can be conveniently bent by hand.
1. Machine for the zigzag folding of paper sheets and the like, comprising a table adapted to carry a paper sheet, a carriage, a crank drive connected with said carriage for moving said carriage forwards and backwards above said table, a swing mounted in said carriage and connected with said crank drive, two folding rollers carried by said swing, two pressure rollers, arms connecting said pressure rollers with said folding rollers, means moving at least one of said pressure rollers into a raised position, two racks located on opposite sides of said carriage, and means connected with said racks and said folding rollers and actuating said folding rollers to press one of said folding rollers against a paper sheet upon said table during the forward movement of said carriage and to press the other one of said folding rollers against the paper sheet upon said table during the backward movement of said carriage.
2. Machine in accordance with claim 1, comprising braking means connected with at least one folding roller and acting upon said crank drive.
3. Machine in accordance with claim 1, comprising a plate located close to an end of said table and movable relatively to said end to bend angularly a paper sheet portion extending beyond said end.
4. Machine in accordance with claim 3, comprising a pressure ledge located adjacent said plate and means moving said ledge into engagement with said bent paper sheet portion to raise it above the table.