Printer having a sheet cutter

Abstract: A printer having a cutter 6 comprising: storage means 2 for storing printer control programs such as a data edition program, a printing control program and a cutter control program, said means having a random access memory for storing the predetermined length of each of sheet divisions arranged on the web to be cut out, a whole length of a printing zone in each of the sheet divisions and a blank distance between adjacent two printing zones of the sheet divisions or the like; and a central processing unit 1 for executing cutting operation of the cutter 6 for the sheet division according to the data and the programs read out from said storage means, to cut out a sheet in the predetermined length with a printed zone therein said central processing unit 1 establishing by precalculation a continued travel length L of the web from a travel reference position where any predtermined point in the sheet or a subsequent sheet division is placed in a predetermined relative position to the printer after printing of said printed zone to a travel end position where a cross line of the web to be a rear edge of the sheet is aligned with a cutting line of the cutter 6.

Description: DETAILED DESCRIPTION OF THE INVENTION FIELD OF APPLICATION The present invention relates to a printer such as a label printer having a cutter, which can cut a sheet or web at a desired position. Prior Art Conventionally, the following systems have been used for cutting a continuous sheet or web (such as recording sheet) in a printer. (a) a system in which the cutting device can be moved along the direction of advance of the sheet and is set to the cutting position on the sheet (movable type cutting device), (b) a system in which a mark is provided at the position to be cut on the sheet and the mark is detected and the sheet is cut at the mark (fixed cutter type cutting device), (c) a system in which the sheet is cut to a length defined by the length of a form according to a mechanical structure (fixed cutter type cutting device). Therefore, such a conventional cut control system can cut the sheet only at a predetermined position on the continuous sheet or web and it is difficult to cut the sheet at a desired position each time. Particularly, in the case where the fixed cutter type printer in the above systems (b) and (c) is used as a label printer, the printer performs a series of steps including printing the necessary content on each of a plurality of zones (each corresponding to a finished label address form or label such as a postal address form or label form having predetermined form and size) of the sheet material, then cutting the sheet into divisions each constituting a respective one of the labels and adhering the cut divisions automatically onto goods. However, the series of steps of printing-cutting-adhesion is required to be handled rapidly and in large amount. However, conventionally in the printer performing the printing-cutting operation, when the printing for each zone is completed, it is a common practice that the sheet is simply sent forward to the cutter position and cut and then sent back to the printing position and thus considerable time is inevitably wasted. EP-A-0 312 201 discloses a printer including a cutter for cutting a sheet into predetermined lengths, each having a printed zone thereon, and means for controlling feeding of the sheet. EP-A-0 314 517 discloses apparatus including a paper feeding control device and a cutter for cutting a sheet into predetermined lengths each having a printed zone thereon and including a central processing unit for executing cutting operation of the cutter according to data and programs read out from a storage means. An object of the present invention is to provide a printer including a cut control system which can cut the web to a desired size. Another object of the present invention is to provide a printer having a cutter which can efficiently perform the operations of printing and cutting, and more particularly shifting the web between the operating positions for printing and cutting. SUMMARY OF THE INVENTION According to the present invention there is provided a printer including a stepping motor for feeding or advancing a web, a printing head for printing on a surface provided by the web, and a cutter at a distance downstream of the printer head, the cutter being adapted to cut sheets of a predetermined length from the web when the feeding of the web and operation of the printing head are stopped, the sheets corresponding to portions, hereinafter referred to as "sheet divisions", of the web, the printer comprising: storage means for storing one or more printer control programs, said means having a random access memory for storing data comprising a predetermined length of each sheet to be cut from the web, a length of a printing zone in each sheet division and the length of a blank region between the respective printing zones of adjacent sheet divisions; and a central processing unit for controlling operation of the cutter according to the stored data and one or more programs and in accordance with a distance L from a reference position where a predetermined point of one of the sheet divisions is in a predetermined position relative to the printer after printing of each printing zone to a travel end position in which a transverse line of the web to be a rear edge of the sheet division is aligned with a cutting line of the cutter; characterised in that the printer control program or a first of the printer control programs effects operation of the printer such that after completion of printing on the printing zone of each sheet division, except the last in respect of which the printer prints on the printing zone, and when the web has been advanced by a distance equal to the length of said blank region from the printer printing on the printing zone of the subsequent sheet division is begun, when the web has travelled by the distance L from the reference position the printing on said subsequent sheet division by the printing head is interrupted, the cutter is operated, and the feeding of the web is restarted so that the printing head continues printing said subsequent sheet division. In a preferred embodiment of the invention, the storage means stores more than one of said printer control programs; and a second of the printer control programs effects operation of the printer such that after completion of the printing on the printing zone of one sheet division, except the last in respect of which the printer prints on the printing zone, feeding of the web is continued until the web has travelled by the distance L from the reference position, the cutter is then operated, the web is then retracted by the distance L and the feeding of the web is restarted and the printing head starts printing the subsequent sheet division; a third of the printer control programs effects operation of the printer such that after completion of the printing on the printing zone of each sheet division, except the last in respect of which the printer prints on the printing zone, the web is advanced until the web has travelled by the distance L from the reference position, the cutter is operated and the feeding of the web is restarted and the printing head starts printing the subsequent sheet division; and level switching means for selecting any one of the first, second and third programs for effecting operation of the printer. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a block diagram showing a printer according to the present invention; Fig. 2 is a schematic drawing of the printer; Fig. 3, which consists of Figs. 3A and 3B, is a flow diagram showing programs in accordance with which the printer may operate; Figs. 4, 5 and 6 are drawings illustrating the steps of web feeding for printing and cutting in operation of the printer; and Fig. 7 is a flow diagram showing modifications of part of the program of Fig. 3. DESCRIPTION OF PREFERRED EMBODIMENT Fig. 1 is a block diagram of a printer according to the invention and Fig. 2 is a schematic drawing of the printer. Referring to Fig. 1, the printer comprises a system bus B, a CPU 1, a control program storage means 2, a printing control means 3, a thermal head 4 for printing, a stepping motor 5 for advancing (feeding) and withdrawing a recording web or sheet S (see Fig. 2), a cutter 6 for cutting the sheet at a defined position, a communication interface 7 for transferring information from external sources to the CPU, and input means 23 for an operator. The input means 23 may be a keyboard including a level switch 23 a for switching cutting operation levels. The control program storage means 2 comprises a rewritable random access memory (RAM) and stores control programs for the printer. Such programs may be a data edition program, a printing control program and also a program for controlling operation of the cutter 6 in relation to printing operation, sheet sending operation (i.e. sheet advance and withdrawal) and other operations. The thermal head 4, the stepping motor 5 and the cutter 6 are controlled by the CPU 1 in accordance with the programs stored by the storage means 2. The level switch 23 a comprises a part of the keyboard or a manual switch. Any one of a number of selection signals may be selectively generated by the switch 23 a or can be input from a host computer through the communication interface 7 with no use of the level switch 23 a . A corresponding control program relating to operation of the cutter 6 and feeding and withdrawal of the web is supplied from the storage means 2 to the printing control means 3 in accordance with the signal generated by the switch 23 a . The respective operations effected by the control programs are shown in Fig. 3 and are described below. Referring to Fig. 2, the web S is printed on and cut into sheets by the printer. The web S may comprise a paper sheet, a plastic film and a tacky (adhesive) paper. The printer comprises a web feeding roller 8, an impression roller 9, a platen roll 10 for feeding the web S from the rollers 8 and 9 to the printing head 4, a web driving belt 11, a platen driving belt 12 and belt pulleys 13, 14 15 and 16. The cutter 6 is placed downstream of the printing head and may comprise a fixed blade 17, an up-and-down movable blade 18, an eccentric cam 19 for moving the movable blade 18 up and down and a cutter motor 20. Alternatively the movable blade 18 can be of rotary type (rotary blade) in place of up-and-down moving type. Now, the operation of the present invention will be described with reference to Figs. 3 to 6. As described below the web S is cut transversely into sheets of predetermined length each corresponding to a longitudinally extending portion or "sheet division" of the web. Where each of the sheet divisions is to be tacky paper the tacky papers are constituted by laminating surface substrate sheets 21 coated with an adhesive onto a release paper web 22 as shown in Fig. 4. The width (i.e. the dimension transverse to the feeding direction) and the length (i.e. the dimension extending in the feeding direction) of each surface substrate sheet 21 and the distance between the adjacent surface substrate sheets depend on the type of the tacky papers and the intended use the tacky paper. Information or data including the intended length of one sheet of the tacky paper, the distance between surface substrate sheets, the web movement, referred to as "web travel length", L from a position (referred to below as the "standard position") in which a predetermined point of one of the sheet divisions is in a predetermined position relative to the printer to a travel end position in which a transverse line of the web to be a rear edge of the sheet division is aligned with a cutting line of the cutter and the length of the printing zone of the tacky paper are input to the RAM of the program storage means 2. The length of the sheet divisions cut from the web can be varied as required by changing the web travel length L stored in the RAM for each predetermined number of sheet divisions to have a particular length. A program of an operation as a printer (Fig. 3) is started. Any one of three levels (I, II and III) of operation may be selectively executed. The printing operation and the web operation for each level are controlled by the CPU 1 and the printing control means 3. Each level of operation is described below. In each operation level unless otherwise stated the web is advanced and the CPU 1 confirms when the rear edge or other reference point of each sheet division reaches a predetermined reference position ℓ₁, which is separated from a travel end position ℓ o in alignment with the blade of the cutter 6 by the web travel length L. Fig. 4 illustrates Operation Level I. When the first sheet division has been printed completely, the web S is advanced to a position where printing of the second sheet division is started. The printing of the second sheet division proceeds and when the rear edge of the first sheet division has advanced by the web travel length L from the reference position ℓ₁ to reach to the position ℓ o in alignment with the blade of the cutter 6, printing is temporarily stopped. The first sheet is then cut from the web and the printing of the second sheet division is completed as the web advances. Thereafter, the cutting of second sheet division and the printing and cutting of the third and subsequent sheet divisions are effected in the same manner. In general the relationship between the operations applied to the (n + 1) and (n + 2)-th sheet divisions is the same as that between the n-th and (n + 1)-th sheet divisions. Fig. 5 illustrates of Operation Level II. After the first sheet division has been printed completely and the rear edge of the first sheet division has advanced by the length L from the reference position ℓ₁ to the position ℓ o , in alignment with the blade of the cutter 6, the cutter is operated to cut the sheet division from the web. The web S is then pulled back or retracted by a distance equal to the length L. Then, printing of the second sheet division is started. Thereafter, subsequent sheet divisions are printed and cut in the same manner. I.e. the (n + 1)th sheet division is printed and cut in the same manner as the nth sheet division. Fig. 6 illustrates Operation Level III. After the first sheet division has been printed completely, the web is advanced by the web travel length L so that the rear edge reaches the position ℓ o and the cutter 6 is operated at this position to cut the sheet division from the web. Immediately after the sheet has been cut from the web, the web is advanced for printing of the second sheet division. Thereafter, subsequent sheet divisions are printed and cut in the same manner. I.e. the (n + 1)th sheet division is printed and cut in the same manner as the nth sheet division. Operation of the printer can be selected from the three levels mentioned above according to requirements. It is also possible that the level switch 23 a is not provided in the printer but it is constituted to execute only one operation level as a monofunctional device. The reference point on the web for determining the start point of the travel distance can be set optionally, for example, at the rear edge of the surface substrate sheet 21. However, the position of the web to be cut can be also determined at the rear end of the printed zone or by the generation of the printing signal itself. The features and the effects of each level are as follows. When Level I is selected, web feeding for the printing can be utilized in common with the feeding for cutting and sending back of the sheet is unnecessary after the cutting. Hence, the period or time consumption required for the total operation for printing and cutting can be marked decreased. Operation Level II sends the web forward and backward by the length L. However, it causes no deterioration of printed quality caused by interrupting printing of subsequent sheet division in Level I. Also in Level II, the length of L can be set at L = 0 and L < 0 in addition to a predetermined positive value according to the relationship to the length of the printing zone in the sheet division. Fig. 7 shows part of the flow diagram of Fig. 3 (specifically part of Fig. 3B) modified to provide three branches corresponding to the cases where L < O, L = O and L > O in Level III. According to the procedure section, printing and cutting can be executed efficiently. In the case L > 0, the web is cut when the reference point of the web has advanced by the distance L from the reference position. When L = 0 after the reference point of the web has reached the reference position, the web is pulled back by a distance | L | and stopped and cut and then pushed forward by | L |, back to the position in which the reference point is in alignment with the reference position. Operation Level III is same as Level I in that the web does not return by the distance L after the web has been cut and the print quality is good but care should be taken in that the length of blank portions between the printed zones is not increased in the sheet division other than the printed zone.

Claims: A printer including a stepping motor (5) for feeding or advancing a web (S), a printing head (4) for printing on a surface provided by the web, and a cutter (6) at a distance downstream of the printer head, the cutter being adapted to cut sheets of a predetermined length from the web when the feeding of the web and operation of the printing head are stopped, the sheets corresponding to portions (S n ), hereinafter referred to as "sheet divisions", of the web, the printer comprising: storage means (2) for storing one or more printer control programs, said means having a random access memory for storing data comprising a predetermined length of each sheet to be cut from the web, a length of a printing zone in each sheet division and the length of a blank region between the respective printing zones of adjacent sheet divisions; and a central processing unit (CPU) for controlling operation of the cutter according to the stored data and one or more programs and in accordance with a distance L from a reference position where a predetermined point of one of the sheet divisions is in a predetermined position relative to the printer after printing of each printing zone to a travel end position in which a transverse line of the web to be a rear edge of the sheet division is aligned with a cutting line of the cutter; characterised in that the printer control program or a first of the printer control programs effects operation of the printer such that after completion of printing on the printing zone of each sheet division, except the last in respect of which the printer prints on the printing zone, and when the web has been advanced by a distance equal to the length of said blank region from the printer printing on the printing zone of the subsequent sheet division is begun, when the web has travelled by the distance L from the reference position the printing on said subsequent sheet division by the printing head is interrupted, the cutter is operated, and the feeding of the web is restarted so that the printing head continues printing said subsequent sheet division. A printer according to Claim 1, wherein: the storage means stores more than one of said printer control programs; and a second of the printer control programs effects operation of the printer such that after completion of the printing on the printing zone of one sheet division, except the last in respect of which the printer prints on the printing zone, feeding of the web is continued until the web has travelled by the distance L from the reference position, the cutter is then operated, the web is then retracted by the distance L and the feeding of the web is restarted and the printing head starts printing the subsequent sheet division; a third of the printer control programs effects operation of the printer such that after completion of the printing on the printing zone of each sheet division, except the last in respect of which the printer prints on the printing zone, the web is advanced until the web has travelled to the distance L from the reference position, the cutter is operated and the feeding of the web is restarted and the printing head starts printing the subsequent sheet division; and level switching means (23a) for selecting any one of the first, second and third programs for effecting operation of the printer. A printer according to claim 2, wherein the level switching means is manually operable to select any one of the first, second and third programs. A printer according to any preceding claim, wherein the printer control programs comprise one or more of a data edition program, a printing control program and a cutter control program.

Inventors: FUJII KENICHI, HONGO TAKAYASU, MATSUBARA MOTOKI, SASABE SETSUO, FUJII, KENICHI, HONGO, TAKAYASU, MATSUBARA, MOTOKI, SASABE, SETSUO
Applicants: NEW OJI PAPER CO LTD, NEW OJI PAPER CO., LTD.
Application year: 1991
Main classification: B41F13
IPC codes: B65H35, B41J11, B65H43