GB2033304A

GB2033304A - A multiple-head printer

Info

Publication number: GB2033304A
Application number: GB7936215A
Authority: GB
Original assignee: AFFRANCHIS SEMENT ET LE TIMBRA
Current assignee: AFFRANCHIS SEMENT ET LE TIMBRA
Priority date: 1978-10-26
Filing date: 1979-10-18
Publication date: 1980-05-21
Also published as: DE2942578A1; GB2033304B; FR2439675A1

Abstract

The printer has a plurality of heads (1, 2, 3) to print with print wheels information on a document (4) during a single pass of the document through the printer. The various heads are arranged to print both on the front and on the back of the document. To avoid mutual interference between front and back printing the heads are arranged to print at different levels on different sides. Where there is a plurality of heads on the same side, they can be at the same level as each other. A motor 11 steps all the heads simultaneously across the document, along guide rails 7-10. <IMAGE>

Description

SPECIFICATION A multiple-head printer The present invention relates to a multiplerhead printer which is capable of simultaneously printing a plurality of texts (whether identical or not) on one or more stationary documents.

Bank cheques, and also some other forms of document, undergo several printing operations before being discarded. The initial printing operation is conventional bulk printing of blank cheque forms at a printer's and is not the concern of the present invention. Subsequent printing operations are individual to each cheque (or other form) and it is to such individual operations that the printer of the present invention is applicable.

A first "individual" operation is the personalisation of cheques with numbers that enable cheque and counterfoil to be matched In some systems these individual numbers are printed onthe back of the cheque and counterfoil while other information, e.g. account number and customer's name are printed on the front.

A second "individual" operation is performed by some categories of corporate customers who make out large quantities of cheques by machine.

Each cheque has an individual addressee and a specific sum to be paid, and again some systems require information to be printed on both sides of the cheque, and/or its counterfoil(s).

At least one more "individual" operation occurs when the banks process a cheque to transfer funds. Again there are requirements for information to be printed on both sides of the cheque.

Up to now such "both sides" requirements have been met by passing the same cheque through two different machines, or twice through the same machine. Either solution leads to extra manipulation, and hence loss of operator time, and lends itself to errors of the kind where the front and back printing (known as "recto" and "verso" to printers) on one cheque does not correspond.

The present invention provides a printer capable of printing on both sides of a document in a single pass.

Specifically the present invention provides a multiple-head printer for printing at least one document, each of the heads being installed in a corresponding carriage and including a printing wheel with characters engraved on its periphery, said printing wheel being rotated by a motor which is servo-controlled by a coder, said motor and said coder being disposed on said carriage which, guided by rails, is moved longitudinally in a direction parallel to the documents by a main motor outside the carriage and said printing wheel being caused to print on the document by an electromagnet, said rotation, movement and printing operations combined together being programmed in a memory, the heads being disposed on either side of the document, recto and verso, the verso heads being disposed at different heights with respect to the recto heads, the heads of the same recto group or verso group being disposed at the same height.

An embodiment of the present invention is described by way of example, with reference to the accompanying drawings in which the same components shown in several figures bear the same reference symbols and in which: Figure 1 is a schematic plan view of a threeheaded printer; Figures 2 and 3 are respectively, a side and an end view of the same printer; and Figure 4 is an enlarged side view of a head.

Figures 1 to 3 show the general disposition of a multiple-head printer, the heads comprising three printing heads 1, 2 and 3. The heads 2 and 3, here called the recto heads, are disposed one side of a document (or documents) such as 4 on which information is printed, and the head 1, here called the verso head, is disposed on the other side.

Between the head 1 and the group of heads 2 and 3, there is a guide passage for documents 4 which are conveyed by a conveyor belt 5 until they are positioned by means of the move feelers and the stop feelers 6.

The heads 2 and 3 are disposed at the same height above the ground while the head 1 is disposed at a different height. The heads 1, 2 and 3 are arranged in carriages which slide on guide rails such as 7, 8, 9 and 10, the rails 9 and 10 supporting the two carriages of the heads 2 and 3 and the rails 7 and 8 guiding the carriage of the head 1. A motor 11 simultaneously drives and controls the three carriages of the three heads 1, 2 and 3 step by step. It is servo-controlled by a coder which receives instructions from a memory which is not shown. The shaft of the motor 11 drives two studded belts 12 and 13. The belt 12 includes a catch pin or stud 14 for moving the carriage of the head 1 and the belt 13 includes two catch pins 1 5 and 1 6 for the two carriages of the heads 2 and 3.It follows that if the recto heads 2 and 3 print from left to right, the verso head 1 prints from right to left. In operation, therefore, all three carriages move in the same direction.

Figure 4 shows in detail a printing head 2. It is constituted mainly by a printing wheel 1 7 whose upper peripheral portion 18 is engraved with the print characters. The character to be printed is chosen by rotating the printing wheel, whose lower portion includes a toothed wheel 19 driven by a toothed wheel 20 fixed to the shaft of a stepping motor 21 which is servo-controlled by a coder 22 constituted by a disk which co-operates with sensors. The coder 22 is controlled by the instructions from a memory, not shown, the instructions being generated on a keyboard of known type.

The printing wheel 1 7 includes a rotating axle 23 supported by a hinged lever 24 whose pivot 25 is disposed level with the edge of the printing wheel adjacent to the document 4, Hence, movement of the character-bearing portion of the wheel 1 7 when it prints is reduced to a minimum.

Such movement is obtained by the action of an electromagnet 26 and by a spring 27, the electromagnet being controlled by the memory, not shown. Movement of the printing wheel 17 causes the toothed wheel 19 to move with toothed wheel 20, which is stationary. The printing wheel 17 also includes an intermediate toothed disk 28 provided with slots. There are as many slots as there are characters. A fixed stud 29 integral with the carriage realigns the printing wheel when it prints by engaging the stud 29 in the corresponding slot of the toothed disk 28. Two anvil plates 30 fixed to the frame of the printer are disposed each facing the characters of the printing wheels 1 7 on either side of the document 4. Each of the anvil plates 30 is elongate. Their lengths are at least equal to the distance between the move feelers and the stop feelers 6.The anvil plates 30 absorb the shock of the printing wheel through the document and a transfer tape 31 which is guided, at the level of the printing wheel 17, by a plurality of rollers only two of which 32, 33 are shown. A motor 34 fast with the frame and independent from the carriage keeps the tape taut and winds it onto a take-up reel 35. A second mqtor, not shown, can also be installed to unwind a feed reel.

The tape 31 remains motionless while the printer is printing. The return of the carriage moves the tape forward.

The printer operates as follows: The document 4 conveyed by the conveyor belt 5 is stopped. The three heads 1, 2 and 3 receive the data which is peculiar to them so that they can choose the character which is to print. The three printing wheels 1 7 print, controlled by their respective electromagnets 26 and the three heads 1, 2 and 3 taken as a whole move forward by one step. Another configuration of the three printing wheels 1 7 is formed, there is another impression, the printing wheels move forward again and so on.

It should be observed that the three heads move together (they are actuated by the same motor 11), but that they are independent from one another as far as concerns the choice of characters (three motors 21) and as far as concerns the choice whether or not to print (three electromagnets 26).

Applications come within the field of automatic processing of documents where the convoying, recto and verso printing and receipt of documents are automatic.

Claims

1. A multiple head printer for printing at least one document, each of the heads being installed in a corresponding carriage and including a printing wheel with characters engraved on its periphery, said printing wheel being rotated by a motor which is servo-controlled by a coder, said motor and said coder being disposed on said carriage which, guided by rails, is moved longitudinally in a direction parallel to the document by a main motor outside the carriage and said printing wheel being caused to print on the document by an electromagnet, said rotation, movement and printing operations combined together being programmed in a memory, the heads being disposed on either side of the document, recto and verso, the verso heads being disposed at different heights with respect to the recto heads, the heads of the same recto group or verso group being disposed at the same height.

2. A printer according to claim 1, wherein said main motor drives all of said recto and verso carriages in the same direction by means of belts which each include at least one catch pin which co-operates with each of said carriages.

3. A printer according to claim 1, wherein two stationary elongate anvil plates are each disposed facing the printing wheels of the recto heads and of the verso heads on either side of the document.

4. A printer according to claim 3, wherein said printing wheel includes an axle whose base is integral with a lever which pivots about a pivot disposed vertically to the end of the printing wheel facing said anvil plate.

5. A printer according to claim 4, wherein said printing wheel is integral with a disk which includes a plurality of slots, there being as many slots as there are characters on the printing wheel, each said slot co-operating with a stationary catch pin which is integral with the carriage with a view to centring the character of the printing wheel when it prints by engaging said catch pin in said slot.

6. A multiple-head printer substantially as herein described with reference to and as illustrated in the accompanying drawings.