US1839601A - Duplicating printing machine - Google Patents

Description

Jan. 5, 1932.

P. R. SEWARD 1,839,601

DUPLICATING PRINTING MACHINE 2 Sheets-Sheet 1 Filed Oct. 10, 1950 2 Sheets-Sheet 2 Filed Oct. 10 1950 JEN/@1200 fiejuy Jena? 7/;

Patented Jan. 5, i932 carries PERCY R. SEWARD, OF MINNEAPOLIS, IIIIG'IIESOTA DUPLICATING PRINTING- IVIACHINE Application filed October 10,1930. Serial No. 437,708.

This invention relates to duplicating print ing machines and provides improved ribbonfeeding means whereby the ribbons are caused to wear longer and more evenly and uniform reprinting is produced. I

Generally stated, theinvention consists of the novel devices, combinations of devices and arrangement of parts hereinafter described and defined in the claims.

Particularly, the invention relates to duplicating machines of the type wherein the type on the segment of a rotary drum or member are brought into contact with the paper and the latter pressed against the ribbon during a portion of the rotation of the drum or type carrier; and the ribbon is given a step by step feed movement during the travel or that part of the rotation of the type carrier that is between the printing actions. In duplicating .machines of the above character, means has hitherto been provided for givingone short feed movement LO, the ribbon during each printing actionand, in fact, the nature of r such dmalicatinginachines has been such that it has not been considered practically possible to impart either very long length movements or a plurality of short movements to the rib bon during successive printing operations. The result of this old short feed movement has been that with a. type cylinder say of six inches circumferential extent, extending through approximately 180 degrees," about eighteen successive movements, one between.

each printing operation has been required to present entirely new or different ribbon surface to the type of the cylinder and from this it has further resulted that any particular letter would not be uniform. My invention provides means for imparting a'plurality of movements to the ribbon between each printing operation so that new or other parts of the ribbon would be presented to the type of the cylinder during live or six succcssive printing operations.

The invention, in its commercial form, hasbeen designed and particularly adapted for application to a duplicatin machine nane ufactured by the American Multigraph Company of Cleveland, Ohio, and by them views.

designated as their No. 36, Gammeter printei. I I V In the accompanying drawings, which illustrate the invention, like characters indicate like parts throughout the several Referring to the drawings: Fig. l is a front to rearvert1cal section taken about centrally through a duplicating machine'ofthe character just above indicated and illustrating the present invention applied thereto; Y I

Fig. 2 is a fragmentary vertical section taken on the line 22 of Fig; 2;

Fig. 3 is a front to rear vertical section takon on the line 34 of Fig. 2, looking toward the left; i

Fig. 4 is a front to rear vertical section takeiion the line-34 of Fig. 2, looking toward the right; and

Fig. a fragmentary the line 55 of Fig. 1.

The framework of the machine is made up section taken on chiefly of a cast base 6, head plate 7 and a top tie-bar 8, which parts are rigidly connected. Journaledin axial hubs of the head plates 7 and extended through the frame is a main operating shaft Q-equipped at one outer operation of the machine,'inasmuch as the machineis'especially designed as a manuallyoperated .machine. Located adjacent to the inner faces of thehead plates 7 and rigidly end with. an operating crank 10 for hand secured mama 9 for rotation therewith are spider-like head brackets 11 further tied tob gether by rods 12 and 13. These head brackets carry a detachably applied type segment 14 that carries replaceable type 15 for the printing of letters, circulars or the like according to the set-up of the type on the segment. j

The segment l t in the machine illustrated extends through approximately degrees,

leaving an open space in the other 180 degrees inwhich 18 mounted ribbon rolls 16 and 17,

thestuds l6 and 17 of which are journaled in of'the rotaryhead brackets 11. I

. fThe type-equippedsegment 14 co-operates with a platen roller 18, the shaft 18 of which'is journaled in the base 6 and the top ribbon-feeding actions. Reverse'ly acting of which roller works through and opens in said base. The shaft 18 is provided at one end with a small spur gear 19 that meshes with a large annular spur gear 20 carried by one of the rotary head brackets 11. The sheet of paper 3 that is to be printed is fed over the platen roller 18 by co-operating lower and upperfeed'rolls 21 and 22, the-shaft 21 of which former is journaled in the base 6 and is provided at one end with a spur pinion 23 that is connected to. the gear-=19 by a small intermediate gear or pinion 24 suitably journaled on the base6.

The inked ribbon 25 is passed over the exposedface of the typed-5' audits ends are reversely wound on the. ribbon rollers 16 and "17,as best shown inFig. 1. The studs 16 and 17 respectively, are equipped with ratchet wheels 26and27, seeFlgs. 1 and 4, the teeth :of which are arranged for reverse feed dogs or pawls.28 and 29, co-operate with the ratchet wheels 26 'andx27, respectively.

The'mechanism so far .described'in connection with the drawings is the structure of the so-called Gammeter printerN'o. 36 above furthat imparts reciprocating movements ther identified; and in said machine.there is further an eccentrically actuated member to'the dogs 28 and 29 during l8O degrees of move- 'ment'thatitheprinting segment is out of action and, moreover, said machine comprises a device for automatically shifting the two dogs '28an d 29 Lilternately'into' action as the ribbon is wound substantially from the one roll to the other. The automatic shifting action above noted is not aipa-rt of'the'present invention.

The means hitherto employed forreciprocating the dogs '28 and 29 could and did impart but one step of movement, to wit: about athree-eigliths inch movement to the ribbon "foreach coniplete'rotation and resulting operation of the printing segment and under which -act1on,of course, the type press the ribbon'agai-nst'the' paper sheet to be printed.

This invention,"as already indicated in a general way, is dirccted to improved ribbon feeding means whereby'a plurality of steps of movementwvill be imparted to'the ribbon for each printing operation. "As a preferred "means for carrying out this improved feeding'movement, a ea-m plate 30 is rigidly secured to the inner face of one of the fixed frame head plates? This cam plate when -designedas an attachment for means new in use will be made as a separate element readily applicable to thesaidframe head plate; but in the designing'of new machines,-said 'cam plate would naturallyand preferably be cast integral withthe head plate to which it is applied. As'bestshown in'-Fig."3, cam plate 30 is provided with a. profile cam-way '31" which, throughout about180 degrees, ex-

tends concentrictoithe axis of shaft 9 and carriershown as in the form of a flat sliding bar 32, to the intermediate portion of which the pawls 28 and 29 are pivotally attached. At its inner end, pawl carrier slide is formed with an elongated loop 32 that slides on the concentric hub 30 of cam plate 30. To guide the outer end of pawl carrier 32 for straightrline radial movement, it 1s as shown,

provided with a laterally projected lug 32 that slides on a radialguide rod rigidly secured to the adjacent rotary head bracket 11. 'Pawl carrier 32 is provided with a laterally projecting roller equipped stud 32.

As already indicated, the means for alternately shifting the dogs 28 and 29 into action when the ribbon is nearly wound from one roll to-another is apart of. the machine above identified and not here illustrated or described in. detail. It is sufficient for the un clerstanding of this case to state that one on the other of the dogs 28 01729 will always be in action to wind the ribbon in the one direct1on'or the other onto the receivmg and oil from the delivery roll. WVith the cam-acting device described, it is evident that between each printing operation the pawl carrier 32 will be given three complete in and out movements. In the particular arrangement illustrated, outward movement of the pawl carrler will simply .give the operative pawl a new grip on its oo-operating ratchet wheel while return or inward movement will impart movement to the ribbon roll and hence to the ribbon. WVith the above described arrangement for each printing action the ribbon will, for example be given three steps of move- 'ment, each step being three-eighths of an inch and the three steps giving to the ribbon nlneeighths or one inch and an eighth of a movement' for each printing operation. Now, assuming that'the extent of the printing type is approximately or slightly less than 180 degrees in circumferential extent, then completely new ribbon surface will be exposed to all printing operation of the entire segment following each five printing movements, whereas with the single step movement hitherto used, new ribbon surface would be presented to the said type only once every fifteen or more printing operations. In prac-. .tice it has been found, as already indicated, that whereas much as approximately fifteen printing operations are produced, some of the printed matter on a printed sheet will bemuch dimmer or lighter than other portions .rlid

thereof, thereby producing a very great unevenness in the printing of any particular sheet. It has been found that with the improved feed mechanism whereby the ribbon feed movement is increased or accelerated, the printing on any particular sheet will be uniform and as this is obvious, it is highly important in the reproduction of duplicates.

Moreover, the device described may with very slight change and with very small cost be incorporated in duplicating or reprinting machines either in the initial process of manufacture or as an attachment to machines already in use. Also from what has been said, it will be understood that the invention described is capable of various modifications within the scope of the mvention hereln disclosed and claimed.

lVhat I claim is:

1. In a machine of the class described wherein a ribbon and co-operating type are employed to produce the printing actions, means for intermittently bringing the type and ribbon into printing operation of a printreceiving sheet, and means for automatically producing a plurality of ribbon-feeding movements between successive printing operations.

2. In a machine of the class described, a rotary type-equipped segment, a ribbon extended over the type, ribbon rolls rotatable with said type segments, and automatic machine-actuated ribbonfeeding mechanism constructed and arranged to imparta plurality of ribbon feeding-movements to said rolls and ribbon between successive printing operations.

3. In a machine of the class described, a rotary type-equipped segment, a ribbon extended over the type, ribbon rolls rotatable with said type segments, pawl and ratchet ribbon-feeding devices operative on said ribbon rolls, a reciprocating pawl carrier, and a plural-acting cam operative to impart a plurality of operating movements to said pawl carrier between successive printing operations.

4. In a machine of the class described, a

rotary type-equipped segment, a ribbon extended over the type, ribbon rolls rotatable with said type segments, ratchet wheels connected to the respective ribbon rolls, pawls co-operating with the respective ratchet wheels, a reciprocating pawl. carrier and pawls being carried with said rotary type segment, and a cam fixed on the machine frame and having a plurality of cam-acting which said cam is an element formed independently of but attached to the main frame.

7. The structure defined in claim 4 in which said cam is operative on said pawlcarrier throughout the printing movement to hold the same against ribbon-feeding move ment.

8. The structure defined in claim 4 in which said pawl carrier is guided on fixed machine elements for straight-line movement radiating from the axis of rotation of said type segment.

9. The structure defined in claim 4 in which i said cam plate has a profile cam-way extending throughout approximately 180 degrees concentric to the axis of rotation of said type segment and in the other 180 degrees has a' plurality of inwardly and outwardly extended cam surfaces, said pawl carrier having a laterally projecting stud that works in said cam-way.

In testimony whereof I aifix my signature.

PERCY R. SEWARD.

portions operative on saidpawl carrier to impart thereto a plurality of complete ribbonfeeding movements between successive printing operations.

5. The structure defined in claim 4 in which the ratchet wheels and pawls co-operating with the different ribbon rolls arranged for

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