US3138092A - Selective printing arrangements for rotary printing or duplicating machines - Google Patents

Description

June 23, 1964 3,138,092

A. E. BLOCK SELECTIVE PRINTING ARRANGEMENTS FOR ROTARY PRINTING 0R DUPLICATING MACHINES Filed Dec. 15, 1958 3 Sheets-Sheet 1 VEN TOR 41min [IF/V657 54 00 ATTORNE Y June 1964 A. E. BLOCK 3, 38,092

SELECTIVE PRINTING ARRANGEMENTS FOR ROTARY PRINTING OR DUPLICATING MACHINES Filed Dec. 15, 1958 s Sheets-Sheet 2 IN VEA/ TI'O/Z A L pe p f/VEJT 152 06% A TTORNE Y June 1964 A. E. BLOCK SELECTIVE PRINTING ARRANGEMENTS FOR ROTARY PRINTING OR DUPLICATING MACHINES 15, 1958 3 Sheets-Sheet 3 Filed Dec.

IN VE N TOR BY I \Q/MJJW ATTORNISY United States Patent Ofiiice 3,138,092 Patented June 23., 1964 3,138,092 SELECTIVE PREN IlNG ARRANGEMENTS FOR ROTARY PRINTING R DUPLICATING MACHINES Alfred Ernest Block, Hammersmith, London, England,

assignor to Block 8: Anderson Limited, London, England, a British company Fiied Dec. 15, 1%8, Ser. No. 780,355 Claims priority, application Great Britain Dec. 19, 1957 8 Claims. (Cl. 10191) The present invention relates to rotary machines for effecting selective printing or duplicating and is more particularly, although by no means exclusively, applicable to machines which are adapted to take copies of one or more selected text lines from a hectographicmaster sheet or other equivalent printing form which includes a plurality of spaced text lines thereon.

Heetographic duplicating machines of the general type referred to above usually comprise a printing couple consisting of a printing drum and a co-operating counterpressure roller, the hectographic master being effectively wrapped round the surface of the printing drum and the copy sheets being fed to the bight between such drum and the counterpressure roller after that surface of the copy sheet which is to contact the image-bearing surface of the master has been moistened with a solvent for the hectographic ink of such master.

In co-pending application No. 755,763 of August 19, 1958, now US. Patent No. 3,035,517 (hereinafter called the earlier application), there is described a number of arrangements whereby selective copying may be simply and expeditiously effected from one or more of the text lines of a master sheet which is so carried upon the printing drum that its text lines are disposed parallel to the drum axis. Such arrangements were characterised by the subdivision of at least a part of the working peripheral surface of the printing drum into a number of separate printing segments each of which was individually displaceable in a radial direction relative to the drum axis between an inward, inoperative, position and an outward, printing, position.

With such selective printing arrangements, some difiiculty is encountered at times by reason of changes in the effective circumferential distance around the printing drum, measured from the clip or like means at the head of the master image, such changes occurring with different numbers and positions of the displaced printing segments and tending to produce some degree of misalignment of the operative segments with the related text line or image zone of the master image especially towards the trailing end of the latter.

An object of the present invention is to effect an improvement in or modification of such general type of machine which provides improved registration between the printing image and the selective printing members and which also results in a simplified construction and improved operating characteristics.

In accordance with the invention, a rotary printing or duplicating machine which includes a rotatable drum adapted to carry around its peripheral surface a printing image having text lines or similar image zones disposed parallel with the drum axis and a co-operating pressure roller rotatable about an axis parallel with that of said drum for impressing a copy sheet against said printing image at the printing bight between said drum and roller, has at least a part of the peripheral surface of said counterpressure roller subdivided into a plurality of separate pressure segments each of which is individually displaceable in a radial direction between an inward, inoperative, position and an outward, impression-producing, position, said counterpressure roller being in geared driving connection with said drum at least during that part of each revolution of said roller when any one of said pressure segments is passing through the printing bight so as to rotate at the same peripheral speed of said drum, and is provided with preselection means for effecting the individual positioning of each of said pressure segments in either its outward, operative, or inward, inoperative, position whilst passing through said printing bight in accordance with the required pattern of item or line selection from said printing image.

In order that the nature of the present invention may be more readily understood, a number of practical embodiments thereof will now be described with reference to the accompanying drawings, in which:

FIG. 1 is a fragmentary vertical sectional view, taken on the line I-I of FIG. 2 in a plane normal to the respective axes of the printing drum and counterpressure roller, of part of a hectographic duplicating machine incorporating the invention.

FIG. 2 is a part-sectional, part-eievational view of the arrangements of FIG. 1, taken on the line IIII of FIG. 1.

FIG. 3 is a largely diagrammatic cross-sectiona1 view, similar to FIG. 1, showing a modified construction.

FIG. 4 is a fragmentary end elevational view of the rintin g drum and counterpressure roller of another modification.

FIG. 5 is an enlarged detail view illustrating a part of the embodiment of FIG. 4.

FIG. 6 is a largely diagrammatic fragmentary view showing yet a further alternative form of the invention.

FIGS. 1 and 2 of the drawings show one embodiment of the invention as applied to a spirit duplicator having a printing drum 10 rotatably mounted on a fixed axle 11 extending between opposite side plates 12, 13 of the machine frame. The drum 10 is provided with the usual securing clip 14 for the master sheet M carrying the printing image in hectographic ink thereon, but otherwise its cylindrical peripheral surface extends uninterruptedly at a constant radius around the whole of the circumference. For improving the impression characteristics of the printing couple in view of the particular form of the counterpressure roller to be described later, the major part of the surface of the drum It? is preferably provided with a slightly resilient surface layer 15, e.g. of rubber or plastic.

The drum 19 is arranged for rotation by any convenient known means such as, as shown, by a manually operable crank handle 16 through a 2:1 speed reduction drive of gear wheel 17 secured to the spindle of the handle 16 in constant mesh with a gear wheel 18 rigidly secured to one end wall of the drum 19.

The counterpressure roller, shown at 19, is journalled upon a fixed tubular axle 20 which is carried at each end in rotatable eccentric bushings 21 secured to the side plates 12, 13 for the purpose of allowing adjustment of the spacing distance between the drum 10 and counterpressure roller 19 at the printing bight P and thereby altering the printing pressure exerted between the copy sheet CS and the master M in well-known manner.

Associated with the printing couple of the drum l0 and roller 19 are the usual sheet feeding and damping rollers 22, 23 also journalled in the side plates 12., 13 for effecting initial transmission and moistcning of the upper surface of the copy sheet CS with solvent fluid during its passage from the sheet supply position to the printing bight P. The sheet CS is conveyed over support plates 24 and through intermediate sheet feeding and holding means in the form of a further rotatable roller 25 on the underside of the sheet and retaining balls 26 on the upper side of the sheet.

The counterpressure roller 19 in this embodiment is of the same effective radius as that of the drum and is positively driven from such drum through gear wheels 27, 28 having a 1:1 drive ratio and secured respectively to the drum and roller. The detailed construction of the roller 19 closely resembles that of the printing drum as described in the aforesaid earlier application in that a major part of its peripheral surface is subdivided into a number of pressure segments 29 each of a circumferential width equal to one of the individually selectable text line regions of the master M. Each segment 29 is provided with a thin inwardly-directly web 30 which is supported, in a manner permitting both axial and radial movement, within a series of radial slots 31 in the edge regions of spaced support plates 32 which are rigidly secured to hearing bushes 33 rotatable upon the fixed axle 20. Each segment 29 is resiliently retained in position and urged radially inwards by means of springs 34 extending between each web 30 and plates 35 secured to each bush 33. Each web 30 is provided with a number of notches 36 along its inwardly directed edge and these co-operate with fixed position shift rollers 37 carried in a support collar 38 which is secured in non-rotatable manner to the fixed axle 20.

As shown at the right-hand side of FIG. 2, each segment 29 has an outwardly-directed nose 39 which, when the counterpressure roller 19 and printing drum 10 are in a given datum or start position, lies opposite to an associated one of a series of interposer lugs 40 of which only one is shown. Each lug 40 is carried by an individual plunger 41 itself reciprocable within a radial guide channel 42 in an arcuate body 43 mounted on slide rods 44 secured to the side plate 13 in a manner which permits movement of the body 43 towards and away from the adjacent end of the counterpressure roller 19. The position of each interposer lug 40 can be individually controlled from a remote keyboard in a manner similar to that described in the aforesaid earlier application by means of a Bowden cable 45 or like means so as to be either in the inward position shown in full lines in FIG. 2 or in the outward position shown in chain-dotted lines.

The body 43 is arranged to be reciprocated, first towards and then away from the roller 19, conveniently in the manner described in the earlier application, during each setting operation and after positioning of the lugs 40 so that the lug corresponding to each text line which is required to be printed is moved to its inward position whereas the remaining lugs are held in their outward positions. By such reciprocatory movement each inwardlydisplaced lug 40 engages the opposing nose 39 and shifts the associated segment 29 axially to the left, FIG. 2. This causes the notches 36 in the web 30 of each of such displaced segments 29 to become out of register with the shift rollers 37. The notches 36 in the unshifted seg ments remain in register with such rollers.

The drum 10 and roller 19 are now caused to rotate in unison to carry the master M through the bight zone P. As each unshifted pressure segment 29 on the counterpressure roller 19 moves into the printing bight P, the notches 36 in its web 30 will be in alignment with the shift rollers 37 whereby such rollers pass through the notches and do not affect the position of the pressure segment which remains continuously in its inward or inoperative state. The wide gap in the printing bight P results in separation of the copy sheet CS from the master M whereby the copy sheet is not drawn forwardly and no printing impression is taken from the zone or zones of the master which are then passing through the bight P.

Upon the approach into the bight P of any pressure segment 29 which has been moved axially during preselection, the shift rollers 37 engage the full depth of the webs 30 so that, as shown in FIG. 1, such pressure segment is moved radially outwards to a position where, as it passes the bight P, it exerts printing pressure upon the copy sheet CS against that portion of the master M which then lies opposite the segment. The copy sheet CS is drawn forwardly at the same time. Subsequently, as the segment moves past the rollers 37 it withdraws inwards again and no further printing or forward movement of the copy sheet takes place until the arrival of the next selected and shifted pressure segment.

The pressure segments 29 of the counterpressure roller 19 may each be divided into two or more parts for the purpose of allowing controlled selection of the Width of the printed portion of each selected line in a manner analogous to that described in said earlier application while the counterpressure roller may likewise be provided with means for moving all of the pressure segments to the outward position simultaneously so as to provide the equivalent of a normal constant radius pressure roller.

The counterpressure roller in the embodiment just described is necessarily of the same effective diameter as that of the printing drum, since it is positively interconnected for simultaneous and continuous rotation at the same peripheral speed. Since, in the case of application to a hectographic duplicating machine as described, only a part of the total circumferential dimension of the printing drum is normally usable for supporting the printing zone of the master, only a corresponding arc of the counterpressure roller need be subdivided into separate pressure segments.

The use of a counterpressure roller of the same, relatively large, diameter as the printing drum can be some what disadvantageous in practical machine designs and as an alternative it is possible, as shown schematically in FIG. 3, to reduce the counterpressure roller diameter by subdividing the Whole of its circumferential wall into separate pressure segments, the number of pressure segments being made equal to the maximum number of separate text lines or equivalent zones on the associated master. In this modification an interrupted toothed gear wheel 47 secured to the printing drum 10 drives the gear wheel 28 secured to the counterpressure roller 19 whereby the latter rotates with the same peripheral speed as the printing drum 10 during that part of each revolution when the image-bearing region of the master is passing through the printing bight and then, after completing exactly one revolution, remains stationary while the printing drum 10 completes the rest of its single revolution.

In a further and preferred arrangement, the counterpressure roller is made of substantially smaller diameter than the printing drum, for example, about one third or one quarter of the drum diameter, and the whole of its peripheral zone is subdivided into equal-width pressure segments. The necessary control of the inward and outward radial movement of such segments is then transferred from the counterpressure roller to the printing drum itself, since the counterpressure roller now makes more than one revolution for each revolution of the printing drum and each pressure segment will be opposed to several ditferent image lines or zones of the single master.

One arrangement of this kind is illustrated in FIGS. 4 and 5 where the counterpressure roller 19 has pressure segments 29 around the whole of its periphery and each of these are mounted as before for both axial and radial movement in supporting plates 32 carried upon a structure rotatable about the fixed axle to which is rigidly secured the bushings supporting the shift rollers 37. In this embodiment each pressure segment 29 is resiliently urged both towards its radial inward position and towards the right-hand (FIG. 5) end of the roller 19 by springs 48 as shown in FIG. 5 extending between each segment web 30 and anchor plate 35. Each segment 29 is provided at its-x ight-hand end with a projecting nose piece 39 having a rounded end. On the associated printing drum 10, in alignment with each text line position or equivalent image zone, there is provided a radially displaceable striking plate 49 secured to the end wall 50 of the drum by screws 51 passing through slots 52 in the plate whereby such plate can be moved in a direction radial to the drum axis between a first, inward, position where the cam-faced outer end 53 of the plate will pass clear of any projecting nose piece 39 and a second, outward, position where such outer end 53 will engage such nose piece 39 during the joint rotation of the drum 1d and counterpressure roller lll due to their continuous interconnection through gear wheels not shown. Such engagement will cause axial movement of the associated segment 29 leftwards (FIG. 5) with respect to the rest of the counterpressure roller structure whereby the slots at in its web are out of alignment with the shift rollers 37 with the result that such segment is moved radially outwards during the time of its passage through the printing bight P to press the copy sheet CS upon the master image carried by the printing drum and the copy sheet moved forwards at the same time. The leading edge of each striking plate 4-9 is provided with a chamfered or cammed lip edge while, preferably, the rearward or trailing edge of such striking plate is shaped as shown in FIG. 4, whereby it releases the associated nose piece 39 immediately after the associated segment 29 has passed the printing bight so as to allow the latter to move axially to the right (FIG. 5) and thereby to return rapidly to its inward or inoperative position.

For the purpose of pre-setting the position of each striking plate 4-9, the latter is provided with a further aperture 5'4 between the slots 52 for co-operating with a slida'ole setting cam element 55 which is movable Within an axially directed slot in the end Wall 54 of the printing drum lit The outer end of each cam element 55 has a head 56 for engagement with a displaceable setting plunger 57 carried in the side plate 13. A plurality of such setting plungers are provided, one for each striking plate 49, in positions which align with the heads as when the printing drum It) is in a datum or start position. Each plunger 57 is operatively connected to suitable control means such as a conhot key on a keyboard, by suitable means, for instance, a Bowden cable. By operating such keys, any required one or group of striking plates 49 can be displaced from their normal, inward, to the outward position.

At the opposite end within the printing drum, each cam element 55 is provided with a further axially directed projection 5b which is engaged by a resetting disc 59 when this is moved, by a reset control member not shown, axially of the printing drum from the position shown in full lines in FIG. 5 to that shown in chain-dotted lines. This resets any displaced cam element and returns the associated striking plate 49 to its normal inward position.

in operation, the cam elements 55 corresponding to the required text lines or zones of the printing drum are first displaced by operation of the control means. This causes corresponding radial outward movement of the associated striking plates 49 around the edge of the printing drum ill. When the latter is subsequently rotated in unison with the counterpressure roller 19, those striking plates which have been displaced each engage with the nose piece 39 of the opposing segment 29 as they each approach the printing bight and so move the pressure segment axially. The resultant positioning of the associated web notches 36 out of register with the shift rollers 37 causes radial outward movement of the segment to effect the required printing impression whereafter it is promptly returned to its inward inoperative position by the release of the nose piece 39 from beneath the striking plate to avoid undesired further movement of the copy sheet CS and any smudging thereof by unwanted parts of the master image.

Various other methods of constructing the device will be apparent to those skilled in the art. F or example, selection of the appropriate pressure segments may be effected by a cam-faced abutment which is controlled electrically as shown in FIG. 6. Here each pressure segment 29 has a nose piece 39 similar to the device of FIGS. 4- and 5. In the path swept through by each nose piece during rotation of the roller 19 is located a cam-faced abutment 6d secured to one end of an operating rod s1 which carries the armature 62 of a solenoid 63 secured on the outer surface of the side plate 13. Around a peripheral edge of the printing drum is provided a series of separate contact plates 64 resembling a commutator, there being one plate for each text line or equivalent image zone. A contact brush 65 cooperating with the contact plates 64 is connected in series with the winding of the solenoid 63 and one terminal of a source of operating current, the opposite terminal of the latter being arranged for selective connection through a group of preselecto-r switches 66 to the individual contact plates 6d.

In operation, as any connected contact plate 64 engages the brush es, the solenoid 63 is energised, the cam-faced abutment 64) is displaced inwardly to the operative position shown in chain-dotted lines as a result of which the nose piece 39 of the opposing pressure segment 29 is engaged and the segment moved axially whereby the notches in its associated web become out of alignment with the shift rollers 37 and the segment is moved outwards to the operative or printing position while it passes through the printing bight. Immediately afterwards the circuit is broken by movement of the particular contact plate as from beneath the brush 65, the solenoid 63 is deenergised and the cam-faced abutment as is returned to its inoperative position and with it the operated segment "5 Although the invention has been described in its particular application to hectographic duplicating machines, it will be apparent that it may also be applied with advantage to other forms of rotary printing or duplicating machines including stencil duplicators, offset printing machines and rotary type cylinder machines for the purpose of effecting selective printing. Thus, in the case of offset printing a cylinder resembling that of the counterpressure roller described above may be provided for cooperation with the blanket roller while in the case of a rotary cylinder machine employing a cylinder or partcylindrical relief printing surface a similar roller may be arranged for co-operation therewith to effect selective printing. Such adaptation may call for selective inking co-related to the selective printing Zones and for this purpose an inking roller of broadly similar character, is. with radially displaceable segments, may be employed or alternatively use may be made of an inking roller arranged to execute appropriately timed movements into and out of contact with the printing surface.

I claim:

1. A rotary printing or duplicating machine which comprises a rotatable drum, image securing means on said drum for securing around the peripheral surface of such drum a printing image having a plurality of juxtaposed text lines or similar image zones of predetermined and equal unit depth and each extending parallel with the drum axis, each of said text line zones being in register with a related predetermined area of the drum surface, a counterpressure roller co-operating with said drum and rotatable about an axis parallel with that of such drum for impressing a copy sheet against said printing image at the printing bight between said drum and roller, at least a part of the peripheral surface of said counterpressure roller being subdivided into a plurality of separate pressure segments, each of said segments being immovable circumferentially with respect to the remainder of said roller and extending axially of said roller for a distance at least equal to the maximum width of a copy sheet and having a common circumferential width equal to said unit depth dimension of said printing image text line zones, means mounting each of said pressure segments for individual movement bodily in a radial direction with re spect to the axis of said roller between an inward, inoperative, position where the outward facing surface thereof is spaced from said peripheral drum surface and said printing image while passing through said bight and an outward impression-producing, position where said outward facing surface will impress said copy sheet against said printing image while passing through said bight, gear means providing geared driving connection between said drum and said roller at least during that part of each revolution of said drum when any one of said text line Zones is passing through the printing bight, said geared driving connection providing registration of the outwardly facing surfaces of each pressure segment with a diiferent one of said text line zones while passing through the printing bight and preselection means for effecting the individual positioning of each of said pressure segments in either its outward or its inward position while passing through said printing bight in accordance with the required pattern of text line zone selection from said printing image, said preselection control means including a plurality of first members, one for each of said image zones of said printing image, mounted on said drum at angularly spaced positions related respectively to said different image zones and a plurality of second members, one on each of said pressure segments of said counterpressure roller, each of said first members when rendered effective by preselection to position a related pressure segment in its outward position bein operative upon one of said second members to cause radially outward movement of the associated pressure segment while said segment is located in the printing bight.

2. A rotary printing or duplicating machine which comprises a rotatable drum of constant predetermined radius, image securing means on said drum for securing around the peripheral surface of such drum a printing image having a plurality of text lines or similar image zones of predetermined and equal unit depth and each extending parallel with the drum axis, each of said text line zones being in register with a related predetermined area of the drum surface, a counterpressure roller cooperating with said drum and rotatable about an axis parallel with that of such drum for impressing a copy sheet against said printing image at the printing bight between said drum and roller, at least a part of the peripheral surface of said counterpressure roller being sub-divided into a plurality of separate pressure segments being immovable circumferentially with respect to the remainder of said roller and, each of said segments extending axially of said roller for a distance at least equal to the maximum width of a copy sheet and having a common circumferential width equal to said unit depth dimension of said printing image text line zones, means mounting each of said pressure segments for individual movement bodily in a radial direction with respect to the axis of said roller between an inward, inoperative, position lies at a radius from the roller axis which is less than said drum radius and where the outward facing surface thereof is spaced from said peripheral drum surface and said printing image while passing through said bight and an outward, impression-producing, position lies at a radius from the roller axis equal to said drum radius and where said outward facing surface will impress said copy sheet against said printing image while passing through said bight, gear means providing a one-to-one and continuous geared driving connection between said drum and said roller whereby the outwardly facing surfaces of each pressure segment register with a different one of said text line zones while passing through the printing bight and preselection means for effecting the individual positioning of each of said pressure segments in either its outward or its inward position while passing through said printing bight in accordance with the required pattern of text line zone selection from said printing image, said preselection control means including a plurality of first members, one for each of said image zones of said printing image, mounted on said drum at angularly spaced positions related respectively to said different image zones and a plurality of second members, one of each of said pressure segments of said counterpressure roller, each of said first members when rendered effective by preselection to position a related pressure segment in its outward position being operative upon one of said second members to cause radially outward movement of the associated' pressure segment while said segment is located in the printing bight.

3. A rotary printing or duplicating machine which comprises a rotatable drum of constant predetermined radius, image securing means on said drum for securing around the peripheral surface of such drum a printing image having a plurality of juxtaposed text lines or similar image zones of predetermined and equal unit depth and each extending parallel with the drum axis, each of said text line zones being in register with a related predetermined area of the drum surface, said printing image extending around the periphery of said drum for a circumferential distance less than the total circumference of the drum, a counterpressure roller co-operating with said drum and rotatable about an axis parallel with that of such drum for impressing a copy sheet against said printing image at the printing bight between said drum and roller, said roller having a circumference equal to the circumferential distance around said drum covered by said printing image, the peripheral surface of said counterpressure roiler being wholly sub-divided into a plurality of separate pressure segments, each of said segments extending axially of said roller for a distance at least equal to the maximum width of a copy sheet and having a common circumferential width equal to said unit depth dimension of said printing image text line zones, means mounting each of said pressure segments for individual movement bodily in a radial direction with respect to the axis of said roller between an inward, inoperative, position where the outward facing surface thereof is spaced from said peripheral drum surface and said printing image while passing through said bight and an outward, impression-producing, position where said outward facing surface will impress said copy sheet against said printing image while passing through said bight, gear means providing intermittent geared driving connection between said drum and said roller for rotating said roller at the same peripheral speed as said drum during that part of each revolution of said drum when any one of said text line zones is passing through the printing bight, said geared driving connection providing registration of the outwardly facing surfaces of each pressure segment with a different but related one of said text line zones while passing through the printing bight, said roller remaining stationary during the remainder of each complete revolution of said drum, and preselection means for effecting the individual positioning of each of said pressure segments in either its outward or its inward position while passing through said printing bight in accordance with the required pattern of text line zone selection from said printing image.

4. A rotary printing or duplicating machine which comprises a rotatable drum of constant predetermined radius, image securing means on said drum for securing aroiiiid the peripheral surface of such drum a printing image having a plurality of juxatposed text lines or similar image zones of predetermined and equal unit depth and each extending parallel with the drum axis, each of said text line zones being in register with a related predetermined area of the drum surface, said printing image extending around the periphery of said drum for a circumferential distance less than the total circumference of the drum, a counter-pressure roller co-operating with said drum and rotatable about an axis parallel with that of such drum for impressing a copy sheet against said printing image at the printing bight between said drum and roller, said roller having a circumference equal to the circumferential distance around said drum covered by said printing image, the peripheral surface of said counterpressure roller being wholly sub-divided into a plurality of separate pressure segments, each of said segments extending axially of said roller for a distance at least equal to the maximum width of a copy sheet and having a common circumferential width equal to said unit depth dimension of said printing image text line zones, means mounting each of said pressure segments for individual movement bodily in a radial direction with respect to the axis of said roller between an inward, inoperative, position where the outward facing surface thereof is spaced from said peripheral drum surface and said printing image while passing through said bight and an outward, impression-producing position where said outward facing surface will impress said copy sheet against said printing image while passing through said bight, gear means providing intermittent geared driving connection between said drum and said roller for rotating said roller at the same peripheral speed as said drum during that part of each revolution of said drum when any one of said text line zones is passing through the printing bight, said geared driving connection providing registration of the outwardly facing surfaces of each pressure segment with a different one of said text line zones while passing through the printing bight, said roller remaining stationary during the remainder of each complete revolution of said drum, means retaining said pressure segments normally in their inward, inoperative, positions, preselection means for selecting chcosen ones of said pressure segments for outward movement to the impression-producing position in accoradnce with the required pattern of text line zone selection from said printing image and means operative to move each selected pressure segment radially outwards to the impression producing position as it approaches the immediate vicinity of the printing bight and to allow said pressure segment retaining means to withdraw such selected pressure segment to its normal inward position immediately as it leaves such printing bight.

5. A rotary printing or duplicating machine which comprises a rotatable drum, image securing means ,on said drum for securing around the peripheral surface of such drum a printing image having a plurality of juxtaposed text lines or similar image zones of predetermined and equal unit depth and each extending parallel with the drum axis, each of said text line zones being in register with a related predetermined area of the drum surface, said drum having a constant radius such that its circumference is an exact multiple of said unit text line depth dimension, a counterpressure roller co-operating with said drum and rotatable about an axis parallel with that of such drum for impressing a copy sheet against said printing image at the printing bight between said drum and roller, said roller having a radius substantially less than that of said printing drum and having the whole of its peripheral surface sub-divided into a plurality of separate pressure segments, each of said segments extending axially of said roller for a distance at least equal to the maximum width of a copy sheet and having a common circumferential width equal to said unit depth dimension of said printing image text line zones, means mounting each of said pressure segments for individual movement bodily in a radial direction with respect to the axis of said roller between an inward, inoperative, position where the outward facing surface thereof is spaced from said peripheral drum surface and said printing image while passing through said bight and an outward, impressionproducing, position where said outward facing surface will impress said copy sheet against said printing image while passing through said bight, gear means providing a continuous geared driving connection between said drum and said roller for rotating said roller at the same peripheral speed as said drum and providing registration of the outwardly facing surfaces of each pressure segment with a different one of said text line zones while passing through the printing bight and a plurality of preselectable control means, one for each of said text line zones, for effecting the individual positioning of each of said pressure segments in either its outward or its inward position in accordance with the required pattern of text line zone selection from said printing image, said preselectable control means being mounted on said printing drum each in alignment with a related text line zone and being operative upon said pressure segments in turn during the periods when such zone and the related pressure segment are passing through the printing bight.

6. A rotary printing or duplicating machine according to claim 5, in which each of said displaceable pressure segments is movable axially as well as radially and in which said preselectable control means comprise cam elements arranged to cause axial displacement of the related pressure segments immediately prior to the passage of such segments through the printing bight and stationary radial shift means arranged to be engaged by each of said displaced segments to move it from its inoperative to its operative position while in said printing bight.

7. A rotary printing or duplicating machine according to claim 6, in which said cam elements carried by said printing drum comprise individual radially movable members, one for each selectable text line or printing zone, said members being themselves displaceble between an inoperative inward position and an outward operative position and line selection mechanism arranged to control the positioning of said radially movable members.

8. A rotary printing or duplicating machine according to claim 6, in which said preselectable control means include a plurality of circumferentially spaced electric contact elements, one of each selectable text line or printing Zone, mounted on said printing drum, a displaceable cam-faced abutment arranged for controlled engagement with said pressure segments as they pass through the printing bight, electromagnetic means for displacing said abutment from an inoperative to an operative position and a control circuit including selector switch means, one for each of said contact plates, for establishing an energising supply path to said electromagnetic means to cause said abutment to be moved into its operative position only when each of the pressure segments: corresponding to the selected text lines is passing through said printing bight.

References Cited in the file of this: patent UNITED STATES PATENTS 469,931 Briggs Mar. 1, 1892 867,868 Beals Oct. 8, 1907 1,196,729 Barroll Aug. 29, 1916 1,744,770 Jahn 1 Jan. 28, 1930 2,012,670 Mack Aug. 27, 1935 2,034,208 Ritzerfield Mar. 17, 1936 2,250,534 Higgins et al July 29, 1941 2,307,264 Hamlin Jan. 5, 1943 2,421,823 Allen et a1. June 10, 1947 2,753,791 Thurmann July 10, 1956 3,035,517 Bonsch May 22, 1962 FOREIGN PATENTS 409,321 Italy Feb. 12, 1945

Claims (1)

1. A ROTARY PRINTING OR DUPLICATING MACHINE WHICH COMPRISES A ROTATABLE DRUM, IMAGE SECURING MEANS ON SAID DRUM FOR SECURING AROUND THE PERIPHERAL SURFACE OF SUCH DRUM A PRINTING IMAGE HAVING A PLURALITY OF JUXTAPOSED TEXT LINES OR SIMILAR IMAGE ZONES OF PREDETERMINED AND EQUAL UNIT DEPTH AND EACH EXTENDING PARALLEL WITH THE DRUM AXIS, EACH OF SAID TEXT LINE ZONES BEING IN REGISTER WITH A RELATED PREDETERMINED AREA OF THE DRUM SURFACE, A COUNTERPRESSURE ROLLER CO-OPERATING WITH SAID DRUM AND ROTATABLE ABOUT AN AXIS PARALLEL WITH THAT OF SUCH DRUM FOR IMPRESSING A COPY SHEET AGAINST SAID PRINTING IMAGE AT THE PRINTING BIGHT BETWEEN SAID DRUM AND ROLLER, AT LEAST A PART OF THE PERIPHERAL SURFACE OF SAID COUNTERPRESSURE ROLLER BEING SUBDIVIDED INTO A PLURALITY OF SEPARATE PRESSURE SEGMENTS, EACH OF SAID SEGMENTS BEING IMMOVABLE CIRCUMFERENTIALLY WITH RESPECT TO THE REMAINDER OF SAID ROLLER AND EXTENDING AXIALLY OF SAID ROLLER FOR A DISTANCE AT LEAST EQUAL TO THE MAXIMUM WIDTH OF A COPY SHEET AND HAVING A COMMON CIRCUMFERENTIAL WIDTH EQUAL TO SAID UNIT DEPTH DIMENSION OF SAID PRINTING IMAGE TEXT LINE ZONES, MEANS MOUNTING EACH OF SAID PRESSURE SEGMENTS FOR INDIVIDUAL MOVEMENT BODILY IN A RADIAL DIRECTION WITH RESPECT TO THE AXIS OF SAID ROLLER BETWEEN AN INWARD, INOPERATIVE, POSITION WHERE THE OUTWARD FACING SURFACE THEREOF IS SPACED FROM SAID PERIPHERAL DRUM SURFACE AND SAID PRINTING IMAGE WHILE PASSING THROUGH SAID BIGHT AND AN OUTWARD IMPRESSION-PRODUCING, POSITION WHERE SAID OUTWARD FACING SURFACE WILL IMPRESS SAID COPY SHEET AGAINST SAID PRINTING IMAGE WHILE PASSING THROUGH SAID BIGHT, GEAR MEANS PROVIDING GEARED DRIVING CONNECTION BETWEEN SAID DRUM AND SAID ROLLER AT LEAST DURING THAT PART OF EACH REVOLUTION OF SAID DRUM WHEN ANY ONE OF SAID TEXT LINE ZONES IS PASSING THROUGH THE PRINTING BIGHT, SAID GEARED DRIVING CONNECTION PROVIDING REGISTRATION OF THE OUTWARDLY FACING SURFACES OF EACH PRESSURE SEGMENT WITH A DIFFERENT ONE OF SAID TEXT LINE ZONES WHILE PASSING THROUGH THE PRINTING BIGHT AND PRESELECTION MEANS FOR EFFECTING THE INDIVIDUAL POSITIONING OF EACH OF SAID PRESSURE SEGMENTS IN EITHER ITS OUTWARD OR ITS INWARD POSITION WHILE PASSING THROUGH SAID PRINTING BIGHT IN ACCORDANCE WITH THE REQUIRED PATTERN OF TEXT LINE ZONE SELECTION FROM SAID PRINTING IMAGE, SAID PRESELECTION CONTROL MEANS INCLUDING A PLURALITY OF FIRST MEMBERS, ONE FOR EACH OF SAID IMAGE ZONES OF SAID PRINTING IMAGE, MOUNTED ON SAID DRUM AT ANGULARLY SPACED POSITIONS RELATED RESPECTIVELY TO SAID DIFFERENT IMAGE ZONES AND A PLURALITY OF SECOND MEMBERS, ONE ON EACH OF SAID PRESSURE SEGMENTS OF SAID COUNTERPRESSURE ROLLER, EACH OF SAID FIRST MEMBERS WHEN RENDERED EFFECTIVE BY PRESELECTION TO POSITION A RELATED PRESSURE SEGMENT IN ITS OUTWARD POSITION BEING OPERATIVE UPON ONE OF SAID SECOND MEMBERS TO CAUSE RADIALLY OUTWARD MOVEMENT OF THE ASSOCIATED PRESSURE SEGMENT WHILE SAID SEGMENT IS LOCATED IN THE PRINTING BIGHT.

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