US2795186A

US2795186A - Value printing from coplanar type

Info

Publication number: US2795186A
Authority: US
Publication date: 1957-06-11
Anticipated expiration: 1974-06-11

Description

5 sheets-sheet 1 J. w. BACI-1 Er AL June 11, 1957 v VALUE PRINTING FROM coPLANAR TYPE Fi1ed oot..20. 195s wkw/ i@ n wwf. WMM. n www A @2 E Y m m/w i Q mfwmw f V 7 /V//////////7////// ////,//////M/// /Qw/ il f/ L s.. Q x l l l ln? lllllllllllll Il Hf @N f l Il 111111 ldull il 1| m HH ||||||ll| .m|m 1 Il Nlma h 31./ @u 1 m2 he ma YL 54 i \\|.\d/ 0 md /r m2 hw f E mm@ mmf mm.\v/\

m@ n m; @u Q.MQNN @n @u .w /7/ ATTORNEY June l1, 1957 J. w. BACH ET AL VALUE PRINTING FROM COPLANAR TYPE Filed oct. 20,1953

June 1l, 1957 J. w. BACH Er AL VALUE PRINTING FROM COPLANAR TYPE 5 Shets--Sheet 5 Filed 001'.. 20, 1955 mrli mr WS lNvEN'roR 5 lil ATTORNEY B. .my

June 11, 1957 J. w. BACH E-r AL VALUE PRINTING FROM coPLANAR TYPE 5 Sheets-Sheet 4 Filed Oct. 20, 1953 June l1, 1957 I J. w. BACH r AL 2,795,186

VALUE PRINTING FROM coPLANAR TYPE Filed Oct. 20. 1953 5 Sheets-Sheet 5 ATTORNEY g printer.

United States Patent] VVALUE PRINTING FROM COPLANAR TYPE John William Bach, Port Chester, N. Y., and Robert S. Frisbie, Springdale, and Joseph V. Kubovy, Stamford, Conn., assignors to Pitney-Bowes, Inc., Stamford, Conn., acorporalion of Delaware VApplication October 20, 1953, Serial No. 387,126

2 Claims. (Cl. 101269) This invention relates to value printing and especially to printing of value indicia on workpieces using substantially coplanar type.

In certain value printing devices it is the practice to have the printing die surface lie substantially in a plane and to make a print of the indicia thereon by pressing the workpiece between the printing face of the die and a substantially planar platen. While this practice has been common, and the printing results achievedtherewith have been acceptable, it is an object of this invention to print with a die having substantially coplanar type, but in such manner as to obtain printing results much superior to those heretofore achieved.

Another object of the invention is the accomplishment of. value printing using a die having substantially coplanar type, but in such manner that a progressive printingaction is effected similar to that achieved in a rotary Another object of the invention is the accomplishment ofga value printing using a die having substantially coplanar Vtype in which the die is held in a stationary printing position and the. impression is caused by pressing the workpiece between a portion of the printing face of the ydie and a roller, and rolling the roller so as to cause progressive printing contact between the various parts of the die surface and the adjacent workpiece areas while maintaining printing pressure so as to form a complete print.

While printing according to the immediately foregoing object can be accomplished by a single roller, it has been discovered that the distance of roller axis travel is an important consideration in the design of most value printingmachines and that minimum travel of the roller is essential to to the space consideration involved. Since value printing dies are conventionally elongate it is thus substantially imperative that such a single roller, if used, have a length equal to that of the printing die and roll a distance equal to the width of the printing die to maintain the travel within prescribed limits.

While distinctly improved printing results are achieved in this fashion, they may not be considered suiciently better than those derived using the conventional planar platen to warrant a design change in this regard.

According to the present invention it has beenV further discovered that short rollers equal to the width of the printingk die can be effectively used, that by employing a plurality of spaced rollers the length of the stroke of roller axis travel can be maintained well within acceptable limits, and that with an arrangement of this nature, prints of a quality markedly better than that obtainable with a planar platen can be made, especially when the workpieces are found to be of varying thicknesses over their areas, such as in printing on the face of an envelope having a letter or other contents therein.

It is accordingly an object ofthe present invention' toV provide for making imprints from'. an elongate printing die which has substantially coplanar type by placing al 'Patented June 11, 1957 workpiece between the same and a plurality of spaced rollers whose, length is about equal to the shorter dimension ofthe printing die, and traveling the rollers a distance about equal to the length of the printing die divided by the number of rollers used.

In value printing machines it is usually convenient if not essential to have the workpiece disposed in a face-upv direction when the printing is made so that the printed mark can be quickly and accurately placed with respect to the outlines of the workpiece or other preformed indicia on the workpiece surface. of the invention to provide for the printing of a Awork piece by bringing the printing die against its upper surface and eiecting printing by bringing a roller into printing pressure engagement with the lower surface, and rolling the roller along-the workpiece beneath the die-engaged area thereof.

In value printing machines it is necessary to have the printing effected in response to operation of the same operating member which causes the changes in register setting, and to this end it is still another object of the present invention to provide means whereby operation of the register driving member causes a roller to be pressed towards the surface of a printing die and to be moved along yits surfaceor the surface of an intervening workpiece in pressure contact therewith.

A further object of the invention is to provide means whereby movement of an operating member in one directi'on results in pressure of a platen roller towards theV surface of a printing die and movement of the pressed roller therealong, while return of the operating member to home position can be effected without causing a return trip of the platen roller under printing pressure conditions, so as to avoid the possibility of blurred impressions arising due to a repeat printing movement ot' the roller.

A further object of the invention is the provision in a value printing device of a movable shroud which can be lowered to guard the printing die against taking unauthorized impressions-between printing operations, and means for locking the shroud in guarding position except when the mechanism is operated in a normal manner tosimultaneously print and register.

A further object of the invention is the provision in a value printing device of means operated by a drive handle for controlling the operation of the device including a register, together with novel means simultaneously controlled by the handle for exerting a resilient pressure of the platen against the workpiece being printed to urge it into contact with the printing face of the die with the desired pressure regardless of its thickness.

A still further object of the inventiony is Vthe provision of novel means for inking the printing die, operated in concert with the other parts of the mechanism, but only over a portion of the travel of the'drive handle.

With the above and other objects in view, whicllwill appear as the description proceeds, the invention resides in the'combination and arrangement of parts and in the details of construction hereinafter described and claimed, it being understood that various changes in the precise embodiment of the invention herein disclosed may be made within the scope of what is claimed without departing from the spirit of the invention.

A preferred embodiment of the invention is illustrated in the accompanying drawing, wherein:

Fig. 1 is a right side elevation, partlyin section, of a value printing mechanism according to the present invention, with parts broken away to show the struc-ture and mounting of the roller-platen. y

device of Fig. 1.

It is therefore another object Fig.` 4 is a diagrammatic elevation, partly in` section,4

of the device of Fig. 3 illustrating `the various positions of the platen operating mechanism.

Fig.v 5 is a section taken substantially on line 5-5 of Fig. 4.

Fig.. 6 is a front elevation of the roller platen `and the platen sliding crank; with parts `.broken away for clearer illustration.

Fig. 7 is a section substantially on line 7-7 of Fig. 6.

Fig. 8 is a perspective .view of an alternative form of roller platen with parts broken away.

Fig. 9 is a fragmentary perspective of the platen sliding crank and operating mechanism therefor.

Fig. l0 lis a perspective view of thetprinting die and the platen showing a workpiece (partially broken away) in position to be printed.

Fig. ll is a perspective of a workpiece with the printing thereon.

Referring to the drawing, the figures thereof illustrate a value printing machine according to `the present invention. The showing is in the form of a postage printer, although it will be appreciated that tax stamp printers and other value printing devices can be similarly constructed if desired. t

The printer in the particular form shown comprises a frame 13 including a base .15, a bearing casting 17 and side plates 19 and 21 mounted one ateither side of the casting 17. A postage indicia printing die 23 which also includes settablevalue printing wheels 25 and date printing wheels 27 (Fig. l0)l is mounted lat a suitablei location towards one end of the frame 13, and preferably in a downwardly facing position.

A main drive shaft 29 is rotatably mounted in suitable bearings on the casting 17 and is arranged to be actuated by theswinging of a manual lever (not shown) which drivingly engages the pin 31` at the end of the shaft, shown in Figs. `l and 5. Suitable connections (not shown) are provided for driving register wheels to add inthe amount set on the value printing wheels 25 in a knownmanner whenever the shaft 29` is rocked, through a full printing cycle of operation. t

The main drive shaft 29 also has control over the print-` ing movement of a platen 33 which is moved towards and pressed resiliently against the die 23 'whenever the shaft 29 is rocked to drive the register wheels. The mechanism for accomplishing such platen movement includes platen carrying arms 35 rigidly connected to the ends of rock shaft 37,` which, together with effort-receiving arms 39 rigidly connected thereto form a

bell crank

35, 37,` 39.

Resilient urging means for the bell crank is provided and includes the countershaft 41,.Figs. 4 and 5,`supp0rted by `suitable bearings in the casting 17 and drivingly connected to the main drive shaft 29 by gears 43, :45. Rockable` with the: countershaft 41 is a cam 47` whichtengages a follower roller 49 carried between a pair of arms 51..

Said arms 51 form with the roller a bail freely rockable on shaft 37. A rockable tie tmember 53, joining `the arms 51 adjacent their upper endspcarries a tension rod 55,` extending slidably through a rockable' tie and thrustreceiving member 57, carried by and between `the upper ends of effort-receiving arms 39. The tension rod 55 supports about its periphery a helical compression spring 59 which in effect presses against the thrust-receiving member` 57 at one end `and against an abutment 61 mounted at the free endof tension rod 55.l The abutment 61 is preferably threaded on the rod 55 for adjustability land may be locked in adjusted position by lock nut 63.` If` desired a bearing sleeve 65, having a head 67 for resting against the thrust-receiving member, may also be placed over the rod 55 and received within the spring 59 as seen in Fig. 4.

Thus, when the main drive shaft 29 is operated by a manual lever in the printing direction (anticlockwise in Fig. 4) the countershaft 41 will be rocked clockwise through gears 43, 45.; Cam 47 will then rock

bail

49, 51, 51 to the right in Fig. 4 which pulls rod 55 to the right and, through spring 59, moves

arms

39, 39 of the bell crank to the right, thus raising the ends of arms 35 and moving the platen 33 towards the printing die 23. The spring `59 is preferably relatively stit so that` arms 51and 39 normally move substantially in unison, over the greater portion of the stroke, the spring only being present to apply iinal printing pressure and `to allow relative movement in case of variation of workpiece thickness so that a full stroke of the operating handleland' main drive shaft 29 will be permitted in all cases regardless of such thickness and without crushing the workpiece, defacing the surface of the printing die 23 or placing excessive strain on any of the working parts, while also assuring proper printing Contact.

Platen structure As seen in the drawing, especially Figs. l, `3, 6 and 7, the platen is made up of a track element or tray 69 which is supported for slight rocking movement between the endsof arms 35 by means of

pintles

71, 73, and which has

elongate guide slots

75 and 75 in its bottom wall. At each side of the` tray and integrally connected thereto are rails 77 provided withlaterally extending flanges 79 for a purpose which will appear hereinafter. Slidable back and forth within the tray 69 is a carrier 81, shorter than the tray 69 and provided with laterally `extending supporting rollers 83 engageable with rails 77 to provide for free reciprocation of the carrier within the tray. The carrier 81 is channel shaped and has side walls i 85 provided with vertically elongate slots 87 as seen especially in Figs. 6 and 7. Associated with each slot s a roller 89 supported rotatably on a shaft 91 whose ends ride in a pair of the slots 87.` Each of the rollersis preferably covered with a resilient material, e. g. rubber, and is also resiliently supported. This support consists in` a bail 93 associated with each roller, pivoted at its ends on the roller shaft 91 and providing a downwardly facing channel formed by flanges 95. A free leaf spring 97 is situated beneath each bail 93 and is positioned by the flanges 95 so as always to urge the bail upwardly and with it the shaft 91 `and the corresponding roller 89.l The upper ends of slots 87'limit the upward travel of the rollers under the influence of the springs, and the walls of the Slots confine the roller movement to an up-and-down reciprocation, preventing lateral displacement thereof.` Any suitable means, for example, the snap rings 99, shown in Fig. 7, may be used to keep the shafts 91 centered in their respective rollers.

Fig. 8 illustrates an alternative form of platen 33a using a different roller mounting which may be and preferably is substituted for that shown in Figs. 6 and 7. Here the carrier 81a has side walls 85a each provided with only three openings instead of having a slot 87 at cach roller as in the previously described form. Passing through and snugly fitting within each opposed pair of such openings is a shaft 101 whichhas at its ends, exteriorly of the carrier, supporting rollers 83a riding on rails 77 of the track element 69.` Loosely mounted on cach shaft 101 is` a r0llersupport 93a having side walls 94 in which are rotatably supported a pair of rollers 89. Each support 93a also has depending end flanges 95a Whichposition the ends of a leaf spring 97a for urging the support 93a upwardly with respect to the shafts 101. As seen in Fig. 8, 4the mounting of the roller supports on the shafts 101 is accomplished by slots 103 which provide for vertical movement but prevent against lateral displacement. In this form, no additional retaining means will be required for roller shafts 91a since these can merely be of a length to abut the inner surface of the walls 85a of carrier 81a.

From the foregoing description it can be seen that each roller, in either form of the invention, is in effect individually spring mounted so that if the workpiece carries in thickness a thick portion under one roller will not rob adjacent rollersv of their printing pressure.

In either form of the roller supporting mechanism, carrier 81 or 81a\is provided with downwardly extending lugs 105 .which slide' in guide slots 75 of the tray, and a driving lug 107 which slides in the slot 75 and projects below the lower surface of the tray 69.

Platen shifting Carried on the bottom of the tray 69 is a bracket 109 on which is pivotally mounted the bell crank 111 having on one enda fork 113 which receives the lug 107. The other end ofthe bell crank has an operating head 115 which is received in the notch 117 of a platen shifting bar 119 (see Figs. 3 and 9). As seen especially in Figs. 2 and`4, the platen shifting bar 119 is linked to but slidable on the pintle 73 by reason of the slot 121 formed in its end. The other end of the bar has an openmouthed slot 123 which receives the end of rock shaft 37 for sliding support thereon. A projection 125 on the shaft carried end of bar 119 is positioned to cooperate with one or the other of operating

arms

127 and 129 fixed to the main drive shaft 29.

It will be seen therefore, that when the main drive shaft is turned to print, i. e. anticlockwise in Fig. 4, the arm 127 will travel idly through about 90 degrees before it strikes the projection 125. During this travel the platen 33 is raised by arms 35 to move the workpiece into printing contact with the die 23, the shifting bar 119 merely following along to the dotted position indicated by numeral 119. For the remaining angle of rotation of drive shaft 29 (about 25 the cam 47 merely increases the spring pressure of spring 59 urging the platen against the die without significantly raising the arms 35 any further, while arm 127 simultaneously strikes the projection 125 and through it moves the shifting bar 119 into the dot-dash line position as indicated by numeral 119" in Fig. 4. Due to this shifting movement the operating head 115 of bell crank 111, through its engagement with the notch 117, is rocked and causes the fork 113 to slide the carrier 81 to the other end of the tray 69, thus passing the rollers 89 across the printing face of the die 23 on the back of thev intervening workpiece while in pressure contact therewith. The number of rollers 89 is such that their spacing will be about equal to the stroke of the carrier 81 or a little less, and enough are provided to insure that pressure will be applied over the entire face of the die at one time or another.

During t-he return stroke of the operating handle, which corresponds with clockwise rotation of main drive shaft 29, the first increment of movement, about 25 degrees, merely releases the spring pressure of spring 59 against the workpiece. Arm 127 moves away from the projection 125 and arm 129 has not yet made contact with it. Thus the platen 33 remains in light contact with the workpiece, but with the rollers 89 immobile. Retraction of the carriage 81 with rollers 89 to home position actually occurs in response to lowering of the platen arms, for when the pressure of spring 59 is removed and the weight of the platen parts starts to cause lowering of the platen, one arm of the bell crank 111 will strike against the edge of a return cam 131 and will be moved thereby progressively towards its home position as the platen position becomeslower. As the bell crank 111 is returned to home position, the carrier 81 and shifting bar 119 are returning with it to the position of Fig. 2 and the solid line position of Fig. 4 respectively, due to their direct mechanical connection with the bell crank 111. To guard against the possibility that gravity might fail to cause a complete return of the rollers to home position, i. e., to a position of readiness for another printing operation, the arm 129 is so positioned on the main drive shaft'29 as to contact the projection 125 and move the bar 119 and carriage 81 into full home position` in the event they have not already reached the same at the end of the return stroke. From the immediately foregoing description of operation it can be seen that printing pressure is necessarily removed from the rollers 89 before their return to home position is started so that danger of a double or blurred impression due to a reprinting is obviated.

Workpiec'e guiding and gripping To the end that the workpiece to be printed may be readily guided into the proper position above the platen rollers, a guide table 133 is associated with the platen 33. As best seen in Figs. 1 and 3 the guide table has a central opening 135 which accommodates `and surrounds the rollers 89 of the platen 33, and is resiliently mounted on the flanges 79 attached to track members 77. This mounting is effected in part by a plurality of sheet metal hooks 137 which are secured to the undersurface of the guide table 133 and intert with suitable notches 139 in the flanges 79. The hooks are affixed to the under side of the table 133 each by means of a screw 141 and a nut 143. The screws are threaded only adjacent the heads and have a smooth end for a guiding t in openings 147 of flanges 79. A spring 149 surrounds each screw 141 between the nut 143 and the flange 79 to urge the table-to the uppermost position as determined by hooks 137. Thus there is presented asubstantially smooth receiving surface normally about flush with the upper tangent to t-he roller surface, but which is capable of some relative movement in case of variation in workpiece thickness at different points so as net to interfere with the exerting of full roller pressure during printmg. v

Substantially overlying the guide table 133 is a shroud 151 which serves in part as an inverted upper guide table.

, In home position the shroud 151 depends a substantial distance below the surface of the printing die 23 as seen` in Figs. 1 and 2 andforms with the table 133 a guide chute into which a workpiece may be conducted without danger of smudging the same on the surface of the printing die and without conflicting with the edge of the platen 33. The shroud 151 is supported for vertical reciprocating movement by means of four parallel links 153, eachv pivoted at one end on a stud extending from the frame 13, and at the other to the shroud. Studs 155 and 157' are integral with side plate 19 and studs 159 and 161 are integral with side plate 21. Means is also provided for determining the lower limit of movement of the shroud and for preventing lifting of the shroud until the printing stroke has been commenced. As seen in Figs. i and 2, this means includes a pair of

slides

163 and 165, one on` each side of the frame 13. The slide 163 is mounted for sliding movement on stud 155 and another stud 167 by virtue of slots 169 and 171 respectively. Slide 165 is slidable on studs 159 and 161 and another stud 173 received within slots 175, 177 and 179 respectively. Each of the slides has an irregularly shaped cam slot 181 including a narrow throat portion 182 which cooperates with a projection 133 on the adjacent portion of the shroud. As seen in Figs..l and 2 the throat portions 182 of the slots 181 are so configured as to prevent raising ofthe projections 183 and hence of the shroud 151 when the parts are in home position, whereby the shroudalso performs the function of assisting in preventing the taking of unauthorized impressions from the value printing die 23.

AThe slides 163 and 165 are each provided with rack` teeth k185' which mesh with gear segments 187 on opposite ends of the main drive shaft 29. Thus whenever the' The slides prefer- 7 ably `do not contribute movement tothe shroud 151 but merely govern its movement. In the preferred form shown, the shroud is actually raised when a workpiece on the table 133 comes into contact with itsunder 4surface and lifts it, the workpiece then being gripped` to some extent between the table 133 and the shroud 151 to hold it in proper position. By the time raising movement of the shroud by the tabler 133 is ready to commence, the

slides

163 and 165 have progressed forwardly under the influence of segments 187, a distancesutiicient to put the projections 183 clear of the narrow throat portions 182 of the slots181 and in a` position where raising of the shroud 151 lby the table 133 or the workpiece thereonis permitted. drive shaft are returned to home position, the narrow throat portion of the slot 181 returns to the Figs. l and 2 position, again locking the shroud 151 in lowered position.

Inkng the printing `die In the form of the invention shown in the drawing, Figs. l, 2 and 4,` there is provided an inking roller `189 carried at the free end of a linkage consisting of hingedly connected links 191 and 193, one end of llink 193 being integral with an inker drive shaft 195 which is rotatable on the frame 13 about an axis parallel with an ink `supply roller 197, also rotatable on the` frame 13.`

The links 191 and 193 are acted on by a suitable spring 199 arranged to urge the roller 189 towards the axis of shaft 195, so that it will be urged into contact with the die 23 or the ink `supply roller, whichever it is adjacent at the moment. One of the slides, namely the slide 165 shown in Figs. 2 and 4, carries rack sections 201 tand 203. The rack 201 has a short toothed portion 201:1 and a flat portion 2011; and meshes with a Geneva gear 205 which has a gear segment 205e and a flat stop portionl 205b, and which is drivingly connected lwith the inker drive shaft 195.` Rack section 203 meshes with a pinion 207 which is connected with the ink supply roller 197 to rotate the same.

Thus it can be seen that the ink roller 189,in\the home position, lies against the rear portion of the printing die 23, ready to roll forwardly across the `printing surface to ink the same. When the slide 165 is moved is response to movement of the main drive shaft 29, through the offices of segment 187, it will first rotate the inker shaft 195 through a small angle, about 70 degrees due to the action of the meshing toothed portions 201a and 205a, and will then slide without further rotating the inker shaft whentheflats 201b and 20511` come into contact. The rotation of the shaft 195 causes inking roller 189 to roll across the surface of `die 23, inking the same, and up into contact with the rotating `ink supply roll197 where it remains for the rest of the printing stroke, this position being illustrated in dot-dash lines in Fig. l.` On the return stroke, the inking roller 189 remains in `contact with the ink supply roll 197 until the toothed section 201a of the rack again meshes with the toothed section 205:1 of the Geneva gear, returning the parts to home position during the final portion of the slide stroke. Throughout the `stroke `of the slide 165, the ink supply roller` 197 is rotated continuously by rack `203 `through pinion 207,` except for .the `instant at which direction is reversed. From Figs. 1 and 2 it can be seen that the inker mechanism, especially `the roller 189 and link191, underlie the printing die 23 at all times when the equipment is not `in use. It therefore cooperates with the shroud 151 in preventing the` taking of fraudulent impressions from the `die surface, for by its direct geared connection with slide 165, `segment 187 and hence with main drive shaft 129, it is substantially irnpossible to displace the inker from its die-hiding position until the` main drive shaft is operated to simultaneously drive theregister in a known fashion.

If desired, in order to cause automatic return of the parts fully to home position aft'er a print is made, snit- When the operating handle and l able spring means (not shown) may be provided, such as a torsion spring on the main shaft 29, or a suitable tension spring between one of the

slides

163 or 165 land a xed point on the frame 13.

Fig. liillustrates the `relationship of `certain of the parts during printing. A workpiece Wsuch as gan envelope has been placed face up on the upper surface of the guide table 133 so that it underlies the printing die 23 and is ready for a postage impression to be made by rolling of the platen rollers 89 against the under surface of the workpiece.

Fig. l1 shows a workpiece after the printing of postage indicia 209 has been completed and the workpiece withdrawn from the machine.

In operation a workpiece such as W is inserted between the guide table133 and shroud 151 and shifted into the proper position for printing. Suitable guides or stops, heretofore known, may be provided for this purpose if desired, although, for purposes of clarity, these` have been omitted from the drawing. The printing is effected by operating a manual lever to rotate the main drive shaft 29 through about 115 degrees. This action first unlocks the shroud 151, causes the table 133 and platen 33 to come up against the shroud and grip the workpiece therebetween, retracts the inking roller from the face of the printing die 23 and into contact with the rotating ink supply roll, moves the workpiece and platen 33 upwardly into contact with the die with a yielding pressure (simultaneously raising the shroud), and finally shifting the platen 33 to roll the rollers 89 thereof forcibly along against the back of the workpiece to print all parts of the die. Upon the return stroke of the main drive shaft 29, the platen 33 is first allowed to drop away from pressure engagement with the workpiece and then s shifted back to home position on its carrier, the tab1e`133 lowers, permitting the shroud 151 to drop to its lowerrnost position where it is automatically relocked by the narrow throat portions 182 of slots 181 on slides163 and 165. In the meantime the inking roller 189 has been returned to home position underlying and obscuring the printing die 23 and lying in a position of readiness to ink the die surface for the next printing.

While the structure illustrated in the drawing is particularly adapted for postage printing, it will be understood that the invention is not thus limited, and that the printing of tax-paid indicia, and other value printing operations are embraced within the invention as indicated by the scope of the'subjoined claims.

What is` claimed is:

1. A printing machine comprising a fixed substantially coplanar printing die; a platen including a slidable carriage having a plurality of rollers mounted therein on yieldable axes and normally spaced from said die for receiving a workpiece therebetween; an operating member; an arm rockable about a fixed axis in response to movement of said operating member movable in one direction for printing; a lever rockable aboutsaid axisand having one leg adjacent said arm and the other connected to said platen; and a resilient connection between said arm and the adjacent leg for normally rocking said lever in concert with said arm, and for applying printing pressure between said die, said platen and an intervening workpiece when they are in contact; and means actuated in response to the movement of said operating member in printing direction for sliding said carriage and thereby rolling said rollers across the backof the workpiece while the die, platen and workpiece are in pressure con tact.

2. A printing machine comprising a fixed substantially coplanar printing die; a platen including a slidable carriage having a plurality of rollers mounted therein on yieldable axes and normally spaced from said die for receiving a workpiece therebetween; an operating member; an arm rockable about a xed axis in response to movement of said operating member movable in one direction for printing and movable in the opposite direction for returning to nonprinting position; a lever rockable about said axis and having one leg adjacent said arm and the other connected to said platen; and a resilient connection between said arm and the adjacent leg for normally rocking said lever in concert with said arm, and for applying printing pressure between said die, said platen and an intervening workpiece when they are in contact; and means actuated in response to the movement of said operating member in printing direction for sliding said carriage and thereby rolling said rollers across the back of the workpiece while the die, platen and workpiece are in pressure contact, said connection and means being responsive to the movement of the operating member in the opposite direction for tirst releasing the printing pressure between said die, said platen and an intervening workpiece, and then sliding said carriage to initial position.

References Cited in the le of this patent UNITED STATES PATENTS Bowlus Oct. 29, Putnam Dec. 19, Dugdale Apr. 21, Howard Oct. 27, Ford June 12, Ward June 9, Wheeler Jan. 19, Moore Jan. 24, Elder Oct. 28, Rast Sept. 27, Rouan Nov. 15, Hanson et al. Sept. 18, Elliott May 26, Aurbach Oct. 5, Lasseter Aug. 16,