US1370071A - Intaglio-printing machine - Google Patents

Description

= I. TORNBERG. mmauo PRINTING MACHINE.

APPLICATION FILED MAR. 15, 1917- Mar. 1

3- SHEETS-S I ENTOR l. TORNBERG; INTAGLIO PRINTING MACHlNE.

APPLICATION FILED MAR.15|19H- Patented Mar. 1,1921.

3 SHEETS-SHEET INVENTOR.

fizz/M UNITED STATES PATENT OFFICE.

ISIDOR TORN'BERG, OF NEW YORK, N. Y., ASSIGNOIt TO B. HOE AND 00., OF NEW YORK,

. N. Y., A CORPORATION OF NEW YORK.

INTAGLIO-I PRINTING MACHINE.

Specification of Letters Patent. Patented Mar. 1, 1921.

Application filed March 15, 1917. Serial No. 154,912.

T 0 all whom it may concern Be it known that I, ISIDOR- ToRNBnRe, a citizen of the United States, residing at New York city, county of Kings, and State of New York, have invented certain new and useful Improvements in Intaglio-Printing Machines, fully described and represented in the following specification and the accompanying drawings, forming a part of the same.

This invention relates to improvements in intaglio printing machines, particularly that class of machines intended to printand perfect a web, and has for its object generally certain improvements in the construction and arrangement of the mechanism of such machines to effect better printing and more positive and convenient adjustment of the parts.

One particular object of the invention is to rovide an improved arrangement for drying the web after impression or impressions and before delivery from the printing mechanism of the machine.

The invention has for another object an improved construction whereby the engraved copper cylinders and their cooperating impression cylinders or rolls may be moved out of printing relation for the purpose of conveniently removing the engraved cylinders from the machine, or, if it should be for any reason desirable, for briefly stopping the printing relation, and the parts moved back into the position they occupied before being movedautomatically so as to dispense with manual adjustment, an important advantage, especially in perfecting machines. I

The invention has for a furtherobject an improved construction for alining the engraved printing cylinders where two couples, each including such a cylinder, are used to perfect the web.

The invention has for another object an improved construction. for supporting and operating the doctor or scraping blade employed in intaglio machines for removing the surplus ink from the engraved form' cylinders. j The invention has for a still further obect, where awide web is to be printed on,

an improved construction of impression cylinder or roll, whereby any deflection or sag in the roll due to its length is compensated for and an even impression is obtained throughout the roll.

\Vith these and other objects not specifically referred to in view, the invention consists in certain novel parts a'ndcombinations as hereinafter specifically described in connection with the accompanying drawings, in which Figure 1 is a side elevation, with certain parts broken away, of an intaglio printing machine, illustrating the various features of the invention, the particular machine shown being a perfecting machine;

Fig. 2 is a side elevation, on an enlarged scale, of a printing couple such as is illustrated in Fig. 1, the printing cylinder and the impression cylinder being illustrated as oil impression, certain parts being shown in section;

Fig. 3 is an end view, partly in section and partly broken away, of part of the construction shown in Fig. 2, the figure showin one side of the machine;

Fig. 4 is a detail sectional view on the line 4-4 of Fig. 3, illustrating certain driving connections;

Fig. 5 is a partial plan View, certain parts being broken away, illustrating the improved construction for vibrating the doctor roll;

Fig. 6 is a cross-sectional view taken .on line'6-6 of Fig. 5, illustrating the adjustment ,of the doctor blade vibrating mecha nism and certain driving connections; I

Fig. 7 is a cross-sectional view of an improved impression cylinder or roll intended particularly for use when printing on a wide web Figsp8 and 9 are side and front views, respectively, of an improved construction for causingthe impression roll or cylinder to have even impression throughout its.

length, Where the Web has a central margin,

and

Figs. 10 and ll are, respectively, side and g 'inafter described in detail.

Referring now to the drawings, the machine chosen to illustrate a concrete embodiment of the invention is an intaglio rotary perfecting machine, that is, a machine in which the web is printed and perfected -from engraved printing plates, though it will be understood that as to certain of the features the-invention is designed for and-may be used with intaglio machines of other types, such as machines for printing on butone side of a web or sheet and employing but one printing couple.

In the partlcular machine illustrated, the

web W is taken from one orthe other of two web rolls 1, 2 suitably mounted in the frame of the machine and suitably supported preferably as shown between the two printing couples indicated generally by the numerals 3, 4. The web is led over a tension roller 5 and guide rolls 6, 7 and 8 to the printing couple 4. In the best constructions, the web will be cleaned or dusted .prior to its being printed upon. While any suitable means for effecting this may be employed, in the machine shown there are provided two revolving brushes diagrammatically indicated at 9, 10, disposed so as to act on opposite sides. of the web.

, In the machine illustrated, the two printing couples shown each include a printing member which carries the matter to be printed, this printing member being, in the construction shown, a copper cylinder on which the matter to be printed is engraved, and this copper cylinder has cooperating therewith an impression member which in the present instance is a rubber-coated roll. Referring to couple 4', the cylinder -is marked 11 and the impression roll is marked 12, and this latter is held in printing relation with the copper cylinder through a spring-controlled socket 13,here- After being printed on one side by the printing couple 4, the web is printed upon on 'its other side and perfected by printing couple 3, which,

in the machine illustrated, is identical with the printing couple 4, including a copper engraved form cylinder 14 and cooperating impression cylinder or roll 15 supported in spring-controlled contact with the engraved cylinder. by means of a spring and socket construction similar to that marked 13 before referred to.

Machines constructed in accordance with i the invention will include means for drying the web'a'fter it has had its first, im-

pression and, where the machine is a per- .fecting machine, there will also be. included means for drying the web after its perfecting impression and before its delivery to the particular delivery mechanism employed. This drying mechanism may, of course, vary widely in its character. In

the drawings is illustrated a mechanism for effecting the dryingin two different ways, which have been found very efficient. In the preferred construction, the web, after its first impression, is led through a drying casing or chamber 17 oversuitable guide width of the paper at high velocity, so that no moisture is allowed to accumulate in the casing or chamber 17, these nozzles being distributed along the web path in suitable numbers, and delivering air oppositely to the run of the web, the nozzles effecting a good control and distribution of the air. Afterthe web has been perfected by the couple 3, it is again returned to the casing 17 over suitable guide rolls 20 and the other side of the paper dried in a similar man'- ner by the highly heated swift moving air, the web being delivered from the casing by drawing rollers 21 to any suitable delivery mechanism. If desired, the air may be suppliedthrougha pipe 19 and exhaust vfrom the casing or chamber 17 through a suitable pipe 22, or, if desired, the air may be supplied both from the nozzles and either the pipes 19', 22, exhausting through the 'opposlte one.

ployed which will deliver a blast of air inthe opposite direction to the run of. the

web. .This air may be supplied in any suitable manner from the series of nozzles 24 before referred to. After the web is perfected, it is led over a second row or bank of steam heated rollers 25 with which, in

the preferred construction. also cooperate the nozzles 24 to supply the air from the nozzles in a direction contra to that 'oftherun of the web. a

With either of these constructions, the web is thoroughly dried after its first impression and after it has been perfected and before final delivery, and smutting of the freshly printed surfaces avoided:

Machines constructed in accordance with the invention will be provided with means 1 0 whereby the printing relation between the impression cylinders or rolls and the cooperating engraved co per cylinders may be broken so as to stop t e printing operation and so that where it is necessary the en graved copper cylinders may be readily removed from the machine for the depositing of new copper thereon or producing new printing matter. lVhile this may be done by moving either the impression rolls or the copper cylinders away from each other, in the particular construction illustrated, where the cylinders of the couples are vertically arranged the means preferably employed will effect the lowering of the copper cylinders away from the impression cylinders or rolls, and the means will furthermore be such that the cylinders will be simultaneously raised or lowered. The particular construction for effecting this may be somewhat varied, but will be the same for eachprinting couple where, as in the present instance, two printing couples are employed, and the same letters of reference will, for convenience, be applied to like parts in each printing couple, but it will be understood that this raising and lowering mechanism may be employed in machines employing but a single couple. As shown, referring particularly to Figs. 2, 3 and 4, which illustrate one end of the printing couple 4, the printing cylinder 11 before referred to is journaled at each end in a journal box 27 which is vertically movable in guides 28 formed in the frame 29 of the machine. These journal boxes are supported and given a vertical up and down move ment by means of operating screw rods 30,

7 one of which is shown in the drawings, having threaded ends 31 tapped into threaded nuts 32 secured in sockets in the lower end of the bearing boxes 27 before referred to. These rods (see Fig. 2) are provided with worm gears 33 by therotatio-n of which the operating rods 30 are rotated in either direction and the boxes 27 raised or lowered as desired.

Various expedients may be employed for causing rotation of the operating rods. In the best constructions, where two printing couples are employed, the means will be such that the operating rods will .be ro' tated simultaneously so as to cause the simultaneous raisin or lowering of the engraved copper cy inders, this being particularly important where it is desired to quickly stop the printing operation of the mac ine; A convenient construction for effecting this is in the provision of a shaft 34 extending across the machine between the printing couples as shown, this shaft being mounted in suitable bearings 35 and being provided at each end with gears 36, these gears meshing with worm gears 37 on cross and c.

manner, as through a reversing motor indicated at 39 (Fig. 1), this reversing motor driving the shaftthrough a gear 40 on the motor shaft and a gear 40' on the shaft 34.

In constructions where,'as described, the copper cylinders and impression cylinders are moved or separatedfrom each other, it is desirable that after this movement has been made the cylinders may be returned to the exact positions they occupied before such separation took place without manual adjustment. Machines constructed in the best form, therefore, will include devices for effecting this, which may be of various characters. In the particular construction illustrated, there is provided a limit switch 41, diagrammatically illustrated, which is provided with three circuit breakers a, b

This limit switch is to insure delicate and accurate adjustment, and is located close to the motor 39 and operated from the shaft 34 which is driven from the motor 39 before referred to, the switch being operated from the shaft in any usual manner, as by being moved along the shaft through the agency of a screw thread 42 thereon. Of these breakers, one, as a, effects the shutting off of the current when the copper cylinder has reached its high position, as shown in Fig. 1; the second, as-b,

'when the copper cylinder has been moved ping of the printing operation, and the third, (1, effects a stopping of the motor when the boxes have been lowered to their full extent to permit the engraved cylinders to be taken out of the machine;

It will thus be seen that the printing relation between the engraved copper cylinders and the impression rolls may be broken for stopping the printing operation simultaneously for both the printing couples, and that the cylinders may be lowered sufficiently to permit'them to be taken from the machine so that when they are to be returned to position they can be returned to the exact position which they occupied prior to their lowering or removal; When the cylinders are to be taken out, the caps 43 of the journal boxes may be removed, a supporting bar, as 44 (see Figs. 2 and 3) placed beneath the cylinder shaft, and the 1 cylinder in any suitable manner, as by pro:

' turned the miter gear slides up and down on the rod and by its taking against the sides of the ope'ning 49 in the member 48,, causes a raising and lowering of the fountain to the same extent as the raising and lowering of the bearing block 27, and consequently, the cylinder. The means for independently adjusting the fountain rela tively to the engraved cylinders may be varied, but as shown the bracket 47 before re .ferred to has a depending part 50 in which is carried a hub 51 on a shaft 52 extending parallel with the fountain. This hub carlies a miter gear 53 which is in engagement Wlth'tllfl miter gear 46 before referred to. Onthe other end'of the hub is a gear 54 which is operated from a gear 55 on a short shaft which carries. a hand wheel 55, at one side of the machine. With-this construction, the fountain can be raised or lowered vertically-independently of the engraved cylinder and cylinder-operating means, and the fountain adjusted with respect to the cylinder as desired.

In intaglio machines employing an engraved cylinder as the printing surface, it is necessary to remove the surplus ink from the cylinder before the cylinder prints upon the paper. This is usually effected by a doctor blade which acts to remove by scraping this surplus ink, the ink-removed being returned to the fountain. It is desirable that the doctor blade be oscillated back and forth across the face of the cylinder, so that the parts may wear evenly. Where such oscillationtakes place, it is desirable that the dwell at the end of each oscillatory stroke of the blades be as brief as possible. Machines constructed in accordance with the invention, therefore, will provide means for oscillating the blade back and forth acrossthe face of the cylinder with asbrief stop as possible at the ends of the stroke. A pre ferred construction for effecting this is shown, and referring particularly to Figs. 5 and 6, there is provided a doctor blade 56 which extends across the face of the cylinder. This doctor blade is carried on arms 57, one of which is shown, pivoted on studs 58 secured on a carriage 59 which to effect adjustment of the blade pressure has a sliding movement toward and from the engraved cylinder, this being effected by means of the usual set screw construction 60. This carto oscillate the doctor blade, and thismovement is effected so as to give the least possible dwell at the end of each movement.

In the particular construction illustrated, and which has been found effective for the purpose, the carriage 59 is adapted to slide in ways 61 suitably supported in the frame of the machine and is oscillated by a rod 62 secured thereto at one end in any suitable manner, as by a hub 62' having a flange 62" taking into a recess in the carriage. This rod has at the other end outside the frame an eye 63 in which takes'a pin 64 carried on an ec'centric face 65 of a gear 66. Theface of the gear is slotted at 67 (see F ig. 6) so that the length of the stroke given the car- 66 is driven in any suitable manner. In the particular construction illustrated, it is.

-riage may be varied as desired. The gear 1 from the engraved cylinder. Where such construction is employed, however, to prevent the blade from coming into contact with the periphery of the cylinder at the same point, connections are provided whereby a varying number of revolutions of the cylinder will cause one complete oscillation of the blade. While this may be effectedin various ways, in the particular construction illustrated the shaft 69 is driven through a gear 70 on the shaft through an intermediate 71 and a gear 7 2 on the cylinder-shaft.

The number of teeth on the gears 70 and 72.are so proportioned that for successive complete oscillations of the blade a varying number of revolutions of the cylinder occurs, so that the blade meets successive polnts on the periphery of the cylinder and even wear of the cylinder-is effected.

' As before stated, the rubber impression rolls are held in contact with their cotiperatmg engraved cylinders under a desired'tension, the tension being determined by a spring. It is desirable that the pressure of the impression rolls on the cylinder may be slightly varied, without varying the position at which the roll is set to operate normally. While this may be effected in various ways, in the particular construction illustrated (see Figs. 2 and 3) the impression cylinder or roll 12, for instance, is supported in bearings 75 having extensions 76 seated in the sockets 13 fast on the frame 29 of the machine. These sockets are provided with heavy springs? 8 which take against the extension 76, before referred to, and adjustable collars 79 screwed into the interior of cylinders on the coppercylinders can be obtained Without altering the normal adjusted position of the rolls when this is required, and this can be done while the machine is operating.

In intaglio machines, it is frequently desirable to print on extra wide webs, for instance, double wide webs. When this width of web is to be printed upon, the .printing and impression cylinders have consequently to be very-long, and when such is the case provision should be made for obtaining an even impression over the entire width of the cooperating cylinders, because, on account of the lengths of the cylinders, particularly of the rubber impression cylinders, these impression cylinders are apt to be deflected or sag centrally. Various means may be employed for compensating for this deflection or sag, several such meansbeing illustrated in Figs. 7 to 11 of the drawings. Referring to Fig. 7 it has been found that this deflection is effectually compensated for by making the hard steel core of the impression cylinder or roll 12 of greater diameter centrally than at its ends, as indicated by the numeral 83 in r 1g. 7, the increase being approximately the amount which the roll will sag. This construction of roll allows for thedeflection which occurs when a wide roll is used and causes the rubber covering, which must be the same diameter from end to end of the roll to maintain a straight outer face across the roll and to exert the same pressure at its ends as at its central part.

If desired, the roll shown in Fig. 7, or a. roll with a core of equal diameter throughout its length may be used in combination with devices acting on the center of the roll to prevent jumping or excessive vibration at that point, which is apt to occur in long rolls driven athigh speed. Thesedevices may vary somewhat in structure, depending more or less on the character of the. web to be printed. Where a wide web with a center margin is to be printed, a construction. such as shown in Figs. 8 and 9 may be employed. In this construction, the rubber blanket is cut away, as indicated at 8-1 in Fig. 9. there is provided what in effect is a central bearing riding directly on the roll at. this point. This bearingmay take various forms, but as shown in Figs. 8 and 9 it consists of a bearnig block .85 in which are mounted three bearing rolls 86 disposed about the upper periphery of the impression cylinder. The bearing block 85 is or may be supported from a spring socket 87 suitably secured to the frame of the machine, the rolls in this construction running on the metal of the roll.

Where the web to be printed on has no central margin, the form of center bearing shown inFigs. 10 and 11 may be employed. In this construction, the bearing block 85 has mounted therein guide rolls 88, which rolls have passing over them a short endless belt 89 of suitable flexible material, this 'construction being adopted so that the rubber of the impression roll will not be cut or injured, the flexible belt running directly on the rubber of the roll. This construction results in a strong, rigid impression cylinder, in wlnch the impression is equal throughout the length of the cylinder and, in the case of long cylinders, jumping or undue vibration of the cylinder is avoided, an especially important feature at high speeds.

In perfecting rotary intaglio machines it may frequently become necessary or desirable to aline the two printing cylinders of the perfecting couples so that they will be brought into desired register, and it is also desirable to effect this while the machine is running. Rotary perfecting machines, therefore, constructed in accordance with the invention will include means for effecting this. Vhile the particular construction.

by which this is done may be somewhat varied, as illustrated (see particularly Figs. 2 and 3) the end of the shaft 90 of the engraved cylinder 11 is formed with a groove 91 in which takes one side of a two-part collar 92 pivoted to a stud 93 carried in a bracket 94 fast to the bearing block 27 hereinbefore referred to. The other side of this collar takes into the recessed end of an adjusting screw 95, which is or may be operated by a hand wheel 96, the operating screw 95 being preferably arranged in alinement with the axis of the'cylinder shaft 90. With this construction, the cylinder maybe moved endwise in either direction as desired. When the cylinder is to be removed, as hereinbefore described, the pivoted collar 92 is swung on its pivot away from the shaft I as to some of its. features the invention may ,be employed with intaglio machines other Ethan rotary perfecting machines.

- What is claimed is:

combination with an impression member and i an engraved form member, one of which is movable, rigid supports on which the movable member is mounted, gears on the supports by which they may be moved to separate the impression and form members with a straight line movement, power operating mechanism, gear connections from the power operating mechanism to the gears on the supports, and means for stopping'the movement of the gears when the movable member has been returned to its .initial position.

. 2. In an'intaglio printing machine, the combination with an impression cylinder, of an engraved form cylinder, rigid supports on which the form cylinder is mounted, gears on the supports by which the supports may be moved to separate the form cylinder from the impression cylinder with a straight line movement, power operating mechanism, gear connections between the power operating mechanism and the gears on the supports, and means for stopping the movement of the gears when the form cylinder has been returned to its initial position.

. 3. In an intaglio printing. machine, the combination with an impre'ssioi'i cylinder and the engraved form cylinder, of power driven means for separating the cylinders and for returning them to the position they occupied before the separation, and a moving switch operating to stop the cylinderseparating means when the cylinders have assumed their initial position.

4. In an intaglio printing machine, the combination with a plurality ofprinting couples each including an impression memher and an engraved form member, one of which is movable, rigid supports on which the movable members are mounted, gears on the supports by which they may be moved to separate the impression and form members with a straight line movement, power operating mechanism common to the couples, gear connections from the power operating mechanism to the gears on the supports for simultaneously operating said gears, and means folstopping the movement of the gears when the movable members have been returned to their initial position.

5. In an intaglio printing machine, the combination with a plurality of printing couples each including an impression cylinder and an engraved 'form cylinder, rigid supports on. which the form, cylinders are mounted, gears on the su ports by which the supports may be move to separate the the impression and form cylinderswith a straight line movement, power mechanism, gear connections from the power mechanism to the gears on the supports whereby all the supports may be operated simultaneously to separate the form cylinders from the impression cylinders, and means for stopplng the movement of the gears when the form cylinders have been returned'to their initial position.

6. In an intaglio printing machine, the combination with a printing couple including an impression cylinder and an engraved form cylinder, of a second printing couple including an impression cylinder and an engraved form cylinder, of power driven means for simultaneously moving the forni cylinders away from the impression cylinders, and a moving switch controlling the cylinder operatin means for simultaneously returning the cylinders to their initial positions.

7 In an intaglio printing machine, the

combination with a plurality of-printing couples, each including an impression cylinder and an engraved form cylinder, of means for moving the form cylinders to separate them from the impression cylinders, sliding bearings in which the form.

ders, sliding bearings in which the form cylinders are mounted, supporting rods operating to move the bearings, power operating means for the rods common to all, and a moving switch for'causing the rod operating means to stop when the cylinders have reached their initial positions.

9. In an intaglio printing machine, the combination with a plurality of printing couples, each including an impression cylinder ,and an engraved form cylinder, of means for moving the form cylinders to, separate them from the impression cylinders, sliding bearings-in which the cylinders are mounted, supporting-rods for moving the bearings, a shaft common to all the rods for operating them, power operating means for the shaft and a movable switch operated from the shaft for stopping the rotation thereof. a

10. In an intaglio printing machine, the combination with a rinting couple including an impression cy inder and an engraved of which causes the operating means to separate the cylinders slightly to stop the printing operation and the further movement of which causes a further separation of the cylinders to permit the removal of one of them, the controller also acting on its return movement to cause the mechanism to return the cylinders to and stop them at the position they occupied before the separation.

11. In an intaglio printing machine, the combination with a plurality of printing couples, each including an impression cylinder and an engraved form cylinder, shafts therefor, adjusting screws in alinement with the shafts, pivoted adjusting'collars taking on the shafts and on the screws for adjusting the shafts endwise, and means for operating the screws.

12. In an intaglio printing machine, the combination with a plurality of printing couples, ,each including an impression cylinder and an engraved form cylinder, shafts therefor, movable bearings in which the shafts are mounted, adjusting screws in alinement with the shafts carried by the bearings, pivoted collars taking on the screws and on the shafts also carried by the bearings, and means for operating the screws.

13. In an intaglio printing machine, the combination with an impression cylinder and a form cylinder, of means for separating the cylinders and for returning them to the position they occupy before separation, a power shaft, and a controller movable by the shaft to different positions to cause the cylinders tobe separated to varying degrees by the separating means.

14. In an intaglio printing machine, the combination -with an impression cylinder and a form cylinder, of means for separating the cylinders and for returning them to the position they occupy before separation, a power shaft, and a switch moved by the shaft to different positions to cause the c linders to be separated to varying degrees y the separating means.

15. In an intagliov printing machine, the combination-with a plurality of printing couples, each including an impression cylinder and a form cylinder, power driven means for separating the cylinders and for returning them to the position they occupy before separation, a common power shaft for the couples and a controller operated from the shaft to different positions to cause the cylinders to be separated to varying-degrees by the separating means.

16. In an intaglio printing machine, the combination with an engraved .form cylinder and a cooperating impression cylinder, of a doctor blade for removing surplus ink from the form cylinder, a gear on the form cylinder, and a gear operatively connected to the blade for oscillating the same, the

teeth of the gears being so proportioned that the blade is caused to bear against a different part of the form cylinder at each complete oscillating movement,

17. In an intaglio printing machine, the combination with an engraved form cylinder and a cooperating impression cylinder, of a doctor blade for removing surplus ink from the form cylinder, a gear on the form cylinder, an'eccentric pin operatively con- .nected to the blade for oscillating the same,

of a doctor blade for removing surplus mkfrom the form cylinder, a gear on the form cylinder, an eccentric pin operatively connected to the blade for oscillating the same, means for adjusting the pin for varying the .oscillating movement, and a gear for operating the eccentric, the teeth of the gears being so proportioned that the blade is caused to bear against a different part of the form cylinder at each complete oscillating movement.

19. In an intaglio printing machine, the

combination with animpression cylinder and a 'co6perating engraved form member,

of bearings for the cylinder, springs 00- operatingwith the bearings, means for adustlng the springs for normal prlnting pressure, and further means for adjusting the same springs to vary the pressure without changing the normal adjusting means.

20. In an intaglio printing machine, the combination with an engraved form member, of an impression cylinder having a hard core and rubber cover, the cylinder being so formed as to provide in itself means for compensating for central deflection.

21. In an intaglio printing machine, the combination with an engraved form member, of an impression cylinder having a hard core and a rubber cover, the core decreasing in diameter from its center g'radually toward its ends.

22. In an intaglio printing machine, the combination with an engraved form'member, of an impression cylinder having a hard core and a rubber covering, and a plurality of short bearing rolls riding on the cylinder at or near the center only. I v

23. In an intaglio printing machine, the combination with an engraved form member, of an impression cylinder having a hard core, a rubber covering about the core, and a flexible bearing member riding on the cylinder centrally thereof.

24. In an intaglio printing machine, the combination with an engraved form mem- 'ber, of an impression cylinder having a hard core formed with a central diameter greater core, a rubber covering, a belt and guides than that at its end, a rubber covering for for the belt, the belt bearing on the cylinder the core, and a central bearing riding on 10 substantially centrally. the cylinder.

25. In an intaglio printing machine the In testimony whereof, I have hereunto set combination with an engraved form memmy hand.

ber, of an impression cylinder having a hard ISIDOR TORNBERG.

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