US2845860A

US2845860A - Two-color offset printing press

Info

Publication number: US2845860A
Application number: US429211A
Authority: US
Inventors: Mestre Luis
Original assignee: LEWFOR DEV CORP
Current assignee: LEWFOR DEV CORP; LEWFOR DEVELOPMENT Corp
Priority date: 1954-05-12
Filing date: 1954-05-12
Publication date: 1958-08-05
Anticipated expiration: 1975-08-05

Description

Aug. 5, 1958 1.. MESTRE TWO-COLOR OFFSET PRINTING PRESS 4 Sheets-Sheet 1 Filed May 12, 1954 Aug. 5, 1958 MESTRE TWO-COLOR OFFSET PRINTING PRESS 4 Sheets-Sheet 2 Filed May 12/ 1954 IPHI |y y r INVENTOR LUIS MESTRE,

ms ATTORNEY.

Aug. 5, 1958 L. QMESTRE TWO-COLOR OFFSET PRINTING PRESS FiledMay 12, 1954 4 Sheets-Sheet 3 INVENTOR.

LUIS MESTRE.

HIS ATTORNEY.

1958 L. MESTRE 2,845,860

TWO-COLOR OFFSET PRINTING PRESS I Filed May 12, 1954 4 Sheets-Sheet 4 II II II II III II II II I l I I (I II II II III l l I l I! I'IIII Illu INVENTOR- LUIS MESTRE.

HIS ATTQRNEY.

United States Patent TWO-COLOR OFFSET PRINTING PRESS Luis Mestre, New York, N. Y., assignor to Lewfor Development Corporation, New York, N. Y., a corpora tion of New York Application May 12, 1954, Serial No. 429,211

11 Claims. (Cl. 101-177) The present invention relates to offset printing presses and its principal object is to provide a novel and advantageous offset printing press to'print two colors simultaneously from the same blanket cylinder. Another object of the invention is to provide a twocolor offset printing machine comprising an impression cylinder, a blanket cylinder, two plate cylinders and means for separating the blanket cylinder from the impression cylinder and said plate cylinders.

Another object of the invention is to provide a twocolor offset printing press comprising an impression cylincolor press.

Other objects, features and advantages will appear upon consideration of the following detailed description and of the drawings in which: v

Fig. 1 is a fragmentary side elevation of a press embodying the present invention;

Fig. la is a side elevation of the upper part of the press which was omitted from Fig. 1;

Fig. 2 is a side elevation similar to Fig. 1 but omitting certain parts and showing others in position to print two colors;

Fig. 3 is a fragmentary top plan view of the machine I illustrated in Figs. 1 and In;

Fig. 4 is a sectional view illustrating the cam structure utilized in shifting the blanket cylinder into and out of efiective relation with one plate cylinder and the impression cylinder and cam means adapted to shift the second plate cylinder from the blanket cylinder;

Fig. 5 is a fragmentary sectional view taken along the line 55 of Fig. 4; and

' Fig. 6 is a sectional view showing the mounting means for the shafts carrying the plate cylinders.

Referring to the drawings, the main frame of the twocolor machine of the present invention comprises front and rear frame members or plates 20 and 21 (Fig. 3) connected together in the same general manner as the front and rear plates of the one-color machine disclosed and claimed in said prior co-pending application Ser. No. 378,035, filed September 2, 1953.

In operation sheets of paper are fed one by one by means which may be substantially the same as disclosed in said prior application, to an impression cylinder 22 where each sheet may be gripped and carried between said impression cylinder and a blanket cylinder 23 and transferred to a rotary discharge device 24 as in said prior application, the two diflierent inks being applied to said blanket cylinder 23 by two

plate cylinders

25 and 25a.

During a printing operation the blanket cylinder 23 is substantially in contact with the impression cylinder 22 and the

plate cylinders

25 and 25a. During the actual printing operation the blanket cylinder is separated from the impression cylinder by sheets on which ink from the blanket cylinder 23 is applied. As in the one-color press of said prior application, absence of a sheet of paper will cause the blanket cylinder of the two-color press to be separated from the impression cylinder and the plate cylinders. In the press of the prior application;

separation from the impression cylinder and the single plate cylinder may be effected merely by movement of the blanket cylinderaway from theimpression cylinder and the plate cylinder.

However, in the two color machine of the presentinvention transverse movement of the blanket cylinder may effect separation between the blanket cylinder and. the impression cylinder and one of the plate cylinders. Separation from the other plate cylinder must be effected in another way. According to the machine of the present invention plate cylinder 25 is mounted in the ends 26 and 27 of an auxiliary frame pivotally mounted on pivots 28 in brackets 29 fixed on the plates,20 and 21 near the lower edges thereof and the movement of the auxiliary frame may be elfected by means of links 30, each con,- nected at one end by a pivot 31 to a plate of the auxiliary frame and at the other end mounted on an eccentricv 32 carried on a shaft 33 about which blanket cylinder ,23.

revolves. Said shaft 33 has fixed thereon eccentrics 34 which fitin bearings in the sides 20 and 2101? the main, frame so that when the shaft is turned the blanket cylinder. may be moved away from the impression cylinder and the other plate cylinder 25a. The position-controlling links 30 for the auxiliary frame act to move the auxiliary frame away from the main frame as the blanket cylinder, 23 is withdrawn so as to prevent ink from the plate cylinder 25 from being applied to the blanket cylinder 23.

Water is applied to the plate cylinder 25 from a usual I water fountain 'or trough 35 in which is mounted a water roller 36 carried on a shaft 37 extending through the.

opposite ends of the trough and having at one end a r ratchet wheel 40 operable counterclockwise by a pawl 41 on a pawl carrier 42. Water from the water roller is transferred through a series of rollers to a molleton roller 43 which normally is in contact with the plate cylinder 25 and supplies water thereto. This water supplying unit is substantially the same as plication.

Said auxiliary frame also carries an inking unit comprising an ink fountain or trough 50 in which there is an ink roller 51 on a shaft 52 which passes through the ends of the trough. Mounted on shaft 52 of the inkingroller is a ratchet wheel 53 which is rotated in a clockwise direction by a pawl 53a on a pawl carrier 54 mounted to swing about the shaft of the ink roller 51. Ink from. the ink roller is transmitted by means of a series of rollers such I as disclosed in said prior co-pending application, to form rollers 55 which normally contact with the plate cylinder: 25. Said form rollers are mounted in pivoted arms 56 which are, as in said prior application, normally urged toward each other by springs connected to a fixed mem-v ber at their inner ends and at their Said rocking lever 62 is mounted on said pivot 63 be in said prior co-pending ap-,

out-er ends to arms 57 pivoted on the arms 56 and yieldably holding in said arms .tween its ends and is actuated by means of a link 64 connected at one end to a pivot 65 on the lower arm of said lever 62 and at its other end to a rotary disk 66 by meansofa. pivot 67 mounted eccentrically on the disk. Said disk 66 is mounted on a transverse cam shaft 67:: extending from front to rear of the machine. On said shaft 67a is fixed a cam 68 with a short high part or dwell anda long low part or dwell.

Once each rotation, said cam 68 strikes a follower on a lever 70 pivoted on a shaft 71. Said lever 70 has an upperarm 72 provided at its upper end with a pawl 73 mounted on a pivot 74 at the upper end of'said arm72. Said; pawl 73has at. its forward end a downwardly extending. tooth 75 which duringa rearward movement of said arm 72 rides up on a pin 76. Projecting laterally from vthe pawl 73 is-a pin 77 extending through a slot 78. of a link 79pivoted at its rear end 80. Said link 79 is connected at its forward end by an upwardly extending link 81 toa bent lever 82 fixed at the end of its rearward extension on a shaft 83 mounted on a stationary frame. Said shaft 83 carries feelers such as disclosed in said prior co-pending application and if sheets of paper are being fed'through the machine the feeler fingers 83a are merely lifted from the paper and then dropped again on the paper.

'Ifthe feeler fingers. are thus held against dropping too far, the bent lever through the connecting link 82 and link 79 .holds the pawl in raised position, then in the forward movement of the pawl 73 it rides over an upward projection 84 on the upper end of a lever 83 mounted on a fixed pivot 86. On the other hand if there is no sheet of paper present when the feeler fingers drop, the pawl 75 will engage said upward projection 84 and will rock said lever 85 inxa counterclockwise direction. In this movement the lever '85 through a link. 87 rocks a block 88 in a clockwise direction and through a link 89 and spring connection acts to exert upward pressure on a link 90. The block 88 is pivoted on a pin 91 on which is also pivoted an actuator 92 extending downwardly and having at its lower endlan arm 93 which is connected by a pivot 94 with the rear end of said link 90. Mounted on a pivot 95 in the lower end of said actuator 92 is a lever 96 having. at its forward end a roller 97 pivoted thereon and engaging the lower edge of said arm 93. At its rear end said lever 96 is provided with a follower 98 in the form of a roller. Said follower 98 engages a cam 99 on said shaft 67 which cam has a short low dwell portion and a long high dwell portion. During the rotation of the cam 99, the same raises the follower 98 in its high portion and forces the actuator 92 to the left (Fig. 2) and advanc'es said link 90.

The. second advance movement of link 90 (Fig. 1) during absence of a sheet of paper beneath the feeler fingers 83a, would be an idle one. The rockable member 100 is in its limiting counterclockwise position against the stop 101 and the forward movement of the link 90 will merely bring a concave shoulder 102 thereof against a pin 103 of the rockable member 100, above pivot 104, and will hold it against said pin due to the long dwell of the cam 99. A link 105 connecting the rockable member 100 with a lever 106 of a device for shifting the position of. the shaft 33 on which the blanket cylinder is mounted is urged downwardly by a spring 107.

In the same general manner as in my said co-pending application the shaft 33 on which the blanket cylinder 23 rotates is eccentrically mounted in member 34 which is rotatably mounted in front plate 20 of the main frame by means of ball bearings 108. Said lever 106 is adjustably secured to a block 109 rotatable on said shaft 33. Fixed to the end of said shaft 33 by means of the screw 110 is a plate 111 having an arcuate slot through which passes an adjusting screw 114. .Said plate 111 is in the form-of a toothed sector and may be adjusted by means of a screw 113 engaging said toothed sector. After adjustment of. the position of the toothed sector on the block 109 the adjustment may be maintained by means of. the

4 adjusting screw 114 extending through said arcuate slot in the plate 111 and screwed into said block 109.

When a sheet of paper is in position for engagement by the feeler fingers 83a the shaft 83 is prevented from rocking to the same extent as would be the case if no sheet were present and the pawl 73 is maintained above the projection 84 on the lever 85. As a result when the cam 99 releases the link the link will fall and when moved to the rear a lower concave shoulder 115 on the link 90 will engage a lower pin 116. Upon the next engagement of follower 98 by the cam 99 and the rockable member will be swung in a clockwise direction until the upper arm strikes a stop 117. In this movement there is a toggle action between the rockable member 100 and the link which stretches the spring 107 and swings the lever 106 in a counterclockwise position to withdraw blanket cylinder 23 from impression cylinder 22 and plate cylinder 25a. At the same time-this movement ofthe lever 106 will act through eccentrics 32 and links 30 to swing the auxiliary frame members 26 and 27 to .the. left and separate plate cylinder 25 from blanket cylinder 23.

In the inking unit for plate cylinder 25, the pawl 53a actuating the inking roller 51 may be thrown out of operation bymeans of a lever 118 of which the right hand end may belifted by means of a link 119 in the same general way as in saidprior'ce-pending application. However, the upward movement of said.1link;119 is produced in a dilferent manner as by means of a centrally pivoted lever 120 pivoted at its rear end to the lower end of link 119 and having at its forward end a pin 121 through which it may be operated by the rearwardly' extending arm of a lever 122 on a pivot 123 on .the frame or plate 20. Said rear arm of said lever 122 is urged upwardly. by means of a spring which serves to holdthe other armof said lever in engagement with the upper part of said rockable member 100. The mechanism thus far describedis largely the same asin said co-pending applications.

As in said co-pending application the formrolls 55 may be spread apart and the molleton roller 43 maybe separated from the plate cylinder 25 by manually operated means. The impression cylinder 22, blanket cylinder 23, plate cylinder 25 and plate cylinder 25aare geared so as to be driven at the same angular rate. The cam shaft 67a is also connected by gearing to impression cylinder 22 as in said co-pending application. The cylinders 22,.23, 25 and 25a are driven from adrive shaft 123a having a gear 124 meshing with a gear 125 on the rear end of said. plate cylinder 25a. 'The gear 125 meshes with gear 126 .on .the rear end of blanket cylinder 23 and gear 126 meshes with

gears

127 and 128 on the rear ends respectively of impression cylinder, 22 and. plate cylinder The plate cylinder 25a above the blanket cylinder 23 is provided with an inking unit in which an .inking roller is driven by. a pawl 129 on a pawl carrier. 130;and engaging a ratchet wheel. 131 on the shaft 132 of the inking roller. Said pawl 129 carries a pin 133 :which may be engaged by a bent lever 134 and moved out of engagement with said ratchet 131. Said lever 134 may be raised for this purpose by means of a link 135 having a releasable connection with the upper end of a link 136 pivoted to the rearward end of a lever 137 mounted at its forward end on a pivot 138. Said lever 137 is swung about its pivot 138 by means of an upright link 139 pivoted at its upper end to lever 137 at an intermediate point and at its lower end to the right handarm of lever 122 so that rocking of said member 100 in a counterclockwise position will act to throw out the actuating means for the upper inking unit.

A shaft 140 (Fig. 1A) is driven by gearing at the rear of the machine and at its forward end carries a disk. 141 carrying an eccentric pin 142 connected to the lower end of a link 143 which at itsother end is pivotally connected with said pawl carrier 1300f the upper inking unit. From the pawl carrier 130 of the-upper inking unit a link 144 pivoted to said pawl carrier 130 extends to a pawl carrier 145 of the water unit.

In connection with the plate cylinder 25 provision is made of means operated manually for throwing out first the inking unit and then the water unit and in a reverse movement rendering the water unit effective and then the inking unit effective. The inking unit and the water supply unit connected with plate cylinder 25a can be controlled in the same general manner.

As in said co-pending application, swinging of a lever 146 to the left will separate the impression cylinder from the blanket cylinder and throw lever 147 to the right so as to engage the upper end of lever 82 to prevent full downward movement of the feeler fingers 83a. This arrangement is similar to that in said co-pending application.

Another feature of the present invention resides in arrangements for throwing either

plate cylinder

25 or 25a out of operation so as to effect printing in only one color. This is done (Fig. 6) by mounting said

cylinders

25 and 25a for rotation on

shafts

148 and 149 respectively, by ball bearings 150. Each of these shafts is mounted eccentrically in cylindrical members 151 which turn in round openings in the

members

20 and 21 of the frame. On an end of each of these shafts is fixed an arm 152 having an arcuate slot 153 through which projects a threaded pin 154. A tubular nut 155 in the form of a handle screws on said threaded pin 154 so that the arm 152 may be shifted when the nut is loose and may then be secured in position by tightening the nut. Said arm may be shifted by means of a handle 156.

It should be understood that various changes may be made and that certain features may be used without others, without departing from the true spirit and scope of the invention.

What is claimed is:

1. In a multicolor offset printing press the combination of a blanket cylinder to apply color designs to sheets and having an axis, a first plate cylinder cooperatively positioned with respect to the blanket cylinder approximately at the top thereof, damping and inking means above the first plate cylinder for damping and inking the latter, a second plate cylinder cooperatively positioned with respect to the blanket cylinder approximately on a horizontal plane through the axis of the blanket cylinder, damping and inking means disposed on the opposite side of the second plate cylinder from the blanket cylinder for damping and inking the second plate cylinder, the plate cylinders to apply color designs on said blanket cylinder, an impression cylinder cooperatively positioned with respect to the blanket cylinder approximately diametrically opposite from the two plate cylinders, a sheet entrance path extending to the top of the impression cylinder, means for driving all of said cylinders together and at the same angular speed, means mounting the blanket cylinder for movement towards and away from the impression cylinder and the first plate cylinder, means mounting solely one of the plate cylinders for movement towards and away from the blanket cylinder, shifting means connected with the movable mounting means to separate the blanket cylinder from the impression cylinder and the first plate cylinder and to separate the movable plate cylinder from the blanket cylinder and restore them to cooperative position, and sheet-controlled means connected with the shifting means for effecting operation of the movable mounting means.

2. In a multicolor offset printing press said combination according to claim 1 wherein said means for effecting separation comprises means for shifting said blanket cylinder from said impression cylinder and one of said plate cylinders, and means for shifting another plate cylinder a distance greater than the movement of the blanket cylinder to separate it from said blanket cylinder during such shifting of the blanket cylinder.

3. In a multicolor offset printing press, said combination according to claim 2 wherein said means for shifting another plate cylinder to separate it from said blanket cylinder comprises a movable frame carrying such plate cylinder and said means for shifting another plate cylinder being connected with said frame to separate the plate cylinder carried thereby from said blanket cylinder and to, restore operative relation therebetween.

4. In a multicolor offset printing press, said combination according to claim 3 wherein said movable frame is pivoted to swing about an axis and such separation and restoration are effected by rocking said frame.

5. In a multicolor offset printing press, said combination according to claim 3 wherein said means for shifting said blanket cylinder comprises a shaft on which the blanket cylinder rotates, eccentric cylindrical members fixed on the blanket cylinder shaft, and rotatably mounted in corresponding fixed bearings, a second set of eccentrics fixed on said shaft, and operating links pivoted in one end to said movable frame and at their other ends mounted on the eccentrics of said second set to move said frame.

6. In a multicolor printing press the combination of an impression cylinder, blanket cylinder, two plate cylinders and gearing connecting said cylinders; an inking unit for each plate cylinder comprising an inking roll with a ratchet wheel and a pawl carrier for actuating the same; a cam shaft and means operated by said cam shaft for separating said blanket cylinder from the rest of said cylinders; means operated by said cam shaft for operating said pawl carriers; pawl retracting levers; a link for swinging one of said levers counter-clockwise to withdraw the corresponding pawl of a first unit and a lever connected at one end to the lower end of said link and having at its other end a laterally projecting pin; a second lever overlying said pin and having a central pivot, means for lifting the other end of said lever upon shifting of the blanket cylinder and a link connected to said lever; and a pawl retracting lever arranged to be swung in a clockwise direction by upward movement of the last mentioned link to shift the pawl of the second ratchet.

7. In a multicolor offset printing press said combination as in claim 3 including a shaft mounting each of said plate cylinders, eccentric means for at least one of said shafts, and manual means connected with the eccentric means to turn the same and move the plate cylinder away from the blanket cylinder.

8. In a multicolor offset printing press said combination as in claim 7 including eccentric means for said shaft for each of said plate cylinders, and manual means connected with each eccentric means to turn the same to move each plate cylinder away from the blanket cylinder.

9. In an offset printing press the combination of an impression cylinder, a blanket cylinder contacting the impression cylinder, a plate cylinder contacting the blanket cylinder approximately diametrically opposite the impression cylinder, a movable frame mounting the plate cylinder, means for shifting said blanket cylinder comprising a shaft on which said blanket cylinder rotates, eccentric cylinder members fixed on the blanket cylinder shaft and rotatably mounted in corresponding fixed bearings, a second set of eccentric cylinder members fixed on said shaft, and operating links connected between said movable frame and said second set of eccentrics to move said frame a distance which is the combined movement of the two sets of eccentric cylinder members.

10. In an oifsetprinting press the combination as in claim 9 including a delivery cylinder contacting the impression cylinder and adjacent to the blanket cylinder.

11. In an offset printing press the combination as in claim 9 including means effective upon absence of a sheet at the impression cylinder to turn said shaft to effect separation between the blanket cylinder and the impression cylinder and separation between the blanket cylinder and the plate cylinder and to turn said shaft to bring said