US3611921A

US3611921A - Sheet-fed offset printing machine having a numbering device

Info

Publication number: US3611921A
Application number: US23376A
Authority: US
Inventors: Hans-Georg Jahn
Original assignee: Heidelberger Druckmaschinen AG
Current assignee: Heidelberger Druckmaschinen AG
Priority date: 1969-03-28
Filing date: 1970-03-27
Publication date: 1971-10-12
Anticipated expiration: 1988-10-12
Also published as: AT297055B; JPS4813602B1; CH496548A; NL6918385A; GB1271607A; NL139264B; SE355993B; DE1915921A1; DE1915921B2; FR2033696A5

Abstract

A sheet-fed offset printing machine having an impression cylinder from which a sheet is being imprinted includes a revolvable endless chain delivery having a pair of opposing sprocket wheels mounted on respective shafts, a gripper bridge on the chain delivery for gripping and removing the sheet from the impression cylinder, a numbering device including numbering mechanisms mounted on one of the sprocket wheel shafts so as to cover part of the periphery of the respective sprocket wheel and a counterpressure roller adjacent and cooperating with the numbering mechanisms, the part of the sprocket wheel periphery being coverable by the sheet being removed from the impression cylinder, an ink carrier segment rotatable about the one sprocket wheel shaft and located between the runs of the endless chain delivery, the segment having an ink-carrying cover surface, an ink fountain mounted outside the endless chain delivery and including a lifter roller engageable with the cover surface through revolving zones of the endless chain delivery, that are free of superposed sheets and are located directly upstream of the gripper bridge, for supplying ink to the cover surface, and mutually cooperating inking roller and friction roller located between the runs of the endless chain delivery, the inking roller having an ink-carryng covering alternately engageable periodically with the cover surface of the ink carrier segment and with printing surfaces of the numbering mechanisms.

Description

United States Patent Hans-Georg Jahn Wiesloch, Gennany 23,376

Mar. 27, 1970 Oct. 12, 1971 Heidelberger Druekmasehinen Aktiengesellsehaft Heidleberg, Germany Mar. 28, 1969 Germany Inventor Appl. No. Filed Patented Assignee Priority SHEET-FED OFFSET PRINTING MACHINE HAVING A NUMBERING DEVICE 7 Claims, 5 Drawing Figs.

US. Cl

101/77 B411 47/46 Field of Search 101/76, 77,

References Cited UNITED STATES PATENTS 8/ 193 3 Allen 2/1951 Aberle..... 6/1958 Rothoff 7/1962 Janke Primary Examiner-William B. Penn Attorneys-Curt M. Avery, Arthur E. Wilfond, Herbert L.

Lerner and Daniel J. Tick ABSTRACT: A sheet-fed offset printing machine having an impression cylinder from which a sheet is being imprinted includes a revolvable endless chain delivery having a pair of opposing sprocket wheels mounted on respective shafts, a gripper bridge on the chain delivery for gripping and removing the sheet from the impression cylinder, a numbering device including numbering mechanisms mounted on one of the sprocket wheel shafts so as to cover part of the periphery of the respective sprocket wheel and a counterpressure roller adjacent and cooperating with the numbering mechanisms, the part of the sprocket wheel periphery being coverable by the sheet being removed from the impression cylinder, an ink carrier segment rotatable about the one sprocket wheel shaft and located between the runs of the endless chain delivery, the segment having an ink-carrying cover surface, an ink fountain mounted outside the endless chain delivery and including a lifter roller engageable with the cover surface through revolving zones of the endless chain delivery, that are free of superposed sheets and are located directly upstream of the gripper bridge, for supplying ink to the cover surface, and mutually cooperating inking roller and friction roller located between the runs of the endless chain delivery, the inking roller having an ink-carryng covering alternately engageable periodically with the cover surface of the ink carrier segment and with printing surfaces of the numbering mechanisms.

SHEET-FED OFFSET PRINTING MACHINE HAVING A NUMBERING DEVICE My invention relates to sheet-fed offset printing machine having a numbering device, and more particularly, such a machine wherein the numbering device comprises a plurality of numbering mechanisms that are mounted on a sprocket wheel shaft of an endless chain delivery, the numbering mechanisms cooperating with a counterpressure roller which is located downstream of the impression cylinder of the offset printing machine in the travel direction of the sheet-fed therethrough.

Sheet-fed ofi'set printing machines with auxiliary numbering devices have been known heretofore wherein the numbering devices are located directly at the impression cylinder of the offset printing machine. The sheet fed from the impression cylinder is numbered by the numbering devices either before or after the nonnal printing operation. Such an arrangement of the numbering mechanisms is possible, however, for reasons of servicing and space requirements, only in such printing machines that are provided with an impression cylinder that is twice, threefold or fourfold the size of the blanket and form cylinders.

Furthermore, sheet-fed offset printing machines with a chain delivery and cylinders of equal size have been known heretofore wherein an auxiliary numbering device is adjustably provided on the sprocket wheel shaft located downstream of the impression cylinder of the offset printing machine. A small inking mechanism disposed between the path of the gripper bridges supplies the numbering mechanisms with ink through transfer or inking rollers. The newly imprinted sheet gripped by the gripper bridge is numbered during the revolving thereof about the sprocket wheel shaft, a counterpressure roller mounted outside the travel path of the sheet pressing and the passing sheet against the ink-carrying digits of the numbering mechanisms.

This construction of the numbering device is possible only in such sheet-fed offset printing machines whose paths for the sheet delivery provides sufficient room for the numbering mechanism. In addition, the location of the numbering inking mechanism within the path is disadvantageous because it is impossible to fill the ink fountain with ink and to regulate the ink feed by actuating the zone screws during operation of the sheet-fed offset printing machine.

It is accordingly an object of my invention to provide sheetfed offset printing machine having a numbering device so that the inking mechanism for the numbering device in the chain delivery is more readily accessible for servicing, and the productivity of the machine is thereby increased. More specifically, it is an object of my invention to provide such an offset printing machine with a numbering device which avoids the necesity for stopping operation of the machine with a consequent loss of production whenever it is necessary to fill the ink and when it is necessary to control the zone screws of the inking fountain during the printing operation.

With the foregoing and other objects in view I provide, in accordance with my invention, in a sheet-fed offset printing machine having an impression cylinder from which a sheet is being imprinted, a revolvable endless chain delivery including a pair of opposing sprocket wheels mounted on respective shafts, a gripper bridge on the chain delivery for gripping and removing the sheet from the impression cylinder, a numbering device including numbering mechanisms mounted on one of the sprocket wheel shafts so as to cover part of the periphery of the respective sprocket wheel and a counter pressure roller adjacent and cooperating with the numbering mechanisms, the part of the sprocket wheel periphery being coverable by the sheet being removed from the impression cylinder, an ink carrier segment rotatable about the one sprocket wheel shaft and located between the runs of the endless chain deliver, the segment having an ink-carrying cover surface, an ink fountain mounted outside the endless chain delivery and comprising an lifter roller engageable with the cover surface through revolving zones of the endless chain delivery, that are free of superposed sheets and are located directly upstream of the gripper bridge, for supplying ink to the cover surface, and mutually cooperating inking roller and friction roller located between the runs of the endless chain delivery, the inking roller having an ink-carrying covering alternately engageable periodically with the cover surface of the ink carrier segment and with printing surfaces of the numbering mechanisms.

With a device according to my invention, filling of the ink as well as actuation of the zone screws during operation of the sheet-fed offset printing machine is possible without any difficulty. Moreover, considerable space is saved between the runs of the endless chain delivery. In accordance with another feature of the invention and in order to simplify the control of the counterpressure roller and the lifter roller, the lifter roller of the inking fountain and the counterpressure roller for the numbering mechanisms are mounted respectively at one end of a double armed lever and are alternately pivotal in a circular path that is periodically traversable both by the ink-carrying covering surface as well as by the printing surface of the numbering mechanisms.

In accordance with yet another feature of my invention, the ink-carrying covering surface, as viewed over the width of the sprocket wheel shaft, is divided into individual partial covering surfaces accommodated to substantially the width of the printing surfaces of the respective numbering mechanisms.

Such an accommodation of the partial covering surfaces to the expanse of the printing mechanism of the respective numbering mechanism extending in direction of the sprocket wheel shaft permits the use of coaxially disposed self-containing or sealed inking fountain segments from which each of the respective numbering mechanisms is supplied with ink through the respective partial covering surface.

This construction of the inking mechanism of my invention is especially favorable if the numbering of a sheet is to be effected in different colored inks.

Other features which are considered as characteristic for the invention are set forth in the appended claims.

Although the invention is illustrated and described herein as embodied in sheet-fed offset printing machine having a numbering device, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.

The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which:

FIG. I is a diagrammatic front elevational view of a sheetfed offset printing machine for single color printing with an endless chain delivery and a numbering mechanism according to my invention;

FIG. 2 is an enlarged fragmentary view of FIG. 1 showing the numbering mechanism in another phase thereof;

FIG. 3 is another view of FIG. 2 showing a counterpressure roller applied thereto:

FIG. 4 is a fragmentary view of FIG. 1 wherein the inkwell is located above the endless chain delivery device; and

FIG. 5 is another embodiment of the offset printing machine of FIG. 1 wherein a sheet feed pile is located above the sheet delivery pile.

Referring now to the drawings and particularly to FIG. I thereof, there is shown a sheet-fed offset printing machine having a plate cylinder 1 which is dampened by a dampening mechanism 2 and is supplied with ink from an inking system 3. Vertically below the plate cylinder 1, there is located a blanket cylinder 4 which cooperates with an adjacent counterpressure or impression cylinder 5. A sheet 9 is supplied to the impression cylinder 5 from a feed pile 6 over a feed table 7 and an oscillating gripper 8 to the impression cylinder 5 and, after the sheet 9 has been provided with an imprint or impression from the transfer or blanket cylinder 4, it is removed by a gripper bridge of an endless chain deliver 11 from the counterpressure or impression cylinder 5. The endless chain delivery 11 supplies the imprinted sheet to the delivery pile 12.

Several numbering mechanisms 14 are mounted on the sprocket wheel 13 of the sprocket wheel pair 13' which follows the counterpressure cylinder 5. All of these numbering mechanisms 14 are located on a circular segment about the sprocket wheel shaft 13 and, in fact, in that region of the periphery which carries the imprinted surface of a sheet 9 when the sheet 9 is being removed from the counterpressure cylinder 5. At the opposite segment of the periphery about the sprocket wheel shaft 13, an ink carrier segment 15 is fixedly mounted. The segment 15 is provided with a shell or surface 16 which is disposed in a circular path which is described, during rotation of the numbering mechanisms 14 about the sprocket wheel shaft 13, by the printing surface thereof.

In the vicinity of the circular travel path of the numbering mechanisms 14 there is provided a counterpressure roller 17, which is located downstream from the counterpressure cylinder 5 and which has a rubber covering on the peripheral surface thereof. The counterpressure roller 17 is rotatably mounted at one end of the pivotal bell crank or double armed lever 18. At the other end of the bell crank 18 from the location of the counterpressure roller 17, there is rotatably mounted a lifter roller which cooperates with an ink fountain roller 20 of an ink fountain 21. This ink fountain 21 is provided with zone screws 22 for adjusting the ink supply.

An inking roller 23 is mounted within the travel path of the gripper bridge 10 so that the cover or peripheral jacket thereof can come into contact both with the covering surface 16 as well as with the printing surfaces of the numbering mechanisms 14. A friction roller 24 is located at the side of the inking roller 23 facing away from the sprocket wheel shaft 14 and is operatively connected with the inking roller 23. The inking roller 23 as well as the friction roller 24 are accessible through an opening 25 in the lateral frame 26 of the sheet-fed offset printing machine of my invention.

The operation of the aforedescribed apparatus is as follows:

The sheet 9 which is imprinted by the cooperation of the blanket cylinder 4 and the impression or counterpressure cylinder 5 is removed by the grippers of the impression cylinder 5 by a gripper bridge 10 of the chain delivery system 11 and is guided in a circular arc about the sprocket wheel shaft 13. The imprinted surface of the sheet 9 thus faces in direction toward the sprocket wheel shaft 13. Consequently, the numbering mechanisms 14 disposed on the shaft 13, in cooperation with the adjacent counterpressure roller 17, can imprint one or more numbers on the sheet 9 depending upon the particular adjustment or arrangement of numerals thereon, as can be seen in FIG. 3. If the end of the sheet 9 has passed the counterpressure roller 17, the printing surface 29 of the last one of the numbering mechanisms 14 will also have been passed by the counterpressure roller 17.

Thereafter, the double armed lever or bell crank 18 is actuated, the counterpressure roller 17 is pivoted away and the lifter roller 19, which has been coated with ink by the ink fountain roller 20, is placed against the covering surface 16, as shown in FIG. 2. The covering surface 16 of the ink carrier segment 15, which has passed by the ink fountain 21 in the interim due to the corresponding rotation of the sprocket wheel shaft 13, is thus provided with a film of ink which is trans ferred to the inking roller 23 and distributed by the friction roller 24 after further rotation of the sprocket wheel shaft 13. For each pass of the covering surface 16 of the ink carrier segment 15, the adjusted printing surfaces 29 of the numbering mechanisms 14 remove part of the ink from the inking roller 23.

The ink fountain 21 is located beneath the delivery pile table 7 and is readily accessible so that subsequent filling of the ink and actuation of the zone screws 22 can be effected without difficulty during the operation of the sheet-fed offset printing machine.

Another embodiment of my invention is shown in FIG. 4 in the form of an offset printing machine which has a construction which is almost the same as that of FIG. 1. The primary difference is that the ink fountain 21 is located above the conveyor chain delivery system 11 rather than below the same as in the embodiment of FIG. 1.

The form cylinder 1 cooperating with the dampening mechanism 2 and the inking system 3 transfers the impression from the form to the blanket cylinder 4 which, in turn, in cooperation with the impression cylinder 5, imprints the sheet 9 supplied by the feed pile 6 above the feed table 7 and pivoting grippers 8. The chain delivery system 11 removes the sheet 9 from the impression cylinder 5 with the aid of the gripper bridge 10 and feeds it to the delivery pile 12.

The numbering mechanisms 14 are located on the sprocket wheel shaft 13 in exactly the same manner as with the aforedescribed embodiments of my invention.

The sheet 9 guided by the gripper bridge 10 is pressed against the printing surfaces 29 of the numbering mechanisms 14 by a pivotally mounted counterpressure roller 17 provided with rubber peripheral covering.

The inking of the printing surfaces 29 of the numbering mechanisms 14 is taken over by an inking roller 23 disposed between the courses 28 of the endless chain delivery conveyor 11, the ink-carrying covering of the inking roller 23 being disposed in the circular path described by the printing surfaces 29 of the numbering mechanisms 14.

Moreover, the inking roller 23 is in constant contact with the friction roller 24. Both of the

aforedescribed rollers

23 and 24 are readily accessible through an opening 25 in the side frame 26.

An ink carrier segment 15, which is rotatably mounted on a separate shaft 30 between the inking roller 23 and the upper course 28 of the gripper bridges, and supplies the inking roller 23 with ink. The just-mentioned shaft 30 extends parallel to the sprocket wheel shaft 13. The covering surface 16 of the ink carrier segment 15 periodically comes into contact with the inking roller 23. Through the zones of the upper course 28 of the delivery system 11 which are free of sheets, the covering surface 16 is supplied with ink from the lifter roller 19 of an ink fountain 21 disposed above the chain delivery conveyor 11. through the intermediary of the ink fountain roller 20. Zones of the upper course 28 which are free of sheets are located respectively upstream of the gripper bridge 10 of the chain delivery system 11. When the gripper bridge 10 reaches the ink carrier segment 15, it is immersed in a recess 33 formed in the segment 15 without damaging the covering surface 16 of the segment 15. The ink fountain 21 is provided with zone screws 22 for controlling the inking and can be filled and adjusted from the feed end of the machine during the operation.

A third embodiment of the invention, which is shown in FIG. 5, differs from that of FIGS. 1 and 4 by the specific structure of the sheet-fed offset printing machine in that the form cylinder 1 and the blanket cylinder 4 of the embodiment of FIG. 5 are disposed substantially horizontally while the impression cylinder 5 is located above the blanket cylinder 4 at an inclined angle with respect to the horizontal. Sheets 9 are supplied to the impression cylinder 5 from the feed pile 6 and over the feed table 7 by pivoting grippers 8. The feed pile 6 is disposed above the delivery pile 12, however, in this case. Both

piles

6 and 12 are separated from one another by the endless chain delivery conveyor 11. Because the feed pile 6 and in the delivery pile 12 are provided at one end of the offset printing machine, the impression cylinder 5 must have a rotational sense directed opposite to the rotary direction of the impression cylinder 5 of the aforedescribed machines of FIGS. 1 and 4. For this reason the rotary direction of the chain delivery system 11 is also reversed, whereby the sheets 9 are removed above the upper course 28 by the impression cylinder 5 and are placed on the delivery pile 12 after passing around the second sprocket wheel shaft 27. Each sheet 9 is thus not passed around the first sprocket wheel shaft 13,

which is located directly downstream from the impression cylinder 5, but rather around the sprocket wheel shaft 27 located above the delivery pile 12. This is the reason for mounting the numbering mechanisms 14 and the inking carrier 15 on the second sprocket wheel shaft 27. The arrangement thereof and also the mounting of the inking roller 23 as well as the friction roller 24 corresponds to the principle of, for example, the embodiment of FIG. 1 wherein the numbering mechanisms 14 and the ink carrier segment 15 are secured on the sprocket wheel shaft 13. The counterpressure roller 17 as well as the lifter roller 19 are again located on the double armed lever or bell crank 18 above the sprocket wheel pair 27'. By actuating the double armed lever 18, both the counterpressure roller 17 and the lifler roller 19 can be alternately pivoted respectively into the travel path of the printing surfaces 29 and into the circular path described by the covering surface 16. The lifter roller 19 receives the ink from the ink fountain 21 through the ink roller 20 and passes it on to the covering surface 16. The inking fountain 21 is again provided in a conventional manner with zone screws 22. It is readily accessible at the supply end of the machine above the delivery pile l2 and is fastened below the feed pile 6 on the machine frame 32. The ink fountain 21 can be filled during the operation of the machine, and similarly, the zone screws 22 can be adjusted at any time i.e., also during operation condition of the machine, for controlling the ink feed.

It is of course apparent that there are manifold additional variations that are conceivable for the apparatus of the invention in the instant application. For example, a respective inking mechanism 14 and a part of the covering surface 16 can be axially adjustably mounted on a common ring on the sprocket wheel shaft 13 as a sealed unit. Also, the ink fountain 21 with the ink fountain roller 20 thereof as well as the lifter roller 19 can be divided individually in closed segments from which each is coordinated with one of the axially adjustable numbering mechanisms. The individual segments of the ink fountain 21 can be provided with different colored inks.

Iclaim:

1. In a sheet-fed offset printing machine having an impression cylinder from which a sheet is being imprinted, a revolvable endless chain delivery including a pair of opposing sprocket wheels mounted on respective shafts, a gripper bridge on said chain delivery from gripping and removing the sheet from the impression cylinder, a numbering device including numbering mechanisms mounted on one of said sprocket wheel shafts so as to cover part of the periphery of the respective sprocket wheel and a counterpressure roller adjacent and cooperating with said numbering mechanism, said part of said sprocket wheel periphery being coverable by the sheet being removed from the impression cylinder, and ink carrier segment rotatable about an axis and located between the runs of said endless chain delivery, said segment having an ink-carrying cover surface, an ink fountain mounted outside said endless chain delivery and comprising a lifter roller engageable with said cover surface through revolving zones of said endless chain delivery, that are free of superimposed sheets and are located directly upstream of said gripper bridge, for supplying ink to said cover surface, and mutually cooperating inking roller and friction roller located between the runs of said endless chain delivery, said inking roller having an ink-carrying covering alternately engageable periodically with the cover surface of said ink carrier segment and with printing surfaces of said numbering mechanisms.

2. In a sheet-fed offset printing machine according to claim 1, said lifter roller and said counterpressure' roller being mounted respectively at the ends of a pivotally mounted double armed lever and being alternately pivotable in a circular path periodically traversable both by said ink-carrying cover surface of said ink carrier segment as well as by said printing surfaces of said numbering mechanisms.

3. In a sheet-fed offset printing machine according to claim 1, said ink-carrying cover surface of said ink carrier segment,

as viewed over the width of said sprocket wheel shaft, is subdivided into individual partial cover surfaces accommodated substantially to the width of the printing surfaces of the respective numbering mechanisms.

4. In a sheet-fed offset printing machine according to claim 1, said sprocket wheel shaft on which said numbering mechanisms are mounted, being located downstream of the impression cylinder, said ink carrier segment being also mounted on said sprocket wheel shaft in peripheral segments of said sprocket wheel that are free of said numbering mechanisms and being adapted to supply ink to said inking roller through said cover surface of said ink carrier segment, said lifter roller being mounted in the vicinity of said sprocket wheel outside the paths of said gripper bridge along the runs of said chain delivery and engageable with said cover surface for inking the same at each pass thereof, said lifter roller supplying ink from an ink fountain roller associated with an ink fountain.

5. In a sheetfed printing machine according to claim 4, said ink fountain is secured to a side frame of the machine outside of said chain delivery and is accessible from a servicing location below a sheet feed delivery table of the machine.

6. In a sheet-fed offset printing machine according to claim 1, said ink fountain being located above said chain delivery, said ink carrier segment being mounted on a separate shaft extending parallel to said sprocket wheel shaft so that said lifter roller of said ink fountain supplies said cover surface of said ink carrier segment periodically with ink from above.

7. In a sheet-fed offset printing machine according to claim 1 wherein a sheet feed pile is located above the upper part of the run of said chain delivery, said numbering mechanisms and said ink carrier segment being mounted on the sprocket wheel shaft located most distant from the impression cylinder, said ink fountain being mounted at a side from of the machine above the respective sprocket wheel so that it is readily accessible from the side of the machine at which the sheet pile is located.

Claims

2. In a sheet-fed offset printing machine according to claim 1, said lifter roller and said counterpressure roller being mounted respectively at the ends of a pivotally mounted double armed lever and being alternately pivotable in a circular path periodically traversable both by said ink-carrying cover surface of said ink carrier segment as well as by said printing surfaces of said numbering mechanisms.

3. In a sheet-fed offset printing machine according to claim 1, said ink-carrying cover surface of said ink carrier segment, as viewed over the width of said sprocket wheel shaft, is subdivided into individual partial cover surfaces accommodated substantially to the width of the printing surfaces of the respective numbering mechanisms.

5. In a sheet-fed printing machine according to claim 4, said ink fountain is secured to a side frame of the machine outside of said chain delivery and is accessible from a servicing location below a sheet feed delivery table of the machine.