US2508844A - Sheet handling mechanism for printing machines - Google Patents

Description

May 23, 1950 F. SPENCE ETAL SHEET HANDLING MECHANISM FOR PRINTING MACHINES 4 Sheets-Sheet 1 Filed Nov. 16, 1946 May 23, 1950 F. sPENcE EIAL 2,508,844

SHEET HANDLING MECHANISM FOR PRINTING MACHINES Filed Nov. 16, 1946 4 Sheetsi-Sheet 2 May 23, 1950 v s Nc A 2,508,844

SHEET HANDLING MECHANISM FOR PRINTING MACHINES Filed Nov. 16. 1946 4 Sheets-Sheet 3 May 23, 1950 F. SPENCE ETAL v SHEET HANDLING MECHANISM FOR PRINTING MACHINES 4' Sheets-Sheet 4 Filed Nov. 16, 1945 Patented May 23, 1950 SHEET HANDLING MECHAN ISM FOR PRINTING MACHINES Fred Spence, Sale, and John Wallace Jakeman, Timperley, England, assignors to Linotype and Machinery Limited, London, England, a company of Great Britain 7 Application November 16, 1946, Serial No. 710,250 In Great Britain November 19, 1945 Claims. (01. 101-278) This invention relates to printing machines wherein a sheet fed to an impression cylinder is carried thereby into contact with a printing surface and, after printing, the sheet is delivered from the impression cylinder. The invention is particularly applicable to a printing machine wherein the impression cylinder co-operates with a printing surface mounted on a reciprocating printing bed, the impression cylinder normally remaining continuously in position for receiving an impression.

According to the invention there is provided a printing machine having a reciprocating printing bed carrying a printing surface and having an impression cylinder co-operating therewith wherein the impression cylinder is provided with a plurality of separate surfaces comprising an impression surface which carries a sheet into contact with the printing surface for printing, a transfer surface to which the sheet is transferred after printing for delivery from the machine, and a surface which is cut-away to avoid contact with the surface on the printing bed during the reverse or non-printing stroke thereof. The sheet may be taken from the impression surface and transferred to the transfer surface by means of a transfer cylinder which makes one revolution while taking a sheet from the impression surface, another revolution while transferring the sheet to the transfer surface and an idle revolution while co-operating with the cut-away surface of the impression cylinder.

The transfer cylinder may be provided with sheet grippers which are operated so that during one revolution a sheet is taken from the impression surface and during the next revolution a sheet is released and transferred to the transfer surface, said grippers remaining inoperative during the idle revolution of the transfer cylinder. Operation of the sheet grippers. may be controlled by a cam provided on a driven shaft on which the driven transfer cylinder is freely mounted,

the shaft making one revolution for three revolutions of the transfer cylinder.

The invention will now be described in greater fer cylinder ll.

detail with reference to the accompanying drawings, which illustrate one form which it may assume.

In the said drawings:

Figure 1 is a side elevation of the relevant parts of a printing machine constructed according to the present invention;

Figure 2 is an enlarged plan view of the transfer cylinder and its associated operating mecha- 1 Figure 3 is an enlarged side view of the cams by means of which the transfer cylinder grippers are operated;

Figure 4 is a section taken on the line IV--IV of Figure 3;

Figure 5 is a section taken on the line V-V of Figure 2; a

Figure 6 is a side View of the transfer cylinder.

Referring to Figure 1, a printing surface comprising a type forme I is mounted on a printing bed 2 which is reciprocated along tracks 3 carried by a machine frame 4. The upper part of the machine frame 4 has side members 5 carrying eccentric bearings 6 for the shaft 1 of an impression cylinder 8 to which sheets are fed from the feedboard F for printing. The bearings 6 are normally stationary so that the impression cylinder 8 remains continuously in position for receiving an impression. If it is desired to trip the impression cylinder 8 out of contact with the type forme l (as in the event of the incorrect feeding of a sheet), the eccentric bearings 6 are rotated through movement of the rod 9 and arm In connected to each bearing.

The diameter of the impression cylinder 8 is three times that of a transfer cylinder II with which it cooperates, and the circumference of the impression cylinder 8 is divided into three parts comprising an impression surface I2, 9. transfer surface l3 and a cut-away portion [4. To provide the cut-away portion M a part of the impression cylinder bearers I5 is removed which would otherwise contact with the bearers I6 on the printing bed 2 during the reverse, or nonprinting stroke of the bed, and a part of the surface of the impression cylinder 8 is made approximately one-eighth of an inch below the impression surface I2 so that the type forme I on the bed 2 can pass freely during the reverse stroke of the bed without contacting with the surface of the impression cylinder 8.

The impression cylinder 8 is driven through gearing by the main driving shaft of the machine, and is provided with a gear [1 which meshes with a gear I8 on the body of the trans- For taking a sheet on the impression surface l2 and subsequently delivering it to the transfer cylinder 1 I, grippers I9 (hereinafter referred to as impression cylinder grippers) are mounted on a gripper shaft 20 carried by the impression cylinder 8, said gripper shaft 20 being provided with a tumbler 2| engaging opening and closing I pins 22, 23, carried by the machine frame 4. For

taking a sheet from the transfer cylinder II on to the impression cylinder 8 brings the impression cylinder transfer grippers 26 to a position in which they are opened to allow the sheet to be taken by the grippers 24 on the delivery chain 25. While the sheet is being delivered, the second sheet fed to the impression surface i2 is receiving an impression from the type forme l on the printing bed 2 which has commenced its printing stroke. Also at this time the cut-away por- -tion M of the impression cylinder 8 is co-operat rate arcuate transfer surface, both of said surfaces having equal radii, and a separate arcuate surface having a radius which is less than that of the said impression and transfer surfaces to permit a reverse non-printing stroke of the printing bed, sheet gripper mechanism on said impression cylinder and associated with said impression and transfer surfaces, means for operating said sheet gripper mechanism to receive and release a sheet on said impression surface and to receive and release a sheet on said transfer surface, a transfer cylinder co-operating with said impression cylinder and having formed thereon a sheet-receiving surface, sheet gripper mechanism on said transfer cylinder and associated with said sheet receiving surface, means for operating said sheet gripper mechanism on the transfer cylinder to receive a sheet released from the impression surface on the impression cylinder and to release a sheet to be received by the transfer surface of the impression cylinder, means for feeding a new sheet to said impression surface on the impression cylinder after a previous sheet has been completely transferred therefrom to the sheet receiving surface on the transfer cylinder, and means for delivering such previous sheet which is released from the transfor surface on the impression cylinder after being completely transferred thereto from the sheet-receiving surface on the transfer cylinder.

2. In a printing machine, the combination with a reciprocating printing bed carrying a type forme of a rotating shaft, an impression cylinder mounted on said shaft and being successively provided around the periphery thereof with an arcuate impression surface, a separate arcuate transfer surface, both of said surfaces having equal radii, and a separate arcuate surface having a radius which is less than that of the said impression and transfer surfaces to permit a reverse non-printing stroke of the printing .bed, sheet gripper mechanism on said impression cylinder and associated with said impression and transfer surfaces, means for operating said sheet gripper mechanism to receive and release a sheet on said impression surface and to receive and release a sheet on said transfer surface, a transfer cylinder cooperating with said impression cylinder and having formed thereon a sheet-receiving surface, said transfer cylinder having a diameter which is approximately one-third the diameter of the said impression cylinder, a transfer cylinder shaft on which the transfer cylinder is mounted, said shaft being located approximately in the same horizontal plane as the shaft on which the said impression cylinder is mounted, sheet gripper mechanism on said transfer cylinder and associated with said sheet receiving surface, means for operating said sheet gripper mechanism on the transfer cylinder to receive a sheet released from the impression surface on the impression cylinder and to release a sheet to be received by the transfer surface of the impression cylinder, means for feeding a new sheet to said impression surface on the impression cylinder after a previous sheet has been completely transferred therefrom to the sheet receiving surface on the transfer cylinder, and means for delivering such previous sheet which is released from the transfer surface on the impression cylinder after being completely transferred thereto from the sheet-receiving surface on the transfer cylinder.

3. In a printing machine, the combination with a reciprocating printing bed carrying a type forme of a rotating impression cylinder which is successively provided around the periphery thereof with an arcuate impression surface, a separate arcuate transfer surface, both of said surfaces having equal radii, and a separate arcuate surface having a radius which is less than that of the said impression and transfer surfaces to permit a reverse non-printing stroke of the printing bed, sheet gripper mechanism on said impression cylinder and associated with said impression and transfer surfaces, means for operating said sheet gripper mechanism to receive and release a sheet on said impression surface and to receive and release a sheet on said transfer surface, a transfer cylinder driven by said impression cylinder and having formed thereon a sheet-receiving surface, sheet gripper mechanism on said transfer cylinder and associated with said sheet-receiving surface, a shaft on which said transfer cylinder is loosely mounted, means for rotating said shaft by rotation of said transfer cylinder, cam mechanism on said shaft controlling the operation of the said sheet gripper mechanism on the transfer cylinder to permit said gripper mechanism to receive a sheet released from the impression surface on the impression cylinder and to release a sheet to be received by the transfer surface of the impression cylinder, means for feeding a new sheet to said impression surface on the impression cylinder after a previous sheet has been completely transferred therefrom to the sheet-receiving surface on the transfer cylinder and means for delivering such previous sheet which is released from the said transfer surface on the impression cylinder after being completely transferred thereto from the sheet-receiving surface on the transfer cylinder.

4. In a printing machine, the combination with a reciprocating printing bed carrying a type forme of a rotating shaft, an impression cylinder mounted on said shaft and being successively provided around the periphery thereof with an arcuate impression surface, a separate arcuate transfer surface, both of said surfaces having equal radii, and a separate arcuate surface having a radius which is less than that of the said impression and transfer surfaces to permit a reverse non-printing stroke of the printing bed, sheet gripper mechanism on said impression cylinder and associated with said impression and transfer surfaces, means for operating said sheet gripper mechanism to receive and release a sheet on said impression surface and to receive and release a sheet on said transfer surface, a transfer cylinder driven by said impression cylinder and having formed thereon a sheet-receiving surface,

- byrotatien of: said transfer -cy1inder, :eams e- I cured to said shaft and-centrol-lingthe tipr ation of-the sai'd "sheet gnipper meehanism(Sm-the tz a ns- :terey1'inder to permit sa'id gripper mechanism to :receivea sh'eet releasjed from the z'mpr'essidm sur- 4ace onthe impression cylinderandto release a :sheet Ito be received by the transfer -sui'f 36e df the impression cylinder, meansior feedifiga 116w :sheet -to said impressiom surfa-ce en the impi ession cylinderafter a-previous sheet-has beencomptetely transferred therefrom to'the'sheet-reeeivdrig surface on-thetransfer cylindez and means for delivering such: iafvidus sheet *whlch reqased from the said transfer sufface on the 1mpi'e'ssic m cylinder after Being "eumpletel'y transfrrd thereto from bhe sheet-r'eceiving surfae 0n the transfer cylinder.

5. In'a; pr intmg machine, -the combination according to c1aim4 including a framework in'which -the -transer-cy1inder shaft and the fixed gear wheel -are mounted, 'said framewbrk being "dewen-ably seeured tn the printing machineframework.

FRED SPENGE. JOHN WALLACE JAKEMAN.

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