Automatic offset printing press

Claim 2

An automatic offset printing press comprising, in combination, a master cylinder for supporting a master plate; an inking means for the master plate; a blanket cylinder to receive an ink image transferred from a plate on said master cylinder; a cleaning means for said blanket cylinder; an impression cylinder operable to press copy sheets against said blanket cylinder; means operable to rotate said cylinders in respective directions; a timer operator operable by rotation of one of said cylinders at the end of each revolution thereof; a first mechanical timer operable by said operator to initiate, in a timed sequence corresponding to revolutions of said one cylinder, inking of the master plate, transfer of the ink image to said blanket cylinder, and feeding of the copy sheets between said blanket cylinder and said impression cylinder for printing of the copy sheets; a sheet counter activated by said first timer substantially simultaneously with initiation of copy sheet feeding, and operable to count the printed copy sheets and, as a function of the sheets counted, to terminate inking of the master plate, transfer of the ink image to the blanket cylinder, and feeding of the copy sheets; a second mechanical timer operable when actuated by said operator, to initiate cleaning of said blanket cylinder and, after a presettable time interval, to terminate such cleaning; respective first and second timer actuators, for said first and second mechanical timers, coupled to said timer operator for conjoint operation thereby; coupling means operatively associated with both said first and second timer actuator and operable, when activated, to displace said second timer actuator out of operative relation with said second timer and to displace said first timer actuator into operative relation with said first timer; said coupling means, when deactivated, displacing said first timer actuator out of operative relation with said first timer and engaging said second timer actuator with said second timer; a selectively operable start control operable to activate said coupling means to couple said first timer to said timer operator through said first timer actuator; and means controlled by said counter and operable simultaneously with termination of feeding of the copy sheets, to deactivate said coupling means to couple said second mechanical timer to said timer operator through said second timer actuator.

Claim 3

An automatic offset printing press, as claimed in claim 1, in which said coupling means couples said timer to said timer operator through the respective timer actuators only alternately in such a manner that only one timer is coupled to said timer operator at any one time.

Claim 4

An automatic offset printing press, as claimed in claim 1, including transfer means operable to transfer the ink image from a master plate on said master cylinder to said blanket cylinder; and copy sheet feeding means operable to feed copy sheets singly and successively to said impression cylinder; each of said first and second timers including a cam rotatable in accordance with rotation of said blanket cylinder; and respective switch means sequentially operated by each cam; the cam of said first timer operating switch means controlling initiation of activation of said inking means, initiation of activation of said transfer means and initiation of activation of said copy sheet feeding means; the cam of said second timer controlling switch means initiating activation of said cleaning means and termination of activation of said cleaning means.

Claim 5

An automatic offset printing press, as claimed in claim 1, including a frame mounting the components of said printing press; said inking means comprising an inking unit insertable into said frame as a unit and releasably resting on cross members of said frame.

Claim 6

An automatic offset printing press, as claimed in claim 1, including respective manual means, operable independently of Said timers, to initiate copy sheet feeding and cleaning of said blanket cylinder, respectively.

Claim 7

An automatic offset printing press, as claimed in claim 1, in which timer operator is operable by said blanket cylinder once during each revolution of said blanket cylinder.

Claim 8

An automatic offset printing press, as claimed in claim 6, including a cam rotatable with said blanket cylinder; said timer operator comprising a cam follower engaged with said cam and oscillated once during each revolution of said blanket cylinder; said coupling means being electrically operable said coupling means, when deenergized, coupling said timer operator to said second timer; said start control comprising a switch selectively operable to energize said coupling means to uncouple said timer operator from said second timer and to couple said timer operator to said first timer; said counter, upon termination of said copy sheet feeding, deenergizing said coupling means.

Claim 9

An automatic offset printing press, as claimed in claim 1, including transfer means operable, when activated, to transfer the ink image of a master plate to said blanket cylinder; and copy sheet feeding means operable, when activated, to feed copy sheets singly and successively to said impression cylinder; said first timer controlling initiation of operation of said inking means, said transfer means and said copy sheet feeding means; said counter controlling deactivation of said inking means, deactivation of said transfer means, and deactivation of said feeding means; said second timer controlling activation of said cleaning means and deactivation thereof. 9 An automatic offset printing press, as claimed in claim 8, including respective solenoids controlling activation and deactivation of said means controlled by said first and second timers and said counter; and respective switches operatively associated with said solenoids and operable by said first and second timers and said counter.

Claim 10

An automatic offset printing press, as claimed in claim 8, in which said counter is operable to store the number of copy sheets to be printed; said counter decreasing the stored number by one responsive to each feeding of a copy sheet to said impression cylinder, and terminating operation of said sheet feeding means when the stored count reaches zero.

Claim 11

An automatic offset printing press, as claimed in claim 10, in which said counter deactivates said transfer means when the number of copy sheets to be printed has been reduced to a preselected relatively small number.

Claim 12

An automatic offset printing press comprising, in combination, a master cylinder for supporting a master plate; an inking means for the master plate; a blanket cylinder to receive an ink image transferred from a plate on said master cylinder; a cleaning means for said blanket cylinder; an impression cylinder operable to press copy sheets against said blanket cylinder; means operable to rotate said cylinders in respective directions; a timer operator operable by rotation of one of said cylinders; a first mechanical timer operable to initiate, in a timed sequence, inking of the master plate, transfer of the ink image to said blanket cylinder, and feeding of the copy sheets between said blanket cylinder and said impression cylinder for printing of the copy sheets; a start control selectively operable to couple said first timer to said timer operator; a counter activated by said first timer substantially simultaneously with initiation of copy sheet feeding, and operable to count the printed copy sheets and, as a function of the sheets counted, to terminate inking of the master plate, transfer of the ink image to the blanket cylinder, and feeding of the copy sheets; a second mechanical timer coupled to said timer operator by said counter substantially simultaneously with termination of feeding of the copy sheets, said second mechanical timer, when activated, being operable to initiate cleaning of said blanket cylinder and, after a presettable time interVal, to terminate such cleaning; transfer means operable to transfer the ink image from a master plate on said master cylinder to said blanket cylinder; copy sheet feeding means operable to feed copy sheets singly and successively to said impression cylinder; each of said first and second timers including a cam rotatable in accordance with rotation of said blanket cylinder; and respective switch means sequentially operated by each cam; the cam of said first timer operating switch means controlling initiation of activation of said inking means, initiation of activation of said transfer means and initiation of activation of said copy sheet feeding means; the cam of said second timer controlling switch means initiating activation of said cleaning means and termination of activation of said cleaning means; said first timer includes a first ratchet fixed to rotate with the associated cam; said second timer including a second ratchet fixed to rotate with the associated cam; first pawl means operable to engage and step said first ratchet; second pawl means operable to engage and step said second ratchet; said timer operator including an oscillatable follower lever oscillated by said blanket cylinder once during each revolution of said blanket cylinder, and further including a pawl means actuating lever connected to said follower lever and oscillated thereby once during each revolution of said blanket cylinder; and change-over cam means operatively associated with said first and second pawl means and operable to render only one of said pawl means effective at any one time while rendering the other pawl means simultaneously ineffective.

Claim 13

An automatic offset printing press comprising, in combination, a master cylinder for supporting a master plate; an inking means for the master plate; a blanket cylinder to receive an ink image transferred from a plate on said master cylinder; a cleaning means for said blanket cylinder; an impression cylinder operable to press copy sheets against said blanket cylinder; means operable to rotate said cylinders in respective directions; a timer operator operable by rotation of one of said cylinders; a first mechanical timer operable to initiate, in a timed sequence, inking of the master plate, transfer of the ink image to said blanket cylinder, and feeding of the copy sheets between said blanket cylinder and said impression cylinder for printing of the copy sheets; a start control selectively operable to couple said first timer to said timer operator; a counter activated by said first timer substantially simultaneously with initiation of copy sheet feeding, and operable to count the printed copy sheets and, as a function of the sheets counted, to terminate inking of the master plate, transfer of the ink image to the blanket cylinder, and feeding of the copy sheets; a second mechanical timer coupled to said timer operator by said counter substantially simultaneously with termination of feeding of the copy sheets, said second mechanical timer, when activated, being operable to initiate cleaning of said blanket cylinder and, after a presettable time interVal, to terminate such cleaning; transfer means operable to transfer the ink image from a master plate on said master cylinder to said blanket cylinder; copy sheet feeding means operable to feed copy sheets singly and successively to said impression cylinder; each of said first and second timers including a cam rotatable in accordance with rotation of said blanket cylinder; and respective switch means sequentially operated by each cam; the cam of said first timer operating switch means controlling initiation of activation of said inking means, initiation of activation of said transfer means and initiation of activation of said copy sheet feeding means; the cam of said second timer controlling switch means initiating activation of said cleaning means and termination of activation of said cleaning means; said first timer includes a first ratchet fixed to rotate with the associated cam; said second timer including a second ratchet fixed to rotate with the associated cam; first pawl means operable to engage and step said first ratchet; second pawl means operable to engage and step said second ratchet; said timer operator including an oscillatable follower lever oscillated by said blanket cylinder once during each revolution of said blanket cylinder, and further including a pawl means actuating lever connected to said follower lever and oscillated thereby once during each revolution of said blanket cylinder; and change-over cam means operatively associated with said first and second pawl means and operable to render only one of said pawl means effective at any one time while rendering the other pawl means simultaneously ineffective.

Claim 14

An automatic offset printing press, as claimed in claim 12, in which each of said first and second pawl means includes a respective ratchet advancing pawl engageable with teeth on the associated ratchet; each of said first and second ratchets having a toothless peripheral portion engaged by the associated ratchet advancing pawl when the respective timer has completed its switch means operating functions for idling motion of the respective ratchet advancing pawls.

Claim 15

An automatic offset printing press, as claimed in claim 13, in which each of said first and second pawl means includes a respective locking pawl preventing reverse rotation of the associated ratchet; and respective spring means operatively associated with each of said first and second ratchets and biasing the associated ratchet to return to a start position; each said spring being operative upon disengagement of the associated pawl means from the associated ratchet.