US3063369A - Rotary printing machines - Google Patents

Description

Nov. 13, 1962 E. A. TIMSON ROTARY PRINTING MACHINES 2 Sheets-Sheet 1 Filed July 6, 1959 INVE/VWK ERNEST ARTHUR 'rmsou Nov. 13, 1962 E. A. TIMSON 5 ROTARY PRINTING MACHINES Filed July 6, 1959 2 Sheets-Sheet 2 &

//V VE/V 7'01? 1 Ems'r ARTHUR 'rmsou BY T 7 I47'TOR/VE) United States Patent Ofitice 3,953,369 Patented Nov. 13., 1962 3,063,369 RUTARY PRINTING MACHINE Ernest Arthur Tirnson, 75 Northampton Road, Kettering, England Filed .iuiy e, @359, Ser. No. 32$,hh'7 Claims priority, application Great Britain July 11, 1958 3 Claims. (Cl. 101-247) This invention appertains to rotary printing machines of the kind adapted to print upon a web of relatively thin and flexible material such as paper, film, foil, or the like and comprising co-operable rotary printing units between which the travelling web passes to be printed upon and a drying Zone incorporating heating devices and through which the web travels after having been printed upon.

Thus, a machine of this kind is suitable for printing upon a web with volatile ink or like medium, the purpose of the drying chamber in this instance being to expedite evaporation of the solvent in the medium.

Rapid drying of inks is, for example, essential in a case where a web is to be printed upon in more than one colour, it is all the more necessary when such web is to be printed upon in more than one colour on both sides thereof.

Although there is no limitation in this respect the invention is primarily applicable to such a rotary printing machine wherein the drying chamber is fitted with fluid fuel, e.g. gas or oil, burners each of the form comprising a pipe or manifold into Which combustible fluid fuel from a supply is introduced and through which the said fuel passes to burner nozzles spaced along it. Thus, when the fluid fuel in such a burneris ignited, flame jets issue through the nozzles and, with the burner alight and fully operative these jets are directed towards an opposed surface of the travelling web.

Now, as previously mentioned, solvent in ink, during expedited drying by heating devices, rapidly evaporates. This rapid evaporation results in the production adjacent to the travelling web of a combustible mixture which ignites and burns without, however, overheating or scorching the web providing the latter is running at its normal full speed or thereabouts.

But if, in the event of the machine either stopping at the will of an attendant or being automatically brought to a stop in an emergency, such as a power failure, the web continues to be printed upon as the speed of the machine slackens during the stoppage, then the residual ignited combustible mixture of solvent and air would burn the printed web and cause it to catch fire, notwithstanding the fact that the heating devices had been turned or switched off.

The object of the present invention is to guard against this eventuality by the provision, in a rotary printing machine of the kind herein referred to, of simple and efficient means for automatically bringing about a cessation of printing during slowing down of the machine to a stop, with the result hereinafter to be described.

According to this invention, means influenced by the speed of the improved rotary printing machine, and hence functioning in accordance with the linear speed of the travelling web, are so interlinked with mechanism for bringing about a cessation of printing on the Web that the said mechanism is automatically actuated to bring about such a cessation at a predetermined speed of the machine during a stoppage thereof.

It is primarily the intention that a cessation of printing shall be brought about by effecting separation of the cooperable printing units. Alternatively, however, the same result could be achieved by blocking the ink feed to the forme on the appropriate unit. Or a combination of such measures may be adopted.

It is to be understood that either immediately prior to,

or simultaneously with, bringing about a cessation of printing, e.g. by the separation of the printing units, during a stoppage of the machine, the heating devices will be automatically rendered inoperative. For instance, in the case of fluid fuel, e.g. gas, burners associated fluid fuel valves will be automatically closed to cut off the supply of fuel to the burners at a predetermined speed during a stoppage.

The idea of the invention accordingly is that as the machine and the running web slow down during a stop and the heating devices are, as a consequence, turned or switched off, the printing shall also cease so that the web then passing through the drying chamber will be blank and devoid of ink. In these circumstances, there is no combustible mixture of solvent and air to burn and, therefore, no flame to fire the web which latter comes safely to a stop.

in a rotary printing machine including at least one rotary plate cylinder co-operable with one or more impression cylinders, the aforementioned means influenced by the speed of the machine may advantageously be interlinked with one or more conventional impression cylin der throw-off mechanisms.

In order that the invention may be more clearly understood and readily carried into practical effect, a specific example thereof will now be described with reference to the accompanying purely diagrammatic drawings, where- 1n,

FIGURE 1 is a diagram of a rotary printing machine of the kind concerned provided with means for automatically throwing an impression cylinder off a plate cylinder during slowing down of the machine to a stop, the cylinders being shown in the on position in this figure, and

FIGURE 2 is a similar diagram with the impression cylinder thrown-oil.

In the drawings, the numeral 1 indicates a rotary plate or design cylinder which is arranged to co-operate with an impression cylinder 2 at a printing station P in the machine. In FIGURE 1 a Web W of paper or the like to be printed upon is shown being drawn from a reel R through the station P and also through a drying chamber 3 incorporating web-heating fluid fuel, e.g. gas, burners, such as 4 and 5 controlled respectively by two solenoidoperated valves.

For drawing the web W through the printing station P and the drying chamber 3 there is provided an electric motor 6. Drive connections from this motor to the plate cylinder 1 are diagrammatically illustrated at '7, 8, 9 and 10.

The plate cylinder 1 is mounted in stationary bearings, and the impression cylinder 2 is adapted to be thrown on and off the said cylinder 1 by suitable actuation of a throw-off mechanism indicated generally at 11. This mechanism includes eccentric bearings 12. for the shaft 13 of the impression cylinder 2, and connected arms 14 for turning these bearings.

At 15 is represented the brush gear or other speed control mechanism of the electric motor 6 and, as will be seen, a process timer 16 synchronised with the mechanism 15 is employed to initiate and time the actuation of linkage whereby the throw-ofl mechanism 11 is operated and the solenoid-operated valves associated with the gas burners 4, 5 are controlled, at the appropriate time to bring about a cessation of printing upon the still travelling web W by throwing the impression cylinder 2 ofi the cylinder 1.

The timer 16 is incorporated in an electrical circuit L1, L2 and comprises a shaft 17 driven from the mechanism 15 and upon which is rigidly secured a rotary cam 18 for operating and controlling a switch 1'? whereby the circuit is opened and closed. The said electrical circuit includes the said solenoids for controlling the valves associated with the burners 4 and 5 and a solenoid arranged to influence an air valve 21 which, when suitably actuated at the dictates of the timer 16, passes air into the cylinder of a pneumatic cylinder and piston device 22, 23 arranged to impart motion to the arms 14 serving to operate the throw-01f mechanism.

Alternatively, hydraulically or electrically operated means may be provided to actuate the throw-ofi operating linkages under the control of a timing mechanism influenced by the speed of the machine.

Whenever the machine is started up, the initially separated co-operable rotary printing cylinders 1 and 2 will not be thrown-on to commence printing and the burners 4 and 5 will not be brought into operation until the machine and the web W have attained a speed at which it is safe to apply the heat, e.g. the same speed at which the said cylinders are automatically thrown-01f during stopping of the machine.

The complete arrangement illustrated in the drawings includes an inking unit 24 which is movable bodily towards and away from the cylinder 1, and means inter linked with the control for the throw-ofl? mechanism 11 whereby whenever the impression cylinder 2 is thrown off the cylinder 1 during a slow down of the machine, the inker unit 24 will also be automatically moved back clear of the cylinder 1. Conversely, the arrangement is also such that, during a start, the impression cylinder 2 will be thrown on to the plate or design cylinder 1 (at a predetermined linear speed of the web W) simultaneously with a forward movement of the inking unit into its working station adjacent to the cylinder 1. Although this particular feature is separately covered in co-pending United States application No. 827,613 and accordingly forms no part of the present invention, nevertheless it will be useful to observe that the same electrical circuit L1, L2 previously described herein and represented in the drawings includes another solenoid influenced air valve 25 which, through the medium of a pneumatic cylinder and piston device 26, 27 operates connections 28, 29, 30 and 31 (which it is unnecessary to describe in detail in the present case) for moving the inking unit 24 back and forth.

I claim:

1. A rotary printing machine comprising in combination plate and impression cylinders for printing on a traveling web, said cylinders being mounted for selective movement to and away from a cooperative printing engagement, driving means for feeding a traveling web through said printing cylinders, throw-01f means for moving said plate and impression cylinders selectively to and away from their cooperative printing engagement, synchronous means controlled by the speed of said driving means and cooperatively controlling said throw-ofif means for automatically shifting said cylinders away from said cooperative engagement when the driving means feeds the web at a speed less than predetermined speed and for automatically shifting the cylinders into said printing engagment when the driving means feeds the web at a speed at least as great as said predetermined speed, heating means for drying the printed web after the web is fed from said cylinders, and means actuated by said synchronous means and controlling said heating means for selectively applying heat to the web when the cylinders are in printing engagement and shutting off the heat when the cylinders are shifted away from said printing engagement.

2. The rotary printing machine of claim 1 in which said throw-off means comprises eccentric cam means for shifting one of said printing cylinders into and away from printing engagement with another printing cylinder, pneumatic control means for operating said cam means, and a solenoid controlled valve operating said pneumatic means.

3. The rotary printing machine of claim 2 in which said driving means comprises electrically driven motor means and drive connections from the motor means to one of said printing cylinders, and said synchronous means comprises a speed actuated electrical switch operated by said motor means and electrically connected to operate said solenoid control valve.

References Cited in the file of this patent UNITED STATES PATENTS 1,338,071 Cohen Apr. 27, 1920 1,668,154 Kelly May 1, 1928 1,723,878 Molins Aug. 6, 1929 2,003,799 Barber June 4, 1935 2,288,129 Feldhauser June 30, 1942 2,459,922 Crafts Jan. 25, 1949 2,682,218 Baumgartner June 29, 1954 2,818,804 Harless Jan. 7, 1958

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