US2215389A

US2215389A - Device for spraying printed sheets

Info

Publication number: US2215389A
Application number: US147326A
Authority: US
Inventors: Buttner Artur
Original assignee: Schnellpressenfabrik AG
Current assignee: Heidelberger Druckmaschinen AG
Priority date: 1937-05-05
Filing date: 1937-06-09
Publication date: 1940-09-17
Anticipated expiration: 1957-09-17

Description

A. BUTTNER DEVICE FOR SPRAYING PRINTED snma'rs 3 Sheets-Sheet 1 Filed June 9, 1937 N SW Sapt. 17, 1940. A. BUTTNER DEVICE FOR'SPRAYING PRINTED SHEETS Filed June 9, 1937 3 Sheets-Sheet 2 A. BUTTNER DEVICE FOR S'PRAYING PRINTED snma'rs Filed June 9, 1937 s Sihee ts- Sheet b vices for the purpose statedsuffer is that when the printing press is stopped while the spraying,

Patented Sept. 17, 1940 UNITED STATES PATENT. OFFICE DEVICE FOR SPRAYING PRINTED SHEETS Artur Biittner, Heidelberg, Germany, assignor to Schnellpressenfabrik Aktiengesellschaft Heidelberg, Heidelberg, Germany Application June 9, 1937, Serial No. 147,326

In Germany May 5, 1937 l 9 Claims. (01.91 453 ated either electrically or mechanically are required to determine the proper moment when.

the onset-preventing agent is to be applied to the sheets by means or the compressed air.

Those known plants are very expensive as regards their price-cost and their maintenance,

and in the practical employment the operator at- Y tending to the printing press and" to the said device must take care to adiustce'rtain members correctly, in that otherwise tlie-proper. operations, such as, for instance, the-complete atomisation of the liqliidagent, will'be disturbed. Assumed, this agent forms drops upon. the sheets,

every subsequent sheet will sticlrto the preceding one and these sheets which then'adhere to one another give rise to disturbances in the proper operationof the printing press.

Another drawback .from which the known dedevice is just in operation this device is not likewise stopped, but continues to operateuntil the attendant interrupts manually the further supply of compressed air to the spraying device. There is then between that stopping and that interruption a too thick layer of the onset-preventing agent applied onto the sheet Just having been printed which entails likewise the danger of sticking and, in consequence thereof, of disturbances.

The above-mentioned drawbacks of the known devices for the purpose stated are done away with by the present invention, the gist of which consists therein that individual successive amounts of compressed air are produced in successive periods of time corresponding with the succession in which the freshly printed sheets leave the printing press. Owing hereto, an individual predetermined amount of the compressed air is provided for every individual sheet, so that even if the printing press is stopped and the spraying device is not likewise stopped no further amount of the compressed air can get toethe sheet just having been printed so that also no further amount of the offset-preventing agent can find access thereto; Only a previously determined amount of this agent is delivered onto the last sheet. 1

The arrangement and combination of the'parts required for carrying out the just mentioned method ofloperation comprises first a spraying device for the ofiset-preventing agent and a compressed-air pump with which said device is connected without, the insertion of 'avalve there between; the said device is so designed that it commences to operate automatically when a certain predetermined pressure of the air has been reached. Separate control devices from which the spraying device depends do not exist. The.

compressed air opens first a passage through which it can escape'from the spraying device-and only thereafter another passage ,is opened order to be carried away by the same. Owing to this construction of the spraying device there is no possibility to let first escape the. offset-preventing agent and then the compressed air.

The present improved device is by far cheaper than the old ones and its operation is perfectly automatic so that faults by improper attendance are obviated. The only adjustment necessary is that of the amount of the offset-preventing agent to be sprayed onto the individualsheets. There is provided at the spraying device an adjusting through which the offset-preventing agent canpass to and into the jet of the compressed air in device bearing scale-like marks and designations,

air can act upon the spraying device only when printing takes place, whereby is obviated, counter to the known arrangement, that the spraying device need be separately stopped when the printing press is running idle, and need be sep- 1' arately started when printing is started anew.

With the present improved arrangement the spraying device can operate only as long as the printing takes place.

The invention is illustrated diagrammatically and by way of example on the'accompanying drawings on which Figure '1 is a vertical longitudinal section through the complete arrangestroke when the pressprints one sheet.

ment and combination of the parts constituting in their entirety the invention. Figure 2 is a side-view of a cylinder printing press equipped with the invention, this figure being drawn to a considerablyreduced scale relatively to Fig. 1 and the parts shown in the righthand upper corner of Fig. 2 being the same as are shown in Fig. 1 in the considerably enlarged scale relatively to Fig. 2. Figure 3 is a side-view of a platen printing press provided with the invention, the scale being about the same as that of Fig. 2 and the parts shown in the left-hand portion of the upper half of Fig. 3 are the same as those shown in the left-hand half of Fig. 1;

The spraying device proper, also termed spraying gun, consists of the casing l3 which is at its lower end provided with the spraying nozzle 3. The liquid offset-preventing agent is contained in the receptacle 4 which is connected with said casing l3 by means of a tube I4. Between the casing and the nozzle is a conical member I6 having a central passage which is closed by means of an accurately fitting needle l5. Within the casing I 3 ma piston l8 through which the nozzle needle l5 extends upwardly. The piston is subjected to the pressure of a compression spring 2 I, the pressure of which can be regulated by an adjustable nut 22 in such a manner that the spring pressure corresponds with that air pressure. at whichthe spraying device is to commence to operate. Coaxially with the spring 2| is a likewise helical compression spring 20 which acts upor. the needle I5 by the intermediary of a collar l5 provided on the needle.

In the frame of theprinting press equipped with the spraying device is arranged a cylinder 5 in which a piston I0 is reciprocated by means of a connecting rod 9 moved by a crank-pin 8 projecting from a disk (or crank) I secured to to make use of 'a lever-transmission of such a construction that the piston l0 performs one The cylinder 5 sucks in the air through a valve 28, compresses it thereafter and presses the compressed air through a tube 6 and a bore 25 into the casing l3 of the spraying device which is tightened by means of a stuffing box 11. The

compressed air moves the piston i8 upwardly and opens thereby one end of a passage 26, the other end of which communicates with the air nozzles 21. Therefore, first only the compressed air will escape from said nozzles.

But when the piston 18, further being moved upwardly,'pushes upon the collar I9 of the nozzle needle l5, it takes this needle along with it wherespring 2| whereby also the further supply of the V air will be interrupted.

The movement of thenozzle needle with its collar in upward direction is limited by means of an adjustable eccentric disk 24 supported by an arm 23 projecting upwardly from the casing l3. On said disk are marks which for instance may be denoted light form, medium form, and "heavy form, and there is on the top of the arm 23 a pointer 24 relatively to which the disk 24, or its marks respectively, can be adjusted, so as thereby to determine the extent of the lift of the nozzle needle according to the requirement. Ifthe disk 24 is, for instance, adjusted for light form, only a correspondingly small amount of the liquid offset-preventing agent can be ejected and sprayed, whereas in the other two cases a correspondingly larger amount will be delivered.

The stroke and the diameter of the air-pump depend on the amount of air required for one printed sheet. That amount is from 0.5 to 2 liters for one sheet.

If the spraying device is not to be used, the compressed air can be let out into the atmosphere from the cylinder 5 through a cock I2 provided at the cover'l I of the cylinder.

The compressed air pump employed in the present case is a slowly-running pump, in consequence whereof only little lubricating oil .is needed and, therefore, an. oil separator can be dispensed with. The pressure-stroke of the pump piston is so timed with respect to the operation of the printing press that each of the successive amounts of air is compressed within that period of time in' which every individual printed sheet can be sprayed with the offset-preventing liquid. 1

In order to prevent actuating of the spraying printing couple disengaged, the following means are provided.

At the cover ll of the pump cylinder 5 is a branch 29 provided with a valve 29 which canbe turned by means of a lever 30. A spring 30 tends continually to keepsaid valve closed. The start ing and stopping lever of the printing press can act upon a push-bar 3| which when being shifted from the position I intotheposition II turns the lever 30 and opens thereby the valve 29 This takes place when the above-mentioned lever of the printing press has been turned into its position for disengaging the printing couple, so that the air subjected to the action of the piston 5 is not compressed but driven into the atmosphere through the open valve 29 When the spraying device is attached to a cylinder' printing press, as in Fig. 2, it is carried by a column 2 connected to the machine frame and it is (Fig. 2) supported in such a height that it is located above the delivery-pilel of the printing press. The pump 5 is driven by means of the crank shaft 1 of the driving gear for the composi tion bed. a

The freshly printed sheets are preferably sprayed just at that moment at which the sheets have arrived over the delivery-pile, i. e. prior to the sheets sliding from the delivery means of the printing press upon the pile.

33, Fig. 2, denotes the lever for interrupting and recontinuing the printing operation, for instance, by raising and lowering of the impression cylinder of the cylinder printing press. A

lever 32 is fixed to axle 34 of lever 33. This lever 32 is connected to the rod 3|, which is'operating, as already mentioned, the members 30 and 29 (Fig. 1).

If the invention is to be used in connection by a column Zby means of which the spraying device is attached to the press, the arrangement device when the printing press is running with the being again such that the spraying nozzle is located above the delivery-pile I. r v

9 denotes the oscillating platen which is connected .with the piston of the compressed-air pump 5 by means of a bolt 8 and a rod 9. The platen is supported on the axle 35 and is moved to and fro from the, main-shaft 31'by the intermediary of a toggle-lever 36.

The pump piston can, however, be moved from a so-called one-revolution shaft, whereby also consecutive compression-strokes of the air pump are obtained.

33 denotes the lever for interrupting and recontinuing theprinting operation. This lever is fixed to a shaft 34 to which is, furthermore, secured a lever 32, the free end of which abuts on a horizontally shiftable bar 3| subjected to the pull of a tensile spring 38 which holds the members 3| and 32 in contact with one another. The member 3| is an equivalent for the rod 3| of Fig. 1. This is true also of the lever 30 which is connected with the plug of a valve 29 When the lever 33 is in the position I shown in Fig. 3 the press is printing, but when it is downwardly turned so that the point I (the point of contact between the members 3| and 32) gets into the position II, the lever 32 is turned, the rod 3| shifted by the spring 38, the lever 30 likewise turned and the valve 29 opened by a spring (not shownin Fig. 3) so that the air contained in the pump cylinder escapes into the atmosphere in uncompressed state, all as has already been described with respect to Fig. l.

The moment of spraying can be determined at will if the driving power for the spraying device is derived from a one-revolution shaft. The most suited point of time is that at which the platen is in its printing portion, as in this position the composition bed and the inking rollers are least,

exposed to the atomised offset-preventing agent.

I claim: 1. A device for spraying an offset-preventing agent upon freshly printed sheets coming from a printing press, comprising, in combinatioma compressed-air pump, so connected up to the printing press as to produce successive amounts of compressed air of a predetermined pressure suited for the purpose in view in periods of time corresponding with the succession in which said sheets leave said press; a receptacle containing the offset-preventing agent to be sprayed; a spraying device, so designed as to be able to operate mechanically when the predetermined pressure has been attained; a valve-less conducting connection between said pump andsaid spraying device, and a connection between said receptacle and the said spraying device.

2. A spraying device as specified in claim 1, further comprising, in combination with the casing of said spraying device, two apertures, of which one communicates with the compressedair conduit and the other communicates with the conduit for the offset-preventing agent; means forming part of the spraying device and being so designed as to permit access of the compressed air to the spraying device and the formation of a jet of said air prior to permitting access of the offset-preventing agent into the jet of the compressed air.

3. A spraying device as specified in claim 1, further comprising, in combination with the easing of said spraying device, a spraying nozzle at so located relatively to the connection between said casing and the compressed-air pump as to be able to establish and interrupt said connection, substantially as set forth.

4. A spraying device as specified in claim 1, further comprising in combination with the casing of said device, a spraying nozzle at said casing, a shiftable needle passing through said nozzle, and adjusting means for the extent of motion of said needle, substantially as set forth.

5. A spraying device as specified in claim 1, further comprising, in combination with the cascasing, a shiftable needle passing through said nozzle, a piston arranged in said casing and adapted to actuate said needle valve, and a spring so arranged with respect to said piston as to act on it and to determine thereby the pressure effecting the opening of said nozzle by the said needle, substantially as set forth.

6. A device for spraying an offset-preventing agent upon the freshly printed sheets coming from a printing press comprising in combination, a receptacle containing the agent to be sprayed, spraying means arranged relatively to the arriving freshly printed sheet so as to be able to direct said agent onto the sheet,.lmeans for connecting said receptacle to said spraying means, a compressed air pump so dimensioned that it produces for each of the printed sheets to be sprayed only so much compressed air as is required for a single spraying operation, said compressed air pump being directly connected to the spraying means by a valve-less conducting connection and conveying the produced quantity of air to the spraying means.

7. A device for spraying an offset-preventing agent upon freshly printed sheets coming from a printing press comprising in combination, a

ing of said device, a spraying nozzle at said less conducting connection between said pump.

and said spraying device, and a connection between said receptacle and the spraying device, an exhaust valve on said compressed air pump, and means for operating said exhaust valve in such manner that the spraying device is actuated by the compressed air only when the press has been started for printing.

8. A device for spraying an offset-preventing agent upon freshly printed sheets coming from a printing press comprising in combination, a compressed-air pump so connected to the printing press as to produce successive amounts of compressed air of a predetermined pressure in periods of time corresponding with the succession in which said sheets leave said press; a receptacle containing the offset-preventing agent to be sprayed, a spraying device so designed as to be able to operate mechanically when the predetermining pressure has been attained, a valveless conducting connection between said pump and said spraying device, and a connection between said receptacle' and the spraying device, an outlet-valve provided on said compressed-air pump, and means for opening said valve when the printing operation is interrupted.

9. A device for spraying an offset-preventing agent upon freshly printed sheets coming from a printing press. comprising, in combination, a

the offset-preventing agent to be sprayed; a spraying device, so designed as to be able to operate mechanically when-the predetermined pressure has been attained; a. conduit between said pump and said spraying device, and a conduit between said receptacle and the said spraying device.