US2942543A - Series drive for web fed rotary printing machine - Google Patents

Description

June 28, 1960 J. G. Mc| v ETAL 2,942,543

SERIES DRIVE FOR WEB FED'ROTARY PRINTING MACHINE Filed Jan. 25, 1957 mvzm'rons: GEORGE J. WOLFER JOHN G. MILVAIN WW ATTYS- United States Patent SERIES DRIVE FOR WEB FED ROTARY PRINTING MACHINEv Filed Jan. 25,1957, Ser. No. 636,429 2 Claims. 01. 101-181) This invention relates to an improvement in web-fed printing presses wherein registering impressions are made on the travelling web in a plurality of different impres sion stations by a succession of printing couples consisting of sets of printing and impression cylinders located respectively at said stations. The invention relates more particularly to printing machines of the aforesaid type wherein the web in efifect, is driven or traversed by the several printing couples. a

In presses of the stated type there issome diificulty in maintaining the required absolute registration of the multiple impressions which jointly compose the finished matter, particularly after material wear has developed in the transmission mechanisms connecting the cylinders to the prime mover. Any slight difference in effective roll dimensions, or variables in the physical properties of the web, may cause the Web to be placed under abnormal tension between adjoining sets of cylinders or couples and will tend to cause the web to accelerate the rotation of the trailing set and to thereby overrun its transmission to an extent permitted by the backlash or play developed by wear in the latter. The resulting relative angular displacement of the cylinders at the adjoining stations means loss of registration in the impressions.

A principal object of the present invention is to provide a transmission system for presses of this class having inherent compensation for the aforesaid adverse effects of wear in the transmission elements.

Another and subsidiary object is to provide a transmission wherein precision machining of the elements to avoid backlash is unnecessary.

The invention will be more readily understood by reference to the attached drawings wherein:

Fig. l is a diagrammatic side elevational view of a printing press including transmission means for the several printing cylinders made in accordance with the principle of the invention;

Fig. 2 is a fragmentary plan view showing details of the transmission mechanism, and

Fig. 3 is a plan view similar to that of Fig. 2 showing 'a modified form of transmission within the scope of the invention.

With reference to the drawings, the printing rolls of the press therein diagrammatically illustrated are indicated respectively by the reference numerals 1, 2, 3 and 4; and the associated impression rolls by the numerals 5, 6, 7 and 8. These sets of rolls constitute in elfect four individual printing couples and are adapted to make their respective impressions in predetermined relatively aligned relation on the continuously travelling web 9 fed from a source not shown. The directions of web traverse and cylinder rotation are indicated by arrows. Intermediate the printing couples and the printing stations A, B, C and D which they respectively represent, the web is supported and guided by idler rolls as illustrated and readily understood by those familiar with the art. Conventional means is provided at 10 for starting the web 2,942,543 Patented June 28, 1960 2 under tension; and the usual compensators 11 are provided as indicated for accurate registration of the web with the individual printing rolls 2, 3 and 4. v I

The cylinders 1, 2, 3 and 4 are driven from a common motor 12. In the present instance the motor is connected to the cylinder 1 at the infeed end of the press by way of a shaft 13, a bevel pinion '14 at the end of the shaft 13, and a bevel gear 15 on the cylinder shaft or mandrel 16. As best shown in Fig. 2, the gear 15 meshes also with a pinion 18 on a shaft 19, and this shaft carries a pinion 20 at its opposite end which meshes with a bevel gear 21 on the shaft or mandrel 22 of cylinder 2. The gear 21, meshes also with a bevel gear 23 on a shaft 24 which carries a pinion 25 at its opposite end, this pinion meshing with a bevel gear 26 on the shaft'or mandrel 27 of cylinder 3. The gear 26 is connected through pinion 28, shaft 29 and pinion 30 with a bevel gear 31 on the shaft or mandrel 32 of cylinder 4. This transmission system is such that the cylinders are driven in series one from the other and all in the same direction as indicated. The use of spiral bevels is preferred.

The web 9, as illustrated, passes between and is pinched by the printing roll and impression roll of each 'couple and is traversed through the press by the latter and in the direction indicated. Under these conditions the transmissionsystem described above functions inherently to maintain exact registration between the several couples,

and therefore between the impressions made by the several couples regardless of backlash developing in the gears. If, for example, by reason of some variation in web thickness or in other web property, or of some slight difference in efiective cylinder diameter, the web tends to tighten between any adjoining pair of the stations, there will be a tendency for the web to drive the cylinders in the respective trailing positions at a rate faster than that established by the prime mover. With a conventional drive, the presence of backlash in the transmission train would permit such increase in rate to the extent of the backlash with resulting loss in the original registered relation of the affected cylinders. In the present instance, however, assuming for purpose of illustration that the increased web tension occurs between stations A and B, the pull of the web on cylinder 1 will be transmitted directly and immediately through bevel gear 15 to pinion '18, and since these two elements are already in the relation of driver and driven respectively the said pull will be transmitted without loss of motion due to backlash to the shaft 19. This shaft is the driver for the cylinder 2 at station B so that again the thrust is transmitted directly and without lost motion to gear 21 of cylinder 2. The cylinders 1 and 2 are thus positively locked in a relatively fixed angular or mutually registered relation which cannot be affected by play in the gear elements, Since the same condition exists in the transmission elements connecting the cylinder 3 both with cylinder 2 and cylinder 4, all of the cylinders are simideveloping in the transmission elements as a result of wear and will remain constantly in the registered relation.

It will be noted also that the gear 31 of cylinder 4 is connected through a pinion 33, shaft 34, and pinion 35 with a bevel gear 36 on the shaft or mandrel of one of a pair of web feed rolls 37 and 38 through which the web passes after leavingthe cylinder 4. Since the driven roll 37 is of difierent diameter than the cylinder 4 a speed change unit 39 is inserted in the shaft 34 so as to give the rolls the peripheral speed required to maintain the web in the proper driving tension between the cylinder 4 and the rolls. Increase in the tension of this portion of the web tending to overdrive the cylinder 4 will be neutralized therefore in the manner described above.

There may be some modification without departure from the principle of the invention. Thus, compensators of the known planetary type may be used in place of the units 11, the planetary units being inserted in the shafts 19, 24 and :29 inrknownmanner. that case, since a reversal of *shaft drive is a'nherentin a simpleplanetary, the pinions associate'dwith the gears 21 and 3-1 will be placed inthe same relation to their respective gears as the pinions 14 'and :18 to the gear 15 and the ipinions 25 and 28 to thegear 26. A system such as that illustrated in Fig. 3 may be ru'sed to obtain the desired series drive. In this case, each of theshafts or " mandrels 16, 22, 27 and 32 has two bevel gears attached thereto, the respective pair's of gears being indicatedbythe reference numerals 40, 41, 42, 43; 44, 45, and 46, 47. Since .the gears of the respective pairs are sep'arate,.the 'm'andrels themselves are introduced into the series ftransmission. The functional principle remains unchanged.

We claim:

1. A printing press or the like for makingprinted impressions on a continuous web comprising a "plurality-of impression stations through which the web is (passed successively at a given press speed to receive a plurality' of relatively registered printed impressions, a "printing couple at each station for making said impressions comprising a printing cylinder and animpression cylinder, said impression cylinders operable to engage and force the web into driving relation with said printing cylinders, said web being of such thickness and having such tension that it tends to drive the nextrpreceding printing cylinder at higher than press speed, web feed means including at least one driven roll about which said web passes following the last of said plurality of impression stations to engage and pull the web away from said last impression station, a gear connected to each of said printing cylinders and driven roll, and drive mechanism in-' cluding positive transmissiotn m'eans extending between each pair of adjoining stations and said last impression station-and said drivenroll rand drivably engaged with each of said gearsto connect the printing cylinder at each said station in series driving relation to and with the printing cylinder at the :next adjacent station and to connect the pr inting-cylindenat the last impression station to and with said driven roll.

2. Apparatus in accordance with claim 1 wherein said transmission means comprises a shaft extending between each pair of adjoining stations and said last impression station and said driven roll, said shafts each having at their opposite ends gear elements engaged respectively withthe gears of the proximate'printing cylinders and the ge'arof'said driven roll.

References Cited in the file of this patent UNITED STATES PATENTS 633,967 Smith Sept. 26, 1899 679,453 Carlson July 30, 1901 1,138,782 Pancoast May 11, 1915 1,223,347 Stoddard Apr. 17, 1917 2,104,065 Zuckerman Jan. 4, 1938

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