US1721408A - Compensating device - Google Patents

Description

July 16, 1929- .1. PERDRr-:AU 1,721,408

ooMPENsATING DEVICE Filed May 18, 1926 2 sheets-spew l July 15 1929 J. PERDREAU COMPENSATING" DEVICE Filed May 18. 1926 l2 sheefsfsheetv 2.

Patented l.lilly i6, l929.

mareas JEAN PERDREAU, OF PAR-IS, FIR-ANCE, ASSIGNGR T SOCETE ANONYME' MARINONI (FIAGHINES ET lJIATERIEL POUR LIMPRIMERIE ET LES INDUSTRIESANNEXES OF PARIS, FRANCE.

COMPENSATING DEVCE.

Application filed May 18, 1926, Serial No. 109,988, and in France April 30, 1926.

Printing machines of certain classes are in use in which th-e thickness of the operative part of the printing cylinder is variable within restricted limits.

For this reason, the diameter of the said cylinder will not be uniform, and it may be somewhat larger or smaller than the pitch circle of the gear wheel secured to the cylinder which it actuates. ln either' case, the result will be a certain friction of the printing cylinder upon the pressure cylinder which is in contact therewith, which is prejudicial to the printing work produced by the machine.`

In particular, in the rotary printing machines for sunken relief work, such as intaglio rotogravure, heliogravure or the like, the printing cylinders usually employed have the form of a steel core which is covered with a thin envelope of electrolytic copper, upon which the printing work is engraved. Then the printing operation is completed, the said envelope is treated by the polishing process, whereby the thickness of the engraved metal is removed.

ln this manner, each time the operative surface is renewed, the diameter of the cylinder will be reduced.

rl`his disadvantage has been obviated in practice by modifying the facing of the pressure cylinder for each change in the dialneter of the printing cylinder, but this is only a rough approximation, and it offers inconveniences as regards the. lineness of the printing.

Il`he present invention relates to a device which assures in an automatic manner, during the printing period, the. exact equality of the periphery speeds of the printing cylinder and the pressure cylinder', so that no change need be made in the diameter of the pressure cylinder and hence in the thickness of its facing.

rlhe following description with reference to the appended drawings which are given by way of exan'iple shows an embodiment of the said invention.

Fig. l is a diagrammatic view which relates to the independent con trol of the pressure cylinder and the printing cylinder of a rotary printing machine adapted for hollow relief work, and Fig. 2 is a. corresponding developed plan view.

Fig. 3 is a v4front view mechanism.

Fig. 4 is a section on the line lof Fig.

of the compensating Figs. l5', 6-7, 8 9, 10 are detail views of the mechanism on a smaller scale, respectively in front elevation and in section.

Fig. l1 is a diagram showing the opei'ation of t-he mechanism.

The printing machine ofthe sunken relief type for sheet work, provided with a pressure. cylinder, comprises as shown in "F a pressure cylinder D and a printing cylinder A having half the diameter of the former and rotating in Contact therewith. The pressure cylinder makes but one revolution while the printing cylinder makes two.

The pressure cylinder is driven from the Vflywheel .shaft through the medium of the gear wheel C which engages a gear wheel secured to the said pressure cylinder.

The rotation of the printing cylinder A is effected indirectly by the same wheel C, through the m-edium of the compensating device, the object of the present invention, which is shown diagrannnatically by the circle B in Fig. l. n p

In this manner there is no direct gear engagement between the pressure cylinder and the said printing cylinder.

The principle of the compensator, the object of the invention, is as follows:

It should be noted in the first place that in the machine herein employed, the printing takes place only during each alternate revolution of the printing cylinder.

In these conditions, the compensating apparatus will automatically assure a periphery speed for the printing cylinder whichv is equal to that of the pressure cylinder during the operative or printing revolution of the said printing cylinder. i

Should there be produced an angular displacement, to the front or rear, of the position of the cylinder relatively to the position which it would occupy if .its diameter were the same as that of the pitch. circle, and hence relatively to its driving wheel, during the second revolution of the printing cylinder, the said compensator will take up this difference, so that the printing cylinder will make two complete revolutions while they pressure cylinder'makes one revolution. l f

A constructional form of the said compensa-tor B is shown in Figs. 3 to 10.-

Upon the main frame 2 of the printing machine is mounted a short horizontal shaft l, it being secured for example by means of the nut 3 which is scr-ewed'to the threaded end lgs. ll and 2 y 1 of thc said shaft and presses the washer 3a against the frame 2.

The end 1" of the shaft 1 serves to support the said compensating device.

This latter comprises a stationary dise 4 which is mounted upon the part of the shaft 1b and is secured to the machine frame by the bolts 5; in the disc 4 is formed a slot constituting a cam 4a (Fig. 5) having a suitable outline, such as the one shown in Figs. 3 and 5.

In the said cam slot is movable a roller G disposed upon an axle 7, mounted in the plate 8 which is bored to a diameter larger than that of th-e shaft portion 1b. The said plate carries, diametrically opposite the roller G, a tenen 12 which is radially slidable in a guide slot llafformed in the gear wheel 11, which is loosely rotatable on the journal portion 1b. The gear wheel 11 receives a uniform movement of rotation from the main driving element of the machine, i. e. it is in gear engagement with the wheel C (Fig. 1).

The plate 8 carries, on the tenon 12, a sliding member 10 which cooperat-es withv the guides 13a formed in the recessed plate 13 which is secured to the second gear wheel 14, loose on the journal portion 1" and in gear engagement with the printing cylinder A (Fig. 1)'. rThe said parts are secured tou gether by means of a circular boss 19 formed upon the said plate, which is insert-ed into a corresponding recess or bore in the wheel 14, and also by the two nuts 15- (F ig. 3); however, as shown, in Fig. 3, the plate 13 is provided with two slots 1G which are centered upon the axis of the boss 19, so that the plate may be given an angular displacement relativ-ely to the wheel 14 about the said axis 19, whose value a on either side of the line A-A may be observed by means of the pointer 17 which is movable before a suitable graduated scale formed upon the front face of theiwheel 14. A knob 1S, mounted on the said plate, allows the latter to be seized for effecting the angular displacement of the plate. The proper position of the said plate having [irst been calculated, and then adjusted according to the indication of the pointer 17 and the graduated scale, as will be further disclosed, the nuts 15 are screwed down, and the plate 13 is then secured to the gear wheel 14.

The two wheels 11 and 14 which are mounted in the adjacent position upon the journalv 1b are maintained in place by the washer 20 which is mounted onthe end of the shaft and is held in position by the lubricating nut 21.

The operation of the apparatus is as follows:

The wheel 11 is actuated at a uniform speed ofrotation by the wheel C. By means of the tenon 12 it actuates the plate 8 whose other end-through the medium of the roller G--is guided by the face of the cam 41 of the stationary dise 4. The plate 8, when rotating,

nvenaos rotation of the wheel and the axis of the` tenen 12, will be periodically variable, the period being one revolution of the wheel 11.

The sliding member 10, which moves between the guides 13R, will draw the plate 13 with it in its rotation, and will participate in the radial sliding of the tenon 12 with which it is inline. In this manner the lever arm Z1 for the entraining of the said plate and of the wheel 14 which is connected therewith-which lever arm is represented by the distance between the axis l1/--j1/ of the boss 19 and the axis of the shaft 1-will vary at each instant. 1f it be supposed that the pla-te 13 is so n'iounted upon. the wheel 14 that its plane ot' symmetry shall pass through the axis of shaft 1 (position of Fig. 3) it will` be readily observed that the rotation of the wheel 14, actuated by the roller 10, will be uniform.

The whole action takes place as if the two gear wheels 11 and 14 were secured together. But if the plate 13 is given an angular displacement relatively to the wheel 14 by turning said plate through an angle a about its pivot boss 19, the guide 13 will no longer have the radial. direction (Fig. 11), so that the center ofy the slide 10 will be displaced, during a complete revolution of the actuating wheel 11, between two limiting positions D0 andl)1 considered with reference to the wheel 14. If one commences to turn the whole device trom the moment at which the roller G is at the point ola of the sloty 4a nearest the axis 1, the slide 10 will now have the positionl D0 (Fig. 11).

Then the wheel 11 has made half a revolution the printing cylinder A will now have made a complete revolution. At this time, the angular spacing of the toothed wheels 1 and 14 is amaximum.

rl`he slide actuating the wheel 14 has now attained the position corresponding to the point of the. slot 4a which is farthest from the axis 1. During the next revolution, the printing cylinder will not print. The appa.- ratus then returns to the initial point D0 in order to recommence the cycle whose period is represented by two revolutions of the printing cylinder A. 1t will be noted that between the positions D0 and D1 of the slide 10, two points on the wheels 11 and 14, which coincided at the beginning, will now be spaced apart by the quantity [Z0 Z1 which represents the difference between the pitch circle of the toothed wheel keyed to the shaft of the printing cylinder, and the exact circumference of the said printing cylinder.

Otherwise stated, during half a revolution of the wheel 11, which rotates at constant speed, the wheel 14 will also be rotated at a constant speed, but this will be higher than the speed of the wheel 11, so that the periphery speed o1 the printing cylinder A actuated by the wheel 14 will be exactly equal to the periphery speed of' the pressure cylinder D, but during the next halt-revolution, the wheel 14e will be driven at a reduced though constant speed, the differences (either way) between the speeds during the half-revolutions being exactly equal, so that the wheels 11 and 111 will be again in the same relative angular position at the end of a complete revolution of the wheel 11.

The value of this difference in speed is exactly given by the length (Z0 (Z1, and it depends upon the inclination or the angular displacement of' the plate 13 with reference to the wheel 1-1 about the pivot boss 19. It will be an easy matter to record opposite the pointer 17, on either side of the line 1 -1, the indications which will permit of giving to the plate 13, without repeated trials, the proper inclination depending upon the new disposition of the printing cylinder.

Obviously, the application of. the aforesaid compensating mechanism is not limited to a machine for printing in hollow relief as herein disclosed by way of example, but it may be utilized with all types of printing or like machines in which the rotating cylinders must be given a periphery speed which is periodicallyandmomentarily different from the speed of the pitch circle of the actuating` gear wheels to which they are secured.

that I claim is:

1. A compensating device for periphery speeds, comprising a first wheel which is actuated at constant speed, a second wheel having the same axis of rotation as the first, a cylinder mechanically connected with the second wheel and adapted to be actuated at variable speed, adjustable means for mechanically actnating the second wheel from the first wheel, said regulable means comprising a disc coacting with the first wheel, means to impart to the disc, in addition to a rotary movement, a movement of translation in its plane, means connected with the disc and adapted to drive the second wheel, means for driving the second wheel, adjustably connected with said second wheel and slidably engaging said disc, whereby slide movement oit the disc is converted into an additional rotation o'f last mentioned means and of the second wheel, for an amount which may be varied at will by adjusting said means upon the second wheel.

2. A compensating device for periphery speeds, comprising a first wheel which is actuated at constant speed, a second wheel havin the same axis of rotation as the first, a cylinder mechanically connected with the second wheel and adapted to be actuated at variable speed, a disk co-acting with. the first wheel, means for actuating the disk by the constant speed wheel and for imparting to said disk a movement of rotation and also a sliding movement in its own plane, the said disk resuming the same position after a revolution ot the wheel, a member having a slot formed therein which member may be connected with the second wheel, means for driving the second wheel by means of the disc, said means being connected with the disc and slidable in the said slot, and means 'for varying the inclination ot the said slot with reference to the radial direction on the second wheel, whereby the second wheel will be actuated during half a revolution at a greater speed than the first wheel by a quantity which is variable according to the inclination of' the said slot, whilst during the other haltof the revolution the speed of the second wheel will be less than that of the :first wheel by the same variable quantity.

3. A compensating device for periphery speeds, comprising a first wheel which is actuated at constant speed, a second wheel having the same axis of rotation as the first, a cylinder mechanically connected with the second wheel and adapted to be actuated at variable speed, a disk coacting with the first wheel, means for actuating the said disk by the constant-speed wheel and for imparting to said disk a movementrof rotation and also a sliding movement in its own plane, the said disk resuming the same position after a revolution oit the wheel, a plate which is applied against the second Wheel and comprises a vertical slot, means for displacing the said plate relatively to the second wheel whereby the said slot may be inclined from the radial direction, means .for driving the second Wheel by means of the dise, said means being connected with the said disk and adapted to slide in the said slot in the plate in such manner that the said plate will be rotated, means whereby the said plate may be connected with the second wheel in all angular positions of the plate, in such manner that the speed of the second wheel will be greater than that of the first wheel by a certain quantity during half a revolution and will be less than this speed by the same variable quantity during the other halt of the revolution.

fl. A compensating device for periphery speeds comprising a first wheel which is actuated at a constant speed, a second wheel having the same diameter and the same axis of rotation as the iirst, a third wheel actuating a cylinder of variable speed and in gear engagement with the second wheel, a stationary plate, having a groove formed therein, a roller movable in the said groove, a .rotatable and Slidable plate carrying the axle of the said roller, a tenon mounted upon the said plate in the diametrically opposite position with reference to the said roller, a slot 'formed in the first wheel and coacting with the said tenen, a slide carried by the said tenen, a

plate wherein the said slide is movable in a pair of guides, and adjustable means whereby the said plate is held in position against the secon d Wheel.

5. A compensating device for periphery speeds7 comprising a lirst Wheel which is aetuated at a constant speed, a second Wheel having the same diameter and the same aXis of rotation as the first, a third Wheel actuating a cylinder of variable speed and in gear engagement with the second Wheel, a stationary plate, a groove formed therein, a roller movable in the said groove, a rotatable and slidable plate carrying the axle of the said roller, a tenon mounted npon the said plate in the dian'ietrically opposite position'with reference to the said roller, slot formed in the first Wheel and coaeting With the said tenon, a slide carried by the said tenon, a plate wherein the said slide is movable in a pair of guides, an axle or journal secured to the said plate and enacting with a bore or recess :formed in the second wheel, means for the angular displacement ot the said plate relatively to the second Wheel by pivoting said plate upon the said journal, means for securing the said plate to the second Wheel in the proper position, and means for indicating the amount oitl the angular displacement.

In testimony whereof I have signed my name to this specification.

JEAN PERDREAU.

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