US2353048A - Intaglio plate printing machine - Google Patents

Description

July 4, 1944. v. LAROC CA INTAGLIO PLATE PRINTING MACHINE Filed Oct. 17, 1941 INVENTOR' Vtnceni Lanrcaz.

9 I ATTRNEY Patented July 4, 1944 INTAGLIO' PLATE PRINTING MACHINE Vincent Larocca, Brooklyn, N. Y., assignor to R. Hoe & 00., Inc., New York, N. Y., a corpora tion of New York Application October 17, 1941, Serial No. 415,365

6 Claims.

This invention relates to machines used in printing from flat engraved plates and which are commonly known as power plate presses. In this class of machines, the engraved plates are supported on beds, generally called planks, which are moved about a rectangular frame in a closed path on ways formed in or secured to the frame, the planks carrying the plates being passed successively under inking mechanism and wiping mechanism and then under an impression cylinder or roller. The planks follow a straight path along each side of the frame and make a turn at eachcorner. They are usuall connected to a fi'exible driving member, such as a chain that is supported by sprockets at each of the four corners of the frame, one of the sprockets being driven by an electric motor.

In Patent No, 2,223,369 issued December 3, 1940, a machine of the above class is shown, and the mechanism of the invention disclosed herein includes certain improvements over the machine disclosed in the specification of this prior patent, more particularly in the arrangement of certain details of construction wherein guiding members are provided, that are secured to the flexible driving member or chain, and engage guideways to steady and thus prevent undesired and excessive sidewise vibration of the flexible plank driving member.

From the foregoing, it will be seen that an object of this invention is to provide in power plate presses or the like, means to obviate undesired lateral vibration of a flexible driving member, such as a chain, while it is propelling a printing plate supporting bed or plank about a rectangular frame.

It is also an object of this invention to provide in a power plate printing machine or press, means to insure smooth and substantially quiet operation of a plank driving means which will be simple, durable and inexpensive in construction, as well as convenient, practical, serviceable and efiicient in its use.

With. the foregoing and other objects in View, that will appear as the description proceeds, the invention resides in the combination and arrangement of parts, and in the details of construction hereinafter described and claimed. it being understood that changes in the embodiment of the invention herein disclosed may be made within the scope of what is claimed without departing from the spirit of the invention.

A preferred embodiment of the invention is illustrated in the accompanying drawing, wherein:

Figure 1 is a top plan view showing a printing machine to which the features and principles of this invention are applied;

Figure 2 is an enlarged fragmental sectional view taken on the line 2--2 of Figure 1 and showing a preferred arrangement of the chain steadying means;

Figure 3 is an enlarged broken fragmental sectional view taken on the line 33 of Figure 1; and

Figure 4 is a further enlarged top plan view of the chain steadying means in operative position in a guideway.

The printing machine shown in Figure 1 includes a rectangular frame I I, having a rectangular opening at its center, and being provided with grooves or ways [2, l3 and I4, the ways [2 extending about the frame ll adjacent the periphery of the opening in the center, the ways 14 extending about the outer sides of frame II, and the ways l3 extending about the frame I l intermediate the ways 12 and I4. Supports I5 for printing plates, generally called planks and of which there are usually four, rest upon the frame H and are moved about the frame, and successively pasta sheet receiving station A, an impression roller mechanism IS, a delivery station E, a plate inking mechanism l1, and a plate wiping mechanism l8. Flat printing plates l9, carried by the planks l5, are thus each inked by the inking mechanism l1, wiped to remove excess ink by the wiping mechanism I 8, then may have a sheet placed thereon at A, and printed as it is passed under. the impression roller of the mechanism It, the sheet being removed, when the plate reaches position B.

The plate supports or planks l5 are guided about the frame II by rollers 2| rotatably mounted at each corner of the planks, and rollers 22 at their centers. The rollers 2! are arranged to ride in the ways I2 and I4, while the rollers 22 ride in the intermediate way I3. The roller 22 of each plank l5 has its roller shaft 23 secured preferably to an endless chain 24 by a plate 25 to which the shaft is secured and which is connected to the chain 24 by suitable link pins 26. The chain 24 is supported by and led around rotatable sprockets '21, one of which is disposed at each corner of the frame H. An electric motor 28, preferably of the type having a speed reduction gearing directlyassociated with it, is arranged to rotate one of the sprockets 2'! through a worm 29 and worm gear 3!, which latter is suitably 'secured to the sprocket 21. The chain engaging portion 32 (Figure 2) of the sprockets 2! is in alignment with channels 33 through which the chain 24 is fed. The channels 33 are below the planks l and in alignment with the way l3.

In machines of this kind, it is desirable that the curvature of the path of the planks where they turn at each corner of the frame be made with as small a radius as possible, so as not to reduce the length of the straight portion of the path, nor to increase the overall dimensions of the frame. In order to accomplish this, it is necessary to use relatively small diameter sprockets for the chain, and as a relatively heavy chain is required, the chain must be of a coarse pitch. This combination of a coarse pitch chain and a relatively small diameter, sprocket produces a condition which causes the straight stretches of the chain to move sidewise to a noticeable extent as each link of the chain passes a given point, the motion being perpendicular to a line tangent to the pitch circles of two successive sprockets and in the path of the chain. While this action is not objectionable at the speeds at which machines of this kind heretofore made are operated, it is found that with improved machines, such as that shown in the hereinbefore mentioned patent, when operating at the higher speeds for which they are designed, that the chain vibrates to such an extent that it affects the operation of the machine.

To obviate this disadvantage, rollers 34 are each secured to the chain 24 by being rotatably mounted on a stud 35 extending from a base plate 35, in turn fastened to the chain 24 by link pins 31. The rollers 34 are preferably positioned substantially midway on'the chain 24 between the rollers 22, and ride in the intermediate way I3 engaging its side walls 38 and 39, as do the rollers 22. These rollers hold the lengths of chain 24 between the sprockets 21, so as to effectively prevent sidewise vibratory motion. v

It will be seen that by means of the invention herein disclosed, means are provided for holding the straight stretches of the driving chain of a power plate printing machine, so as to confine it to its normal path, thereby preventing objectionable vibration and making it possible to operatethe machine at considerable increase in speed. p v v It will be'understood that the invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and it is therefore desired that the pres.-

as illustrative and not restrictive, reference being had to the claims rather than'to the foregoingdescription to indicate the scope of the invention.

What I claim is: a I I 1.. In a printing machine having a plate support arranged to carry-a printing plate, an endless flexible driving member; rotatable members positioned to support the driving member, guideways vertically aligned with the path of the driving member between the rotatable members, means connecting'the support with the driving member to move the support in a path following the guideways, carrying members secured to the driving member ahead of and behind the support, andguiding members on the carrying members ent embodiment be consideredv in all respects and engaging the guideways to prevent excessive vibration of the flexible driving member.

2. In a machine for printing from flat plates, a plate support, a frame having ways above which the plate support is moved in a horizontal rectangular path about the frame, an endless fiexible driving member, rotatable members for supporting the driving member below the ways, means connecting the platesupport to the driving member whereby the support will move in the path about the frame, and a carrying 'member spaced along the driving member from the plate support and arranged with a guiding member thereon to engage the ways to confine the driving member to a path in vertical alignment with the ways.

3. In a machine for printing from flat plates, a' frame having guideways arranged in a hori: zontal rectangular path in one plane, a flexible endless member disposed substantially in vertical alignment with the guideways and in another plane, means to drive the flexible member,- a plurality of plate supports secured to and spaced apart along the endless member, and guideway engaging members mounted on carrying members and secured to the endless member between the plate supports; the said guideway engaging members being arranged to engage the guideways to hold the endless member in alignment therewith. y

4. In a printing machine, a frame having a generally rectangular guideway arranged in a horizontal plane, a printing plate support on the frame, an endless chain secured to the plate support and led about the frame, sprocket wheels adapted to support the chain in a horizontal path parallel to and vertically spaced 'fromthe guideway, means to drive one of the sprocket wheels, and guiding rollers carried by means secured to the chain at positions spaced from the support and arranged to engage the guideway in the frame and prevent vibratory motion of the chain in the horizontal plane in which it is supported by the sprockets.

5. The combination in an intaglio plate print"- ing machine having a frame, plate supports movable horizontally about the frame, an end less chain connected to each of the plate sup ports and sprockets to support the chainin a horizontal plane beneath the plate supports, of a guideway in vertical alignment with the chain and in a horizontal plane vertically displaced from the chain, a carrying member secured to the chain between each two plate supports, and a guiding member on each carrying member and engaging the guideway to prevent vibration of the chain.

6. The combination in an intaglio plate printing machine having a frame, plate supports movable horizontally about the frame, an endless chain connected to'each plate support and sprockets to'support the chain in a horizontal plane beneath the plate supports, of a guideway, a first rollerrotatably mounted on a member secured to the chain at each plate support and a second roller rotatably mounted on a member secured to the chain between each two plate supports, the said first and second rollers en" gaging the guideway to respectively guide the plate supports, and prevent vibration of the chain.

VINCENT LA OCCA.

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