US2210500A - Mandrel for a printing plate - Google Patents

Description

Aug. 5, 1940. Q J ROHLAND 2,210,500

MANDREL A PRINTING PLATE Filed April 2, 1937 2 Sheets-Sheet l h 5 INVENTOR. 52 llzzfff/i o/awd A TTORNEYS.

Aug. 6, 1940. Q J RQ'HLAND 2,210,500

MANDREL FOR A PRINTING PLATE I Filed April 2, 1937 2 Sheets-Sheet 2 IN VEN TOR.

J zz/f f/ a/a/yd BY m A TTORNEYS.

Patented Aug. 6, 1940 UNITED STATES MANDREL FOR A PRINTING PLATE Curt J. Rohland, Seekonk, Mass., assignor to Paul-Rohland, 1110., a corporation of Rhode Island Application April 2, 1937, Serial No. 134,561

6 Claims. (01. 101- 378) ties in which plates of varying axial lengths may be secured thereto without a material change in the structure of the mandrel.

Another object of the invention is the provision of a printing mandrel which will accommodate plates of either complete cylindrical or hoop form or plates covering but a part of the arc of the m cylinder with arrangements such that the edges of the latter plate are bound to the mandrel firmly and securely Without a cramping or undue strain on the parts of the mandrel.

Another object of the invention is the pro- 20 vision of a mandrelwhich will accommodate a plate having either its ends abutting parallel to the axis of the mandrel or at an angle to the axis of the mandrel.

Another object of the invention is to provide a 25 mandrel in which the securing means comprise overhanging or undercut edges which will grip the plate and bind it in position.

Another object of the invention is the cushion ing of the printing plate for some forms of work 39 and yet hold the same securely in position.

Another object of the invention is to provide a bearer for the print plate which will substantially completely support the entire area of the print plate.

With these and other objects in view, the invention consists of certain novel features of construction, as will be more fully described, and particularly pointed out in the appended claims.

In the accompanying drawings: 40 Fig. 1 is a section view of an assembly of the printing cylinder with a plate strapped thereon; Fig. 2 is a sectional view of the body portion of the cylinder and the parts integral therewith; Fig. 3 is an elevational view of the spacer and 43 bearer member which is provided on the body;

Figfl is a section view of the movable binder member which is for engaging the opposite edge of the print plate; 1

Fig 5 is an elevational view of the nut for engaging the binder member;

Fig. 6 is a sectional view on line 6-6 of Fig. 1;

Fig. 7 is an end view of the spacer member shown in Fig. 3;

- Fig. 8 is an elevational view of the structure 55 shown in Fig. 1 in completely assembled position;

Fig. 9'is an end view showing the print plate of complete hoop or cylindrical formation as being positioned over the end of the cylinder;

Fig. 10 is a sectional View of a modified form of plate holder or mandrel; 6

Fig. 11 is a section on line llll of Fig. 10;

Fig. 12 is a section on line l2l2 of Fig. 10;

Fig. 13 is an elevational view of a still different modification showing the resilient means extending parallel to theaxis instead of circularly about 10 the axis of the printing plate holder or mandrel.

Very thin plates are sometimes strapped or screwed on mandrels or printing cylinders in use,

but this manner of securing them is not entirely satisfactory; and in order toimprove upon such structures I have provided a heavier steel plate which may be formed arcuate in accordance with my co-pending application, Serial No. 134,562, filed April 2, 1937; and which may be strapped upon the cylinder by engagement with the edges '20 of the plate with such an arrangement as to force the plate against the bearing surface of the cylinder, the plate being sufficiently heavy and well supported so that for practical purposes it becomes firmly fixed to the cylinder or a part thereof; and the following is a more detailed description of the present embodiment of this invention, illustrating the preferred means by which these advantageous results may be accomplished: i

With reference tothe drawings, the body portion of my printing cylinder or mandrel is designated Ill and consists of a cylindrical member, having a central bore H for mounting upon a shaft or the like. This cylindrical member has an integral flange I2 at one end which is undercut as at 13 providing aninclined surface M, as shown in Fig. 2, which converges toward the bearer surface [5 of the body of the mandrel; The opposite end of the mandrel is reduced as at i6 and is externally threaded as at IT.

A binder member I 8 has a bore it to fit upon this reduced portion and slide upon the outer surface 20 thereof. This binder member has a bearer surface 25 and a flange 22 undercut as at 23 with an inclined surface 24, which is a substantial duplicate of the flange with its undercut portion and inclined surface I2, l3 and Hi. There is also provided in this binder member a threaded opening 25 for the reception of a threaded pin 26 which may be rotated by reason of the slotted end 21 to extend different amounts and bear against the face 28 of the body so that this portion of the binder member may be supported when its diametrically opposite portion binds used.

against a plate covering but a portion of the arc of the circle and thus no cramping action or tilting of the member 18 will occur with reference to the reduced portion l6.

This binder member is urged toward the body it by a nut 29 which has a threaded bore St to threadingly engage the threads I? of the body. The outer surface of this nut 3! is knurled so as to afford a good gripping surface for the hand of the operator for manipulation of this nut.

A spacer and bearer member 32 having a bore 33 is received by the boss 35 on the binder member 18 which centralizes it with reference to the body of the mandrel and the binder member and provides a support by means of its bearing surfaces 35 for the plate which is to be engaged. Varying lengths of plates will require spacers 32 of different axial dimensions which may be substituted in the printing cylinder to effect proper spacing with reference to the length of the plate In use, a plate such as 31 is provided with inclined edges 38 which correspond approximately with the angle of incline of the surfaces i and 24. This plate, if of a length such as shown in Fig.1, with reference to the body, will have the spacer 32 provided between the binder member i8 and the face 28 of the body. The plate 3'! in this instance, here shown, covers an arc of approximately one-half of a circle (see Fig. 6).

Accordingly, the threaded member 26 will be turned down sufficiently so that it will provide a support for the diametrically opposite portion of the binder member so that when the nut 29 is turned up to force the binder member toward the body so that its undercut edge will engage the edge 38 of the plate it will be supported at diametrically opposite points and be moved inwardly by the nut without cramping or binding upon the surface 26 of the reduced portion 56. The printing plate may thus be easily and quickly assembled upon the printing cylinder and after assembling the printing plates may be positioned upon a spindle in the machine and secured thereto by the set screw 50.

In some instances it will be desirable that printing cylinders of a complete circle or hoop be provided, as shown in Fig. 9. These will usually have suificient resiliency in them to permit of their being slid over either the flange l2 or 22 and after in position the binder may be set up to cause these edges to substantially contact and be bound firmly against the bear-er surface I5, 35, and 2!. In this case, of course, the threaded member 26 need not be used, and it will be returned into the threaded opening 25 sufiiciently so that it will not function. The abutted edges of the print plate may extend across the cylindereither parallel to the axis or at a sufficient angle thereto so that a doctor blade will not catch in the crevice. The crevice will be small but in some cases may be filled with bismuth solder or a gum. Plates not only with raised portions which are inked may be used, but also plates of the rotogravure type may also be used in this connection.

Referring to the modified form of structure shown in Figs. 1O, 11, 12 and 13 I have provided that a cushion be inserted between the printing plate and the bearer surface which the print whole is bound on the spindle which supports it by means of the integral split collars 44 and 45 which are contracted by the bolt 46. The bearer surface 4'! adjacent the inclined or undercut surface I3 is recessed as at $8 and an annular rubber ring 49 is positioned in this recess by stretching the same and allowing it to contract upon the surface of the recess. Likewise the surface 50 of the binder member is recessed or provided with a channel 5! and a rubber ring 52 is positioned therein. The relative sizes of the recess and the ring of rubber are such that the plate 31 will be positioned about one or. two thousandths from, the, bearer surfaces 4'! or 50, when the nut is turned up to bind the plate in desired position.

This cushioning action is desirable in the printing of cardboard, magazines, calendars, or such cushionable material, whereas the structure previously described and shown in Figs. 1 to 9 is more desirable for embossing or printing cards and the like. This cushioning eiTect also permits of printing where there is no resiliency back of the work, the entire resiliency being in the cylinder rather than in the usual make-ready back-up for the work, although it is necessary to have some resiliency back of the work where there is an embossing or cutting.

In the structure shown in Fig. 13 there are recesses 53 extending longitudinally of the cylinder 54 and rubber strips 55 cut from stock of even thickness are laid into these recesses so as to provide for the cushion similar to that which I have mentioned in connection with Figs. 10, 11 and 12.

The foregoing description is directed solely towards the construction illustrated, but I desire it to be understood that I reserve the privilege of resorting to all the mechanical changes to which the device is susceptible, the invention being defined and limited only by the terms of the appended claims. 1

I claim:

1.-A print cylinder and arcuate print plate comprising means providing a bearer for the back of said plate, means to engage one edge of the plate and fixed to the bearer, means to engage the other edge of the plate and movable with reference to the first said edge engaging means and carrying an adjustable support to limit axial movement at a point opposite a portion of the plate, and a nut to effect such movement.

2. A print cylinder and arcuate print plate comprising means providing a bearer for the ,back of said plate formed of separate sections one of which is interchangeable with other sections of varying axial dimensions, means to en-' gage one edge of the plate and fixed to the bearer, means to engage the other edge of the plate and movable with reference to the first said edge engaging means and carrying an adjustable support to limit axial movement at a point opposite a portion of the plate, and a nut to effect such movement.

3. A print cylinder and an arcuate print plate comprising a bearer for the back of said plate, an annular recess in the bearer surface, a circular resilient cushioning band in stretch condition positioned in said recess and means to bind-the edges of said plate against said cushioning means.

4. A print cylinder and an arcuate print plate comprising a bearer for the back of said plate, circular resilient cushioning bands in stretch condition and in spaced relation with each other positioned on said print cylinder and located between adjoining surfaces of the cylinder and said plate, and means to bind the edges of said plate against said cushioning bands.

5. A print cylinder and an arcuate print plate comprising a bearer for the back of said plate, a circular resilient cushioning band in stretch condition positioned on said print cylinder and located between adjoining surfaces of the cylinder and said print plate, and means to bind the edges of said plate against said cushioning means.

6. A print cylinder and arcuate print plate covering in arc of less than 360 comprising means providing a bearer member for the back of said ment of said binder member between the edges 1 of the arcuate plate.

CURT J. ROI-ILAND.

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