US 3146709 A
Description (OCR text may contain errors)
Sept. 1, 1964 W` E. BASS ETAL METHOD AND APPARATUS FOR MOUNTING PRINTING SLEEVES Filed April 9, 1962 m II 2 Sheets-Sheet l INV TORS.' Wa dafijs BYJ EEO )f ATTORNEY Sept. 1, 1964 w. E. BAss ETAL METHOD AND APPARATUS FoP MOUNTING PRINTING sLEEvEs 2 Sheets-Sheet 2 Filed April 9, 1962 W@ M0 2W@ s" 70h11, In* r y :2 ATTORNEY United States Patent() 3,146,709 METHD AND APPARATUS FOR MOUNTING PRINTING SLEEVES Waldo E. llass, Little Falls, and John F. Kirby, Allendale, NJ., assignors to West Essex Printing Plate, Inc., Caldwell, NJ., a corporation of New Jersey Filed Apr. 9, 1962, Ser. No. 185,951 7 Claims. (Cl. lOl- 375) This invention relates in general to the art of printing in which rubber printing plates are mounted on mandrels for supporting the plates in a printing press; and the invention is particularly concerned with cylindrical bases or sleeves on which the printing plates are secured and which in turn are mounted on the mandrels.
It is, of course, necessary that the cylindrical base, which is in the form of a sleeve made of a suitable material, `for example, plastic material such a polyester resin, or metal, shall be firmly mounted on the mandrel, and it is highly desirable that the base or sleeve be easily and quickly applicable to and removable from the mandrel.
Therefore, important objects of the present invention are to provide a novel and improved method of applying and removing a cylindrical base for rubber or other ilexible printing plates to and from a mandrel, respectively, and to provide a combination of such a cylindrical base and a mandrel therefor which shall embody novel and improved features of construction whereby the cylindrical base or sleeve can be easily and quickly applied tot the mandrel, shall be firmly mounted Aon the mandrel and shall be easily and quickly removable from the mandrel for any desired purpose, for example, to facilitate the interchange of cylindrical bases or sleeves having different printing plates thereon to permit the running of different printing jobs in succession on the same press.
Another object of the invention is to provide such a combination wherein the mandrel shall be constructed in a novel and improved manner to permit the use of fluid under pressure, for example, compressed air in a new and improved way to facilitate application and removal of the cylindrical base or sleeve to and from the mandrel, respectively. Y
A further object is to provide a novel combination of such a mandrel and a stand or support therefor whereby the mandrel can be easily and quickly mounted in and removed from the stand or support and can be connected to a source of compressed air while the mandrel is mounted on the support.
Other objects, advantages and results of the invention will be brought out by the following description in conjunction with the accompanying drawings in which FIGURE l is a composite central vertical longitudinal sectional view through a mandrel, a plastic cylindrical base or sleeve having rubber plates thereon and a stand or support for the mandrel, illustrating the mandrel in the stand and the base separated from the mandrel;
FIGURE 2 is a composite side elevation and sectional view of the sleeve mounted on the mandrel;
FIGURE 3 is a central vertical longitudinal sectional view through a mandrel showing a modification of the invention;
FIGURE 4 is a transverse vertical sectional view approximately on the plane of the line 4-4 of FIGURE 3;
FIGURE 5 is a fragmentary central longitudinal sectional view through a mandrel showing another modification of the invention;
FIGURE 6 is a view similar to FIGURE 2 showing a modication of the invention; and
FIGURE 7 is a top plan view thereof.
Specifically describing the invention, the cylindrical base or sleeve A is shown as comprising a tubular cylindrical body 1 that is formed of a suitable material, for
f? as example, a polyester plastic material, the sleeve preferably being made from a sheet of material having its edges on the bias and disposed in abutting relation to each other, the sheet being held in cylindrical form by a tape or strip 2 of material such as paper helically wound on the exterior of the cylindrical body. Helically wound on the strip 2 is another preferably wider strip of material 3. The strip 3 may be in the form of what is commonly known in the trade as sticky back which comprises a strip of tough fibrous material such as paper having a pressure sensitive adhesive on both sides, permitting the rubber printing plates to be easily and quickly applied to the sleeve by the adhesive on the exposed surface of the strip, or the strip 3 may be adhesively applied to the strip 2 and the rubber plates can be applied to such a strip by additional adhesive applied between the plates and the outer surface of the strip. The overall thickness of the sleeve may be, for example, of the order of .G20 inch. With this construction, the sleeve is normally dimensionally stable in its length and has limited circumferential resilience.
In the most common practice, the cylindrical base or sleeve A will be applied to the mandrel B to serve as a backing or support for application of the rubber plates 4 to the sleeve, and in accordance with the invention, the mandrel B is cylindrical and of an external diameter approximately equal to the internal diameter of the base or sleeve A so that the sleeve may firmly frictionally engage the mandrel. The mandrel is hollow and has a chamber 5 which according to the present invention is used as a compressed air chamber. In the form shown, the mandrel comprises a cylindrical tube 6 having an interior surface formed with rabbets 7 in which are iitted with an airtight joint, end plates e and 9. One end plate S has a solid cylindrical trunnion or stub shaft 10 secured therein and projecting coaxially outwardly therefrom, while the other end plate of the mandrel has a similar trunnion 11 secured therein but provided with a longitudinal air passage 12 therethrough.
Associated with the mandrel is a stand C for both holding the mandrel in a vertical position and automatically connecting the chamber 5 of the mandrel with a source of compressed air. As shown, the stand comprises a base plate that has an upstanding boss 13 thereon in which is an upwardly opening recess 14 of a diameter slightly greater than that of the trunnion 11. An air duct 15 in the base plate has one end opening through the bottom of the recess 14 and its other end formed for connection to a coupling 16 for an air hose 17 the other end of which is connectible to an air compressor or other source of compressed air. In the bottom of the recess 14 is preferably set a packing disk 13 having an aperture in register with the end of the duct 15 so that air will ilow freely from the hose 17 through the duct15 and through the passage 12 in the trunnion into the air chamber 5. The cylindrical side wall of the tube 6 has a plurality of small transverse apertures 19 extending therethrough and spaced apart both circumferentially and longitudinally of the mandrel through which the air from the chamber 5 may escape. As shown some of these apertures are disposed in close proximity to the ends of the mandrel as indicated at 20, these particular apertures being shown as angular so that they may be formed in the end plates 8 and 9 and be directed outwardly through the peripheral surface of the mandrel, and as best shown in FIGURES 1 and 3, the apertures extend from points in close proximity to at least one end of the cylindrical wall a distance at least approximately equal to the length of the sleeve.
In operation of the invention, when it is desired to apply the sleeve A to a mandrel B, the mandrel is set in the stand as shown in FIGURE l and the compressed air is turned on, for example, by operation of a valve in the hose 17 (not shown). The chamber 5 thus becomes lled with compressed air which escapes in small jets through the apertures i9 and 2). One end of the sleeve is manually slipped onto the upper end of the mandrel the air jets serving to slightly expand the sleeve and provide in effect a lubricating film of air between the surface of the mandrel and the inner surface of the sleeve. The sleeve is then pushed downwardly on the mandrel, the air emerging from the apertures lg permitting free sliding of the sleeve onto the mandrel. After the sleeve has been completely applied to the mandrel as shown in FIGURE 2 the air may be cut off and the sleeve contracts into the tight frictional contact with the outer cylindrical surface of the mandrel body 6, whereupon the mandrel may be removed from the stand and mounted in a printing press as usual.
After the job has been completed on the press, the mandrel may be returned to the stand C in the manner above described, the air may be turned on and then the sleeve can be easily pulled upwardly from the mandrel, the air film formed by the air jets issuing from the apertures l? serving to slightly stretch the sleeve and act as a lubricating film so as to easily permit the sleeve to be slid off the mandrel.
A modification of the invention is shown in FIGURE 3 where provision is made for introduction of air into the chamber 5 in a different manner than that above described. Here both trunnions 2l and 22 corresponding to the trunnions l and ll may be solid, and one of the end plates has a transverse opening 23 therein to which is connected a coupling element 24 for an air hose 25. The hose 25 is connected to a source of compressed air and preferably has a control valve therein. in this form of the invention, the air enters the chamber through the opening 23 instead of through the trunnion.
Also, the air may be used to facilitate slight adjustments of the sleeve on the mandrel while the latter is mounted in the printing press if desired, it being obvious that if the air hose is connected to the coupling element 24 and the air is turned on, the sleeve can be easily slid in either direction on the mandrel.
Such adjustment of the sleeve could also be effected by screw-threading as indicated at 26 in FGURE 1 the outer end portion of the passage l2 for connection on a hose coupling directly to the passage. Also, the passage in the trunnion 27 may have a portion 28 extending longitudinally of the trunnion outwardly from the chamber 5 and another portion 29 communicating with the portion 23 and opening through the periphery of the trunnion and screw threaded for connection to a hose coupling, as shown in FIG. 5.
The invention may also be used in conjunction with tubular mandrels that have open ends without end walls. Such a mandrel C is shown in FIGURE 6 and has apertures 39 corresponding to the apertures 19. For this type of mandrel, a different form of stand or support is utilized and is shown as comprising a base 3l having a boss 32 upstanding therefrom on the upper end of which is seated a rubber gasket 33 on which one end of the tubular mandrel is set. At the other end of the tubular mandrel is a rubber gasket 3d on which is superimposed a metal washer 35. The mandrel is clamped firmly in position on the base with both its ends air-tightly closed by a bolt 37 that extends through an opening 38 in the base and has a head 39 at one end abutting the base with its other end having a quick-acting screw or cam 46 with which coacts a quick-acting nut or knob 4l that bears aaginst the washer 35 so as to clamp the gasket 34 against the tubular mandrel. Compressed air is injected into the mandrel through a passage 42. in the base, one end of which opens through the gasket 33 into the mandrel and the other end of which has a suitable hose connection 43 to be attached to a source of compressed air.
The cylindrical base or sleeve A may be applied or removed from the mandrel C in the same manner as hereinbefore described.
It will also be understood that the mandrel may be mounted with its axis horizontal instead of vertical, for example, by resting one of the trunnions 21 or 22 in a V-support block and the other trunnion in a socket in one end of an extension shaft the other end of which is supported in a V-block so that the cylindrical base can initially be slipped over the extension shaft and then the mandrel trunnion can be fitted into the socket of the shaft after which the cylindrical base can be slipped over the mandrel in the same manner as hereinbefore described, the sleeve being removable from the mandrel in the manner hereinbefore described onto the extension shaft which is then disconnected from the mandrel which can then be temporarily supported in V-blocks. The apparatus is generally known and no claim to novelty per se is made thereon.
Modifications and changes in the construction of the sleeve, the mandrel and the stand will occur to those skilled in the art as being within the spirit and scope of the invention.
1. A method of applying and removing a cylindrical base sleeve for printing plates to and from the cylindrical outer surface of a mandrel, respectively, wherein said base sleeve has circumferential resilience and an interior diameter such that the sleeve will snugly engage said cylindrical surface of the mandrel, said method consisting in causing small jets of gas under pressure to issue laterally from said outer surface of said mandrel at a plurality of points spaced circumferentially and longitudinally of said cylindrical surface from points in close proximity to at least one end thereof a distance at least approximately equal to the length of said sleeve while sliding said base sleeve longitudinally over said cylindrical surface.
2. The combination of a mandrel for supporting a cylindrical base sleeve bearing printing plates in a press, said mandrel comprising a tube having a cylindrical wall through which extend a plurality of small apertures that are spaced apart circumferentially and longitudinally of said cylindrical wall from one end thereof a distance at least approximately equal to the length of said base sleeve, and means removably associated with both ends of said tubular mandrel for temporarily closing them, and means for admitting gas under pressure into said mandrel while said ends are closed.
3. The combination of a mandrel for supporting a cylindrical base sleeve bearing printing plates in a press, said mandrel comprising a tube having a cylindrical wall through which extend a plurality of small apertures that are spaced apart circumferentially and longitudinally of said cylindrical wall from one end thereof a distance at last approximately equal to the length of said base sleeve, an element removably associated with each end of said mandrel for closing said end, means extending through said mandrel for separably connecting said elements and holding them in closing relation to the respective ends of the mandrel, one of said elements being formed for admission therethrough of gas under pressure into said mandrel while said ends are closed.
4. A mandrel for supporting in a printing press a cylindrical base sleeve having limited inherent circumferential resilience, said mandrel comprising a body having a cylindrical side wall whose external diameter is approximately equal to the internal diameter of the base sleeve and two end walls providing a closed chamber from which extend through the cylindrical wall a plurality of small apertures that are spaced apart circumferentially and longitudinally of the cylindrical wall and certain of which are placed closely adjacent the ends of said cylindrical Wall, and a trunnion projecting outwardly from each end wall coaxially with said cylindrical side Wall, there being means for admitting air under pressure into said chamber comprising an opening through one of said end plates between the corresponding trunnion and said cylindrical side wall, and means for connecting said opening to a source of compressed air.
5. The combination of a mandrel for supporting in a printing press, a cylindrical base sleeve having inherent circumferential resilience bearing printing plates, said mandrel comprising a body having a cylindrical side wall whose external diameter is approximately equal to the internal diameter of the base sleeve and two end walls providing a closed chamber, said cylindrical wall having a plurality of apertures extending therethrough from said closed chamber that are spaced circumferentially and longitudinally of the cylindrical Wall and certain of which are disposed in close proximity to one end wall, and a trunnion projecting outwardly from each end wall coaxially with said cylindrical side wall, there being means for admitting air under pressure into said chamber, and a stand supporting said mandrel with its axis in vertical position comprising a base plate having an upwardly opening recess in the upper side thereof of a diameter slightly greater than that of one of the trunnions and into which the trunnion opposite said one end wall is removably and coaxially fitted, so that the mandrel is held in upright position to permit a cylindrical base sleeve to be manually pushed onto the mandrel over the upper end thereof, when air under pressure is admitted to said mandrel.
6. The combination as defined in claim wherein the means admitting air into said chamber comprises a longitudinal passage through said trunnion and a duct in said base plate having one end extending through the bottom of said recess to communicate with said passage in said one trunnion, and means for connecting the other end of said duct to a source of compressed air.
7. The combination of a mandrel and a cylindrical base sleeve rmly frictionally fitted thereon for supporting printing plates, said mandrel comprising a body having a cylindrical side Wall Whose external diameter is approximately equal to the internal diameter of said base sleeve and two end walls providing a closed chamber having an inlet passage for gas under pressure, said cylindrical wall having a plurality of small apertures extending therethrough from said closed chamber that are spaced circumferentially and longitudinally of the cylindrical wall and certain of which are disposed in close proximity to one end wall, means for connecting said inlet passage to a source of gas under pressure and a trunnion projecting outwardly from each end wall coaxially with said cylindical side wall, said cylindrical base sleeve having some inherent circumferential elasticity and having an inner peripheral surface of a diameter substantially equal to the diameter of the outer peripheral surface of said cylindrical side wall of the mandrel and being normally tightly tted on said outer peripheral surface of said cylindrical side wall, said combination enabling manual sliding of the base sleeve onto and otr" the cylindrical wall with a film of gas under pressure from said apertures between the outer peripheral surface of the cylindrical wall and the inner peripheral surface of the sleeve and the sleeve irmly frictionally fitting on said cylindrical wall when no gas is emerging from said apertures.
References Cited in the tile of this patent UNITED STATES PATENTS 2,060,082 Johnson et al. Nov. 10, 1936 2,721,601 Spencer Oct. 25, 1955 2,782,459 Moncrieff Feb. 26, 1957 3,078,796 Kamata et al Feb. 26, 1963