REGISTRATION BARS

Abstract: It is known to locate a reference bar in spaced relation to a printing roll to enable the application of a polymer sheet to the roll, and the closer the reference bar is to the roll, the greater is the accuracy of location of the sheet on the roll. However, in known equipment, and to allow more than one roll diameter to be handled, a reference bar is fixed in relation to a support for the roll at a distance to accommodate a roll of largest diameter, and the smaller is the diameter of the roll, the greater is the distance of the surface of the roll from the reference bar. The object of the invention is to avoid this disadvantage, which objective is met by a support means for a registration bar (5) comprising an angled support member (8) one leg (9) of which is provided with a hinged connection to a support (10), and the second leg (7) of which is adjustably mounted on the said one leg, said registration bar (5) being adjustably mounted on said second leg (7) of said support member (8).

Description: REGISTRATION BARS This invention relates to registration bars, and is particularly concerned with the location of a registration bar with respect to a printing roll. It is common practice in the printing industry to locate a printing roll in parallel spaced relationship to a reference bar, and whereby flexible polymer sheeting can be first positioned on the reference bar by the engagement between reference pins on the bar and reference holes in the sheeting, following which the free end of the sheeting can be brought into engagement with the roll to be wrapped on the roll at a required location along its length. Thus, it is known to locate a reference bar in fixed spaced relationship to bearing blocks to support the spindle of the printing roll, and as the equipment must be capable of accepting rolls of different diameters it will be understood that the distance between the reference bar and the bearing blocks must be such that there is no impeding of the placement on and removal from the bearing blocks of the largest printing roll that the equipment is intended to accommodate. It is equally so that the closer is the reference bar to the surface of the printing roll the greater is the control over the accuracy of location of the sheeting on the roll, and with the existing equipment, rolls of a diameter less than the permitted maximum inevitably have a greater spacing from the reference bar to the detriment of the control over the accuracy of location of the sheeting on the roll. It is the object of the invention to provide for the location of a reference bar with respect to a printing roll such that those disadvantages mentioned above are avoided. According to the present invention, a support means for a registration bar comprises an angled support member one leg of which is provided with a hinged connection to a support, and the second leg of which is adjustably mounted on the said one leg, said registration bar being adjustably mounted on said second leg of said support member. Preferably, two angled support members are provided to support the reference bar at each end thereof. The angled support member may be of generally L or T- shaped configuration, with the adjustable connection between the said one and second legs allowing the height of the second leg to be varied and the adjustable connection of the reference bar to the second leg allowing the distance of the reference bar from the said one leg to be varied, both to suit a particular diameter of a roll to which flexible polymer sheeting is to be applied. Thus, the angled support members can be swung to an inoperative position to allow a printing roll to be located by its spindle in bearing blocks on the support, and with the roll in place, the support members swung back to the operative position. The hinged connection of the said one leg can embody stop means to locate the support member in its operative position, following which the height of the second leg on the first leg can be adjusted, and the position of the reference bar on the second leg can be adjusted, such that the reference bar is positioned in close spaced relationship to the surface of the roll and preferably co-planar with the outer edge of the printing roll. Thus, with a polymer sheet secured to the reference pins on the reference bar, the sheet hangs directly alongside the printing roll, to the considerable benefit of the accuracy of wrapping the sheet on the roll. To assist in the equipment accommodating rolls of different diameter, and in place of stop means associated with the hinged connection between the said one leg and the support, it is preferred to provide bearing means on the said second leg, which, in use, contact the surface of the roll, and such that with the two adjustments referred to above for a specific roll diameter, contact between the bearing means and the roll surface guarantees the positioning of the reference bar in relation to the roll surface. Preferably, the bearing means is a roller secured to the second leg. In addition to the bearing blocks for the roll spindle, it is highly desirable to provide adjustable tail stocks that can be brought into engagement with the ends of the roll spindle, thereby to guarantee that there will be no transverse movement of the roll during the wrapping of the sheet on the roll. Ordinarily, a number of such sheets are positioned in side-by-side relationship along the roll, and for one sheet to be positioned correctly with relation to an adjacent sheet, the roll may need to be rotated following the wrapping of one sheet and the wrapping of the succeeding adjacent sheet. Therefore, it is preferred to provide an indexing means secured to the spindle of the roll and whereby any required rotation of the roll can be effected with considerable accuracy. One embodiment of the invention will now be described by way of example with reference to the accompanying drawings, in which:- Figure 1 is a perspective view of a support means for a registration bar, in accordance with the invention; and Figure 2 is a section generally on the line II-II of Figure 1. In the drawings, a printing roll 1 is shown located in bearing blocks 2 mounted on a table 3, the bearing blocks being adjustably mounted to enable rolls of different length to be accommodated. Also adjustably mounted on the table 3 are tail stocks 4 to abut the ends of the roll spindles and to prevent transverse movement of the roll. As is shown mere particularly by Figure 2, a reference bar 5 bearing reference pins 6 is adjustably secured to the fi¬ end of one Peg 7 of a generally L or T-shaped support member 8, the leg 7 being adjustably mounted on the other leg 9 of the support. The leg 9 is pivotally mounted in support blocks 10 secured to the table. Towards the outer end of the leg 7 of the support, a bearing roller 11 is provided on an underslung support member 12 having a number of holes 13 for adjustably positioning the roller 11. Thus, at the onset, the two reference bar supports 8, along with the reference bar are swung rearwardly of the table to provide unrestricted axis of the printing roll 1 to position the printing roll 1 in its bearing blocks 2, the printing roll then being moved as required horizontally to align the printing roll with the reference bar, and the tail stocks 4 then screwed up into contact with the ends of the roll spindles and hence prevent further horizontal movement of the rolls. The reference bar supports are then swung back to the operative position, and the height of the leg 7 on the leg 9 adjusted and the bearing roll 11 located along its support 12 such that the reference bar 5 is in a vertical disposition with the bearing roll in contact with the printing roll at approximately its top dead centre. The reference bar 5 is then adjusted on the leg 7 such that it is substantially co- planar with the outer edge of the printing roll. By these means, the lower edge of the reference bar and hence the reference pins on the registration bar can be positioned in very close proximity to the printing roll surface, irrespective as to the diameter of the roll, within the limit of the height of the legs 9 of the support 8. Therefore, a flexible polymer sheet 13 can be located on the reference pins by holes strategically formed at the edge of the sheet and the sheet wrapped on to the roll with ease. In certain circumstances and where more than one sheet is to be wrapped on the roll 1, a second sheet may, by virtue of its subject matter, need to be offset in relation to a first sheet. Thus, an indexing means 14 is provided formed by a toothed wheel in a housing 15 having access holes 16, to fit over the spindle of the printing roll. Mounted on the table alongside the housing 15, is a stop bar 17 with an inturned projection 18, pivotally mounted on a support 19 and with a screw operating mechanism 20. At the outset, the stop bar can be lowered for the projection 18 to penetrate a hole 16 to engage the toothed wheel and hold the roll against rotation. When rotation of the roll is required, the stop bar is raised and the roll along with the housing 15 rotated to bring a second hole 16 of a predetermined circumferential spacing to a position where the stop bar can be lowered for the projection 18 to pass through it to engage the toothed wheel, and hold the printing roll at a required displacement and to allow correct positioning of a second polymer sheet on the printing roll. An advantage of the invention is its ability to accommodate rolls of a variety of diameters, but a further advantage is that when a second roll is presented, of the same diameter as the first roll, all the settings previously applied can remain, and the reference bar supports and the reference bar swung back to allow the roller 11 to contact the second roll with the certainty that the reference bar is correctly positioned in relation to the roll edge.

Claims: CLAIMS 1. A support means for a registration bar comprising an angled support member one leg of which is provided with a hinged connection to a support, and the second leg of which is adjustably mounted on the said one leg, said registration bar being adj ustably mounted on said second l eg of said support member. 2. A support means as in Claim 1 wherein two angled support members are provided to support the r eference bar at each end thereof. 3. A support means as in Claim 1 or Claim 2 , wherein the or each angled support member is of generally L or T- shaped conf iguration, with the adjustable connection between the said one and second legs allowing the height of the second leg to be varied and the adj ustabl e connecti on of the reference bar to the second leg all owing the distance of the reference bar from the said one leg to be varied, both to suit a particular diameter of a roll to which flexible polymer sheeting is to be appl ied. 4. A support means as in any of Claims 1 to 3 , wherein the hinged connection of the said one leg embodies stop means to locate the support member in its operative position. 5. A support means as in any of Claims 1 to 3 , wherein bearing means are provided on the said second leg which, in use, contact the surface of the roll. 6. A s uppor t means a s in Cl ai m 5 , wher ei n the bearing means is a bearing roller. 7. A support means as in any of Claims 1 to 6, wherein adjustable tail stocks are provided to engage with the ends of the roll spindle. 8_ A support means as in any of Claims 1 to 7, wherein an indexing means is secured to the spindle of the roll and whereby any required rotation of the roll can be effected with considerable accuracy. 9. A support means for a registration bar substantially as hereinbefore described with reference to the accompanying drawings.

Inventors: CARR MICHAEL DAVID, GOVIER ROLAND DAY, CARR, MICHAEL, DAVID, GOVIER, ROLAND, DAY
Applicants: TECFLEX LTD, TECFLEX LIMITED
Application year: 1990
Main classification: B41F27
IPC codes: B41F27