GB2144107A - Paper feed in a rotary printing machine - Google Patents

Abstract

A rotary printing machine comprises two roll carrier arms (3) which are pivotable about a central axis and which are drivably coupled by gear trains to a shaft carrying two drive pinions. The spacing from each other of the rotational axes of two rolls (13, 19) rotatably mounted between the arms and the spacing of the rotational axis of the arms from a base of the machine are smaller than the diameter of the complete roll (13). The arms (3) are arranged below a printing mechanism (2) and between two walls (1) of the machine, and in combination with a belt drive (14), which is couplable with the machine drive and pivotable against the roll winding (13) in a web connection setting thereof, and with a brush blade arm (18) which is stationary for the web connecting operation. The roll (13) is pivotable into the web connection setting through an upper pivot range against the brush blade arm (18) and, after the connecting operation has taken place and the belt drive (14) has been pivoted away again after reduction of the roll to a defined diameter, through a lower pivot range beyond a perpendicular intersecting the rotational axis of the carrier arms (3) into a charging setting. Subsequently, the arms are pivoted into a renewal setting and a roll take-up setting. <IMAGE>

Description

SPECIFICATION Paper feed in a rotary printing machine The present invention relates to a rotary printing machine, and has particular reference to a paper feed arrangement by which a web of paper can be fed without interruption of the machine operation.

In known winding spool arrangements, for example that of DE-AS 1 053 529, twoarmed spool or roll carriers are arranged with a fixed rotational axis connection at the frame walls of a winding spool stand. Such arrangements, due to the relatively large roll diameters, require very long carrier arms with a correspondingly large pivot range, in which case all other components must be arranged externally of this pivot range or else be pivotable out of this range. This includes brush blade arms, as for example known from CH-PS 428 789. Arrangements of this kind require a separate mode of construction with relatively large frame area in large and rigid frame walls.

These disadvantages are particularly noticeable in terms of space when larger machine units with several printing mechanisms are to be set up one behind the other and each printing mechanism is to be provided with a spool arrangement mounted in separate housing walls.

In DE-AS 1 235 335 there is proposed, for the avoidance of some of the afore-mentioned disadvantages, a space-saving, compact mode of construction for a rotatable winding spool arrangement. For this purpose, the two-armed spool carriers are no longer connected with a fixed central axis, but are mounted in short axle stubs at the side frame. The axial spacing of the two rolls on the carrier is in that case smaller than the diameter of the new roll so that relatively short carrier arms, permitting a low overall height from the base, could be employed.

A particular disadvantage of this arrangement is that after gluing the web of a new roll to the web of an old roll, this must be turned through an upper pivot range in order to be able to effect an exchange of the old roll. As a result, it is necessary to arrange all equipment for the connection process externally of the upper pivot range of the roll, which means that the roll arrangement has a high mode of construction with separate frame walls.

A further disadvantage is that it is only possible to glue the webs together by hand at standstill of the machine. It is doubtful that a fully automatic gluing-on of the web of the new roll to that of the old roll could be carried out, even at very slow speed of the machine, in view of the form of equipment that is provided. A drive acting on the roll spool is provided for the acceleration of the new roll, which drive is difficult to regulate to the speed of the web drawn off.

It would thus be desirable to eliminate the disadvantages while maintaining the advantages of the state of the art by developing a functionally reliable roll arrangement which is relatively economic in costs, material and space.

According to the present invention there is provided a rotary printing machine comprising two spaced apart side walls extending upwardly from a base, a printing mechanism arranged between the walls, and paper feed means to feed a paper web from a roll to the mechanism and comprising two arms which are arranged between the walls and below the printing mechanism to be rotatable about a common axis and which are provided with two mounting means each to detachably mount between the arms a respective one of two such rolls for rotation about a respective axis, the spacing of the axes of rotation of such rolls from each other and the spacing of the axis of rotation of the arms from the base being less than a predetermined maximum roll diameter, drive means to rotate the arms in unison to displace the mounting means between different settings, web connecting means arranged in a fixed position between the walls to connect the web of a new roll mounted on one of the mounting means to the web of an old roll mounted on the other mounting means, and a drive belt movable into and out of driving engagement with the periphery of such new roll for rotation thereof during such web connection, the drive means being operable to so rotate the arms as to move such new roll initially through an upper pivot range into a setting against the web connecting means for production of such web connection and for initial web withdrawal from the roll and subsequently through a lower pivot range into a setting for final web withdrawal after initial withdrawal from the roll of such a web length as to reduce the roll diameter to a predetermined value permitting the roll to pass, clear of the base, through a vertical plane containing the axis of rotation of the arms, and thereafter to move said one mounting means into settings for mounting thereon of a further new roll.

In a preferred embodiment the paper feed means comprises a rotatable two-armed roll arrangement in which the web of paper can be drawn from two exchangeable rolls, which are mounted on a two-armed roll carrier, one after the other in an automatic connecting operation without interruption of the web to be drawn off and without reduction in the machine speed. Each carrier arm is arranged in engagement with a respective one of two gear trains, which are connected together through tooth engagement with two pin ions carried on a shaft. The arrangement is executed in a compact construction so that a separate mode of construction can be dis pensed with. For this purpose, the axial spacing of the two rolls from each other and the spacing of the rotational axis of the carrier arms from the foundation or base of the machine is smaller than the diameter of the full reserve roll.The drive for the acceleration of the new roll makes possible a matching, without tearing of the web, of its circumferential speed to the speed of the web drawn off the old roll, the drive being so arranged that the compact mode of construction is retained.

The connecting operation between the web drawn off the old roll and the start of the web of the new roll is performed by a brush blade arm needing little space. The pivotable twoarmed roll arrangement is arranged between the side walls and immediately underneath the printing mechanism. This arrangement has the advantage that the frame area required in the separate mode of construction is no longer required and separate frame walls can be dispensed with. This advantage is particularly effective when several printing machines with roll arrangements are to be assembled one behind the other into a larger unit.The low and compact arrangement between the walls is facilitated because the twoarmed carried with the new roll is pivotable into gluing setting upwardly against a brush blade arm, which is stationary for the connecting operation, only in a range from zero to at most 1 5 degrees in dependence on whether the roll diameter has a maximum or minimum value. The brush blade arm is in that case arranged at a small spacing parallel to a tangent to the roll circumference and inclined by about 45" to the horizontal. The fixed arrangement of the blade arm allows the components otherwise required for the resetting to be dispensed with and permits integration within the printing mechanism.For acceleration of the new roll to the speed of the web of the old roll, a belt roller drive, which is couplable with the machine drive and pivotable into and out of engagement with the roll circumference, is arranged in an about horizontal setting between the printing mechanism and the circumference of the new roll in combination with the roll carrier and the brush blade arm. This belt roller drive, by contrast to drives which engage at the roll spool, by relatively simple means enables a reliable and exact matching of the circumferential speed of the new roll to the speed of the web drawn off the old roll spool and thus provides a secure connecting operation, without reduction in the machine speed, while avoiding tearing of the paper.The space-saving arrangement of pivotable roll carriers, belt roller drive and brush blade are also allows the new roll to be pivotable through a lower pivot range after the web connecting operation has taken place. For this purpose, the new roll is unwound to a defined diameter at which the roll radius is smaller than the spacing of the rotational axis of the roll from the base. Thereafter, the roll, which is being wound down, is pivotable through a lower pivot range into a charging setting and, after placing the further new roll in a position of readiness, into a renewal setting.

An embodiment of the present invention will now be more particularly described by way of example with reference to the accompanying drawings, in which: Figure 1 is a schematic side elevation of a printing machine embodying the invention, showing paper feed means with the web of a new roll connected to the web of an old roll and with a belt drive engaging the new roll; Figure 2 is a sectional view of the machine of Fig. 1 on the line A-A of Fig. 1; Figure 3 is a schematic side elevation of a plurality of such machines assembled in a larger machine configuration; Figure 4 is a schematic side elevation of the paper feed means in the same web connecting setting as in Fig. 1 but with a new roll of smaller diameter; Figure 5 is a view similar to Fig. 4 but with the new roll wound down to a defined diameter and the old roll removed;; Figure 6 is a view similar to Fig. 4 but showing carrier arms of the feed means in a charging setting; and Figure 7 is a view similar to Fig. 4 but showing the carrier arms in a renewal setting.

Referring now to the drawings, there is shown in Figs. 1 and 2 a printing machine comprising paper feed means arranged between two side walls 1 and underneath a printing mechanism 2. The paper feed means comprises two rotatable roll carrier arms 3 mounted on stub axles 4, which are arranged at the walls 1 and on which toothed gear wheels or rims 5 are mounted. The gear wheels or rims 5 are arranged in spaces betwen the walls 1 and the arms 3 and are drivingly connected by way of intermediate gear wheels 6 to pinions 8 fixed on a shaft 7.

The shaft 7 is driven by means (not shown) in order to change the settings, described more closely in the following, of the roll carrier arms 3.

The arms 3 are provided with mounting bearings 9 for a roll spindle 11 and mounting bearings 10 for a roll spindle 1 2. The axial spacing of the bearings 9 from the bearings 10, thus of the spindle 11 from the spindle 12, and the spacing of the rotational axis of the arms 3 from the foundation plane of the machine are smaller than a given maximum diameter of a full roll 1 3 of a paper web to be fed to the printing mechanism. A belt drive 14, which is couplable with the machine drive (not shown) and pivotable against the circumference of the roll 13, is disposed above the roll 1 3 when mounted in the bearings 9 of the arms 3.A brush blade arm 18, which is stationary and which serves for the gluing of the web 21 of the new roll 13 to the web 20 of an old roll 19, is provided with two guide rollers 1 6 and 1 7 and is arranged between the walls 1 and underneath an inking device 1 5 in the printing mechanism 2. The blade arm 18 extends at a small spacing from a tangent to the circumference of the roll 1 3 and is inclined at 45" to the horizontal. Disposed in the blade arm 1 8 are a brush (not shown) pivotable into an operative position and a separating knife (not shown).According to the diameter of the old roll 19, either the web 20 or, after the web connecting operation has taken place (as evident in Fig. 1), the web 21 is fed by way of the guide roller 1 6 to the printing mechanism 2.

Illustrated in Fig. 1 is a roll 1 3 which has a maximum diameter and which, after being accelerated by the belt drive 14 while disposed in a drive setting, has its web 21 connected to the web 20 drawn from the old roll 19, the web 20 then being severed. The web 21 from the roll 13 is then conducted by way of the guide roller 1 6 to the printing mechanism 2 and the belt drive 14 is pivoted out of its drive setting when the web connection has been completed. In the case of the roll diameter shown in Fig. 1, the web connecting operation takes place in a horizontal setting of the arms 3.If, however, the roll 1 3 has a smaller than maximum diameter as shown in Fig. 4, then it is pivoted by at most 15 upwardly against the brush blade arm 1 8 into an end setting defined by a light barrier.

This upper pivot range, limited to 15 , serves only to compensate for fluctuations between a maximum roll diameter and a smaller roll diameter.

Starting from the upwardly inclined or horizontal setting of the arms 3, the web 21 of the roll 1 3 is drawn off to reduce the roll to a defined diameter (Fig. 5) which makes it possible to move the roll downwardly in counterclockwise sense over the machine foundation.

In the meantime, the spool of the old roll 1 9 is removed, together with the spindle 12, from the bearings 10. When the afore-mentioned defined diameter of the roll 1 3 is reached, a switching pulse is triggered by a light barrier (not shown) and the shaft 7 and associated drive gearing pivot the arms 3 into a setting (Fig. 6) for unwinding of the rest of the roll 1 3 and charging of a new roll 13'.

The spindle-less portions of the arms 3 in that case move unhindered past the brush blade arm 18 and the belt drive 14.

In the charging setting, a new roll 13' with its spindle 11' is already placed ready between the printing mechanisms (Fig. 3).

After this operation, the arms 3 are pivoted into a renewal setting (Fig. 7), on the attainment of which the recesses in the opened bearings 10 are disposed below the spindle 11'. The roll 1 3' is subsequently displaced horizontally in the direction of the open bearings 1 0 and raised into the horizontal setting by pivoting of the arms 3 in clockwise sense (Fig. 1). The bearings 10 are now closed.

When a predetermined minimum diameter of the roll 1 3 is reached, the web gluing operation is initiated in known manner by way of a light signal (not shown), the new roll 13' being either in the horizontal take-up setting (Fig. 1) or in the upwardly pivoted setting (Fig. 4), with the belt drive 14 coupled with the machine drive and pivoted against the roll 1 3'. When the roll 13' is accelerated to the speed of the web 21 drawn from the roll 13, the web from the roll 13' is pressed by the brush (not shown) of the brush blade arm 1 8 against the circumference of the roll 13' and a glued connection thus effected, the old web 21 at the same time being severed by the knife. The afore-described operations are then repeated in the described sequence.

Claims (5)

1. A rotary printing machine comprising two spaced apart side walls extending upwardly from a base, a printing mechanism arranged between the walls, and paper feed means to feed a paper web from a roll to the mechanism and comprising two arms which are arranged between the walls and below the printing mechanism to be rotatable about a common ais and which are provided with two mounting means each to detachably mount between the arms a respective one of two such rolls for rotation about a respective axis, the spacing of the axes of rotation of such rolls from each other and the spacing of the axis of rotation of the arms from the base being less than a predetermined maximum roll diameter, drive means to rotate the arms in unison to displace the mounting means between different settings, web connecting means arranged in a fixed position between the walls to connect the web of a new roll mounted on one of the mounting means to the web of an old roll mounted on the other mounting means, and a drive belt movable into and out of driving engagement with the periphery of such new roll for rotation thereof during such web connection, the drive means being operable to so rotate the arms as to move such new roll initially through an upper pivot range into a setting against the web connecting means for prodution of such web connection and for initial web withdrawal from the roll and subsequently through a lower pivot range into a setting for final web withdrawal after initial withdrawal from the roll of such a web length as to reduce the roll diameter to a predetermined value permitting the roll to pass, clear of the base, through a vertical plane containing the axis of rotation of the arms, and thereafter to move said one mounting means into setting for mounting thereon of a further new roll.

2. A printing machine as claimed in claim 1, the drive means comprising a shaft provided with two pinions each drivably coupled to a respective one of the arms by way of a respective gear train.

3. A printing machine as claimed in either claim 1 or claim 2, the web connecting means comprising a brush blade arm disposed closely adjacent and extending parallel to a tangent to the circumference of such new roll in the setting for web connection and initial web withdrawal, said tangent extending at substantially 45 to the horizontal.

4. A printing machine as claimed in any one of the preceding claims, wherein the upper pivot range is equal to at most substantially 15'.

5. A rotary printing machine substantially as hereinbefore described with reference to the accompanying drawings.