GB2195322A - Linerboard roll mounting device in a corrugator - Google Patents

Description

1 GB2195322A 1

SPECIFICATION

Linerboard roll mounting device in a corrugator This invention relates to a linerboard (card- board) roll mounting device in a corrugator, more particularly to a linerboard roll mounting device having a constitution wherein automatic chucking of a linerboard roll by swing arms in a mill roll stand can be facilitated by a rocking movement of said swing arms even in a roll whose diameter has been greatly reduced after feeding of the linerboard for processing in said corrugator.

There has widely been used corrugators having a constitution wherein a corrugating means is allowed to have a corrugation with the desired pitch size; said means is pasted together with a liner at the crests of the corrugation using an adhesive to provide a singlefaced corrugated board sheet; and the thus obtained single-faced corrugated board is pasted together with a back liner to provide a double-faced corrugated board sheet. In such corrugators, while a single facer for producing the single-faced corrugated sheet and a double facer for pasting the single-faced corrugated sheet obtained above with the back liner are used as the main devices, linerboard roll mounting devices for feeding the corrugating means, the liner and the back liner as well (these webs are hereinafter referred to as "linerboard") to said single facer and double facer respectively are inevitable as auxiliary equipments.

The linerboard is mounted to the linerboard roll mounting device in the form of a roll having a predetermined diameter taken up around a paper tube as a core (hereinafter referred to 105 as "linerboard roll"), from which the linerboard is fed or supplied. In accordance with the order change in such corrugated board in the process of production, said linerboard roll is removed from the linerboard roll mounting 110 device, loaded on a conveyor such as a flat car and carried to a specified stockyard.

As a conventional linerboard roll mounting device to be employed in a corrugator, a mill roll stand of so-called swing arm system as 115 shown in FIG. 11 is widely known. This mill roll stand shown with the numeral 1 is pro vided with two pairs of swing arms 3 and 4, each pair being rotatably supported by hori zontal rocking shafts 30 on its both end por120 tions, respectively, and center blocks 10 which can be inserted to the paper tube 2a of the linerboard roll are provided each at the tip end portion of the arms 3 and 4. A roll con- veyance/supplementation track is provided on 125 the floor of the factory site extending from the mill roll stand 1 toward two opposing di rections, for carrying the linerboard roll. 2 to and from said mill roll stand 1.

To mount the linerboard roll 2 to said mill 130 roll stand 1, the swing arms 4 located at the right side rocking shaft 30 are turned down toward the linerboard roll 2 loaded on the conveyor 13 having been carried along said conveyance route. Subsequently, a pair of opposing center blocks 10 are moved toward both ends of the paper tube 2a in the roll to achieve chucking thereof, and then said swing arms 4 are rocked upward to return to their original position, and the linerboard roll 2 will thus be mounted to the mill roll stand 1. The above procedure can be repeated with respect to the swing arms 3 provided at the left side rocking shaft 30 to carry out mounting of another linerboard roll 2.

Recently, it is demanded that a corrugator can cope properly with the production of corrugated board sheets from smaller lots of linerboard rolls. And in such a circumstance, it is frequently required to repeat an operation of removing a linerboard roll from the arms before it is used up, to be replaced with another linerboard roll in compliance with the next order. Thus, the aforementioned mill roll stand suffers disadvantage that, with a linerboard roll whose roll diameter has greatly been reduced after feeding of the linerboard for processing, automatic chucking of said linerboard roll by the swing arms cannot be achieved only by moving the swing arms to its lowest rocking position.

Namely, a brake means 32 is provided to each center block 10 fixed at each tip end of - the swing arms coaxially with the center blocks in order to prevent excessive feeding of linerboard which might otherwise occur due to rotary inertia of the linerboard roll 2, such that the brake means 32 can exert braking power to the rotation of said center blocks 10. However, this brake means 32 comes large in diameter because of its construction, the minimum distance between the center blocks 10 and the floor of the factory site that the former can attain will thus naturally be limited. For example, as shown in FIG. 12, the height of the center C1 of the center block 10 from the floor of the factory site cannot be less than hl. Therefore, if the height h2 of the paper tube center C2 of the linerboard roll 2, whose roll diameter has greatly been reduced after feeding of the linerboard for processing, from the floor of the factory site should become smaller than said height hl (h2 < hl) as shown in FIG. 12, said center C1 of the center block 10 cannot reach the paper tube center C2 of the linerboard roll 2 loaded on the conveyor 13. In such an occasion, automatic chucking of the linerboard roll by the center blocks cannot be achieved, and the linerboard roll 2 must be lifted up by two or more operators to fit the end portions of the paper tube 2a with the corresponding center blocks 10 respectively, which is a complicated and laborious operation.

2 GB2195322A 2 SUMMARY OF THE INVENTION This invention has been proposed in view of the above disadvantages inherent in the prior art linerboard mounting device in a corrugator and to improve such disadvantages, and is directed to provide a linerboard mounting device in a corrugator, wherein a sensor detects the diameter of the linerboard roll to be chucked by the swing arms of the mill roll stand; and said linerboard roll is lifted up with a lifter to the waiting position of the swing arms, when the value resulted from the above detection is determined to be insufficient for the center blocks to reach the paper tube of said liner- board roll if the swing arm of the mill roll stand is moved to its lowest rocking position, to allow alignment of the center block and paper tube of the linerboard roll to achieve automatic chucking thereof, thereby the labor to be required of the operators can be reduced and also working efficiency may be improved.

BRIEF DESCRIPTION OF THE DRAWINGS

The objects and characteristics of the liner- board mounting device in a corrugator accord ing to this invention will be understood more clearly by referring to the detailed description of the embodiments taken in conjunction with the attached drawings.

FIG. 1 is an illustration of a linerboard mounting device according to a preferred em bodiment of this invention in plan view; FIG. 2 is a plan view of the mill roll stand to be used in the linerboard mounting device according to 100 the preferred embodiment of this invention; FIG. 3 is a side view of a mill roll stand; FIG.

4 illustrates constitution of a conveyor means; FIG. 5 is a cross-sectional view of the con veyor means; FIG. 6 is a block diagram of a 105 control device; FIG. 7 is a time chart when the linerboard mounting device according to the preferred embodiment is operated; FIG. 8 illustrates constitution of a second embodi ment of the diameter detecting sensor; FIG. 9 110 illustrates the third embodiment of the dia meter detecting sensor; FIG. 10 illustrates a fourth embodiment of the diameter detecting sensor; FIG. 11 is a perspective view of a mill roll stand of swing arm system showing its 115 constitution schematically; FIG. 12 illustrates a mill roll stand as shown in FIG. 11 in a state that chucking of the linerboard roll by the cen ter blocks is not feasible with the linerboard roll whose roll diameter has greatly been re- 120 duced in the mill roll stand as shown in FIG.

11.

DESCRIPTION OF PREFERRED EMBODIMENTS

The linerboard roll mounting device in a corrugator according to this invention will be described by-way of preferred embodiments and referring to the attached drawings. FIG. 1 shows an overall constitution of the linerboard mounting device according to this invention in plan view, in which the numeral 1 shows a mill roll stand. The mill roll stand 1, as shown in FIGS. 1 to 3, supports a pair of swing arms 3 and 4 such that they can swing around the guide rod 7 which swing arms 3 and 4 having been constituted such that they can chuck the linerboard rolls 2 independent of each other. The swing arms 3 and 4 are adopted to slide along the guide rod 7 when forced by the hydraulic cylinders 5 and 6 to move positively or negatively, respectively, as shown in FIGS. 2 and 3. Each guide rod 7 is connected to another hydraulic cylinder 8 via a lever 9 as shown in FIG. 3, such that the swing arms 3 and 4 may be rocked with a required central angle when forced by the hydraulic cylinder 8 to move positively or negatively.

A pair of opposing center blocks 10 are provided at the internal side of each tip end portion of the swing arms 3 and 4, which center blocks are removably inserted to the paper tube of the linerboard roll 2 at both ends; one of the center blocks 10 having a light emitting element 11 and the other center block 10 having a light receiving element 12. The above set of light emitting element 11 and the light receiving element 12 detect the hollow space of the paper tube in said liner- board roll 2 when the swing arms 3 and 4 are rocked down toward the linerboard roll 2 and to give command to said swing arms 3 and 4 to slide closer to chuck said roll 2.

On the other hand, a conveyor means 13 is provided for traveling freely between the stockyard for storing various sorts of linerboard rolls 2 of different paper quality and the position below the rocking locus of the swing arms 3 and 4. This conveyor means 13 comprises a track groove 15 provided in the floor extending from the stockyard to the mill roll stand 1 and a carriage 16 provided in said track groove 15 to travel freely therealong. The track groove 15 is formed of a pair of Ushaped section steel 14 as shown in FIGS. 4 and 5. Also, the carriage 16 is formed to have a T-shaped cross-section, and wheels 17 are rotatably supported on its sides at the front and rear portions.

On said carriage 16, a lifter 18 is provided having a constitution in which a motor drives a screw to turn to operate a link mechanism 19, and thereby a roll loading bed 20 is allowed to move vertically. This lifter 18 to be employed is not [imitative to this type of link mechanism and an application of a mechanism in which a hydraulic cylinder is used as a driving source is also feasible. It should be noted that a required dent is provided on the surface of the roll loading bed 20 at an appropriate portion such that the linerboard roll 2 may be stabilized thereon.

Each end of draft chain 21 is connected to said carriage 16 at the fore and rear ends.

This draft chain 21 is extended around 7 :k 3 GB2195322A 3 sprockets 22 pivoted at both ends of the track groove 15, one at the side of the stockyard and the other at the side of the mill roll stand 1 and one of the above sprocket is 5 driven by a motor (not shown).

Various types of sensors are provided in and in the periphery of said mill roll stand 1 as shown in FIG. 1. Namely, a diameter detecting sensor 23 which detects the roll dia- meter of a linerboard roll 2 to be mounted to said mill roll stand 1 is provided a little bit short of the mill roll stand 1. As the diameter detecting sensor 23, a sensor utilizing ultrasonic wave may preferably be used. In the case where an ultrasonic sensor 23 is used, said sensor is adopted to receive an ultrasonic wave having been emitted from an emitter toward the linerboard roll 2 and reflected therefrom, and determine the distance from the emitter to the exterior surface of the linerboard roll 2 to calculate the diameter of said linerboard roll 2.

Also, in or in the periphery of said mill roll stand 1, an incoming roll recognizing sensor 24 is provided for detecting arrival of the linerboard roll 2 loaded on the conveyor means 13 at the position below the swing arms 3 and 4 of the mill roll stand 1. Further, roll offset sensors 25 and 26 are provided for detecting offset in the positioning of the linerboard roll 2 carried in by the conveyor means 13. A photoelectric sensor is suitably used as such incoming roll recognizing sensor 24 and roll offset sensors 25 and 26.

On the other hand, with respect to the con- 100 veyor means 13, there is provided a limit switch LS1 for recognizing the terminal lot which is to be turned on when the carriage 16 is abutted on it, such that the carriage 16 can recognize said lot; whereas with respect 105 to the mill roll stand 1, there is provided a limit switch LS2 for sensing the incoming roll, which is to be turned on at the sensing posi tion of the terminal lot. Said lifter 18 is also provided with an upper limit switch L83, which is to be turned off at the upper limit of said lifter 18, and a lower limit switch LS4 which is to be turned off at the lower limit of said lifter. The above upper limit switch LS3 and the lower limit switch LS4 are integrated 115 in the lifter control circuit 27 which controls the ascending movement of the lifter 18 as shown in FIG. 6. This lifter control circuit 27 is connected to a main control circuit 28 which has already been provided. The main control circuit 28, as well known in the art, is designed to control the chucking operation in the mill roll stand 1. The notation SW1 in FIG. 1 shows an AUTO/MANUAL change over switch.

In order to allow mounting of the linerboard roll 2 in compliance with the order for the paper quality of corrugated board sheet to be produced to the mill roll stand 1, the corre- sponding linerboard roll 2 having the desired paper quality is first selected from the rolls stored in the stockyard and the selected roll 2 is loaded on the lifter 18 of the conveyor. means 13. By driving one of the sprockets 22 for rotation by means of a motor not shown, the carriage 16 loading the linerboard roll 2 is drafted by the draft chain 21 to travel from the stockyard toward the mill roll stand 1. When the carriage 16 approaches the mill roll stand 1 as it travels, said diameter detecting sensor 23 detects the roll diameter of the linerboard roll 2 on the roll loading bed 20 and sends the detected data to the lifter control circuit 27 as shown in FIG. 7. In this lifter control circuit 27, judgment is made whether the diameter of the linerboard roll 2 is smaller or larger than the predetermined value (i.e. whether the center blocks in the arms can be aligned with the paper tube of said linerboard roll 2 or not).

During the above process, the incoming roll recognizing sensor 24 confirms the presence of the linerboard roll 2 to be carried in. The carriage 16 further travels to reach the rear end of the terminal lot of the mill roll stand 1, where the limit switch LS1 for recognizing the terminal lot is turned on to transmit a message to the main control circuit 28 as a signal, that the carriage 16 is reaching the terminal lot. With the transmission of the signal by this main control circuit 28 to the lifter control circuit 27, the roll offset sensor 25 detects said signal to transmit the offset detection signal to the lifter control circuit 27. The lifter control circuit 27, upon receipt of said offset detection signal, recognizes that the linerboard roll 2 is ready to be lifted up by the lifter 18 and retains this state. When the carriage 16 further travels to reach the central portion of the terminal lot, the limit switch LS2 for sensing the incoming roll is turned on, and it is thus detected that the linerboard roll 2 on the carriage 16 has reached the center of the terminal lot. Said detection signal is transmitted from the limit switch LS2 for sensing the incoming roll to the lifter control circuit 27. The lifter control circuit 27, transmits said detection signal, i.e. the positioning completion signal, to the main control circuit 28, whereby to stop traveling of the carriage.

On the other hand, the lifter control circuit 27 actuates the lifter 18 after judgment based on the detected data obtained from the diameter detecting sensor 23 and lifts up the linerboard roll 2 to the predetermined level at which the upper limit switch LS3 is turned off. At the same time, the mill roll stand 1 initiates chucking operation upon receipt of the command from the main control circuit 28 with the completion of the positioning of the linerboard roll 2. In other words, the swing arms 3 and 4 are moved (rocked) downward with the span therebetween being opened wider than the width of the linerboard roll 2 until said light emitting element 11 and the 4 GB2195322A 4 light receiving element 12 detect the hollow space of the paper tube of the linerboard roll 2. Upon detection of the hollow space of the paper tube by the light emitting element 11 and the light receiving element 12, the swing arms 3 and 4 are moved closer to each other under the command of the main circuit 28 to grasp the paper tube at both ends therebetween. Subsequently, said swing arms 3 and 4 are moved upward back to the predet-ermined position to complete the mounting operation of the linerboard roll 2 to the mill roll stand 1.

During this mounting operation, the main control circuit 28 transmits a command of 11 under mounting operation" to the lifter control circuit 27. After completion of the mounting operation, the lifter control circuit 27 releases retention of the signal of "ready for lifting up" and allows the lifter 18 to descend until the lower limit switch LS4 is turned off, as well as to terminate transmittance of the 11 positioning completion signal" to said main control circuit 28. If said carriage 16 should accidentally run over the terminal lot, the limit switch LS1 for recognizing the terminal lot is turned off and also the roll offset sensor 26 is turned on such that when the lifter control circuit 27 recognizes the "ready for lifting up" message and retains that state, said recognition may be canceled to protect the lifter 18 from actuation.

When the linerboard roll 2 mounted between the swing arms 3 and 4 is to be car- ried out, the swing arms 3 and 4 are turned downward, and then the center blocks 10 are slid outward to allow the linerboard roll 2 to drop onto the carriage 16. Next, the carriage 16 travels to the stockyard, where the liner- board roll 2 loaded on the carriage 16 is unloaded.

When it is determined that the roll diameter of the linerboard roll 2 to be carried in by the carriage 16 has the predetermined size of dia- meter as a result of the detection by the diameter detecting sensor 23, automatic mounting of the linerboard roll 2 to the mill roll stand 1 can be achieved by the rocking operation of the swing arms 3 and 4 as has conventionally be done without the aid of the lifter 18.

It should be noted that the upper surface of the roll loading bed 20 of said lifter 18 is designed to be approximately flush with the floor surface 29 at its lower limit to facilitate loading of the linerboard roll 2 at the stockyard.

FIG. 8 shows a second embodiment of the diameter detecting sensor 23, wherein there is provided a photoelectric sensor, which comprises a light emitting element 31 and a light receiving element 32 opposing each other with the linerboard roll 2 on the roll loading bed 20 inbetween, at the height correspond- ing to the minimum roll diameter of the liner- board roll 2 which can be chucked by the swing arms 3 and 4 only by turning them downward. The above sensor is used to detect the roll diameter of the linerboard roll 2 from the roll loading bed 20 when the lifter 18 is descended to the lower limit. For example, in a linerboard roll 2 which cannot be chucked by the swing arms 3 and 4 only by their downward movement, the radiation emitted from the light emitting element 31 to the light receiving element 32 may not be screened by the linerboard roll 2, thus it will be detected that the linerboard roll 2 has a small diameter which requires to be lifted up by the lifter 18.

Fig. 9 shows a third embodiment of the diameter detecting sensor 23, wherein a reflection type photoelectric sensor 33 is used as the diameter detecting sensor 23. The reflection type photoelectric sensor 33 has a built-in light emitting element and light receiving element; said light emitting element is adopted to project light toward the linerboard roll 2 and the light receiving element is adopted to receive the reflection light reflected from said roll 2. Accordingly, the amount of the light reflected from the linerboard roll 2 received by the light receiving element varies depending on the distance between the reflec- tion type photoelectric sensor 33 and the surface of the linerboard roll 2. In other words, since the linerboard roll 2 is usually detected for the roll diameter at a predetermined position in a state that it is loaded on the roll loading bed 20, the distance between the reflection type photoelectric sensor 33 and the surface of the linerboard roll 2 varies depending on the diameter of the linerboard roll 2, and thereby the amount of light to be received by the light receiving element may be varied. As a result, the roll diameter of the linerboard roll 2 is detected according to the variation in the amount of light to be received by the light receiving element of the reflection type sensor 33. When the detected value is within the predetermined value, the linerboard roll 2 is lifted up by the lifter 18 to achieve mounting to the mill roll stand 1 in the same manner as mentioned above.

FIG. 10 shows a fourth embodiment of the diameter detecting sensor 23, wherein an image camera 34 for viewing the linerboard roll 2 on the roll loading bed 20 is used. Around the image camera 34, light sources 36 having a reflector 35 are arranged such that they can provide a clear view for the image camera 34. The image camera 34 is preliminarily focused on the linerboard roll 2 to be measured and designed to detect the roll diameter of the linerboard roll 2 automatically from a series of output signals obtained through horizontal scanning for viewing the linerboard roll 2, i.e. from the proportion of the linerboard roll 2 occupying the scene viewed by the image camera 34. As described above, when it is I; GB2195322A 5 detected that the value obtained from the above detection is below the predetermined value, the linerboard roll 2 is automatically lifted up by the lifter 18 to achieve chucking by the swing arms 3 and 4 of the mill roll stand 1.

EFFECT OF THE INVENTION As described above, according to the liner- board roll mounting device in a corrugator of this invention, it will be understood that with respect to a linerboard roll which has been determined to have a too small diameter to achieve chucking by the swing arms of the mill roll stand only by their rocking movement as a result of the roll diameter detection by the sensor, said linerboard roll is lifted up by the lifter to align the paper tube of the linerboard roll with the center blocks, thereby to effect automatic chucking of said linerboard roll. Thus, according to this invention, operator's burden will be reduced, as well as working efficiency may be improved.

Claims (2)

1. A linerboard roll mounting device for in a corrugator which produces the desired corrugated board sheets, in which device swing arms supported on a mill roll stand such that they can be rocked around a shaft are adopted to chuck removably a linerboard roll which feeds a linerboard sheet to be proceed in said corrugator, comprising:

a conveyor means which travels reciproca- tingly between a stockyard, where linerboard rolls are stored and are to be supplied, and a mill roll stand; tance from the emitter to the external surface of the linerboard roll and calculate the roll diameter of said linerboard roll.

3. A linerboard roll mounting device accord- ing to Claim 1, wherein said diameter detecting sensor comprises a light emitting element and a light receiving element which are arranged to oppose each other such that the optical axes thereof may meet when the roll diameter of the linerboard roll on a roll loading bed of the lifter positioned at its lower limit is the minimum diameter, with which chucking by the swing arms only by their downward movement is feasible.

4. A linerboard roll mounting device accord- ing to Claim 1, wherein said diameter detect ing sensor comprises a reflection type photo electric sensor having a built-in light emitting element and light receiving element; the light receiving element being designed to received a light having been projected toward the liner board roll and reflected from the surface thereof.

5. A linerboard roll mounting device accord ing to Claim 1, wherein said diameter detect ing sensor comprises an image camera for viewing the linerboard roll on the roll loading bed and is designed to detect the roll dia meter of said linerboard roll automatically from a series of output signals obtained through horizontal scanning for viewing the linerboard roll, i.e. from the proportion of the cardboard roll occupying the Scene viewed by the image camera.

5. A linerboard roll mounting device sub stantially as hereinbefore described with refer ence to, and as illustrated in, Figs. 1-7, a lifter provided on said conveyor means, Figs. 1-7 as modified in any of Figs. 8-10, capable of loading the linerboard roll and also of the accompanying drawings.

ascending or descending below the rocking lo- 105 6. A corrugator having a linerboard roll as cus of the swing arms of the mill roll stand; sembly device as claimed in any preceding and a diameter detecting sensor for detecting the roll diameter of the incoming linerboard roll loaded on said lifter, provided in relation with the linerboard roll mounting device; wherein the lifter of the conveyor means is lifted up to a required level to allow alignment of the paper tube in the linerboard roll loaded on said lifter with the tip of the center blocks provided in the swing arms, when the roll dia meter of the linerboard roll detected by the diameter detecting sensor is below a predeter mined value; and the lifter of the conveyor means is kept inoperative when the roll dia meter!of the linerboard roll detected by the diameter detecting sensor is above the predet ermined value.

2. A linerboard roll mounting device accord ing to Claim 1, wherein said diameter detect ing sensor comprising a sensor utilizing ultra sonic wave and is designed to receive an ul trasonic wave having been emitted by an emitter toward the linerboard roll and reflected from the surface thereof to determine the dis- Claim.

Published 19BB at The Patent Office, State House, 66/71 High Holborn, London WC 1 R 4TP. Further copies may be obtained from The Patent Office, Sales Branch, St Mary Cray, Orpington, Kent BR5 3RD. Printed by Burgess & Son (Abingdon) Ltd. Con. 1/87.