GB2281922A - Apparatus for producing single-faced corrugated board sheets - Google Patents

Description

-1 I 2281922 APPARATUS FOR PRODUCING SINGLE-FACED CORRUGATED BOARD SHEETS

BACKGROUND OF THE INVENTION

Field of the Invention

This invention relates to an apparatus for producing a single-faced corrugated board sheet by bringing a corrugating medium into press contact with a liner between the lower fluted roll and an endless belt to paste them together.

Description of the Related Art

In an apparatus for producing a single-faced corrugated board sheet (so-called single facer), an upper fluted roll and a lower fluted roll each having flutes formed on the circumference are rotatably supported between frames in a vertical relationship in such a way that they may engage with each other by their flutes, and a press roll is designed to be brought into press contact with the lower fluted roll via the corrugating medium and the liner which are the webs of the single-faced corrugated board sheet.

Namely, the corrugating medium is allowed to have a predetermined corrugation (flutes) as it is fed between the upper fluted roll and the lower fluted roll A starchy glue is applied to the crests of corrugation by a gluing roll provided in a gluing mechanism Meanwhile, the liner being fed from the side opposite to the corrugating medium via the press roll is pressed against the glued crests of the corrugating medium between the press roll and the lower fluted roll to be pasted together to form a single-faced corrugated board sheet.

The press roll employed in the conventional single facer is of a large-diameter metallic roll which is normally urged toward the lower fluted roll so as to apply a predetermined nip pressure to the corrugating medium and the liner passing between these rolls Since flutes consisting of continuous alternative repetition of crests and troughs are formed at a predetermined pitch on the circumference of the lower fluted roll, the rotation center of the lower fluted roll and that of the press roll shift slightly as the point of press contact therebetween shifts from the trough to the crest or vice versa Thus, as the result that the rotation centers of these rolls make cyclic reciprocating motions to be closer to or farther from each other as they rotate, great vibration and big noise are generated during formation of the single-faced corrugated board, causing the working environment in the plant to be worsened considerably Besides, since both the press roll and the lower fluted roll are made of rigid metallic materials, an impact is periodically applied to the press roll (so-called the hammer phenomenon) every time the crests of the lower fluted roll are abutted against the press roll.

Accordingly, linear press marks are formed horizontally on the surface of the liner in the thus formed single-faced corrugated board sheet corresponding to the pitch of the crests of the lower fluted roll, disadvantageously.

A means for coping with these problems described above is proposed, in which the press roll which is of a metallic roll is replaced by an endless belt so as to nip the corrugating medium and the liner between the endless belt and the lower fluted roll More specifically, an endless belt extended over a plurality of rolls is disposed, to be able to run freely thereon, at a position adjacent to the lower fluted roll, and the endless belt is brought closer to the outer surface of the lower fluted roll so as to nip the corrugating medium and the liner passing between the lower fluted roll and to paste them together In the case 3 - where such endless belt is employed, not only generation of great vibration and big noise can be controlled, but also press marks are prevented from being formed on the single- faced corrugated board sheet.

Since a plurality of rolls and an endless belt are disposed adjacent to the lower fluted roll in the single facer employing such endless belt, operators must carry out replacement or maintenance of the lower fluted roll in a narrow space, forcing them time-consuming and intricate operations Besides, the replacement and maintenance of the lower fluted roll itself also require intricate procedures.

Further, while a tension sufficient to nip the corrugating medium and the liner between the endless belt and the lower fluted roll may be applied to the endless belt extended over the group of rolls only when the single facer is in operation, the endless belt is conventionally maintained in a state where a constant tension is always applied thereto, even when the corrugating medium and liner are guided into the single facer or during replacement or maintenance of the lower fluted roll, so that the endless belt degrades soon to have a shortened life, disadvantageously.

Meanwhile, since the endless belt and the lower fluted roll must be abutted against each other parallelwise over the full length (in the axial direction of the roll) in the single facer described above, it is impossible to form crowns on the rolls over which the belt is extended.

However, it is extremely difficult to form an endless belt having a uniform thickness and a uniform inner peripheral size over the full width thereof, and most of such belts involve minor errors Accordingly, such endless belt extended over the group of uncrowned rolls tends to undergo widthwise biasing or meandering due to the errors inherent 4 - in itself to be displaced from the zone where the corrugating medium and the liner are pasted together, causing defective pasting therebetween.

Under such circumstances, it is proposed to prevent meandering of the endless belt extended over the group of rolls by shifting the axes of these rolls to slightly cross each other However, since the directions of meandering, the strokes thereof, etc due to the errors and the like inherent in the endless belts vary one by one, the direction and the amount of shifting these rolls must be adjusted every time the belt is replaced Namely, each roll must be provided with an adjusting mechanism, making the structure of the single facer complicated and also leading to cost elevation, disadvantageously Further, it can be pointed out that the spaces for disposing the respective adjusting mechanisms must be secured, and thus the size of the single facer is enlarged Besides, adjusting operations are required every time the endless belt is replaced to increase the loss time, causing reduction of production efficiency.

In order to nip the corrugating medium and the liner between the endless belt and the lower fluted roll to securely paste them together in the application mechanism equipped with such endless belt, the following means must be provided:

( 1) a means for running the endless belt at a speed synchronous with the circumferential speed of the lower fluted roll; ( 2) a means for heating the liner to impart heat to the to-be-glued portions to accelerate gelation of a starch glue; and ( 3) a means for applying a predetermined tension to the endless belt so as to nip the corrugating medium and the liner between the endless belt and the lower fluted roll with a predetermined nip pressure Namely, a proposal of an application mechanism in which the means ( 1), ( 2) and ( 3) are minimized is desired.

This invention is proposed in view of the problems inherent in the single facers of the prior art described above and in order to solve them successfully, and it is a first object of the invention to provide a single facer which allows easy replacement and maintenance of the fluted roll and the endless belt.

It is a second object of the invention to provide a single facer in which meandering of the endless belt is prevented using a simple structure and at a low cost.

It is a third object of the invention to provide a single facer in which the application mechanism can be minimized by imparting required functions to the respective rolls on which the endless belt is extended.

SUMMARY OF THE INVENTION

In order to solve the above problems and attain the first object of the invention successfully, there is provided a single facer consisting of an upper fluted roll having flutes formed on the circumference thereof; a lower fluted roll, also having on the circumference thereof flutes which are engaged with those of the upper fluted roll and form a predetermined corrugation on a corrugating medium fed between the upper fluted roll and the lower fluted roll; a gluing mechanism for gluing the crests of corrugation in the corrugating medium; and an application mechanism which is disposed adjacent to the lower fluted roll and equipped with an endless belt extended over a plurality of rolls so as to be able to run freely thereby; in which the liner is pressed against the glued crests of corrugation of the corrugating medium to paste the liner with the corrugating medium and form a single-faced corrugated board sheet; characterized in that a movable body is disposed to be able to move closer to or farther from the main body in which the upper fluted roll and the lower fluted roll are disposed; the application mechanism being disposed in the movable body; wherein the endless belt of the application mechanism is designed to be pressed against the lower fluted roll via the corrugating medium and the liner by moving the movable body closer to the main body.

Meanwhile, according to another aspect of the invention for attaining the first object successfully, there is provided a single facer, wherein the application mechanism is provided with a tension roll which can apply or release tension to and from the endless belt extended over a group of rolls According to another aspect of the invention for solving the above problems and attaining the second object successfully, there is provided a single facer consisting of an upper fluted roll having flutes formed on the circumference thereof; a lower fluted roll, also having on the circumference thereof flutes which are engaged with those of the upper fluted roll and form a predetermined corrugation on a corrugating medium passed between the upper fluted roll and the lower fluted roll; a gluing mechanism for gluing the crests of corrugation in the corrugating medium; and an application mechanism which is disposed adjacent to the lower fluted roll and equipped with an endless belt extended over a plurality of rolls so as to be able to run freely thereby; in which a liner is pressed against the glued crests of corrugation of the corrugating medium fed along the circumference of the lower fluted roll to be pasted with the corrugating medium and form a single-faced corrugated board sheet; characterized in that a pair of regulating means are disposed on at least one of a plurality of rolls, over which the endless belt is extended, to be spaced from each other in the direction orthogonal to the running direction of the endless belt, and that the endless belt is designed to run between the regulating means, According to another aspect of the invention for solving the above problems and attaining the third object of the invention, there is provided a single facer consisting of an upper fluted roll having flutes formed on the circumference thereof; a lower fluted roll, also having on the circumference thereof flutes which are engaged with those of the upper fluted roll and form a predetermined corrugation on a corrugating medium fed between the upper fluted roll and the lower fluted roll; a gluing mechanism for gluing the crests of corrugation in the corrugating medium; and an application mechanism equipped with an endless belt which is driven to run adjacent to the lower fluted roll; in which the liner is pressed against the glued crests of corrugation of the corrugating medium fed along the circumference of the lower fluted roll to be pasted with the corrugating medium and form a single-faced corrugated board sheet; characterized in that the application mechanism is provided with a drive roll which is driven to be rotated by a suitable drive source, a preheating roll into which a high-temperature steam is distributed, and a tension roll which can apply tension to the endless belt; the endless belt being extended over the three rolls.

BRIEF DESCRIPTION OF THE DRAWINGS

The features of this invention that are believed to be novel are set forth with particularity in the appended claims The invention, together with the objects and advantages thereof, may best be understood by reference to the following description of the preferred embodiment taken in conjunction with the accompanying drawings in which:

Fig 1 shows schematically a cross-sectional view of the single facer according to a preferred embodiment of the invention; Fig 2 shows schematically a front view of the single facer according to the preferred embodiment of the invention; Fig 3 shows schematically the major section of the single facer according to the preferred embodiment of the invention; Fig 4 shows in expanded side view the three rolls disposed on split frames of the single facer according to the preferred embodiment of the invention; Fig 5 shows in cross-section a guide roll in the single facer according to the preferred embodiment of the invention; Fig 6 is a view explaining the state where a movable body in the single facer according to the preferred embodiment of the invention is moved to a second retracted position to separate the split frames and auxiliary frames from main frames; Fig 7 shows schematically in cross section an adjusting mechanism for a seal roll in the single facer according to the preferred embodiment of-the invention; 9 - Fig 8 shows schematically in cross section the adjusting mechanism for a seal roll in the single facer according to the preferred embodiment of the invention; and Fig 9 is a view illustrating a variation of the application mechanism in the single facer according to the preferred embodiment of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The single facer according to this invention will now be described by way of a preferred embodiment referring to the attached drawings Fig 1 shows schematically the constitution of the single facer according to the preferred embodiment of the invention, in which a main body 14 of the single facer, consisting of a pair of opposing fixed frames 12 arranged to be spaced from each other (one on the drive side and the other on the operation side) on the line orthogonal to the direction of feeding a corrugating medium 20), is disposed on a base 10 installed on the floor of a plant, and an upper fluted roll 16 having flutes formed on the circumference thereof and a lower fluted roll 18 also having flutes formed on the circumference thereof are rotatably supported between these frames 12 The rotary shaft of the upper fluted roll 16 locates diagonally above that of the lower fluted roll 18, and the flutes of the upper fluted roll 16 are designed to be engageable with those of the lower fluted roll 18 via the corrugating medium 20 Meanwhile, a gluing mechanism 26 consisting of a gluing roll 22 and a doctor roll 24 is disposed immediately below the upper fluted roll 16 and diagonally below the lower fluted roll 18 The corrugating medium 20 is fed from a web feeding source (not shown) which is assumed to locate on the left side in Fig 1 via a plurality of guide rolls 28 to the engagement zone defined between the upper fluted roll 16 and the lower fluted roll - 18 to be provided with a predetermined corrugation by passing the engagement zone The thus corrugated corrugating medium 20 is glued at the crests by the gluing mechanism 26 and then forwarded along the circumference of the lower fluted roll 18 to be diverted upward.

It should be noted here that a pressure chamber 30, in which the gluing mechanism 26 is to be housed, is defined immediately below the upper fluted roll 16 and diagonally below the lower fluted roll 18 The pressure chamber 30 is open toward the upper fluted roll 16 and the lower fluted roll 18 As shown in Fig 3, sealing members 34 are interposed between the opening of the pressure chamber 30 and the upper and lower fluted rolls 16,18 along the axes thereof, respectively, so that the pressure chamber 30 may be maintained substantially air tight A compressed air is fed from a source (not shown) to the pressure chamber 30 so as to maintain the inside of the chamber to be slightly higher than the atmospheric pressure (e g by 0 15 atm).

In this case, the outer circumference of the lower fluted roll 18 facing the pressure chamber 30 is assuming the atmospheric pressure by virtue of the circumferential grooves defined axially at predetermined intervals.

Accordingly, the corrugating medium 20 corrugated by passing between the upper fluted roll 16 and the lower fluted roll 18 can be fed stably as pressed against the roll surface due to the difference between the pressure in the pressure chamber 30 and that on the circumference of the lower fluted roll 18.

Incidentally, the gluing mechanism 26 is disposed to be slidable along the rails 36 laid on the bottom (base 10) of the pressure chamber 30, so that the gluing mechanism 26 can be carried out from the pressure chamber 30 along the rails 36 by opening the door 38 disposed on the left side of the pressure chamber 30 shown in Fig 1.

11 - A pair of guide rails 40 spaced from each other on the drive side and the operation side are laid on the base 10 at the portion extending rightward (at the position closer to the lower fluted roll 18) than the location of the main body 14, as shown in Fig 1, and a movable body 44 is disposed on these guide rails 40 to be slidable via corresponding sliders 42 The movable body 44 consists of a pair of inverted substantially L-shaped main frames 46, a pair of split frames 50 and a pair of auxiliary frames 52, which are fixed by a plurality of bolts 48 to the main frames 46, respectively Namely, the main frames 46 oppose to be spaced from each other on the drive side and the operation side with a predetermined distance therebetween, and a pair of sliders 42 are disposed on the lower surfaces of the frames 46, respectively, with preheaters 64 (to be described later) being disposed between these main frames 46 Each main frame 46 is notched on the side facing the main body 14 of the single facer, and the triangular split frame 50 is fastened onto the notch with bolts Meanwhile, the auxiliary frames 52 having a wedge-like form are interposed into the clearances defined between the split frames 50 and the main frames 46 and fastened with bolts onto the main frames 46, respectively An application mechanism 54 (to be described later) is interposed between the opposing split frames 50, while a guide roll 78 (to be described later) is disposed between the auxiliary frames 52 (see Figs 4 and 5).

As shown in Fig 2, a pair of hydraulic cylinders 56 (only one cylinder is shown) is disposed on the base 10 on the outer sides of the main frames 46, and the piston rod 56 a of each hydraulic cylinder 56 is connected to the bracket 58 disposed to the corresponding main frame 46.

Accordingly, if these hydraulic cylinders 56 are synchronously operated in the positive or negative 12 - direction, the movable body 44 can be moved along the guide rails 40 to be closer to or farther from the main body 14.

Stoppers 60 protrude from those front end faces of the respective main frames 46 which face the fixed frames 12, so that the movable body 44 may be located at the operation position (the position where the endless belt 74 of the application mechanism 54 is abutted against the lower fluted roll 18) by bringing these stoppers 60 into abutment against the positioning members 62 disposed to the corresponding fixed frames 12 Incidentally, the positions of the positioning members 62 are adapted to be adjustable, so that the operation position of the movable body 44 can suitably be adjusted.

The hydraulic cylinders 56 are designed to be able to position the movable body 44 at three positions: the operation position (as indicated by the solid line in Fig.

2) where the stoppers 60 are abutted against the positioning members 62; a first retracted position (as indicated by the dotted-and-dashed line in Fig 2) where the movable body 44 is spaced from the main body 14 to allow replacement and maintenance of the lower fluted roll 18; and a second retracted position (see Fig 6) where the movable body 44 is spaced from the main body 14 by the required distance so as to allow replacement of the endless belt 74 in the application mechanism 54 Incidentally, when the movable body 44 is positioned at the operation position, the movable body 44 is designed to be prevented from moving apart from the operation position under urging of the stoppers 60 by the hydraulic cylinders 56 such that they may be abutted against the positioning members 62 with a required pressure.

A couple of roll-like preheaters 64 are disposed between the main frames 46, as shown in Fig 3 The liner 66 fed from a web feeding source (not shown) assumed to be 13 - disposed on the right side in Fig 3 is fed via the preheaters 64 to the lower fluted roll 18 to be pasted with the corrugating medium 20 at the glued crests and fed upward.

The application mechanism 54 for pasting the corrugating medium 20 with the liner 66 in cooperation with the lower fluted roll 18 is disposed between the split frames 50.

Namely, a drive roll 68 and a preheating roll 70 are rotatably supported between the split frames 50 on the side closer to the lower fluted roll 18 and spaced from each other along the tangential line of the lower fluted roll 18, as shown in Fig 3 A tension roll 72 is also rotatably supported between the split frames 50 on the side farther from the lower fluted roll 18, and the endless belt 74 is extended over these three rolls 68, 70 and 72 all supported between the split frames 50 The portion of the endless belt 74 locating between the drive roll 68 and the preheating roll 70 is designed to approach the circumference of the lower fluted roll 18, when the movable body 44 is moved closer to the main body 14 and positioned at the operation position, to nip the corrugating medium 20 being fed along the circumference of the lower fluted roll 18 and the liner 66 to be pasted therewith in cooperation with the lower fluted roll 18, and thus they are pasted together between that portion of the endless belt 74 and the lower fluted roll 18 Incidentally, the liner 66 fed over the preheaters 64 is carried by the endless belt 74 along the circumference of the preheating roll 70 to the abutment section where it is abutted against the lower fluted roll 18 via the endless belt 74.

When the movable body 44 is positioned at the operation position, the preheating roll 70 locating between the seal roll 32 and the lower fluted roll is abutted against them via the endless belt 74 Thus, the opening of the pressure 14 - chamber 30 is blocked by the upper fluted roll 16, lower fluted roll 18, preheating roll 70 and the seal roll 32.

Incidentally, a seamless resin belt is preferably used as the endless belt 74 Since the seal roll 32 and the preheating roll 70 are abutted against each other via the endless belt 74, gaps corresponding to the thickness of the belt 74 are formed between these two rolls 32,70 at the respective axial end portions thereof where the belt 74 is not present Since a compressed air is designed to be supplied constantly to the pressure chamber 30 so as to maintain a predetermined air pressure therein in view of leakage of the compressed air from the chamber 30, a great leakage of the compressed air through these gaps between these rolls 32,70 tends to cause elevation of the running cost due to the increased feed of the compressed air or reduction of air pressure in the chamber 30, resulting in the failure of securely press-contacting the corrugating medium 20 with the lower fluted roll 18 Therefore, it is recommended to fit sleeves which is as thick as the endless belt 74 on both end portions of the seal roll 32 so as not to form gaps between the seal roll 32 and the preheating roll 70 Incidentally, a U-shaped groove which is as wide as the endless belt 74 may otherwise be formed on the circumference of the seal roll 32 These sleeves or the groove also serves to regulate meandering (biasing in the axial direction of the roll) of the endless belt 74.

The tension of the endless belt 74 is designed to be adjustable such that it can press the corrugating medium 20 fed along the circumference of the lower fluted roll 18 and the liner 66 to be pasted therewith with an optimum contact pressure Namely, supporting members 73 disposed to both axial end portions of the tension roll 72 are slidably fitted in the slots 50 a defined in the respective split frames 50, so that the tension roll 72 may be movable with respect to the split frames 50 in the radial direction of - the lower fluted roll 18 Meanwhile, a couple of hydraulic cylinders 76 are disposed on the outer sides of the split frames 50, with the piston rods thereof being connected to the corresponding supporting members 73 Accordingly, the tension roll 72 can be moved closer to or farther from the endless belt 74 by operating the pair of hydraulic cylinders 76 synchronously in the positive or negative direction, and thus the tension to be applied to the belt 74 can be adjusted Incidentally, in the hydraulic cylinders 76 in this embodiment, the relative position of the tension roll 72 with respect to the endless belt 74 is designed to be shifted between three positions: a first position where a predetermined tension is applied to the endless belt 74 to achieve pasting of the corrugating medium 20 with the liner 66 securely; a second position where a very small tension is applied to the endless belt 74 extended over the three rolls 68,70,72 to be slackless; and a third position where the endless belt 74 is slackened enough to be pulled out axially from these three rolls 68,70,72.

The outer peripheral size of each split frame 50 is designed to be smaller than the inner peripheral size of the endless belt 74, as shown in Fig 6 Namely, after the tension roll 72 is located at the third position to slacken the endless belt 74, the endless belt 74 extended over the three rolls 68,70,72 can axially be pulled out without separating the split frames 50 therefrom Accordingly, the cycle time required for the replacement of the endless belt 74 can be reduced to improve production efficiency.

The drive roll 68 supported between the split frames 50 is connected to a drive source (not shown) of the single facer via a universal joint 82, as shown in Fig 4, to be rotated thereby, so as to drive the endless belt 74 to run at a predetermined speed synchronously with the upper fluted 16 roll 16 and the lower fluted roll 18 It should be noted here that, since the drive roll 68 and the drive source are connected by the universal joint 82, the movable body 44 is allowed to be shifted closer to or farther from the main body 14 Meanwhile, the preheating roll 70 is connected to a high-temperature steam source (not shown), which distributes a high-temperature steam into the roll so as to heat the roll surface to a predetermined temperature The liner 66 is heated via the endless belt 74 extended over the preheating roll 70 to apply heat to the glued portions and accelerate gelation of the starchy glue so that it can securely be bonded with the corrugating medium 20.

A pair of regulating members 80 are fitted on the circumference of the tension roll 72 to be spaced from each other by the distance slightly longer than the width of the endless belt 74 and arranged on a line orthogonal to the running direction of the endless belt 74, as shown in Fig.

4 These regulating members 80 serve to prevent widthwise biasing (meandering) of the endless belt 74 More specifically, while the endless belt 74 running on the tension roll 72 between these regulating members 80 undergoes widthwise meandering due to the errors etc.

inherent in the belt itself, as described above, the regulating members 80 prevent such biasing of the belt 74, because each side of the belt 74 is abutted against the corresponding regulating member 80 Thus, the endless belt 74 is prevented from slipping out of the bonding zone (the zone along the width of the corrugating medium 20 and that of the liner 66) where thecorrugating medium 20 and the liner 66 are pasted together, enabling secured bonding therebetween Incidentally, each regulating member 80 consists of a split member, which can be separated into two parts and which can be fixed onto the circumference of the tension roll 72 by immobilizing them to each other.

17 - A guide roll 78 is rotatably supported between the auxiliary frames 52 to be parallel to the three rolls 68,70,72 over which the endless belt 74 is extended The guide roll 78 locates outer than the portion of the endless belt 74 locating between the drive roll 68 and the tension roll 72 A pair of regulating members 80 are fitted on the circumference of this guide roll 78 to be spaced from each other by the distance slightly longer than the width of the endless belt 74, as shown in Fig 5 The guide roll 78 is positioned outer than the endless belt 74 such that the circumference of the roll 78 can be abutted against the endless belt 74 outside Accordingly, these regulating members 80 serve to prevent widthwise meandering of the endless belt 74.

Each of the auxiliary frames 52 is interposed into the clearance formed between the corresponding main frame 46 and the split frame 50 attached thereto and serves to carry out positioning of the triangular split frame 50 The split frame 50 is designed to be separated from the main frame 46 by separating first the auxiliary frame 52 therefrom and lifting the split frame 50 substantially upward with respect to the main frame 46 (see Fig 6).

Thus, the distance (second retracted position) that the movable body 44 is to be moved away from the main body 14 at the replacement of the endless belt 74 can be designed to be smaller Further, the split frame 50 itself can be downsized.

The position of the seal roll 32 is designed to be adjusted to be closer to or farther from the preheating roll 70 by the adjusting mechanisms disposed to the axial end portions of the seal roll 32, as shown in Figs 7 and 8 Since these adjusting mechanisms are of the same constitution, only one mechanism will be described Namely, Fig 7 shows the adjusting mechanism disposed on the drive side of the 18 - seal roll 32, in which a supporting member 84 having an vertically elongated opening 84 a stands on the base 10 A holder 86 fitted on the shaft 32 a of the seal roll 32 is fitted in this elongated opening 84 a to be ascendable therein The holder 86 has a bevel 86 a sloping at a required angle on the lower surface thereof, as shown in Fig 7 A hydraulic cylinder 88 is disposed via a bracket to the base 10 on the main body side, and a wedge 92 having on the upper surface a bevel 92 a corresponding to the bevel 86 a of the holder 86 is connected to the piston rod 88 a of the cylinder 88 As shown in Fig 8, the wedge 92 is slidably fitted in the elongated opening 84 a of the supporting member 84, so that the bevel 86 a on the lower surface of the holder 86 may be abutted against the bevel 92 a on the upper surface of the wedge 92 Accordingly, the seal roll 32 can be moved upward or downward by operating the hydraulic cylinders 88 of the respective adjusting mechanisms in the positive or negative direction to advance or retract the wedges 92 under engagement of these bevels 86 a and 92 a, and thus the clearance between the seal roll 32 and the preheating roll 70 can be adjusted.

Next, the function of the single facer according to the above-described embodiment will be described It should be appreciated that the movable body 44 is located at the first retracted position and the tension roll 72 at the second position.

In producing a single-faced corrugated board sheet, when the hydraulic cylinders 56 are operated in the required direction, the movable body 44 located at the first retracted position is moved closer to the main body 14 along the guide rails 40 and located at the operation position where the stoppers 60 are abutted against the positioning members 62 Thus, the endless belt 74 in the application mechanism 54 disposed between the split frames 19 - is moved closer to the lower fluted roll 18 disposed in the main body 14 In this state, the hydraulic cylinders 76 are operated in the required direction to move the tension roll 72 located at the second position to the first position to apply a required tension to the endless belt 74 Namely, as shown in Fig 3, the corrugating medium 20 and the liner 66 fed along the circumference of the lower fluted roll 18 can be pressed against the roll surface by the portion of the endless belt 74 locating between the drive roll 68 and the preheating roll 70 It should be noted here that the movable body 44 locating at the operation position is urged constantly toward the main body 14 with a predetermined pressure by the hydraulic cylinders 56, so that the movable body 44 is prevented from being moved apart from the operation position by the load applied to the application mechanism 54 during the formation of single-faced corrugated board sheets.

The corrugating medium 20, forwarded via the plurality of guide rolls 28 from the web feeding source to the engagement zone defined between the upper fluted roll 16 and the lower fluted roll 18 under the state where the upper fluted roll 16 and the lower fluted roll 18 are driven to rotate and the drive roll 68 is also rotated so as to drive the endless belt 74, is allowed to have a predetermined corrugation by passing the zone The thus corrugated corrugating medium 20 is glued at the crests by the gluing mechanism 26 and then fed along the circumference of the lower fluted roll 18 to be diverted upward Incidentally, the corrugated corrugating medium 20 can stably be fed on as pressed on the circumference of the lower fluted roll 18 with the aid of the pressure secured in the pressure chamber 30.

Meanwhile, the liner 66 fed from the web feeding source via the preheaters 64 is forwarded via the endless belt 74 - along the circumference of the preheating roll 70 toward the bonding zone, where it is pasted with the corrugating medium 20 The liner 66 is pressed against the crests of the corrugating medium 20 between the endless belt 74 and the lower fluted roll 18 over a predetermined length to be pasted with the corrugating medium 20, and thus a single- faced corrugated board sheet can be formed In this process, since a high-temperature steam is distributed into the preheating roll 70 to heat the roll surface to a predetermined temperature, the liner 66 can be heated via the endless belt 74 extended over the preheating roll 70 to apply heat to the glued portions of the corrugating medium and accelerate gelation of the starchy glue, enabling secured bonding of the liner 66 with the corrugating medium 20.

As shown in Figs 4 and 5, the endless belt 74 is adapted to run between the regulating members 80 disposed on the tension roll 72 and those disposed on the guide roll 78, the possible meandering attributable to the errors inherent in the belt 74 can be prevented by these regulating members Accordingly, the endless belt 74 can constantly be maintained to run in the bonding zone where the corrugating medium 20 is pasted with the liner 66, and thus they can securely be pasted together Besides, since the mechanism of preventing meandering of the endless belt 74 is of such a simple structure as to fit the regulating members 80 onto the rolls 72,78, neither the cost nor the size of the single facer is increased.

In the replacement, maintenance, etc of the lower fluted roll 18, the hydraulic cylinders 56 are operated in the negative direction to move the movable body 44 to be farther from the main body 14 to the first retracted position, as indicated by the dotted-and-dashed line in Fig 2 Thus, a necessary clearance can be secured between 21 - the lower fluted roll 18 and the application mechanism 54, and the operator can carry out replacement or maintenance of the roll 18 easily in a wide space Meanwhile, the tension roll 72 of the application mechanism 54 is moved to the intermediate second position by operating the hydraulic cylinders 76 to release the tension applied to the endless belt 74 extended over the three rolls 68,70,72 Since the endless belt 74 can be maintained substantially tensionless when the single facer is not in operation, the life of the belt 74 can be extended.

Next, replacement of the endless belt 74 in the application mechanism 54 will be described Since the endless belt 74 employed according to this embodiment is seamless, it must be pulled out axially from the three rolls 68,70,72.

Accordingly, after the movable body 44 is moved to the second retracted position which is the farthest from the main body 14, the auxiliary frames 52 are first separated from the main frames 46 Then, the split frames 50 are separated from the main frames 46, as shown in Fig 6, and they are carried by an overhead travelling crane to the replacement position, where the hydraulic cylinders 76 are operated to retract the tension roll 72 to be located at the third position, and thus the endless belt 74 can be slackened enough to be pulled out from the rolls 68,70,72.

The regulating members 80 fitted on the tension roll 72 are designed to have dimensions to allow easy pulling out of the endless belt 74, when the tension roll 72 is located at the third position Besides, the outer peripheral size of each split frame 50 is designed to be smaller than the inner peripheral size of the endless belt 74, so that the endless belt 74 can easily be pulled out axially from the three rolls 68,70,72 without separating the split frames 50 therefrom and replaced easily with a new belt.

The split frames 50 in which the application mechanism 54 22 - with new endless belt 74 is disposed is carried by the overhead travelling crane to a position above the main frames 46 and unloaded onto the fixed positions of the main frames 46, and they are fastened with bolts 48.

Subsequently, the auxiliary frames 52 are interposed between the main frames 46 and the split frames 50 and fastened with bolts 48, respectively, and thus the split frames can stably be immobilized at predetermined positions of the main frames 46 The meandering direction, meandering stroke, etc of the new endless belt 74 are different from those of the previous endless belt 74.

However, because of the constitution in which the regulating members 80 for regulating meandering of the endless belt 74 are fitted on the rolls 72,78, it is not necessary to make adjustment of the rolls 72,78 or the regulating members 80 Accordingly, the cycle time can be reduced to improve production efficiency.

Incidentally, it is also possible to provide spare split frames 50 having the application mechanism 54 to which a new endless belt 74 is attached beforehand and maintenance of which has been completed, and to fit such spare split frames 50 to the main frames 46 immediately after the split frames 50, in which the application mechanism 54 to be subjected to maintenance service is disposed, are separated from the main frames 46 In this case, the time required for the replacement of the endless belt 74, the maintenance of the application mechanism 54, etc can notably be reduced.

In the constitution employed in the embodiment shown in Fig 1, the endless belt 74 in the application mechanism 54 is extended over the three rolls 68,70,72, and the tension roll 72 locating inner than the endless belt 74 is adapted to be moved closer to or farther from the endless belt 74.

However, the present invention is not limited to such 23 - constitution For example, as shown in the variation of Fig 9, the endless belt 74 may be extended over the drive roll 68 and the preheating roll 70, and the tension roll 72 locating opposite to the lower fluted roll 18 and outer than the endless belt 74 may be moved closer to or farther from the endless belt 74 so as to adjust the tension thereof Furthe r, in the variation shown in Fig 9, only the drive roll 68 and the preheating roll 70 may be disposed in the split frames 50 instead of disposing all of the three rolls 68,70,72 in the split frames 50, and the tension roll 72 can be disposed in the main frames 46 It is also possible to allow either the drive roll 68 or the preheating roll 70 disposed on the split frames 50 to function as the tension roll.

In the embodiment described above, the movable body 44 consists of the main frames 46, split frames 50 on which the application mechanism 54 is disposed and auxiliary frames 52 However, this invention is not limited to such constitution, and the movable body 44 may be allowed to consist of main frames 46 and split frames 50.

Alternatively, the regulating members 80 as disposed on the guide rolls 78 or the tension roll 72 may also be fitted on the drive roll 68 and the preheating roll 70.

In the embodiment described above, the regulating members are fitted on the tension roll 72 and the guide roll 78.

However, this invention is not limited to such constitution, and the regulating members 80 may be fitted onto the tension roll 72 only Alternatively, it is also possible to fit the regulating members onto one of the drive roll 68, preheating roll 70, tension roll 72 and guide roll 78, or to any arbitrary roll or rolls, or to all of the rolls Further, in the variation shown in Fig 9, the constitution of fitting the regulating members 80 can suitably be selected: to fit the regulating members 80 onto 24 - one of the rolls abutted against the endless belt 74, to any arbitrary number of such rolls, or to all of such rolls It is also possible to employ, in the constitution in which the endless belt is extended over two rolls and one of these rolls is allowed to function as the tension roll, a constitution in which the regulating members are disposed one or both of these rolls Still further, while in the embodiment described above, the regulating members are fitted onto the rolls as separate members, for example, a U-shaped groove having a width slightly greater than the width of the endless belt may, of course, be defined on the roll surface in place of fitting such independent regulating members, to allow the endless belt to run within the U-shaped groove and prevent meandering thereof by the side walls of the groove.

While in the constitution described in the above embodiment, the corrugating medium is pressed against the surface of the lower fluted roll with the aid of a pressurizing force, it is also possible to suitably employ a system for sucking the corrugating medium onto the roll surface by exerting a suction force from the lower fluted roll Meanwhile, as the means for moving the movable body, a mechanism consisting of a motor and a ball screw or other means may suitably be selected and employed in place of the hydraulic cylinders It should be apparent to those skilled in the art that the present invention may be embodied in many other specific forms without departing from the spirit or scope of the invention Therefore, the present embodiment as well as the variations thereof are to be considered as illustrative and not restrictive and the invention is not to be limited to the details given herein, but may be modified within the scope of the appended claims.

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Claims (12)

What is Claimed is:

1 A single facer consisting of an upper fluted roll ( 16) having flutes formed on the circumference thereof; a lower fluted roll ( 18), also having on the circumference thereof flutes which are engaged with those of said upper fluted roll ( 16) and form a predetermined corrugation on a corrugating medium ( 20) passed between said upper fluted roll ( 16) and said lower fluted roll ( 18); a gluing mechanism ( 26) for gluing the crests of corrugation in said corrugating medium ( 20); and an application mechanism ( 54) which is disposed adjacent to said lower fluted roll ( 18) and equipped with an endless belt ( 74) extended over a plurality of rolls so as to be able to run freely thereby; in which a liner ( 66) is pressed against the glued crests of corrugation of said corrugating medium ( 20) fed along the circumference of said lower fluted roll ( 18) to be pasted with said corrugating medium ( 20) and form a single- faced corrugated board sheet; characterized in that a movable body ( 44) is disposed to be able to move closer to or farther from said main body ( 14) in which said upper fluted roll ( 16) and said lower fluted roll ( 18) are disposed; said application mechanism ( 54) being disposed in said movable body ( 44); wherein said endless belt ( 74) of said-application mechanism ( 54) is designed to be pressed against said lower fluted roll ( 18) via said corrugating medium ( 20) and said liner ( 66) by moving said movable body ( 44) closer to said main body ( 14).

2 The single facer according to Claim 1, wherein said application mechanism ( 54) is provided with a tension roll ( 72) which can apply or release tension to and from said endless belt ( 74) extended over a group of rolls ( 68,70).

3 The single facer according to Claim 1 or 2, wherein 26 - said movable body ( 44), when moved closer to said main body ( 14) by a moving means ( 56), is abutted against a positioning means ( 62), the position of which being designed to be adjustable, to allow said endless belt ( 74) of said application mechanism ( 54) to locate at the operation position, where said endless belt ( 74) is pressed against said lower fluted roll ( 18); said movable body ( 44) being urged with a predetermined pressure by said moving means ( 56) to be abutted against said positioning means ( 62).

4 A single facer consisting of an upper fluted roll ( 16) having flutes formed on the circumference thereof; a lower fluted roll ( 18), also having on the circumference thereof flutes which are engaged with those of said upper fluted roll ( 16) and form a predetermined corrugation on a corrugating medium ( 20) passed between said upper fluted roll ( 16) and said lower fluted roll ( 18); a gluing mechanism ( 26) for gluing the crests of corrugation in said corrugating medium ( 20); and an application mechanism ( 54) which is disposed adjacent to said lower fluted roll ( 18) and equipped with an endless belt ( 74) extended over a plurality of rolls so as to be able to run freely thereby; in which a liner ( 66) is pressed against the glued crests of corrugation of said corrugating medium ( 20) fed along the circumference of said lower fluted roll ( 18) to be pasted with said corrugating medium ( 20) and form a single- faced corrugated board sheet; characterized in that a movable body ( 44) is disposed to be able to move closer to or farther from said main body ( 14) in which said upper fluted roll ( 16) and said lower fluted roll ( 18) are disposed, and that said movable body ( 44) consists of a plurality of separable frames ( 46,50); said application mechanism ( 54) being disposed in the split frames ( 50) which can be separated from the main frames ( 46) constituting said movable body ( 44).

27 - The single facer according to Claim 4, wherein the outer peripheral size of said split frames ( 50) in which said application mechanism ( 54) is disposed is designed to be smaller than the inner peripheral size of said endless belt ( 74) in said mechanism ( 54).

6 The single facer according to Claim 4 or 5, wherein said application mechanism ( 54) is provided with a tension roll ( 72) disposed movably on said split frames ( 50) inner than said endless belt ( 74) so as to be able to be abutted against said belt ( 74); said endless belt ( 74) extended over said group of rolls being designed to be slackened enough to be pulled out axially therefrom by moving said tension roll ( 72) away from said endless belt ( 74).

7 A single facer consisting of an upper fluted roll ( 16) having flutes formed on the circumference thereof; a lower fluted roll ( 18), also having on the circumference thereof flutes which are engaged with those of said upper fluted roll ( 16) and form a predetermined corrugation on a corrugating medium ( 20) passed between said upper fluted roll ( 16) and said lower fluted roll ( 18); a gluing mechanism ( 26) for gluing the crests of corrugation in said corrugating medium ( 20); and an application mechanism ( 54) which is disposed adjacent to said lower fluted roll ( 18) and equipped with an endless belt ( 74) extended over a plurality of rolls so as to be able to run freely thereby; in which a liner ( 66) is pressed against the glued crests of corrugation of said corrugating medium ( 20) fed along the circumference of said lower fluted roll ( 18) to be pasted with said corrugating medium ( 20) and form a single- faced corrugated board sheet; characterized in that a pair of regulating means ( 80) are disposed on at least one of a plurality of rolls ( 68,70,72), over which said endless belt ( 74) is extended, 28 - to be spaced from each other in the direction orthogonal to the running direction of said endless belt ( 74), and that said endless belt ( 74) is designed to run between said regulating means ( 80).

8 The single facer according to Claim 7, wherein one of said plurality of rolls ( 68,70,72) over which said endless belt ( 74) is extended is a tension roll for applying tension to said belt ( 74); said regulating means ( 80) being disposed on said tension roll ( 72).

9 The single facer according to Claim 7 or 8, wherein said regulating means ( 80) are provided on a guide roll ( 78) which is disposed outer than and adjacent to the running route of said endless belt ( 74) and abutted thereagainst.

A single facer consisting of an upper fluted roll ( 16) having flutes formed on the circumference thereof; a lower fluted roll ( 18), also having on the circumference thereof flutes which are engaged with those of said upper fluted roll ( 16) and form a predetermined corrugation on a corrugating medium ( 20) fed between said upper fluted roll ( 16) and said lower fluted roll ( 18); a gluing mechanism for gluing the crests of corrugation in said corrugating medium ( 20); and an application mechanism ( 54) equipped with an endless belt ( 74) which is driven to run adjacent to said lower fluted roll ( 18); in which said liner ( 66) is pressed against the glued crests of corrugation of said corrugating medium ( 20) fed along the circumference of said lower fluted roll ( 18) to be pasted with said corrugating medium ( 20) and form a single-faced corrugated board sheet; characterized in that said application mechanism ( 54) is provided with a drive roll ( 68) which is driven to be rotated by a suitable drive source, a preheating roll ( 70) into which a high-temperature steam is distributed, and a 29 - tension roll ( 72) which can apply tension to said endless belt ( 74); said endless belt ( 74) being extended over said three rolls ( 68,70,72).

11 The single facer according to Claim 10, wherein said preheating roll ( 70) is disposed upstream than said lower fluted roll ( 18), with respect to the direction of feeding said corrugating medium ( 20), while said drive roll ( 68) is disposed downstream than said lower fluted roll ( 18); the portion of said endless belt ( 74) locating between said two rolls ( 70,68) being pressed against said lower fluted roll ( 18) via said corrugating medium ( 20) fed along the circumference of said lower fluted roll ( 20) and said liner ( 66) fed along the circumference of said preheating roll ( 70) by said endless belt ( 74).

12 A single facer substantially as hereinbefore described with reference to the accompanying drawings.