Method and apparatus for positioning and locking a glue roll for a single facer in operative position

Information

  • Patent Grant
  • 6601282
  • Patent Number
    6,601,282
  • Date Filed
    Tuesday, January 15, 2002
    22 years ago
  • Date Issued
    Tuesday, August 5, 2003
    21 years ago
Abstract
A glue machine for a corrugator single facer utilizes a system of simultaneously operated linear actuators to move the glue machine from an idle position adjacent the single facer to a locked position on the single facer, and then to a running position with the glue machine glue roll in a pre-established position with respect to a corrugating roll on the single facer. The glue machine is carried on laterally spaced pairs of front wheels and rear wheels mounted on pivot arms. The linear actuators are preferably air cylinders interconnecting front and rear wheel pivot arms to provide sequential glue machine frame movement from the idle to the locked position, followed by movement to the running position.
Description




FIELD OF THE INVENTION




The present invention pertains to a single facer machine for the manufacture of a single face corrugated web and, more particularly, to a method and apparatus for positioning and locking the glue roll of a separate glue machine with respect to a corrugating roll on the single facer.




BACKGROUND OF THE INVENTION




In the manufacture of corrugated paperboard, a single facer machine is used to corrugate the medium web, apply glue to the flute tips on one face of the corrugated medium web, and bring a liner web into contact with the glued flute tips of the medium web while applying sufficient heat and pressure to provide an initial bond in the glue lines between the corrugated medium and the liner. For many years, single facers have typically included a pair of fluted corrugating rolls and pressure roll which are aligned so that the axes of all three rolls are generally coplanar. The medium web is fed into a corrugating nip formed by the interengaging corrugating rolls and, while the corrugated medium web is still on one of the corrugating rolls, adhesive is applied to the flute tips by a glue roll. The liner web is immediately thereafter brought into contact with the adhesive-coated flute tips of the medium web and the composite single face web then passes through the nip formed by the corrugating roll and the pressure roll. More recently, a significantly improved single facer machine has been developed in which the corrugating rolls comprise a large diameter heated bonding roll and a substantially smaller diameter corrugating roll, with the ratio of diameters being 3:1 or greater. This more recently developed single facer eliminates the need for a pressure roll.




In both the older style single facer, where the corrugating rolls are of approximately the same diameter, and the more recently developed single facer, where the large diameter fluted bonding roll cooperates with the small diameter fluted corrugating roll, glue that typically comprises a starch adhesive is applied to the flute tips of the corrugated medium web while the web is held on a corrugating roll by the use of a glue application roll. Typically, glue from a reservoir is applied to a doctor roll which in turn transfers a layer of adhesive to the glue roll which is spaced a very small distance from the corrugated medium being carried on one of the corrugating rolls. It is important to carefully control the glue roll gap to assure that a uniform and proper amount of glue is transferred to the flute tips of the medium web.




In modern single facers, it is typical to mount the entire glue machine on a separate and independent frame and to mount the remainder of the single facer apparatus on a main single facer frame. The single facer main frame is set in a fixed position and the glue machine is mounted to move from an operative position with respect to the single facer machine to a spaced position a substantial distance from the single facer. To accommodate this movement, the glue machine is typically mounted on wheels in a manner to permit it to be moved far enough away from the single facer main frame to permit access to both the single facer and the glue machine for maintenance, cleaning and repair. In accordance with the subject invention, an apparatus is disclosed for positioning and locking the glue roll on the glue machine and moving the glue roll into operative running position with respect to a corrugating roll on the single facer machine.




SUMMARY OF THE INVENTION




In accordance with the present invention, the glue machine frame is provided with a pair of laterally spaced front wheels that are attached to and support the frame on a rotatable front pivot arm. A pair of laterally spaced rear wheels are attached to and support the glue machine frame on a rotatable rear pivot arm. An actuator device connects the front and rear pivot arms and is operable to initially rotate the front pivot arm to move the front wheels from an idle position supporting the front of the glue machine frame on a horizontal support surface to a locked position with the front wheels lifted from the horizontal surface and the front of the glue machine frame lowered vertically into a pivotal position on laterally spaced support blocks on the glue machine frame. The actuator device is operable thereafter to rotate the rear pivot arm and move the rear wheels over the horizontal surface and to rotate the glue machine frame about the axis of the support blocks from the locked position to a running position defined by a glue machine frame abutment surface in contact with a single facer machine abutment surface.




In accordance with a preferred embodiment, each of the laterally spaced front and rear wheels is attached to the machine frame on a respective rotatable front and rear pivot arm. The actuator device comprises a linear fluid actuator that interconnects a front pivot arm and a rear pivot arm on each lateral side of the glue machine frame. The actuators are operable in unison to move from an extended position that establishes the idle position of the machine to an intermediate position that establishes the locked position, and then to a fully retracted position that establishes the running position. Preferably, each front wheel and each rear wheel is supported, respectively, by a pair of front pivot arms and a pair of rear pivot arms with each pair of arms rotatably supported on a wheel mounting shaft on opposite sides of its respective wheel, and the linear fluid actuators are pairs of air cylinders connecting each front and rear wheel pair. The apparatus also includes a front wheel stop on the glue machine that limits rotation of the front wheel on the front pivot arm in the direction of the locked position and sets said locked position. The apparatus also includes a rear pivot arm stop that is attached to the glue machine frame and limits rotation of the rear pivot arm in the direction of the extended position of the actuator establishing the idle position of the glue machine frame.




In the preferred embodiment, the support blocks comprise a pair of V-blocks, and the glue machine is provided with a pair of laterally spaced rollers that are aligned with the V-blocks in spaced relation thereto in the idle position and which move into bearing contact with the V-blocks in the locked position. In the preferred embodiment, the single facer machine abutment surface comprises a pair of stop blocks attached to the single facer frame, and the glue machine abutment surface comprises a pair of cam followers attached to the glue machine frame. The attachment of each cam follower to the glue machine frame is adjustable to vary the operative position of the glue roll in the running position. The glue machine is movable on the front and rear wheels over the horizontal support surface from the idle position to a service position in which the machine is spaced from the single facer machine.




Further in accordance with the present invention, a method for positioning and locking the glue roll of a glue machine and for moving the glue roll into operative position with respect to the corrugating roll of a single facer machine includes the steps of (1) supporting the glue machine on pairs of laterally spaced front wheels and rear wheels that are attached to the glue machine frame by respective pairs of rotatable front and rear pivot arms, (2) connecting the front and rear pivot arms with a linear actuator, (3) operating the actuator to initially rotate the front pivot arms and to move the front wheels from an idle position supporting the front of the glue machine frame on a horizontal surface to a locked position with the front wheels lifted from the horizontal surface and the front of the glue machine frame lowered vertically onto laterally spaced support blocks on the single facer machine frame, and (4) continuing operating the actuator to rotate the rear pivot arms and to move the rear wheels over the horizontal surface thereby rotating the glue machine on the support blocks from the locked position to a running position with a glue machine frame abutment surface in contact with a single facer machine abutment surface.




In accordance with the preferred method, the linear actuator comprises a fluid cylinder connecting a front pivot arm and a rear pivot arm on each lateral side of the glue machine frame, and the operating steps comprise (1) retracting the cylinders in unison from an extended position establishing the idle position to an intermediate position establishing the locked position, and (2) continuing retracting the cylinders to a retracted position establishing the running position. Most preferably, the fluid cylinders comprise air cylinders, and the method further includes steps of (1) positioning a front pivot arm stop on the glue machine frame in the path of front pivot arm rotation in the retracting direction to prevent rotation thereof past the locked position, and (2) positioning a rear pivot arm stop on the glue machine frame in the path of rear pivot arm rotation in the extending direction to prevent rotation thereof past the idle position.




In the preferred embodiment, the single facer abutment surface comprises a stop block attached to the single facer machine frame and the glue machine abutment surface comprises a cam follower attached to the glue machine frame, and the method comprises the additional step of adjusting the position of the cam follower to vary the operative position of the glue roll in the running position.











BRIEF DESCRIPTION OF THE DRAWINGS





FIGS. 1-3

are similar side elevation views of a single facer machine and an associated glue machine incorporating the glue roll locking and positioning apparatus of the present invention.





FIG. 4

is an enlarged top plan view detail taken on line


4





4


of FIG.


1


.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT




In

FIG. 1

, a single facer machine


10


includes a large diameter upper corrugating roll


11


, hereinafter also referred to as a bonding roll


11


, and a much smaller diameter lower corrugating roll


12


. Both rolls


11


and


12


are fluted and mounted for interengaging rotational movement on parallel axes, all in a manner well known in the art. A medium web


13


, which is typically pretreated by moistening and heating, is fed into a corrugating nip


14


formed by the interengaging corrugating rolls


11


and


12


. The small diameter corrugating roll


12


is held in nipping engagement with the bonding roll


11


by a variable force backing arrangement


15


. The backing arrangement includes a series of axially adjacent pairs of backing rolls


16


, each of which pairs has a pressure or back-up belt


17


entrained therearound. Each of the back-up belts


17


is positioned to bear directly against the fluted outer surface of the small diameter corrugating roll


12


. Each pair of backing rolls


16


and its respective back-up belt


17


is mounted on a linear actuator


18


. By individually controlled operation of each linear actuator


18


, the back-up belts


17


may be made to engage the small diameter corrugating roll with a selectively adjustable force. The bonding roll


11


, small diameter lower corrugating roll


12


and the backing arrangement


15


are all mounted on and carried by a single facer machine main frame


20


.




As the corrugated medium web


13


leaves the corrugating nip


14


, it remains on the surface of the large diameter bonding roll


11


. Immediately downstream from the nip


14


, a glue roll


21


, carried on the main frame


22


of a glue machine


23


, applies a liquid adhesive, typically starch, to the exposed flute tips of the corrugated medium web


13


. Immediately thereafter, a liner web


24


is brought into contact with the glued flute tips of the corrugated medium web by a liner delivery roll


25


(sometimes referred to as a generator roll), also carried on the single facer main frame


20


. The resulting freshly glued single face web


26


continues around a portion of the outer circumference of the large diameter bonding roll


11


which is internally heated, for example with steam, to cause the starch adhesive to be initially gelatinize and then enter the so-called “green bond” stage.




It is critically important for the strength and integrity of the single face web


26


that the glue, which is applied to the flute tips of the corrugated medium web


13


along the full length of the flutes, be applied in carefully metered amounts. The starch-based adhesive glue is supplied from a glue reservoir


27


mounted on the glue machine frame


22


and from which glue is initially taken up by a doctor roll


28


running in the reservoir. The doctor roll


28


, in turn, applies a carefully controlled layer of glue to the surface of the counterrotating glue roll


21


. The glue roll is set in an operative position with respect to the corrugated medium web


13


on the bonding roll


11


so that the glue is applied in carefully controlled amounts to the flute tips in glue lines that extend the full length of the flutes.




The glue machine


23


is designed to be moved into a cooperative position adjacent the single facer


10


, the glue machine frame


22


locked to the single facer frame


20


, and then moved slightly to a final operative running position with the glue roll


21


set at a predetermined distance from the bonding roll


11


carrying the medium web


13


. It is also known in the art to monitor the glue roll gap during operation and to adjust the position of the glue roll, if necessary, to maintain the proper gap where, for example, thermal expansion or the like results in a change in the gap during operation. It is also desirable to completely disconnect the glue machine from the single facer machine so the two can be completely separated to permit cleaning, maintenance, and repair. To accommodate all of the foregoing, the single facer frame


20


is typically bolted or otherwise fixed to the floor or other horizontal support surface


30


, whereas the glue machine


23


is mounted on wheels to accommodate positioning, adjustment and movement to and away from the single facer.




Referring also to

FIGS. 2-4

, the glue machine frame


22


is supported for rolling movement over the support surface


30


by a pair of laterally spaced front wheels


31


and a pair of similarly laterally spaced rear wheels


32


. Each front wheel


31


is mounted on and fixed to a wheel mounting shaft


33


for rotation therewith. The opposite axial ends of each wheel mounting shaft


33


are rotatably mounted on a pair of front pivot arms


34


via wheel bearings


35


, as best seen in FIG.


4


. The opposite upper ends of each of the front pivot arms


34


are pivotally attached to the glue machine frame


22


on a common front pivot


36


. Each of the rear wheels


32


is similarly mounted between the lower ends of a pair of rear pivot arms


37


. The opposite upper ends of the rear pivot arms


37


are pivotally attached to the glue machine frame


22


on a common rear pivot


38


.




Each aligned pair of a front pivot arm


34


and rear pivot arm


37


is interconnected with a linear actuator


40


, preferably comprising an air cylinder


41


. The front end of each cylinder includes a mounting shaft


42


that is pivotally attached via a pivot


45


to the lower end of the front pivot arm


34


near the front wheel


31


. The retractable and extendable cylinder rod


43


on the opposite end of the air cylinder


41


is connected by a rod end pivot


44


to the lower end of the rear pivot arm


37


adjacent the rear wheel


32


. Thus, referring particularly to

FIG. 4

, each of the pair of laterally spaced front wheels


31


is rotatably carried on the lower end of a pair of ago front pivot arms


34


which are, in turn, mounted to the glue machine frame


22


on a common front pivot


36


. Each of the pair of laterally spaced rear wheels


32


is similarly mounted as indicated above. The front and rear wheels are thus interconnected by four identical air cylinders


41


which serve to move the wheels from an idle position (

FIG. 1

) supporting the glue machine


23


for rolling movement over the horizontal support surface


30


, to an intermediate locked position (

FIG. 2

) attached to the single facer main frame


20


, and to a running position (

FIG. 3

) with the glue roll


21


operatively positioned with respect to the bonding roll


11


of the single facer (all as will be described in greater detail hereinafter).




Preferably, the front pivot arms


34


on both sides of the glue machine are interconnected with a torque tube


57


. Similarly, the rear pivot arms


37


on opposite sides of the machine are connected by a rear torque tube


58


. The torque tubes


57


and


58


maintain a necessary rigidity between the actuator systems on opposite sides of the machine, not allowing any loss of synchronization between the actuating cylinders


41


that could impart excessive movement to one side of the glue machine and not the other. Within the range of some small amount of movement in the couplings by which the torque tubes


57


and


58


are connected to the respective pivot arms


34


and


37


, the torque tubes cause the pivot arms on both sides of the machine to operate in unison.




Referring again to

FIG. 1

, the glue machine


23


has been moved to the idle position where it is supported immediately adjacent the single facer


10


on the front and rear wheels


31


and


32


. The idle position is established by contact between a pair of snubbers


49


mounted on opposite sides of the glue machine frame engaging vertical rear edges


39


of the single facer frame. In this position, a pair of laterally spaced cam followers


46


, rotatably attached to the glue machine frame


22


, are positioned directly above but spaced from a pair of V-block supports


47


secured to the single facer frame


20


. In the idle position, the rods


43


of the air cylinders


41


are fully extended and the lower ends of the rear pivot arms


37


are in their rearmost position with the upper ends thereof in contact with a pair of rear pivot arm stops


48


. The front wheels


31


are positioned slightly forward of and vertically below the front pivots


36


. This establishes an over dead center position in which the glue machine will remain locked if cylinder air pressure is accidentally lost. From the idle position of

FIG. 1

, the glue machine


23


may be rolled over the floor


30


away from the single facer frame to completely separate the glue machine from the single facer to provide space for cleaning, maintenance, or repair. Preferably, however, and referring again to

FIG. 4

, each front wheel


31


is driven by an air motor


50


mounted directly on the axial inner end of the wheel mounting shaft


33


. Each air motor


50


includes a reducer


51


, the output shaft of which is keyed directly to the wheel mounting shaft


33


. The glue machine may thus be driven to or from the

FIG. 1

position.





FIG. 2

shows movement of the glue machine


23


from the idle position to a locked position on the single facer main frame


20


. As the cylinder rods


43


of the air cylinders


41


are caused to retract in unison, the front pivot arms


34


will rotate in a rearward direction (counterclockwise) about their respective front pivots


36


. As the front wheels


31


pivot rearwardly in circular arcs on the front pivot arms


34


, the entire front end of the glue machine


23


will drop slightly until the cam followers


46


drop into the V-block supports


47


. As the cylinders


41


continue to retract, the glue machine will rotate about the common axis of the spaced cam followers


46


and the front wheels


31


will lift off the floor


30


until the front wheels engage respective front stop edges


29


on opposite sides of the glue machine frame


22


. As the front pivot arms


34


approach respective position sensors


52


on the glue machine frame


22


signals are generated to indicate that the front wheels


31


are fully retracted. At this point shown in

FIG. 2

, the front of the glue machine is fully supported and locked as a result of the mass of the glue machine in the V-block supports on the single facer frame and the front wheels


31


are completely off the ground. The foregoing movement occurs first, in preference to rotation of the rear pivot arms


37


, because the force required to lift the rear of the glue machine, as will be discussed, is several times the force required to rotate the front pivot arms


34


and drop the front of the machine into the support blocks


47


.




In

FIG. 3

, it can be seen that continued retraction of the air cylinder rods


43


will next cause the rear pivot arms


37


to move forwardly in clockwise rotation about the rear pivots


38


. In the locked position of

FIG. 2

, the rear pivot arms


37


extend downwardly and rearwardly from the rear pivots


38


such that continued retraction of the air cylinder rods


43


causes the upper ends of the rear pivot arms


37


to move away from the rear pivot arm stops


48


and the rear wheels


32


to move under the rear pivots


38


, thereby causing the rear of the glue machine


23


to be raised. This upward movement of the rear of the glue machine comprises pivotal rotation of the rear of the machine about the common axis of the cam followers


46


locked in the V-block supports


47


. Upward rotation of the rear of the glue machine is halted by engagement between a pair of laterally spaced cam followers


53


on the upper edge of the glue machine frame


22


and a pair of stop blocks


54


on the single facer frame


20


. Contact between the cam followers


53


and the respective stop blocks


54


establishes the running position of the glue machine by fixing the gap between the glue roll


21


and the bonding roll


11


. If for any reason, the arrangement of the stop blocks


54


and cooperating cam followers is inoperative, a safety stop is provided by contact between the rear wheels


32


and the rear edge of the glue machine frame


22


.




Each of the cam followers


53


is mounted for independent adjustment on an adjustment mechanism


55


. Preferably, each adjustment mechanism


55


operates independently and in response to signals generated by a gap sensor


56


mounted on each side of the glue machine frame


22


in a position to continuously monitor the actual glue roll gap and to adjust the same as a result of changing dimensions caused, for example, by thermal expansion during machine operation.




When it is desired to unlock the glue machine from the single facer, the process described above is simply reversed. Extension of the cylinder rods


43


of the air cylinders


41


initially causes rearward rotation of the rear pivot arms


37


that in turn causes rotation of the glue machine about the axis of the cam wheels


46


in the V-block supports


47


, whereupon the cam followers


53


drop out of contact with the stop blocks


54


until the upper ends of the rear pivot arms


37


again engage the rear pivot arm stops


48


(FIG.


2


). Thereafter, continued extension of the cylinders


41


causes the front pivot arms


34


to move forwardly (clockwise rotation about the front pivots


36


), causing the front wheels


31


to engage horizontal support surface


30


and lift the front of the glue machine vertically, causing the cam wheels


46


to disengage from the V-block supports


47


(FIG.


1


). From this idle position of the glue machine, operation of the air motors


50


will drive the glue machine out from under the single facer main frame


20


to open the space therebetween for maintenance, repair or the like. The movement of the glue machine from an idle position to a locked position, and then to a running position, utilizing a single set of linear actuators provides economies of operation as well as machine construction.



Claims
  • 1. An apparatus for positioning and locking a glue roll supported on the frame of the glue machine and moving the glue roll into operative position with respect to a corrugating roll supported on the frame of a single facer machine, said apparatus comprising:a pair of laterally spaced front wheels attached to and supporting the glue machine frame on a rotatable front pivot arm; a pair of laterally spaced rear wheels attached to and supporting the glue machine frame on a rotatable rear pivot arm; and, an actuator device connecting said front and rear pivot arms and operable to initially rotate the front pivot arm to move the front wheels from an idle position supporting the front of the glue machine frame on a horizontal support surface to a locked position with the front wheels lifted from the horizontal surface and the front of the glue machine frame lowered vertically into a pivotal position on laterally spaced supports defining a common axis on the single facer machine frame and the glue machine frame and, said actuator device operable thereafter to rotate the rear pivot arm and move the rear wheels over the horizontal surface to rotate the glue machine frame about the axis of the supports from the locked position to a running position defined by a glue machine frame abutment surface in contact with a single facer machine abutment surface.
  • 2. The apparatus for positioning and locking a glue roll in claim 1 wherein said actuator device comprises:a linear fluid actuator interconnecting a front pivot arm and a rear pivot arm on each lateral side of the glue machine frame; said actuator operable in unison to move from an extended position establishing the idle position to an intermediate position establishing the locked position, and then to a retracted position establishing the running position.
  • 3. The apparatus for positioning and locking a glue roll in claim 2 wherein each front wheel and each rear wheel is supported by a respective pair of front pivot arms and rear pivot arms, each pair of arms rotatably supported on a wheel mounting shaft on opposite sides of a wheel, and said linear fluid actuators comprise two air cylinders connecting each front and rear wheel pair.
  • 4. The apparatus for positioning and locking a glue roll in claim 2 including a front wheel stop on the glue machine frame to limit rotation of the front wheels on said front pivot arm in the direction of the locked position.
  • 5. The apparatus for positioning and locking a glue roll in claim 2 including a rear pivot arm stop attached to the glue machine frame to limit rotation of said rear pivot arm in the direction of the extended position and to set the idle position of the glue machine frame.
  • 6. The apparatus for positioning and locking a glue roll in claim 1 wherein the supports comprise a pair of V-blocks on the single facer machine frame, and further including a pair of laterally spaced rollers mounted on the glue machine frame on said pivotal axis, said rollers aligned with the V-blocks in spaced relation thereto in the idle position and in bearing contact therewith in the locked position.
  • 7. The apparatus for positioning and locking a glue roll in claim 1 wherein said single facer machine abutment surface comprises a stop block attached to the single facer machine frame, and said glue machine abutment surface comprises a cam follower attached to the glue machine frame.
  • 8. The apparatus for positioning and locking a glue roll in claim 7 wherein the attachment of the cam follower to the glue machine frame is adjustable to vary the running position of the glue roll in the running position.
  • 9. The apparatus for positioning and locking a glue roll in claim 1 wherein the glue machine is movable on the front and rear wheels over the horizontal support surface from the idle position to a service position spaced from the single facer machine.
  • 10. A method for positioning and locking a glue roll supported on the frame of a glue machine and for moving the glue roll into operative position with respect to a corrugating roll supported on the frame of a single facer machine, said method comprising the steps of:(1) supporting the glue machine on pairs of laterally spaced front wheels and rear wheels attached to the glue machine frame by respective pairs of rotatable front and rear pivot arms; (2) connecting the front and rear pivot arms with a linear actuator; (3) operating the actuator to initially rotate the front pivot arms and move the front wheels from an idle position supporting the front of the glue machine frame on a horizontal surface to a locked position with the front wheels lifted from the horizontal surface and the front of the glue machine frame lowered vertically onto laterally spaced support blocks on the single facer machine frame; and, (4) continuing operating the actuator to rotate the rear pivot arms and move the rear wheels over the horizontal surface to rotate the glue machine on the support blocks from the locked position to a running position with a glue machine frame abutment surface in contact with a single facer machine abutment surface.
  • 11. The method as set forth in claim 10 wherein said linear actuator comprises a fluid cylinder connecting a front pivot arm and a rear pivot arm on each lateral side of the glue machine frame, and said operating steps comprise:(1) retracting the cylinders in unison from an extended position establishing the idle position to an intermediate position establishing the locked position; and, (2) continuing retracting the cylinder to a retracted position establishing the running position.
  • 12. The method as set forth in claim 11 wherein said fluid cylinders comprise air cylinders, and including the steps of:(1) positioning a front stop edge on the glue machine frame in the path of the front wheels moving with front pivot arm rotation in the retracting direction to prevent rotation of the wheels past the locked position; and, (2) positioning a rear pivot arm stop on the glue machine frame in the path of rear pivot arm rotation in the extending direction to prevent rotation thereof past the idle position.
  • 13. The method as set forth in claim 10 wherein said single facer abutment surface comprises a stop block attached to the single facer machine frame and said glue machine abutment surface comprises a cam follower attached to the glue machine frame, and comprising the additional step of adjusting the position of the cam follower to vary the operative position of the glue roll in the running position.
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