Abstract:
A support device with air caster units is provided sufficient to lift and support heavy rollers or rolls inside an endless belt so that the rolls can be removed from within the endless belt and the endless belt replaced.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to the method and apparatus for handling endless paper-making belts, and more particularly, to a device for installing or removing an endless paper-making belt from around heavy rolls. 
     2. Description of the Prior Art 
     The handling of large endless belts, especially in the light of their breadth, provides difficulties when installing such endless belts around heavy rolls such as those found in the forming section of a paper-making machine or the stretcher rolls used in the manufacture of paper-making belts. On paper machines these belts are called wires, fabric or felts. On conventional paper-making machines, when changing the forming fabric, the old fabric on the machine is suspended while the breast and couch rolls are held in a cantilever manner while the various other suction rolls and foils and suction boxes are also held in a cantilever manner. Tension is released on the fabric, and the fabric is removed from the free end of the rolls. 
     In the case of the stretching rolls used in the manufacture of these fabrics, the rolls are moved towards each other on bearing supports mounted on wheels travelling in tracks provided in the floor thereof. As the tension in the fabric is released, the fabric is held tent-like and the rolls are moved inwardly to the point where they are cantilevered so that the fabric can be removed over the end of the rolls and the new fabric replaced. The weight of the stretching rolls used in the manufacture of the fabric or the weight of the breast and couch rolls on a paper machine are such that a considerable support structure must be provided on the cantilevered side so as to support the full length of these rolls while the fabric is being removed and replaced. This problem is especially acute in the manufacture of paper-making belts since these belts are continuously being installed or removed from the stretcher rolls during their production. Accordingly, in the building in which the belts are being stretched, the floor must often be especially reinforced on the support side of the rolls in order to properly cantilever the stretching rolls which might sometimes exceed 40 feet. 
     SUMMARY OF THE INVENTION 
     It is an aim of the present invention to provide an apparatus and a method for overcoming certain problems in the handling of large endless belts, especially when they are installed on or removed from around heavy stretching rolls in the manufacture thereof or from paper-making machines. These rolls may be in excess of 40 ft. in width and 4 ft. in diameter. 
     An apparatus in accordance with the present invention includes a roll support platform including air supported casters mounted to the bottom of said platform adapted for lifting and gliding the platform and the supported roll over the belt such that the rolls can be completely removed from within the endless belt to allow the belt to be changed. 
     A method in accordance with the present invention includes the steps of changing an endless paper-making belt, including first releasing the tension on the belt, supporting the end rolls on air casters such that the rolls and support means are spaced from the floor and moving the supported rolls from within the belt clear of the belt so as to effect its change. 
     In a more specific embodiment of the present apparatus in accordance with the invention, the support platform includes an endless web adapted to pass under the air supported casters such that the endless web is in contact with the fabric as the support platform moves over the fabric, the endless web passing over the platform as the platform supporting the roll is moved. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Having thus generally described the nature of the invention, reference will now be made to the accompanying drawings, showing by way of illustration, preferred embodiments thereof, and in which: 
     FIG. 1 is a schematic view showing the fabric in side elevation with the rolls on an air-caster-support platform; 
     FIG. 2 is a schematic elevational view similar to FIG. 1 showing the rolls supported on the bearing supports rolling in the tracks; 
     FIG. 3 is a schematic side elevation similar to FIGS. 1 and 2 showing the rolls being moved outwardly within the fabric on the bearing supports; 
     FIG. 4 is an end elevation of the rollers shown as they would appear in FIG. 3; 
     FIG. 5 is an end elevation similar to FIG. 4 showing the stretching rolls mounted on the air-caster-support platforms and being moved clear of the fabric; 
     FIG. 6 is a top plan view of a different embodiment of a method of moving the rolls from within the fabric using the air-caster-support platform; 
     FIG. 7 is a fragmentary view, partly in cross-section, showing a still further manner of removing the wire from the rolls using an air-caster-support platform; 
     FIG. 8 is an enlarged fragmentary detailed view of a still further embodiment of the air support casters with a roll support platform; and 
     FIG. 9 is a fragmentary vertical cross-section taken along lines 9--9 of FIG. 8. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to FIGS. 1 through 5, there is shown a pair of stretcher rollers 12 and 14 and a belt 10. The belt 10 is endless and is in the process of being finished for use. The rolls 12 and 14 are normally mounted on bearing supports 16 and 18 which in turn have wheels 20 and 22 for movement in tracks embedded in the floor. In a normal stretching process, the rolls 12 and 14 are moved away from each other, stretching the fabric about the rolls 12 and 14. After this has been accomplished, the bearing supports 16 and 18 are moved inwardly towards each other, as shown in FIG. 2, and are allowed to position the rolls 12 and 14 over pillows 28 and 30 of a transporter including a platform 24. 
     The belt 10 can be hung by means of hangers 34 and 36 suspended from the ceiling 32 and supporting poles 38 and 40 which in turn hang the belt 10 as a tent so as to allow clear movement of the rolls 12 and 14. 
     The platform 24 is provided underneath and at each end thereof with so-called air casters 26. The air caster 26 includes a square steel plate or frame and a circular rubber curtain or annular diaphragm extending from the plate and air under pressure is fed into the space defined by the rubber skirt. Air eventually escapes between the skirt and the ground, but the air pressure contained within the annular skirt allows any air caster to be lifted and held off the ground even when supporting a great load. A typical air caster is supplied by Aero-Go Inc. under the trade mark &#34;AERO CASTER&#34;. It is contemplated that a cluster of air casters 26 would be supplied at each end of the platform 24, and the air casters as well as the platform 24 would be effective to lift the rolls 12 and 14 off of the bearing supports 16 and 18, and very little force would be required to move the otherwise heavy rolls 12 and 14 on the transporter clear of the belt 10, as shown in FIGS. 4 and 5. 
     Because the transporter 24 is supported on air over the floor and no portion of the transporter 24 is in contact with the belt 10, the rolls can thus be moved over the belt 10 without apparent damage to the belt 10. Accordingly, rather than having to provide excessively strong floor supports for cantilevering the rolls 12 and 14, they are merely positioned on the transporter 24 and moved out from within the belt 10, and the belt 10 can then be replaced by a new belt to be stretched. It is contemplated that similar versions could be used for changing the paper-making belts found on paper-making machines. 
     The remaining Figures show the different embodiments using the principle of an air caster for moving the rolls clear of the belt 10. For instance, in FIG. 6, where space might be limited, the rolls 42 and 44 are supported at one end and bearings mounted on a pivoting support 46 are adapted to pivot about a vertical axis. When the rolls 42 and 44 are brought together, the other ends of the shafts of the rolls 42 and 44 are supported on a transporter platform 48 also provided with air casters. The rolls 42 and 44 would then be moved by pivoting about the vertical axis into a position shown in dotted lines. The belt could then be easily cleared of the rolls 42 and 44. 
     The embodiment in FIG. 7 illustrates how the belt 10 can be moved clear of the rolls 59 rather than moving the rolls clear of the belt 10. In this case, the bearing support 64 is pivoted about a horizontal axis while the other end of the shaft 70 is supported on an air caster transporter. As air pressure is provided within the air casters 68, the transporter lifts off the surface of the ground, and in this case, off a moving metallic slat conveyor 66. Carriages 52 and 56, which move on guide rail 50, support the poles 60 by means of hangers 47 and 58, and the fabric is moved clear of the rolls by passing through the air space underneath the platform 68. In order not to damage the fabric, the conveyor 66 is provided so as to reduce the friction of the fabric as it passes underneath the air transporter platform 68. 
     In the embodiment shown in FIGS. 8 and 9, there is shown a pair of air caster transporters 76 and 90 with one transporter at each end of the rolls 72 and 74. Rolls 72 and 74 are supported at one end on respective pillows 86 and 87, each supported by transporter 76. The transporter 76 includes a platform and beams 80a and 80b, beams 82a and 82b, as well as cross-beams 83a and 83b. Underneath the transporter 76 is a cluster of air casters. An endless web 85 passes about the air casters 78, as shown in FIGS. 8 and 9, such that the pressure of the air in the casters acts on the inner side of the bottom run of the endless web 85 which is trained about the platform. The endless web should have a soft outer surface and a vinyl-like interior surface. The soft outer surface would reduce the possibility of damage to the fabric. As the transporter 76 carrying one end of the roll moves the endless web which is in contact with the fabric or the ground, it is forced to move such that the air casters are always over a static portion of the web 85 relative to the belt. The fragmented end of FIG. 8 shows the other transporter 90 including beams 89 and an endless web 96 with air casters 94 supported on the transporter 90. Of course, the features of the transporter are identical. 
     Referring to FIG. 9, the transporter 76 is, of course, double such that end beam 88 can connect segments of the transporter 76 and the respective endless web are shown at 84 and 85 while the casters are identified in both groups by the numeral 78.