Some of the objects of the invention having been stated, other objects will become evident as the description proceeds hereinafter, when taken in connection with the drawings described below。

BRIEF DESCRIPTION OF THE DRAWINGS

FIG。 1 is a front perspective view of the sanding apparatus of the present invention with parts broken away including parts from the support frame for the sanding head and the bearings for the upper and lower rollers;

FIG。 2 is a second front perspective view of the sanding apparatus of the present invention with parts broken away including parts from the upper and lower rollers and the support frame therebetween for better clarity of understanding;

FIG。 3 is a front perspective view of a second embodiment of the sanding apparatus of the present invention with parts broken away for better clarity of understanding; and

FIG。 3A is a front perspective view of the arcuate plate sanding belt tensioning mechanism shown in FIG。 3 with parts broken away for better clarity of understanding。

BEST MODE FOR CARRYING OUT THE

INVENTION

With particular attention now directed to FIGS。 1 and 2 of the drawings, the novel rotating belt sanding machine is generally designated 10。 Sanding machine 10 includes the sanding head generally designated 20 and the conveyor generally designated 60。 Sanding head 20 includes tension roller 22 and contact roller 24。 Upper tension roller 22 is supported by bearings 25A and 25B at each end thereof carried by supports 30A and 30B, and lower contact roller 24 is supported by bearings 26A and 26B at each end thereof carried by corresponding supports 28A and 28B at each end of contact roller 24。 An endless sanding belt 32 is entrained around upper tension roller 22 and lower contact roller 24。 Sanding head 20 is fixedly attached to vertically moveable frame element 34 (only one side of four-sided frame element 34 surrounding sanding head 20 is shown in FIG。 1) by sanding head support element 36 which extends normally outwardly from two opposing sides of frame element 34 and between tension roller 22 and contact roller 24。 A pair of spaced-apart and parallel eccentric shafts 38A and 38B are provided to impart translational orbital movement to sanding head 20 in a manner to be described hereinafter。 Eccentric shaft 38A extends from contact roller support 28A at its lower end, to tension roller support 30A at its upper end, and eccentric shaft 38B extends from contact roller support 28B at its lower end to tension roller support 30B (not shown) at its upper end。 As can be seen with reference to the drawings, eccentric shafts 38A and 38B when rotated will act to provide translational orbital movement to sanding head 20。

With reference to FIG。 2, it can be seen that two actuators 40A and 40B are provided in the top of sanding head support element 36 so as to urge tension roller 22 upwardly or downwardly as required in order to properly tension endless sanding belt 32 entrained around tension roller 22 and contact roller 24。 Two pneumatic actuators 42A, 42B are mounted on support 30B of tension roller 22 to automatically center sanding belt 32 by turning the shaft pin 22A。 Electric motor 44 drives contact roller 24 by means of belt 46 and pulley 48 mounted to the end shaft of contact roller

24。Second electric motor 50 serves to drive eccentric shafts 38A and 38B by means of pulley 50A mounted to electric motor 50 which drives idle pulley 52B at the end of eccentric shaft 38B by means of toothed belt 54。 Idle pulley 52B in turn serves to drive idle pulley 52A at the bottom end of eccentric shaft 38A by means of second toothed belt 56 which extends between idle pulley 52B and idle pulley 52A。

Conveyor 60 comprises endless feed belt 62 for carrying work piece WP beneath sanding head 20 to be acted upon by the combined rotation and orbital movements of sanding belt 32。 Feed belt 62 is entrained around driven roller 64 and idle roller 66。 Third electric motor 68 is provided to drive driven roller 64 through drive unit 70 which is a conventional gear transmission mechanism。