Patent Publication Number: US-2022212311-A1

Title: Edge Sanding Device

Description:
COPYRIGHT NOTICE 
     A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever. 
     BACKGROUND 
     The invention relates to the field of electric woodworking machines. Electric woodworking machines may accept a workpiece into an entrance of the machine, pass the workpiece through the machine, and deliver the workpiece at an exit of the machine. The workpiece delivered at the exit of the machine may be planed, sanded, shaped, or otherwise modified from its original form. Machines that sand an edge of the workpiece use drum or belt sanders which may leave grooves on the surface of the workpiece. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Certain illustrative embodiments illustrating organization and method of operation, together with objects and advantages may be best understood by reference to the detailed description that follows taken in conjunction with the accompanying drawings in which: 
         FIG. 1  is an isometric detail view of an edge sanding device consistent with certain embodiments of the present invention illustrating the one or more edge sanding stations on the right and an individual finishing station on the left. 
         FIG. 2  is a rear isometric view of an edge sanding device consistent with certain embodiments of the present invention. 
         FIG. 3  is a front isometric view of an edge sanding device consistent with certain embodiments of the present invention. 
         FIG. 4  is a rear detail view of an edge sanding device consistent with certain embodiments of the present invention. 
         FIG. 5  is an isometric detail view of an edge sanding device consistent with certain embodiments of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     While this invention is susceptible of embodiment in many different forms, there is shown in the drawings and will herein be described in detail specific embodiments, with the understanding that the present disclosure of such embodiments is to be considered as an example of the principles and not intended to limit the invention to the specific embodiments shown and described. In the description below, like reference numerals are used to describe the same, similar or corresponding parts in the several views of the drawings. 
     The terms “a” or “an”, as used herein, are defined as one or more than one. The term “plurality”, as used herein, is defined as two or more than two. The term “another”, as used herein, is defined as at least a second or more. The terms “including” and/or “having”, as used herein, are defined as comprising (i.e., open language). The term “coupled”, as used herein, is defined as connected, although not necessarily directly, and not necessarily mechanically. 
     Reference throughout this document to “one embodiment”, “certain embodiments”, “an embodiment” or similar terms means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearances of such phrases or in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments without limitation. 
     The edge sanding device (hereinafter invention) may be a tool for sanding an edge of a workpiece. The workpiece may be moved through a cabinet from an infeed to an outfeed by a conveyance. The workpiece may pass one or more edge sanding stations as the workpiece moves through the cabinet. As the workpiece passes an individual edge sanding station selected from the one or more edge sanding stations, the individual edge sanding station may move an orbital sander from a quiescent position to a sanding position thus pressing a sanding disk of the orbital sander against the edge of the workpiece to sand the edge. 
     The orbital sander may offer distinct advantages compared to spinning drum sanders. As a non-limiting example, the orbital sander may avoid straight-line gouges and scuff marks that may be left by spinning drum sanders. 
     The one or more edge sanding stations may initially hold the orbital sanders in the quiescent position. Each of the individual edge sanding stations may independently move the orbital sander from the quiescent position to the sanding position upon sensing the proximity of the workpiece at the individual edge sanding station if the individual edge sanding station is enabled. The individual edge sanding station may move the orbital sander from the sanding position to the quiescent position when the proximity of the workpiece is no longer sensed. 
     The individual edge sanding station may comprise the orbital sander, a sander enclosure, a linear actuator, and a workpiece sensor. The individual edge sanding station may be coupled to the cabinet such that the orbital sander may move towards a front and a rear of the cabinet between the quiescent position and the sanding position. 
     In some embodiments, the individual edge sanding station may comprise a vacuum attachment. The vacuum attachment may be a shroud surround a sanding head. The vacuum attachment may suction sawdust away from the sanding head. The vacuum attachment may comprise a nozzle located adjacent to the sanding head and a vacuum hose coupling the nozzle to a vacuum device. 
     In some embodiments, the sanding disks at each of the one or more edge sanding stations may vary on coarseness such that the workpiece encounters the coarsest sandpaper closest to the infeed and encounters decreasing coarseness as the workpiece moves towards the outfeed. 
     In some embodiments, the invention may comprise one or more finishing stations. As non-limiting examples, each of the one or more finishing stations may comprise a finishing station sander having a brush, flap wheel, and/or sanding mop head to smooth corners of the workpiece. Each of the one or more finishing stations may comprise one of the workpiece sensors such that the one or more finishing stations operate only in the presence of the workpiece. 
     The orbital sander may be an off-the-shelf tool for sanding wood. The orbital sander may move the sanding disk in a rotary motion to abrade the wood. Use of off-the-shelf tolls may lower maintenance costs and decrease repair times. The orbital sander may comprise a sander body and the sanding head. The sander body may house a motor and a trigger. The trigger may energize the motor when the trigger is activated. As used in the invention, the trigger of the orbital sander may be constrained to the activated position such that operation of the orbital sander may be controlled by applying and removing power. As non-limiting examples, one or more straps or zip ties may retain the trigger in the activated position. A shaft of the motor may rotate when the orbital sander is energized. Rotation of the shaft may cause rotation of the sanding head. 
     The sanding head may be a circular holder for the sanding disk. The sanding disk may be a round sheet of sand paper. The sanding disk may removably couple to the sanding head. As non-limiting examples, the sanding disk may couple to the sanding head using an adhesive of hook-and-loop fasteners. The sanding disk may comprise an abrasive side that is exposed when the sanding disk is coupled to the sanding head. The abrasiveness of the abrasive side may be defined by the grit of the sanding disk. The grit may be a coarseness rating where smaller values denote more coarseness and larger value denote less coarseness. As non-limiting examples, the grit values may be defined by standards groups such as CAMI (Coated Abrasive Manufacturers Institute, now part of the Unified Abrasives Manufacturer&#39;s Association) in the U.S., the European FEPA (Federation of European Producers of Abrasives), and the Japanese Industrial Standards Committee (JIS). The FEPA system is the same as the ISO 6344 standard. 
     In some embodiments, the orbital sander may be a random orbital sander. A random orbital sander may incorporate an additional mechanism between the motor and the sanding head such that the sanding disk rotates around the center of the sanding head while the center of the sanding head moves in a circular motion relative to the sander body. The rotational axis of the sanding disk around the sanding head and the rotational axis of the sanding head relative to the sander body may be parallel such that the sanding disk may move in a single plane despite being influenced by two rotational components. Thus, the motion of the sanding disk is complex and may prevent the sanding disk from passing over a given point on the wood twice in the same direction. 
     The sanding disk may be held in a vertical orientation at each of the individual edge sanding stations. The plane of rotation of the sanding disk may coincide with the edge of the workpiece when the individual edge sanding station is moved to the sanding position such that the sanding disk may sand the edge of the workpiece. 
     The sander enclosure may retain the orbital sander. The sander enclosure may be moved by the linear actuator between the quiescent position and the sanding position. The sander enclosure may open to remove and insert the orbital sander. The sander enclosure may be reconfigurable to accept more than one model of sander. As non-limiting examples, a selection of spacers and/or moveable armatures may press against the outside of the orbital sander to conform to the size and shape of the orbital sander. 
     The linear actuator may move the sander enclosure between the quiescent position and the sanding position. In some embodiments, the linear actuator may comprise a guided air cylinder. The guided air cylinder may comprise an actuator body, a pneumatic cylinder, dual guide rods, and an actuator mount. The actuator body may be coupled to the sander enclosure. The actuator body may be moved by the pneumatic cylinder and may in turn move the sander enclosure. The pneumatic cylinder may be an air-activated motor. One end of a shaft of the pneumatic cylinder may be coupled to the actuator mount. The opposite end of the shaft may be coupled to a piston within the actuator body. Air pressure applied to a first side of the piston may move the actuator body in a first direction relative to the actuator mount. Movement in the first direction may move the actuator body from the quiescent position to the sanding position. Air pressure applied to a second side of the piston may move the actuator body in a second direction relative to the actuator mount. Movement in the second direction may move the actuator body from the sanding position to the quiescent position. 
     The dual guide rods may be parallel cylindrical shafts that are oriented parallel to the pneumatic cylinder. One end of the dual guide rods may be coupled to the actuator mount. The opposite ends of the dual guide rods may pass through guide apertures in the actuator body. The dual guide rods may orient and guide movement of the actuator body as the actuator body slides along the dual guide rods. The actuator mount may couple to the cabinet such that the guided air cylinder is positioned along the path of the workpiece. 
     In some embodiments, the individual edge sanding station may comprise one or more paper change shims to adjust for characteristics of the sanding disk. As a non-limiting example, when the sanding disk is changed from a coarser grit to a less coarse grit, the distance that the linear actuator moves towards the workpiece may need to be modified. The one or more paper change shims may limit the range of motion of the linear actuator and may thereby limit or expand the range of motion of the sanding disk towards the workpiece. 
     The workpiece sensor may detect the presence of the workpiece at the individual edge sanding station and may electrically signal the presence of the workpiece to control electronics. Responsive to input from the workpiece sensor indicating the presence of the workpiece, the control electronics may energize the orbital sander and may apply air pressure to the guided air cylinder to move the orbital sander from the quiescent position to the sanding position. When the workpiece has moved past the individual edge sanding station, the workpiece sensor may electrically signal the absence of the workpiece to the control electronics. Responsive to input from the workpiece sensor indicating the absence of the workpiece, the control electronics may deenergize the orbital sander and may apply air pressure to the guided air cylinder to move the orbital sander from the sanding position to the quiescent position. The workpiece sensor may be coupled to the cabinet via a sensor mounting bracket and may be located adjacent to the sanding head of the individual edge sanding station and adjacent to the workpiece such that the workpiece sensor may detect the presence of the workpiece adjacent to the individual edge sanding station. 
     In some embodiments, the workpiece sensor may be a proximity sensor. As non-limiting examples, the proximity sensor may sense proximity of the workpiece based upon changes in capacitance, inductance, density, optical properties, reflected electromagnetic fields, ultrasonic sound, or combinations thereof. 
     The cabinet may be adapted to protect an operator from injury and to prevent damage to the invention. The operator may stand at the front of the cabinet while operating the invention. The one or more edge sanding stations may be located at the rear of the cabinet. The cabinet may comprise a frame, a housing, a moveable safety shield, a stationary safety shield, and the conveyance. The frame may support the stationary safety shield, the conveyance and the one or more edge sanding stations. The housing may be cover panels that cover mechanical equipment, especially moving machinery such as motors, gears, pulleys, and belts. 
     The moveable safety shield may be a raisable barrier that may cover the one or more edge sanding stations. The moveable safety shield may be hingedly coupled to the stationary safety shield. The moveable safety shield may be raised to provide access to the one or more edge sanding stations for maintenance. The moveable safety shield may be lowered to operate the invention. In some embodiments, a safety interlock may prevent operation of the invention while the moveable safety shield is raised. In some embodiments, the stationary safety shield may comprise a dust collection port. The dust collection port may be coupled to a vacuum system to collect the sawdust produced by sanding. 
     The conveyance may move the workpiece through the invention from the infeed to the outfeed. Specifically, the operator may insert the workpiece from the front of the invention by pushing the workpiece rearwards until the workpiece is stopped by a rear fence and is aligned with the infeed. The operator may then move the workpiece laterally to move the workpiece into the infeed. The workpiece may be pulled laterally by the conveyance towards the outfeed and may be sanded by the one or more edge sanding stations as the workpiece moves. The workpiece may be released by the invention at the outfeed and the workpiece may be collected by the operator for the next operation. 
     The conveyance may comprise a bottom conveyor and a top limiter. The bottom conveyor may be located below the workpiece and may follow a looping route through the cabinet. The bottom conveyor may move from the infeed to the outfeed following an upper path of the bottom conveyor such that the bottom conveyor may carry the workpiece from the infeed to the outfeed. The bottom conveyor may then curve down and return to the infeed following a lower path of the bottom conveyor. Upon reaching the infeed, the bottom conveyor may return to the upper path and repeat the looping route. As a non-limiting example, the bottom conveyor may wrap around a wheel at each end of the conveyance. In some embodiments, the bottom conveyor may be guided and/or supported by armatures that are coupled to the frame. 
     The top limiter may press down on the workpiece as the workpiece travels through the invention such that the workpiece is maintained in a level orientation while being sanded. As a non-limiting example, the top limiter may comprise a plurality of rollers that are arranged above the workpiece. In some embodiments, the top limiter may be raised and lowered to compensate for the thickness of the workpiece by actuating a height adjuster. 
     One or more control panels may be adapted for the operator to control the operation of the invention. The one or more control panels may comprise a plurality of operator controls. In some embodiments, frequently used controls for enabling and disabling sanding stations may be located on control panels located on the front of the cabinet and less frequently used controls for adjusting air pressure may be located on control panels located on the rear of the cabinet. 
     The plurality of operator controls may comprise a plurality of edge sanding station enable controls, a plurality of edge sanding station pressure adjustments, a master on/off, and a plurality of finishing station enable controls. 
     Each of the plurality of edge sanding station enable controls may correspond to one of the individual edge sanding stations. Each of the plurality of edge sanding station enable controls may enable and disable the individual edge sanding station that the control is associated with. When enabled, the individual edge sanding station may sand the workpiece as the workpiece passes the individual edge sanding station. When disabled, the individual edge sanding station may remain quiescent as the workpiece passes the individual edge sanding station. 
     Each of the plurality of edge sanding station pressure adjustments may correspond to one of the individual edge sanding stations. Each of the plurality of edge sanding station pressure adjustments may increase and decrease the air pressure applied to the individual edge sanding station. Increased air pressure may cause the orbital sander that is associated with the control to apply more sanding pressure to the workpiece and decreased air pressure may cause the orbital sander to apply less sanding pressure to the workpiece. 
     The master on/off may control power to the invention as a whole. Placing the master on/off in the OFF position may deenergize the conveyance, the one or more edge sanding stations, and the one or more finishing stations. Placing the master on/off in the ON position may permit the conveyance, the one or more edge sanding stations, and the one or more finishing stations to operate according to the state of the plurality of operator controls and the workpiece sensors. 
     Each of the plurality of finishing station enable controls may correspond to one of the one or more finishing stations. Each of the plurality of finishing station enable controls may enable and disable an individual finishing station that the control is associated with. When enabled, the individual finishing station may sand the workpiece as the workpiece passes the individual finishing station. When disabled, the individual finishing station may remain quiescent as the workpiece passes the individual finishing station. 
     Turning now to  FIG. 1 , the figure illustrates a detail of the edge sanding device. The workpiece  900  is moved through the edge sanding device by the bottom conveyor  220  with the edge  902  of the workpiece  900  presented for sanding. The top limiter  230  may press the workpiece  900  down onto the bottom conveyor  220 . The workpiece sensor  330  mounted on the sensor mounting bracket  336  may detect the presence of the workpiece  900 . Responsive to this detection, the linear actuator  310 , mounted to the edge sanding device via the actuator mount  320 , may be activated by the pneumatic cylinder  316  to move the orbital sander towards the workpiece  900 , with the actuator body  314  guided by the dual guide rods  318 . The orbital sander may be housed within the sander enclosure  300  with the sanding head  280  accessible for sanding the workpiece  900 . The one or more paper change shims  348  may be interchangeable to adjust the orbital sander positioning for differences in characteristics of the sanding disks  290 . The finishing station sander  354  may smooth corners of the workpiece  900  as the workpiece  900  moves past the finishing station sander  354 . 
     Turning now to  FIG. 2 , the figure illustrates detail from the rear  248  side of the cabinet  200 . The workpiece may be inserted from the front  246  may be pushed towards the rear  248  until the workpiece is against the rear fence  212 . The operator may then move the workpiece laterally until the workpiece is carried by the bottom conveyor  220  through the edge sanding device. 
     Turning now to  FIG. 3 , the figure illustrates detail from the front  246  side of the cabinet  200 . The workpiece  900  may be inserted from the front  246  and may be moved by the bottom conveyor  220  while pressed down by the top limiter  230 . On the rear  248  of the edge sanding device, the stationary safety shield  208  and the moveable safety shield  204  cover the sanding equipment for safety and to contain the sawdust. The sawdust may be vacuumed from within the moveable safety shield  204  via vacuum equipment connected to the dust collection port  210 . The moveable safety shield  204  may be lifted to provide maintenance access. The control electronics  380  may be located anywhere within the edge sanding device and here the control electronics  380  are shown in the bottom portion of the cabinet. The control electronics  380  may be in electrical communication with the plurality of operator controls  362  located on the one or more control panels  360  and with sensor located adjacent to each sander and may determine when to energize the sanders and when to activate the linear actuators to move the sanders based upon the state of the plurality of operator controls  362  and the sensors. 
     Turning now to  FIG. 4 , the figure illustrates details of the sanding equipment within the invention  100 . Here, the infeed  240  is on the right of the figure and the outfeed  242  is on the left of the figure. The workpiece  900  may be carried by the bottom conveyor  220  from the infeed  240  of the cabinet  200  to the outfeed  242 . During the transit, the workpiece  900  may be held down against the bottom conveyor  220  by the top limiter  230 . The edge  902  of the workpiece  900  is presented for sanding by the sanding heads  280  of the one or more edge sanding stations  250 . The sander may be located within the sander enclosure  300  with the sanding head  280  accessible adjacent to the workpiece  900 . The sanding head  280  may be moved towards and away from the workpiece  900  by the pneumatic cylinder  316  of the linear actuator  310 . The workpiece  900  may also be sanded by the finishing station sander  354  of the one or more finishing stations  350  to smooth corners of the workpiece  900 . The sawdust produced by sanding may be vacuumed away via the dust collection port  210  located on the stationary safety shield  208 . The one or more paper change shims  348  may be interchangeable to adjust the position of the sanding head  280  to compensate for differences in characteristics of the sandpaper. 
     Turning now to  FIG. 5 , the figure illustrates details of the sanding equipment as seen from the direction of the outfeed. The workpiece  900  may be carried by the bottom conveyor  220  with the edge  902  of the workpiece  900  exposed for sanding. The workpiece  900  may be retained on the bottom conveyor  220  by the top limiter  230 . The workpiece sensor  330  coupled to the edge sanding device via the sensor mounting bracket  336  may detect the presence of the workpiece  900  at one or the orbital sanders and may signal the presence of the workpiece  900  to control electronics. In response, the control electronics may energize the orbital sander and may move the sander enclosure  300  in the first direction  322  to the sanding position  392  such that the sanding head  280  may press the sanding disk  290  against the edge  902  of the workpiece  900 . Movement of the sander enclosure  300  may result from activation of the pneumatic cylinder  316  in the linear actuator  310 . Once the workpiece  900  has passed, the workpiece sensor  330  may signal the control electronics that the workpiece  900  is no longer present next to the orbital sander. In response, the control electronics may move the sander enclosure  300  in the second direction  324  to the quiescent position  390  and may deenergize the orbital sander. The figure also shows the one or more paper change shims  348  in position on the linear actuator  310 . 
     In use, the invention  100  may be prepared by placing the sanding disks  290  of a desired grit on the sanding heads  280  at each of the orbital sanders. In some embodiments, the sanding disks  290  at each of the one or more edge sanding stations  250  may vary in coarseness such that the workpiece  900  encounters the coarsest sandpaper closest to the infeed  240  and encounters decreasing coarseness as the workpiece  900  moves towards the outfeed  242 . An operator may insert the workpiece  900  from a front  246  of the invention  100  by pushing the workpiece  900  rearwards until the workpiece  900  is stopped by a rear fence  212  and is aligned with the infeed  240 . The operator may then move the workpiece  900  laterally to move the workpiece  900  into the infeed  240 . The workpiece  900  may be pulled laterally by the conveyance towards the outfeed  242  and may be sanded by the one or more edge sanding stations  250  as the workpiece  900  moves. At each of the one or more edge sanding stations  250 , the workpiece sensor  330  may detect the presence of the workpiece  900  and may signal the control electronics  380 . Responsive to detecting the presence of the workpiece  900  at the orbital sander, the control electronics  380  may energize the orbital sander and may activate the linear actuator  310  to move the orbital sander from the quiescent position  390  to the sanding position  392 . In some embodiments, the workpiece  900  may encounter the one or more finishing stations  350  which may smooth corners of the workpiece  900 . The workpiece  900  may be released by the invention  100  at the outfeed  242  and the workpiece  900  may be collected by the operator for the next operation. 
     While certain illustrative embodiments have been described, it is evident that many alternatives, modifications, permutations and variations will become apparent to those skilled in the art in light of the foregoing description.