Abstract:
The invention is in a vacuum driven sander that is appropriate for drywall sanding, that utilizes a vacuum flow pulled therethrough to drive a turbine that includes an adjustable lock mounting through a bearing assembly to an eccentric to turn the eccentric that is connected to oscillate a sanding pad that mounts a section of sanding material, and that vacuum air flow also provides for removing sanded particles off from the sanded surface that are transported through the sander and a connected pipe or hose into a catchment container. The sander housing includes a pole mounting cylinder that projects outwardly from a housing top surface and is ported with equal spaced radial cavities formed around the port, and with a selected pair of cavities to receive each of a pair of stub axles of a pivot collar, providing a first pivot coupling that, along with a second pivot mounting of the collar to the end of a hollow bent tube, provides a universal coupling of the hollow bent tube to the sander body that allows for the pivoting of the sander whereby the sanding surface remains in engagement with the wall as it is moved up and down and across the wall. The hollow bent tube also includes a static discharge electrical connector that receives a female connector fixed to an end of a conductive wire for positioning in a sander pole that is mounted to the bent tube end, with the wire extending the length of the pole wherethrough the vacuum exhaust flow passes and conducts a static electric charge into the vacuum flow.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of The Invention  
           [0002]    This invention pertains to sanding devices, and in particular to a vacuum driven light weight sander that can be hand held or mounted onto a pole for use in sanding dry wall and is attached to a vacuum hose that provides motive power to drive the sander and for removing sanding dust off of a wall surface that is pulled into a collection canister.  
           [0003]    2. Prior Art  
           [0004]    The present invention is in improvements to a vacuum driven sander as embodied in U.S. Pat. No. 6,347,985 issued to the present inventor. The vacuum driven sander of the &#39;985 patent constitutes a marked improvement over earlier sanders. With some examples of such earlier sanding devices are shown, in U.S. utility patents to Brenner No. 3,722,147; to Mehrer No. 4,062,152; to Marton No. 4,184,291; to Rodowsky, Jr. et al. No. 4,399,683; to Romine No. 4,697,389; to Paterson No. 5,007,206; to Sanchez, et al. No. 5,193,313; to Brown No. 5,283,988; to Matchuk No. 5,605,600; and to Brown No. 5,624,305. Also, the vacuum driven sander of the &#39;985 patent is unique and distinct from certain other electric motor driven devices that connect through a hose to a vacuum or suction device like those shown in Davies U.S. Pat. No. 1,800,341; to Jones No. 3,468,076; to Hutchins No. 3,785,092; to Hutchins No. 4,052,420; to Matechuk No. 4,782,632; to Flacheneck, et al. No. 4,905,420; to Fushiya et al. No. 5,018,314; to Takada No. 5,185,544; to Chu et al. No. 5,228,224; to Smith No. 5,384,984; to Hutchins No. 5,582,541; to Heidelberger No. 5,595,530; to Everts, et al. No. 5,637,034; and in Design Patents to Taylor No. Des. 375,885; to Gildersleeve et al. No. Des. 392,861; to Fushiya et al. No. Des. 326,398; to Morey et al. No. Des 351,976; and to Stiles No. Des. 353,313. None of which earlier sanding devices prior to that of the &#39;985 patent of the inventor, however, included a vacuum driven oscillating sanding disk that provided for the efficient and reliable removal of sanded particles from the work surface through an attached vacuum hose.  
           [0005]    Somewhat similar to the vacuum driven sander of the &#39;985 patent are U. S. Patents to Brenner No. 3,722,147; to Rodowsky, Jr. et al. No. 4,399,638; and to Marton No. 4,616,449, that show sanding devices where an oscillating plate mounts a sheet of sand paper, is air driven by a vacuum flow and also provides for removal of sanding dust off from a work surface to pass that collected dust through a vacuum hose into a collection container. However, while the patent to Rodowsky, Jr. et al., No. 4,399,638 provides a turbine blade that is turned by a vacuum flow to operate an oscillating plate whereto a section of sanding material is attached, calls for pulling that sanded dust through the turbine bearing, thereby greatly limiting bearing life. Which inherent flaw was recognized and corrected in the &#39;985 patent of the inventor.  
           [0006]    The &#39;985 patent of the inventor provides a vacuum driven sander where the turbine bearings are protected from exposure to the dust laden vacuum flow and, as further unique features, includes a balanced split-air intake that providing a balanced driving force to the turbine blades, drawing essentially equal air flows from both sides of the sander and also improves upon the entrainment of dust and contaminants in the air flows as are passed through the sander. Further, the turbine of the &#39;985 patent is itself an improvement over earlier devices in that it incorporates a split design where the top and bottom turbine sections are not symmetrical, with the lower turbine section having the greater height to allow the bearings and bearing supports to be conveniently fitted inside the turbine mounting section in the sander housing, providing a turbine housing profile that is shorter than former sanders turbines and has a lower center of gravity as compared to earlier sanders.  
           [0007]    The &#39;985 patent also provided an improved pole coupling assembly that allows the angle of a pole whereon the vacuum driven sander is mounted to be changed to accommodate a selected sander top surface to a wall allowing the body to be moved up and down over a wall, but does not provide a universal type joint arrangement that allows the sander body to be easily tilted both up and down and side to side relative to its mounting pole. While a ball coupling of a pole end to head is shown in U.S. Pat. No. 5,144,774 to Conboy, the coupling is not a universal type coupling like that of the invention. Nor does the &#39;985 patent provide for dissipation of a static electrical charge as the contact of an oscillating sander surface creates, and further fails to provide for tightly locking the sander turbine onto a top end of a bearing assembly that supports the turbine and its connected eccentric. Which deficiencies in the &#39;985 patent are addressed and solved by the improvements of the present invention.  
         SUMMARY OF THE INVENTION  
         [0008]    It is a principal object of the present invention to provide an improved vacuum air driven turbine operated sander that includes a coupling arrangement that allows the sander head to be pivoted freely, both in the vertical and horizontal axis, as it is moved across a wall.  
           [0009]    Another object of the present invention is to provide for the elimination of a buildup of a static electricity charge as is produced during sander operations from contact of the sanding face with a wall surface.  
           [0010]    Another object of the present invention is to provide a bolt and nut locking arrangement for tightly coupling a sander head turbine onto a bearing assembly, allowing for setting and holding a desired torque on the coupling, providing improved sander functioning.  
           [0011]    Another object of the present invention is to provide, as the mechanism for allowing the sander head to be moved in both the vertical and horizontal axis across a sander pole end is a universal joint type joint arranged on a hollow bent pole mount fitted between the sander housing head and pole whereby the head can be easily and conveniently tilted side to side and up and down relative to the pole end without a disruption of a seal between the head and pole end as could compromise a vacuum air flow through the pole.  
           [0012]    Still another object of the present invention is to provide a vacuum sander head and pole arrangement whereby a static electric charge as builds up on the sander housing and pole during sanding operations is directed through a static charge eliminator that extends from the sander head and into the pole wherethrough the vacuum flow passes, dissipating that charge into the passing flow.  
           [0013]    Still another object of the present invention is to provide a vacuum sander turbine and bearing mount where the turbine, bearing assembly and eccentric are held together with a nut and bolt type connection arrangement to hold the components together at a set torque value.  
           [0014]    Still another object of the present invention is to provide a vacuum driven sander that is light in weight and is convenient to connect to a vacuum hose, with the vacuum air flow to both reliably turn an oscillating plate or pad of the sander head and to draw collected dust from the sander head through an open pole for passage to a collection container.  
           [0015]    The present invention is in an improved vacuum air flow air driven oscillating sander and sander pole, with the sander head including a bent hollow pole mount that connects through a universal type joint to an end of a hollow pole that is connected to a hose to pass a vacuum air flow therethrough and into a collection container. The bent hollow pole mount is preferably a tube having a ball end section formed on one end and is bent at less than a right angle a distance therealong from which ball section end. Lugs are formed to extend outwardly from opposite sides of which ball end section that are for fitting into ears formed to extend outward and parallel from a top edge of a curved collar lower portion that is to fit over, as a seat, the ball end section of the bent hollow pole mount. The curved collar ears each have a hole therethrough that align to individually receive each of the pair of ball end section lugs, forming a pivot coupling therebetween. Further, the curved collar itself includes a pair of stub axles that each project outwardly from an opposite side of the curved collar upper end section, with each stub axle and lug, respectively, being spaced ninety degrees apart. The improved vacuum sander housing includes a dome that is externally threaded, includes a vertical port or opening therethrough and flat top surfaces wherein spaced radial cavities are formed around which port or opening to receive the stub axles. The spaced radial pivot cavities individually receive each of the pair of stub axles fitted therein and a collar having a center opening is turned thereover to contain the stub axles in the selected pivot cavities, forming pivot mountings of which stub axles. So arranged, the lugs mounted to the collar ears and the stub axles fitted in the spaced radial cavities provide a universal joint that allows the sander head to pivot up and down pivot and across the pole end.  
           [0016]    In operation, a static electricity charge is built up in the sander body and travels into the pole during sander operations by contract of the sanding surface and wall surfaces, This charge is dissipated by an inclusion of a conductive wire connected at one end to an electrical contact formed in the sander bent hollow pole mount and is fitted into the pole, extending along its length. The static electric charge as is built up thereon during sanding operation is dissipated into the vacuum flow rather than building up on the sander and pole surfaces to be discharged through an operator.  
           [0017]    For providing a secure mounting of the sander eccentric to a turbine bearing assembly and the turbine, the invention includes a threaded rod secured to extend out from a top surface of the eccentric that is fitted through the turbine bearing assembly and passes through the turbine top to receive a locking nut fitted and turned thereover. The locking nut is turned to a determined torque value against the turbine top surface, sandwiching the bearing assembly between the turbine and eccentric, and, after the tool is operated to brake it in, the nut is re-torqued to a final set torque value.  
           [0018]    Still other benefits and advantages of the invention will become apparent to those skilled in the art to which it pertains upon a reading and understanding of the following detailed specification.  
       
    
    
     DESCRIPTION OF THE DRAWINGS  
       [0019]    The invention may take physical form in certain parts and arrangements of parts, and a preferred embodiment of which will be described in detail in this specification and illustrated in the accompanying drawings which form a part hereof:  
         [0020]    [0020]FIG. 1 is a perspective view taken from a left side and front of a vacuum sander of the invention, showing a bent hollow pole mount extending out from a sander housing top section collar and cap and showing a pole end mounted to the bent hollow pole mount that has been broken away and exposes a static electricity charge dissipater within the pole;  
         [0021]    [0021]FIG. 2 shows a side elevation exploded view of the vacuum sander of FIG. 1, with the pole broken away, exposing the static electricity charge dissipater extending from its electrical coupling to the top end of the bent hollow pole mount, with the pole end shown as including equal spaced lugs and stub axles projecting outwardly from its ball end base and a collar as a universal coupling and showing a threaded rod extending out from the top of the eccentric that is passed through the lower bearing, turbine housing, upper bearing and turbine to receive a lock nut turned thereover as the turbine torque mounting to the sander bearing assembly and eccentric;  
         [0022]    [0022]FIG. 3 is a top plan sectional view taken along the line  2 - 2  of FIG. 2 of the turbine showing a lock nut turned over the threaded rod end against the edge of the turbine center hole;  
         [0023]    [0023]FIG. 4 is a front elevation sectional view taken along the line  4 - 4  of FIG. 1; and  
         [0024]    [0024]FIG. 5 is an exploded view of the vacuum sander of FIG. 1 showing the collar mounted onto the sander top to include radially spaced slots formed therein that are to receive the stub axles of a collar of the bent hollow pole mount fitted therein as a vertical pivot mounting of the pole to the sander head, and showing spaced lugs extending outwardly from the sides of the ball end of the bent hollow pole mount that are fitted, as pivots into ears of the collar, allowing for tilting the sander head across the pole end, with the stub axles and lugs providing a universal joint that is contained to the sander top by a cap turned over the threaded collar exterior surface that is shown exploded from the collar. 
     
    
     DETAILED DESCRIPTION  
       [0025]    The invention is herein described with reference to a preferred embodiment shown in the accompanying drawings, with FIG. 1 showing a front elevation perspective view of the low profile vacuum driven sander  10  of the invention, hereinafter referred to as sander. As shown in the Figs., the sander  10  includes a housing  11 , having front, rear and side walls  13   a ,  13   b ,  14   a , and  14   b , respectively, extending at right angles downwardly from a housing top edge, forming an inverted narrow rectangular box configuration having, as shown in FIG. 4 an open bottom  15 . A coupling collar assembly  16  that is open therethrough is shown in FIGS. 1, 3 and  4 , fitted into the center of the top  12  that includes, as shown in FIGS. 2 and 5, a pair of turbine ducts  17   a  and  17   b  that are shown as flat raised sections that extend oppositely from steps  18   a  and  18   b  to an opening in the center of the flat top  12 , and open into the coupling collar assembly, as shown in FIG. 4, to serve as ducts to pass and direct a turbine exhaust air flow through the collar assembly that enters a hollow bent tube  23  that is preferably bent at an angle of approximately twenty two and one half (22 ½) degrees, and passes the vacuum flow therethrough that travels into a pole  90 .  
         [0026]    The hollow bent tube  23 , as shown in FIGS. 2, 4 and  5 , has a ball section  22  lower end that mounts to a collar  24 . The collar  24  upper surface is open to fit and slide over the ball section  22  lower end, includes a curved inner surface  24   a  and has a ball section shaped outer surface  24   b  having ears  25  formed thereto that extend essentially parallel to one another from the collar upper edge. Which ears each have holes  25   a  formed therethrough that align with one another and are each to receive a lug  26  of a pair of lugs  26  that are formed to extend outwardly, from opposite sides, of the hollow bent tube  23  ball section  22 . So arranged, the lugs  26  are fitted into the ears  25  holes  25   a  as a pivot mounting that allows for a pivoting of the hollow bent tube  23 , at its ball section end  22 , across the collar  24 , moving the hollow bent tube  23  across the collar  24  The collar  24  includes a pair of stub axles  27  for mounting the hollow bent tube  23  onto the sander housing  11  that extend from opposite sides of the collar  24  outer surface, and are on line with one another. To provide which coupling, the respective stub axles  27  are positioned in the coupling collar assembly  16  that extends upwardly from between the turbine ducts  17   a  and  17   b , as shown best in FIGS. 1 and 5. Which turbine ducts  17   a  and  17   b  are shown as oval sections formed that are in the housing  11  top  12 , on opposite sides of a coupling collar assembly  16  cylinder  28  base  28   a . The cylinder  28 , as shown best in FIG. 5, has a center hole  29  that opens into the turbine ducts  17   a  and  17   b , and a lower edge  29   a  of that has a concave curved surface that serves as a seat that the end of the collar  24  ball section shaped outer surface  24   a  fits against, with the combination of concave curved surface and ball section shaped outer surface providing a ball and seat coupling of the hollow bent tube  23  to the sander coupling collar assembly  16 . For which collar  24  equal spaced radial slots  30  are formed in the cylinder  28 , extending radially outwardly from around the hole  29 , that are for individually receiving each of the stub axles  27 . The stub axles are contained in the individual radial slots  30  by turning a cap  31  thereover that is internally threaded at  32 , as shown in FIG. 5, for turning over outer threads  28   b  of cylinder  28 . With the stub axles  27  contained by cap  31  within individual radial slots  30  a pivot mounting of the sander body  11  onto the hollow bent tube  23  is provided that allows the sander housing to be pivoted across the hollow bent tube  23  and collar  24 . For pivoting of the sander body  1 I 1  up and down on the hollow bent tube  23  the lugs  26 , that extend outwardly from the hollow bent tube ball section  22 , are fitted into collar  24  ears  25  holes  25   a , providing the pivot coupling. So arranged, the pivot coupling of the hollow bent tube ball section  22  provides a ball and seat coupling to collar  24 . Which collar  24  has an upper or top end that has curved surface  24   a  to function as a ball section that is for fitting onto the cylinder  28  hole  29  curved edge  29   a , also functioning as a ball and seat mounting. The ball and seat mountings, as set out above, are to contain, with minimum leakage, a vacuum air flow passed therethrough. So arranged, the lugs  26  and stub axles  27  and their mountings, respectively to the collar ears  25  and cylinder cavities  30 , shown in FIG. 5 as individual half cylindrical sections, provide a universal joint that allows the sander housing  11  to be pivoted up and down and across the hollow bent tube  23  ball section end  22 . To maintain which coupling, the hollow bent tube  23  opposite of top end  23   a  is treaded to receive an interior threaded collar  91  of a pole  90 . An operator, holding pole  90 , can conveniently pivot the sander head  11  as it is moved up and down and back and forth across a wall surface.  
         [0027]    Shown in FIG. 4, the turbine ducts  17   a  and  17   b  direct the turbine exhaust flow into a dome  20  that then passes the flow into the hollow bent tube  23 , wherefrom it is exhausted through the connected pole  90  to travel into a vacuum hose, not shown, that passes the flow into a collection container, not shown. As set out above, the stub axles  27  mounted in cylindrical  28  cavities  30  provide a pivot coupling that allows for the sander body  11  to be pivoted across the hollow bent tube  23  end, and, additionally, an operator, by a selection of a particular pair of cavities  30  to receive the stub axles  27 , can select a desired mounting angle of the sander head  11  to the hollow bent tube  23  and connected pole  90 . So arranged, the sander body  11  position or attitude to the end of pole  90  is selectively positionable relative to the hollow bent tube  23  to facilitate the sander being moved up and down or side to side, as the operator determines.  
         [0028]    Sander head  11  positioning, however, is preferably not rigid in that the diameter of hole  31   a  through the cap  31  is selected to be somewhat larger or greater the hollow bent tube  23  diameter, as shown in FIGS. 1, 4 and  5 , that allows for some movement between which sander body  11  and bent tube  23 , as during use of the sander, with the loose fit of the cap hole  31  a to the hollow bent tube  23  outer surface to minimize a likelihood of damage to the coupling should the sander “stick” to the wall surface. With a likelihood of such damage from sander “sticking” being further mitigated by the universal coupling of the sander housing  11  to the hollow bent tube  23  ball section  22  end., as described above. The sander  10  is equipped with a sanding pad  45 , as shown best in FIG. 2, that, as shown in FIG. 4, is of a lesser length and width than the distances between the inner surfaces of housing end walls  14   a  and  14   b  and front and rear walls  13   a  and  13   b leaving a space therebetween to allow for passage of a vacuum air flow that is pulled therearound. Which vacuum air flow will both turn a turbine  63  and will pick up sanding dust off of the surface being sanding, entraining that dust in the vacuum air flow, as discussed below. To provide sanding, the sanding pad  45  is fitted with a section of sanding material  46 , as shown in FIG. 4, that is maintained thereto, preferably with Velcro type fasteners, adhesive sections, or the like, and with the sanding pad  45  oscillated through an eccentric  72  that is turned by turning of the turbine  63 , as set out below.  
         [0029]    The sanding pad  45 , as shown best in FIGS. 2 and 4, includes a stiff flat rectangular plate  47  that has a front or outer face  47   a  and is arranged for releasably mounting sheets of sand paper, or other sanding material, thereover. The rectangular plate  47  includes identical spiders  48  that each have a head end  49  wherein a center hole is formed are each mounted to the corner of a rear or inner face  47   b , as shown best in FIG. 2. The spiders  48  each include like spaced straight legs  50  that extend outwardly from around the head end  49 , and the spiders opposite ends are secured to the plate inner face  47   b  surface. The straight legs  50  are preferably formed from a semi-rigid plastic, or other appropriate light weight stiff material, to flex and allow the sanding pad  45  to oscillate, moving orbitally while supporting the pad against collapse when pressure is applied to force the sanding pad against a surface to be sanded.  
         [0030]    For mounting the sanding pad  45  to the sander body  11 , as shown in FIG. 2, screws  51  are each aligned and fitted through holes that are formed through the sanding pad  45 , preferably at each of the pad comers, and pass through the individual spider  48 . The holes each align with a hole  49   a  that is formed through a spider end  49 , as shown in broken lines in FIG. 4. The screws  51  are individually turned into a pier  52  that is formed in, to project outwardly from, the bottom surface  12   a  of the flat top  12 , as shown also in FIG. 2. So arranged, with each of the spiders  48  connected at its head end  49  to a pier  52 , the sanding pad  45  is suspended on the spider legs  50  allowing the sanding pad  45  to oscillate orbitally when moved by operation of the turbine  63  turning an eccentric  72 , as set out below. Which connection of the sanding pad  45  spiders to the undersurface  12   a  of the flat top  12  is a last step in the assembly process where the flat top  12  and sanding pad are fitted to the housing  11 , following the installation of the turbine and bearing assembly in the housing  11 , as set out herein below.  
         [0031]    The housing  11  is preferably formed, as by molding or like methods, to include air intakes or air inlet cavities  55  that are arranged in both ends of the housing  11 , and direct inlet air that has passed around the sanding pad  45  into inwardly sloping sections within the housing  11 , with the flows vented into a turbine chamber  56 , striking blades  80  of the turbine  63 . The inlet flows are of approximately the same volume, providing a balanced driving force to turn the turbine  63 . The air inlet cavities  55  are each formed in the housing, along with the turbine chamber  56 , that, as shown best in FIG. 4, is a cavity formed around a center stanchion  57  and projects upwardly from a chamber floor  58 , is formed across the housing interior and is spaced upwardly from where the sanding pad  45  is positioned. Which housing interior chamber floor  58  has the air inlet cavities  55  and a center hole  59  formed therein that an eccentric  72  is fitted in, as set out below.  
         [0032]    The stanchion  57 , as shown in FIGS. 2 and 4, has an inner turbine chamber wall  60 , that is flat across its top surface  61  and includes a bearing cavity  62  formed through that top surface that extends downwardly to the chamber floor  58  with a center hole  59 . The bearing cavity  62  is to receiving a pair of like upper and lower turbine bearings  64  and  65  of turbine  63  that align to pass a threaded turbine mounting axle  66  extends therethrough from a top  73  of eccentric  72 . To maintain which upper and lower turbine bearings  64  and  65 , respectively, the bearing cavity  62 , as shown in FIG. 4 is stepped inwardly at  62   a  and  62   b , providing a ledge  62   c  therebetween, that is for maintaining bearing spacing, and whose opposite ends support each of the turbine bearings.  
         [0033]    The turbine mounting axle  66 , as shown in FIGS. 2 and 4, is threaded at its top end  66   a  that is passed through the turbine  63  to receive a lock nut  67  turned thereover. Which lock nut  67  preferably includes an interior locking washer arrangement wherethrough the threaded turbine mounting axle  66  end  66   a  is turned, with the washer to resist back turning of the nut. allowing an operator to turn the nut  67  to a desired torque that will not loosen during turbine rotation. So arranged, the eccentric  72  top surface  73  is held tightly against a lower surface of lower turbine bearing  65  that is, in turn, held at its top surface against the lower surface of the bearing cavity  62  ledge  62   c , with the upper bearing  64  lower surface  71  held tightly against the upper surface of the bearing cavity  62  ledge  62   c , and with a turbine  63  lower section held tightly onto the upper bearing  64  top surface turning nut  67  turned on the end  66   a  of the threaded turbine mounting axle  66  into tight fitting engagement with a top section of the turbine  63  top section  70 , completes the assembly of the stack of the eccentric  72 , bearings  64  and  65  and turbine  63 . In practice, a torque of a sufficient value to accomplish a tight coupling together of the stack components is applied to the lock nut  67 . Then, after a short period of time of turbine  63  turning, the lock nut is re-tightened to a final torque of approximately five (5) inch pounds. Which torque value the nut  67  maintains during operations, completing the tool assembly.  
         [0034]    As set out above, the threaded turbine mounting axle  66  extends from a top  73  of eccentric  72  that includes an orbit axle  74 . The orbit axle  74  is slightly off set from the axis of the turbine mount axle  66  and is journaled to turn in a cup  76  of a pier  75  that, as shown best in FIG. 4, is formed onto the inner surface of the sander stiff rectangular plate  47 . Which pier  75  is formed as a raised section and includes the cup  76  formed therein to be slightly off-set from the disk  74  center. The orbit axle  74  is fitted into a bearing  77  that is maintained the cup  76  of the sanding pad  45 . So arranged, turning of the turbine  63  turns the turbine mounting axle  66  that is coupled to the eccentric  72  top end  73 , and turns the eccentric axle pin  74 . Which eccentric axle pin  74  is journaled in a sanding pad  45  bearing  77  that is mounted in cup  76  of the pier  75 . An oscillating motion is thereby imparted into the sanding pad, moving it in an orbital path to, in turn, provide an orbital movement to a sheet of sand material attached to the sander stiff rectangular plate  47  outer surface that is, in turn, in contact with a sheet rock wall surface, sanding that surface.  
         [0035]    The turbine  63 , like the turbine of the inventor&#39;s earlier &#39;985 patent, is preferably a split design, formed in two sections, a lower of which sections has a greater height than the height of the top section. So arranged, the bearing assembly axle bearings  64  and  65  can be easily installed in the bearing cavity  62 , with the top axle bearing  64  being fitted into the top end of the bearing cavity  62  sliding along the stepped section  62   a  to come to rest on the top lip of the ledge  62   c . The lower bearing  65  is fitted through the housing  11  open bottom center hole  59 , traveling into the bearing cavity, sliding along the lower stepped section  62   b  to where its edge engages the bottom lip of ledge  62   c . The turbine  63  is fitted, as shown in FIG. 4, through the open top of housing  11  to rest on the top of the top surface  61  of the stanchion  57 . The sanding pad  45  bearing  77  is the mounting cup  76  of the pier  75  that extends upwardly from the sanding pad inner face  47   b , and, with the eccentric axle pin  74  fitted into which bearing  77 , the sanding pad  45  and top  12  are installed to the body  11 , as set out above.  
         [0036]    The turbine  63  is preferably formed from a hard plastic material, metal, or the like, and the described upper and lower turbine halves are joined together as by an adhesive bonding, by welding, brazing, or the like, with the assembly then fitted, as shown best in FIG. 4, into the housing turbine chamber  56 . Blades  80  of the turbine  63  are spaced apart equal distances and are preferably curved to each receive the inlet vacuum air flow at their forward edges  80   a  that with an air flow traveling inward to the blades hub ends. The preferred curve of which blades  80  is shown best in FIG. 3. The spacing distance between which blades  80  is shown as reducing from their inlet ends  80   a  to their exhaust ends.  
         [0037]    In practice, an inlet vacuum flow is pulled around the sanding pad  45  and passes, as a balanced air flow, through the air inlet cavities  55  and into the turbine chamber  56  wherein the turbine  63  is journaled to upper and lower bearings  64  and  65 . The turbine blades  80  each receive the air flow and react thereto by turning, to turn also the eccentric  72  and its eccentric axle pin  74  that itself turns in bearing  77 . Which bearing  77  is fitted in mounting cup  76  and moves, in turn, the sanding pad  45  in an orbital path, sanding a surface. In operation, the inlet vacuum air flow picks up sanding dust off from a working surface during its passage around the sanding pad  45 , and then passes through turbine ducts  17   a  and  17   b , driving the turbine  63 . Which vacuum flow contains entrained dust collected therein in that passage, is then exhausted through the hollow bent tube  23 , and into and through the pole  90 , to pass into a vacuum hose that vents into a collection container.  
         [0038]    The vacuum air flow is contaminated with sanding dust that is entrained therein off from the sanded surface and travels around the sanding pad  45  edges. A portion of such dust, in earlier sanders, has tended to find its way into the bearing assembly to, in short order, contaminate the bearings, greatly curtailing turbine turning, and severely limiting the useful life of such sander. This problem was recognized and corrected in the &#39;985 patent of the inventor who provided for securely closing and sealing the bearing cavity  62  by the arrangement of the fitting of the turbine axle  66  head end  67  in the upper turbine half plate  70   a  collar  69  and turning of the axle threaded end  68  into the eccentric top end  73 , providing a tight clamping together of the upper and lower turbine halves plates  70  and  71 . The upper turbine bearing  64  is thereby tightly clamped between the undersurface of the lower turbine half plate  71  and the upper edge of the stepped section  62 c of the bearing cavity  62 . So arranged, the lower turbine bearing  65  top edge is clamped against the lower edge of the stepped section  62   c , and has its lower edge held against the eccentric disk  64  top surface. Further, as a significant feature of the invention of the &#39;985 patent, dust is precluded from traveling into the bearing cavity  62 , a formation of a passage through the housing that extends from an opening in the bearing cavity  62 , and slopes downwardly through the stanchion  57 , becomes a horizontal passage through the chamber floor  58 , and opens through the housing  11  front  13   a  at opening  86 , as shown in FIGS. 1 and 5. In operation, the vacuum inlet flow through into the sander  10  creates less than ambient conditions within housing  11  and the bearing cavity  62 , that causes an air flow to be pulled from without the sander and through an opening  86  in the housing wall  13   a  and ultimately travels into the bearing cavity  62 . A positive pressure is thereby created within the bearing cavity  62  that prevents dust as contained in the vacuum flow from traveling into the bearing cavity, with that flow also providing a cooling air flow that travels over the bearings  64  and  65 . Additionally, the passage can be used to pass oil, fed as drops into the opening  86 , that will travel into the bearing cavity, and lubricate the turbine bearings  64  and  65 . Passing of a clean air flow from without the sander into the bearing cavity  62  through passage along with a periodic introduction of oil through opening  86 , provides the sander  10  with a long and useful life.  
         [0039]    The collar  91  of pole  90 , as shown in FIGS. 1, 2 and  4  and  5 , is internally threaded at  91   a , as shown in FIG. 4, to turn over a threaded end  23   a  of hollow bent tube  23 . A static electricity ground connector, is shown in FIG. 2, as a male bayonet electrical connector  85  that connects to a wire  85   a  to, as shown in broken lines, extends therefrom and is molded into the hollow bent tube. Shown in FIGS. 2 and 5, the male bayonet electrical connector  85  extends from the lip of the threaded end  23   a  of hollow bent tube  23  to pass within the pole collar  91  when it is turned over the hollow bent tube  23  threaded end  23   a . Prior to which turning of the pole collar  91  onto the threaded end  23   a  of hollow bent tube  23 . A female bayonet type connector  92  is shown fitted onto the male connector  85 , completing an electrical connection therebetween. The female bayonet type connector  92 , as shown in FIGS. 2 and 5, is connected onto an end of a static electricity discharge wire  93  that is preferably the length of, for fitting into the pole  90  to extend within the pole, with the exhaust vacuum air flow to pass over the static electricity discharge wire  93  as it travel along and out of the pole  90 . In sander operations, a static electric charge builds up on the sander during sanding operations that is produced by the contact of the orbiting sanding surface on a wall surface, and this charge tends to build up over the sander body and pole surfaces. Such charge can be discharged through an operator when that operator comes in contact with a ground, giving that operator an unpleasant shock.. The presence of the static electricity discharge wire  93  that is ultimately connected to the sander housing and extends within the pole  90 , approximately the length thereof, provides for a dissipation of that built up charge off from the sander and pole surfaces, and passes such built up charge along the length of the discharge wire  93  into the vacuum flow, precluding a buildup of a charge thereon that could flow through an operator to ground.  
         [0040]    In practice, the pole  90 , as shown, is preferably an inner pole whereover an outer pole, not shown is telescoped. In which arrangement, the outer pole preferably includes a locking collar, not shown, that is secured to turn across a lower end thereof that it telescoped over the inner pole  90 . By turning which locking collar, the outer pole end is urged against the inner pole  90  end, locking the inner and outer poles together. So arranged, a lengthened sander pole is provided, with the outer pole end that is opposite to the locking collar end to include a coupling for connection to a vacuum hose, not shown.  
         [0041]    A preferred embodiment of my invention an improved vacuum driven sander has been shown and described above. It will, however, be apparent to one skilled in the art that the above described embodiment may incorporate changes and modifications without departing from the general scope of the invention. Which invention. it should be understood, is intended to include all such modifications and alterations in so far as they come within the scope of the appended claims and/or a reasonable equivalence thereof.