Patent Publication Number: US-6699103-B1

Title: Mower reel blade grinding device

Description:
BACKGROUND OF THE INVENTION 
     The present invention, relates to grinding systems, and more specifically to methods and apparatus for automatically sharpening blades on cutting reels of lawn mowers. 
     Commercial reel-type lawn mowers typically utilize cutting reels that have helical blades. The cutting reels must be maintained regularly to assure proper operation. Part of such maintenance involves sharpening the blades and sharpening and/or adjusting the bed knives. The sharpening process typically involves two steps. The first step involves spin grinding the tips or radially outer ends of the blades in order to true the reel back to cylindrical shape and sharpen the cutting edge. The second step involves relief grinding the trailing edge of each blade. 
     U.S. Pat. No. 5,321,912 to Neary et al. teaches a grinding system for spin and relief grinding cutting reels of commercial reel-type lawn mowers. The Neary et al. grinding system utilizes a common rotating drive shaft to rotate a spin grinding wheel and a relief grinding wheel. Both grinding wheels are separately axially slideably mounted on the common rotating shaft, which is generally parallel to the axis of the cutting reel to be ground. While the Neary et al. system offers the common rotating shaft, which is a desirable feature to many grinder operators, it lacks a means of auto indexing from blade to blade. Thus, the Neary et al. grinding system requires an operator to manually cycle each blade through the relief grinding process. This is labor intensive and time consuming. In addition, the fork assemblies  32  on either side of the grinding wheels necessarily wear from sliding contact with the grinding wheels and/or grinding shaft  18 , and they provide poor positioning stability for the grinding wheels. 
     U.S. Pat. No. 6,010,394 to Dieck et al. teaches a grinding system for spin and relief grinding cutting reels of commercial lawn mowers. The Dieck et al. grinding system utilizes a movable grinding head, which includes a grinding wheel and a motor mounted on a carriage. The grinding head is slideably mounted on rails that are generally parallel to the axis of the cutting reel. The Dieck et al. system offers an auto indexing system for automatically indexing from blade to blade. 
     There is a need in the art for a grinding system that allows auto indexing on a grinding system utilizing a common rotational shaft, reduces part friction and wear, and improves grinding accuracy. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention, in one embodiment, is a device for relief grinding a blade having a radially outer edge of an elongated length and first and second faces, with the first and second faces extending generally radially from a reel axis. The device includes a rotatable grinding shaft, a grinding wheel, a grinding wheel guide assembly, a guide finger, and a first non-sliding stabilizer. 
     The rotatable grinding shaft defines a grinding wheel axis. The grinding wheel is rotatable with and axially slideable along the grinding shaft to follow the elongated length of the blade. The grinding wheel includes a hub with a first bearing surface. The grinding wheel guide assembly is mounted for motion parallel to the grinding wheel axis on at least one rail that extends the elongated length of the blade and is substantially parallel to the grinding wheel axis. The guide finger is adjustably supported on the grinding wheel guide assembly for contacting one face of the blade during grinding and holding the blade in position for relief grinding. The first non-sliding stabilizer bearing is supported on the grinding wheel guide assembly for bearing contact with the first bearing surface. The first stabilizer bearing is oriented to apply to the first bearing surface forces applied to the grinding wheel guide assembly that include a component parallel to the grinding wheel axis. 
     The present invention, in another embodiment, is a device for relief grinding a blade having a radially outer edge of an elongated length and first and second faces, with the first and second faces extending generally radially from a reel axis. The device includes a rotatable grinding shaft, a grinding wheel, a grinding wheel guide assembly, a guide finger, and a first non-sliding stabilizer bearing. 
     The rotatable grinding shaft defines a grinding wheel axis. The grinding wheel is rotatable with and axially slideable along the grinding shaft to follow the elongated length of the blade. The grinding wheel includes a hub with a stabilizer bearing surface. The grinding wheel guide assembly is mounted for motion parallel to the grinding wheel axis on at least one rail that extends the elongated length of the blade and is substantially parallel to the grinding wheel axis. The guide finger is adjustably supported on the grinding wheel guide assembly for contacting one face of the blade during grinding and holding the blade in position for relief grinding. The first non-sliding stabilizer bearing is interposed for bearing contact between the grinding wheel guide assembly and the stabilizer bearing surface. The first stabilizer bearing is oriented to apply to the stabilizer bearing surface forces applied to the grinding wheel guide assembly including both a component parallel to the grinding wheel axis and a component perpendicular to the grinding wheel axis. 
     While multiple embodiments are disclosed, still other embodiments of the present invention will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the invention. As will be realized, the invention is capable of modifications in various obvious aspects, all without departing from the spirit and scope of the present invention. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an isometric view of a relief grinding device having a rotating shaft for rotating a grinding wheel assembly of the device. 
     FIG. 2 is the same isometric view of FIG. 1, except the rotating shaft has been removed for clarity. 
     FIG. 3 is a left side elevation view of the device located within the surrounding framework of the overall grinding system with a cutting reel shown in phantom and wherein the line of sight runs parallel with the axis of the rotating shaft. 
     FIG. 4 is a detail view of the same elevation view as depicted in FIG.  3 . 
     FIG. 5 is a front elevation view of the device wherein the line of sight runs towards the first vertical plate of the stabilizer assembly, wherein the first and second vertical plates of the stabilizer assembly have been made invisible to reveal aspects of the device that are hidden in the preceding FIGS. 
     FIG. 6 is a plan view of the device with a blade of a cutting reel shown in phantom and abutting a guide finger, an index finger tip and a grinding wheel. 
     FIG. 7 is an exploded isometric view of the device. 
     FIG. 8 a  is an isometric view of an alternative embodiment of the device, which utilizes profiled holes for receiving a profiled rail. 
     FIG. 8 b  is an isometric view of the profiled rails for use with the profiled holes illustrated in FIG. 8 a.    
     FIG. 9 a  is an isometric view of another alternative embodiment of the device, which utilizes another type of profiled rail. 
     FIG. 9 b  is a cross-sectional elevation view taken along section line AA of the right profiled rail of the alternative embodiment depicted in FIG. 9 a , wherein the rail is in its receiving hole within the device, and the hole has rollers that rollably interface with the faces of the profiled rail. 
     FIG. 10 shows a plan view of an alternative embodiment having a rolling bearing means for resisting both the torsional and bending moments. 
     FIG. 11 shows a plan view of another alternative embodiment having a rolling bearing means for resisting both the torsional and bending moments. 
    
    
     DETAILED DESCRIPTION 
     FIG. 1 shows an isometric view of a relief grinding device  5  for relief grinding helical blades on cutting reels of lawn mowers. An advantageous aspect of the grinding device  5  is that it allows a grinding system utilizing a common rotational shaft and mechanism to auto index the blades of the cutting reel undergoing a relief grinding procedure. 
     As shown in FIG. 1, the device  5  includes a grinding wheel assembly  10 , a rotating grinding shaft  15 , two rails  20   a ,  20   b , and a grinding wheel guide assembly  25  mounted on the rails  20   a ,  20   b . The grinding wheel assembly  10  comprises a grinding wheel  30  mounted on a hub  35 . The guide assembly  25  includes a traveling block  40 , an indexing assembly  45 , and a stabilizer assembly  50 . The shaft  15  has a keyway  52  that runs the length of the shaft  15  and generally parallel to the shaft&#39;s rotational axis, which is axis A in FIG.  1 . 
     As will be explained in greater detail later in this specification, during a relief grinding operation, the shaft  15  causes the grinding wheel assembly  10  to rotate about axis A, which causes the grinding wheel  30  to spin against a cutting reel blade that is mounted above the grinding wheel  30  generally parallel to axis A. The guide assembly  25  travels along the rails  20   a ,  20   b , moving the grinding wheel assembly  10  axially along the shaft  15 , which causes the spinning grinding wheel  30  to travel the length of the blade. 
     The stabilizer assembly  50  resists forces exerted on the indexing assembly  45  by the blade, which is biased against the indexing assembly  45 . Thus, the positioning of the indexing assembly  45  relative to the blade, grinding wheel  30 , and axis A is maintained within tight tolerances. 
     Once the entire length of the blade has been relief ground, the indexing assembly  45  allows the next cutting reel blade to rotate into position for grinding. In one embodiment of the invention, the grinding wheel  30  must travel down the length of the blade and back before the indexing assembly  45  will allow the next blade to rotate forward. In another embodiment, the grinding wheel  30  must only travel down the length of the blade before the indexing assembly  45  will allow the next blade to rotate forward. 
     FIG. 2 is the same isometric view of FIG. 1, except the shaft  15  has been removed to allow a clearer depiction of the device  5 . Aspects of the hub  35  that can be seen in FIG. 2 include a key  53 , a threaded collar  54  that allows for replacement of the grinding wheel  30 , a cylindrical outer surface  55  and an annular stabilizer flange  60 , which radiates out from the hub&#39;s cylindrical outer surface  55  generally perpendicular to the rotating shaft&#39;s rotational axis A. The key  53  engages the keyway  52  in the shaft  15 . The key  53  may slide along the keyway  52  but cannot rotatably displace relative to the shaft  15 . Thus, the hub  35  is axially slideably mounted on, and rotatably fixed to, the rotating shaft  15 . As will be described below, the cylindrical outer surface  55  of the hub  35  and the annular stabilizer flange  60  serve as a bearing surfaces. 
     The indexing assembly  45  and the stabilizer assembly  50  are mounted on the traveling block  40 , which is slideably mounted on the two rails  20   a ,  20   b . Aspects of the indexing assembly  45  that can be seen in FIG. 2 include a guide finger  65 , a guide finger support  70 , an index finger  75 , an index finger tip  80 , an index finger travel adjustor  85 , a cam follower carrier  90 , a slotted base  95  that has a curved slot  96 , a slot cover  100 , a linear adjustment lock lever  105 , and a radial adjustment lock lever  110 . The slot cover  100  helps to prevent dust and grindings from entering the curved slot  96 . In another embodiment of the invention, where protection from dust or grindings is not required, the slot cover  100  may be replaced with a washer that is centered about the shaft of the radial adjustment lock lever  110  and spans across the curved slot  96 . 
     The stabilizer assembly  50  is bolted to the slotted base  95  by two bolts  115   a ,  115   b . The stabilizer assembly  50 , in one embodiment, serves three purposes. First, as the traveling block  40  is displaced to traverse the length of a blade, elements of the stabilizer assembly  50  act on the annular stabilizer flange  60  of the hub  35 , thereby causing the grinding wheel assembly  10  to displace axially along the rotating shaft  15  (axial thrust action). Second, the stabilizer assembly  50  maintains the indexing assembly  45  in position relative to the grinding wheel  30  by resisting a bending moment along axis A. In other words, the stabilizer assembly  50  prevents the bending moment from displacing the guide finger  65  axially relative to axis A. That is to say the stabilizer assembly  50  prevents the guide finger  65  from deflecting side to side. Finally, the stabilizer assembly  50  maintains the indexing assembly  45  in position relative to the grinding wheel  30  by resisting a torsional moment about axis A. In other words, the stabilizer assembly  50  prevents the torsional moment from displacing the guide finger  65  radially relative to axis A. That is to say the stabilizer assembly  50  prevents the guide finger  65  from deflecting front to back. 
     Both the bending and torsional moments result from forces exerted on the indexing assembly  45  by a blade biasing against the guide finger  65  of the indexing assembly  45  and/or by the grinding wheel  30  forcing the blade against the guide finger  65  of the indexing assembly  45 . In some embodiments of the subject invention (see FIGS. 1-7 and  10 - 11 ), these forces are transferred from the indexing assembly  45  to the rotating shaft  15  via the stabilizing assembly  50 . Since the rotating shaft  15  does not measurably deflect under the magnitude of forces exerted by the biased blade on the indexing assembly  45 , the stabilizer assembly  50  has a rigid foundation on which to prevent deflection of the guide finger  65  relative to axis A. In other embodiments of the subject invention (see FIGS. 8 a ,  8   b ,  9   a ,  9   b ), the force is transferred (in whole or in part) to stiffened profiled rails, which provide the rigid foundation necessary for the guide assembly  25  to prevent deflection of the guide finger  65  relative to axis A. 
     The axis of the rotating shaft (i.e., axis A) does not measurably displace relative to the axis of the cutting reel during the relief grinding process. Therefore, failure to maintain the position of the guide finger  65  relative to axis A during the relief grinding process can result in unacceptable variance in the angle of relief over the length of the blade being relief ground. The embodiments of the subject invention maintain the guide finger  65  sufficiently rigid with respect to axis A so that the forces during grinding do not significantly displace the guide finger  65  axially or radially relative to axis A. 
     As will be explained further in this specification, the stabilizer assembly  50 , in one embodiment, is a device that transfers the grinding wheel assembly  10  along the rotating shaft  15 , resists a bending moment along axis A, and resists a torsional moment about axis A, all while generating minimal part wear and friction between elements of the grinding wheel assembly  10  and the stabilizer assembly  50 . In other words, the stabilizer assembly  50 , in one embodiment, maintains the indexing assembly  45  (i.e., the guide finger  65 ) in position relative to axis A and the grinding wheel  30  while generating minimal part wear and friction between the elements of the grinding wheel assembly  10  and the stabilizer assembly  50 . 
     Aspects of the stabilizer assembly  50  that can be seen in FIG. 2 include: a first vertical plate  120 , which forms a plane that is generally parallel to axis A and has two holes  125   a ,  125   b  for mounting flange rollers  130   a ,  130   b  (shown in subsequent FIGS.); and a second vertical plate  135 , which forms a plane that is generally perpendicular to axis A and has bolts  115   a ,  115   b ,  140   a ,  140   b . Bolt  140   a  secures an upper hub roller  145   a  to the second vertical plate  135 . Likewise, bolt  140   b  secures a lower hub roller  145   b  (shown in subsequent FIGS.) to the second vertical plate  135 . In the embodiment of the invention illustrated, the first and second vertical plates  120 ,  135  form one continuous piece. In another embodiment, the first and second vertical plates  120 ,  135  are two separate pieces that are secured together. 
     To provide an understanding of how the device  5  spatially relates to the overall grinding system and the cutting reel, reference is now made to FIG.  3 . FIG. 3 is a left side elevation view of the device  5  located within the surrounding framework  146  of the overall grinding system  147 . The device  5  is located below a cutting reel  149 , which has a plurality of helical blades  150  with opposed first and second faces and is supported for rotation about the reel axis to sequentially position the blades  150  for grinding by the grinding wheel  30 . 
     FIG. 4 is a detailed left side elevation view of the device  5  as shown in FIG.  3  and illustrates aspects of the stabilizer assembly  50  and the slotted base  95  that are hidden from view in FIG.  2 . As shown in FIG. 4, the upper and lower hub rollers  145   a ,  145   b  are mounted on the second vertical plate  135  via bolts  140   a ,  140   b . The hub rollers  145   a ,  145   b  rollably engage the cylindrical outer surface  55  of the hub  35  as the hub  35  rotates about axis A. The axis of each hub roller  145   a ,  145   b  is generally parallel to axis A. Thus, in one embodiment of the invention, the hub rollers  145   a ,  145   b  allow the stabilizer assembly  50  to maintain the indexing assembly  45  (i.e., the guide finger  65 ) in position relative to the grinding wheel  30  and axis A by resisting a torsional moment about axis A; the hub rollers  145   a ,  145   b  prevent radial displacement of the indexing assembly  45  (i.e., the guide finger  65 ) relative to the grinding wheel  30  and axis A. In other words, by providing non-sliding bearing contact points between the stabilizer assembly  50  and the grinding wheel assembly  10 , the stabilizer assembly  50  helps to maintain the indexing assembly  45  in position relative to the grinding wheel  30  while generating minimal part wear and friction between the elements of the grinding wheel assembly  10  and the stabilizer assembly  50 . 
     In one embodiment of the invention, the contact surface of each hub roller  145   a ,  145   b  is brass. In other embodiments, the contact surface may be other metals such as steel, aluminum, copper, etc. In yet other embodiments, the contact surface may be nonmetallic materials such as rubber, plastic, glass, ceramic, or polymer composite. 
     In one embodiment of the invention, each hub roller  145   a ,  145   b  will have roller or ball bearings. In other embodiments, each hub roller  145   a ,  145   b  will have simple friction type bearings. In yet other embodiments, each hub roller  145   a ,  145   b  will be a high performance roller bushing. 
     FIG. 4 depicts an embodiment having two hub rollers  145   a ,  145   b . However, other embodiments will utilize one hub roller or three or more hub rollers to resist the torsional moment about axis A without generating significant part wear or friction. 
     In other embodiments of the invention, the torsional moment is resisted by means other than rollers. For example, in one embodiment, the hub rollers  145   a ,  145   b  are replaced with an air bearing system where air is injected into a collar that is part of the stabilizer assembly  50  and surrounds at least a portion of the cylindrical outer surface  55  of the hub  35 . The injected air is a bearing system, which resists the torsional moment about axis A while allowing the cylindrical outer surface  55  of the hub  35  to rotate within the collar without slidingly contacting the collar. 
     In FIG. 4, the slot cover  100  has been removed to reveal the curved slot  96  and a first set of cam followers  155   a ,  155   b . The first set of cam followers  155   a ,  155   b  are mounted on the cam follower carrier  90  and travel through the curved slot  96  as the cam follower carrier  90 , guide finger support  70 , index finger  75 , index finger travel adjustor  85 , linear adjustment lock lever  105 , and radial adjustment lock lever  110  displace relative to the slotted base  95 . When the cam followers  155   a ,  155   b , cam follower carrier  90 , guide finger support  70 , index finger  75 , index finger travel adjustor  85 , linear adjustment lock lever  105 , and radial adjustment lock lever  110  displace as a single unit relative to the slotted base  95 , the single unit is said to form a carrier-finger assembly  160 . The carrier-finger assembly  160  may be displaced as a whole relative to the slotted base  90  when the linear adjustment lock lever  105  is in a locked position and the radial adjustment lock lever  110  is in an unlocked position. It should be noted that while the drawings depict a slot  96  in the slotted base  95  that is curved, in other embodiments of the device  5 , the slot  96  may be linear or have other shapes. Also, in other embodiments, the orientation of the slot  96  may be horizontal, vertical, or inclined as needed to provide the desired adjustability relative to the blades  150 . 
     FIG. 4 illustrates three positions for the indexing finger  75  and the relationship between the blades  150  of the cutting reel  149  and the grinding wheel  30 , the index finger tip  80 , and the guide finger  65 . The three positions for the index finger  75  illustrated in FIG. 4 are the forward position, which is illustrated in dashed phantom lines and designated by the letter “F,” the rearward position, which is illustrated in dotted phantom lines and designated by the letter “R,” and the maximum rearward position illustrated in solid lines and designated by the letter “M.” 
     In operation, the index finger  75  pivots on a pivot pin  170  (shown in FIG. 5) between the forward position F and the rearward position R. Prior to operation, the index finger travel adjustor  85  is used to set the rearward position R so the index finger tip  80  aligns with the guide finger  65  such that when the index finger  75  is in the rearward position R, the index finger tip  80  is positioned very slightly rearward of the tip of the guide finger  65 . This allows the blade  150  to slide smoothly from the index finger tip  80 , along the tapered edge of the guide finger  65 , to the tip of the guide finger  65 . The maximum rearward position M is shown in FIG. 4 only to give an idea of the range over which the rearward position R may be set from the forward position F. 
     FIG. 5 is a front elevation view of the device  5  wherein the first and second vertical plates  120 ,  135  of the stabilizer assembly  50  have been made invisible to reveal aspects of the device  5  that are hidden in the preceding four figures. As shown in FIG. 5, the flange  60  is located between the flange rollers  130   a ,  130   b . The flange rollers  130   a ,  130   b  roll along the vertical surfaces of the flange  60  as the flange  60  rotates with the hub  35  about axis A. The flange rollers  130   a ,  130   b  are mounted by bolts  175   a ,  175   b  in the holes  125   a ,  125   b  of the first vertical plate  120 . The axis of each flange roller  130   a ,  130   b  is generally perpendicular to axis A. Thus, in one embodiment of the invention, the flange rollers  130   a ,  130   b  allow the stabilizer assembly  50  to maintain the indexing assembly  45  (i.e., the guide finger  65 ) in position relative to the grinding wheel  30  and axis A by resisting a bending moment along axis A; the flange rollers  130   a ,  130   b  prevent axial displacement of the indexing assembly  45  (i.e., the guide finger  65 ) relative to the grinding wheel  30  and axis A. In other words, by providing non-sliding bearing contact points between the stabilizer assembly  50  and the grinding wheel assembly  10 , the stabilizer assembly  50  helps to maintain the indexing assembly  45  in position relative to the grinding wheel  30  while generating minimal part wear and friction between the elements of the grinding wheel assembly  10  and the stabilizer assembly  50 . 
     In one embodiment of the invention, the contact surface of each flange roller  130   a ,  130   b  is brass. In other embodiments, the contact surface may be other metals such as steel, aluminum, copper, etc. In yet other embodiments, the contact surface may be nonmetallic materials such as rubber, plastic, glass, ceramic, or polymer composite. 
     In one embodiment of the invention, each flange roller  130   a ,  130   b  will have roller or ball bearings. In other embodiments, each flange roller  130   a ,  130   b  will have simple friction type bearings. In yet other embodiments, each flange roller  130   a ,  130   b  will be a high performance roller bushing. 
     FIG. 5 depicts an embodiment having two flange rollers  130   a ,  130   b . However, other embodiments will utilize one flange roller or three or more flange rollers to resist the bending moment along axis A without generating significant part wear or friction. 
     In other embodiments of the invention, the bending moment is resisted by means other than rollers. For example, in one embodiment, the flange rollers  130   a ,  130   b  are replaced with an air bearing system where air is injected into a collar that is part of the stabilizer assembly  50  and encompasses the annular stabilizer flange  60 . The injected air is a bearing system, which resists the bending moment along axis A while allowing the annular stabilizer flange  60  to rotate within the collar without contacting the collar. 
     In some embodiments of the invention, a rolling bearing means may be used to resist both the torsional and bending moments. For example, FIG. 10 shows a plan view of an alternative embodiment having a rolling bearing means for resisting both the torsional and bending moments. As illustrated in FIG. 10, a V-type roller  400  could be secured to the stabilizer assembly  50  so the roller&#39;s axis is generally parallel to axis A. The roller  400  could roll within a V-shaped or U-shaped bearing groove  405  cut into, and encircling, the cylindrical outer surface  55  of the hub  35 . In a similar embodiment, a similarly arranged roller  400  could roll in a bearing groove  405  formed on the cylindrical outer surface  55  of the hub  35  between two annular stabilizer flanges  60  radially emanating from the hub  35 . For greater stability, more than one V-type roller  400  could be radially positioned to ride in the bearing groove  405 . 
     FIG. 11 is another plan view of an alternative embodiment having a rolling bearing means for resisting both the torsional and bending moments. As illustrated in FIG. 11, a continuous set of ball bearings  410  is held in a ring  411  about the cylindrical outer surface  55  of the hub  35 . A bearing receiving plate  415 , which is connected to the second vertical plate  135  and secured to the traveling block  40  by two bolts  420   a ,  420   b , is located generally parallel and adjacent to the cylindrical outer surface  55  of the hub  35 . 
     In one embodiment, the receiving plate  415  radially encompasses at least a portion of the cylindrical outer surface  55  of the hub  35 . In other words, the receiving plate  415  forms a collar about at least a part of the cylindrical outer surface  55  of the hub  35 . The receiving plate  415  has a groove  425  that corresponds in size and orientation to the ball bearings  410  so as to mate with the ball bearings  410  as they travel along the receiving plate  415 . The groove  425  transfers the torsional and bending moments to the ball bearings  410 , which in turn transfers the moments to the shaft  15  via the hub  35 . Thus, the groove  425  and bearings  410  interposed between the hub  35  and the stabilizer assembly  50  interact to prevent the guide finger  65  from being axially or radially deflected relative to axis A. 
     In another embodiment similar to the one shown in FIG. 11, the ring  411  of ball bearings  410  is supported on the receiving plate  415  and the groove  425  is located on the cylindrical outer surface  55  of the hub  35 . Therefore, the ball bearings  410  transfer the torsional and bending moments to the groove  425 , which in turn transfers the moments to the shaft  15  via the hub  35 . Again, the bearings  410  and the groove  425  interposed between the hub  35  and the stabilizer assembly  50  interact to prevent the guide finger  65  from being axially or radially deflected relative to axis A. 
     FIG. 6 is a plan view of the device  5  with a blade  150  abutting the guide finger  65 , index finger tip  80 , and grinding wheel  30 . FIG. 6 reveals the threaded collar  54  has a spanner wrench hole  176 . FIG. 6 also reveals that the slotted base  95  has four holes  177   a ,  177   b ,  177   c ,  177   d  for receiving bolts, which secure the slotted base to the traveling block  40 . 
     As illustrated in FIG. 6, the index finger travel adjustor  85  comprises a pivot knob  180 , an interior shaft  185 , a securing knob  190 , a casing  195 , and a disk  200  (shown in FIG. 7) that has a stop pin  205 . The interior shaft  185 , the disk  200 , and the stop pin  205  form a singular unitary piece. In another embodiment, the interior shaft  185 , disk  200 , and stop pin  205  may be separate pieces. The pivot knob  180  is mounted on the end of the interior shaft  185  opposite from the disk  200 . The interior shaft  185  runs through the securing knob  190 , the casing  195 , and an adjustor hole  210  (shown in FIG. 7) near the top of the guide finger support  70 . 
     The index finger travel adjustor  85  may be used to adjust the amount of clearance between the stop pin  205  and the back of the index finger  75 , thereby allowing the rearward position R of the index finger  75  to be set at different positions relative to the forward position F. Decreasing the clearance between the stop pin  205  and the back of the index finger  75  decreases the distance that the index finger  75  may travel away from the forward position F to the rearward position R. In other words, the smaller the clearance between the stop pin  205  and the back of the index finger  75 , the less position R is offset back from position F (see FIG.  4 ). 
     To adjust the amount of travel the index finger  75  may undergo from the forward position F to the rearward position R, the securing knob  190  is loosened and the pivot knob  180  is turned to rotate the disk  200 , which brings the stop pin  205  closer to, or further away from, the back of the index finger  75 . Prior to operation, the stop pin  205  is positioned so the index finger tip  80 , when the index finger  75  is in the rearward R position, aligns with the guide finger  65  such that the index finger tip  80  is positioned very slightly rearward of the tip of the guide finger  65 . This allows a blade  150  to transfer smoothly from the index finger tip  80 , along the tapered edge of the guide finger  65 , to the tip of the guide finger  65 . Once the stop pin  205  is in the appropriate position, the securing knob  190  may be tightened to fix the stop pin  205  in place. 
     As shown in FIG. 6, the guide finger support  70  has a groove  215  in which a back plate  220  is located. The guide finger support  70  also has a spring base  225  connected to its side. 
     To describe aspects of the device  5  that are hidden in the preceding figures and better illustrate the interrelationship of the various aspects of the device  5 , reference is now made to FIG.  7 . FIG. 7 is an exploded isometric view of the device  5 . As shown in FIG. 7, a second set of cam followers  230   a ,  230   b  is mounted on the opposite side of the cam follower carrier  90  from the first set of cam followers  155   a ,  155   b . The cam followers  230   a ,  230   b  are located within a linear slot  235  located in, and aligned with, the groove  215  of the guide finger support  70 . 
     As indicated in FIG. 7, the linear adjustment lock lever  105  has an interior shaft  236  and a casing  240 . The interior shaft  236  connects to the linear adjustment lock lever  105  on one end and the back plate  220  on the other. The interior shaft  236  runs from the linear adjustment lock lever  105  to the back plate  220  by passing through the casing  240 , a hole  245  in the cam follower carrier  90 , and the linear slot  235  of the guide finger support  70 . The casing  240  nests within the curved slot  96  of the slotted base  95 . 
     When the linear adjustment lock lever  105  is in an unlocked position and the radial adjustment lock lever  110  is in a locked position, the linear slot  235  may displace along the second set of cam followers  230   a ,  230   b  and the casing  240 , and the groove  215  may displace along the back plate  220 . At this time, the guide finger support  70 , index finger  75 , and index finger travel adjustor  85  may displace relative to the cam followers  230   a ,  230   b , case  240 , linear adjustment lock lever  110 , radial adjustment lock lever  105 , cam follower carrier  90 , slotted base  95 , and back plate  220 . When the guide finger support  70 , index finger  75 , and index finger travel adjustor  85  displace as a single unit relative to the cam followers  230   a ,  230   b , case  240 , linear adjustment lock lever  110 , radial adjustment lock lever  105 , cam follower carrier  90 , slotted base  95 , and back plate  220 , the single unit is said to form a finger assembly  250 . It should be noted that while the drawings depict a slot  235  in the guide finger support  70  that is linear, in other embodiments of the device  5 , the slot  235  may be curved or have other shapes. Also, in other embodiments of the device  5 , the slot  235  may have a horizontal, vertical or inclined orientation. 
     The configurations of the carrier-finger assembly  160  and the finger assembly  250 , along with their respective adjustors, the radial adjustment lock lever  110  and the linear adjustment lock lever  105 , are advantageous. This is because the configurations allow the guide finger  65  to be positioned relative to the blade  150  and the grinding wheel  30  in a wide variety of manners. This is especially remarkable considering: (1) the compact nature of the carrier-finger assembly  160  and the finger assembly  250 ; and (2) the wide degree of positioning that may be achieved by manipulating no more than two adjustors, which are the linear adjustment lock lever  105  and the radial adjustment lock lever  110 . 
     As shown in FIG. 7, the radial adjustment lock lever  110  has an interior shaft  255  and a casing  260 . The interior shaft  255  runs from the radial adjustment lock lever  110  through the casing  260  and curved slot  96  to a connection with the cam follower carrier  90 . 
     As illustrated in FIG. 7, the pivot pin  170  of the index finger  75  resides in a pivot pin hole  265  in the lower portion of the guide finger support  70 . Below the pivot pin hole  265 , a limit pin  270  protrudes from the guide finger support  70  into a limit hole  275  in the lower part of the index finger  75 . The limit hole  275  is oversized so there is sufficient clearance between the limit pin  270  and the sides of the limit hole  275 . This clearance is such that it allows the index finger  75  to pivot between the forward position F and the maximum rearward position M without exceeding a maximum preset distance between these positions (see FIG.  4 ). 
     As shown in FIG. 7, the spring base  225  is connected to the side of the guide finger support  70 . A spring  276  is located between the spring base  225  and the back of the index finger  75 . The spring  276  causes the index finger  75  to bias into the forward position F. One end of the spring  276  nests in a spring hole  277  in the spring base, and the other end of the spring  276  nests in a hole in the back of the index finger  75 . 
     The operation of the device  5  during a relief grinding process will now be narrated while referring to FIGS. 1,  3 ,  4 ,  6  and  7 . The cutting reel  149  is located above the device  5 . The device  5  is positioned at a starting point wherein the device  5  straddles one end of the cutting reel  149  so that the grinding wheel  30  and guide finger  65  are located outside of the end of the blades  150  (i.e., the grinding wheel  30  and the guide finger  65  are located outside the envelope of the cutting reel  149 ) while the index finger tip  80  is located inside the end of the blades  150  (i.e., the index finger tip  80  is located inside the envelope of the cutting reel  149 ). 
     A motor biases the cutting reel  149  so the blades  150  rotate clockwise as designated by rotational arrow CW when viewed as shown in FIG.  3 . The biasing of the cutting reel  149  forces a blade  150  against the index finger tip  80 , which is maintained in the forward position F by the spring  276  compressed between the index finger  75  and the spring base  225 . The biased blade  150  forces the index finger  75  back against the spring  276  until the rearward travel of the index finger  75  is arrested by the stop pin  205 . The index finger  75  is now in the rearward position R, which is the position illustrated in FIGS. 4 and 6. As previously explained, the rearward position R has been set via the index finger travel adjustor  85  so the index finger tip  80  aligns with the guide finger  65  such that the index finger tip  80  is positioned very slightly rearward of tip of the guide finger  65 . This allows the blade  150  to slide smoothly from the index finger tip  80 , along the tapered edge of the guide finger  65 , to the tip of the guide finger  65 . 
     The device  5  is displaced along its rails  20   a ,  20   b  towards the opposite end of the blades  150 . Specifically, a displacement force is applied to the traveling block  40  that causes the traveling block  40  and its stabilizer assembly  50  to travel along the rails  20   a ,  20   b  as the rotating shaft  15  causes the hub  35  to rotate about axis A in a counterclockwise manner as indicated in FIG. 3 by rotational arrow CCW. As the stabilizer assembly  50  displaces, the flange rollers  130   a ,  130   b , which are in rolling bearing contact with the rotating flange  60 , cause the rotating hub  35  to displace along the rotating shaft  15 . 
     In one embodiment of the invention, the displacement force is applied to the traveling block  40  via a chain or cable. In another embodiment, the force is applied via a threaded shaft or pinion and gear rack. In yet other embodiments, the force is applied via a hydraulic or pneumatic ram or system of mechanical levers or any other means of applying a displacing force to the traveling block  40 . 
     As the device displaces, the blade  150  transfers from the index finger tip  80  to the guide finger  65  and the spinning grinding wheel  30  makes contact with the blade  150 . As the grinding wheel  30  is displaced along the blade  150 , the blade  150  undergoes a relief grinding process as it follows the guide finger  65 . 
     The device  5  travels the length of the blade  150  to the end of the blade  150  opposite the starting point, which is called, for the purposes of this specification, the end point. The device  5  stops traveling once it reaches the end point, which is where the index finger tip  80  has passed the end of the blade  150  being relief ground (i.e., the index finger  80  has passed the end of the envelope of the cutting reel  149 ) while the blade  150  being relief ground still remains biased against the guide finger  65  (i.e., the guide finger  65  is still within the envelope of the cutting reel  149 ). 
     At this point, the index finger tip  80  is no longer held in the rearward position R by the blade  150  being relief ground. As a result, the index finger  75  biases forward into the forward position F. Once the index finger  75  is in the forward position F, the device  5  begins traveling back to the starting point. As the device  5  returns to the starting point, the guide finger  65  travels along the front of the blade  150  being relief ground while the index finger point  80  travels along the back of the blade  150 . 
     Once the device  5  reaches the starting point, the guide finger  65  slides past the end of the blade  150  being relief ground and the cutting reel rotates, bringing a new blade  150  forward to the index finger tip  80  in the forward position F. The new blade catches on the index finger tip  80  and forces the index finger  75  back into the rearward position R. The new blade  150  transfers from the index finger point  80  to the guide finger  65  as the device  5  begins to return to the end point. The process continues to cycle in the aforementioned manner until all of the blades  150  on the cutting reel  149  have been relief ground. 
     As explained above, the blade  150  being relief ground is biased against the indexing assembly  45  (i.e., the guide finger) while the grinding wheel  30  travels along the blade  150 . Therefore, the biased blade  150  exerts a force on the guide finger  65 . The force causes a torsional moment about axis A that is resisted by the rails  20   a ,  20   b  and by hub rollers  145   a ,  145   b , which are in rolling contact with the rotating cylindrical outer surface  55  of the hub  35 . The force also causes a bending moment along axis A that is resisted by the rails  20   a ,  20   b  and by the flange rollers  130   a ,  130   b , which are in rolling contact with the rotating annular flange  60  of the hub  35 . 
     The resistance to the torsional moment provided by the hub rollers  145   a ,  145   b  prevents the guide finger  65  from radially deflecting (i.e., deflecting front to back). The resistance to the bending moment provided by the flange rollers  130   a ,  130   b  prevents the guide finger  65  from axially deflecting (i.e., deflecting side to side). Thus, the flange and hub rollers  130   a ,  130   b ,  145   a ,  145   b  allow the device  5  to maintain tight tolerances between the position of the outer radial surface of the grinding wheel  30  and the guide finger  65  during a relief grinding process. In other words, the flange and hub rollers  130   a ,  130   b ,  145   a ,  145   b  allow the guide finger  65  to remain fixed relative to axis A. The resistance to the moments provided by the flange and hub rollers  130   a ,  130   b ,  145   a ,  145   b  also allows the use of rails  20   a ,  20   b  that are of a diameter that is commonly utilized in relief grinding systems that employ a common rotating shaft  15 . 
     In another embodiment, the hub rollers  145   a ,  145   b  and or flange rollers  130   a ,  130   b  are eliminated and the moment(s) is/are resisted by rails  20   a ,  20   b , which have been increased in diameter to increase their stiffness. To achieve the necessary stiffness, steel circular rails should have a diameter of at least approximately 3.5 inches. Rails made of other materials will have greater or lesser minimum diameters depending on the modulus of elasticity of the materials utilized. Increasing the rail diameter requires a corresponding increase in the size of the traveling block  40 . 
     In another embodiment, as illustrated in FIGS. 8 a  and  8   b , the hub rollers  145   a ,  145   b  and/or flange rollers  130   a ,  130   b  are eliminated and the moment(s) is/are resisted by profiled rails  280   a ,  280   b , which have diameters that are commonly utilized in relief grinding systems that employ a common rotating shaft  15 . As shown in FIG. 8 b , the profiled rails  280   a ,  280   b  are stiffened by connection points  282  between the profiled rails  280   a ,  280   b  and the surrounding framework  146  of the overall grinding system  147 . As shown in FIG. 8 a , the profiled rails  280   a ,  280   b  pass through similarly profiled holes  285   a ,  285   b  in the traveling block  40 . 
     In another embodiment, as shown in FIGS. 9 a  and  9   b , the profiled rails  290   a ,  290   b  are stiffened by connection points  282  between the profiled rails  290   a ,  290   b  and the surrounding framework  146  of the overall grinding system  147 . FIG. 9 b  is a sectional elevation of the right profiled rail  290   a  taken along section line AA of FIG. 9 a . As indicated in FIG. 9 b , the profiled rails  290   a ,  290   b  pass through holes  295   a ,  295   b  in the traveling block  40 . The holes  295   a ,  295   b  have rollers  300  that roll along the faces of the profiled rails  290   a ,  290   b . 
     Some embodiments of the invention, to resist the moments, will utilize both a system of rolling bearing elements in the stabilizer assembly  45  and a profiled rail system. Other embodiments will rely mainly on a system of rolling bearing elements in the stabilizer assembly  45  to resist the moments. Finally, other embodiments will rely solely on a profiled rail system to resist the moments. 
     In the embodiments utilizing profiled rails, the profiled rails allow the guide assembly  25  to maintain the indexing assembly  45  in position relative to the grinding wheel  30  by resisting a torsional moment about axis A and/or a bending moment along axis A. In other words, the guide assembly  25  does not need to rely on contact between the grinding wheel assembly  10  and the bearing system elements of the guide assembly  25  in order to resist the moment(s) while maintaining the indexing assembly  45  in position relative to the grinding wheel  30  and axis A. 
     In the embodiments where all of the moments are resisted by profiled rails and the moment resisting rollers  130   a ,  130   b ,  145   a ,  145   b  are eliminated, the grinding wheel  10  assembly may be moved axially along the rotating shaft  15  via light duty rollers or sliding type forks. The light duty rollers or sliding type forks would be mounted on the guide assembly  25  and would act on a flange  60 , a groove in the cylindrical outer surface  55  of the hub  35 , or other similar features of the hub  35 . The light duty rollers or sliding type forks would experience minimal part friction and wear because they would not need to resist the moments. 
     Although the present invention has been described with reference to preferred embodiments, persons skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.