Abstract:
A movable frame assembly to move a device for dressing a grinding wheel for the sharpening an ice skate blade. The device uses a housing surrounding a grinding wheel and movable frame with a swing arm. A dressing tool is mounted in the dresser swing arm and the dresser swing arm is rotatable between a storage position and an operating position. The movable frame assembly slides along rails to allow positioning of the dressing tool into the grinding wheel. Horizontally and vertically disposed bearings are positioned beside and under a rail with resiliently biased bearings are held against the top of the rail. The bearings help the rails of the movable frame move smoothly. The rails are spaced apart by yokes on the arm or a bar across the top of the dresser to prevent binding as the movable frame is slid for dressing the wheel. Adjustment of the rails is also provided for by adjustment slots at the back of the rails.

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
       [0001]    This application is a Continuation-In-Part application based on Ser. No. 08/991,473 filed Dec. 16, 1997. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    The field of the invention pertains to grinding wheels. In particular, the invention pertains to a device for dressing or shaping the grinding wheel for sharpening and imparting a certain shape to the blade of an ice skate. In the past, dressing the wheel was inexact and hence the shape given to an ice skate blade was variable. The dressing devices were not stabilized enough to keep the dressing tool in a consistent relation with the grinding wheel. Another disadvantage was that the placement of the dressing tool to the grinding wheel was difficult as the dressing tool was not easily movable.  
           [0003]    By dressing the grinding wheel, a certain shape is imparted to the wheel, which shape then is imparted to the ice skate blade as the blade is sharpened by the wheel. Skates for certain purposes require certain shapes. A hockey player needs a hollow or a radius to be ground on the blade of the ice skate. The hollow grind creates two edges on the outside of the blade by lowering the center portion beneath the edges. A goalie on the other hand needs an almost flat blade with minimum of hollow provided to the skate. As skates are ground, the grinding wheel loses its shape, necessitating dressing of the wheel. Or when a different shape is needed, the grinding wheel must be dressed to the desired shape for the wheel to be able to impart the desired shape to the ice skate blade.  
           [0004]    It is important the deepest part of the hollow be centered on the ice skate blade. If the deepest part of the hollow is too far to one side of the blade, the skater will be forced off balance thus affecting the skater&#39;s performance.  
         SUMMARY OF THE INVENTION  
         [0005]    A grinding wheel is partially contained within a housing that has a top cover or plate, a bottom, a back and sides. The invention includes a slide mechanism or rail assembly to move a dresser arm with dresser tool into and away from a grinding wheel. The grinding wheel is rotated horizontally for grinding, in this case, an ice skate blade. The dresser arm is moved in a horizontal direction along a rail assembly having a rail on each side of the housing.  
           [0006]    The dresser arm is attached to ends of two rails and the dresser arm pivots around the attachment point of the rails. The dresser arm is slid via movable frame assembly/rails to place the dresser arm/dresser tool near the circumferential edge of the grinding wheel for the dressing operation.  
           [0007]    The dresser arm with tool is moved in an arc for the dressing of the grinding wheel. The dresser arm is moved into engagement with the grinding wheel by pulling or pushing the dresser to move along the rails of the movable frame assembly. The movable frame assembly uses a rail on either side of the housing and a cross bar at the back of the housing. As discussed above, the dresser arm connects between the ends of the rails.  
           [0008]    The movable frame assembly is positioned along the sides of a housing that partially encases the grinding wheel; leaving a portion of the wheel exposed. The exposed portion of the wheel is the location at which grinding occurs and the exposed portion of the wheel is also the location where dressing of the wheel occurs.  
           [0009]    The movable frame assembly generally has two rails, one on each side of the housing. The rails are connected at the front by the dresser arm and at the back by a crossbar.  
           [0010]    Bearings support the rails and the bearings being of a lubricating material, lubricate the movement of the rails. Both fixed and resilient bearings are used herein. Fixed bearings are disposed in a horizontal orientation and a vertical orientation. Fixed horizontal bearings are under each of the rails. The horizontal bearings are positioned perpendicularly to the sides and also to the rails. The bottom of the housing that holds the horizontal bearings extends to the outside of the side wall with the bearings placed therein with the horizontal bearings extending into the housing past the side wall of the housing.  
           [0011]    Vertical bearings are placed and retained within partially circular cutouts in the side walls. The vertical bearings extend higher and lower than the rails and space the rails from the side walls, preventing binding of the rails with the side walls of the housing.  
           [0012]    Resilient bearings or detents are used to hold the rails in position on the fixed horizontal bearing under the rails. The resilient bearings press against the rails from the top of the rails. The resilient bearings are held in a block above the rail with the block being attachable to the side wall of the housing. Alternately, the resilient bearings are held by the top plate of the housing with the top plate being extended beyond the side walls and over the rails of the rail assembly.  
           [0013]    The rails can be shafts or bars. A bar having a square cross section can be used. A concavity can be formed into the rail to allow any grinding dust or other foreign materials to drop away from the rail. The resilient detents can be added to the rail itself to work against a top surface to force the rail against the fixed horizontal bearing under the rail.  
           [0014]    It is to a device for moving the dressing arm for the dressing of a grinding wheel for the sharpening of an ice skate blade to which the present invention is directed. The device locates and stabilizes the dressing tool for the dressing of the wheel and hence results in the sharpening of the ice skate blade with the desired shape. The device easily is moved into working position without binding.  
           [0015]    Essentially, the invention comprises a housing almost completely surrounding the grinding wheel. The housing has a planar plate with sides and a back rising from the plate. A top plate fits to the housing almost encasing the grinding wheel. A segment of the wheel remains exposed for the actual dressing or sharpening. The housing protects the grinding wheel itself and also provides mass to dampen the vibration during the dressing of the wheel and during the sharpening process. The housing also provides some protection to the operator by containing the pieces of the grinding wheel in case the grinding wheel should break apart.  
           [0016]    The grinding wheel is mounted on an end of a drive shaft that terminates inside the housing at the grinding wheel. The drive shaft is powered conventionally by a drive motor. A sliding mechanism is movable along the sides of the housing. At the front of the sliding mechanism, the dresser arm is designed to swing into place to position the dressing tool to the grinding wheel.  
           [0017]    After the dresser arm swings the dressing tool in front of the grinding wheel, the dressing tool is introduced to the grinding wheel by moving the sliding mechanism so that the grinding tool engages with the grinding wheel. The dresser arm has an adjustment to allow the dresser tool to be placed against the desired point on the edge of the wheel. The adjustment is by an eccentric adjustment wheel at both ends of the dresser arm.  
           [0018]    The movable frame comprises rails and/or shafts that slide on bosses on the sides of the housing. Bearings on the bosses and the housing facilitate the movement of the shafts. The rails/shafts connected at the front by the dresser arm and at the back by a cross bar. Blocks are affixed to the housing above the shafts to hold the shafts. Fixed and/or resilient bearings are added to the rails/shafts and to the blocks to allow the movable frame to easily slide into position. The bearings in the rails/shaft can be strip bearings that are placed into longitudinal grooves milled in the shafts. Resilient bearings or detents are also useful to provide resilient holding.  
           [0019]    The rails/shafts must be maintained parallel with each other. Holding the rails/shafts apart or spacing the rails/shafts prevents binding of the movable frame. This is accomplished by attaching the ends of the rails/shafts within the yokes or split ends of the dresser arm. The mass of the dresser arm prevents the shafts from narrowing together and binding. The cross bar also is used for adjustably spacing the rails/shafts.  
           [0020]    An alternate rails/shaft spreading device is a spacer connected above the housing. The spacer device comprises two bars that each have a vertical part that is joined to the rails/shaft. Each bar angles to a horizontal part over the top of the housing. The ends of the horizontal parts are threaded, one with right hand threads and the other with left hand threads. A connector having reverse threads, that is, one end having left hand thread and the other end having right hand threads, (similar to a turn buckle) is joined to the bars. Adjustment is made by turning the connector to space the rails/shafts apart or closer together. Lock screws secure the bars at the optimum spacing.  
           [0021]    It is envisioned that the device can be advantageously employed with a variety of grinding devices, not just for skate grinding devices. An advantage of this device is the dresser tool is easily slid into position. This invention can be used on other types of grinder/sharpeners.  
           [0022]    For a more complete understanding of the present invention, reference is made to the following detailed description when read with in conjunction with the accompanying drawings wherein like reference characters refer to like elements throughout the several views, in which: 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0023]    [0023]FIG. 1A illustrates a perspective view of the dresser device according to the invention;  
         [0024]    [0024]FIG. 1B illustrates a close-up partial front view of the side of the dresser device with the block over the rail and bearings vertical and horizontally disposed to the rail according to the invention;  
         [0025]    [0025]FIG. 1C illustrates a close-up partial front view of a variation of the dresser device with the top plate holding the block over the rail and resiliently biased bearings riding on the top of the rail according to the invention;  
         [0026]    [0026]FIG. 2 illustrates a partial side view of the rail showing the adjustment wheel;  
         [0027]    [0027]FIG. 3 illustrates a view of an end of the dresser arm showing the yoke;  
         [0028]    [0028]FIG. 4 illustrates a front view of a spacer device for mounting to the rails and connecting the rails above the housing;  
         [0029]    [0029]FIG. 5 illustrates a back view showing the means for adjusting on the back of a rail;  
         [0030]    [0030]FIG. 6 illustrates a view of the side block;  
         [0031]    [0031]FIG. 7 illustrates a view showing a rail of the rail assembly having resilient bearings in the rail;  
         [0032]    [0032]FIG. 8A illustrates a top view showing the means for adjusting on the front end of a rail;  
         [0033]    [0033]FIG. 8B illustrates a front view showing the means for adjusting on the front of a rail; and  
         [0034]    [0034]FIG. 9 illustrates a top view showing the means for adjusting with the back of the device with the side of the housing shown in section.  
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0035]    In FIG. 1A, a dressing device for shaping a grinding wheel to sharpen ice skate blades generally denoted as  10  is thereshown. The dressing device  10  comprises a housing  12 , a movable frame assembly  14 , and a dresser arm  16  with a dressing tool(not shown but indicated by center line  18 ) attached thereto. The dresser arm  16  swings between a storage position  20  and a dressing position  22 . In the storage position  20 , the dresser arm  16  is retained by a locking mechanism  24  on rod  23 . After the dresser arm  16  is swung into the dressing position  22 , the dresser arm  16  with the dressing tool  18  is then movable on a horizontal plane via the movable frame assembly  14  into and away from a grinding wheel  25  for a dressing operation.  
         [0036]    The housing  12  of the dressing device  10  comprises a planar bottom plate  26 , with a back  28  and sides  30 ,  30  extending perpendicularly therefrom. A top plate or cover  32  with depending front edges  34 ,  34  fits to the housing  12 . The housing has an opening  35  to allow a portion of the grinding wheel  25  near the circumference of the grinding wheel  25  to extend beyond the housing  12 . However, most of the grinding wheel  25  is covered by the housing  12 .  
         [0037]    The grinding wheel  25  is driven by a drive shaft  36  powered by motor (not shown) contained within a motor housing  37 . Thus the grinding wheel  25  is rotated to provide the necessary sharpening to an ice skate blade. The drive shaft  36  is enclosed within a pedestal  38 , upon which the housing  12  is placed.  
         [0038]    Movable frame assembly  14  comprises rails  40 ,  40  on either side of the housing  12  to which the dresser arm  16  is connected. Rails  40 ,  40  are also connected at the back of the housing  12  by a cross bar  42 .  
         [0039]    Rails  40 ,  40  slide along bosses  44 ,  44  extending from the housing  12 . Rails  40 ,  40  can be shafts, bars or have other configurations. Bearings  46 ,  46  can be emplaced to the bosses  44 ,  44  and to the housing  12  to facilitate the movement of rails  40 ,  40 . Above rails  40 ,  40 , blocks  48 ,  48  are affixed to opposite sides of the housing  12 . Bearings generally indicated as  47  can be added to the sides  30  of housing  12  to fit vertically between block  48  and the side  30 . (One side  30  and one rail  40  will be further described herein. However, the description is applicable to the other side  30  and the other rail  40 .)  
         [0040]    Two or more vertical bearings  47  extend lower than the rail  40  and space rail  40  out from side  30 , preventing binding. Block  48  is depicted as a single block but block  48  could be formed in several pieces. One or more horizontal bearings  46  fit under rail  40  while resilient bearings  51  ride on the top of the rail  40 . Resilient bearing  51  is generally vertically disposed.  
         [0041]    Resilient bearing  51  acts as a detent and can have a resilient coil disposed around the bearing to bias the bearing  49  against the rail  40 . Bearings  46 ,  47  and  51  are generally cylindrical. Bearings  47  are generally disposed vertically while bearings  46  are generally disposed horizontally. Bearings  47  are cylindrical and fit in partially circular cut outs  49  in the housing  12 . Bearings  47  extend beneath the block  48  and lower than adjacent shafts  40 ,  40 . Bearings  47  force rails  40 ,  40  out from the housing  12  and thus prevent binding of rails  40 ,  40  as the rails slide against the described bearings as the dresser arm  16  is moved forward and backward. Bearings  46 ,  47  and  51  can be formed from Teflon material or other material having lubricating properties such as Delrin.  
         [0042]    [0042]FIG. 1B is a close-up partial front view showing the circumference of rail  40  with bearing  47  partially recessed into a vertical partially circular cut out  49  in the side  30 . Block  48  is mounted to side  30  above rail  40 . Bearing  46  is shown horizontally disposed under the rail  40 . Bearing  46  is recessed into the boss  44 . Boss  44  can be formed as an integral part of bottom plate  26  with bearing  46  extending under side  30  for ease of removal.  
         [0043]    [0043]FIG. 1C shows a close-up partial front view of a variation whereby the top plate  32  extends over rail  40 . Resilient bearing or detent  51  are in block  48 . Resilient bearing  51  rides on rail  40 . Alternately, resilient bearings  51  or detents can be emplaced in the rail  40  itself to directly engage the top plate  32  (see FIG. 7). One or more resilient bearings  51  can be used advantageously in the block  48 .  
         [0044]    Now turning to FIG. 2 thereshown is an adjustment wheel  50  on the front end of the rail  40 . Adjustment wheel  50  is also provided on the rail on the opposite side of the housing. Adjustment wheel  50  is fitted into a milled pocket  52  in rail  40 . The dresser arm  16  is affixed to the adjustment wheel  50 . The adjustment wheel is an eccentric wheel and when turned moves the dresser arm  16  slightly above and below the center of the line through the ends of the shafts. Thusly, is fine adjustment of the dressing tool  18  accomplished. A strip bearing  55 , such as brass or Teflon, is shown inserted into a milled slot  53  in rail  40 .  
         [0045]    Spacing apart rails  40 ,  40  and maintaining the spacing and parallelism of the rails is important to the easy movement of the movable frame assembly  14 . Rails  40 ,  40  need to be spaced properly to limit binding of the movable frame assembly  14 . FIG. 3 shows the dresser arm  16  at the front of the device as having a split end or yoke  54  provided at the end into which rail  40  is attached. Another yoke  54  is provided on the other end of the dressing arm on the other rail (not shown). Adjustment is provided within the space of the yoke opening. Rails  40 ,  40  can come no closer together than the smallest dimension of the yoke  54  openings.  
         [0046]    An alternate spacing device  56  is depicted in FIG. 4. This spacer device is at the back of the movable frame assembly near the back of the housing  12 . Spacer device  56  attaches to rails  40 ,  40  through slots  58 ,  58  provided in rails  40 ,  40  or to a saddle or a clamp around the rails (not shown). The spacer device  56  comprises two arms  60 ,  60 . Arms  60 ,  60  each have a vertical part  62  that is angled into a horizontal part  64 . Threads  66 ,  66  are worked on the ends  68 ,  68  of the arms away from rails  40 ,  40 . One arm has right hand threads, while the other arm has left hand threads. A connector  70  spans the gap between the ends  68 ,  68  of the arms. Connector  70  has threads to match those of the ends of the arms. Connector  70  is turned to draw rails  40 ,  40  closer together or turned the other way to move rails  40 ,  40 ′ farther apart. The desired spacing is retained by tightening set screws  71  through the connector  70  to lock the spacing of rails  40 ,  40 .  
         [0047]    Now turning to FIG. 3, a back view of cross bar  42  is thereshown. Cross bar  42  has a longitudinal slot  72  and a notch  73  therethrough. Ends of rails  40 ,  40  engaging with the cross bar  42  have flats thereon the rails to engage with the slot  72  and the notch  73 . Adjustment and alignment of rails  40 ,  40  can be made here also.  
         [0048]    [0048]FIG. 6 depicts a block  48  for holding rail  40  along a side of the housing  12 . Each side of the device  12  can employ a block  48 , but one block will be described herein. Block  48  is fitted above rail  40  and is affixed to the housing  12 . Block  48  can have a semicircular cutout to fit around bearing  47 . Resilient bearings  51  can be mounted through block  48  to press down on the top of rail  40  beneath (not shown). Rail  40  easily slides between the block  48  and the boss  44 , which can be formed on the housing  12 . Bearings  46  can be made from lubricated material such as Teflon or Delrin.  
         [0049]    Better shown in FIGS. 1B and 1C, bearings  46 ,  46  can be mounted in boss  44  to support the under side of rail  40 . Resilient bearing  51  or plunger detent can be added to block  48  to ride on the top of rail  40  when block  48  is assembled to side  30 . Resilient bearing  51  can hold down a bearing insert  74  on the top of rail  40 . Resiliently biased bearing  51  positions a bearing insert  74  to ride on the shaft yet not bind the shaft.  
         [0050]    Bearings  47 ,  47  are also made from a lubricated material such as Teflon or Delrin. Bearings  47 ,  47  are fittable into semicircular cutout in the block  48  and a corresponding partially circular cutout  49  in the sides  30 ,  30 . The partially circular cutout  49  in the sides  30 ,  30  is larger than a semicircle and holds the bearing  47  in place.  
         [0051]    Bearings  46 ,  47  and  51  prevent the rail from binding against the housing. Bearings  46 ,  46  extend under rail  40  while bearings  47 ,  47  space between rail  40  and the side  30  of the housing, thus preventing binding of rail  40 .  
         [0052]    A set screw (not shown) having a nylon tip can be inserted on centerline  76  to tighten against the bearing  51  to maintain the position of the bearing.  
         [0053]    [0053]FIG. 7 shows rail  40  as having a generally square cross section. One face of rail  40  has a concavity  78  running the entire length of rail  40 . Chamfers  80 ,  80  connect from the concavity  78  to the top and the bottom of rail  40 . Resiliently biased bearings  51  or detents are positioned in the rail  40  itself for the resilient bearing to engage directly with the bottom side of the top plate  32  (not shown). Concavity  78  is positioned towards side  30 .  
         [0054]    [0054]FIG. 8A shows a top view of rail  40  with an adjustment slot  82  for adjusting the dresser arm, the adjustment slot  82  being at an end of rail  40  near to the point where the dressing arm  16  (not shown) is attached. FIG. 8B shows a front view of adjustment device  84  shown assembled to rail  40 . Adjustment device  84  has an elongated slot  86  for vertical adjustment of rail  40 .  
         [0055]    Now turning to FIG. 9, the movable frame assembly  14  is thereshown in a partial top view. Sides  30  and back  28  of the housing  12  are depicted in partial section with bearings  47  in partially circular cut outs  49  in side  30 . Rails  40  are connected behind the back  28  of housing  12  by cross bar  42 . Means for adjustment  43 , hereshown as a threaded handle through the cross bar  42  engages the back  28  of housing  12  and limits the travel of the movable rail assembly  14  in a forward direction.  
         [0056]    Having described my invention, many modifications thereto will become apparent to those skilled in the art to which it pertains without deviation from the spirit of the invention as defined in the appended claims.