Patent Publication Number: US-2022212308-A1

Title: Method and system for control of ice skate blade grinding apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This patent application is a continuation-in-part patent application that claims the benefit of U.S. patent application Ser. No. 16/988,610 filed Aug. 8, 2020, which is a continuation-in-part patent application that claims the benefit of U.S. utility patent application Ser. No. 16/854,433, filed Apr. 21 2020, which claims the benefit of U.S. provisional patent application No. 62/898,989, filed Sep. 11, 2019. All of the aforementioned applications are hereby incorporated by reference herein. 
    
    
     FIELD 
     The present application relates generally to apparatuses for sharpening and profiling multiple ice skate blades held together and, more particularly, to a method and system for control of such an apparatus based on the number of blades inserted therein. 
     BACKGROUND 
     Sharpening apparatuses for grinding or sharpening blades such as skate blades have been available for decades. However, the prior art sharpening apparatuses are often manual and require extensive skills and experience of the person doing the sharpening. This results in varying sharpening results and makes it more difficult for users of skate blades to obtain properly sharpened skate blades. There is a need for an effective sharpening method and apparatus that is easy to use while providing consistent and high-quality sharpening of skate blades, particularly when multiple blades are held together. 
     SUMMARY 
     In some embodiments, there is provided an ice skate blade grinding apparatus with an automatic blade holder that automatically senses the number of blades held in the blade holder and sets an operating parameter of an ice skate blade grinding apparatus based on the sensed number of blades. 
     In other embodiments, there is provided an automatic blade holder that automatically senses the number of blades held in the blade holder and horizontally shifts the blades upon completion to make sure the next time the blade holder is used, a non-worn portion of the grinding belt aligned on top of the next batch of blades to be sharpened. 
     Accordingly, there is provided an automatic blade holder that provides a solution to the above-outlined problems. More particularly, the blade holder has a movable plate and a fixture. A rotatable bolt is in operative engagement with a block attached to the plate. A motor is in operative engagement with the bolt. The motor rotates the bolt to move the plate towards (or away from) the fixture to grip a first set of blades until a torque threshold value is reached. The processor determines a number of blades included in the set of blades based on the number of rotations of the bolt when the torque threshold value is reached. A first grinding portion of a rotating abrasive belt is applied against the first set of blades, wherein the first set of blades has a total width W 1 , to sharpen the set of blades. A vise is slid sideways a distance W 1  until a second grinding portion is aligned on top of the second set of blades. 
     The method further comprises the step of the motor automatically reducing a gripping force for a second set of blades wherein the second set of blades includes fewer blades than the first set of blades. 
     The method further comprises the step of sliding a slide, attached to the vise, along a rail to shift the vise relative to the belt. 
     The method further comprises the step of providing a linear actuator that has a rod in rotational engagement with a bolt secured to a piece in operational engagement with the slide. 
     The method further comprises the step of simultaneously sharpening the blades contained in the first set of blades. 
     The method further comprises the step of rotating the rod to shift the vise relative to the belt. 
     The method further comprises the step of inserting a motor shaft into the bolt. 
     The method further comprises the step of providing the block with an opening defined therein to threadedly engage the bolt. 
     The method further comprises the step of determining a gripping gap between the plate and the fixture by counting a number of rotations of the shaft. 
     The method further comprises the step of providing the shaft with an elongate protrusion and inserting the protrusion into a groove at an end of the bolt. 
     In other embodiments, there is provided an ice skate blade grinding apparatus that implements a method whereby the apparatus determines a number of contiguous ice skate blades inserted into the apparatus, and sets and/or varies an operating parameter of the apparatus based at least in part on the determined number of contiguous ice skate blades. 
     In yet another embodiment, there is provided a non-transitory computer-readable medium comprising computer-readable instructions which, when read and executed by a processor of an ice skate grinding apparatus, cause the apparatus to carry out a method that includes determining a number of contiguous ice skate blades inserted into the apparatus; and setting an operating parameter of the apparatus based at least in part on the determined number of contiguous ice skate blades. 
     In a further embodiment, there is provided an ice skate grinding apparatus, comprising a holding mechanism configured to hold one or more ice skate blades under pressure; a grinding mechanism connected to the holding mechanism, the grinding mechanism configured to cause an abrasive element to move relative to, and contact under pressure, an ice-contacting surface of the blades; and a processing entity configured for controlling a set of operating parameters, the operating parameters including at least the pressure of the holding mechanism, the pressure of the grinding mechanism and relative movement of the abrasive element and the blades. The processing entity is further configured to determine the number of ice skate blades held together by the holding mechanism, and is also configured to set at least one of the operating parameters based at least on the determined number of contiguous ice skate blades held by the holding mechanism. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is an exploded side view of a portion of a blade holder in accordance with a non-limiting embodiment; 
         FIG. 2  is a detailed view of the end of the smooth section of the blade holder; 
         FIG. 3  is an elevational side view of a portion of the blade holder in an open position; 
         FIG. 4  is an elevation side of the portion of the blade holder holding a plurality of blades; 
         FIG. 5  is a perspective view of the blade holder showing a shifting mechanism; 
         FIG. 6  is substantially similar to the view of  FIG. 4  but shows the grinding belt shifted to the side to align a non-worn belt portion with the new set of blades to be sharpened; 
         FIG. 7  is a perspective view of the blade holder including an abrasive belt assembly; 
         FIG. 8  is a perspective view of the blade holder including the abrasive belt assembly shown in  FIG. 7 ; 
         FIG. 9  is an elevational side view of a belt grinding profiling apparatus, in accordance with another embodiment; 
         FIG. 10  is a detailed perspective front view of the belt grinding profiling apparatus shown in  FIG. 9 ; 
         FIG. 11  is an elevational side of a tiltable vise in an open position; 
         FIG. 12  is an elevational side view of a first embodiment of a template; 
         FIG. 13  is an elevational side view of a second embodiment of a template; 
         FIG. 14  is an elevational side view of a third embodiment of a template; 
         FIG. 15  is an elevational side view of a fourth embodiment of a template; 
         FIG. 16  is a perspective front side view of an ice skate blade grinding machine in accordance with a non-limiting embodiment; 
         FIG. 17  is an elevational side view of the machine of the present invention 
         FIG. 18  is a flowchart of a process that can be executed by a processor of the ice skate blade grinding apparatus; 
         FIG. 19  shows a computing environment for the processor of the ice skate blade grinding apparatus; and 
         FIG. 20  is a top or bottom view of a plurality of blades showing inter-blade transitions. 
     
    
    
     DETAILED DESCRIPTION 
     With reference to  FIG. 1 , the blade holder  100  has a sturdy vise  102  that acts as a frame for all other components and is designed to withstand all the forces that is applied thereon. The blade holder  100  is very compact. One feature of the blade holder is that it can automatically determine how many blades are to be sharpened and how hard the blades should be clamped or held together. In other words, the blade holder  100  automatically adjusts the gripping force or torque value depending on how many blades are to be simultaneously sharpened. It can also automatically shift the entire holding mechanism so that a new non-worn portion of the sharpening belt is aligned with the next batch of blades that are to be sharpened by the belt. 
     The vise  102  has a hollow space  116  defined therein to receive a rotatable threaded bolt  118 , as explained in detail below. The vise  102  has, at one end  104 , a round opening  106  defined therein and therethrough to receive a round inset  108 . The inset  108  has a round opening  110  defined therein to receive a rotatable motor shaft  112  extending from a gearbox  115  of an electric motor  114 . The inset  108  prevents horizontal movement of the bearing  168  and has an outside thread  109  that is screwed into the round opening  106 . The motor  114  has an encoder  117  that measures and monitors the number of rotations of the shaft  112 . An upper side  120  of the vise  102  has a groove  122  defined therein to receive a wedge  124 . A plate  126 , having bolts  128 , rests on the upper side  120  of vise  102 . The bolts  128  are screwed into threaded openings  130  defined in a shiftable or movable block  132  to hold the plate  126  to the block  132 . The block  130  has a round opening  134  defined therein to receive a threaded portion  136  of the bolt  118 . The plate  126  may be integral with the block  132 . 
     As explained below, by keeping track of the number of rotations of the shaft  112 , it is possible to determine how much the plate  126  has been shifted horizontally relative to the fixture  154  and how big the gripping gap  119  (best shown in  FIG. 3 ) is between an engagement surface  121  of the plate  126  and an opposite engagement surface  123  the fixture  154 . It is also possible to determine the size of the gap  119  by sensing the position of the plate  126  with a position sensor without measuring the number of rotations of the shaft  112 . 
     The bolt  118  has a flange  140  that has a diameter greater than a diameter of the threaded portion  136 . One function of the flange  140  is to prevent horizontal movement of the bolt  118  during operation of the blade holder  100 . The flange  140  separates the threaded portion  136  from a smooth section  142 . At an end  144  of the smooth section  142 , there is a threaded section  146  that has an opening  148  defined therein. The opening  148  has a cut-out  150  defined therein to receive an elongate protrusion  152  of the shaft  112  of the motor  114  to prevent the shaft  112  from rotating relative to the bolt  118  so that when the shaft  112  is rotated the bolt  118  also rotates. 
     The upper surface  120  also supports a fixture  154  that has bolts  156  being fixed but removably secured to the vise  102  by screwing the bolts  156  into threaded openings  158  on the upper surface  120 . The fixture  154  has a groove  160  at a bottom surface  162  to receive an upper portion of the wedge  124 . The block  130 , with the plate  126  attached thereto, is movable or shiftable in the horizontal direction (H), by turning the bolt  118 , so that blades can be captured and held between the plate  126  and the fixture  154 , as described in detail below. 
     A covering plate  164  is attached to a second end  166  of the vise  102  to provide dust and particle protection to the vice  102 . A bearing  168  is rotatably engaging the smooth section  142  of the bolt  118  that allows the bolt  118  to turn or rotate with minimum friction as rotatable or torque forces are applied to the bolt  118 . The inset  108  has the function of preventing the bearing  168  from moving in the horizontal direction (H) so that the bearing  168  is captured between the inset  108  and the flange  140 . 
     A U-shaped cover plate  170  is placed on top of the vise  102  to prevent or reduce dust and particles from moving into and through the vise  102 . 
     A motor mounting plate  172  is mounted by bolts  174  to the end  104  of vise  102  by screwing the bolts  174  into openings  176  at the end  104 . A lock-nut  178  is provided to prevent the bolt  118  from moving in the horizontal direction (H). The lock-nut  178  has a screw  180  that can be screwed against the bolt  118  to hold it in place. The motor mounting plate  172  attaches the motor  114  and gearbox  115  to the vise  102 . 
       FIG. 3  shows the blade holder  100  in an open assembled position (with the vise  102  removed for clarity) while  FIG. 4  shows the blade holder  100  in a closed position with a plurality of blades  182  held firmly between plate  126  and fixture  154 . Each blade  182 , such as a skate blade, is typically about 3 millimeters wide but other widths can also be used. The motor  114  rotates the shaft  112 , via gearbox  115 , a certain number of revolutions, which in turn, rotates the screw  118 . 
     The blade holder  100  is connected to a computer processor  184  that runs on software. As mentioned earlier, the processor  184  keeps, among other things, track of the number of revolutions the shaft  112  has been rotated. The processor  184  also monitors the torque force required to rotate the shaft  112 . While the blades  182  are loosely held between the plate  126  and the fixture  154  very little torque force of the motor  114  is required to turn the shaft  112  that is in operative engagement with the bolt  118  as the protrusion  152  engages the groove  150 . The threaded portion  136  is in threaded operative engagement with the threaded opening  134  of block  132  so when the threaded portion  136  is rotated, the block  132  moves horizontally away or towards the flange  140 . When a gripping side or engagement surface  121  of the plate  126  encounters and abuts the blades  182  to move the blades together the torque required to horizontally move the blades  182  increases. When all the blades  182  are in contact with one another, the torque required to further rotate the shaft  112  increases substantially to a threshold value. The processor  184  monitors the torque that is generated by the motor  114 . When the torque required reaches the threshold value, the processor  184  determines the number of blades  182  that are held between the plate  126  and fixture  152  because the processor  184  has received input regarding the thickness of each blade  182  and the initial distance between the plate  126  and the fixture  154 . The threshold value could be any suitable value such as 3-7 Nm. After the processor  184  has determined the number of blades  182  held by the blade holder  100 , the processor  184  determine the final torque value that must be reached to firmly hold the plurality of blades  182  during the sharpening procedure of the blades. The final torque value could, for example, be 5-11 Nm but higher and lower values can also be used. The higher the number of blades held the higher the final torque value should be. By knowing the number of blades  182 , the processor  184  also calculates the total width W of the set of blades  182 . This width W 1  wears on a first grinding section  187  of the rotating abrasive belt  186  as the rotating abrasive belt  186  grinds against the set of blades  182  to sharpen the blades. The belt  186  may have any suitable width such as 40 mm. After the sharpening of the blades  182  is complete, the processor  184 , preferably, shifts the vise  102  horizontally, to a distance that is equivalent to the width W 1 , so that a non-worn second grinding portion  189  of the sharpening belt  186  is positioned over the next set of blades  191  that are to be sharpened, as explained below. The fact that the vise  102  can be shifted prolongs the useful life of the abrasive belt  186  and it also ensures that the belt sharpens evenly i.e. it prevents the worn section  187  to engage a portion of the blades while a non-worn section  189  engages another portion of the set of blades. Instead, the vise  102  is shifted until the non-worn portion  189  is aligned on top of the new set of blades  191  that has a width W 2 . Preferably, the vise  102  is only shifted between the sharpening sessions of each new set of blades. It may also be possible for the processor  184  to require a shifting of the vise  102  after a certain time period (such as 500 seconds) or after a certain number of revolutions of the motor that drives the belt  186 . When the full width of the belt  186  has been used it is time to replace the belt  186  with a new non-worn belt. 
       FIG. 5  is a perspective view that shows the shifting mechanism on an underside of the blade holder  100 . The vise  102  rests on and is attached to a slide  190  that is slidable on a linear rail  192  wherein elongate protrusions  194  of the slide  190  follow the elongate grooves  196  on the rail  192 . A mounting bracket  198  is attached or secured to the slide  190 . The bracket  198  is attached to angled metal piece  200  by a bolt  202 . A bottom end  204  of the piece  200  is fastened to an elongate threaded piston or rod  206  by a threaded nut  208 . By rotating the nut  208  the nut  208  travels along the rod  206 . The rod  206  is in operative rotatable engagement with a linear actuator or electric motor  210  via a mounting bracket  212 . The actuator  210  is also connected to the processor  184 . The rod  206  has outside threaded portion  214  that is in operative engagement with inside thread  216  of the nut  208  so that when the rod  206  rotates the piece  200  moves away or towards the actuator  210  as the threaded rod  206  rotates inside the nut  208  that is secured to the bottom end  204 . The software is programmed to know how many rotations of the rod  206  are equivalent to the width W of the blades  182  to be sharpened. Because the piece  200  is connected to the vise  102  and slide  190 , horizontal movement of the piece  200  also moves the slide  190  relative to the rail  192 . As mentioned above, the grinding or sharpening of a first set of blades  182  wears a portion W 1  of the belt  186 . Upon completion of the grinding of the first set of blades, it is possible to shift the slide  190  horizontally sideways so that a new non-worn portion  189  is aligned with a new set of blades  191 , placed and firmly held between the plate  126  and the fixture  154 , that are to be sharpened. In this way, it is not necessary to replace the belt  186  each time a new set of blades is to be sharpened because a non-worn portion  189  of the belt  186 . In this way, the belt  186  can be used to sharpen many sets of blades until the entire width of the belt  186  is worn from grinding. 
     With reference to  FIGS. 7-8 , an elongate linear control unit assembly  300  includes an elongate control unit  302  that has a slide or rails  304  along which a contact wheel assembly  306  may slide. More particularly, underneath the linear control unit, the assembly  300  with a contact wheel is connected to the slide. The assembly  300  is fully computerized so that the processor  184  calculates and controls the movement of the various components of assembly  300  via computer programs. The assembly is very dynamic and can be used to profile and sharpen virtually any profile of the blades because the abrasive belt and the rollers are very adaptive and can follow and digitally register/record the profiles of the blades so there is no need to use physical templates. 
     The assembly  300  and processor  184  can thus be used to create profiling/grinding and sharpening programs based on the sensed or registered profiles by the contact wheel. It is to be understood that the ice skate blade grinding apparatus (made up of the blade holder  100  and the assembly  300 ) can also create virtually any profile because it is computer-driven that creates profiles based on software. In other words, the ice skate blade grinding apparatus may also be used to create virtually any profile of the blades by selecting a suitable sharpening/grinding program. 
     It is also possible to do test or reference runs so that the contact wheel may follow the contour or profile of the blades to be ground. In this way, the motor  308  acts as a spring when the contact wheel follows the profile of the blade assembly. This “sensing” step by the contact wheel is done without rotating the abrasive belt. In this way, the processor  184  can determine the location and profile of the blades by creating a reference program so that the processor  184  can calculate how to best grind the blades to create the desired profile. The processor  184  may be used to set different grinding pressures depending upon the number of blades that are to be ground or sharpened. The processor  184  may also adjust the speed of the sideways movement of the contact wheel depending upon how many blades are to be profiled/ground and the effect of the motor driving the abrasive belt. The motor effect and the sideways movement of the contact wheel are thus adjusted to one another to optimize the grinding along an optimized effect curve so that a constant grinding pressure can be used. When the maximum effect of the motor is required then the processor  184 , preferably, lowers the speed of the sideways movement of the contact wheel as the linear control unit moves horizontally so that the most optimal grinding results are accomplished. Preferably, the blades are fixedly held by the blade holder. The contact wheel is thus the part that is moving sideways. The processor  184  may also determine how worn the abrasive belt is and the particle size on the abrasive belt based on the performance of the belt as it is used for grinding the blades. Preferably, the abrasive belt is used for creating profiles of several blades that are held together by the blade holder. As described in detail below, the actual sharpening of a blade is, preferably, done by a disc that has the desired convex grinding shape and the blades are then sharpened one by one. The blade holder places or sideways shift the blade to be sharpened over the disc that has the selected shape radius. The software may be programmed with the position of each type of disc on the spindle so that blade holder can be shifted the correct distance to be placed over the desired disc. 
     One feature of the assembly  300  is that it is designed to be able to control the position of the contact wheel  320  and the spindle  322  both horizontally and vertically, as explained below. The vertical and horizontal positions are determined by the angle of the positioning axle  312  that is turned by the motor  308 . By using a gearbox  310  a high precision can be obtained as well as a high torque. Preferably, the contact wheel  320  is designed to follow a coordinate program to grind the bottom surface of the blades  332  that are held above the contact wheel  320 . This results in a function that has virtually no limitations regarding how the skate profile of the blades can be ground. More particularly, the assembly  306  includes an electric motor  308  in operative engagement with a gearbox  310 . A rotatable axle or rod  312  protrudes from the gearbox  310  through a bearing house  314 . The axle  312  is rotatably attached to an end of an arm  316 . The opposite end of the arm  316  is rotatably attached to an axle  318  that extends through a contact wheel  320  and an adjacent spindle  322  that has a plurality of grinding wheels  324  mounted thereon so that the contact wheel  320  rotates, the grinding wheels  324  rotate also. The construction of the spindle  322 , discs  324  and the contact wheel  320  enables the discs  324  and contact wheel  320  to be moved both in a horizontal and vertical direction along a circular path because of the linear control unit  302  as well as a result of rotating the axle  312 . The contact wheel  320  is thus eccentrically mounted relative to the axle  312  so that the second axle  318  is off-center or shifted away from the first axle  312 . This makes it possible to move the contact wheel  320  relative to the first axle  312  so that the exact position of the wheel  320  may be adjusted in the horizontal and vertical directions along the circular path by rotating the axle  312  in a first or a second opposite direction. Preferably, the contact wheel  320  may rotate freely because of its built-in double bearing construction. The assembly  300  also has a first adjustable roller  326  and a second roller  328  so that the contact wheel  320 , rollers  326 ,  328  may carry an abrasive belt  330 . The roller  328  is in operative engagement with a motor  329  that drives the abrasive belt. Preferably, the roller  326  is adjustable to create a tension of the belt  330  and adjusts its position to horizontal and vertical movement of the contact wheel  320  in engagement with the non-elastic belt  330  when the contact wheel  320  follows the profile of the blades to be profiled or sharpened. The rotatable abrasive belt  330  may be used to grind the blades  332 . The vertical movement of the contact wheel  320  and spindle  322  is fully controlled by the electric motor  308 . 
     With reference to  FIGS. 9 and 16-17 , an ice skate sharpener or manual belt grinding profiling machine  400  is shown that may be used to simultaneously profile 1-6 ice skate blades, stacked next to one another. Only one blade is shown in the figures. One of the most important features of the present invention is that it is possible to copy a profile of a template to ice skating blades even though the template profile is quite complicated. The underside, profile of the template may have any suitable profile and this makes the present invention very versatile. Another important feature is the mechanism associated with the belt rollers provides adjustments of movement, belt tension and pressure in one system. 
     The machine  400  has a motor-driven belt  402  with three-wheel hubs  410 ,  412  and  414  that are in operative engagement with the rotatable belt  402 . A motor  408  drives the driving wheel  410  to drive and rotate the belt  402  about hubs  412 ,  414 . Preferably, the hubs or wheels  412 ,  414  are mounted on a Y-axis linear-guide rail  416 , supported by hydraulic gas springs for grinding pressure, movement compensation and for maintaining a solid and consistent belt-pressure during the grinding procedure. 
     The machine  400  has a handle  450  that is used to lock, tighten and secure the blades  406  to be profiled or machined so that the blades  406  are firmly held in the vise  432  of the machine  400  during the grinding or profiling operation. 
     In order to mount the skate blades  406  into the machine  400 , a tiltable vise  432  is mounted on a linear guide or rail  426  (X-axis). The vise  432  may be moved back and forth on the rail  426  in the x-direction. More particularly, the bottom of the vise  432  has a pair of rollers  452 , mounted below a plate  453 , that are held to the rail  426  and enable the vise  432  to slide along the rail  426 . The vise  432  is tiltable relative to the plate  453  at hinges  455  to an open position to make it easier to set up and mount the blades  406 . Once the blades are clamped in the vise  432 , the vise  432  is tilted back to the closed position and locked in its horizontal grinding position. 
     The blade grinding and profiling copy system  418  is mounted in the front of the vise  432 . The system  418  is adjustable in both the x- and y-directions for exact positioning of a guide roll  424  relative to an underside profile  420  of the template  404 . The profile  420  has thus a profile shape or curvature as seen from the side. Preferably, the template  404  should be longer than the blades  406  so that it is only necessary for the guide roll  424  to follow a portion of the underside  420  of the template  404  in order to grind the entire underside  422  of the blade  406 . During the set up, it is also determined which percentage (often between 50-75%) of the length of the template  404  is to be transferred or copied to the blade or blades  406 . During the grinding operation of the blade  406 , as long as the guide roll  424  does not roll on the underside profile  420  of the template  404 , material is being ground of the underside  422  of the blade  406 . When the guide roll  424  can roll on the profile  420  then no surface or material is ground off the blade or blades  406 . 
     A key features of the present invention is thus the efficient profiling of the blade  406  because the shape of the underside profile  420  of the template  404  is copied to the underside  422  of the ice skate blade  406  by moving the vise  432  back and forth so that the rotatable belt  402 , mounted on the rotatable rolls  410 ,  412 ,  414 , grinds the underside  422  while the position of the grinding roll  414  and the grinding belt  402  are guided by guide roll  424  that, at the same time, is urged against to follow the profile of the underside profile  420  of the template  404 . This is possible because the grinding roll  414  and the guide roll  424  are mounted to the same axle  444  but there is a distance (D) between the two rolls  414  and  424 . The grinding roll  414  is generally wider than the guide roll  424  so that it can support a wider belt  402  to profile a plurality of blades  406  that are mounted next to one another, The idea of copying the profile of templates onto the blades means the profiles of the skate blades may be shaped into many different radiuses or shapes in a controlled fashion to suit each individual unique requirement. 
     When the blades  406  are mounted, the vise  432  is tilted into a forward position (best seen in Fla  11 ) for easy access to mount the blades  406  therein. The vise  432  is then put back into the horizontal position and the lockable adjusting bolts  433  on each side of the vise  432  are tightened, 
     The blades  406  are thus put into and centered in the vise  432  when the vise is in the open tilted position. 
     The template  404  is then mounted into the template holder  440  by tightening locking Knobs  442 . Preferably, a threaded elongate portion of the knobs  442  extend through cavities or grooves  446  in the template  404  and rest at the bottom of the grooves  446 . The template may be adjusted into position by turning the top knob  448 . mounted on top of the vise  432 , to raise or lower the template  404  relative to the blades  406  and the guide roll  424  that is fixed in the y-direction on the rail  416 . In this way the template  404  is raised or lowered relative to the blades  406  in order to minimize the amount of material that must be removed from the blades  406  in order to make the underside  422  obtain the same profile as the underside profile  420  of the template  404 . It is also possible to adjust the template  404  sideways (x-direction) in a limit way. 
     The template holder  440  and vise  432  are then moved back and forth a few times in order to set the amount of surface to be removed from the blades  406 , When the template  404  is moved back and forth (without having started the motor  408 ), the guide roll  424  indicates, by looking at the position of the grinding roll  414  relative to the underside  422 , how much surface from the blades will be removed once the motor  408  is turned on to rotate the belt  402  and the guide roll  424  follows the underside  422  of the template  404  so that the belt  402  starts grinding off material from the underside  422  of the blade or blades  406 . 
     After the position of the template  404  is set, the grinding motor  408  is turned on to start the rotation of the grinding belt  402 . The vise  432  is then moved back and forth on the rail  424  while placing the operator places his/her hand on the clamping handle  450 . The back and forth movement of the vise  432  is repeated until grinding procedure is finished i.e. when no more surface is removed from the underside  422  of the blades  406  even though the vise  432  is moved back and forth while the guide roll rolls against the underside  420  of the template  404 . The profile of the blade  406  is done when the guide roll can be rolled against the entire length of the template  404  without removing any additional surface or material from the blade  406 . The grinding motor  408  is then stopped. The vise  432  is unlocked with the lockable adjusting bolts  433 . The vise  432  is then tilted upwardly (as shown in  FIG. 11 ), the grinding result on the blades is checked before removing the skate blades  406  from the vise  432 . In order to make a complete finish of the underside profile  420  of the blades  406 , a final sweep against the grinding belt  402  is often carried out without using the template. This blending step is to even out the finish of the profiled area or underside profile  422  of the blade  420 . 
     With reference to  FIG. 12 , the template  404  has a front portion  470  and a back portion  472 . This means the profile of the front portion  470  determines the profile of the front portion of the blade  406  and the back portion determines the profile of the back portion of the blade  406 . For example, the profile  420  may a profile that is equivalent to a portion of a periphery  454  of a circle  456 . In other words, the circle  456  is applied to the template  404  then cut to fit the bottom part of the template  404  so that the profile  420  is the same as the periphery  454  of the circle  456 . The radius  457  of circle  456  may be very large such as 4 meter or any other suitable radius. The length of the template  404  may be about 450 millimeters or any other suitable length. 
     The underside profile  420  may also be a combination of profiles so that it is a combination of more than one profile.  FIG. 13  shows a template  404  that has a dual radius profile as the underside profile  420 . This means a right-side half  458  of the profile  420  has a profile that is equivalent to the periphery of a section of a circle  460  with a radius  462  while the left-side half  464  of the profile  420  has a profile that is equivalent to the periphery of a section of a smaller circle  466  that has a radius  468  that is smaller than the radius  462 . 
       FIG. 14  shows a template  404  wherein the underside profile  420  consists of a combination of three difference radii i.e. a section of a circle  474  that has a periphery that corresponds to the curvature or profile in section  476 , a section of a slightly smaller circle  478  that has a periphery that corresponds to the curvature in section  480  and a section of a smallest circle  482  that has a periphery that corresponds to the curvature in section  484 . Preferably, the very front part  486  of the template  404  is straight and has no curvature. The transition between the various sections of different curvature is seamless. The radiuses may be pitched from the center point and make up for different percentage of the overall template, 
       FIG. 15  shows a template  404  wherein the curvature of the underside profile  420  is equivalent to the shape of an ellipse or conical section  488  so that the shape of the underside  490  of the ellipse  488  is the same as the shape of the profile  420 . The relative position of the blade  406  to the template  404  is such that the blade  406  is centered to the template  404  but the position may be adjusted sideways when necessary. 
     Reference is now made to  FIG. 19 , which shows an operating environment for the processor  184 . Specifically, the processor  184  can be part of a computing apparatus  800  integrated within the ice skate blade grinding apparatus. In addition to the processor  184 , the computing apparatus  800  also comprises a memory  820 , a network interface  850  and a user interface  860 . These components may be interconnected by a communication bus  855 . The user interface  860  may include a graphical user interface (GUI), such as a display and/or a touchscreen. The network interface  850  allows the computing apparatus  800  to communicate over a data network  870 , such as the Internet, a local area network, a wide area network and/or a wireless network. 
     The computing apparatus  800  may also include a plurality of sensors. One example of a sensor is a rotation sensor  1010  that senses the number of rotations or angular distance covered by the shaft  112 . As explained above, by keeping track of the number of rotations of the shaft  112 , it is possible to determine how much the plate  126  has been shifted horizontally relative to the fixture  154  and how big the gripping gap  119  is. Another example of a sensor is the aforementioned position sensor  1020  for determining the size of the gap  119  by sensing the position of the plate  126 , which avoids having to measure the number of rotations of the shaft  112 . A further example of a sensor is a camera  1030  that captures optical images of the gap  119  and or the skate blades therein, possibly capturing the ice contacting surface of the skate blades visible from an underside thereof. Another example of a sensor can include a pressure sensor  1040  that is placed on the engagement surface  121  of the plate  126  or on the opposite engagement surface  123  the fixture  154 . Further examples of sensors can be provided. Of course, not all sensors need be present in all embodiments. 
     The memory  820  may be a non-transitory memory medium that stores instructions  830  and also stores data  840 . The memory medium may be, but is not limited to, an electronic storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. A non-exhaustive list of more specific examples of the memory medium includes the following: a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), a static random access memory (SRAM), a portable compact disc read-only memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a floppy disk, a mechanically encoded device such as punch-cards or raised structures in a groove having instructions recorded thereon, and any suitable combination of the foregoing. A computer-readable storage medium, as used herein, does not include transitory signals per se, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through a waveguide or other transmission media (e.g., light pulses passing through a fiber-optic cable), or electrical signals transmitted through a wire. 
     The instructions  830  include computer-readable program instructions that define operation of the processor  184 . The program instructions can be downloaded to the memory  820  from an external computer or external storage device via the network interface  850 . The network interface  850 , which can be embodied as a network adapter card or other network interface, can receive the program instructions over the network  870  and forward them to the memory  820  for storage and execution by the processor  810 . 
     The program instructions may be assembler instructions, instruction-set-architecture (ISA) instructions, machine instructions, machine dependent instructions, microcode, firmware instructions, state-setting data, or either source code or object code written in any combination of one or more programming languages, including an object-oriented programming language such as Smalltalk, C++ or the like, and conventional procedural programming languages, such as the “C” programming language or similar programming languages. In some embodiments, electronic circuitry including, for example, programmable logic circuitry, field-programmable gate arrays (FPGA), or programmable logic arrays (PLA) may execute the program instructions by utilizing state information to personalize the electronic circuitry, in order to carry out aspects of the present disclosure. 
     Execution of the program instructions by the processor  184  results in the ice skate blade grinding apparatus (e.g.,  400 ,  100 ,  300 ) carrying out aspects of the present disclosure, such as one or more processes. The data  840  stored in the memory  820  comprises data needed to support execution of the one or more processes executed by the processor  184 . 
     As such, the memory  820  comprises computer-readable instructions  830  which, when read and executed by the processor  184  of the ice skate blade grinding apparatus, cause the ice skate blade grinding apparatus to carry out a variety of processes. 
     One such process includes a parameter variation process (see  FIG. 18 ), according to which the processor  184  determines a number of contiguous ice skate blades  182 ,  332  inserted into the holding mechanism  100  of the ice skate blade grinding apparatus (step  910 ), and then sets (and/or varies) an operating parameter of the ice skate blade grinding apparatus based at least in part on the determined number of contiguous ice skate blades (step  920 ). 
     The ice skate blades  182 ,  332  can be stacked against one another (contiguous) and held by the holding mechanism  100 . In order to determine the number of how many blades  182 ,  332  are held together, various approaches may be used. 
     In some approaches, the camera  1030  captures at least one image of an ice-contacting surface of the blades inserted into the gap  119  of the holding mechanism  100 . With reference to  FIG. 20 , an image  1100  is processed by the processor  184  to identify/detect inter-blade surface transitions  1110 , i.e., transitions between adjacent ones of the blades  182 , while looking at the ice-contacting surface of the blades. An image processing algorithm may be used for this purpose. The number of contiguous ice skate blades  182  can then be determined as one more than the number of transitions detected, i.e., if the number of detected inter-blade transitions is N, then then number of blades is N+ 1 . For example, as seen in  FIG. 20 , the number of inter-blade transitions  1110  is three, and the number of blades  182  is four. In other embodiments, the camera can be positioned to view the blades from the perspective of the blade holder, i.e., from the side opposite the ice-contacting surface of the ice skate blades. 
     In other approaches, the user may provide input via the user interface  860 . Such input may include the number of contiguous (stacked) ice skate blades, the thickness of one or more (or each) of the blades, the average thickness of each blade, the manufacturer and/or model of one or more (or each) of the blades, the type of blade (e.g., hockey or figure skating), the material (such as steel or composite, for example) and other inputs. This information allows the processor  184  to set a target value of the operating parameter. 
     In terms of the operating parameters that can be set (and therefore also varied) based at least in part on the number of contiguous ice skate blades determined to have been inserted into the ice skate blade grinding apparatus and/or held by the holding mechanism  100 , one example of such operating parameter is the final gripping force (or torque value or clamping pressure) applied by the plate  126  and fixture  154  to the blades  182 ,  332 . The gripping force, torque value and/or clamping pressure can be made dependent on how many blades are held together. Specifically, the processor  184  monitors the torque that is generated by the motor  114 . When the torque required reaches the threshold value, the processor  184  determines the number of blades  182  that are held between the plate  126  and fixture  152  because the processor  184  has received input regarding the thickness of each blade  182  and the initial distance between the plate  126  and the fixture  154 , The threshold value could be any suitable value such as 3-7 Nm, After the processor  182  has determined the number of blades  182  held by the blade holder  100 , the processor  184  determine the final torque value that must be reached to firmly hold the plurality of blades  182  during the sharpening procedure of the blades. The final torque value could, for example, be 5-11 Nm but higher and lower values can also be used. 
     Another example of an operating parameter that can be set includes the desired pressure to be applied by the grinding mechanism  300  (e.g., via the abrasive element). Specifically, the processor  184  may be used to set different grinding pressures depending upon the number of blades that are to be ground or sharpened. This could include the pressure applied by the belt  186 ,  330  via the contact wheel  320 . This could also include the pressure applied by any of the grinding wheels  324 . A feedback loop may be created between the processor  184  and the pressure sensor  1040  (which in this embodiment would detect the pressure applied to the holding unit from underneath, in the orientation of  FIG. 7 ) to determine how much pressure is being applied and whether this meets the desired pressure (which could be a desired minimum pressure or maximum pressure or a combination thereof). In this way the grinding pressure of an abrasive element is made dependent on the number of blades to be ground and/or on the collective thickness resulting from the presence of multiple contiguous (stacked) blades. 
     A further example of an operating parameter that can be set can include a feature (e.g., speed or acceleration) of the relative movement between the abrasive element and the blades  182 ,  332 . For example, in the embodiment where the arm  316  and the abrasive element is moved along the rails  304  and the blades  182 ,  332  remain fixed, the motor that causes movement of the arm  316  and the abrasive element can have a speed and/or movement program (which can include but is not limited to curves of speed versus distance, speed versus time, acceleration versus position, etc. stored as part of the data  840  in the memory  820 ) that is governed by factors including the number of contiguous blades  182 ,  332 , and the collective thickness of those blades. That is to say, at least one feature of the movement pattern (e.g., speed, acceleration) is different when there is only one blade compared to when there are two blades, and compared to when there are three blades, etc. 
     Another example of such operating parameter that can be set based on the number of stacked blades is the profile that is imparted to the blades. Multiple profiles can be held as part of the data  840  in the memory  820 , and each may be associated with a different number of skate blades, so that the one associated with the determined number of blades is the one used to profile the skate blades. 
     As such, in some embodiments, the collective thickness of the contiguous ice skate blades (which depends on the number of ice skate blades and their individual thicknesses) can be determined/measured, and the operating parameter can be set based on the collective thickness so determined/measured. In order to determine the collective thickness, at least one image of the ice skate blades can be captured by the camera  1030  and the collective thickness can be measured from the at least one image. This image may be from the underside of the blades or even from above. 
     In another embodiment, the collective thickness can be determined by measuring the individual thickness of each of the ice skate blades and then adding the individual thicknesses to yield the collective thickness. In this case, to determine the individual thickness of a given one of the ice skate blades, the camera  1030  may capture at least one image of the given ice skate blade and then the processor  184  can apply an image processing algorithm to measure the thickness of the given ice skate blade from the at least one image. Alternatively, the individual thickness of a given one of the ice skate blades can be determined based on input received from a user of the apparatus via the user interface  860 . Such input can specify the thickness of the given ice skate blade, or the manufacturer and model of the blade, which is associated with a thickness (e.g., in the memory  820  or obtainable over the network  870 ). 
     It should be appreciated that since the blades are held in place by the holding mechanism  100  of the ice skate blade grinding apparatus, and in the case where at least part of the holding mechanism  100  (e.g., the movable block  132 ) is movable along an axis (e.g., of the threaded bolt  118 ), determining the collective thickness of the blades could comprise logging a position of the holding mechanism along such axis, based on a reading from the position sensor  1020 . Specifically, this would give an inferred measure of the size of the gap  119 . Alternatively, instead of measuring the linear position of the movable block  132 , the rotation sensor  1010  could measure an angular distance traveled by a knob (similar to  442 ) between an initial position and a final position in which the ice skate blades are clamped (possibly with a force or torque at or above a given threshold). 
     Thus, there has been described and illustrated an ice skate blade grinding apparatus, comprising a holding mechanism  100  configured to hold one or more ice skate blades under pressure; a grinding mechanism  300  connected to the holding mechanism  100 , the grinding mechanism  300  configured to cause an abrasive element (e.g., belt  330 ) to move relative to, and contact under pressure, an ice-contacting surface of the blades  182 ,  332 ; and a processing entity  184  configured for controlling a set of operating parameters. The processing entity  184  is further configured to determine the number of ice skate blades  182 ,  332  held together by the holding mechanism  100 , and is also configured to set at least one of the operating parameters based at least on the determined number of contiguous ice skate blades  182 ,  332  held by the holding mechanism  100 . The disclosed apparatus and method allows optimized sharpening and profiling of multiple blades at a time, since the operating parameters that are optimal for a single blade are not necessarily the same for multiple blades being sharpened or profiled together. 
     Aspects of the present disclosure are described herein with reference to flowcharts and block diagrams of methods and apparatus (systems), according to various embodiments. It will be understood that each block of the flowcharts and block diagrams, and combinations of such blocks, can be implemented by execution of the program instructions. Namely, the program instructions, which are read and processed by the processor of the aforementioned computing apparatus, direct the processor to implement the functions/acts specified in the flowchart and/or block diagram block or blocks. It will also be noted that each block of the flowcharts and/or block diagrams, and combinations of such blocks, can also be implemented by special purpose hardware-based systems that perform the specified functions or acts or carry out combinations of special purpose hardware and computer instructions. 
     The flowcharts and block diagrams illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present disclosure. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of instructions, which comprises one or more executable instructions for implementing the specified logical function(s). In some alternative implementations, the functions noted in the block may occur out of the order noted in the drawings. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. 
     The descriptions of the various embodiments of the present disclosure have been presented for purposes of illustration and are not intended to be exhaustive or limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The terminology used herein was chosen to best explain the principles of the embodiments, the practical application or technical improvement over technologies found in the marketplace, or to enable others of ordinary skill in the art to understand the embodiments disclosed herein. 
     It should be appreciated that throughout the specification, discussions utilizing terms such as “processing”, “computing”, “calculating”, “determining”, “analyzing” or the like, can refer to the action and/or processes of a computer or computing system, or similar electronic computing device, that manipulate and/or transform data represented as physical, such as electronic, quantities into other data similarly represented as physical quantities. 
     As used herein, unless otherwise specified, the use of the ordinal adjectives “first”, “second”, “third”, etc., to describe a common object or step, merely indicate that different instances of like objects or steps are being referred to, and are not intended to imply that the objects or steps so described must be in a given sequence, either temporally, spatially, in ranking, or in any other manner. 
     It is noted that various individual features may be described only in the context of one embodiment. The particular choice for description herein with regard to a single embodiment is not to be taken as a limitation that the particular feature is only applicable to the embodiment in which it is described. Various features described in the context of one embodiment described herein may be equally applicable to, additive, or interchangeable with other embodiments described herein, and in various combinations, groupings or arrangements. In particular, use of a single reference numeral herein to illustrate, define, or describe a particular feature does not mean that the feature cannot be associated or equated to another feature in another drawing figure or description. 
     Also, when the phrase “at least one of A and B” is used, this phrase is intended to and is hereby defined as a choice of A or B or both A and B, which is similar to the phrase “and/or”. Where more than two variables are present in such a phrase, this phrase is hereby defined as including only one of the variables, any one of the variables, any combination of any of the variables, and all of the variables. 
     The foregoing description and accompanying drawings illustrate the principles and modes of operation of certain embodiments. However, these embodiments should not be considered limiting. Additional variations of the embodiments discussed above will be appreciated by those skilled in the art and the above-described embodiments should be regarded as illustrative rather than restrictive. Accordingly, it should be appreciated that variations to those embodiments can be made by those skilled in the art without departing from the scope of the invention.