US 3827185 A
Apparatus for the sharpening of ice skates is disclosed. The apparatus consists of a carriage assembly having clamping means thereon for clamping a pair of skates to be sharpened. The carriage assembly is mounted for reciprocal longitudinal movement on a track carried by suitable framing and during forward and rearward movement of the carriage it passes over rotating grindstones which sharpen the skate blades. Each sharpening grindstone is independently pivotally mounted whereby the grindstones are lowered upon contact by the skate blades to follow the profile of the skate blade during forward movement of the carriage. The grindstones or grinding wheels may contact and further sharpen the skate blades during rearward movement of the carriage, or the grindstones may be lowered out of contact with the blades during rearward movement. Preferably the unit is provided with a cover to completely enclose the operating mechanism during operation for safety. The apparatus may be provided with a suitable microswitch which will not permit operation of the apparatus until the cover is completely closed. Uniform sharpening of skate blades is obtained as the blades travel over the sharpening grindstones at a uniform rate of speed and the pressure applied by the grindstone against the blades are constant throughout the sharpening operation.
Claims available in
Description (OCR text may contain errors)
llnite States  3,827,185 Aug. 6, 1974 ICE SKATE SHARPENING APPARATUS Jack Smith, Ontario, Canada  Assignee: Eddy Match Company, Limited,
Toronto, Ontario, Canada  Filed: July 26, 1972  Appl. No.: 275,195
 Foreign Application Priority Data  Field of Search 51/92 R, 92 BS, 99, 74 R, 51/74 BS, 228, 2 F, 5, 34, 231; 76/83  References Cited UNITED STATES PATENTS 1,487,142 3/1924 Boker 51/92 R X 2,438,543 3/1948 Custin et a1 51/217 R 2,477,418 7/1949 Polk 51/2 F 3,052,068 9/1962 Burgess 5l/l28 X 3,525,180 8/1970 Hillier 51/92 R 3,691,898 9/1972 Held 51/5 X 3,709,096 1/1973 Stender-Roberts. 51/99 X 3,724,766 4/1973 Bosland 241/36 X Primary Examiner-Al Lawrence Smith Assistant Examiner-Nicholas P. Godici [5 7 ABSTRACT Apparatus for the sharpening of ice skates is disclosed. The apparatus consists of a carriage assembly having clamping means thereon for clamping a pair of skates to be sharpened. The carriage assembly is mounted for reciprocal longitudinal movement on a track carried by suitable framing and during forward and rearward movement of the carriage it passes over rotating grindstones which sharpen the skate blades. Each sharpening grindstone is independently pivotally mounted whereby the grindstones are lowered upon contact by the skate blades to follow the profile of the skate blade during forward movement of the carriage. The grindstones or grinding wheels may contact and further sharpen the skate blades during rearward movement of the carriage, or the grindstones may be lowered out of contact with the blades during rearward movement. Preferably the unit is provided with a cover to completely enclose the operating mechanism during operation for safety. The apparatus may be provided with a suitable microswitch which will not permit operation of the apparatus until the cover is completely closed. Uniform sharpening of skate blades is obtained as the blades travel over the sharpening grindstones at a uniform rate of speed and the pressure applied by the grindstone against the blades are constant throughout the sharpening operation.
2 Claims, 13 Drawing Figures 248 Ela W ui I "A": l l
PATENTEDAUB 61914 I SHEET 1 OF 6 PATENTEDMJE 61w 3,827,185
SHEET IMF 6 ICE SKATE SHARPENING APPARATUS satisfactorily sharpen ice skates.
Many people enjoy the sport of ice-skating but because of the lack of suitable sharpening facilities much of the skating is done on skates which are somewhat less than sharp with a resultant decrease in enjoyment. Under present situations known to the applicant it is necessary for a person to take his or her skates to a shoemaker or hardware store for sharpening and this is inconvenient particularly when one must wait, in some instances a considerable length of time, for the job to be finished or must leave the skates to be picked up again at a later time.
It is the desire of the applicant to provide a machine apparatus which may be conveniently placed in arenas or other handy locations and which may be coinoperated and semi-automatic or fully automatic in operation and which will enable any person to quickly and easily sharpen ice skates and be completely safe for use by all people including children.
Additionally the apparatus of the invention may be used by equipment managers of professional or amateur ice hockey teams as a permanent installation in equipment and maintenance rooms in arenas or ice hockey palaces, or may be operated by the players themselves for sharpening their own skates without previous training or experience in skate-sharpening procedure.
As above indicated the apparatus may also be placed in an arena or at any other outdoor skating rink for use by the general public as no skill is required to operate the apparatus.
It is difficult to properly sharpen a pair of ice skates, and using known procedures a skate can only satisfactorily be sharpened by a skilled person. In the past and in some instances a procedure which is still carried on today is for a shoemaker or equipment manager to simply manually hold a skate and pass it across a rotating grindstone. To obtain a satisfactory sharpness by such a method requires considerable skill and cannot be practised by the average athlete or layman.
Other and more sophisticated skate sharpening apparatus consists of a swing type of holder into which a skate is secured by the operator, who in order to sharpen the skate moves the skate backwardly and forwardly over a rotating grindstone. Others operate on a similar principle but have a skate tightened in a stationary clamp and a movable grinding wheel which is moved relative to the stationary skate blade.
Other skate-sharpening tools of smaller dimensions are available which a person can rub on a skate blade. These are usually in plastic or wooden holders and if anything produce only a very superficial sharpening.
In the aforementioned methods and apparatus there is the danger either of applying uneven pressure to the blade or an inconsistent speed at which the blade or grinder move with respect to each other. Unless great care is exercised resulting irrepairable damage to the skate blade can result. Many young skaters and hockey players do not possess or are unable to operate existing sharpeners with the result that a good sharp pair of skates cannot be maintained.
The disadvantages of known skate sharpening devices are overcome by the present invention which provides means for the sharpening of one or a pair of skates whereby the skate or skates are clamped in a carriage and clamping assembly which is movable reciprocally over a sharpening assembly. The carriage assembly moves over the sharpening assembly at a constant rate of speed and grinding wheels of the sharpening assembly are held against the moving skate blades with a uniform pressure to insure a uniform and even sharpening of the blades throughout their lengths. The grinding wheels employed may either have a completely flat or a somewhat convex configuration in transverse cross-section whereby the sharpening imparted to the skate blade may either be completely flat in cross-section or provide to the skate blade a uniform concave or hollow ground sharpening finish which is desired by some skaters.
As the operation of the present apparatus is preferably electrically operated a constant speed of travel and uniform application of grindstone pressure is ensured so that the apparatus can be operated by any person skilled or unskilled, or even a child without the necessity of a skilled operator being present. Inasmuch as the operation of the apparatus may be completely automated it can be operated even by youngsters in complete safety and with the knowledge that the sharpened skates will meet with their complete approval.
In one preferred embodiment the apparatus is provided with a cover and suitable means to prevent operation until the cover is completely closed thus ensuring safety of operation both from the standpoint of grinding particles and the inadvertent inclusion of fingers or hands in the operating mechanism.
A further embodiment contemplates the use of a coin-receiving mechanism wired in the circuitry of the apparatus which prevents operation until a coin, which could be of any suitable denomination, is inserted. Suitable coin-receiving mechanisms are well known and need not be further described in this specification.
In using a coin-operated version of the invention, an operator first opens the cover of the apparatus and positions a skate or skates in the carriage and clamping mechanism, and then clamps the skates in the carriage. Once the skates are clamped in position, the cover is then lowered to enclose the whole assembly and a coin is then deposited in the mechanism and the depositing of the coin either immediately starts the machine in operation or the operator would then push a start button to commence operation. In operation the carriage carries the skates one, or two or more times in reciprocal motion over rotating grinding wheels or stones to impart a sharpening to the skate blades. Whether the carriage passes once or twice or more over the grindstones depends upon the programming of the machine which iswell within the skill of one knowledgeable in the art, but it has been found that a forward and backward pass over the grindstones is usually quite sufficient.
After the sharpening operation is completed the machine automatically stops and the operator simply lifts the cover and unclamps and removes the sharpened skates. When a cover is used on the skate sharpening apparatus, a suitable microswitch arrangement can be installed to break tthe machine circuitry until the cover is closed to prevent inadvertent operation of the apparatus when the cover is open.
The main object of the present invention then is to provide a skate sharpening apparatus for the sharpening of one or more skates and which can be operated in complete safety by a person unskilled in such art. The machine of the invention consists of a carriage including a clamping mechanism into which one or a pair of skates is clamped and then by means of an electric motor the carriage is reciprocally moved at a uniform speed over one or two rotating grinding wheels which are held against the passing blades by uniform pressure to ensure a uniform and even sharpening of the skate blades.
It is a further object of the present invention to provide a skate sharpening apparatus which is safe in operation and which may be operated by an unskilled operator or even a child and which will sharpen a skate or a pair of skates to a degree of sharpness desired by the skater.
A skating assembly consists of a boot and a tubeblade or fancy-skate blade arrangement fastened to the boot, and for purposes of brevity, this assembly will throughout this disclosure and claims he referred to simply as being a skate.
In one embodiment the grindstones contact the skate blades during both forward and rearward movement of the carriage and clamping assembly, while in a further embodiment the grindstones are held in a lowered position during rearward movement of the carriage.
The invention will now be discussed in more detail with reference to the accompanying drawings in which like numbers refer to like parts and wherein:
FIG. 1 illustrates in perspective view an ice skate blade sharpening assembly according to one embodiment of the present invention;
FIG. 2 is a bottom view of the platform shown in FIG.
FIG. 3 is a bottom view of the carriage and clamping assembly illustrated in FIG. 1;
FIGS. 4a and 4b are diagrammatic side views in reduced scale of the carriage and clamping assembly in two positions during its path of travel;
FIG. 5 is an enlarged side view of a drive chain connected to a flange carried by the carriage and clamping assembly to effect reciprocal movement of the carriage;
FIG. 6 is an enlarged end view of a suitable arrangement for bearing against a skate blade after the grindstone sharpening to remove any slight burr which might remain along the edges of the skate blade; and
FIG. 7 is a perspective view of a further embodiment of the skate sharpening apparatus according to the present invention;
FIG. 8 is a plan view of two sharpening assemblies for use with the machine shown in FIG. 7 each being independently pivoted and each having an independently driven grinding wheel;
FIG. 9 illustrates in top plan view a further embodiment of a suitable clamping assembly; and
FIG. 10 is a sectional view taken along line 10-10 of FIG. 9;
FIG. 11 illustrates in sectional view a portion of the frame assembly shown in FIG. 7 with alternative means for lowering a grinding wheel out of contact with a skate blade during return travel of the clamping and carriage assembly;
FIG. 12 illustrates in partial sectional view a component part of the assembly shown in FIG. 11.
Referring now to the drawings the assembly consists of suitable framing (not numbered) having a platform assembly 2, and parallel and longitudinal tracks or rails 4 carried by the platform. A carriage and clamping assembly 6 provided with wheels or rollers 8 (see FIG. 3) is mounted for reciprocal to and fro movement on the tracks 4 as will be described in more detail below.
For purposes of safety of operation the apparatus may be provided with a top 10 and a closure cover 12 with a hinge 14 to permit opening and closing and hold open lever assemblies 16.
The upper surface of the carriage assembly 6 is provided with two longitudinal slots 18 to receive the blades of skates which are to be sharpened. For purposes of illustration only the boot portions 20 of a pair of skates ready to be sharpened are shown in position in phantom lines in FIG. 1.
The skate blades are clamped in the carriage assembly 6 in the following described manner with reference to FIG. 3 which illustrates the carriage assembly in bottom view. Beneath the slots 18 and adjacent the outside of the carriage assembly 6 are secured two stationary clamping blocks 22 having inwardly directed clamping edges or surfaces 24. The clamping blocks may be secured to the carriage assembly 6 by means of bolts 26.
A central support 28 carries two movable clamping blocks 30 having outwardly facing clamping edges or surfaces 32. Each of the movable clamping blocks 30 is slidably mounted in the central support 28 for movement in the directions of the arrows 34. Arms 36 are pivotally secured to each movable clamping block 30 and extended inwardly from the movable clamping blocks, and opposite arms from each of the movable clamping blocks are pivotally secured together by linkage members 38 and pivot pins 40. A clamping rod 42 passes through the linkage members 38 and is securely fixed thereto by welding or the like. The rod 42 is rotatably held by retaining member 44, and the rod bends upwardly to pass through slot 46 in the surface of the carriage to provide a clamping lever 48 as clearly shown in FIG. 1. It will be appreciated that movement of the clamping lever 48 in the direction of the arrow 50 in FIG. 1 will effect movement of the movable clamping blocks away from the stationary clamping blocks 22. Moving the lever 48 in the direction opposite to arrow 50 will cause the clamping surfaces 32 to close towards the clamping surfaces 24 and clamp a skate blade therebetween. It has been found that this clamping arrangement with the clamping lever in a just over center" position securely maintains the skates in position and that continued pressure on lever 48 is not necessary to maintain clamping pressure. In order to stop movement of the movable clamping blocks in the just over center" position an adjusting bolt 39 carried by the platform 6 to limit the rotation of the clamping rod 42 in the clamping direction. The positioning of the bolt 39 is shown in FIGS. 1 and 3, and of course adjustment of the bolt against which linkage members 38 abut will limit the extent of rotation of the clamping rod 42 and the outer clamping movement of the movable clamping blocks 30.
The clamping rod 42 is provided with a deflecting plate 52 the purpose of which will be described later.
While one specific arrangement for clamping the skate blades in the carriage assemlby is discussed and shown in FIG. 3 it will be appreciated that various other clamping arrangements could be utilized without departing from the scope of the present invention.
At the end of each slot 18 the carriage assembly carries dressing stones 54. The dressing stones 54 may be held in position by simply sliding the stones into openings defined by flanges 54 and tightening the bolts 58 shown in FIG. I. The purpose of the dressing stones is to ensure that the surfaces of the grindstones which contact the skate blades are maintained in desired condition. If it is desired that the grinding surface of the grindstone be flat to impart a flat sharpening to a skate blade then the dressing stones will also have a flat surface for presentation to the grindstone. If however the grinding edges of the grindstone are provided with a slight convex configuration in cross-section to impart a slightly concave or hollow ground cross-section configuration to a sharpened skate blade, then the dressing stones 54 will have a slightly concave configuration to maintain the edge of the grinding stone with a slightly convex sharpening edge. At one time it was considered preferable that all skate blades should be sharpened with a concave or hollow-ground cross-section configuration, but recent practice is that a skate blade having a flattened edge is preferred.
By means of wheels or rollers 8 the carriage 6 is mounted for reciprocal movement along the tracks 4 provided on platform 2 as shown in FIG. 1.
FIG. 2 illustrates the platform 2 in bottom view.
The grinding wheels or grindstones 60 shown in FIG. 1 are rotatably carried by lever arms 62 which are independently pivotally secured to the underside of the platform by means of pivots 64 as shown in FIG. 2. The grindstones are carried at one end of the lever arms 62, and the other ends of the lever arms are provided with weights 66 the purpose of which is to bias or urge due to weight differential the lever arms into a position whereby a portion of the grindstones project upwardly through slots 68 provided in the surface of the platform. In the normal position or rest position of the lever arms 62 the grindstones project upwardly through the slots 68 provided and are positioned in the path of travel of the skate blades as defined by reciprocal movement of the carriage assembly. The force of contact of the grindstones with the skate blades is determined by the weight of the weights 66 and as shown in FIG. 2 the positioning of the weights on the ends of the levers may be varied by selective positioning of the weights along lever arm projections 70 to vary the pressure of the grindstones against the skate blades.
The undersurface of the platform 2 carries a single electric motor 72 which effects the to and fro reciprocal movement of the carriage and also drives the two grindstones. Rotation of the grindstones is provided by means of V-belt 74 engaging over pulley 76 which in turn is connected to two similar pulleys 78 by means of axle 80 and these two pulleys 78 are in driving connection with the grindstone pulleys 82 by means of V-belts 84. As the axes of rotation of the pulleys 82 and the axes of rotation of the pivots 64 are identical, rotation of the lever arms 62 does not change the tension in the V-belts 84.
It is preferredthat the grindstones or grinding wheels rotate in the direction shown by the arrow in FIG. 1 to maintain the carriage and clamping assembly as free of dust and particles resulting from the grinding operation.
The electric motor 72 also drives a gear reducing assembly shown generally by numeral 86 by means of V- belt 88. The gear assembly 86 then drives by means of a chain 90 and sprocket wheels 92 and 94 a drive chain 96 shown in FIGS. 2, 4a and 4b and 5.
The carriage assembly 6 is provided with a downwardly directed flange 98 as shown in FIGS. 4a, 4b and 5 and this flange projects downwardly through a longitudinal slot 100 provided in the platform as shown in FIGS. 1 and 2. Movement of the drive chain 96 results in reciprocal movement of the carriage 6 in a manner diagrammatically illustrated in FIGS. 4a, 4b and 5. The downwardly directed flange 98 is provided with a vertical slot 102 with the length of the slot 102 being somewhat greater than the diameter of the sprocket wheel 94 which drives the chain. The chain is provided with a drive pin 104 which engages within the slot 102 of the flange. As movement of the drive chain commences the drive pin 104 is carried along and as the drive pin 104 is engaged within the slot 102 of the flange 98 the carriage is moved. Movement of the carriage will now be described with reference to accompanying diagrammatic representations in FIGS. 4a, 4b and 5. In FIG. 4a movement of the chain 96 in the direction indicated by arrow A will of course result in movement of the carriage in a similar direction. In FIG. 4a the drive pin 102 is positioned upwardly in the slot 102. As the chain moves counterclockwise as shown the drive pin carried by the drive chain will pass around sprocket wheel 94 and move downwardly in the slot 102. During downwardly movement of the drive pin in the slot the forward movement (to the left in FIG. 4a) of the carriage stops. However as the pivot moves downwardly around the sprocket 94 and towards the right as shown in FIG. 5 the drive pin imparts a movement to the flange to move the carriage in the direction of arrow B in FIG. 4b. Thus the drive chain always moves in a single direction as indicated by arrows A but as the pivot pin carried by the drive chain passes around the sprockets 94 and 94 the direction of movement of the carriage reverses.
With this arrangement the carriage assembly automatically reverses in direction when it reaches the end of the track and returns to its original or rest position without the necessity of having to provide a reversing type electric motor to impart the desired reciprocal motion. A suitable microswitch operable to stop the electric motor after one reciprocal cycle of the carriage provided as shown at 106 in FIG. 2.
It will be appreciated from the above that the entire automatic or semi-automatic operation of the apparatus is provided by a single electric motor which drives the two grindstones and also effects the desired reciprocal motion to the carriage assembly. Electrical power to the motor enters the apparatus by way of conduit 108 into an electric control box 110 with output from the control box to the motor being through electric conductor 112.
In order to provide safety features to prevent injury and to ensure that the skate blades are properly positioned before commencement of operation various features including microswitches may be incorporated into the electrical circuitry of the apparatus.
These microswitches may include a microswitch 114 provided on the underside of the platform having a pushbutton projecting upwardly through the platform 2 and which is normally opened and is closed only when the closure 12 of the apparatus is in closed position. In other words this microswitch 114 with a lead 116 back to the control box 110 will prevent operation of the apparatus when the closure 12 of the device is in other than tightly closed position. In order to ensure that the clamping means are securely fastened before operation a further microswitch 118 may also be provided on the undersurface of the platform with the pushbutton of this second microswitch normally being in the open or non-conductive position. The pushbutton of this microswitch 118 is depressed by deflecting plate 54 when the clamping arm 48 is moved to clamping position, and it is only when the deflecting plate 52 depresses the pushbutton that the control box will provide electrical power to the drive motor.
With these safeguards it is of course quite apparent that operation of the apparatus is completely safe for use by any individual including children.
The electrical circuitry and operating pushbuttons shown in FIGS. 1 and 2 will now be described, but it will be appreciated that variations of the electrical circuitry and operation of the apparatus may change without departing from the scope of the present invention.
In FIG. 1 the end of the unit may be provided with an instruction panel indicated generally at 120 as well as a number of indicator lights (indicated at 121) the function of which will now be described.
When one wishes to sharpen a skate or a pair of skates the cover 12 is first opened and the skate or skates positioned in the slots provided in the carriage assembly. The clamping lever 48 is then moved to clamp the skates in position and when this is done the deflecting plate 52 closes microswitch 118 to light a lamp on the control panel to indicate that the skates are properly clamped. The cover 12 is then lowered and upon the cover contacting the pushbutton of microswitch 114 a further lamp will light on the control panel.
If the unit is coin-operated, the user will then deposit a sufficient amount of coinage and when this is done a further lamp on the control panel will light. When these lights are all lit the user is then aware that the machine is ready for operation and that by pushing a suitable operating button such as button 122 sharpening will commence.
When the user pushes the operate button 122 and all of the microswitches are closed, power is then conducted from the control box 110 via the conduit 112 to drive the electric motor 72 to rotate the two grindstones and drive the drive chain to effect movement of the carriage.
As the carriage moves from the start position as shown in FIG. 1 the downwardly facing skate blades contact the grind stones which upon contact with the skate blades move downwardly against the bias of the lever arms 48 and the grindstones follow the edge of the skate blades as the skate blades pass thereover. As the skate blades lose contact with the grindstones the weights 66 return the grindstones to their original position and as the carriage continues its forward movement the grindstones contact and wear against the dressing blocks 54 discussed above to maintain the grinding surface of the grindstones in desired configuration. As the pivot pin 104 carried by the drive chain passes around the sprocket wheel 94 the movement of the carriage is reversed and the carriage moves in the direction as indicated by arrow B in FIG. 4b. This return movement again causes the grindstones to be dressed by the dressing stones and the grindstones further sharpen the skate blades by the return movement of the skate blades. For each forward and rearward movement of the carriage assembly the skate blades are subjected to two grinding operations, and it has been found that the grinding accomplished by this forward and back movement of the carriage is sufficient to satisfactorily effect sharpening.
The axes of rotation of the grindstones are normal to the direction of travel of the skate blades with the result that the blades are sharpened longitudinally which minimizes the formation of any slight burr which may form along the edges of the skate blade as a result of the grinding. While it has been found that any slight burr so formed is removed after a few skating strokes, it may be preferable to provide the apparatus with suitable rubbing stones to remove the burr before the skates are removed from the machine.
This may be accomplished by small attachments such as shown in FIG. 6 which are positioned on the platform 2 in the path of travel of the skate blades and between the grindstones and the carriage assembly when it is in start or rest position as shown generally at 124 in FIG. 1. The positioning of the de-burring attachment is not shown in FIG. 2.
The de-burring arrangement shown in FIG. 6 consists of a plate member 126 positioned in an opening in the platform 2 and held therein by bolts 128 or the like. A hard rubber core 130 is securely fixed to the plate 126 and the shafts 132 of a pair of rotary file (or the like) members 134 are firmly embedded in the core. The file members are so positioned that passage of a skate blade (a portion thereof being shown in broken lines at 136 in FIG. 6) therebetween causes outer respective movement of the members in the direction of arrows 138 so a thorough rubbing of the sides of the blade edge is achieved to remove any slight burr.
The file members 134 may be provided with pointed teeth members with the teeth pointing in the direction of forward movement of the carriage assembly. With this arrangement the points of the teeth directly contact any burr on the skate edges during return travel of the skate blade and after final passage over the grindstones to accomplish the de-burring.
The primary function of the present apparatus as shown in FIG. 1 is to sharpen skates of the tube-type variety worn by hockey players and generally preferred by men, and not to sharpen skates of the so-called fancy-skate type which are provided with picks at the forward end of the blade. However the apparatus can be used for this latter purpose by carefully positioning the blades so that the picks are not encountered by the grindstones, or by providing the machine with suitable selection means to lower the grindstones prior to commencement of operation of the machine to avoid contact with the picks and only contact the blade edges which of course are somewhat lower than the picks.
Referring now to FIGS. 7 to 11 in detail, a further embodiment of the present invention is shown in detail in FIG. 7, wherein numeral 202 indicates various framing members and numeral 204 designates a track or upper channel member on which the wheels 206 of a trolley or carriage 207 ride. A skate, including boot,
generally indicated at 208 is clamped in the carriage by suitable means and in operation the carriage is moved reciprocally on tracks 204 by chains or conveyors 210 which pass around sprocket wheels 2112 and 214, mounted at each end of the framing. To drive the chains 210 the sprocket wheels 212 are secured to an axle 216 which extends transversely across the framing and which is driven by an electric motor 218 through a drive shaft 220, sprocket 222 and drive chain 224. A sprocket which is securely fixed to axle 216 and which is engaged by drive chain 224 is not shown in FIG. 7. The electric motor 218 is of the reversing type.
When a skate 208 is positioned and clamped in the carriage, the electric motor 218 is activated to move the carriage from the stop or rest position shown in full lines in FIG. 7, to the left as shown in FIG. 7. When the carriage has reached the extreme left hand position it contacts a microswitch 226 to reverse the electric motor to return the carriage to the position shown in FIG. 7 where the carriage contacts a second microswitch 228 to stop motor 218.
When the skate is clamped in the carriage 207 the skate blade 230 projects downwardly and during forward movement of the carriage (from right to left in FIG. 7 the skate blade is contacted and sharpened by a grinding wheel 232 which is driven by an electric motor 234 by means of drive belt 236.
The grinding wheel 232 forms part of a sharpening or grinding assembly which consists of a motor housing 238 which is pivotally suspended within the framing by a support rod 240 which is securely fixed to upright framing members 242. The grinding wheel 232 is rotatably carried by an axle 244, which is supported by two converging arms 246 which are secured to the motor housing 238 and which together form a lever arm. To counteract the weight of the grinding wheel 232 and arms 246, a counterweight 248 is provided. The weight of the counterweight is so selected to normally retain the sharpening assembly in an upper position shown in FIG. 7.
When electric motor 218 is started to move the carriage 207 forwardly, electric motor 234 is also activated to rotate the grinding wheel. Alternatively and preferably, a delay switch (not shown) may be included in the electric circuitry (not shown) to delay movement of the carriage until the grinding speed.
As the carriage moves forwardly the skate blade 230 contacts the grindstone or grinding wheel 232 which commences sharpening of the blade. As the sharpening assembly is pivotally carried by one rod 240 the grinding wheel moves downwardly on contact with the skate blade 230 to follow the longitudinal profile or contour of the skate blade 230 and to sharpen the blade along its full length.
Suitable means may be provided to regulate the pressure the grindstone or grinding wheel exerts against the skate blade during movement of the carriage, as such regulation or variation is desirable depending upon the dullness of the blade to be sharpened. One way in which this can be accomplished isto provide spring tension means in the path of movement of the motor housing to resiliently resist its pivoting action. This may be done by providing a shaft 250 carried by the framing members 252 and which is selectively rotatable by means of a hand knob 256 which is keyed to the shaft 250 and the shaft is retained in a selected position by means of a spring-loaded stop or ratchet lever 257 which engages a sprocket wheel 259. To select the desired tension the knob is pulled outwardly a short distance so that the ratchet 257 rides on a sleeve 261 and the knob and shaft rotated and then pushed back in to enable the ratchet to engage in a slot of the sprocket 259.
The spring leaves 254 may be made of spring steel and may be of different resilient strength, and by selectively positioning the hand knob 256, the leaves are so positioned to impart the desired resistance to pivotal movement of the motor housing and regulate the force with which the grinding wheel is held against the skate blade.
When the carriage reaches its left-hand position with reference to FIG. 7, the carriage activates microswitch 226 to reverse motor 218 and reverse the direction of movement of the carriage and to cause pneumatic pressure from a pneumatic compressor assembly generally indicated at 255, consisting of an electric motor 258 compressor 260 and tank 262 to activate piston 264 in pneumatic cylinder 266 to extend from the cylinder and to contact and to pivot the motor housing and 'lower the grinding wheel 232 so that the grinding wheel does not contact the skate blade during the return travel (from left to right in FIG. 7) of the carriage. In addition to this function the piston 264 lowers the grinding wheel against a spring-loaded dresser or dressing stone 268 to condition the grinding surface of the wheel.
After the carriage has returned to the position shown in FIG. 7 where it contacts microswitch 228, piston 264 is retracted into cylinder 266 to permit the motor housing to return to its normal balanced position as shown in FIG. 7 and ready for the next sharpening movement, and the electrical power supply to the various electric motors is broken.
Depending upon the condition of the skate blade one or more passes over the grinding wheel may be necessary to sharpen the blade.
The complete assembly according to FIG. 7 can also be provided with a cover 290 of suitable transparent impact resistant material closable by a piano hinge or the like 292 to enclose the complete unit during operation and which would act to serve the functions of being a sound-deadener and also a safety barrier to guard against flying filings and the insertion of hands or fingers into the mechanism.
In the operation of the embodiment shown in FIG. 7 a skate is positioned in the carriage and the cover is closed to close the cover microswitch 304 and a microswitch is closed by a proper positioning of the skate blade. The start button is then pushed to start motor 234 to rotate the grindstone. After a suitable delay to permit the grindstone to reach operating speed, a suitable delay mechanism then activates motor 218 to start the carriage in its forward travel during which the skate blade is contacted and sharpened and honed by the grindstone as described above. When the carriage contacts microswitch 226 the motor 218 is reversed to return the carriage to the start position and at the same time activates pressure assembly 255 to supply pneumatic pressure to cylinder 266 to move piston 264 outwardly toward the motor housing 238 which it contacts and pivots to lower the grindstone from the path of travel of the skate blade during the return travel of the carriage, and against the trimmer or dresser 268 to dress the surface of the grindstone. When the carriage reaches its original position microswitch 228 is contacted to stop motor 218 and release the pressure from the cylinder 266 to permit withdrawal (by suitable means such as spring action not shown in the drawings) of the piston 264 into the cylinder and enable the grinding assembly to pivot to its normal position as shown in FIG. 7. The assembly is then ready for another pass over the grindstone, if such is thought to be necessary, by simply pressing the start button, or alternatively the cover is simply opened and the skate removed.
Variations of the inventive concept could involve the positioning of a disposable dust or filing-catching bag within the apparatus to catch filings and grindings, and additionally a vacuum system and disposable filter bags could be incorporated within the assembly to maintain the unit in a state of cleanliness.
When sharpening a pair of skates it is of course necessary to provide two grinding wheels and each grinding wheel is carried by an individual grinding or sharpening assembly, such as that shown in plan view in FIG. 8. Each of the assemblies shown in FIG. 8 are provided with their own electric drive motors; and of course each wheel will be provided with an individual dresser 268 (not shown in FIG. 8) as is shown in FIG. 7. Additionally, each of the sharpening assemblies shown in FIG. 8 will be provided with individual means to lower the grinding wheel out of contact with its respective skate blade during the return travel of the carriage. In FIG. 8, one of the sharpening assemblies is provided with reference numerals identical with that of FIG. 7, whereas the other sharpening assembly is provided with identical numbering but which has been primed.
A variation of a clamping mechanism sutiable for installation in the carriage is illustrated in plan view in FIG. 9 and in end view in FIG. 10 which is a view taken generally along line BB of FIG. 9.
In FIGS. 9 and 10, a trolley 207 is shown having lower slots 269 and 269 through which the blades of skates which are to be sharpened project when the skates are clamped in position. In FIG. 9, the top portion of the trolley 207 has been removed for a better understanding but the openings provided in the top surface of the trolley 207 and which receive the skates which are to be sharpened are indicated at 312 and 312 as shown in broken lines.
The clamping assembly of FIGS. 9 and 10 consist of two stationary clamping sections 314 and 314 which are provided with inwardly projecting flanges 316 and 316' respectively to engage the blade of the skate and also with resilient beads 318 and 318' which engage the conical portion 310 of a tube skate.
Two reciprocal and laterally moving clamping members 320 and 320' are slideably carried by guides 322 and 322' and are reciprocally movable with respect to their stationary clamping members in the directions indicated by the double-ended arrows 324 and 324 as shown in FIGS. 9 and 10.
A worm is rotatably carried by supports 326 and 328 which are fixedly secured to the bottom surface of the carriage and one end of the worm carries a gear 330 which is in meshing engagement with a gear 332 which is affixed to the drive shaft 334 of an electric motor 336. In FIGS. 9 and 10, the worm is indicated by numeral 338.
A worm sleeve or follower 340 surrounds the worm 338 and the worm follower is fixedly secured to a member 342 which is provided with outwardly directed flanges 344. The movable clamping members 320 and 320' are provided with inwardly directed flanges 346 and 346 which are pivotally secured to the flanges 344 by linkage members 348 and 348. It will be appreciated that rotation of worm 338 will cause movement of the worm follower 340 and the member 342 in either of the two directions indicated by the double-ended arrow 350 in FIG. 9 depending upon the direction of rotation of the worm 338. In FIG. 9 and FIG. 10, the clamping assembly is shown in open or skate-receiving position and it will be appreciated that when one or two skates are positioned in the assembly, and the electric motor 336 is activated to rotate worm 338 that downward movement of member 342 (as shown in FIG. 9) will result in the linking members 348 and 348 moving the movable clamping members 320 and 320' outwardly toward the stationary clamping members 314 and 314' respectively. The movable clamping members 320 and 320 are provided with outwardly directed clamping flanges 352 and 352 and outwardly movement of the clamping members will move the flanges 352 and 352' toward the stationary flanges 316 and 316' to clamp a skate blade therebetween. The members 320 and 320' are also preferably provided with resilient beads 354 and 354 to engage against the vertical conical portion 310 of a skate assembly.
In FIGS. 9 and 10, an electric motor 336 is shown for ease of clamping operation, but it will be appreciated that substitution of a geared hand wheel arrangement so that the clamping may be effected manually is possible without departing from the scope of the present invention. Moreover, while provision for receiving two skates is shown in FIGS. 9 and 10, it will also be appreciated that a single skate assembly utilizing the component parts shown in these drawings is also possible and within the framework of the invention.
FIGS. 1 1 and 12 relate to a variation for the lowering of the grinding wheel or grinding wheel assemblies during return movement of the carriage to its rest position. As will be appreciated from these drawings and from FIG. 7, the chain or conveyor 210 moves within a track or channel 204 and the wheel 206 of the carriage 207 also ride in this channel 204. The lowermost portion of the endless chains are carried in a lower channel 204 as seen in FIG. 9. In this embodiment, a portion of the lowermost channel 204 is cut away to receive one arm 355 of a dog-legged or bell-crank lever which is indicated generally at 356, and the bell-crank lever also is provided with a second arm 358. A shaft 360 is provided on the lever 356 with this shaft being pivotally received within a bearing member 362 and secured to the underside of the channel 204. The arm 358 pivotally receives the end of a rod 364 which extends transversely across the machine and normal to the direction of travel of the carriage 207 with the rod 364 being positioned above the arms 346 of a sharpening assembly. The arm 354 is provided with a chain-engaging tap 366 which is mounted by means of spring 368 to enable the tap to move in the direction indicated by arrow 370 for reasons that will be discussed below.
During the forward motion of the carriage 207, the upper portion of the chain 210 will move in the direction of arrow 372 as shown in FIG. 11, with the lower most portion of the chain 210 moving in the direction of arrow 374. The lowermost portion of chain 210 will, during movement in the direction of arrow 374, pass over the end of cap 366 to maintain rod 364 in an uppermost position. However, once the carriage 207 begins its return travel, the direction of travel of the upper and lower portions of the chain 210 become reversed with the lower portion of the chain 210 then moving in a direction indicated by arrow 376. As chain 210 begins to move in this latter direction, the end of cap 366 engages within a chain link and this engagement causes pivotting of the bell-crank arm assembly in the direction of arrow 378 which lowers the rod 364 against the arms of the sharpening assembly to pivot the sharpening assembly on rod 240 to lower the grinding stone 232 to a position out of the path of travel of the skate blade during the return movement of the carriage. When cap 366 is engaged in a chain link, the cap is compressed against the force of spring 368 to prevent binding or malfunctioning of this assembly. Once chain 210 moves a sufficient distance so that the end of cap 366 becomes withdrawn from the link with which it became initially engaged, the movement of the chain over the cap 366 will of course maintain the rod 364 in lowered position. The rod 364 will remain in lowered position when the carriage is in its rest position but as soon as the carriage begins moving in its forward direction, the action of the lower portion of chain 210 on cap 366 will again pivot the lever assembly 356 and permit the sharpening assembly to pivot to its skate sharpening position.
In FIG. 7, the pivotting of the skate sharpening assembly to a position out of its path of travel of the skate blade during the return movement of the carriage is illustrated, and in FIGS. 11 and 12, a second embodiment for pivotting the sharpening assembly is indicated. Of course, other pivotting embodiments could be usefully employed and one such arrangement could be an electromagnet positioned below the arms 246 of the sharpening assembly which would be activated when the carriage touched microswitch 226 to lower the grincistone 232 from the path of travel of the skate blade.
Utilizing an electromagnet assembly as discussed above or the mechanical assembly shown in FIGS. 11 and 12 and also utilizing a clamping mechanism such as shown in FIGS. 9 and 10 remove the necessity of providing a pneumatic air source, and in a preferred construction of the skate sharpening apparatus, electrical components only are used and it is then not necessary to provide the pressure asembly 255 as shown in FIG. 1.
If the clamping assembly shown in FIGS. 9 and 10 were to employ a simple hand tightening arrangement rather than an electric motor and the sharpening assembly was lowered by mechanism such as shown in FIGS. 11 and 12, or by electromagnetic means, then the only motors required for a successful operation of the apparatus would be electric motor 218 and the necessary electric motors 234 (234) to drive the grinding wheel 232. With such a construction the cost of the present apparatus can be kept to a minimum.
The operation of the preferred construction of the apparatus according to FIG. 7 is as follows:
The cover 290 is first lifted to provide access to the carriage 207 and a (or two) skate(s) which is (are) to be sharpened, is (are) suitably positioned in the carriage and clamped therein and if skate contacting microswitches are provided, the positioning of the skates will close these microswitches. The cover 290 is then closed depressing microswitch 204 to complete the position through a path of travel over and above the grinding or sharpening assembly whereby the grinding wheel 232 sharpen the skate blade as discussed above. When the forward movement of the carriage is completed, the carriage contacts microswitch 226 to reverse motor 218 to return the carriage to its rest po sition. The sharpening arrangement may be maintained in a lowered position and in contact with the dressing assembly 268 by any of the suitable means indicated above and if such means are electromagnetic the contacting of microswitch 226 by the carriage 207 could activate the electromagnetic assembly. The carriage 207 then returns to its rest position where it contacts microswitch 228 which is the completion of one sharpening cycle. As indicated above, one, two or more sharpening cycles may be programmed into the electrical circuitry of the apparatus. The cover 290 is then lifted and the sharpened skates are removed from the carriage by means indicated above and the carriage is then ready to receive the next skate or pair of skates to be sharpened. If a coin-operated mechanism is included in the circuitry of the apparatus, the depositing of a suitable coin in the mechanism will be necessary before the machine circuitry may be completed and a sharpening cycle commenced.
In the foregoing disclosure the use of a reversing type electric motor 218, and microswitches 226 and 228 are discussed. It will be appreciated however that a single direction electric motor could be used in place of motor 218 and that reversal of the direction of travel of the carriage could be accomplished by purely mechanical means. This could be accomplished by replacing the microswitches 226 and 228 by mechanical levers which when contacted by the carriage (or a portion of the chain) to act on friction clutches to reverse the direction of travel of the chain 210 and the carriage 207. The electric motor would drive a shaft on which are rotatably mounted a pair of bevelled gears which are both in meshing engagement with a common bevelled gear to which is attached a drive pulley to drive axle 216. The shaft would be reciprocally mounted and would carry two friction clutches so that movement of the shaft in one direction would cause one of the clutches to contact one of the pair of bevelled gears to rotate the common bevelled gear in one direction and move the carriage in a first direction, whereas movement of the shaft in the other direction would cause the other of the clutches to contact the other of the pair of bevelled gears to rotate the common bevelled gear in the other direction to move the carriage in an opposite direction. Such an assembly will be readily apparent to those skilled in the art and further description is not believed necessary here.
Additionally, the assembly shown in FIGS. 1 and 7 consists of a lower metal panelled section, and an upper cover made of plastic or acrylic or other suitable transparent plastic material. It will be appreciated however that the cover could be made of materials other than transparent material shown such as metal or the like.
FIG. 1 shows a platform 2 but it will be clear that the platform could be completely omitted if desired and suitable provisions made to support and pivot the two grindstones and to provide proper support for the track member 4.
While it has been found that the two dressing stones employed do not generally require any cleaning during use the unit can if desired by provided with wire brush means or the like suitably carried by the platform (shown in FIG. 1) to engage and rub against the dressing stones during movement of the carriage to ensure that the stones are maintained free of any clogging material such as any grinding particles.
1. Ice skate sharpening apparatus comprising:
a. a frame supporting an upper, horizontal and longitudinal track;
b. a carriage mounted for straight line reciprocation on said track;
0. clamp means on said carriage to receive and secure at least one ice skate blade so that its ice engaging edge faces downwardly and is alligned parallel to the line of reciprocation of said carriage;
d. a transverse mounting shaft fixed to the frame below the track and normal to the line of reciprocation of the carriage;
e. at least one arm pivotally mounted on the shaft and lying in a plane parallel to the line of reciprocation of the carriage;
f. a rotatable disc-shaped grinding element having a convex edge carried by one end of the arm, the disc-shaped grinding element lying in the plane containing the line of reciprocation of the skate blade;
g. adjustable counter-weight means carried by the other end of the arm causing the arm to rotate about the mounting shaft to bring the convex edge of the grinding element into gravity biased contact with the skate blade;
h. electric motor means to drive the carriage from a starting position at one end of the track to a position at the other end of the track and to return it to the starting position, thereby causing the skate blade to traverse the grinding wheel clement;
i. said electric motor also rotating the grinding element at the same time;
j. means associated with the means to drive the carriage operable to pivot the arm carrying the grinding element so as to lower the grinding element out of engagement with the skate blade while the carriage is returning from its position at the other end of the track to tis starting position, and
k. grinding element dressing means positioned to be engaged by the rotating grinding element during movement of the carriage from its position at the said other end of the track to its starting position to maintain the desired convex configuration of the edge of the grinding element.
2. Ice skate sharpening apparatus as claimed in claim 1 wherein the clamp means are capable of receiving and securing a pair of ice skate blades in parallel, side by side relationship and wherein the traverse mounting shaft carries a pair of arms independently pivotable thereon, each arm carrying a disc-shaped grinding element at one end and counter-weight means at the other end, each grinding element lying in the plane of one of the skate blades.