Abstract:
An ice resurfacing machine for small and medium-size indoor and outdoor ice skating rinks comprises a light towing vehicle, a resurfacing attachment, and a lifting and leveling assembly connecting them. To eliminate ruts in the ice, the machine removes only a thin layer of ice by scraping, fills the ruts with “snow” created by the scraping, skating, and precipitation, and adds water to fill the rut. The cold from the base ice and/or the atmosphere freezes the water and thus eliminates the rut. The machine may also be used to remove heavy snow or reduce the thickness of the ice.

Description:
CROSS REFERENCE TO RELATED APPLICATION  
       [0001]     This application discloses and claims subject matter which was disclosed in copending provisional patent application Ser. No. 60/552,820, filed Mar. 12, 2004. 
     
    
     FIELD OF THE INVENTION  
       [0002]     This invention relates to a system for resurfacing ice skating rinks.  
       BACKGROUND OF THE INVENTION  
       [0003]     Ice skating is extremely popular in the northern states of America and is growing increasingly popular in the southern states. The demands for ice skating surfaces are becoming nearly impossible to meet. Many ice rinks have to operate 24 hours a day to meet skaters&#39; needs. The number and availability of ice skating rinks are limited by the maintenance required to keep the quality of the ice surface in an optimum or at least satisfactory condition. Such maintenance involves eliminating ruts and the like created by the skaters, removing the resulting ice particles, removing any fallen snow accumulation (in the case of an outdoor rink), and controlling the thickness of the ice.  
         [0004]     It is important to control the thickness of the ice. The average ice thickness on an indoor ice skating rink is about 0.75 to 1.0 inch. If, for example, a person were merely to constantly shovel away the ice powder created after an ice skating session and reapply water, the ice would eventually become too thick for the ice chillers to handle and the ice would become soft and wet.  
         [0005]     Backyard or homemade ice rinks, ponds, and lakes are called natural ice skating surfaces. They are usually created outdoors when the temperature is constantly below 25° F. Natural ice skating surfaces rely on cold air temperatures to keep the surface frozen. Even in colder climates, ice skating surfaces cannot have thick ice because they are hard to keep frozen. Natural ice skating surfaces also have the disadvantage of not having protection from snowfall.  
         [0006]     Typically these smaller rinks are maintained manually, by one or more persons using hand tools, such as a shovel, a wheelbarrow, a hose, and a T-shaped squeegee-like implement. This not only tends to be burdensome, labor intensive, energy-depleting, and slow, but it also may produce an uneven, unduly thick, and/or poor quality surface. As a practical matter, the long term result of these deficiencies is likely to be that the ice surface is resurfaced with insufficient frequency. Manual maintenance also requires fairly large quantities of water, and sometimes creates fog which can be a problem in enclosed rinks. As a member of a neighborhood recreation association having a 7,000 sq. ft. indoor ice skating rink, I have had personal experience in hand shoveling and resurfacing and the attending disadvantages thereof. That experience led to the present invention.  
         [0007]     Large ice resurfacing machines such as those sold under the trademark Zamboni® or Olympia® have been used for many years for large rinks, for example regulation hockey rinks having regulation dimensions of 200 ft.×85 ft. and other rinks having an area of 19,000 to 20,000 sq. ft. These large machines are excellent for large rinks, but their initial expense, size, complexity, training, maintenance, and storage requirements render them less suitable for medium and small size rinks, such as those operated by homeowners, municipalities, recreation associations, parks, private establishments, and the like. Currently such machines of one manufacturer have a selling price in the lower $70,000 range and weigh in excess of 9,000 pounds. Also, their size limits their turning radius and maneuverability and often requires a separate building for storage. In addition, they are complex, requiring considerable skilled maintenance and operator training. Certification of an operator of one of these machines requires that he or she attend a 3-day training course. More recently, downsized versions of these machines such as the Zamboni® Model 100 and the Olympia 250® have become available, but aside from their size and weight these have many of the same shortcomings.  
         [0008]     The Zamboni® and Olympia® and various other machines shave off a surface ice layer of a sufficient depth, which can be as much as ⅛ inch, to remove substantially all of the ruts, and then deposit water on the resulting rut-free substrate so as to create an entirely new layer of fresh ice on the substrate. The shaving produces a rather large quantity of ice particles or “snow”, which is carried away by conveyors in the machine, stored in a snow box in the machine, and later disposed of as waste.  
         [0009]     There has been a long-felt but unmet need for an ice resurfacing machine which has the following attributes and capabilities: relatively low initial cost; compact; easily maneuverable; short turning radius; easy to maintain and repair with standard parts; operator friendly; minimum water requirements; minimum snow disposal requirements; fast; adjustable; flexible, with ice thickness reduction capability and heavy snow removal capability; providing high quality ice surfaces; suitable for ice skating rinks of any size, including small and medium size rinks; and suitable for both indoor and outdoor use.  
       BRIEF SUMMARY OF THE INVENTION  
       [0010]     An object of the invention is to fill the above-identified need, or at least provide as many of the attributes and capabilities as possible, bearing in mind the compromises necessary to reconcile the inherent competition between them.  
         [0011]     Rather than remove a layer of ice that is sufficiently thick to remove substantially all of the ruts and then replace it with water, the present invention removes only a thin layer of ice, leaves the ruts, fills the ruts with snow, and adds hot water to fill the interstices in the snow in the ruts and melt that snow. This leaves the ruts completely filled with water, which when frozen will provide a smooth ice surface and effectively eliminate the ruts.  
         [0012]     The inventive approach eliminates the need for apparatus to convey large quantities of snow off the ice and into the resurfacing machine, to store it in the machine, and to haul it away. This greatly reduces the cost, size, weight, and complexity of the machine. It also conserves water. Also, the inventive machine has the capabilities of removing heavy snow and reducing ice thickness. In addition, it is easy to operate and maintain and produces an excellent ice surface. Further, it works sufficiently fast to be useful for larger rinks as well as small and medium-size rinks.  
         [0013]     Apparatus utilizing this approach takes advantage of and enhances these and other aspects and advantages of the invention, including an integrated combination of a light towing vehicle, a compact resurfacing attachment, and a lifting and leveling assembly connecting the vehicle and the attachment.  
         [0014]     Sales data for ice resurfacing machines according to the present invention are consistent with my belief that the invention fills a long-felt need. My company, Ragged Point Industries, sells these machines under the trademark “The Ice Wizard”. The first sale took place on Sep. 27, 2004. In the less than 6 months since then, we have sold 22 of these ice resurfacing machines, in the United States and abroad. One of these machines is being used at the ice skating rink on the Eiffel Tower in Paris. Four of them are being used at ice rinks in Saudi Arabia, and another one is being shipped to Saudi Arabia. Ours is not a large or sophisticated operation, as all of these machines were assembled by my partner and me at my personal residence, when we were (as we still are) employed full-time in our “day jobs”. 
     
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING  
       [0015]      FIG. 1  is a right side elevation view of an ice resurfacing machine according to the invention, resting on an ice surface.  
         [0016]      FIG. 2  is side section view of the resurfacing attachment shown in  FIG. 1 , showing a portion of the lifting and leveling assembly.  
         [0017]      FIG. 3  is a plan view of the resurfacing attachment shown in  FIGS. 1 and 2 , with the water spreader towel removed.  
         [0018]      FIG. 4  is a rear view of the resurfacing attachment shown in  FIGS. 1-3 .  
         [0019]      FIG. 5  is a view similar to  FIG. 2 , but showing the invention being used in resurfacing ice.  
         [0020]      FIG. 6  is a plan view of a turn groove in an ice surface.  
         [0021]      FIG. 7  is a section taken at  7 - 7  in  FIG. 6 , with the groove filled with snow.  
         [0022]      FIG. 8  is a plan view of a slip or stop gouge in an ice surface.  
         [0023]      FIG. 9  is a section taken at  9 - 9  in  FIG. 8 , with the gouge filled with snow.  
         [0024]      FIG. 10  is a plan view of a toe pick hole in an ice surface.  
         [0025]      FIG. 11  is a section taken at  11 - 11  in  FIG. 10 , with the hole filled with snow. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
     Definitions  
       [0026]     The following terms are used throughout this application in accordance with these definitions, unless a different interpretation is required by the context.  
         [0027]     The terms “ice rink” and “rink” refer to ice having a horizontal surface used for ice skating, including recreational, professional, hockey, or figure skating, whether located indoors or outdoors, constructed or naturally occurring (such as a pond), or cooled naturally or by refrigeration.  
         [0028]     The term “rut” refers to local, concave imperfections in the surface of an ice rink, including grooves, nicks, cracks, and gouges. (Ruts are typically caused by ice skate blades, falls, and hockey sticks.)  
         [0029]     The term “snow” refers to particles of frozen water removed from the surface of an ice rink by scraping, including scrapings of the top layer of the ice, skater-generated snow, fallen snow, sleet, frozen rain, condensation, or other precipitation on the surface, including any liquid water mixed with them. Since “snow” includes associated liquid water, its nature will vary greatly depending upon wetness, compaction, temperature, slushiness, particle size, flowability, stickiness, etc.  
         [0030]     The term “average thickness”, in a reference to a layer of snow being removed by a scraper blade from an ice surface, means the theoretical thickness the layer would have if the surface were perfectly and uniformly flat and level.  
         [0031]     The term “box” is used in accordance with its dictionary definition relating to machines, e.g., an enclosing casing or part in a machine.  
         [0032]     The term “cut”, used as a noun, means a series of passes of the machine, usually overlapping, that cover a desired rink area, as one would use that term with respect to mowing a lawn or field.  
       The Ice Resurfacing Machine  
       [0033]      FIG. 1  shows an ice resurfacing machine according to the present invention resting on ice surface  10 . The machine consists of four groups of components—vehicle  12 , resurfacing attachment  14 , lifting and leveling assembly  16  connecting them, and water supply system  17 .  
         [0034]     Vehicle  12  has wheels  18 , steering mechanism  20 , driver&#39;s seat  22 , a motor (not shown), a battery (not shown), and a standard trailer hitch receiver  24 . The particular vehicle shown is a golf cart with an electric motor. Other vehicles, such as all-terrain vehicles and tractors, may be used for outdoor rinks. As an alternative to battery power, motors powered by compressed gas such as butane or propane may be used for indoor rinks.  
         [0035]     Water supply system  17  consists of water supply tank  26  in vehicle  12  behind driver&#39;s seat  22 . Located within tank  26  is water pump  27 , which is connected to water supply line  28  via water regulator  29 , which may be manually regulated to vary the volume of water flow. Water regulator  29  is a ball valve. Alternatively, water supply system  17  may be mounted on resurfacing attachment  14 .  
         [0036]     As shown in  FIGS. 2, 3 , and  4  as well as in  FIG. 1 , resurfacing attachment  14  includes snow box  30 , which is open at the bottom and enclosed on the remaining five sides. It may be called either a “snow box”, because of its function of generating, using, and collecting “snow”, or an “ice box”, because of its location and end product. It is made of sheet metal, but other materials such as plastic compositions may also be used. Attached to the top wall of snow box  30  is support frame  32 , which consists of welded vertical, lateral, and longitudinal square metal tubes.  
         [0037]     Ice blade mounting bar  34 , which is shown in  FIG. 2 , extends laterally across the width of box  30  and is fastened to the side walls of box  30 . Ice blade  36 , which is made of tempered steel, is bolted to mounting bar  34  by two bolts in longitudinal slots in blade  36 . The slots are parallel to the longitudinal axis of the vehicle. Mounting bar  34  and blade  36  are inclined at an angle of 12° to the surface of the ice. By loosening the bolts, sliding blade  36  in the slots forward or backward to a new position, and re-tightening the bolts, the height of the sharp cutting edge of the blade with respect to the bottom edges of the box may be varied. It is not possible, or necessary, to vary the height of the blade during resurfacing. Usually the edge of blade  36  will be coplanar with the bottom edges of box  30 . For a dry cut to reduce ice thickness, the blade edge will extend below the box edges by ⅛ inch or so. The slots are sufficiently long to allow the blade edge to protrude ¼ inch below the box edges.  
         [0038]     Water distributor  38  is a tube secured to the rear wall of snow box  30  by hangers  40 . A number of aligned holes  42  spaced V 2  inch apart in the tube are aimed at the rear wall of box  30 . One end of water distributor  38  is connected to water supply line  28  at a 90° elbow.  
         [0039]     Also attached to the rear wall of snow box  30  is towel holder  43 . Removably connected by studs to towel holder  43  are water spreader towel  44  and towel backing bar  46 , which in turn are attached to each other. This connection enables the towel and backing bar to be quickly replaced so that the towel can be allowed to dry. Spreader towel  44  is made of terry cloth, while backing bar  46  is made of stainless steel. Towel  44  lies on the ice over the width of box  30 . A spreader towel is sometimes referred to as a “mat”.  
         [0040]     Lifting and leveling assembly  16  includes at its front end a drawbar (not shown) which engages and is removably connected to hitch receiver  24 . Post  52  is fixed to the drawbar. Pivotally connected to post  52  are central support arm  54  and two lever links  56 , which in turn are pivotally connected at their rear ends to outer support arms  60  and farther forward to the piston of hydraulic unit  58  comprising a cylinder, piston, motor, pump, and fluid reservoir. Two support bars  62  are pivotally connected at their front ends to the drawbar, at their rear ends to snow box support frame  32 , and in between to the lower ends of outer support arms  60 . By virtue of their threaded parts, the three support arms  54 ,  60  are manually adjustable, and may be lengthened or shortened in turnbuckle fashion. The lifting and leveling assembly is a three point hitch, which was commercially available before the present invention was conceived.  
         [0041]     Adjustment of support arm  54  levels the lower edges of snow box  30  from front to rear. Adjustment of support arms  60  levels the lower edges of the snow box  30  from side to side. Actuating hydraulic unit  58  to extend the piston lifts snow box  30  vertically, while actuating it to retract the piston lowers snow box  30  so that it rests on the surface of the ice.  
       Operation of the Ice Resurfacing Machine  
       [0042]     The resurfacing machine may be used in three different modes—routine resurfacing mode, heavy snow removal mode, and ice thickness reduction mode. Routine resurfacing, the mode of its most frequent use, is appropriate after skaters have created snow and there has been no significant precipitation, extreme wear, or degradation. Heavy snow removal is appropriate when precipitation has fallen on an outdoor rink. Ice thickness reduction is appropriate when the thickness of the ice has become or is becoming thicker than 1 inch. It will be understood that other factors may be involved (for example, heavy snow resulting from especially vigorous skating, or falling and freezing condensation from the roof of an indoor rink) and that there is no bright line between the conditions warranting the selection of the appropriate mode. Usually, when either of the latter two modes is used, the operation will be immediately followed by a routine surfacing.  
         [0043]     The heavy snow removal and ice thickness reduction modes are used without applying water to the surface of the ice and hence are sometimes referred to as a “dry cut”. Towel  44  is removed for either of these modes. In the routine resurfacing mode, blade  36  is adjusted and secured so that it is coplanar with the bottom edges of box  30 . In the heavy snow removal mode, blade  36  is either at that coplanar position or is adjusted and secured so that it is above the coplanar position. In the ice thickness reduction mode, blade  36  is adjusted and secured so that it is below the coplanar position.  
         [0044]     The routine resurfacing mode is carried out as follows. The operator fills tank  26  with hot water having a temperature in the range of from about 95° F. to about 120° F. and, with the box in the raised position, drives vehicle  12  to the desired starting position on the ice. Then he or she lowers box  30  until it rests evenly on the surface of the ice, turns on pump  27 , and drives around the ice in a desired pattern. Typically the pattern is a series of slightly overlapped ovals with ever-decreasing radii, possibly with an initial swath along the longitudinal axis of the rink to avoid ending with irregularities due to turning radius limitations. If the box fills completely with snow, the operator drives to a location either on the ice or on a smooth, level surface contiguous with the ice, stops the vehicle, and raises box  30 , leaving the snow exposed on the surface, so that the “dumped” snow may be shoveled into a container such as cart, either then or later.  
         [0045]     As so used in the routine resurfacing mode, the ice resurfacing machine depicted in the drawings will resurface about 8,000 sq. feet before box  30  fills up with snow to the extent that dumping is required. As used in either of the waterless modes, the box fills up more quickly and more frequent dumping is required. Also, the lower the position of blade  36 , the more snow is collected and the more frequently dumping is required.  
         [0046]     Whenever the machine is stopped on the ice, water pump  27  should be turned off and box  30  should be raised. Otherwise, the hot water will melt the ice and the towel or box will stick to the ice. This is accomplished manually by “Water On/Water Off” and “Snow Box Up/Snow Box Down” controls in vehicle  12 .  
         [0047]     In the routine resurfacing mode, with the edge of blade  36  coplanar with the bottom edge of box  30 , blade  36  will lightly scrape the surface of the ice and remove the snow already on the surface of the ice and a very thin layer of the ice. I estimate that the average thickness of this layer is about 1/32 inch, and certainly less than 1/16 inch. Blade  36  also levels the ice by removing high spots and bumps.  
         [0048]     If necessary to generate sufficient snow to fill the ruts in the surface of the ice, blade  36  may be lowered slightly. The blade may be effectively lowered in a small increment by stopping vehicle  12  and adjusting central support arm  60  so as to lower the front of box  30 , which avoids the need to move blade  36  with respect to blade mounting bar  34  as described above.  
         [0049]     During routine resurfacing, the operator manually controls water regulator  29  to adjust water flow as desired. Increased flow is warranted by higher vehicle speed, resurfaced areas that appear to have insufficient water, creating new ice at the beginning of the skating season, and building up low spots. Decreased flow is warranted by reduced vehicle speed (as may be necessary for turning corners) and standing water. The slower the vehicle speed, the better the quality of the ice resurfaced.  
         [0050]     The ice resurfacing machine according to the invention requires very little maintenance. The operator needs to make sure the batteries have the proper charge and water levels. Most golf carts require a monthly water fill. The scraper blade, though it holds a good edge and is very durable, requires sharpening from time to time. Also, the individual components are relatively light and can be easily moved and handled by one or two people.  
       The Ice Resurfacing Method  
       [0051]      FIG. 5  shows resurfacing attachment  14  being used to resurface ice in the routine resurfacing mode, as it is being towed toward the right. Blade  36  is scraping ice surface  10  so as to create snow  64 , most of which passes over blade  36  and proceeds to the rear of box  30 . The snow is collected at  66  in the buildup just ahead of blade  36  and at  67  at the rear of box  30 .  
         [0052]     Meanwhile, water pump  27  pumps pressurized hot water from tank  26 , through line  28 , and into water distributor  38 . Pressurized water issuing from holes  42  in distributor  38  strikes the rear wall of box  30  and flows down its surface due to gravity and surface tension, as shown symbolically at  68 , thereby further distributing the water in the transverse direction as it falls onto ice surface  10 . Finally, towel  44  spreads the water uniformly across the surface of the ice, where it will freeze to form good ice, typically within a few minutes.  
         [0053]      FIGS. 6 through 11  show three types of ruts commonly made in the ice by skaters.  FIGS. 6 and 7  show turn groove  80 , which has a maximum depth of  80 D.  FIGS. 8 and 9  show slip or stop gouge  82 , which has a maximum depth of  82 D.  FIGS. 10 and 11  show toe pick hole  84 , which has a maximum depth of  84 D.  FIGS. 7, 9 , and  11  show these ruts filled with snow, as will be explained next. Normally depths  80 D and  84 D are greater than 1/16 inch, but they sometimes go as deep as 1 inch (i.e., all the way through the ice). Normally depth  82 D is less than 1/16 inch. Thus, the suffix “D” refers to the maximum depth of each of these ruts.  
         [0054]      FIG. 5  depicts six ruts in the surface exaggeratedly at  70 ,  72 ,  74 ,  76 ,  78 ,  79 , going from right to left. These ruts are in different locations with respect to box  30 , blade  36 , and towel  44 , but will be used here to illustrate the sequence of the inventive resurfacing method for a single rut. Rut  70  is empty, and rut  72  is empty or nearly so. Rut  74  is partly or complete filled by collected snow from  66 . Rut  76  differs from rut  74  in that its depth has been slightly reduced because a thin layer has been scraped off the surface of the ice by blade  36 . Rut  78  has been filled, or topped off, by collected snow from  67 . Such snow is shown in  FIGS. 7, 9 , and  11  at  86 ,  88 ,  90 . Finally, rut  79  is filled with water, since the hot water filled the interstices of and melted the snow that had filled the rut.  
       Specific Data  
       [0055]     Specific data for the resurfacing machine shown in the drawings are as follows:  
                                       Dimensions   121 in. long × 48 in. wide × 54 in.           high       Weight   950 pounds       Top speed   12 mph       Capacity of water tank 26   25 gallons       Capacity of water pump 27   750 gallons per hour       Exterior dimensions of snow box 30   48 in. wide × 24 in. long × 10 in.           high       Approximate time for routine   10 minutes or less       resurfacing of 7,000 sq. ft. ice       skating rink                  
 
       Reference Character Table  
       [0056]     The following table lists the reference characters and names of features and elements used herein, with asterisks indicating groups of features and elements:  
                                           Ref.       Paragraph           Char.   Feature or element   introduced in   FIGS. shown in                   10   ice surface   0027   1, 2, 5, 6-11       12   vehicle*   0027, 0028   1       14   resurfacing attachment*   0027, 0030   1, 2-5       16   lifting and leveling   0027, 0034   1           assembly*       17   water supply system*   0027, 0029   1       18   wheels   0028   1       20   steering mechanism   0028   1       22   driver&#39;s seat   0028   1       —   battery (not shown)   0028   —       —   motor (not shown)   0028   —       24   standard hitch receiver   0028   1       26   water supply tank   0029   11       27   water pump   0029   1       28   water supply line   0029   1-3       29   water regulator   0029   1       30   snow box or ice box   0030   1-5       32   snow box support frame   0030   1-5       34   blade mounting bar   0031   2       36   ice blade   0031   1, 2, 5       38   water distributor   0032   1-5       40   hangers   0032   2-4       42   holes   0032   3       43   towel holder   0033   1, 2, 3       44   water spreader towel   0033   1, 2, 4, 5       46   towel backing bar   0033   2       —   drawbar (not shown)   0034   —       52   post   0034   1       54   central support arm   0034   1           (adjustable)       56   lever links   0034   1       58   hydraulic unit   0034   1       60   outer support arms   0034   1           (adjustable)       62   support bars   0034   1       64   snow   0045   5       66   collected snow toward   0045   5           front of box       67   collected snow toward   0045   5           rear of box       68   water   0048   5       70   rut ahead of box front   0048   5           wall       72   rut just behind box front   0048   5           wall       74   rut beneath collected   0048   5           snow at 66       76   rut behind blade   0048   5       78   rut beneath collected   0048   5           snow at 67       79   rut behind towel   0048   5       80   turn groove   0047   6, 7       80D   maximum depth of turn   0047   7           groove       82   slip or stop gouge   0047   8, 9       82D   maximum depth of slip   0047   9           or stop gouge       84   toe pick hole   0047   10, 11       84D   maximum depth of toe   0047   11           pick hole       86   snow filling turn groove   0047   7       88   snow filling slip or stop   0047   9           gouge       90   snow filling toe pick   0047   11           hole                  
 
         [0057]     It will be understood that, while presently preferred embodiments of the invention have been illustrated and described, the invention is not limited thereto, but may be otherwise variously embodied within the scope of the following claims. It will also be understood that the method claims are not intended to be limited to the particular sequence in which the method steps are listed therein, unless specifically stated therein or required by description set forth in the steps.