SPEED AND DISTANCE CALCULATOR FOR SKIS

Abstract: A speed and distance calculator for skis having a housing (1, 2) detachably secured to a ski (14) and having a rotatable wheel (17) journaled on the housing. Two magnets (19) carried by the wheel (17) interact upon rotation of the wheel with a sensor (20) to send a signal to a microcomputer (21) correlated to the number of revolutions of the wheel in unit time. The output of the microcomputer is shown in a visual display (7).

Description: SPEED AND DISTANCE CALCULATOR FOR SKIS BACKGROUND OF THE INVENT ION 1. Field of the Invention This invention relates to speed detecting devices, and particularly such a device applicable to skis. 2. Description of the Prior Art ; With reference to the classification of art as established in the United States Patent and Trademark Office the present invention is believed found in the general Class 73 entitled, "Measurement and Testing", and more specifically in subclass 490. A search in this field has revealed the United States Patent. Nos. 3,505,878 and 4,262,537. The 0 devices tauqht by these patents must be fastened to the ski with screws and must both be mechanically powered by the transmission of the torque from toothed wheels, thereby adding the impedance of the measuring device to the natural operation of the ski. As the skill of the skier increases such subtleties as the sharpness 5 of a ski edge or even the condition of the wax on the ski bottom become critical when maneuvering at high speeds. Olympic skiing events are frequently decided by one-hundredths of a second. Such a skier would surely appreciate being able to instantly evaluate the effectiveness of a new technique while practising. However, the means for such an 0 indication would have to be placed where it would not alter the ability of a ski edge to cut when making a turn or the like. It is not unusual for a skier to have different skis for different environmental conditions. It would be desirable for the device described above to be easily transferrable from ski to ski. and due to the high cost 5 of skis, for the mounting means not to damage the ski. The ability to remove the device conveniently is also appealing from a security 2 standpoint because the ski could then be left unattended while the skier relaxed elsewhere. Cross-country skiing affords the skier an opportunity to explore areas that are substantially inaccessible by other practical means. This physically exerting sport is often combined with outdoor camping in long lasting excursions many miles from civilization. The weather in such areas can be-quite unpredictable and is capable of rendering conditions whereby a- kier could not visually recognize landmarks or previous tracks in the- snow. A device capable of measuring the distance skied could enable a skier to know his location at all times and to keep traveling with a compass and map. Owing to the nature of cross-country skiing, such a device should be light and compact so as not to add a sϊgnicant amount of weight to the ski upon which it is mounted. !t is t e object of this invention to provide an accurate indication of speed or distance to a skier of snow or water to accomplish the results enumerated above. It is a further object of this invention to provide a non-mechanical method of powering the means for obtaining and displaying speed or distance so as to have a minimum negative effect upon the natural performance of the ski. It is a still further object of this invention to provide a means for displaying the speed or distance digitally so as to provide the information at a glance. It is a still further object of this invention to provide a demountable method of mounting the present device to the ski that does not require the use of tools or cause physical damage to the ski. It is a still further object of this invention to embody the device as simply and as economically as possible so as to make the device amenable to mass production techniques. The invention possesses other objects and features of advantage, some of which with the foregoing, will be apparent from the following description and the drawings. It is to be understood however that the invention is not limited to the embodiement illustrated and described, since it may be embodied to various forms within the scope of the appended claims. SUMMARY OF THE INVENTION In ter s of broad inclusion, this invention employs a microcomputer that calculates the speeds or distance traveled by a skier with a minimum effect on the natural performance and cosmetics of the ski. This device is contained and protected by a housing that is directly attached to the ski. The housing is comprised of a top half and a bottom half the union of which is sealed by a gasket. Clips are disposed around the periphery of the assembled housing halves to provide pressure necessary to form a good gasket seal. A toothed wheel attached to a shaft constrained by the housing to rotate about an axis lateral to the ski is positioned at the rear and extended over the back of, the ski. The wheel is positioned in such a way that it makes contact with the snow or water, thereby causing the wheel to rotate when the assembly moves in the direction of the axis of the ski. Two permanent magnets are attached to the wheel. A non-contact sensor, such as a Hall effect device, is mounted in the housing of the device in such a way as to sense the passage of the magnets in the wheel. Hall effect sensors detect magnetic field changes. The magnets are placed in the wheel such that on a given face of the wheel the North pole of one magnet will be pointed out while the South pole of the other magnet faces out. A signal is sent to the microcomputer when the sensor detects that the magnetic field has changed back to its original polarity, thereby indicating a wheel rotation. The microcomputer is employed to both time and count wheel rotation periods. These data along with the known circumference of the wheel are then used to calculate quantities such as the maximum speed, an average speed over a selected period of time, the total distance traveled during a selected period of time, or the speed last calculated. Results of the above calculations are displayed digitally. BRIEF DESCRIPTION OF THE DRAWINGS FIGURE 1 is a top plan view of the device mounted on the rear of the ski. FIGURE 2 is a fragmentary cross-sectional view taken in the plane indicated by the broken line 2-2 in FIGURE 1. FIGURE 3 is a vertical cross-sectional veiw taken in the plane indicated by the line 3-3 in FIGURE !. FIGURE 4 is a detailed view of the portion of the device encircled by the line 4-4 in FIGURE 1 so as to display the otherwise hidden features. FIGURE ' 5 is a cross-sectional view taken in the plane indicated by the line 5-5 in FIGURE 2. DESCRIPTION OF THE PREFERRED EMBODIMENT The device is contained and protected by a two-part, hollow, elongated, plastic housing. This housing is comprised of a top half 1 and a bottom half 2 as best depicted in FIGURE 2. FIGURES I to 3 illustrate how clips 3 hold the top housing half 1 against the bottom housing half2 and also compress a gasket 4 which serves to seal the union against contaminants such as water. The gasket 4 also clamps the printed circuit board 5 tightly in place against the bottom housing half 2. The top housing half has two apertures. FIGURES 1 and 2 show the window aperture 6 which permits viewing of the digital display 7 which is attached to the printed circuit board 5 below. FIGURE 4 shows the flexible lead aperture 8 through which the flexible lead 9 is passed.. The _ flexible lead 9 is a part of one of the layers of the multi-layered top panel 10, which is attached with pressure-sensitive adhesive 1 1 to the top housing half 1. The top panel 10 contains membrane switches 12 which are used to control the functions of the device. The portion of the top panel 10 that covers the window aperture is transparent and forms a display window 13. Both the window aperture 6 and the flexible lead aperture -8 are completely; covered by the top panel which extends sufficiently beyond them to form a protective seal when the panel is pressed down and adheres to the top housing half. FIGURES 2 and 3 illustrate how the device is attached to a ski 1 . Two thin plastic strips 15 have pressure-sensitive adhesive on one side and a dense pattern of bulb-headed stems, which extend on axes perpendicular to the plane of the plastic strip, on the other side. One plastic strip is adhered to the top face and rear end of a ski while the other plastic strip is adhered to the bottom side of the bottom housing half 2. When the device is pressed down upon the ski such that the plastic strip on the bottom of the device is over the plastic strip on the ski, the two plastic strips engage positively with each other forming a secure method of holding the device to the ski that does not cause permanent damage to the ski such as with screw holes. Means are provided to attach to the device a restraint, such as a strap or cord, which may also be attached to the ski, such as to the binding of the ski. This restraint ring 16 is an integral part of the bottom housing half 2. If. the event of an accident whereby the device could become dislodged from the primary fastening system comprised of the two plastic strips, the device could still remain attached to the ski by virtue of said restraint which would prevent the device from being flung off to either strike someone or become lost. The restraint should not attach the device directly to the skier as this could result in injury to the skier in the event of such an accident. FIGURE 5 illustrates the toothed wheel 17 tightly attached to the stainless steel shaft 18 and to the magnets 1 . The shaft, hence the wheel, is free to rotate in the recesses of the bifurcated part of the plastic housing tήat are formed when the top housing half 1 is attached to the bottom housing half 2. An economical bearing of sufficient quality is thus formed allowing the wheel to rotate with respect to the device and ski. The Hall ? f fect sensor 20 is supported in the top housing half 1 as shown in FIGURE 2. The sensor is placed so that it may detect magnetic field changes induced by the passage of the magnets attached to the wheel. For example, in FIGURE 5 let the top magnet be oriented so that its North pole points out of the right hand face of the toothed wheel 17 while the bottom magnet is oriented so that its South pole points out of this same side. A rotation of the wheel will be indicated by the Hall effect sensor 20 when the magnetic field is sensed to have changed back to its original polarity. This indication is then sent to the microcomputer 21 via the conductive leads (not shown) of the Hall effect sensor 20. FIGURE 3 exaggerates the protrusion of the wheel from the plane formed by the bottom of the ski. This is done so that the wheel may be more easily recognized as such, in actuality, the wheel would only extend about one-sixteenth of an inch. The cross-sectional view of the device in FIGURE 2 shows the major components of the printed curcuit board 5. They comprise the microcomputer 21 , a battery 22, and the digital display 7. Other support electronics such as resistors, capacitors and a crystal are not shown in order to simplify the figure. Having thus described the invention, what is claimed to be new and novel and sought to be protected by Letters Patent is as follows:

Claims: I CLAIM: 1. A device for measuring speed or distance travelled between a vehicle adapted to be attached to a human foot and a relatively immovable surface, comprising: a) at least one wheel rotatably mounted on said vehicle, the perimeter of said wheel adapted to contact the surface over which said vehicle is moving, thus causing said wheel to rotate-; b) a base on said wheel is mounted for rotation; c) means on the base for sensing or counting the number of revolutions of said wheel in point of time for calculating speed or distance of movement of sai vehicle over said surface wherein said sensing or counting means are powered by a power source other than said wheel; d) means for storing information representative of said speed or distance; and e) means for displaying said stored information. 2. A device according to Claim 1 wherein a two-part sensing means is provided cooperatively interposed between said wheel and base. 3. A device according to Claim 1 wherein said stored information is displayed digitally. 4. A device for measuring speed or distance travelled by a ski over any surface, comprising: a) at least one wheel rotatably mounted on said ski, the perimeter of said wheel adapted to contact the surface over which said ski is moving, thus causing said wheel to rotate; b) a base on which said wheel is mounted for rotation; c) means on the base for sensing or counting the number of revolutions of said wheel in point of time for calculating speed or distance of movement of said ski over said surface wherein said sensing or counting means are powered by a power source other than said wheel; d) means for storing information representative oi said speed or distance; and e) means for displaying said stored information. 5. A device for measuring speed or distance travelled by a snow ski, comprising: a) at least one wheel rotatably mounted on said ski, the 8 perimeter of said wheel adapted to contact the snow over which said ski is moving, thus causing said wheel to rotate; b) a base on which said wheel is mounted for rotation; c) means on the base for sensing or counting the number of revolutions of said wheel in point of time for calculating speed or distance of movement of said ski over the snow wherein said sensing or counting means are powered by a power source other " han " said wheel; d) means for storing information representative of said speed or distance; and e) means for displaying said stored information. 6. A device for measuring speed or distance travelled by a water ski, comprising: a) at least one wheel rotatably mounted on said ski, the perimeter of said wheel adapted to contact the water over which said ski is moving, thus causing said wheel to rotate; b) a base on which said wheel is mounted for rotation; c) means on the base for sensing or counting the number of revolutions of said wheel in point of time for calculating speed or distance of movement of said ski over the water wherein said sensing or counting means are powered by a power source other than said wheel; d) means for storing information representative of said speed or distance; and e) means for displaying said stored information. 7. A device for measuring speed or distance travelled between a movable object and a relatively immovable surface, comprising: a) at least one wheel rotatably mounted on said movable object, the perimeter of said wheel adapted to contact the surface over which said movable object is moving, thus causing said wheel to rotate; b) a base on which said wheel is mounted for rotation; c) means on the base for sensing or counting the number of revolutions of said wheel in point of time for calculating speed or distance of movement of said movable object over said surface; and d) wherein said device is detachably mounted on said movable object by means that do not require the use of tools or do not q cause permanent damage to said object 8 A device for measuring speed or distance travelled between a movable object and a relatively immovable surface, comprising a) at least one wheel rotatably mounted on said movable object, the perimeter of said wheel adapted to contact the surface over which said movable object is mowing, thus causing said wheel to rotate, b a base on which said wheel is mounted for rotation, c) means on the base for sensing or counting the number of revolutions of said wheel in point ot time for calculating speed or distance of movement of said movable object over sai surface, and d) wherein said base includes means for attachment of a fl xible restraint the other end of which may be attached to the object of which the speed or distance is being measured 9 A device for measuring speed or distance travelled between a ■ sliding wheeless vehicle a d a relatively immovable surface, comprising- a) at least one wheel rotatably mounted on said wheeless vehicle, the perimeter of said wheel adapted to contact the surface over which said wheeless vehi le is moving, thus causing said wheel to rotate, b) a base en which said wheel is mounted for rotation, c ) means on the base for sensing or counting the number of ' " evolutions of said wheel in point of tme for c alculating oeed cr di stance of movement of said wheeless •'ehicle o*'er said surface wherein said sensing or counting means are oowered j y a cower source other than said wheel , d) means for storing information representative of said speed or distance, and e) means for di pl ying said stored information 10 A device according to Claim 9 wherein a two-part sensing means is provided cooperatively interposed between said wheel and base 1 1 A device according to Claim 9 wherein said stored information 1? displayed digitally

Inventors: CAMERON JOHN F, CAMERON, JOHN, F.
Applicants: CAMERON JOHN F, CAMERON, JOHN, F.
Application year: 1985
Main classification: A63C11
IPC codes: A63C5, A63C11, G01C22, G01P1, G01P3