Abstract:
A typically one-rider non-powered sports/recreational vehicle has a main body that can be easily converted between a wheeled coaster-wagon configuration and a snow-sled configuration with runners. Typically there are four wheels or four runners: two at front, steerable from a handlebar, and two fixed at rear. For braking in the coaster-wagon configuration, a pair of brake shoe pads, attached to the handlebar, press against the front tires to act as brake shoes when the handlebar is twisted radially via a pair of user handgrips. In the snow-sled configuration, a braking panel, attached centrally on the handlebar, moves downwardly to brake by engaging oncoming snow. In normal use as a coaster or sled, when not braking, this braking panel is nested in an unobtrusive location immediately beneath the front of the main body platform, retained there by spring action that also provides braking hold-off in the coaster-wagon configuration.

Description:
FIELD OF THE INVENTION 
   The present invention relates to the field of non-powered personal sports and recreational vehicles and more particularly to such vehicles with capability of conversion between a snow-sled configuration and a wheeled coaster-wagon configuration. 
   BACKGROUND OF THE INVENTION 
   Non-powered sleds and coaster-wagons have been known for many years as separate personal sports and recreational sports vehicles, especially for youngsters, and typically, due to their inherent seasonal usage, many sleds take up valuable storage space while wagons are in use, and vice-versa. Such vehicles are often equipped with steering capability, typically via a front pair of wheels on a personal wagon or, less frequently via front runners of a large snow-sled; however, while combined steering and braking control has been known on coaster-wagons, braking on snow-sleds is virtually unknown and unavailable. 
   DISCUSSION OF KNOWN ART 
   A popular type of one-rider children&#39;s snow-sled is configured with a centrally-pivoted transverse manual steering handle near the front, made and arranged to bend metal runners in a manner to provide a very limited range of steering capability. 
   Convertible coaster/sleds have been proposed, but typically do not include a brake, even for the coaster-wagon mode. Where a brake is provided it typically operates separate from the steering and braking is provided only in the coaster-wagon mode, not in the snow-sled mode. 
   Thus conventional children&#39;s sleds have tended to lack braking and to provide only minimal steering capability. 
   OBJECTS OF THE INVENTION 
   It is a primary object of the present invention to provide a dual mode recreational vehicle, primarily for one rider, that is readily convertible between a coaster-wagon configuration with wheels and a snow-sled configuration with runners. 
   It is a further object to provide improved steering capability and braking capability, both operable and functional in both the coaster-wagon configuration and the snow-sled configuration. 
   It is a further object to provide an integrated steering and braking system that enables the rider to operate both steering and the braking in both the coaster-wagon configuration and the snow-sled configuration from a single user control element. 
   SUMMARY OF THE INVENTION 
   The foregoing objects have been met in the invention of a typically personal non-powered sports/recreational vehicle with a main body that can be easily converted between a wheeled coaster-wagon configuration and a snow-sled configuration with runners. Typically there are four wheels or four runners: two at front steerable from a pair of user handgrips of a handlebar and two fixed at rear. For braking in the coaster-wagon configuration, a pair of brake shoe pads, attached to the handlebar, press against the front tires to act as brake shoes when the handlebar is twisted radially via the handgrips. In the snow-sled configuration, a braking panel, attached centrally on the handlebar, moves downwardly to brake by engaging oncoming snow. In normal use as a coaster or sled, when not braking, this braking panel is nested in an unobtrusive location immediately beneath the front deck region, retained there by spring action that also provides braking hold-off in the coaster-wagon configuration. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a plan view of a convertible vehicle of the present invention in the coaster-wagon configuration, equipped with four wheels. 
       FIG. 2  is a side elevation of the vehicle of  FIG. 1 . 
       FIG. 3  is a front elevation of the vehicle of  FIGS. 1 and 2 . 
       FIG. 4  is a cross-section taken through axis  4 — 4  of  FIG. 2 . 
       FIG. 5  is a plan view of a vehicle of the present invention in the snow-sled configuration, equipped with four runners. 
       FIG. 6  is a side elevation of the vehicle of  FIG. 5 . 
       FIG. 7  is a cross-section of the primary snow-sled configuration taken through axis  7 — 7  of  FIG. 6 . 
       FIG. 8  is a cross-section of the primary snow-sled configuration taken through axis  8 — 8  of  FIG. 6 . 
       FIG. 9  is a cross-section of a secondary (axle-removed) snow-sled configuration taken through axis  7 — 7  of  FIG. 6 . 
       FIG. 10  is a cross-section of the secondary snow-sled configuration taken through axis  8 — 8  of  FIG. 6 . 
       FIG. 11  is a side elevation of the front portion of the vehicle of  FIGS. 1–4  showing braking applied in the coaster-wagon configuration. 
       FIG. 12  is a front elevation of the subject matter of  FIG. 11 . 
       FIG. 13  is a side elevation of the front portion of the vehicle of  FIGS. 5–8  showing braking applied in the snow-sled configuration. 
       FIG. 14  is a front elevation of the subject matter of  FIG. 13 . 
   

   DETAILED DESCRIPTION 
   In  FIG. 1 , a convertible vehicle of the present invention is shown in plan view in a coaster-wagon configuration  10 A having a main body with a pair of straight side rails  12 A and  12 B, a curved front rail  12 C, three deck panels  14 A,  14 B and  14 C, a pair of handgrips  16 A and  16 B, and a set of four identical wheels  18 , two at front and two at the rear. 
   A handlebar assembly includes handgrips  16 A and  16 B fitted to the ends of a transverse metal handlebar to which are attached a pair of coaster brake pads  16 E and  16 F at wheel locations and, optionally, a snow-sled brake panel  16 D. The handlebar assembly is part of a front carriage steering assembly that is mounted pivotally by a pivot bolt  20  to the main body of the vehicle and that carries a front axle for the front pair of wheels  18 . 
     FIG. 2  is a side elevation of the coaster-wagon  10 A of  FIG. 1  showing the two right hand side wheels  18 . The front carriage steering assembly receives support by a central diagonal brace member  26 . The transverse handlebar is attached to the steerable front carriage assembly in such a manner that, in addition to turning the front carriage assembly for steering, it can be oriented axially by the user for braking by a clockwise twisting action such that the ends of handgrips, e.g. the left hand end of handgrip  16 B as shown, move upwardly. 
   At the rear of the vehicle, wheels  18  rotate on an axle supported by inverted-U-shaped bracket  22  which receives support from a pair of diagonal brace members  24 , one on each side, fastened to side rails  12 A and  12 B. 
   A coil spring  28  has one end hooked into an opening in brace member  26  and the other end attached to the handlebar assembly in a manner to exert torque in a counterclockwise direction (as viewed here) to hold the orientation of handgrip  16 B, coaster brake pad  16 F, and sled brake panel  16 D as shown, until actuated by the user by twisting to apply braking. A single spring  28  would be attached centrally to the handlebar, i.e. close to the pivot point of the front carriage to minimize the effect on steering. Alternatively, and preferably, two coil springs  28  can be incorporated and attached to the handlebar assembly, offset to opposite sides from center, so to provide a balanced arrangement that automatically returns the steering to a centered neutral position as the default condition in the absence of any user-exerted force applied to the handgrips  16 A and  16 B. Thus the coil springs  28  act automatically in default, i.e. in the absence of force applied to the handlebar by the user, to perform two separate and different functions: brake hold-off and steering-centering. 
   In  FIG. 3 , the front elevation of the vehicle of  FIGS. 1 and 2 , handlebar  16 C is seen along with handgrips  16 A and  16 B, coaster brake pads  16 E and  16 F and sled brake panel  16 D which in a substantially horizontal orientation. The front carriage steering assembly is seen including the two front wheels  18 , axle  30  traversing “axle” holes in the two legs of the main inverted-U-shaped bracket  32 , and, immediately above axle  30 , a reinforcing cross-brace  32 A, attached pivotally to diagonal brace  26 . The top side of bracket  32 , retained by pivot bolt  20 , bears rotatably against a metal plate  34  which is attached to the underside of the top deck of the vehicle near the front end, behind front rail  12 C. The four wheels  18  are each retained by an ornamental nut  30 A, typically an “acorn” type cap nut, threaded onto each end of the two axles  30 . 
     FIG. 4  is a cross-section taken through axis  4 — 4  of  FIG. 2 , showing rear wheels  18  with axle  30  mounted through bearing holes in inverted-U-shaped bracket  22  and its diagonal supports  24 . Attached to the top region of bracket  22  are seen the two side rails  12 A and  12 B and the three deck panels  14 A,  14 B and  14 C. 
   In an easy conversion from the coaster-wagon configuration  10 A to the snow-sled configuration, the four wheels  18  are removed and replaced by four snow-sled runner units: a front pair and a rear pair, by simple removal and reinstallation of the four ornamental nuts  30 A. 
     FIG. 5  is a plan view of the vehicle of the present invention after conversion to the snow-sled configuration  10 B, equipped with four runner units:  38 A and  38 B at the front and  40 A and  40 B at the rear. 
     FIG. 6  is a side elevation of the subject matter of  FIG. 5  showing the right front runner unit  38 B and the right rear runner unit  40 B, retained by nuts  30 A and riding on ground covered by a layer of snow  46 . The rear runner unit  40 B includes a main vertical triangular strut portion that engages the rear axle, and an auxiliary vertical forward strut portion  42  configured at top with a horizontal inwardly-facing tab that is retained in a slot opening provided by a U-shaped bracket  44  attached to the underside of right handrail member  12 B. 
     FIG. 7 , a cross-section taken through axis  7 — 7  of  FIG. 6 , shows handlebar  16  passing through holes that serve as bearings at both sides of inverted-U-shaped bracket  32 , and shows the vertical strut region of front runners  38 A and  38 B retained against bracket  32  by ornamental nuts  30 A and spacers  30 B. 
   Since the axle  30  must be made long enough to accommodate the thickness of the hubs of wheels  18  (refer to  FIG. 4 ), which is greater than the thickness of the runner units  38 A,B (and  40 A,B,  FIG. 8 ), the snow-sled configuration  10 B requires tubular spacers  30 B at the ends of the axles  30  between the nut  30 A and the corresponding runner unit. Spacers  30 B may be deployed as separate items, or they may be each permanently attached to the corresponding runner unit. 
   Front runner units  38 A and  38 B are shaped with an inward offset to conform with the shape of bracket  32  and are further retained by fixed studs  36 , near the top of the strut, engaging mating holes provided in bracket  32 . 
     FIG. 8 , a cross-section taken through axis  8 — 8  of  FIG. 6 , shows the rear runner units  40 A and  40 B retained on rear axle  30  by nuts  30 A and spacers  30 B, and retained near the top of the vertical strut by fixed studs  36  engaging mating holes provided in bracket  22 , in generally the same manner as in the front runner units. 
     FIGS. 9 and 10  are cross-sections taken through axis  7 — 7  and axis  8 — 8  of  FIG. 6  respectively, showing an alternative snow-sled configuration  10 C wherein the two axles are removed in the conversion, and the runner units  38 A,B (FIG.  9 ) and  40 A,B ( FIG. 10 ) are each attached by a machine bolt  48  traversing the holes vacated by removal of the axles and each retained by a nut  30 A, which may be the same ornamental nut that retains the wheels in the coaster-wagon configuration  12 A, Bolts  48  are preferably made with a large square head to avoid the need for holding with a second wrench while tightening nut  30 A. 
   Compared to snow-sled configuration  10 B, the absence of axles in configuration  10 C offers the advantages of reducing potential drag by the axles in deep snow, eliminating the need for spacers  30 B, and eliminating the surplus axle-end extensions (see FIGS.  7 , 8 ). However, as disadvantages, conversion requires removal/installation of the two axles, and bolts  48  must be procured, handled and stored as loose standby items along with the runner-units during seasons when the vehicle is in the coaster-wagon configuration. 
     FIGS. 11–14  illustrate the implementation of braking in the coaster-wagon configuration  10 A and in the snow-sled configurations  10 B and  10 C 
     FIG. 11  is a side elevation of the front portion of the vehicle  10 A of  FIGS. 1–4  showing braking applied in the coaster-wagon configuration  10 A. Torque applied by the user in a clockwise direction, as viewed here, has pressed the brake pad  16 F against the outer tire portion of wheel  18  to as to apply frictional braking to both front wheels. The axial rotation of the handlebar, against the tension of spring  28 , has moved the sled brake panel  16 D to a position slightly separated from the front rail  12 C as shown. 
     FIG. 12 , a front elevation of the subject matter of  FIG. 11 , shows that when braking is applied to the front wheels  18  by pads  16 E and  16 F, the rotation of handlebar  16  has raised the handgrips  16 A and  16 B to approximately a horizontal position as seen in this view (and in  FIG. 9 ) from their normal slightly downward default orientation with braking released as seen in FIGS.  2 , 3 , 6  and  7 . The small downward displacement of snow-sled brake panel  16 D as seen in  FIG. 10  imposes no practical effect on the utilization of the vehicle in its coaster-wagon configuration. 
     FIG. 13  shows a side elevation of the front portion of the snow-sled of  FIGS. 5–10  showing how braking is applied in the snow-sled configurations  10 B and  10 C. With considerable further clockwise rotation of the handlebar  16 , the handgrips  16 A and  16 B are seen as being inclined upward to near their highest position, and sled brake panel  16 D is now seen to extend well below the level of the axle holes, where it slows the sled by engaging oncoming snow, which will tend to build up and form a pack at the front of the sled. 
     FIG. 14  shows a front elevation of the subject matter of  FIG. 13 . Apart from the presence/absence of small axle segments in this view,  FIG. 14  applies to both snow-sled configurations  10 B and  10 C. 
   The shape of sled brake panel  16 D as shown corresponds with the shape of the front rail  12 C (FIGS.  1 , 5 ) so that, in normal use, panel  16 D is largely concealed, except for when braking is applied by the user in the snow-sled configuration. Functionally, the invention could be practiced with the brake panel  16 D and/or the front rail  12 C made in a different size and/or shape, as a matter of design choice. It may be possible to form pads  16 E and  16 F together with sled brake panel  16 D from a single plate of metal. 
   The two holes shown in front rail  12 C in  FIGS. 12 and 14  are provided for optional deployment of a pull-rope (not shown) in the wagon configuration  10 A or in either sled configuration  10 B of  10 C. The end of the pull-rope would be inserted through these holes and knotted behind front rail  12 C for retention. 
   There are other options whereby the invention could be practiced, for example with more complex fastening methods and/or additional hardware for fastening the axles and/or the runners. As an alternative, the sled brake panel  16 D (FIGS.  2 , 6 , 10 , 12 ) could be made user-removable and/or made in a different size and/or shape. 
   The invention could be practiced with the ends of the handlebar  16 C and handgrips  16 A and  16 B shaped and positioned other than shown and described above; e.g. if the handlebar is bent at the ends to make the handgrips substantially perpendicular to central portion of the handlebar and oriented upwardly as the default position, this would allow braking to be applied by pushing the handgrips forward and downward, which could be done either by the hands or the feet of the user, or even by one hand or foot. 
   The convertible coaster/sled can be considered as three packages; a first conversion package including four wheels  18 , the main package consisting of the main body that would remain after removing the wheels from the coaster-wagon configuration, and a second conversion package including the four runner units which are added to convert the main body into the snow-sled configuration. As an alternative to producing the subject of the invention as a totally new product, the concept envisioned and the structure of the illustrative embodiment described above holds open the possibility of implementing the invention as a modification/improvement based on starting with a known coaster-wagon product. For example U.S. Pat. No. 2,103,998 to inventor F. G. Birkhead discloses a WHEELED COASTER that could possibly serve as the main body and the first conversion package, to be supplemented by the addition of the items of the second conversion package to fully implement the convertible coaster-sled of the present invention 
   The invention may be embodied and practiced in other specific forms without departing from the spirit and essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description; and all variations, substitutions and changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.