US3398970A

US3398970A - Ski sled

Info

Publication number: US3398970A
Application number: US569910A
Authority: US
Inventors: Horiuchi Kotaro
Original assignee: Nippon Gakki Co Ltd
Current assignee: Nippon Gakki Co Ltd
Priority date: 1966-08-03
Filing date: 1966-08-03
Publication date: 1968-08-27
Anticipated expiration: 1985-08-27

Description

Aug. 27,1968 KOTARO HoRlucHl SKI SLED 3 Sheets-Sheet 1 Filed Aug.

Aug. 27, 1968 KoTARo HoRlUcHl SKI SLED 3 Sheets-Sheet 2 Filed Aug. 5, 1966 Aug. 27, 1968 KOTARO HORIUCHI SKI SLED 3 Sheets-Sheet 3 Filed Aug. 3, 1966 20 40 INCLINED ANGLE OF SKI SLED BODY (DEGREE) Q cm2-402- United States Patent O 3,398,970 SKI SLED Kotaro Horiuchi, Hamamatsu-shi, Japan, assignor to Nippon Gakki Seizo Kabushiki Kaisha, Hamamatsu-shi, Japan, a corporation of Japan Filed Aug. 3, 1966, Ser. No. 569,910 11 Claims. (Cl. 280-16) ABSTRACT OF THE DISCLOSURE A three-ski sled having a body and front ski and rear skis connected thereto which follow the inclination of the body as effected by a leaning action of the rider. The sled is so constructed that the edging of the skis are fully utilized with the rear skis being canted inwardly and having foot 'binding means. The rear skis are rotatably supported by front-lifted longitudinal axles, so that the steering effect may also be obtained fby the rear skis with the inclination of the body.

This invention relates to an improvement :in a ski sled having one front ski for directing the course and two rear skis, and especially to improvements in the steering mechanism of such ski sleds.

The three-ski sleds of this kind have been conventionally available. These ski sleds were comprised of one front ski arranged at the front of a body so as to be steered by a handle and two rear skis arranged right and left at the rear thereof. In the ski sleds of this kind the turning force Iwhich is necessary for making a turn during running is obtained Iby changing the direction of the front ski and inclining the skis right or left. However, in the conventional ski sleds of this type, the inclination is given only to the front ski and said inclination is given `only by the steering angle and the caster angle of the steering shaft of the front ski so that the inclination of the ski is not sufficient resulting in slip. And, upon turning the ski sleds, the outside edge of the turn of each ski is also engaged on the snow surface, so that there is a drawback in that the turning force is linevitably destroyed. Thus, the conventional type ski sleds have such drawbacks that they can not make a quick turn, and are in danger of falling over. Also, it has been difficult to traverse a slope by using ski sleds in the prior art. There have also been available such sleds Lin which the turning force was attempted to be produced by inclining the right and left skis, however, in such sleds, the handling was too complicated to realize a practical use, and also they were not sufficiently maneuverable.

It has been discovered through close studies of sleds, that a sled cannot be properly handled only by steering the front ski as in a car, and that for superior maneuverability the sled should be so constructed as to be driven also by utilizing the edging effect of the skis just as in skiing. For the eiective edging of the skis, the skis have to be inclined (or tilted) and the riders weight should be properly transmitted on each olf them. This invention eliminates such drawbacks of the prior art and provides a three-ski sled having a high degree yof maneuverability and stability.

An object of this invention is to provide suiiiciently great turning force by turning the front ski in the intended direction and inclining the three skis at the same time toward the inside of the intended turn for a right or left turn of the sled, and by the rider applying his weight on the ski, which is on the outside of the turn, through his leg with his body oi the seat.

It is another object of the invention to permit the sled to make a quick turn and a quick stop with an increased maneuverability iby providing sufciently great turning 3,398,970 Patented Aug. 27, 1968 ICC force by turning the front ski for directing and inclining suitably the three skis at the same time for the right or left turn of the sled.

Still another object of the invention is to obtain said inclination of the skis for making a turn by a natural and simple operation in which the rider leans inwardly.

Another object of the invention is to provide a ski sled which may not sideslip and can traverse a slope by suitable inclination of the skis.

A further object of the invention is to provide a ski sled which may be operated naturally and simply by leaning the body of the rider toward the mountain side for the inclination of `each ski on traversing a slope.

A still further object of the invention is to provide a ski sled lwhich is driven in the same manner in which skis are maneuvered during skiing.

Yet another object of the invention is to provide a three-ski sled having superior stability so that even the beginner may ride thereon with great ease.

The characteristics of this invention will be described hereinafter with reference to the accompanying drawings illustrating embodiments of the invention.

In the drawings:

FIGURE 1 is a schematic View of the sled structure of the invention;

FIGURE 2 is a rear view of the sled of the invention standing substantially upright;

FIGURE 3 is a rear view of the sled of the invention in inclined position;

FIGURE 4 is a longitudinal side view of the sled of this invention;

FIGURE 5 is a section taken along the line V-V in FIGURE 4;

FIGURE 6 is a longitudinal side section of the Ifront of the sled illustrating another embodiment of the invention; and

FIGURE 7 is a diagram showing the relationship between the angle of inclination of the sled body and those of the front ski and the right and left skis.

Referring to FIGS. l and 4, the body of the ski sled generally shown `by numeral 1 is made of laminated liberglass reinforced plastic and comprises the main body portion 2 including front portion 2a and rear portion 2b. In said front portion 2a, there is fitted, with a proper caster angle, head pipes 4 of hard polyethylene or the like for supporting a steering shaft 16 of a steering handle 17. The steering shaft 16 is inserted into said head pipes 4, and at the lower end of the shaft 16 there is provided a boss 19a and a collar 20a thereabove. There is provided a coil spring -20 between the lower head pipe 4 and the collar 20a, while the =boss 19a of the steering shaft -16 and the metal fitting 27 of the front ski 18 areconnected rotatably by means of a lateral pin 19. The coil spring 20 serves not only for furnishing a front cushioning action for the :body 1, but also for maintaining a good distribution of the load in the rfront ski in case the sled is inclined right or left or under other various possible conditions. Thus, it provides a good road holding in cooperation with the rotatably pivoted front ski 18. In the drawing 21 is an elastic string-like regulator element 22 connected to the

metal tting

27, and 22a is a -rnetal -tting for engaging the regulator element 21, the a'bove ele-ments resisting an excessive rotation of the front ski as in the case of jumping, thus preventing the sled from falling over upon landing. 29 is a screw to fix the steering handle 17, and its end is tted in a nut 38 xed to a boss 37 of the steering handle 17 and fastens the steering handle 17 to the steering shaft 16. A slit 39 on the side of `boss 37 is -for securing said fastening.

There is provided a cover 1S -on the upper part of the rear portion 2b of the body which serves as a knee rest and a seat as well and is padded with an elastic foam material such as rubber sponge, while at the lower side of said rear portion 2b there is provided a bracket 3 pivotally supported by an axle 23 which is held at both sides of the rear portion 2b of the body 1. A longitudinal axle 6 is secured to the lower end portions of both front and

rear sides

3a, 3b of Said bracket 3, and a bridge 5 cornprising an arched leaf spring of metal or iiberglass reinforced plastic is pivotally connected to above said axle 6. Said bridge 5 is fastened by a pair of

auxiliary plates

5a and 5b on both sides, and when said bridge 5 comprises a leaf spring, it affords a cushion action to the sled. In this case, a reinforcing bar `26 is arranged substantially in the middle of the

sides

3a, 3b of the bracket 3 so as to reinforce said bracket 3. Each end of the bridge 5 is fixed to the metal fitting `8 of a rear ski 7 'by a longitudinal axle 9 extending through a receiver plate 9a and thereby the rear skis are pivotally supported. As seen in FIG. 4 the axles are inclined forwardly and upwardly for a reason to be described later. A lever 1v1 is provided at the rear side of each metal fitting 8, and a link 12 is provided |between the side edge of the rear side 3b of the bracket 3 and the lever 11 of the metal fitting 8 of each rear ski 7. This link plays an important part for producing a turning force by inclining the rear ski 7. It is possible to optionally choose the inclination characteristic of both right and left lrear skis by properly selecting the length of lever 11 and link 12 and the position where the link 12 is tted to the bracket 3. A metal stay 24 to reinforce the lever 11 is arranged between the lever 11 and the rear ski 7. A step 13 with a band 14 for binding the shoes is provided into the front portion of the rear ski 7, and the front ends of both rear skis 7 are coupled pivotally to a bar 10 through longitudinal pins 40, said bar being pivotally supported at its center from the front portion 2a of the body 1 through a longitudinal pin 10a thereby constituting a seesaw mechanism. Attention should be paid in FIG. 4 to the fact that the bar 10 supports the tips of the rear skis to keep the `front portions of the rear skis high above the plane of the front ski. In this way, the weight borne by the front ski is increased to provide an improved steering of the sled. In addition, when the right rear ski is pressed down, the left rear ski is slightly lifted, which will result in better conditions for a left turn. The pin 40 may not necessarily -be in alignment with extension of the axle 9, nor the pin 10a on the axle 6.

The alignment of the rear ski of the invention will be described as follows:

v(1) When the front ski 18 is kept substantially level (i.e. a condition wherein the body 1 is upright), the right and left skis 7 are inclined somewhat inwardly, namely, the inclination being kept at the angle Cl degree in FIGURE 2, whereby the right and left rear skis 7 can be kept stable in case of straight gliding with the inside edges ofthe rear skis biting the snow.

(2) The rear skis have a toe-out configuration in the unloaded state, and for example, the distance between the rear ends of both rear skis is 625 to 63() mm., whereas that between the front ends of both rear skis is 650 mm., which forms a -toe-out of approximately to 25 mm. This construction is necessary when the bridge 5 is made of spring material, so that the rear skis may lie parallel when the rider sits on the seat and the spring bridge is widened by his weight.

(3) The axles of the rear skis have, for instance, an angle of forward elevation BS degrees (FIG. 4), whereby movement in the case of a quick `turn can be improved. Namely, when the body 1 is inclined toward the inside of the intended turn, the front portion of the rear skis 7 move toward the outside of the turn and the rear ends toward the inside of the turn, therefore, the movement becomes better than that of steering by the lfront ski 8 only. When the rider turns the steering handle to the left and inclines the body to the left, the front ski turns to the left and the rear skis turn to the right, thus the sled is turned both by the front ski and the rear skis. In case the pin 40 is not on the extension of the axle 9, or the pin 10a is not on rthe extension of the axle 6, an elastic distortion is produced on each part by the leaning of the body 1, with resultant improved stability.

The sled of the invention is constituted as described above. The discussion will next be directed to the inclining action of each ski. As shown in FIGURE 2, if the body 1 is kept substantially upright, each ski is substantially on the same plane and accordingly the turning force does not act. Under this condition, a straight sliding is possible, and even if the steering handle 17 is tu-rned in this condition, the front ski sideslips and no effective turning movement is obtained. However, when the body 1 is leaned sideways about the axle 6 as a center, asshown in FIGURE 3, the front ski 18 is inclined at the same angle as the body and the right and left rear skis 7 are also inclined, by the action of link 12, in the same direction. When the steering handle 17 is simultaneously turned in the direction in which the body 1 has been leaned, a large turning force is obtained, thus enabling the sled to make a quick turning movement. In this case, the angle of inclination of the front ski 1S is equal to that of the body 1, but the ratio of the angle of inclination of the rear ski 7 to that of the body 1 is freely selected and further the inclination characteristic of the inside and outside can be differentiated, as well. Thus, the ratio of the turning force shared by the three skis is freely selected. An actual example is shown bel-ow.

CONDITION OF INCLINATION The above example is embodied in FIG. 7. In any case, the outer ski of the turn should have the greater inclination. To make an excellent turn with this sled, the rider keeps his weight off the seat and applies his weight through his legs mainly on the outside ski of the turn. Outstanding results are obtained if the rear skis are connected to the body in such a manner that the angle difference of inclination between, the two rear skis increases as the inclination angle itself increases, yas shown in the table and in FIG. 7.

As described in detail above, it is possible with this invention not only to turn the front ski but also to selectively incline each of the three skis for a turn and to control the weight applied to the skis directly by the legs of the rider, therefore, a large turning force is obtainable to allow a quick turn or a quick stop, thereby greatly improving the maneuverability of the sled. According to the invention the inclination of the skis prevents the sled from sideslipping and also the sled can easily traverse a slope with the weight of the rider shifted, to the mountain side on sliding. Furthermore, as the inclination of the skis is obtainable from the natural operation in which the rider leans inwardly when turning or to the mountain side when traversing, the handling of the sled is quite easy, and in addition the sled, because of its three-ski constitution, is highly stable, thus assuring the beginner of an easy control of the sled.

In the embodiment shown in FIGS. 1 to 4, the lower end of the steering shaft 16 is coupled directly to the ski 18, permitting the up-and-down movement of the front ski to be directly transmitted to the handle 17 and thus causing large and small shocks to be felt by the rider in his hands, with consequent uncomfortable driving. However, according to the embodiment shown in FIG. 6, these shocks are limited to a minimum. In the embodiment of FIG. 6, the arrangement is the same as that of FIGS. 1 to 4, except for the form of the steering shaft 16 and the provision of a lower flange 16a of the steering shaft 16, links 34, 35 to couple said flange 16a and the metal fitting 27 of the front ski 18, and a rubber pad 36 on the front ski 18. A sliding axle 32 is inserted into the bore of the steering shaft 16 from below and the lower end of said sliding axle 32 is rotatably connected to the metal fitting 27 xed to the front ski 18 through a lateral pin 19. A spring is arranged between the lower flange 16a of the steering shaft 16 and the collar 20a of the sliding axle 32, and the links 34, 35 are connected between Ithe front end of said flange 16a and the metal fitting 27. Thus, in the embodiment shown in FIGURE 6, the yup-and-down movement of the front ski 18 is absorbed by the coil spring 20, and the sliding axle 32 slides along the inside of the steering shaft 16. Therefore, the up-'and-down movement of the front ski 18 is never transmitted to the steering shaft 16 nor to the steering handle 17. The links 34, act to transmit the steering rotation of the steering shaft 16 to the front ski 18, independently of the shock absorbing action of the coil spring 20.

The present invention will be practised as described above in the preferred embodiments, but it should be understood that the invention is not limited to the above, and other changes and modifications can be made without departing from the spirit of this invention.

What is claimed is:

1. A ski sled comprising a body, a front ski and a pair of rear skis -coupled to said body, a rotatable steering shaft in said ibody at the front thereof, said front ski being connected to said steering shaft for rotation therewith, a bridge member pivota-bly connected to said body at the rear thereof, means supporting said rear skis from said bridge member in spaced relation on either side of said body, said means including an axle for each rear ski extending longitudinally thereof and supported from the bridge member to extend generally forwardly and upwardly such that the front ends of the rear skis are raised above the level of the front ski, said rear skis being rotatably mounted on their respective axles, link means connecting the body and said rear skis to enable the rear skis to follow inclination of ythe body and binding means on the rear skis for the shoes of a rider.

2. A sled as claimed in claim 1 comprising means pivotably connected to said .body and connecting said rear skis together at the front ends thereof.

3. A sled as claimed in claim 2 wherein said means connecting the front ends of the rear skis comprises a bar having a center pivotably connected to said body and ends pivotably connected to the front ends of the rear skis.

4. A sled as claimed in claim 2 wherein said bridge member is an arched spring member having ends connected to the axles of the rear skis, said ends having a transverse spacing which is less than the transverse spacing of Vthe front ends of the rear skis whereby the rear skis when unloaded point outwards in the forward direction.

5. A sled as claimed in claim 4 wherein the rear skis are laterally tilted downwards and towards one another at respective angles of 1.

6. A sled as claimed in claim 5 wherein the angle of inclination of the axles of the rear skis is 5.5.

7. A sled as claimed in claim 1 wherein said link means comprises a linkage in which the angular difference of inclination between the two rear skis increases as the angle of inclination of the body increases.

S. A sled as claimed in claim 1 comp-rising a head pipe in said body, said steering shaft being rotatably and slidably supported in said head pipe, a steering handle fixed to the upper end of said steering shaft, a transverse pin at the lower end of said steering shaft, said front ski :being supported pivotally by said transverse pin, a collar fixed to the lower end of said steering shaft and a coil spring -between said collar and the front of said body.

9. A sled as claimed in claim 8 comprising an elastic element connecting said steering shaft and the rear of the front ski, and a fitting on the front ski engaging said steering shaft and cooperating with said elastic element to resist rotation of the front ski relative to said steering shaft.

10. A sled as claimed in claim 1 comprising a head pipe in said body, said steering shaft being rotatably and slidably supported in said head pipe, a handle fixed to the upper end of said steering shaft, said steering shaft being hollow, an axle slidably received in said steering shaft, and extending therefrom, a transverse pin on the latter said axle, said front ski being pivotably supported on said transverse pin, a collar fixed to `the lower end of said 'axle in the steering shaft, a flange secured to the lower end of the steering shaft, and a coil spring between said collar and shaft.

11. A sled as claimed in claim 10 comprising an elastic element connecting said steering shaft and the rear of the front ski, and a fitting on the front ski engaging said steering shaft and cooperating with said elastic element to resist rotation of the front ski relative to said steering shaft.

References Cited UNITED STATES PATENTS 540,295 6/1895 Beebe 280-25 1,264,490 4/1918 CrOWe 280-16 FOREIGN PATENTS 97,744 3/ 1924 Austria.

467,025 1 1/1951 Italy.

498,286 9/ 1954 Italy.

499,656 11/1954 Italy.

928,569 5/1955 Germany.

BENJAMIN HERSH, Primary Examiner. I. SIEGEL, Assistant Examiner.