US3526412A

US3526412A - Ski-bob with rear ski runner forwardly suspended

Info

Publication number: US3526412A
Application number: US748077A
Authority: US
Inventors: George E Garcia
Original assignee: Individual
Current assignee: Individual
Priority date: 1968-07-26
Filing date: 1968-07-26
Publication date: 1970-09-01
Anticipated expiration: 1987-09-01
Also published as: DE1937236A1; CH497998A; FR2013829A1

Description

p 1970 G. E. GARCIA 3,526,412

SKI-BOB WITH REAR SKI RUNNER FORWARDLY SUSPENDED Filed July 26. 1968 3 Sheets$heet 1 EO/PGE E. GARC/A 6 INVENTOR 4 r U 34 ////A BY 1- 5 24 3 ATTORNf) Sept. 1, 1970 G. E. GARCIA 3,526,412

SKI-BOB WITH REAR SKI RUNNER FORWAHDLY SUSPENDED 3 Sheets-Sheet 2 Filed July 26, 1968 GEORGE E. GARCIA [NVENTOR 46r I 55b 4% .1. ll 41 I I HZ 7 ATTORNEY SKI-BOB WITH REAR SKI RUNNER FORWARDLY SUSPENDED Filed July 26, 1968 3 Sheets-Sheet a 46a GEORGE E. GARC/A INVENTUR v 4Hr ATTORNEY United States Patent 3,526,412 SKI-BOB WITH REAR SKI RUNNER FORWARDLY SUSPENDED George E. Garcia, Houston, Tex. (2370 Broadway St., San Francisco, Calif. 94115) Filed July 26, 1968, Ser. No. 748,077 Int. Cl. B26b 13/04 US. Cl. 280-16 9 Claims ABSTRACT OF THE DISCLOSURE The ski-bob comprises a forward ski runner, a steering post connected thereto to pivot in an upright longitudinal plane, a rear ski runner, a frame with forward part pivotally connected to the steering post for frame to swing across direction of ski-bob travel, and with frame rear part connected to the rear ski runner to pivot in an upright longitudinal plane. Thus, with the forward, upwardly curved part of the rear ski runner yieldably connected to the frame, the ski-bob may closely follow a track undulatory in elevation and curved in plan view.

The invention relates to a ski-bob that has the upwardly curved leading part of a rear ski runner yieldably disposed with relation to the frame, thus enabling the skibob more closely to follow a track that is undulatory in elevation and curved in some degree in plan view, whereby the track is not broken up over its undulations as in the case of conventional ski-bobs having a single ski runner, or a rear ski runner with a leading part that is substantially rigidly connected to the frame.

As a primary object the invention provides an inventive ski-bob construction with a rear ski runner having its leading part yieldably disposed with relation to the frame whereby the ski-bob may more closely follow a track that may be undulatory in elevation and curved in degree in plan view.

It is also an important object of the invention to provide a ski-bob of this class with lower end of steering post and lower end of rear frame part both leaf spring connected to respective transverse pivots across respective forward and rear ski runners.

It is yet another and important object of the invention to provide a ski-bob of this class with the leading part of the rear ski-runner variously yield-ably connectable to the frame, as by an elastic cord connecting it to the forward part of the frame near the lower end thereof, or to the central part of the frame thereabove.

It is also another and important object of the invention to provide a ski-bob of this class in which the seat is forwardly connected to the upper, central part of the frame, with the rear part of the seat being yieldably supported by shock absorber means disposed between seat and rear ski runner.

It is still another and further object of the invention to provide a ski-bob of this class which may be easily assembled with a minimum number of parts over conventional ski-bob combinations, but in manner that the assembled ski-bob may more readily follow in undulatory track in elevation that is curved in plan view.

Other and further objects will be apparent when the specification is considered in connection with the drawings, in which:

FIG. 1 is an isometric view of one embodiment of the invention with leading part of rear ski runner shown, partially diagrammatically, connected in yieldably manner, to the lower end of the forward part of the frame;

FIG. 2 is an elevational view of a ski-bob constructed substantially in correspondence with FIG. 1, advancing over a track undulation;

ice

FIG. 3 is an elevational view of the ski-bob shown in FIG. 2, with a depression between undulations being traversed at the point when the ski-bob is disposed centrally thereover;

FIG. 4 is a development view showing the leaf spring part of the lower rear frame, together with the yoke of the lower shock absorber in their relationships for assembly to the rear ski runner;

FIG. 5 is an enlarged, longitudinal, sectional elevational view of details of the pivotal connection of the lower part of the forward frame to the lower part of steering post, and of steering post lower part pivotal connection by leaf spring to forward ski runner;

FIG. 6 is an elevational view of a modification of the ski-bob shown in FIGS. 2 and 3, and which is illustrative of selective seat adjustment;

FIG. 7 is an enlarged elevational view of the yeildable connection construction between lower end of forward frame part and leading part of rear ski runner, such construction being shown in smaller scale in FIG. 6;

FIG. 8 is an elevational view of another modification of the ski-bob shown in FIGS. 2 and 3, in which an elastic cord establishes yieldable relationship between frame and rear ski runner;

FIG. 9 is an elevational view of an alternate construction for establishing yieldable relationship between frame and rear ski runner;

FIG. 10 is an elevational view of still another arrangement by which elastic cords establish yieldable relationship between frame and rear ski runner;

FIG. 11 is an enlarged detailed sectional elevational view of the shock absorber connection shown to smaller scale in FIGS. 8, 9 and 10, between rear end of seat and rear ski runner;

FIG. 12 is an enlarged detailed, transverse sectional elevational view taken along line 12-12 of FIG. 11;

FIG. 13 is a sectional elevational view of the housed spring connection, as shown in smaller scale between leading part of rear ski runner, and upper central frame parts, in FIG. 9; and

FIG. 14 is a longitudinal elevational view showing an alternative arrangement for yieldable connection frame and shock absorber to rear ski runner.

Beginning about 1891 in America, a ski-runner was first substituted for the front wheel of a bicycle with vertical supporters for sled-runners being attached on each side of the back axle, to comprise a snow bicycle, see US. Pat. No. 473,434, for Ice-Velocipede. Similar vehicles appeared in America and Europe about the turn of the century, termed single-track guidable sleds. By 1910 the Swiss Mongoleit was developed, but only usable on steep snow-tracks or channels with long runs. A primitive Skivelon followed, used mostly by bakers-apprentices and mailmen in the Grindlewald. By 1950 a much lower ski-bob type was in use in Bavaria with no wheels or sled-runners, but with front and rear ski runners connected to an oval frame, the riders feet being encased in separate foot attachments so heels can be applied to brake speed on inclines.

In the modern forms of ski-bobs, which are currently of widely increasing popularity, persons of all ages may participate in their usage. They are less dangerous and can be safely enjoyed, not necessarily by persons of strength and of athletic prowess, but by those of average, or even lesser strength than the norm. Thus their appeal tends to be more universal than the conventional ice skis, conventionally associated with skilled athletes, and compentitive ice field events.

There still be be said to exist an objection to conventional ski-bobs, as now developed, of the construction resulting in the front ski-runner being constantly disposed in substantially the same, substantially horizontal plane across, and including the line or path of travel. This objection results from the leading part of the rear skirunner being substantially rigidly, only slightly yieldably, connected to the forward arch of the frame of the vehicle (the steering post to the foot of which the forward skirunner is pivotally connected, having the foot of the steering post connected thereto).

Thus there is considerable distance along the path of the travel that the ski-bob ski-runners together extend in substantially rigid straight line projection. This results in the convention ski-bob, in passing over undulations in the path of travel, tending to tear u the undulations as its real ski-runner passes thereover, The herein forms of invention each sets out to provide a ski-bob with a substantially flexible or yieldable connection between the leading part of the rear ski-runner and frame, whereby the ski-bob may follow the contour of an undulation or depression, with the front ski-runner being advancing upwardly while the rear ski-runner may be advancing downwardly or substantially on the level, or vice versa.

Referring now in detail to the drawings in which like reference numerals are applied to like elements in the various views, a ski-bob is shown in FIG. 1 which discloses a generally informative form of the instant invention, as comprised of a frame 11, a steering post 16 with a leaf spring foot 13 about a pivot 40 which extends transversely of the path of travel, as provided by a bracket 23 on the forward ski runner 24, disposed intermediate the toe or bow 24a and the rear or heel 24b of the ski runner 24.

The steering post 16 has a cross-member 17 connected symmetrically across the top thereof to provide the handle bars, with grasps 18a and 18b for the hands of the rider. The upper pivotal connection between steering post 16 and the forward arch 12a of the frame 11 is provided by an upper pivot by a pivot bolt 19 between a plate 20 extending forwardly from the central frame part 1212, and an upper clip angle 21 on the rear face of the steering post 16 The lower pivotal connection, in line with the upper pivotal connection 19, is provided by a pivot end 14 on the lower end of the forward frame arch 12a, extending into a bore 15a in a lower clip angle 15 on the rear face of the steering post 16.

The frame 11 includes a rearwardly arched part 12c, extending rearwardly and downwardly from the central frame part 12b, terminating in a leaf spring transversely supported across the rear ski runner 31 by a rear support, pivot bracket 23a. The support bracket 23a is disposed upon the rear ski runner 31 intermediate the heel 31b and the leading part or toe 31a. The leading part 31a is shown connected to a hook 32, provided on the rear face of the lower part of the forward arched frame part 12a, by a connector part 310, that has its forward end hooked over the hook 32 and its rear part connected to the forward end of the leading part 31a by wire or strong elastic connection rings 33, whereby a yieldable or flexible connection is formed between the rear ski runner leading part 31a and the lower end of the arched frame part 12a. Thus it can be seen that, as travelling along a path or ice track, the forward ski runner 24 may be advancing on the level or upwardly, whereas the rear ski runner 31 may be advancing downwardly or on the level, or vice versa.

The seat 22 on which the rider sits is shown in FIG. 1 as being provided with a clip angle or connection lug 26 to extend below the forward part of the seat to be adjustably connected in selective longitudinally spaced apart positions with relation to a slot 26a in the frame part 1211. Beneath the rear portion of the seat 22, a supporting shock absorber has its upper end conventionally pivotally connected. The shock absorber 25 is indicated of conventional design, with a spring, not shown, being compressed between the two inter-telescoped upper 4 and lower

tubular members

28, 29 of the shock absorber 25.

As shown in FIGS. 2 and 3, a ski-bob 10', constructed generally after the manner of the ski-bob 10' shown in FIG. 1, is respectively, in transit over an undulation 27 in an ice track, between two depressions 57, or in transit over a depression 57 between two undulations 27. In the first case the forward ski runner 24 is shown advancing on a downward slope 27a while the rear ski runner 31 is shown advancing on an upward slope 27b. In the second case the forward ski runner 24 is shown advancing on an upward slope 27b while the rear ski runner 31 is shown advancing on a downward slope 27a. In case the track, trail or path of travel deviates from a straight course, or winds in plan view or upon the ground, since the steering post 16 is pivotal with relation to the frame 11, the ski-bob may be steered to keep the front or forward ski-runner 24 pointed generally with a curve in the path, while the rear ski runner 31 follows the direction of the path preceding the curve. Also, as to the ability of the ski-bob to follow undulations by virtue of the type of connection 31a and raised leading part 31a between the track contacting portions 31, 31b of the rear ski runner 31, and the forwardly arched frame part 12a, a part of the general path of travel may be generally tracked by the forward ski runner 24, as sloped in one direction while a part of the general path of travel to the rear thereof may be generally tracked by the rear ski runner parts 31, 3112.

This results, as may be observed from a consideration of FIGS. 2 and 3, since the angle between steering post 16 and forward ski runner 24 and the angle between the rearwardly arched frame part 120, and the rear ski runner parts 31, 31b may vary independently of each other. Thus, in passing over any undulation, there is a much shorter in line extension of ski runner to be topping and in part tearing up the crest of an undulation 27, or tearing it away by side swing, than in the case of conventional types of ski-bob hereinabove described, with the leading part of the rear ski runner substantially rigidly connected to the forwardly arched part of the frame.

As shown in detail in FIG. 4, the lower tubular member 29 of the

inter-telescoping members

28, 29 comprising the shock absorber 25, FIG. 1, terminates in a yoke 30 with bifurcations 30a, 30b, which may be disposed just outwardly of the re-curved or socket providing end of the rear leaf spring 13, which, as aforesaid, comprises the lower end of the rearwardly arched frame part 120. Thus, the pivot bolt a may be passed first through a part of the support bracket 23a, through a bifurcation 30b, through the recurved leaf spring end 35 on the pad 34 disposed on base 36 upon the ski-runner 31, thence through the other bifurcation 30a, and finally through the other part of the support bracket 23a. By this construction, in addition to being mounted to pivot on a transverse pivot, or to swing in a substantially vertical plane, with relation to the rear ski runner 31, the frame 11 is in degree yieldably or flexibly connected to the rear ski runner 31.

Referring now to FIG. 5, the pivotal connection between the frame 11 and steering post 16, FIG. 1, and also the pivotal connection between the lower leaf spring end 13 of the steering post 16, may be seen in detail. Thus the frame 11 may swing or pivot about an upwardly extending pivot axis 14, 19', with relation to the steering post 16 and forward ski runner 24, and also the steering post 16 and forward ski runner 24 may swing or pivot with relation to each other about an axis transverse to the path of travel, and generally in a substantially vertical- 1y extending plane. In this construction pivot end 14 at the lower end of the forwardly arched frame part 12a of the frame 11 comprises upwardly a block of rubber or resilient material 14d, which extends upwardly into the lower end of the box section type frame member 12a, and which is aflixed thereto by nuts and bolts 39c, 39d.

At the lower end of the rubber block 14d, below the lower end of the frame part 12a, a metallic flange 14c has the rubber block 14d firmly afiixed to the upper surface thereof, while a metallic post or pivot core 14a extends centrally downwardly from the flange 14c and below the level of the upper leg of the aforesaid clip angle 15. A rubber or resilient sheath member 14b has a flanged head to fit between the metallic flange 14c and the upper surface of the upper leg of the clip angle 15, while a shank part extends centrally downwardly from the flange part of the sheath member 14b, and through a bore in the upper leg of the clip angle 15. The sheath member 14b is bored centrally to receive the metallic shank or pivot core 14a therethrough. By this construction the frame 11 has the lower member 14 of its pivot axis with relation to the steering post 16, also yieldably or flexibly disposed in degree with relation to the steering post 16.

A block 37 of resilient material, as rubber, is shown with upper part inserted in the lower end of the steering post 16, and with the upper portion of the forward leaf spring 13 extending upwardly centrally through, or embedded in the rubber block 37, including a base part 37a provided below the lower end of the steering post 16. The leaf spring 13 extends upwardly within the lower end of the steering post 16 to terminate in a recurved or rounded upper end 38 formed to bear with spring pressure upon the inner, forward and rear surfaces of the box type section steering post 16. Nuts and

bolts

39a, 3% are additionally provided, firmly to connect the block 37 and lower end of the steering post 16.

From the block base 37a the leaf spring 13 curves downwardly and forwardly to terminate in a recurved or socket providing, forward end 35. Thus, a pivot bolt 40 may extend through a part of the bracket 23, and through the leaf spring pivot socket 35, as supported upon a pad 34 upon a base 36 connected to the forward ski runner 24, by screws or bolts, not shown, and then through the other part of the bracket 23.

As shown in FIG. 6, a modification of the form of invention shown in FIGS. l-5, discloses a frame 11 with rearwardly arched part 110 separately pivotally connected, without leaf spring, to a rear support bracket 23a, from the pivotal connection of the shock absorber 25 thereto, the shock absorber 25 being shown substantially diagrammatically. Forwardly of the upper, central section 11b of the frame 11, the forwardly arched frame part 11a is pivotally connected to pivot about a substantially

upstanding axis

14, 19, with relation to the steering post 16, correspondingly as hereinabove described in regard to FIGS. 1-5. Also, the steering post 16 has a leaf spring 13 on its lower end by which it is connected to pivot about a transverse pivot 40, comprising a transverse pivot axis, so that the steering post 16 and frame 11 con nected thereto, can pivot in a substantially vertical plane with relation to the forward ski runner 24, correspond ingly as shown in FIGS. 1-5.

The seat 22 is shown provided with a clip angle or lug 26a to extend therebelow to be selectively connected to the frame part 11b by means of nuts and bolts passed through longitudinally spaced apart holes 42a in a spine or plate 42 disposed centrally on top of the central frame part 11b. The upper end of the shock absorber 25 is pivotally connected by means of a conventional transverse pivot providing arrangement, not shown, to the under side of the seat 22. Thus the seat 22 may be adjusted within range from full line to dotted line position shown in FIG. 6.

As shown in FIG. 7, the leading part 41a of the rear ski runner 41 has a wing bolt 41d in the nose or forward end thereof so that the rear loop of an elastic cord 42 may be hooked thereunder, the ends of the cord 42 being firmly sewed and connected together, as by strong threads 43. The forward loop of the cord 42 is looped over a hood 32a that is provided on the rear face of the forwardly arched frame part 11a. Thus, as best indicated in FIG. 6*, the elastic cord 42 comprises a resistably yieldable, flexible connection between rear ski runner 41 and frame 11 of the ski-bob 10a.

Making reference now to FIG. 8, a ski-bob 10b is shown that differs in one particular form preceding structures in that the steering post 16a has no leaf spring lowermost, but makes a plain pivotal connection with the forward ski runner 24 by means of a transverse pivot bolt 40a which connects it to a bracket 23d supported by the ski runner 24 just forward of its heel 24b. As an additional variation the lower parts of the rearwardly arch'ed frame part 11c and of a shock absorber 50 are connected, successively, to forward and rear pivots provided by a bracket 23b supported upon the rear ski runner 41 between the heel 41b and leading part 410 thereof. The shock absorber 50, to be hereinbelow described in detail, is shown including an upper tubular member 46a and a lower tubular member 46b terminating downwardly in a rod or cylindrical member 47 (by which pivotal connection is made to the aforesaid bracket 23b). The upper end of the shock absorber upper member 46a provides a transverse pivot axis, not shown, to which is connected a connector beneath the rear part of the seat 22. Also, a clamp 26b is provided by which the forward end of the seat 22 is adjustably connected to the central frame part or saddle 11b.

Also, in variation, an elastic cord 44 extends from a lug 230 on the upper, forward corner of the bracket 23b, through a guide opening 51 in the leading part 410 of the rear ski runner 41, to a connection ring 45 which extends rearwardly from the lower end portion of the forwardly arched frame part 11a.

The elastic cord 44 must be of substantial strength and of predetermined limited elasticity, as it has to restrain the rear ski runner 41 to maintain continuing contact with the ice or track over the length of the central and heel part 41b thereof, and thus must resist the tendency of the leading part 410 to kick upwardly responsive to bumps or irregularities in elevation occurring in the track.

Now considering FIG. 9, the ski-bob has a rearwardly arched frame part and shock absorber 50, to be hereinbelow described in detail, which are connected to a bracket 23a upon the ski runner 41, correspondingly as hereinabove described in connection with the similar relationship of these elements in FIG. 8. However, it may be seen that the leading part 41d is connected to the frame 11 in an entirely different manner, and in an entirely different direction, than hereinabove described in regard to the rear ski runner leading parts 31a, 41a and 410 of the forms of invention shown in FIGS. 15, in FIGS. 6-7, and in FIG. 8. Thus in this construction, a spring loaded connector 60 is shown having its lower member 60b pivotally connected to a bracket 57b mounted on the upper surface of the leading part 41d. Upwardly, the upper end of the connector upper member or cylinder 60a is pivotally connected to a bracket 57a provided on the under side of the frame central part or saddle 11b forwardly of the saddle 22.

In this construction the spring, not shown in FIG. 9, may constantly urge downwardly thus to constrain the leading part 41d of the rear ski runner 41 from flying upwardly responsive to any undulations or irregularities in elevation along the path of travel or ice track. This can be an important feature except that some large object or obstruction that could become insinuated between the forwardly arched frame 11a and the leading part 41d of the rear ski runner 41, would have to be broken up or pushed aside by the rear ski runner 41.

Referring now to FIG. 10, still another variation of skibob 10d is disclosed in which the hold-down cord 44 and shock absorber 50 are employed as hereinabove described with relation to the form of invention shown in FIG. 8.

Additionally an elastic cord 44a is disposed to extend resiliently yieldably and flexibly between a bracket 48b on the upper surface of the rear ski runner leading part 410 and a bracket 48a on the under side of the central frame part or saddle 11b. Also, another elastic cord 44!) is shown extending between a bracket 49a on the upper rear part of the rearwardly arched frame part 11C and a bracket 4912 on the upper surface of the heel 41b of the rear ski runner 41. Optionally, in place of the elastic cords 44a and 441) spring loaded connectors 60- may be mounted to extend in corresponding directions.

With this form invention the service exacted from the .elastic cord 44 is particularized by counterpoising the forward and rear counterbalancing cords 44a, 44b in part against each other. The rear cord 44!), in pulling upwardly on the rear ski heel 41b, tends to pivot the leading part 41c downwardly, about the pivotal connection of the frame part 11c and rear ski runner 41 at the bracket 23b. Conversely, the forward cord 44a, in pulling upwardly on the rear ski leading part 410, tends to pivot the heel 41b downwardly about the pivotal connection of the frame part 11c and rear ski runner 41 at the bracket 23b. If spring loaded connectors 60 are employed in place of the COIdS 44a, 44b, the direction of urging is opposite- 1y, but the counterpoising of elements that effectuate at least partial counterbalancing is the same. Thus, the cord 44 action is calibrated for its hold-down erect, after taking into consideration the degree of counterbalancing brought about, as hereinabove described.

The shock absorber 50, indicated partially diagrammatically, as provided between rear end of seat 22 and rear ski runner 41 in FIGS. 8, 9 and 10, is shown in detail in FIGS. 11 and 12. The upper member 46a is pivotally connected to a connection tube 63 which extends downwardly within the rear, under portion of the seat 22, a transversely extending bolt 54 passing through the tubing 63 from left to right, while the connection tube or tubing 63 may pivot fore and aft with relation to the upper tubular member or cylinder 46a and about the pivot bolt 54. Thus, the tube 53 extends within a slot 52a in a metal block 52 in the upper end of the cylinder 45a, the metal block 52 being fixed in top of the cylinder 46a, right under the top closure 46b thereof, by means of the transverse pivot bolt 54 passing therethrough on either side of, and outwardly of the connection tubing 63.

The lower member or rod 47 of the shock absorber 50 is indicated in FIGS. 8, 9 and as having its lower end pivotally connected to a transverse pivot supported by the bracket provided just forward of the heel 41b of the rear ski runner 41. At its upper end the rod 47 is rigidly connected into a base flange 47a in which seats the lower end of a lower cylindrical member 46b with upper end of dimension to telescope within the upper cylindrical member 46a. A transverse bolt 55b extends across, and connects the base flange 47a and the cylinder 46b. Above the base flange 47a the lower cylindrical member 46b has left and right slots 56a, 56b therein which extend upwardly for substantial distance, with the lower end of the upper cylindrical member 46a occluding the upper ends of the slots 56a, 56b for some distance. A bolt 55a extends across the lower end of the upper cylindrical member 46a and through the slots 56a, 56b just inwardly thereof.

Also a head 50a is insertable into the upper end of the lower tubular member of cylinder 4612, the head 50a having a bore 50b centrally therethrough. A transverse bore is provided through the head 50a above the top of the tubular member 461) and a connection pin 53 is inserted through the bore 50b to extend altogether within the head 50a and across the central bore 5%. An elastic cord 540 extends resistably yieldably and flexibly between, and around the bolts 55a, 5512. Also two

elastic cords

54a, 54b extend resistably yieldably and flexibly between, and around the pin 53 and bolt 55a, the elastic cord 54c being 8 disposed upon the bolt 55a between the

elastic cords

54a, 54b.

Any extra force or weight distribution on the seat 22 that may result in downward urge on the upper tubular member 46a moves the bolt 55a nearer the bolt 551;, so that the elastic cord 540 is permitted to contract, with resultant stretch of the

elastic cords

54a, 54b as they yieldably resist the bolt 55a moving away from the cross pin 53. Or conversely, any separative force or tendency of the upper cylindrical or tubular member 46a to slide upwardly with relation to the lower tubular member 461), results in the contraction of the two

upper cords

54a, 54b, and in the expansion or stretch of the lower cord 540. Thus, by properly sizing the

cords

54a, 54b and 540, wit-h proper distance between cross-pin 53 and bolt 55b and with the proper predetermined occlusion of the slots 56a, 56b by the upper tubular member 46a, it is possible to provide a shock absorber 50* that will properly respond to shock in both direction.

A spring-loaded connection member 60, shown in FIG. 9, may be described in detail in relationship to FIG. 13; the shock-absorber 25 shown in FIGS. 1-3 and in FIG. 6 being similarly constructed. Thus a bracket 57b mounted on the forward upper surface of the leading part 41d of the rear ski runner 41 may have the lower or rod member 6011 pivotally connected thereto, as by a pivot pin c passed through the bracket 57b and through the rod member lower end 5817. The rod 6% extends upwardly into the upper tubular member or cylinder 60, and has a head or piston 59 on the upper end thereof, with an O-ring 59a therearound to bear yieldably sealably upon the inner surface of the cylinder 60a. Above the piston or head 59 a spring 61 has upper end to bear upon an inner boss 58b comprising part of an upper closure 58a, for the cylinder or upper member 60a. The spring 61 is thus enclosed between the piston head 59 and upper closure 58a, constantly to bear resistably, yieldably against the piston head 59. A bracket 57a is mounted on the under side of the central frame part 16b and the closure lug or cylinder top member 58a and this bracket 57a are relatively pivotally connected about a transverse pivot bolt 57b shown in FIG. 13. A lower closure 60d receives the piston rod 60b therethrough and closes the lower end of the cylinder 60a. Thus the lower closure 60d may act as a stop against the spring 61 urging the piston 59 out of the cylinder 6011 when frame and rear ski runner tend to be spread farthest apart.

In FIG. 14 a variation of yieldable or flexible connection between the rearwardly arched frame part 110 and ski runner 31 is shown of a type to be used in place of the form of connection shown in FIG. 4, and this form has additional advantage in that the lower end of the shock-absorber between seat and rear ski runner may also be yieldably or flexibly connected. Refer to FIG. 4 where a rigid yoke makes connection.

In the form of connection shown in FIG. 1 a leaf spring 62 has its forward end 63a affixed to the upper surface of the rear ski runner 31, as by a screw or screws 64. The leaf spring 62 is formed and tempered normally to provide the degree of arch for normal operating conditions. A lug or plate 63 upstands centrally from the top of the leaf spring arch and the rearwardly arched frame part 116, terminating in a foot part 290, may be pivotally connected to the forward part of the lug 63, as by a conventional pivot pin. Also, the shock-absorber 25a, below the skibob seat, may provide a foot part 29b at the lower end of the lower shockabsorber member 29a which may be pivotally connected to the rear part of the plate or lug 63 by a conventional pivot pin. Rearwardly of the leaf spring arch the leaf spring is flattened with rear portion 63b to slide through a keeper or hold-down plate 65 installed across the leaf spring on the heel 31b of the rear ski runner 31.

Thus, when frame and rear ski runner 31 tend to draw apart in service, as on an ice track, the leaf spring arches further upwardly as its rear portion 63b slides forwardly in the keeper plate 65. Or, when the frame and rear ski 4 runner 31 tend to draw closer together in service, the leaf spring arch is flattened as the leaf spring rear portion 63b slides rearwardly in the keeper plate 65. Under the above usages, the shock-absorber lower member 29a thus moves with the leaf spring arch in accordance with the respective conditions set forth. It should be pointed out that a corresponding arched leaf spring connection may be employed between steering post and forward ski runner in place of the type of leaf spring connection 13 shown in detail in FIG. 5.

The various separate features as to connection between steering post and forward ski runner, connection between rear ski runner leading part and frame, connection between frame and rear ski runner, shock-absorber construction and connection, and rear ski runner hold-down and counter-balancing, may be used interchangeably and in various combinations, all falling within the spirit of the invention, which is further presented in the appended claims.

What is claimed is:

1. A ski-bob comprising a frame with an integrally formed forwardly and downwardly extending forward part, an upper central saddle part with a seat thereon and a rearwardly and downwardly extending rear part, a forward ski runner with an upwardly turned leading part, a steering post pivotally connected to said frame forward part and having a lower end portion means pivotally connecting said forward ski runner to said steering post lower end portion so that it is relatively pivotal thereon in an upright plane that extends through said steering post and said forward ski runner, a rear ski runner positioned longitudinally in line behind said front ski runner and having an upwardly turned leading part, means located to the rear of its said leading part pivotally connecting said rear ski to said frame rear part so that said rear ski runner is movable relative to said frame in an upright plane that extends through said frame and said rear ski runner, and resiliently extensible means yieldably connecting said rear ski runner leading part to said forward frame part, whereby said ski-bob in transit may closely follow a track that may be undulatory in elevation and curved in plan view.

2. A ski-bob as claimed in claim 1 wherein said resiliently extensible means yieldably connecting said rear ski runner leading part to said frame comprises an elastic cord between said leading part and said frame forward part.

3. A ski-bob as claimed in claim 1 wherein said resiliently extensible means yieldably connecting said rear ski runner leading part to said frame comprises an intertelescoping, coil spring enclosing, tubular assembly.

4. A ski-bob as claimed in claim 1 wherein said resiliently extensible means yieldably connecting said rear ski runner leading part to said frame comprises an elastic cord having a rear end supported on said frame above said rear ski runner rearwardly of said leading part, and passing forwardly through the upper portion of said leading part and a front end connected forwardly to the lower portion of said frame forward part.

5. A ski-bob as claimed in claim 4 which additionally includes elastic cords in counterpoised relationship between the leading part of said rear ski runner and said saddle part and between the rear portson of said rear ski runner and said frame rear part.

6. A ski-bob as claimed in claim 1 wherein said means for pivotally connecting the lower end of said steering post to said forward ski runner includes a yieldable leaf spring.

7. A ski-bob as claimed in claim 6 wherein said leaf spring is curved and has an upper end portion fixed to said steering post and a lower end portion pivotally connected to said forward ski runner.

8. A ski-bob as claimed in claim 1 wherein said means connecting the frame rear part to said rear ski runnecomprises a leaf spring having an upwardly arched por tion fixed to said rear frame part.

9. A ski-bob as claimed in claim 1 including a shockabsorber interconnecting the rear portion of said seat and said rear ski runner adjacent a said frame rear part, said shock-absorber being comprised of upper and lower, inter-telescoping tubular members connected by upper and lower elastic cord means, whereby upper elastic cord means stretch upon downward movement of said upper tubular member, and lower elastic cord means stretch upon upward movement of said upper tubular means.

References Cited UNITED STATES PATENTS 1,516,941 11/1924 Winn 280' 16 2,17 6,397 10/ 1939 Flanders 280-16 2,354,627 7/ 1944 Wheeler 2-80--16 2,479,674 8/ 1949 Elliot 280-16 FOREIGN PATENTS 385,637 3 1965 Switzerland.

87,487 7/ 1966 France. 443,931 2/ 1968 Switzerland.

LEO FRIAGLIA, Primary Examiner R. R. SONG, Assistant Examiner