BACKGROUND OF THE INVENTIONThis invention lies in the field of bindings for snow skis and is directed to apparatus for facilitating the attachment of skis to ski boots. It is more particularly directed to apparatus for pre-loading the latch means of the binding and restraining it until the boot is set in position and releasing it to snap into latching position.
Since skiing has become increasingly popular throughout the world, many different types of ski bindings have been proposed and put into use. Early bindings were simple straplike devices which provided a rather unreliable connection between boot and ski with frequent separation on bumps and hard turns. Such bindings were gradually improved until the connection was adequately secure. However, this raised a different problem. In the event of a fall, the skis would not release and tangling of the skis and digging into the snow frequently caused severe leg and ankle injuries.
This problem was overcome by the modern types of releasable heel and toe bindings in which the toe of the boot fits into a toe cap and the heel is clamped by a latch which is spring pressed against the boot heel or some abutment attached to it. The force of the spring pressure is adjustable to accommodate skiers of different weights and skills. The spring load is sufficient to prevent separation during normal maneuvers but yields to the excessive force generated in a fall and releases the ski. Another type achieves the same general results but utilizes side clamps swinging laterally to grip the side edges of a plate attached to the sole of the boot. Usually the loading spring or force unit is located just behind the aft end of the boot. Since it must be adjusted from no-load to loading condition after the boot is in position the skier must stoop and bend awkwardly to reach the unit and adjust it. This is not too difficult at a suitable location at the top of a slope but when a skier has fallen in mid slope and is replacing his skis while attempting to maintain his balance on a steep incline it becomes very difficult.
Several heel and toe types bindings have been proposed which permit a skier to step into the binding and cause it to clamp automatically by forcing a lever on the apparatus to lower under the boot heel and cause the entire mechanism to swing against an over center spring arrangement. This requires an undesirably high degree of force to be exerted when the skier is in a delicately balanced position, and it also calls for a multitude of links, levers, cams and springs, all of which adds to the cost and likelihood of damage or failure.
SUMMARY OF THE INVENTIONThe device of the present invention overcomes the difficulties mentioned above and provides a simple and reliable means to provide snap lock actuation of a ski binding and obviate the need for stooping and bending in the process of attachment. While the device was developed for a particular one of the types mentioned above, its principles may be incorporated in almost any type of spring loaded binding.
Generally stated the invention is incorporated in a binding which includes a substantially rigid latch receiving member provided with at least one latch receiver formation and a substantially rigid latch mounting body. A pair of latch means are carried by the body to move laterally to engage the latch receiver formation. A resilient force unit is carried by the body and is adjustable between a no-load condition and a loading condition and it is connected to the latch means by link means to transmit the urging of the force unit to the latch means on occasion. A binding of this type is disclosed in U.S. Pat. No. 3,606,370 issued to Richard G. Spademan Sept. 20, 1971.
A detent trigger is mounted on the body and is movable between a first interfering position and a second non-interfering position. It includes a detent portion and a contact portion and when it is in the first position the detent portion engages the link means to prevent it from moving to latching position. It is spring biased to automatically move into this interfering position when the force unit is ajusted to no-load condition, after which the force unit is again adjusted to loading condition. At this time the contact portion is exposed and is actuated by the skier upon placing his boot on the ski in skiing position to withdraw the detent portion and allow the latch means to snap into engagement with the latch receiver formation.
In a preferred form the latch mounting body includes a sole plate having a recess in its under side extending in a fore and aft direction and the link means is an elongate link slidably mounted in the recess and having an elongate longitudinal slot therethrough from top to bottom. The forward portion of the link engages the latch means to move them laterally in and out, and the aft end of the link is connected to the force unit. An aperture is formed in the sole plate directly above the slot. The trigger includes a contact portion vertically movable in the slot and the aperture and a detent portion at the lower end of the contact portion extending forwardly and slidable vertically into and below the slot. When the force unit is in no-load condition a spring pushes the detent portion up into the slot with its forward end in contact with the forward end of the slot, and the contact portion extends above the upper surface of the sole plate. The force unit is again adjusted to loading condition and the apparatus is ready to be secured. When the skier places his boot in skiing position and applies his weight, the boot sole presses the contact portion down and the detent is lowered out of the slot. The link is released and moves rearward in response to the force of the force unit, moving the latch means into latching engagement. The detent trigger does not in any way interfere with the normal automatic releasing action of the binding.
BRIEF DESCRIPTION OF THE DRAWINGSVarious other advantages and features of novelty will become apparent as the description proceeds in conjunction with the accompanying drawings, in which:
FIG. 1 is a perspective view of the total binding assembly with the ski boot about to be secured in place;
FIG. 2 is an inverted exploded view in perspective of the latching component of the binding;
FIG. 3 is a bottom plan view of the latching component;
FIG. 4 is a sectional view taken on line 4--4 of FIG. 3;
FIG. 5 is a sectional view taken on line 5--5 of FIG. 3;
FIG. 6 is a sectional view taken on line 6--6 of FIG. 1 showing the linkage in restrained condition and the boot just above the trigger; and
FIG. 7 is a view similar to FIG. 6 with the linkage released and the boot secure.
DESCRIPTION OF PREFERRED EMBODIMENTSThe ski binding incorporating the features of the invention is generally illustrated in FIG. 1, in which alatch mounting body 10 is carried by aski 12. The body includes an aft heel stop andcamming section 14 and a forwardly extendingsection 16 comprising a sole plate which is fixedly secured to the ski by screws 18. Theaft section 14 includes two laterally spacedstandards 20, each of which has a forwardheel guiding surface 22 to assist in longitudinally locating the boot as it is placed in skiing position and upper andaft camming surfaces 24 to be used in loading theresilient force unit 26.Latch members 28 are movably mounted in the sole plate section of the body to move laterally in and out to secure or release theboot 30. Each boot is provided with a laterally extendingboot plate 32 secured to the boot by screws, not shown, and formed at its marginal edges with latch receiver formations 34 which are engaged and gripped by the latch means when they are moved inward.
The construction, mounting, and actuation of the latch means is illustrated in the inverted exploded view shown in FIG. 2. The under side of the sole plate is formed with a large recess 36 having an upright interruptedside wall 38. Each latch means 28 includes alever arm 40 with an aperture 42 at its aft end for pivotal mounting on apivot post 44 which has acentral aperture 60 for passage of one of the mounting screws 18. The forward portion of each arm extends outward and back in to define a generally U-shape in planform, providing webs 46 and 48 guided incutaway portions 50 and 52 inside wall 38, with anupstanding gripping jaw 54 formed at the base of each U. The inner ends of each U are formed withcam surfaces 56 and 58 which are angled inwardly and forwardly.
The link means connecting the force unit to latch means 28 comprises anelongate link 62 slidably mounted for fore and aft movement in longitudinal recess 64 which extends below the basic recess 36. The link is provided with anelongate slot 66 to fit over and be slidably guided by elongated guiding and mounting rib 68 which extends up from the bottom of recess 64, and is formed at its forward end with a T-shaped head 70 havingcam surfaces 72 and 74 at its outer ends which are angled inwardly and forwardly to mate with thecam surfaces 56 and 58 on the latch means. When the link moves forward it moves the latch means laterally outward and when it moves rearward it moves the latch means inward to engage formations 34 on theboot plate 32 and secure the boot to the ski. Acover plate 76 having anelongate aperture 78 near its forward end and twopilot apertures 80 at its aft end to fit ontopivot posts 44 seats withinside wall 38 to retain the latching components in working position. It in turn is held in its proper position by contact with the upper surface of the ski whenbody 10 is secured to the ski.
As seen in FIGS. 1 and 6, the aft end oflink 62 is provided with a pair of upstanding laterally spacedears 82 havingapertures 84 to receivepivot pin 86. The force unit includes anelongate shank 88 pivotally mounted at its forward end onpin 86 and bearing threads on its aft end. A cup-shapedwasher 90 is slidably mounted on the shank and receives the forward end ofcompression coil spring 92. Nut 94 is threaded on the aft end of the shank and may be adjusted to produce any desired degree of compression in the spring. A conventional bail 96 is pivotally connected to the standards at 98 to serve as an anchorage for a safety retriever line.
In the absence of the device of the present invention a skiier would adjust nut 94 to predetermined point which would provide the desired degree of compression, with the force unit in the position indicated by the broken lines in FIG. 6.Link 62 would be in its forward, or free, position and the spring would be substantially under no compression withwasher 90 resting on upper camming surfaces 24. The skiier would place his boot on the sole plate and then swing the force unit down to the horizontal position. Since thelower camming surface 24 is at a greater distance frompivot point 86 than is the upper camming surface, thewasher 90 would force rearwardly and compressspring 92, which would normally pulllink 62 rearward to the position shown in FIG. 7, and the engagement of cam surface 72 withcam surface 56 would forcegripping jaws 54 inward into latching engagement with the receiver formations 34.
Returning to FIG. 2, thedetent trigger 100 comprises a vertically directedcontact portion 102 and a horizontally forwardly directeddetent portion 104 connected to the lower end of the contact portion. The contact portion extends upwardly through theaperture 106 in the sole plate as seen in FIGS. 1, 5, and 6 and is vertically slidable therein, while the detent portion is movable vertically into and out of the forward portion ofslot 66 inlink 62 as can be seen in FIGS. 6 and 7. Aleaf spring 108 is mounted on rib 68 by means of ascrew 110 threaded into bore 112, and its forward forkedend 114 straddlesboss 116 of the sole plate to prevent lateral rotation. Withcover plate 76 in place andbody 10 secured to the ski,spring 108 is fixedly supported at its aft end and slidably supported at itsforward end 114 and directly underliesdetent portion 104. Its normally flat form yieldingly urges the trigger toward its upper position.
To operate the securing mechanism in accordance with the invention the force unit is swung upward to the broken line position shown in FIG. 6 withwasher 90 resting on upper camming surfaces 24 and nut 94 properly adjusted but exerting substantially no compressive force on the spring at the moment.Link 62 is moved to its foremost free position andspring 104 pushes the trigger upward so that theupper end 118 of thecontact portion 102 extends above the surface of the sole plate and the detent portion slides upward into the forward portion ofslot 66 with itsforward end 120 engaging theforward end 122 of the slot in interfering position to restrain the link against rearward motion to a latching position. Theforce unit 26 is then pushed downward and rearward to the solid line position shown in FIG. 6, the lower cammingsurfaces forcing washer 90 rearward and compressingspring 92 to loading condition so that the latch means is in effect cocked. This pre-setting can be accomplished with the ski held in the hand or lying free on the ground without the necessity for the skiier to stand with his boot in place on the ski and awkwardly twist and bend to activate the force unit.
After the mechanism is cocked the skiier lowers his boot into the position shown in FIG. 6 with the aft end in contact with heel guiding surfaces 22 and with the boot plate on theupper end 118 ofcontact portion 102. The spring loaded contact of the slot with the detent portion resists movement of the trigger under relatively low forces and prevents inadvertent actuation of the mechanism. When the boot is properly located in skiing position the skiier applies his weight and the boot plate forces the trigger down and moves the detent portion out ofslot 66 and thus out of interfering position. The force unit snaps the link rearward which swings the latch means inward into latching engagement with receiver formations 34. The latching position is indicated in FIG. 7. It will be apparent that when the trigger is in non-interfering position the binding is free to operate in its normal manner including the function of automatically releasing the ski in response to the excessive forces of a fall.
It will be seen that the apparatus described above and illustrated in the drawings provides a very simple and easy means for accomplishing step-in latching at an extremely low cost and with no maintenance problems. The principles of construction and operation have been shown in connection with a particular type of binding but it will be obvious that they may be incorporated in many other types and variations without departing from the spirit of the invention.