United States Patent Schriewer [4 1 Jan. 18, 1972 [541 SAFETY TOE IRON FOR SKI BINDINGS Primaiw Examiner-hee Fiieglie Assistant Examiner-Robert R. Song [72] Inventor: Ernst-Richard Schriewer, Garmisch-Parm 1: Gipple and Jacobson tenkirchen, Germany [73] Assignee: Hannes Marker, Garmisch-Partenkirchen, [57] ABSTRACT Germany The toe iron is laterally pivotally movable in response to an excessive tor ue and comprises a ivoted member, which is [22] Ffled' 1970 pivoted on g pivot pin, which is fim sly connected to the ski and [21] Appl. No.: 8,974 extends at right angles to the surfaces of the ski, and a soleholder, which is pivoted to the pivoted member by means of a second ivot in, which is at ri ht an les to the surface of [30] Fore'gn Apphcatlon Pnonty Data the ski. The toe i on also comprisis at liast one ball detent Feb. 10, 1969 Germany ..P 19 06 569.1 device, which is biased by spring pressure and disposed between the pivoted member and a baseplate, which is fixed to [52] U.S.Cl ..280/11.35T the ski. The pivoted member comprises a bipartite housing, [51] Int. Cl. ..A63c 9/08 containing in its interior a prestresised spring element which {58] Field of Search .280/ 11.35 T acts on the detent ball or balls and on the soleholder. The spring element consists of a helical compression spring, which 5 6] References Cited in known manner bears on a sheet metal abutment. The sheet metal abutment has a vertical flange, which lies opposite to UNITED STATES PATENTS the soleholder and extends transversely to the longitudinal direction of the housing, and the sheet metal abutment is 31333232 3232? fiiiififiiiiiiiiiiii: "31338313321 meieiie iii iiie ieiiieei eiieeiieii end in iiie ieiieieiiiiiiei 3292:941 12/1966 Berchtold et al ..280/] 1.35 T directb the housing and has a each deem ball.
3 Claims, 2 Drawing Figures PATENTEU JAN? 8 m2 RICHARD SCHRIEWER ATTORNEYS SAFETY TOE IRON FOR SKI BINDINGS The present invention relates to a safety toe iron for ski bindings, which toe iron is laterally pivotally movable in response to an excessive torque and comprises a pivoted member, which is pivoted on a pivot pin, which is firmly connected to the ski and extends at tight-angles to the surface of the ski, and a soleholder, which is pivoted to the pivoted member by means of a second pivot pin, which is at right-angles to the surface of the ski. The toe iron also comprises at least one ball detent device, which is biased by spring pressure and disposed between the pivoted member and a baseplate, fixed to the ski. The pivoted member consists of a bipartite housing, which contains in its interior a prestressed spring element which acts on the detent ball or balls and on the soleholder.
In known safety toe irons, the spring element consists of a block of rubber or elastomeric plastics material, and this block has a bottom surface which preferably by means of a sheet metal abutment cooperates with the detent ball whereas the rear end face of the block is at least in conforming engagement with an extension of the soleholder which extension protrudes forwardly beyond the second pivot pin.
Compared to other two-pivot safety toe irons the known safety toe iron has the advantage that only one spring element is required. That spring element produces the vertical spring pressure, which determines the torque required for a release of the toe iron, and the horizontal spring pressure, which tends to hold the soleholder in its central position or to return the deflected soleholder to that central position. As a result, the two-pivot safety toe iron is less expensive and can be manufactured at a lower cost than other known toe irons having two pivots.
Various inherent properties of the rubber have proved undesirable in the known toe iron having a rubber spring. The rubber is not age-resistant and does not enable an exact hardness setting. Besides, a large block is required to take up any forces which may occur. The hardness of the rubber changes also with temperature. The disadvantages which have been previously described are also involved in the use of the commercially available elastomeric plastics materials, which may be used instead of rubber.
It is an object of the present invention to provide a safety toe iron which eliminates the disadvantages of the known toe irons provided with a spring of rubber or plastics material,
In a safety toe iron for ski bindings, which tie iron is laterally pivotally movable in response to an excessive torque and comprises a pivoted member, which is pivoted on a pivot pin, which is firmly connected to the ski and extends at right angles to the surface of the ski, and a soleholder, which is pivoted to the pivoted member by means of a second-pivot pin, which is at right angles to the surface of the ski. The toe iron also comprises at least one ball detent device, which is biased by spring pressure and disposed between the pivoted member and a baseplate, which is fixed to the ski. The pivoted member comprises a bipartite housing, which contains in its interior a prestressed spring element which acts on the detent ball or balls and on the soleholder. The object is accomplished according to the invention in that the spring element consists of a helical compression spring, which in known manner bears on a sheet metal abutment having a vertical flange, which lies opposite to the soleholder and extends transversely to the longitudinal direction of the housing, and the sheet metal abutment is movable ifiihe vertical direction and in the longitudinal direction of the housing and has a runup ramp for each detent ball.
Whereas the toe iron according to the invention does not have a rubber spring which acts toward both sides, only a single helical compression spring is required so that the housing may be very small and the toe iron is particularly suitable for use on skis for children.
An embodiment of the safety toe iron according to the invention will now be fully described by way of example on the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a central longitudinal sectional view showing the toe iron and FIG. 2 is a top plan view showing the toe iron with the upper part of the housing and the helical compression spring omitted.
DETAILED DESCRIPTION OF THE DRAWINGS The safety toe iron according to the invention comprises a baseplate 1, which is adapted to be screw-connected to a ski. A vertical pivot pin 2 is riveted into the baseplate and has a screw-threaded free end portion. The lower part 3 of a twopart housing is rotatably mounted on the pivot pin. The housing serves as a pivoted member. The upper housing part 4 is fitted onto the lower housing part and is capable of a limited vertical displacement relative to the same. A withdrawal of the upper part 4 from the lower part 3 is prevented by a headed pin 5, which has a tapped hole and is screw-threaded onto the free end portion of the pivot pin 2. The head of the pin 5 has a slot, which can receive a screwdriver or coin for turning the pin 5. A second pivot pin 6 is rotatably and axially immovably mounted in the housing sections, 3 and 4, and just as the headed pin 5, has at its top end a slot for engagement by a screwdriver. The pin 6 has a screw-threaded central portion and carries a soleholder 7. A rotation of the pivot pin 6 will move the soleholder 7 up and down for adaptation to soles differingin thickness.
With reference to FIG. I, the lower part 3 of the housing which forms a pivoted member is formed with two holes, which are disposed on opposite sides of the pivot pin 2 and in which respective balls 8 are mounted, which formparts of respective ball detent devices. The detent sockets for the two balls consist of two holes 9 formed in the baseplate 1. A helical compression spring I0 is associated with both ball detent devices and by means of a sheet metal abutment Ill acts on the two balls 8 to hold the same in engagement with the detent sockets 9. The helical compression spring is mounted on the pivot pin 2 and the headed pin 5 and bears on the upper portion 4 of the housing. A rotation of the headed pin will result in a vertical movement of the upper housing part to vary the initial stress of the helical compression spring. The sheet metal abutment Ill has a vertical flange 12, which is opposite an extension 13 of the soleholder '7. The extension 13 extends beyond the pivot pin 6 into the interior of the housing. As is apparent from FIG. 2, the flange 12 extends transversely to the longitudinal direction of the housing. That surface of the extension I3 which is opposite the flange I2 is slightly concave so that it bears on the flange only at the two side edges of the extension when the soleholder is in its normal position. As a passage for the pivot pin 2, the sheet metal abutment ll has a slot 114, which extends in the longitudinal direction of the housing. Depending extensions 15 of the sheet metal abutment II are indicated in dotted lines in FIG. 2 and serve to locate said abutment relative to the lower part 3 of the housmg.
The sheet metal abutment II is vertically displaceable and the slot 14 permits a limited displacement of the sheet metal abutment ll in the longitudinal direction of the housing. The sheet metal abutment is formed with runup ramps for the two balls 8 so that it can be displaced in the longitudinal direction of the housing in the normal position. as shown in FIG. I, only against the force of the helical compression spring 10. A spacing washer I6 is mounted on the pivot pin 2 between the helical compression spring and the sheet metal abutment. The spacing washer l6 serves to minimize the friction and to prevent the helical compression spring from being carried along by the sheet metal abutment 111 during a movement of the latter.
In the normal position of the safety toe iron, the detent balls 8 are forced into the detent sockets 9 by the sheet metal abutment II, which is under the action of the prestressed helical compression spring 10, so that the housing 3 and 4 is held firmly in its central position. Cooperating with the runup ramps of the sheet metal abutment 11, the detent balls 8 hold the abutment in its right-hand end position in the figures of the drawing so that the soleholder 7 is held in its normal position at the same time. If the soleholder is subjected during skiing to a force which is transverse to the longitudinal direction of the ski and which is transverse to the leg of the skier, such force will produce a torque about the pivot pin 2 so that the resistance presented by the helical compression spring is overcome and the interlock between the housing and the baseplate is eliminated. When the balls 8 have left the holes 9, virtually no effort is required to rotate the housing about the pivot pin. The force is transmitted from the toe portion of the boot by the soleholder 7 and the pivot pin 6 to the housing 3 and 4. Until the sole has been released by the safety toe iron, the soleholder 7 follows the pivotal movement performed by the sole in a direction which is opposite the pivotal movement of the housing. The movement of the soleholder is enabled only when a certain force is overcome because the two outer edges of the extension 13 of the soleholder normally bear on the flange 12 of the sheet metal abutment 11. During a pivotal movement of the soleholder, one of the two edges acts on the sheet metal abutment l1 and tends to displace the same away from the pivot pin 6 so that the runup ramps of the abutment run up on the balls 8 and the stress of the helical compression spring 10 is increased.
When the sole is released by the soleholder 7, the springloaded sheet metal abutment will automatically return the soleholder to its normalposition. When the safety toe iron has been opened by hand, the housing 3 and 4 must be swung back until the balls 8 move over the rim of the holes 9, whereafter an exact centering may be automatically obtained.
What is claimed is:
l. A safety toe iron for ski bindings which is laterally pivotally movable in response to an excessive torque comprising a baseplate, a pivot pin secured to and extending vertically from said baseplate, a pivoted member pivotally connected to said pivot pin, said pivoted member comprising a bipartite housing consisting of an upper'portion and a lower portion, a second pivot pin mounted to said bipartite housing, said second pivot pin carrying a pivotable soleholder, ball detent means carried by said bipartite housing lower portion, a flanged abutment means positioned on aid ball detent means, said flanged abutment means comprising a base portion and a flange portion, said base portion defining at least one runup ramp for said ball detent means and being movable in the longitudinal direction of said bipartite housing, said abutment flange portion lying opposite the rear portion of said soleholder in an abutting relation therewith and extending transversely to the longitudinal direction of said bipartite housing, and a spring element placed around said first pivot pin and acting on said base portion of said flanged abutment means'to enable said flanged abutment means to be vertically displaced.
2. A safety toe iron for ski bindings as claimed in claim 1, wherein the surface of the soleholder lying opposite said abutment flange is slightly concave.
3. A safety toe iron for ski bindings as claimed in claim 1, wherein said spring element comprises a helical compression spring.