BACKGROUND ART Roller skates, in particular skates which are referred to as one-track in-line skates, are nowadays utilized not only as equipment for entertainment, which is used only for sport activities, but increasingly also as a means of transport. However, the use of roller skates as a means of transport is often difficult because in many areas, for instance in train stations, supermarkets, etc., the use of roller skates is forbidden. To be able to use this means of transport in spite of this, a skater must carry with him another pair of shoes, for instance to go shopping in a supermarket after he gets there on roller skates. Also a person skating on ice will be facing a similar problem with changing shoes if, for instance, he wants to leave the ice rink during an intermission or wants to walk to a frozen pond to skate there. A hard outer shell of the boots is preferable for use in competitions since it enables a good support for the skater's foot and ankle and it also enables a good transfer of force from the foot to the roller skate. Some skaters who are not as concerned about performance, however, prefer softer and more flexible boots, which are referred to herein as"soft boots".

Snow board riders often loosen at least one of their bindings during the course of a day. This may be necessary, for instance, to get into a ski lift. After that, the binding must be again securely locked. This is very time consuming with known types of binding systems.

A type of in-line skates is commercially available that is integrated with equipment by which the boot can be mounted onto a frame of an in-line skate in a detachable manner. As is usual in the case of in-line skates, the frame has an inverted U-profile and is provided with rollers. Since it must be possible to use the boots also for walking, the boot is designed as a soft boot with a reinforced ankle part. The device for detachable fastening of the boot to the frame comprises four locking mechanisms, each of which comprises a part mounted on the boot (referred to as the"boot part"hereinafter) and a part mounted on the frame (referred to as the"frame part" hereinafter).

The boot part of the first locking mechanism is a hook that is open forward and is inserted into the sole of the front part of the boot. The frame part of the first locking mechanism is an elevation with an opening in the back that receives the hook when the boot is moved forward relative to the frame.

In the rear part of the sole of the boot is inserted a metal bar forming a U-shaped channel that is open downward. This bar extends in the lengthwise direction of the boot from the heel area of the boot to the area under the arch of the foot. The U-shaped channel of the metal bar is designed to be complementary with the shape of a protrusion from the frame. When engaged, the metal bar and the protrusion from the frame prevent the boot from moving from side to side, or in a direction crosswise with the frame. From the front end of this bar a front metal tongue extends forward in such a manner that it can be slid under a pin mounted on the frame by moving the boot forward. The pin is mounted on the upper side of the frame and is oriented to extend across the width of the frame. The front metal tongue and the pin form a fourth locking mechanism (a second and a third locking mechanism are described below) that prevents the boot moving off the frame when the boot is shifted forward to the stop position. The stop position is the position in which at least one of the first and the fourth locking mechanisms prevents the boot from being moved farther to the front relative to the frame.

At the rear end of the frame is located a projecting part provided with a vertical front end face that is approximately 3 mm tall and extends across the width of the frame. When the boot is placed upon the frame for the locking operation, the lower side of the metal bar is first placed on the protrusion from the frame. When the boot is shifted forward until it reaches the stop position, the rear end face of the metal bar is placed just in front of the projecting part's vertical front end face, and the heel of the boot can then be lowered until it is placed on the frame. The vertical front end face of the projecting part and the rear end face of the metal bar form a second locking mechanism that prevents backward movement of the boot.

A rear metal tongue extends from the rear end of the metal bar to the rear and upward at an angle of approximately 45 degrees. At the rear end of the frame is located at the base of the projecting part the lower end of an articulated arm consisting of two segments. The lower end of the first segment rotates about a first axis of rotation at the base of the projecting part that extends across the width of the frame. The second segment is connected to the upper end of the first segment in such a manner that it can rotate about a second axis of rotation that is parallel to the first axis of rotation. The third locking mechanism is provided by engaging one end of the second segment with the free end of the rear metal tongue that extends from the rear of the metal bar and rotating the first segment about the first axis of rotation upward and into a recess in the boot so the second segment can pass through a dead point and snap into an "over-dead-point"position. This third locking mechanism prevents the heel of the boot from being raised off the frame. The second segment is provided with a latch mechanism that automatically engages a hook in the boot recess. This latch mechanism prevents unintentional unlocking of the third locking mechanism.

The above described device for detachable fastening of a boot to the frame of an in-line skate has a number of disadvantages. First, the fastening of these in-line skates is relative compli- cated because the boot must be placed on the frame with the articulated arm moved out of the way so that the boot parts of the first and the fourth locking mechanism are positioned just behind the corresponding frame parts. Second, if the front metal tongue is inadvertently placed

on the metal pin instead of being positioned behind it and pressure is then applied from above, the tongue can become bent making it impossible to fasten the boot to the frame. Third, it is very hard to remove the boot from the frame because, after the articulated arm has been opened, the frame must be held securely while the heel is lifted from the frame and the boot is pushed back with sufficient force to overcome friction between the boot and the frame. Finally, this type of in-line skate is relative complicated due to the many individual parts required and is expensive to manufacture.

Another fastening device is known from WO 94/20176 A1 (see Figures 1 through 11). The front part of the boot is fastened by engaging a projection created on the boot with a corresponding recessed area of the frame. The area of the boot near the heel is fastened by rotating a cam that is supported by the frame and is inserted into a recess in the heel part of the boot. The person fastening the boot to the frame applies force via a lever to rotate the cam that engages a component on the boot, which results in fixing the boot to the frame.

This device also has a number of disadvantages. First, the fastening of these in-line skates is complicated by the fact the cam must be rotated into the proper position to enter the recess in the heel part of the boot. Second, the cam may not be rotated far enough to securely fasten the boot to the frame. Third, even if the cam is initially rotated far enough, it may rotate from vibrations and allow the boot to separate from the frame.

SUMMARY OF INVENTION The object of the present invention is to provide a detachable fastening of boots to a frame of roller skates, ice skates, snowboards, or similar equipment, with an automatically operated locking mechanism that can be easily disengaged and can be manufactured simply and inexpen- sively.

According to one embodiment of the present invention, only two parts forming a first locking mechanism in the front area of the boot need to be engaged with each other by a relative movement of the boot in the lengthwise direction of the frame. Thereafter, an element in the shape of a bar and located in a recess in the heel of the boot can be brought into locking engagement with a locking bar on the frame by simply lowering the heel of the boot. The locking bar according to this invention is pre-loaded into a home position so that the bar-shaped element in the boot presses against and moves the locking bar automatically as the heel is lowered. As the locking bar is moved in this manner it allows the bar-shaped element to pass and to reach its final position. When the bar-shaped element reaches its final position, it releases the locking bar which returns toward the home position under force of the pre-loading. In this state, the locking bar holds the bar-shaped element on the frame and prevents the heel of the boot from being lifted off-the frame. The boot can be released from the frame in a simple manner by operating a releasing device that moves the locking bar into a release position and allows the bar-shaped element to be pulled up by lifting the boot off the frame.

In one embodiment of the invention a groove or similar opening is provided on the frame and receives the bar-shaped element. In its home position, the locking bar reaches into the groove while being fully or partially retracted from it in the release position.

It is advantageous to arrange the groove such that its width is aligned along the length of the frame. This makes it possible to use one of the walls of the groove in cooperation with the bar- shaped element as a second locking mechanism that prevents relative movement between the boot and the frame in a direction in which such movement would unlock the first locking mechanism.

When the first locking mechanism is designed so that, in its locked state (stop position), it provides a stop for a movement backward, it is advantageous to incline the groove so that the distance from its upper end to the first locking mechanism is smaller than the distance from the bottom of the groove to the first locking mechanism. Alternatively, when the first locking mechanism is designed so that, in its locked state (stop position), it provides a stop for a movement forward, it is advantageous to incline the groove so that the distance from its upper end to the first locking mechanism is greater than the distance from the bottom of the groove to the first locking mechanism. With such a design, it is possible to increase the tension in the sole of the boot (to compress the sole in the above mentioned alternative) after the boot part and the frame part of the first locking mechanism have been engaged with each other by merely driving the bar-shaped element to the bottom of the groove. This increases the clamping effect between the boot and the frame and provides a more secure grip that is substantially free of backlash.

The pre-loading of the locking bar in the home position can be realized in a simple manner with a spring.

When the boot parts of the locking mechanisms are arranged in recessed areas of the sole of the boot, these parts will not be in the way when the boot is used for walking and they will be inconspicuous.

Preferably, the recesses in the boot are adapted to snugly fit the corresponding parts of the locking devices on the frame, thereby preventing displacement of the boot in the crosswise direction of the frame.

A particularly simple and effective implementation is achieved when the locking bar is designed in the form of a cam that extends into the groove and pivots about a rotational axis perpendicu- lar to the width of the groove. The upper surface of the cam in the groove has a shape such that, when the cam is in the home position, the bar-shaped element can engage the cam from above and impart a force that causes the cam to rotate. As the cam rotates, it allows the bar- shaped element to move down into the groove past the cam's axis of rotation. When the bar- shaped element reaches the bottom of the groove, it disengages the cam and allows the cam to rotate back toward the home position. The lower surface of the cam in the groove has a shape such that, when the cam is in the home position, the bar-shaped element is held securely in the bottom a the groove.

Further details, characteristics, and advantages of the invention will become clear from the following description of the embodiments of this invention.

BRIEF DESCRIPTION OF DRAWINGS Fig. 1 is an exploded side view of the frame of an in-line skate, a boot which can be attached to it, and an embodiment of a fastening device according to the inven- tion.

Fig. 2 is a top view of the frame shown in Figure 1 showing a locked fastening device as well as the outline of the sole of the boot and the hard shell.

Fig. 3 is a partially broken side view of the in-line skate shown in Figure 1 in which the fastening device is not yet set in the locked position.

Fig. 4 is the same side view as that shown in Figure 3 in which the fastening device is shown in the locked position.

Fig. 5 is a magnified view showing the heel area depicted in Figure 4.

Fig. 6 is a partially broken side view of a snowboard and a frame, a boot and an embo- diment of the fastening device according to the invention which is not yet in the locked position.

Fig. 7 is a top view of the frame shown in Figure 6 showing the fastening device in the locked position as well as the outline of the hard shell.

MODES FOR CARRYING OUT THE INVENTION The following is a description of an example of an application of the mechanism of the invention to in-line skates, wherein references to direction and orientation are based on frame 30, on which boot 10 is to be mounted, being in the horizontal position with rollers 70 placed below it on the floor, which corresponds to normal usage conditions.

Figure 1 shows a side view with a schematic representation of the individual components of an in-line skate comprising boot 10 with a boot upper part, sole 15 and hard shell 11, as well as frame 30 with rollers 70. Hard shell 11 is inserted between the boot upper part and sole 15. The boot parts of the locking mechanisms are formed on or attached to hard shell 11. Respective cooperating parts of the locking mechanisms are provided on the frame. The first locking mechanism is located inthe front area of the skate (the right side of the figure), while the second and third locking mechanism are located in the back of the skate (the left side of the figure).

Figure 2 shows a top view of frame 30 with the locking mechanisms of this invention in the locked position as well as the outline of sole 15 and of hard shell 11.

Hard she) ! 11 can be made from polyurethane (PU), polyamide, or thermoplastic polyolefin (TPO), for example. The lower side of hard shell 11 has a shape complementary to the inside of sole 15 which has a tray-like form. The upper part of hard shell 11 is manufactured to match the bottom of the boot upper part. The boot upper part is made for instance from leather or plastic.

When hard shell 11 and sole 15 are fastened to each other and to the boot upper part, hard shell 11 is positioned in sole 15 as shown in Figures 3 and 4. Hard shell 11 is provided in the heel area and the front area with cutouts 17 and 18, respectively. Downward projecting ribs 19 are integrally formed in the heel area to the right and to the left of cutout 17, as viewed in the skating direction. A bar-shaped element in the form of metal pin 24 is positioned in cutout 17 and integrally formed with the lower ends of ribs 19, for instance, by inserting pin 24 into the mold used to form hard shell 11 before carrying out the molding process. Metal pin 24 is oriented orthogonally to the direction of skating. Plate 21 is screwed onto the lower side of hard shell 11 with screw 23 so that cutout 18 is largely covered and only a narrow gap 20 is left free at its rear end. The bottom side of hard shell 11 is beveled in the middle, as seen in cross- direction, to the rear end of cutout 18 in the upward direction so that a slot is formed between shell 11 and the upper edge of plate 21. Slanted surface 22, created by beveling, is indicated by a dot-dash line in Figure 2. The dashed line in Figure 2 represents cutout 18.

As was already mentioned, the purpose of detachable fastening of the boots to the frames is to make it possible to use the boots for walking. That is why shell 11, which is referred to here as a hard shell, must be manufactured in such a manner that, on the one hand, it displays the sturdiness that is required to anchor the boot parts of the locking mechanisms but, on the other hand, enables the boots to be flexible enough for walking. Different profiles, thicknesses and/or material characteristics along the length of hard shell 11 can be used to achieve the degree of strength and flexibility that is required. For example, ribs 19 contribute in the heel region to a firm mounting support for pin 24. As is explained below, because hard shell 11 is braced when boot 10 is locked onto the frame 30, it is possible to achieve a firm fastening of the boot to the frame in spite of the flexibility of hard shell 11.

Sole 15, which is located under hard shell 11, can be made of rubber or technical rubber (TR), for example. While sole 15 is shown in the depicted embodiment as having one part, it can alternatively comprise two parts, namely a rear or heel part and a front part. Rectangular cutouts 14 and 16 are provided in heel 13 and in footpad area 12 of sole 15, respectively. These cutouts 14 and 16 penetrate completely the heel 13 and the footpad area 12. As viewed from above, cutout 14 and cutout 17 have the same profile but cutout 16 is larger than cutout 18 in both the lengthwise and in the crosswise directions. Both pin 24 and plate 21 are accessible from below through cutouts 14 and 16, respectively, but they do not project below the bottom of sole 15. This makes it possible to walk in the boots without any hindrance due to pin 24 or plate 21.

Frame 30 essentially has the form of a rail with an inverted U-profile. Hook 40, which projects forward and upward, is screwed to frame 30 on the front end at the upper side of the frame.

Hook 40 and plate 21 together form the first locking mechanism.

Part 44 is also screwed to frame 30 and, together with pin 24 in the boot, forms the second locking mechanism that prevents boot 10 and frame 30 from moving relative to each other so as to release the first locking mechanism. Part 44 and pin 24 also form the third locking mechanism that fixes boot 10 onto frame 30 in the vertical direction. In this embodiment, part 44 is a block that, when viewed along the length of the frame, has a U-shaped profile open in the upward direction. Legs 43 on either side of the U-shaped profile are parallel with one another along the length of the frame. Locking bar 46, shown in the figure as a cam, pivots between legs 43 around horizontal rotational axis 49 which is perpendicular to the lengthwise direction of the frame. Groove 45 is provided in front of cam 46 in each leg 43 for insertion of pin 24. One part of spiral spring 61 is mounted on rotational axis 49 on each side of cam 46 between cam 46 and the respective one of legs 43. The spring biases cam 46 into a home or first position in which cam 46 reaches into groove 45. In other words, in its home position, cam 46 reaches into the space between both legs 43 that is defined by the projection of groove 45 in one leg onto that in the other leg. In this embodiment, the two grooves in legs 43 and the corresponding space between the legs are collectively referred to as"groove 45". In this case the groove "walls"are formed by the edges in legs 43 defining the grooves. In an alternative embodiment, part 44 can be formed from a block with a groove extending through it crosswise and having a cutout for the cam in one of the groove walls. Based on the principle of the present invention, however, no particular shape of the groove is essential. Mounted behind cam 46, releasing mechanism 60 enables manual unlocking of cam 46. A detailed description of cam 46 and releasing mechanism 60 is provided below.

The profile views shown in Figures 3 and 4 provide a more detailed representation of the locking mechanisms in the areas encircled by a dot-dash line. Both sole 15 and the rear part of leg 43 are shown cut away in these figures and in Figure 5 for illustrative clarity.

As one can see from Figure 3, boot 10 is fastened to frame 30 by placing the tip of the boot on frame 30 with plate 21 in front of hook 40 and then pulling boot 10 back relative to frame 30 in the direction of arrow A. This brings plate 21 into the horizontal stop position and provides vertical positive locking with hook 40 on the frame. Incidentally, slanted surface 22 mentioned above is provided to facilitate engaging hook 40 with plate 21. Heel 13 is then lowered, which moves pin 24 in the direction of arrow B and inserts it into groove 45 so that it comes to rest on the bottom of the groove. During its way from the upper end of groove 45 to the bottom of the groove, pin 24 rotates cam 46 from its home position to a release or second position. In its release position cam 46 is at least partially retracted from groove 45 enough to allow pin 24 to pass cam 46 and reach the bottom of the groove. After that, cam 45 rotates back toward its home position under the biasing force applied by spring 61, thus blocking movement of pin 24 out of groove 45.

This locking mechanism will now be further explained with reference to Figure 3 and the enlarged illustration shown in Figure 5. Cam 46 is supported by rotational axis 49 so that it can be rotated. The rotational axis runs behind groove 45 in the crosswise direction of the frame. As shown in the Figure 3, cam 46 is in the home position. When pin 24 is moved downward in the

direction of arrow B, it engages the lower part of surface 47 of cam 46, which has a concave shape. The force exerted on curved surface 47 of cam 46 by the downward movement of pin 24 causes cam 46 to rotate in the clockwise direction until pin 24 has passed the farthest protruding lower part of curved surface 47. The concave curve must be large enough to allow this passing movement. After that, cam 46 will rotate in the counter-clockwise direction under force applied by spiral spring 61 towards the home position. In a preferred embodiment of the invention, the cam will not completely return to its home position due to lower surface 50 of cam 46 abutting pin 24. As pin 24 moves further down to the bottom of the groove, cam 46 can rotate closer to its home position. Even when pin 24 is at the bottom of the groove and cannot move further down, however, cam 46 does not fully return to its home position but is in an intermediate third or locking position instead. Figures 4 and 5 show the locking position while Figure 3 shows the home position of cam 46. Lower surface 50 of cam 46 is pressed against pin 24 under the force of spiral spring 61. This lower surface 50 of bottom side 48 of the cam is designed so that, for at least the lower part of this surface, the radial distance from the surface to rotational axis 49 of cam 46 decreases from the bottom to the top or, as shown in the figure, decreases in the counter-clockwise direction. This shape provides a locking mechanism that securely holds pin 24 on the bottom of groove 45 substantially without backlash. As pin 24 is pulled upward during skating, for example, friction between pin 24 and surface 50 causes a turning moment to be exerted on cam 46 in the counter-clockwise direction. Any movement of cam 46 in the counter-clockwise direction would, due to the shape of surface 50, increase the pressure that clamps pin 24 between cam 46 and the bottom and the front edge or wall 42 of the groove. As a result, the front wall 42 of groove 45 and the cam 46 cooperate to lock the pin 24 in the vertical direction, thereby providing the function of the third locking mechanism described above for the prior art and, at the same time, lock the pin 24 in the horizontal direction, thereby providing the function of the second locking mechanism described above for the prior art. This makes it possible for cam 46 to provide a safe and essentially backlash-free grip of pin 24, as shown in Figure 4 as well as in the enlarged representation shown in Figure 5.

It is preferable that the shape of cam 46 is designed in such a manner that the cam assumes the intermediate locking position explained above. An essentially backlash-free grip of pin 24 can also be achieved, however, when the cam's locking position is substantially identical with its home position rather than being an intermediate position. In this latter case a more precise and, thus, more expensive manufacturing is required.

It is to be noted that, in the embodiment described above, the respective portion of both legs 43 located on the rear side of groove 45 is only used as a support for cam 46 and, beyond that, does not contribute to the third locking mechanism or to the second locking mechanism. In other words, only the front wall 42, not the rear wall of the groove is used for the locking mecha- nisms. On the other hand, in an embodiment where plate 21 on the boot is open in the forward direction and the hook 40 is open backward on the frame, the respective portion of both legs 43 located on the front side of groove 45 can be omitted. In this case, only the rear wall, not the front wall of the groove is used for the locking mechanisms.

Furthermore, relative to the position illustrated in the figures, part 44 couid be turned 180 degrees about a vertical axis without affecting the functioning of the second and the third locking mechanisms. In such an alternative, with the structure of the first locking mechanism as shown in the figures and described above, the respective portion of both legs 43 located on the rear side of groove 45 is no longer required as a support for cam 46 and can be omitted.

Cam 46 can be rotated from the locking position to the release position by operating a releasing mechanism. In the example shown in the figures, the releasing mechanism comprises loop 60, which can be made of a textile or a plastic material, for example. Loop 60 is attached with one or more screws 23 to the rear side of cam 46 in such a way that cam 46 can be rotated into the release position by pulling on loop 60. In an alternative embodiment, instead of the loop, it is possible to use a lever or a strap that is connected to cam 46. The force applied by spring 61 to cam 46 should be adjusted so that, on one hand, cam 46 is reliably brought into the locking position after pin 24 is seated in groove 45 (or the home position when the boot is detached) and yet, on the other hand, only a reasonable amount of force is required to overcome spring 61 when the cam 46 is being driven to the release position to release pin 24.

In the embodiment illustrated in Figures 3 and 5, groove 45 is slanted so that its upper end is closer to hook 40 than is the bottom of the groove. This inclination is generally preferred because, during the lowering of heel 13, pin 24 moves along an arc rather than a straight vertical line. If groove 45 is inclined more than what is required to account for this non-liner motion, an additional advantage is that hard shell 11 and, with it, sole 15 of boot 10 are slightly stretched between pin 24 at the front wall 42 of groove 45 and plate 21 at hook 40. If hard shell 11 and sole 15 are convex to facilitate a"rolling away"movement of the boot that makes walking more comfortable, such stretching is more easily possible. Moreover, such an inclination of groove 45 has the advantage that as the heel of boot 10 is moved downward, the tip of boot 10 and plate 21 are pulled backward and brought to the stop position on hook 40 if this has not occurred already. Preferably, the upper end of front wall 42 of groove 45 is rounded as shown in all the figures.

In an embodiment where plate 21 on the boot is open in the forward direction and the hook 40 is open backward on the frame, the open end of groove 45 should be inclined away from hook 40 to achieve a similar bracing effect by clamping.

An additional clamping effect as well as an assist for centering the front part of the boot in the crosswise direction can be achieved by forming both cutout 18 and hook 40 to be somewhat narrower in the front than is illustrated in Figure 2. This makes it possible to insert the front, narrower part of hook 40 easily from the back into the opening of cutout 18 and to achieve automatic centering as thé-look is moved forward and both of its side edges come into contact with the lateral inner surfaces of cutout 18. The centering and additional clamping in the heel area can be achieved in a similar manner, for instance, by shaping part 44 to have a width that increases from the top to the bottom and by dimensioning cutout 14 and/or cutout 17 in such a way that their left and right side walls come into contact with the corresponding outer sides of part 44 when pin 24 gets into its locked position.

When loop 60 is long enough so that cam 46 can be easily unlocked, it could touch the last roller or become entangled in objects during roller skating. Such an entanglement could cause cam 46 to rotate and release pin 24. This danger can be eliminated by providing the upper side of loop 60 with a Velcro strip that can be pressed onto a counterpart strip on the back of the boot. This feature is not shown in the figures.

Alternative embodiments may use a wide variety of structures to implement the first, second and third locking mechanisms. For example, the groove 45 is not required to implement the second and third locking mechanisms but is useful to explain the concept of this invention. In one alternative embodiment, the legs 43 can be replace by a single structure that provides a suitable support for locking bar 46 and prevents bar-shaped element 24 from allowing hook 40 to move away from the stop position while engaging plate 21.

Although the description above relates to fastening boot 10 to frame 30 placed in a fixed position on the floor, it goes without saying that boot 10 can be held in a fixed position and frame 30 moved. Furthermore, the frame need not be placed on a floor.

Figures 6 and 7 explain an application of the invention to snowboard 90. Figure 6 shows a partially broken side view similar to Figure 3 and Figure 7 depicts a top view similar to Figure 2.

The mechanism for fastening the boot to the frame of the snowboard is designed in the same or substantially the same way as that of the in-line skates and has the same characteristics. Also the functions of the mechanism and the procedure used to lock and unlock the mechanism are similar. Because of the similarity, another complete explanation is not required. The following paragraphs discuss some differences between the two embodiments.

Instead of frame 30 of the in-line skates, the snowboard is provided with board-shaped frame 80, which is a binding board similar to that used with many types of snowboards. The frame parts of the rear locking mechanism and the front locking mechanism are attached to frame 80 with screws 85. Although frame 80 is depicted in Figure 7 as a hexagonal plate, it can have a different form. Rotatable disk 82 is fastened with screw 84 to frame 80 between the rear locking mechanism and the front locking mechanism. Although the disk shown in Figure 7 is depicted as a round disk, it does not need to have this form. This disk 82 is provided with two pairs of oblong holes 86 penetrating disk 82. Each pair of oblong holes is collinear and posi- tioned diametrically opposite the other pair with respect to screw 84. A screw 83 through each oblong hole 86 can fasten disk 82 and frame 80 connected thereto to snowboard 90. In addition, frame 80 is provided with four through holes 88, each of which has the form of an annular sector. On the one hand, through holes 88 are designed and arranged to enable rotation of disk 82 with respect to frame 80 around the axis of screw 84 in spite of the screws 83 through oblong holes 86. On the other hand, through holes 88 also enable a linear shifting of disk 82 and frame 80 relative to the snowboard along the lengthwise direction of oblong holes 86. This enables the device according to this invention to be fastened to a snowboard and to be oriented optimally.

The application of this invention is not limited to in-line skates and snowboards, but can be applied to other equipment such as roller skates with two pairs of rollers (arranged in two pairs), ice skates and short skiing equipment such as, for instance, the so called Bigfoot where, because of the short length of the ski, the safety aspect of automatic release from the binding is not important. A device according to this invention could also be provided with the parts forming the third locking mechanism turned by an angle of 90 degrees about a vertical axis compared to the embodiment described above. Locking bar 46 would then be mounted on a side of groove 45 as seen in the direction of skating (rather than behind or in front), and preferably located on the side opposite of the other boot to prevent respective locking bars and/or respective releasing mechanisms from touching one another during skating.

Locking bar 46 can be also designed as a locking pin instead of having an eccentric shape, which is slidably supported so that it can be moved into and out of groove 45. Removal from groove 45 could then be performed for instance through a corresponding beveiing of the end which is protruding into the groove. When the path of the locking bar is inclined so that the locking bar will slide on its own as a result of force of gravity into groove 45, a biasing spring can be avoided. The principe of biasing into the home position by force of gravity is also applicable to cam 46 by suitably designing the shape and the mass distribution of the cam.

However, a spiral spring or a suitable alternative spring configuration is advantageous since it operates independently of the given posture of frame 30. Pin 24 need not be made of metal but can, for example, be manufactured from plastic that is capable of withstanding the load applied to it during use. Furthermore, pin 24 can be attached to hard shell 11 or to heel 13 in essentially any manner that provides sufficient strength to serve the purpose of this invention.

In an alternative embodiment, a groove in frame 30 and a cooperating pin in boot 110 is used instead of hook 40 and plate 21. In this embodiment, the groove in frame 30 is approximately vertical and extends in the crosswise direction. The groove can be inclined forward or backward, respectively, to achieve a clamping effect as described above.

The invention does not require that parts of the locking mechanisms be provided in the footpad area 12 or in heel 13 of sole 15. Instead, they can be mounted on the lateral sides of the boot, which does not affect function but, of course, the part of the locking mechanisms on the frame has to be adjusted to accommodate differences in position.

The attachment of different parts with screws 23 should be regarded solely as an example.

Fastening with rivets or glue, for example, can be also used.