Sports shoe fitted with' an adjustable air cushion
The invention relates to a sports shoe, provided with a heel part, in which an air cushion is accomodated.
Sports shoes of this type are well-known. The advantage of the air cushion is the absorption of the shock which occurs when a user puts down his heel, through which the risk of injuries to for example the Achilles tendon is considerably lower. Beside this the air cushion works like a spring; part of the energy absorbed on placing the heel down benefits the user when starting the next step. Without doubt the latter point is an advantage, but it is not experienced as such by all users. The invention at issue meets this drawback to a high extent, and is characterised in that the sports shoe is further provided with at least one duct, a first end of which is connected to the air cushion, and a second end of which is connected to the surrounding atmosphere. Because of this leak the springy effect will decrease, whereas the shock absorbing effect will be retained.
A favourable embodiment of the inventive sports shoe is characterised in that the duct is provided with a restriction near the second end, which makes it possible to adjust the leak size and thus the remaining springiness individually. Another favourable design is characterised in that the second end is provided with a small spout, on which an accessory can be placed, provided with the constriction.
A favourable embodiment according to a further aspect of the invention is characterised in that the sports shoe is provided with adjusting means for adjusting a diameter of the constriction. One can regulate the extent of
springiness during running, depending on for example ground conditions. For instance, the user can attach the second end to an opening in a first plate, fastened to one of the sides of the sports shoe. In a favourable embodiment a second disc-shaped plate is rotatably mounted to the first plate, which second disc-shaped plate is provided with a number of different constrictions. So a different constriction can be selected in a simple and reproducible way.
Another favourable embodiment is characterised in that the second disc-shaped plate is larger than the first plate and is provided with notches and/or indica on its circumference. In this case the notches make sure that selecting a constriction can be carried out simply, also with sweaty hands for example, whereas the indications make sure that a previously selected constriction can be chosen without problems .
A favourable embodiment according to a further aspect of the invention is characterised in that a third plate is provided, attached to the first plate and provided with an opening which at least substantially corresponds with an opening in the first plate, and that the third plate is provided with a small spout, mounted near the opening in the third plate. The spout can for instance be fitted with an object that produces a sound when air is ducted through it, which results in the production of a sound every moment one of the feet touches the ground. Apart from a joyous and playful aspect, this feature may also have an educational effect, for instance when runners should retain the same pace during a training.
A favourable aspect according to another aspect of the invention is characterised in that the sports shoe is provided with additional aerating means for the air
cushion, so that one can be sure that the air cushion is filled with air at the moment the heel hits the ground, independent of the air resistance of the restriction chosen. The additional aerating means may for examole be realised as an additional duct, in which a valve is placed, in such a manner that air can flow into the air cushion but cannot escape.
A further favourable embodiment is characterised in that the additional aerating means comprise a valve, mounted in the spout. A valve of that kind can be placed in a simple manner and it will not easily get dirty.
The invention also relates to a small whistle or pipe fitted with a reed or other object that is fitted to produce a sound, suitable for being fastened on a sports shoe as described above.
The invention will be explained in more details now, with a reference to the following figures, in which:
Fig. 1A shows in perspective a possible design of a sports shoe, fitted with an air cushion, a duct, and a small spout; Fig. IB shows in detail a possible design of a spout in a folded position; Fig. 1C shows in detail a possible design of a spout in unfolded position; Fig. 2 shows in perspective a possible design of a sports shoe, fitted with an air cushion, a duct, and a disc fitted with constrictions; Fig. 3A shows the disc fitted with constrictions from above; Fig. 3B shows this disc in side view;
Fig. 4A shows the disc fitted with constrictions and a spout from above; Fig. 4B shows this disc in side view;
Fig. 5A shows a small whistle that can be placed on the spout;
Fig. 5B shows a small pipe fitted with a reed that can be placed on the spout; Fig. 6A shows in cross section an alternative embodiment of a spout 7; Fig. 6B shows in cross section an alternative embodiment of a shoe.
Fig. 1A shows in perspective a possible design of a sports shoe 1, fitted with an air cushion 2 in the heel part, which air cushion 2 is connected to the open air by means of duct 3, a synthetic hose or pipe. In this design duct 3 is finished off on a synthetic plate 4 which is attached to the outside of shoe 1, for example glued. Inside shoe 1 duct 3 is concealed in a padding between the outside cover of shoe 1 and a lining, in such a way that on putting on or taking off shoe 1 virtually no force has effect on duct 3. A synthetic plate 5 has been screwed on plate 4 with screw 6, and spout 7 is fixed countersunk in plate 5, connected to duct 3 by means of an opening in plate 4, closing off duct 3 in this countersunk position. When spout 7 is unfolded, duct 3 is opened, and the springy effect of air cushion 2 decreases. The heel part of shoe 1 may be fitted with for instance studs or springs or any other pushing system which makes sure that air cushion 2 will be quickly filled again with air when the user lifts the heel of shoe 1.
Fig. IB shows in detail a possible design of spout 7 in folded position, at which spout 7 is almost completely
countersunk in plate 5,' and at which the interior duct of spout 7 is disconnected from duct 3, closing it off.
Fig. 1C shows in detail a possible design of spout 7 in unfolded position, at which the interior duct of spout 7 is a continuation of duct 3, giving only a limited air resistance .
Fig. 2 shows in perspective a possible design of sports shoe 1, fitted with an air cushion 2 in the heel part, which - air cushion 2 - is connected to the open air by means of duct 3, a synthetic hose or pipe. In this design duct 3 is finished off on a synthetic plate 4 , attached to the outside of shoe 1, for example glued. Inside shoe 1 duct 3 is concealed in a padding between the outside cover of shoe 1 and a lining, in such a way that on putting on or taking off shoe 1 virtually no force has effect on duct 3. A pivotable synthetic disc 8 has been tightened on plate 4 with screw 6. Disc 8 has been fitted with a number of constrictions, one of which can be selected and turned before the exit of duct 3. This way the absorption of air cushion 2 can be simply regulated.
Fig. 3A shows a piece of regulating equipment as disc 8, fitted with constrictions 9a,..., 9f, one of which can be placed before the exit of duct 3 by rotating disc 8 for realization of the absorption desired. Disc 8 is fitted with a notched edge on its circumference to make rotating easier, and has been screwed in plate 4 with screw 6 and fastened for example with a bit of glue.
Fig. 3B shows this disc 8 in side view, fastened on plate 4 with a screw 6, attached to shoe 1 that is not shown here. Further duct 3 is visible, the end of which is attached, for example glued, on plate 4.
Fig. 4A shows plate 5 from above, in which spout 7 can be found partly countersunk. Plate 5 is attached to disc 8 which is fitted with the constrictions 9a,..., 9f. Plate 5 and disc 8 are fastened on plate 4 with screw 6, not visible in this figure, at which screw 6 is fastened in plate 4 for example with some glue, and at which plate 5 is also fastened on screw 6 for example with some glue, all things in such a way that disc 8 can rotate freely and that spout 7 is positioned exactly above duct 3. Disc 8 has indications near its edge, here the letters A,.., F, one of which can be rotated before an indication, for instance an arrow 10 on shoe 1, to select one of the constrictions 9a, .. , 9f .
Fig. 4B shows plate 5 in side view, fixed on disc 8 and plate 4, at which plate 5 is fastened in plate 4 with screw 6 through disc 8. Spout 7 is visible as well, here in unfolded position, whereby air can escape from air cushion 2 when the user of shoe 1 places the heel on the ground, and in which air can be absorbed when the heel is lifted again.
Fig. 5A shows a whistle 11 that can be placed on spout 7. This has its result that every time the heel of shoe 1 is put on the ground, part of the escaping air escapes through opening 12, at which a brief whistling signal is made. Depending on details of the construction of whistle 11 this can also be the case when the heel of shoe 1 is lifted up.
Fig. 5B shows a pipe 13 that can be placed on spout 7, fitted with an opening 14 in which reed 15 is placed, similar to the source of sound of a harmonica. The result is that every time the heel of shoe 1 is placed on the ground, part of the escaping air escapes through opening 14 around reed 15, at which a brief harmonica-like signal will
be made, the pitch of which is determined by the properties of reed 15. Depending on details of the construction of pipe 13 and reed 15 this can also be the case when the heel of shoe 1 is lifted again. It will be clear that other objects as well may be placed on spout 7, producing sound on passing air.
Fig. 6A shows in cross section an alternative embodiment of a spout 7. Onto spout 7 a pipe 13 is placed that may produce a sound but which also may have a significant air resistance. In order to simplify the filling of air cushion 2 when shoe 1 is lifted, a valve 16 is placed in spout 7, in such a manner that no air can escape via this valve but that air can be sucked in. In the embodiment shown here, valve 16 consists of a small sphere 17, made of a light material like plastic, that in case of an overpressure is pushed into an edge 18 and thus provides a seal, while in case of an underpressure the air may flow in freely. Sphere 17 is kept in place with the aid of a steel pin 19, fixed into spout 7.
Fig. 6B shows in cross section an alternative embodiment of a shoe 1. In order to simplify the filling of air cushion 2 when shoe 1 is lifted, a valve 16 is placed in the heel, in such a manner that no air can escape via this valve but that air can be sucked in. In the embodiment shown here, valve 16 consists of a tube 20, in which an opening 21 made of an elastic rubber is placed which closes in case of an overpressure in air cushion 2. Tube 20 can be removed easily if desired, so that valve 16 and air cushion 2 can be cleaned, for example when the shoe has been used in a very muddy environment.