A swimming flipper and a shoe therefor

The present invention refers to a swimming flipper, particularly a swimming flipper for divers, and a shoe therefor.

A swimming flipper known from EP 0 572 853 Bl comprises a blade of flexible but relatively rigid material and a shoe associated to an end of the blade, wherein the blade and the shoe consist of two distinct elements which can be separated from one another and are provided with mutually releasable coupling means, which include: rear locking means which perform a quick automatic snap-fit engagement following approach of the shoe and blade relative to each other in a direction substantially perpendicular to the plane of the blade, front locking means, cooperating with the rear locking means, for locking the shoe so as to perform full automatic and rigid snap-lock of the shoe on the blade, without any need for manual intervention.

The coupling means disclosed in the aforementioned European patent certainly represent a progress with respect to conventional flippers equipped with a fastening strap in the heel zone. With those conventional flippers, the diver must use his hands to fasten the straps, which is a difficult operation requiring effort, if one considers that the equipment mounted on the diver's back may weigh over 20 kg, and thus it is easy to lose balance and fall. Moreover, conventional straps tend to wear with time and therefore have a limited lifetime; the straps are fastened by side buckles which are also subjected to crashes, for example against rocks. This may cause loss of the flipper, which is particularly dangerous, especially if it happens underwater.

A main object of the present invention is to provide a flipper capable of being bound to the shoe in a particularly steady, safe and quick way, without running the risk of the flipper coming off while swimming.

A particular object of the invention is to provide a particularly reliable coupling between the shoe and the flipper, reducing to a minimum the deformation of the flipper with respect to the shoe, and the relative transversal and rotational movements, in order to gain maximum efficiency of the swimming movement.

Another object of the invention is to provide a swimming flipper at a low manufacturing cost, preferably by moulding a single plastics material in a single step.

These and other objects and advantages, that will become apparent in the following, are attained in accordance with the invention by a swimming flipper having the features defined in the accompanying claims.

A few preferred but not limiting embodiments of the invention will now be described, reference being made to the attached drawings, in which: - FIG. 1 is a vertical longitudinal cross sectional view of part of a swimming flipper according to the invention;

FIG. 2 is view similar to that of FIG. 1 , with a shoe associated with the flipper blade; FIG. 3 is a top view of the blade of FIG. 1;

FIG. 4 is a rear view of a shoe for a flipper according to the invention; - FIG. 5 is a partially sectioned side view of the shoe of FIG. 4;

FIGs. 6, 7 and 8 show a variant embodiment of the invention; FIG. 9 shows a further variant of the invention;

FIG.10 is a cross sectional view of the quick locking device of the invention; and FIGs. 11 and 12 are views, similar to that of FIG. 2, of two further variants of the invention.

Referring initially to FIGs. 1 to 5, a blade 10 for a swimming flipper is made by a single moulding step of a flexible but relatively rigid plastics material. A shoe indicated as a whole at 20 is releasably coupled to the rear part of the blade.

For fitting in and locking the front part of the shoe 20, the blade forms an arched seat 11 delimited from above by an arched projection 12 and underneath by the upper resting plane 13 of the blade. As an alternative to the embodiment shown in full line in FIG. 2, the front seat for the shoe may be made by extending the arched projection 12 upwards, as shown in phantom at 12a in FIG. 2, so as to lock from above and sideways also a considerable part of the vamp of the shoe.

As shown in FIGs. 4 and 5, formed in the heel of the shoe is a downwardly open channel 15 extending longitudinally towards the rear end of the heel. Preferably, channel 15 has a transversal cross section of polygonal shape, in this example of rectangular shape. The channel 15 is crossed transversally by a pin or bar 16 located at a certain distance from the bottom of the shoe.

In the embodiments illustrated herein, a quick locking device 30, visible in FIGs. 1, 2 and 10, is integrated in the blade 10. The quick locking device 30 comprises an elongate, rectilinear guiding casing 31 in which a slider or latch 32 is accommodated and longitudinally guided.

The latch 32 has a front tapered end with an upper surface 33 inclined forwards and downwards. In the condition shown in FIGs. 1 and 2, the inclined surface 33 is aligned with an opening 36 formed in the upper front portion of the casing 31. Fitted within casing 31 is a return spring 34 that tends to urge the slider 32 forwards, whereas indicated 35 is a stem provided with a gripping means 37 the projects from the rear of the flipper and serves to allow the shoe to be manually released from the blade.

In order to put the flipper on, the user wearing the shoe must introduce the tip of it into the front seat 11. After that, the user presses the heel down: the transversal bar 16, located at the opening 36, acts on the inclined surface 33 of the slider 32, urging the latter rearwards against the elastic thrust offered by the spring 34. Once the bar 16 has passed over the front end of the slider, this snaps forward (FIG. 2). In this locked condition, upon lifting the shoe also the blade will be lifted with it, owing to the bar 16 engaging the lower surface of slider 32.

Preferably, the channel 15 formed in the heel has a cross section of a shape congruent with that of the casing 31 and/or a part of the rubber or plastic coating that covers the casing 31. The congruent shapes of the channel formed in the heel and the casing of the quick coupling device allows to take up the play, particularly transversal, rotational and torsional movements between the blade and the shoe.

In the variant shown in FIGs. 6 to 8, the front means for locking the foot consist of a ring 22 formed integral with and protruding from the front portion of the shoe, and a corresponding downwardly extending hook formation 23 secured to the blade 10. The front ring 22 is hooked from underneath by hook 23 and held down by the latter, thereby ensuring that the tip of the shoe is retained against the blade.

In FIG. 9 an alternative example is shown where the rear end of the stem, projecting from the flipper, is ring-shaped. The rear gripping ring 37 may be connected through a cord 38 to a gripping tab 39 that serves to release the locking device more easily. The tab 39 may be associated with a hook and loop or Velcro® attachment 40 to hold the tab neatly adherent to the heel of the shoe while using the flipper.

In the locking device 30, the stem 35 and/or the slider 32 may be associated to anti-rotation means with the casing 31, in case the slider 32 and the casing 31 have a circular cross sectional shape. In order to prevent relative rotation between these two members, so as to ensure that the inclined face 33 is always facing the opening 36, i.e. upwards, guides and/or slots may be provided at the interface between the casing 31 and the slider 32. As an alternative, the rear wall of the casing from which the stem 35 comes out may be shaped correspondingly to this, for example with a square cross section.

Shown in FIGs. 11 and 12 are other two possible variants of the invention, according to which the arched projection 12a of FIG. 2 extends upwards and laterally so as to form essentially a vamp portion 12b which covers from the outside the vamp of the shoe and encompasses and holds the front of the foot. The so extended seat 12b also offers the possibility of simplifying

the shape of the front means for locking the shoe and the shoe itself, as shown in the variant of FIG. 12. The seat 12b will preferably be made of a rubber-like material relatively more flexible and softer than that which the blade 10 is made of.

As will be appreciated, the elastic member to which the quick locking action of the heel is referred consists of an element which is distinct from the flipper bade and the shoe. As in the preferred embodiment shown in the drawings, the elastic element advantageously is a steel spring 34. The blade of the flipper may be made of a more rigid plastic material, since it should not have to provide also an elastic element for releasably retaining the shoe, as in the case of EP 0 572 853 Bl . The elastic action offered by the spring 34, and the rigidity of the slider 32, as well as the shape and mutual arrangement of the various parts constituting the locking device 30, ensure that the shoe is steadily fixed on the flipper blade.

As compared to conventional swimming flippers, that usually consist of more rubber and plastic parts overmoulded one onto the other, the present invention advantageously allows to manufacture the flippers at low cost, by moulding the blade in one material through a single moulding step.

The improved locking of the blade to the heel of the shoe allows all the strength of the movement imparted to the flipper to be transferred to the blade, preventing the heel from oscillating relative to the blade, and thus attaining maximum efficiency. Moreover, projecting parts that could reduce hydrodynamic efficiency are eliminated. It will be appreciated that in the present invention wearable and breakable elements are absent, such as conventional straps and other laterally protruding parts for fastening the strap to the blade.

The flipper can be put on easily and quickly, and this may be done from a standing position, without the risk of losing one's balance and falling. The user does not need to use his hands to put the flipper on. Also the removal of the flipper is facilitated, since it is done using only one hand with a simple pulling movement. Thus, all drawbacks of a difficult removal with currents or high waves are eliminated.

Another advantage attainable by the invention is that the number of sizes of the blade can be reduced, for example making only three sizes (small, medium, large), where each of these sizes is adapt to fit several sizes of the shoe, all of which will have the same distance between the tip and the rear flipper retaining bar or pin.

The invention is not intended to be limited to the embodiments described and illustrated herein, which should be considered as implementing examples of the flipper; rather, the invention may be modified with regard to the shape and arrangement of parts and to constructional and functional details. For example, as an alternative to what is shown in the drawings, the quick coupling device 30 may be made in the body of the heel of the shoe, whereas the retainer bar 16 will be fixed to the flipper blade.