Braking device particularly for skates with aligned wheels
BACKGROUND OF THE INVENTION 
     1. Field of the invention 
     The present invention relates to a braking device particularly for skates with aligned wheels. 
     2. Description of the Prior Art 
     Bringing the skate to a full stop during sports practice is currently a problem for the skater; in conventional skates, a brake constituted by a block of plastic material is in fact associated to the rear of the wheel supporting frame, and said block is made to interact with the ground by rotating the skate backward. 
     However, this operation is hazardous, since it can cause the skater to lose his balance, with dangerous consequences. Furthermore, the block wears considerably and must be replaced very frequently. 
     Solutions are also known which provide form the interaction of a brake directly on the rolling surface of the wheel: the consequent drawback is of course the need replace the wheel frequently. 
     SUMMARY OF THE INVENTION 
     The aim of the present invention is to solve the described drawbacks by providing a skate which allows the skater to stop it or reduce its speed while preserving the wheel from wear and allowing the skater to perform the maneuver in safety. 
     A further object is to provide a skate with aligned wheels which allows the skater to achieve better braking control. 
     Another important object is to provide a skate which has a simple structure and is easy to industrialize. 
     Another object is to provide a braking device which is reliable, safe in use and has very low manufacturing costs which allow its widespread diffusion and application even to conventional skates. 
     This aim, these objects and others which will become apparent from the following description are achieved by a braking device as claimed in the appended claims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Other objects will become apparent during the following description, which must be considered together with the accompanying drawings, which illustrate, by way of non-limitative example, a particular embodiment, in which: 
     FIG. 1 is a partially sectional side view of a portion of a skate wherein the device is shown in the inactive condition; 
     FIG. 2 is an exploded partial view of some of the components of the device; 
     FIG. 3 is a cross section view of the device, taken at the element associated with the frame, in the braking conditions. 
    
    
     DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION 
     With reference to the above figures, and considering that they exemplify a particular embodiment and are in variable scale and that identical or equivalent parts correspond to individual reference numerals in said figures, the numeral 1 designates the braking device, particularly for skates comprising a U-shaped frame 2 with first wings 3 and 4 directed toward the ground 5; a plurality of mutually aligned wheels 6 is pivoted to the wings. 
     The braking device is constituted by an element 7 which is composed of a central body 8 which is associated between the first wings 3 and 4 of the frame 2 so that it can swing about a first pivot 9. 
     The central body 8 is partially accommodated within the frame 2 and can swing in contrast with an elastically deformable element, such as a spring 10. 
     The central body 8 has a first end 11, arranged outside the frame 2, which is formed by a shell 12 having the second wings 13a and 13b. A roller 15 is freely pivoted, by means of a second pivot 14, below the second wings 13a and 13b and interacts with the ground 5 upon a backward rotation imparted to the skate. 
     The spring 10 can be interposed, in a pre-compressed condition, between the central body 8 and the frame 2 so that the second wings 13a and 13b of the shell 12 remain in abutment against the first wings 3 and 4 of the frame 2: this allows to keeps the roller 15 raised from the ground during normal sports practice. 
     The central body 8 has a second end 16 which arranged inside the frame 2 and surmounts one of the wheels 6 in the condition for normal sports practice. The second end 16 also has a surface 17 which faces the wheel 6 and has a concave shape so as to form two inclined planes 18 and 19 which interact with the lateral surfaces, or with the surfaces adjacent to the rolling surface, of the underlying wheel 6 during braking. 
     Braking occurs upon a backward rotation of the skate, determined by the skater, which makes the roller 15 touch the ground 5. 
     This leads to the rotation, about the first pivot 9, of the element 7, which further compresses the spring 10 and makes the inclined planes 18 and 19 interact with the lateral surfaces of the wheel. 
     The spring 10 can be interposed between the frame 2 and the second end 16, so as to keep the inclined planes 18 and 19 raised with respect to the lateral surfaces or to the surfaces adjacent to the rolling surface of the underlying wheel 6 during normal sports practice. 
     It has thus been observed that the device has achieved the intended aim and objects, allowing the skater to stop the skate or reduce its speed, while preserving the wheel from wear, since it is the roller, which may also be made of very hard material, that interacts with the ground. Furthermore, the fact that the rotation of the element 7 makes the inclined planes interact with the lateral surfaces of the wheel also allows the shifting the center of gravity of the braking action below the foot of the skater, thus improving balance and braking control and increasing safety. 
     Naturally, the materials of which the elements of the device are made, as well as the dimensions of the individual components of the device, may vary according to the requirements.