Abstract:
A gymnastic machine ( 1 ) comprising a frame ( 10 ) supporting a first actuating device ( 40 ) provided with at least a pair of first levers ( 102 )( 104 ), each of which presents a respective implement ( 112 )( 116 ) suitable to act as user interface; a load unit ( 300 ) being provided in connection with the first levers ( 102 ) so as to dissipate power applied to each implement ( 112 )( 116 ) in a proportion definable at will; said load unit ( 300 ) being designed to maintain the first levers ( 102 )( 104 ) in phase opposition; second actuating devices ( 50 ) of magnetic kind being associated with the load unit ( 300 ) to bring and maintain the first levers ( 102 )( 104 ) at rest in a neutral position so as to prevent stopping conditions.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a gymnastic machine. In particular, the present invention relates to a gymnastic machine provided with a load group that can be actuated cyclically. In more detail, the present invention relates to a gymnastic machine comprising a load group that can be actuated cyclically through at least one actuating member designed to be movable along an annular path. 
     BACKGROUND TO THE INVENTION 
     In the sector of gymnastic machines for cardiovascular training, the use is well known of load groups provided with at least one rotating mechanical member carried by a frame of the machine and designed to act as dissipater of power exerted by a user on an implement coupled to the mechanical member directly or indirectly, through the interposition of a transmission device. Such a mechanical member, generally comprising a flywheel, presents a significant mass, to make the power exchange with the user easier during the machine operation, and, at the end of the training exercise, maintains its condition of rotary motion until the inertial torque associated with the flywheel is balanced by the resistant torque deriving from the combined action of the frictions present in the pair of members in relative motion, and of the inertia of the members usable for the actuation. It is easily understood that the flywheel stops when the inertial torque, linked to the rotating mass thereof, becomes lower than the resistant torque typical of the movable members of the machine that are connected to the flywheel. When this condition occurs, the flywheel is preferably arranged in a position, to which a given arrangement of the movable members of the machine corresponds, that can match with a stopping condition that must be released to allow starting of the machine from the rest operating condition. In particular, to release the machine it will be necessary to actuate contrarily the members used for the actuation and it can require great efforts for users with athletic preparation of any level. Obviously, such a problem occurs also in machines where the resistant/load group is of the electromechanical type. 
     In view of the above description, the problem of having available a machine for cardiovascular training, where the condition of mechanical block can be avoided, is currently unsolved, and represents an interesting challenge for the applicant, in order to facilitate these types of training through mechanical or electromechanical machines. 
     In view of the situation described above, it would be desirable to have available an economical safe gymnastic machine which, in addition to enabling to limit and possibly to overcome the typical drawbacks of the prior art illustrated above, could define a new standard for the cardiovascular training methods. 
     SUMMARY OF THE INVENTION 
     The present invention relates to a gymnastic machine. In particular, the present invention relates to a gymnastic machine provided with a load group that can be actuated cyclically. In more detail, the present invention relates to a gymnastic machine comprising a load group that can be actuated cyclically through at least one actuating member movable along an annular path. 
     The object of the present invention is to provide a gymnastic machine for executing gymnastic exercises, which allows the disadvantages described above to be solved, which is practical in use and economical, and which is suitable to satisfy a plurality of requirements that to date have still not been addressed, capable of modifying the current market of the gymnastic machines and the training techniques, and therefore suitable to represent a new and original source of economic interest. 
     According to the present invention, a gymnastic machine is provided, whose main characteristics will be described in at least one of the appended claims. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       Further characteristics and advantages of the gymnastic machine according to the present invention will be more apparent from the description below, set forth with reference to the accompanying drawings, which illustrate at least one non-limiting example of embodiment, in which identical or corresponding parts of the device are identified by the same reference numbers. In particular: 
         FIG. 1  is a side elevation view with some parts removed for the sake of clarity of a machine according to the present invention; 
         FIG. 2  is a view in enlarged scale and with some parts removed for the sake of clarity of a portion of  FIG. 1 ; and 
         FIG. 3  is a view in enlarged scale and with some parts removed for the sake of clarity of a portion of  FIG. 2 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     In  FIG. 1 , number  1  indicates, in its entirety, a gymnastic machine validly usable for executing an aerobic gymnastic exercise, and therefore for training the cardiovascular system. It should be noted that, for the sake of practicality, without however limiting the protective scope of the present invention, the gymnastic machine  1  is of the type already described with reference to the Italian patent application No. RA2008A000045, whose description and mosaics shall be considered an integral part of the present description for saving text and drawings, when indicated, even if the reference numbers used to indicate identical parts different from each other for description requirements. 
     With reference to  FIG. 1  again, the machine  1  comprises a frame  10 , an actuating device  40  provided with a pair of first levers  102 , each of which is supported by the frame  10  through the interposition of a second lever  104 , pivoted on the frame  10  and through a first flexible member  106 , better described below, which supports the first lever  102  in intermediate position through an articulated connection  114 . 
     Each first lever  102  is therefore connected to the frame  10  so as to oscillate similarly to a connecting rod of a four bar linkage relative to the frame  10 . Each first lever  102  presents an end portion  108  shaped to couple with the lever  104 ; each first lever  102  furthermore presents a free end  110  at opposite side from the end portion  108  and provided with a footrest  112 . In view of the above description, each footrest  112  is arranged substantially overhanging behind the connection  114  in  FIG. 1 . Each second lever  104  presents, at opposite side relative to the end portion  108  of the corresponding first lever  102 , a knob  116 , that is tiltable relative to the frame  10  in view of the above description and can be held by a user for moving the upper limbs. The machine  1  furthermore comprises a load device  300  arranged at the side of the end portion  108  of the first lever  102 , without however limiting the protective scope of the present invention. This load device  300  is provided with a flywheel  320  carried by the frame  10  in a freely rotatable manner around a given substantially horizontal pivot axis  30 , as shown in  FIG. 1 . This flywheel  320  is kinematically connected with the actuating device  40  through a transmission  200 , already described with reference to the patent application No. RA2008A000045 and functionally recalled hereafter with the minimum required detail, for the sake of practicality. In addition to the first flexible member  106  and to the respective return members, not described for the sake of practicality, this transmission  200  furthermore comprises, for each first lever  102 , a crank  322 , rigidly coaxially connected with the flywheel  320 . The transmission  200  furthermore comprises, for each crank  322 , a second flexible member  24 , already known from the patent application No. RA2008A000045 and connected with the corresponding first flexible member  106  through a joint  26 , which is associated with the frame  10  and is already known from the same patent application No. RA2008A000045. The two cranks  322  are mutually opposite, i.e. they are in phase opposition, so as to put the flywheel  320  into rotation under the thrust of the two footrests  112  through the first and second flexible members  106  and  24 . The particular arrangement of the cranks  322  maintains therefore the levers  102  constantly in phase opposition. 
     In view of the above description, in the machine  1  taken herein as a reference to illustrate an embodiment of the present invention, the footrests  112  are constrained to move along an horizontally elongated elliptical trajectory, extending vertically for a limited width, and therefore the machine  1  can be used for walking or running training. 
     As it is well known, the flywheel  320  comprises a circular member with significant mass, whose object is, in use, to store rotational kinetic energy produced by actuating the footrests  112  and/or the knobs  106  to smooth the execution of the gymnastic exercise performed through the machine  1 . The flywheel  320  acts therefore as a power dissipater member until the rotation speed in the starting phase of the machine  1  achieves a substantially constant value and, during the use thereof under steady-state conditions, it acts as accumulated power “reserve” to facilitate preservation of a steady-state operation. The presence of the flywheel  320  therefore makes the stop times of the machine  1  longer, in phase of conclusion of the exercise. 
     It should be noted that a stopping condition of the machine  1  can occur when the belt  24  is arranged according to the vertical, the cranks  322  are aligned with the belt  24  and the first levers  102  are arranged in a scissor manner, in the respective top and bottom dead centres. 
     The loading device  300  furthermore presents a power dissipating member of the adjustable type comprising an electromagnetic brake  340  carried by the frame  10  and provided with a rotating disk  342  mechanically connected to the flywheel  320  in an angularly fixed manner through a further belt transmission  400  with parallel axes. The loading device  300  therefore combines partially fixed and partially adjustable mechanical characteristic, respectively set by the flywheel  320  and by the brake  340 . The transmission  400  can be single- or multi-stage. In particular, although without limiting the protective scope of the present invention, in the attached drawings this transmission  400  is double-stage. The object of this transmission  400  is to modify the kinematic parameters of the disk  342  of the brake  340  relative to those of the flywheel  320  and of the first levers  102 , responsible for the actuation of all the moving parts of the machine  1  to improve the performances of the brake  340 . 
     The machine  1  furthermore comprises an anti-stopping device  50  associated with the flywheel  320  and comprising at least one magnet  52  carried by the flywheel  320 . In particular, with reference to  FIG. 3 , the anti-stopping device  50  comprises a pair of movable magnets  52  carried by the flywheel  320 . These magnets  52  are diametrically opposite, analogously to the cranks  322 , and are generally displaced relative to a quadrature condition with these latter for reasons that will be more apparent below. This anti-stopping device  50  furthermore comprises a fixed magnet  54 , carried by the frame  10  in a position facing each movable magnet  52 . In particular, the frame  10  carries the fixed magnet  54  at a height substantially identical to the distance of the trace of the axis  30  in  FIG. 1  relative to a pavement PV, on which the machine  1  stands, so that the two movable magnets  52  are substantially equidistant from the fixed magnet  54  when the flywheel  320  is arranged with the cranks  322  substantially horizontal, in an arrangement visible in  FIG. 1  and, in more detail, in  FIG. 3 . In view of the above description, the movable magnets  52  and the fixed magnet  54  are arranged at a substantially identical radial distance from the pivot axis  30  of the flywheel  320 , so as to exert on the flywheel  320  a torque of magnetic nature suitable to constrain the flywheel  320  to take a given operating position relative to the frame  10 . To achieve this, the movable magnets  52  and the magnet  54  present homologous opposite magnetic poles and the magnetic repulsion force exchanged between the homologous poles of each magnet  52  and of the magnet  54  is maximum when these magnets face each other. This repulsion force decreases significantly in case of even minimum displacement between a magnet  52  and the magnet  54 , i.e. the case where the magnetic torque on the flywheel  320  appears. This explains why the arrangement of the magnets  52  on the flywheel  320  in not in quadrature with the cranks  322 , as, in that case, the repulsion force could be maximum but the stopping condition could not be overcome easily due to the condition of a magnet  52  facing the magnet  54 . Therefore, each crank  322  is normally displaced relative to the magnet  52  by an angle different than 90°. A confirmation of this situation can be obtained graphically in  FIG. 2  and, in enlarged scale, in  FIG. 3 , observing the straight line L and the angle with the straight line connecting the centres of the two movable magnets  52 , and the inclination of the flexible member  24  relative to a vertical direction, in particular in  FIG. 2 . These figures show a situation of down time, wherein, due to the interaction between the adjacent magnets  52  and  54 , the cranks  322  move away from the vertical position, thus making impossible to detect the stopping condition. 
     Obviously, the choice of the movable magnets  52  and of the fixed magnet  54  is made to have available, when the movable magnets  52  and the fixed magnet  54  are slightly displaced from each other, a sufficient torque to move the cranks  322  from the stopping position and, consequently, the first levers  102  from the scissor position. 
     To this position of the cranks  322  can therefore correspond any rest position of the first levers  102 , provided that it is different from the scissor arrangement of the first levers  102  visible in  FIG. 1 . 
     In view of the above description, the anti-stopping device  50  can be interpreted as a second actuating device, that acts when there is no external load acting on the first levers  102  or on the second levers  104 . 
     The use of the gymnastic machine  1  described above is readily apparent in view of the above description and requires no additional explanations. 
     Lastly, it is apparent that modifications and variants can be made to the gymnastic machine  1  described and illustrated herein, without however departing from the protective scope of the present invention. 
     For instance, it is easily understood that the movable magnets  52  and/or the fixed magnet  54  can be of the permanent type or they can be electromagnets powered by an electric current adjustable in a known and therefore not shown manner, so as to produce a magnetic field with intensity variable also instant by instant, to avoid stopping conditions of the first/second levers  102 / 104  even with internal friction between the moving members of the machine  1  greater than the project conditions. For this purpose it should be advisable to complete the outfit of the gymnastic machine with a power-supply unit, no-load resistance sensors and an electronic unit to which connect the sensors and the magnets so as to vary adequately the parameters of the electric current to supply to these latter. 
     In view of the above description it is clearly apparent that each gymnastic machine  1  structured as described above is suitable to be used, starting from the rest condition, also by deconditioned users or users who could feel awkward in performing opposite actuation operations of the machine they want to use to perform a cardiovascular training session.