Patent Publication Number: US-8986166-B2

Title: Electromechanical system for selecting weights in fitness station weights towers

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is the National Stage entry of international application No. PCT/BR2010/000159, filed May 17, 2010, and claims the priority of Brazil Application No. PI 0901645-7, filed May 20, 2009, the entire specifications, claims and drawings of which are incorporated herein by reference. 
     BACKGROUND 
     1. Field 
     The present specification refers to an electromechanical system for selecting weights in a fitness station weight tower and, more specifically, an electromechanical system which coupled to a fitness station weights tower acts in conjunction with a combination of fractional weights to harness to the traction cable of the fitness station the total value of the weight selected by the user. 
     2. Introduction 
     As those skilled in the art are aware, fitness station weight towers have various unit weights stacked, which may, in whole or in part, be lifted inside the towers by central vertical steel cables, tractioned by active members of the fitness station driven by the user. Selecting the weights to lift can be obtained by inserting a horizontal pin which traverses a hole existing in each weight in correspondence with a sequence of holes of a tenon that extends below the lower weight and fastens superiorly to the steel cable. A weight selected by the pin carries with it all the weights above it. 
     The most modern towers have electromechanical systems for selecting weights, commanded by a panel fixed to the fitness station. 
     Generally, fitness stations present a proximate tower, which by way of steel cables, linked to levers, pulleys and cams of the respective station, promotes the mechanical interlink between the contact accessory, bars, hand control and other devices, offered to the user for a certain exercise and the grouping of weights selected, which are mounted on the tower. 
     This grouping of weights is comprised by the stacking of unit mass plates, lifted inside the tower by means of a steel cable, coming from the fitness station, which is fastened at the center, on a cursor guided by internal columns. A central vertical rod of the cursor traverses all the weights below the cursor, in vertically-aligned holes, and this rod has, at the level of each weight plate, holes or grooves so that the pin, driven by the user, traverses holes or grooves of each weight plate, engaging one of them to the vertical rod. Accordingly it is possible to select as many weight plates as it is desirable to lift, as the plate engaged to the vertical rod lifts all those above it. 
     As those skilled in the art are aware as are those who practice this type of physical activity, physical fitness exercises obey a weight alteration sequence, comprised by a specific program indicated by the trainer. The user or participant, therefore, resorts countless times to change of position of the selection pin in the stack of weights. 
     However, the tower housing the grouping of weights cannot always be near the user due to the range of movements of the arms, levers, and so frequent changes of weight may become inconvenient. 
     In this sense, means thus arose for selecting weights with the assistance of electric motors or solenoids, commanded by a panel in a position that is easy to reach by the user. Among the various means created, some move pins in and out of the weights to engage them with the central vertical rod, which raises the weight chosen plus those above it. The cursor, which is a guide for vertical movement, and which operates with the rod and the steel cable, is used to accommodate the system for selecting weights, by means of an electric motor or solenoids. 
     Regardless of the kind of drive and selection of the weights, it is also known that the descent of these weights to the lower stopper of the tower, or on the weights that were not selected to be lifted, may cause a mechanical shock, if the user quickly releases their handling. Another way in which this not always smooth descent may occur is potentially when there a rupture of the steel cable, causing a free fall movement of the selected plates, which violently crash down on the inoperative plates resting on the base of the tower, or crash directly onto the latter. With these inadvertent and/or accidental shocks, solenoids and motors, as well as sensors and other electromechanical devices become susceptible to damage with the occurrence of repetitive shocks. 
     It is, therefore, one of the objectives of the present invention to provide an electromechanical system for selecting weights in fitness station weights towers that seeks to solve the problem of defects due to mechanical shocks, in which electromechanical mechanisms and other electric devices are incorporated to the cursor and to the stack of weights. 
     Another objective of the present invention is to provide an electromechanical system for selecting weights in fitness station weights towers which being electromechanical do not have the electrical wiring that accesses the motor, or solenoids or associated electrical devices, and which communicates to the tower with the station command panel, hanging on a part in movement. 
     SUMMARY 
     These and other objectives and advantages of the present invention are achieved by an electromechanical system for selecting weights in fitness station weights towers brought into effect by a tower, formed by vertical columns, upper crosspiece, lower base, with a stack of unit weight plates, with vertical guides inside the tower, fixed to the upper crosspiece and to the base, with the stack of plates headed by a cursor which in the center fastens to the steel cable that lifts the weights, this cursor having a central rod projected downwards, penetrating into central holes of all the plates and provided with means of selective engagement to any plate, represented by a vertical screw, disposed in the hollow center of the rod and mounted thereon by bearings situated at the upper and lower parts of the rod. According to the present invention the base of the tower is hollow, and has installed on its inside an electromechanical mechanism for selecting weights, comprised by an electric motor, at least a belt, and at least a pulley, mounted by bearing to a shaft fixed to the lower face of the base, collinearly to the center of the rod and screw, this pulley having, in the upper part, a selective engagement mechanism with the lower end of the screw to actuate only when the rod is totally lowered, with the plates resting on the base of the tower. 
     An electromechanical system for selecting weights in fitness station weight towers, wherein a vertical hollow rod, fixed to the cursor which fastens to the steel cable, which lifts the plates of unit weight, extends traversing central holes of these plates, traversing the upper wall of the base of the tower, which is hollow, this rod having a rotating shaft or screw that moves the weight selector upwards and downwards, mounted on the rod by bearings, and projecting below this bearing where it has at the end radial teeth that encase between protrusions existing in a circular low relief of a pulley, which is mounted on a bearing whose shaft is collinear to the rod and fixed to the lower face of the base, this pulley having a channel for a belt, driven by an electric motor fixed to the base; a rod upon traversing the upper wall of the base has a circular low relief in which there is encased a latch propelled against the low relief by a spring and which may be disengaged by a trigger that can be pulled by an electromechanical linear actuator, with a sensor indicating the position of the latch; the pulley has a disk with recesses to drive a sensor fixed to the base by a support. 
     It is understood that other aspects of the invention will become readily apparent to those skilled in the art from the following detailed description, wherein various aspects of the present invention are shown and described by way of illustration only. As will be understood, the present invention is capable of other and different variations and its several details are capable of modification in various other respects, all without departing from the scope of the invention. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not as restrictive. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate various example implementations consistent with aspects of the invention, and, together with the description, serve to explain the principles thereof: 
         FIG. 1  depicts a raised front view of a weights tower, in accordance with some aspects of the present invention; 
         FIG. 2  is a raised side view of the weights tower, in accordance with some aspects of the present invention; 
         FIG. 3  is a vertical cut view of the lower part of the tower, passing through the center of the stack of weights, containing a lesser quantity of weight plates to facilitate understanding, and for the purpose of illustration without any limitative character, only a set of four weight plates is being presented, in accordance with some aspects of the present invention; and 
         FIG. 4  is a top view of the motor combination and drive pulley, in accordance with some aspects of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     As shown in the figures, an electromechanical system for selecting weights in fitness station weights towers may include a weights tower (see  FIGS. 1 and 2 ) that consists of a structure formed by vertical columns  1 , upper crosspiece  2  and lower base  3 . The system may include a stack of weights formed by unit weight plates  4  on top of each other, and guided in vertical movement by guides  5 . The guides  5  are tubes or vertical bars fastened to the crosspiece  2  and to the base  3 . A cursor  6 , which is a board, is disposed on the stack of plates  4 , with tubes wherein guides  5  are encased. The system further includes a central support  7  where the steel cable  8  of the tower is fastened by a screw or nipple  9 . 
     The cursor  6  centrally has a vertical rod  10  that traverses central holes of all the plates  4 , and the device for selecting weights is incorporated into the rod  10 , as shown in  FIG. 3 . 
     According to the present invention, selective engagement, illustrated in  FIG. 3 , is performed by the expansion of one or more pairs of pins  11 , mounted in radial holes of the rod  10 , at the level of the center of each plate  4 , on which there are radial holes  12  that can receive the encasement of the pins  11  which were displaced partially outside the rod  10 , at the level selected for the engagement. 
     The expansion of the pins  11  at a certain level is carried out by a nut  13  with conic ends, mounted on a vertical screw  14 , and disposed in the center of a central axial hole of the rod  10 . The screw  14  may be mounted to the rod by bushings or bearings  15 . Turning the screw  14  causes the nut  13  to go up or down, to alter the quantity of plates  4  to be raised. Conic ends of the nut  13  outwardly push the pins  11 . Before being pushed outwardly by the nut  13 , the pints  11  do not extend into the holes  12  of the plates  4 . After being pushed outwardly by the nut  13 , the pins are encased in holes  12  and remain encased in the radial holes of the rod  10 . Therefore, the selected plate  4  becomes secured to the rod  10  and can be lifted by the steel cable  8 , carrying with it the plates  4  that are above them. The remaining plates below the selected plate rest on the base  3  of the tower. 
     Generally, to move the screw  14  inside the rod, or another selected plate engagement device  4 , an electric motor or solenoids are used, installed in the cursor  6  which has a rod  10 , normally mounted on the central support  7  of this cursor, and the electromechanical drive combination accompanies the rising or lowering of the weights, with its electric communication to the command panel by way of a flexible electric cable hung and attached to the connector at the top of the tower in order to avoid rupture by stretching. 
     This construction subjects the electromechanical devices to shocks, when the weights are lowered with speed by the user of the fitness station, and it is knowingly very difficult to construct these devices with resistance to repetitive mechanical shocks and to fatigue. In contrast, if there is a rupture of the steel cable while the weights are suspended, the shock due to free fall, with hardly any damping, may mean the loss of the electromechanical devices. Another undesirable condition consists of involuntary driving of the weight selector while they are suspended, causing release of plates in free fall on the inside of the tower, which may occur due to deficiency in the electro-electronic command system of the panel. 
     The present invention presents a solution for the problems cited above, and introduces total security in handling the weights by electromechanical means. 
     As can be seen in  FIG. 3 , the base  3  of the tower is hollow, and installed therein is the mechanism for selecting weights. This base has in the upper part a hole that is traversed by the lower part of the rod  10 , where it has a circumferential recess  16 , in which there is encased a latch  17  similar to that of a door lock, with a spring  19  inwardly pressing the low relief  16 , and horizontally mobile, having a trigger  18  which can be pulled by an electromechanical linear actuator  20 . The lower end of the rod  10  is conic to facilitate the displacement of the latch  17  whenever this rod penetrates into the hole of the base  3  and arrives at the hollow part thereof, and at the same end there is located the bearing  15  of the screw  14 . Projecting outwardly of the rod  10 , the screw  14  has protruding radial teeth  21  at the end. 
     As shown in  FIG. 4 , in a concentric manner to the rod  10  and therefore, concentric to the screw  14 , the base  3  has, on the inner face, a fixed shaft  22 , with a bearing  23  that permits the turning of a pulley  24 , which has a circular reentrancy  25 , where there can be housed the end of the screw  14  with its teeth  21 , and where it has protrusions  26  pointing inwardly, providing rotating drag movement between pulley  24  and screw  14 . The pulley  24  has, on its outer circular face a channel for a belt  27  and a disk  28  with recesses  29  or holes for driving an optical or inductive sensor  30  mounted on a support  31  of the base  3 . 
     The pulley  24  is driven, by way of the belt  27 , by an electric motor  32  mounted on the inner wall of the base  3  by a cushion  33  shock absorber. A latch  17  and its trigger  18  have their position detected by an inductive or electromechanical sensor  34  fixed to or incorporated in the linear actuator  20 . The information of this sensor  34  is taken to the command panel of the weight selector, situated in the fitness station. 
     The rod  10  has, below the level of the lower engagement pins  11  a special pin  35  which can be displaced when the nut  13  arrives at its level, the base  3  having an inductive sensor  36  situated at a level that coincides with the level of this special pin  35  when the rod is at its lowest point in the tower. The sensor  36  perceives when the special pin  35  is outjutting and relays the information to the command panel of the fitness station, which interprets the initial position of the nut  13 , resetting the turn count of the screw  14  so that the other turns place it exactly facing the pins  11  at the level of the plate  4  the user wishes to engage. 
     The number of turns of the screw  14  made, propelled by the motor  32 , belt  27 , pulley  24  and the interlocking of the teeth  21  with the protrusions  26  of the pulley  24 , is counted by the passage of the recesses  29  of the disk  28  facing the sensor  30 , which sends electrical signals to the command panel of the fitness station. 
     When the rod  10 , jointly with the plates  4  selected rises, tractioned by the steel cable  8 , the teeth  21  of the screw  14  disengage from the protrusions  26  of the circular reentrancy  25  of the pulley  24 , fixing the inoperative screw  14 , whereby guaranteeing the engagement status of the rod  10  with the selected plate  4 , not producing any accidental effect on the drive of the motor  32 . 
     When the rod  10  descends to its lowest level, the latch  17  encases in the circular low relief  16  thereof, preventing it from rising again if the steel cable  8  tries to re-lift it. 
     The latch  17 , in turn, is kept in locked position while the command panel of the fitness station carries out, by way of the motor  32 , belt  27 , pulley  24  engaged by the protrusions  26  to the teeth  21  of the screw  14 , the change in the selection of plates  4  to be lifted, after which the command panel drives the linear actuator  20 , which pulls the trigger  18 , and the latch  17  abandons the low relief  16  releasing the rod  10  to rise again. 
     At the same time, the sensor  34  advises the command panel of the drive state of the latch  17 , to authorize the drive of the motor  32  only with locking of the rod  10 . 
     The above-described electromechanical system for selecting weights in fitness station weights towers provides following advantages:
         it places the electromechanical drive system for selecting weights on a fixed base of the tower, protected against mechanical shocks or potential free fall;   it allows movement for selecting weights only when all the plates are in rest position, on the base of the tower;   it prevents the rod and the weight plates from being raised when the electromechanical combination for selecting weights is in operation; and   it does not require electric communication cables between the cursor  6 , which accompanies the weight plates and the tower.       

     While the present invention has been described in connection with preferred aspects, it will be understood by those skilled in the art that variations and modifications of the preferred aspects described above may be made without departing from the scope of the invention. Other aspects will be apparent to those skilled in the art from a consideration of the specification or from a practice of the invention disclosed herein.