Patent Publication Number: US-7591771-B2

Title: Apparatus and method for facilitating the safe lifting of free weights

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
   This application claims priority benefit of identically titled Provisional Application Ser. No. 60/637,952, filed Dec. 20, 2004, and such Provisional Application is incorporated by reference herein. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention is broadly concerned with an apparatus for facilitating safe free-weight exercises in order to minimize the possibility of injury to the weight lifter or adjacent equipment. More particularly, the invention is concerned with such safety apparatus, as well as overall free-weight exercise devices and corresponding methods, wherein a bar-sensing apparatus is preferably employed, including a plurality of weight position sensors located to monitor the weight during lifting thereof, as well as a processor for calculating a parameter related to the velocity of the weight. The processor is also coupled with extensible supports, which are operated in the event that the lifter loses control of the weight. 
   2. Description of the Related Art 
   Free-weight enthusiasts typically perform lifting exercises in a supine position on a padded weight bench or while standing. These exercises involve raising and lowering a barbell weight through a series of repetitions, and very often the lifter will continue the repetitions to a point where he or she can no longer continue them. A common problem with this type of lifting regimen is that the lifter may lose control of the barbell, with the result that it may injure the user or harm adjacent flooring or equipment. 
   In light of this, it is common for a lifter to enlist the aid of a “spotter,” who monitors the lifter&#39;s exercise repetitions and is available to “catch” the barbell in the event that the lifter begins to lose control. Notwithstanding the presence of a spotter however, the same types of problems can occur, particularly if very heavy weights are involved. Furthermore, the need for a spotter makes it impossible for a weight lifter to perform this and other types of lifting exercises alone. 
   U.S. Pat. No. 6,746,379 describes a bench press apparatus making use of assist hydraulic cylinders which can be actuated by the lifter through a foot pedal or similar expedient. However, the type of apparatus described in this patent does not fully solve the weight lifter&#39;s dilemma because the lifter may be unable to timely initiate operation of the support cylinders, especially where the barbell is dropped. 
   The art is replete with other types of barbell systems and weight lifting devices. See, U.S. Pat. Nos. 4,822,034; 5,082,259; 6,774,320; 6,436,016; 5,755,823; 5,603,677; and 5,203,425. However, none of these references fully address or solve the problems outlined above. 
   SUMMARY OF THE INVENTION 
   The present invention overcomes the noted safety issues and provides a safety assist device for use with an elongated weight bar. The assist device comprises a pair of elongated, spaced apart arms oriented to permit the weight bar to move along at least a portion of the length thereof; and a bar-sensing apparatus including a plurality of sensors located along the length of at least one of the arms. The sensing apparatus is operable to determine at least one parameter related to the velocity of the bar as the bar moves along the length of the arms. A support is also associated with each arm respectively and includes a shiftable, bar-supporting element. The supports are operably coupled with the bar-sensing apparatus in order to shift the elements to a bar-supporting position in the event that the at least one velocity-related parameter is outside of a predetermined parameter range. 
   In preferred forms, the arms are upright and present guide slots for receiving the ends of the weight bar, and the sensors are faced along the length of the upright arms. The sensors are coupled with a digital processor programmed to calculate the selected velocity parameter, based upon the sensed positions of the bar during movement thereof. The preferred extensible supports are in the form of fluid-actuated piston and cylinder assemblies, most preferably hydraulic or pneumatic cylinder assemblies. 
   The methods of the invention involve providing a weight to be lifted and allowing a user to repetitively raise and lower the weight. The weight is monitored during the raising and lowering thereof, and at least one parameter related to the velocity of the weight is determined during such monitoring. In the event that the determined parameter falls outside of a predetermined parameter range, a weight-supporting element is moved into engagement with the weight in order to at least partially support the weight apart from the user. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of a free-weight bench in accordance with the invention, having the safety assist device as a part thereof; 
       FIG. 2  is a fragmentary perspective view of a portion of the bench of  FIG. 1 , illustrating one of the support cylinders in its lowered position; 
       FIG. 3  is a fragmentary perspective view similar to that of  FIG. 2  but illustrating the support cylinder in an elevated position; and 
       FIG. 4  is a block diagram illustrating the operative connection of the components of the safety assist device. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Turning now to the drawings, a free-weight bench  10  is illustrated in  FIG. 1  and includes a safety assist device  12  (see  FIG. 4 ) of the invention. Broadly speaking, the bench  10  includes a frame assembly  14 , a barbell weight  16  supported within the device  12 , and a padded user bench  17 . 
   As illustrated in  FIGS. 1-3 , the frame assembly  14  includes a rectangular floor-engaging section  18 ; upwardly extending, oblique support members  20 , 22 , 24 , 26 ; and opposed struts  28 , 30 . The frame assembly  14  supports a pair of spaced apart, bifurcated arms  32 , 34  forming a part of safety assist device  12  and interconnected by an uppermost rail  36 . The arms  32 , 34  present corresponding elongated vertical guide tracks or slots  38 , 40 . 
   The barbell weight  16  is itself entirely conventional and comprises an elongated weight bar  42  adapted to receive endmost weights  44 . As best seen in  FIG. 1 , the bar  42  passes through and is vertically shiftable along the length of the arm slots  38 , 40 . As is readily apparent, the barbell weight  16  is designed to be repetitively raised and lowered by a user (not shown) lying in a supine position on bench  17 . In an alternative implementation, the bench  17  can be removed, and the user can lift the weight  16  without use of the bench  17 , such as if the user were performing squats. 
   The safety assist device  12  includes, in addition to the arms  32 , 34 , bar-sensing apparatus  45 , as illustrated in  FIG. 4 . The bar-sensing apparatus  45  includes a plurality of sensors  46  positioned along the length of each arm  32 , 34  in spaced relationship to each other, as illustrated in  FIGS. 1-3 . While a variety of sensors can be used in this context, conventional infrared sensors are preferred. The device  12  further includes a support  47  associated with each arm  32 , 34  respectively and including a shiftable, bar-supporting element  56 . In preferred form, the supports  47  comprise a pair of fluid-actuated piston and cylinder assemblies  48 , 50  located in an upright orientation adjacent each arm  32 , 34 . The assemblies  48 , 50  may be hydraulic or pneumatic, and each include an extensible piston rod  52 , 54  surmounted by the bar-supporting element, which is preferably a weight bar-engaging and supporting pad  56 . The cylinder assemblies  48 , 50  are operable to shift the bar to a plurality of locations along the length of arms  32 , 34 , as discussed in more detail below. 
   The operative connection between the components of the safety assist device  12  is schematically illustrated in  FIG. 4 . That is, in preferred forms, the bar-sensing apparatus  45  comprises the sensors  46 , and a digital processor  60  equipped with a memory module  62 . As shown, the sensors  46  are operably connected to the processor  60 , and the processor  60  is also connected to conventional fluid pumps and valves (not shown) forming a part of the piston and cylinder assemblies  48 , 50 , in order to actuate the latter. The processor  60  is programmed so as to receive information from the sensors  46  and to calculate at least one parameter related to the velocity of the bar  42  as it moves along the length of the arms  32 , 34 . This velocity parameter is preferably selected from the group consisting of velocity, instantaneous velocity, average velocity, acceleration, instantaneous acceleration, and average acceleration. Moreover, the processor  60  is programmed to operate the cylinder assemblies  48 , 50  in the event that the calculated velocity parameter is outside of a predetermined range for that parameter. 
   As also shown in  FIG. 4 , an optional input/display device  64  and a load sensor  66  may be connected to the processor  60 . The input/display device  64  allows the user to input user information such as user identity, date, weight amounts, and exercise regimen. The display  64  allows the user to track his or her progress during and after an exercise session. The load sensor  66  may be coupled to the respective piston cylinder assemblies  48 , 50  for automatically determining the weight load being lifted. 
   In use, the user selects a weight to be lifted by attaching the appropriate weights  44  to the outboard ends of the weight bar  42 . If the input/display  64  is employed, user information may be inputted to the processor  60 . The user then begins lifting the barbell weight  16  within the slots  38 , 40 ; this typically involves a regimen where the barbell weight  16  is raised and lowered repetitively. As long as the user maintains proper control of the barbell weight  16 , the safety assist device  12  does not come into play. However, if for example, the user loses control of the barbell weight  16  when in a raised position, the barbell will begin to rapidly descend within the slots  38 , 40 . This is immediately detected by virtue of the fact that the bar  42  passes the sensors  46 , allowing the processor  60  to determine a velocity parameter such as acceleration. The determined parameter is then compared with predetermined limits in a look-up table within memory module  62 . If the parameter is outside of such limits, the processor sends an operating signal to the piston and cylinder assemblies  48 , 50 , causing the piston rods  52 , 54  thereof to immediately extend to a point where the pads  56  engage the underside of bar  42  and thereby at least partially support the weight of the barbell weight  16  apart from the user. Thus, the uncontrolled downward descent of the weight  16  is arrested so as to prevent injury to the user. 
   In another scenario, the user may be lifting the weights  16  and nearing the end of his or her strength, with the effect that the upward movement of the bar  42  becomes very slow. This low velocity movement of the bar is again detected by the sensors  46 , and such information is transmitted to the processor  60 , thus causing the cylinder assemblies  48 , 50  to extend and support the weight  16  before the user loses control thereof. 
   The present invention is susceptible to many variations and alternatives. For examples, the arms  32 , 34  need not be rectilinear but may be arcuate; the sensors  46  may be of various types; the supports  47  could be stepper motors or other mechanical devices in lieu of fluid actuated cylinder assemblies  48 , 50 ; and the pads  56  may be secured to the ends of bar  42 , in which case the assemblies  48 , 50  would be operated during raising and lowering of the bar  42  to negate the effect of the interconnection between the assemblies  48 , 50  and the bar  42 .