Abstract:
An improved weight exercise apparatus having an interlocking grip bar and rotationally removable weight plates. A weight plate is attached to a socket on the grip bar and can be interlocked with additional weight plates using a simple insert and twist motion. The grip bar does not extend beyond the attached weight plates making the apparatus ergonomically friendly and aesthetically pleasing. The invention restricts the movement of interlocked weight plates to limit rattle-type noise typical of loose weights on a barbell and includes a latching mechanism to prevent a weight plate from being accidentally disconnected.

Description:
FIELD OF THE INVENTION 
     The present invention relates to an adjustable weight apparatus with modular interlocking components. 
     BACKGROUND OF THE INVENTION 
     The practice of exercising with weights is well known, and is commonly used to increase the strength and tone of muscles in the body. As such, the fitness equipment market has a preponderance of barbells, dumbbells, and other types of weight resistance equipment. 
     When exercising with weights, it is often desirable to change the amount of weight being used during an exercise program. A variety of fixed weight equipment is available, but a suitable selection of such equipment requires a lot of room for use and takes a good deal of space for storage. 
     Adjustable weight equipment is also available where weights may be added or removed from an apparatus. The process for changing weights, however, is often complicated and time consuming. For example, as described in U.S. Pat. No. 4,529,197, weight changes are made by removing and replacing a protruding locking collar on a grip bar each time weights are added or removed. In addition to being time consuming, the procedure may require a special tool, and can be difficult to implement. 
     In other types of adjustable equipment, weights are changed using a threaded connector as described, for example, in U.S. Pat. No. 5,464,379. Threaded connectors have several disadvantages. They may bind, become difficult to remove, and require tightening, which is dependent on the strength of the user. In addition, the weights may become loose during an exercise and may even dislodge from the bar member, causing distraction or injury. 
     Some types of apparatus have the bar or grip of a barbell or dumbbell extending beyond the weight plates, creating equipment that is larger than necessary and tending to restrict the full movement of wrists and arms. 
     In addition, most weight exercise equipment is fabricated primarily with metal parts, which tends to increase the manufacturing cost and the final cost to the consumer. 
     Accordingly, there is a need to provide an improved adjustable weight exercise apparatus that is functional, easy to use, safe from accidental disconnects, ergonomically friendly, and cost-effective. 
     BRIEF SUMMARY OF THE INVENTION 
     The invention provides an improved weight exercise apparatus comprising an interlocking grip bar assembly and weight plate assembly that can be used to form dumbbells, barbells and similar types of weight exercise equipment. 
     Weight plates of the apparatus of the invention can be added and interlocked with previously attached weight plates using a simple insert and twist motion. Accordingly, the process of changing weights does not require the removal of any collars, clamps, or similar holding devices. 
     In addition, no protruding bar is exposed at the ends of the apparatus, and the outer faces of the weight plates are flat, making the assembly safe, easy to use, and aesthetically pleasing. 
     When weight plates are interlocked to each other on the grip bar assembly, the invention provides for minimal clearances between parts, limiting any “mechanical play” between weight plates and reducing any “rattle noise”, typical of loose plates on a barbell. 
     One embodiment of the invention includes a spring or flexible material to further minimize movement between parts. 
     Each weight plate assembly of the invention includes a locking mechanism to provide safety from an accidental disconnect of a weight plate from the grip bar, or from an adjacent plate. 
     As a further safeguard against accidental disconnection, when weight plate assemblies are attached to each other, each plate covers the locking mechanism of the adjacent plate, preventing the locking mechanism from being deactivated. This feature of the invention also ensures that additional weights cannot be added to the assembly unless previously added weights are firmly locked in place. 
     The modular, interlocking, components of the invention can be fabricated by blending molded parts with metal parts, to make the assembly cost effective, attractive, and functional. 
     The novel interlocking features and safeguards of the invention are adaptable to exercise equipment, sporting goods, and to other types of apparatus where removable interlocking elements are required. 
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
     FIG. 1 is a perspective view of an apparatus of the invention; 
     FIG. 2 is a perspective view of the grip bar assembly of the invention; 
     FIG. 3 is an expanded view of the weight plate assembly of the invention; 
     FIG. 4 is a sectional view of the insert hub of the invention; 
     FIG. 5 is an illustrative view of the latching mechanism of the invention; 
     FIG. 6 is a perspective view of the weight plate assembly of the invention; 
     FIG. 7 is a view of the locking lever slot of the invention and 
     FIG. 8 is a perspective view of the compression spring feature of the invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     With reference to FIG. 1, a weight exercise apparatus  30  of the invention comprises an interlocking grip bar assembly  11  and one or more weight plate assemblies  18 . 
     The grip bar assembly  11  includes a bar or handle  10  having two ends, and a socket  12  at each end of the bar to which a weight plate assembly  18  may be attached. 
     In a preferred embodiment of the invention, the bar  10  of the grip bar assembly  11  is cylindrical in shape and of a convenient diameter to be easily grasped by hands. 
     As shown in FIG. 2, each bar socket  12  comprises a housing  13  with a cylindrical cavity  14  having a bayonet-type flange  15  with two or more radially spaced cutouts  16  and one or more stop-position shoulders  36  configured to rotationally engage corresponding bayonet-type tabs of a weight plate assembly. Although a ring-shaped housing is shown, the housing may have other shapes including, but not limited to, square or rectangular formats. 
     With reference to FIG. 3, each weight plate assembly  18  has a disc-shaped weight ring  22  with a central core  23 , and an interlocking insert hub  17 , adapted to fit into the core  23 . 
     Although a disc-shaped weight ring is shown, a weight plate may have other shapes, including but not limited to square or rectangular formats, without detracting from the functionality of the invention. 
     The insert hub  17  of the weight plate assembly  18  is cylindrically shaped with a receiving receptacle  21  on one end and a mating connector  26  on the other end. The receiving receptacle  21  has an internal cavity  19  with a circular bayonet-type flange  24 . 
     The flange  24  has two or more radially spaced cutouts  25 , and one or more stop-position shoulders  31 , adapted to rotationally engage a mating bayonet-type connector. 
     In a preferred embodiment of the invention, the flange  24  has three equally spaced cutouts. 
     The mating connector  26  of the insert hub  17  has two or more protruding bayonet-type tabs  27 , adapted to be received by the cutouts  16  of the bar socket  12  of the grip bar assembly  11  of the invention, as shown in FIG. 2, or by the receiving receptacle of another weight plate assembly. 
     The receiving receptacle and the mating connector of the insert hub are designed so that a user may connect two weight plates or a grip bar and a weight plate quickly and easily. 
     When attaching weights to the grip bar assembly, the bayonet tabs of the insert hub of a weight plate assembly are inserted into the cutouts of the bar socket flange and rotated to a stop position shoulder in the socket cavity, creating an interlock so that the devices cannot be separated until a reverse rotation is applied. 
     The hub and bar socket of the invention are designed so that accurate alignment of the bayonet tabs of the hub and the socket flange cutouts is not necessary, making the assembly ergonomically friendly to normal hand and wrist movements. 
     Similarly, when adding additional weights to a weight plate assembly, the bayonet tabs of the insert hub of the added weight plate assembly are inserted into the flange cutouts of the receiving receptacle of the existing weight plate assembly and rotated to a stop position shoulder, creating an interlock, so that the weight plates cannot be separated until a reverse rotation is applied. This exemplary feature of the invention makes adding or removing weights a quick and easy process. 
     In order to ensure that weight plates cannot be disconnected accidentally, the invention further includes a locking mechanism to prevent an unintentional reverse rotation of a weight plate assembly. 
     In a preferred embodiment of the invention, the locking mechanism is actuated automatically when the insert hub of a weight plate assembly is rotated to the proper alignment in a receiving receptacle or socket. Alternatively, the locking mechanism can be adapted to be actuated manually. 
     With reference to FIG. 4, the receiving receptacle  21  of a weight plate assembly  18  includes a locking mechanism cavity  35  containing a locking lever  20 . The lever is formed with an L-shaped extension  32  and a pin holder  37 . A dowel  33  in said cavity  35  provides for rotational movement of the lever about the longitudinal axis of the dowel. 
     The pin holder is adapted to contain a movable spring-pin assembly  28  for engaging the bottom surface  38  of the locking mechanism cavity. 
     As shown illustratively in FIG. 5, the spring-pin assembly  28  exerts pressure on the bottom surface  38  of the cavity and on the locking lever  20 . The bottom surface of the cavity is preferably ramp-shaped to keep the lever in a desired latched or unlatched position. 
     As shown in FIG. 4, the locking lever extension  32  protrudes outside the locking mechanism cavity to engage the flange shoulder of an interlocked weight plate assembly whenever the locking lever is in the latched position. 
     To release the locking mechanism, the locking lever is pushed by a finger or thumb to an unlatched position, to disengage the L-shaped extension from the attached weight plate. The plate can then be rotated in the reverse direction and released from the assembly. 
     As shown in FIG. 6, in the latched position, the locking lever  20  is aligned with the locking mechanism cavity in the receiving receptacle  21  of the weight plate assembly  18 , thereby permitting the hub of another weight plate assembly to be attached to the receiving receptacle. 
     With reference to FIG. 7, the locking lever extension is adapted to protrude through a slot opening  39  in the hub  17  when in the latched position, and clears the slot opening when in the unlatched position. 
     In operation, to create an interlock between two weight plate assemblies, or between a weight plate assembly and the grip bar assembly of the invention, the bayonet tabs of the weight plate assembly to be attached are first inserted into the cutouts in the flange of the grip bar socket or receiving weight plate receptacle. The attached weight plate is then rotated to the stop position at the shoulder of the flange, creating an interlock. When the two assemblies are in proper alignment, the locking lever is depressed to prevent a reverse rotation of the attached weight plate, maintaining the interlock. 
     In a preferred embodiment of the invention, as illustrated in FIG. 4, the spring pin assembly  28  can be relocated to a pin holder  39  on the bottom surface  38  of the locking mechanism cavity  35 , to provide automatic latching of the locking lever. In this configuration, the spring-pin assembly presses the locking lever extension into the latched position when the attached weight plate is interlocked with a receiving receptacle. 
     The interlocking elements of the invention can be formed with minimal clearances between parts to limit “mechanical play” and any “rattling noise” of the weight plates. 
     As shown in FIG. 8, a circular compression spring  34  can be added to the insert hub connector  26  to further limit movement between interlocked weight plate assemblies. 
     The invention is designed to be ergonomically friendly. The grip bar does not extend beyond the attached weight plates and the apparatus can be manufactured with metal and molded parts, so that all surfaces are smooth and rounded, thereby avoiding injury to the body and preventing snagging of other objects. 
     Although the various features of novelty that characterize the invention have been described in terms of certain preferred embodiments, other embodiments will become apparent to those of ordinary skill in the art, in view of the disclosure herein. Accordingly, the present invention is not intended to be limited by the recitation of the preferred embodiments, but is instead intended to be defined solely by reference to the appended claims.