Weight lifting apparatus with intermittent drive

Abstract

An adjustable weight lifting apparatus includes a weight lifting device to which a desired amount of weight is attached by attaching a desired number of weight disks and/or auxiliary weights to the weight lifting device. Weight disks are attached to or detached from to the weight lifting device by intermittently advancing pins from or retracting pins into the weight lifting device. Auxiliary weights in differing amounts can be provided to facilitate adjustment of the amount of weight attached to the weight lifting device in smaller amounts than is achieved by attaching or detaching individual weight disks. The weight disks can be prevented from moving radially relative to each other by protrusions and mating recesses on the weight disks. The protrusions can be removably attached to the weight disks.

What is claimed is: 
     
         1 . A weight lifting device, comprising:
 an elongated handle;   a housing, the handle being rotatably attached at an end thereof to the housing, an axially extending opening extending through the housing and the handle;   an axially extending pin disposed in and axially movable relative to the axially extending opening, and   the handle, the housing, and the pin being linked so that rotation of the handle relative to the housing causes intermittent linear motion of the pin.   
     
     
         2 . The weight lifting device according to  claim 1 , comprising a linear Geneva mechanism for converting rotational motion of the handle relative to the housing into intermittent linear motion of the pin. 
     
     
         3 . A weight lifting device, comprising:
 an elongated handle;   a housing, the handle being rotatably attached at an end thereof to the housing, an axially extending opening extending through the housing and the handle;   an axially extending rack disposed in and axially movable relative to the axially extending opening;   a first gear non-rotatably attached to the handle;   a second gear non-rotatably mounted in the housing on an axle perpendicular to a longitudinal axis of the handle and in engagement with and drivable by the first gear; and   a crank non-rotatably mounted on the axle and having at least one peg adapted to intermittently engage the rack upon rotation of the axle.   
     
     
         4 . The weight lifting device as set forth in  claim 3 , wherein the crank and the rack comprise a linear Geneva mechanism for converting rotational motion of the crank into intermittent linear motion of the rack. 
     
     
         5 . The weight lifting device as set forth in  claim 3 , wherein the rack comprises an axially extending rail with a plurality of slots, and the peg on the crank is axially offset from the axle and adapted to intermittently engage the crank by being received in one of the plurality of slots as the crank is rotated to a first rotational position, exit the one of the plurality of slots as the crank is rotated to a second rotational position, and advance the rail while the crank is rotated from the first rotational position to the second rotational position. 
     
     
         6 . The weight lifting device as set forth in  claim 5 , wherein the rail includes, between each pair of the plurality of slots, a radiused recess, and the crank includes a protrusion, the protrusion being received in the radiused recess when the crank is rotated from the second rotational position to the first rotational position. 
     
     
         7 . The weight lifting device as set forth in  claim 6 , wherein the protrusion is a radiused protrusion having a radius matching a radius of the radiused recess. 
     
     
         8 . The weight lifting device as set forth in  claim 3 , wherein the rack comprises first and second axially extending rails, each of the first and second rails comprising a plurality of slots, and wherein the crank comprises
 a first peg axially offset from the axle and adapted to be received in one of the plurality of slots of the first rail as the crank is rotated to a first rotational position, exit the one of the plurality of slots of the first rail as the crank is rotated to a second rotational position, and advance the first rail while the crank is rotated from the first rotational position to the second rotational, and   a second peg axially offset from the axle and adapted to be received in one of the plurality of slots of the second rail as the crank is rotated to a third rotational position, exit the one of the plurality of slots of the second rail as the crank is rotated to a fourth rotational position, and advance the first rail while the crank is rotated from the third rotational position to the fourth rotational position.   
     
     
         9 . The weight lifting device as set forth in  claim 8 , wherein the crank is in the third rotational position while the crank is rotated from the first rotational position to the second rotational position. 
     
     
         10 . The weight lifting device as set forth in  claim 9 , wherein the crank is in the fourth rotational position while the crank is rotated from the second rotational position to the first rotational position. 
     
     
         11 . The weight lifting device as set forth in  claim 8 , wherein the first and second rails each includes, between each pair of the plurality of slots, a radiused recess, and the crank includes
 a first protrusion, the first protrusion being received in one of the radiused recesses in the first rail when the crank is rotated from the second rotational position to the first rotational position, and   a second protrusion, the second protrusion being received in one of the radiused recesses in the second rail when the crank is rotated from the fourth rotational position to the third rotational position.   
     
     
         12 . The weight lifting device as set forth in  claim 8 , wherein central axes of the plurality of slots in the first rail are disposed at a first angle non-perpendicular to a longitudinal axis of the rack, and central axes of the plurality of slots in the second rail are disposed at a second angle non-perpendicular to the longitudinal axis of the rack. 
     
     
         13 . The weight lifting device as set forth in  claim 12 , wherein the first angle and the second angle are equal to each other and disposed on opposite sides of a line perpendicular to the longitudinal axis of the rack. 
     
     
         14 . The weight lifting device as set forth in  claim 8 , wherein the first rail and the second rail are separated by a longitudinal space, and the crank comprises a disk partially disposed in and rotatable in the longitudinal space, the first peg extending from a first surface of the disk, and the second peg extending from a second, opposite surface of the disk. 
     
     
         15 . The weight lifting device as set forth in  claim 14 , wherein the first and second rails each includes, between each pair of the plurality of slots, a radiused recess, and the crank includes
 a first protrusion, the first protrusion being received in one of the radiused recesses in the first rail when the crank is rotated from the second rotational position to the first rotational position, and   a second protrusion, the second protrusion being received in one of the radiused recesses in the second rail when the crank is rotated from the fourth rotational position to the third rotational position.   
     
     
         16 . The weight lifting device as set forth in  claim 3 , comprising
 a second housing, the handle being rotatably attached at a second end thereof to the second housing, an axially extending opening extending through the housing, the handle, and the second housing;   a second axially extending rack disposed in and axially movable relative to the axially extending opening;   a third gear non-rotatably attached to the handle;   a fourth gear non-rotatably mounted in the housing on a second axle perpendicular to a longitudinal axis of the handle and in engagement with and drivable by the third gear;   a second crank non-rotatably mounted on the second axle and having at least one second peg adapted to intermittently engage the second rack upon rotation of the second axle.   
     
     
         17 . The weight lifting device as set forth in  claim 16 , wherein the second crank and the second rack comprise a linear Geneva mechanism for converting rotational motion of the second crank into intermittent linear motion of the second rack. 
     
     
         18 . A weight lifting apparatus, comprising:
 a weight lifting device, comprising
 an elongated handle, 
 a housing, the handle being rotatably attached at an end thereof to the housing, an axially extending opening extending through the housing and the handle, 
 an axially extending pin disposed in and axially movable relative to the axially extending opening, and 
 a linear Geneva mechanism for converting rotational motion of the handle relative to the housing into intermittent linear motion of the pin, the linear Geneva mechanism comprising a crank driven by rotation of the handle, the pin comprising a slider drivable by the crank, and 
   at least one weight disk comprising a hole, the at least one weight disk being attachable to the housing when the pin is received in the hole.   
     
     
         19 . The weight lifting apparatus according to  claim 18 , wherein one 360° rotation of the crank moves the pin one half of a thickness of the weight disk. 
     
     
         20 . The weight lifting apparatus according to  claim 19 , wherein the pin is movable between a fully retracted position in which an axially outer end of the pin is disposed axially inwardly of an axially outer surface of the housing to a fully extended position in which the axially outer end of the pin is disposed axially outwardly of the axially outer surface of the housing.