Leg press and abdominal crunch exercise machine
View Patent ↗An exercise machine composed of a frame, a first four bar linkage system, a second four bar linkage system, and a means for transferring an incident force from the legs of a user is disclosed. The first four bar linkage system is operably mounted on the frame and operably connects the transferring means to the frame to allow for back and forth movement of the transferring means along a path of travel about an instantaneously changing axis of rotation. The second four bar linkage system operably engages the first four bar linkage system. Either or both of the first four bar linkage system and the second four bar linkage system are operably connected to a resistance means, whereby the second four bar linkage system operates in conjunction with the first four bar linkage system and the resistance means to create a mechanical disadvantage to the user.
1. A force conditioning device comprising:
a first four bar linkage system including a first top bar and at least one rear bar;
a second four bar linkage system operably connected to the first four bar linkage system, the second four bar linkage system including a second top bar positioned underneath the first top bar;
the first and second four bar linkage systems operating to provide a mechanical advantage to a resistance means acting on the device in opposition to a force acting on the device, at least three bars of each of the first and second four bar linkage systems pivotally connected in a direct pivotal relationship to at least one other bar of the first and second four bar linkage systems;
the second top bar including a flexible member connection portion extending beyond the at least one rear bar in a direction generally away from the other bars of the first four bar linkage; and
a flexible member directly associating the resistance means with the flexible member connection portion of the second top bar.
2. The device of claim 1 , wherein a portion of the first four bar linkage system comprises a portion of the second four bar linkage system.
3. The exercise device of claim 1 , wherein the flexible member comprises a cable.
4. The exercise device of claim 1 , wherein the resistance means comprises a weight stack.
5. The device of claim 1 , wherein each bar of each of the first and second four bar linkage systems is pivotally connected in a direct pivotal relationship to at least one other bar of the first and second four bar linkage systems.
6. An exercise machine comprising:
a frame;
a means for transferring an incident force from the legs of a user;
a first four bar linkage system operably mounted to the frame and operably connecting the transferring means to the frame, the first four bar linkage system for allowing back and forth movement of the transferring means along a path of travel about an instantaneously changing axis of rotation and for changing the angle of inclination of the transferring means to maintain the transferring means in a position normal to the length of the lower legs of the user during a corresponding leg extension movement of the user;
a second four bar linkage system operably engaging the first four bar linkage system, at least three bars of each of the first and second four bar linkage systems pivotally connected in a direct pivotal relationship to at least one other bar of the first and second four bar linkage systems;
the first four bar linkage system including a first top bar and at least one rear bar;
the second four bar linkage system including a second top bar positioned underneath the first top bar;
the second top bar including a flexible member connection portion extending beyond the at least one rear bar in a direction generally away from the other bars of the first four bar linkage;
a resistance means; and
a means for directly connecting the flexible member connection portion of the second top bar to the resistance means, the means for operatively connecting comprising a flexible member; wherein
the second four bar linkage system operates in conjunction with the first four bar linkage system and the resistance means to create a mechanical disadvantage to the user.
7. The exercise machine of claim 6 , wherein the mechanical disadvantage comprises a continual increase in the incident force required of the user to exert on the transferring means during the leg extension movement to counteract a constant force exerted by the resistance means.
8. The exercise machine of claim 7 , wherein the constant force exerted by the resistance means is translated through the second four bar linkage system and the first four bar linkage system as an opposing force substantially normal to the transferring means and substantially opposite the incident force.
9. The exercise machine of claim 6 , wherein the second four bar linkage system is further operably engaged with at least one of the transferring means and the frame.
10. The exercise machine of claim 6 , wherein a portion of the first four bar linkage system comprises a portion of the second four bar linkage system.
11. The exercise machine of claim 6 , wherein a portion of the first four bar linkage system comprises a portion of the transferring means.
12. The exercise machine of claim 6 , wherein a portion of the first four bar linkage system comprises a portion of the frame.
13. The exercise machine of claim 6 , wherein the resistance means comprises a weight stack.
14. The exercise machine of claim 6 , wherein the means for operably connecting further comprises the flexible member threaded through a pulley system, and wherein at least a portion of the pulley system is operably mounted on the frame.
15. The exercise machine of claim 14 , wherein a portion of the pulley system is operably mounted to the flexible member connection portion of the second top bar.
16. The exercise machine of claim 14 , wherein the flexible member comprises a cable.
17. The exercise machine of claim 6 , wherein each bar of each of the first and second four bar linkage systems is pivotally connected in a direct pivotal relationship to at least one other bar of the first and second four bar linkage systems.