Patent attributes
An improved device for athletic exercise by pulling at a resisting force. The device consists of a number of spring housing assemblies that are stacked and clamped in a column with at least one pulley wheel assembly to which a cord and pull handle is attached. A grooved metal shaft is disposed throughout the column longitudinal axis to drive all the constant-force spring assemblies which are stacked inside the device when the pulley wheel is caused to rotate. A person uses the device by first selecting which spring assemblies he wants to produce a particular resisting force level, by pushing separate selector levers, one for each spring. He then pulls at the pull handle to experience the chosen resisting force. The device design allows a user the choice of many resisting force levels, using only a small number of spring assemblies. The device is small, light in weight and conveniently shaped for easy attachment to any suitable restraining object.