Swinging rack structure for sit-up machines

Abstract

A swinging rack structure for sit-up machines includes a pair of lower bar brackets and an upper bar bracket. The upper bar bracket has one end fastening to an axle to pivotally couple with the lower bar brackets in the axial direction or normal to the axial direction and another end releasably anchoring on the lower bar brackets. When an user wants to get up, the upper bar bracket may be released on one side and turned about the axle to form an open condition so that the user may get up conveniently without interference.

What is claimed is:  
     
         1 . A swinging rack structure for a sit-up machine mounted onto a sit-up machine frame which equips with a supporting board for an user to grasp, the swinging rack structure comprising: 
 a pair of lower bar brackets having respectively one end pivotally engaging with two sides of the frame; and    an upper bar bracket having one end pivotally coupling with the end of the lower bar brackets through an axle and another end releasably engaging with the another end of the lower bar brackets through a latch apparatus such that when the latch apparatus is released the upper bar bracket is turnable about the axle to form an opening on one side.    
     
     
         2 . The swinging rack structure for a sit-up machine of  claim 1 , wherein the frame includes a front rack, a rear rack, a support bar, a seat board, a backrest board, a driving rack and a retaining rack, the seat board being fixedly mounted onto the frame, the backrest board being pivotally engaging with the frame and movable relative to the seat board such that the backrest board is turnable when the user does sit-up exercise.  
     
     
         3 . The swinging rack structure for a sit-up machine of  claim 1 , wherein the upper bar bracket further includes a connecting section to couple with the lower bar brackets.  
     
     
         4 . The swinging rack structure for a sit-up machine of  claim 3 , wherein the axle is extended from the connecting section.  
     
     
         5 . The swinging rack structure for a sit-up machine of  claim 1 , wherein one of the lower bar brackets has one end coupling with an anchor dock to pivotally engage with the axle.  
     
     
         6 . The swinging rack structure for a sit-up machine of  claim 1 , wherein the latch apparatus is an inserting pin.  
     
     
         7 . The swinging rack structure for a sit-up machine of  claim 1 , wherein the axle is pivotally engaged with the lower bar bracket on the central axis thereof in a radial direction.  
     
     
         8 . The swinging rack structure for a sit-up machine of  claim 1 , wherein one of the lower bar brackets has an anchor seat fastening to the top end thereof to couple with the upper bar bracket through another axle, the anchor seat having an anchor trough and a slot.  
     
     
         9 . The swinging rack structure for a sit-up machine of  claim 8 , wherein the upper bar bracket has an anchor member located on one end slidable in the anchor trough.  
     
     
         10 . The swinging rack structure for a sit-up machine of  claim 8 , wherein the another axle runs through the slot of the anchor seat and is pivotally engaged with the lower bar bracket on the central axis in a normal direction.