Exerciser

An exerciser including a generally horizontal top frame having a front end, a column supporting said top frame, a movable frame mounted on said top frame and movable between said front end of said top frame and said column, said movable frame having two spaced vertical hollow frame sections and a cross frame section interconnecting lowermost ends of said vertical hollow frame sections, two push arms connected pivotally to said movable frame and capable of being pivoted toward each other, and a stop rod extending frontward from said column below said top frame so as to limit movement of said movable frame toward said column, wherein the improvement comprises:

• a first locking unit including a curved positioning plate that extends upward from said cross frame section and that is located between said vertical hollow frame sections of said movable frame, said curved positioning plate curving toward said column and having a guide slit extending from an upper end to a lower end thereof and two aligned grooves which are transverse to said guide slit and which are located adjacent to said lower end of said positioning plate, said first locking unit further including a pivot rod having one end mounted pivotally on said stop rod and two opposed horizontal locating projections extending radially outward therefrom, said locating projections engaging respectively said aligned grooves in said positioning plate when said pivot rod is pivoted and inserted selectively into said guide slit to prevent movement of said movable frame relative to said top frame;
• each of said vertical hollow frame sections having a longitudinal slot formed therein and a notch extending from one side of said longitudinal slot and being spaced from a lowermost end of said slot;
• said movable frame further having two positioning holes which extend through said lowermost end of a corresponding said vertical hollow frame section and said cross frame section;
• each of said push arms having a locking hole which is formed therethrough and which is vertically aligned with a corresponding said positioning hole;
• a second locking unit including two generally L-shaped locking rods, each of said locking rods having a vertical end portion disposed inside a respective one of said vertical hollow frame sections and a horizontal end portion which extends out of said respective one of said vertical hollow frame sections through said slot, said locking rods being movable selectively along said slots between a first position, wherein said horizontal end portions of said locking rods are disposed adjacent to said lowermost ends of said slots and said vertical end portions of said locking rods extend through said positioning holes and into said locking holes in order to prevent pivoting movement of said push arms relative to said movable frame, and a second position, wherein said horizontal end portions engage said notches and said vertical end portions cease to extend into said locking holes to permit pivoting movement of said push arms relative to said movable frame.