Patent ID: 8136300

Claim:
A frame comprising: an upper beam and a lower beam, a seat attached to said lower beam and including a projection extended upwardly from said seat, an anchor attached to said upper beam and including a catch tongue pivotally attached to said anchor with a pivot axle, a spring member engaged with said catch tongue for biasing said catch tongue, a tubular member including a lower portion having an opening for receiving and engaging with said projection of said seat and for detachably anchoring and mounting said lower portion of said tubular member to said seat of said lower beam, said tubular member including a latch shaft attached to an upper portion of said tubular member for selectively engaging with said catch tongue and for pivoting said catch tongue until said latch shaft is moved over said catch tongue, and said spring member biasing said catch tongue to engage with said latch shaft and to latch and lock said latch shaft and said upper portion of said tubular member to said anchor and said upper beam after said latch shaft is moved over said catch tongue, and said tubular member including a chamber formed in said upper portion of said tubular member, a casing engaged in said chamber of said tubular member and secured to said tubular member, a lock device secured to said upper portion of said tubular member and engaged into said casing, and including an actuating shank extended therefrom, a follower slidably attached to said casing and including an actuating end to be moved toward and away from said catch tongue for selectively disengaging said catch tongue from said latch shaft and for allowing said latch shaft and said upper portion of said tubular member to be disengaged from said upper anchor selectively, a rocker arm attached to said actuating shank and rotated in concert with said actuating shank, and including at least one actuating end for engaging with said follower and for moving said actuating end of said follower to engage with said catch tongue and to selectively disengage said catch tongue from said latch shaft, and a key engageable with said lock device for selectively actuating and rotating said actuating shank of said lock device and said rocker arm to engage with said catch tongue and to disengage said catch tongue from said latch shaft.