초록 ▼

The present invention proposes an improved locking structure of a retractable draw bar. The proposed improved locking structure comprises a first joint tube, a second joint tube, a fixed assembly, a movable assembly, two click buttons, and two resilient elements. The movable assembly is inserted in

The present invention proposes an improved locking structure of a retractable draw bar. The proposed improved locking structure comprises a first joint tube, a second joint tube, a fixed assembly, a movable assembly, two click buttons, and two resilient elements. The movable assembly is inserted in the fixed assembly and can steadily move upwards or downwards with respect to the fixed assembly. The upper and lower click buttons and the two resilient elements are axially adjacent and are installed in the fixed assembly to penetrate in the movable assembly. The upper and lower click buttons can work in opposite directions and be secured and positioned in the upper and lower click holes when the draw bar is protracted or retracted. Wedged guide grooves and wedged guide blocks are installed at corresponding positions on the movable assembly and the upper click button, respectively. No matter the movable assembly is pulled upwards or pushed downwards, the upper click button can be pushed sideward and retracted transversely from the click hole. The number of components is reduced and there are higher compatibility and interaction between them. Easy assembly and smooth protraction/retraction and steady positioning of the retractable draw bar can thus be achieved. The present invention can be widely used between any two draw bars. Moreover, the present invention can apply to the upward-pull type or the downward-push type retractable draw bars.

대표청구항 ▼

1. A locking system for a retractable draw bar comprising:a longitudinally extended first joint tube first joint tube having a bottom end portion defined thereon; a second joint tube coaxially receiving in retractable manner at least a portion of said first joint tube, said second joint tube having

1. A locking system for a retractable draw bar comprising:a longitudinally extended first joint tube first joint tube having a bottom end portion defined thereon; a second joint tube coaxially receiving in retractable manner at least a portion of said first joint tube, said second joint tube having opposed first and second tube walls extending longitudinally between top and bottom end portions, said second joint tube having an upper click hole formed through said first tube wall adjacent said top end portion and a lower click hole formed through said second tube wall adjacent said bottom end portion; a fixed assembly fixedly engaging said bottom end portion of said first joint tube, said fixed assembly having an allocation hole extending transversely therethrough; a movable assembly displaceably coupled to said fixed assembly for reversible longitudinal displacement relative thereto, said movable assembly having an inner wall portion formed about a longitudinally extended guide hole, said inner wall portion having a first wedged guide structure formed therein; an upper click button displaceably disposed in said allocation hole of said fixed assembly for transverse displacement between first and second positions relative to said fixed assembly, said upper click button including a main portion and a second wedged guide structure protruding therefrom, said upper click button being biased by a first resilient member toward said first position, said upper click button in said first position passing transversely through said guide hole of said movable assembly to engage said upper click hole of said second joint tube, said second wedged guide structure in said first position retentively engaging said first wedged guide structure of said movable assembly, said upper click button in said second position being disengaged from said upper click hole of said second joint tube; a lower click button disposed in said allocation hole of said fixed assembly in substantial transverse alignment with said upper click button for transverse displacement relative to said fixed assembly between extended and retracted positions, said lower click button being biased by a second resilient member toward said extended position, said lower click button in said extended position engaging said lower click hole of said second joint tube, said lower click button in said retracted position being disengaged from said lower click hole of said second joint tube; whereby said movable assembly is displaceable responsive to user manipulation thereof to disengage said second wedged guide structure from said first wedged guide structure to thereby displace said upper click button from said first position to said second position, said first joint tube being released thereby for longitudinal adjustment relative to said second joint tube.