Automatically retractable chalk line device

摘要: In accordance with the present invention an automatically retractable chalk line device is provided having a housing in which power spring drives first large diameter gear through shaft. The driving engagement smaller located below spring. second partially above retaining spool, holds line. relative diameters of two gears as compared small provides mechanical advantage. A disc brake mounted for braking one gears, preferably gear. An arrangement engaging and disengaging provided. This includes cam surface slotted plate resiliently biased into engaged position by surface. release button actuated to move between retraction opening movable open closed allow introducing assembly adjacent exit portion where exits anchor at end strong advantage achieved from dual enable longer up hundred feet or more be utilized. acting on very effective system. deactivation system readily accessible convenient operate. Chalk inserted sliding loading unloading chalk.