Patent ID: 8505418
Filing Date: 2013-08-13
Classification: B25B

Abstract:
1. A tool extension comprising: a housing including a longitudinal bore formed therein and having a non-circular cross section, and said housing including a first end portion and a second end portion, and including a peripheral slot formed in an intermediate portion of said housing, and said housing including an opening formed therein and located close to said first end portion of said housing, a positioning ring engaged with said peripheral slot of said housing and extended radially and outwardly from said housing, a detent slidably received and engaged in said opening of said housing and partially extendible into said longitudinal bore of said housing, a fetching device including a shank having a non-circular projection extended therefrom for engaging with said bore at said second end portion of said housing and for allowing said shank to be rotated by said housing, and said shank including a non-circular engaging hole formed therein for engaging with a tool element and for allowing said tool element to be selectively rotated and driven by said shank and said housing, a shaft slidably received and engaged in said bore of said housing, and including a non-circular cross section for engaging with said non-circular bore of said housing and for guiding said shaft to slide axially relative to said housing only, and for preventing said shaft from being rotated relative to said housing, and for allowing said shaft to be rotated by said housing, said shaft including a stem extended therefrom for coupling to a driving tool, and said shaft including a first outer peripheral groove and at least one second outer peripheral groove formed therein for selectively engaging with said detent and for adjustably positioning said shaft to said housing at selected positions, and a control device attached to said housing for selectively engaging with said detent and for actuating said detent to selectively engage with said shaft and to lock said shaft to said housing at the selected positions, said control device including a sleeve having a chamber formed therein for receiving and engaging with said housing, said sleeve including a peripheral flange extended radially and inwardly from a first end portion of said sleeve, and a first spring biasing member engaged onto said housing and received in said chamber of said sleeve and engaged between said peripheral flange of said sleeve and said positioning ring for biasing and forcing said sleeve to move away from said positioning ring and said detent and to move toward said second end portion of said housing, a control ferrule having a compartment formed therein for receiving and engaging with said housing, said control ferrule being secured to said sleeve and moved in concert with said sleeve, said control ferrule including an inner peripheral flange rib extended radially and inwardly into said compartment of said control ferrule, a second spring biasing member engaged onto said housing and received in said compartment of said control ferrule and engaged between said inner peripheral rib of said control ferrule and said positioning ring for biasing and forcing said control ferrule to move away from said positioning ring and said second end portion of said housing and to move toward said first end portion of said housing, said control ferrule including a first trough and a second trough formed therein and spaced from each other for selectively receiving and engaging with said detent and for defining an inner peripheral actuator between said troughs of said control ferrule, said actuator being selectively engageable with said detent for actuating said detent to selectively engage with either of said first or said at least one second peripheral grooves of said shaft and to lock said shaft to said housing at the selected positions, said actuator being biased and forced to engage with said detent by said first and said second spring biasing members when said sleeve and said control ferrule are released, and said detent being selectively received and engaged in said first trough of said control ferrule and disengaged and separated from said actuator of said control ferrule and disengaged and separated from said shaft when said sleeve and said control ferrule of said control device are moved away from said first end portion of said housing, for allowing said shaft to be moved and adjusted relative to said housing to the selected positions, and said actuator of said control ferrule being biased and forced to engage with said detent again and to force said detent to engage with either of said first or said at least one second peripheral grooves of said shaft when said sleeve and said control ferrule of said control device are released, and said detent being selectively received and engaged in said second trough of said control ferrule and disengaged and separated from said actuator of said control ferrule and disengaged and separated from said shaft when said sleeve and said control ferrule of said control device are moved away from said second end portion of said housing, for allowing said shaft to be moved and adjusted relative to said housing to the selected positions, and said actuator of said control ferrule being biased and forced to engage with said detent again and to force said detent to engage with either of said first or said at least one second peripheral grooves of said shaft when said sleeve and said control ferrule of said control device are released.