Rotary driven linear actuator

Actuator apparatus for a linearly translating tool, said apparatus comprising:

• a drive shaft adapted to be driven via drive means which is rotatable in a single direction only;
• reciprocating means for actuating said tool;
• means for coupling said reciprocating means to said drive shaft such that when said drive shaft is rotated in said direction said reciprocating means moves linearly to operate said tool;
• and
• means for uncoupling said reciprocating means from said drive shaft upon completion of an operating stroke associated with said tool, said uncoupling means including structure for user adjustment in order to selectively vary said operating stroke,
• said coupling means includes a helical groove formed on said drive shaft and at least one projecting element associated with said reciprocating means which engages said helical groove such that when said drive shaft is rotated said reciprocating means translates linearly along its axis,
• said at lease one projecting element comprises a ball bearing.

Actuator apparatus for a linearly translating tool, said apparatus comprising:

• a drive shaft adapted to be driven via drive means which is rotatable in a single direction only;
• reciprocating means for actuating said tool;
• means for coupling said reciprocating means to said drive shaft such that when said drive shaft is rotated in said direction, said reciprocating means moves linearly to operate said tool;
• and
• means for uncoupling said reciprocating means from said drive shaft upon completion of an operating stroke associated with said tool, said uncoupling means including structure for user adjustment in order to selectively vary said operating stroke,
• said coupling means includes a helical groove formed on said drive shaft and at least one projecting element associated with said reciprocating means which engages said helical groove such that when said drive shaft is rotated, said reciprocating means translates linearly along its axis,
• said coupling means includes one or more apertures in said reciprocating means and means for maintaining the or each projecting element in contact with a respective aperture and with said helical groove.