Releasable thread clamp for a knotting machine

A releasable thread clamping device for a cyclical knotting machine, comprising a hollow knotter mandrel rotatable about its longitudinal axis, a knotter needle of resilient material mounted within said knotter mandrel and supported for axial displacement relative to said knotter mandrel, said knotter needle having a hook at the free front end thereof which engages under tension the inner wall of said knotter mandrel to clamp a thread therebetween, a lifting needle supported for movement parallel to the longitudinal axis thereof and has adjacent its front free end a first inclined surface extending at an acute angle relative to said longitudinal axis thereof, said knotter needle having a second inclined surface axially aligned with said first inclined surface on said lifting needle, and control means for effecting an axial shifting of said lifting needle to effect a movement of said first inclined surface into and out of engagement with said second inclined surface whereby following an engagement of said first and second inclined surfaces a continued movement of said lifting needle will effect an urging of said free end of said knotter needle away from said inner wall to release said thread clamped therebetween.