Abstract: In an apparatus for joining textile threads with the aid of compressed air, there is provided a device for checking the tearing strength of the joint zone of the threads before their extraction from the apparatus. The device comprises at least one mobile member arranged to act on the loop formed by the joined threads with a predetermined traction force at an intermediate point between the points at which the threads are locked at the apparatus inlet. Control means are provided which are operated so that they travel through a predetermined outward and return stroke and act on said mobile member by way of a yieldable coupling which is set to yield when the predetermined traction force is exceeded.

Abstract: An apparatus for joining textile threads with the aid of compressed air, for mounting in an automatic winding machine, comprises, in front of and behind a mixing chamber, opposing walls with guides for positioning the threads laterally to the chamber and perpendicularly to its longitudinal axis. The front wall carries members for crossing-over the threads before their insertion into the chamber. In the vicinity of the positioning guides for the thread locking members, the opposing wall, at which the threads to be joined enter the apparatus, carries adjustable members for adjusting the length of the free ends of the threads after they have been cut, and an adjustable member for operating a valve which controls the entry of compressed air into the chamber. A control drum which can be coupled to a power take-off of the winding machine is provided with profiled cam grooves for controlling the movements of the mobile members of the apparatus.