recesses 32 of the adjustable ring 19 are brought into register with the outer pins 36 spring 15 will thereby displace the cylindrical pin 33 to the left in fig1 until pin 35 engages the left wall surface of the hole 17 naturally at the same time the outer pins 36 have been pressed into the recesses 32 of the adjustable ring 19 and it is understood that hereby the adjustable ring is catched in the actual angular position the adjustable ring is in other words pre tensioned since the springs 30 tend to bring said adjustable ring back to the initial position thereof by this manual step the connecting device has been brought to a ready for action position when the ejector device is made operative so that the connecting device is brought into engagement with the ejector pin 1 of the tool the ejector pin will enter the bore 13 as may be seen in fig1 the ejector pin 1 has a number of ridges 37 of the same profile as the grooves in 22 in the jaws the jaws 21 are within the limits defined by the recesses 25 and the pins 26 freely movable in the guidings thereof therefore the jaws will be displaced in a direction.