the working pressure of conduit system 21 is increased the thread tension in the entire creel is raised by altering the working pressure by assistance of regulator 23 the thread tension can be adjusted as desired the braking pressure may for example lie in the range of eight bar so that the braking shoe 17 remains in contact with the appropriate braking surface and thus a rapid braking of the spools on the creel can occur switching valve system 30 has connecting sections 31 and 33 and blocking chamber 32 which does not permit passage of fluid when the adjacent machine is operating a signal is sent via input means 41 to make section 31 operative and connect pressure means 18 to conduit system 21 when the said machine is shut off a signal is sent via input means 42 to make section 33 operative and connect pressure means 19 to conduit system 21 thus driving the major braking system of shoe 17 to the internal braking surface of drum 4 there is also a plurality of further possibilities the tensioning lever 8 can be biased by an additional weight not shown this weight can be changed the weight can also be attached to another lever arm not shown angularly displaced relative to the tensioning lever the alternate embodiment of fig3 and 4 corresponds substantially to that illustrated in fig1 and 2 identical parts have the same reference numbers throughout the figures fig5 is a detailed schematic view of the magnetic system of fig3 and 4 an important difference in this alternate embodiment is the replacement of the friction brake braking band 5 of fig1 and 2 with an.