Extensible bar with a simplified locking system

The invention refers to an extensible bar for tractors, comprised by a bar 1 and a sleeve 2 that slide over one another and are kept together by a pin 9 and including a locking system 3 . The locking system is comprised by a latch 7 that prevents sliding movement between the sleeve 2 and the bar 1 when it is positioned within the housings of the bar and sleeve when they are aligned, by means of the actuation of a wire spring 6 . The assembly is unlocked when the latch 7 is manually pulled out of the housings by means of a pull handle 8 directly attached to the latch. The locking system can be blocked to facilitate the detachment of the accessory, by turning the latch 7 about the wire spring 6 , to prevent the latch 7 from engaging the housing. All these three functions: locking, unlocking and blocking of the system are performed by an assembly of only three parts 6, 7 and 8 of low production cost.