Production of composite insulators by injecting different screens onto an insulator shank

The invention relates to the production of composite insulators consisting of a shank in the form of a bar or a tube, which is provided with a covering and which comprises plate-like screens which are distanced from each other. The covering and the screens are made of an elastomer material with high insulating qualities. As a result, the number, distance, form and size of the screens can vary from insulator to insulator. According to the invention, at least one injection mould ( 10 a , 10 b, 11 a , 11 b , 12 a , 12 b , 13 a , 13 b ) for injecting a screen ( 2, 3, 4, 5, 19, 20, 21, 22 ) is arranged downstream from a device which is used to provide the shank ( 1 ) with a covering. The injection mould can be advanced in order to inject a screen upon the shank and opened in order to unmould said screen. An advancing device is also provided in order to displace ( 16 ) the shank ( 1 ) or the screen mould. Each time the shank ( 1 ) or the screen mould is displaced, the position of the latter with respect to the shank enables a subsequent screen to be injected.