A pulley device for a belt or chain, method for manufacturing a hollow shaft for such a device and method for assembling such a device

A pulley device 2 for a belt or chain comprises a bearing 20 provided with an external ring 22, and an internal ring 24 with rolling elements 26 mounted in a bearing chamber 28, a pulley 30 secured in rotation with the external ring and with an external surface 32 for engaging with a belt/chain. The device also comprises a hollow shaft 40A, 40B for receiving a screw or bolt for mounting the pulley device. The hollow shaft comprises a bushing 42 and a flange 48 secured to the bushing and which extends radially outwards with respect to a central axis X40 of the hollow shaft, as far as the bearing chamber. The flange is formed with a washer 44 and an endplate 46, while the washer is radially located between the bushing and the endplate. The washer may be metallic and the bushing and/or the end plate may formed from a second or different material such as a synthetic material like polyamide 6-6 and/or a material comprising reinforced fibres. The bushing and/or the endplate may be overmoulded onto the washing.