I have the same diagrams of the VB-5 (ВБ-5) as Chris posted. It's basically a modified V-5/V-5M (В-5/В-5М) type fuze, with the lower pyrotechnic self destruct removed and igniferous and not detonative output.
The inner body of the VB-5 now contains a pyrotechnic delay system, which controls initiation of the lower detonator in the slider. The detonator's output initiates the power magazine, which is likely black powder.
The V/W naming is simply down to transliteration standards, especially if the country doesn't use the letter 'V'.
The I-71 (И-71) may be another designation for one of aforementioned the fuzes, or a separate fuze. It's very common for Soviet/Russian aerial fuzes to have an I-xxx code, as well as an index code, and sometimes other designations.
Not sure what the T-5-O (Cyrillic Т-5-О or Т-5-0?) fuze is, though it may suggest a variant of the T-5? However the original T-5 fuze had a larger maximum diameter (≈63 mm and not ≈40 mm) and was much heavier (≈710 g and not ≈265 g), plus its arming system was designed for a high set-back and spin environment.