The fifth seed Indo-Brazilian partner came back from behind for a 4-6 6-1 6-4 victory in the second and final round of the Qualifiers.
Now at least five Indians, with different partners, are set to compete in the doubles event of the grass court Grand Slam. Leander Paes, Mahesh Bhupathi, Rohan Bopanna and Divij Sharan are the other Indians who have got direct entry.
Last year, Purav had played at the Wimbledon with Sharan. This year, left-handed Sharan has got a direct entry with Taipei's Yen Hsun-Lu.
However, they came back strong and saved a break point while serving for the match. Demoliner smashed winner to seal their spot in the main draw.
They had edges past India's Somdev and Russia's Evgeny Donskoy 7-5 7-5 in the first round after being down 2-5 in the opening set.