Design and development of a table mounted manual seed cracking machine for a hard seed (Deocla Reflexa Hook F)

Abstract

Dioclea reflexa seed is a non-conventional seed widely used in the south-eastern Nigeria for culinary and herbal purposes. In using it for these purposes, cracking of the seed to expose the cotyledon is a necessity. However, the seed is seen as one of the hard seeds difficult to crack manually. This work hereby presents the conceptual solution and the fabricated prototype of the manually operated machine to efficiently and safely crack the seed. The design concept involved pushing the seed into a converging passageway with the attendant reaction of the narrowing space-seed interface developing a force that will eventually crack the seed. The machine developed, which also serves as a proof of the concept was fabricated from mild steel using established methods of metal fabrication. The machine prototype was evaluated for seed cracking efficiency as well as the perceived ease of use by operators. Results shows that the machine achieved 96% cracking efficiency and the average response of the test subjects invited to operate the machine was that it is easy to operate.