The Japanese patent website can be found here. After the PAJ link is clicked, people can search for Japanese designs in whatever object interests them. I have been highlighting waterproof construction designs because of an emerging market in the Great Lakes region, and listed links to US and EU designs for waterproof tents in recent posts.
I looked at the Kenyan patent office website, the South African patent office website, and a pan-African body (here). None appeared to put designs online free of charge (I didn't look really thoroughly so may be mistaken), although it might be possible to get them for a fee from the South African website.
What might be helpful for economic development is free public online information for pan-African patents. If countries are concerned that public information combined with weak property rights would be a discouragement to innovation in their countries, then they could restrict the patents to those which are expired or aging (say three years old or more) or those where the patent holder is willing to allow public disclosure (which would admittedly probably be less commercially valuable).
Easy access to African specific patents could allow local innovators to build on knowledge which is specific to African circumstances. Inventions from developed countries may require considerable reengineering to work in African circumstances (for example, waterproof designs for a North European summer may not be robust enough in a tropical storm). There is also a demonstration effect - if a design has been shown to work in an African country, then entrepreneurs may be more willing to risk investment in it than if it had only worked on the other side of the world. Inventors working even with highly generic products in highly similar developed countries often build on local innovation more than foreign innovation, and choose to adapt foreign technology further for local circumstances. A pan-African database would mean that not every entrepreneur has to incur the same possibly elavated costs of adaptation from developed to local contexts.