Nissin Motor Co., Ltd., Nagoya City, 1927-53
In fact, Nissin is still in business today under the name Axess (see this link), but the period of interest to me is just the pre-WWII and immediate post WWII time frame. Per the Axess web site, Nissin started production of utility vehicles in 1927. Per the two advertisements, early models used 600cc and later offered 675cc 4 stroke engines. While the later versions may have used their own engine designs, the early advertisement seems to indicate it uses a JAC engine. They had chain, rather than shaft drive to the rear wheels and appear to have been sold as simply Nissin (ニッシン号).
Post WWII, they produced a model called the Happy Seven (ハッピーセブン号). I have yet to find a decent photo of one, but they were produced between 1951 and 1953. Nissin used a 250cc OHV 4 stroke single cylinder engine made by Mizuho Automobile and interestingly enough, they obviously have a long history with each other as Axess was formed from the coming together in 2014 of Nissin Motor Co., Ltd., Mizuho Automobile Kogyo Co., Ltd., and a third company called Takara Parts Co., Ltd..
This is the only photo supposedly showing a Happy Seven that I've been able to find, and it doesn't show it well at all. The caption lists the bikes from left as being the Happy Seven 250cc, a Meguro 350cc, and then two Monarch M3 250cc machines. The photo was taken in 1955 and appeared in a magazine which is no longer in print called The Motor Cyclist in 1998.