It was Hiraga Gennai (1728 - 80), a famous multi-talented naturalist, experimentator, inventor and writer, who first introduced sheep to Japan. He is said to import sheep to get fleece, and had a textile maker the wool woven to sell. But the operation failed. Government sometime tried to grow sheep bussiness but to fail.
In the middle of 19 century, Meiji government imported from U.S. a herd of sheep to make western-style cloth. They began to breed sheep in many places in Japan, including Hokkaido island. They had to invent the westernstyle tools for wool by themselves.
This is called "Kunugi A type", because of its A-shape, and Kunugi wood-made. Many of this type wheel has an iron orifice, but this is made by bamboo or wood.
You can't remove flyer, so you have to reel off the yarn to the other bobbins or a skeiner. There is a hole to hold a skeiner on the backside of the wheel.
This is called "Akasaka-type" wheel. More compact than "Kunugi A type".
The washer is not spring, but coil.
The peddales of both wheels are little bit heavier, but swing rhythmical.
This hand carder is more than 50 years old. The metal plate shows the address of the factory. The needles on the leater are pretty harder.