CharlestonLinda,
Welcome to the QB.
Your machine is what we call a 15 clone. It is a very close copy of the Singer Model 15 made in Japan. Many many millions of them were imported from the late 40s to the 60s by dozens of Japanese companies, and sold under hundreds of names. They are still made today by Indian and Chinese companies.
There is no comprehensive list of who made what and / or when with these machines. Some are marked like the Juki made HOTHER that's my avatar picture.
Others will have a J- A number on them that will tell the manufacturer and yet others will have no markings at all.
Some like Brother made machines will have "BROTHER" prominently cast in the underside of the bed.
They are usually excellent sewing machines a very much capable of most any straight stitch task you'd ask of them.
Joe