varies depending on year made, condition, etc. Have seen them 1889 go for 1200.00 and others later dated with cabinets around 500.00 right down to 50.00 so it is really hard to tell unless specifics and then you have to find a collector
The answer to your question is yes he was granted an American patent in 1851 and it was suggested he take out a patent on the treadle (foot plate) also but it was too late to do this as it had been in use too long. In 1885 Singer also patented the Singer Vibrating Shuttle sewing machine.
Patents apply to any machine created under that patent until the patent expires. It does not matter how many times the machine is used or how many times it changes hands, the patent is still a patent.
Charles Weisenthal was the first inventor of the sewing machine, a German, and he was issued a patent for a needle that was designed for a machine, however, the patent did not describe the rest of the machine if one existed.
Greenough did not commercially manufacture his invention and his patent model remains as the only evidence. So his machine is simply called the "Sewing Machine Patent Model."
Sewing machine.
Spooner's patent was for a gravity-fed seeding machine, which turned out not to work.
The first patent (UK) in 1691. Then Jacob Schaffer (Germany) 1767. UK patent To Henry Sidgier for first rotating drum machine in 1782 . The first US Patent in 1797 was awarded to Nathaniel Briggs.
It was called, in quote, "FLYING-MACHINE"
A perpetual motion machine has been deemed impossible by physics; the US patent office allegedly will not consider applications claiming perpetual motion.
The washing machine
Improvement in Bolt Threading Machine, 1870.
John Gorrie patented an ice machine in 1851.