I also have the same clock that was handed down to me from my great great grand parents and mom. did you find anything out about this clock. mine works like new and is tucked away. having same trouble finding info as you. good luck.
I have the same movement but its in a different clock by: Anonymous
I have a Sessions Tambour Humpback clock 1940 NO.277p and the movement in it has the same numbers as yours,Sessions Patent No 1704864
mabey the movement has been changed in mine if your saying they stoped makeing these in 1936,there are pics of the clock i have with all the matching numbers with the exception that they claim theirs to be 1938