Patent number question

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Treeservicegirl

New Member
Oct 25, 2021
1
Tidioute PA
Hello, I am new here. I have just gotten my hands on a fisher Baby Bear!! I have a question about the patent number on the door. Mine doesn't have one. It just says
"Pat Pend". Anyone have an idea the year of it? Installed it tonight an omg! I love it!!
 
Pictures can help identify the year the easiest.
If this is a PA stove there will be a stove number and PA written in weld on the bottom.

Other details help to determine where and when it was made such as the angle of the bottom taper on legs, vent pipe weld inside or out, draft cap, handle spring type or ball, handle bends.... A picture with closed door helps the most.
 
Doors were cast at foundries for Bob and Carol Fisher and licensed fabricators had to order the doors from them. Along with the door price was the royalty paid to the Fisher’s, so that’s how they could keep track of what was being made. As doors were ordered, the handle supply changed, handles were bent differently and updated drawings known as revisions were sent to fabricators. As the old stock of doors was used as well as other items attached to them, it becomes difficult to give an exact time of manufacture since an old box of handle springs could be found and used on a later stove. There are instances of older doors not being used for years, and a stove made for themselves of a friend, or for a gift would be used years later. Doors were highly guarded to avoid their sale to someone fabricating a home made stove.

Fabricators were not bound by any contract that forced them to buy items sold by Fisher such as air intake dampers, or door handles, so a few cut costs by making their own parts during certain times which help date stoves from some states. The Fisher’s were concerned about quality control, but not details such as the leg taper as shown on drawings, so some fabricators cut legs square, others made a slight 45* taper, and others tapered the legs as shown on the drawings giving each part a number and dimensions.