|
US2205716A
|
Unit heater and air conditioner |
Expired / Lapsed
|
1938-02-04 |
1940-06-25 |
0 |
Details
|
|
US2075487A
|
Effective temperature thermostat |
Expired / Lapsed
|
1935-03-09 |
1937-03-30 |
0 |
Details
|
|
US1921172A
|
Average temperature control mechanism for heating systems |
Expired / Lapsed
|
1932-01-08 |
1933-08-08 |
0 |
Details
|