04504733 is referenced by 14 patents and cites 11 patents.

An electrically-heated dry bath wherein a metal block having receptacles for receiving test tubes or the like has resistor heaters fixed thereto and a thermistor temperature sensor therein. A control circuit is provided which connects and disconnects electrical current to and from said heaters in response to the temperature sensor. The control current is fedback such as to eliminate a factor J(S) from the overall transfer function of the circuit, J(S) being a transfer function expressing how various thermal time constants in the bath would, unless neutralized, make the effective time constant of the controlled system deviate from the ideal on-off transfer function.

Title
Dry bath temperature control
Application Number
6/610447
Publication Number
4504733
Application Date
May 15, 1984
Publication Date
March 12, 1985
Inventor
William J Walsh
Dubuque
IA, US
Agent
Joseph C MacKenzie
Robert A Gerlach
Assignee
Sybron Corporation
NY, US
IPC
H05B 3/06
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