Patent ID: 7479835
Filing Date: 2009-01-20
Classification: H03B,H05K

Abstract:
1. A constant temperature type crystal oscillator which comprises: a crystal oscillator that is provided upright on a circuit board, and which comprises a plurality of lead wires extending out from a bottom face of an oscillator container in which a crystal piece is hermetically sealed; an oscillation element arranged on said circuit board and configuring an oscillation circuit in conjunction with said crystal oscillator; and a temperature control element including at least a heating chip resistance and a thermistor, arranged on said circuit board, and configuring a temperature control circuit that keeps an operating temperature of said crystal oscillator constant, the circuit board having at least a single layer of cuts defined in regions thereof surrounding at least a region in which the heating chip resistance and thermistor are arranged; and which is provided with a heat transfer plate between said heating chip resistance and a bottom face of said oscillator container, wherein, said heat transfer plate has a notch into which said heating chip resistance is fitted, and a heat sink lies between said heat transfer plate and said heating chip resistance and closely contacts with them.