Constant temperature type crystal oscillator for high stability

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;
• 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, said notch being provided in a peripheral portion of said heat transfer plate in an annular shape, with a plurality of said heating chip resistances being evenly arranged around said notch;
• and wherein
• a heat sink lies between said heat transfer plate and said heating chip resistance and closely contacts with them.

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;
• 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, the heat sink being sheet-shaped having elasticity.