JPH01248807A - Crystal oscillator - Google Patents

Abstract

PURPOSE:To obtain the oscillation output with high stability and high purity with a small quantity of energy consumption by storing the crystal oscillator and filter of an oscillating circuit into a constant temperature bath having respective heating mechanisms, them thermally and controlling respective heating mechanisms in parallel by the detecting output of a temperature detecting element provided in the middle. CONSTITUTION:A crystal oscillator 1 of an oscillating circuit is housed into a first constant temperature bath 2, and a first heating mechanism 3 is provided. A crystal oscillator 4 of a filter is housed into a second constant temperature bath 5 and a second heating mechanism 6 is provided. Constant temperature baths 2 and 5 are mutually thermally combined and a temperature sensor 7 is provided approximately in the middle. The detecting output of a temperature sensor 7 is inputted to a temperature control circuit 8 and respective heating mechanisms 3 and 6 are controlled in parallel by the output. The constant temperature baths 2 and 5 are held at a substrate 9 and an oscillating circuit, a filter, the heating mechanisms 3 and 6 and the temperature control circuit 8 are assembled at the substrate 9. Since the constant temperature baths 2 and 5 are thermally combined, the mechanisms 3 and 6 provided respectively can be controlled in parallel with the temperature control circuit 8 by the detecting output of a single temperature sensor 7 and the energy consumption is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention relates to a crystal oscillator that uses a crystal resonator to obtain highly stable and highly pure signals.

(Technical background of the invention and its problems) Conventionally, oscillators that can obtain highly stable and high-purity signals have been stabilized by storing the crystal resonator of the oscillation circuit in a thermostatic oven, and then transmitting the oscillation output to the crystal resonator. There is a known device that outputs the signal through a narrowband filter using the .

In this way, as shown in the spectrum of the oscillation output shown in FIG. 3, the phase noise existing near the oscillation output 11,
Noise components 12 such as amplitude noise can be removed.

However, even if only the oscillation output is stabilized, the passband of the filter also changes depending on the temperature, so in extreme cases, the oscillation output may deviate from the passband of the filter.

For this reason, it is conceivable to use a filter with a wide band so that the oscillation output is always within the pass band even if the pass band changes, but in this case, the ability to remove noise components will be low.

Therefore, in order to improve the noise removal ability and maintain the oscillation output within the passband of the filter even when the temperature changes, the filter must also be housed in a constant temperature oven so that it is not affected by temperature changes.

However, if the crystal resonator of the oscillation circuit and the filter are each housed in a thermostatic oven, the volume increases, and the temperature of the two thermostatic ovens must be controlled, resulting in an increase in power consumption.

(Object of the Invention) The present invention has been made in view of the above circumstances, and allows the crystal resonator and filter of the oscillation circuit to be placed in an environment where they are not affected by temperature changes, with minimum volume and power consumption. The object of the present invention is to provide a crystal excavator that can thereby obtain a highly stable and highly pure oscillation output.

(Summary of the Invention) The present invention provides a method for detecting temperature detection by storing a crystal oscillator of an oscillation circuit and a filter in a thermostat having separate heating mechanisms, and thermally coupling the crystal oscillator and filter of an oscillation circuit to each other, and detecting the temperature by a temperature detection element disposed between the two. The heating mechanism is characterized in that each heating mechanism is controlled in parallel depending on the output.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing one embodiment of the present invention.
is a crystal resonator of an oscillation circuit, which is housed in a first constant temperature bath 2 and provided with a first heating mechanism 3.

4 is a crystal oscillator of the filter, and a second thermostat 5
A second heating mechanism 6 is provided.

The eleventh second constant temperature baths 2.5 are thermally coupled to each other, and a temperature sensor 7 is disposed approximately in the middle thereof. Then, the detection output of the temperature sensor 7 is manually sent to the temperature control circuit 8, and the first and second heating mechanisms 3.6 are controlled in parallel with this output.

FIG. 2 is a perspective view showing a specific example of the mechanism shown in FIG.
For example, the first thermostatic chamber 2 is machined from an aluminum block.
A crystal resonator of an oscillation circuit is housed in the hollow part of the oscillator, and the first heating mechanism 3, for example, a heating wire is wound around the crystal resonator of the oscillation circuit.

The second constant temperature bath 5 is made of, for example, press-molded metal thin plate, houses a filter crystal resonator therein, and has a second constant temperature chamber 5 on the outer periphery.
The heating mechanism 6, for example, has a heating wire wound around it.

The first and second constant temperature chambers 2.5 are fixed together by soldering or the like, mechanically and thermally connected, and a temperature detecting element 7, for example a -Cf thermistor, is installed in the middle. .

Then, the first and second thermostatic chambers 2.5 are held on the substrate 9,
On this substrate 9, an oscillation circuit having the crystal resonator 1 as a frequency determining element, a filter utilizing the resonance of the crystal resonator 4, and a detection output of the temperature detection element 7 are used to generate first and second heating mechanisms 3.6. by controlling the first and second constant temperature baths2.
A temperature control circuit 8 is included to control the temperature of the temperature control circuit 5 to a predetermined temperature.

Then, the substrate 9 is held by a metal base 10, and an oscillation output is derived and power is supplied through the terminal 11 implanted in the base 10. Furthermore, the base 10
A cover (not shown) is placed over the top to provide electrical shielding and mechanical protection.

With such a configuration, the first and second thermostats 2.5 are thermally coupled, so the heating mechanism 3 provided in each
．． 6 can be controlled in parallel by the temperature control circuit 8 using the detection output of a single temperature sensor 7, and the mechanism is simple and power consumption can be reduced.

Note that the present invention is not limited to the above embodiments,
For example, the interior of a single constant temperature oven may be divided into two compartments for electrical shielding, and each compartment may house an oscillation circuit and a crystal resonator of a filter.

(Effects of the Invention) As described in detail above, according to the present invention, it is possible to provide a crystal excavator which has a simple structure, has a small increase in power consumption, and can obtain highly stable and highly pure oscillation output.

[Brief explanation of the drawing]

1M is a block diagram showing one embodiment of the present invention, FIG. 2 is a perspective view of the above embodiment, and FIG. 3 is a diagram showing the spectrum of oscillation output. 1.4... Crystal camera 2.5... Constant temperature chamber 3.6... Heating mechanism 7... Temperature detection element 8...・Temperature control circuit 9...Board diagram 1

Claims (2)

[Claims] (1) First and second constant temperature chambers each housing a crystal resonator of an oscillation circuit and a crystal resonator of a filter for filtering the oscillation output of this oscillation circuit, and are mutually electrically shielded and thermally coupled; , first and second heating mechanisms provided in the first and second thermostatic ovens, a temperature detection element provided between the first and second thermostatic ovens, and a detection output of the temperature detection element. A crystal oscillation circuit comprising: a temperature control circuit that controls the heating mechanism; and a temperature control circuit that controls the heating mechanism. (2) A crystal oscillator according to claim 1, wherein the first and second thermostatic chambers are electrically shielded inside a single container and thermally coupled.