JPS59153317A - Crystal oscillator with temperature compensation - Google Patents

Abstract

PURPOSE:To obtain a crystal oscillator with small size, large temperature gain and very slight change in oscillating frequency even when ambient temperature is changed by making the temperature change of the crystal oscillator very small against the change in the ambient temperature. CONSTITUTION:The 1st positive characteristic porcelain 2 is fitted to a metallic case outer wall of a crystal oscillator 1 in the way of heat conduction, the 2nd positive characteristic porcelain 5 is fitted to the bottom 4 of a metallic case 3 containing the crystal oscillator 1 and the 1st positive characteristic porcelain 2 in the way of heat conduction, and the positive characteristic porcelains 3 and 5 are connected electrically in series via the metallic case of the crystal oscillator 1 with a jumper 6. Further, a space is provided so that the crystal oscillator 1 does not directly contact with the positive characteristic porcelains 2,5. Then, the temperature change of the crystal oscillator 1 is made very small against the ambient temperature change. Thus, the change in the oscillating frequency is very slight even when the ambient temperature is changed and the crystal oscillator having small size and large temperature gain is obtained.

Description

[Detailed Description of the Invention] The present invention minimizes the change in the height of the crystal resonator in response to changes in ambient humidity, so that even if the ambient temperature changes, the vibration frequency changes only slightly. Small and
This invention relates to an inexpensive crystal resonator with a large temperature gain.

(Prior art) Around the crystal oscillator? A humidity-compensated crystal resonator is known in which a crystal resonator is combined with a positive characteristic porcelain heating element having a self-temperature compensation function for the purpose of reducing changes in vibration frequency with respect to changes in M degrees.

Conventionally known temperature-compensated crystal resonators have a structure in which a positive characteristic porcelain is heat-conductively attached to the outer wall of a quartz crystal resonator container housing a quartz plate, and the whole is simply housed in another porcelain, or a quartz crystal resonator is used. A structure in which a positive characteristic porcelain is attached to a container that houses the resonator for thermal conductivity, and a crystal resonator is simply housed in this container, and a structure in which a normal metal wire heating element is wrapped around the crystal resonator, and a positive characteristic porcelain is For example, when the ambient humidity changes from -80°C to +60°C, the temperature of the crystal oscillator changes from 80°C to +60°C. Even if the temperature is adjusted strictly to 40°C, the temperature will change over a range of 10°C or more.
The 7-crystallinity change of a quartz crystal pendulum (1'llil) is usually 2
~3. Even if strictly adjusted, it is only 7~8.5, so the vibration frequency of the crystal resonator would change greatly.

Furthermore, a crystal lifter is also known in which a normal heating element is combined with an electronic temperature control mechanism for the purpose of reducing changes in the imaging frequency due to the ambient temperature of the crystal resonator. Although such a crystal resonator can have a very large temperature gain, it is large and expensive, so it can only be used for certain limited applications.

For this reason, there has been a strong desire for a crystal resonator that has a large temperature gain, is small, and is inexpensive.

(Structure of the Invention) The present invention has a large temperature gain that meets these requirements.
It is a small and inexpensive crystal oscillator, and it is the first crystal oscillator.
A positive characteristic porcelain is thermally attached, a second positive characteristic porcelain is thermally attached to a container for storing the positive characteristic porcelain, and the first positive characteristic porcelain and the second positive characteristic porcelain are connected in a 'ML' manner. The quartz crystal resonator, the first positive characteristic porcelain, and the second positive characteristic porcelain are connected externally and are a temperature compensated quartz crystal sensor configured so as not to be in direct contact with each other.

The structure of the present invention will be explained in detail with reference to FIG. 1, which is a schematic cross-sectional view of a specific example thereof. A first positive characteristic porcelain 2 is thermally attached to the outer wall of a metal case of a crystal resonator 1, and a crystal A metal container 8 that houses the vibrator 1 and the first positive characteristic porcelain 2
A second positive characteristic porcelain 5 is attached to the bottom 4 of the porcelain 5 for thermal conduction,
The first positive characteristic porcelain 2 and the second positive characteristic porcelain 5 are electrically connected in series by a connecting wire 6 via the metal case of the crystal resonator. Also, a crystal oscillator 1 and a first positive characteristic porcelain 2
A space is provided so that they do not come into direct contact with the second positive characteristic porcelain 5. The terminals 7, 7' of the crystal oscillator 1 are taken out from the bottom 4 of the container 8 while being electrically insulated from the container, one terminal 8 of the custom-made porcelain 2, 5 is connected to the bottom s4 of the metal case, and the other terminal 8 is connected to the bottom s4 of the metal case. The power terminal 9 is electrically isolated from the bottom 4 and taken out. The outer periphery of the lid part 10 of the container is coated with a heat-retaining layer 11 to retain moisture.

The reason why the first positive characteristic porcelain and the second positive characteristic porcelain are electrically connected in series, and the crystal oscillator and the first positive characteristic porcelain and the second positive characteristic porcelain are not brought into contact with each other in Ik contact is , in order to increase the temperature gain of the crystal resonator, when the ambient humidity is low and the current is stable after voltage application, the resistance of the first positive characteristic porcelain is larger than the resistance of the second positive characteristic porcelain. , most of the applied voltage is applied to the first positive characteristic porcelain, and the first positive characteristic porcelain becomes the main heating element, heating the entire crystal oscillator directly, and as the ambient temperature increases. Then, the second positive characteristic porcelain senses the heat of the first positive characteristic porcelain and the temperature rise of the container due to the rise in ambient temperature, increases its resistance, and increases the ηL applied to the second positive characteristic porcelain. The ratio of pressure is increased to reduce the calorific value of the first positive characteristic porcelain.
This is because the positive characteristic porcelain directly reduces the electric power used to heat the crystal resonator, and also greatly reduces the overall heat generation amount, thereby increasing the temperature gain of the crystal resonator.

When a voltage is applied and the current is stable, when the ambient temperature is low, the first positive characteristic porcelain has a higher resistance than the second positive characteristic porcelain, and becomes the main heating element, and as the ambient temperature increases, the second positive characteristic porcelain becomes the main heating element. In order to increase the resistance of the characteristic porcelain and increase the ratio of the voltage applied to the second positive characteristic porcelain, the first
and the second positive characteristic (size, number, resistance (+k%) of each G unit.It is important to appropriately select the Curie temperature and the heat capacity of the crystal resonator and the container. It is desirable that the heat capacity be smaller than the heat capacity of .

A crystal oscillator and a first positive characteristic porcelain are attached thermally,
In addition, in order to heat-conductively attach the container and the second positive characteristic porcelain, they may be bonded using a commonly known conductive adhesive, soldered together, or pressed and fixed using a metallic spring material. Further, a commonly known method such as using an insulating adhesive or a heat conductive insulating adhesive may be used. Of course, when an electrically insulating sanitizing agent is used, the mutual electrical connection may be made by any electrical connection means such as the conventional lead wire connection method.

Although it is preferable to use one each of the first positive characteristic porcelain and the second positive characteristic porcelain from the viewpoint of sturdiness, a plurality of each may be used. For example, as shown in FIG. 2, the first positive characteristic porcelain 2.2' may be attached to both sides of the crystal resonator, or as shown in FIG. 8, a plurality of positive characteristic porcelains 5,
5' may be attached. The first positive characteristic porcelain and the second one
"The positive characteristic porcelains must be electrically in series with each other, but the first positive characteristic porcelain and the second positive characteristic porcelain may be electrically and structurally connected in series or in parallel. .

The Curie temperature of the first positive characteristic porcelain and the second positive characteristic porcelain may be the same or different.In short, the temperature of the crystal oscillator may be selected appropriately so that the temperature is not easily affected by changes in the ambient temperature. Preferably, the Curie temperature of the second Positive Characteristic porcelain is equal to the Curie temperature of the first Positive Characteristic porcelain so that the resistance of the second Positive Characteristic porcelain changes sensitively to changes in ambient temperature. It is desirable that the temperature be the same as, or preferably 5 to 15°C lower. Also, the temperature of the crystal oscillator is usually 80"
Since the Curie temperature of the positive characteristic porcelain is preferably 80°C or less, more preferably 60'C or less.

The material of the container is not limited to metal; for example, the bottom 4 of the container 8 in FIG. The entire container 8 may be made of resin or ceramic, and the entire container 8 or a portion thereof may be combined with a material 11 having good moisture retention properties. In addition, to keep warm, the container may be structured like a dewar flask (thermos flask).
After voltage is applied, it is preferable to make the heat capacity of the tea utensil larger than the heat capacity of the crystal oscillator in order to easily make the resistance of the first positive characteristic porcelain larger than the resistance of the second positive characteristic porcelain when the current is stable. , a heat sink may be added to the second positive characteristic porcelain to increase its heat capacity.

(Example) Next, an example of 6 yuzu will be described.

He -45/U crystal resonator with a diameter of 6 mm and a thickness of 1 t
n+n, 25°C (20Ω, Curie temperature 80°C).

1 positive characteristic porcelain is layered with 4 permissive porcelain, and this is 10X
A second positive characteristic porcelain of the same size, the same resistance, and the same Curie temperature is attached to the inner lower surface of the gold H41FIj container with a specialized adhesive, and then the first positive 18. Connect the characteristic porcelain and the second positive characteristic porcelain in series, and insulate the outer surface of the container with foamed silicone rubber with a thickness of 2 mm.
Apply a voltage of 5 V, ambient humidity = ao'c to +60
℃ and measured its characteristics, as shown in Figure 4 (a) l (b) l (C), at low humidity the resistance of the first 〒)-characteristic porcelain changes to the second positive characteristic. 7 of porcelain
At +60'C, it becomes 0.9 times, and the temperature of the crystal oscillator is 65°C ± 2°C1, or temperature gain 22.5.
The vibration frequency was extremely stable, below 0.5 ppm. The power consumption at this time is 0.4 W at -30°C,
It was 0.06 W at +60°C, which was very small.

In addition, if the same structure is used but only the first positive characteristic ceramic is used without using the second positive characteristic ceramic, the temperature of the crystal oscillator will be the same as that of the fourth positive characteristic ceramic.
As shown by the dotted line in Fig. 4 (DJ), the temperature gain is as small as 70''C±b゛C1, or 9;
As shown by the dotted line in C), the vibration frequency changed significantly to 1.5 ppm.

Example 2 HG --L5/Ll crystal resonator with diameter 8mm and thickness 1
Solder the first positive characteristic porcelain of 25"C at 25"C (N, Curie 7 crystal and 85°C) and connect it to lQ.
It is stored in a metal container measuring The characteristic porcelain and the second positive characteristic porcelain were electrically connected in a 1h1 row, a voltage of 18.5 V was applied, and the ambient temperature was -80
When we measured its characteristics from °C to +60°C, the 11iA degree of the crystal resonator was 65"C, or a temperature gain of about 1.
3, which was good.

In addition, the first positive characteristic porcelain and the second positive characteristic porcelain have the same structure! When they were connected in parallel, the center temperature deviated significantly from +10 75'CC, and the temperature curve decreased to 6.

Example 8 As shown in Fig. 3, a first positive characteristic porcelain with a diameter of 8 squares, a thickness of 1 mm, a resistance of 20 Ω at 25°C, and a Curie temperature of 80°C was applied to the HO-45/U crystal resonator. This was placed in a 10 x 15 x 20 am metal container, and two second special test porcelains of the same size, same Curie humidity, and same resistance were placed on the inner bottom of the metal container. A total of 8 positive temperature ceramics were electrically connected in series, and a 2 mm space was provided between the crystal resonator and the second positive temperature ceramic and the third positive temperature ceramic. When applying a voltage of IL5 V and changing the ambient temperature from -3 O''G to +60°C and measuring its characteristics, the humidity of the crystal resonator was 6
The temperature gain of 8°C±8°C1 was 15, which was extremely excellent.

Example 4 As shown in Fig. 2, 1r1 diameter 8rIm, thickness 1vrfn, 25°C were applied to both sides of a He-4.3/U crystal resonator.
A piece of first positive characteristic porcelain with a resistance of 30 Ω and a Curie temperature of 35°C was taken from conductive mff1 material (T).The whole was stored in a silicon heat 11M kt4 tube, and this was Stored in a metal container measuring 20 x 20 mm, with a diameter of 10 mm, jv-width, and 25 degrees.
A second positive characteristic porcelain with a resistance of 10Ω and a Curie temperature of 30°C is soldered, the two first positive characteristic porcelains are electrically connected in parallel, and the first positive characteristic porcelain and the second positive characteristic porcelain are Positive characteristic porcelains were electrically connected in series and their characteristics were measured at an ambient temperature of -80°C to +60°C with a paper pressure of 13.5 V applied, and the temperature of the crystal resonator was 66 ± 3. 'C1, that is, a temperature gain of 15, which was extremely excellent.

(Advantageous Effects of the Invention) As mentioned above, the present invention has the advantage that when the ambient humidity is low, the first positive characteristic value device thermally connected to the crystal oscillator directly heats the crystal oscillator. , as the circumference of 1711 fM degrees increases, the second positive characteristic porcelain electrically connected in series with the first positive characteristic porcelain will reduce the amount of heat generated by the first positive characteristic porcelain and the ambient temperature. By sensing and increasing its resistance, the first positive characteristic porcelain reduces the electric power that directly heats the crystal resonator, and acts to suppress the temperature rise of the crystal resonator. Even if the temperature changes greatly, the change in temperature Pi of the crystal resonator is extremely small, and its temperature gain can easily be increased to 10 or more. Since it is not in direct contact with the porcelain, hysteresis may occur in the vortex IW of the crystal oscillator when the ambient humidity changes, and the temperature gain will be sufficiently large due to variations in the resistance 11t of the positive characteristic porcelain manufactured by the manufacturer. The present invention provides a temperature-compensated crystal resonator that has a simple structure, is small, inexpensive, and has an unprecedentedly large temperature gain, without fear of failure, and is industrially useful.

Figure 4 [RU) 111 + Vehicle Explanation Figure 1 is a schematic sectional view of one specific example for explaining the configuration of the present invention, and Figures 2 and 3 are for explaining another example of the body of the present invention. FIG. 4 is a schematic sectional view showing the performance of an embodiment of the present invention.

■...Crystal oscillator, 2, 2'...First positive characteristic porcelain, 3...Akutajima, 4...Bottom of container, 5,5'...Second positive characteristic porcelain, 6... Connection rinse, 7.7'... Terminal of crystal oscillator, 8... Terminal of positive characteristic porcelain, 9... Terminal of positive characteristic porcelain, 10... Evil city, 11... Moisturizing Material.

Patent applicant: Asahi Denpa Co., Ltd.

Claims (1)

[Claims] 1. A first positive characteristic porcelain is thermally attached to a crystal oscillator, a second positive characteristic porcelain is thermally attached to a container for storing the first positive characteristic porcelain, and the first positive characteristic porcelain and the second positive characteristic porcelain are connected together. A crystal oscillator with temperature compensation characterized in that the crystal oscillator and the first positive characteristic porcelain and the second positive characteristic porcelain are configured to be electrically connected in series so that they do not come into direct contact with each other. Child.