JP2002141622A - Electronic circuit board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To decrease the thermal conductivity between a temperature detection element and a circuit board, and to improve temperature measurement accuracy by the temperature detection element even if the temperature detection element having a general shape is used at it is without changing the structure of the temperature detection element itself. SOLUTION: A thermal conductivity inhibition means 6 inhibits the thermal conduction between a peripheral circuit and the temperature detection element 1, and is provided around the packaging section of the temperature detection element 1 for detecting temperature in atmosphere.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the field of electronic circuit boards used for electronic equipment, and more particularly to a technique for mounting a temperature detecting element on a board.

[0002]

2. Description of the Related Art A thermistor (Thermi) which is a temperature sensing element
The stor) is an element in which the internal resistance value changes according to the temperature and the amount of flowing current changes, and this characteristic is used for detecting the temperature of the atmosphere around the element. When this thermistor is used by mounting it on a temperature detection circuit, the heat generated from other electronic components or wiring patterns on the circuit board is transmitted to the thermistor through the circuit board and becomes higher than the ambient temperature. An error may occur in the detected temperature.

In order to prevent this, it is necessary to reduce the thermal conductivity between the thermistor and the circuit board.
There is a "rush current suppressing element" disclosed in Japanese Patent No. 3703. In this example, there is described a method of preventing the amount of current flowing through the thermistor from increasing, the temperature of the element itself increasing due to self-heating, and preventing the circuit board from being burnt or thermally degraded.

FIG. 6 shows a structural diagram thereof. 10 is a disk-shaped thermistor element, 20 is a thermistor element 10
The electrode 30 provided on both sides of the lead wire 30 is a lead wire, and the reference numeral 40 is a rolled and through-hole processed portion provided on a part of the lead wire 30.

The processing section 40 is caught in a component insertion hole of a circuit board (not shown), thereby preventing the thermistor element 10 from directly contacting the circuit board. As a result, burnout or thermal deterioration of the circuit board is prevented.

[0006]

As described above, in the conventional temperature sensing element, the processing portion 40 is formed on a part of the lead wire 30 in order to reduce the thermal conductivity between the thermistor element 10 and the circuit board. For example, the device structure is modified. For this reason, there has been a problem that the cost of parts increases due to the complicated processing shape of the lead wire 30 and the like.
In addition, there is a problem that the size of the component is increased due to the presence of the processing unit 40, and the component mounting area on the circuit board is increased.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems. Even when a temperature detecting element having a general shape is used as it is without changing the structure of the temperature detecting element itself, the temperature detecting element can be used. It is an object of the present invention to reduce the thermal conductivity between the substrate and the circuit board to improve the accuracy of temperature measurement by the temperature detecting element.

[0008]

In an electronic circuit board according to the present invention, heat conduction is suppressed around a mounting portion of a temperature detecting element for detecting the temperature of an atmosphere, which suppresses heat conduction between a peripheral circuit and the temperature detecting element. This is provided with a suppressing means.

Also, in the electronic circuit board according to the present invention, the heat conduction suppressing means has a structure in which a conductive member around a mounting portion of the temperature detecting element is partially deleted.

Further, in the electronic circuit board according to the present invention, the heat conduction suppressing means has a structure in which a board member around a mounting portion of the temperature detecting element is partially removed.

Further, in the electronic circuit board according to the present invention, heat conduction between the specific element and the temperature detecting element is conducted between the mounting section of the specific element and the mounting section of the temperature detecting element for detecting the temperature of the specific element. The heat conduction promoting means is provided.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is a perspective view of an electronic circuit board according to Embodiment 1 of the present invention. FIG.
In the drawings, 1 is a thermistor element as a temperature detecting element for detecting an ambient temperature, 2 is an electrode provided on both surfaces of the thermistor element 1, 3 is a lead wire, and 4a is a wiring pattern section for flowing a current to the thermistor element 1. Reference numeral 5 denotes a circuit board on which the thermistor is mounted, and reference numeral 6 denotes a pattern processing section as a heat conduction suppressing means by removing the metal film of each layer of the circuit board 5.

FIG. 2 shows a pattern processing section 6 according to the first embodiment.
It is sectional drawing which shows the detail of. The pattern processing portion 6 has a shape concentrically spread from a contact portion of the lead wire 3 to the circuit board 5, and has a structure in which a metal film such as a copper foil used for a wiring pattern in each layer of the circuit board 5 is deleted. It has become.
Wiring pattern part 4 for flowing current to thermistor element 1
“a” is connected to the circuit board 5 around the pattern processing section 6 from at least one place by a relatively thin pattern. Note that the wiring pattern portion 4a is for obtaining a sensing output of the thermistor element 1, and has conventionally existed.

Since the pattern processing section 6 and the wiring pattern section 4a can be formed by a normal process of manufacturing a wiring pattern of a printed circuit board, the pattern processing section 6 and the wiring pattern section 4a are formed at the stage of designing a circuit pattern. Can be easily created by considering the arrangement of

Next, the operation will be described. During circuit operation, heat is generated from electronic components or wiring patterns on the circuit board 5 around the pattern processing section 6. The pattern processing portion 6 is made of a material of the substrate itself such as epoxy resin, and the wiring pattern made of a metal film such as a copper foil having a higher thermal conductivity is omitted. It is lower. Therefore, the structure is such that heat is hardly conducted from the peripheral circuit board 5 to the thermistor element 1 through the lead wire 3.

Further, the pattern processing portion 6 has a shape concentrically spread from the contact portion of the lead wire 3 to the circuit board 5, thereby suppressing uneven heat conduction from a specific region of the peripheral circuit board 5. Thermistor element 1 through lead wire 3
Can be minimized.

Further, by forming the wiring pattern portion 4a for flowing current through the thermistor element 1 with a relatively thin pattern, the effect of heat conducted from the circuit board 5 through the wiring pattern 4a is suppressed as much as possible.

As described above, according to the first embodiment, the heat conduction suppressing means for suppressing heat conduction between the peripheral circuit and the thermistor element 1 is provided around the mounting part of the thermistor element 1 for detecting the temperature of the atmosphere. Since the pattern processing section 6 is provided, the thermal conductivity around the thermistor element 1 can be reduced, and the temperature rise of the thermistor element 1 due to heat conducted through the circuit board 5 can be suppressed.
, The accuracy of measuring the ambient temperature can be improved.

Further, according to the first embodiment, the pattern processing section 6 includes the circuit board 5 around the mounting section of the thermistor element 1.
Since the metal film of each layer is partially removed, the temperature rise of the thermistor element 1 due to heat conducted through the metal film having high thermal conductivity can be suppressed with a simple structure.

Embodiment 2 FIG. 3 is a perspective view of an electronic circuit board according to Embodiment 2 of the present invention. Embodiment 1
In the above, the pattern processing portion 6 in which the metal film of each layer of the circuit board 5 is removed is formed around the thermistor. However, in the second embodiment, as shown in FIG. By forming the groove structure 7 as a suppressing means and adopting a structure for interrupting heat conduction between the circuit board 5 and the thermistor, even lower thermal conductivity is realized.

FIG. 4 is a sectional view showing details of the groove structure 7 of the second embodiment. The circuit board 5 around the thermistor is cut into a groove shape and connected to the circuit board 5 around the groove structure 7 at at least one location. The wiring pattern portion 4a for flowing a current to the thermistor element 1 is connected to a peripheral circuit through a connection portion of the periphery of the groove structure portion 7 with the circuit board 5.

Since such a groove structure 7 can be formed by a normal manufacturing process of drilling a printed circuit board, it is easy to consider the arrangement of the groove structure 7 in the design stage of the circuit board 5. Can be created.

By partially removing the circuit board 5 around the thermistor mounting portion by the groove structure portion 7, heat conducted from the circuit board 5 around the groove structure portion 7 to the thermistor element 1 is almost blocked. And lower thermal conductivity can be achieved. For this reason, even if the groove structure 7 is brought close to the vicinity of the lead wire 3, the temperature rise of the thermistor element 1 through the lead wire 3 can be suppressed to a minimum. Therefore, the size of the groove structure 7 can be reduced, and the mounting area can be reduced.

As described above, according to the second embodiment, a substrate member around the mounting portion of the thermistor element 1 is partially deleted as a means for suppressing heat conduction between the peripheral circuit and the thermistor element 1. Since the groove structure 7 is provided, the thermal conductivity around the thermistor element 1 can be further reduced, and the temperature rise of the thermistor element 1 due to heat conducted through the circuit board 5 can be further suppressed. The accuracy of measuring the ambient temperature by the element 1 can be further improved.

Embodiment 3 In the first or second embodiment, the case of measuring the ambient temperature with a thermistor has been described. However, the thermistor can be used for measuring the temperature of other electronic components. In such a case, conventionally, a method has been adopted in which a thermistor is arranged near the electronic component for which temperature is to be measured, and the radiant heat from the electronic component to the atmosphere is detected by the thermistor. there were.

In the third embodiment, an example in which the temperature of a remote electronic component is measured with high accuracy by a thermistor will be described.
FIG. 5 is a perspective view of an electronic circuit board according to Embodiment 3 of the present invention. Reference numeral 4b denotes a wiring pattern portion arranged as a heat conduction promoting means, and reference numeral 8 denotes a measured electronic component whose temperature is measured by a thermistor.

The heat generated in the electronic component 8 to be measured is conducted through the wiring pattern portion 4 b and reaches the thermistor element 1 through the lead wire 3. Further, since the pattern processing portion 6 as the heat conduction suppressing means described in the first embodiment exists around the thermistor mounting portion, heat conduction from the peripheral circuit board 5 is suppressed. That is, the thermistor element 1
Only the heat from the electronic component 8 to be measured
Since the electric current is conducted through b, the temperature of the measured electronic component 8 can be measured with high accuracy.

Further, regarding the temperature of the electronic component 8 to be measured remote from the thermistor element 1, the wiring pattern 4
Since the measurement can be performed with high accuracy by the arrangement of b,
The degree of freedom of component mounting is improved.

In FIG. 5, the wiring pattern portion 4b also functions as the wiring pattern portion 4a for obtaining the sensing output of the thermistor element 1 in FIG. 1 of the first embodiment or FIG. 3 of the second embodiment. Although an example is shown, the wiring pattern portion 4a and the wiring pattern portion 4b may be separately arranged.

Further, the wiring pattern portion 4b as the heat conduction promoting means is made of a material such as silver having higher heat conductivity than ordinary copper, or has a larger sectional area than usual, so that it can be covered. Heat conduction between the measurement electronic component 8 and the thermistor element 1 can be further promoted, and the temperature of the electronic component 8 to be measured can be measured with higher accuracy.

As described above, according to the third embodiment, the electronic component 8 to be measured is placed between the mounting portion of the electronic component 8 to be measured and the mounting portion of the thermistor element 1 for detecting the temperature of the electronic component 8 to be measured. Since the wiring pattern portion 4b provided as a heat conduction promoting means for promoting heat conduction between the thermistor element 1 and the thermistor element 1 is provided, the temperature of the electronic component 8 to be measured remote from the thermistor element 1 can be measured with high accuracy. And the degree of freedom in mounting components on the circuit board 5 is improved.

In the first to third embodiments, an example of an electronic circuit board on which a thermistor is mounted as a temperature detecting element has been described. However, other temperature measuring resistance elements (elements whose resistance value changes with temperature) and The present invention may be applied to an electronic circuit board on which a temperature detecting element such as a thermocouple (an element whose electromotive force changes with temperature) is mounted. In this case, the same effect can be obtained.

[0033]

As described above, the present invention is configured as described above, and has the following effects.

[0034] According to the electronic circuit board of the present invention, around the mounting portion of the temperature detecting element for detecting the temperature of the atmosphere,
A heat conduction suppressing means for suppressing heat conduction between the peripheral circuit and the temperature detecting element is provided, so that the thermal conductivity around the temperature detecting element can be reduced, and temperature detection by heat conducted through the substrate can be performed. There is an effect that the temperature rise of the element can be suppressed and the accuracy of measuring the ambient temperature by the temperature detecting element can be improved.

Further, according to the electronic circuit board of the present invention, the heat conduction suppressing means has a structure in which the conductive member around the mounting portion of the temperature sensing element is partially deleted, so that the heat conduction suppressing means has a low thermal conductivity. There is an effect that the temperature rise of the temperature detecting element due to heat conducted through the high conductive member can be suppressed with a simple structure, and the accuracy of measuring the ambient temperature by the temperature detecting element can be improved.

Further, according to the electronic circuit board of the present invention, the heat conduction suppressing means has a structure in which the board member around the mounting portion of the temperature detecting element is partially removed, so that the temperature detecting element peripheral portion is removed. The heat conductivity of the part can be further reduced, the temperature rise of the temperature sensing element due to the heat conducted to the substrate can be further suppressed, and the accuracy of measuring the ambient temperature by the temperature sensing element can be further improved. There is.

According to the electronic circuit board of the present invention, the heat conduction between the specific element and the temperature detecting element is provided between the mounting section of the specific element and the mounting section of the temperature detecting element for detecting the temperature of the specific element. Is provided with a heat conduction promoting means for promoting the temperature, so that the temperature of a specific element remote from the temperature detecting element can be measured, and the degree of freedom in mounting the element on the electronic circuit board is improved. .

[Brief description of the drawings]

FIG. 1 is a perspective view of an electronic circuit board according to Embodiment 1 of the present invention.

FIG. 2 is a sectional view showing details of a pattern processing section according to the first embodiment of the present invention.

FIG. 3 is a perspective view of an electronic circuit board according to Embodiment 2 of the present invention.

FIG. 4 is a sectional view showing details of a groove structure according to a second embodiment of the present invention.

FIG. 5 is a perspective view of an electronic circuit board according to Embodiment 3 of the present invention.

FIG. 6 is a structural diagram showing an example of a conventional temperature sensing element.

[Explanation of symbols]

1 thermistor element, 2 electrodes, 3 lead wires, 4a
Wiring pattern section, 4b wiring pattern section, 5 circuit board,
6 pattern processing part, 7 groove structure part, 8 electronic component to be measured, 10 thermistor element, 20 electrodes, 30 lead wire, 40 processing part

Claims (4)

[Claims] An electronic circuit board, comprising: a heat conduction suppressing means for suppressing heat conduction between a peripheral circuit and the temperature detecting element around a mounting portion of a temperature detecting element for detecting a temperature of an atmosphere. . 2. The electronic circuit board according to claim 1, wherein the heat conduction suppressing means has a structure in which a conductive member around a mounting portion of the temperature detecting element is partially removed. 3. The electronic circuit board according to claim 1, wherein the heat conduction suppressing means has a structure in which a board member around a mounting portion of the temperature detecting element is partially removed. 4. A heat conduction promoting means for promoting heat conduction between the specific element and the temperature detecting element, between the mounting part of the specific element and the mounting part of the temperature detecting element for detecting the temperature of the specific element. An electronic circuit board, comprising: