JPH0545084Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention relates to a charger that controls the charging of a battery to be charged, and particularly relates to a charger equipped with a heat detection element for detecting heat generation in the battery. be.

(Prior art) This type of charger detects the battery voltage to control the charging current when charging the battery, and also reduces the charging current when the battery temperature exceeds a predetermined value during charging. It is equipped with a heat detection element for performing so-called temperature correction. By the way, in order to detect the temperature of the battery using such a heat detection element, conventionally the heat detection element has been mounted at the position of the printed wiring board as shown in Fig. 4 or Fig. 5 a and b. .

In FIG. 4, a heat detection integrated circuit 1 as a heat detection element is mounted with the battery 2, which is a heat detection object, on the same surface of a printed wiring board 3, with the battery 2 close to each other,
The heat of the battery 2 is being detected.

However, when the heat detection integrated circuit 1 is mounted on a printed wiring board 3 as shown in FIG. 4, heat generation from electronic components 4 such as transistors mounted near the heat detection integrated circuit 1 causes Thermal detection integrated circuit 1 is affected and targeted battery 2
It tends to be difficult to accurately detect heat.

Next, in FIGS. 5a and 5b, a printed wiring board 12 on which electronic components (not shown) are mounted is attached to the housing 11 of the charger. The battery 13, which is the object to be detected by heat, is not mounted on the printed wiring board 12, but is fixed to the housing 11. Terminals of the battery 13 are connected to the printed wiring board 12 via lead wires 14. The heat detection integrated circuit 15 is a film-like flexible printed wiring board 1 attached to a printed wiring board 12.
It is implemented in 6. The portion of the flexible printed wiring board 16 on which the heat detection integrated circuit 15 is mounted is in close contact with the battery 13, and the heat detection integrated circuit 15 detects the heat of the battery 13.

However, when mounting components as shown in FIGS. 5a and 5b, the heat detection integrated circuit 15 is located away from the electronic components mounted on the printed wiring board 12, so heat generated by the electronic components Although the influence is less, flexible printed wiring board 1
6 is likely to cause disconnection of the printed wiring due to heat generation from the battery 13, and therefore, a defective charger is likely to occur, and the flexible printed wiring board 16
There is also a tendency for costs to increase.

(Purpose of the invention) The present invention solves the above-mentioned technical problems, suppresses defects due to disconnection, reduces cost increase, and allows the heat detection element to accurately detect heat of the battery, which is the object to be detected. The purpose is to provide chargers.

(Structure of the invention) The invention provides a control circuit component and a battery as a heat detection object on one side of a printed wiring board, and a heat detection element on the other side of the printed wiring board facing the battery. Furthermore, a through hole is formed in the printed wiring board to pass between the battery and the heat detection element.

With this configuration, most of the heat from the battery is applied to the heat detection element through the through hole formed in the printed wiring board, so that the heat generation state of the battery can be detected with high accuracy.

(Example) Fig. 1 is a tilted view of the printed wiring board, control circuit components, and battery of the charger according to the first embodiment of the present invention, and Fig. 2 is a diagram showing the vicinity of the through hole of the printed wiring board shown in Fig. 1. FIG. 3 is a cross-sectional view for explaining the structure.

On one side of the printed wiring board 21, a capacitor 22a, resistors 22b, 22c, 22d, 22
Control circuit components such as e and transistor 22f are mounted, and a battery 23 that is charged by a control circuit formed by the control circuit components is provided. A copper foil wiring pattern 24 for forming the control circuit is formed on the other surface (pattern surface) of the printed wiring board 21. In a region on the other side of the printed wiring board 21 facing the battery 23 provided on one side of the printed wiring board 21, a heat detection integrated circuit 25 serving as a heat detection element of the battery 23 is located at a positive electrode position than the center position of the battery 23. It is mounted shifted toward the 23a side. In addition, a through hole 21 a is formed in the printed wiring board 21 and passes between the heat detection integrated circuit 24 and the battery 23 . By providing such a through hole 21a, the heat detection integrated circuit 2
Heat conduction between the battery 23 and the battery 23 is performed efficiently.

According to this first embodiment, since the positive electrode side of the battery 23 generates more heat due to its structure and chemical reaction than the negative electrode side, the heat detection integrated circuit 25 is connected to the battery 23.
By shifting the battery 23 toward the positive electrode 23a of No. 3, a rise in the temperature of the battery 23 can be reliably detected.

FIG. 3 is a cross-sectional view of the vicinity of the through hole of the printed wiring board included in the charger according to the second embodiment of the present invention.

In FIG. 3, a battery 23 is disposed on one side of a printed wiring board 31, and a copper foil wiring pattern 32 is formed on the other side. Further, the printed wiring board 31 has two through holes 31a, 31
A heat detection integrated circuit 25 is provided on the other surface of the printed wiring board 31 located between the through holes 31a and 31b. The through hole 31
There is enough space between a and 31b to allow a sufficient amount of adhesive 33 for bonding the heat detection integrated circuit 25 to the printed wiring board 31.

According to this second embodiment, the printed wiring board 3
Two through holes 31a, 31 divided into 1
By forming the through holes 31a and 31b
In addition, the thickness of the adhesive prevents the heat detection integrated circuit 25 from closing the through holes 31a and 31b, so that the heat generated from the battery 23 does not penetrate through the holes 31a and 31b. Hole 31
The heat is efficiently transmitted to the heat detection integrated circuit 25 via the heat waves a and 31b, and the heat generation state of the battery 23 can be detected with high accuracy.

(Effects of the invention) As described above, according to the invention, the battery and control circuit components as the object to be detected by heat are provided on one side of the printed wiring board, and the heat detection element is placed opposite the battery on the other side. Further, the printed wiring board is provided with a through hole passing through between the heat detection element and the battery, so that most of the heat generated from the battery is transmitted to the heat detection element through the through hole. Moreover, the heat of the control circuit components has little effect on the heat detection element, and therefore, the heat detection element can accurately detect the heat generation state from the battery without increasing the cost and preventing defects caused by disconnection as in the past. It can be detected well.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a printed wiring board, control circuit components, and battery included in a charger according to a first embodiment of the present invention, and FIG. 2 is a cross section of the printed wiring board of the first embodiment near the through hole. 3 is a sectional view of the vicinity of the through hole of the printed wiring board provided in the charger according to the second embodiment of the present invention, and FIG. 4 is a sectional view of the printed wiring board, control circuit components, and battery of the conventional charger. A perspective view, FIG. 5a, and a top view of the printed wiring board and battery of another conventional charger, FIG. 5b.
5 is a sectional view taken along the cutting line - shown in FIG. 5a. 21, 31...Printed wiring board, 21a, 3
1a, 31b...through hole, 22a...capacitor (control circuit component), 22b, 22c, 22d, 22
e...Resistor (control circuit component), 22f...Transistor (control circuit component), 23...Battery, 25...
...Thermal detection integrated circuit (thermal detection element).

Claims (1)

[Claims for Utility Model Registration] 1. A control circuit component and a battery as a heat detection object are provided on one side of a printed wiring board, and a heat detection element is provided on the other side of the printed wiring board facing the battery. . The charger further characterized in that the printed wiring board is provided with a through hole passing between the battery and the heat detection element. 2. The charger according to claim 1, wherein the heat detection element is disposed on the other surface of the printed wiring board, shifted toward the positive electrode from the center of the battery. 3. A utility model registration request characterized in that two of the through holes are formed in the printed wiring board, and the heat detection element is adhesively fixed to the other surface of the printed wiring board located between the two through holes. The charger described in item 1.