JPH04222425A - Rechargeable appliance - Google Patents

Abstract

PURPOSE:To realize common use of a charger for secondary batteries, to be mounted on an appliance, having different charging currents. CONSTITUTION:In an appliance 1, a circuit 15 feeding a charging current continually and a constant current circuit 12 are inserted into a charging path for a secondary battery 11. A charger 2 feeds a charging current from a DC power supply 21 through a current detecting resistor 23 to the appliance 23. When a transistor 23 is turned ON by the voltage across the current detecting resistor 23, a LED 25 lights. Output current from the constant current circuit 12 is determined so that the LED 25 can be lighted. ON interval of the charging current is determined by the continual circuit 15 so that the average value of the charging current satisfies the specifications of the secondary battery 11.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charging device in which a secondary battery provided in the main body of the device is charged by a charger equipped with a charging display circuit.

0002

2. Description of the Related Art Conventionally, blood circulation promoting devices have been provided which promote blood circulation by applying a high frequency electric field to the human body. Since this type of blood circulation promoting device is used by being attached to the human body, it has a built-in small secondary battery as a power source, and is configured to charge the secondary battery when not in use.

The blood circulation promoting device as the main body 1 of the device is shown in FIG.
As shown in the figure, the secondary battery 11 is charged with a constant current via the constant current circuit 12, and the oscillation circuit 13 is operated using the secondary battery 11 as a power source, and the antenna 14 outputs a high frequency. has been done. On the other hand, in order to charge the secondary battery 11, a charger 2 is required, and the charger 2 is detachably connected to the device main body 1 via a charging terminal 3. The charger 2 includes a DC power source 21 made of a dry cell battery, and a charge display circuit 22 that indicates that charging is in progress. The charge display circuit 22 connects the secondary battery 1 from the DC power supply 21.
A current detection resistor 23 inserted in the charging path leading to the current detection resistor 23, a transistor 24 as a switch element that is turned on when the voltage across the current detection resistor 23 is equal to or higher than a predetermined voltage,
It consists of a light emitting diode 25 connected in series between the emitter and collector of the transistor 24 so that it lights up when the transistor 24 is turned on.

0004

[Problems to be Solved by the Invention] However, in the above configuration, since the current detection resistor 23 is inserted in the charging path, in order to prevent the voltage drop from increasing,
It is necessary to set the resistance value of the current detection resistor 23 to a small value. On the other hand, since the voltage between the base and emitter required for the transistor 24 to turn on is approximately 0.6V, the resistance value R of the current detection resistor 23 is set so that charging current x R≧0.6. There must be.

[0005] Here, when developing products in various forms, secondary batteries 11 of various sizes and capacities are used depending on specifications such as the dimensions of the main body 1 of the device and continuous use time. It is also necessary to change the charging current depending on the product. In this way, if the charger 2 is to be shared by several types of device bodies 1 with different charging currents, the charger 2 must be designed to match the device body 1 that requires the maximum charging current.

However, in such a charger 2, if the resistance value R is set to a small value in order to reduce the voltage drop due to the current detection resistor 23, when the device body 1 with a small charging current is connected, both ends of the current detection resistor 23 A problem arises in that the voltage does not exceed 0.6V and the light emitting diode 25 does not light up. Conversely, if the resistance value R of the current detection resistor 23 is set so that the light emitting diode 25 lights up even when the device body 1 with the lowest charging current is connected, the resistance value R of the current detection resistor 23 can be set so that the light emitting diode 25 lights up even when the device body 1 with the largest charging current is connected. A problem arises in that the power consumption by the current detection resistor 23 increases.

In particular, in recent years, blood circulation promoting devices have become thinner and the charging current of the main body 1 of the device has tended to become smaller. If you try to reuse the charger 2, you will need to consider the problems described above. The present invention aims to solve the above problems,
The present invention attempts to provide a charging device in which a charging display circuit operates even when a device with a small charging current is connected to a charger designed to support devices with a large charging current. be.

[0008]

[Means for Solving the Problems] In order to achieve the above object, the present invention includes a main body of a device equipped with a secondary battery that is charged via a constant current circuit, a DC power source, and a power supply to the secondary battery. In a charging device that includes a charger equipped with a charging display circuit that displays charging when the voltage across a current detection resistor inserted in the charging path is equal to or higher than a predetermined voltage, the output current value of the constant current circuit is determined by the charging display circuit. is set to an operable value, and the main body of the device is equipped with an intermittent circuit that intermittents the charging current to the secondary battery so that the average charging current meets the specifications of the secondary battery.

[0009]

[Operation] According to the above configuration, the output current value of the constant current circuit is set to a value that allows the charging display circuit to operate, and the charging current to the secondary battery is adjusted so that the average charging current matches the specifications of the secondary battery. Since the device is equipped with an intermittent circuit, the charging current to the secondary battery installed in the device is set by the intermittent circuit, and the design specifications of only the intermittent circuit can be adjusted according to the specifications of the secondary battery. By making this change, the charger and constant current circuit can be shared. In addition, since the output current value of the constant current circuit is set to a value that allows the charging display circuit to operate, the charging current can be intermittent, but the charging display circuit can be operated intermittently, and charging can be displayed. It is.

0010

[Example] In this example, a blood circulation promoting device is shown as the device main body 1, but it is not necessarily limited to this.
The technical idea of the present invention is also applicable to other electrical devices. As shown in FIG. 1, the device main body 1 includes a secondary battery 11 serving as a power source, a constant current circuit 12 inserted in a charging path to the secondary battery 11, and an intermittent circuit 15 for intermittent charging current.
It includes an oscillation circuit 13 that oscillates at a high frequency and an antenna 14 for applying a high frequency electric field to the human body. Here, the output current value of the constant current circuit 12 is set so as to correspond to the secondary battery 11 whose charging current is maximum when performing product development. For example, if the charging current of the secondary battery 11 is selected between 1 and 4 mA depending on product development, the output current value of the constant current circuit 12 is 4 mA.
It is set to mA. The intermittent circuit 15 is a circuit that intermittents the charging current at a constant frequency, and adjusts the average value of the charging current by adjusting the on-duty. That is, as shown in FIG. 2, if the output current value of the constant current circuit 12 is 4 mA, the on-duty is set to 25% when the charging current is 1 mA for the secondary battery 11 ( 2 a), when the charging current is 2 mA, it is 50% (FIG. 2 b), and when the charging current is 3 mA, it is 75% (FIG. 2 c). Further, when the charging current is 4 mA, the charging current is continuously passed as shown in d of FIG. In this case, the intermittent circuit 15 may not be provided. In FIGS. 2a, 2b, and 2c, the broken lines indicate the average charging current.

On the other hand, the charger 2 for charging the secondary battery 11 has the same structure as that explained in the section of the prior art,
It is equipped with a DC power source 21 made of a dry battery, and a charging display circuit 22 that indicates that charging is in progress. Further, it is detachably connected to the device main body 1 via the charging terminal 3. The charge display circuit 22 includes a current detection resistor 23 inserted in the charging path from the DC power supply 21 to the secondary battery 11, and a switch element that is turned on when the voltage across the current detection resistor 23 is equal to or higher than a predetermined voltage. The light emitting diode 25 is connected in series between the emitter and the collector of the transistor 24 so as to light up when the transistor 24 is turned on.

According to the above configuration, since the charging current is intermittent by the intermittent circuit 15, it is only necessary to adjust the average current to the specifications of the secondary battery 11. In addition, since the peak value of the charging current is set by the output current value of the constant current circuit 12, if this value is set to a value that allows the charging display circuit 22 to operate, it is possible to reduce the charging current while reducing the charging current. The charging display circuit 22 can also be activated. That is, the light emitting diode 25 lights up only during the charging current period. Here, the light emitting diode 25 blinks, but the frequency of the intermittent circuit 15 is changed to several tens of H.
If you set it to z or more (for example, 40Hz), there is no problem because it will appear as if it is continuously lit.

[0013]

Effects of the Invention As described above, the present invention includes a device main body equipped with a secondary battery that is charged via a constant current circuit, a DC power supply, and a current detection device inserted in the charging path to the secondary battery. In a charging device consisting of a charger equipped with a charging display circuit that displays charging when the voltage across the resistor is equal to or higher than a predetermined voltage, the output current value of the constant current circuit is set to a value that enables the charging display circuit to operate. , Since the device is equipped with an intermittent circuit that intermittents the charging current to the secondary battery so that the average charging current meets the specifications of the secondary battery, the charging current to the secondary battery installed in the device is an intermittent circuit. This has the advantage that the charger and constant current circuit can be shared by changing the design specifications of only the intermittent circuit according to the specifications of the secondary battery. In addition, since the output current value of the constant current circuit is set to a value that allows the charging display circuit to operate, the charging current can be intermittent, but the charging display circuit can be operated intermittently, and charging can be displayed. It has the advantage of As a result, on the manufacturer's side,
When manufacturing devices with different specifications, only the specifications of the intermittent circuit need to be changed, and the charger can be shared.
This makes it possible to suppress increases in manufacturing costs. In addition, on the user side, when purchasing a device with specifications different from those previously used, the user can use the conventional charger as is, and only need to purchase the device itself. It becomes.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing an embodiment.

FIG. 2 is an explanatory diagram of the operation of the embodiment.

FIG. 3 is a circuit diagram showing a conventional example that does not use an intermittent circuit.

[Explanation of symbols]

1　　　　　Device body 2 Charger 11 Secondary battery 12 Constant current circuit 15 Intermittent circuit 21 DC power supply 22 Charge display circuit 23 Current detection resistor 25 Light emitting diode

Claims (1)

[Claims] Claim 1: A device body equipped with a secondary battery that is charged via a constant current circuit, a DC power supply, and a current detection resistor inserted in the charging path to the secondary battery, the voltage across which is equal to or higher than a predetermined voltage. In a charging device consisting of a charger and a charger equipped with a charging display circuit that displays charging when A charging device comprising: an intermittent circuit for intermittent charging current to the secondary battery in accordance with the specifications of the secondary battery.