JPH0765868A - Battery device - Google Patents

Abstract

PURPOSE:To eliminate a discharge circuit so as to prevent a memory effect by providing a plurality of nickel cadmium secondary batteries (nickcad battery), and successively performing an operation for using the battery of the least electric capacity charged after a complete discharge. CONSTITUTION:In a discharge condition, from voltages of two nickcad batteries 12, 13 detected by voltage checkers 14, 15, an electric capacity is always calculated in a control part 17. The nickcad battery judged for its electric capacity small by the control part 17 is used for a discharge by a selective switch 16 and switched to the other nickcad battery after a complete discharge, simultaneously with displaying in an information display part 6. When a charged condition is detected by connecting a rectifier circuit, the switch 16 is thrown the control part to a side of the nickcad battery to be charged. Even in a charging condition, the electric capacity of the nickcad battery is calculated in the control part by a voltage value of the voltage checker, and when judged a complete charge, ending the charge is displayed to inhibit the charge by placing the switch 16 in an opened condition. Accordingly, a memory effect is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a camera-integrated VTR,
The present invention relates to a battery device used in electronic devices such as an electric razor and a mobile phone, and particularly to a battery device including a nickel-cadmium secondary battery (hereinafter referred to as a nicad battery).

[0002]

2. Description of the Related Art A conventional battery device of this type, for example, a battery device used in a camera-integrated VTR will be described below with reference to FIG.

In FIG. 2, 1 is a battery device, 2 is a nickel-cadmium nickel-cadmium battery, 3 is a voltage checker for detecting the electric capacity of the nickel-cadmium battery 2, 4 is a discharge circuit for completely discharging the nickel-cadmium battery 2, 5 is a charging / discharging detection unit for detecting whether the battery device 1 is in a charging state or a discharging state, and 6 is a notification display for indicating that by charging an LED when charging is required or when charging is completed. And 7 are the voltage checker 3 or the charge / discharge detector 5
The control units 8 and 9 for controlling the discharge circuit 4 and the notification display unit 6 on the basis of the output of 1 are positive and negative terminals for charging or discharging, respectively.

In the battery device constructed as described above, the voltage of the nickel-cadmium battery 2 is constantly detected by the voltage checker 3, and the controller 7 constantly judges whether or not the electric capacity of the nickel-cadmium battery 2 is sufficient. is doing. When the control unit 7 determines that the electric capacity of the nickel-cadmium battery 2 is insufficient and needs to be charged, the control unit 7 instructs the notification display unit 6 to perform a notification display prompting charging.

In order to perform the notification display operation for urging the notification display unit 6 to be charged, it is necessary to supply power enough to operate the entire battery device 1. For that purpose, the NiCd battery 2 which is the power source is used. The above-mentioned notification display operation must be executed in a state before the complete discharge.

The user recognizes from the notification display that the battery device 1 needs to be charged, and connects the plus terminal 8 and the minus terminal 9 of the battery device 1 to a rectifying power source (not shown).

At this time, if the nickel-cadmium battery 2 is charged without being fully discharged, the nickel-cadmium battery 2 stores the discharge completion point and is discharged only to the stored discharge capacity at the next discharge. A memory effect will occur. Therefore, when the charging / discharging detection unit 5 detects that the battery device 1 is in a charged state, the discharge circuit 4 first completely discharges the nickel-cadmium battery 2 to prevent the memory effect.

When the voltage checker 3 detects that the nickel-cadmium battery 2 is completely discharged, the control unit 7 causes the discharge circuit 4 to discharge.
The operation of is stopped and the nickel-cadmium battery 2 is charged. Then, when the charging is completed, the control unit 7 instructs the notification display unit 6 to perform a notification display operation informing that the charging is completed. At this time, there is also proposed a configuration in which the control unit 7 performs a notification display operation and, at the same time, forcibly cancels the charging operation in order to prevent overcharge of the nickel-cadmium battery 2.

The user recognizes from the notification display that the battery device 1 has been charged, and connects the battery device 1 to the load of the camera-integrated VTR (not shown) that uses the battery device 1 to bring it into a discharged state. . By repeating the above-described operations and operations, the battery operation of the camera-integrated VTR is performed.

[0010]

However, in the case of the conventional battery device, a discharge circuit is incorporated in order to prevent the memory effect, and therefore the circuit structure of the battery device is only complicated. In addition, there is a problem that the charging time including the discharging time by the discharging circuit increases. Furthermore, the discharge of the NiCd battery by the discharge circuit is intended only to prevent the memory effect,
There is a problem of wasting energy.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a battery device which prevents a memory effect and does not require a discharge circuit.

[0012]

A battery device according to the present invention is a battery device including a nickel-cadmium nickel-cadmium battery, wherein at least two or more nickel-cadmium batteries are provided and the electric capacity of each nickel-cadmium battery is increased. An electric capacity detecting means for detecting, a charging / discharging detecting means for detecting a charging or discharging state of the battery device, and a selection switch for selecting a desired one of the two or more nicad batteries at the time of charging or discharging. A control means for switching the selection switch based on the detection output of the capacitance detection means or the charge / discharge detection means is provided.

[0013]

In the battery device according to the present invention, when discharging, a nicad battery having the smallest electric capacity is used, and when the nicad battery is sufficiently discharged, another nicad battery is used for discharging. In addition, at the time of charging, only the completely discharged NiCd battery is charged, so that the memory effect can be prevented.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the battery device of the present invention will be described below with reference to FIG. 1 for a battery device used in a camera-integrated VTR. The description is omitted.

In FIG. 1, 11 is a battery device and 1
Reference numerals 2 and 13 denote first and second nicad batteries, 14 is a first voltage checker for detecting the electric capacity of the first nicad battery 12, and 15 is a second voltage checker for detecting the electric capacity of the second nicad battery 13. Voltage checker 16 is a selection switch for selecting a desired one of the above two nickel-cadmium batteries 12 and 13,
Reference numeral 17 denotes a control unit including a general-purpose one-chip microcomputer that controls the selection switch 16 and the notification display unit 6 based on the outputs of the first and second voltage checkers 14 and 15 or the charge / discharge detection unit 5.

In the above structure, the charge / discharge detection unit 5
As a method of detecting the above, a method of mechanically detecting the connection state of the battery device 11 or a method of allowing the user to switch between charging and discharging with a changeover switch can be considered.

When the battery device 11 configured as described above is in a discharged state, the voltages of the first and second nickel-cadmium batteries 12 and 13 are measured by the first and second voltage checkers 14 and 15, respectively. The electric capacities of the first and second nickel-cadmium batteries 12 and 13 are constantly calculated, and the control unit 17 constantly calculates the electric capacities from the battery characteristics. Further, the control unit 17 determines the NiCd battery having the smaller electric capacity and controls the selection switch 16 so that the NiCd battery having the smaller electric capacity is used for discharging.

Then, in the discharge state, the control unit 17
When it is determined that the NiCd battery used for discharging is completely discharged, the selection switch 16 is switched to the other NiCd battery side and used for discharging. At the same time, the control unit 17
Instructs the notification display unit 6 to perform a notification display for prompting charging of the completely discharged nicad battery.

When the user recognizes the notification display prompting the charging, the user disconnects the battery device 11 from the load of the camera-integrated VTR (not shown) in order to bring the battery device 11 into the charging state, and the charging or discharging terminal. 8 and 9 are connected to a rectifier circuit (not shown). The charging / discharging detection unit 5 detects that the battery device 11 is in a charged state, and the control unit 17 switches the selection switch 16 to the NiCd battery side to be charged. At this time, the battery device 11 is
Even if the selection switch 16 is switched to the completely discharged Ni-Cd battery side, it is possible to operate by the power of the rectifier circuit (not shown).

The electric capacity of the NiCd battery being charged is
It is constantly calculated by the control unit 17 based on the voltage value from the voltage checker, and when the control unit 17 determines that the electric capacity of the NiCd battery being charged is sufficient and the battery is fully charged, the notification display of the end of charging is displayed. At the same time as instructing the unit 6, the selection switch 16 is opened to prohibit charging and prevent overcharging.

The user recognizes that the charging is completed by the notification display, and the battery 11 is rectified by a rectifying circuit (not shown).
Then, it is connected again to the load of the camera-integrated VTR (not shown) to bring it into a discharging state. By repeating the charging and discharging as described above, the battery system of the camera-integrated VTR is constructed.

In the above embodiment, the detachable battery device for the camera-integrated VTR which requires the battery operation has been described. However, the battery device of the electronic device built-in type and the rectifier circuit are built-in. Of course, it may be a battery device that is installed.

[0023]

In the battery device according to the present invention, the memory effect can be prevented by charging only the completely discharged secondary battery among at least two or more secondary batteries. A preventive discharge circuit is not required, and therefore, the circuit configuration can be simplified, and measures for heat generation due to the load of the discharge circuit are not required, and the cost can be reduced. Further, since the discharging by the discharging circuit is not necessary, the total time required for charging can be shortened.

Also, the charged energy can be effectively used without discharge by the discharge circuit, that is, wasteful energy consumption.

[Brief description of drawings]

FIG. 1 is a block circuit diagram showing an embodiment of a battery device of the present invention.

FIG. 2 is a block circuit diagram showing a conventional battery device.

[Explanation of symbols]

 5 Charge / Discharge Detecting Section 6 Notification Display Section 8 Positive Terminal for Charging or Discharging 9 Negative Terminal for Charging or Discharging 11 Battery Device 12 First Ni-Cd Battery 13 Second Ni-Cd Battery 14 First Voltage Checker 15 Second Voltage checker 16 Selection switch 17 Controller

Claims (1)

[Claims] 1. A battery device comprising a nickel-cadmium secondary battery, comprising at least two or more secondary batteries, and an electrical capacity detecting means for detecting an electrical capacity of each secondary battery, A charging / discharging detection means for detecting a charging / discharging state of the battery device, a selection switch for selecting a desired one of the two or more secondary batteries at the time of charging / discharging, and the electric capacity detecting means or charging. A battery device comprising control means for switching and controlling the selection switch based on a detection output of the discharge detection means.