Charging device

Claim 2

A battery charging device comprising a constant current source, a plurality of circuit lines each for connecting the constant current source with each of batteries to be disposed, a switch circuit for controlling the supply of current from the constant current source to the respective battery, a full-charge detection means for detecting the fully charged state of the respective battery, a switching control circuit for switching successively said circuit lines one after another to be charged from the constant current source to each of the batteries, a series transistor inserted into the circuit lines between the constant current source and each of the batteries, a comparison circuit which compares the terminal voltage of the battery and the output voltage of the constant current source to turn the series transistors into an off-state when the terminal voltage of the battery is higher than the output voltage of the constant current source, and a short-circuit detection circuit for switching the condition of the switching control circuit by detecting that the battery connection terminal is short-circuited.

Claim 3

A battery charging device comprising a constant current source, a plurality of circuit lines each for connecting the constant current source with each of batteries to be disposed, a switch circuit for controlling the supply of current from the constant current source to the respective battery, a full-charge detection means for detecting the fully charged state of the respective battery, a switching control circuit for switching successively said circuit lines one after another to be charged from the constant current source to each of the batteries, a source control circuit for maintaining the source voltage of the switching control circuit when the battery connection terminal is short-circuited, and including a series transistor inserted into the circuit lines between the constant current source and each of the batteries, a control transistor for controlling the condition of said series transistor and a Zener diode connected between the base of the control transistor and the side of the constant current source in each of the circuit lines, and a short-circuit detection circuit for switching the condition of the switching control circuit by detecting that the battery connection terminal is short-circuited.

Claim 4

A battery charging device comprising a constant current source, a plurality of circuit lines each for connecting the constant current source with each of batteries to be disposed, a switch circuit for controlling the supply of current from the constant current source to the respective battery, a full-charge detection means for detecting the fully charged state of the respective battery, a switching control circuit for switching successively said circuit lines one after another to be charged from the constant current source to each of the batteries, a source control circuit for maintaining the source voltage of the switching control circuit when the battery connection terminal is short-circuited, and including a series transistor inserted into the circuit lines between the constant current source and each of the batteries, a control transistor for controlling the condition of said series transistor and a Zener diode connected between the base of the control transistor and the side of the constant current source in each of the circuit lines, and a short-circuit detection circuit for switching the condition of the switching control circuit by detecting that the battery connection terminal is short-circuited.

Claim 5

A battery charging device comprising a constant current source, a plurality of circuit lines each for connecting the constant current source with each of batteries to be disposed, a switch circuit for controlling the supply of current from the constant current source to the respective battery, a full-charge detection means which detects, through detection of the drop by a predetermined level of an output from the constant current source for charging the respective battery, that said battery is fully charged, a discrimination means for discriminating whether or not said battery is over-discharged on the basis of the initial voltage of the output of the constant current source immediately after the start of the charging to said battery, whereby the start of the detection by said full-charge detection means is able to change in accordance with the result of the discrimination by the discrimination means, a short-circuit detection circuit for discriminating whether or not the respective battery is short-circuited by the voltage level detected at a connection terminal of the respective battery, and a switching control circuit for switching successively said circuit lines one after another to be charged from the constant current source to teach of the batteries in the case where the respective battery is detected to be short-circuited by the short-circuit detection circuit while the detection order signal is generated.

Claim 6

A battery charging device comprising a constant current source, a plurality of circuit lines each for connecting the constant current source with each of batteries to be disposed, a switch circuit for controlling the supply of current from the constant current source to the respective battery, a full-charge detection means which detects, through detection of the drop by a predetermined level of an output from the constant current source for charging the respective battery, that said battery is fully charged, a discrimination means for discriminating whether or not said battery is over-discharged on the basis of the initial voltage of the output of the constant current source immediately after the start of the charging to said battery, whereby the start of the detection by said full-charge detection means is able to change in accordance with the result of the discrimination by the discrimination means, a short-circuit detection circuit for discriminating whether or not the respective battery is short-circuited by the voltage level detected at a connection terminal of the respective battery, and a switching control circuit for switching successively said circuit lines one after another to be charged from the constant current source to teach of the batteries in the case where the respective battery is detected to be short-circuited by the short-circuit detection circuit while the detection order signal is generated.

Claim 7

The battery charging device as defined in claims 1, wherein includes a delay circuit for delaying a switching signal for controlling said switch circuit until the terminal voltage of the respective battery reaches near the stationary state to form a detection order signal.

Claim 8

The battery charging device as defined in Claim 2, wherein includes a delay circuit for delaying a switching signal for controlling said switch circuit until the terminal voltage of the respective battery reaches near the stationary state to form a detection order signal.

Claim 9

The battery charging device as defined in Claim 3, wherein includes a delay circuit for delaying a switching signal for controlling said switch circuit until the terminal voltage of the respective battery reaches near the stationary state to form a detection order signal.

Claim 10

The battery charging device as defined in Claim 1, wherein includes a switch means which is turned on when each of batteries to be disposed is connected to an output of the constant current source, a rising detection circuit which detects the rising of an output from said switch means, and a signal forming circuit which forms an initially set signal on the basis of an output generated from said rising detection circuit, whereby the switching control circuit is set in the initial state by said initially set signal.

Claim 11

The battery charging device as defined in Claim 2, wherein includes a switch means which is turned on when each of batteries to be disposed is connected to an output of the constant current source, a rising detection circuit which detects the rising of an output from said switch means, and a signal forming circuit which forms an initially set signal on the basis of an output generated from said rising detection circuit, whereby the switching control circuit is set in the initial state by said initially set signal.

Claim 12

The battery charging device as defined in Claim 3, wherein includes a switch means which is turned on when each of batteries to be disposed is connected to an output of the constant current source, a rising detection circuit which detects the rising of an output from said switch means, and a signal forming circuit which forms an initially set signal on the basis of an output generated from said rising detection circuit, whereby the switching control circuit is set in the initial state by said initially set signal.

Claim 13

The battery charging device as defined in Claim 1, wherein includes a first short-circuit detection circuit which detects the charging voltage reaches a first reference voltage within a first period of time, a second short-circuit detection circuit which detects that the charging voltage reaches a second reference voltage which is higher than said first reference voltage within a second period of time which is sufficiently longer than said first period of time.

Claim 14

The battery charging device as defined in Claim 2, wherein includes a first short-circuit detection circuit which detects the charging voltage reaches a first reference voltage within a first period of time, a second short-circuit detection circuit which detects that the charging voltage reaches a second reference voltage which is higher than said first reference voltage within a second period of time which is sufficiently longer than said first period of time.

Claim 15

The battery charging device as defined in Claim 3, wherein includes a first short-circuit detection circuit which detects the charging voltage reaches a first reference voltage within a first period of time, a second short-circuit detection circuit which detects that the charging voltage reaches a second reference voltage which is higher than said first reference voltage within a second period of time which is sufficiently longer than said first period of time.

Claim 16

The battery charging device as defined in Claim 1, wherein includes an abnormal-charging detection circuit which makes detection whether the respective battery is charged in an abnormal condition, and a display means which makes distinguishing display of the condition of the respective battery whether the battery is abnormally charged or the battery is fully charged.

Claim 17

The battery charging device as defined in Claim 2, wherein includes an abnormal-charging detection circuit which makes detection whether the respective battery is charged in an abnormal condition, and a display means which makes distinguishing display of the condition of the respective battery whether the battery is abnormally charged or the battery is fully charged.

Claim 18

The battery charging device as defined in Claim 3, wherein includes an abnormal-charging detection circuit which makes detection whether the respective battery is charged in an abnormal condition, and a display means which makes distinguishing display of the condition of the respective battery whether the battery is abnormally charged or the battery is fully charged.

Claim 19

The battery charging device as defined in Claim 1, wherein includes a battery and constant current source detection circuit for turning said series transistors on only when said constant current source is connected at the given position.

Claim 20

The battery charging device as defined in Claim 2, wherein includes a battery and constant current source, detection circuit for turning said series transistors on only when said constant current source is connected at the given position.

Claim 21

The battery charging device as defined in Claim 3, wherein includes a series transistors inserted into each of the circuit lines between the constant current source and each of the batteries, and a battery and constant current source detection circuit for turning said series transistor on only when said constant current source is connected at the given position.