JP2002075469A - Battery heat retaining device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery heat retaining device from which a necessary output can be taken out even at low temperature by preventing a lowering of a battery capacity. SOLUTION: A sheet heater 3 heated by electric conduction is mounted to a rechargeable main battery 1, and a temperature sensor 4 detecting the temperature of the main battery 1 is installed. When the temperature detected by the temperature sensor 4 is lower than a certain temperature, electricity is applied from a spare battery 8 to the sheet heater 3 by a controller 10, and the main battery 1 is heated by the heat of the sheet heater 3. By the above, the temperature of the main battery 1 is properly maintained and the lowering of battery capacity is prevented even in winter.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery warming device for keeping a rechargeable battery mounted on a battery forklift or the like at a predetermined temperature.

[0002]

2. Description of the Related Art A battery forklift is equipped with a battery for supplying power to various devices mounted on a vehicle body such as a traveling motor and a hydraulic motor. This battery is a rechargeable battery, and is charged by a charger when the capacity is reduced.

[0003] When a battery forklift is used outdoors in the cold in winter or in a cold storage, the temperature of the battery is remarkably lowered and the capacity is reduced. For this reason, when the forklift requires a large amount of power, a situation arises in which the capacity of the battery is insufficient and a predetermined output cannot be obtained.

Therefore, conventionally, the temperature is measured while the battery is being charged, and when the temperature is low, the battery charging time is lengthened to extend the gassing time, or supplemented at regular intervals during use of the forklift. The battery was being charged.

[0005]

However, if the temperature of the battery is too low, the battery fluid may freeze. In such a case, the battery is not charged even if charging is continued. . Further, even when the battery can be normally charged, it is inevitable that the capacity of the battery decreases due to the decrease in the temperature of the battery.

An object of the present invention is to solve the above-mentioned problems, and an object of the present invention is to provide a battery warming device capable of preventing a decrease in battery capacity even when the temperature is low and capable of extracting a required output.

[0007]

In order to solve the above-mentioned problems, the present invention provides a heat retaining member which is heated by energization to keep a battery at a predetermined temperature, and a temperature sensor which detects a temperature of the battery, When the temperature detected by the temperature sensor is lower than a certain value, the heat retaining member is energized (claim 1).

In this way, when the temperature of the battery drops, the temperature sensor detects this and energizes the heat retaining member to heat the heat retaining member, so that the heat keeps the battery constant. It is kept warm at the temperature. This prevents a decrease in capacity due to a decrease in battery temperature,
The necessary output can be always taken out.

[0009] In a battery composed of an aggregate of a plurality of cells, such as a battery mounted on a battery forklift, for example, a seat heater can be used as a heat retaining member. In this case, the seat heater may be interposed between the plurality of cells (claim 2).

[0010] As a power source of the heat retaining member, a spare battery may be provided to supply power to the heat retaining member from the spare battery (claim 3), or the heat is retained by the heat retaining member without providing the spare battery. Power may be supplied from the battery (main battery) itself to the heat retaining member. When a spare battery is provided, power consumption of the main battery can be saved, and when power is supplied by the main battery itself, the spare battery is not required and the configuration is simplified.

When a spare battery is provided in addition to the main battery, a main battery charger and a spare battery charger are provided. When the voltage of the main battery becomes low, the battery is charged by the main battery charger. When it becomes low, control may be performed so that the battery is charged by the spare battery charger (claim 4). According to this, automatic charging can be performed when the voltage of the battery drops. Further, by controlling both the main battery charger and the spare battery charger by the control means, the spare battery can be simultaneously charged when the main battery is charged.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an electrical configuration diagram showing one embodiment of a battery heat retaining device according to the present invention. In the figure, reference numeral 1 denotes a rechargeable main battery mounted on a battery forklift, which is composed of an aggregate of a plurality of cells 2. Reference numeral 3 denotes a sheet heater as a heat insulating member interposed between the cells 2, and is interposed at two locations so as to contact all the cells 2 in this example. This seat heater 3 is
A heater that generates heat when energized is built in, and is covered with a member having chemical resistance (particularly, sulfuric acid) so as not to corrode even when battery fluid leaks. Reference numeral 4 denotes a temperature sensor attached to the main battery 1 for detecting the temperature of the battery, and is composed of, for example, a thermistor. 5 is a positive terminal of the main battery 1 and 6 is a negative terminal.

Reference numeral 7 denotes a main battery charger for charging the main battery 1, reference numeral 8 denotes a spare battery for energizing the seat heater 3, and the spare battery 8 comprises a rechargeable battery similarly to the main battery 1. Is done. 9
Is a spare battery charger for charging the spare battery 8, and 10 is a controller as control means for controlling energization of the seat heater 3 and charging of the batteries 1 and 8.
The positive side of the spare battery 8 is electrically connected to one end of the seat heater 3, and the negative side of the spare battery 8 is electrically connected to the other end of the seat heater 3 via the controller 10. The temperature sensor 4, the main battery charger 7, and the spare battery charger 9 are connected to the controller 10.

FIG. 2 is an electric block diagram specifically showing the configuration of the controller 10. As shown in FIG. 11 is an automatic charge switch for automatically charging the main battery 1 and the spare battery 8; 12 is a charge end switch for terminating charging of each battery; and 13 is the main battery 1 kept warm by the seat heater 3. Battery insulation switch for Each of these switches is connected to the controller 1
0 is provided on the operation panel.

A control unit 14 includes a CPU, a memory (ROM and RAM), an input / output interface,
/ D converter and the like. The control unit 14 receives signals from the automatic charge switch 11, the charge end switch 12, and the battery warming switch 13, and outputs the main battery temperature from the temperature sensor 4, the main battery voltage from the main battery 1, A spare battery voltage from the battery 8 is input. The temperature and voltage are converted into digital signals by the A / D converter of the control unit 14.

Reference numeral 15 denotes a semiconductor switch that performs an on / off operation based on an output signal from the control unit 14, and controls energization and non-energization of the spare heater 8 to the seat heater 3. An output signal is also provided from the control unit 14 to the main battery charger 7 and the spare battery charger 9, and the charging of the main battery 1 and the spare battery 8 is controlled by the controller 10.

FIG. 3 is a flowchart showing the control operation of the controller 10. Hereinafter, the operation of keeping and charging the battery will be described with reference to FIG. First, the control unit 14 controls the automatic charging switch 11 and the charging end switch 1
2, the state of the battery insulation switch 13 is read (step S1), and then the main battery temperature from the temperature sensor 4, the main battery voltage from the main battery 1, and the spare battery voltage from the spare battery 8 are read (step S1). Step S2).

Next, it is determined whether or not the automatic charging switch 11 is turned on based on the information read in step S1 (step S3). If the automatic charging switch 11 is on, a main battery flag (hereinafter referred to as MAIN)
FLG) and a spare battery flag (hereinafter referred to as S
UB FLG) is set to 1 (step S4). If the automatic charging switch 11 is off, each flag is not set. Subsequently, it is determined whether or not the charge end switch 12 is turned on (step S5). If the charge end switch 12 is on, MAI
N FLG and SUB FLG are each reset to 0 (step S6). If the charge end switch 12 is off, each flag is not reset.

Next, it is determined whether or not the battery insulation switch 13 is turned on (step S7). If the battery insulation switch 13 is on, the temperature of the main battery 1 detected by the temperature
It is determined whether the temperature is lower than ° C (step S8). When the battery temperature is lower than 10 ° C., an ON signal is output from the control unit 14 to the semiconductor switch 15 in FIG. Based on this signal, the semiconductor switch 15 is turned on, thereby forming an energizing circuit from the spare battery 8 to the seat heater 3, and energizing the seat heater 3 (step S9). As a result, the seat heater 3 generates heat, and this heat is transmitted to the cells 2 constituting the main battery 1, so that the battery 1 is warmed and kept at a predetermined temperature.

On the other hand, when the battery temperature is equal to or higher than 10 ° C., the semiconductor switch 15 is turned off and the power to the seat heater 3 is not conducted (step S10).
In addition, even when the battery insulation switch 13 is turned off in step S7, power is not supplied to the seat heater 3. The temperature of 10 ° C. is an example, and other temperature values may be used as a reference. The energization time to the seat heater 3 may be adjusted by, for example, a timer.

Next, the operation proceeds to the automatic charging operation of the battery. First, it is determined whether or not MAIN FLG is set to 1 (step S11). If MAIN FLG is 1, the automatic charging switch 11 is on, so it is determined whether the voltage value of the main battery 1 is lower than 59 V (step S12). This value of 59 V is also an example, and can be set to an arbitrary value. If the voltage value is lower than 59V, a drive signal is output from control unit 14 to main battery charger 7 in FIG.
Is charged (step S13). On the other hand, if the voltage value is 59 V or more, there is no need to charge, and thus the main battery 1 is not charged (step S14).
Also, even if MAIN FLG is not set to 1 in step S11, the main battery 1 is not charged.

Next, it is determined whether or not SUB FLG is set to 1 (step S15). SUB F
If LG is 1, the automatic charging switch 11 is on, and the voltage of the backup battery 8 is subsequently set to 14V.
It is determined whether it is lower (step S16). This one
The value of 4 V is also an example, and can be set to an arbitrary value.
If the voltage value is lower than 14V, the control unit 14 shown in FIG.
Outputs a drive signal to spare battery charger 9, and in response, spare battery charger 9 charges spare battery 8 (step S17). On the other hand, if the voltage value is 14 V or more, there is no need to charge, so that the spare battery 8 is not charged (step S18).
Also, even if SUB FLG is not set to 1 in step S15, the spare battery 8 is not charged. After executing steps S17 and S18, the process returns to step S1 to repeat the above-described operation.

As described above, in the above-described embodiment, when the temperature of the main battery 1 drops below a predetermined value, the temperature sensor 4 detects this and the power is supplied to the seat heater 3 from the spare battery 8. The main battery 1 is kept at a constant temperature by the heat generated in the seat heater 3. For this reason, even in a place such as a cold outdoors or a cold storage in winter, the capacity of the battery 1 does not decrease and a necessary output can be taken out, so that the capacity of the forklift does not decrease. Further, since the main battery 1 can be used at a normal temperature, overcharging and overdischarging do not occur, and the life of the battery can be extended.

Further, since power is supplied to the seat heater 3 by the spare battery 8, the main battery 1
Is not consumed for the seat heater 3, and the main battery 1 can use 100% of the power for its intended use (such as driving a motor). In addition, the provision of the automatic charging switch 11 allows the chargers 7 and 9 to automatically charge the main battery 1 and the spare battery 8 when the battery voltage drops. Further, since both the main battery charger 7 and the spare battery charger 9 are controlled by the controller 10, the spare battery 8 is charged when the main battery 1 is charged.
Can also be charged at the same time.

In the above embodiment, the main battery 1
Although a spare battery 8 for the seat heater 3 is provided separately, the spare battery 8 is not always essential, and the main battery 1 can be used as a power source for the seat heater 3. FIG. 4 is an electrical configuration diagram showing the embodiment in this case. 4, the same parts as those in FIG. 1 are denoted by the same reference numerals. In FIG. 4, the positive terminal 5 of the main battery 1 is electrically connected to one end of the seat heater 3, and the other end of the seat heater 3 is connected to the negative terminal 6 of the main battery 1 via the controller 10. ing.
The temperature sensor 4 and the main battery charger 7 are connected to the controller 10.

FIG. 5 shows the configuration of the controller 10 of FIG. 4, which is basically the same as FIG. However, there is no voltage input from the spare battery 8 and no output to the spare battery charger 9. The spare battery 8 in FIG. 2 is replaced with the main battery 1. The other parts are the same as those in FIG. 2, and the same parts are denoted by the same reference numerals and description thereof will be omitted.

FIG. 6 is a flowchart showing the operation of the controller 10 of FIG. 5, which is also basically the same as FIG. However, the spare battery voltage is not read in step S2, and S
There is no setting or resetting of UB FLG. Steps S15 to S18 in FIG. 3 are omitted. The other steps are the same as those in FIG. 3, and thus the same steps are denoted by the same reference numerals and description thereof will be omitted.

Also in the embodiments of FIGS. 4 to 6, when the temperature of the main battery 1 decreases, the temperature sensor 4 detects this, and the semiconductor switch 15 is turned on.
Electric power is supplied from the main battery 1 to the seat heater 3. As a result, the main battery 1 is kept at a constant temperature by the seat heater 3. The spare battery 8
Since there is no spare battery charger 9, the configuration is simplified.

When the spare battery 8 is provided, the spare battery charger 9 is not provided, and if the capacity of the spare battery 8 decreases, the power supply to the seat heater 3 is performed from the spare battery 8 to the main battery 1. A configuration for switching may be used.

In each of the above embodiments, the main battery 1
As a set of a plurality of cells 2,
The battery of the present invention is not limited to this, and may be constituted by a single cell. Further, in the above, the seat heater 3 has been described as an example of the heat retaining member, but the heat retaining member of the present invention is not necessarily a sheet-like member, and may be, for example, a columnar heater. Further, the temperature sensor 4 may be attached to the battery, or may be arranged near the battery at a distance. Further, the device of the present invention can be applied not only to a forklift but also to an automatic guided vehicle equipped with a battery.

[0031]

According to the present invention, when the temperature of the battery drops, the temperature sensor detects this and energizes the heat retaining member, so that the battery is kept at a constant temperature by the heat of the heat retaining member. You. Therefore, it is possible to prevent a decrease in capacity due to a decrease in temperature of the battery, and to secure a necessary output. In addition, since the battery can be used in the normal temperature range, overcharge and overdischarge can be suppressed, and the life of the battery can be extended.

[Brief description of the drawings]

FIG. 1 is an electrical configuration diagram of a battery warming device according to the present invention.

FIG. 2 is an electric block diagram of a controller.

FIG. 3 is a flowchart showing a control operation of a controller.

FIG. 4 is an electrical configuration diagram showing another embodiment of the present invention.

FIG. 5 is an electric block diagram of a controller according to another embodiment.

FIG. 6 is a flowchart illustrating a control operation of a controller according to another embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main battery 2 cell 3 Seat heater (insulation member) 4 Temperature sensor 7 Main battery charger 8 Spare battery 9 Spare battery charger 10 Controller (control means) 11 Automatic charge switch 12 Charge end switch 13 Battery insulation switch 14 Control unit 15 Semiconductor switch

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) H02J 7/10 H02J 7/10 B

Claims (5)

[Claims] A rechargeable battery; a heat retaining member that is heated by energization to keep the battery at a predetermined temperature; a temperature sensor that detects a temperature of the battery; and a temperature sensor that detects the temperature of the battery. Control means for controlling energization of the heat retaining member, wherein the control means energizes the heat retaining member when the temperature detected by the temperature sensor is lower than a predetermined value. 2. The battery heat retaining device according to claim 1, wherein said heat retaining member comprises a seat heater, and is interposed between a plurality of cells constituting the battery. 3. The battery according to claim 1, wherein the battery is a main battery, and a spare battery for supplying power to the heat retaining member is provided separately from the main battery, and power supply from the spare battery to the heat retaining member is controlled by the control means. 2. The battery warming device according to 1. 4. A main battery charger for charging a main battery and a spare battery charger for charging a spare battery, wherein the control means is provided when the voltage of the main battery becomes lower than a predetermined value. 4. The battery warming apparatus according to claim 3, wherein the main battery charger charges the main battery, and the spare battery charger charges the spare battery when the voltage of the spare battery becomes lower than a predetermined value. . 5. The battery warming device according to claim 1, wherein the battery is a main battery, and the main battery itself supplies power to the warming member.