JPS63234825A - Driving apparatus of electric equipment - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to an operating device for electrical equipment using a storage battery as a power source.

(Prior Art) In recent years, various electrical devices (fans,
(Vacuum cleaners, power tools, etc.) are being made cordless in order to improve their handling and portability. As a power source for such cordless electrical equipment, in consideration of running costs and the like, storage batteries that can be reused by being charged are widely used.

(Problems to be Solved by the Invention) When a storage battery is used as a power source as described above, if over-discharge progresses significantly, performance deterioration and a shortened life span of the storage battery will be caused. In particular, if a lead-acid battery is left in an over-discharged state, the lead sulfate generated inside it may become passivated and may not recover to its original state even after charging. It becomes necessary to replace the storage battery with a new one. Therefore, in reality, it is necessary to take measures to prevent over-discharging of storage batteries in electrical equipment. For this reason,
Conventionally, countermeasures have been taken, such as providing electrical equipment with a monitor lamp that dims as the output voltage of a storage battery decreases, thereby notifying a state in which the output voltage has decreased. However, such passive measures are less reliable in preventing overdischarge of the storage battery, and as a result, the conventional configuration has the problem of extremely high possibility of deteriorating the performance and shortening the lifespan of the storage battery. there were.

The present invention has been made in view of the above circumstances, and its purpose is to automatically cut off power supply to the load when the output voltage of the storage battery that serves as the power source of the load becomes less than a predetermined lower limit value. An object of the present invention is to provide an operating device for an electrical device that can reliably prevent over-discharging of a storage battery, and also eliminates chattering during the above-mentioned cut-off operation.

[Structure of the Invention] (Means for Solving the Problems) The present invention is directed to an operating device for electrical equipment using a storage battery as a power source, and in which a current-carrying path is formed between the storage battery and a load in an operating state. A relay having a relay contact that detects the voltage, and a voltage detection means for detecting the output voltage of the storage battery on the load side of the relay contact, and a relay that is turned on only when operated to connect between the voltage detection means and the storage battery. A power-on switch to be connected is provided, and further, when the power-on switch is turned on, the relay is turned on only when the voltage detected by the voltage detection means is equal to or higher than a predetermined lower limit value to self-maintain the relay in an operating state. This configuration includes a switching element that allows the

(Function) When the power supply switch is turned on in a state where the output voltage of the storage battery is equal to or higher than a predetermined lower limit value, the switching element is turned on. Then, the relay is self-maintained in an operating state, and in response, a current-carrying path is formed between the storage battery and the load, and the load is driven. Additionally, when the output voltage of the storage battery drops below the lower limit value as a result of driving such a load, the switching element is turned off and the self-holding state of the relay is released, cutting off the current-carrying path between the storage battery and the load. and the drive of the load is stopped.

At this time, the output voltage of the storage battery will recover to above the lower limit value in response to the drive stop of the load, but since the relay has released its self-holding state, the above-mentioned cutoff operation of the energized path may cause chattering. will disappear.

(Example) Hereinafter, an example in which the present invention is applied to an electric fan will be described with reference to the drawings.

In FIG. 2, an electric fan 1, which is an electrical device, is constructed by having a fan head 3 standing upright on a base 2, and each base 2 has an automatic return type that is turned on only when a suppression operation is performed. Power on switch 4 and power cut off switch 5
is provided.

In FIG. 1 showing the electrical configuration, 6 is a storage battery that serves as a power source for the electric fan 1, which is connected to a commercial AC power source (not shown).
It is provided so that it can be charged through a C adapter 7 and a charging circuit 8. Note that the AC adapter 7 has plugs 7a and A.
It consists of a C-DC converter 7b.

Reference numeral 9 denotes a relay having a relay contact 9a and an excitation coil 9b, and the relay contact 9a is provided so as to selectively open and close a current-carrying path between the storage battery 6 and the fan motor 10 serving as a load. Further, the power supply switch 4 is connected in parallel to the relay contact 9a. The excitation coil 9b has one end connected to the positive side of the storage battery 6 via the relay contact 9a, and the other end connected to the storage battery 6 via the collector-emitter of a transistor 11 (NPN type) serving as a switching element. connected to the negative side of the Note that a flywheel diode 12 is connected in parallel to the exciting coil 9b.

13 is a voltage detection means, which detects the output voltage Vd of the storage battery 6.
is provided so as to be detected on the load side of relay contact 9a. Specifically, this voltage detection means 13 is constructed by connecting a series circuit of a resistor 14°, a voltage regulator diode 15, and a resistor 16 in parallel with the fan motor 10, and a series circuit of a voltage regulator diode 15 and a resistor 16 connected in parallel. The connection point is connected to the base of the transistor 11. At this time, the breakdown voltage Vz of the voltage regulator diode 15 is
This corresponds to the predetermined lower limit value in the present invention, and is equal to the output voltage Vd of the storage battery 6 when the input terminal of the fan motor 10 falls to a state unsuitable for the electric fan 1 and before the storage battery 6 reaches overdischarge. It is set.

Note that the power cutoff switch 5 is connected between the base and emitter of the transistor 11.

Next, the action of -1- structural acid will be explained with reference to FIG. 3, which shows the temporal change characteristics of the output voltage Vd of the storage battery 6. The electric fan 1 is used with the AC adapter 7 removed. Therefore, when the power supply switch 4 is turned on with the storage battery 6 fully charged, that is, with the output voltage Vd of the storage battery 6 being higher than the breakdown voltage Vz of the voltage regulator diode 15, the Voltage diode 15 breaks down. Then, transistor 11
Since the base current flows, the transistor 11 is turned on, and the excitation coil 9b of the relay 9 is switched from the storage battery 6 to the power-on switch 4. Current is applied through the transistor 11, and the relay contact 9a is turned on in response. As a result, even after the on-operation of the power-on switch 4 is released, a current-carrying path for the excitation coil 9b is formed.
Relay 9 is self-maintained in the operating state. When the relay 9 is self-held, an energizing path is formed between the storage battery 6 and the fan motor 10, and the fan motor 10
is now driven. When such driving is continued for a long time, the output voltage Vd of the storage battery 6 gradually decreases as shown in FIG. 3. Then, time t in Fig. 3
When the output voltage Vd becomes lower than the breakdown voltage Vz of the voltage regulator diode 15 at o, the voltage regulator diode 15
is cut off and transistor 11 is turned off. Then, the self-holding state of the relay 9 is released and the relay contact 9
Since a is turned off, the energizing path between the storage battery 6 and the fan motor 10 is cut off, and the fan motor 10 is stopped. When the fan motor 10 is stopped in this way, the output voltage Vd of the storage battery 6 recovers as shown in FIG. Since the means 13 does not function, the operation of interrupting the current-carrying path by the relay contact 9a does not cause chattering. Note that the portion indicated by the broken line in FIG. 3 is the discharge characteristic when the fan motor 10 continues to be energized. Further, when driving the fan motor 10 to be stopped, the power cutoff switch 5 is turned on. Then, the base and emitter of the transistor 11 are short-circuited and turned off, so that the self-holding state of the relay 9 is released and the fan motor 10 is stopped in the same way as described above.

In short, according to the present embodiment described above, when the output voltage Vd of the storage battery 6 becomes less than the breakdown voltage Vz of the voltage regulator diode 15, which is the predetermined lower limit value, that is, when the storage battery 6
The energizing path of the fan motor 10 is automatically cut off before the storage battery 6 becomes over-discharged, thereby reliably preventing over-discharge of the storage battery 6. Therefore, there is no risk of performance deterioration and shortened lifespan of the storage battery 6 due to over-discharge, as in the conventional case. Further, an automatic reset type power-on switch 4 and a relay 9 that forms a current conduction path for the fan motor in a self-holding state are provided, and a voltage detection means for detecting the output voltage Vd of the storage battery 6 on the load side of the relay contact 9a. 13 and the transistor 11 that controls the self-holding state of the relay 9 based on the detected voltage, the above-mentioned relay contact 9a does not cause chattering in the operation of interrupting the current-carrying path. It is possible to extend the life of the contact 9a.

In the above embodiment, a constant voltage diode 15 is provided in the voltage detection means 13, but this is provided to ensure the operation of the transistor 11, and the voltage dividing between the resistors 14 and 16 is Depending on the voltage, transistor 11
The on/off control is possible. Therefore, the constant voltage diode 15 may be provided as necessary.

In addition, the present invention is not limited to the embodiments described above and shown in the drawings, and may be applied not only to electric fans but also to general electrical equipment such as vacuum cleaners and power tools without departing from the gist thereof. It can be implemented with various modifications within the range.

[Effects of the Invention] According to the present invention, as is clear from the above explanation, in an operating device for electrical equipment using a storage battery as a power source, when the output voltage of the storage battery becomes less than a predetermined lower limit value, the load is Energization can be automatically cut off, thereby reliably preventing over-discharge of the storage battery, thereby eliminating the risk of deterioration of its performance and shortening its lifespan, as well as eliminating chattering during the above-mentioned cutoff operation, extending the lifespan of the contacts. It has excellent effects such as:

[Brief explanation of drawings]

The drawings show one embodiment of the present invention; FIG. 1 is a wiring diagram, FIG. 2 is a perspective view of the electric fan, and FIG. 3 is a discharge characteristic diagram for explaining the operation. In the figure, 1 is a fan (electrical appliance), 4 is a power on switch, 5 is a power cutoff switch, 6 is a storage battery, 9 is a relay, 9a is a relay contact, 9b is an excitation coil, and 10 is a fan motor (load) , 11 is a transistor (switching element), 13 is a voltage detection means, and 15 is a constant voltage diode. Applicant Toshiba Corporation Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] 1. In an operating device for electrical equipment in which the power source for a load is obtained from a storage battery, there is provided a relay having a relay contact that forms an energizing path between the storage battery and the load in an operating state, and an output voltage of the storage battery that is connected to the relay contact. a voltage detecting means provided to detect on the load side of the voltage detecting means; a power supply switch configured to be an automatic return type that turns on only when operated, and connecting the voltage detecting means and the storage battery in the on state; a switching element configured to be turned on only when the voltage detected by the voltage detection means is equal to or higher than a predetermined lower limit value when the power supply switch is turned on, and to self-maintain the relay in an operating state in response to the turning on; An operating device for electrical equipment, characterized by comprising: