Electrical apparatus and start-up method

Abstract

To provide an electrical apparatus capable of suppressing the melting of a fuse during start-up, and a start-up method.SOLUTION: An electric apparatus includes a heat generating section, a fuse, and a controller. The heat generating section receives power from a current supply section, which is a power source, a commercial power source or an alternating-current power source, to generate heat. The fuse is provided between a power supply section and the heat generating section. The controller controls the power supplied to the heat generating section via a power supply path. The controller executes start-up processing for the heat generating section. The start-up processing for the heat generating section includes start processing of starting the supply of the output to the heat generating section, and interruption processing of interrupting the supply of the power to the heat generating section.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to an electric device and a starting method thereof. [Background technology]

[0002] Patent Document 1 discloses a technology for extending the life of a power conversion device by using a fuse. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 11-144603 Summary of the Invention [Problem to be solved by the invention]

[0004] Patent Document 1 does not disclose any measures to prevent damage to electrical equipment by controlling the power supply to the electrical equipment, including fuses.

[0005] An object of the present invention is to provide an electric device and a startup method that can suppress fuse blowout during startup. [Means for solving the problem]

[0006] The electrical device according to the present invention comprises a heat generating unit, a fuse, and a control unit. The heat generating unit generates heat by receiving power from a current supply unit (power source, commercial power source, or AC power source). The fuse is provided in a power supply path between the power supply unit and the heat generating unit. The control unit controls the power supplied to the heat generating unit via the power supply path. The control unit executes a start-up process for the heat generating unit. The start-up process for the heat generating unit includes a start process for starting the supply of power to the heat generating unit, and an interruption process for interrupting the supply of power to the heat generating unit. Effect of the Invention

[0007] According to the present invention, it is possible to provide an electric device and a startup method that can suppress the blowing of a fuse during startup. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram illustrating a configuration of an electrical device according to an embodiment of the present invention. [Diagram 2] FIG. 4 is a diagram showing a drive circuit for the heat generating unit. [Diagram 3] FIG. 2 is a diagram illustrating a configuration of a control device. [Figure 4] FIG. 1 is a diagram showing the resistance-temperature characteristics of a PTC heater. [Diagram 5] FIG. 1 is a diagram showing current-time characteristics of a PTC heater. [Figure 6] FIG. 11 is a diagram showing changes in heat generation temperature and power consumption of a PTC heater. [Figure 7] FIG. 1 is a diagram showing a calculation formula for obtaining (I2T-t) of the (I2T-t) characteristic. [Figure 8] FIG. 13 is a diagram showing a method for determining a fuse. [Figure 9A] FIG. 13 is a diagram showing a change in current value when power supply is not interrupted in the comparative example. [Figure 9B] 6 is a diagram showing a change in current value when power supply is cut off in the electrical device according to the embodiment. FIG. [Figure 10] 4 is a flowchart showing a control method (start-up method) of an electrical device according to the present embodiment. [Figure 11] 4 is a flowchart showing a control method (start-up method) of an electrical device according to the present embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are designated by the same reference characters, and redundant description will not be repeated.

[0010] An electric device 1 according to the present embodiment will be described with reference to Figures 1 to 3. An example of the electric device 1 is an air purifier 2 having a heating function.

[0011] Hereinafter, the description of the electric device 1 applies to the air purifier 2, and the description of the air purifier 2 applies to the electric device 1.

[0012] Fig. 1 is a schematic diagram showing the configuration of an electric device 1 according to this embodiment. Fig. 2 is a diagram showing a drive circuit for a heat generating portion 11. Fig. 3 is a diagram showing the configuration of a control device 13.

[0013] As shown in FIG. 1, an electrical device 1 according to this embodiment includes a heat generating portion 11, an intake port 14, a motor 15, a filter 16, a fan 17, and an exhaust port 18.

[0014] An air purifier 2, which is an example of the electrical device 1, will be described.

[0015] The air purifier 2 includes, for example, a cylindrical housing.

[0016] The motor 15 is a drive unit for the fan 17 and drives the fan 17 to rotate.

[0017] The outside air drawn in by the fan 17 is exhausted from the exhaust port 18 .

[0018] In the fan mode, the heating unit 11 is turned off. The air drawn in by the fan 17 passes through the filter 16 and is exhausted from the exhaust port 18.

[0019] In the hot air mode, the heating unit 11 is ON. The intake air drawn in by the fan 17 passes through the filter 16, is heated by the heating unit 11, and is then discharged from the exhaust port 18.

[0020] In the electric device 1 according to this embodiment, an example of the heat generating section 11 is a PTC heater 110 (Positive Temperature Coefficient Thermal-Resistor).

[0021] The heat generating unit 11 generates heat upon receiving power from the power supply unit 10. An example of the power supply unit 10 in this embodiment is a commercial power source. The electrical device 1 in this embodiment includes, as an example, an outlet plug (not shown). When the outlet plug is inserted into a receptacle (not shown) which is a wall outlet, a power supply path L is formed between the power supply unit 10 and the heat generating unit 11.

[0022] AC power (50 Hz and 60 Hz, 100 V) can be supplied from the power supply unit 10 to the heat generating unit 11 via the power supply path L. Note that the power supply unit 10 is not limited to a commercial power source, and may be another power supply device or a power conversion device.

[0023] The electric device 1 includes a fuse 12. The fuse 12 is provided in a power supply path L between the power supply unit 10 and the heat generating unit 11. Specifically, the fuse 12 is provided in the power supply path L between an outlet plug and the heat generating unit 11. The fuse 12 protects the electric device 1 by melting when an overcurrent flows through the power supply path L.

[0024] Further, the power supply path L is provided with a switch 101. The switch 101 is provided between the fuse 12 and the heat generating portion 11 in the power supply path L. The switch 101 makes the power supply path L conductive and cuts it off by turning on and off.

[0025] That is, when the switch 101 is in an on state, power can be supplied from the power supply unit 10 to the heat generating unit 11. When the switch 101 is in an off state, power cannot be supplied from the power supply unit 10 to the heat generating unit 11.

[0026] The switch 101 of the present embodiment is, for example, an a-contact type (normally open type) electromagnetic relay. The on and off of the switch 101 is controlled by a control unit 133, which will be described later, controlling a current I flowing through an electromagnetic coil M.

[0027] 3, the electric device 1 according to the present embodiment includes a control device 13. The control device 13 includes a current detection unit 130, a calculation unit 131, a storage unit 132, a control unit 133, and an air blowing control unit 134.

[0028] The current detection unit 130 detects the current value of the starting current flowing through the fuse 12 and the heat generating unit 11 .

[0029] The calculation unit 131 calculates the calculated Joule integral value based on the current value of the startup current. That is, when the power supply unit 10 supplies the startup current to the fuse 12 and the heat generating unit 11, the calculation unit 131 calculates the calculated Joule integral value.

[0030] The calculation unit 131 can be realized, for example, by an ASIC (Application Specific Integrated Circuit).

[0031] The storage unit 132 stores therein a reference Joule integral value calculated for each time that has elapsed since the power supply unit 10 started to supply an activation current to the fuse 12 and the heat generating unit 11 .

[0032] The storage unit 132 includes a storage device and stores data and computer programs. Specifically, the storage unit 132 includes a main storage device such as a semiconductor memory, a semiconductor memory, and an auxiliary storage device such as a hard disk drive.

[0033] Specifically, the control unit 133 includes a processor such as a CPU (Central Processing Unit). The processor of the control unit 133 executes a computer program stored in the storage device of the storage unit 132 to control the operation of each part of the electric device 1.

[0034] The air blowing control unit 134 controls the rotation of the fan 17 by the motor 15 .

[0035] The control unit 133 is configured to control the power supplied from the power supply unit 10 to the heat generating unit 11 via the power supply path L. Specifically, the control unit 133 controls the on and off of a switch 101 provided on the power supply path L to control the power supplied from the power supply unit 10 to the heat generating unit 11.

[0036] 2, when the control unit 133 turns on the switch 101, a current flows through the electromagnetic coil M of the switch 101, and the contacts are closed. When the control unit 133 turns off the switch 101, the flow of the current I to the electromagnetic coil M of the switch 101 stops, and the contacts are opened.

[0037] The control unit 133 may directly supply a current to the electromagnetic coil M of the switch 101, or may supply a current to the electromagnetic coil M of the switch 101 from a power supply circuit such as a regulator.

[0038] The control unit 133 is configured to execute a startup process to start the heat generating unit 11. In this embodiment, the startup of the heat generating unit 11 refers to a process until the heat generating state of the heat generating unit 11 is stabilized. Since the heat generating unit 11 in this embodiment is a PTC heater 110, the resistance value of the heat generating unit 11 after heat generation is greater than the resistance value of the heat generating unit 11 before heat generation. Therefore, when the heat generating unit 11 is started, a peak current greater than that when the heat generating state of the heat generating unit 11 is stable is generated.

[0039] In this embodiment, the control unit 133 controls the power supplied to the heat generating unit 11 based on the calculation result of the calculation unit 131 in the start-up process of the heat generating unit 11 .

[0040] The startup process executed by the control unit 133 includes a start process, an interruption process, and a resume process. In the startup process, the control unit 133 executes the start process, the interruption process, and the resume process in this order.

[0041] The start process is a process in which the control unit 133 turns on the switch 101 in a stopped state in which the heat generating unit 11 is not generating heat, thereby starting the supply of power from the power supply unit 10 to the heat generating unit 11.

[0042] The interruption process is a process in which the control unit 133 turns off the switch 101 after the start process, thereby interrupting the power supply from the power supply unit 10 to the heat generating unit 11.

[0043] According to this embodiment, it is possible to prevent the fuse 12 from melting when the heat generating unit 11 is started up.

[0044] Furthermore, in this embodiment, the control unit 133 turns off the switch 101 when the calculated Joule integral value, which is the calculation result of the calculation unit 131, is about to exceed the reference Joule integral value.

[0045] Specifically, after the start process, the control unit 133 compares the calculated Joule integral value with the interruption threshold. The interruption threshold is set to be smaller than the reference threshold and larger than the calculated Joule integral value. Then, when the calculated Joule integral value exceeds the interruption threshold, the control unit 133 turns off the switch 101.

[0046] By turning off switch 101, power supply path L is interrupted, which also interrupts the current flowing through fuse 12. Before the calculated Joule integral value reaches the reference Joule integral value, the increase in the calculated Joule integral value is stopped.

[0047] The control unit 133 continues the interruption process for a predetermined time. When the predetermined time has elapsed since the start of the interruption process, the control unit 133 turns on the switch 101 to execute a restart process for restarting the power supply from the power supply unit 10 to the heat generating unit 11.

[0048] When the power supply to the heat generating unit 11 is resumed, the heat generating unit 11 also resumes generating heat, and the temperature of the heat generating unit 11 rises to a temperature according to the power supplied from the power supply unit 10 .

[0049] During a period in which the power supply from power supply unit 10 is interrupted, no current flows through heat generating unit 11 and fuse 12, so that heat generation by heat generating unit 11 and fuse 12 stops and the temperatures drop. Fuse 12 has a smaller mass and a smaller heat capacity than heat generating unit 11, so the temperature drop during the period in which the power supply is interrupted is greater.

[0050] Therefore, it can be considered that the interruption process has reset the count of the calculated Joule integral value, which is the melting condition for fuse 12, or that the calculated Joule integral value has decreased.

[0051] The time for which the interruption process is continued is preferably a time during which the temperature of fuse 12 has dropped sufficiently and the drop in temperature of heat generating portion 11 is relatively small, for example, about 5 to 10 seconds.

[0052] According to this embodiment, the startup process of the heat generating unit 11 includes an interruption process for interrupting the power supply, thereby preventing the calculated Joule integral value from reaching the reference Joule integral value during the start process and restart process in which the power supply unit 10 is supplying power to the heat generating unit 11.

[0053] According to this embodiment, it is possible to suppress the blowing of the fuse 12 when starting up the heat generating unit 11. For example, when the ambient temperature before starting up the heat generating unit 11 is low, such as below freezing, the time required for starting up the heat generating unit 11 may be longer than that at room temperature.

[0054] Even in such a case, the startup process of the heat generating unit 11 includes an interruption process for interrupting the power supply, thereby preventing the calculated Joule integral value from reaching the reference Joule integral value, and thus preventing the fuse 12 from blowing.

[0055] The drive circuit for heat generating unit 11 shown in FIG. 2 supplies 600 W of power from power supply unit 10 to heat generating unit 11, for example.

[0056] When the switch 101 is OFF, the power supply path L is interrupted, and no power is supplied from the power supply unit 10 to the heat generating unit 11. Therefore, the PTC heater 110 of the heat generating unit 11 does not generate heat.

[0057] When power of, for example, 12V is applied to the switch 101 from the power supply unit 10 (microcomputer), the control unit 133 supplies power to the power supply path L, and the switch 101 turns ON. Current taken from the outlet is supplied to the PTC heater 110 of the heat generating unit 11 via the switch 101, and the PTC heater 110 generates heat.

[0058] When the switch 101 is turned on and a large current is supplied to the PTC heater 110 for a long time, a large amount of energy is applied to the fuse 12. When the amount of energy applied to the fuse 12 exceeds a threshold value, the fuse 12 melts.

[0059] Therefore, the control device 13 is required to suppress the amount of current supplied to the fuse 12 so as not to exceed a threshold value. In other words, the control device 13 is required to control the amount of energy so as to suppress the fuse from melting at the time of startup.

[0060] Here, the characteristics of the PTC heater 110 will be described with reference to Fig. 4 to Fig. 6. Fig. 4 is a diagram showing the resistance-temperature characteristics of the PTC heater 110. Fig. 5 is a diagram showing the current-time characteristics of the PTC heater 110. Fig. 6 is a diagram showing the transition of the heat generation temperature and power consumption of the PTC heater 110.

[0061] The PTC heater 110 is a heating element that uses the properties of semiconducting ceramics, mainly composed of barium titanate (BaTiO3), etc. The PTC heater 110 is composed of carbon particles and semiconductor particles.

[0062] As described above, the PTC heater 110 is a positive temperature coefficient heater, and has the characteristic that the resistance value R increases as the temperature T increases. When power is supplied to the PTC heater 110, it starts out with a low resistance value R, and as the temperature T increases, the resistance value R increases.

[0063] When the PTC heater 110 reaches an electrically stable state, the resistance value R rises rapidly, preventing excessive power from being supplied. This allows the PTC heater 110 to function as a self-regulating heat source. The PTC heater 110 retains the control function as a characteristic of the element, and does not require a control function other than that of the element.

[0064] 4, the temperature characteristic of the PTC heater 110 is expressed by an index called the temperature coefficient. The temperature coefficient indicates how much the resistance value R changes when the temperature T rises by 1 degree. In general, the PTC heater 110 has a high temperature coefficient, and has the characteristic that the resistance value R increases rapidly as the temperature T rises.

[0065] The temperature coefficient of the PTC heater 110 is expressed as an exponential function with the resistance value at 25 degrees (R25 shown in FIG. 4) as the reference. In other words, the resistance value R(T) of the PTC heater 110 is expressed as follows.

[0066] R(T) = R25 × exp(B × (T-25))

[0067] B is the temperature coefficient of the PTC heater 110 and T is the temperature of the PTC heater 110 .

[0068] In the temperature characteristics of the PTC heater 110, the Curie temperature (Tc) refers to the temperature at which a sudden increase in resistance value R occurs when the PTC element reaches a certain temperature T. The Curie temperature (Tc) is determined by the physical characteristics of the PTC element. When the temperature T of the PTC heater 110 reaches the Curie temperature (Tc), the resistance value R (T) of the PTC element increases suddenly, so that the PTC element self-regulates to prevent overheating. This characteristic can be used to prevent the electric device 1 from overheating.

[0069] The PTC heater 110 can have any Curie temperature (Tc) set by the material composition.

[0070] Polycrystalline bodies mainly composed of oxides usually become insulating layers due to their high electrical resistance, but they can be made semiconductive by adding additives. Barium titanate, a component of the element of the PTC heater 110, undergoes a phase transition from tetragonal to cubic crystals when it exceeds the Curie temperature (Tc), causing a sudden increase in electrical resistance R, which ultimately acts as a temperature control function.

[0071] As shown in Figures 4, 5, and 6, in the PTC heater 110, the temperature rises due to heat generation, and when the temperature exceeds the Curie temperature (Tc), the resistance value R rises. Therefore, the heat generation is controlled by suppressing the current (inrush current), and as a result, the temperature falls. When the temperature T falls, the resistance value R falls. Therefore, the current I increases, and the heat generation progresses, and this cycle is repeated. Therefore, the PTC heater 110 has self-regulating characteristics.

[0072] Next, the melting characteristics of the fuse 12 and how to judge the fuse 12 will be described.

[0073] The melting characteristics of the fuse 12 are shown in the graph (I 2 Tt) characteristic is used. (I 2 The Tt) characteristic is used when a pulse current, inrush current, etc. flows through the fuse 12.

[0074] Figure 7 shows the 2 Tt) characteristic of (I 2 The formula for calculating Tt is shown in Figure 7. 2 Tt) characteristic of (I 2 To obtain the instantaneous current (Tt), first find the effective value I by integrating the result of squaring the instantaneous current i(t).

[0075] By rearranging the integral formula, (I 2 (I 2 T) is equal to the energy W (J) applied to the resistance R. In other words, (I 2 The Tt) characteristic is the time characteristic of the energy W (J) applied to the minute resistance R of the fuse 12.

[0076] From the above, when the current waveform is complex, such as inrush current I or pulse current I, (I 2 If the energy W(J) applied to the minute resistance R of the fuse 12 is used, it is possible to judge the condition of the fuse 12 without depending on the current waveform.

[0077] Next, the determination of the fuse 12 will be described with reference to Fig. 8. Fig. 8 is a diagram showing a method of determining the fuse 12.

[0078] As shown in the upper graph of Figure 8 (I 2 Consider the case where starting current I (inrush current I) shown in the upper graph of FIG. 8 flows through fuse 12 having a Tt characteristic.

[0079] 8, the horizontal axis represents time and the vertical axis represents Joule integral value. Both the horizontal and vertical axes are expressed in logarithm. The reference Joule integral value indicates the threshold value at which fuse 12 melts.

[0080] The graph shown in the lower part of Fig. 8 shows the change in starting current I. In the graph shown in the lower part of Fig. 8, the horizontal axis represents time t, and the vertical axis represents the current value of starting current I. As shown in the graph in the lower part of Fig. 8, starting current I is divided into section A from time 0 to t1, section B from time t1 to t2, section C from time t2 to t3, and section D from time t3 to t4. To make it easier to understand, the graph in the lower part of Fig. 8 shows the change in starting current I as a straight line.

[0081] (I 2 T) is a Joule integral value, and the integral value of the starting current in sections A, B, C, and D is calculated by the formula shown at the bottom of FIG.

[0082] Based on the integral values ​​of the starting current I in sections A, B, C, and D calculated by the formula shown in the bottom row of Figure 8, the integral value of the starting current I in section A, the integral value of the starting current I in section (A+B), the integral value of the starting current I in section (A+B+C), and the integral value of the starting current I in section (A+B+C+D) are further calculated and plotted on the graph in the top row of Figure 8, to obtain the calculated Joule integral value.

[0083] Next, the current control of the electric device 1 according to this embodiment will be described with reference to FIGS. 9A and 9B.

[0084] Fig. 9A is a diagram showing a change in current value I when power supply is not cut off in a comparative example, and Fig. 9B is a diagram showing a change in current value I when power supply is cut off in electric device 1 according to the present embodiment.

[0085] 9A, if the power supply to the PTC heater 110 is not cut off, the inrush current I supplied at time t5 increases until time t6 after time t01, reaches a peak value, then decreases and stabilizes at a constant current value. However, as described above, it is considered that the calculated Joule integral value will exceed the reference Joule integral value before the relatively long time t01 has elapsed.

[0086] Therefore, the electric device 1 according to this embodiment interrupts the current supply so that the calculated Joule integral value does not exceed the reference Joule integral value.

[0087] The PTC heater 110 of the heat generating unit 11 generates heat upon receiving power supplied from the power supply unit 10, and has temperature characteristics in which the electrical resistance increases as the temperature increases.

[0088] According to this embodiment, when the PTC heater 110 reaches an electrically stable state, the resistance value R rises rapidly. Therefore, excessive power is prevented from being supplied to the PTC heater 110. This allows the PTC heater 110 to function as a self-regulating heat source. The PTC heater 110 retains a control function as a characteristic of the element, and does not require a control function other than that of the element.

[0089] According to this embodiment, it is possible to suppress the number of times that the calculated Joule integral value of fuse 12 exceeds the reference Joule integral value. In other words, it is possible to suppress the calculated Joule integral value from exceeding the reference Joule integral value before the current flowing through heat generating portion 11 reaches its peak, and accordingly, the life of fuse 12 can be extended.

[0090] The current detection unit 130 detects the current value I of the current flowing through the heat generating unit 11 .

[0091] The control unit 133 performs interruption processing when the time during which the current I flows through the heat generating unit 11 and the value based on the current value I reach a preset value.

[0092] According to this embodiment, it is possible to suppress the number of times that the calculated Joule integral value of the fuse 12 exceeds the reference Joule integral value. In other words, it is possible to suppress the calculated Joule integral value from rising above a preset value and exceeding the reference Joule integral value (interrupt threshold). Therefore, it is possible to extend the life of the fuse 12.

[0093] The start-up process includes a restart process for restarting the supply of power to the heat generating unit 11 after the interruption process.

[0094] According to this embodiment, the integration time of the calculated Joule integral can be shortened, and the calculated Joule integral value can be prevented from reaching the reference Joule integral value, as shown in the upper graph of Fig. 8. As a result, the fuse 12 can be prevented from being blown.

[0095] As shown in FIG. 9A, if the power supply is not interrupted, when a startup current I is supplied at time t5, the startup current value increases until time t6, reaches a peak value at time t6, and then decreases.

[0096] Therefore, during time t01 shown in FIG. 9A, the calculated joule value increases, and the calculated joule value shown in the upper graph of FIG. 8 exceeds the reference joule integral value, which may cause fuse 12 to melt.

[0097] 9B, when the control device 13 supplies the startup current I at time t7, the startup current I rises for a period of time t02, but the power supply is interrupted at time t8 (interruption process). After time t03 has elapsed, the control device 13 resumes the supply of the startup current I again at time t9 (resume process).

[0098] The control unit 133 executes the interruption process before the current I flowing through the heat generating unit 11 reaches its peak.

[0099] According to this embodiment, it is possible to reduce the number of times that the calculated Joule integral value of fuse 12 exceeds the reference Joule integral value. In other words, it is possible to prevent the calculated Joule integral value from rising above a preset value and exceeding the reference Joule integral value, thereby extending the life of fuse 12.

[0100] The control unit 133 turns off the supply of startup current I to the fuse 12 and the heat generating unit 11 by the power supply unit 10, and then turns on the supply of startup current I to the fuse 12 and the heat generating unit 11 by the power supply unit 10 again.

[0101] The calculated Joule integral value accumulated up to that point is reset by turning off the supply of startup current I to fuse 12 and heat generating portion 11. When control portion 133 turns off the supply of startup current I to fuse 12 and heat generating portion 11 and then turns it on again, calculation portion 131 starts calculating the calculated Joule integral value anew.

[0102] By controlling in this way, the supply time until the starting current I reaches its peak value is shortened to (time t04), and the Joule integral value (I 2 T) becomes smaller.

[0103] Furthermore, as shown in FIG. 9B, the startup current value supplied to fuse 12 and heat generating portion 11 can reach its peak current value in a short time of time t04, compared to the time t01 it takes to reach the peak current value when the startup current supply to fuse 12 and heat generating portion 11 is continued without being turned off.

[0104] Next, returning to Figs. 1 and 3, the operation of the electric device 1 in this embodiment will be described.

[0105] As shown in FIG. 1, the fan 17 generates an airflow passing through the heat generating portion 11 .

[0106] As shown in FIG. 3, the air blowing control unit 134 controls the fan 17.

[0107] The airflow control unit 134 may reduce the current I supplied to the fan 17 by the power supply unit 10 after the power supply unit 10 turns on the supply of current I to the heat generating unit 11 compared to before the power supply unit 10 turns on the supply of current I to the heat generating unit 11.

[0108] The airflow control unit 134 controls the rotation speed of the fan 17 to a first rotation speed while the control unit 133 is executing the startup process of the heat generating unit 11. The airflow control unit 134 controls the rotation speed of the fan 17 to a second rotation speed that is higher than the first rotation speed after the startup process of the heat generating unit 11 is completed.

[0109] According to this embodiment, by slowing down the rotation of the fan 17 or stopping the fan 17, the temperature of the PTC heater 110 of the heat generating part 11 can be raised to the target temperature in a short time.

[0110] The control device 13 controls the heat generating unit 11, which receives power supplied by the power supply unit 10 and generates heat, and whose electrical resistance increases as the temperature of the heat generating unit 11 increases.

[0111] The control device 13 executes a process of starting the supply of power to the heat generating unit 11, and a process of cutting off the supply of power to the heat generating unit 11 when the current flowing through the heat generating unit 11 is increasing.

[0112] According to this embodiment, damage to the electric device 1 including the fuse 12 can be suppressed.

[0113] Next, a method for controlling the electric device 1 according to this embodiment will be described with reference to FIGS.

[0114] 10 and 11 are flowcharts showing a method for controlling the electric device 1 according to this embodiment.

[0115] The process shown in Fig. 10 includes steps S10 and S11. The process shown in Fig. 11 includes steps S20 to S26.

[0116] The process shown in FIG. 10 is a control method for controlling the supply of power to heat generating portion 11, which receives power, generates heat, and whose electrical resistance decreases as the temperature of heat generating portion 11 increases.

[0117] 10, the power supply unit 10 starts supplying power to the heat generating unit 11 (start step). The process proceeds to step S11.

[0118] In step S11, the control unit 133 cuts off (interrupts) the power supply to the heat generating unit 11 when the current flowing through the heat generating unit 11 is increasing (interruption step), and the process then ends.

[0119] Next, the control in FIG. 10 will be described in more detail with reference to FIG. 11. Step S10 shown in FIG. 10 corresponds to step S20 shown in FIG. 11. In step S20 in FIG. 11, the power supply unit 10 turns on the supply of the startup current (starts the power supply). The process proceeds to step S21.

[0120] In step S21, the current detection unit 130 measures (detects) the current value. The process proceeds to step S22.

[0121] In step S22, the calculation unit 131 calculates the calculated Joule integral value. The process proceeds to step S23.

[0122] In step S23, the control unit 133 determines whether the calculated Joule integral value exceeds the reference Joule integral value. If it exceeds, the process proceeds to step S24. If it does not exceed, the process proceeds to step S26.

[0123] Step S11 shown in Fig. 10 corresponds to step S24 shown in Fig. 11. If the calculated Joule integral value exceeds the reference Joule integral value (Yes in step S23), in step S24, the power supply unit 10 turns off the current supply (interrupts the power supply). The process proceeds to step S25.

[0124] In step S25, the power supply unit 10 turns on the current supply again (resumes the power supply), and the process returns to step S23.

[0125] If the calculated Joule integral value does not exceed the reference Joule integral value (No in step S23), the power supply unit 10 continues the current supply in step S26, and the process then ends.

[0126] The embodiments of the present invention have been described above with reference to the drawings. However, the present invention is not limited to the above embodiments, and can be implemented in various aspects without departing from the gist of the present invention. The drawings may be illustrated mainly in a schematic manner, with each component being the main component, for ease of understanding. The number of each component illustrated may differ from the actual number for the convenience of drawing. In addition, each component illustrated in the above embodiments is an example, and is not particularly limited, and various modifications are possible without substantially departing from the effects of the present invention. [Industrial Applicability]

[0127] INDUSTRIAL APPLICABILITY The present invention can be used in the fields of electric devices and starting methods. [Explanation of symbols]

[0128] 1. Electrical Equipment 2. Air purifier 9 Drive circuit 10 Power supply section 101 Switch 11 Heating part 12. Fuse 13 Control device 130 Current detection section 131 Calculation section 132 Storage section 133 Control Unit 134 Air flow control unit 14 Air Intake 15 Motor 16 Filters 17 Fan 18 Outlet 19 Power Outlets

Claims

1. a heat generating unit that generates heat by receiving power from a power supply unit; a fuse provided in a power supply path between the power supply unit and the heat generating unit; a control unit that controls the power supplied to the heat generating unit through the power supply path; Equipped with The control unit executes a start-up process for the heat generating unit, The startup process includes a start process for starting power supply to the heat generating portion, and an interruption process for interrupting power supply to the heat generating portion.

2. The electrical device according to claim 1 , wherein the heat generating portion has a temperature characteristic in which the electrical resistance increases as the temperature increases.

3. a current detection unit that detects a current value of a current flowing through the heat generating unit, The electric device according to claim 2 , wherein the control unit executes the interruption process when a value based on a time during which the current flows in the heat generating unit and the current value reaches a preset value.

4. The electric device according to claim 1 , wherein the start-up process includes a restart process for restarting the supply of power to the heat generating portion after the interruption process.

5. The electrical device according to claim 1 , wherein the control unit executes the interruption process before a current flowing through the heat generating portion reaches a peak.

6. Further comprising a fan that generates an airflow passing through the heat generating portion, and an airflow control portion that controls the fan, 3. The electrical device of claim 1, wherein the air blowing control unit sets the rotation speed of the fan to a first rotation speed while the control unit is performing the startup process, and sets the rotation speed of the fan to a second rotation speed that is greater than the first rotation speed after the startup process is completed.

7. A method for activating a heat generating unit that generates heat by receiving electric power from a power supply unit, comprising the steps of: A start step of starting the supply of power to the heat generating unit; an interruption step of interrupting the supply of power to the heat generating unit; Including, how to start.

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