hair dryer

Abstract

To provide a hair dryer that suppresses the generation of unpleasant odors when blowing hot air. [Solution] A hair dryer 10 comprising a brushless DC motor 130 having a blower fan 131 housed inside a housing 110, a nichrome wire 143 positioned downstream of the blower fan 131 inside the housing 110, a non-contact temperature sensor 150 positioned near the air outlet 112b1 of the housing 110 to detect the surface temperature of an object, a power switch 111a to switch the power supply to the control unit 160 on and off, and a mode switching button 120 to switch the air supply mode, wherein if the power switch 111a is operated to switch from the off state to the cold air supply state and then to the hot air supply state before air supply starts in the cold air supply state, air will be supplied with the nichrome wire 143 unpowered, and then air will start in the air supply mode used last time.

Description

Technical Field

[0001] The present invention relates to a hair dryer, and more particularly to a hair dryer provided with a non-contact temperature sensor that detects the surface temperature of an object.

Background Art

[0002] Conventionally, there is known a hair dryer that includes a heating element and a non-contact temperature sensor that detects the surface temperature of the user's hair within the air blowing region, and has a scalp drying mode in which power is supplied to the heating element when the detected temperature is lower than a first temperature threshold, and power is not supplied to the heating element when the detected temperature is equal to or higher than the first temperature threshold, and a hair drying mode in which power is supplied to the heating element when the detected temperature is lower than a second temperature threshold that is higher than the first temperature threshold, and power is not supplied to the heating element when the detected temperature is equal to or higher than the second temperature threshold, wherein when the mode button is pressed after the power button is pressed to turn on the power, the scalp drying mode is selected and air blowing starts (for example, refer to Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of Invention

Problems to be Solved by the Invention

[0004] However, in the above-described hair dryer, warm air blowing is started in a state where foreign matters such as dust and hair styling agent are attached to the heating element, so there is a risk that the foreign matters are fused to the heating element by the heat generated by the heating element and become a source of offensive odor.

[0005] Accordingly, the present invention is intended to solve the problems of the prior art as described above, that is, an object of the present invention is to provide a hair dryer that suppresses the generation of offensive odor during warm air blowing. [Means for solving the problem]

[0006] The invention according to claim 1 is a hair dryer comprising: a blower motor having a blower fan housed inside a housing; a heating element disposed downstream of the blower fan inside the housing; a non-contact temperature sensor disposed near the air outlet of the housing for detecting the surface temperature of an object; a control unit electrically connected to the blower motor, the heating element, and the non-contact temperature sensor for controlling the operation of the blower motor and the heating element based on the temperature detected by the non-contact temperature sensor; a power switch electrically connected to the control unit for switching the power supply to the control unit on and off; and a mode switching button electrically connected to the control unit for switching the air supply mode, wherein the power switch has an off state where no power is supplied to the control unit, and a mode switching state where power is supplied to the control unit and the blower motor is powered on and off. The device can switch between a cold air blowing state in which cool air is blown while duty cycle control is performed and the heating element is not constantly energized, and a hot air blowing state in which power is supplied to the control unit and the blowing motor and heating element are duty cycle controlled to blow hot air, and when the power switch is switched from the off state to the hot air blowing state, it passes through the cold air blowing state, and the blowing mode in the hot air blowing state that can be switched by the mode switching button is a scalp drying mode in which the duty cycle is increased to control the heating element when the temperature detected by the non-contact temperature sensor is less than the first threshold temperature and the duty cycle is decreased to control the heating element when the detected temperature is higher than the first threshold temperature and above the second threshold temperature, or when the temperature detected by the non-contact temperature sensor is lower than the third threshold temperature and above the second threshold temperature. ni De This hair drying mode controls the duty cycle of the heating element by increasing the duty cycle ratio, and when the detected temperature is higher than the third threshold temperature (a fourth threshold temperature), it controls the duty cycle of the heating element by decreasing the duty cycle ratio, and by operating the power switch, it switches from the off state to the cold air blowing state via the cold air blowing state. Cool airIf the system switches to the hot air blowing state before the airflow is started, the system will blow air without powering the heating element, and then start blowing air in the blowing mode used in the last time it was used, thereby solving the aforementioned problem.

[0007] The invention according to claim 2 is a hair dryer comprising: a blower motor having a blower fan housed inside a housing; a heating element disposed downstream of the blower fan inside the housing; a non-contact temperature sensor disposed near the air outlet of the housing for detecting the surface temperature of an object; a control unit electrically connected to the blower motor, the heating element, and the non-contact temperature sensor, which performs drive control of the blower motor and heat generation control of the heating element based on the temperature detected by the non-contact temperature sensor; a power button electrically connected to the control unit to switch the power supply to the control unit on and off; and a mode switching button electrically connected to the control unit to switch the blower mode, wherein the power button has an off state where no power is supplied to the control unit, and a state where power is supplied to the control unit to perform duty cycle control of the blower motor and the heating element to deliver warm air. The system can be switched between a warm air blowing state and a non-blending warm air blowing state, and the blowing mode in the warm air blowing state, which can be switched by the mode switching button, is a scalp drying mode in which the duty cycle of the heating element is increased when the temperature detected by the non-contact temperature sensor is below the first threshold temperature and the duty cycle of the heating element is decreased when the detected temperature is above the second threshold temperature which is higher than the first threshold temperature and the duty cycle of the heating element is decreased, or a hair drying mode in which the duty cycle of the heating element is increased when the temperature detected by the non-contact temperature sensor is below the third threshold temperature which is higher than the second threshold temperature and the duty cycle of the heating element is decreased when the detected temperature is above the fourth threshold temperature which is higher than the third threshold temperature and the duty cycle of the heating element is decreased, and when power is supplied to the control unit by operating the power button, the heating element is not powered. Send The aforementioned problem is solved by starting the airflow in scalp drying mode after the initial airflow.

[0008] The invention according to claim 3 further solves the aforementioned problems by adding a non-contact distance sensor, which is positioned near the air outlet of the housing and detects the distance to the object, in addition to the configuration of the hair dryer described in claims 1 and 2, and by changing the rotation speed of the air blower motor based on the distance detected by the non-contact distance sensor in the scalp drying mode or the hair drying mode.

[0009] The invention according to claim 4, in addition to the configuration of the hair dryer described in claim 3, further solves the aforementioned problems by ensuring that the control unit does not always supply power to the heating element when the detection distance by the non-contact distance sensor falls below a predetermined forced cold air distance. [Effects of the Invention]

[0010] According to the hair dryer of the invention of claim 1, a blower motor having a blower fan housed inside a housing, a heating element positioned downstream of the blower fan inside the housing, a non-contact temperature sensor positioned near the air outlet of the housing to detect the surface temperature of an object, a control unit connected to the blower motor, the heating element, and the non-contact temperature sensor to perform drive control of the blower motor and heat generation control of the heating element based on the temperature detected by the non-contact temperature sensor, a power switch electrically connected to the control unit to switch the power supply to the control unit on and off, and a mode switching button electrically connected to the control unit to switch the blower mode, thereby not only providing a wide variety of blower modes, but also achieving the effects unique to the present invention through the following unique configuration of the present invention.

[0011] In other words, according to the hair dryer of the invention described in claim 1, by operating the power switch, the state changes from the off state to the cool air blowing state, and then to the cool air blowing state. Cool airIf the fan is switched to the hot air setting before the fan starts, the fan will run with the heating element unpowered, and then start the fan in the last used fan mode. This removes any foreign matter attached to the heating element by blowing cold air before it is heated by the heating element, thus preventing the fan from running hot air. Airflow It can suppress the generation of unpleasant odors.

[0012] According to the hair dryer of the invention of claim 2, a blower motor having a blower fan housed inside a housing, a heating element positioned downstream of the blower fan inside the housing, a non-contact temperature sensor positioned near the air outlet of the housing to detect the surface temperature of an object, a control unit connected to the blower motor, the heating element, and the non-contact temperature sensor to perform drive control of the blower motor and heat generation control of the heating element based on the temperature detected by the non-contact temperature sensor, a power button electrically connected to the control unit to switch the power supply to the control unit on and off, and a mode switching button electrically connected to the control unit to switch the blower mode, thereby not only providing a wide variety of blower modes, but also achieving the effects unique to the present invention through the following configuration unique to the present invention.

[0013] In other words, according to the hair dryer of the invention described in claim 2, when the power button is pressed and power is supplied to the control unit, after blowing air without supplying power to the heating element, Start the fan in scalp drying mode. As a result, foreign matter adhering to the heating element is removed from the heating element by the blowing of cold air before it is heated by the heating element, thus preventing the use of hot air. Airflow It can suppress the generation of unpleasant odors.

[0014] According to the hair dryer of the invention defined in claim 3, in addition to the effects exhibited by the hair dryer of the invention defined in claim 1 or claim 2, the control unit changes the rotational speed of the blower motor based on the detection distance from the non-contact distance sensor in the scalp drying mode or the hair drying mode, so that the rotational speed of the blower motor is increased when the distance to the target object is long, and the rotational speed of the blower motor can be decreased when the distance to the target object is short, whereby optimal air blowing can be achieved in accordance with the distance between the air outlet of the hair dryer and the target object.

[0015] According to the hair dryer of the invention defined in claim 4, in addition to the effects exhibited by the hair dryer of the invention defined in claim 3, when the detection distance from the non-contact distance sensor becomes less than a predetermined forced cold air distance, the control unit does not always energize the heating element, so that cold air is blown when the distance between the air outlet of the hair dryer and the target object is short, and abnormal overheating of the scalp can be prevented when hot air is blown toward the hair. [Brief Description of the Drawings]

[0016] [Figure 1] A perspective view of a hair dryer that is one embodiment of the present invention. [Figure 2] A perspective view of the hair dryer main body shown in Figure 1. [Figure 3] A left side partial cross-sectional view of the hair dryer main body shown in Figure 1. [Figure 4] A front view of the hair dryer main body shown in Figure 1. [Figure 5] A block diagram for explaining the electrical system of the hair dryer main body shown in Figure 1. [Figure 6] A flowchart for explaining control of the brushless DC motor and the nichrome wire in the care mode. [Figure 7] A flowchart for explaining control of the brushless DC motor and the nichrome wire in the volume mode. [Figure 8] A flowchart for explaining the operation flow of the hair dryer shown in Figure 1. Forms for Carrying Out the Invention

[0017] The present invention relates to a hair dryer comprising: a blower motor having a blower fan housed inside a housing; a heating element disposed downstream of the blower fan inside the housing; a non-contact temperature sensor disposed in the vicinity of a blow port of the housing to detect a surface temperature of an object; a control unit electrically connected to the blower motor, the heating element, and the non-contact temperature sensor, and configured to perform drive control of the blower motor and heat generation control of the heating element based on a temperature detected by the non-contact temperature sensor; a power switch electrically connected to the control unit and configured to switch on and off power supply to the control unit; and a mode switching button electrically connected to the control unit and configured to switch a blowing mode, wherein the power switch is switchable between an off state in which power is not supplied to the control unit, a cold air blowing state in which power is supplied to the control unit to perform duty control on the blower motor and blow cold air without constantly supplying power to the heating element, and a hot air blowing state in which power is supplied to the control unit to perform duty control on the blower motor and the heating element to blow hot air, when the power switch is switched from the off state to the hot air blowing state, the cold air blowing state is passed through, and the blowing mode in the hot air blowing state switched by the mode switching button is a scalp drying mode in which the duty ratio is increased to perform duty control on the heating element when the temperature detected by the non-contact temperature sensor is lower than a first threshold temperature, and the duty ratio is decreased to perform duty control on the heating element when the detected temperature is equal to or higher than a second threshold temperature higher than the first threshold temperature, or a hair drying mode in which the duty ratio is increased to perform duty control on the heating element when the temperature detected by the non-contact temperature sensor is lower than a third threshold temperature higher than the second threshold temperature, and the duty ratio is decreased to perform duty control on the heating element when the detected temperature is equal to or higher than a fourth threshold temperature higher than the third threshold temperature, and by operating the power switch, the off state is passed through to the cold air blowing state, and in the cold air blowing state Cool airAny specific embodiment is acceptable as long as, when the system is switched to a hot air blowing state before the airflow is started, the system blows air without powering the heating element, then starts blowing air in the last used airflow mode, thereby suppressing the generation of an unpleasant odor during hot air blowing. [Examples]

[0018] Hereinafter, a hair dryer 10, which is one embodiment of the present invention, will be described based on Figures 1 to 8.

[0019] <1. Overview of Hair Dryers> First, we will explain the overview of the hair dryer 10 based on Figure 1. Figure 1 is a perspective view of a hair dryer, which is one embodiment of the present invention.

[0020] As shown in Figure 1, the hair dryer 10 comprises a hair dryer body 100 and a nozzle 200 that is detachably attached to the air outlet of the hair dryer body 100. Furthermore, the hair dryer 10 of this embodiment not only blows out cool and warm air, but also has three types of airflow modes for warm air: (1) a care mode (scalp drying mode) that maintains a gentle air temperature for the hair and scalp, protecting the hair and scalp from heat damage and leaving hair shiny; (2) a volume mode (hair drying mode) that uses an appropriate air temperature to thoroughly dry the hair and scalp, lifting the roots of the hair and leaving it voluminous; and (3) a manual mode that blows out warm air at the desired temperature and airflow.

[0021] <2. Hair dryer unit> Next, the hair dryer body 100 will be described based on Figures 2 to 5.

[0022] <2.1. Appearance of the hair dryer body> First, the appearance of the hair dryer body 100 will be described based on Figure 2. Figure 2 is a perspective view of the hair dryer body shown in Figure 1.

[0023] As shown in Figure 2, the hair dryer body 100 has a housing 110 which consists of a handle portion 111 that is held by the user and a cylindrical air blower portion 112 provided at the upper end of the handle portion 111. This housing 110 allows the handle portion 111 to be positioned approximately parallel to the air blower portion 112 by twisting the handle portion 111 relative to the air blower portion 112 while gripping the air blower portion 112.

[0024] <2.1.1. Handle section> The handle portion 111 is provided with a power switch 111a that switches the power supply to the control unit 160 (described later) on and off, and also switches the airflow state. The power switch 111a is a slide switch with three contacts that can move up and down, and can be switched from bottom to top to the following positions: (1) OFF position OP, which is the off state in which no power is supplied to the control unit 160; (2) COLD position CP, which is the cold air blowing state; and (3) HOT position HP, which is the hot air blowing state. In other words, in this embodiment, when switching the power switch 111a from the OFF position OP (off state) to the HOT position HP (hot air blowing state) and when switching the power switch 111a from the HOT position HP to the OFF position OP, the process goes through the COLD position CP (cold air blowing state).

[0025] <2.1.2. Air Blower Section> The air blower unit 112 draws in air from the rear end and expels air from the front end. A filter (not shown) is provided at the rear end of the air blower 112, and a filter cover 113 that protects this filter is detachably attached to the rear end of the air blower 112. This filter cover 113 has numerous air intake ports 113a formed therein.

[0026] Furthermore, a disc-shaped front cover 112b is attached to the front end of the air blower unit 112. In the center of this front cover 112b, there is an air outlet 112b1 for expelling air, and surrounding this air outlet 112b1 are a transmissive window 112b2 that transmits the light emitted from the red LED 186 (described later) and a sensor window 112b3 that transmits the measurement light emitted from the non-contact distance sensor 181 (described later).

[0027] Next, on the left side of the air blower unit 112, as shown in Figure 2, a light-emitting area 112c that illuminates according to the air blowing state, a mode switching button 120 for switching between air blowing modes, an air blowing mode display area 112d for displaying the air blowing mode, a temperature control button 121 for adjusting the air temperature, and an airflow control button 122 for adjusting the airflow volume are provided in that order from front to back.

[0028] The light-emitting region 112c is the region through which the light-emitting element 123, whose color changes according to the detection distance by the non-contact distance sensor 181 (described later) and the wind temperature, is transmitted.

[0029] The mode switching button 120 is only active when the hot air is blowing, and when pressed, it switches the airflow mode in the hot air blowing mode to either care mode or volume mode.

[0030] The fan mode display area 112d is a transparent area that shows the fan mode and schematically displays the airflow and air temperature. It displays the fan mode to the outside, schematically displays the airflow in three stages, and schematically displays the air temperature in three stages.

[0031] The temperature control button 121 is also only effective when hot air is being blown. When pressed while hot air is being blown in care mode or volume mode, it switches the blowing mode to manual mode. Furthermore, when the device is blowing warm air in manual mode, pressing the temperature control button 121 will sequentially change the air temperature in three stages (low temperature → medium temperature → high temperature → low temperature...).

[0032] When the airflow adjustment button 122 is pressed while cool air is being blown, it sequentially changes the airflow in three stages (low → medium → high → low...). Then, when warm air is being blown in care mode or volume mode, pressing the airflow adjustment button 122 switches the airflow mode to manual mode. When the fan speed adjustment button 122 is pressed while the unit is blowing warm air in manual mode, the fan speed will change sequentially in three stages (low → medium → high → low...).

[0033] <2.2. Internal structure of the hair dryer body> Next, the internal structure of the hair dryer body will be explained based on Figures 3 and 4. Figure 3 is a cross-sectional view of the left side of the hair dryer body shown in Figure 1, and Figure 4 is a front view of the hair dryer body shown in Figure 1.

[0034] As shown in Figure 3, a brushless DC motor (blower motor) 130 is built into the rear end of the air blower unit 112. The brushless DC motor 130 housed inside the housing 110 has a blower fan 131. Therefore, when the brushless DC motor 130 is energized, the blower fan 131 rotates, drawing air in through the intake port 113a and supplying it into the blower unit 112.

[0035] As shown in Figure 3, a far-infrared generating unit 140 is positioned at the front end of the air blower section 112 (i.e., downstream of the blower fan 131). The far-infrared generating unit 140, located inside the housing 110, comprises a mica cylindrical body 141, a mica rectangular plate 142 enclosed within the cylindrical body 141 and extending in the front-to-back direction, and a nichrome wire (heating element) 143 wound around the rectangular plate 142. Therefore, when the nichrome wire 143 is heated, the cylindrical body 141 and the rectangular plate body 142 are heated, and far-infrared rays are emitted from the cylindrical body 141 and the rectangular plate body 142.

[0036] Furthermore, a non-contact temperature sensor 150 is provided near the center of the far-infrared generating unit 140 when viewed from the front. A non-contact temperature sensor 150, positioned near the air outlet 112b1 of the housing 110, detects the surface temperature of the object (e.g., hair or scalp).

[0037] A control board 161 of the control unit 160 is installed between the brushless DC motor 130 and the far-infrared generating unit 140. This control board 161 is equipped with a microcontroller (not shown).

[0038] A needle-shaped ion generating electrode 170 (a positive ion generating electrode 171 located above and a negative ion generating electrode 172 located below) is provided in front of the cylindrical body 141 of the far-infrared generating unit 140 and between it and the front cover 112b.

[0039] Furthermore, an annular substrate 180 is provided at the front end of the air blower 112 and inside the front cover 112b. As shown in Figure 4, a non-contact distance sensor 181 is provided near the upper end of this annular substrate 180. A non-contact distance sensor 181, positioned near the air outlet 112b1 of the housing 110, detects the distance to the object.

[0040] Furthermore, the annular substrate 180 is equipped with three Hall sensors for detecting the south pole (first south pole detecting Hall sensor 182, second south pole detecting Hall sensor 183, and third south pole detecting Hall sensor 184) and one Hall sensor for detecting the north pole (north pole detecting Hall sensor 185). Since the Hall sensor that detects this magnetic field is located on the annular substrate 180, it is positioned near the air outlet 112b1 of the housing 110. Furthermore, multiple red LEDs 186 that emit light with a wavelength of 630-660 nm are arranged on this annular substrate 180.

[0041] <2.3. Electrical System of the Hair Dryer> Next, the electrical system of the hair dryer body 100 configured in this way will be explained based on Figure 5. Figure 5 is a block diagram illustrating the electrical system of the hair dryer shown in Figure 1.

[0042] As shown in Figure 5, the control unit 160 is electrically connected to at least the following: a power switch 111a, a mode switching button 120, a temperature adjustment button 121, an airflow adjustment button 122, a light-emitting element 123, an airflow status display unit 124, a brushless DC motor 130, a nichrome wire 143, a non-contact temperature sensor 150, a positive ion generating electrode 171, a negative ion generating electrode 172, a non-contact distance sensor 181, a first south pole detection Hall sensor 182, a second south pole detection Hall sensor 183, a third south pole detection Hall sensor 184, a north pole detection Hall sensor 185, and a red LED 186.

[0043] The control unit 160 receives signals from the mode switching button 120, the temperature control button 121, and the airflow control button 122. Furthermore, the control unit 160 receives detection results from the non-contact temperature sensor 150 and the non-contact distance sensor 181, as well as detection results from the first S-pole detection Hall sensor 182, the second S-pole detection Hall sensor 183, the third S-pole detection Hall sensor 184, and the N-pole detection Hall sensor 185.

[0044] The microcontroller in the control unit 160 operates the light-emitting element 123, the airflow status display unit 124, the brushless DC motor 130, the nichrome wire 143, the positive ion generating electrode 171, the negative ion generating electrode 172, and the red LED 186. Furthermore, the drive control of the brushless DC motor 130 by the microcontroller of the control unit 160 is a type of PWM (Pulse Width Modulation) control, which is duty cycle control (control that changes the ratio of ON (high level) time and OFF (low level) time in one cycle of the signal) that changes the average voltage by adjusting the proportion of ON time (duty cycle) in the ON / OFF period (pulse) of the electrical signal. Furthermore, the heat generation control of the nichrome wire 143 by the microcontroller in the control unit 160 is also performed using duty cycle control.

[0045] <3. Airflow patterns using a hair dryer> Next, we will explain the airflow pattern produced by the hair dryer 10 configured in this way.

[0046] <3.1. Cool air blowing state> First, let's describe the cold air blowing state when the power switch 111a is in the COLD position CP.

[0047] The cold air blowing state is a blowing state in which power is supplied to the control unit 160 to control the duty cycle of the brushless DC motor 130, while power is not constantly supplied to the nichrome wire 143. Furthermore, when the unit is in cool air blowing mode, the airflow can be adjusted in three stages by pressing the airflow adjustment button 122.

[0048] In addition, when blowing cold air, feedback control of the brushless DC motor 130 based on the temperature detected by the non-contact temperature sensor 150 and the distance detected by the non-contact distance sensor 181 is not performed. Then, only the negative ion generating electrode 172 operates, and the positive ion generating electrode 171 does not operate. Additionally, the red LED 186 remains illuminated while the unit is blowing cold air.

[0049] <3.2. Hot air blowing state> Next, we will explain the hot air blowing state when the power switch 111a is in the HOT position (HP). The hot air blowing state is a blowing state in which power is supplied to the control unit 160 to perform duty cycle control on the brushless DC motor 130 and the nichrome wire 143. In this embodiment, as described above, there are three blowing modes: (1) manual mode, (2) care mode (scalp drying mode), and (3) volume mode (hair drying mode). The following describes each fan mode.

[0050] <3.2.1. Manual Mode> In manual mode with warm air blowing enabled, the air temperature can be adjusted in three stages by pressing the temperature control button 121, and the airflow can be adjusted in three stages by pressing the airflow control button 122. In other words, in manual mode with hot air blowing enabled, nine different airflow patterns can be selected.

[0051] In manual mode, the drive control of the brushless DC motor 130 is not performed based on the temperature detected by the non-contact temperature sensor 150 or the distance detected by the non-contact distance sensor 181. Then, only the negative ion generating electrode 172 operates, and the positive ion generating electrode 171 does not operate. Additionally, the red LED 186 remains illuminated while in manual mode.

[0052] <3.2.2. Care Mode> In the care mode, which is set to blow hot air, the drive control of the brushless DC motor 130 and the heat generation control of the nichrome wire 143 are performed based on the temperature detected by the non-contact temperature sensor 150 and the distance detected by the non-contact distance sensor 181. Specifically, the procedure is as shown in Figure 6.

[0053] (Step S1) First, the control unit 160 determines the output (detection distance) from the non-contact distance sensor 181. For example, if the detection distance is 0 cm or more but less than 5 cm, proceed to step S2-1; if the detection distance is greater than 10 cm, proceed to step S2-2; and if the detection distance is 5 cm or more but less than 10 cm, proceed to step S2-3.

[0054] (Step S2-1) In step S2-1, because the distance between the hair dryer 10 and the object is too close, the control unit 160 does not constantly supply power to the nichrome wire 143, but instead supplies power only to the brushless DC motor 130, causing the blower fan 131 to rotate at a predetermined forced-cool air rotation speed to forcibly blow cool air, and then returns to step S1.

[0055] (Step S2-2) In step S2-2, the control unit 160 sets the rotation speed of the brushless DC motor 130 to the maximum rotation speed in care mode and proceeds to step S3.

[0056] (Step S3) In step S3, the control unit 160 sets a predetermined duty cycle according to the distance detected by the non-contact distance sensor 181, and proceeds to step S4.

[0057] (Step S4) In step S4, based on the settings from steps S2-2 and S3, warm air is blown in, and the process returns to step S1.

[0058] (Step S2-3) In step S2-3, the control unit 160 sets a predetermined rotation speed for the brushless DC motor 130 according to the distance detected by the non-contact distance sensor 181, and then proceeds to step S5.

[0059] (Step S5) In step S5, the control unit 160 sets the duty cycle range (upper and lower limits of the duty cycle) according to the distance detected by the non-contact distance sensor 181, and proceeds to step S6.

[0060] (Step S6) In step S6, the control unit 160 determines the output (detected temperature) from the non-contact temperature sensor 150. For example, if the detected temperature is less than 45°C, proceed to step S7-1; if the detected temperature is 65°C or higher, proceed to step S7-2; and if the detected temperature is within the target temperature range (e.g., 55°C ± 10°C), return to step S1.

[0061] (Step S7-1) In step S7-1, the duty cycle is increased by a predetermined amount from the current duty cycle to reach the upper limit duty cycle (first upper limit duty cycle) defined in step S5. The increase in this duty cycle may be achieved in a single increase to reach the first upper limit duty cycle, or it may be achieved in multiple increases.

[0062] (Step S7-2) In step S7-2, the duty cycle is reduced by a predetermined amount from the current duty cycle so that it reaches the lower limit duty cycle (first lower limit duty cycle) determined in step S5. The amount of decrease in this duty cycle may be such that it reaches the first lower limit duty cycle in a single increase, or it may be such that it reaches the first lower limit duty cycle in multiple decreases.

[0063] As described above, the care mode not only changes the rotation speed of the brushless DC motor 130 based on the distance detected by the non-contact distance sensor 181, but also increases the duty cycle to control the nichrome wire 143 when the temperature detected by the non-contact temperature sensor 150 is below a first threshold temperature (e.g., 45°C), and decreases the duty cycle to control the nichrome wire 143 when the detected temperature is above a second threshold temperature (e.g., 65°C) which is higher than the first threshold temperature. Furthermore, in care mode, if the detection distance by the non-contact distance sensor 181 falls below a predetermined forced cooling distance (e.g., 5 cm), the control unit 160 will not always supply power to the nichrome wire 143.

[0064] In care mode, only the negative ion generating electrode 172 operates, while the positive ion generating electrode 171 does not. Additionally, the red LED 186 remains illuminated throughout the care mode.

[0065] <3.2.3. Volume Mode> Even in volume mode with hot air blowing, the drive control of the brushless DC motor 130 and the heat generation control of the nichrome wire 143 are performed based on the temperature detected by the non-contact temperature sensor 150 and the distance detected by the non-contact distance sensor 181. Specifically, the procedure is as shown in Figure 7.

[0066] Since the drive control of the brushless DC motor 130 and the heat generation control of the nichrome wire 143 in volume mode are almost the same as those in care mode, the same step numbers are simply assigned. The following are the changes in the drive control of the brushless DC motor 130 and the heat generation control of the nichrome wire 143 in volume mode compared to care mode.

[0067] [1] Step S2-2 The control unit 160 sets the rotation speed of the brushless DC motor 130 to the maximum rotation speed in volume mode. [2] Step S3 The predetermined duty cycle, which is set according to the distance detected by the non-contact distance sensor 181, is greater than that of the care mode. [3] Step S2-3 The predetermined rotational speed of the brushless DC motor 130, which is set according to the distance detected by the non-contact distance sensor 181, is greater than that of the care mode. [4] Step S5 The duty cycle range (upper and lower limits of the duty cycle) set according to the detection distance by the non-contact distance sensor 181 is larger than that of the care mode. Specifically, as an example, the duty cycle range in care mode with a detection distance of 7 cm is 26%-42%, and the duty cycle range in volume mode with a detection distance of 7 cm is 56%-79%. [5] Step S6 In volume mode, if the detected temperature is less than 65°C, the process proceeds to step S7-1; if the detected temperature is 85°C or higher, the process proceeds to step S7-2; and if the detected temperature is within the target temperature range (e.g., 75°C ± 10°C), the process returns to step S1.

[0068] As described above, the volume mode not only changes the rotation speed of the brushless DC motor 130 based on the distance detected by the non-contact distance sensor 181, but also controls the duty cycle of the nichrome wire 143 by increasing the duty cycle when the temperature detected by the non-contact temperature sensor 150 is below the third threshold temperature (e.g., 65°C), and by decreasing the duty cycle of the nichrome wire 143 when the detected temperature is above the fourth threshold temperature (e.g., 85°C), which is higher than the third threshold temperature. Furthermore, even in volume mode, if the detection distance by the non-contact distance sensor 181 falls below a predetermined forced cooling distance (for example, 5 cm), the control unit 160 will not always supply power to the nichrome wire 143.

[0069] In volume mode, the negative ion generating electrode 172 and the positive ion generating electrode 171 are activated. Additionally, the red LED 186 remains illuminated while in volume mode.

[0070] <4. Hair dryer operation flow> Next, based on Figure 8, the operation flow of the hair dryer 10 configured as described above will be explained. Figure 8 is a flowchart illustrating the operation flow of the hair dryer shown in Figure 1.

[0071] When the power switch 111a is slid upward from the OFF position OP to the COLD position CP, the system switches to a cold air blowing state and cold air is blown out from the air outlet 112b1.

[0072] When the power switch 111a is slid further upward from the COLD position CP to the HOT position HP, the system switches to a hot air blowing state and hot air is blown out from the air outlet 112b1. The following provides a detailed explanation of the operation when hot air is being blown.

[0073] (Step S10) First, the control unit 160 determines whether it is the first time the system is being started. If the control unit 160 determines that it is the first startup, the process proceeds to step S11. If the control unit 160 determines that it is not the first startup but a second or subsequent startup, the process proceeds to step S12.

[0074] (Step S11) If the control unit 160 determines that it is the first startup, it starts blowing air in an initial mode with a high temperature and a medium airflow. After that, the process proceeds to parallel processing S14.

[0075] (Step S12) If the control unit 160 determines that this is the second or subsequent startup, it will blow air without energizing the nichrome wire 143 for a delay time (for example, 0.6 seconds) that is short enough that the human body does not perceive it as cold air, and then proceed to step S13.

[0076] (Step S13) In step S13, the fan starts using the same fan mode as when the previous use ended. After that, the process proceeds to parallel processing S14.

[0077] (Parallel processing S14) Next, the control unit 160 performs the following operations in parallel: an operation based on the mode switching signal from the mode switching button 120 (step S110), an operation based on the air temperature adjustment signal from the temperature adjustment button 121 (step S120), and an operation based on the air volume adjustment signal from the air volume adjustment button 122 (step S130).

[0078] <4.1. Operation based on mode switching signal (step S110)> (Step S111) As part of the operation based on the mode switching signal from the mode switching button 120, the control unit 160 first determines whether or not the mode switching button 120 has been pressed (i.e., whether or not a mode switching signal has been input to the control unit 160). If the control unit 160 determines that the mode switching button 120 has been pressed, the process proceeds to step S112. If the control unit 160 determines that the mode switching button 120 has not been pressed, the process returns to step S111 and continues to determine whether or not the mode switching button 120 has been pressed.

[0079] (Step S112) Next, the control unit 160 determines whether the current blowing mode is care mode. If the current blowing mode is care mode, the control unit 160 blows air for a predetermined delay time without energizing the nichrome wire 143, similar to step S12, then executes volume mode and exits parallel processing S14. If the current blowing mode is not care mode, the control unit 160 blows air for a predetermined delay time without energizing the nichrome wire 143, as in step S12, then executes care mode and exits parallel processing S14.

[0080] <4.2. Operation based on air temperature control signal (step S120)> (Step S121) As part of the operation based on the air temperature adjustment signal from the temperature adjustment button 121, the control unit 160 first determines whether or not the temperature adjustment button 121 has been pressed (i.e., whether or not the air temperature adjustment signal has been input to the control unit 160). If the control unit 160 determines that the temperature control button 121 has been pressed, the process proceeds to step S122. If the control unit 160 determines that the temperature control button 121 has not been pressed, the process returns to step S121 and continues to determine whether or not the temperature control button 121 has been pressed.

[0081] (Steps S122, S123) Next, the control unit 160 determines whether the current fan mode is manual mode or not. If the current fan mode is manual mode, proceed to step S123, and the control unit 160 changes the fan temperature. If the current fan mode is not manual mode, the control unit 160 switches to manual mode and exits parallel processing S14.

[0082] <4.3. Operation based on airflow control signal (Step S130)> (Step S131) As part of the operation based on the airflow adjustment signal from the airflow adjustment button 122, the control unit 160 first determines whether or not the airflow adjustment button 122 has been pressed (i.e., whether or not an airflow adjustment signal has been input to the control unit 160). If the control unit 160 determines that the airflow adjustment button 122 has been pressed, the process proceeds to step S132. If the control unit 160 determines that the airflow adjustment button 122 has not been pressed, the process returns to step S131 and continues to determine whether or not the airflow adjustment button 122 has been pressed.

[0083] (Steps S132, S133) Next, the control unit 160 determines whether the current fan mode is manual mode or not. If the current fan mode is manual mode, proceed to step S133, and the control unit 160 changes the airflow. If the current fan mode is not manual mode, the control unit 160 switches to manual mode and exits parallel processing S14.

[0084] <4.4. Termination Determination> (Step S15) If parallel processing S14 is completed, the control unit 160 determines whether the power switch 111a is in the HOT position HP. If the control unit 160 determines that the power switch 111a is in the HOT position HP, the process returns to parallel processing S14. If the control unit 160 determines that the power switch 111a is not in the HOT position HP, the process proceeds to step S16.

[0085] (Step S16) The control unit 160 stores the airflow mode in a memory located on the control board 161. Subsequently, the control unit 160 sets the device to a cold air blowing state if the power switch 111a is in the COLD position CP, and to a OFF state if the power switch 111a is in the OFF position OP.

[0086] <4.5. Summary> According to the operation flow described above, in the hair dryer 10 of this embodiment, even if the power switch 111a is operated to switch from the off state to the cold air blowing state, and then to the hot air blowing state before airflow starts in the cold air blowing state, airflow will be started in the last used airflow mode after airflow has been supplied without energizing the nichrome wire 143.

[0087] Furthermore, in the usage environment of the hair dryer 10, there are many instances when dust and other debris can enter the inside of the hair dryer body 100. Therefore, in the hair dryer 10 of this embodiment, not only when switching from the off state to the hot air blowing state via the cold air blowing state by operating the power switch 111a, but also when blowing air in the hot air blowing state before starting the care mode and volume mode, the nichrome wire 143 is not energized when blowing air.

[0088] <5. Effects of using a hair dryer 10> According to the hair dryer 10 of this embodiment described above, when the power switch 111a is operated to switch from the off state to the cold air blowing state, and then to the hot air blowing state before the cold air blowing state is started, the nichrome wire 143, which is the heating element, is not energized when the air is blown, and then the air is started in the last used air blowing mode. As a result, any foreign matter attached to the heating element is removed from the heating element by the blowing of cold air before it is heated by the heating element, thus suppressing the generation of an unpleasant odor when hot air is blown.

[0089] Furthermore, in the care mode, which is the scalp drying mode, or the volume mode, which is the hair drying mode, the control unit 160 changes the rotation speed of the brushless DC motor 130, which is the blower motor, based on the distance detected by the non-contact distance sensor 181. This makes it possible to increase the rotation speed of the brushless DC motor 130 when the distance to the object is far, and decrease the rotation speed of the brushless DC motor 130 when the distance to the object is close, thereby achieving optimal airflow according to the distance between the air outlet 112b1 of the hair dryer 10 and the object.

[0090] Furthermore, when the detection distance by the non-contact distance sensor 181 falls below a predetermined distance, the control unit 160 does not continuously supply power to the nichrome wire 143. As a result, when the distance between the air outlet 112b1 of the hair dryer 10 and the object is short, cool air is blown out, thus preventing abnormal overheating of the scalp when blowing hot air towards the hair.

[0091] <Variation> Although an embodiment of the present invention, the hair dryer 10, has been described above, the present invention is not limited to the hair dryer 10 of the above-described embodiment.

[0092] For example, the power switch 111a of the hair dryer 10 in the above-described embodiment could switch between a cool air blowing state and a hot air blowing state in addition to switching the power supply to the control unit 160 on and off. However, instead of a power switch, a power button that only switches the power supply to the control unit 160 on and off may be provided, and the cool air blowing state may be achieved by pressing a dedicated button. In this case, the power button can be freely switched between the off state and the hot air blowing state. Even with a hair dryer that has a power switch that only switches the power on and off to such a control unit, when power is turned on to the control unit by pressing the power button, if air is blown without power being supplied to the heating element, and then air is blown in scalp drying mode, foreign matter attached to the heating element is removed by the blown air before it is heated by the heating element, thus suppressing the generation of unpleasant odors when hot air is blown.

[0093] Furthermore, while the hair dryer 10 in the above-described embodiment and the modified hair dryer used duty cycle control for the blower fan and nichrome wire, other control methods such as on / off control or proportional control may be used instead of duty cycle control. In other words, the care mode (scalp drying mode) may be configured such that the nichrome wire is always energized when the temperature detected by the non-contact temperature sensor is below the first threshold temperature, and the nichrome wire is never energized when the detected temperature is above the second threshold temperature (higher than the first threshold temperature), and the volume mode (hair drying mode) may be configured such that the nichrome wire is always energized when the temperature detected by the non-contact temperature sensor is below the third threshold temperature (higher than the second threshold temperature), and the nichrome wire is never energized when the detected temperature is above the fourth threshold temperature (higher than the third threshold temperature). [Explanation of Symbols]

[0094] 10. Hair dryer 100 ··· Hair dryer body 110 ··· Housing 111... Handle section 111a ··· Power switch 112 ··· Blower section 112b ··· Front cover 112b1 ··· Air outlet 112b2 ··· Transparent window 112b3 ··· Sensor window 112c ··· Luminous region 112d ··· Fan mode display area 113... Filter cover 113a ··· Inlet 120... Mode switching button 121 ··· Temperature control button 122 ··· Fan speed adjustment button 123 ··· Luminous body 124 ··· Fan status display unit 130 ··· Brushless DC motor (blower motor) 131 ··· Blower fan 140 ··· Far-infrared generating unit 141 ··· Cylindrical body 142 ... rectangular plate 143... Nichrome wire (heating element) 150 ··· Non-contact temperature sensor 160 ··· Control Unit 161... Control board 170 ··· Ion generating electrode 171 ··· Positive ion generating electrode 172 ··· Negative ion generating electrode 180 ··· Ring-shaped substrate 181 ··· Non-contact distance sensor 182... First S-pole detection Hall sensor (Hall sensor) 183... Second S-pole detection Hall sensor (Hall sensor) 184... Third S-pole detection Hall sensor (Hall sensor) 185 ··· North pole detection Hall sensor (Hall sensor) 186 ··· Red LED 200... Nozzle OP...OFF position CP...COLD position HP...HOT position

Claims

1. A hair dryer comprising: a blower motor having a blower fan housed inside a housing; a heating element positioned downstream of the blower fan inside the housing; a non-contact temperature sensor positioned near the air outlet of the housing for detecting the surface temperature of an object; a control unit electrically connected to the blower motor, the heating element, and the non-contact temperature sensor for controlling the drive of the blower motor and the heating element's heat generation based on the temperature detected by the non-contact temperature sensor; a power switch electrically connected to the control unit for switching the power supply to the control unit on and off; and a mode switching button electrically connected to the control unit for switching the blower mode, wherein The power switch is switchable between an off state in which no power is supplied to the control unit, a cold air supply state in which power is supplied to the control unit and the blower motor is duty-shifted while cold air is supplied without supplying power to the heating element, and a hot air supply state in which power is supplied to the control unit and the blower motor and the heating element are duty-shifted to supply hot air. When switching the power switch from the off state to the hot air blowing state, it passes through the cold air blowing state, The airflow mode in the hot air blowing state, which can be switched by the mode switching button, is a scalp drying mode in which the duty cycle of the heating element is increased when the temperature detected by the non-contact temperature sensor is less than a first threshold temperature, and the duty cycle of the heating element is decreased when the detected temperature is higher than or equal to a second threshold temperature which is higher than the first threshold temperature, or a hair drying mode in which the duty cycle of the heating element is increased when the temperature detected by the non-contact temperature sensor is less than a third threshold temperature which is higher than the second threshold temperature, and the duty cycle of the heating element is decreased when the detected temperature is higher than or equal to a fourth threshold temperature which is higher than the third threshold temperature. A hair dryer characterized in that, when the power switch is operated to switch from the off state to the cold air blowing state, and then to the hot air blowing state before the cold air blowing starts in the cold air blowing state, the hair dryer blows air without powering the heating element, and then starts blowing air in the blowing mode used last time.

2. A hair dryer comprising: a blower motor having a blower fan housed inside a housing; a heating element positioned downstream of the blower fan inside the housing; a non-contact temperature sensor positioned near the air outlet of the housing to detect the surface temperature of an object; a control unit electrically connected to the blower motor, the heating element, and the non-contact temperature sensor to perform drive control of the blower motor and heat control of the heating element based on the temperature detected by the non-contact temperature sensor; a power button electrically connected to the control unit to switch the power supply to the control unit on and off; and a mode switching button electrically connected to the control unit to switch the blower mode, wherein The power button can be switched between an off state, where no power is supplied to the control unit, and a hot air supply state, where power is supplied to the control unit and the blower motor and heating element are duty-cycle controlled to blow hot air. The airflow mode in the hot air blowing state, which can be switched by the mode switching button, is a scalp drying mode in which the duty cycle of the heating element is increased when the temperature detected by the non-contact temperature sensor is less than a first threshold temperature, and the duty cycle of the heating element is decreased when the detected temperature is higher than or equal to a second threshold temperature which is higher than the first threshold temperature, or a hair drying mode in which the duty cycle of the heating element is increased when the temperature detected by the non-contact temperature sensor is less than a third threshold temperature which is higher than the second threshold temperature, and the duty cycle of the heating element is decreased when the detected temperature is higher than or equal to a fourth threshold temperature which is higher than the third threshold temperature. A hair dryer characterized in that, when power is supplied to the control unit by operating the power button, it first blows air without supplying power to the heating element, and then starts blowing air in scalp drying mode.

3. The housing is equipped with a non-contact distance sensor positioned near the air outlet to detect the distance to the object, The hair dryer according to claim 1 or 2, characterized in that the control unit changes the rotation speed of the blower motor based on the distance detected by the non-contact distance sensor in the scalp drying mode or the hair drying mode.

4. The hair dryer according to claim 3, characterized in that the control unit does not always supply power to the heating element when the detection distance by the non-contact distance sensor falls below a predetermined forced cold air distance.

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