CN114945307A

CN114945307A - Hand drying device

Info

Publication number: CN114945307A
Application number: CN202080090468.8A
Authority: CN
Inventors: 福田勇辉; 藤村达也
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2020-01-27
Filing date: 2020-01-27
Publication date: 2022-08-26
Anticipated expiration: 2040-01-27
Also published as: CN114945307B; JP7186904B2; JPWO2021152656A1; WO2021152656A1

Abstract

The invention provides a hand drying device, which can detect the existence of hands and the existence of water in a wash basin by using a sensor, thereby inhibiting the increase of cost. A hand drying device (100) is provided with: a nozzle (3) that blows an air flow toward a drying processing space (50) in which an opponent is dried; a blower (2) that generates an air flow; a capacitance sensor (4) which is provided with two electrodes and detects the capacitance between the two electrodes; a detection unit (41) that detects that water is present in the wash basin (410) receiving the airflow when the capacitance detected by the capacitance sensor (4) is equal to or greater than a first water detection threshold value, and that detects that a hand is present in the drying processing space (50) when the capacitance detected by the capacitance sensor (4) is equal to or less than a first hand detection threshold value that is less than the first water detection threshold value; and an operation control unit (42) that controls the operation of the blower (2) on the basis of the detection result of the detection unit (41).

Description

Hand drying device

Technical Field

The present disclosure relates to a hand drying device that dries wet hands.

Background

In order to keep the hands in a sanitary state, it is necessary to sanitarily dry the washed hands. Therefore, a hand drying device that dries hands by spraying a high-speed air flow to the hands and blowing off water adhering to the hands is used, instead of wiping the washed wet hands with a towel or handkerchief.

As a conventional hand dryer, there is known a washing-and-washing integrated hand dryer including: a wash basin having a space for accumulating water; an air nozzle which blows high-speed air into the sink; a blower that generates high-speed wind; a hand detection sensor that detects the presence or absence of a hand; and a capacitance sensor that detects water accumulated in the sink by capacitance, and prevents the water accumulated in the sink from scattering by preventing the drive power from being supplied to the air blower even if the hand detection sensor detects a hand when the water accumulated in the sink is detected by the capacitance sensor (see, for example, patent document 1).

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2014-50473

Disclosure of Invention

Problems to be solved by the invention

However, in the hand drying device, since the electrostatic capacity sensor for detecting that water is accumulated in the sink is provided separately from the hand detection sensor, there is a problem that the cost increases.

The present disclosure has been made to solve the above-described problems, and an object of the present disclosure is to provide a hand drying device capable of suppressing an increase in cost by detecting the presence or absence of a hand and the presence or absence of water in a sink with one sensor.

Means for solving the problems

The hand drying device of the present disclosure includes: a nozzle that blows an air flow toward a drying processing space where a hand is dried; a blower that generates an air flow; an electrostatic capacitance sensor that includes two electrodes and detects an electrostatic capacitance between the two electrodes; a detection unit that detects that water is present in the sink that receives the air flow when the capacitance detected by the capacitance sensor is equal to or greater than a first water detection threshold value, and that detects that a hand is present in the drying processing space when the capacitance detected by the capacitance sensor is equal to or less than a first hand detection threshold value that is smaller than the first water detection threshold value; and an operation control unit that controls the operation of the blower based on a detection result of the detection unit.

Further, the hand drying device of the present disclosure includes: a nozzle that blows an air flow toward a drying processing space where a hand is dried; a blower that generates an air flow; an infrared sensor that includes an infrared light emitting element that emits infrared light and an infrared light receiving element that receives infrared light, and that detects the amount of infrared light received by the infrared light receiving element; a detection unit that detects that water is present in the sink receiving the air flow when the amount of light received by the infrared sensor is equal to or less than a third water detection threshold, and that detects that a hand is present in the drying processing space when the amount of light received by the infrared sensor is equal to or more than a third hand detection threshold that is greater than the third water detection threshold; and an operation control unit that controls the operation of the blower based on a detection result of the detection unit.

Effects of the invention

According to the hand drying device of the present disclosure, since it is possible to detect whether there is a hand in the drying processing space or water in the sink with one sensor, it is possible to suppress an increase in cost.

Drawings

Fig. 1 is a top view of a commode including a hand dryer according to embodiment 1.

Fig. 2 is a sectional view of a commode provided with the hand dryer of embodiment 1, and is a sectional view showing a section a-a in fig. 1.

Fig. 3 is a sectional view of a commode provided with the hand dryer of embodiment 1, and is a sectional view showing a section B-B of fig. 1.

Fig. 4 is a sectional view of a commode including the hand dryer of embodiment 1, and is a sectional view showing a section C-C of fig. 1.

Fig. 5 is a schematic diagram illustrating the principle of the electrostatic capacity sensor of the hand drying device according to embodiment 1, and is a diagram showing a state where a hand is not in proximity to the electrostatic capacity sensor.

Fig. 6 is a schematic diagram for explaining the principle of the electrostatic capacity sensor of the hand drying device according to embodiment 1, and is a diagram showing a state when a hand approaches the electrostatic capacity sensor.

Fig. 7 is a block diagram showing a configuration of a control system of the hand dryer according to embodiment 1.

Fig. 8 is a diagram showing an example of a hardware configuration of a processing circuit according to embodiment 1.

Fig. 9 is a flowchart showing the operation of the control unit according to embodiment 1.

Fig. 10 is a timing chart showing changes in capacitance detected by the capacitance sensor of the hand dryer according to embodiment 1.

Fig. 11 is a sectional view of a commode provided with a hand dryer according to a modification of embodiment 1, and is a sectional view showing a section C-C of fig. 1.

Fig. 12 is a sectional view of a commode provided with a hand dryer according to a modification of embodiment 1, and is a sectional view showing a section C-C of fig. 1.

Fig. 13 is a sectional view of a commode provided with a hand dryer according to a modification of embodiment 1, and is a sectional view showing a section C-C of fig. 1.

Fig. 14 is a sectional view of a commode provided with a hand dryer according to a modification of embodiment 1, and is a sectional view showing a section C-C of fig. 1.

Fig. 15 is a flowchart showing the operation of the control unit according to embodiment 2.

Fig. 16 is a flowchart showing the operation of the control unit according to embodiment 3.

Fig. 17 is a view of the commode provided with the hand drying device according to embodiment 4, as viewed from above.

Fig. 18 is a sectional view of a sink provided with the hand dryer of embodiment 4, and is a sectional view showing a section C-C in fig. 17.

Fig. 19 is a sectional view of a commode provided with the hand drying device according to embodiment 5, which corresponds to the section C-C in fig. 1.

Fig. 20 is a flowchart showing the operation of the control unit according to embodiment 5.

Fig. 21 is a timing chart showing changes in the amount of infrared light detected by the infrared sensor of the hand dryer according to embodiment 5.

Detailed Description

Embodiment 1.

The configuration of the hand drying device 100 according to embodiment 1 will be described with reference to fig. 1 to 4. Fig. 1 is a view of a commode 400 provided with a hand dryer 100 according to embodiment 1, as viewed from above. Fig. 2 is a sectional view of a commode 400 provided with the hand dryer 100 according to embodiment 1, and is a sectional view showing a section a-a in fig. 1. Fig. 3 is a sectional view of a commode 400 provided with the hand dryer 100 according to embodiment 1, and is a sectional view showing a section B-B in fig. 1. Fig. 4 is a sectional view of a commode 400 provided with the hand dryer 100 according to embodiment 1, and is a sectional view showing a section C-C of fig. 1.

For convenience of explanation, in fig. 1 to 4, the x-axis direction is defined as the front-rear direction, the y-axis direction is defined as the left-right direction, and the z-axis direction is defined as the up-down direction. The positive direction of the z-axis direction is defined as an upward direction.

As shown in fig. 1 and 2, the hand drying device 100, the water discharge device 200, and the detergent discharge device 300 are arranged in the horizontal direction on the box-shaped commode 400. The hand drying device 100 blows a high-speed airflow and blows off water adhering to the hands, thereby drying the hands. The hand dryer 100 is fixed to the commode 400 through a through hole 401 formed in the commode 400.

The water discharge device 200 discharges water for washing hands. The water discharge device 200 is fixed to the commode 400 by passing through a through-hole 402 formed in the commode 400. As shown in fig. 3, the water discharge device 200 has a water discharge pipe 210 through which water flows. A water discharge port 211 for discharging water is formed at the water discharge pipe 210. The water discharge device 200 may be a device that automatically discharges water by detecting a hand using a sensor such as an infrared sensor, or may be a device that manually discharges water by pressing a button.

The detergent discharge device 300 discharges detergent for cleaning hands. The detergent discharge device 300 is fixed to the commode 400 by penetrating through a through hole 403 formed in the commode 400. The detergent discharge device 300 has a detergent discharge pipe 310 through which detergent flows. A detergent discharge port 311 for discharging detergent is formed in the detergent discharge pipe 310. The detergent discharge device 300 may be a device that automatically discharges detergent by detecting a hand with a sensor such as an infrared sensor, or may be a device that manually discharges detergent by pressing a button.

The commode 400 is provided on the floor 501 in such a manner as to be connected to the wall 500. A bowl-shaped sink 410 is provided above the commode 400. The washbasin 410 receives the air flow blown out from the hand drying device 100, the water discharged from the water discharge device 200, and the detergent discharged from the detergent discharge device 300. A drain port 411 for draining water is formed in the bottom surface of the washbasin 410. A drain pipe 600 is connected to the drain port 411.

As shown in fig. 4, the hand dryer 100 includes a cabinet 10 provided below a commode 400, a main body 20 provided above the commode 400, and a duct 30 connecting the cabinet 10 and the main body 20.

The cabinet 10 is housed inside the commode 400. In embodiment 1, the housing 10 is mounted on a wall 500. The casing 10 may be provided on the floor 501. A blower 2 for generating a high-pressure air flow and a control unit 40 for controlling the blower 2 are provided inside the casing 10. An air filter, not shown, is detachably attached to the intake side of the blower 2. The air filter traps dust and dirt in the air. As the air filter, for example, a mesh filter or a HEPA (High Efficiency Particulate air) filter is used. One end of a duct 30 is connected to the exhaust side of the blower 2.

The other end of the pipe 30 is connected to the main body 20. A ventilation passage 31 through which the air flow generated by the blower 2 passes is formed inside the duct 30. In order to improve workability, the duct 30 is made of a flexible and bendable resin. The duct 30 may be made of metal such as stainless steel.

The main body 20 is fixed to the commode 400 through a through hole 401 formed in the commode 400. In the case where the wash stand 400 is not provided with the detergent discharge device 300, the main body 20 may be inserted into the through hole 403 for inserting the detergent discharge pipe 310. The main body 20 may be fixed to the wall 500 above the commode 400 instead of the commode 400.

The main body 20 is provided with a nozzle 3 for blowing an air flow toward the drying space 50 for drying the hands. One end of the nozzle 3 is connected to the pipe 30. An outlet port 3a for blowing out the air flow generated by the blower 2 is formed at the other end of the nozzle 3. The drying space 50 is a space formed below the air outlet 3a of the nozzle 3 and between the air outlet 3a and the bottom of the washbasin 410.

Further, the hand dryer 100 includes the electrostatic capacity sensor 4. The capacitance sensor 4 is a mutual capacitance type capacitance sensor that includes two electrodes and detects capacitance between the two electrodes. The capacitance sensor 4 includes a first electrode 4a, a second electrode 4b, and a circuit portion, not shown, which is connected to the first electrode 4a and the second electrode 4b and detects capacitance between the first electrode 4a and the second electrode 4 b. The capacitance sensor 4 is connected to the control unit 40 through a wiring not shown.

In embodiment 1, the first electrode 4a is provided inside the main body 20, and the second electrode 4b is provided inside the duct 30. Specifically, the first electrode 4a is disposed above the through hole 401 of the commode 400 in the main body 20, and the second electrode 4b is disposed below the through hole 401 in the duct 30.

The first electrode 4a and the second electrode 4b are, for example, rectangular parallelepiped in shape, and are arranged vertically with their principal surfaces parallel to each other. The first electrode 4a and the second electrode 4b are provided so that the main surfaces thereof face forward, that is, in a direction in which the drying space 50 and the washbasin 410 are located. Accordingly, the capacitance sensor 4 can detect the capacitance in the drying processing space 50 and the wash basin 410.

The first electrode 4a is provided outside the nozzle 3 inside the body 20 in order to prevent collision of high-speed air flows passing through the inside of the nozzle 3. The second electrode 4b is provided outside the ventilation passage 31 inside the duct 30 in order to prevent collision of high-speed air flows passing through the ventilation passage 31.

Here, the principle of the mutual capacitance type electrostatic capacity sensor 4 will be described with reference to fig. 5 and 6. Fig. 5 is a schematic diagram for explaining the principle of the capacitance sensor 4 of the hand dryer 100 according to embodiment 1, and is a diagram showing a state where a hand does not approach the capacitance sensor 4. Fig. 6 is a schematic diagram for explaining the principle of the capacitance sensor 4 of the hand drying device 100 according to embodiment 1, and is a diagram showing a state in which a hand approaches the capacitance sensor 4.

As shown in fig. 5, the capacitance sensor 4 applies a voltage from the circuit portion to the second electrode 4b to form an electric field between the second electrode and the first electrode 4a, and detects capacitance formed between the first electrode 4a and the second electrode 4 b. When a potential difference is generated between the first electrode 4a and the second electrode 4b, an electric field based on capacitive coupling is formed between the first electrode 4a and the second electrode 4 b. Since the size of the capacitance is inversely proportional to the distance between the first electrode 4a and the second electrode 4b, the capacitance increases when a conductor such as a metal approaches between the first electrode 4a and the second electrode 4 b. In addition, when a dielectric such as water having a dielectric constant larger than that of air is close to each other, the capacitance between the first electrode 4a and the second electrode 4b is also increased.

As shown in fig. 6, when a conductor that is a part of a human body such as a hand approaches between the first electrode 4a and the second electrode 4b, a part of the electric field is guided to the human body, and the capacitance between the first electrode 4a and the second electrode 4b is reduced. That is, since it can be considered that the human body is grounded near the gap between the first electrode 4a and the second electrode 4b, the electrostatic shielding state is achieved, and the electrostatic capacitance between the first electrode 4a and the second electrode 4b is reduced. In this way, when a grounded conductor such as a hand is brought close to between the first electrode 4a and the second electrode 4b, the capacitance between the first electrode 4a and the second electrode 4b is reduced.

In the present embodiment, when water is present in the wash basin 410, the capacitance between the first electrode 4a and the second electrode 4b increases, and when the drying processing space 50 has hands, the capacitance between the first electrode 4a and the second electrode 4b decreases. Therefore, the presence of water in the wash basin 410 is detected when the capacitance detected by the capacitance sensor 4 is equal to or greater than a water detection threshold for determining whether or not water is present in the wash basin 410, and the presence of a hand in the drying processing space 50 is detected when the capacitance detected by the capacitance sensor 4 is equal to or less than a hand detection threshold for determining whether or not the drying processing space 50 has a hand, whereby the presence of a hand in the drying processing space 50 and the presence of water in the wash basin 410 can be detected by one capacitance sensor 4. The phrase "water is present in the washbasin 410" means, for example, "water is accumulated in the washbasin 410" or "water discharged from the water discharge device 200 flows in the washbasin 410".

Next, the configuration of the control system of the hand drying device 100 will be described with reference to fig. 7. Fig. 7 is a block diagram showing the configuration of a control system of the hand dryer 100 according to embodiment 1.

As shown in fig. 7, the control unit 40 receives the detection result of the electrostatic capacity sensor 4 as a signal. The control unit 40 controls the operation of the blower 2 based on the received signal.

The control unit 40 includes a detection unit 41 and an operation control unit 42. The detection unit 41 detects the presence or absence of hands in the drying processing space 50 and the presence or absence of water in the washbasin 410 based on the capacitance detected by the capacitance sensor 4. The detection unit 41 sends the detection results of the presence or absence of hands in the drying space 50 and the presence or absence of water in the washbasin 410 to the operation control unit 42 as signals. The operation control unit 42 controls the operation of the blower 2 based on the detection result of the detection unit 41.

The control unit 40 is realized as a processing circuit having a hardware configuration shown in fig. 8, for example. Fig. 8 is a diagram showing an example of a hardware configuration of a processing circuit according to embodiment 1. As shown in fig. 8, the control unit 40 includes, for example, a processor 91 as an arithmetic unit and a memory 92 as a storage unit. The processor 91 executes the program stored in the memory 92, thereby realizing each function of the control unit 40. That is, the control of the detection unit 41 and the operation control unit 42 is realized by the processor 91 and the memory 92. Further, the respective functions of the control unit 40 may be realized by a plurality of processors and a plurality of memories in cooperation.

Next, the operation of the hand dryer 100 of the present embodiment will be described. When the user places his or her hand in the drying processing space 50 after washing the hand, the detection unit 41 receives the detection result of the capacitance sensor 4 and detects that the hand is present in the drying processing space 50. The operation control unit 42 receives the detection result of the detection unit 41 and drives the blower 2. Accordingly, the high-speed air flow generated by the blower 2 is blown out from the nozzle 3, and water droplets adhering to the hand are blown off. The blown-off water drops down into the wash basin 410 and is discharged through the drain opening 411.

Here, the wash basin 410 is provided with a non-illustrated shutoff valve that can close the drain opening 411. Therefore, the user may want to dry his or her hands while the water is stored in the washbasin 410. At this time, the high-speed airflow blown out from the nozzle 3 may collide with water stored in the wash basin 410 without touching the hands, and the water may scatter. Even when water is not stored in the sink 410, when water is discharged from the water discharge device 200, a high-speed air flow collides with the water discharged from the water discharge device 200, and the water may scatter. Therefore, in the present embodiment, the presence or absence of water in the wash basin 410 is detected based on the capacitance detected by the capacitance sensor 4, and when water is present in the wash basin 410, the drive of the blower 2 is stopped.

Next, the operation of the control unit 40 will be described with reference to fig. 9. Fig. 9 is a flowchart illustrating an operation of the control unit 40 according to embodiment 1.

When the power of the hand drying device 100 is turned on, the control unit 40 starts control from "start" in fig. 9. In step S1, the detection unit 41 updates the reference value. The reference value is a value obtained from the capacitance detected by the capacitance sensor 4, and is, for example, an average value of the capacitances detected by the capacitance sensor 4.

Next, in step S2, the detection unit 41 sets a water detection threshold for determining whether or not water is present in the washbasin 410 and a hand detection threshold for determining whether or not a hand is present in the drying processing space 50. In embodiment 1, the water detection threshold value includes a first water detection threshold value, and the hand detection threshold value includes a first hand detection threshold value and a second hand detection threshold value.

The detection unit 41 sets the first water detection threshold by adding the first fixed value to the reference value updated in step S1. The detection unit 41 subtracts a second fixed value from the reference value to set a first hand detection threshold value. The detection unit 41 sets the second hand detection threshold by adding a first fixed value to the first hand detection threshold. That is, the first hand detection threshold is smaller than the first water detection threshold, and the second hand detection threshold is larger than the first hand detection threshold.

The capacitance detected by the capacitance sensor 4 varies depending on the temperature, the installation state of the conductor around, and other changes in the installation environment of the hand dryer 100, and changes with time. Therefore, by updating the reference value based on the capacitance detected by the capacitance sensor 4 and setting the first water detection threshold value, the first hand detection threshold value, and the second hand detection threshold value based on the reference value, it is possible to eliminate the influence of changes in the installation environment of the hand drying device 100 and changes over time.

Here, the first water detection threshold may be set so that the capacitance detected by the capacitance sensor 4 becomes equal to or greater than the first water detection threshold when water is accumulated in the wash basin 410, or may be set so that the capacitance detected by the capacitance sensor 4 becomes equal to or greater than the first water detection threshold when water discharged from the water discharge device 200 flows through the wash basin 410.

The first hand detection threshold value is set so that the capacitance detected by the capacitance sensor 4 becomes equal to or less than the first hand detection threshold value when there is no water in the wash basin 410 and there is a hand in the drying processing space 50. The second hand detection threshold is set so that the capacitance detected by the capacitance sensor 4 when water is present in the washbasin 410 and hands are present in the drying processing space 50 is equal to or less than the second hand detection threshold. The second hand detection threshold is set by adding a first fixed value to the first hand detection threshold, but a value different from the first fixed value may be added.

Next, in step S3, the detection unit 41 determines whether or not a first set time has elapsed after setting the first water detection threshold, the first hand detection threshold, and the second hand detection threshold. The first set time is a preset value and is a time corresponding to the update cycle of the water detection threshold and the hand detection threshold. The first set time is stored in the detection unit 41.

When the detection unit 41 determines in step S3 that the first set time has elapsed after the first water detection threshold, the first hand detection threshold, and the second hand detection threshold have been set, the process returns to step S1 to update the reference value, and the first water detection threshold, the first hand detection threshold, and the second hand detection threshold are set again.

This allows the first water detection threshold value, the first hand detection threshold value, and the second hand detection threshold value to be periodically updated, and thus, the influence of the change in the installation environment of the hand drying device 100 and the change over time can be eliminated.

If the detection unit 41 determines in step S3 that the first set time has not elapsed after setting the first water detection threshold, the first hand detection threshold, and the second hand detection threshold, the routine proceeds to step S4.

In step S4, the detection unit 41 determines whether or not the capacitance detected by the capacitance sensor 4 is equal to or greater than a first water detection threshold. The detection unit 41 detects that water is present in the wash basin 410 when the capacitance detected by the capacitance sensor 4 is equal to or greater than the first water detection threshold, and detects that water is not present in the wash basin 410 when the capacitance detected by the capacitance sensor 4 is smaller than the first water detection threshold.

When the detection unit 41 determines in step S4 that the capacitance detected by the capacitance sensor 4 is equal to or greater than the first water detection threshold, the routine proceeds to step S5. In step S5, the detection unit 41 determines whether or not the capacitance detected by the capacitance sensor 4 is equal to or less than a second hand detection threshold. The detection unit 41 detects that a hand is present in the drying processing space 50 when the capacitance detected by the capacitance sensor 4 is equal to or less than the second hand detection threshold, and detects that no hand is present in the drying processing space 50 when the capacitance detected by the capacitance sensor 4 is greater than the second hand detection threshold.

When the detection unit 41 determines in step S5 that the capacitance detected by the capacitance sensor 4 is equal to or less than the second hand detection threshold, the process returns to step S5, and step S5 is repeated until it is determined that the capacitance detected by the capacitance sensor 4 is greater than the second hand detection threshold. In this way, even if the capacitance detected by the capacitance sensor 4 is equal to or less than the second hand detection threshold value and it is detected that the hand is present in the drying processing space 50 in step S5, the driving of the blower 2 is stopped, and therefore, it is possible to prevent the water in the wash basin 410 from scattering due to the driving of the blower 2 when the water is present in the wash basin 410.

When the detection unit 41 determines in step S5 that the capacitance detected by the capacitance sensor 4 is larger than the second hand detection threshold, the routine proceeds to step S4. The operations of step S4 and step S5 are repeated until the detection unit 41 determines in step S4 that the capacitance detected by the capacitance sensor 4 is smaller than the first water detection threshold. When the detection unit 41 determines in step S4 that the capacitance detected by the capacitance sensor 4 is smaller than the first water detection threshold value and detects that there is no water in the wash basin 410, the routine proceeds to step S6.

In step S6, the detection unit 41 determines whether or not the capacitance detected by the capacitance sensor 4 is equal to or less than a first-hand detection threshold value. The detection unit 41 detects that a hand is present in the drying processing space 50 when the capacitance detected by the capacitance sensor 4 is equal to or less than the first-hand detection threshold value, and detects that no hand is present in the drying processing space 50 when the capacitance is greater than the first-hand detection threshold value.

When it is determined in step S6 that the capacitance detected by the capacitance sensor 4 is larger than the first hand detection threshold value, the process returns to step S3. When it is determined in step S6 that the capacitance detected by the capacitance sensor 4 is equal to or less than the first hand detection threshold value, the process proceeds to step S7, and the operation control unit 42 drives the blower 2 at the first air volume.

When the operation control unit 42 drives the blower 2 in step S7, the detection unit 41 determines whether or not the capacitance detected by the capacitance sensor 4 is equal to or less than the first-hand detection threshold value in step S8. When the detection unit 41 determines in step S8 that the capacitance detected by the capacitance sensor 4 is equal to or less than the first-hand detection threshold value, the process returns to step S8, and step S8 is repeated until it is determined that the capacitance detected by the capacitance sensor 4 is greater than the first-hand detection threshold value.

When the detection unit 41 determines in step S8 that the capacitance detected by the capacitance sensor 4 is larger than the first-hand detection threshold value, the routine proceeds to step S9, and the operation control unit 42 stops the driving of the blower 2. When the operation control unit 42 stops the driving of the blower 2 in step S9, the process proceeds to step S3.

Fig. 10 is a timing chart showing changes in capacitance detected by the capacitance sensor 4 of the hand dryer 100 according to embodiment 1. In fig. 10, the first water detection threshold value is indicated by a broken line, the first hand detection threshold value and the second hand detection threshold value are indicated by a one-dot chain line, and the capacitance detected by the capacitance sensor 4 is indicated by a solid line. The time intervals at times T0, T1, T2, T3, T4, T5, T6, T8, T9, and T10 are update periods of the first water detection threshold, the first hand detection threshold, and the second hand detection threshold.

At time T1, the detection unit 41 updates the reference value, and further updates the first water detection threshold value, the first hand detection threshold value, and the second hand detection threshold value. At time T1a, water begins to accumulate within the lavatory 410. At time T1b, the capacitance detected by the capacitance sensor 4 becomes equal to or greater than the first water detection threshold, and the detection unit 41 detects that water is present in the washbasin 410. At times T2 and T3, the capacitance detected by the capacitance sensor 4 is equal to or greater than the first water detection threshold value and it is detected that water is present in the wash basin 410, and therefore the detection unit 41 stops updating the first water detection threshold value, the first hand detection threshold value, and the second hand detection threshold value.

At time T3a, when the hand is placed in the drying processing space 50, the capacitance detected by the capacitance sensor 4 becomes equal to or less than the second hand detection threshold, and the detection unit 41 detects that the hand is present in the drying processing space 50. In embodiment 1, at time T3a, even if the detection unit 41 detects that there is a hand in the drying processing space 50, the operation control unit 42 stops the driving of the blower 2. At times T4 and T5, the capacitance detected by the capacitance sensor 4 is equal to or greater than the first water detection threshold value and it is detected that water is present in the wash basin 410, and therefore the detection unit 41 stops updating the first water detection threshold value, the first hand detection threshold value, and the second hand detection threshold value.

At time T4a, the water in the lavatory 410 begins to drain. At time T5a, when the capacitance detected by the capacitance sensor 4 is lower than the first water detection threshold, the detection unit 41 detects that there is no water in the wash basin 410. At times T6 and T7, the detection unit 41 updates the reference value, and further updates the first water detection threshold, the first hand detection threshold, and the second hand detection threshold.

At time T7a, when the hand is placed in the drying processing space 50, the capacitance detected by the capacitance sensor 4 becomes equal to or less than the first hand detection threshold value, and the detection unit 41 detects that the hand is present in the drying processing space 50. At time T7a, the detection unit 41 detects that there is no water in the washbasin 410 and that there is a hand in the drying processing space 50, and therefore the operation control unit 42 drives the blower 2 at the first air volume. At times T8, T9, and T10, the detector 41 updates the reference value, and further updates the first water detection threshold, the first hand detection threshold, and the second hand detection threshold.

According to the hand drying device 100 of embodiment 1, the presence or absence of the hands in the drying processing space 50 and the presence or absence of the water in the washbasin 410 are detected by the single capacitance sensor 4, so that it is not necessary to provide a sensor for detecting the presence or absence of the water in the washbasin 410 separately from the sensor for detecting the presence or absence of the hands. This enables realization of the hand drying device 100 having the hand detection function and the water detection function while suppressing an increase in cost.

Further, since there is no need to provide a space for providing a sensor for detecting the presence or absence of water in the wash basin 410 separately from a space for providing a sensor for detecting the presence or absence of hands, the hand drying device 100 having the hand detection function and the water detection function can be realized while suppressing an increase in size of the hand drying device 100.

Further, when a sensor for detecting the presence or absence of water in the wash basin 410 is used separately from a sensor for detecting the presence or absence of hands, the reference value needs to be updated by each sensor.

Further, since the blower 2 is driven only when there is no water in the washbasin 410 and the drying processing space 50 has hands, it is possible to prevent the water in the washbasin 410 from scattering by driving the blower 2 when there is water in the washbasin 410.

Further, when there is no water in the wash basin 410 and there is no hand in the drying processing space 50, the reference value is periodically updated to set the water detection threshold and the hand detection threshold, and therefore, it is possible to eliminate the influence of changes in the installation environment of the hand drying device 100, such as the temperature and the installation state of the surrounding conductors, and changes over time.

Further, since the update of the reference value is stopped when water is present in the wash basin 410 and when the hand is present in the drying processing space 50, it is possible to prevent the water detection threshold value and the hand detection threshold value from being changed to erroneous values when the reference value is updated when water is present in the wash basin 410 and when the hand is present in the drying processing space 50.

In embodiment 1, the first electrode 4a is provided inside the main body 20 and the second electrode 4b is provided inside the duct 30, but both the first electrode 4a and the second electrode 4b may be provided inside the main body 20 or both may be provided inside the duct 30. Further, the first electrode 4a and the second electrode 4b are provided so as to sandwich the through hole 401 of the commode 400 in the vertical direction, but both the first electrode 4a and the second electrode 4b may be provided at a position above the through hole 401 or both may be provided at a position below the through hole 401. Even in this case, the control of embodiment 1 can be performed if the main surfaces of the first electrode 4a and the second electrode 4b are provided so as to face forward, that is, in the direction in which the drying processing space 50 and the wash basin 410 are located, and the electrostatic capacitance in the drying processing space 50 and the wash basin 410 can be detected.

The first electrode 4a and the second electrode 4b may be provided outside the hand drying device 100, and may not be provided inside the main body 20 or inside the duct 30. Fig. 11 is a sectional view of a commode 400 provided with the hand dryer 100 according to the modification of embodiment 1, and is a sectional view showing a section C-C of fig. 1. Fig. 12 is a sectional view of a commode 400 provided with the hand dryer 100 according to the modification of embodiment 1, and is a sectional view showing a section C-C of fig. 1.

As shown in fig. 11, the first electrode 4a may be attached to the outer surface of the body 20, and the second electrode 4b may be attached to the outer surface of the pipe 30. As shown in fig. 12, the first electrode 4a and the second electrode 4b may be attached to the outer surface of the sink 410, that is, the outer periphery of the sink 410, on the inner side of the washstand 400. Even in this case, the control of embodiment 1 can be performed if the main surfaces of the first electrode 4a and the second electrode 4b are provided so as to face forward, that is, in the direction in which the drying processing space 50 and the wash basin 410 are located, and the electrostatic capacitance in the drying processing space 50 and the wash basin 410 can be detected.

In embodiment 1, the first electrode 4a and the second electrode 4b are arranged in the vertical direction with the principal surfaces parallel to each other and the side surfaces facing each other, but the positional relationship between the first electrode 4a and the second electrode 4b is not limited to this. Fig. 13 is a sectional view of a commode 400 provided with the hand dryer 100 according to the modification of embodiment 1, and is a sectional view showing a section C-C of fig. 1. Fig. 14 is a sectional view of a commode 400 provided with the hand dryer 100 according to the modification of embodiment 1, and is a sectional view showing a section C-C of fig. 1.

As shown in fig. 13, the first electrode 4a may be provided at a position forward of the outlet port 3a of the nozzle 3 in the main body 20 so that the main surface thereof faces downward, and the second electrode 4b may be provided at a position rearward of the outlet port 3a of the nozzle 3 in the main body 20 so that the main surface thereof faces downward. As shown in fig. 14, the first electrode 4a may be provided at a position forward of the outlet port 3a of the nozzle 3 in the main body 20 so that the main surface thereof faces downward, and the second electrode 4b may be provided at a position rearward of the outlet port 3a of the nozzle 3 in the main body 20 so that the main surface thereof faces forward. In this case, it is necessary to expand the detection range so that the electrostatic capacitance in the drying processing space 50 and the wash basin 410 can be detected by the electrostatic capacitance sensor 4, and the accuracy of detecting the presence or absence of the hands in the drying processing space 50 and the presence or absence of the water in the wash basin 410 is lowered, but the control of embodiment 1 can be performed if the main surfaces of the first electrode 4a and the second electrode 4b are provided so as to face the direction in which the drying processing space 50 and the wash basin 410 are located, and the electrostatic capacitance in the drying processing space 50 and the wash basin 410 can be detected.

In embodiment 1, the detection unit 41 inside the control unit 40 detects the presence or absence of hands in the drying processing space 50 and the presence or absence of water in the wash basin 410 based on the capacitance detected by the capacitance sensor 4, but the detection unit 41 may be provided outside the control unit 40. For example, the detection unit 41 may be provided inside the capacitance sensor 4, and the operation control unit 42 in the control unit 40 may receive the detection result of the detection unit 41 inside the capacitance sensor 4 as a signal to control the operation of the blower 2.

Embodiment 2.

In embodiment 2, the hand dryer 100 has the same configuration as that of embodiment 1, but the operation of the control unit 40 is different from that of embodiment 1. In embodiment 1, when the presence of water in the washbasin 410 is detected, the drive of the blower 2 is stopped even if the presence of a hand in the drying processing space 50 is detected. On the other hand, in embodiment 2, when it is detected that water is present in the washbasin 410 and when it is detected that hands are present in the drying processing space 50, the blower 2 is driven with a smaller air volume than when water is not present in the washbasin 410. Items not specifically described are the same as those in embodiment 1, and the same functions and structures are described using the same reference numerals. Note that description of the same functions and configurations as those in embodiment 1 is omitted.

Fig. 15 is a flowchart showing the operation of the control unit 40 according to embodiment 2. When the detection unit 41 determines in step S4 that the capacitance detected by the capacitance sensor 4 is equal to or greater than the first water detection threshold, the routine proceeds to step S5. In step S5, the detection unit 41 determines whether or not the capacitance detected by the capacitance sensor 4 is equal to or less than a second hand detection threshold.

When the detection unit 41 determines in step S5 that the capacitance detected by the capacitance sensor 4 is larger than the second hand detection threshold, the process returns to step S4. When the detection unit 41 determines in step S5 that the capacitance detected by the capacitance sensor 4 is equal to or less than the second hand detection threshold, the routine proceeds to step S10.

In step S10, the operation control unit 42 drives the blower 2 at the second air flow rate. The second air volume is smaller than the first air volume that is the air volume when the blower 2 is driven in step S7. For example, if the operation control unit 42 can drive the blower 2 with 2 air volumes of "strong" and "weak", the first air volume is "strong" and the second air volume is "weak".

Next, in step S11, the detection unit 41 determines whether or not the capacitance detected by the capacitance sensor 4 is equal to or less than a second hand detection threshold value. When the detection unit 41 determines in step S11 that the capacitance detected by the capacitance sensor 4 is equal to or less than the second hand detection threshold, the process returns to step S11, and step S11 is repeated until it is determined that the capacitance detected by the capacitance sensor 4 is greater than the second hand detection threshold.

When the detection unit 41 determines in step S11 that the capacitance detected by the capacitance sensor 4 is greater than the second hand detection threshold, the routine proceeds to step S12, and the operation control unit 42 stops driving of the blower 2. When the drive of the blower 2 is stopped in step S12, the process proceeds to step S4.

In the hand drying device 100 according to embodiment 1, since the driving of the blower 2 is stopped when water is present in the washbasin 410, there is a problem that the hands cannot be dried when water is present in the washbasin 410 and the usability is poor. According to the hand drying device 100 of embodiment 2, since the blower 2 is driven at the second air volume smaller than the first air volume when water is present in the washbasin 410 and hands are present in the drying processing space 50, it is possible to dry the hands while suppressing scattering of the water in the washbasin 410 even when water is present in the washbasin 410.

Embodiment 3.

In embodiment 3, the hand dryer 100 has the same configuration as that of embodiment 2, but the operation of the control unit 40 is different from that of embodiment 2. In embodiment 3, a second water detection threshold value for determining whether the wash basin 410 is full of water is provided. Items not specifically described are the same as those in embodiment 2, and the same functions and structures are described using the same reference numerals. Note that descriptions of the same functions and configurations as those in embodiment 2 are omitted.

Fig. 16 is a flowchart illustrating the operation of the control unit 40 according to embodiment 3. When the reference value is updated in step S1, the process proceeds to step S21. In step S21, the detection unit 41 sets a water detection threshold value and a hand detection threshold value. In embodiment 3, the water detection threshold value includes a first water detection threshold value and a second water detection threshold value, and the hand detection threshold value includes a first hand detection threshold value and a second hand detection threshold value.

The detection unit 41 sets the first water detection threshold by adding the first fixed value to the reference value updated in step S1, and sets the second water detection threshold by adding the third fixed value to the reference value. The third fixed value is greater than the first fixed value. That is, the second water detection threshold is greater than the first water detection threshold. The detection unit 41 sets the first hand detection threshold by subtracting the second fixed value from the reference value, and sets the second hand detection threshold by adding the first fixed value to the first hand detection threshold.

The second water detection threshold is a value for determining whether or not the interior of the wash basin 410 is full of water, and is set so that the capacitance detected by the capacitance sensor 4 is equal to or greater than the second water detection threshold when the interior of the wash basin 410 is full of water. Here, the full water means a state in which more than 8 of the capacity of the washbasin 410 is filled with water. The full water is not limited to the state in which the volume of the washbasin 410 is 8 or more full of water, and means a state in which the inside of the washbasin 410 is full of water to such an extent that the water in the washbasin 410 may be scattered even if the blower 2 is driven at the second air flow rate smaller than the first air flow rate.

Next, in step S22, the detection unit 41 determines whether or not a first set time set in advance has elapsed after setting the first water detection threshold, the second water detection threshold, the first hand detection threshold, and the second hand detection threshold. When the detection unit 41 determines that the first set time has elapsed after the first water detection threshold, the second water detection threshold, the first hand detection threshold, and the second hand detection threshold have been set, the process returns to step S1. When the detection unit 41 determines in step S22 that the first set time has not elapsed after setting the first water detection threshold, the second water detection threshold, the first hand detection threshold, and the second hand detection threshold, the routine proceeds to step S23.

In step S23, the detection unit 41 determines whether or not the capacitance detected by the capacitance sensor 4 is equal to or greater than a second water detection threshold value. The detection unit 41 detects that the inside of the wash basin 410 is full when the capacitance detected by the capacitance sensor 4 is equal to or greater than the second water detection threshold, and detects that the inside of the wash basin 410 is not full when the capacitance detected by the capacitance sensor 4 is smaller than the second water detection threshold.

When the detection unit 41 determines in step S23 that the capacitance detected by the capacitance sensor 4 is equal to or greater than the second water detection threshold, the process returns to step S23 again, and step S23 is repeated until it is determined that the capacitance detected by the capacitance sensor 4 is smaller than the second water detection threshold. When the detection unit 41 determines in step S23 that the capacitance detected by the capacitance sensor 4 is smaller than the second water detection threshold, the routine proceeds to step S4.

In the hand drying device 100 according to embodiment 2, when water is present in the washbasin 410 and hands are present in the drying processing space 50, the blower 2 is driven at the second air flow rate smaller than the first air flow rate even when the washbasin 410 is filled with water, and therefore there is a possibility that the water in the washbasin 410 may scatter. According to the hand drying device 100 of embodiment 3, when the wash basin 410 is full of water, the driving of the blower 2 is stopped, and therefore, the water in the wash basin 410 can be prevented from scattering.

In addition, when the wash basin 410 is not filled with water, the blower 2 is driven at the second air flow rate smaller than the first air flow rate even when water is present in the wash basin 410, and therefore, the hands can be dried while preventing the water in the wash basin 410 from scattering.

As described above, according to the hand drying device 100 of embodiment 3, the operation of the blower 2 can be changed according to the amount of water in the washbasin 410. In embodiment 3, the first water detection threshold and the second water detection threshold are set as the water detection thresholds, but the air volume of the blower 2 may be adjusted according to the amount of water in the wash basin 410 by setting the water detection thresholds to 3 or more according to the amount of water in the wash basin 410.

Embodiment 4.

In embodiment 4, the hand dryer 100 is different from embodiments 1 to 3 in structure. The hand drying device 100 according to embodiments 1 to 3 includes the case 10, the main body 20, and the duct 30, but the hand drying device 100 according to embodiment 4 includes the main body 60 provided on the commode 400. Items not specifically described are the same as those in embodiments 1 to 3, and the same functions and structures are described using the same reference numerals. In addition, descriptions of the same functions and structures as those of embodiments 1 to 3 are omitted.

Fig. 17 is a view of the commode 400 provided with the hand drying device 100 according to embodiment 4, as viewed from above. Fig. 18 is a sectional view of a commode 400 provided with the hand dryer 100 according to embodiment 4, and is a sectional view showing a section C-C in fig. 17.

As shown in fig. 18, a main body 60 provided on a commode 400 is provided with a blower 2 for generating a high-pressure air flow, a control unit 40 for controlling the blower 2, and a nozzle 3 for blowing the air flow toward a drying space 50 for drying hands. The main body 60 is fixed to the commode 400 by inserting the screw 5 into a through hole 404 formed in the commode 400 and fastening the screw to a screw hole, not shown, formed in the main body 60.

In embodiment 4, the first electrode 4a of the capacitance sensor 4 is provided at the lower portion of the main body 60 such that the main surface thereof faces forward, i.e., in the direction in which the drying processing space 50 and the wash basin 410 are located. The second electrode 4b of the capacitive sensor 4 is provided on the outer surface of the washbasin 410, that is, on the outer periphery of the washbasin 410, on the inner side of the washstand 400.

The first electrode 4a and the second electrode 4b may be both provided on the outer surface of the washbasin 410, or both may be provided inside the main body 60.

The operation of the control unit 40 according to embodiment 4 is the same as that of embodiments 1 to 3, and therefore, the description thereof is omitted.

As in the hand drying device 100 according to embodiment 4, even if the structure of the hand drying device 100 is different from that of embodiments 1 to 3, the same effects as those of embodiments 1 to 3 can be obtained as long as the electrostatic capacitance in the drying processing space 50 and the washbasin 410 can be detected by the first electrode 4a and the second electrode 4 b.

Embodiment 5.

In embodiments 1 to 4, the presence or absence of hands in the drying processing space 50 and the presence or absence of water in the washbasin 410 are detected based on the capacitance detected by the capacitance sensor 4. On the other hand, in embodiment 5, the presence or absence of hands in the drying processing space 50 and the presence or absence of water in the washbasin 410 are detected by using the infrared sensor 6 instead of the capacitance sensor 4. Items not specifically described are the same as those in embodiments 1 to 4, and the same functions and structures are described using the same reference numerals. Note that descriptions of the same functions and structures as those in embodiments 1 to 4 are omitted.

Fig. 19 is a sectional view of a commode 400 provided with the hand dryer 100 according to embodiment 5, which corresponds to the section C-C in fig. 1. As shown in fig. 19, the hand dryer 100 includes an infrared sensor 6 instead of the electrostatic capacity sensor 4. The infrared sensor 6 is provided, for example, inside the main body 20, at a position forward of the outlet port 3a of the nozzle 3.

The infrared sensor 6 includes an infrared light emitting element that emits infrared light and an infrared light receiving element that receives infrared light emitted from the infrared light emitting element, and detects the amount of received infrared light received by the infrared light receiving element. The infrared sensor 6 is connected to the control unit 40 through a wiring not shown.

The infrared sensor 6 is provided so that the infrared light emitting element emits infrared light toward the inside of the washbasin 410. The infrared light receiving element receives infrared light emitted from the infrared light emitting element and reflected by the washbasin 410, and outputs a signal indicating the amount of received infrared light to the detection unit 41.

The detection unit 41 detects the presence or absence of hands in the drying space 50 and the presence or absence of water in the washbasin 410 based on the amount of received infrared light detected by the infrared sensor 6. The operation control unit 42 controls the operation of the blower 2 based on the detection result of the detection unit 41.

Here, when the drying processing space 50 has a hand, the infrared rays emitted from the infrared ray emitting elements are reflected by the hand, and thus the amount of received infrared rays increases. When water is present in the washbasin 410, the infrared ray emitted from the infrared ray emitting element is absorbed by the water, and thus the amount of infrared ray received decreases.

Therefore, by detecting that water is present in the washbasin 410 when the amount of received infrared light detected by the infrared sensor 6 is equal to or less than a water detection threshold for determining whether water is present in the washbasin 410, and detecting that a hand is present in the drying processing space 50 when the amount of received infrared light detected by the infrared sensor 6 is equal to or more than a hand detection threshold for determining whether a hand is present in the drying processing space 50, the presence or absence of a hand in the drying processing space 50 and the presence or absence of water in the washbasin 410 can be detected by one infrared sensor 6.

The operation of the control unit 40 will be described with reference to fig. 20. Fig. 20 is a flowchart showing the operation of the control unit 40 according to embodiment 5.

In step S31, the detection unit 41 updates the reference value. The reference value is a value obtained from the amount of received infrared light detected by the infrared sensor 6, and is, for example, an average value of the amount of received infrared light detected by the infrared sensor 6.

In step S32, the detection unit 41 sets a water detection threshold for determining whether or not water is present in the washbasin 410 and a hand detection threshold for determining whether or not a hand is present in the drying processing space 50. In embodiment 5, a third water detection threshold value is provided as the water detection threshold value, and a third hand detection threshold value is provided as the hand detection threshold value. The detection section 41 sets a third water detection threshold by subtracting a third fixed value from the reference value updated in step S31. The detection unit 41 sets the third hand detection threshold by adding a fourth fixed value to the reference value.

In step S33, the detection unit 41 determines whether or not a first set time set in advance has elapsed after setting the third water detection threshold and the third hand detection threshold. When the detection unit 41 determines that the first setting time has elapsed after the third water detection threshold and the third hand detection threshold have been set, the process returns to step S31 to update the reference value, and the third water detection threshold and the third hand detection threshold are set again.

If the detection unit 41 determines in step S33 that the first set time has not elapsed after setting the third water detection threshold and the third hand detection threshold, the routine proceeds to step S34.

In step S34, the detection unit 41 determines whether or not the amount of received infrared light detected by the infrared sensor 6 is equal to or less than a third water detection threshold. The detection unit 41 detects that water is present in the washbasin 410 when the amount of received infrared light detected by the infrared sensor 6 is equal to or less than the third water detection threshold, and detects that water is not present in the washbasin 410 when the amount of received infrared light detected by the infrared sensor 6 is greater than the third water detection threshold.

When the detection unit 41 determines in step S34 that the amount of received infrared light detected by the infrared sensor 6 is equal to or less than the third water detection threshold, the routine proceeds to step S35. In step S35, the detection unit 41 determines whether or not the amount of received infrared light detected by the infrared sensor 6 is equal to or greater than a third hand detection threshold. The detection unit 41 detects that a hand is present in the drying processing space 50 when the amount of received infrared light detected by the infrared sensor 6 is equal to or greater than the third hand detection threshold, and detects that no hand is present in the drying processing space 50 when the amount of received infrared light detected by the infrared sensor 6 is smaller than the third hand detection threshold.

When the detection unit 41 determines in step S35 that the amount of received infrared light detected by the infrared sensor 6 is equal to or greater than the third hand detection threshold, the process returns to step S35, and step S35 is repeated until the amount of received infrared light detected by the infrared sensor 6 is determined to be less than the third hand detection threshold. When the detection unit 41 determines in step S35 that the amount of received infrared light detected by the infrared sensor 6 is smaller than the third hand detection threshold, the routine proceeds to step S34. The operations of step S34 and step S35 are repeated until the detection unit 41 determines in step S34 that the amount of received infrared light detected by the infrared sensor 6 is greater than the third water detection threshold.

When the detection unit 41 determines in step S34 that the amount of received infrared light detected by the infrared sensor 6 is greater than the third water detection threshold, the process proceeds to step S36. In step S36, the detection unit 41 determines whether or not the amount of received infrared light detected by the infrared sensor 6 is equal to or greater than a third hand detection threshold.

When it is determined in step S36 that the received light amount of the infrared ray detected by the infrared ray sensor 6 is smaller than the third hand detection threshold, the process returns to step S33. When it is determined in step S36 that the amount of received infrared light detected by the infrared sensor 6 is equal to or greater than the third hand detection threshold, the routine proceeds to step S37, and the operation control unit 42 drives the blower 2 at the first air flow rate.

In step S38, the detection unit 41 determines whether or not the amount of received infrared light detected by the infrared sensor 6 is equal to or greater than a third hand detection threshold. When the detection unit 41 determines in step S38 that the amount of received infrared light detected by the infrared sensor 6 is equal to or greater than the third hand detection threshold, the process returns to step S38, and step S38 is repeated until the amount of received infrared light detected by the infrared sensor 6 is determined to be less than the third hand detection threshold.

When the detection unit 41 determines in step S38 that the amount of received infrared light detected by the infrared sensor 6 is smaller than the third hand detection threshold, the routine proceeds to step S39, and the operation control unit 42 stops the driving of the blower 2. When the drive of the blower 2 is stopped in step S39, the process proceeds to step S33.

Fig. 21 is a timing chart showing changes in the amount of infrared light detected by the infrared sensor 6 of the hand dryer 100 according to embodiment 5. In fig. 21, the third water detection threshold is indicated by a one-dot chain line, the third hand detection threshold is indicated by a broken line, and the amount of received infrared light detected by the infrared sensor 6 is indicated by a solid line. The time intervals at times T0, T1, T2, T3, T4, T5, T6, T8, T9, and T10 are update cycles of the third hand detection threshold and the third water detection threshold.

At time T1, the detection unit 41 updates the reference value, and further updates the third hand detection threshold and the third water detection threshold. At time T1a, water begins to accumulate within the lavatory 410. At time T1b, the amount of received infrared light detected by the infrared sensor 6 is equal to or less than the third water detection threshold, and the detection unit 41 detects that water is present in the washbasin 410. At times T2 and T3, the amount of infrared light detected by the infrared sensor 6 becomes equal to or less than the third water detection threshold, and the presence of water in the wash basin 410 is detected, so the detection unit 41 stops updating the third hand detection threshold and the third water detection threshold.

At time T3a, when the hand is disposed in the drying processing space 50, the amount of received infrared light detected by the infrared sensor 6 becomes equal to or greater than the third hand detection threshold, and the detection unit 41 detects that the hand is present in the drying processing space 50. In embodiment 5, at time T3a, the operation control unit 42 stops the driving of the blower 2 even if the detection unit 41 detects that there is a hand in the drying processing space 50. Further, at the time T3a, when the detection unit 41 detects that there is a hand in the drying processing space 50, the blower 2 may be driven at the second air flow rate smaller than the first air flow rate, as in the case of embodiment 2.

At times T4 and T5, the amount of infrared light detected by the infrared sensor 6 is equal to or less than the third water detection threshold, and the presence of water in the wash basin 410 is detected, so the detection unit 41 stops updating the third hand detection threshold and the third water detection threshold.

At time T5a, the water in the lavatory 410 begins to drain. At time T5b, when the amount of received infrared light detected by the infrared sensor 6 exceeds the third water detection threshold, the detection unit 41 detects that there is no water in the washbasin 410. At times T6 and T7, the detector 41 updates the reference value, and further updates the third hand detection threshold and the third water detection threshold.

At time 7a, when the hand is disposed in the drying processing space 50, the amount of received infrared light detected by the infrared sensor 6 becomes equal to or greater than the third hand detection threshold, and the detection unit 41 detects that the hand is present in the drying processing space 50. At time 7a, the operation control unit 42 drives the blower 2 at the first air flow rate because the detection unit 41 detects that there is no water in the washbasin 410 and that there is a hand in the drying processing space 50. At times T8, T9, and T10, the detector 41 updates the reference value, and further updates the third hand detection threshold and the third water detection threshold.

According to the hand drying device 100 of embodiment 5, the presence or absence of the hands in the drying processing space 50 and the presence or absence of the water in the washbasin 410 are detected by the single infrared sensor 6, so that it is not necessary to provide a sensor for detecting the presence or absence of the water in the washbasin 410 separately from the sensor for detecting the presence or absence of the hands. This enables realization of the hand drying device 100 having the hand detection function and the water detection function while suppressing an increase in cost. As described above, even if the infrared sensor 6 is used instead of the capacitance sensor 4, the effect of the present disclosure can be obtained by detecting the presence or absence of a hand and the presence or absence of water in the sink with one sensor.

The configuration described in the above embodiment is an example of the contents of the present disclosure, and may be combined with other known techniques, and a part of the configuration may be omitted or changed within a range not departing from the gist of the present disclosure.

Description of the reference numerals

2 blower, 3 nozzle, 3a blow-out port, 4 electrostatic capacity sensor, 4a first electrode, 4b second electrode, 5 screw, 6 infrared ray sensor, 10 box, 20 main body, 30 pipe, 31 ventilation path, 40 control part, 41 detection part, 42 operation control part, 50 drying processing space, 60 main body, 91 processor, 92 memory, 100 hand drying device, 200 water discharge device, 210 water discharge pipe, 211 water discharge port, 300 detergent discharge device, 310 detergent discharge pipe, 311 detergent discharge port, 400 washbasin, 401-404 through hole, 410 washbasin, 411 discharge port, 500 wall, 501 floor, 600 drain pipe.

Claims

1. A hand drying device, comprising:

a nozzle that blows an air flow toward a drying processing space where a hand is dried;

a blower that generates the air flow;

an electrostatic capacitance sensor which has two electrodes and detects an electrostatic capacitance between the two electrodes;

a detection unit that detects that water is present in the sink that receives the air flow when the capacitance detected by the capacitance sensor is equal to or greater than a first water detection threshold value, and that detects that a hand is present in the drying processing space when the capacitance detected by the capacitance sensor is equal to or less than a first hand detection threshold value that is smaller than the first water detection threshold value; and

and an operation control unit that controls an operation of the blower based on a detection result of the detection unit.

2. The hand drying apparatus of claim 1,

the detection unit detects that a hand is present in the drying processing space when the capacitance detected by the capacitance sensor is equal to or less than a second hand detection threshold value that is greater than the first hand detection threshold value, when the presence of water in the sink is detected.

3. The hand drying apparatus of claim 2,

the detection unit updates the first water detection threshold, the first hand detection threshold, and the second hand detection threshold when a preset setting time has elapsed after the first water detection threshold, the first hand detection threshold, and the second hand detection threshold are set.

4. The hand drying apparatus of claim 3,

the detection unit stops updating of the first water detection threshold, the first hand detection threshold, and the second hand detection threshold when it is detected that water is present in the sink and when it is detected that a hand is present in the drying processing space.

5. The hand drying apparatus according to any one of claims 1 to 4,

the operation control unit stops the driving of the blower when the detection unit detects that water is present in the sink.

6. The hand drying apparatus according to any one of claims 1 to 4,

the operation control unit drives the blower with a first air volume when the detection unit detects that there is no water in the sink and that the drying processing space has a hand, and drives the blower with a second air volume smaller than the first air volume when the detection unit detects that there is water in the sink and that the drying processing space has a hand.

7. The hand drying apparatus of claim 6,

the detection unit detects that the sink is full of water when the capacitance detected by the capacitance sensor is equal to or greater than a second water detection threshold that is greater than the first water detection threshold,

the operation control unit stops the driving of the blower when the detection unit detects that the wash basin is full of water.

8. A hand drying device, comprising:

a blower that generates the air flow;

an infrared sensor that includes an infrared light emitting element that emits infrared light and an infrared light receiving element that receives the infrared light, and that detects an amount of infrared light received by the infrared light receiving element;

a detection unit that detects that water is present in the sink that receives the air flow when the amount of light received by the infrared sensor is equal to or less than a third water detection threshold, and that detects that a hand is present in the drying processing space when the amount of light received by the infrared sensor is equal to or more than a third hand detection threshold that is greater than the third water detection threshold; and