WO2017145387A1

WO2017145387A1 - Refrigerator

Info

Publication number: WO2017145387A1
Application number: PCT/JP2016/055924
Authority: WO
Inventors: 桂佑長野
Original assignee: 三菱電機株式会社
Priority date: 2016-02-26
Filing date: 2016-02-26
Publication date: 2017-08-31
Also published as: JPWO2017145387A1; JP6516915B2

Abstract

The refrigerator 1 is equipped with: a refrigerating compartment 2a; a door 5a which opens and closes the opening of the refrigerating compartment 2a; a door switch 6a which detects the open or closed state of the door 5a; an ultrasonic sensor 8 which is provided on the door 5a; a vegetable compartment 2e which is disposed below the refrigerating compartment 2a; a door 5e which opens and closes the opening of the vegetable compartment 2e; a door switch 6e which detects the open or closed state of the door 5e; an ultrasonic sensor 9 which is provided on the door 5e; and a microcomputer 26 which is capable of determining that the doors 5a, 5e are left open. If the open state of the door 5a is maintained for a certain time period or more, the microcomputer 26 determines the presence or absence of a person in front of the refrigerator 1 using the ultrasonic sensor 8, and sounds an alarm 10 only when there is no person in front of the refrigerator 1. If the open state of the door 5e is maintained for a certain time period or more, the microcomputer 26 determines the presence or absence of a person in front of the refrigerator 1 using the ultrasonic sensor 9, and sounds the alarm 10 only when there is nobody in front of the refrigerator 1.

Description

refrigerator

This invention relates to the refrigerator which can alert | report the forgetting to close the door of a storage room.

Conventionally, there is a known refrigerator that notifies the user of forgetting to close the storage room door using an alarm sound. According to such a refrigerator, an alarm may sound during storage of storage items in the storage room or removal of storage items from the storage chamber, which may cause annoyance to the user. .

Patent Document 1 describes a refrigerator provided with means that can change an alarm to an off setting.

JP 2011-158234 A

However, according to the refrigerator described in Patent Document 1, when the alarm is changed to the off setting, the alarm does not sound when the door is actually forgotten to be closed, and it is difficult to suppress the forgetting to close the door. It becomes.

The present invention has been made in view of the above, and the alarm is not sounded during the storage of the storage item in the storage chamber or the removal of the storage item from the storage chamber, and the door is forgotten to be closed. The aim is to provide a refrigerator that sometimes sounds an alarm.

In order to solve the above-described problems and achieve the object, a refrigerator according to the present invention is a refrigerator including an alarm that generates an alarm sound, and includes a first storage chamber and an opening of the first storage chamber. A first door that opens and closes the first door, first door open / close detection means that detects an open / closed state of the first door, a first human sensor provided on the first door, and the first A second storage chamber disposed below the storage chamber, a second door for opening and closing the opening of the second storage chamber, and a second door for detecting the open / closed state of the second door When the open / close detection means, the second human sensor provided on the second door, and the first door open state continues for a predetermined time or longer, the second human sensor is used. The presence or absence of a person in front of the refrigerator is determined, the alarm is sounded only when there is no person in front of the refrigerator, and the second door is opened. Is continued for the predetermined time or more, the presence or absence of a person in front of the refrigerator is determined using the first human sensor, and the alarm is sounded only when there is no person in front of the refrigerator; It is characterized by providing.

According to the present invention, there is provided a refrigerator in which an alarm does not sound during storage of a stored item in a storage room or during removal of a stored item from the storage room, and an alarm sounds when the door is forgotten to be closed. There is an effect that it is possible.

Front view of the refrigerator according to the first embodiment AA sectional view in FIG. Control block diagram in the first embodiment 2 is a diagram illustrating an example of a hardware configuration of a microcomputer according to Embodiment 1. FIG. Control flowchart in Embodiment 1 Front view of the refrigerator according to the second embodiment BB sectional view in FIG. Control block diagram in the second embodiment Control flowchart in Embodiment 2

Hereinafter, a refrigerator according to an embodiment of the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment 1 FIG.
FIG. 1 is a front view of the refrigerator according to the present embodiment, and FIG. 2 is a cross-sectional view taken along the line AA in FIG.

The refrigerator 1 includes a box 3 provided with a plurality of storage rooms 2 partitioned from each other. Here, the plurality of storage chambers 2 are a refrigerator compartment 2a capable of storing stored items, an ice making chamber 2b capable of manufacturing and storing ice, a switching chamber 2c capable of switching temperature, and a freezer chamber capable of storing stored items in a frozen state. 2d and a vegetable room 2e capable of storing vegetables. The stored items are usually food. The refrigerator 1 is a refrigerator-freezer.

The refrigerator compartment 2 a is provided above the other storage compartment 2. An opening 4a is provided on the front surface of the refrigerator compartment 2a. The refrigerator 1 includes a pair of double doors 5a that can open and close the opening 4a. The refrigerator 1 includes a door switch 6a that can detect the open / closed state of the pair of doors 5a. The door switch 6a is turned on or off according to the open / closed state of the pair of doors 5a, and outputs a signal according to the open / closed state of the pair of doors 5a.

The ice making room 2b is provided under the refrigerator compartment 2a. An opening 4b is provided on the front surface of the ice making chamber 2b. The refrigerator 1 includes a drawer-type door 5b that can open and close the opening 4b. The refrigerator 1 includes a door switch 6b that can detect the open / closed state of the door 5b. The door switch 6b is turned on or off according to the open / closed state of the door 5b, and outputs a signal according to the open / closed state of the door 5b.

The switching room 2c is provided under the refrigerator compartment 2a. The switching chamber 2c is arranged at the same height as the ice making chamber 2b. An opening 4c is provided on the front surface of the switching chamber 2c. The refrigerator 1 includes a drawer-type door 5c that can open and close the opening 4c. The refrigerator 1 includes a door switch 6c that can detect the open / closed state of the door 5c. The door switch 6c is turned on or off according to the open / closed state of the door 5c, and outputs a signal according to the open / closed state of the door 5c.

The freezing room 2d is provided under the ice making room 2b and the switching room 2c. An opening 4d is provided on the front surface of the freezer compartment 2d. The refrigerator 1 includes a drawer-type door 5d that can open and close the opening 4d. The refrigerator 1 includes a door switch 6d that can detect the open / closed state of the door 5d. The door switch 6d is turned on or off according to the open / closed state of the door 5d, and outputs a signal according to the open / closed state of the door 5d.

The vegetable room 2e is provided under the freezer room 2d. An opening 4e is provided on the front surface of the vegetable compartment 2e. The refrigerator 1 includes a drawer-type door 5e that can open and close the opening 4e. The refrigerator 1 includes a door switch 6e that can detect the open / closed state of the door 5e. The door switch 6e is turned on or off according to the open / closed state of the door 5e, and outputs a signal according to the open / closed state of the door 5e.

The refrigerator compartment 2a is a first storage room, the pair of doors 5a is a first door, and the door switch 6a is a first door opening / closing detection means. The vegetable compartment 2e is a second storage room, the door 5e is a second door, and the door switch 6e is a second door opening / closing detection means. The ice making chamber 2b, the switching chamber 2c, and the freezing chamber 2d are third storage chambers, doors 5b to 5d are third doors, and door switches 6b to 6d are third door opening / closing detection means.

In the following, when the doors 5a to 5e are not distinguished, each of the doors 5a to 5e is represented by the door 5. When the openings 4a to 4e are not distinguished, each of the openings 4a to 4e is represented by the opening 4. Furthermore, when the door switches 6a to 6e are not distinguished, each of the door switches 6a to 6e is represented by the door switch 6.

The refrigerator 1 includes an operation panel 7. The operation panel 7 is provided on the door 5a. The operation panel 7 receives the setting of the refrigerator 1.

The refrigerator 1 includes

ultrasonic sensors

8 and 9. Here, the ultrasonic sensor 8 is provided on the outer surface of the door 5a, and the ultrasonic sensor 9 is provided on the outer surface of the door 5e. That is, the ultrasonic sensor 8 is disposed above the ultrasonic sensor 9. The ultrasonic sensor 8 generates an ultrasonic wave, transmits an ultrasonic transmission wave, and receives a reflected wave with respect to the ultrasonic transmission wave. The ultrasonic sensor 8 measures the distance to the reflector based on the time from transmission wave transmission to reception wave reception.

The ultrasonic sensor 8 can determine the presence or absence of a person in front of the refrigerator 1 based on the measured distance. The ultrasonic sensor 9 is the same as the ultrasonic sensor 8. The

ultrasonic sensors

8 and 9 can each be configured using a piezoelectric ceramic. The ultrasonic sensor 8 is a first human sensor, and the ultrasonic sensor 9 is a second human sensor.

The refrigerator 1 includes an alarm 10. The alarm 10 generates an alarm sound. The alarm 10 is an informing means for informing that the door 5 is in an open state with an alarm sound. The alarm sound includes sound. The alarm 10 is provided on the front side of the upper surface of the refrigerator 1. The alarm 10 generates an alarm sound only when it is determined that the door 5 is in a state where it is forgotten to close.

The refrigerator 1 includes a control board 25. The control board 25 is provided on the back side of the upper surface of the refrigerator 1.

Here, the internal configuration of the refrigerator 1 will be briefly described. An air passage 15 is provided in the box 3. The air passage 15 is provided on the back side of the refrigerator 1. The air path 15 connects the freezer compartment 2d and the refrigerator compartment 2a. A cooler 16 that generates cool air and a fan 17 that circulates the cool air are provided in the air passage 15. The refrigerator 1 includes a compressor 19 in a machine room 18 provided on the back side of the refrigerator 1. The compressor 19 and the cooler 16 are part of the components of the refrigeration cycle. Illustration of other components of the refrigeration cycle is omitted.

When the compressor 19 is driven, the refrigerant circulates in the refrigeration cycle. In the cooler 16, the ambient air and the refrigerant exchange heat, and the air is cooled to generate cold air. This cold air is circulated in the box 3 through the air passage 15 by the rotation of the fan 17 and further through the refrigerator compartment 2a, the return passage 20, the ice making compartment 2b, the switching compartment 2c, the freezer compartment 2d, and the vegetable compartment 2e. To do. Note that the amount of cool air flowing into the storage chamber 2 is adjusted by the damper 21. The cooling function of the refrigerator 1 is adjusted by changing the rotation speed of the compressor 19 and the rotation speed of the fan 17.

FIG. 3 is a control block diagram in the present embodiment. The control board 25 is a board provided with a control circuit, and includes a microcomputer 26 and a clock 27. The microcomputer 26 is a control unit that controls the refrigerator 1. The clock 27 outputs time information to the microcomputer 26.

The door switch 6a outputs a signal indicating the open / closed state of the door 5a of the refrigerator compartment 2a to the microcomputer 26. The door switch 6b outputs a signal indicating the open / closed state of the door 5b of the ice making chamber 2b to the microcomputer 26. The door switch 6c outputs a signal indicating the open / closed state of the door 5c of the switching chamber 2c to the microcomputer 26. The door switch 6d outputs a signal indicating the open / closed state of the door 5d of the freezer compartment 2d to the microcomputer 26. The door switch 6e outputs a signal indicating the open / closed state of the door 5e of the vegetable compartment 2e to the microcomputer 26.

The ultrasonic sensor 8 outputs a signal indicating whether or not there is a person in front of the refrigerator 1 to the microcomputer 26. The ultrasonic sensor 9 outputs a signal indicating the presence / absence of a person in front of the refrigerator 1 to the microcomputer 26.

The microcomputer 26 controls the alarm 10 based on the outputs of the door switches 6a to 6e, the outputs of the

ultrasonic sensors

8 and 9, and the output of the clock 27. That is, when the microcomputer 26 determines that the door 5 of the storage chamber 2 is in a state where it has been forgotten to close, the alarm 10 is sounded, and in other cases, the alarm 10 is not sounded. A method for determining whether or not the door 5 is in the state of forgetting to close will be described later.

FIG. 4 is a diagram showing an example of the hardware configuration of the microcomputer 26. As shown in FIG. The microcomputer 26 includes a processor 26a and a memory 26b. The processor 26a executes a program stored in the memory 26b and executes a control method described in the program. The processor 26a is, for example, a CPU, and the memory 26b is, for example, a semiconductor memory.

FIG. 5 is a control flowchart in the present embodiment. First, in S <b> 1, the microcomputer 26 detects the output of the door switch 6.

Next, in S2, the microcomputer 26 determines whether or not the door 5 of the storage chamber 2 is in an open state based on the output of the door switch 6. As a result of this determination, if the door 5 is in the closed state, the microcomputer 26 returns to the process of S1. If the result of this determination is that the door 5 is open, the microcomputer 26 proceeds to the processing of S3 and starts measuring the time during which the door 5 is open.

Next, after detecting the output of the door switch 6 in S4, the microcomputer 26 determines whether or not the door 5 of the storage chamber 2 is closed based on the output of the door switch 6 in S5. To do. As a result of this determination, if the door 5 is in the closed state, the microcomputer 26 returns to the process of S1. If the result of this determination is that the door 5 is in the open state, the microcomputer 26 proceeds to the process of S6.

In S6, the microcomputer 26 determines whether the open state of the door 5 has continued for T seconds or more. Here, T is a predetermined time. If the result of this determination is that the door 5 has not been opened for more than T seconds, the microcomputer 26 returns to S4. If the result of this determination is that the door 5 is open for at least T seconds, the microcomputer 26 proceeds to S7.

Next, in S7, the microcomputer 26 determines whether or not the door 5 is the door 5a of the refrigerator compartment 2a. If the result of this determination is that the door 5 is the door 5a, the microcomputer 26 detects the output of the ultrasonic sensor 9 at S8 and uses the output of the ultrasonic sensor 9 at S10 to Determine the presence of the previous person. As a result of the determination, if the door 5 is not the door 5a, that is, if the door 5 is one of the doors 5b to 5e, the microcomputer 26 detects the output of the ultrasonic sensor 8 in S9, In S10, the presence or absence of a person in front of the refrigerator 1 is determined using the output of the ultrasonic sensor 8.

If the result of determination in S10 is that there is no person in front of the refrigerator 1, the microcomputer 26 determines that the door 5 has been forgotten to close and outputs a control signal to the alarm 10, and in S11, the alarm 10 Sound. If there is a person in front of the refrigerator 1 as a result of the determination in S10, the microcomputer 26 determines that the stored item is being stored in the storage chamber 2 or being extracted from the storage chamber 2. The process returns to S1 without sounding the alarm 10.

The microcomputer 26 monitors the outputs of the door switches 6a to 6e and performs the above-described control process on the doors 5a to 5e.

According to the present embodiment, the alarm 10 is not sounded during storage of the storage item in the storage chamber 2 or removal of the storage item from the storage chamber 2, and the alarm is generated when the door 5 is forgotten to be closed. 10 sounds.

In other words, according to the present embodiment, the alarm 10 does not sound while the stored item is being stored in the refrigerator 1 or while the stored item is being taken out from the refrigerator 1, and the user can hear the alarm sound while using the refrigerator 1. There is no annoyance. Furthermore, according to the present embodiment, when a certain period of time has passed after a person leaves the refrigerator 1 while the door 5 is open, an alarm 10 sounds and the door 5 is open. Therefore, it is possible to suppress forgetting to close the door 5.

In this Embodiment, when the door 5a of the refrigerator compartment 2a arrange | positioned at the upper part of the refrigerator 1 is open, the microcomputer 26 is the super provided in the door 5e of the vegetable compartment 2e provided in the lower part of the refrigerator 1. The presence of a person in front of the refrigerator 1 is determined using the sonic sensor 9. Further, in the present embodiment, at least one of the door 5b of the ice making chamber 2b, the door 5c of the switching chamber 2c, the door 5d of the freezing chamber 2d, and the door 5e of the vegetable chamber 2e disposed below the refrigerator compartment 2a. When one of them is open, the microcomputer 26 determines the presence or absence of a person in front of the refrigerator 1 using the ultrasonic sensor 8 provided on the door 5a of the refrigerator compartment 2a provided on the top of the refrigerator 1. Thus, the reliability of the detection of the presence or absence of the person in front of the refrigerator 1 increases by providing the two

ultrasonic sensors

8 and 9.

Note that the arrangement, number and type of the plurality of storage chambers 2 are not limited to the illustrated example. The number of the storage chambers 2 should just be two or more.

Moreover, although the ultrasonic sensor 9 is provided in the door 5e of the vegetable compartment 2e, the structure provided in the door 5b of the ice making chamber 2b, the door 5c of the switching chamber 2c, or the door 5d of the freezer compartment 2d is also possible.

Further, the human sensor for determining the presence or absence of a person in front of the refrigerator 1 is not limited to the

ultrasonic sensors

8 and 9 but may be a sensor using electromagnetic waves, for example, an infrared sensor.

In the present embodiment, the alarm sound is used to notify that the door 5 is open, but the present invention is not limited to this, and the alarm display may notify that the door 5 is open.

In addition, although the pair of doors 5a is of the double door type, it is not limited to this opening / closing method, and the doors 5b to 5e are of the pulling type, but are not limited to this opening / closing method.

Embodiment 2. FIG.
6 is a front view of the refrigerator according to the present embodiment, and FIG. 7 is a cross-sectional view taken along the line BB in FIG. 6 and 7, the same components as those shown in FIGS. 1 and 2 are denoted by the same reference numerals.

The refrigerator 1a according to the present embodiment is different from the refrigerator 1 of the first embodiment in the following points. That is, the refrigerator 1a according to the present embodiment includes the ultrasonic sensor 30 in the vegetable compartment 2e instead of including the

ultrasonic sensors

8 and 9 of the first embodiment. In other respects, the configuration of the refrigerator 1 a is the same as the configuration of the refrigerator 1.

The ultrasonic sensor 30 is installed, for example, on the front surface of a storage case (not shown) in the vegetable compartment 2e. The ultrasonic sensor 30 generates an ultrasonic wave, transmits an ultrasonic transmission wave, and receives a reflected wave with respect to the ultrasonic transmission wave. The ultrasonic sensor 30 measures the distance to the reflector based on the time from transmission wave transmission to reception wave reception.

The ultrasonic sensor 30 can determine the presence or absence of movement of stored items in the vegetable compartment 2e based on the measured distance. That is, the ultrasonic sensor 30 detects the movement of the stored item when the door 5e of the vegetable chamber 2e is opened and the stored item is moving in the vegetable chamber 2e while the stored item is being stored or taken out. The ultrasonic sensor 30 can be configured using a piezoelectric ceramic. The ultrasonic sensor 30 is a movement detection sensor that detects movement of stored items in the vegetable compartment 2e.

FIG. 8 is a control block diagram in the present embodiment. The door switch 6e outputs a signal indicating the open / closed state of the door 5e of the vegetable compartment 2e to the microcomputer 26. The ultrasonic sensor 30 outputs a signal indicating whether or not the stored item has moved in the vegetable compartment 2e to the microcomputer 26.

The microcomputer 26 controls the alarm 10 based on the output of the door switch 6e, the output of the ultrasonic sensor 30, and the output of the clock 27. That is, when the microcomputer 26 determines that the door 5e of the vegetable compartment 2e is in a state where it has been forgotten to close, the microcomputer 10 sounds the alarm 10, and otherwise does not sound the alarm 10.

FIG. 9 is a control flowchart in the present embodiment. First, in S21, the microcomputer 26 detects the output of the door switch 6e.

Next, in S22, the microcomputer 26 determines whether or not the door 5e of the vegetable compartment 2e is open based on the output of the door switch 6e. If the result of this determination is that the door 5e is closed, the microcomputer 26 returns to the processing of S21. If the result of this determination is that the door 5e is in the open state, the microcomputer 26 proceeds to the processing of S23.

In S23, the microcomputer 26 detects the output of the ultrasonic sensor 30, and uses the output of the ultrasonic sensor 30 to determine whether the stored item has moved in the vegetable compartment 2e. As a result of this determination, if the stored item is moving in the vegetable compartment 2e, the microcomputer 26 returns to the process of S21. If the result of this determination is that the stored item is not moving in the vegetable compartment 2e, the microcomputer 26 proceeds to the processing of S24 and starts measuring the time during which the door 5e is open.

Next, the microcomputer 26 detects the output of the door switch 6e in S25, and determines whether or not the door 5e of the vegetable compartment 2e is closed based on the output of the door switch 6e in S26. . As a result of this determination, if the door 5e is in the closed state, the microcomputer 26 returns to the process of S21. If the result of this determination is that the door 5e is in the open state, the microcomputer 26 determines in S27 whether or not the open state of the door 5e has continued for at least T seconds. Here, T is a predetermined time.

If the result of determination in S27 is that the door 5e has not been opened for more than T seconds, the microcomputer 26 returns to S25. If the result of determination in S27 is that the door 5e has been open for more than T seconds, the microcomputer 26 determines that the door 5e has been forgotten to close and the control signal is sent to the alarm 10 in S28. Is output and the alarm 10 is sounded.

As described above, according to the present embodiment, since the ultrasonic sensor 30 detects the movement of the stored item in the vegetable compartment 2e, the stored item is being stored in the refrigerator 1 by the user. Or it can suppress that the alarm 10 rings during taking-out of the stored item from the refrigerator 1. FIG.

In this embodiment, the ultrasonic sensor 30 is provided in the vegetable compartment 2e, and the alarm 10 sounds when the door 5e of the vegetable compartment 2e is forgotten to be closed, but is not limited thereto. That is, the ultrasonic sensor 30 is provided in at least one storage chamber 2 among the refrigerator compartment 2a, the ice making chamber 2b, the switching chamber 2c, the freezing chamber 2d, and the vegetable chamber 2e, and the storage chamber 2 provided with the ultrasonic sensor 30. An alarm 10 may sound when the door 5 is forgotten to be closed.

In addition, the vegetable compartment 2e generally has no partition and has a simple indoor structure. Therefore, the detection of the movement of the stored item in the vegetable compartment 2e can be performed by one ultrasonic sensor 30. The same applies to the ice making chamber 2b, the switching chamber 2c, and the freezing chamber 2d.

In the present embodiment, the case where the ultrasonic sensor 30 is used as the movement detection sensor has been described. However, the present invention is not limited to this, and the movement detection sensor may be a sensor using electromagnetic waves, for example, an infrared sensor.

The configuration described in the above embodiment shows an example of the contents of the present invention, and can be combined with another known technique, and can be combined with other configurations without departing from the gist of the present invention. It is also possible to omit or change the part.

1, 1a refrigerator, 2 storage room, 2a cold storage room, 2b ice making room, 2c switching room, 2d freezing room, 2e vegetable room, 3 box, 4, 4a-4e opening, 5, 5a-5e door, 6, 6a to 6e door switch, 7 operation panel, 8, 9, 30 ultrasonic sensor, 10 alarm, 15 air path, 16 cooler, 17 fan, 18 machine room, 19 compressor, 20 return path, 21 damper, 25 control Board, 26 microcomputer, 26a processor, 26b memory, 27 clocks.

Claims

A refrigerator equipped with an alarm that generates an alarm sound,
A first storage room;
A first door for opening and closing the opening of the first storage chamber;
First door opening / closing detection means for detecting an opening / closing state of the first door;
A first human sensor provided on the first door;
A second storage chamber disposed below the first storage chamber;
A second door for opening and closing the opening of the second storage chamber;
Second door opening / closing detection means for detecting the opening / closing state of the second door;
A second human sensor provided on the second door;
When the open state of the first door continues for a certain time or more, the presence or absence of a person in front of the refrigerator is determined using the second human sensor, and only when there is no person in front of the refrigerator When an alarm is sounded and the open state of the second door continues for the predetermined time or longer, the presence or absence of a person in front of the refrigerator is determined using the first human sensor, and a person in front of the refrigerator And a control unit that sounds the alarm only when there is not.
A third storage chamber disposed below the first storage chamber and above the second storage chamber;
A third door for opening and closing the opening of the third storage chamber;
Third door opening / closing detection means for detecting an open / closed state of the third door;
With
The controller determines whether or not there is a person in front of the refrigerator using the first human sensor when the open state of the third door continues for the predetermined time or more, and the person in front of the refrigerator The refrigerator according to claim 1, wherein the alarm is sounded only when there is no sound.
The refrigerator according to claim 1 or 2, wherein each of the first and second human sensors is an ultrasonic sensor.
A refrigerator equipped with an alarm that generates an alarm sound,
A storage room;
A door for opening and closing the opening of the storage chamber;
Door opening / closing detection means for detecting the opening / closing state of the door;
A movement detection sensor provided in the storage chamber for detecting movement of stored items in the storage chamber;
When it is detected by the door opening / closing detection means that the door is in an open state, the movement detection sensor is used to determine whether or not the stored item has moved in the storage chamber. And a controller that sounds the alarm only when there is no movement of the stored item and the open state of the door continues for a certain period of time.
The refrigerator according to claim 4, wherein the movement detection sensor is an ultrasonic sensor.