Air conditioner

Abstract

To provide an air conditioner which discriminates humans from heat sources other than humans and inhibits air conditioning control to the heat sources other than humans.SOLUTION: An air conditioner 1 includes: an indoor unit 3 which sends air from an air outlet with a blower fan 7 which can vary an air volume; a remote controller 30 which operates the indoor unit; a control unit 10 which controls the indoor unit; and an infrared sensor 15 which rotationally scan to detect a temperature distribution in an indoor space in which the indoor unit is installed. The control unit selects first temperature acquisition means which causes the infrared sensor to rotationally scan at a predetermined first step angle to acquire position information of a heat source in the indoor space or second temperature control means which causes the infrared sensor to rotationally scan at a second step angle smaller than the first step angle to acquire position information of a human in the indoor space. When operation of the indoor unit starts, the second temperature acquisition means is performed.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an air conditioner. [Background technology]

[0002] For example, Patent Document 1 describes an air conditioner that operates a thermal sensor (thermopile sensor) in a first mode that detects a person's thermal sensation with high resolution and a second mode that detects the amount of activity of the person, and switches between these modes depending on the fan rotation speed and room temperature. Note that when the fan rotation speed is equal to or lower than a predetermined number of rotations, detection in the first mode is not performed and the second mode is performed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-074288 Summary of the Invention [Problem to be solved by the invention]

[0004] If the fan speed is below a predetermined value during heating operation, the air conditioner of Patent Document 1 operates in a second mode that detects the amount of human activity. However, if there is a heat source in the room, such as another heater or a rise in floor temperature due to sunlight, the temperature sensor (thermopile sensor) does not detect with high accuracy, and there is a risk of making an erroneous judgment because it cannot distinguish between a human and a non-human heat source. [Means for solving the problem]

[0005] In order to solve the above problem, the air conditioner of claim 1 of the present invention comprises an indoor unit that draws in indoor air through an intake port and then blows it out through an outlet port using a variable air volume blower fan, a remote control that operates the indoor unit, a control unit that controls the air conditioning of the indoor unit in accordance with instructions from the remote control, and an infrared sensor that detects the temperature distribution in the room in which the indoor unit is installed by rotating and scanning, and the control unit selects between a first temperature acquisition means that rotates and scans the infrared sensor at a predetermined first step angle to acquire position information of heat sources in the room, and a second temperature acquisition means that rotates and scans the infrared sensor at a second step angle smaller than the first step angle to acquire position information of people in the room, and is characterized in that the second temperature acquisition means is executed when operation of the indoor unit starts.

[0006] In addition, in the air conditioner of claim 2, the control unit is characterized in that when the second temperature acquisition means is executed, it determines whether the object is a person or something other than a person based on the acquisition result acquired by the second temperature acquisition means.

[0007] In the air conditioner according to claim 3, the control unit executes the first temperature acquisition means after executing the second temperature acquisition means for a predetermined time.

[0008] In addition, in the air conditioner of claim 4, when the first temperature acquisition means is executed, the control unit performs air conditioning control based on the position information of the person in the room, based on the result of determining whether the person is a person or something other than a person obtained by the second temperature acquisition means, while not reflecting temperature changes in the position information of heat sources other than the person in the air conditioning control. [Effects of the Invention]

[0009] According to this invention, by accurately detecting the location information of heat sources in the room using an infrared sensor when operation starts and distinguishing between human and non-human heat sources, it is possible to prevent erroneous determination of non-human heat sources as humans when air conditioning control is performed by obtaining human location information. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 10 is a diagram showing the detection angle range in the vertical direction of an infrared sensor according to an embodiment of the present invention. [Figure 2] FIG. 4 is a diagram showing a horizontal detection angle range of the infrared sensor in the embodiment; [Figure 3] FIG. 2 is a diagram showing an arrangement of pixel portions of the infrared sensor in the embodiment; [Figure 4] FIG. 2 is a diagram showing a thermal image acquired by an infrared sensor in the embodiment; [Figure 5] FIG. 10 is a diagram showing a temperature distribution acquired by an infrared sensor in the embodiment; [Figure 6] FIG. 2 is a control block diagram of the air conditioner according to the embodiment; DETAILED DESCRIPTION OF THE INVENTION

[0011] Next, an air conditioner according to an embodiment of the present invention will be described with reference to the drawings.

[0012] In the following description, "front (front face)," "rear (rear face)," "upper," "lower," "right," and "left" follow the definitions in Figures 1 to 3. The up-down direction corresponds to the vertical direction when the air conditioner 1 is installed. The front-rear direction and the left-right direction correspond to the horizontal direction when the air conditioner 1 is installed.

[0013] The air conditioner 1 comprises an indoor unit 3 installed indoors and an outdoor unit 11 installed outdoors. The indoor unit 3 is installed horizontally on a wall near the ceiling inside the room and has an air inlet 4 on the top that draws in indoor air and an air outlet 5 that blows out temperature-controlled air from the bottom to the front. The indoor unit 3 also has an indoor blower fan 7 that takes in air from the room and blows it into the room, and an indoor heat exchanger 6 that cools or heats the air taken in by the indoor blower fan 7. The air conditioner 1 performs heating operation, in which the indoor air is heated by heating the intake air in the indoor heat exchanger 6 to heat the indoor air, and cooling operation, in which the indoor air is cooled by cooling the intake air.

[0014] An air flow path is formed by connecting the air inlet 4 with the indoor heat exchanger 6, the indoor blower fan 7, and the air outlet 5. For example, during heating operation, the indoor air drawn in through the air inlet 4 is heated by the indoor heat exchanger 6 and blown out downward through the air outlet 5, thereby raising the room temperature and circulating the air within the room. A room temperature sensor 8 is provided in the air flow path downstream of the air inlet 4 to detect the temperature of the drawn-in indoor air. The air outlet 5 is equipped with an up-down louver 18 that sets the vertical direction of the blown air and closes the air outlet 5 when operation is stopped, and a left-right louver 19 that sets the horizontal direction of the blown air. Reference numeral 10 denotes a control unit provided in the indoor unit 3, which controls the air conditioning of the air conditioner 1, particularly the indoor unit 3.

[0015] The indoor unit 3 and outdoor unit 11 are connected by a connecting pipe 12 through which the refrigerant circulates and a connecting wire 13 that transmits signals from the control unit 10. The outdoor unit 11 contains a compressor (not shown) and an outdoor heat exchanger (not shown) that are connected to the indoor heat exchanger 6 by a refrigerant pipe, and by operating a so-called heat pump cycle, the indoor heat exchanger 6 is heated by heat absorbed from the outdoor air, thereby heating the room.

[0016] The heater 2 is a type of heater that has traditionally been commonly used in homes, such as a kerosene stove, kerosene fan heater, or gas fan heater. The heater 2 is placed near the floor below the indoor unit 3, and has a combustion burner 22 and a heating fan 23 inside, burning fuel such as kerosene or gas in the combustion burner 22 and blowing air with the heating fan 23 to directly heat the room. The heater 2 is inexpensive, has low fuel costs, and can be moved to any room or place that requires heating, so it is often chosen as the main heater, and its relationship with the air conditioner 1 can also be selected according to the user's preferences.

[0017] FIG. 3 shows a control block diagram of the air conditioner 1. Reference numeral 30 denotes a remote control connected to the air conditioner 1 via a wired or wireless connection. The transmitter / receiver unit 31 of the remote control 30 and the transmitter / receiver unit 14 of the air conditioner 1 communicate with each other via a wireless communication line, such as infrared. The remote control 30 includes an operation unit 32 for performing various operations on the air conditioner 1 and a display unit 33 for displaying the settings of the air conditioner 1. The operation unit 32 includes an operation switch 34 that starts operation of the air conditioner 1 when pressed, a temperature setting switch 36 that sets the user's desired room temperature, and an operation mode switch 37 that selects an operation mode, such as heating operation, cooling operation, dehumidification operation, or automatic operation, which automatically sets the output of the outdoor unit 11 and the indoor fan 7 according to the room temperature. The display unit 33 has an LCD panel that allows the user to visually confirm the set room temperature and whether an operation mode, such as heating or cooling, is selected. The control unit 10 controls the air conditioning of the indoor unit 3 according to the instructions entered by the user through the remote control 30.

[0018] Reference numeral 15 denotes a non-contact infrared sensor that is installed inside the indoor unit 3 and detects the temperature distribution in the room. The infrared sensor 15 is, for example, a thermopile sensor, and has a multi-pixel structure in which multiple sensor elements, which are thermal detection elements, are integrated. The infrared sensor 15 can detect temperature changes and movement of an object, and therefore can detect the temperature and position, i.e., the temperature distribution, of a person 100, an object (for example, electrical equipment such as the heater 2), air (airflow), etc., inside the room. In the present embodiment, the infrared sensor 15 has a pixel section 16 arranged in a horizontal and vertical direction of 1×8 pixels, as shown in Fig. 4. However, the present invention is not limited to this, and the pixel section 16 may also be arranged in a 4×4 pixel or 8×8 pixel array.

[0019] The control unit 10 includes a temperature acquisition unit 42 that drives the infrared sensor driver 17 to rotate and scan the infrared sensor 15 around the vertical axis of rotation, thereby acquiring the temperature distribution in the room. The infrared sensor driver 17 is, for example, a stepping motor, and is driven at a predetermined step angle around the rotation axis (not shown). The dotted lines in FIG. 2 indicate the horizontal detection angle range of the infrared sensor 15 when viewed from above. The angle indicated by adjacent dotted lines is the field of view (single detection angle range) that can be acquired by one pixel, which is 5°. Therefore, the control unit 10 rotates and scans the infrared sensor driver 17 at a first step angle of 5° and adds up the obtained temperature distributions, thereby acquiring a wide horizontal temperature distribution. In FIG. 2, the infrared sensor driver 17 rotates and scans over a range of 150° to acquire the temperature distribution in the room. In other words, by rotating and scanning the infrared sensor 15 150° from one end of the dotted line in FIG. 2 to the other end, the temperature distribution in almost all areas of the room can be acquired. 1 indicates the vertical detection angle range of infrared sensor 15 when viewed in cross section, and the angle indicated by adjacent dotted lines is the viewing angle that can be acquired by one pixel (detection angle range of one pixel), which is 7°. Therefore, by adding up the temperature distributions obtained by each of pixels P1 to P8 of pixel unit 16, control unit 10 can obtain the indoor temperature distribution over a vertical range of 56°.

[0020] The control unit 10 also includes a memory unit 43 that stores the indoor temperature distribution acquired by the temperature acquisition means 42. The memory unit 43 stores the acquired temperatures and positions of people, objects, air (air currents), etc., in the room.

[0021] The control unit 10 also includes a blower fan control means 41 that changes the rotation speed of the indoor blower fan 7 to vary the airflow volume depending on the temperature difference between the current room temperature T detected by the room temperature sensor 8 and the set room temperature (target room temperature) T0 set by the remote control 30.

[0022] In the control block diagram of the air conditioner 1 in FIG. 3, the output side of the control unit 10 is connected to an outdoor control unit of the outdoor unit 11, although not shown.

[0023] Next, the temperature acquisition means using an infrared sensor in the embodiment of the present invention will be described in detail.

[0024] FIG. 5 shows two types of temperature distributions acquired by rotating the infrared sensor 15, with the heat source being a person 100. FIG. 5(A) shows thermal images (a1)-(a2) acquired by one pixel of the pixel unit 16 by rotating and scanning the infrared sensor 15 at a first step angle of 5° using the infrared sensor driving unit 17. FIG. 5(B) shows thermal images (b1)-(b6) acquired by one pixel of the pixel unit 16 by rotating and scanning the infrared sensor 15 at a second step angle of 1°, which is smaller than the first step angle. The temperatures shown in each thermal image indicate the absolute value of the average temperature in the area of ​​each thermal image.

[0025] In FIG. 5(A), the temperature distribution is acquired at a first step angle, which is the same angle as the field of view per pixel of the infrared sensor 15. This makes it difficult to acquire a thermal image that captures the heat source, the person 100, at the horizontal center (shown by the dashed line). For example, in thermal image (a2), the center of the person 100 is far from the center of the thermal image. On the other hand, in FIG. 5(B), the temperature distribution is acquired at a second step angle, which is smaller than the first step angle. This makes it easier to acquire a thermal image that captures the heat source, the person 100, at the horizontal center. For example, in thermal image (b3), the center of the person 100 and the center of the thermal image are roughly aligned. Comparing the temperatures of the thermal images, thermal image (a2) does not capture the entire person 100 within the region, resulting in a low detected temperature of 28°C for a person. However, thermal image (b3) captures the entire person 100 within the region, resulting in a detected temperature of 32°C, which is appropriate for a person. In other words, the control unit 10 can obtain a more accurate detected temperature by subdividing the step angle for rotationally scanning the infrared sensor 15. Also, while there are two thermal images in FIG. 5(A), six thermal images are obtained in FIG. 5(B), which allows for more detailed acquisition of the shape and size of the heat source, the person 100. Here, in FIG. 5, the heat source to be measured is the person 100, but it may also be an object other than a person, such as air (airflow), or an electrical device such as the heater 2.

[0026] In this embodiment, the first temperature acquisition means is a temperature acquisition means that acquires positional information of people and non-people heat sources in a room by rotating and scanning the infrared sensor 15 at a first step angle of 5°, as shown in Fig. 5(A).The second temperature acquisition means is a temperature acquisition means that acquires positional information of people and non-people heat sources in a room by rotating and scanning the infrared sensor 15 at a second step angle of 1°, which is smaller than the first step angle, as shown in Fig. 5(B).The control unit 10 appropriately selects between the first temperature acquisition means and the second temperature acquisition means using the temperature acquisition means 42 to acquire the temperature distribution in the room.

[0027] When the indoor unit 3 of the air conditioner 1 is in operation, air conditioning control is performed based on the indoor temperature distribution acquired by the temperature acquisition means 42. For example, air conditioning control includes turning operation on / off depending on whether people are present / absent, directing heated air or cooled air toward / avoiding people (approaching / avoiding people), and eliminating the temperature difference between the upper part (head) and lower part (feet) of the room. If it is not possible to distinguish between people and heat sources other than people when performing these air conditioning controls, erroneous determinations and malfunctions may occur, such as continuing operation even when people are absent, not properly directing / avoiding people, or not eliminating the temperature difference between heads and feet.

[0028] Therefore, when the indoor unit 3 starts operating, the second temperature acquisition means is implemented to accurately acquire the temperature and position of people, objects, air (airflow), etc. in the room, i.e., the temperature distribution, and more accurately acquire location information of the heat source. In other words, by accurately grasping the location information of the heat source in a situation where there is absolutely no information about the heat source in the room, such as when operation starts, erroneous judgments and malfunctions of the air conditioning control can be prevented. Furthermore, the control unit 10 can accurately distinguish and determine whether a heat source is human or non-human by determining the temperature, shape, and size of the heat source, as well as whether the heat source is moving, using the temperature distribution information accurately acquired by the second temperature acquisition means. This further prevents erroneous judgments and malfunctions of the air conditioning control.

[0029] The second temperature acquisition means can acquire the entire temperature distribution in the room by one-way scanning, i.e., by scanning the scanning range in Figure 2 from one end to the other, but it may also be performed repeatedly until the indoor temperature reaches the target temperature, or it may be performed for a predetermined period of time.

[0030] Furthermore, the second temperature acquisition means has the disadvantage of being difficult to follow the rapid movements of people because it rotates and scans at small step angles. Therefore, the control unit 10 can perform air conditioning control that follows the movement and movement of people by executing the second temperature acquisition means for a predetermined time and then the first temperature acquisition means. In other words, after the second temperature acquisition means distinguishes between people and non-people heat sources, the first temperature acquisition means performs air conditioning control that follows the rapid movements of people, such as approaching or avoiding people, thereby improving user comfort.

[0031] Furthermore, the second temperature acquisition means rotates and scans the infrared sensor 15 at a finer second step angle, so it takes several minutes to acquire the temperature distribution in the room. However, the first temperature acquisition means rotates and scans at a first step angle that is larger than the second step angle, so the temperature distribution in the room can be acquired in a relatively short time. This makes it possible to control air conditioning in response to rapid temperature changes caused by people moving around.

[0032] While the indoor unit 3 is operating, the temperature distributions acquired by the first temperature acquisition means and the second temperature acquisition means are stored in the memory unit 43 of the control unit 10 as needed. When the first temperature acquisition means is executed, air conditioning control is performed to track rapid temperature changes based on the position information of people and non-people, based on the temperature distribution previously stored by the second temperature acquisition means. Meanwhile, temperature changes based on the position information of heat sources other than people are not reflected in the air conditioning control. In other words, even if a temperature change occurs due to a change in the output of an electrical appliance such as the heater 2, the temperature change of an object identified as a heat source other than people is not subject to air conditioning control, such as targeting or avoiding people, and operation continues. This ensures that air conditioning control is performed only for people, eliminating unnecessary operation and improving comfort.

[0033] In Figure 2, if person 100a moves to position 100b while the first temperature acquisition means is being executed, the control unit 10 acquires the temperature distribution that changes from Figure 6(a) to (b) using the first temperature acquisition means. Here, the heater 2 is identified as a heat source other than a person based on the temperature distribution stored by the second temperature acquisition means, so the control unit 10 does not target the heater 2 as a heat source other than a person, and operates the indoor unit 3. On the other hand, based on the temperature, shape, and size of the heat source, as well as the movement of the heat source from Figure 6(a) to the position shown in Figure 6(b), the control unit 10 determines that people 100a and 100b are people, and operates the indoor unit 3 as a target for air-conditioning control aimed at people, such as hitting or avoiding the person.

[0034] Although the infrared sensor 15 is rotated and scanned only in the horizontal direction, it may also be rotated and scanned in the vertical direction, thereby making it possible to obtain the temperature distribution in the room over a wider range.

[0035] The viewing angle that can be acquired by one pixel of infrared sensor 15 is set to 5° in the horizontal direction and 7° in the vertical direction, but may be set appropriately according to the specifications of infrared sensor 15. Also, although the first step angle is set to the same as the viewing angle of 5° of infrared sensor 15, this is not limited to this, and a step angle that can follow the movement of a person may be set appropriately.

[0036] Furthermore, the other configurations used in the present embodiment are presented as examples and are not intended to limit the scope of the invention, and the invention can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and spirit of the invention, and are also included in the inventions described in the claims and their equivalents. [Explanation of symbols]

[0037] 1. Air conditioner 3 Indoor unit 4 Intake port 5 Air outlet 7 Indoor ventilation fan 10 Control Unit 15 Infrared sensor 30 Remote Control 42 Temperature acquisition means

Claims

1. an indoor unit that draws in indoor air through an intake port and then blows it out through an outlet using a variable airflow fan; a remote control for operating the indoor unit; a control unit that controls the air conditioning of the indoor unit in accordance with instructions from the remote controller; an infrared sensor that detects the temperature distribution in the room where the indoor unit is installed by rotating and scanning; the control unit rotates and scans the infrared sensor at a predetermined first step angle to acquire position information of a heat source in a room; and a second temperature acquisition means for acquiring position information of a person in a room by rotating and scanning the infrared sensor at a second step angle smaller than the first step angle; The air conditioner is characterized in that the second temperature acquisition means is executed when the indoor unit starts operating.

2. The air conditioner according to claim 1, characterized in that, when the second temperature acquisition means is executed, the control unit determines whether the object is a person or not based on the results acquired by the second temperature acquisition means.

3. The air conditioner according to claim 2, wherein the control unit executes the first temperature acquisition unit after executing the second temperature acquisition unit for a predetermined time.

4. The control unit, when the first temperature acquisition means is executed, Based on the result of determining whether the temperature acquired by the second temperature acquisition means is a human or a non-human, The air conditioner according to claim 3, wherein air conditioning control is performed based on the position information of the person in the room, while temperature changes in the position information of heat sources other than the person are not reflected in the air conditioning control.

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