An inductive sensing device, method and apparatus having a metal housing

Abstract

The application provides an inductive detection device and method and a device with a metal shell, which comprises an insulating layer, a metal inductive component and a controller, wherein the insulating layer is arranged between the metal shell and the metal inductive component; the controller is connected with the metal inductive component, the controller emits a detection signal with a set frequency to the metal inductive component and collects an inductive voltage of the metal inductive component; and the controller determines a target object inductive detection result of the metal shell according to the relationship between the inductive voltage and a preset voltage. When a target object such as a person approaches the metal inductive component, the capacitance value between the metal inductive component and the ground is increased, so that the inductive voltage value is reduced, and thus the relationship between the collected inductive voltage and the preset voltage can be used to accurately detect whether the target object appears at the metal shell, so as to realize the human body proximity induction function of the metal shell product and improve the user experience of the metal shell product.

Description

Technical Field

[0001] This invention relates to the field of household appliance technology, and specifically to a sensing detection device, method, and equipment with a metal casing. Background Technology

[0002] Because metal has electromagnetic shielding properties, most household appliances with proximity sensors are either non-metallic or have no other metal parts near the sensor. However, for products with metal casings, such as electric heaters, the air outlet gets very hot. To prevent accidental burns from touching the metal grille at the outlet, a proximity sensor is needed at the air outlet. However, due to the metallic material of the grille, there is currently no good solution. Summary of the Invention

[0003] In view of this, embodiments of the present invention provide a sensing detection device, method, and device with a metal casing to overcome the problem that products with metal casings in the prior art are difficult to realize human proximity sensing function.

[0004] According to a first aspect, embodiments of the present invention provide a sensing detection device applied to a device having a metal casing, the device comprising: an insulating layer, a metal sensing component, and a controller, wherein...

[0005] The insulating layer is disposed between the metal outer casing and the metal sensing component;

[0006] The controller is connected to the metal sensing component. The controller sends a detection signal of a set frequency to the metal sensing component and collects the sensing voltage of the metal sensing component.

[0007] The controller determines the target object sensing detection result of the metal casing based on the relationship between the sensed voltage and the preset voltage.

[0008] Optionally, the sensing and detection device further includes a power supply, which is connected to the controller.

[0009] Optionally, the sensing and detection device further includes a driving circuit, the input terminal of which is connected to the output terminal of the controller, and the output terminal of which is connected to the load of the device, wherein the controller drives the device to work through the driving circuit.

[0010] Optionally, the power supply is an isolated power supply, and the driving circuit is an isolated driving circuit.

[0011] Optionally, the power supply is a non-isolated power supply, the drive circuit is a non-isolated drive circuit, and a protective impedance is provided between the controller and the metal sensing component.

[0012] Optionally, the distance between the metal casing and the metal sensing component is determined by the target object detection distance of the metal casing.

[0013] Optionally, the controller includes: a comparator,

[0014] The induced voltage of the metal sensing component is input to the first input terminal of the comparator, the second input terminal of the comparator is connected to the preset voltage, and the output terminal of the comparator outputs the target object sensing detection result of the metal casing.

[0015] Optionally, the insulating layer is fixed to the metal housing, and the metal sensing component is fixed to the insulating layer; the metal housing is connected to ground.

[0016] Optionally, the distance between the metal casing and the metal sensing element is in the range of 1mm-100mm.

[0017] According to a second aspect, embodiments of the present invention provide a sensing detection method, applied to the sensing detection device described in the first aspect and any optional embodiment thereof, the method comprising:

[0018] A detection signal of a set frequency is emitted to the metal sensing component, and the induced voltage of the metal sensing component is collected;

[0019] The target object detection result of the metal casing is determined based on the relationship between the induced voltage and the preset voltage.

[0020] Optionally, determining the target object detection result of the metal casing based on the relationship between the induced voltage and the preset voltage includes:

[0021] Determine whether the induced voltage is less than the preset voltage;

[0022] When the induced voltage is less than the preset voltage, the target object detection result of the metal casing is determined to be that a target object exists around the metal casing;

[0023] When the induced voltage is not less than the preset voltage, the target object detection result of the metal casing is determined to be that there is no target object around the metal casing.

[0024] Optionally, when the device has a heating function, after determining that the target object detection result of the metal casing indicates the presence of a target object around the metal casing, the method further includes:

[0025] If the device is in non-heating mode, then increase the operating power of the device;

[0026] If the device is in heating mode, reduce the device's operating power or control the device to stop operating.

[0027] According to a third aspect, embodiments of the present invention provide a device having a metal casing, the device comprising: the sensing detection device described in the first aspect and any alternative embodiment thereof.

[0028] Optionally, the device is an electric heater, and the metal sensing component is located at the air outlet of the electric heater.

[0029] The technical solution of this invention has the following advantages:

[0030] 1. The sensing detection device provided in this embodiment of the invention includes: an insulating layer, a metal sensing component, and a controller, applied to a device with a metal casing. The insulating layer is disposed between the metal casing and the metal sensing component; the controller is connected to the metal sensing component, and the controller transmits a detection signal of a set frequency to the metal sensing component and collects the induced voltage of the metal sensing component; the controller determines the target object sensing detection result of the metal casing based on the relationship between the induced voltage and the preset voltage. Thus, the insulating layer achieves insulation between the metal sensing component and the metal casing, avoiding interference from the metal casing to the sensing detection result. By using the controller to transmit a detection signal of a fixed frequency to the metal sensing component, when a target object, such as a person, approaches the metal sensing component, the induced voltage value decreases. Therefore, by using the relationship between the collected induced voltage and the preset voltage, the presence of a target object at the metal casing can be accurately detected, thereby realizing the human proximity sensing function of the metal casing product and improving the user experience of the metal casing product.

[0031] 2. The sensing detection method provided in this embodiment of the invention is applied to a sensing detection device provided in another embodiment of the invention. It transmits a detection signal of a set frequency to a metal sensing component and collects the sensing voltage of the metal sensing component. The detection result of the target object on the metal casing is determined based on the relationship between the sensing voltage and a preset voltage. Thus, by using a controller to transmit a detection signal of a fixed frequency to the metal sensing component, when a target object, such as a person, approaches the metal sensing component, the sensing voltage value decreases. Therefore, by using the relationship between the collected sensing voltage and the preset voltage, the presence of the target object on the metal casing can be accurately detected, thereby realizing the human proximity sensing function of the metal casing product and improving the user experience of the metal casing product.

[0032] 3. The device with a metal casing provided in this embodiment of the invention includes a sensing detection device provided in another embodiment of the invention. This utilizes an insulating layer to insulate the metal sensing component from the metal casing, preventing interference from the metal casing with the sensing detection results. By using a controller to emit a detection signal of a fixed frequency to the metal sensing component, when a target object, such as a person, approaches the metal sensing component, the sensing voltage decreases. Therefore, by using the relationship between the collected sensing voltage and a preset voltage, the presence of the target object at the metal casing can be accurately detected, thereby realizing the human proximity sensing function of the metal casing product and improving the user experience of the metal casing product. Attached Figure Description

[0033] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0034] Figure 1 This is a schematic diagram of the structure of a device with a metal casing according to an embodiment of the present invention;

[0035] Figure 2 This is a schematic diagram of the specific structure of the sensing and detection device according to an embodiment of the present invention;

[0036] Figure 3 This is another specific structural schematic diagram of the sensing detection device according to an embodiment of the present invention;

[0037] Figure 4 This is a flowchart of the sensing detection method according to an embodiment of the present invention;

[0038] Figure 5 This is a schematic diagram illustrating the specific working process of a device with a metal casing according to an embodiment of the present invention. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0040] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0041] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can also refer to the internal connection of two components; and they can refer to a wireless connection or a wired connection. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0042] The technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0043] Because metal has electromagnetic shielding properties, most household appliances with proximity sensors are either non-metallic or have no other metal parts near the sensor. However, for products with metal casings, such as electric heaters, the air outlet gets very hot. To prevent accidental burns from touching the metal grille at the outlet, a proximity sensor is needed at the air outlet. However, due to the metallic material of the grille, there is currently no good solution.

[0044] To address the aforementioned problems, embodiments of the present invention provide a sensing detection device, applicable to, for example... Figure 1 The device shown has a metal casing, such as Figure 1 As shown in Figure 2, the sensing detection device includes: an insulating layer 102, a metal sensing component 101, and a controller (not shown in the figure). The insulating layer 102 is disposed between the metal casing 103 and the metal sensing component 101. The controller is connected to the metal sensing component 101, and the controller transmits a detection signal of a set frequency to the metal sensing component 101 and collects the sensing voltage of the metal sensing component 101. The controller determines the target object sensing detection result of the metal casing 103 according to the relationship between the sensing voltage and the preset voltage.

[0045] The aforementioned metal sensing component 101 can be a metal sensing line, a metal sensing coil, a metal sensing mesh, or a metal sensing panel, etc. Its specific shape and area can be flexibly customized according to actual sensing and detection needs, and this invention is not limited thereto. The aforementioned insulating layer 102 can be a layer made of insulating materials such as high-temperature resistant plastic grids.

[0046] Specifically, in this embodiment of the invention, an electric heater with a metal casing is used as an example. This electric heater has functions such as air delivery, heating, humidification, or air filtration. A metal sensing component 101 is located at the air outlet of the electric heater, thereby enabling a human body sensing function at the air outlet. This facilitates timely detection of a person at the air outlet, allowing for timely adjustment of the heater's operating mode to improve the user experience and prevent burns during heating. In practical applications, this device can also be other products with a metal casing 103, such as an electric fan, etc., and the invention is not limited to this.

[0047] Specifically, in one embodiment, the controller includes a comparator. The induced voltage of the metal sensing component 101 is input to the first input terminal of the comparator, a preset voltage is externally connected to the second input terminal of the comparator, and the output terminal of the comparator outputs the target object sensing detection result of the metal casing 103. In practical applications, this comparator can be integrated into the control unit of the device, such as an MCU, thereby realizing the human proximity sensing function through hardware logic processing, reducing the configuration requirements of the controller, and further reducing the cost of the product.

[0048] The sensing detection device provided in this invention generates an electromagnetic field at the metal sensing component by transmitting a fixed-frequency detection signal to the metal sensing component using a controller. The capacitance between the metal sensing component and ground is used to collect a corresponding induced voltage value at the metal sensing component. When a target object, such as a person, approaches the metal sensing component, the capacitance between the metal sensing component and ground increases, thereby reducing the induced voltage value. By using the relationship between the collected induced voltage and the induced voltage value when no one is approaching (i.e., a preset voltage), the device can accurately detect whether a target object is present at the metal casing, thus realizing the human proximity sensing function of the metal casing product and improving the user experience of the metal casing product.

[0049] For example, an experiment can be conducted where the MCU sends a fixed-frequency detection signal to the metal sensing component 101. This creates an electromagnetic field at the metal sensing component 101. The capacitance between the metal sensing component 101 and ground is used to collect the induced voltage at the metal sensing component 101 when no one is around. The average or minimum value of the induced voltage obtained through multiple experiments is then determined as the preset voltage. When a human or animal approaches the metal casing 103 of the product and the metal sensing component 101, the capacitance between the metal sensing component 101 and ground increases, causing the induced voltage to decrease. By comparing the preset voltage with the real-time detected induced voltage using a comparator, it can be determined whether a human or animal is near the heater. This allows for flexible adjustment of the heater's operation, such as stopping heating to prevent burns, thus improving the user experience.

[0050] Specifically, in one embodiment, the controller described above is the control unit of the device, such as the MCU of an electric heater. Therefore, there is no need to set up an additional controller; the sensing and detection function can be achieved using only the device's own controller, saving production costs.

[0051] Specifically, in one embodiment, such as Figure 1 As shown, the insulating layer 102 is fixed to the metal casing 103, and the metal sensing element 101 is fixed to the insulating layer 102. For example, a high-temperature resistant plastic grille is provided on the metal grille of the electric heater's air outlet, and then the metal sensing coil is nested on the plastic grille. By fixing the metal sensing element 101 and the metal casing 103 together using the insulating layer, the product's sensing and detection function can be achieved without significantly increasing the product's size. The insulating layer 102 prevents the metal casing 103 from interfering with the signal of the metal sensing element 101. Furthermore, the metal casing 103 is connected to ground to ensure safety during product use. In practical applications, such as... Figure 2 As shown in Figure 3, the metal casing 103 can be connected to the power ground GND of the MCU to serve as a reference ground for signal sampling, and also serves to shield against interference.

[0052] Specifically, in one embodiment, the sensing detection device provided by this invention further includes a power supply connected to a controller. In practical applications, this power supply can also be the power supply for the aforementioned device, thereby further reducing device costs by sharing a power supply. Furthermore, the sensing detection device for a device with a metal casing provided by this invention also includes a drive circuit. The input terminal of the drive circuit is connected to the output terminal of the controller, and the output terminal is connected to the load of the device. The controller drives the device to operate through the drive circuit. For example, the output terminal of the drive circuit is connected to a load such as the heating element or motor of an electric heater.

[0053] For example, such as Figure 2 As shown, the power supply is an isolated power supply, and the drive circuit is an isolated drive circuit. Specifically, the isolated power supply can be a safety isolation transformer, or a flyback switching power supply that meets safety isolation requirements, etc. The isolated drive circuit is a drive circuit with safety isolation function. The specific circuit structure can be implemented with reference to the design of relevant drive circuits in the prior art, and will not be described in detail here.

[0054] For example, such as Figure 3 As shown, the power supply is a non-isolated power supply, and the drive circuit is a non-isolated drive circuit. A protective impedance, such as a Y capacitor, is provided between the controller and the metal sensing component 101. Additionally, a protective impedance is also provided between the MCU and the metal casing 103. By adjusting the value of the protective impedance, both the sensing effect and interference signal shielding can be optimized, while meeting safety requirements. In practical applications, the aforementioned non-isolated power supply can be a buck switching power supply, buck-boost switching power supply, etc. The non-isolated drive circuit is a drive circuit without safety isolation. The specific circuit structure can be implemented by referring to the design of relevant drive circuits in the prior art, and will not be elaborated further here.

[0055] In practical applications, the aforementioned power supply connects to the mains power supply to the low-voltage loads of the electric heater, such as the MCU, display, and buzzer, and the MCU controls the drive circuit to drive the high-voltage loads such as the heating element and motor.

[0056] Specifically, in one embodiment, the distance between the metal casing 103 and the metal sensing component 101 is determined by the target object detection distance of the metal casing 103. In practical applications, it is necessary to combine hardware circuit PCB layout, software filtering algorithms, etc., and to debug it to meet both the detection distance requirements and EMC anti-interference tests such as injection current and EFT. Generally, the greater the distance between the metal sensing component 101 and the metal casing 103, the greater the target object detection distance, but the corresponding anti-interference capability is worse. In practical applications, the distance between the metal casing 103 and the metal sensing component 101 is in the range of 1mm-100mm. Within this distance range, the human proximity sensing effect and interference signal shielding are both well achieved, which can meet the anti-scalding detection distance requirements of most products such as electric heaters and improve the user experience.

[0057] Furthermore, in practical applications, the shape and size of the metal sensing component 101 will also affect the detection distance. For example, the larger the area, the farther the sensing distance. Therefore, after adjusting the distance between the metal sensing component 101 and the metal housing 103, the detection distance can also be adjusted by changing the shape and size of the metal sensing component 101 to meet the needs of different products and different application scenarios and improve the flexibility of product design.

[0058] The aforementioned sensing and detection device can ensure that the metal casing product can effectively and reliably realize the human proximity sensing function; by adjusting the safety distance between the metal sensing component 101 and the metal casing 103, the detection distance of the human proximity sensing can be flexibly adjusted; in addition, by configuring different power supplies and drive circuits, the power supply and load drive problems caused by safety regulations for metal casing products are solved, realizing safe power supply and safe detection, and ensuring the safety of the product.

[0059] This invention provides a sensing detection method, which is applied to a sensing detection device provided in another embodiment of this invention, such as... Figure 4 As shown, the sensing detection method includes the following steps:

[0060] Step S101: Transmit a detection signal of a set frequency to the metal sensing component and collect the induced voltage of the metal sensing component.

[0061] Step S102: Determine the target object detection result of the metal casing based on the relationship between the induced voltage and the preset voltage.

[0062] Specifically, step S102 involves determining whether the induced voltage is less than a preset voltage; when the induced voltage is less than the preset voltage, determining that the target object detection result of the metal casing indicates the presence of a target object around the metal casing; and when the induced voltage is not less than the preset voltage, determining that the target object detection result of the metal casing indicates the absence of a target object around the metal casing.

[0063] Specifically, when the device has a heating function, such as when the device is an electric heater, after determining that the target object detection result of the metal casing indicates the presence of a target object around the metal casing, the sensing detection of the device with a metal casing provided in this embodiment of the invention further includes the following steps:

[0064] Step S201: If the device is in non-heating mode, increase the device's operating power.

[0065] Step S202: If the equipment is in heating mode, reduce the operating power of the equipment or control the equipment to stop operating.

[0066] For example, such as Figure 5 As shown, when a person is not near the air outlet of the electric heater, the metal sensor detects a reference voltage U0. When a person approaches the air outlet, the metal sensor detects a voltage U0 - ΔU. When the electric heater is in fan mode, the threshold value is U1. If the detection result satisfies U0 - ΔU ≤ U1, meaning a person is detected near the air outlet, the fan speed is increased, increasing the airflow and distance. This can be set according to actual needs. When the electric heater is in heating mode, the threshold value is U2. If the detection result satisfies U0 - ΔU ≤ U2, meaning a person is detected near the air outlet, the heating element is cut off or the power is reduced to prevent burns. Both U1 and U2 are values ​​less than or equal to U0; they can be the same or different, and can be configured according to actual needs. In practical applications, the air supply mode has a higher threshold and a longer sensing distance to enhance the heating effect when people are present, thus improving the user experience. The heating mode has a lower threshold and a shorter sensing distance. The closer the person is, the lower the detected voltage will be, thereby avoiding close-range burns.

[0067] By performing the above steps, the sensing detection method provided in this embodiment of the invention generates an electromagnetic field at the metal sensing component by using a controller to emit a detection signal of a fixed frequency to the metal sensing component. The corresponding induced voltage value is collected at the metal sensing component by utilizing the capacitance value formed between the metal sensing component and the ground. When a target object, such as a person, approaches the metal sensing component, the capacitance value between the metal sensing component and the ground increases, thereby reducing the induced voltage value. By using the relationship between the collected induced voltage and the induced voltage corresponding to when no one is approaching, i.e., the preset voltage, it is possible to accurately detect whether the target object is present at the metal casing, thereby realizing the human proximity sensing function of the metal casing product and improving the user experience of the metal casing product.

[0068] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A sensing detection device, applied to equipment with a metal casing, characterized in that, The device includes: an insulating layer, a metal sensing component, and a controller, wherein... The insulating layer is disposed between the metal outer shell and the metal sensing component; the insulating layer is a high-temperature resistant plastic grid. The controller is connected to the metal sensing component. The controller sends a detection signal of a set frequency to the metal sensing component and collects the sensing voltage of the metal sensing component. The controller determines the target object sensing detection result of the metal casing based on the relationship between the sensed voltage and the preset voltage. The device is an electric heater, and the metal sensing component is located at the air outlet of the electric heater. After the controller determines that the target object detection result of the metal casing is that there is a target object around the metal casing, if the device is in heating mode, it reduces the operating power of the device or controls the device to stop operating. The distance between the metal casing and the metal sensing component is determined by the target object detection distance of the metal casing; The controller includes: a comparator, The induced voltage of the metal sensing component is input to the first input terminal of the comparator, the second input terminal of the comparator is connected to the preset voltage, and the output terminal of the comparator outputs the target object sensing detection result of the metal casing; when a human body approaches the metal sensing component, the capacitance between the metal sensing component and the ground will increase, thereby reducing the induced voltage value. The insulating layer is fixed to the metal outer shell, and the metal sensing component is fixed to the insulating layer; The metal casing is connected to the ground; The distance between the metal casing and the metal sensing component ranges from 1mm to 100mm. When the device is in air supply mode, if it detects a person approaching the air outlet, it will increase the airflow level to increase the air volume and air supply distance.

2. The sensing detection device according to claim 1, characterized in that, Also includes: A power supply, which is connected to the controller.

3. The sensing detection device according to claim 2, characterized in that, Also includes: A drive circuit is provided, the input of which is connected to the output of the controller, and the output of which is connected to the load of the device. The controller drives the device to work through the drive circuit.

4. The sensing detection device according to claim 3, characterized in that, The power supply is an isolated power supply, and the driving circuit is an isolated driving circuit.

5. The sensing detection device according to claim 3, characterized in that, The power supply is a non-isolated power supply, the drive circuit is a non-isolated drive circuit, and a protective impedance is provided between the controller and the metal sensing component.

6. A sensing detection method, applied to the sensing detection device as described in any one of claims 1-5, characterized in that, The method includes: A detection signal of a set frequency is emitted to the metal sensing component, and the induced voltage of the metal sensing component is collected; The target object detection result of the metal casing is determined based on the relationship between the induced voltage and the preset voltage.

7. The method according to claim 6, characterized in that, The step of determining the target object detection result of the metal casing based on the relationship between the induced voltage and the preset voltage includes: Determine whether the induced voltage is less than the preset voltage; When the induced voltage is less than the preset voltage, the target object detection result of the metal casing is determined to be that a target object exists around the metal casing; When the induced voltage is not less than the preset voltage, the target object detection result of the metal casing is determined to be that there is no target object around the metal casing.

8. The method according to claim 7, characterized in that, When the device has a heating function, after determining that the target object detection result of the metal casing indicates the presence of a target object around the metal casing, the method further includes: If the device is in non-heating mode, then increase the operating power of the device; If the device is in heating mode, reduce the device's operating power or control the device to stop operating.

9. A device having a metal casing, characterized in that, The device includes: a sensing detection device as described in any one of claims 1-5, wherein the device is an electric heater.

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