Display device

Abstract

Embodiments of the present application provide a display device, comprising: a camera configured to collect image data; a stepper motor configured to control the camera to rise or fall; a detection component configured to collect data of the camera in the process of rising or falling; a display screen configured to display a user interface and / or image data collected by the camera; and a controller configured to input an SPWM signal to the stepper motor to drive the stepper motor in a subdivided manner, and adjust the SPWM signal according to the data collected by the detection component to adjust the moving speed of the camera in the process of rising or falling. Embodiments of the present application can make the operation process of the stepper motor smoother, thereby reducing the noise generated by the stepper motor due to shaking; at the same time, the moving speed of the camera can also be adjusted to further reduce the noise generated by the camera in the moving process.

Description

TECHNICAL FIELD

[0001] Embodiments of the present application relate to the technical field of automatic control, and particularly relate to a display device. BACKGROUND

[0002] With the rapid development of television intelligence, the television has developed into an intelligent display device integrating images, sound and various sensors. For example, through the television camera, action recognition, video call and other functions can be realized.

[0003] At present, considering that the television camera will cause privacy problems for the user if it continuously works, therefore, it is best to hide the camera when the camera is not used. Among them, the lifting type camera is favored by the majority of users because of its flexible opening mode.

[0004] However, the current lifting type camera produces relatively large noise when lifting, which will bring poor user experience to the user in a relatively quiet environment. SUMMARY

[0005] Embodiments of the present application provide a display device, which can solve the technical problem of the current lifting type camera producing relatively large noise when lifting.

[0006] In some embodiments, the display device described above comprises:

[0007] a camera configured to collect image data;

[0008] a stepping motor configured to control the camera to rise or fall;

[0009] a detection component configured to collect data of the camera in the process of rising or falling;

[0010] a display screen configured to display a user interface and / or image data collected by the camera;

[0011] a controller connected with the stepping motor, the controller being configured to:

[0012] input a sinusoidal pulse width modulation (SPWM) signal to the stepping motor to drive the stepping motor in a subdivided manner;

[0013] obtain the data of the camera in the process of rising or falling collected by the detection component;

[0014] adjust the SPWM signal according to the data of the camera in the process of rising or falling, so as to adjust the moving speed of the camera in the process of rising or falling.

[0015] In a possible implementation, the controller is configured to:

[0016] determining a movement mode currently set for the camera, the movement mode of the camera including a standard mode, a soft mode, and a quiet mode;

[0017] when the movement mode currently set for the camera is the standard mode, keeping the SPWM signal input to the stepper motor unchanged;

[0018] when the movement mode currently set for the camera is the soft mode or the quiet mode, adjusting the SPWM signal according to data of the camera in the process of rising or falling.

[0019] In an embodiment, the detection assembly includes a plurality of Hall devices, each of the Hall devices being arranged at equal intervals in a movement path of the camera.

[0020] The controller is configured to:

[0021] when the movement mode currently set for the camera is the soft mode, obtaining detection data of each of the Hall devices, and determining a current position of the camera according to the detection data of each of the Hall devices;

[0022] adjusting the SPWM signal according to the current position of the camera.

[0023] In an embodiment, the controller is configured to:

[0024] when it is determined that the camera is in a preset starting section or ending section, adjusting a frequency of the SPWM signal from a default frequency value to a first frequency value; the starting section and the ending section are located at two ends of the movement path of the camera, and the starting section and the ending section have no intersection; the first frequency value is less than the default frequency value;

[0025] when it is determined that the camera is between the starting section and the ending section, adjusting the frequency of the SPWM signal to recover to the default frequency value.

[0026] In an embodiment, the detection assembly includes a microphone, and the microphone is used to collect noise data of the camera in the process of movement.

[0027] The controller is configured to:

[0028] when it is determined that the camera is in a preset starting section or ending section, obtaining noise data collected by the microphone;

[0029] if the decibel value of the noise data is greater than or equal to a preset decibel threshold, adjusting a frequency of the SPWM signal from a default frequency value to a first frequency value;

[0030] if the decibel value of the noise data is less than the preset decibel threshold, restoring the frequency of the SPWM signal to the default frequency value.

[0031] In an implementation, the detection component includes a microphone configured to collect noise data of the camera during movement thereof;

[0032] The controller is configured to:

[0033] when it is determined that the camera is currently set to the quiet mode, collecting noise data of the camera during movement thereof in real time by the microphone;

[0034] if the decibel value of the noise data is greater than or equal to a preset decibel threshold, adjusting a frequency of the SPWM signal from a default frequency value to a first frequency value; the first frequency value is less than the default frequency value;

[0035] if the decibel value of the noise data is less than the preset decibel threshold, restoring the frequency of the SPWM signal to the default frequency value.

[0036] In an implementation, the detection component includes an H-bridge circuit configured to provide a driving current to the stepper motor;

[0037] The controller is configured to:

[0038] during movement of the camera, determining a driving current value provided by the H-bridge circuit to the stepper motor;

[0039] when the driving current value is greater than a preset current threshold, adjusting an amplitude of the SPWM signal from a default amplitude to a first amplitude; the first amplitude is greater than the default amplitude.

[0040] In an implementation, the detection component includes a plurality of Hall devices, each of which is arranged at an equal interval in a movement path of the camera;

[0041] The controller is configured to:

[0042] during movement of the camera, determining a movement speed of the camera according to detection data of each of the Hall devices;

[0043] When the moving speed of the camera is less than a preset moving speed corresponding to a current input SPWM signal of the stepping motor, the amplitude of the current input SPWM signal of the stepping motor is adjusted from a default amplitude to a first amplitude; the first amplitude is greater than the default amplitude.

[0044] In an implementable embodiment, the detection component comprises a microphone, which is configured to collect noise data of the camera during movement;

[0045] The controller is configured to:

[0046] After the amplitude of the SPWM signal is adjusted from the default amplitude to the first amplitude, if the decibel value of the noise data collected by the microphone is greater than or equal to a preset decibel threshold, the frequency of the SPWM signal is adjusted from a default frequency value to a first frequency value, and the first frequency value is less than the default frequency value.

[0047] In an implementable embodiment, the detection component comprises a grating ruler, which is configured to detect the rotation angle of the stepping motor;

[0048] The controller is configured to:

[0049] The rotation angle of the stepping motor detected by the grating ruler is acquired;

[0050] It is determined whether the rotation angle of the stepping motor is the same as a target angle of the stepping motor controlled by the controller:

[0051] If the rotation angle of the stepping motor is not the same as the target angle, the stepping motor is controlled to rotate to the target angle.

[0052] The display device provided by the embodiments can drive the stepping motor in a subdivided manner by inputting the SPWM signal to the stepping motor, so that the operation process of the stepping motor is smoother, and thus the noise generated by the stepping motor due to vibration is reduced. Meanwhile, the data of the camera collected by the detection component during the lifting or lowering process is used to adjust the SPWM signal, so as to adjust the moving speed of the camera during the lifting or lowering process, and thus the noise generated by the camera during the lifting or lowering process can be further reduced. BRIEF DESCRIPTION OF DRAWINGS

[0053] Figure 1 FIG. 1 schematically shows an operating scenario between a display device and a control device according to an embodiment;

[0054] Figure 2 FIG. 2 schematically shows a hardware configuration block diagram of the display device 200 according to an exemplary embodiment;

[0055] Figure 3 Fig. 1 is a schematic diagram of a principle of generating vibration noise of a stepping motor in an embodiment of the present application;

[0056] Figure 4 Fig. 2 is a schematic diagram of a structure of a display device 200 in an exemplary embodiment of the present application Figure 1 ;

[0057] Figure 5 Fig. 3 is a schematic diagram of another structure of the display device 200 in an exemplary embodiment of the present application Figure 2 ;

[0058] Figure 6 Fig. 4 is a schematic diagram of a synthesis diagram of 1 / 8 subdivided current vectors in an exemplary embodiment of the present application

[0059] Figure 7 Fig. 5 is a schematic diagram of still another structure of the display device 200 in an exemplary embodiment of the present application Figure 3 ;

[0060] Figure 8 Fig. 6 is a schematic diagram of still another structure of the display device 200 in an exemplary embodiment of the present application Figure 4 ;

[0061] Figure 9 Fig. 7 is a schematic diagram of still another structure of the display device 200 in an exemplary embodiment of the present application Figure 5 ;

[0062] Figure 10 Fig. 8 is a flowchart of a lifting camera control method provided in an embodiment of the present application. DETAILED DESCRIPTION

[0063] In order to make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the scope of protection of the present application. In addition, although the disclosure is introduced according to one or more exemplary examples, it should be understood that each aspect of the disclosure can also constitute a complete embodiment.

[0064] It should be noted that the brief description of the terms in the present application is only for the convenience of understanding the subsequently described embodiments, and is not intended to limit the embodiments of the present application. Unless otherwise specified, these terms should be understood according to their ordinary and general meanings.

[0065] The terms "first", "second", and the like in the description and in the claims of the present application and above-described drawings are used for distinguishing between similar or identical objects and do not necessarily have to indicate a specific order or sequence. It is to be understood that the using of these terms is interchangeable under appropriate circumstances and that the embodiments of the present application can operate in other sequences than described or illustrated herein.

[0066] In addition, the terms "comprise", "comprising", "have", "having", "include", "including" and the like are used in the detailed description and in the claims of the present application to mean either an inclusive process or apparatus that includes one or more components or steps, but does not exclude other components or steps. Similarly, "containing", "containing", "contain" and the like are used in the detailed description and in the claims of the present application to mean an inclusive process or apparatus that includes one or more components or steps, but does not exclude other components or steps.

[0067] The term "module" used in the present application refers to any known or later developed hardware, software, firmware, artificial intelligence, fuzzy logic, or combinations thereof, capable of performing the functions associated with that element.

[0068] Figure 1 Fig. 1 shows a schematic diagram of an operating scenario between a display device and a control device according to an embodiment. As shown in Fig. 1, a user can operate the display device 200 through a mobile terminal 1002 or a control device 1001. Figure 1 As shown in Fig. 1, a user can operate the display device 200 through a mobile terminal 1002 or a control device 1001.

[0069] In some embodiments, the control device 1001 can be a remote controller, and the user can input user instructions through buttons, voice input, control panel input, etc. on the remote controller to control the display device 200.

[0070] As shown in Fig. 1, the display device 200 can be connected to a server 400 through a variety of communication modes. The display device 200 can be allowed to be connected through a local area network (LAN), a wireless local area network (WLAN), and other networks. The server 400 can provide various contents and interactions to the display device 200. Figure 1 As shown in Fig. 1, the display device 200 can be connected to a server 400 through a variety of communication modes. The display device 200 can be allowed to be connected through a local area network (LAN), a wireless local area network (WLAN), and other networks. The server 400 can provide various contents and interactions to the display device 200.

[0071] The display device 200 can be a liquid crystal display, an OLED display, etc. The specific display device type, size, resolution, etc. are not limited, and those skilled in the art can understand that the display device 200 can be changed in performance and configuration as needed.

[0072] As shown in Fig. 1, the display device 200 can be connected to a server 400 through a variety of communication modes. The display device 200 can be allowed to be connected through a local area network (LAN), a wireless local area network (WLAN), and other networks. The server 400 can provide various contents and interactions to the display device 200. Figure 1 As shown in Fig. 1, the display device 200 can be connected to a server 400 through a variety of communication modes. The display device 200 can be allowed to be connected through a local area network (LAN), a wireless local area network (WLAN), and other networks. The server 400 can provide various contents and interactions to the display device 200.

[0073] As an optional connection mode, the camera 201 is connected with the rear shell of the display device through a connecting plate, and is fixedly installed at the upper middle part of the rear shell of the display device 200. As an installable mode, the camera 201 can be fixedly installed at any position of the rear shell of the display device 200, and can ensure that the image acquisition area is not blocked by the rear shell, for example, the image acquisition area is the same as the display direction of the display device 200.

[0074] As another optional connection mode, the camera 201 is connected with the rear shell of the display device through a connecting plate or other conceivable connector, and is liftable. A lifting motor is installed on the connector. When the user wants to use the camera or an application program wants to use the camera, the camera is lifted out of the display device 200. When the camera is not needed, the camera can be embedded behind the rear shell to protect the camera from damage and protect the user's privacy and security.

[0075] When the camera 201 is installed on the display device 200, the content displayed by the display device 200 in different application scenarios can be fused in different modes, thereby achieving functions that cannot be achieved by traditional display devices.

[0076] For example, a user can watch a video program while video chatting with at least one other user. The video program can be presented as a background picture, and a window of the video chat can be displayed on the background picture. This function can be referred to as "chatting while watching" for example.

[0077] In another example, in a motion sensing type game (such as a ball hitting type, a boxing type, a running type, a dancing type, etc.), the human body posture and action are acquired through the camera, the body detection and tracking, the detection of the key point data of the human body skeleton, and the fusion with the animation in the game, thereby realizing a game in a sports, dancing, or the like scene.

[0078] In some other examples, more functions can be added or the above functions can be reduced. The function of the display device is not limited in the present application.

[0079] Figure 2 An exemplary hardware configuration block diagram of the display device 200 according to an exemplary embodiment is shown in the figure.

[0080] In some embodiments, the display device 200 includes at least one of the camera 201, the controller 250, the tuner 210, the communicator 220, the detector 230, the input / output interface 255, the display screen 275, the audio output interface 285, the memory 260, the power supply 290, the user interface 265, and the external device interface 240.

[0081] In some embodiments, the display screen 275 is a component for receiving image signals output from a first processor and for displaying video content and images as well as a menu control interface.

[0082] In some embodiments, the communicator 220 is a component for communicating with external devices or external servers according to various communication protocol types.

[0083] In some embodiments, the user interface 265 can be used to receive infrared control signals from the control device 1001 (e.g., an infrared remote controller).

[0084] In some embodiments, the detector 230 is used by the display device 200 to collect signals from the external environment or to interact with the outside world.

[0085] In some embodiments, the camera 201 can be used to capture external environmental scenes and to capture user attributes or user interaction gestures. It can adaptively change display parameters and recognize user gestures to achieve the function of interaction with the user.

[0086] In some embodiments, such as Figure 2 As shown, the input / output interface 255 is configured to enable data transmission between the controller 250 and other external devices or other controllers 250. This includes receiving video and audio signal data, or command and instruction data, from external devices.

[0087] In some embodiments, the external device interface 240 may include, but is not limited to, one or more interfaces such as an HDMI interface, an analog or high-definition component input interface, a composite video input interface, a USB input interface, and an RGB port. Alternatively, multiple interfaces may be combined to form a composite input / output interface.

[0088] In some embodiments, such as Figure 2 As shown, the tuner / demodulator 210 is configured to receive broadcast television signals via wired or wireless means, and can perform modulation and demodulation processes such as amplification, mixing, and resonance to demodulate audio and video signals from multiple wireless or wired broadcast television signals. The audio and video signals may include television audio and video signals carried in the frequency of the television channel selected by the user, as well as EPG data signals.

[0089] In some embodiments, the controller 250 controls the operation of the display device and responds to user operations via various software control programs stored in memory. The controller 250 can control the overall operation of the display device 200. For example, in response to receiving a user command to select a UI object to display on the display screen 275, the controller 250 can perform operations related to the object selected by the user command.

[0090] As shown in Figure 2 Controller 250 includes at least one of a Random Access Memory (RAM) 251, a Read-Only Memory (ROM) 252, a video processor 270, an audio processor 280, other processors 253 (e.g., a Graphics Processing Unit (GPU), a Central Processing Unit (CPU), a Communication Interface, and a Communication Bus 256. The Communication Bus connects various components.

[0091] In some embodiments, RAM 251 is used to store temporary data of an operating system or other programs running

[0092] In some embodiments, ROM 252 is used to store instructions for various system booting.

[0093] In some embodiments, upon receiving a power-on signal, the power supply of display device 200 starts booting, the CPU runs the system booting instructions in ROM 252, copies the temporary data of the operating system stored in the memory to RAM 251, so as to boot or run the operating system. When the operating system booting is completed, the CPU copies the temporary data of various application programs in the memory to RAM 251, and then boots or runs various application programs.

[0094] In some embodiments, CPU processor 254 is used to execute instructions of the operating system and application programs stored in the memory, and execute various application programs, data and content according to various interactive instructions received from external input, so as to finally display and play various audio and video content.

[0095] Power supply 290, under the control of controller 250, provides power supply support for display device 200 by inputting power from external power supply. Power supply 290 can include a built-in power supply circuit installed inside display device 200, or an external power supply installed outside display device 200, and a power supply interface for providing external power supply in display device 200.

[0096] User interface 265 is used to receive user input signals, and then send the received user input signals to controller 250. The user input signals can be remote control signals received through an infrared receiver, or various user control signals received through a network communication module.

[0097] The memory 260 includes various software modules stored for driving the display device 200. For example, the various software modules stored in the first memory include at least one of a base module, a detection module, a communication module, a display control module, a browser module, and various service modules.

[0098] The base module is a bottom layer software module for signal communication between various hardware in the display device 200 and transmitting processing and control signals to upper layer modules. The detection module is a management module for collecting various information from various sensors or user input interfaces, and performing digital-to-analog conversion and analysis management.

[0099] In some embodiments, when the display device adopts a liftable camera, a pulse width modulation (PWM) signal with a fixed duty cycle is mainly provided by an in system program (ISP) chip to drive the stepping motor to drive the camera module to lift.

[0100] For example, in a feasible embodiment, the display device drives the stepping motor using a PWM fixed 50% duty cycle square wave, and the stepping motor excitation current can only rise from 0 to the maximum positive value in a certain time, then from the maximum positive value to 0, then from 0 to the maximum negative value, and then from the maximum negative value to 0. After completing this process, the stepping motor rotor rotates one step, that is, the rotor advances one angle.

[0101] In the above driving mode, the stepping motor repeatedly adjusts the position at the current position in the low speed state, and vibration noise is generated. In order to better understand the embodiments of the present application, refer to Figure 3 , Figure 3 The figure shows the principle of vibration noise generated by the stepping motor in the embodiments of the present application.

[0102] As Figure 3 shown, in the embodiments of the present application, it is assumed that the rotor needs to rotate to the target position A under the combined force of the two groups of coil magnetic fields. When the rotor rotates to the target position A, it will continue to rotate to position B due to mechanical inertia exceeding the target position A. At this time, since the rotor rotation direction and the magnetic field force direction are opposite, it will reverse and rotate towards the target position A under the action of the magnetic field force; when it rotates to the target position A again, it will continue to rotate to position C due to mechanical inertia. At this time, the rotation direction is opposite to the magnetic field force direction, and it will reverse and rotate again, …, after several swings, it will finally stop at the target position A under the action of friction. This repeated back and forth "swing", forms the vibration of the stepping motor, and thus generates a larger noise.

[0103] In addition, the lifting speed of the camera is related to the frequency of the PWM square wave, and the frequency of the PWM signal for driving the camera to lift is fixed, that is, only a fixed lifting speed can be provided, which brings poor user experience to the user in a relatively quiet environment.

[0104] To solve the above technical problems, in the embodiments of the present application, a display device is provided, which drives the stepping motor in a subdivided manner by inputting an SPWM signal to the stepping motor, so as to reduce the jitter amplitude of the stepping motor in the running process, and further reduce the noise generated by the stepping motor due to the jitter. Meanwhile, the moving speed of the camera in the lifting or lowering process is adjusted by using the data of the camera in the lifting or lowering process collected by the detection assembly, and the noise generated by the camera in the moving process can be further reduced. The following will be described in detail by using detailed embodiments.

[0105] Reference Figure 4 , Figure 4 The structure of the display device 200 in the exemplary embodiments of the present application is shown in Figure 1 In some embodiments, in addition to the camera 201 and the controller 250, the display device 200 is also provided with a stepping motor 301 and a detection assembly.

[0106] The stepping motor 301 is an electric motor that converts an electric pulse signal into a corresponding angular displacement or linear displacement. For each input pulse signal, the rotor rotates an angle or moves forward by one step, and the output angular displacement or linear displacement is proportional to the input pulse number, and the rotation speed is proportional to the pulse frequency.

[0107] In the embodiments of the present application, the stepping motor 301 and the camera 201 are connected, and are used to control the camera 201 to lift or lower along the fixed track.

[0108] In a possible implementation, the detection assembly includes a plurality of Hall devices, and each Hall device is arranged at an equal interval in the moving path of the camera. In addition, the camera 201 is provided with a magnet element 2011.

[0109] The Hall device is a solid-state electronic device that utilizes the Hall effect. When the magnet element 2011 on the camera 201 passes through any Hall device, the Hall device outputs an electric signal in a specific state.

[0110] For example, Figure 4As shown, the detection assembly includes four Hall devices, namely Hall device H1, Hall device H2, Hall device H3, and Hall device H4. Among them, the Hall device H1 is located at the bottom end of the camera moving path, and the Hall device H4 is located at the top end of the camera moving path. When the Hall device H1 outputs an electrical signal of a specific state, it can be considered that the camera 201 has moved to the bottom end of the camera moving path, and when the Hall device H4 outputs an electrical signal of a specific state, it can be considered that the camera 201 has moved to the top end of the camera moving path.

[0111] In another possible implementation, the detection assembly includes a plurality of infrared light receiving devices, each of which is arranged at equal intervals in the moving path of the camera. In addition, the camera 201 is provided with an infrared light emitting device.

[0112] As shown, Figure 5 As shown, Figure 5 Fig. 2 is another structural schematic diagram of the display device 200 in the exemplary embodiment of the present application. Figure 2 The detection assembly includes four infrared light receiving devices, namely infrared light receiving devices P1, P2, P3, and P4, which are arranged in the moving path of the camera in sequence, wherein the infrared light receiving device P1 is located at the bottom end of the camera moving path, and the infrared light receiving device P4 is located at the top end of the camera moving path. When the infrared light receiving device P1 receives the infrared light emitted by the infrared light emitting device 2012 provided on the camera 201, it can be considered that the camera 201 has moved to the bottom end of the camera moving path, and when the infrared light receiving device P4 receives the infrared light emitted by the infrared light emitting device 2012 provided on the camera 201, it can be considered that the camera 201 has moved to the top end of the camera moving path.

[0113] In some embodiments, the position data of the camera during the lifting or lowering process can be obtained by using the data collected by the detection assembly.

[0114] In some embodiments, the detection assembly can further include a sound collecting assembly for collecting noise data of the camera during movement.

[0115] In some embodiments, the controller 250 is connected with the stepping motor 301, and the controller 250 can input an SPWM signal to the stepping motor to drive the stepping motor 301 in a subdivided manner.

[0116] It can be understood that, since the driving signal of the stepping motor is a series of discrete pulse signals, it means that the rotation of the stepping motor is not smooth, and this non-smoothness is particularly obvious at low speed.

[0117] In some embodiments, multiple small steps can be inserted into each step through "interpolation" to make the movement smoother, that is, by subdivision driving, the jitter and noise generated during the operation of the stepper motor can be reduced.

[0118] It's understandable that stepper motors are driven by circulating current through each phase's excitation windings, causing changes in the direction of the internal magnetic field to rotate. Microstepping, on the other hand, controls the current in each phase winding, causing it to rise or fall according to a specific pattern. This creates multiple stable intermediate current states between zero and maximum current, resulting in multiple stable intermediate states for the direction of the resulting magnetic field vector, which rotates according to the microstepping increments. The amplitude of the resulting magnetic field vector determines the stepper motor's torque, and its direction determines the step angle after microstepping, thus improving the stepper motor's angular accuracy and operational smoothness.

[0119] To better understand the embodiments of this application, please refer to... Figure 6 , Figure 6 This is a schematic diagram of a 1 / 8 subdivision current vector synthesis diagram in an exemplary embodiment of this application.

[0120] In this embodiment of the application, a two-phase four-wire stepper motor is used as an example. The stepper motor includes phase A and phase B. Phase A includes drive line "A+" and drive line "A-", and phase B includes drive line "B+" and drive line "B-".

[0121] In one feasible implementation, eight "small steps" can be inserted during the change from the original drive line A+ to drive line B+, making the stepper motor run more smoothly.

[0122] To maintain a constant torque, in this embodiment, an SPWM signal can be input to the stepper motor to make the phase current of each microstep change according to a sinusoidal law. That is, in each microstep, the resultant force of the magnetic field formed by the A and B phase currents on the rotor is equal, and equal to the force when a single coil is fully conducting, thereby enabling the motor to operate in the optimal working state.

[0123] It is understandable that the SPWM signal is based on the PWM signal but with a different modulation pulse mode. Its pulse width and duty cycle are arranged according to a sine wave pattern, so the output waveform can be made into a sine wave output after appropriate filtering.

[0124] It can be understood that the display device is in good condition when it leaves the factory, and the driving performance of the stepping motor is good and the noise is small. However, as the use time of the display device gradually increases, the lead screw of the stepping motor will inevitably be worn to a certain extent, and the lubrication will be insufficient, resulting in an increase in noise during the lifting or lowering of the camera. Among them, the noise is more obvious at the start and end stages of the stepping motor.

[0125] In some embodiments, the controller 250 can obtain various data of the camera 201 during the lifting or lowering process collected by the detection component, and adjust the frequency of the SPWM signal input to the stepping motor 301 according to the obtained data, so as to adjust the moving speed of the camera 201 during the lifting or lowering process.

[0126] In a feasible implementation, the frequency of the SPWM signal can be actively reduced when it is detected that the stepping motor is at the start or end stage, so as to reduce the moving speed of the camera 201 when it just starts to move or is about to stop, thereby achieving the purpose of reducing the noise generated by the camera during the lifting or lowering process.

[0127] In another feasible implementation, the frequency of the SPWM signal can also be actively reduced when it is detected that the noise generated during the movement of the camera is greater than a set threshold, so as to reduce the moving speed of the camera 201, thereby achieving the purpose of reducing the noise generated by the camera during the lifting or lowering process.

[0128] The display device provided by the embodiments of the present application can drive the stepping motor in a subdivided driving manner by inputting the SPWM signal to the stepping motor, so as to make the running process of the stepping motor smoother, thereby reducing the noise generated by the stepping motor due to vibration; at the same time, the data of the camera during the lifting or lowering process collected by the detection component is used to adjust the SPWM signal, so as to adjust the moving speed of the camera during the lifting or lowering process, which can further reduce the noise generated by the camera during the lifting or lowering process.

[0129] In some embodiments, in order to better meet the differentiated needs of different users, the display device 200 can provide multiple moving modes for the user to select.

[0130] For example, the above moving modes can include:

[0131] Standard mode: the camera uses a fixed SPWM signal during the lifting or lowering process. In this mode, the camera can quickly complete the lifting or lowering, but the noise is relatively large. For example, in the standard mode, when driving the camera to lift or lower, a 32KHz SPWM signal is input to the stepping motor throughout the process, so that the camera completes the lifting or lowering at a fixed speed throughout the process.

[0132] The soft mode is that the camera moves at a slow speed at the beginning and the end of the process, and moves at a default speed in the middle process. In this mode, the camera completes the lifting or lowering in a moderate time, and the noise generated in the process is smaller than that in the standard mode. For example, in the soft mode, a 16KHz SPWM signal is input to the stepper motor at the beginning and the end of the lifting or lowering process, and a 32KHz SPWM signal is input to the stepper motor in the middle process.

[0133] The quiet mode is that the camera moves at an optimal speed in the whole process of lifting or lowering. In this mode, the noise generated is the smallest, but the time for the camera to complete the lifting or lowering may be longer, which is suitable for use by the user at night or in a quiet environment.

[0134] In a feasible implementation, when the controller receives an instruction to control the camera to lift or lower, the current moving mode of the camera can be determined first. If the current moving mode of the camera is the standard mode, a SPWM signal with a fixed frequency is input to the stepper motor, so as to quickly control the camera to complete the lifting or lowering. If the current moving mode of the camera is the soft mode or the quiet mode, a SPWM signal with a default frequency value is first input to the stepper motor, and then the frequency value of the SPWM signal is adjusted in real time according to the data collected by the detection assembly in the process of lifting or lowering of the camera.

[0135] In some embodiments, the controller can pre-set a plurality of SWPM signals with different frequency values, such as a default frequency of 32KHz, and optional frequencies including 16KHz, 8KHz and 4KHz. When the default frequency is used, the time for the camera to complete the lifting or lowering is 0.5s, and when the optional frequencies including 16KHz, 8KHz and 4KHz are used respectively, the time for the camera to complete the lifting or lowering is 1.1s, 1.9s and 2.4s respectively.

[0136] In the embodiments of the present application, the user can select a moving mode suitable for himself by comprehensively considering the time for the camera to complete the lifting or lowering and the tolerance of the user to the noise generated in the process of lifting or lowering of the camera.

[0137] The display device provided in the embodiments of the present application can provide a plurality of moving modes of the camera for the user, and the noise generated in each moving mode is different, so that the differentiated needs of different users can be better met.

[0138] In some embodiments, still referring to Figure 4The detection assembly includes a plurality of Hall devices, each of which is arranged at an equal interval in the moving path of the camera; when the controller 250 receives an instruction to control the camera 201 to rise or descend, if it is determined that the current moving mode of the camera 201 is the soft mode, the detection data of each Hall device is acquired, and the current position of the camera 201 is determined according to the detection data of each Hall device.

[0139] For example, when the controller 250 receives an instruction to control the camera 201 to rise, if the Hall device H1 outputs an electrical signal of a specific state, it can be determined that the camera 201 is currently at the bottom end of the moving path; if the Hall device H1 stops outputting the electrical signal of the specific state, and the Hall device H2 has not yet outputted the electrical signal of the specific state, it can be determined that the camera 201 is currently between the Hall device H1 and the Hall device H2; if the Hall device H2 outputs the electrical signal of the specific state, it can be determined that the camera 201 has moved to the position where the Hall device H2 is located……

[0140] In the embodiment of the application, during the rising of the camera 201, the moving path between the Hall device H1 and the Hall device H2 can be determined as the starting section of the camera 201, and the moving path between the Hall device H3 and the Hall device H4 can be determined as the ending section of the camera 201. During the descending of the camera 201, the moving path between the Hall device H4 and the Hall device H3 can be determined as the starting section of the camera 201, and the moving path between the Hall device H2 and the Hall device H1 can be determined as the ending section of the camera 201.

[0141] In a feasible implementation, the controller 250 adjusts the frequency of the SPWM signal from a default frequency value to a first frequency value when it is determined that the camera 201 is in the above-mentioned starting section or ending section, and adjusts the frequency of the SPWM signal back to the default frequency value when it is determined that the camera 201 is between the above-mentioned starting section and ending section.

[0142] In the embodiment of the application, the Hall device H1 and the Hall device H4 can also replace the mechanical limiting structure or the travel switch, and the controller 250 can determine whether the camera 201 has moved to the bottom end or the top end through the signals outputted by the Hall device H1 and the Hall device H4, and stop the camera 201 from moving when it is determined that the camera 201 has moved to the bottom end or the top end, so that the camera 201 can be prevented from making noise by hitting the mechanical limiting structure.

[0143] Optionally, the default frequency value can be 32KHz, and the first frequency value can be any one of 16KHz, 8KHz and 4KHz, which is not limited in the embodiment of the application.

[0144] With reference to Figure 7 , Figure 7 Another structure of the display device 200 in the exemplary embodiments of the present application is shown in FIG. 3B. Figure 3 In some embodiments, a microphone 501 is further arranged in the display device 200 in addition to the camera 201, the controller 250, the stepping motor 301 and the detection assembly. The microphone 501 is configured to collect noise data of the camera 201 during the movement.

[0145] Since the frequency range of the camera 201 during the movement is fixed, the sound collected by the microphone 501 can be filtered according to the frequency range of the camera 201 during the movement, so as to obtain the noise data of the camera 201 during the movement.

[0146] It can be understood that when the display device 200 is just out of the factory, the driving performance of the stepping motor 301 is in good condition, and the noise is small. However, with the daily use of the camera 201, problems such as wear of the lead screw of the stepping motor 301 and insufficient lubrication of the motor may occur, so that the noise of the stepping motor 301 during the lifting process increases.

[0147] In a possible implementation, the controller 250 obtains the noise data collected by the microphone 501 when it is determined that the camera 201 is in the starting section or the ending section. If the decibel value of the noise data is greater than or equal to a preset decibel threshold (such as 35 dB), the frequency of the output SPWM signal is adjusted from a default frequency value to a first frequency value. If the decibel value of the noise data is less than the preset decibel threshold, the frequency of the output SPWM signal is restored to the default frequency value.

[0148] Through the above manner, the embodiments of the present application not only can ensure that the camera does not generate large noise during the lifting process, but also can take into account the length of time for the camera to complete the lifting process.

[0149] In some embodiments, when the controller 250 determines that the currently set movement mode of the camera 201 is the quiet mode, the noise data of the camera 201 during the entire movement process collected by the microphone 501 is obtained in real time. If the decibel value of the currently collected noise data is greater than or equal to a preset decibel threshold, the frequency of the output SPWM signal is adjusted from a default frequency value to a first frequency value. If the decibel value of the noise data is less than the preset decibel threshold, the frequency of the output SPWM signal is restored to the default frequency value.

[0150] Through the above manner, when the currently set movement mode of the camera 201 is the quiet mode, the embodiments of the present application can ensure that the noise decibel value of the camera 201 during the entire movement process is lower than the preset decibel threshold, so as to meet the use requirements of the user in the night or in a quiet environment.

[0151] Refer to Figure 8 , Figure 8 Fig. 7 is a schematic diagram of another structure of the display device 200 in the exemplary embodiments of the present application Figure 4 In some embodiments, in addition to being provided with some or all of the camera 201, the controller 250, the stepping motor 301, the detection assembly, and the microphone 501, the display device 200 is also provided with an H-bridge circuit 601, which is used to provide driving current to the stepping motor 301.

[0152] It can be understood that, in the process of daily use, the camera 201 will have the problem of increased resistance torque of the stepping motor 301 when reaching the same lifting position due to thread wear and tear and insufficient lubrication of the lead screw, and if the driving current of the stepping motor 301 is insufficient, mechanical vibration and noise will occur.

[0153] In a possible implementation, in the process of movement of the camera 201, the controller 250 determines the driving current value provided by the H-bridge circuit 601 to the stepping motor 301; and when the driving current value is greater than a preset current threshold value, the amplitude of the output SPWM signal is adjusted from a default amplitude to a first amplitude.

[0154] Optionally, the default amplitude can be 80% of the full amplitude of the driving of the stepping motor 301, and the first amplitude can be 95% of the full amplitude of the driving of the stepping motor 301.

[0155] In the embodiments of the present application, when the camera 201 is moving, if it is determined that the driving current value output by the H-bridge circuit 601 needs to be increased, the noise and speed loss caused by the increase of the resistance torque of the stepping motor can be effectively reduced by increasing the amplitude of the output SPWM signal.

[0156] In another possible implementation, in the process of movement of the camera 201, the controller 250 determines the moving speed of the camera 201 according to the detection data of each Hall device; and when the moving speed of the camera 201 is less than a preset moving speed corresponding to the input SPWM signal of the stepping motor, the amplitude of the input SPWM signal of the stepping motor is adjusted from a default amplitude to a first amplitude.

[0157] In the embodiments of the present application, when the camera 201 is moving, if it is determined that the moving speed of the camera 201 is lower than the originally set speed, the noise and speed loss caused by the increase of the resistance torque of the stepping motor can also be reduced by increasing the amplitude of the output SPWM signal.

[0158] In some embodiments, after adjusting the amplitude of the output SPWM signal from the default amplitude to the first amplitude described above, if the decibel value of the noise data collected by the microphone 501 is greater than or equal to the preset decibel threshold, the frequency of the output SPWM signal can also be adjusted from the default frequency value to the first frequency value described above, thereby further reducing the noise generated by the camera 201 during movement.

[0159] With reference to Figure 9 , Figure 9 FIG. 7 is a schematic structural diagram of another display device 200 in an exemplary embodiment of the present application. Figure 5 In some embodiments, in addition to being provided with some or all of the camera 201, the controller 250, the stepping motor 301, the detection assembly, the microphone 501, and the H-bridge circuit 601, the display device 200 is also provided with an optical grating ruler 701 for detecting the rotation angle of the stepping motor 301.

[0160] In an embodiment of the present application, a two-phase four-wire stepping motor is taken as an example, the step angle of the two-phase four-wire stepping motor is 18°, and when the stepping motor operates in a “four-tap” control mode, after completing the four-phase current commutation of A+, B+, B-, and A-, the motor rotating shaft advances by one step angle, i.e., rotates by 18°.

[0161] In the traditional working process of the stepping motor 301, the rotation of the rotor is controlled by the PWM wave sent by the main control IC, and in order to ensure that the motor does not “miss steps”, the motor current needs to be controlled in a manner from the maximum positive direction to the maximum negative direction, which increases the motor operating noise.

[0162] In an embodiment of the present application, the controller 250 inputs an SPWM signal to the stepping motor 301 to drive the stepping motor 301 in a subdivision driving manner to reduce noise, but this subdivision driving has the risk of “software missing steps”. That is, the controller 250 has already executed the control instruction, but the camera has not reached the expected position.

[0163] In order to avoid the above error, in a feasible implementation, when the stepping motor 301 drives the camera 201 to move, the rotation angle of the stepping motor detected by the optical grating ruler 701 is obtained; it is determined whether the rotation angle of the stepping motor 301 is the same as the target angle of the stepping motor 301 controlled by the controller 250; if not, the stepping motor is controlled to rotate to the target angle.

[0164] In an embodiment of the present application, the optical grating ruler 701 can be used to accurately control the full-stroke movement position of the camera 201, and realize functions such as half-stroke stopping and arbitrary position stopping.

[0165] With reference to Figure 10 , Figure 10A flowchart of a lifting camera control method provided in an embodiment of the present application. In some embodiments, the lifting camera control method comprises:

[0166] S11. Initialize the SPWM signal.

[0167] S12. Create and initialize the frequency division number, step size, and duty cycle.

[0168] In some embodiments, the SPWM signal can create four basic frequencies, such as 32KHz, 16KHz, 8KHz, and 4KHz. In addition, the step size and duty cycle of the SPWM signal can be customized.

[0169] S13. Start the stepper motor control timer.

[0170] The stepper motor control timer can be used to provide the time constant of the subdivision drive.

[0171] S14. Enable the hardware global interrupt.

[0172] S15. Load the initial value of the stepper motor start step size and the pre-frequency division.

[0173] S16. Start the stepper motor control.

[0174] S17. Determine whether the stepper motor meets the start condition? If yes, continue to S18, if not, continue to wait for the stepper motor to meet the start condition.

[0175] S18. Determine the current movement mode of the camera? If it is the standard mode, execute S19 to S20; if it is the soft mode, execute S21 to S26; if it is the quiet mode, execute S27 to S29.

[0176] S19. Switch the SPWM signal to the basic frequency and keep it unchanged.

[0177] S20. Drive the stepper motor with the current SPWM signal.

[0178] S21. Obtain the detection data of each Hall device, and determine the current position of the camera according to the detection data of each Hall device; adjust the frequency of the SPWM signal according to the current position of the camera.

[0179] S22. Obtain the noise data collected by the microphone, and determine whether the decibel value of the noise data is greater than the preset decibel threshold. If yes, execute S23; if no, execute S24.

[0180] S23. Reduce the frequency of the SPWM signal and return to S22.

[0181] S24. Determine whether the driving current value provided by the H-bridge circuit to the stepping motor is greater than the current threshold value; if yes, execute S25; if no, execute S26.

[0182] S25. Increase the amplitude of the SPWM signal, and return to S24.

[0183] S26. Drive the stepping motor with the current SPWM signal.

[0184] S27. Obtain the noise data collected by the microphone, and determine whether the decibel value of the noise data is greater than the preset decibel threshold value; if yes, execute S28; if no, execute S29.

[0185] S28. Reduce the frequency of the SPWM signal, and return to S22.

[0186] S29. Drive the stepping motor with the current SPWM signal.

[0187] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A display device, characterized by comprising: The application relates to a camera control system, comprising: a camera configured to collect image data; a stepper motor configured to control the camera to rise or fall; a detection component configured to collect data of the camera during the rising or falling process; the detection component comprises a microphone and a plurality of Hall devices; the microphone is used for collecting noise data of the camera during the moving process; each Hall device is arranged equidistantly in a moving path of the camera; a display screen configured to display a user interface and / or image data collected by the camera; a controller connected with the stepper motor, the controller being configured to: input a sinusoidal pulse width modulation (SPWM) signal to the stepper motor to drive the stepper motor in a subdivided manner, the subdivided driving being achieved by inserting a plurality of small steps in each step to make the phase current of the stepper motor change according to a sinusoidal law; and acquire the data of the camera collected by the detection component during the rising or falling process; determine the moving speed of the camera according to the data of the camera collected by the Hall devices during the rising or falling process; adjust the amplitude of the SPWM signal according to the moving speed of the camera to adjust the moving speed of the camera during the rising or falling process, wherein when the moving speed of the camera is less than a preset moving speed corresponding to the currently input SPWM signal of the stepper motor, the amplitude of the currently input SPWM signal of the stepper motor is adjusted from a default amplitude to a first amplitude; the first amplitude is greater than the default amplitude; after the amplitude of the SPWM signal is adjusted from the default amplitude to the first amplitude, if the decibel value of the noise data is greater than or equal to a preset decibel threshold, the frequency of the SPWM signal is adjusted from a default frequency value to a first frequency value, and the first frequency value is less than the default frequency value.

2. The display device of claim 1, wherein, The controller is configured to: determine the currently set moving mode of the camera, the moving mode of the camera comprising a standard mode, a soft mode and a quiet mode; when the currently set moving mode of the camera is the standard mode, the SPWM signal input to the stepper motor is kept unchanged; when the currently set moving mode of the camera is the soft mode or the quiet mode, the SPWM signal is adjusted according to the data of the camera during the rising or falling process.

3. The display device of claim 2, wherein, Each Hall device is arranged equidistantly in the moving path of the camera. The controller is configured to: when the currently set moving mode of the camera is the soft mode, detection data of each Hall device is acquired, and the current position of the camera is determined according to the detection data of each Hall device; the SPWM signal is adjusted according to the current position of the camera.

4. The display device of claim 3, wherein, The controller is configured to: when it is determined that the camera is in a preset starting section or ending section, the frequency of the SPWM signal is adjusted from a default frequency value to a first frequency value; the starting section and the ending section are located at two ends of the moving path of the camera, and the starting section and the ending section have no intersection. The first frequency value is less than the default frequency value. The frequency of the SPWM signal is adjusted to the default frequency value when it is determined that the camera is between the start road segment and the end road segment.

5. The display device of claim 4, wherein, The detection component includes a microphone configured to collect noise data of the camera during movement. The controller is configured to: collect the noise data collected by the microphone when it is determined that the camera is in a preset start road segment or end road segment; adjust the frequency of the SPWM signal from the default frequency value to the first frequency value if the decibel value of the noise data is greater than or equal to a preset decibel threshold value; restore the frequency of the SPWM signal to the default frequency value if the decibel value of the noise data is less than the preset decibel threshold value.

6. The display device of claim 2, wherein, The detection component includes a microphone configured to collect noise data of the camera during movement. The controller is configured to: collect the noise data collected by the microphone in real time when it is determined that the camera is currently set to the quiet mode; adjust the frequency of the SPWM signal from the default frequency value to the first frequency value if the decibel value of the noise data is greater than or equal to a preset decibel threshold value; the first frequency value is less than the default frequency value; restore the frequency of the SPWM signal to the default frequency value if the decibel value of the noise data is less than the preset decibel threshold value.

7. The display device of claim 1, wherein, The detection component includes an H-bridge circuit configured to provide a driving current to the stepper motor. The controller is configured to: determine the driving current value provided by the H-bridge circuit to the stepper motor during movement of the camera; adjust the amplitude of the SPWM signal from a default amplitude to a first amplitude when the driving current value is greater than a preset current threshold value; the first amplitude is greater than the default amplitude.

8. The display device of claim 1, wherein, The detection component includes an optical grating ruler configured to detect the rotation angle of the stepper motor. The controller is configured to: obtain the rotation angle of the stepper motor detected by the optical grating ruler; determine whether the rotation angle of the stepper motor is the same as a target angle of the stepper motor controlled by the controller; control the stepper motor to rotate to the target angle if the rotation angle of the stepper motor is not the same as the target angle.

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