Deicing system and method for hidden handlebar

Abstract

The invention discloses a deicing system and method for a hidden handlebar, and belongs to the technical field of deicing of automobile door handles, and the deicing system comprises a piezoelectric transducer, a high-frequency excitation circuit and a frequency tracking circuit. The deicing system is compact in structure, quick in response, low in energy consumption and high in adaptability; on one hand, the piezoelectric transducer does not need a large heating element, is small in size and light in weight, can be conveniently integrated into the hidden handlebar, and meets the requirements of modern automobiles for attractive appearance and compact design; on the other hand, deicing is achieved by generating shear vibration, compared with a traditional heating mode, the deicing time can be remarkably shortened, the user experience is improved, meanwhile, electric energy is saved, and good energy-saving and environment-friendly performance is achieved; in addition, in the working process of the system, open fire and high heat are avoided, the coating of the automobile body and the material of the handle are not affected, the safety is higher, the service life is longer, and wide application prospects are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of automobile door handle deicing, and in particular to a deicing system and method for concealed vehicle handles. Background Art

[0002] With the arrival of cold weather, hidden car door handles are prone to accumulation of snow and ice, posing potential escape and rescue risks. Traditional de-icing methods rely primarily on physical tools and electric heating systems. De-icing with physical tools is not only cumbersome but can also damage the handle surface. While electric heating systems are effective in removing frost, they also have significant drawbacks. First, electric heating takes a long time to achieve effective de-icing, consumes a lot of energy, and takes up a lot of space during installation. The size of the heating element often presents a challenge, especially in modern compact cars. Second, electric heating devices lack precise temperature control, making it difficult to automatically adjust to the external environment and ice thickness, resulting in wasted energy and incomplete de-icing. Therefore, achieving efficient, fast, accurate, and energy-efficient de-icing technology has become a major challenge in current automotive design.

[0003] In recent years, piezoelectric ceramics have been widely used in sensors and actuators due to their ability to convert electrical and mechanical energy. Within a specific frequency range, particularly at resonant frequencies, piezoelectric ceramics significantly enhance the amplitude of mechanical vibration, reaching peak efficiency in the conversion of electrical and mechanical energy. Therefore, based on the piezoelectric effect of piezoelectric ceramics, the present invention proposes a de-icing system and method for concealed vehicle handlebars. Summary of the Invention

[0004] The technical problem to be solved by the present invention is: how to solve the problems of insufficient power, low efficiency and space occupation of traditional deicing methods, and provide a deicing system for hidden handlebars. It can use the high-frequency vibration characteristics of piezoelectric ceramics without relying on traditional heating elements to effectively and quickly remove ice from the surface of the handlebars.

[0005] The present invention solves the above technical problems through the following technical solutions. The present invention includes a piezoelectric transducer, a high-frequency excitation circuit and a frequency tracking circuit;

[0006] The piezoelectric transducer is installed inside the hidden handlebar and includes a plurality of piezoelectric ceramic pieces, and is used to generate mechanical vibration under the action of the excitation signal of the high-frequency excitation circuit;

[0007] The high-frequency excitation circuit is used to pass an excitation signal to the piezoelectric transducer, so that the piezoelectric transducer operates near the resonant frequency and excites the piezoelectric transducer to generate mechanical vibration, wherein the excitation signal is a high-frequency electrical signal;

[0008] The frequency tracking circuit is used to track and adjust the operating frequency of the piezoelectric transducer so that it remains near the resonant frequency;

[0009] The vicinity of the resonant frequency refers to a frequency range established when the shear stress of the contact surface between the ice layer and the hidden handlebar is greater than a set value.

[0010] Furthermore, the piezoelectric ceramic piece is a planar plate structure, and its shape includes rectangle, frame, disk, ring, triangle, and trapezoid.

[0011] Furthermore, the piezoelectric ceramic sheets are frame-shaped and are an even number, and two adjacent piezoelectric ceramic sheets have opposite polarization directions and are bonded together by conductive silver glue.

[0012] Furthermore, the piezoelectric transducer further includes two groups of electrode sheets, wherein one group of electrode sheets is arranged on one side of the piezoelectric ceramic sheet as a ground terminal, and the other group of electrode sheets is arranged on the other side of the piezoelectric ceramic sheet as a positive electrode.

[0013] Furthermore, the high-frequency excitation circuit includes a high-frequency signal generator, a power amplifier, an impedance matching network and a power management module; the high-frequency signal generator generates a high-frequency electrical signal, the power amplifier amplifies the high-frequency electrical signal, the impedance matching network adjusts parameters to adapt the circuit to the piezoelectric transducer impedance, and the power management module supplies power to the high-frequency signal generator, the power amplifier and the impedance matching network.

[0014] Furthermore, the frequency tracking circuit includes a phase detector, a loop filter, a voltage-controlled oscillator and a feedback network; the phase detector compares the phase difference between the voltage and current signals of the piezoelectric transducer and outputs an error signal; the loop filter filters the high-frequency noise in the error signal and converts it into a smooth control voltage; the voltage-controlled oscillator adjusts the output frequency according to the control voltage so that the frequency of the excitation signal approaches the resonant frequency of the piezoelectric transducer, so that it can meet the condition that the shear stress of the contact surface between the ice layer and the hidden handlebar is greater than 1.2 MPa, and 1.2 MPa is the set value of the contact surface shear stress; the feedback network collects voltage and current signals from the transducer end and sends them back to the phase detector to form a closed-loop regulation.

[0015] The present invention also provides a method for deicing a hidden handlebar, which utilizes the above-mentioned system to complete the deicing of the hidden handlebar, comprising the following steps:

[0016] S1: Install the piezoelectric transducer inside the hidden handlebar;

[0017] S2: Provides an initial excitation signal through the high-frequency excitation circuit to drive the piezoelectric transducer to start working;

[0018] S3: Using a frequency tracking circuit to monitor the working state of the piezoelectric transducer and detect the working frequency of the piezoelectric transducer in real time;

[0019] S4: Using the frequency tracking circuit to adjust the excitation signal frequency of the high-frequency excitation circuit, so that the piezoelectric transducer continuously operates within the optimal resonant frequency range;

[0020] S5: The shear vibration generated by the piezoelectric transducer acts directly on the hidden handlebar, and the generated mechanical energy is used to remove the ice on the surface of the hidden handlebar.

[0021] Compared with the existing technology, the present invention has the following advantages: the deicing system and method for hidden handlebars realizes a deicing system with compact structure, fast response, low energy consumption and strong adaptability; on the one hand, the piezoelectric transducer itself does not require a large heating element, is small in size and light in weight, and is easy to integrate into hidden handlebars, meeting the needs of modern cars for beautiful and compact design; on the other hand, deicing is achieved through vibration, which can significantly shorten the deicing time compared to traditional heating methods, improve user experience, save electricity, and has good energy-saving and environmental protection performance; in addition, there is no open flame or high heat during the operation of this system, and it does not affect the car body coating and handle material. It is safer and has a longer service life, and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a schematic flow chart of a system for deicing concealed vehicle handlebars according to an embodiment of the present invention;

[0023] Figure 2 is a vibration mode diagram of a handlebar covered with ice in an embodiment of the present invention;

[0024] Figure 3 Schematic diagram of the three-dimensional structure and installation position of the piezoelectric transducer in an embodiment of the present invention, wherein (a) is a schematic diagram of the three-dimensional structure of the piezoelectric transducer, and (b) is a schematic diagram of the installation position of the piezoelectric transducer;

[0025] Figure 4 Schematic diagram of the polarization direction of the piezoelectric transducer in an embodiment of the present invention;

[0026] Figure 5 is a schematic diagram of a piezoelectric transducer deicing model according to an embodiment of the present invention;

[0027] Figure 6 is a graph showing the variation of shear stress amplitude with frequency at five randomly selected points on the contact surface under the excitation of the piezoelectric transducer in an embodiment of the present invention;

[0028] Figure 7 is a shear stress distribution diagram of the contact surface of the piezoelectric transducer under optimal frequency excitation in an embodiment of the present invention;

[0029] Figure 8 It is a schematic diagram of the area where the shear stress of the contact surface is greater than 1.2 MPa to achieve the de-icing effect in an embodiment of the present invention.

[0030] In the figure: 1-piezoelectric sheet; 2-piezoelectric sheet; 3-piezoelectric sheet; 4-piezoelectric sheet; 5-electrode sheet; 6-piezoelectric transducer; 7-hidden handlebar; 8-ice layer. DETAILED DESCRIPTION

[0031] The following is a detailed description of an embodiment of the present invention. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process. However, the protection scope of the present invention is not limited to the following embodiment.

[0032] like Figure 1 As shown, the present invention provides a piezoelectric transducer-based system for deicing concealed handlebars, including a piezoelectric transducer, a high-frequency excitation circuit, and a frequency tracking circuit. During deicing, the high-frequency excitation circuit first provides an initial excitation signal to drive the piezoelectric transducer to start working. The frequency tracking circuit monitors the working status of the piezoelectric transducer and detects frequency drift. The frequency tracking circuit adjusts the frequency output of the high-frequency excitation circuit to ensure that the transducer continues to operate near the resonant frequency (wherein, near the resonant frequency refers to the frequency range established when the shear stress of the contact surface is greater than 1.2 MPa). Then, the vibration of the piezoelectric transducer directly acts on the surface of the handlebar, and the generated mechanical energy can be used to remove the ice layer on the handlebar surface.

[0033] The vibration modes of the handlebar covered with ice are analyzed by finite element analysis, such as Figure 2 As shown in the figure, in the plane telescopic mode, the vibration amplitude decreases from the center to the ends. Therefore, a four-frame piezoelectric transducer was designed. The piezoelectric plates in the piezoelectric transducer are mostly located where the amplitude between the handlebars and the ice layer is the largest. By maximizing electromechanical coupling, the piezoelectric transducer outputs higher mechanical energy, achieving a de-icing effect.

[0034] In this embodiment, the piezoelectric transducer structure is as follows: Figure 3 As shown, it consists of four PZT-4 frame-shaped piezoelectric sheets (piezoelectric ceramic sheets) of the same size. The outer frame is 4 cm long and 2 cm wide, the inner frame is 3 cm long and 1 cm wide, the piezoelectric sheet is 0.3 cm thick, and adjacent piezoelectric sheets are bonded with conductive silver glue.

[0035] It should be noted that in the present invention, the piezoelectric sheet can be rectangular, frame-shaped, disc-shaped, ring-shaped, triangular or trapezoidal, etc., to adapt to different structural requirements inside the handlebar. The frame-shaped piezoelectric sheet in this embodiment is only an example of one type.

[0036] The primary function of electrode sheet 5 is to apply an electric field, but it also needs to have other functions, such as heat dissipation. In this embodiment, the electrode sheet 5 above the piezoelectric sheet serves as the positive electrode, while the electrode sheet 5 below the piezoelectric sheet serves as the ground terminal. For economical reasons, electrode sheet 5 is made of brass and is finely polished to form the electrode. The electrode is frame-shaped, with the same dimensions as the piezoelectric sheet: an outer frame of 4 cm long and 2 cm wide, an inner frame of 3 cm long and 1 cm wide, and a thickness of 0.005 cm.

[0037] The polarization direction of the piezoelectric piece is Figure 4 As shown, piezoelectric sheets 1 and 3 are polarized upward along the thickness direction, and piezoelectric sheets 2 and 4 are polarized downward along the thickness direction. The opposite polarization directions of adjacent piezoelectric sheets can improve the shear stress amplitude, modal purity, energy conversion efficiency, and reduce the influence of non-target vibration modes on the target working mode.

[0038] The de-icing model of the piezoelectric transducer is simplified. The simplified piezoelectric transducer and ice layer model are as follows: Figure 5 shown.

[0039] First, the resonance analysis of the entire de-icing structure is performed. In order to find the optimal de-icing frequency, 5 points are randomly selected at the contact surface between the ice layer 8 and the hidden handlebar 7, and the relationship between the shear stress and the frequency is output, as shown in the figure. Figure 6 As shown in the figure, it can be concluded that the optimal resonant frequency for de-icing under the excitation of the piezoelectric transducer is 86.0kHz.

[0040] Under the optimal resonant frequency of 86.0kHz, the shear stress distribution on the contact surface is as follows: Figure 7 As shown. Figure 8 It can be seen that the absolute value of the shear stress in most areas of the contact surface is greater than 1.2 MPa. Figure 6 The maximum stresses in the transducer are 3.16MPa, 1.20MPa, 3.34MPa, 1.88MPa and 4.05MPa respectively. It can be concluded that the transducer is able to remove the ice on the handlebar surface.

[0041] In the present invention, the piezoelectric transducer has multiple possible resonant modes during operation, including but not limited to any of the following: shear vibration mode, transverse length vibration mode, transverse width vibration mode, radial vibration mode, thickness vibration mode, bending vibration mode, torsional vibration mode, and other higher-order vibration modes. By selecting different modes, it is possible to match different structures with deicing objectives. The shear vibration mode in this embodiment is only an example.

[0042] In the present invention, the common structure of the frequency tracking circuit adopts a phase-locked loop (PLL) architecture, which mainly includes a phase detector (PD), a loop filter (LF), a voltage-controlled oscillator (VCO), and a feedback network. The phase detector is responsible for comparing the phase of the voltage signal at the transducer drive end with the current signal at the feedback end. When the transducer deviates from the resonant state, the phase difference between the voltage and current changes, and the phase detector outputs an error signal accordingly; the loop filter filters and amplifies the error signal, converting it into a smooth DC control voltage to eliminate high-frequency noise interference; the voltage-controlled oscillator adjusts the output frequency according to the input control voltage, and outputs a high-frequency excitation signal proportional to the control voltage to drive the transducer; the feedback network collects voltage and current signals from the transducer in real time, providing accurate comparison data for the phase detector. The process is as follows: When the system is operating, the phase detector continuously monitors the phase difference between voltage and current. Once a phase offset occurs, the output error signal is processed by the loop filter and then drives the voltage-controlled oscillator to adjust the output frequency, so that the excitation signal approaches the current resonant frequency of the transducer until the phase difference returns to zero, achieving dynamic frequency tracking. If the resonant frequency of the transducer drifts due to factors such as temperature changes and load fluctuations, the above closed-loop adjustment process will continue to ensure that the transducer always operates in an optimal state. Other control methods that can achieve dynamic frequency adjustment can also be used, such as tracking solutions based on voltage-controlled oscillators (VCOs) or digital frequency synthesizers (DDS).

[0043] In the present invention, the high-frequency excitation circuit is usually composed of core components such as a high-frequency signal generator, a power amplifier, an impedance matching network and a power management module. Among them, the high-frequency signal generator is responsible for generating an electrical signal of a specific frequency to provide an excitation source for the transducer; the power amplifier amplifies the energy of the signal to ensure that there is enough power to drive the transducer to work; the impedance matching network adjusts the circuit parameters to match the amplifier output impedance with the transducer input impedance, reducing signal reflection and energy loss and improving conversion efficiency; the power management module provides a stable DC voltage for each component to ensure stable operation of the circuit. The processing process is as follows: first, the signal generator generates a high-frequency electrical signal, and after the power is enhanced by the power amplifier, the signal transmission is optimized through the impedance matching network, and finally the high-frequency electrical signal is transmitted to the piezoelectric transducer to generate mechanical vibration; according to needs, the circuit may also be equipped with a feedback adjustment mechanism, which dynamically adjusts the excitation signal by real-time monitoring of the amplitude, frequency and other parameters of the output signal to ensure that the transducer works in an efficient state.

[0044] In summary, the de-icing system for hidden handlebars in the above-mentioned embodiment realizes a de-icing system with compact structure, fast response, low energy consumption and strong adaptability; on the one hand, the piezoelectric transducer itself does not require a large heating element, is small in size and light in weight, and is easy to integrate into the hidden handlebars, meeting the requirements of modern cars for beautiful and compact design; on the other hand, de-icing is achieved through vibration, which can significantly shorten the de-icing time compared to traditional heating methods, improve user experience, save electricity, and has good energy-saving and environmental protection performance; in addition, there is no open flame or high heat during the operation of this system, and it does not affect the car body coating and handle material. It is safer and has a longer service life, and has broad application prospects.

[0045] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A de-icing system for a hidden handlebar, characterized in that: Including piezoelectric transducer, high-frequency excitation circuit and frequency tracking circuit; The piezoelectric transducer is installed inside the hidden handlebar and includes a plurality of piezoelectric ceramic pieces, and is used to generate mechanical vibration under the action of the excitation signal of the high-frequency excitation circuit; The high-frequency excitation circuit is used to pass an excitation signal to the piezoelectric transducer, so that the piezoelectric transducer operates near the resonant frequency and excites the piezoelectric transducer to generate mechanical vibration, wherein the excitation signal is a high-frequency electrical signal; The frequency tracking circuit is used to track and adjust the operating frequency of the piezoelectric transducer so that it remains near the resonant frequency; The vicinity of the resonant frequency refers to a frequency range established when the shear stress of the contact surface between the ice layer and the hidden handlebar is greater than a set value.

2. A de-icing system for a hidden handlebar according to claim 1, characterized in that: The piezoelectric ceramic piece is a planar plate structure, and its shape includes rectangle, frame, disk, ring, triangle, and trapezoid.

3. The de-icing system for a hidden handlebar according to claim 1, characterized in that: The piezoelectric ceramic sheets are frame-shaped and are an even number. Two adjacent piezoelectric ceramic sheets have opposite polarization directions and are bonded together by conductive silver glue.

4. The de-icing system for a hidden handlebar according to claim 3, characterized in that: The piezoelectric transducer further comprises two groups of electrode sheets, wherein one group of electrode sheets is arranged on one side of the piezoelectric ceramic sheet as a ground terminal, and the other group of electrode sheets is arranged on the other side of the piezoelectric ceramic sheet as a positive electrode.

5. The de-icing system for a hidden handlebar according to claim 4, characterized in that: The high-frequency excitation circuit includes a high-frequency signal generator, a power amplifier, an impedance matching network and a power management module; the high-frequency signal generator generates a high-frequency electrical signal, the power amplifier amplifies the high-frequency electrical signal, the impedance matching network adjusts parameters to adapt the circuit to the piezoelectric transducer impedance, and the power management module supplies power to the high-frequency signal generator, the power amplifier and the impedance matching network.

6. The de-icing system for a hidden handlebar according to claim 5, characterized in that: The frequency tracking circuit includes a phase detector, a loop filter, a voltage-controlled oscillator, and a feedback network. The phase detector compares the phase difference between the voltage and current signals of the piezoelectric transducer and outputs an error signal. The loop filter filters high-frequency noise in the error signal and converts it into a smooth control voltage. The voltage-controlled oscillator adjusts the output frequency based on the control voltage to bring the frequency of the excitation signal closer to the resonant frequency of the piezoelectric transducer so that it can meet the condition that the shear stress at the contact surface between the ice layer and the hidden handlebar is greater than 1.2 MPa, which is the set value of the contact surface shear stress. The feedback network collects voltage and current signals from the transducer end and sends them back to the phase detector to form a closed-loop regulation.

7. A method for deicing a hidden handlebar, characterized in that: Deicing a hidden handlebar using the system according to any one of claims 1 to 6 comprises the following steps: S1: Install the piezoelectric transducer inside the hidden handlebar; S2: Provides an initial excitation signal through the high-frequency excitation circuit to drive the piezoelectric transducer to start working; S3: Using a frequency tracking circuit to monitor the working state of the piezoelectric transducer and detect the working frequency of the piezoelectric transducer in real time; S4: Using the frequency tracking circuit to adjust the excitation signal frequency of the high-frequency excitation circuit so that the piezoelectric transducer continues to operate near the resonant frequency; S5: The shear vibration generated by the piezoelectric transducer acts directly on the hidden handlebar, and the generated mechanical energy is used to remove the ice on the surface of the hidden handlebar.

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