Vehicle-mounted tail board structure with embedded weighing function and weighing method thereof

Abstract

The invention relates to a vehicle-mounted tail board structure with an embedded weighing function and a weighing method of the vehicle-mounted tail board structure, and relates to the technical field of logistics transportation equipment. The structure comprises a support frame, a force arm, an inclined plate and a hydraulic driving system, a weighing mounting groove in which a weighing assembly is embedded is formed in the middle of the inclined plate, and a scale plate is mounted in the groove in a suspended manner through four pressure sensors and is in communication connection with a central control system; the weighing method comprises the steps of signal acquisition, moving average filtering, weight conversion based on calibration parameters, total weight calculation through weighted summation and overload judgment. The problems that in the prior art, the weighing precision is greatly influenced by structural deformation, and data fluctuation and poor system integration are caused by dynamic interference can be solved.

Description

Technical Field

[0001] This application relates to the field of logistics and transportation equipment technology, specifically to a vehicle-mounted tailgate structure with embedded weighing function and its weighing method. Background Technology

[0002] As a key component of logistics transportation equipment, vehicle-mounted tailgates are widely used in cargo loading and unloading scenarios. Their core function is to achieve the smooth lifting and transfer of goods through a mechanical structure composed of a support frame, lever arm, ramp, and hydraulic drive system. In existing technologies, some vehicle-mounted tailgates integrate weighing functions, primarily using external sensor solutions. Pressure sensors are installed on the external bracket or connecting components of the ramp, and cargo weight data is collected through hydraulic system pressure feedback or an independent weighing platform. The signal is then simply filtered before being transmitted to a display terminal to complete the weighing process.

[0003] However, in existing technologies, the deformation and dynamic disturbance of the inclined plate structure lead to insufficient stability of weighing data, mechanical vibration during cargo loading and unloading causes significant fluctuations in measurement results, and the separation of the sensor and control system architecture increases the complexity of system integration.

[0004] This application provides a vehicle tailgate structure with embedded weighing function and its weighing method, which can solve the technical problems of existing vehicle tailgate weighing functions, such as external sensors being easily damaged, weighing accuracy being greatly affected by structural deformation, and poor system integration.

[0005] To achieve the above objectives, this application provides the following technical solution: This application provides a vehicle tailgate structure with embedded weighing function, including a support frame, a lever arm, a ramp, a lifting cylinder, and a tilting cylinder. The two ends of the lever arm are rotatably connected to the support frame and the ramp, respectively. A crank arm is provided on the lower part of the lever arm near the ramp. The lifting cylinder is located below the lever arm and its two ends are respectively driven and connected to the support frame and the crank arm. A connecting part is provided at the bottom of the ramp. The two ends of the tilting cylinder are respectively driven and connected to the support frame and the connecting part. A weighing mounting groove is provided in the middle of the bearing platform of the ramp. A weighing component is embedded in the weighing mounting groove. The weighing component includes a weighing plate and pressure sensors. The weighing plate is suspended and installed in the weighing mounting groove through four pressure sensors. The signal output terminals of the pressure sensors are communicatively connected to the central control system.

[0006] In one optional embodiment, a sensor mounting base is provided at the bottom of the weighing mounting slot, the lower end of the pressure sensor is fixed to the sensor mounting base by bolts, a sensor pad is provided on the bottom surface of the weighing plate, and the upper end of the pressure sensor is in contact with the force-bearing surface of the sensor pad.

[0007] In one optional embodiment, the sensor mounting base is an inverted U-shaped structure, with both ends fixed to the bottom of the weighing mounting groove of the inclined plate by bolts; the sensor pad is an L-shaped structure, with its horizontal end fixed to the bottom surface of the weighing plate by bolts, and its vertical end in contact with the force-bearing surface of the pressure sensor.

[0008] In one alternative embodiment, the top surface of the weighing plate is flush with the top surface of the inclined plate, and the edge of the weighing plate is provided with a sealing strip, which fills the gap between the weighing plate and the side wall of the weighing mounting groove.

[0009] In one optional embodiment, the central control system includes a microprocessor, a signal conditioning circuit, and a display screen. The input terminal of the signal conditioning circuit is connected to a pressure sensor, and the output terminal is connected to the microprocessor. The communication interface of the microprocessor is connected to the display screen for displaying the weighing results.

[0010] The second aspect of this application provides a weighing method for a vehicle tailgate with embedded weighing function, comprising the following steps: S1: Signal Acquisition. The central control system acquires the analog voltage signals V output by the four pressure sensors in real time through the analog-to-digital converter module. i (i=1,2,3,4, corresponding to the four sensors respectively); S2: Data filtering, the central control system filters the analog voltage signal V. i The moving average filter is applied to remove transient impulse noise, resulting in a stable voltage value V. i ′; S3: Weight conversion. The central control system calculates the weight using the formula W based on pre-stored calibration parameters. i =k×V i ′+b converts the voltage value of each sensor into a local weight value W. i , where k is the calibration coefficient and b is the zero offset; S4: Total weight calculation. The central control system calculates the total weight (W) by weighted summation of the four local weight values. total : , where α i These are the weighting coefficients for each sensor, used to compensate for installation position deviations; S5: Overload detection, central control system will W total Compared with the preset overload threshold T, if W total If >T, the control display will output an overload alarm signal.

[0011] This application provides a vehicle tailgate structure with embedded weighing function and its weighing method. This scheme achieves integrated layout of sensors and main structure by embedding weighing components in the weighing mounting slot in the middle of the inclined plate bearing platform, avoiding direct damage to the sensors from external impacts. The structural design, using a weighing plate with four pressure sensors suspended and installed in the weighing mounting slot, isolates the influence of overall inclined plate deformation on the measurement results, ensuring that the weight of the goods is transmitted to the central control system only through the pressure sensors. Based on the signal output of the pressure sensors, a communication connection to the central control system is established, constructing a complete signal path from data acquisition to processing, eliminating the wiring redundancy of traditional separate architectures. The central control system performs moving average filtering on the analog voltage signal to effectively suppress transient impact noise during loading and unloading, significantly improving the stability of dynamic weighing data. Based on pre-stored calibration parameters, the weighing is achieved using the formula Wi=k×V. i′ +b converts the voltage value into a local weight value, and uses a two-parameter linear model to correct the sensor's nonlinearity error; then, it calculates the total weight by weighting and summing the four local weight values, using a weighting coefficient α. i The design compensates for uneven stress distribution caused by installation position deviations; ultimately, it compares the total weight with a preset threshold to trigger an overload alarm, achieving real-time safety warnings for the weighing results. This design improves the problem of weighing data fluctuations caused by deformation and dynamic interference of the inclined plate structure. At the same time, it enhances the system integration through embedded structure and algorithm fusion, enabling the vehicle-mounted tailgate to achieve high-precision weighing while ensuring loading and unloading functions. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the structure of an embodiment of the present invention / invention; Figure 2 This is a front structural diagram of an embodiment of the present invention / invention; Figure 3 This is a schematic diagram of the internal structure of an embodiment of the present invention / invention. Detailed Implementation

[0013] The technical solutions in the embodiments of this invention / invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this invention / invention, and not all embodiments. Based on the embodiments of this invention / invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention / invention.

[0014] Reference Figure 1 , 2 3. Example

[0015] Existing vehicle-mounted tailgates are mainly used for loading and unloading goods, and typically consist of a bracket, lever arm, ramp, and hydraulic drive system. Although some tailgates have weighing functions, they suffer from technical problems such as externally mounted weighing sensors that are susceptible to impact damage, complex installation, significantly affected weighing accuracy by ramp deformation, resulting in large errors, and separation of sensors from the control system, complicated wiring, and poor system integration.

[0016] Based on the above problems, this application provides a vehicle tailgate structure with embedded weighing function. The bearing platform of the inclined plate (300) is provided with a weighing mounting groove in the middle, and a weighing component (700) is embedded in the weighing mounting groove. The weighing component (700) includes a weighing plate (710) and a pressure sensor (720). The weighing plate (710) is suspended in the weighing mounting groove through four pressure sensors (720). The signal output end of the pressure sensor (720) is communicatively connected to the central control system.

[0017] The weighing mounting groove is a rectangular groove formed in the middle of the inclined plate (300) bearing platform. Its length and width are adapted to the shape of the weighing plate (710). The depth is set according to the thickness of the weighing plate (710), the installation space of the sensor (720) and the compression allowance of the sealing strip (740). It can be set according to the actual situation. An assembly gap is reserved between the groove wall and the edge of the weighing plate (710). This gap is used to accommodate the sealing strip (740) to achieve the functions of dustproof, waterproof and foreign object intrusion prevention. The weighing mounting groove can be processed by CNC milling or laser cutting. The edge of the groove can be chamfered to avoid stress concentration. This application embodiment does not make special limitations on this.

[0018] The weighing component (700) is an integrated embedded weighing unit, which is located inside the inclined plate (300) and does not protrude from the top surface of the inclined plate (300). Its function is to convert the vertical load acting on the weighing plate (710) into an electrical signal and establish a stable communication connection with the central control system through the lead-out cable. The installation position of the weighing component (700) is centrally arranged to match the distribution range of the center of gravity of conventional goods stacking and improve the representativeness of measurement under multi-point load. Its structural layout is coordinated with the direction of the stiffeners of the inclined plate (300) to avoid weakening the main load-bearing path. In this embodiment, the specific installation orientation and fixing method (such as screw connection / snap fastening / adhesion) of the weighing component (700) are not specially limited, as long as it is embedded, stable and detachable for inspection.

[0019] The weighing plate (710) is a rigid flat plate structure used to directly support goods. Its top surface is flush with the top surface of the bearing platform of the inclined plate (300) to ensure a smooth transition of goods without any steps. The material of the weighing plate (710) can be high-strength aluminum alloy, stainless steel or engineering plastic, such as 6061-T6 aluminum alloy or 304 stainless steel. This application embodiment does not make any special limitation on this. Its thickness can be set according to the rated load and stiffness requirements, for example, it can be selected in the range of 12mm to 25mm. Its bottom surface is provided with threaded holes for mounting the sensor pad (730). The hole distribution is consistent with the spatial arrangement of the four pressure sensors (720) and is in an approximately rectangular array. The edge of the weighing plate (710) is provided with a rounded or chamfered structure to reduce the risk of collision and assist the sealing strip (740) to adhere.

[0020] The pressure sensor (720) is an analog output resistance strain gauge pressure sensor with a range of 0–50 kN, a nonlinearity error ≤ ±0.05%FS, and a repeatability error ≤ ±0.02%FS. Four pressure sensors (720) are arranged at the four corners of the bottom diagonal of the weighing plate (710), forming a four-point support layout to balance the load and suppress uneven loading. The lower end of each pressure sensor (720) is fixed to the sensor mounting base (320) with bolts, and the upper end is in contact with the force-bearing surface of the sensor upper pad (730), forming a stable force transmission link. The signal output terminal of the pressure sensor (720) is a standard three-wire system (power positive, power negative, signal output), outputting an analog voltage signal V. i (i=1,2,3,4), its full-scale output voltage is 0~5V or 0~10V. In this application embodiment, there are no special limitations on the specific output amplitude or interface protocol type (such as whether it has a temperature compensation pin), it only needs to be matched with the signal conditioning circuit of the central control system.

[0021] Suspended installation refers to the following: the weighing plate (710) does not directly contact the inclined plate (300) or other rigid structures, but is mechanically connected only through four pressure sensors (720); in the unloaded state, the weighing plate (710) is elastically supported by the sensors (720), and there is a micron-level floating space; when a load is applied, each sensor (720) responds independently to local pressure changes, and its output signal reflects the actual resultant force and torque distribution acting on the weighing plate (710); this installation method makes the weighing plate (710) form a mechanically decoupled subsystem, effectively isolating the bending and torsional deformation of the inclined plate (300) during lifting, flipping and bearing the load from the influence of the balancing result; the realization of suspended installation depends on the elastic deformation characteristics of the sensors (720) themselves and the precise matching of the upper and lower connection interfaces. This application embodiment does not make special restrictions on whether to add auxiliary structures such as limit posts, guide pins or buffer pads.

[0022] The central control system includes a microprocessor, a signal conditioning circuit, an analog-to-digital converter module, a communication interface, and a display screen. The input terminal of the signal conditioning circuit is connected to the signal output terminals of four pressure sensors (720) to complete filtering, amplification, and zero-point calibration. The analog-to-digital converter module converts the conditioned analog voltage signal Vi into a digital quantity. The microprocessor runs the weighing algorithm program to perform data filtering, weight conversion, weighted summation, and overload judgment. The communication interface supports CAN bus or RS485 wired communication and can also integrate Bluetooth / WiFi wireless modules for interaction with the vehicle T-BOX or handheld terminal. The display screen is an industrial-grade LCD screen, installed on the surface of the cab or tailgate control box, for real-time display of weighing results and alarm status. The central control system can be built into the cavity of the support frame (100) or integrated into the back protective cover of the inclined plate (300). The wiring is led to each sensor (720) through the pre-embedded wire groove. This application embodiment does not make special limitations on its physical installation location or power supply method (such as taking from the vehicle battery or independent power module).

[0023] Through the above technical solution, this application achieves the following: when goods are placed on the inclined plate (300) bearing platform, because the weighing plate (710) is flush with the top surface of the inclined plate (300) and the edges are sealed, the goods can be moved in smoothly; the load is evenly transmitted to four pressure sensors (720) through the weighing plate (710), and each sensor independently outputs a corresponding voltage signal V. i The signal is acquired, filtered, calibrated, converted, and weighted by the central control system to obtain a high-precision total weight W. total Since the weighing plate (710) is suspended at four points, its stress state is not affected by the overall deformation of the inclined plate (300), thus overcoming the weighing distortion problem caused by insufficient structural rigidity in the prior art; at the same time, all weighing components are embedded inside the inclined plate (300) to avoid exposure damage, thereby improving the system reliability and environmental adaptability. Example

[0024] In an optional embodiment, this application also provides a vehicle tailgate structure with embedded weighing function. The bottom of the sensor mounting slot is provided with a sensor mounting base (320). The lower end of the pressure sensor (720) is fixed to the sensor mounting base (320) by bolts. The bottom surface of the weighing plate (710) is provided with a sensor upper pad (730). The upper end of the pressure sensor (720) is in contact with the force-bearing surface of the sensor upper pad (730).

[0025] The sensor mounting base (320) is a structural component that supports and precisely positions the lower end of the pressure sensor (720). It is located at the bottom of the weighing mounting groove of the inclined plate (300). Its shape, size and installation position can be adapted to the actual force distribution and spatial constraints. For example, it can be an inverted U-shaped, rectangular block or ring support structure. This application embodiment does not make any special limitation on this. In this embodiment, the sensor mounting base (320) is made of high-strength aluminum alloy material, which has good rigidity and anti-deformation ability. Its two ends are symmetrically fixed to the bottom of the weighing mounting groove by M6 bolts to ensure that the horizontal deviation of the installation plane does not exceed 0.1mm, so as to ensure the consistency of the initial installation posture of the four pressure sensors (720).

[0026] Bolt fixing refers to the rigid connection between the lower mounting flange of the pressure sensor (720) and the sensor mounting base (320) by using standard fastening bolts. The bolt specifications, quantity and preload can be selected according to the model and rated load range of the pressure sensor (720). For example, stainless steel hexagon socket head cap bolts of M4 to M8 specifications can be used in conjunction with anti-loosening washers. The bolt preload is controlled within the range of 5 to 15 N·m to balance connection reliability and prevent the sensor housing from being crushed. This fixing method provides stable support and axial limit for the lower end of the pressure sensor (720), preventing vertical displacement or rotational deflection during dynamic loading and unloading.

[0027] The sensor pad (730) is an intermediate force transmission structure set on the bottom surface of the weighing plate (710) to transmit load and constrain the movement of the upper end of the pressure sensor (720). Its material can be selected according to wear resistance, elastic modulus and processing requirements. For example, it can be wear-resistant polyurethane, engineering plastic (such as POM), copper alloy or surface hardened steel. In this embodiment, the sensor pad (730) is an L-shaped structure. Its horizontal end is fixed to the bottom surface of the weighing plate (710) by M5 countersunk bolts. The vertical end face is treated by surface grinding with a roughness Ra≤1.6μm to ensure full contact with the upper force-bearing surface of the pressure sensor (720). This structure can effectively disperse the concentrated load transmitted by the weighing plate (710) and suppress the lateral component force caused by the local micro deformation of the weighing plate (710).

[0028] The upper end of the pressure sensor (720) is in contact with the force-bearing surface of the upper pad (730) of the sensor, which means that the contact surfaces of the two maintain a surface contact state without gaps or warping under no-load conditions; the contact area is not less than 80% of the pressure-bearing surface of the upper end of the sensor, and the parallelism error of the contact surface is not greater than 0.05mm; when the weighing plate (710) bears the load of the goods, this contact relationship ensures that the pressure sensor (720) only bears pure compressive force along its sensitive axis direction, avoiding the introduction of measurement errors by bending moment, shear force or torsional force; the contact state can be confirmed by applying a slight pre-pressure during assembly and checking with a feeler gauge.

[0029] "Bidirectional limiting and fixing" is the structural effect formed by the synergistic action of the sensor mounting base (320) and the upper pad (730) of the sensor: the sensor mounting base (320) provides downward axial constraint and lateral positioning, and the upper pad (730) of the sensor provides upward reaction support and vertical limiting. Together, they restrict the degree of freedom of the pressure sensor (720) in the Z direction (perpendicular to the surface of the inclined plate) and suppress the X / Y direction sway, thereby ensuring that it is always in the ideal axial pressure working state.

[0030] Through the above technical solution, this application realizes the bidirectional mechanical limiting and precise positioning of the pressure sensor (720), so that the four pressure sensors (720) can maintain a consistent force direction and contact state when the inclined plate (300) is bent or subjected to impact vibration. Since the sensor mounting base (320) and the sensor pad (730) form a rigid clamp on the sensor from the bottom and top respectively, the zero drift and linear error caused by loose installation, poor contact or off-center load are significantly reduced, thereby improving the repeatability and long-term stability of the weighing data and meeting the accuracy requirement of ±0.5%FS under vehicle working conditions. Example

[0031] In one optional embodiment, the present application also provides that the sensor mounting base (320) is an inverted U-shaped structure, and its two ends are fixed to the bottom of the weighing mounting groove of the inclined plate (300) by bolts; the sensor pad (730) is an L-shaped structure, and its horizontal end is fixed to the bottom surface of the weighing plate (710) by bolts, and its vertical end is in contact with the force-bearing surface of the pressure sensor (720).

[0032] The sensor mounting base (320) has an inverted U-shaped structure with its opening facing downwards and both ends extending upwards to form mounting ears. Each of the two mounting ears has a through hole for inserting bolts to rigidly fix the sensor mounting base (320) to the bottom of the weighing mounting groove of the inclined plate (300). The inverted U-shaped structure partially wraps around the pressure sensor (720) in the transverse direction and provides upward support reaction force in the longitudinal direction, thereby enhancing the overall bending stiffness of the mounting base and suppressing warping or torsional deformation during the load-bearing process. The material of the inverted U-shaped structure can be high-strength aluminum alloy or Q345B low-alloy structural steel, and its wall thickness can be set to 3mm to 6mm according to the actual load requirements. This application embodiment does not make any special limitation on this.

[0033] The sensor pad (730) has an L-shaped structure, including a horizontal end and a vertical end that are perpendicularly connected to each other. The horizontal end is provided with a threaded hole and is fastened to the bottom surface of the weighing plate (710) by a countersunk bolt to ensure that there is no relative displacement between the pad and the weighing plate (710). The end face of the vertical end is a flat force-bearing surface, which is completely in contact with the upper force-bearing surface of the pressure sensor (720) to realize the stable transmission of pressure along the vertical direction. The corner of the L-shaped structure is provided with an arc transition with a radius of R2 to R5 to alleviate stress concentration. The material of the sensor pad (730) can be wear-resistant polyurethane, engineering plastic or stainless steel. Its height can be set to 10mm to 25mm according to the stroke margin and assembly tolerance requirements of the pressure sensor (720). This application embodiment does not make any special limitation on this.

[0034] The inverted U-shaped sensor mounting base (320) and the L-shaped sensor upper pad (730) work together to form a pair of rigid-flexible coupled constraint support systems: the mounting base (320) provides bottom rigid limit and lateral constraint, and the upper pad (730) provides top positioning and vertical force transmission path. Together, they ensure that the four pressure sensors (720) are always under axial pressure under dynamic loading and unloading conditions, avoiding lateral load or tilt instability. In one optional embodiment, the width of the inverted U-shaped opening of the sensor mounting base (320) is slightly larger than the width of the pressure sensor (720) body by 0.3mm to 0.8mm, so as to facilitate assembly and centering and reserve thermal expansion and contraction allowance. In another optional embodiment, a micro-protrusion or guide slope can be provided on the inner side of the vertical end of the sensor upper pad (730) to assist the pressure sensor (720) in automatically correcting its center position during installation.

[0035] Through the above technical solution, this application realizes the structural adaptation between the inverted U-shaped sensor mounting base and the L-shaped sensor pad, so that the sensor mounting base has higher bending stability and the sensor pad has better installation convenience and force consistency. The two work together to effectively suppress the non-axial force problem of the sensor caused by local deformation of the inclined plate (300), assembly error or dynamic impact, thereby improving the long-term measurement stability and repeatability of the embedded weighing component (700) in the real working environment of the vehicle tailgate. Example

[0036] In an optional embodiment, the present application also provides that the top surface of the weighing plate (710) is flush with the top surface of the inclined plate (300), and the edge of the weighing plate (710) is provided with a sealing strip, which fills the gap between the weighing plate (710) and the side wall of the weighing mounting groove.

[0037] The fact that the top surface of the weighing plate (710) is flush with the top surface of the inclined plate (300) means that after assembly, the plane on the upper surface of the weighing plate (710) and the plane on the upper surface of the inclined plate (300) bearing platform are at the same height reference, and there is no step difference between them. This flush state can be achieved by adjusting the pre-compression amount of the pressure sensor (720), the thickness of the pad (730) on the sensor, or the installation height of the sensor mounting base (320). The specific parameters can be set according to the actual machining tolerance and assembly requirements. This application embodiment does not make any special limitations on this.

[0038] The sealing strip is made of an elastomer material, such as ethylene propylene diene monomer (EPDM), silicone rubber, or thermoplastic polyurethane (TPU), with a Shore hardness of 40A to 70A. The cross-sectional shape can be rectangular, D-shaped, P-shaped, or lip-shaped to adapt to different gap sizes and compression deformation requirements. The sealing strip is continuously arranged along the circumference of the weighing plate (710), with the two ends butted or overlapped to ensure no breaks. The installation method can be embedded (pre-installed in the groove reserved on the edge of the weighing plate (710)) or adhesive (adheded to the bottom surface of the weighing plate (710) near the edge by double-sided adhesive or structural adhesive). The specific form can be selected according to the dustproof and waterproof level requirements and maintenance convenience. This application embodiment does not make any special limitations on this.

[0039] The sealing strip fills the gap between the weighing plate (710) and the side wall of the weighing installation groove. This means that after the weighing plate (710) is installed in place, the sealing strip is radially compressed and deformed by the pressure of the side wall of the groove, forming an interference fit, thereby constructing a continuous and closed physical barrier between the weighing plate (710) and the weighing installation groove. The width of the gap can be set to 0.3mm to 1.5mm according to the thermal expansion and contraction characteristics of the inclined plate (300) material and the mechanical vibration conditions. The compression rate of the sealing strip is controlled within the range of 20% to 50% to take into account both sealing reliability and long-term resilience performance. In the environment of frequent lifting, bumping and temperature and humidity changes of the vehicle tailgate, this structure can effectively prevent dust, water vapor, debris and cleaning fluid from entering the interior of the weighing installation groove, and avoid contamination, corrosion or foreign object jamming of the contact surface of the pressure sensor (720).

[0040] Through the above technical solution, this application achieves the following: because the top surface of the weighing plate (710) and the top surface of the inclined plate (300) are kept flush, the risk of scratching during cargo dragging and the dead corner of foreign object accumulation are eliminated; at the same time, the sealing strip elastically fills the gap between the two under pressure, forming a stable and reliable physical barrier, thereby solving the technical problem of sensor jamming, corrosion or measurement interference caused by foreign objects, dust and moisture entering the weighing installation slot, and improving the environmental adaptability and long-term weighing stability of the vehicle tailgate under harsh working conditions such as high humidity, dust and open-air operation. Example

[0041] In one optional embodiment, this application also provides a central control system including a microprocessor, a signal conditioning circuit and a display screen. The input terminal of the signal conditioning circuit is connected to a pressure sensor (720), and the output terminal is connected to the microprocessor. The communication interface of the microprocessor is connected to the display screen for displaying the weighing results.

[0042] The central control system is an integrated embedded control unit. Its physical form is a printed circuit board (PCB), which is installed in the electrical compartment reserved inside the support frame (100). It has an IP65 protection rating and can adapt to vehicle vibration, temperature and humidity changes and electromagnetic interference environment. The microprocessor is a 32-bit microcontroller with an ARM Cortex-M4 core and a main frequency of no less than 120MHz. It has a built-in 12-bit analog-to-digital converter (ADC), a hardware floating-point unit (FPU), and a UART / SPI / I²C multi-channel communication interface. It is used to execute the signal acquisition, filtering, conversion, weighted summation, and overload judgment logic as described in Example 6. The signal conditioning circuit includes an instrumentation amplifier, a second-order active low-pass filter, and a programmable gain amplifier cascaded in sequence. Its input is connected to the analog voltage output of four pressure sensors (720) via shielded twisted-pair cables, with an input impedance ≥10Ω. 9 Ω, common-mode rejection ratio ≥100dB, bandwidth set to 0.1Hz~10Hz, used for differential amplification, noise suppression and amplitude adaptation of weak millivolt-level signals output by the sensor, so that the output signal is stabilized in the range of 0~3.3V, meeting the input range requirements of the microprocessor ADC; The display screen is a 2.8-inch TFT LCD screen with a resolution of 240×320. It supports touch feedback and is connected to the microprocessor communication interface via SPI bus. Its display content includes real-time total weight value (unit: kg), single sensor weight distribution bar chart, overload status indicator icon and system working status prompt information. The microprocessor's communication interface also includes one RS485 interface and one Bluetooth 5.0 wireless module. The RS485 interface is used to connect to the vehicle CAN bus gateway to upload weighing data to the vehicle management system (TMS); the Bluetooth module supports pairing with a mobile terminal APP for on-site parameter configuration, historical data export and alarm push. Opto-isolation devices are installed between the signal conditioning circuit and the microprocessor to block ground loop interference; key signal traces on the PCB are designed with equal length and grounded; power and ground layers are split to reduce crosstalk between high-frequency digital signals and analog signal paths. The central control system operates at DC12V and is powered by the vehicle battery through a DC-DC voltage regulator module. The voltage regulator module outputs ripple ≤10mV to ensure clean power supply to the analog front end. Its power consumption is ≤1.2W. In standby mode, it can enter a low-power sleep state with a wake-up response time of <100ms.

[0043] Through the above technical solution, this application achieves the following: the weak and easily interfered analog voltage signal output by the pressure sensor (720) is amplified and filtered with a high signal-to-noise ratio by the signal conditioning circuit, and then converted into digital signals and processed by the microprocessor. Finally, the weighing result is presented intuitively on the display screen. At the same time, data communication with the vehicle system and mobile terminal is realized by using a standardized communication interface, which not only ensures the accuracy and stability of the weighing data, but also improves the efficiency of human-computer interaction and the system integration, effectively solving the technical problems of weak signal, poor anti-interference ability and inability to display locally in the prior art. Example

[0044] The technical problem to be solved by this invention is the large fluctuation, high error, and lack of effective filtering and intelligent judgment of the weighing signal during dynamic loading and unloading.

[0045] A weighing method for a vehicle tailgate with embedded weighing function includes the following steps: Step 1: Signal Acquisition. The central control system acquires the analog voltage signals V output by the four pressure sensors (720) in real time through the analog-to-digital converter module. i (i=1,2,3,4, corresponding to the four sensors respectively); Among them, "signal acquisition" is a newly added technical feature, which refers to the central control system synchronously digitizing four analog voltage signals at a fixed sampling period; the input source for this action is the continuous analog electrical signal output by the pressure sensor (720), and the output result is a discrete digital voltage sequence {V i,1 V i,2 The technical purpose is to provide the raw data foundation for subsequent filtering and conversion; In one optional implementation, the signal acquisition method can be: the central control system is configured with a four-channel synchronous sampling ADC module, the sampling frequency is set to 200Hz, and each acquisition is triggered by an internal timer interrupt to ensure that the four signals are time-aligned; In another alternative implementation, the signal acquisition method may include: the central control system uses an ADC peripheral with DMA transfer function to automatically move the data to the ring buffer after completing a single four-channel conversion, thereby avoiding CPU polling overhead; Furthermore, the signal acquisition method can also adopt the following approach: based on a hardware trigger synchronization mechanism, an external photoelectric switch detects the instant the goods contact the weighing plate (710) and sends out a pulse signal, which serves as the hard trigger source for the ADC to start acquisition, thereby achieving "on-demand acquisition" and reducing data redundancy during idle periods; This application ensures that the raw data has temporal consistency and event correlation through synchronous, high-frequency, and trigger-controllable signal acquisition, providing high-quality input for subsequent moving average filtering, thereby supporting the timeliness of response and data integrity in the dynamic weighing process.

[0046] Step 2: Data filtering, the central control system filters the analog voltage signal V. i The moving average filter is applied to remove transient impulse noise, resulting in a stable voltage value V. i ′; Among them, "moving average filtering" is a newly added technical feature, which refers to calculating the local mean point by point for each voltage signal sequence according to a fixed window length to form a smoothed output sequence; the input source for this action is the aforementioned digital voltage sequence, and the output result is the filtered voltage value V. i The technical objective is to suppress millisecond-level spike noise caused by cargo falling, hydraulic shock, or vehicle bumps during loading and unloading. In one alternative implementation, the moving average filtering method can be: setting the sliding window length to 7 points, taking the arithmetic mean of the current sampling point and its previous 6 historical sampling points, updating the window and outputting a new mean value each time a new point is added; In another alternative implementation, the moving average filtering method may include: using a weighted moving average, assigning a weight of 0.4 to the three newest sampling points in the window, a weight of 0.2 to the two middle points, and a weight of 0.1 to the two oldest points, thus balancing response speed and noise suppression capability; Furthermore, this moving average filtering method can also adopt the following approach: adaptively adjusting the window length in conjunction with the signal change rate—when the voltage change rate of 5 consecutive points exceeds the threshold ΔV / Δt, the window length is dynamically shortened from 7 points to 3 points to improve the tracking capability of sudden loads; This application uses a moving average filter to independently execute the four signals, which preserves the differences in the response characteristics of each sensor while uniformly eliminating common-mode impulse interference, providing a stable and reliable voltage reference for weight conversion and significantly reducing the risk of misjudgment caused by transient disturbances.

[0047] Step 3: Weight conversion. The central control system calculates the weight using the formula W based on pre-stored calibration parameters. i =k×V i ′+b converts the voltage value of each sensor into a local weight value W. i , where k is the calibration coefficient and b is the zero offset; Among them, "weight conversion", "calibration coefficient k", and "zero-point offset b" are all new technical features. "Weight conversion" refers to the process of mapping the filtered voltage to the physical weight dimension based on the linear model. "calibration coefficient k" represents the weight sensitivity corresponding to a unit voltage, which means the weight increment represented by each volt change in voltage. "Zero-point offset b" represents the equivalent weight compensation value corresponding to the non-zero voltage output of the system under no-load conditions. The three together constitute a two-parameter linear calibration model. The technical purpose is to establish a reproducible and traceable quantitative relationship between voltage and weight. Among them, "local weight value W" i "This is a newly added technical feature, referring to the component weight of the area corresponding to its installation location that is sensed and calculated by a single pressure sensor (720). Its physical meaning is the static equivalent mass of the load borne by the sensor; In one alternative implementation, the weight conversion method can be: the central control system pre-stores four independent (k) sets of data in the Flash memory. i ,b i The parameters correspond to four pressure sensors (720), and floating-point operations are performed by calling the corresponding channel parameters each time a conversion is performed. In another alternative implementation, the weight conversion method may include: the central control system employing a lookup table interpolation method—pre-generating a voltage-weight mapping lookup table (LUT) with an entry interval of 0.01V, for V... i Perform linear interpolation to obtain W i This reduces the floating-point operation load on the MCU. Furthermore, this weight conversion method can also be implemented by: the central control system supporting one-click on-site calibration—selecting "no-load calibration" and "full-load calibration" modes via the display menu, automatically collecting the average values ​​of two sets of voltages and calculating and updating k in real time. i With b i Write to the non-volatile memory area; This application, by configuring independent calibration parameters for each sensor and employing a field-updable two-parameter linear model, balances manufacturing tolerance compensation with long-term zero-point drift correction capabilities, thereby improving the local weight value W. i It has channel-level accuracy assurance, providing a reliable foundation for subsequent weighted summation.

[0048] Step 4: Total weight calculation. The central control system performs a weighted sum of the four local weight values ​​to calculate the total W. total : , where α i These are the weighting coefficients for each sensor, used to compensate for installation position deviations; Among them, "weighted summation" and "weight coefficient α" i"Compensation for installation position deviation" is a newly added technical feature; "Weighted summation" refers to a mathematical operation that superimposes the local weight values ​​of the four channels according to a preset ratio; "Weight coefficient α" i "A dimensionless value, representing the relative importance of each sensor in the total weight contribution; "Compensation for installation position deviation" refers to correcting the non-uniformity of stress response caused by uneven spatial distribution of sensors on the inclined plate (300), structural stiffness gradient, or difference in force transmission path of lever arm through differential weighting. In one optional implementation, the weighted summation method can be: the central control system determines the initial weight set through static loading tests before leaving the factory, for example (α1,α2,α3,α4)=(0.23,0.27,0.26,0.24), and fixes it in the configuration area; In another alternative implementation, the weighted summation method may include: the central control system supporting user-defined weights—four sets of normalized coefficients input via touchscreen (satisfying...) The system takes effect and saves the changes in real time. Furthermore, this weighted summation method can also be implemented by: the central control system dynamically generating weights based on the installation structure parameters—reading the center coordinates of the sensor mounting base (320) and the centroid coordinates of the inclined plate (300), and using the lever principle to inversely deduce the theoretical load distribution ratio to generate the initial α. i Then, after further testing and fine-tuning; This application introduces a weighting coefficient α. i By weighting and fusing local weight values, the traditional assumption of equal weight summation is broken, and systematic measurement errors caused by mechanical installation geometric deviations and structural stress field distortions are effectively corrected, so that the total weight calculation results more accurately reflect the overall mass distribution of the cargo.

[0049] Step 5: Overload detection; the central control system will... total Compared with the preset overload threshold T, if W total If >T, the display screen will output an overload alarm signal; Among them, "overload judgment", "preset overload threshold T" and "alarm signal output" are all new technical features; "overload judgment" refers to the decision-making action of logically comparing the calculated total weight with the safety limit; "preset overload threshold T" is a configurable value in kilograms, and its setting is based on the vehicle's rated load capacity and the legally allowed redundancy range; "alarm signal output" refers to the central control system sending instructions to the display screen to trigger visual warnings (such as red flashing text and icons) and optional audio and visual prompts; In one alternative implementation, the overload detection method can be: the central control system adopts a single threshold comparison strategy, when W... total If the overload condition persists for more than 200ms, confirm the overload and lock the alarm status. In another alternative implementation, the overload detection method may include: the central control system introducing a hysteresis comparison mechanism—setting an upper limit threshold T. on =T and lower threshold T off =T−5kg, only when W total An alarm is only triggered when the temperature rises above the limit; it is triggered when the temperature drops to T. off The following steps will be taken to prevent false alarms due to critical point jitter. Furthermore, this overload judgment method can also employ: enhancing judgment reliability through central control system linkage with multi-source information—before triggering the alarm, synchronously verifying whether the four local weight values ​​are all greater than 10% of their respective ranges, and V i The fluctuation range is less than ±0.5%FS, ruling out misjudgment caused by single point of failure; This application, by setting configurable thresholds, introducing time confirmation and hysteresis logic, and supplementing it with multi-channel consistency verification, enables overload judgment to be both sensitive, robust, and practical for engineering, effectively fulfilling the function of transportation safety early warning.

[0050] This application constructs a full-process weighing method for the dynamic working conditions of vehicle tailgates through the coordinated operation of five stages: signal acquisition, moving average filtering, dual-parameter weight conversion, weighted total weight calculation, and closed-loop overload judgment. First, the original sensor signal is captured synchronously at high frequency. Then, transient impact noise is suppressed through moving average filtering. Next, a channel-independent linear calibration model is used to accurately map voltage to local weight. Furthermore, spatial weighting coefficients are used to compensate for installation deviations to improve total weight accuracy. Finally, a safe closed-loop is achieved through overload judgment with hysteresis and verification mechanisms. This method does not rely on external devices or complex models; all calculations are completed locally in the central control system, meeting the requirements of real-time performance, reliability, and low power consumption in the vehicle environment. It effectively solves the technical problems of large fluctuations, high errors, and lack of effective filtering and intelligent judgment in weighing signals during dynamic loading and unloading processes.

[0051] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A vehicle tailgate structure with embedded weighing function, comprising a support frame (100), a lever arm (200), an inclined plate (300), a lifting cylinder (400), and a flipping cylinder (500), wherein the two ends of the lever arm (200) are rotatably connected to the support frame (100) and the inclined plate (300), a crank arm (210) is provided below the lever arm (200) near the inclined plate (300), the lifting cylinder (400) is located below the lever arm (200) and its two ends are respectively driven to connect the support frame (100) and the crank arm (210), a connecting part is provided at the bottom of the inclined plate (300), and the two ends of the flipping cylinder (500) are respectively driven to connect the support frame (100) and the connecting part, characterized in that: The inclined plate (300) has a weighing mounting slot in the middle of its bearing platform, and a weighing component (700) is embedded in the weighing mounting slot. The weighing component (700) includes a weighing plate (710) and a pressure sensor (720). The weighing plate (710) is suspended in the weighing mounting slot by four pressure sensors (720), and the signal output end of the pressure sensor (720) is communicatively connected to the central control system.

2. The vehicle tailgate structure with embedded weighing function according to claim 1, characterized in that: The bottom of the weighing installation slot is provided with a sensor mounting base (320). The lower end of the pressure sensor (720) is fixed to the sensor mounting base (320) by bolts. The bottom surface of the weighing plate (710) is provided with a sensor upper pad (730). The upper end of the pressure sensor (720) is in contact with the force-bearing surface of the sensor upper pad (730).

3. The vehicle tailgate structure with embedded weighing function according to claim 1, characterized in that: The sensor mounting base (320) has an inverted U-shaped structure, and its two ends are fixed to the bottom of the weighing mounting groove of the inclined plate (300) by bolts; the sensor pad (730) has an L-shaped structure, and its horizontal end is fixed to the bottom surface of the weighing plate (710) by bolts, and its vertical end is in contact with the force-bearing surface of the pressure sensor (720).

4. The vehicle tailgate structure with embedded weighing function according to claim 1, characterized in that: The top surface of the weighing plate (710) is flush with the top surface of the inclined plate (300). The edge of the weighing plate (710) is provided with a sealing strip, which fills the gap between the weighing plate (710) and the side wall of the weighing mounting groove.

5. A vehicle tailgate structure with embedded weighing function according to claim 1, characterized in that: The central control system includes a microprocessor, a signal conditioning circuit, and a display screen. The input terminal of the signal conditioning circuit is connected to a pressure sensor (720), and the output terminal is connected to the microprocessor. The communication interface of the microprocessor is connected to the display screen to display the weighing results.

6. A weighing method for a vehicle tailgate with embedded weighing function, characterized in that, Includes the following steps: S1: Signal Acquisition. The central control system acquires the analog voltage signals V output by the four pressure sensors (720) in real time through the analog-to-digital converter module. i (i=1,2,3,4 correspond to four sensors respectively); S2: Data filtering, the central control system filters the analog voltage signal V. i The moving average filter is applied to remove transient impulse noise, resulting in a stable voltage value V. i ′; S3: Weight conversion. The central control system calculates the weight using the formula W based on pre-stored calibration parameters. i =k×V i ′+b, converting the voltage value of each sensor into a local weight value W. i , where k is the calibration coefficient and b is the zero offset; S4: Total weight calculation. The central control system calculates the total weight (W) by weighted summation of the four local weight values. total : ， Where a i These are the weighting coefficients for each sensor, used to compensate for installation position deviations; S5: Overload detection, central control system will W total Compared with the preset overload threshold T, if W total If >T, the control display will output an overload alarm signal.

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