Wide-range precision compound weighing sensor

Abstract

The utility model discloses a wide area precision composite weighing sensor and control method thereof, contain coaxial arrangement's first weighing unit and second weighing unit, realize the contact or separation of container tray and first weighing unit through actuating mechanism drive lifting support assembly, and control unit is based on target weight and position signal intelligent determination mode, carries out signal fusion and drift compensation in range transition area, realizes the continuous high accuracy measurement in full range range, and system has overload and not in place protection, compact structure, switching reliable, strong protection, is applicable to automatic batching and precision manufacturing etc. scene.

Description

Technical Field

[0001] This utility model belongs to the technical field of weighing machinery and equipment, and relates to a wide-range precision composite weighing sensor. Background Technology

[0002] In existing weighing equipment, to meet the combined requirements of wide weighing range and high precision, multiple independent sensors are typically used to handle different weighing ranges. For example, electromagnetic force sensors or strain gauge sensors are used for small-range weighing, while load cells with higher structural strength are used for large-range weighing. However, this approach has the following problems: Complex structure: Multiple sensors are installed independently, resulting in large device size and loose layout, which is not conducive to integration and miniaturization; Unreliable switching: The mechanical switching mechanism has gaps or is not in place, which affects the weighing accuracy and repeatability; Insufficient protection: Small-range sensors are easily damaged by misoperation or overload under heavy load conditions; Signal interference: When multiple sensors work in parallel, they are prone to mutual interference, which affects signal stability and accuracy.

[0003] Therefore, there is a lack of a composite weighing sensor in the existing technology that is compact, has reliable switching, and can achieve high-precision measurement over a wide range. Summary of the Invention

[0004] To address the aforementioned problems, this invention provides a wide-range precision composite weighing sensor. This weighing sensor has a compact structure and high integration, enabling it to meet the requirements of high-precision measurement of small weights while also possessing stable load-bearing capacity for large weights.

[0005] According to the technical solution of this utility model: a wide-range precision composite weighing sensor, characterized in that: it includes a weighing module base and a second weighing unit installed on the weighing module base, wherein the first weighing unit and the second weighing unit are arranged coaxially in the vertical direction; The output end of the actuator is connected to the lifting support assembly to drive the container pallet to rise or fall, thereby enabling the container pallet to contact or separate from the first weighing unit; The control unit automatically determines the metering mode based on the target weight, outputs control signals to drive the actuator to operate, and only collects the weighing unit signal corresponding to the current mode for weighing calculation.

[0006] As a further improvement of this utility model, the actuator is any one of an electric push rod, a servo linear actuator, a pneumatic actuator, or a hydraulic actuator.

[0007] As a further improvement of this utility model, a position sensor is installed at the output end of the actuator. The position sensor is a limit switch, photoelectric encoder, displacement sensor or force / pressure contact type position detector.

[0008] As a further improvement of this utility model, the lifting support assembly includes a lower container support frame and an upper container support frame, which are positioned at intervals by a number of connecting screws and sleeves.

[0009] As a further improvement of this utility model, the weighing module base includes a module bottom plate and a module top plate arranged in parallel, which are integrally connected by a connecting plate, and the four corners of the module bottom plate are provided with leveling feet.

[0010] As a further improvement of this utility model, the control unit executes a signal fusion algorithm in the range transition interval so that the output weight W satisfies W = α×W1 + (1-α)×W2, where W1 and W2 are the outputs of the first weighing unit and the second weighing unit, respectively, and α is automatically adjusted according to the real-time load.

[0011] As a further improvement of this utility model, the control unit has zero-point drift and temperature drift compensation functions, and can perform self-learning optimization of threshold and fusion coefficient based on historical data.

[0012] As a further improvement of this utility model, when the force on the first weighing unit exceeds the threshold or the position is not in place, the control unit triggers the protection logic, drives the actuator to separate the container tray from the first weighing unit and lock the current mode.

[0013] The technical advantages of this utility model are as follows: the utility model has a reasonable and ingenious structure, with integrated structure and coaxial arrangement, small size and high rigidity, which is conducive to equipment integration; intelligent execution and position closed-loop control ensure accurate and repeated switching; in heavy weight mode, the first weighing unit is completely unloaded, which provides strong protection and avoids overload damage; the signal is independently acquired and can be fused and compensated in the transition zone to ensure continuous and stable data across the entire range; it has automatic zero-point / drift correction and threshold self-learning capabilities to ensure long-term stability and consistency. Attached Figure Description

[0014] Figure 1 This is a three-dimensional structural schematic diagram of the present invention.

[0015] Figure 2 This is a schematic diagram of the main structure of this utility model. Detailed Implementation

[0016] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings.

[0017] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. The described embodiments are merely some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0018] Figure 1 , 2 The system includes a second weighing unit 1, a first weighing unit 2, a first weighing support 2-1, an electromagnetic force connecting plate 3, a container tray 4, an execution bracket 5, a lifting plate 6, a lower container lifting frame 7, an upper container lifting frame 8, a weighing module base 9, a module base plate 9-1, a module base top plate 9-2, a connecting plate 9-3, a leveling foot 10, a first hexagon socket head cap screw 11, a second hexagon socket head cap screw 12, a connecting screw 13, an execution mechanism 14, a lifting support assembly 15, a control unit 16, a position sensor 17, etc.

[0019] like Figure 1 , 2 As shown, this utility model is a wide-range precision composite weighing sensor, characterized in that: it includes a weighing module base 9 and a second weighing unit 1 installed on the weighing module base 9, and the first weighing unit 2 and the second weighing unit 1 are arranged coaxially in the vertical direction to form a series force path.

[0020] The output end of the actuator 14 is connected to the lifting support assembly 15 to drive the container pallet 4 to rise and fall, so as to achieve contact or separation between the container pallet 4 and the first weighing unit 2; the container pallet 4 is used to carry the material to be weighed.

[0021] The control unit 16 automatically determines the metering mode based on the target weight, outputs a control signal to drive the actuator 14 to operate, and only collects the weighing unit signal corresponding to the current mode for weighing calculation.

[0022] It is understandable that, in practice, the actuator 14 can be any one of an electric actuator, a servo linear actuator, a pneumatic actuator, or a hydraulic actuator. The output end of the actuator 14 is connected to the lifting support assembly 15 to drive the container pallet 4 to rise or fall, thereby achieving contact or separation from the first weighing unit 2.

[0023] A position sensor 17 is installed at the output end of the actuator 14 to detect the lifting position in real time. The position sensor 17 can be a limit switch, photoelectric encoder, displacement sensor or force / pressure contact type position detector to realize closed-loop feedback and precise control of the lifting position.

[0024] The lifting support assembly 15 includes a lower container support frame 7 and an upper container support frame 8, which are positioned at intervals by several connecting screws 13 and sleeves to ensure a smooth lifting process without deflection.

[0025] The weighing module base 9 is an integral support structure, including a parallel module base plate 9-1 and a module top plate 9-2, which are integrally connected by a connecting plate 9-3 to form a rigid frame. The four corners of the module base plate 9-1 are equipped with leveling feet 10 for horizontal adjustment during installation to ensure that the sensor is subjected to uniform force.

[0026] The control unit 16 executes a signal fusion algorithm in the range transition interval so that the output weight W satisfies W = α×W1+ (1-α)×W2, where W1 and W2 are the outputs of the first weighing unit and the second weighing unit, respectively, and α is a fusion coefficient that is automatically adjusted according to the real-time load, with a value range of [0,1], so as to achieve smooth transition and continuous measurement between the two ranges.

[0027] The control unit 16 has zero-point drift and temperature drift compensation functions, and can perform self-learning optimization of threshold and fusion coefficient based on historical data. The control unit 16 has a built-in signal acquisition module, execution control module, and data processing module. The signals from the two weighing units are respectively connected to independent A / D conversion channels, and are sent to the data processing module after filtering and calibration.

[0028] The control unit 16 has zero-point drift and temperature drift compensation functions, and can perform self-learning optimization of range threshold and fusion coefficient based on historical data to improve long-term stability.

[0029] When the position sensor 17 detects that the lifting is not in place, or when the first weighing unit 2 outputs a warning that the force exceeds the threshold, the control unit 16 immediately triggers the protection logic, drives the actuator 14 to lift the container tray 4 to a safe position, locks the current mode and records the alarm information, effectively preventing the small-range unit from being damaged due to overload.

[0030] When the first weighing unit 2 is detected to be subjected to excessive force or not in the correct position, the control unit 16 triggers the protection logic, drives the actuator 14 to separate the container tray 4 from the first weighing unit 2 and locks the current mode.

[0031] like Figure 1 , 2 As shown, the second weighing sensor 2 in this utility model is installed above the first weighing sensor 1, and the two are arranged coaxially. The container tray 4 can selectively contact the two sensors through a lifting mechanism.

[0032] The lifting stroke of the container pallet 4 is driven by the lifting mechanism, enabling the container pallet 4 to contact or separate from the second weighing sensor 2.

[0033] The signals from the two load cells are connected to independent acquisition channels and then sent to the control system after A / D conversion and software calibration.

[0034] This utility model also provides a control method for a wide-range precision composite weighing sensor, including: S1. Determine whether to use the small range or large range mode by comparing the target formula value or real-time estimated weight with the range threshold. S2, output control signal to drive actuator 15 to act, so that container tray 4 contacts or separates from first weighing unit (2); S3. Closed-loop correction based on feedback from position sensor 17; S4. Perform signal fusion calculations in the transition interval; S5. Perform zero-point / drift compensation periodically; S6. Automatically switches to safe mode when overload or incomplete protection is triggered.

[0035] like Figure 1 , 2 As shown, the working principle of this utility model is as follows: (1) Small-range measurement mode: The control unit 16 determines that the current target value is in the small-range range (e.g., not higher than 80% of the full range of the first weighing unit) and sends a downward command to the actuator 14; the lifting support assembly 15 moves down, so that the container tray 4 contacts the first weighing unit 2, and the two weighing units form a series force path. The control unit only uses the signal of the first weighing unit 2 to participate in the calculation to achieve high-sensitivity measurement.

[0036] 1. Position of container tray 4: The container tray is located at the bottom and is in contact with the loading head of the second weighing sensor 2 (small range); at the same time, the first weighing sensor 1 (large range) is located below it and also participates in the force.

[0037] 2. Stress state: The actual load is transmitted through container tray 4 → second weighing sensor 2 (small range) → first weighing sensor 1 (large range) → weighing module base 9; because the two sensors are connected in series and subjected to force, the large range sensor bears the same load, but its signal is not collected and used in this mode.

[0038] 3. Signal acquisition: The system only acquires the signal from the second weighing sensor 2 (small range); the second weighing sensor 2 has higher sensitivity and resolution, which can realize high-precision small weight measurement.

[0039] 4. Advantages: Simple structure, no need for additional shunt mechanism; small range signal fully reflects subtle changes, meeting the requirements of high-precision weighing.

[0040] (2) Large range measurement mode: When the target value exceeds the set threshold, the control unit sends an upward command to the actuator; the lifting support assembly moves upward, the container tray 4 and the first weighing unit 2 form a mechanical gap, and the first weighing unit 2 is completely unloaded; the system only uses the signal of the second weighing unit 1 for measurement to adapt to large load measurement.

[0041] Control Logic and Algorithm: The control unit 16 integrates a signal acquisition module, an execution control module, and a data processing module. Signals from the two weighing units are input to independent A / D channels, filtered, calibrated, and then sent to the data processing module. During the transition range of range switching, the system performs linear weight fusion: W = α×W1 + (1-α)×W2, where W1 is the output of the first weighing unit, W2 is the output of the second weighing unit, and α is adaptively adjusted within the range [0,1] according to the real-time load. The system periodically performs zero-point drift detection and temperature compensation, and performs self-learning optimization of the threshold and fusion coefficient based on historical data.

[0042] Protection mechanism: When the position sensor 17 detects that the position is not in place or the first weighing unit 2 outputs a prompt that the force exceeds the threshold, the control unit 16 immediately issues a protection command, drives the actuator 14 to lift the container tray 4 to a safe position, locks the current mode and gives an alarm record, thereby preventing the small-range unit from being damaged by overload.

[0043] 1. Position of container pallet 4: Before measurement, the system determines the target weight as "heavy weight mode" and drives the lifting mechanism to lift the container pallet 4, so that the container pallet 4 is separated from the loading head of the second weighing sensor 2 (small range) to form a mechanical gap.

[0044] 2. Stress state: The second weighing sensor 2 (small range) is completely detached and no longer bears any load; the entire weight of the container pallet 4 is borne by the first weighing sensor 1 and transferred to the weighing module base 9.

[0045] 3. Signal Acquisition: The system switches the acquisition channel to acquire only the signal from the large-range weighing sensor; the large-range sensor has a robust structure, good linearity, and is suitable for heavy weight measurement.

[0046] 4. Advantages: Thorough mechanical isolation prevents overload in small ranges; maintains good stability and safety in the full-load area over large ranges.

[0047] III. Switching and Control Principles 1. Judgment basis: The system determines whether the weighing task falls within the "small range" or "large range" range based on the set target measurement value or formula parameters. If the target value is less than or equal to the set threshold (e.g., 0.8 × small range full scale), the system selects the small range mode; if the target value is greater than the set threshold, the system selects the large range mode.

[0048] 2. Switching process: The control system (configured in this utility model, which can be implemented by PLC or embedded control board, and the signal acquisition adopts an independent channel and is calibrated by software) outputs switching commands to drive the lifting mechanism; After the position sensor (used to detect the travel position of the lifting mechanism) confirms the arrival signal, it locks the current working mode; the switching is only performed before the weighing starts, and the sensor state is not changed during the weighing process.

[0049] 3. Signal Acquisition Logic: Both sensors are connected to the signal acquisition module, but the control system only enables the channel corresponding to the current mode to participate in the calculation; the other channel remains idle or in a monitoring state and does not participate in the weighing calculation. The switching action is ensured by the control logic to be completed before weighing begins, and the signal channel remains stable during the weighing process.

[0050] IV. Operational characteristics and advantages: 1. Mechanical series connection + selective force-bearing structure Small range allows for high-precision measurement of light weights, while large range allows for independent load-bearing of heavy weights.

[0051] 2. Automatic switching but not switching during metering. The switching action only occurs before the measurement begins, avoiding errors and vibrations caused by mechanical actions or signal switching during the measurement process.

[0052] 3. Wide measuring range and high precision integrated By combining two sensors with different ranges, continuous coverage from light weight to heavy weight can be achieved.

[0053] 4. Protective design In heavy weight mode, the second weighing sensor 2 (small range) is completely unloaded to avoid overload damage; in light weight mode, the first weighing sensor 1 bears the load simultaneously without affecting accuracy.

[0054] V. Summary of Principles: The second weighing sensor 2 is installed above the large range sensor, and the force path of the pallet is switched through the lifting mechanism.

[0055] When measuring small weights, the two sensors are connected in series and subjected to force, but only a small range signal is collected; when measuring large weights, the container tray 4 is lifted and separated from the second weighing sensor 2, the small range is not subjected to force, and only the large range participates in the measurement.

[0056] The system automatically determines which sensor to use before weighing begins based on the set measurement value, and maintains single-channel measurement without switching during the weighing process.

[0057] Finally, it should be noted that the above specific embodiments are only used to illustrate the technical solution of this utility model and not to limit it. Although this utility model has been described in detail with reference to examples, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solution of this utility model without departing from the spirit and scope of the technical solution of this utility model, and all such modifications and substitutions should be covered within the scope of the claims of this utility model.

Claims

1. A wide-range precision composite weighing sensor, characterized in that: It includes a weighing module base (9) and a second weighing unit (1) installed on the weighing module base (9). The first weighing unit (2) and the second weighing unit (1) are arranged coaxially in the vertical direction. The output end of the actuator (14) is connected to the lifting support assembly (15) to drive the container pallet (4) to lift and lower, so as to achieve contact or separation between the container pallet (4) and the first weighing unit (2); The control unit (16) automatically determines the metering mode based on the target weight, outputs a control signal to drive the actuator (14) to operate, and only collects the weighing unit signal corresponding to the current mode for weighing calculation.

2. The wide-range precision composite weighing sensor as described in claim 1, characterized in that: The actuator (14) is any one of an electric actuator, a servo linear actuator, a pneumatic actuator, or a hydraulic actuator.

3. The wide-range precision composite weighing sensor as described in claim 1, characterized in that: The output end of the actuator (14) is equipped with a position sensor (17), which can be a limit switch, photoelectric encoder, displacement sensor or force / pressure contact type position detector.

4. The wide-range precision composite weighing sensor as described in claim 3, characterized in that: The lifting support assembly (15) includes a lower container support frame (7) and an upper container support frame (8), which are positioned at intervals by a number of connecting screws (13) and sleeves.

5. The wide-range precision composite weighing sensor as described in claim 1, characterized in that: The weighing module base (9) includes a module base plate (9-1) and a module top plate (9-2) arranged in parallel. The two are connected as a whole by a connecting plate (9-3), and the four corners of the module base plate (9-1) are provided with leveling feet (10).

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