A semi-trailer dumper safety lifting hydraulic system

Abstract

The utility model provides a kind of semi-trailer dumper safety lifting hydraulic system, including hydraulic oil tank, gear pump by oil circuit in turn series connection, pneumatic control reversing valve connected in control hand valve by gas circuit, and lifting cylinder, still include dynamic inclination sensor, controller and pneumatic electromagnetic valve;In control gas circuit, pneumatic electromagnetic valve is connected in series, and it is controlled based on dynamic inclination sensor data controller, to build an active safety closed loop directly acting on lifting control source.The scheme fundamentally subverts prior art only alarm without intervention or passive protection mode needing to cut off the power of whole vehicle, realizes millisecond level forced stop to dangerous lifting action without interrupting the power of main vehicle.This effectively solves the major safety hazard that semi-trailer dumper is prone to rollover when lifting operation on rough road.

Description

Technical Field

[0001] This utility model relates to the field of hydraulic control technology, specifically to a safe lifting hydraulic system for a semi-trailer dump truck. Background Technology

[0002] While existing technologies offer various solutions aimed at improving the safety of dump truck operations, their design concepts and effectiveness have significant limitations. For example, patent CN120056847A discloses a technology that uses a lifting angle sensor to control the unloading mode, but this sensor is only used to trigger phase transitions in the lifting process and cannot assess or intervene in the dynamic risk of rollover during lifting; it is a functional application rather than a safety design. Patent CN119435524A focuses on calculating load capacity through slope sensing; its technology is essentially static parameter calculation rather than real-time safety control. A closer safety solution, such as CN223137587U, uses photoelectric sensors and an emergency stop system, but its application scenario is hydraulic press protection, stopping the machine by cutting off the power. This crude intervention method of completely shutting down the entire system is completely unsuitable for dump truck operations that require maintaining power for lifting. Therefore, existing technologies lack an effective means to provide real-time active safety protection for the lifting action itself without interrupting vehicle power.

[0003] Further analysis reveals that the root cause of the shortcomings of existing technologies lies in their failure to break down system barriers and achieve closed-loop safety linkage across systems. Whether it's the mode control in CN120056847A or the overload protection implemented through a hydraulic servo valve in CN120332295A, their intervention logic is limited to a single hydraulic or electrical circuit. For the semi-trailer dump truck lifting system controlled by the critical component of the "pneumatic directional valve," the above solutions cannot intervene in the core link of its control air circuit, thus failing to stop the dangerous lifting action at its source. Furthermore, while CN120135954A mentions using a CAN bus for information display, its function is limited to status feedback, failing to convert perceived information into control commands that can drive actuators, creating an information silo of "perception without execution." Therefore, a long-standing unresolved technical challenge in this field remains: how to create an active safety system that can directly act on the lifting control air circuit, respond rapidly, and not affect the power of the main vehicle, in order to fundamentally prevent rollover accidents. Utility Model Content

[0004] This utility model proposes a safe lifting hydraulic system for semi-trailer dump trucks, which solves the problem that existing lifting systems cannot judge and intervene in the dynamic rollover risk during the lifting process.

[0005] The technical solution of this utility model is implemented as follows: A hydraulic lifting system for a semi-trailer dump truck includes a hydraulic oil tank, a gear pump, a pneumatically controlled directional valve, and a lifting cylinder, connected in series by an oil circuit. The pneumatically controlled directional valve is connected to a control hand valve via an air circuit. The system also includes a dynamic tilt sensor, a controller, and a pneumatic solenoid valve. The dynamic tilt sensor is fixedly installed at the bottom of the dump truck's cargo box. The pneumatic solenoid valve is connected in series in the air circuit between the control hand valve and the pneumatically controlled directional valve via a three-way connector. The signal input terminal of the controller is connected to the signal output terminal of the dynamic tilt sensor via a wiring harness, and the switch signal output terminal of the controller is connected to the solenoid coil drive terminal of the pneumatic solenoid valve via a wiring harness.

[0006] Furthermore, the controller is connected to a display screen installed in the driver's cab via a CAN bus harness.

[0007] Furthermore, the display screen's interface includes a numerical display area and a three-dimensional dynamic graphic area.

[0008] Furthermore, it also includes a limit valve, which is connected in the air line between the control hand valve and the pneumatic solenoid valve.

[0009] Furthermore, the pneumatic solenoid valve is a normally closed two-position three-way valve.

[0010] Furthermore, the controller is an embedded microcontroller, and the time interval from when the received roll angle data exceeds the safety threshold to when the switch signal output terminal outputs a control signal is no more than 200 milliseconds.

[0011] Furthermore, the dynamic tilt sensor is a dual-axis sensor capable of simultaneously detecting roll and pitch angles.

[0012] The beneficial effects of the technical solution provided in this application are as follows: 1. This semi-trailer dump truck's safety lifting hydraulic system incorporates a pneumatic solenoid valve connected in series in the control air circuit, which is then controlled by a controller based on dynamic tilt angle sensor data. This creates an active safety closed loop that directly affects the lifting control source. This solution fundamentally overturns the passive protection mode of existing technologies that only issue alarms without intervention or require cutting off the vehicle's power. It achieves millisecond-level forced cessation of dangerous lifting actions without interrupting the main vehicle's power. This effectively solves the major safety hazard of semi-trailer dump trucks easily overturning during lifting operations on rough roads, transforming safety accidents from "post-accident remediation" to "pre-accident prevention," greatly improving operational safety. 2. This semi-trailer dump truck's safety lifting hydraulic system, by simply adding a pneumatic solenoid valve and sensor to the existing air circuit, requires no modifications to the complex hydraulic main circuit or vehicle power system, greatly reducing the difficulty and cost of modification. Simultaneously, it utilizes the "reset upon air loss" mechanical characteristic of the pneumatically controlled directional valve to achieve safety interruption, making the entire intervention process entirely dependent on the physical action of the hardware. This results in rapid response and extremely high reliability, avoiding safety risks that may be caused by software failures or electromagnetic interference, making it highly suitable for the harsh working environments of engineering vehicles. 3. The safety lifting hydraulic system of this semi-trailer dump truck transmits tilt angle data to the cab display screen in real time via the CAN bus, and intuitively displays the lifting posture and tilt status of the cargo box in the form of three-dimensional dynamic icons, providing the operator with unprecedented visual monitoring capabilities and realizing a technological leap from "human experience judgment" to "intelligent active protection". The use of a roll angle threshold range of 3° to 5° ensures the accuracy of safety intervention; the selection of a normally closed two-position three-way valve realizes the fail-safe mode, ensuring automatic cut-off of the air circuit in the event of power failure; the fast response time of no more than 200 milliseconds far exceeds the speed of human reaction, greatly improving the effectiveness of protection; and the monitoring of the pitch angle by dual-axis sensors expands the anti-rollover protection function, forming a complementary double protection with the mechanical limit valve. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 This is a schematic diagram of the traditional lifting hydraulic system of this utility model; Figure 2 This is a schematic diagram of the safety lifting hydraulic system of this utility model.

[0015] In the diagram: 1. Hydraulic oil tank, 2. Gear pump, 3. Pneumatic directional valve, 4. Lifting cylinder, 5. Control hand valve, 6. Dynamic tilt sensor, 7. Controller, 8. Pneumatic solenoid valve, 9. Display screen, 10. Limit valve. Detailed Implementation

[0016] The technical solution of this utility model will be clearly and completely described below with reference to its embodiments. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0017] like Figure 2 As shown, this utility model system inherits and integrates the main components of a traditional semi-trailer dump truck lifting system in terms of mechanical structure. The hydraulic oil tank 1, gear pump 2, pneumatic directional valve 3, and lifting cylinder 4 are connected in series via metal oil pipes in accordance with existing technology to form a hydraulic main circuit. The input shaft of the gear pump 2 is connected to the vehicle's gearbox via a power take-off (PTO) to obtain power. The pneumatic directional valve 3 is preferably a three-position four-way valve, with its neutral position function being either M-type or H-type, to ensure that when it is reset to the neutral position, the hydraulic cylinder 4 can be reliably locked, and the system achieves unloading.

[0018] Regarding the control air circuit, the main vehicle air source from the vehicle's air reservoir is connected to the original vehicle's control hand valve 5 via a pipeline. A key improvement of this invention lies in the addition of a pneumatic solenoid valve 8 connected in series via a three-way connector in the air circuit between the output port of the control hand valve 5 and the control port of the pneumatic directional valve 3. The selection of this pneumatic solenoid valve 8 is crucial as it is the core component for system intervention. In a preferred embodiment, the pneumatic solenoid valve 8 is a normally closed two-position three-way valve. Its inlet is connected to the output port of the control hand valve 5 via an air pipe, its outlet is connected to the control port of the pneumatic directional valve 3 via an air pipe, and its exhaust port is directly connected to the atmosphere via a muffler. In this configuration, when the solenoid valve is de-energized, the passage between its inlet and outlet is cut off, while the outlet and exhaust port are connected. This causes the control air pressure guided to the pneumatic directional valve 3 to be rapidly released to the atmosphere, thereby automatically resetting the pneumatic directional valve 3 to the neutral position under the action of its internal spring, forcibly stopping the lifting action. This is a typical "fail-safe" design, which ensures that the gas path is cut off and the system is in the safest state even if the system is completely powered off.

[0019] The sensing system consists of a dynamic tilt sensor 6. This sensor should be an industrial-grade product suitable for harsh vehicle environments. Its installation location is crucial for monitoring accuracy; it must be securely mounted on the main beam at the bottom of the dump truck's cargo box or other structural components that accurately reflect the overall posture of the cargo box to avoid measurement errors caused by factors such as chassis torsion. In a further optimized embodiment, the dynamic tilt sensor 6 is a dual-axis sensor capable of simultaneously detecting the cargo box's roll and pitch angles with high frequency and high precision.

[0020] The system's control center is a controller 7, which is essentially an embedded microcontroller. This controller 7 should be encapsulated within a housing with a protection rating of at least IP67 and installed in a location with low vibration and relatively good environmental conditions, such as the cab or chassis. Its electrical connections are as follows: the signal input terminal of the controller 7 is connected to the signal output terminal of the dynamic tilt sensor 6 via a shielded wiring harness to receive real-time attitude data; its switch signal output terminal (usually via a relay) is connected to the solenoid coil drive terminal of the pneumatic solenoid valve 8 via a wiring harness to control its on / off state; furthermore, its CAN communication port is connected to the CAN interface of the display screen 9 located in the cab via a CAN bus wiring harness.

[0021] The controller 7 has at least one preset safety threshold internally stored. This threshold is a critical anti-rollover angle determined based on extensive experiments and calculations. In a typical embodiment, the preset safety threshold for the roll angle is set to 3° to 5°. This range effectively intervenes before a hazard occurs, while avoiding false triggering due to slight road surface irregularities. The firmware of the controller 7 is configured to cyclically execute the following control logic: read the roll angle data sent by the dynamic tilt sensor 6 in real time; compare this data with the internally stored safety threshold; once it is determined that the current roll angle data exceeds the safety threshold, its control logic is immediately triggered, outputting a low-level (or high-level, depending on the drive circuit design) control signal from the switch signal output terminal to de-energize the solenoid coil of the pneumatic solenoid valve 8, thereby instantly cutting off the control air path. The response time of the entire process, from data exceeding the threshold to signal output, is optimized to no more than 200 milliseconds, which is much faster than human reaction speed, ensuring timely intervention.

[0022] For systems equipped with dual-axis sensors, a lifting height limit threshold can be pre-stored in the controller 7. Its control logic can be expanded to simultaneously monitor pitch angle data; when the cargo box lifting angle exceeds the limit threshold, a control signal is also output to cut off the air supply. This forms redundant protection with the mechanical limit valve 10, preventing over-lifting accidents after electronic system failure. It should be noted that the mechanical limit valve 10, as a traditional, independent safety device, can be retained in this system. It is connected in the air supply line between the control hand valve 5 and the pneumatic solenoid valve 8, and its function runs parallel to and does not interfere with this electronic safety system, together forming a multi-layered safety protection.

[0023] The human-machine interface is implemented by the display screen 9. This display screen 9 can be a TFT LCD screen of at least 4.3 inches, installed in a conveniently observable position within the driver's cab. Its software interface is designed to include a numerical display area and a three-dimensional dynamic graphic area. The numerical display area directly displays "lifting angle:" in digital form. ° and tilt value: The 3D dynamic graphic area includes a simplified icon of the dump truck's cargo box and a tilt status indicator icon. The cargo box icon rises and rotates synchronously on the screen based on the lifting angle data sent by controller 7, visually simulating the posture of a real cargo box. The tilt status indicator dynamically changes its color and coverage based on the roll angle value and direction, providing the operator with a clear visual warning of the risk level.

[0024] In summary, through the specific hardware selection, installation method, connection relationship and control logic described above, this utility model constructs a rapid-response, stable, reliable and intuitive active safety system, which effectively solves the core safety hazards in the lifting operation of semi-trailer dump trucks.

[0025] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A hydraulic safety lifting system for a semi-trailer dump truck, comprising a hydraulic oil tank (1), a gear pump (2), a pneumatically controlled directional valve (3), and a lifting cylinder (4) connected in series by an oil circuit, wherein the pneumatically controlled directional valve (3) is connected to a control hand valve (5) via an air circuit; characterized in that, It also includes a dynamic tilt sensor (6), a controller (7), and a pneumatic solenoid valve (8); the dynamic tilt sensor (6) is fixedly installed at the bottom of the dump truck's cargo box; the pneumatic solenoid valve (8) is connected in series in the air path between the control hand valve (5) and the pneumatic reversing valve (3) through a three-way connector; the signal input terminal of the controller (7) is connected to the signal output terminal of the dynamic tilt sensor (6) through a wiring harness, and the switch signal output terminal of the controller (7) is connected to the electromagnetic coil drive terminal of the pneumatic solenoid valve (8) through a wiring harness.

2. The safety lifting hydraulic system for semi-trailer dump trucks as described in claim 1, characterized in that, The controller (7) is connected to the display screen (9) installed in the driver's cab via a CAN bus harness.

3. The hydraulic system for safe lifting of a semi-trailer dump truck as described in claim 2, characterized in that, The display screen (9) includes a numerical display area and a three-dimensional dynamic graphic area.

4. The hydraulic system for safe lifting of a semi-trailer dump truck as described in claim 1, characterized in that, It also includes a limit valve (10), which is connected in the air path between the control hand valve (5) and the pneumatic solenoid valve (8).

5. The safety lifting hydraulic system for semi-trailer dump trucks as described in claim 1, characterized in that, The pneumatic solenoid valve (8) is a normally closed two-position three-way valve.

6. The hydraulic system for safe lifting of a semi-trailer dump truck according to claim 1, characterized in that: The controller (7) is an embedded microcontroller, and the time interval from when the received roll angle data exceeds the safety threshold to when the switch signal output terminal outputs a control signal is no more than 200 milliseconds.

7. The safety lifting hydraulic system for a semi-trailer dump truck according to claim 1, characterized in that: The dynamic tilt sensor (6) is a dual-axis sensor that can simultaneously detect roll angle and pitch angle.

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