Mine truck cab air filtration and positive pressure control system and control method thereof
By using multi-stage filtration and closed-loop PID positive pressure control, the sealing and filtration problems of the cab of the mining dump truck have been solved, achieving efficient removal of DPM and dust, and ensuring that the driver works in a stable positive pressure environment.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-05
- Publication Date
- 2026-03-27
AI Technical Summary
Mining dump truck cabs suffer from poor sealing, infiltration of polluted air, a single filtration system that cannot effectively intercept submicron particles, and a lack of positive pressure maintenance measures, resulting in drivers being exposed to high concentrations of diesel particulate matter and dust.
It adopts a multi-stage filtration system, including an external pre-filtration module, a main processing unit, a positive pressure maintenance module, and a recirculation purification module. Combined with a PID controller and an anti-misoperation interlock module, it forms a stable positive pressure environment and performs efficient filtration of incoming and circulating air.
It creates a stable positive pressure of ≥50 Pa in the cab, removes more than 99% of DPM, ensures that the driver's exposure concentration is below 160 μg/m³, and provides a clean, constant temperature air environment, suitable for mobile equipment such as open-pit mines.
Smart Images
Figure CN121734052A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the technical field of air treatment of a mine truck cab, and particularly relates to a mine truck cab air filtration and positive pressure control system and a control method thereof. BACKGROUND
[0002] The mine dump truck is widely used in major engineering projects such as mines, water conservancy, ports and wharfs, and is used for transporting ores or earthwork to target locations, and has the characteristics of large load, flexible maneuvering, high work efficiency and the like. The mine dump truck belongs to a non-road dump truck, and its working environment is complex and harsh, and there are many uncertain dangerous factors, which puts forward higher requirements on the comprehensive performance of the whole machine. The cab is a key component of the mine dump truck, and the advantages and disadvantages of its performance are directly related to the most intuitive and deepest impression of the customer on the whole machine. Therefore, safety, reliability, aesthetics, convenience and comfort should be fully considered in the design process of the cab of the mine dump truck, so as to provide a safe and comfortable working environment for the operator, improve the work efficiency, and have wide social and economic benefits.
[0003] The working environment of the mine truck is harsh, and the mine truck driver is exposed to a high-concentration diesel particulate matter (DPM) and inhalable dust environment for a long time. The existing cab mainly has the following defects: it simply depends on a personal respirator and cannot solve the problem of whole body exposure; the conventional cab has poor sealing performance, and the external polluted air continuously penetrates; the filtration system is single, and the DPM submicron particles are not efficiently intercepted; the cab has no continuous positive pressure maintenance measures, and the door and window are invalid for an instant; and the recirculated air is not filtered, resulting in secondary dust raising in the cab.
[0004] Therefore, an engineering control scheme integrating "multi-stage filtration-positive pressure maintenance-recirculation purification-air conditioning temperature regulation" is urgently needed to systematically reduce the exposure concentration of the operator to DPM. SUMMARY
[0005] The purpose of the present application is to provide a mine truck cab air filtration and positive pressure control system and a control method thereof, which forms a stable positive pressure of ≥50 Pa in the cab, removes ≥99 % of DPM from the entering and circulating air, and ensures that the exposure concentration of the driver is lower than 160 μg / m³TC.
[0006] To achieve the above purpose, the technical solution used by the present application is as follows: The mine truck cab air filtration and positive pressure control system comprises: An external pre-filtering module is installed at the external air inlet of the cab, and is used for pre-treating the air entering the cab and removing dust with a particle size of >10 μm; A main processing unit is installed at an internal air outlet of the cab to send the pre-processed air into the cab, remove solid particles with a particle size of >0.3 μm in the air, and adjust the air intake; A positive pressure maintaining module is configured to measure the air pressure in the cab, adjust the rotating speed of the variable frequency fan according to the pressure difference between the inside and outside of the cab, and keep the pressure difference between the inside and outside of the cab at 50-150 Pa.
[0007] Further, the main processing unit comprises a variable frequency fan, an evaporator / condenser, and a main filter; the variable frequency fan adjusts the air supply by changing the rotating speed, the evaporator / condenser is configured to adjust the air temperature entering the cab, and the main filter is configured to remove solid particles with a particle size of >0.3 μm.
[0008] Further, the positive pressure maintaining module comprises a pressure difference sensor and a PID controller of the variable frequency fan; the PID controller adjusts the rotating speed of the fan in real time, compares the pressure difference between the inside and outside of the cab, and adjusts the rotating speed of the variable frequency fan according to the pressure difference between the inside and outside of the cab; and the pressure difference sensor is configured to measure the air pressure in the cab and send the pressure value to the PID controller.
[0009] Further, the method further comprises a recirculation purification module; the recirculation purification module is installed below the floor of the cab, has an inlet on the floor of the cab, and has an outlet connected to the internal air outlet of the cab through a pipeline; the recirculation purification module is configured to filter the entering air, and the filtered air enters the air inlet of the main processing unit.
[0010] Further, the recirculation purification module is internally provided with a recirculation filter; the recirculation filter is configured to suck in air by the positive pressure of the cab and return the filtered air to the main processing unit.
[0011] Further, the method further comprises an anti-misoperation interlocking module; the anti-misoperation interlocking module comprises a K1 relay; the normally open contact of the K1 relay is connected to the power supply circuit of the variable frequency fan through a wire.
[0012] Further, the pressure difference sensor has a range of 0-500 Pa and an output of 4-20 mA.
[0013] The method for filtering and controlling the positive pressure of a cab of a mine vehicle comprises the following steps: An external pre-filtering module is configured to pre-process the air entering the cab and remove dust with a particle size of >10 μm; A main processing unit is configured to send the pre-processed air into the cab, remove solid particles with a particle size of >0.3 μm in the air, and adjust the air intake; A positive pressure maintaining module is configured to measure the air pressure in the cab, adjust the rotating speed of the variable frequency fan according to the pressure difference between the inside and outside of the cab, and keep the pressure difference between the inside and outside of the cab at 50-150 Pa.
[0014] Preferably, the recirculation purification module filters the air entering the cab, and the filtered air enters the air inlet of the main processing unit.
[0015] Preferably, the variable frequency fan adjusts the air volume by changing the speed. When the door or window is opened, causing the pressure difference to drop by more than 20%, the variable frequency fan automatically increases its speed to 120% of the maximum speed within 5 seconds and returns to a steady state 30 seconds after the door is closed. After the engine is turned off, the variable frequency fan runs for 60 seconds to remove residual pollutants from the room.
[0016] The technical effects of this invention include: This invention reduces the DPM exposure concentration in the driver's cab by more than 99% through multi-stage filtration and closed-loop PID positive pressure control. It can be widely used in mobile equipment such as open-pit mines to provide drivers with a clean, constant-temperature, and positive-pressure air environment.
[0017] This invention creates a stable positive pressure of ≥50 Pa in the driver's cab and removes ≥99% of DPM from the incoming and recirculated air, ensuring that the driver's exposure concentration is below 160 μg / m³ TC (Mine Safety and Health Administration (MSHA) final limit).
[0018] 1. Systematic engineering control, driver's cab exposure reduction factor (ERF) > 100; 2. The positive pressure in the cab is not affected by door opening and returns to the set value within 30 seconds; 3. The recirculation filter ensures that the background PM2.5 concentration in the driver's cab is <10 μg / m³; 4. Modular design allows for non-destructive retrofitting of new / old equipment. Attached Figure Description
[0019] Figure 1 This is a schematic diagram of the working principle of the air filtration and positive pressure control system for the mining truck cab in this invention; Figure 2 This is the circuit diagram of the anti-misoperation interlocking module in this invention. Detailed Implementation
[0020] The following description fully illustrates specific embodiments of the present invention to enable those skilled in the art to practice and reproduce it. To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.
[0021] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.
[0022] like Figure 1 The diagram shown is a schematic diagram of the working principle of the air filtration and positive pressure control system for the mining truck cab in this invention.
[0023] This invention is applicable to high dust and high diesel particulate matter (DPM) environments in open-pit mines, providing drivers with a clean, constant-temperature, positive-pressure air environment.
[0024] The air filtration and positive pressure control system for the mining truck cab includes: The external pre-filter module 10 is installed at the external air inlet of the cab to pre-treat the air entering the cab and remove dust particles with a particle size >10μm. The external pre-filtration module 10 uses a MERV8-11 pleated filter element, which can remove dust particles larger than 10μm.
[0025] The main processing unit 20 is installed at the internal air outlet of the cab. It is used to send pre-treated air into the cab to remove solid particles with a particle size >0.3μm from the air and to regulate the air intake volume. The main processing unit 20 includes: a variable frequency fan 21, an evaporator / condenser 22, and a main filter 23; the variable frequency fan 21 adjusts the air volume by changing the speed, the maximum air volume of the variable frequency fan 21 is 600 m³ / h, and the steady-state power consumption is 280W; the evaporator / condenser 22 is used to regulate the air temperature entering the cab, and maintains the air temperature at the set temperature through heat exchange.
[0026] The main filter 23 is a replaceable MERV16 grade filter that removes solid particles with a particle size >0.3μm, with a removal efficiency of ≥99.97% for 0.3μm solid particles and a dust holding capacity >200g.
[0027] The positive pressure maintenance module 30 is used to measure the air pressure inside the cab and adjust the speed of the variable frequency fan 21 according to the pressure difference between the inside and outside of the cab to maintain the pressure difference between the inside and outside of the cab at 50-150Pa.
[0028] The positive pressure maintenance module 30 includes: a differential pressure sensor 31 and a PID (proportional-integral-derivative) controller for the variable frequency fan. The PID controller adjusts the fan speed in real time. The differential pressure sensor 31 is used to measure the air pressure inside the cab and send the pressure value to the PID controller. The PID controller compares the pressure difference between the inside and outside of the cab and adjusts the speed of the variable frequency fan 21 according to the pressure difference between the inside and outside of the cab.
[0029] The differential pressure sensor 31 has a range of 0-500 Pa and an output of 4-20 mA.
[0030] The recirculation and purification module 40 is located in the cab and installed below the cab floor. Its inlet is located on the cab floor, and its outlet is connected to the cab’s internal air outlet through a pipe. It is used to filter the incoming air, and the filtered air enters the air inlet of the main processing unit 20.
[0031] The recirculation purification module 40 is equipped with a recirculation filter 41. It uses the positive pressure of the cab to draw in air. The air containing dust is drawn in and filtered by the recirculation filter 41 with an efficiency of ≥85% before being returned to the main processing unit 20, thereby reducing dust.
[0032] The recirculation filter 41 is MERV13 with a recirculation ratio of 80%.
[0033] In this preferred embodiment, an anti-misoperation interlocking module is also included. Its filter / pressurization circuit is interlocked to the engine ignition signal via a wire. The operator can only adjust the fan speed and cannot turn off the purification function, thus ensuring positive pressure in the cab.
[0034] like Figure 2 The diagram shown is a circuit schematic of the anti-misoperation interlocking module in this invention.
[0035] The anti-misoperation interlock module includes: a K1 relay and a filter / pressurization circuit. The normally open contact of the K1 relay is connected to the power supply circuit of the variable frequency fan 21 via a wire. The filter / pressurization circuit is interlocked to the engine ignition signal via a wire. The anti-misoperation interlock module 50 is hardwired to the vehicle ignition signal, ensuring that the filter / pressurization circuit cannot be shut off during engine operation.
[0036] The normally open contact of relay K1 is connected to the ECU (electronic control unit) of variable frequency fan 21 via a wire. The ECU only outputs a PWM speed control signal and cannot cut off the power supply to relay K1, thus preventing the purification function from being turned off.
[0037] PWM speed control signals control motor speed by adjusting the duty cycle of the pulse width modulation (PWM) signal.
[0038] The method for air filtration and positive pressure control in the cab of a mining truck includes the following steps: Step 1: The external pre-filter module 10 pre-treats the air entering the cab to remove dust particles with a size >10μm; Step 2: The main processing unit 20 sends the pre-treated air into the cab to remove solid particles with a particle size >0.3μm from the air and adjusts the air intake volume; The variable frequency fan 21 adjusts the air volume by changing the speed. After the vehicle is started, the variable frequency fan runs at the highest speed for 30 seconds to quickly establish positive pressure. The evaporator / condenser 22 regulates the air temperature entering the cab and maintains the air temperature at the set temperature through heat exchange.
[0039] Step 3: The positive pressure maintenance module 30 measures the air pressure inside the cab and adjusts the speed of the variable frequency fan 21 according to the pressure difference between the inside and outside of the cab to maintain the pressure difference between the inside and outside of the cab at 50-150Pa.
[0040] The PID (proportional-integral-derivative) controller of the variable frequency fan adjusts the fan speed in real time. The differential pressure sensor 31 measures the air pressure in the cab and sends the pressure value to the PID controller. The PID controller compares the pressure difference between the inside and outside of the cab and adjusts the speed of the variable frequency fan 21 according to the pressure difference.
[0041] When a door or window is opened, causing a pressure drop of >20%, the variable frequency fan 21 automatically accelerates to 120% of its maximum speed within 5 seconds and returns to steady state 30 seconds after the door is closed. After the engine is turned off, the variable frequency fan 21 runs for a delay of 60 seconds to remove residual pollutants from the room.
[0042] Step 4: The recirculation and purification module 40 filters the air entering the cab, and the filtered air enters the air inlet of the main processing unit 20.
[0043] The terminology used in this invention is descriptive and exemplary, not restrictive. Since this invention can be embodied in many forms without departing from the spirit or essence of the technical solution, it should be understood that the above embodiments are not limited to any of the foregoing details, but should be interpreted broadly within the spirit and scope defined by the appended claims. Therefore, all variations and modifications falling within the scope of the claims or their equivalents should be covered by the appended claims.
Claims
1. A mining truck cab air filtration and positive pressure control system, characterized in that, include: An external pre-filter module is installed at the external air inlet of the cab to pre-treat the air entering the cab and remove dust particles with a size greater than 10μm. The main processing unit is installed at the air outlet inside the cab. It is used to send pre-treated air into the cab, remove solid particles with a particle size >0.3μm from the air, and regulate the air intake volume. The positive pressure maintenance module is used to measure the air pressure inside the cab and adjust the speed of the variable frequency fan according to the pressure difference between the inside and outside of the cab to maintain the pressure difference between the inside and outside of the cab at 50-150Pa.
2. The air filtration and positive pressure control system for the mining truck cab as described in claim 1, characterized in that, The main processing unit includes: a variable frequency fan, an evaporator / condenser, and a main filter; the variable frequency fan adjusts the air volume by changing the speed, the evaporator / condenser is used to regulate the temperature of the air entering the cab, and the main filter is used to remove solid particles with a particle size >0.3μm.
3. The air filtration and positive pressure control system for the mining truck cab as described in claim 1, characterized in that, The positive pressure maintenance module includes: a differential pressure sensor and a PID controller for the variable frequency fan; the PID controller adjusts the fan speed in real time, compares the pressure difference between the inside and outside of the cab, and adjusts the speed of the variable frequency fan according to the pressure difference between the inside and outside of the cab; the differential pressure sensor is used to measure the air pressure inside the cab and send the pressure value to the PID controller.
4. The air filtration and positive pressure control system for the mining truck cab as described in claim 1, characterized in that, Also includes: The recirculation and purification module is installed under the floor of the cab. Its inlet is located on the floor of the cab, and its outlet is connected to the internal air outlet of the cab through a pipe. It is used to filter the incoming air, and the filtered air enters the air inlet of the main processing unit.
5. The air filtration and positive pressure control system for the mining truck cab as described in claim 4, characterized in that, The recirculation purification module is equipped with a recirculation filter. It uses the positive pressure in the cab to draw in air, which is then filtered and returned to the main processing unit.
6. The air filtration and positive pressure control system for the mining truck cab as described in claim 1, characterized in that, Also includes: The anti-misoperation interlocking module includes: a K1 relay and a filter / pressurization circuit. The normally open contact of the K1 relay is connected to the power supply circuit of the variable frequency fan through a wire, and the filter / pressurization circuit is interlocked to the engine ignition signal through a wire.
7. The air filtration and positive pressure control system for the mining truck cab as described in claim 3, characterized in that, The differential pressure sensor has a range of 0-500Pa and an output of 4-20mA.
8. The method for controlling air filtration and positive pressure in the cab of a mining truck as described in any one of claims 1-7, characterized in that, include: The external pre-filter module pre-treats the air entering the cab to remove dust particles larger than 10μm. The main processing unit sends the pre-treated air into the cab to remove solid particles with a particle size >0.3μm and adjust the air intake volume; The positive pressure maintenance module measures the air pressure inside the cab and adjusts the speed of the variable frequency fan according to the pressure difference between the inside and outside of the cab to maintain the pressure difference between the inside and outside of the cab at 50-150Pa.
9. The method for air filtration and positive pressure control in the cab of a mining truck as described in claim 8, characterized in that, The recirculation and purification module filters the air entering the cab, and the filtered air enters the air inlet of the main processing unit.
10. The method for air filtration and positive pressure control in the cab of a mining truck as described in claim 8, characterized in that, The variable frequency fan adjusts the air volume by changing the speed. When the pressure difference drops by more than 20% due to the opening of the car door or window, the variable frequency fan will automatically increase its speed to 120% of the maximum speed within 5 seconds and return to a steady state 30 seconds after the door is closed. After the engine is turned off, the variable frequency fan will run for 60 seconds to remove residual pollutants from the room.