Overview of the development of modern loader technology
1 Overall machine productivity improvement and fuel saving technology
1.1 High-performance engine technology
By improving Engine performance improves the productivity of the entire machine and reduces fuel consumption, which is the basis for improving the performance and quality of the entire machine.
(1) The so-called ACERT technology is applied to the engine. This is a technology that systematically optimizes fuel supply, air supply, combustion process and exhaust gas emissions through a new electronic control module. This technology reduces emissions and maintains longevity and reliability without compromising fuel economy and performance.
(2) Track and monitor the operating status of each engine subsystem. In addition to continuous monitoring of cooling temperature, intake air temperature, lubricating oil pressure, fuel pressure, engine speed and other indicators, the engine load condition can also be monitored. When the load is too high, the system will automatically reduce the engine output power to protect It is protected from destruction.
(3) High-performance electronically controlled fuel timing injection technology. Optimize the engine's low-speed and high-speed fuel combustion conditions to improve the fuel supply response speed to match the bucket digging force and hydraulic system response speed.
(4) Apply a high-torque engine to match it with a large-capacity hydraulic torque converter, thereby maximizing the working efficiency under low-speed conditions and reducing fuel consumption by 15%.
(5) Apply dual-mode engine power selection system. The engine has two working modes for the operator to choose at will, namely normal working mode and power working mode. The normal working mode is suitable for conventional loading operations to obtain maximum fuel efficiency; the power working mode is suitable for shoveling hard materials or steep slope climbing conditions to obtain maximum power output. The dual-mode power selection system allows operators to easily adjust engine performance to match operating requirements.
(6)Constant net power output control. Generally, the engine is under total power constant output control, that is, when accessories such as air conditioners or cooling fans are working, in order to ensure that the total power remains unchanged, the net power required for actual work will change accordingly. The new engine electronic control system can provide constant net power output under full-load operating conditions of the auxiliary device, thereby improving overall machine productivity and fuel efficiency.
(7) Separate constant temperature cooling system. The system can electronically adjust and control the fan speed as required, monitor the engine cooling temperature, intake manifold temperature, transmission oil temperature and hydraulic oil temperature, and use these data to control and maintain the fan speed at the system's normal operating temperature level.
Many existing loader cooling systems draw air in from the sides of the machine and exhaust it from the rear of the machine through the engine compartment. The new cooling system uses a non-metallic protective layer to isolate the cooling system from the engine compartment. A hydraulically driven variable speed fan draws clean air from the rear of the machine and exhausts it through the sides and engine hood. The result is optimal cooling efficiency, improved fuel efficiency, reduced radiator air lock and operating noise.
1.2 Gearbox transmission technology
(1) Automatic gearbox four-mode selection system. The transmission has one manual shift and three automatic shift modes (i.e. low, medium and high gear). Through reasonable selection, the operator can match the mechanical operating conditions with the best performance of the engine.
The manual shifting mode can fix the transmission ratio of the transmission system through the gear lever, so that the whole machine can obtain a constant operating speed. The low-speed automatic transmission mode ensures smooth gear shifting when the engine is running at low speed, is suitable for general shoveling operations, and has lower fuel consumption. The medium-speed automatic transmission mode is suitable for gear shifting and faster work requirements under medium-speed engine operating conditions. The high-speed automatic shifting mode is the shifting condition of the engine at high speed, which can provide maximum digging force and fast operating cycle, and is suitable for climbing, loading and transportation operations.
(2) Gearbox variable separation pressure technology. The operator selects the required release pressure of the brake pedal. There are high and low separation pressures. The high separation pressure can maintain the engagement of the gearbox under conditions of high engine speed and high hydraulic system pressure to increase the machine's operating capacity when loading on slopes and stacking materials. Low separation pressure allows the transmission to separate at low engine speeds and low hydraulic system pressure to improve fuel efficiency when operating on level ground.
(3) Torque converter locking technology. When required, the locking system can be activated via a console switch. When the locking system is activated, if it is in third gear, the torque converter will automatically lock when the driving speed reaches 10.9 km/h; if it is in fourth gear, when the driving speed reaches 20.9 km/h, the torque converter will automatically lock. The new torque converter locking technology improves production efficiency, reduces operating cycle time, and ensures optimal fuel consumption under loading, transportation and ramp operation conditions.
(4) Gearbox lock switch technology. This technology takes the automatic transmission one step further with the gear lock function. The operator can use the push-button switch on the operating lever to keep the transmission in the required gear, making operation easier.
(5)Transmission automatic acceleration switch technology. When the bucket is inserted into the material pile, the gearbox can be shifted from second gear to first gear through the push-button switch on the operating lever to increase the digging force. When shifting into reverse gear, the transmission will automatically enter second gear. This technology increases bucket digging and penetration forces, reducing cycle times. This technology includes two new functions. One is that in automatic mode, it can be directly reduced from the fourth gear to the first gear; the other is to increase the digging force during uphill loading operations.
1.3 Automatic two-speed hydraulic control technology
This technology can match the energy of the hydraulic system with the requirements of operating conditions. Figure 1 shows the shoveling working condition. In this working condition, the auxiliary hydraulic pump is unloaded through the stop valve, and its power is used through the gearbox to increase the digging force of the bucket. Figure 2 shows the bucket lifting working condition. In this working condition, the stop valve is closed, and its hydraulic power is used to increase the hydraulic power of the working oil pump to increase the lifting speed and thereby increase the productivity of the entire machine.
1.4 Other new technologies
(1) Electronically controlled stable loading (ECSS) technology. This technology ensures that the loader can drive stably at high speeds under adverse ground conditions, and maximizes productivity by preventing bucket materials from scattering during travel, improving operating comfort and controlling performance of the vibration-damping suspension system. This technology is best suited for loading and hauling operations.
(2) Automatic lubrication technology. Precise and automatic lubrication of components such as pins and bushings during operation. Automatic lubrication can reduce unplanned daily maintenance and downtime caused by poor lubrication, thereby helping to improve productivity.
(3) Automatic material shoveling technology. The technology automates the material shoveling process, making it easier for new drivers to operate. The system provides a smooth loading cycle, continuous full bucket loading, and avoids tire slip, all without the need to operate a controller.
(4) Vehicle-mounted automatic material measurement technology. This technology uses a special weighing system to weigh hopper materials during operation, making the driver's loading more accurate and efficient. Accurate loading helps improve operating efficiency and productivity. The metering system can be installed integrated with the machinery and equipped with a printer to print out the loading results.
2 Reliability and maintenance service technology
2.1 Frame solid technology
(1) The articulated frame adopts a solid box-section structure and rigid four-section Plate tower structure. Robotic welding technology is applied to achieve deep welding and optimal integration of the frame connection points, ensuring maximum strength and long life.
(2) The engine mount adopts a box-section overall structure, and a suspension support plate is provided at the front end to form a strong and rigid structure to resist torsional deformation and impact loads.
The entire frame forms an extremely solid mounting platform for reliable mounting of the engine, gearbox, axle, cab and other accessories.
(3) The distance between the upper and lower connecting plates of the frame hinge mechanism has an important impact on the mechanical performance and component life. The extended hitch design provides optimal pin load distribution and bearing life. The upper and lower trailer pins are respectively mounted on a pair of tapered stick bearings, which distributes vertical and horizontal loads over a larger area to increase component life. The larger opening space design also facilitates maintenance work.
(4) The front frame structure adopts a four-plate welded tower structure, which can withstand the loads related to loading, turning buckets, insertion and other operating processes. It is the front axle, boom, lifting and turning buckets. Components such as oil cylinders provide a solid installation base.
2.2 Engine reliability enhancement technology
The cylinder block and cylinder head use the same gray cast iron material, and the thickness of the cylinder wall is increased to reduce noise and improve rigidity. The cylinder head is designed as a whole and forms a cross-flow structure to facilitate air flow movement. This design allows the engine to suck in cooler and cleaner air with less power.
The piston adopts an integral steel structure, and the cylinder liner uses wet, replaceable, high-strength heat-treated castings.
The radiator is a brazed aluminum structure with high strength and anti-leakage. 6 cooling fins per inch, rectangular wave design, reducing stagnation and clogging.
The electronic control module and sensor adopt a completely sealed structure to prevent the intrusion of water and dust. Connectors and wires use protective braiding to prevent corrosion and premature wear.
Each component is designed and manufactured in compliance with corresponding technical standards, ensuring optimal performance even under extreme conditions of use.
2.3 Condition Monitoring Technology
Monitoring product health is the key to maintaining the reliability of any mechanical equipment. Modern loaders come with a variety of standard and optional monitoring programs to help track the condition of the machine. The monitoring system continuously observes the working conditions of the loader. The system monitors critical engine system functions and reduces engine output when needed to protect them from damage. If any of the following conditions occurs, the monitor or front instrument panel will emit a light and sound alarm: high cooling temperature, high intake air temperature, low lubricating oil pressure, high fuel pressure, low fuel pressure, or engine overspeed.
2.4 Hydraulic sealing technology
The hydraulic hose adopts end-to-face O-ring sealing installation technology to ensure reliable connection of the hydraulic hose and prevent hydraulic oil leakage.
The buffer ring of the hydraulic cylinder is installed on the head of the hydraulic cylinder (see Figure 3) to reduce the piston rod sealing load and extend the life of the hydraulic cylinder by 30, greatly improving reliability.
2.5 Wet multi-disc fully hydraulic brake technology
The wet multi-disc brakes for driving and parking adopt fully sealed and adjustment-free technology, which avoids pollution and reduces wear and maintenance work. Dual hydraulic independent circuits are used in the brake system to provide a backup brake circuit in the event of brake system failure, thereby improving reliability. If the brake pressure decreases, the system will immediately issue a light and audible alarm. If the brake pressure continues to drop, the parking brake will automatically apply the brakes, thus providing a dual safety system for the machine. New braking technology reduces maintenance costs and improves reliability.
2.6 Comprehensive maintenance technology
Proper maintenance can reduce user expenses and costs.
To this end, a number of maintenance service convenience measures have been applied: setting up on-board hydraulic service center and electrical service center; protective and easy-to-observe monitoring instruments; ground-based maintenance points; easy access to the engine room;
Environmentally friendly sewage discharge from the outside of the machine channel design to facilitate rainwater drainage; set up a brake pad wear indicator for easy observation; maintenance-free battery design; extend the lubricating oil and filter replacement interval, the hydraulic oil filter replacement interval is 500 hours, and the gearbox oil filter The replacement interval reaches 1,000 hours; the engine and important components adopt a repairable design; global network service support, most parts around the world are available 24 hours a day, reducing customer downtime, etc.
2.7 S?O?S service system
This system can prevent major repairs and avoid substantial failures by maintaining simple maintenance. Through regular port sampling, the wear of components, lubricant properties and conditions are tracked, and the corresponding data is applied to predict wear failures before they occur. Based on the S?O?S service report, simple adjustments or replacement of parts can avoid further deterioration of the problem and major repair work, thereby maintaining the normal working condition of the machine, avoiding waiting for maintenance services, and reducing downtime. time.
2.8 Establishing an equipment management system
By opening an account at a dealer and accessing the network, the information collected through product links can be input into the computer terminal. Using fast and unobstructed machine information, you can optimize asset use, reduce safety hazards, improve maintenance management, and implement preventive maintenance strategies. The result is more operating time, lower operating costs, and greater return on equipment investment.
3. Operation comfort technology
3.1 Operation environment improvement technology
It has a spacious, quiet and efficient driving system designed with the best ergonomic characteristics. room. The machine has the best visibility at the front and rear, and the wide, distortion-free flat glass window extends to the cab floor to ensure the best visibility for the bucket. Cab noise can be reduced to 71dB. In addition, there are rainwater guide channels on the top of the cab to keep the windows clean. Anti-dazzle devices are installed on all sides to prevent the driver from being dazzled.
3.2 Driving seat technology
It has air suspension and 6 adjustment methods to adapt to various human body needs. The one-piece cast back and base design prevents cushion protrusion. The best automotive driving seat comfort lumbar support, reducing driving fatigue. The right seat armrest is equipped with an integrated execution controller for comfortable and convenient operation. There are optional heated seats.
3.3 Vibration reduction technology
The working conditions of loaders are harsh, and operating efficiency and productivity can be improved by controlling mechanical vibration. Modern loaders have adopted various vibration reduction measures: the swinging rear axle follows the ground fluctuations to maintain the stability of the cab; the cab is installed on a vibration-absorbing support to reduce the impact load on the ground; the hinge mechanism is equipped with a balance valve to prevent the frame from collide with each other; the cylinder damping slows down the bucket action at the extreme stroke to prevent mechanical vibration; the suspension control system can be used to reduce vibration and beating under loading and transportation conditions; the energy accumulator serves as a vibration absorption device to reduce the front and rear bumps of the machine. Provides smooth operation for work on uneven ground; the electronically controlled automatic anti-impact device prevents vibration and beating caused by the sudden stop of the oil cylinder; the air suspension seat control can reduce the vertical vibration transmitted by the driving floor.
3.4 Steering control technology
(1) Conventional steering.
That is, the labor-saving manual metering hydraulic steering system. Its load-sensing system only feeds power to the steering when needed. When not turning, more engine power is used to increase digging force, crushing force and lifting force, saving fuel consumption. The telescopic, tilt-adjustable steering column achieves maximum maneuvering comfort.
(2) Command control steering.
That is, the load-sensing steering system links the steering wheel and the frame's angle position to provide appropriate steering control (Figure 4). Mechanical cornering speed is proportional to steering wheel position. Under various conditions, the steering force is less than 26N, and the steering wheel of the entire machine only needs to rotate 70 degrees, while the same ordinary steering wheel needs to rotate 2 to 3 360 degrees.
The command control steering wheel includes forward, neutral, reverse switches and upshift and downshift buttons, so that the left hand is always in contact with the steering wheel. The execution controller is integrated into the right armrest of the driver's seat and can be moved with the operator.
3.5 Electronic steering control technology
The double-lever electronic shifting control system is used to facilitate shifting and reversing. The design of the transmission system avoids the separation of hands from the steering wheel when shifting gears, improving operating comfort and convenience. The electronic shift control system is combined with the automatic transmission, forced shift switch, gear hold switch and other mechanisms to provide a variety of shifting options and ensure a reasonable match between the machine working conditions and operating conditions.
To sum up, the integrated design of machinery, electricity, hydraulics and information, the refinement of design, the reasonable matching of performance parameters, high reliability, and networked online services are the key to the development of modern loaders. main direction. ;