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OPERATION & SERVICE MANUAL G3 Series Internal Combustion Counterbalanced Forklift Truck 2-3.5t...
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FOREWORD This manual accounts for 2-3.5t Forklift Truck of G3 series, includes its performance, structure, safe operation and regular preventive maintenance, so that operators, mechanics and supervisors of Forklift Truck correctly operate and prevent maintenance. Read and understand this manual before operating your lift truck! This manual is your guide to safe operation and regular preventive maintenance.
CONTENTS Ι. Safety Rules for Operation and Daily Maintenance of Forklift Truck ....... 1 Ⅱ. Main Specifications of Forklift Truck ............... 5 Ⅲ. Primary Assembly of Forklift Truck ................ 8 Ⅳ. The Construction, Principle, Adjustment and Maintenance of Forklift Truck ..9 1.Power System ......................
Ι. Safety Rules for Operation and Daily Maintenance of Forklift Truck It is important that driver and manager for forklift trucks remember the principle of the “first safety” and ensure the safety operation as the description in 《OPERATION & MAINTENANCE MANUAL》. 1.Delivery of Forklift Truck It must be pay attention to the following items when you deliver forklift trucks with container or trucks.
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(6)Complete the provisions before starting. (7)Release the parking lever. (8)Make trying operation of the mast for lifting, lowing and Fwd/Bwd tilting and the truck for steering and braking. 4. Operation of Forklift Truck (1)Only trained and authorized operator shall be permitted to operate the truck. (2)Wear all the safety guards, such as shoes, helmet, clothing and gloves while operating the truck.
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(11)Don’t operate truck and attachment of it at any position out of the drive seat. (12)On the high lift forklift truck, when the lift high more than 3m, it is noted that the goods on it should not fall down or the protection measures must be taken if necessary.
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Brake liquid ATF220 (wet Axle) Brake liquid(dry DOT3 Axle) Lubricating grease 3# general lithium grease(GB12981HZY4) Drive axle oil (HELI Viscosity degree 85W/90GL-5 80W/90GL-5 dry axle) (Gear oil for Applying temperature (℃) -15~+49 -25~+49 heavy duty truck) Wet bridge GL-5 gear oil special for Domestic oil HELI(CLY-SSQZY)...
Ⅲ. Primary Assembly of Forklift Truck Table of Primary Assembly of Forklift Truck Name Contents Includes engine mounting, fuel system, exhaust system and cooling Power System system (includes torque-converter oil cooling system) Hydraulic Includes hydraulic torque converter, hydraulic transmission, transmission transmission shaft and Suspension damping mechanism, etc Mainly includes main reducer and differential assembly, axle housing, Drive Axle...
1.2.3 Cautions on Cooling System Cooling system which is filled with HELI exclusive coolant free from maintenance normally before leaving the factory is used to cool engine and hydraulic powered transmission unit (hydraulic powered type forklift truck).
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● Check if the thermostat can open normally; (2) Use HELI exclusive coolant in order to keep the engine and cooling system in good condition. Change it once a year. If the coolant is bad in less than one year, change it when necessary.
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2/3 of whole height when the engine is cold. Fig. 1-1 Tank (a) Replenish the coolant with HELI exclusive one only when the engine is cool when necessary avoiding engine damage. (b) If there is no HELI exclusive coolant in an emergency, never add any additives.
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applying 10kg pressure with fingers, the specified belt flexibility is about 10mm. (5) It is prohibited to contact the radiator core directly with sharp hard objects such as if the core is dirty. Clean it with water flow or air flow with the following set pressure value.
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Tab. 1-1 check list maintenance of the engine KUBOTA V2403 Time interval for maintenance Item 100h 200h 400h 500h 1 or 2months 1year 800h 1500h 3000h 2years ☆ *Check fuel hoses and its clip ★ ☆ Change the oil inside the oil bottom shell ☆...
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1.3 Liquefied Petroleum Gas (LPG) system (integrated electronically controlled engine) The LPG system consists of an LPG cylinder, a filter, a three-way assembly (including a pressure relief valve), a solenoid valve, a carburetor, an EPR and a mixer. (FIG. 1-2) FIG.
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①Air inflation interface The interface with the inflating equipment must be connected with a special air gun. ②Safety valve When the pressure in the cylinder increases beyond the limit value, this valve will automatically open to discharge the LPG to reduce the air pressure in the cylinder; When the pressure in the cylinder is reduced to a safe level, the safety valve automatically returns to the closed state.
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1.3.2 The three-way assembly (including a pressure relief valve) The three-way assembly is installed on the cover plate of the water tank. After connected from the gas cylinder, the gas pipe is connected to the internal combustion engine compartment of the forklift.
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1.3.4 Vaporizer Vaporizer is also called "converter" because liquid LPG is converted to steam by heat in here, and the pressure is reduced to the required pressure of the engine. LPG absorbs a lot of external heat in the process of vaporization, so the hot water of the engine is fed into the shell to heat and prevent the ice from causing internal failure.
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Fig.1-4 Fuel System 1.4.2 Fuel Sensor The fuel sensor is designed to convert the remaining amount of fuel into electric current.
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Fig.1-5 Fuel Sensor The rheostat made of alloy steel wire is linked with a float. As the float moves up and down, the electric current is changed by the resistance’s changes. The fuel meter of G2 series truck is double sheets metal construction, the range of the meter finger is determined by the current scale which get across the heat element of the double sheets metal.
2. Electric System 2.1 General Description The electric system for this forklift truck is of the single-pole type, The whole truck is equipped with a standard power switch to cut off the negative battery after the truck flameout. The electric system mainly consists of the following systems. 2.1.1 Charging System This system contains generator, battery, combination meter, charging indicator, etc.
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drives the truck forward. Pull the direction switch backward, the solenoid valve (item 12) is powered on, and the solenoid valve core is connected in the opposite direction, so that the oil circuit in the reverse direction is opened, the reverse clutch works, the reverse gear is engaged, and the power is exported to drive the truck backward;...
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2.1.4 Instrument System The instrument is equipped with full LCD screen, analog pointer water temperature meter and oil meter. Display parameters are: Beijing time, engine working time, engine speed (electronic controlled engine), truck operating voltage. The indicator lights include no charging, oil pressure, zero gear, parking brake, preheating, oil-water separation, seat belt indicator, seat switch indicator, air filter blockage, left turn light, right turn light, higher engine oil temperature, low fuel level alarm (LPG truck), inhibit regeneration (for certain truck model), Brake pressure...
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Turn the key switch clockwise to the second “on” position (starting position), then start the engine. After engine starting, push the direction switch forward (that is in forward gearshift), then pedal accelerator, the forklift truck runs faster and you can begin to work. When pull the direction switch backward (that is in reverse gearshift), the backing lamp is on and the buzzer sounds.
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2.2.6 Oil Pressure Signal Before you start the engine, put the key switch to the first “on” position and the oil pressure alarm lamp is on. After engine starting, the oil pressure alarm lamp is automatically off. If this lamp becomes on while the engine is working, it indicates low lubricating oil pressure and you must stop working and check the lubricating system as soon as possible.
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be turned off automatically 3.5 seconds later, and the time of pre-heating will be under control of time relay (also called timer) and lasts to 13.5 seconds. For electronically controlled diesel engine, the preheating time is determined by the engine according to the ambient temperature. When preheating, the preheating indicator is on.
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panel. 2.2.20 Brake pressure low indicator When the indicator light on the instrument panel is on, it should stop to check the braking system. 2.2.21 Engine stops Turn the key switch to the position “OFF”, the engine will stop working automatically. 2.2.22 Automatic monitoring system of engine The instrument has the function of automatic engine monitoring.
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2.2.23 Engine failure alarm lamp (electric machine) When the point on the dashboard light is normally on, on behalf of the engine fault, should stop check and eliminate the engine fault information. When the indicator light on the instrument panel flashes, it means that the engine post-processing part is faulty. It should be shut down to check and eliminate the engine post-processing fault information.
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form of reset warping plate switch. (1) Active regeneration: when become warped plate switch in the active regeneration position, the truck is in the active regeneration mode, instrument ways treatment according to remind. When the truck is in operation, if the condition of active regeneration is reached, the truck will automatically regenerate.
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will not be active regeneration during operation. NOTE If the truck is in the restricted regeneration mode for a long time, it is easy to lead to excessive post-processing accumulation, which results in congestion, so that the truck gets into the parked regeneration stage in advance. (3)Parked regeneration When the "parked regeneration request"...
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2) How to actively regenerate The warping plate switch is switched to the active regeneration state, and when the truck reaches the active regeneration condition in operation, the truck will automatically regenerate. indicator light is lighting, the truck can continue to be manipulated during this process.
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2.3 Battery Safety notices of battery using: (1) A battery produces hydrogen gas. When making a short circuit, sparking and a fire of cigar approaching to the battery, it causes an explosion and a fire. (2) The electrolyte of battery is made of the dilute sulphuric-acid. When the electrolyte adheres to eye, skin and clothes, it causes to lose eyesight and a scald.
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Chinese and English in principle diagram 集成电器盒 后退继电器 起升电磁阀电源 控制器 空调电源 大灯开关信号 启动继电器 倒车灯电源 预热控制 integrated electric box backward relay lifting solenoid valve power controller air conditioner power lamp switch signal starting relay backward light power preheat control 中央控制盒 起升继电器 诊断接口...
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2.5 G3 series Combined Instrument 2.5.1 Startup Self-check screen 1. left steering 2. Do not charging indicator 3. Preheating indicator 4. Low engine oil pressure 5.stop light 6. ECU fault alarm 7. High temperature exhaust lamp 8. neutral gear 9. oil-water separator 10.
Set pressure 1.1~1.4MPa Weight 110kg(without oil) Oil amount HLT-9 (delicted for HELI) Oil type Mobil ATF 220 or DexronATF Ⅲ 3.1 General description Hydrodynamic transmission type forklift trucks are provided with a drive unit including a hydraulic torque converter and a powered transmission box (see figure 3-1). They feature the...
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(3) The hydraulic clutch is equipped with four pairs of specially treated paper-base friction plate and dual steel sheet, which improves the wear resistance of the friction pair; (4) Unidirectional override clutch of hydraulic torque converter improves efficiency of transferring power; (5) External coarse filter, improve the convenience of maintenance.
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pump wheel cascade under the centrifugal force (at this time, the mechanical energy is converted into kinetic energy) to the turbine cascade, so that the torque is transmitted to the output shaft. The liquid leaving the turbine changes direction under the action of the guide wheel, so that part of the liquid flows back to the pump wheel at a certain angle.
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Figure 3-2 Torque converter 3.3 Hydraulic clutch The wet multi disc hydraulic clutch distributes the pressure oil to the forward or backward clutch through the electro-hydraulic control valve to realize the forward and backward shift. All gears in the gearbox are constant mesh gears. Each clutch is composed of four spacer plates, four friction plates and a piston.
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resulting in skidding phenomenon, so that the forklift truck can move slowly, to achieve the purpose of accurate control of the forklift driving; 3.4.4 Reversing solenoid valve: It is a three-position four-way valve. The electromagnetic force generated by the solenoid valve coil controls the valve stem in the forward, neutral and backward working conditions.
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and the hydraulic transmission. Figure 3-5 Charging pump 3.7 Hydraulic oil circuit (hydrodynamic drive) When the engine is started, the oil charging pump sucks oil from the oil tank (i.e. the bottom of the transmission housing) through the oil filter and flows through the control valve. In the valve, the pressure oil is divided into two parts: one part is used for the hydraulic clutch, and the other part is for the torque converter.
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are diaengaged and the heat is taken away by the cool lubrication oil. When the inching valve is operated by the inching pedal, part or most of the oil introduced into the clutch is discharged to the oil tank through the inching valve stem. At this time, the oil circulation of the torque converter is the same as that in neutral.
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(1) Remove the half-shaft from the front wheel. (2) Shift lever should be placed in the neutral. 3.9 Position of connection ports for hydraulic oil (See figure 3-8) Figure 3-7 Measure of oil temperature and oil pressure 3.10 Reducer and differential The main reducer and differential assembly are located at the front of the gearbox.
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The differential housing is made into a left and right split type with two half-shaft gears and four planetary gears. The gaskets of planetary gear and half shaft gear are arranged between the housing of the differential and the gears and leaves a proper gap between the gears. The planetary gear is supported by a cross shaft, which is fixed to the differential housing, and driven hyperboloid gear are mounted on the right differential housing with hinged bolts.
The power from the gearbox through deceleration generates differential drive by differential, and then transmitted to the wheel through the half shaft gear and the half shaft. 4. Drive Axle(Flexible connection gearbox, Dry brake drive axle with wheel hub reduction) 4.1 General Description The drive axel mainly consists of the housing, the wheel hubs, the drum brake, the half shafts, the brakes and the hub reductor.
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1. left axle head 2. left connecting plate 3. middle axle housing 4. right connecting plate 5. right axle head Figure 4-2 3-3.5T Drive axle Housing The power transmission of the wheel hub reducer is input by the sun wheel and output by the planetary frame.
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4.2 Procedure for Hubs mounted (1)Grease the hubs for 100CC grease, then install it on the shaft. (2)Screw down the adjusting nut with a torque for about 1 kg.m and then screw it out for 1/2 turn. (3)Put the spring balance up on the bolt to measure the hubs’...
Rated speed 1500rpm Volume efficiency Weight 140kg(without oil) Oil capacity HLT-9 (delicted for HELI) Oil type Mobil ATF 220 or Dexron ATF Ⅲ 3.1 General description Hydrodynamic transmission type forklift trucks are provided with a drive unit including a hydraulic torque converter and a powered transmission box (see figure 3-1). They feature the...
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differential assembly of drive axle through the cardan joint. A suspension vibration damping mechanism is arranged between the transmission and the drive axle to effectively isolate the vibration of the internal combustion engine; (2) The hydraulic transmission has double PTO power outlet: the PTO power outlet of the working pump is directly driven by the hydraulic torque converter pump wheel, and the power is transmitted through the slender spline shaft and meshing sleeve;...
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Figure 3-1 Hydraulic transmission assembly 1. the box 2. lubrication pump 3. working pump 4. cardan joint 5. lubrication pump drive shaft 6. drive gear Ⅰ of lubrication pump 7. drive gear Ⅱ of lubrication pump 8. the forward gear clutch shell 9.
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pushing the guide wheel is generated, which makes the output torque larger than the input torque When the turbine speed increases and approaches the input speed, the angle change of liquid flow begins to decrease, and the torque of output shaft decreases. Finally, the liquid flows into the stator cascade in the opposite direction, which reverses the original reaction torque.
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3.3 Hydraulic clutch The wet multi disc hydraulic clutch distributes the pressure oil to the forward or backward clutch through the electro-hydraulic control valve to realize the forward and backward shift. All gears in the gearbox are constant mesh gears. Each clutch is composed of four spacer plates, four friction plates and a piston.
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Fig. 3-4 Backward hydraulic shift clutch 18.Reverse gear 20. reverse gear clutch friction plate 21. reverse gear clutch diaphragm 22. reverse gear clutch housing gear 24. reverse gear clutch shaft 25. return spring 29. piston 30. needle roller bearing K354220 3.4 Electro-hydraulic control valve The electro-hydraulic control valve is installed above the gearbox housing.
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force generated by the solenoid valve coil controls the valve stem in the forward, neutral and backward working conditions. There are oil inlet, forward gear clutch oil port, backward gear clutch oil port and oil return port. Figure 3-5 Electro hydraulic control valve 3.5 Transmission housing The gearbox housing includes the case and the torque converter housing.
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Figure 3-6 Charging pump 3.7 Hydraulic oil circuit (hydrodynamic drive) When the engine is started, the oil charging pump sucks oil from the oil tank (i.e. the bottom of the transmission housing) through the oil filter and flows through the control valve. In the valve, the pressure oil is divided into two parts: one part is used for the hydraulic clutch, and the other part is for the torque converter.
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are diaengaged and the heat is taken away by the cool lubrication oil. When the inching valve is operated by the inching pedal, part or most of the oil introduced into the clutch is discharged to the oil tank through the inching valve stem. At this time, the oil circulation of the torque converter is the same as that in neutral.
Figure 3-8 Measure of oil temperature and oil pressure 4. Drive axle(Soft connection gearbox, Wet brake drive axle) Table 1 Parameters of wet brake drive axle Dynamic maximum load bearing(kg) 8200 Axle load Static maximum load bearing(kg) 14760 Service brake Manual brake or power assist Brake type Parking brake...
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4.1 Genneral description The drive axle is a wet brake drive axle, which is characterized by good braking performance, high safety and efficiency, no need to adjust and maintain the brake, and low maintenance costs. It is mainly composed of main reducer and differential assembly, axle housing, wet brake assembly, hub reduction assembly, wheel hub assy and half shaft.
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gear and four planetary gear thrust washer is installed between the differential shell and the gear, and leave the gaps between the gear pair. Planetary gear shaft bearing with a cross, and cross shaft is fixed to the differential housing. The main reducer active spiral bevel gear shaft is installed on the main reducer housing through a pair of tapered roller bearings, the input flange set on the spline of the active gear shaft through the spline hole, finally tighten the lock nut, the input flange and the main reducer...
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4.3 axle housing(Fig. 4-3) Fig. 4-3 Axle housing structure 1.Left shaft head 2.Left brake housing 3.Middle axle housing 4.Right brake housing 5.Right shaft head The axle housing is composed of five parts, all of which are cast parts and assembled into a whole by bolts.
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in the state of power-off closing, and the spring compresses the friction disc and spacer tight again. Fig. 4-4 wet brake assy 1.brake housing 2.spacer 3.friction plate 4.brake piston 5.big spring 6.small spring 7.fixed plate 8.parking brake piston 9.X-ring ¢ 145.64× 3.53 10.sealing gasket 11.X-ring ¢...
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Fig. 4-5 hub reductor mechanism 1.shaft head 2.planet carrier 3.planet gear 4.planet gear bush 5.steel ball ¢ 6 6.planet gear shaft 7.sun gear 8.annular gear 9.bolt M10× 40 4.6 Wheel hub assy(fig. 4-6) Wheel hub assy is the part for power output of the end of drive axle, it outputs power to drive truck travelling.
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4.7 Wet brake integrated valve(Fig. 4-7) Pressure oil for releasing service brake and parking brake is flow to corresponding piston cavity inside the brake through forming steel pipe after integrated valve control, pressure oil that parking brake releasing required is from electric hydraulic control valve of the gearbox, the P port and A port is connected after the solenoid valve get power, The oil source from the transmission electro-hydraulic control valve enters the parking brake piston chamber, On the contrary, after the solenoid valve loses power, P port and T port are connected, and the oil from...
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dissipation of the radiator, it returns to the drive axle again. The oil suction port is equipped with an oil filter for filtering. The oil of Parking brake is from the electro-hydraulic directional control valve of gearbox, after the truck starts, when press the releasing switch of the parking brake, wet-type brake the integrated valve electromagnetic valve gets power, pressure oil flow to parking brake piston chamber of wet brake assembly from the integrated valve, release the parking brake, when there is a need to shut down or park in slope, press the releasing switch of the parking brake again,...
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rubber pad is used to reduce vibration. The left and right upper bracket is fixed on the gearbox, and the left and right lower bracket is fixed on the support plate, and the support plate is installed on the main reducer housing of the drive axle through bolts. Figure 4-10 Suspension damping system 1.Lower left bracket 2.Damper rubber 3.Washer 4.Upper left bracket 5.Support plate 6.Lower right bracket 7.Gasket 8.Upper right bracket...
Electro-hydraulic control valve Control way Electro-hydraulic proportional control Weight 140kg(without oil) Oil capacity HLT-9 (delicted for HELI) Oil type Mobil ATF 220 or Dexron ATF Ⅲ 3.1 General description Hydrodynamic transmission type forklift trucks are provided with a drive unit including a hydraulic torque converter and a powered transmission box (see figure 3-1).
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differential assembly of drive axle through the cardan joint. A suspension vibration damping mechanism is arranged between the transmission and the drive axle to effectively isolate the vibration of the internal combustion engine; (2) The hydraulic transmission has double PTO power outlet: the PTO power outlet of the working pump is directly driven by the hydraulic torque converter pump wheel, and the power is transmitted through the slender spline shaft and meshing sleeve;...
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Figure 3-1 Hydraulic transmission assembly 1. The box 2. Lubrication pump 3. Working pump 4. Cardan joint 5. Lubrication pump drive shaft 6. Drive gear Ⅰ of lubrication pump 7. Drive gear Ⅱ of lubrication pump 8. The forward gear clutch shell 9. The forward clutch spacer 10.
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pushing the guide wheel is generated, which makes the output torque larger than the input torque When the turbine speed increases and approaches the input speed, the angle change of liquid flow begins to decrease, and the torque of output shaft decreases. Finally, the liquid flows into the stator cascade in the opposite direction, which reverses the original reaction torque.
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3.3 Hydraulic clutch The wet multi disc hydraulic clutch distributes the pressure oil to the forward or backward clutch through the proportional electromagnetic valve of electro-hydraulic control valve to realize the forward and backward shift. All gears in the hydraulic gearbox are constant mesh gears.
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Fig. 3-4 Backward hydraulic shift clutch 18.Reverse gear 20.Reverse gear clutch friction plate 21.Reverse gear clutch diaphragm 22.Reverse gear clutch housing gear 24.Reverse gear clutch shaft 25.Return spring 29.Piston 30.Needle roller bearing K354220 3.4 Electro-hydraulic control valve The electro-hydraulic control valve is installed above the gearbox housing. The control valve contains valve block, constant pressure valve, forward and reversing solenoid valve, temperature sensor, seal gasket and etc.
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Figure 3-5 Electro hydraulic control valve 1. Valve block 2. Temperature sensor 3. Forward proportional solenoid valve 4. Constant pressure valve 5. Reversing proportional solenoid valve 3.5 Transmission housing The gearbox housing includes the case and the torque converter housing. In addition to the installation of hydraulic torque converter, relief valve, oil charging pump, hydraulic clutch, input shaft and output shaft and other parts, it also plays the role of oil tank.
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Figure 3-6 Charging pump 3.7 Hydraulic oil circuit (hydrodynamic drive) When the engine is started, the oil charging pump sucks oil from the oil tank (i.e. the bottom of the transmission housing) through the oil filter and flows through the control valve. In the valve, the pressure oil is divided into two parts: one part is used for the hydraulic clutch, and the other part is for the torque converter.
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hydraulic clutch are connected together through reversing proportional electromagnetic valve, Each hydraulic clutch operates independently, the gearbox is at the forward or backward gear at that time. When one hydraulic clutch works, the spacer and friction plate of the other hydraulic clutch are separated, and the heat is carried away by cooling oil lubrication.
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3.8 Position of connection ports for hydraulic oil (See figure 3-8) Figure 3-8 Measure of oil temperature and oil pressure...
4. Drive axle(Soft connection gearbox, Wet brake drive axle, Smart control) Table 1 Parameters of wet brake drive axle Dynamic maximum load bearing(kg) 8200 Axle load Static maximum load bearing(kg) 14760 Service brake Manual brake or power assist Brake type Parking brake Power brake Number of friction plates...
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through the spline hole, finally tighten the lock nut, the input flange and the main reducer housing through the oil seal, the main reducer passive spiral bevel gear is installed on the differential housing through bolts. Fig. 4-2 Main reducer and differential 1.Main reducer housing 2.Spiral bevel passive disk teeth 3.differential assy 4.lock plate 5.input flange 6.gasket 7.Spiral bevel drive gear shaft 8.bearing 30307 9.adjusting shim 10.grease baffle 11.bearing cover 12.adjusting nut 13.filter 14.block 15.fuel pipe union...
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The axle housing is composed of five parts, all of which are cast parts and assembled into a whole by bolts. The left axle head and the right axle head are left and right symmetrical parts. Only axial length difference exists between the left brake housing and the right brake housing. 4.4 Wet brake assembly(Fig.
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Fig. 4-5 hub reductor mechanism 1.shaft head 2.planet carrier 3.planet gear 4.planet gear bush 5.steel ball ¢ 6 6.planet gear shaft 7.sun gear 8.annular gear 9.bolt M10× 40 4.6 Wheel hub assy(fig. 4-6) Wheel hub assy is the part for power output of the end of drive axle, it outputs power to drive truck travelling.
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4.7 Wet brake integrated valve(Fig. 4-7) Pressure oil for releasing service brake and parking brake is flow to corresponding piston cavity inside the brake through forming steel pipe after integrated valve control, pressure oil that parking brake releasing required is from electric hydraulic control valve of the gearbox, the P port and A port is connected after the solenoid valve get power, The oil source from the transmission electro-hydraulic control valve enters the parking brake piston chamber, On the contrary, after the solenoid valve loses power, P port and T port are connected, and the oil from...
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Figure 4-9 Hydraulic principle diagram of wet brake drive axle 4.9 Suspension damping system(Figure 4-10) It is mainly used to isolate and attenuate the vibration generated by the internal combustion engine. A suspension damping mechanism is set between the gearbox and the drive axle, and rubber pad is used to reduce vibration.
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5.Support plate 6.Lower right bracket 7.Gasket 8.Upper right bracket 4.10 Smart shift module function G3 series 2-3.5t internal combustion gearbox adopt smart control, and control clutch to move forward and backward by electro-hydraulic proportional valve. inching control is operated by electronic inching pedal, which makes the operation more comfortable and light. Parking brake system adopts negative parking system with electronic control, it achieves parking and releasing by the parking brake button, which is safe and convenient.
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to reduce tire wear and improve the life of the truck. The smart control module is equipped with a special TCU controller, which is installed on the right side of the truck frame. According to the state of the truck and the operator's operation instructions, the controller control the smart functions such as gear position of the transmission system, parking and HAC.
5. Steering System 5.1 General Description The steering system mainly consists of steering handwheel, steering frame, driving shaft and steering unit. The steering handwheel is connected with steering unit through the driving shaft. The steering frame can tilt forward or backward to a suitable position ensuring the driver’s easy control of the steering handwheel.
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Fig.5-2 Cycloid Gear Type Powered Steering Unit (1)Spacing sleeve (2)Valve body (3)Valve core (4)Interlock shaft (5)Spring piece (6)Joint sleeve (7)Rotor (8)Stator (9)Valve sleeve 5.3 Inspection on Reassembly of Steering System (1) Check the forces necessary to turn the steering handwheel to right and left until it can’t be turned any more to see if they are identical each other and check the operation of the steering handwheel for smoothness during above operation.
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5.4 Steering System Troubleshooting Problem Analyses of Trouble Remedies Pump damaged or breaking down Replace Fail to Turn Flow-divider blocked or damaged Clean or replace Handwheel Hose or joint damaged or pipeline blocked Clean or replace Too low oil pressure from flow-divider Adjust pressure Air in steering oil circuit Exhaust air...
6. Steering Axle 6.1 General Description The steering axle is of section-boxed welded construction type (Fig.6-1). It includes axle body, steering cylinder, tie rod, knuckles and steering wheels. The steering trapezium is made of cranks and blocks. When pressure oil move the cylinder piston rod, the tie rod revolve the knuckles, then the truck may be steered.
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1. Oil seal 7. Tapered roller bearing 13. Needle bearing 19. Tie rod 2. Needle bearing 8. locknut 14. Oil seal 20. hinge pin 3. Thrust bearing 9. Hub cover 15. King pin 4. Oil seal 10. Steering knuckle hub 16.
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Fig.6-5 Fill Up Grease and Pre-load Adjustment...
7. Braking System 7.1 General Description Brake system is divided into parking brake and service brake. Service brake is manual braking, It consists of brake pedal mechanism, brake pump, driving brake and pipeline. Parking brake is a negative spring brake, which consists of parking brake switch, hydraulic oil circuit, parking brake valve and parking brake.
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Figure 7-2 Structure diagram of Manual Braking 7.1.1 Braking Pedal of service brake The braking pedal unit is mounted on the front panel through bracket as shown in Fig.7-1 and Fig.7-2. When the pedal moves, it push the rod to course the piston moves and the pressure of the oil circuit increased.
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the return port until the primary cup blocks up the return port. After the primary cup passes through the return port, the brake fluid in the cylinder is pressurized and opens the check valve, Thus, the brake pipe flows to the service brake piston cavity on both sides of the wheel, and the service brake piston moves outward to make the brake friction plate contact with the spacer, so as to achieve the effect of deceleration or braking.
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7.1.4 Height of the brake/inching pedal Fig.7-4 Height of the Brake Pedal Free play of the inching pedal is 1-2mm. Adjust the initial height between the inching pedal, brake pedal and the floor cushion, when it reaches 105mm, lock the pedal by lock nut, press the inching pedal for 20mm.
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(c) Turn the switch to make the clearance about 1mm. (d) Make sure that when you press the brake pedal the brake lamp light at the same time. 7.2 Maintenance of the Brake Because of the brake friction disc is woking at the oil bath environment, so wet brake is free of daily maintenance.
Hydraulic oil is refined from mineral oil with various additives (anti-wear, anti-oxidation, high temperature resistance, etc.). At present, 1~ 10T forklift trucks use special hydraulic oil that dedicated for HELI. 8.1.2 Hydraulic pump Hydraulic pump is power element. It changes the mechanical energy into the pressure energy of hydraulic oil as the power source of the hydraulic system.
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a direction control valve, which is the control element of the hydraulic system. Figure 8-2 Multi-way valve Multi-way valve structure The multi-way valve is segmented, which is composed of three major parts: the oil inlet piece (the shunt valve is installed in the inlet), the oil return piece and the spool valve piece. And these three parts are assembled together by three bolts.
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disappears, under the action of spring pressure, spool valve can automatically restore to neutral position. keeping the spool valve in the neutral position automatically without the operator controlling can increase the reliability of the work and reduce the labor intensity of the driver. Multi-way valve operation (1)Neutral position(see figure 8-3)...
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Figure 8-4 Push spool valve in Figure 8-5 Pull spool valve out Work of Tilting self-lock valve Tilting self-lock valves are used to prevent vibration of the mast (due to negative internal pressure that may be generated in the tilting cylinder). It also avoids the danger of accidentally tilting the mast by misaction (hitting the tilting lever) when the engine is turned off.
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Figure 8-6 Push spool valve in Safety valve Figure 8-7 Safety valve The main safety valve consists of the main valve and pilot valve B, when the multi-way valve reversing, high pressure oil of Q cavity and work organization is communicated (such as lifting cylinder, tilting cylinder), Pressure oil is applied to pilot valve B through fixed throttle hole D and E, when the system pressure is greater than the setting pressure, pilot valve B is opened, then F cavity pressure is reduced, the main valve core A move to the right, make the...
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pressure value of steering system is obtained directly by the balancing of liquid pressure and spring force. When operating the steering wheel, the oil chamber M is connected with the high pressure oil circuit. When the system pressure is greater than the spring pressure, the spool N moves to the right, and the pressure oil passes through the low pressure oil circuit from the T chamber, so that the M chamber is unloaded to ensure the stability of the steering system pressure, and the adjusting screw K can be used to adjust the stable pressure value of the system.
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right chamber of the cylinder (depending on the direction of rotation) through the rotary valve and the rotary stator metering device. The oil from the stator is proportional to the number of turns of the steering wheel. (Generally forklift steering wheel number in 4~5 circles). Manual steering: when the engine is flameout, the oil pump cannot supply oil, but the steering can be realized manually.
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8.1.5 Lifting cylinder The lifting cylinder adopts plunger hydraulic cylinder. It consists of a cylinder body, a plunger rod, a plunger, a guide sleeve, a seal and a cut-off valve. Guide sleeve and cylinder connect through thread, equipped with oil seal, dust ring, O-ring and vent plug; The plunger is equipped with L-type supporting ring and plunger rod with screw connection to prevent loosening.
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Fig.8-12 Cut-off Valve ▲Working Principle of the Cut-off Valve When moving back to oil tank the pressure oil in the lifting cylinder will pass through hole A and hole B on the valve spool. If the flow velocity of the oil that passes the hole is less than the set value of the valve, the pressure difference between the front and back of the valve spool shall be less than the spring force.
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in the “down” position, the oil flows in the reverse direction. When the oil passes the orifice plate (5) and a pressure difference generates between the chambers A and B, the pressure difference overcomes the force of the spring (2) and moves the valve core (7) right, thus the oil flow being decreased by narrowing of the hole D and C, and reduces the oil flow passing through the orifice plate (5).
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from the cylinder tail, moving the piston forward and causing the mast assembly to tilt forward. When the tilt lever is pulled backward, high-pressure oil enters into the cylinder body from the guide sleeve and moves the piston backward, tilting the mast backward. Fig.8-15 Tilt Cylinder (1) Ring (2) Dust ring...
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1.Steering gear 2.Steering cylinder 3.Speed Limit Valve 4.Lifting cylinder 5.Cut off valve 6. Tilt cylinder 7. Multi-way valve 8. Oil filter 9. Hydraulic pump 10.Oil filter The high pressure oil from oil pump is divided into two parts by priority valve of multi-way valve: part of high pressure oil flow to the main lines of tilting or lifting oil cylinder, The other part is connected with the steering device LS oil port through the multi-way valve with very little flow when the steering operation is not carried out, controlling the multi-way valve priority spool,...
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Fig.8-17 Main Pump (1)Pump body (2)Driving gear (3)Driven gear (4)Front cover (5)Rear cover (6)Lining plate (7)Seal ring (8)Ring (9)Oil seal (10)Snap ring (11)Bolt (12) Washer Disassembly ▲Cautions: (a) Before disassembly, make sure if there exits oil leakage at the joint interface between oil seal, pump body, pump cover and on other parts.
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(1)Clamp the flange part of the pump onto the clamp table and fixed well as shown in Fig.8-18. Note: for easy installation, use oily pen to make marking at the rear-end cover, front-end cover and the driving gear of the Fig.8-18 pump body.
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(6) Dismantle the driving gear. Note: make marking on bearing side of the driving gear. (as shown in Fig.8-23) Fig.8-23 (7) Press down the front-end lining plate to dismantle the driving gear. (as shown in Fig.8-24) Fig.8-24 (8) Remove the lining plate. Note: make marking on the driving gear side on the front lining plate.
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8.2.2 Inspection The disassembled parts except rubber parts should be washed with gasoline (Except rubber parts). (1) Pump body inspection If the scraping trace is up to 1/2 long of the inner periphery, it indicates that the bearing and gear shaft are subject to excessive wear, replace the pump body.
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8.2.3 Installation (1) As shown in Fig.8-32, fix the front-end cover on the clamp table. Fig.8-32 (2) Fix a new sealing ring onto the pump front-end cover. Note: do not twist. Fig.8-33 (3) Install a new snap ring onto the pump front-end cover with mounting direction as shown in Fig.8-34.
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(5) Mount the lining plate at groove place of the front-end cover, be careful not to mistake the oil-suction port with the oil-discharging port and note direction of the lining plate. Fig.8-36 (6) Mount the driving gear into the pump body with its spline side pointing down.
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(10) Make the sealing ring of back-end cover pointing down and mount it into the pump body. Take care not to mistake the oil-suction port with the oil-discharging port. Fig.8-41 (11) Mount and tighten the connection bolt to required torque at 9~10kg.m. Fig.8-42 (12) Take off the pump from the clamp table, put the lubrication grease on outer ring and lip...
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bottom. c) When the oil pressure is different from the specified value, loosen the locking nut of the relief valve and adjust the adjusting screw to the specified value by turning the adjusting screw left or right. Turn the screw left at high pressure, right at low pressure. d) Tighten the nut after finishing adjustment.
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Check the cause of bubbles first and then take There are bubbles in the hydraulic oil action Oil leakage of Oil damage of oil pump, O-ring or Replace faulty parts oil pump sliding surface wear of oil pump The carriage Excessive wear clearance between valve Replace rod with required clearance drops...
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Relief valve pressure is lower than the working pressure or relief valve is stuck Adjust relief valve pressure or clean by dirts, the steering is light with light or relief valve. empty load, and heavier with increasing the load. The viscosity of oil is too large Use the recommended viscosity oil.
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Excessive load. Lift load according to requirements. Leakage inside the piston YX-ring Replace YX-ring seal. Excessive seal of the lifting cylinder. Downwards Inner leakage of A type spool valve of Replace the O-ring seal inside the spool Sliding for the control valve. valve.
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seal of piston rod of the tilting cylinder. Oil leakage due to the damaged YX-ring Replace. seal and O-ring seal in the pilot sleeve. The main safety valve is stuck or open Clean or replace the safety valve normally Inablity to Add oil between the upper and lower The oil is insufficient in oil tank.
9. Lifting System 2-3.5t Type: Rolling type, JB-shaped inner mast, C-shaped outer mast with free lift, 2-stage telescopic mast. Cross section of outer mast: Cross section of inner mast: Fig.9-3 Fig.9-4 Roller: Φ119.2mm Main Roller Side roller group Ⅰ Φ58mm, Width: 30mm Side roller group Ⅱ...
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9.1 General Description The loading system is of the two-stage, rolling telescopic mast type and consists of inner mast, outer mast and carriage. 9.2 Inner and Outer Masts The inner and outer masts are welded parts. The bottom of outer mast is connected with the frame support through supporting.
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rollers group Ⅰ. They are separately mounted on the upper end of the outer mast(2), lower end of the mast(2). There are 2 side roller group Ⅱ, which are installed on both sides on the upper end of the column plate of the carriage; There are 4 composite rollers with side rollers, which are installed on the middle end of the column plate of the carriage (2) and both sides of the lower end (2).
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9.5 Maintenance 9.5.1 Adjustment of Lift Cylinder When replace the lift cylinder, inner mast or outer mast, we shall readjust the stroke of the lift cylinder as following. (1)Install the piston rod in the upper beam of the inner mast without shims. (2)Lift the mast slowly to the max.
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(3) Make the fork down to the ground and tilt backward fully. Adjust the adjusting nut for the end nipple of the upper chain and make the two chains’ tightness equal. Fig.9-7 9.5.3 Carriage Rollers Replacement (1) Fork a tray on the fork and let the truck parking on the horizontal ground. (2) Make the fork and the tray down to the ground.
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(4) Disassemble the fitted bolts for the lift cylinder and the inner mast. Hang up the inner mast not to loose the shims for the top of the piston rod. (5) Disassemble the connecting bolts for the lift cylinder and the bottom of the outer mast. Disassemble the lift cylinders and the oil pipes between the two cylinders without loosen the oil pipe joints.
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OPERATION & SERVICE MANUAL www.helichina.com Add/No.668, FangXing Road, Hefei, China Post Code/230000 Customer Service Hotline/4001-600761 Service Tel/+86-551-63648005,63689000 S364-1-2021 E-mail/heli@helichina.com All rights reserved...
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