Steering rack Installation Guide
The power steering is the rotary valve structure (hydraulic directional machine)
It is generally performed by rotating the engine with the engine, and the oil is pumped out of the tank to the power steering valve. When the control valve is in the middle of the normal opening, the oil is directly returned to the steering tank through the control valve.
1. Middle position
Car straight line driving (steering wheel fixed), oil pump to supply hydraulic oil from the oil inlet, after rotary valve of pre-opening gap. Flow around two working chamber, because the rotary valve, thus working hydraulic steering gear two same does not produce power, the hydraulic oil from the oil return back to the tank mouth, see the principle diagram of the gear and rack type power steering gear.
2. Steering process
When turning the steering wheel, the pre-opening gap between the input shaft and the valve sleeve changes, resulting in the oil pressure difference between the hydraulic oil flowing to the two working chamber and the steering resistance. The oil pressure difference is used to push the rack piston on the rack piston to overcome the steering resistance and produce the displacement, thus driving the steering rod to realize the front wheel steering.
3. Return process
When the steering is completed, the force on the steering wheel disappears. Torsion bar within the power steering gear and the car front wheel automatically back to the positive moment, under the action of two poor working oil chamber of hydraulic steering disappear, sports steering wheel to the straight position, until back to the car driving straight position.
4. Road sense effect
The road sense effect is the ability to turn to feeling. When the driver forces on the steering wheel, it also ACTS on the torsion bar on the steering gear to produce torsional deformation; The deformation depends on the steering resistance of the wheel. When the steering resistance is large, the deformation is also increased. Therefore, the driver can judge the change of the steering resistance according to the size of the force on the steering wheel, so as to obtain the "road sense" effect.
Principle of the steering mechanism (as shown in the figure)
The steering gear is pinion, and the back of the gear has an adjusting semicircle, which is pressed against the rack by spring pressure, so that the rack is always in contact with the pinion with appropriate force. The clearance of the steering mechanism is the adjustment of the semicircle and spring automatically on the lower side of the rack
Schematic diagram of structure principle of gear rack power steering device.
2) check the oil pressure.
The failure of the power steering system is usually related to the difficulty of steering with no auxiliary force. In this case, if it is to be repaired, the first thing to do is to figure out whether the problem is on the pump or on the case. To do this, a pressure gauge can be used to check the car
.
1, 2, adjusting screw adjusting nut 3, 4, adjusting spring adjustment round 5, round gasket 6, 7, end cover nut shell bearing under 8, end cover screw 9, 10, 11 oil cylinder assembly, shell under long tubing 12, short tubing 13, 14 15, rack, coupling assembly machine foot dust cover 16, 17, 18, inner tie rod nut bar hoop assembly (19, 20, valve, valve gear bearing oil seal, valve 21 tooth 22, 23 body, the body king plastic ring on the 24, 25, valve core bearing shell, shell oil seal on 26 and 27, 28, up and down on the shell shell connecting screws, 29, 30, piston rack and plastic ring king 31 32, piston, piston o-rings, 33, live chandrasekhar spring 36, 34, 35, sliding bearing high pressure oil seal oil cylinder oil seal 37, oil cylinder oil seal iron iron set 1 set of 2 38, cylinder spring
Its main structural parameters are as follows:
Ex. :
| Transmission Ratio | 46.67 |
| Center Distance | 20mm |
| Total Turning side to side | 3.3±0.1 |
| Toute | 158mm |
| Laps | 1.85 |
| Direction | Left |
| The highest working pressure | 8.5Mpa |
| Input Torque | 4-6N.m |
| Output | 8157N |
Nor.Diameter cylinder | Nor.rack diamter |
φ35 φ36 φ38 φ39 φ40 φ41 φ42 φ42.5 φ43 43.5 φ44 φ45 φ46 φ48 φ49 φ50 φ52 φ53 φ55 φ56 | φ22 φ23 φ24 φ25 φ26 φ27 φ27.7 φ28 φ30 φ32 φ35 φ38 |
| The fault | The main causes. | Elimination method |
| To difficult | The tyre pressure is low and the engine speed is not steady. | Inflate the tyre and adjust the performance of the engine. |
| The main pin Angle is too large. | Check the front wheel alignment. | |
| Wear of the steering system universal joint. | Replace the steering system universal joint. | |
| Lower arm ball socket wear. | Replace the lower arm ball socket. | |
| The steering column is stuck. | Check the steering column. | |
| The piston cylinder of the steering gear is too worn, the oil seal is poor, and the rotary valve is stuck. | Repair the steering gear. | |
| The oil pump is too low. | Replace the oil pump | |
| Heavy vehicle overload | lightening | |
| There is foreign body in the steering system to cause the steering pump flow control valve lag. | Check the steering gear, steering pump control valve and clean the entire power steering system. The inside of the oil cup is too dirty, the filter is blocked or the oil cup is low, it is necessary to replace the oil cup. | |
| The belt of pump is loose, sliding or pump mounting position is loose. | Adjust the tension of the belt as required. Fastening the connecting screw for each part. | |
| There is air in the power steering system. | Provide air to the steering system as required. | |
| The bolts of the connecting parts of the tubing are loose, causing the diversion fluid leakage. | Check the connection parts of the tubing, Tighten each connection bolt. | |
| Unilateral steering heavy | Unilateral tire pressure is not enough. | inflatable |
| The diverter leaks only in one direction. | Repair the steering gear. | |
| The rotary valve is not in the middle position. | ||
| Left or right fixed pressure can't be built. | Replacement of seals | |
| Hit both sides quickly. Steering wheel heavy | Turn to oil outlet and turn to oil pump. Inlet and steering pump and engine. The joints of the air are drawn in. | Tighten tubing joints or replace seals. |
| The steering pump flow is too low. | Change steering pump | |
| Steering wheel free travel. Big, jitter | The steering wheel and steering shaft are loose, The steering gear assembly is too loose. Fixed snails for steering and steering brackets. Bolt looseness | Tighten the loose part. |
| Wear of front wheel bearing. | Replace the front wheel bearing. | |
| Main shaft fork or intermediate shaft fork wear. | Replace the main shaft fork or intermediate shaft. | |
| Lower arm ball socket wear. | Check the lower arm ball socket. | |
| Steering rod assembly or outer ball. Head wear | Replace the steering rod assembly or. Ball head assembly | |
| Steering gear maladjusted or damaged. | Adjust or repair steering gear teeth. | |
| The deflector overheats. Environment temperature is above 65 ° C) | Excessive pump flow | Replace the oil pump |
| Tubing bending radius is too small or internal. The resistance causes the fluid to flow poorly and heat. | Replace the tubing | |
| Turn to limit position at both ends for more than 5 seconds. | Avoid turning to extreme positions at both ends. | |
| Steering blanketed | Steering system components loose or worn. | Tighten or replace. |
| The steering tank is lower than the oil mark. | refuel | |
| Turn to universal joint locking bolts to loosen. | Tighten the bolt | |
| Negative return | Steering gear maladjusted or damaged. | Adjust or repair steering gear. |
| Power steering strap slack. | Adjust the belt | |
| Low hydraulic oil level in reservoir. | Check reservoir | |
| Power steering has trouble check. | Power steering | |
| Improper inflation of tyre | Inflate the tyre to the specified pressure. | |
| Wheel positioning is incorrect. | Check the front wheel alignment. | |
| The steering column is stuck. | Check the steering column. | |
| Abnormal noise | The steering shaft is slack. | Tighten the steering rod system. |
| Wear of the steering system universal joint. | Replace the steering system universal joint. | |
| Steering gear maladjusted or damaged. | Adjust or repair steering gear. | |
| The car is on a flat road. The surface is run in two directions. | The steering wheel head section is loose or the front wheel is improperly positioned. | Adjust the front wheel alignment and turn the ball head. |
| The pretension of the rack in the steering gear is misaligned. | Adjust or maintain the pretensioning of the steering gear. | |
| The steering rod is distorted or overworn. | Replace the steering gear. | |
| The power steering fluid produces a milky foam. | There is air in the steering system. | Remove the air and check for leaks. To solve |
| There is fluid leakage in the steering system. | Check the oil cup and lubricate the oil cup. | |
| Turn on the noise in the system. | There is air in the steering system. | Remove the air and check for leaks. To solve |
| The steering tube has no noise reduction function. | High and low pressure tubing with noise reduction function. | |
| The diverter valve assembly is poor. | Replace the steering gear. | |
Steering system internal cleanliness, resulting. | Cleaning and inspecting the tubing, oil cup, oil pump, |
