headlamp also known headlights, it is an important component assembly guarantee safe operation of the car, mounted on the car side of the head for illuminating the road at night driving, two lights and four-lamp system points. The farther from the lamp as a headlamp, a light distribution characteristic as possible, with the vehicle safety performance higher. In the car, in the past that the removable incandescent light bulbs and incandescent headlamps are vacuum has been eliminated and replaced by halogen headlamps, swept the world a few years of effort, has become the main national car headlights. Since the headlamp lighting effects directly affect the operation of traffic safety and driving at night driving, traffic management and therefore the world more than the law provides for its line lighting standards.
1. Headlamp Category
(a) can be divided according to their structural characteristics
1. The fully enclosed headlamp
2. semi-closed headlamp
(B) and its installation can be divided into
1. exterior headlamp
[ 123] 2. built headlight
3. The headlamp may Tibetan
(c) can be divided according to their shape
1. round headlight
2. The number of square headlamp
3. The oblong headlamp
4. The profiled headlamp
(iv) its automotive equipment headlamp It can be divided into
1. The two lamp headlamp system Ltd.
2. The headlamp system four-lamp system
3 with auxiliary headlamp the headlamp system
2. headlamp beam adjustment and testing
(a) adjustment and test methods
1. adjusting the beam in the test should be carried out in a dark environment front screen, meter inspection or adjustment. Adjustment and inspection site should be flat, perpendicular to the screen and site. It should be adjusted in no-load test car carried out under conditions to take a driver.
2. The light beam irradiated position I represents an offset value. Refers to an offset value or cutoff line beam center angle adjustment of the distance moved in 10m (dam) from the screen in a horizontal or vertical line h-h V left and V left (V a V Right Right) line direction.
3. Test adjustments on the screen. The adjusted test parked and placed before the screen and the vertical screen, the headlights from the screen reference center * 10m, and the screen and the line h-h headlamp reference center distance H from the ground contour: were measuredLeft, right, and low beam illumination beam orientation of the horizontal and vertical offset values.
4. Adjust the meter for inspection. The test car is adjusted by a predetermined distance and opposing meter; check left, right, and low beam illumination beam orientation of the horizontal and vertical offset values from the measuring instrument of the screen, respectively.
(b) adjusting and inspection requirements
1. The vehicle test apparatus with a predetermined adjustment of various types of low beam lamp on the screen. Class A lamp: automobiles, motorcycles fitted with, respectively, the photometric characteristics which meet the GB 4599-84, headlamp predetermined GB 5948-86. Class B lamp: automobiles, motorcycles allows to use a transition headlight. Class C Light: headlight Tractors transport means.
2. The four-lamp system fitted with headlamps which light of a single far-adjusting beam lamp on the screen, requires less than 10 percentage of the center of the beam center of the lamp at a distance from the ground line hh, namely: 0.1Hcm / dam 100m from the very center of the beam landing. V left and V in a left, right line V-V and right to left, right offset: the left light to the left unbiased greater than 10cm / dam (0.6deg;); right unbiased greater than 17cm / dam (1deg;). Left or right partial right light not greater than 17cm / dam (1deg;).
3. The vehicle loaded with the high beam lamp to adjust the two-beam-based low beam, so that in accordance with Table 1. Forward
4. The adjusted beam on a flat road which is much luminous ships should be as clear obstacles away car approximately 100m; low-speed transportation vehicle wheel tractor, which is much luminous front vehicle should be as clear obstacles away about 35m.
5. When the vehicle load. Headlamp beam axis inclined upwardly, so that the cutoff line corresponding to the beam center angle or offset value is changed on the screen, when the variation is greater than 0.05 ~ 0.15H when unloaded (depending on the vehicle), compliance should be adjusted so that provision
2.2.1,2.2.2 paragraph
3. Headlamp using
There headlight low beam function, the low beam lamp is close when using high beam, illuminate the road far vision open. Rational use of car headlamps should be done will become low beam, promptly after the car will change back to high beam, through the intersection and overtaking should be prompted to transform the distance light.
1. The forward traveling beam for illumination when no vehicle or other vehicle trailing. .
2 low beam illumination for close encounters when two vehicles; is also used in the following nighttime.
a. Trailing the preceding vehicle and the leading vehicle when the distance from 30 to 50m.
b. Driving on city roads have street lighting.
c. Before the adoption of traffic control post.
3 foggy day, when snow, heavy rain or dust with blurred region, may be used instead of the low beam light fog;. Instead of night allowed to use low-beam light fog.
4. Headlight circuit failure analysis
a, Symptom
1. After turning on the headlamps when driving at night, in the bright headlamps 2h start, but then gradually darkens, and the brightness changes with the engine speed varies. At this time, as the engine stall, the engine can not be started with the starter, it is the first two days may not start the engine with the starter.
2. After switching on the headlights, their hot wire, plastic or Bakelite blow burning smell occurs, severe enough to cause burning or harness car fire.
3. Immortal not lit headlamp headlamp when the headlamp is turned on or off the headlamp.
4. The fuse is blown, ammeter burn, even based charging circuit is also burned.
Second, the cause of the malfunction
The above-described failure more common on automotive four-lamp system, mainly due to changing the blind power headlamp bulb. Because in the auto parts market quality headlamp is not guaranteed, their lack of luminous intensity, a lot of drivers and maintenance personnel for convenience and the pursuit of large luminous intensity headlamps, and some inspectors in order to make the headlamp lighting emission intensity reaches a predetermined value, are replaced by the above-described original car headlight bulb lamp power, the result is: headlight luminous intensity reached, but the fault headlight circuit has greatly increased, and sometimes damaged a charging circuit system.
Most four-lamp system vehicle equipment at the factory of the headlight lamp power 45W / 50W, the headlight line divided left and right road 2, each line 15A with safety fuse, wire cross-sectional area were ge; 1.5mm2, therefore, the current on each line (8.3A) is within the allowable range, the fault circuit headlamp few. After the power switch to the headlamp bulb (100W), the current lines are on each headlamp fold increase (up to 16.6A), the headlights severe overload the line, which may lead to the following various faults.
1. Serious loss of battery power. After the headlamp is turned on, battery powered generator for a joint, therefore, normal cars at night beginning with the luminance of the left and right headlight 2h, and thereafter can not continue because the battery power, the luminance decreases headlamp , and varies with engine speed, after the engine starter to start the engine can not stall.
2. Heating wire, so that the line resistance is increased, the emission intensity decreases headlight, the headlight line due to severe the wire insulation to melt and short circuit even burning car or fire accidents.
3. Or a combination of line light switch, relay contacts or bonding generating ablation, can open or close a circuit.
4. Headlight fuse is blown lines in the darkness the vehicle in front.
5. When using more electrical generator overload duration is too long, the diode and the coil of the generator may be damaged, so that the generator can not generate electricity.
Third, the maintenance considerations
1. When replacing the headlight lamp, automobile factory should use the original model specified with similar power or headlight bulbs, such as switching to a vacuum bulb or bulb H4, H4 bulb should be used 55W / 60W or 75W / 75W vacuum bulb, and only the left and right symmetrically with a respective transducer, in order to avoid overloading the line.
2. Loss of charged battery must be charged in order to restore its power supply capacity.
3. When the red light headlamp, should check the grounding of the headlamp, and each connection line and the connection point of the line generator and the battery, and carefully each repair for the relays and switches corrosion, ablation or contact bonding.
4. When the headlamp reflector bleak, pitting, corrosion or peeling of plating when the mirror, the headlamp should be replaced.