Types Seat belt

1 types

1.1 two-point

1.1.1 lap
1.1.2 sash


1.2 three-point

1.2.1 belt-in-seat (bis)


1.3 4-, 5-, , 6-point
1.4 seven-point

types
two-point

a 2-point belt attaches @ 2 endpoints, , invented in 1900s jack swearingen of louisville, kentucky.

lap

a lap ( 2-point ) belt in airplane

a lap belt strap goes on waist. commonly installed type of belt prior legislation requiring 3-point belts, , found in older cars. coaches equipped lap belts (although many newer coaches have three-point belts), passenger aircraft seats.

university of minnesota professor james j. (crash) ryan inventor of , held patent on automatic retractable lap safety belt. ralph nader cited ryan s work in unsafe @ speed , in 1966 president lyndon johnson signed 2 bills requiring safety belts in passenger vehicles starting in 1968.

until 1980s, three-point belts commonly available in front outboard seats of cars; seats fitted lap belts. evidence of potential of lap belts cause separation of lumbar vertebrae , associated paralysis, or seat belt syndrome , led progressive revision of passenger safety regulations in developed countries require 3-point belts first in outboard seating positions , in seating positions in passenger vehicles. since september 1, 2007, new cars sold in u.s. require lap , shoulder belt in center rear seat. besides regulatory changes, seat belt syndrome has led tremendous liability vehicle manufacturers. 1 los angeles case resulted in $45 million jury verdict against ford motor company; resulting $30 million judgment (after deductions defendant settled prior trial) affirmed on appeal in 2006.

sash

a seat belt , buckle

a sash or shoulder harness strap goes diagonally on vehicle occupant s outboard shoulder , buckled inboard of or lap. shoulder harness may attach lap belt tongue, or may have tongue , buckle separate of lap belt. shoulder harnesses of separate or semi-separate type installed in conjunction lap belts in outboard front seating positions of many vehicles in north american market starting @ inception of shoulder belt requirement of u.s. national highway traffic safety administration s federal motor vehicle safety standard 208 on 1 january 1968. however, if shoulder strap used without lap belt, vehicle occupant submarine , or slide forward in seat , out under belt, in frontal collision. in mid-1970s, 3-point belt systems such chrysler s uni-belt began supplant separate lap , shoulder belts in american-made cars, though such 3-point belts had been supplied in european vehicles such volvos, mercedes, , saabs years.

three-point

a 3-point seat belt

a 3-point belt y-shaped arrangement, similar separate lap , sash belts, unitized. separate lap-and-sash belt, in collision 3-point belt spreads out energy of moving body on chest, pelvis, , shoulders. volvo introduced first production three-point belt in 1959. first car three-point belt volvo pv 544 delivered dealer in kristianstad on august 13, 1959. however, first car model feature three-point seat belt standard item 1959 volvo 122, first outfitted two-point belt @ initial delivery in 1958, replaced three-point seat belt following year. three-point belt developed nils bohlin had earlier worked on ejection seats @ saab. volvo made new seat belt design patent open in interest of safety , made available other car manufacturers free.

belt-in-seat (bis)

the bis three-point harness shoulder belt attached seat itself, rather vehicle structure. first car using system range rover classic. fitment standard on front seats 1970. cars renault vel satis use system front seats. general motors assessment concluded seat-mounted 3-point belts offer better protection smaller vehicle occupants, though gm did not find safety performance improvement in vehicles seat-mounted belts versus belts mounted vehicle body.

bis type belts have been used automakers in convertibles , pillarless hardtops, there no b pillar affix upper mount of belt. chrysler , cadillac known using design. antique auto enthusiasts replace original seats in cars bis-equipped front seats, providing measure of safety not available when these cars new. however, modern bis systems typically use electronics must installed , connected seats , vehicle s electrical system in order function properly.

4-, 5-, , 6-point

bucket seat combined schroth 6-point harness

five-point harnesses typically found in child safety seats , in racing cars. lap portion connected belt between legs , there 2 shoulder belts, making total of 5 points of attachment seat. 4-point harness similar, without strap between legs, while 6-point harness has 2 belts between legs. in nascar, 6-point harness became popular after death of dale earnhardt, wearing five-point harness when suffered fatal crash; first thought belt had broken, , broke neck @ impact, teams ordered six-point harness in response.

seven-point

aerobatic aircraft use combination harness consisting of five-point harness redundant lap-belt attached different part of aircraft. while providing redundancy negative-g manoeuvres (which lift pilot out of seat); require pilot un-latch 2 harnesses if necessary parachute failed aircraft.