retracting and locking seatbelts everything you need to know
Fuzz straps up to talk about classic car safety
’Seatbelts prevent passengers being thrown through windows in the event of a collision’
There can be little argument – seatbelts have saved many lives during the course of motoring history. However, it took some six decades of motor manufacturing to elapse before the three-point lap and diagonal safety belt made its appearance as a manufacturer’s standard in a production motor car; it was introduced by safetyconscious Volvo in 1958/59.
In the UK, cars manufactured from October 1964 were required to be equipped with seat belt mounting points for the driver and front seat passenger, although the actual equipping of cars with the devices was not made compulsory until 1967. At this time, the retro-fitting of postOctober 1964-manufactured cars with belts was also made mandatory.
Towards the end of the Sixties, thought had turned to the problems caused by ill-adjusted safety belts. Left loose, they could fail to restrain the car’s occupant, while lazy would-be travellers often couldn’t be bothered to manipulate belts left too tightly adjusted.
Self-retracting devices quickly rendered the static seatbelt obsolete, as the snug, perfectly adjusted fit suited most vehicle occupants, although, until 1983 front seat occupants weren’t required to wear them by law. In the back, children and other rear seat occupants remained unrestrained and vulnerable in collision situations, until common sense prevailed and, in 1987, they too were mandated to belt-up, wherever they were fitted.
Two main types of self-retracting belts are fitted to classic cars. Arguably the earliest common type was the belt-actuated inertia reel. Under normal driving conditions, the belt remained in a spring- retracted state, closely cradling the occupant’s lap and torso. Under the influence of vehicle deceleration, the occupant’s consequent inertial movement forward caused the belt to momentarily rapidly unspool, actuating a centrifugal clutch and pawl mechanism which locks the belt. This then prevented the occupant’s forward progress, restraining them and spreading the load across their body.
The second type of actuation was achieved using a device that responded directly to the actual vehicle’s deceleration. Typically, either a rolling steel ball or a pendulum weight actuated a pawl on the belt spool, stopping the belt from releasing any more of its length, thus preventing the occupant from experiencing any inertial forward movement. This latter type afforded the wearer plenty of movement when stretching to reach certain controls, or when twisting their body to view behind and perform a rearward vehicle manoeuvre.
For many classic car owners, seatbelts are an absolute must and, in the case of vehicles with solid steering columns, can prevent the driver becoming harpooned and passengers being thrown through windows in the event of a collision.
However, retro-fitting of any seatbelts to a classic car is a task best suited to a professional outfit, as it is important that all aspects regarding mounting point position, strength, belt angles, reel location and orientation are carefully considered and calculated.