Council Directive of 28 June 1977 on the approximation of the laws of the Member States relating to safety belts and restraint systems of motor vehicles (77/541/EEC) (repealed)

[F1 ANNEX VII U.K. DESCRIPTION OF TROLLEY, SEAT, ANCHORAGES AND STOPPING DEVICE

Textual Amendments

F1 Substituted by Commission Directive 2000/3/EC of 22 February 2000 adapting to technical progress Council Directive 77/541/EEC relating to safety belts and restraint systems of motor vehicles (Text with EEA relevance).

1.	TROLLEY For tests on safety belts the trolley, carrying the seat only, shall have a mass of 400 ± 20 kg. For tests on restraint systems the trolley, with the vehicle structure attached, shall have a mass of 800 kg. However, if necessary, the total mass of the trolley and vehicle structure may be increased by increments of 200 kg. In no case shall the total mass differ from the nominal value by more than ± 40 kg.
2.	SEAT Except in the case of tests on restraint systems, the seat shall be of rigid construction and present a smooth surface. The particulars given in Figure 1 hereto shall be respected, care being taken that no metal part can come into contact with the belt.
3.	ANCHORAGES The anchorages shall be positioned as shown in Figure 1. The circular marks which correspond to the arrangement of the anchorages, show where the ends of the belt are to be connected to the trolley or to the load transducer, as the case may be. The anchorages for normal use are the points A, B and K if the strap length between the upper edge of the buckle and the hole for the attachment of the strap support is not more than 250 mm. Otherwise, the points A 1 and B 1 shall be used. The structure carrying the anchorages shall be rigid. The upper anchorage must not be displaced by more than 0,2 mm in the longitudinal direction when a load of 98 daN is applied to it in that direction. The trolley shall be so constructed that no permanent deformation shall occur in the parts bearing the anchorages during the test. The tolerance on the position of the anchorage points is such that each anchorage point shall be situated at most at 50 mm from corresponding points A, B and K indicated in Figure 1, or A1, B1 and K, as the case may be. If a fourth anchorage is necessary in order to attach the retractor, this anchorage: shall be located in the vertical longitudinal plane passing through K, shall enable the retractor to be tilted to the angle prescribed by the manufacturer, shall be located on the arc of a circle with centre K and with radius KB1 = 790 mm if the length between the upper strap guide and the strap outlet at the retractor is not less than 540 mm or, in all other cases, on the arc of a circle with centre K and radius 350 mm.
3.1.	In the case of a belt equipped with a belt adjustment device for height as defined in 1.8.6 of this Directive, this shall be secured either to a rigid frame, or to a part of the vehicle on which it is normally mounted which shall be securely fixed on the test trolley.
4.	STOPPING DEVICE This device consists of two identical absorbers mounted in parallel, except in the case of restraint systems when four absorbers shall be used for a nominal mass of 800 kg. If necessary, an additional absorber shall be used for each 200 kg increase of nominal mass. Each absorber comprises: an outer casing formed from a steel tube, a polyurethane energy-absorber tube, a polished-steel olive-shaped knob penetrating into the absorber, a shaft and an impact plate. The dimensions of the various parts of this energy absorber are shown in Figures 2, 3 and 4. The characteristic values of the energy-absorbing material are given below. Immediately before each test, the tubes must be conditioned at a temperature of between 15 and 25  o C for at least 12 hours without being used. The temperature of the stopping device during the dynamic testing of safety belts and restraint systems must be the same as during the calibration test to within ± 2  o C. The requirements relating to the stopping device are set out in Annex IX. Any other device giving equivalent results is acceptable.

CHARACTERISTIC VALUES OF THE ENERGY-ABSORBING MATERIAL

(ASTM method D 735 unless otherwise stated)

Shore hardness A:		95 ± 2 at 20 ± 5  o C
Breaking strength:		R o ≥ 343 daN/cm 2
Minimum elongation:		A o ≥ 400 %
Modulus:		at 100 % elongation: ≥ 108 daN/cm 2
		at 300 % elongation: ≥ 235 daN/cm 2
Low-temperature brittleness (ASTM method D 736):		five hours at -55  o C
Compression set (method B):		22 hours at 70  o C ≤ 45 %
Density at 25  o C		1,05 to 1,10
Ageing in air (ASTM method D 573):
70 hours at 100  o C	— shore hardness A:	maximum variation ± 3
	— breaking strength:	decrease < 10 % of R o
	— elongation:	decrease < 10 % of A o
	— mass:	decrease < 1 %
Immersion in oil (ASTM method No 1 Oil):
70 hours at 100  o C	— shore hardness A:	maximum variation ± 4
	— breaking strength:	decrease < 15 % of R o
	— elongation:	decrease < 10 % of A o
	— volume:	swelling < 5 %
Immersion in oil (ASTM method No 3 Oil):
70 hours at 100  o C	— breaking strength:	decrease < 15 % of R o
	— elongation:	decrease < 15 % of A o
	— volume:	swelling < 20 %
Immersion in distilled water:
one week at 70  o C	— breaking strength:	decrease < 35 % of R o
	— elongation:	increase: < 20 % of A o]