US3177545A

US3177545A - Buckle for a safety belt

Info

Publication number: US3177545A
Application number: US184775A
Authority: US
Inventors: Svensson Rolf Henrik
Original assignee: Individual
Current assignee: Individual
Priority date: 1961-04-17
Filing date: 1962-04-03
Publication date: 1965-04-13
Anticipated expiration: 1982-04-13
Also published as: GB939112A; CH404265A; DE1853019U; SE301592B; BE616441A; DK108220C

Description

A ril 13, 1965 R. H. SVENSSON 3,177,545

v BUCKLE FOR A SAFETY BELT Filed April 3, 1962 2 Sheets-Sheet 1 INVENTOR $1 Han n'!( .J ve n Json April 13, 1965 R. H. SVENSSON 3,177,545

BUCKLE FOR A SAFETY BELT Filed April 3, 1962 2 Sheets-Sheet 2 INVENTOR 10H l/um'x Jrcnssan ORNEY United States Patent 3,177,545 BUCKLE FOR A SAFETY BELT Rolf Henrik Svensson, 1 Viktoriagatan, Halmstad, Sweden Filed Apr. 3, 1962, Scr. No. 184,775 Claims priority, applicagtgznsslweden, Apr. 17, 1961,

3 1 Claim. (Cl. 24-170) This invention relates to buckles for safety belts and similar strap members.

More particularly this invention relates to safety belt buckles and the like elements having a base portion for securing one belt-part, a flap actuated by a spring member and an internal locking member actuated by a second spring member, said locking member having a portion, suitably knurled or serrated, for clamping against the other belt-part, said locking member further being adapted, upon-release, to be pivoted out of its locking position by the flap.

Buckle constructions known in the prior art have generally the drawback that the flap, in order to provide satisfactory locking of the other belt-part, will project with its free end from the base portion or from the two superposed belt-parts, with the result that the flap becomes a protrusion and may be opened accidentally.

One main object of the present invention is to eliminate said inconvenience so that the free end of the flap conforms to the belt-parts.

Further objects and advantages of the invention will become apparent from the following description, considered in connection with the accompanying drawings which form part of this specification and of which:

FIG. 1 is a sectional view along line II of FIG. 3 of a buckle constructed in accordance with the invention.

FIG. 2 is a perspective view of the buckle shown in FIG. 1 and with some portions of the buckle and the belt assumed removed for clarity. FIG. 3 is a plan view of the buckle shown in FIGS. 1 and 2.

FIG. 4 is a sectional view along line IVIV of FIG. 5 of another embodiment of a buckle according to the invention. FIG. 5 is a plan view of this buckle.

FIG. 6 is a perspective view of the buckle shown in FIGS. 4 and 5. In order to obtain improved clarity, some parts are supposed removed in FIGS. 5 and 6.

In both embodiments illustrated by FIGS. 1 to 3 and 4 to 6, respectively, certain of the same reference numerals have been employed to denote equivalent parts; some of the numerals and others of the numerals followed by primes denoting parts of forms difliering from the forms of certain corresponding parts denoted by unprimed reference numerals.

Referring to he drawings and in particular FIGS. 1 to 3 a base portion of the buckle is denoted generally by It) and has a substantially U-shaped cross section with marginal flanges 12. The base portion may be made of sheet plate and has a cross-slit 14 through which the end portion 18 of one belt-part 16 is threaded to then be looped and united with the underlaying portion of the belt. The marginal flanges 12 are provided with apertures for a cross-pin or shaft 20 secured against rotation in relation to the base portion 10, for instance, by the pin having a hexagonal head 22 entering into a complementary recess in one marginal flange 12. Pivotally mounted on the pin 20 is a flap 24 which likewise may be made of sheet plate, said flap having marginal flanges 26 through which the pin 20 passes. A spring member 28 is disposed around pin 20 and has one end secured to said pin and extending at its opposite end through a hole 29 in the flap 24. The

spring member 28 urges the bent handle end 34 of the flap 24 counter-clockwise, as viewed in FIG. 1, against the base portion 10.

A locking member 32 is rotatably mounted inside the flap 24 on the same pin 20 as the flap; said locking member is, however, capable of performing a limited angular movement in relation to the flap. The locking member is actuated by a spring member 34, the end portions of which are rigidly secured to the locking member and the pin 20, respectively. The locking member is provided with a knurled or serrated portion 36 for clamping the other belt-part 38 against the base portion 10, which may have for this purpose a backing section in the form of a protuberance 40.

The locking member 32 has a recess 42 through which the spring member 34 is inserted at the assembly before the pin 20 is pushed through the locking member. The pin may have a longitudinal groove 44 for receiving the one end portions of the two

spring members

28 and 34. The recess 42 may be closed afterwards. The spring member 34 tends to rotate the locking member 32 in the same direction as the flap 24, the freedom of movement of the locking member being limited, however, by a shoulder 46. Either one or both spring members may be pre-tensioned. Inside the flap the locking member 32 is extended into a tongue 48 or similar prolongation which serves for preventing the locking member from accidental rotating in relationship to the flap 24, as will be explained in greater detail below.

The buckle is primarily intended for use with safety belts for seats in vehicles, such as airplanes and cars, and it operates in the following way.

When the flap 24 is put up so that its handle-end 3i 1 leaves the base portion 10, the locking member 32 after some angular movement of the flap is brought along by virtue of the shoulder 46 on said member. Both

spring members

28, 34 are then cocked. At the same time the locking membr 32 has withdrawn so far from the protuberance 40 of the base portion that the belt-part 38 may be introduced between the two elements. After a proper tightening of this belt-part the flap 24 is released, whereupon it returns to a position in which its handle-end 3t bears against the two superposed belt-parts. The locking member 32 does not accompany the flap throughout its entire angular movement but stops earlier so as to bring about the proper locking effect against the beltpart 38. In other words, the flap 24 moves slightly further in a counterclockwise direction as viewed in FIG. 1 relative to the tongue portion 48 of the locking member. The angular displacement required in order that the beltpart 38 be retained in its tightened position is thus imparted to the locking member 32 and not to the flap 24.

It will readily be understood that the locking member 32 cannot (the shoulder 46 being disregarded) rotate counter-clockwise, as viewed in FIG. 1, in relation to the flap 24 further than to a position wherein the tongue 48 clamps the belt-part 38 against the lower portion 1% This limitation of the freedom of movement has for its object to prevent failure of the locking member in cases of catastrophy and the like, when the safety belt is subjected to a very large, more or less momentary load. The stress on the buckle would then be so large that the flap 24 could give and release the shoulder 46 of the locking member so that the member could rotate counterclockwise in relation to the flap, as viewed in FIG. 1. However, the tongue 48 limits this rotation so as to ensure that the knurled portion 36 would still be effective, at least partially, to maintain the belt-part 38 locked.

In the embodiment shown in FIGS. 4 to 6 the locking I member 32' has a knurled portion 36', and a tongue portion 48 for limiting the clockwise rotation of member 32' as shown in FIG. 4. Member 32' is formed with a central recss 50 housing a spring member generally denoted by 52 and drawn around the pin or shaft 20. This spring a spring memb'erare pre-tensioned;

1 The pin'20 is kept locked relative the-'basepart 10 by manner as in the embodiment shown in'the FIGS. 1' to 3" the pin 20 has a longitudinal groove '44' into which a por tion 60 (FIG; 4) of the springmemb'erjSZ is introduced and therewith immobilized relative said pin. Between said portion 60 and the end portion 58 the spring member is disposed in agroup of windingsfilaround the'shaft-actu ating the locking member 32" and is thus-tensionedwhen said locking member is moved upwards. Another group 64 of windings of the spring member'formed between the j end portion 5 4 and the portion 60 is adapted tolactuate the flap 24.- Preferably both groups of windings of the means of alpi'n 66. In the axial direction the shaft is blocked by means of retaining rings 68; While several more or less specific embodiments of and the locking the invention havebeen shown and described,'itisto. be

understood that this is for purpose" of illustration only; and that the invention is not to be limited thereby, but;

its scope is to be determined by the appendedxcla-im. What I claim-is: a V A safety belt buckle comprising V: (a) a base to which one end of a belt'is adapted to be secured, a j (b) a flap mounted at one end on sai'd'base to pivot between an open anda closed position, respectively,- (c) a first spring uprging said flap to its closed position,

(d) a locking member mounted within said flap be-' tween said flap and said base for'oscillation about the pivotalaxis of said flap between a locking posi-- tion and a released position, respectively,

formed to clamp the other end of a belt against said v base, when said member is'in' itslocking position, I '(f) 'a second spring urging said locking member towards its locking position independently .of said first spring and of said flap but in the same direction as the first-named spring urges said flap, and (g) a shoulder-formed on said lockingmember and projecting through'a slot in said' fla'p to beengag'ed by said 'flaptci pivot said locking'member from its locking position to its'released'positiofij whens'aid flap is moved from its closedl'to its open position, (h) said slot extending about said pivotal axis a distance sufiicient to'disengagesaid shoulderupon'movement of said locking member and said flap, under .the:

action of said springs, to saidilocking positionand'to said closed position, respectively, whereby said flap must move independently of said locking" member towardttheopen position of saidflap before movingsaid lockingmember' toward released position, and:

References Cited in the tile of this patent I UNITED STATES PATENTS:

2,517,424" Griswold-;. Aug. 1,1950" 7 2,867,876 Elsner et a1. Jan. 13, 1959 2,869,200 Phillips et a1. Jan. 20,1959. 2,916,786 Legat Dec; 15, 1959' 2,965,942" Carter V-V Dec. 27,1960 1 Y OTHER-REFERENCES" V a 1,204,470 7 'France W Aug-10," i959