EP0659361A2

EP0659361A2 - Seat belt buckle with three branches

Info

Publication number: EP0659361A2
Application number: EP94120078A
Authority: EP
Inventors: Guido Ferrarese
Original assignee: ROFIN Srl
Current assignee: ROFIN Srl
Priority date: 1993-12-22
Filing date: 1994-12-19
Publication date: 1995-06-28
Also published as: ITTO930276V0; ITTO930276U1; EP0659361A3; IT231546Y1

Abstract

The buckle according to the invention comprises, in a shell (11), a carriage (15) slidable in a box-shaped casing (14) between a rest position and an operating position; opposing means (16) movable with respect to the said carriage (15) and opposing the simultaneous insertion into the casing (14) of two tongues (12) connected to corresponding portions of the seat belt, but not opposing the insertion of one tongue (12) only; a spring bolt (17), kept in the rest position by the said carriage (15), a catch lever (17.4) connected to the said bolt (17) to keep a release button (18) depressed in a corresponding aperture of the shell (11), when the bolt (17) is in the rest position, so that the released condition of the buckle is indicated visually to the user.

The two tongues (12) inserted simultaneously into the casing (14) engage the opposing means (16) and cause the carriage (15) to move, thus releasing the bolt (17) which locks the tongues. This does not happen when only one tongue (12) is inserted.

Description

This invention relates to a seat belt buckle with three branches, for example for a safety seat for children carried in cars.
Seat belt buckles with three branches of the type specified above are known.
One known buckle is fixed to one end of one branch of a seat belt which is made to pass between the legs of a child who is carried in a car and seated in a safety seat.
The other two branches of the seat belt are disposed in the form of braces on the body of the seated child and each of them carries, fixed to its free end, a rigid tongue, made for example of metal, which is selectively inserted into and fixed in the buckle to form a substantially Y-shaped set of straps capable of securing the body of the child carried in the car with respect to the seat.
The branches of the belt are made to open by unlocking the tongues from the buckle by means of a push button provided in the buckle.
However, in known buckles of the specified type it is impossible to determine with certainty the safe condition in which the tongues are securely locked in the buckle.
Moreover, the known buckles are complicated and frequently unreliable.
The principal object of the present invention is to provide a seat belt buckle with three branches, for example for a safety seat for children carried in cars, which can be used to secure a child carried in a car with respect to the seat in a rapid and certain way, while also making the safe condition visible when it is present.
A further object is to provide a seat belt buckle as indicated which has a simplified structure, operates in a certain and reliable way and is relatively inexpensive.
To attain these objects, the present invention provides a seat belt buckle with three branches, for example for a safety seat for children carried in cars, whose essential characteristic forms the subject of the principal claim which shall be understood to be provided as an integral part of this document.
Further advantageous characteristics are described in the dependent claims which shall also be understood to be provided as an integral part of this document.
The present invention will be described in detail in the following text with reference to the attached drawings, provided solely by way of example and without restriction, in which:

Fig. 1 is an elevation of the seat belt buckle with three branches, for example for a safety seat for children carried in cars, according to the present invention, in which two branches of the seat belt, to be disposed in the form of braces and provided with corresponding end fixing tongues, are illustrated as separate from the buckle, while all three branches of the seat belt are represented partially and in broken lines for the sake of clarity;
Fig. 2 is a sectional view of the buckle only, through the line II-II in Fig. 1;
Figures 3 and 4 are sectional views through the lines III-III and IV-IV in Fig. 2 respectively ;
Fig. 5 is a sectional view through the line V-V in Fig. 4;
Fig. 6 is a sectional view through the line VI-VI in Fig. 1;
Fig. 7 is a view similar to that in Fig. 4, but in which the fixing tongues of the seat belt branches in the form of braces are correctly inserted into and locked in the belt buckle (the belt branches are omitted for the sake of simplicity);
Fig. 8 is a sectional view through the line VIII-VIII in Fig. 7;
Fig. 9 is a sectional view through the line IX-IX in Fig. 8;
Fig. 10 is a view similar to that in Fig. 7, but showing the buckle not providing any lock action, in a case in which one fixing tongue of one of the braces branches of a belt is inserted independently of the tongue of the other branch;
Fig. 11 is a view similar to that in Fig. 4, but showing a variant embodiment of the belt buckle according to the present invention;
Fig. 12 is a sectional view through the line XII-XII in Fig. 11; and
Fig. 13 shows the buckle shown in Fig. 11, in the same operating condition as the buckle shown in Fig. 10.

With reference, initially, to Figures 1 to 10, the number 10 (Fig. 1) indicates as a whole the seat belt buckle with three branches, for example for a safety seat for children carried in cars, according to an example of an embodiment of the present invention.
The said buckle 10 is used to connect together three branches, R1, R2, R3 of a seat belt of a safety seat (not illustrated) for a child carried in a car, to form a substantially Y-shaped harness to hold the child in the seat.
The said buckle 10 comprises a shell 11 of plastic material, for example heat-resistant ABS, formed by the permanent joining of two half-shells 11.1, 11.2, which together form a void 11.3.
The said shell 11 is fixed by means of a slot 11.4 to one end of the branch R1 of the seat belt (Fig. 1).
Each of the other two branches R2, R3 of the belt carries at its free end a fixed rigid metal fixing tongue 12. Each of the said tongues 12 has a straight portion 12.1 with a locking notch 12.2 and a loop 12.3 for connection to the corresponding branch R2, R3 of the belt. The said loop 12.3 has a plastic coating (Fig. 6), of heat-resistant ABS for example, which provides, next to part of the corresponding portion 12.1, a guide projection 12.4 (see also Fig. 10), complementary to the guide projection 12.4 provided on the loop of the other tongue 12. By this arrangement, the two tongues 12 may be correctly placed adjacent to each other before insertion into the buckle 10, with the corresponding portions 12.1 brought together and parallel with each other and the locking notches 12.2 opposite each other, to facilitate the correct and secure operation of insertion into and locking in the buckle 10, as will be made clearer in the following text.
For this purpose, two adjacent slots 11.5 (Fig. 4) are provided in the shell 11, opening on the surface opposite the branch R1 integral with the shell and communicating with the void 11.3; each slot can permit the free passage of a corresponding straight portion 12.1 of a tongue 12. In the inner void 11.3 of the shell 11 there is provided a spring locking mechanism, indicated as a whole by the number 13 (Fig. 2) and comprising:

A box-shaped casing 14, fixed in the said shell 11 (by securing pins integral with the shell and corresponding holes in the said box-shaped body, see for example Fig. 5) and comprising a pair of metal plates 14.1, 14.2, forming the bottom and the top of the said casing 14 respectively and assembled with a space between them by means of spacing side pieces 14.1 extending from the bottom 14.1 along part of its length. The said box-shaped casing 14 has, on its front face, a pair of slots 14.3, corresponding and near to the slots 11.5 of the shell 11. Corresponding slotted holes 14.4, 14.5 (Fig. 3) are provided in the bottom plate 14.1 and in the top plate 14.2 of the box-shaped casing 14, and are aligned with each other in a plane substantially orthogonal to the said plates and near the slots 14.3, while corresponding pairs of guide holes 14.6, 14.7 are provided on each side of each of the said slots 14.4, 14.5 (Fig. 3), in the same plane orthogonal to the said plates.
A flat carriage 15, housed slidably in the said box-shaped casing 14, so that it can slide along the plates 14.1, 14.2, and guided by the sides 14.1' between a forward rest position in which its front edge 15.1 faces and is adjacent to the said slots 14.3 of the casing 14 (Fig. 4) and a rearward operating position remote from the said slots. The said carriage 15 is normally kept in its said rest position by means of a compression coil spring 15.2 interposed between the carriage and a projection of the bottom plate 14.1 opposite the slots 14.3.
Opposing means 16, supported movably on the said carriage 15 and consisting of a strip 16.1 substantially in the form of half a circular ring with each free end facing one of the said slots 14.3 and on the same level as the slots. The said strip 16.1 has, on its face resting on the carriage 15, a projection in the form of an engaging peg 16.2, extending from its median part and held in a corresponding guide slot in the form of an arc of a circle 15.3 (Fig. 4), provided in an area of the said carriage 15 remote from the said front edge 15.1, in such a way that limited rotary movements of the strip 16.1 are permitted about an axis orthogonal to the carriage 15 and passing through the centre of the strip. (The branches of the said slot 15.3 extend in mirror symmetry on opposite sides of the median vertical longitudinal plane of the carriage 15, which is also the plane of mirror symmetry of the slots 14.3 and 11.5). Raised edges at 15.4, partly in the form of an arc (Fig. 4), guide the strip 16.1 in the said rotary movements on the carriage 15.
A spring bolt 17 in the form of a three-pronged fork (Fig. 3) whose central prong 17.1 is always inserted in the slot 14.4 of the bottom plate 14.1 of the casing 14, and whose two outer prongs 17.2 are longer and are inserted in the said pairs of guide holes 14.6 and 14.7 of the plates 14.1 and 14.2. Each of the free spaces between the prongs of the bolt 17 corresponds to one of the slots 14.3 of the casing 14. A compression coil spring 17.3 (Figs. 2 and 3) is interposed between the said bolt 17 and the half-shell 11.1, so that the bolt 17 is kept pressed in a direction substantially orthogonal to the carriage 15 and in contact with the upper surface of the carriage (with its intermediate prong 17.1) when the carriage 15 is in its said rest position.
A catch lever 17.4 - substantially V-shaped, and of the first class (with its fulcrum on the bottom plate 14.1) - which has a fork-shaped end 17.5 interposed between the bolt 17 and the bottom plate 14.1 and disposed so that it is raised from the plate 14.1 when the carriage 15 is in the said rest position, while its other end 17.6 is lowered (Fig. 2).
A release button 18, fitted movably and guided - in a direction substantially orthogonal to the carriage 15 - in a corresponding aperture 18.1 (Fig. 2) of the half-shell 11.1, above the said other end 17.6 of the catch lever 17.4, so that it can be depressed in the said aperture, substantially in contact with the lever end 17.6, when the carriage 15 is in its said rest position.

Operation:

In correct operation, the rectilinear portions 12.1 of the tongues 12, joined together as illustrated in Fig. 1, are inserted simultaneously and by equal depths into the corresponding slots 11.5 of the shell 11 and 14.3 of the casing 14, so that each engages frontally a corresponding free end of the opposing means 16. These opposing means maintain a disposition with arms symmetrical with respect to the said plane of symmetry of the carriage 15.
The synchronized and balanced thrust exerted by the tongues 12 on the opposing means 16 is therefore uniformly and directly transmitted to the carriage 15, which is thus caused to carry out its operating movement in a direction parallel to that of the insertion of the said tongues and in opposition to the action of the return spring 15.2, until the said rectilinear portions 12.1 penetrate completely into the shell 11. In this condition (Fig. 7), the carriage 15 no longer opposes the bolt 17, which, being elastically stressed by the spring 17.3, slides in a direction substantially orthogonal to the said carriage, its central prong 17.1 extending to the level of the slot 14.5 of the cover 14.2 and simultaneously engaging the opposing notches 12.2 of the tongues 12, which in this way are securely held to prevent their extraction from the buckle 10. The return of the carriage 15 is then prevented by the central prong 17.1 of the bolt 17 extending into the casing 14.
The sliding of the bolt 17 causes the catch lever 17.4 to oscillate about its fulcrum so that its said other end 17.6 is raised and this in turn raises the button 18, which emerges into the aperture 18.1 (Fig. 8). This indicates to the user that the condition of secure locking of the tongues 12 in the buckle 10 is obtained.
Conversely, by manually pressing the button 18, the bolt 17 is returned, by reverse oscillation of the catch lever 17.4 about its fulcrum, to a retracted position, in opposition to the action of the spring 17.3, thus releasing the carriage 15. The carriage, under the elastic force of the return spring 15.2, is automatically returned to its rest position. Simultaneously, the bolt 17 also releases the tongues 12. The button 18 is depressed in the aperture 18.1 which indicates to the user the condition of release of the buckle 10, in which the tongues 12, being no longer secured, may be withdrawn from the buckle 10.
If, by incorrect operation (Fig. 10), only one tongue 12 is inserted into the buckle 10, with its rectilinear portion 12.1 introduced through one slot 11.5 of the shell 11 and the corresponding slot 14.3 of the casing 14, this tongue presses on the opposing end of the opposing strip 16.1, which is thus forced to pass through an arc of rotation about its axis until its engaging peg 16.2 bears against the end of the slot 15.3 remote from the said tongue 12. The carriage 15 is therefore not made to slide in opposition to the action of the spring 15.2, but remains in its rest position. The bolt 17 is therefore prevented by the said carriage 15 from entering the position in which it locks the tongue 12. The buckle 10 remains inoperative and this condition is made evident to the user by the button 18, which is still depressed in the corresponding aperture 18.1 of the shell 11.
Naturally, the effects of the present model extend to models which provide equal utility, using the same innovative concept. Thus, for example, the opposing means may have a technical configuration different from that described above.
Figures 11 to 13 show a variant embodiment of the buckle according to the present invention, indicated here by the number 20. (In the said figures, similar parts are identified with the same reference numbers as those used in Figures 1 to 10).
In the present example, the opposing means, indicated by 21, consist of a rocker 22 with equal arms, fitted on the carriage 15 by means of an intermediate pin 23 with its axis orthogonal to the carriage and disposed in its said plane of symmetry.
The end of each arm of the rocker 22 is opposite a corresponding slot 14.3 so that the end can be engaged by a portion of the tongue 12.1 when this is inserted into the buckle 10 through the said slot.
Fig. 13 clearly illustrates the inoperative condition of the buckle 20 in the case of insertion of only one securing tongue 12.
Conversely, the operative condition of the buckle 20, with portions 12.1 of the buckles 12 correctly inserted fully as a pair, is similar to that of the buckle 10 illustrated in Fig. 7. In this case, the opposing rocker 22 directly transmits the simultaneous and balanced thrust exerted by the tongues 12 to the carriage 15, which is thus made to complete its operating movement in opposition to the action of the spring 15.2.
The operation of the buckle 20 corresponds exactly to that of the buckle 10, and therefore reference should be made to the explanation of the operation of the buckle 10.

Claims

Seat belt buckle with three branches, in which a spring lock (13) is fixed in a shell (11) provided with at least one aperture (11.5) for the free passage of corresponding portions (12.1) of two rigid fixing tongues (12) of two branches of the seat belt, the said portions of tongues (12.1) having to be correctly placed adjacent and parallel to each other and with their corresponding engagement notches (12.2) opposite each other, and in which the said lock (13) is provided with a box-shaped casing (14), having at least one aperture (14.3) corresponding to the said at least one aperture (11.5) of the shell (11) for the free passage of the said portions (12.1) of the tongues (12), characterized in that the said spring lock (13) comprises:
- a carriage (15) housed in the said box-shaped casing (14) and slidable between a rest position and an operating position, remote from the said at least one aperture (14.3), the said carriage (15) being normally maintained in its said rest position by elastic return means (15.2);

- opposing means (16, 21), supported movably with respect to the said carriage (15) and disposed so that they oppose the insertion through the said box-shaped casing (14) of the said portions (12.1) of the tongues (12), if correctly placed adjacent to each other to form a pair, while the said opposing means (16, 21) do not oppose the insertion of only one of the said portions (12.1) of tongues through the said box-shaped casing (14), yielding to its thrust by a relative movement with respect to the said carriage (15);

- a spring bolt (17), pressed - for example in a direction substantially orthogonal to the said carriage (15) - by elastic means (17.3) and kept retracted, in opposition to the action of the said elastic means (17.3), by the carriage (15) when the carriage is disposed in its said rest position;

- a catch lever (17.4), for example a substantially V-shaped lever, effectively connected to the said bolt (17) so that it has one end (17.6) lowered in the said shell (11) when the said bolt (17) is kept retracted by the said carriage (15) in its said rest position;

- a release button (18) fitted movably and guided - for example in a direction substantially orthogonal to the said carriage (15) - in an aperture (18.1) of the said shell (11) opposite the said end (17.6) of the catch lever (17.4) so that it is depressed in the said aperture, when the said bolt (17) is kept retracted by the said carriage (15) in its said rest position, so that when the said portions (12.1) of the two tongues (12) are inserted simultaneously through the said box-shaped casing (14) and are correctly placed adjacent to each other with the engagement notches (12.2) opposite each other the said opposing means (16) transmit their thrust to the carriage (15) which, by sliding into its said operating position, in opposition to the action of the said elastic return means (15.2), releases the bolt (17) which is elastically forced (by 17.3) to advance, locking the carriage (15) in the operating position, engaging the notches (12.2) of the tongues (12) and making the catch lever (17.4) oscillate so that its said end (17.6) is rotated upwards in the said shell (11), this action raising the button (18) in the said aperture (18.1) of the shell, while by pressing the said raised button (18) and therefore making the said lever (17.4) oscillate in the reverse direction, the bolt (17) is returned, causing it to be retracted in opposition to the elastic means (17.3), so that the carriage (15) is automatically returned to the rest position (by 15.2), and the button (18), remaining depressed in the aperture (18.1), indicates the released condition of the buckle; and so that the said carriage (15) also remains in its rest position when only one portion (12.1) of a tongue (12) is inserted, since the thrust of this portion causes a relative movement of the opposing means (16, 21) with respect to the carriage (15), without the sliding of the carriage into its said operating position.
Buckle according to Claim 1, characterized in that the said opposing means (16) comprise a strip (16.1) substantially in the form of half a circular ring with its free ends facing the said at least one aperture (14.3), this strip being fitted on the carriage (15) so that it can rotate at least partially about an axis substantially orthogonal to the carriage (15) and passing through the centre of the strip, each end of the said strip (16.1) being capable of being engaged by one of the said portions (12.1) of the tongues (12) during insertion into the said casing (14).
Buckle according to Claim 1, characterized in that the said opposing means (21) comprise a rocker (22), fitted so that it can oscillate on the carriage (15) by means of an intermediate pin (23) with its axis substantially orthogonal to the carriage, each end of the said rocker (22) being capable of being engaged by one of the said portions (12.1) of the tongues (12) during insertion into the said casing (14).