GB1592259A

GB1592259A - Safety belt buckle

Info

Publication number: GB1592259A
Application number: GB5200577A
Authority: GB
Original assignee: Francaise du Ferodo SA
Current assignee: Valeo SE
Priority date: 1977-12-14
Filing date: 1977-12-14
Publication date: 1981-07-01

Description

(54) SAFETY BELT BUCKLE (71) We, SOCIETE ANONYME FRANCAISE DU FERODO, of 64 avenue de la Grande-Armée, 75017 Paris, France, a French Body Corporate, do hereby declare the invention, for which we pray that a patent may be granted to us, and the manner in which it is to be performed, to be particularly described in and by the following statement: The invention relates to a safety belt buckle especially for a safety belt for an occupant of a vehicle.

It is known that a safety belt comprises a strap intended to pass round a part of the body of the occupant, the opening and closing of the belt being effected with the aid of a buckle adapted to introduce a discontinuity into the strap on opening.

A safety belt buckle is already known comprising a buckle body and a keeper which is less wide than the first and is adapted to enter the buckle body in which it is automatically locked by being engaged by the noses of two identical pivoted latch bolts under the action of a spring. Opening of the buckle is effected by a push member which is mounted in the buckle body and acts to separate the latch bolts to disengage them from the keeper.

When a safety belt of a land vehicle, especially a road vehicle, is equipped with a buckle of this type, it is important that it should satisfy strict conditions of resistance to major forces which can be exerted in the case of accident, without its operational capacity being reduced, and in particular without any inconvenience or difficulty resulting in opening the buckle which operation must be easy under all circumstances.

It is one purpose of the invention to provide a safety belt buckle which fulfils the conditions stated above, and which comprises a small number of component parts and so is both simple and economical to assemble.

In the following description and claims, the term "latch" will be used for a latch bolt.

A safety belt buckle according to the invention comprises a buckle body and a keeper which enters the body, -a pair of pivoted latches to engage notches in opposite edges of the keeper thereby to retain the keeper within the body, there being spring means to urge the latches towards one another into the keeper-engaging position, and a push button slidable within the body in the direction of keeper entry into the body, the push button on such sliding in the direction of entry directly engaging the latches to separate them to release the keeper.

In a convenient form of the buckle, each latch has a head, a tail and a notch-engaging nose between the head and tail, and is pivoted at its tail farther from the keeper entry than the head, and wherein the push button engages the heads to release the keeper.

In one such form of buckle, the push button has features which engage ramps on the latch heads, which ramps are inclined to the direction of sliding of the push button in relation to the buckle body, i.e. in the direction of entry of the keeper into the buckle body.

The push button may comprise two parallel walls joined by small bridge pieces whereof the faces most remote from an actuating bar fast with one of the walls carry rods, pins or studs constituting the rampengaging features, the rods, pins, pegs or the like being advantageously metallic and the remainder of the push button being advantageously of a plastics material.

In another form of such buckle the push button has ramps inclined in the direction of sliding of the push button, which ramps are engaged by studs projecting perpendicularly from the latch heads.

According to a feature of the invention, the buckle may also comprise stop means to prevent pivoting of the latches in the direction tending to free the keeper when the push button is in a position corresponding to that of closure of the said buckle.

Some forms of safety belt buckle of this invention are described in the following by way of example and shown in the accompanying drawings, in which: Figure 1 is a view, partly in elevation and partly in section, of one form of safety belt buckle, Figure 2 is a view analogous with that in Figure 1, with parts having been removed for clarity, Figure 2A is a partial sectional view along the line 2A - 2A in Figure 1, Figure 2B is a view analogous with that in Figure 2, but for a variant of embodiment, Figure 3 is a sectional view along the line 3 - 3 in Figure 1, Figure 4 is a view, in the direction of the arrow A in Figure 3, of the push button of the buckle of Figures 1 to 3.

Figure 5 is a sectional view along the line 5 - 5 in Figure 4, Figure 6 is a sectional view along the line 6 - 6 in Figure 5, Figure 7 is a view, partly in elevation and partly in section, o a second form of a buckle Figure 8 is a view analogous with that in Figure 2, but for the buckle of Figure 7, Figure 9 is a sectional view along the line 9 - 9 in Figure 7, Figure 10 is a view analogous with that in Figure 7, but for another condition of the buckle, Figure 11 is a view in the direction of the arrow B in Figure 9 of the push button of the buckle as shown in Figures 7 to 10, Figure 12 is a sectional view along the line 12 - 12 in Figure 11, Figure 13 is a sectional view along the line 13 - 13 in Figure 12, Figures 14, 15, 16 and 17 are views analogous respectively with those in Figures 8, 10, 12 and 13, but for a variant of embodiment of the belt buckle as represented in Figures 7 to 13.

Reference is made firstly to Figures 1 to 6.

In the form of embodiment as illustrated in these Figures, the safety belt buckle according to the invention comprises a first element or buckle body 10 and a second element 11 constituted by a keeper 12 the head 13 of which forms two stop faces 14 and 15 adjacent to a bridge piece 16 connecting the head 13 to the tail of the keeper, which is generally continued by a ring (not shown) which receives the strap of a safety belt for the equipment of which the buckle is intended.

The noses 67 and 68 of two identical latches 20 and 21 are adapted to co-operate, when the buckle is in the closure condition as shown in Figure 2, with the stop faces 14 and 15 of the keeper 12. The latch 20, whose nose 67 is situated between its head 37 and its tail 22, is mounted for pivoting by the said tail about a pivot 24, while the latch 21, whose nose 68 is situated between its head 38 and its tail 23, is mounted for pivoting by its tail 23 about a pivot 25.

As may be seen clearly from Figure 2A, each of the pivots 24, 25 is constituted by a cylindrical stay block 26 carrying on its front faces 65 and 66 pivot pins 27 and 28 which pass through two parallel plates 29 and 30 and terminate in widened portions 31 and 32 formed in situ after assembly. In the course of the latter the plates 29 and 30 are brought and maintained in contact with the faces 65 and 66 with the result of a precise calibration of the spacing of the plates 29 and 30.

This spacing, slightly greater than the thickness of the latches 20 and 21, ensures a satisfactory pivoting of the latches without friction or jamming.

Between the plates 29 and 30. the spacing of which is likewise slightly greater than the thickness of the keeper 12, a leaf spring 33 of U-form is lodged, the ends 34 and 35 of which bear upon the latches 20 and 21 to thrust them towards one another, also a helical spring 36 disposed between the tails 22 and 23 of the latches and held in position by the fact that it is of a diameter slightly greater than the width of two slots 17 and 18 formed in the plates 29 and 30 respectively; the spring 36, placed under stress when the keeper 12 is introduced into the buckle body 10, causes the ejection of the said keeper from the buckle body as soon as the heads 37 and 38 of the latches 20 and 21 respectively are sufficiently far from one another in the pivoting of the said latches about the pivots 24 and 25, against the action of the spring 33.

In order to cause this pivoting movement, in this embodiment of the invention provides a frontal push button 40, Figures 3 to 6, shaped with two parallel walls 41 and 42 with spacing very slightly greater than the thickness of the assembly formed by the plates 29, 30 enclosing the latches 20 and 21 between them. The walls 41 and 42 are united by small bridge pieces 43 and 44 whose faces 45 and 46 which are more distant from a presser bar 47 prolonging the wall 41 carry cylindrical rods or pins 48 and 49, which are advantageously of metal while the remainder of the push button is of a plastic material.The rods or pins, 48, 49 are placed, with the small bridge pieces with which they are fast, in parallel slots 50 and 51 of the plates 29 and 30, which slots open on the forward edges 52 and 53 of the said plates and are situated in line with the heads 37 and 38 of the latches in the closed condition of the buckle, more precisely opposite to the ramps 62 and 63 formed on the forward edges of the said heads. In form of embodiment as described and represented with each bridge piece 43 and 44 there is associated an appendage, as 54 for the bridge piece 44, which, extending parallel with the walls 41 and 42, contributes to the guidance of the push button 40 in relation to the plates 29 and 30, to which the walls 41 and 42 are adjacent and parallel.

The plates 29, 30, the latches 20, 21 and the elements which are associated with them, of the buckle body 10, are enclosed in a casing 55 the front face of which is closed by an end piece 56 forming an aperture 57 for introduction of the keeper 12 into the said buckle body. The end piece 56, the cross-section of which matches that of a step 58 formed by the bar 47 of the push button 40 with the walls 41 and 42 of the said button, has grooves 59 of a design matching that of the edges 52 and 53 of the plates 29 and 30 which they bestride.The casing 55, with which the end piece 56 is made fast by ratchet-type engagement or by means of screws such as that shown at 64, Figure 3, provides passage at its posterior extremity for a member 60 for connection with a strand of the safety belt, the said member 60 being made fast with the plates 29 and 30, between which it is partially lodged, by a rivet 61 or the like.

The operation of the safety belt is as follows: The closed condition of the buckle is shown Figures 2 and 3. The keeper 12 is within the casing 55 and the noses 67 and 68 of the heads 37 and 38 of the latches thrust by the spring 33 are in contact with the stop faces 14 and 15 of the keeper, preventing extraction of the latter and therefore opening of the buckle, even under very great forces tending to separate the keeper from the body of the buckle.

If, starting from this condition, one presses upon the push button 40 in the direction of the arrow A in Figure 3, the rods or pins 48, 49 move in the slots 50 and 51 of the plates 29, 30, co-operating with the ramps 62 and 63 of the heads 37 and 38 of the latches 20 and 21 respectively. The translational movement of the push button 40 causes pivoting of the latches 20 and 21 about the pivots 24 and 25 against the action of the spring 33, in the directions of the arrows f and p and, when the heads 37 and 38 of the latches are sufficiently distant from one another, the keeper 12 is pushed back out of the buckle body 10 by the helical spring 36 which was previously stressed.

The form of the ramps 62 and 63 is advantageously as shown in Figure 2, that is to say with a slope which increases progressively and in an evolutive manner from the noses 67, 68 towards the free extremities of the said heads, so that, as frequently required, a large movement of the push button at first causes only a slight lateral displacement of the latches.

On relaxation of the pressure upon the push button 40 the spring 33 returns the latches towards one another and in doing so returns the push button into its initial position.

In order to close the buckle the keeper 12 is introduced into the buckle body 10, pushing back the heads 37, 38 of the latches against the action of the spring 33. After the latches have been pushed aside, they are returned by the spring 33 into the condition for locking the keeper, which at the same time places and keeps the helical spring 36 under compression.

The form of embodiment as represented in Figure 2B is distinguished from that shown in Figures 1 to 6 by the fact that the rods 48a and 49a of the push button are guided in ports 130 and 131 provided in the latches 20a and 21a respectively. The port 130 has longitudinal edges 62a and 132; likewise the port 131 comprises longitudinal edges 63a and 133.

The longitudinal edges 62a and 63a correspond respectively to the ramps 62 and 63 of the latches 20 and 21 of the form of embodiment as shown in Figure 2. However the said ports carry out the supplementary function of diminishing the risks of undesired opening of the safety belt buckle when a pull is exerted upon the keeper 12a in the direction of the arrow F1. In fact, if such a pull had the effect of tending to cause the latches 20a and 21a to rotate in the directions of the arrows fi and f '1, that is to say in the direction tending to separate these latches from the keeper 12a and thus to cause opening of the buckle, the said latches would be retained in the closed position (represented in Figure 2B) by the cooperation between the rods 48a and 49a with the internal. longitudinal edges 132 and 133 of the ports 130 and 131.

The edges 62a and 63a of the ports - like ramps 62 and 63' (Figure 2) - have such a form that the commencement of the pushing in of the push button 40a causes practically no rotation of the latches 20a and 21a, this rotation being effected only at the end of the push-in stroke of the said push button. To this end, in the example, the part of each of these ports which is most remote from the rotation axis 24a(or 25a) of the corresponding latch 20a (or 21a) extends substantially parallel with the axis of symmetry 140 of the buckle.In this way, when a pull is exerted upon the keeper 12a in the direction of the arrow F1, if this pull causes forces F2 and F3 upon the latches 20a and 21a tending to separate them from the axis 140, the parts 132a and 133a of the edges 132 and 133 which are parallel with the axis 140 will exert upon the rods 48a and 49a forces F2 and F3 having directions perpendicular to the axis 140, without any component in a direction contrary to that of the arrow F1.

Apart from what has been described above, the operation of the safety belt buckle as shown in Figure 2B is identical with that of the buckle as shown in Figures 1 to 6.

Reference will now be made to Figures 7 to 13, which relate to another form of embodiment.

In this form, the keeper 70 is of construction analogous with that of the keeper 12 of the previous form of embodiment, and the same applies to the buckle body 71 which comprises two plates 72 and 73 with spacing slightly greater than the thickness of two latches 74 and 75 mounted for pivoting by their tails 76 and 77 respectively about spindles 78 and 79 passing through the said plates. As in the above-described form of embodiment, the keeper 70 is adapted to be immobilised by the noses 69a and 69b disposed between the heads 80, 81 and the tails 76, 77 respectively of the latches 74 and 75, the said heads and consequently the said noses being thrust towards one another by a U-shaped leaf spring 82. A helical spring 83 for ejection of the keeper 70 is provided between the latches and is held in place in slots 120 and 121 of the plates 72 and 73.

The latter, with the latches 74, 75 and the springs 82, 83, are enclosed in a casing 84 the front face of which is closed by an end piece 85 with opening 86 for introduction of the keeper, the casing also enclosing a part of a member 87 for connection of the buckle body with the strap of a belt, the extremity 88 of which member, lodged between the plates 72 and 73, is connected to the said plates by a stud 89, a rivet or the like, In this form of embodiment however the plates 72 and 73 are not equipped with longitudinal slots as in the. embodiment of Figures 1 to 6, but have apertures 92 and 93 (Figure 8) in the vicinity of their front edges 90 and 91, which apertures are inclined in the longitudinal direction of introduction of the keeper 70 into the buckle body and are provided to clear passage for studs 94 and 95 fast with the heads 80 and 81 of the latches 74, 75, through which they extend from side to side.

The said studs, by which the pivoting movement of the latches is controlled, are adapted to be actuated by a frontal push button 100 mounted for sliding in the direction of the arrow B, Figures 9 to 13, and shaped according to a sheath of rectangular cross-section limited by walls 101, 102, 103 and 104. The walls 102 and 104 possess bosses 105, 106 and 107, 108 respectively, on which there are formed ramps like that shown at 109 for the boss 105 or at 110 for the boss 106, the said ramps advantageously having an evolutive form the slope of which increases progressively from their posterior extremities, so that a relatively great displacement by pressing of the push button at first causes only a slight lateral displacement of the studs 94 and 95 with which the said ramps co-operate, and consequently a slight pivoting of the latches.For its translational guidance the opposite walls 101 and 103 of the push button co-operate with the longitudinal edges 111 of the plates 72 and 73, while skids 112, 113, 114 and 115 on the internal faces of the bosses 105 - 108 slidingly co-operate with the surfaces of the said plates.

The operation of this form of embodiment, as regards the closure of the buckle, is entirely analogous with that of the form of embodiment described with reference to Figures 1 to 6.

When the keeper 70 and the buckle body 71 are in the condition as shown in Figures 8 and 9, the noses 69a, 69b of the heads 80 and 81 of the latches thrust by the spring 82 are in contact with the stop faces of the keeper, and the buckle is closed.

For its opening, the push button 100 is pressed in the direction of the arrow B and the displacement of the ramps 109 and 110 through the intermediary of the studs 94, 95 - causes the pivoting of the latches 74 and 75 in the directions of the arrows f and r against the action of the spring 82. When the heads 80 and 81 of the latches are sufficiently remote from one another, the keeper 70 is ejected from the buckle body 71 by the helical spring 83, and then the condition of the buckle is that shown in Figure 10, from which, as soon as the pressureS upon the push button 100 is relaxed, the spring 82 returns the latches 74, 75 towards one another and in doing so causes the return movement of the push button into its initial position by co-operation of the studs 94, 95 with the ramps 109 and 110.

The buckle as represented in Figure 14 to 17 is distinguished from that shown in Figures 7 to 13 by features having the purpose (like the ports 130 and 131 of the latches of the buckle as shown in Figure 2B) of preventing an undesired opening of the buckle when a pull is exerted upon the keeper 70a (Figure 14) in the direction of the arrow F'2, that is to say in a direction tending to open the said buckle.

To this end, again as in the form of embodiment represented in Figure 2B, means are provided which, when the buckle is in the closed position, prevent the latches 74a and 75a from pivoting in the directions of the arrows f4 and f '4 respectively.

Two distinct features, which could be utilised individually, are provided in this example.

The first of these consists in equipping the push button 100a (Figure 16) with slots or slits 150 and 151 having longitudinal edges 109a and 110a identical with the ramps 109 and 110 of the push button 100 shown in Figure 12. These slots 150 and 151 are likewise limited by opposite longitudinal edges 109b and 110b respectively. It is these latter which tend to prevent rocking of the latches 74a and 75a in the directions of the arrows f4 and f4 respectively when a pull is exerted in the direction F'2 upon the keeper 70a.

The second feature tending to prevent undesired opening of the buckle consists in the provision of two metallic rods 152 and 153 introduced into openings 154 and 155 respectively (Figures 16 and 17) of the push button 100a and disposed in the vincinity of the external edges 74b and 75b of the latches 74a and 75a in such manner as to form a stop preventing the rotation of the said latches in the directions of the arrows f4 and f '4 when the push button 100a is not pressed, that is to say in the position as shown in Figure 14.

When the said push button is pressed (Figure 15), the position of the rods 152 and 153 is such that they no longer form stops which can prevent or limit the pivoting of the latches 74a and 75a. In other words, in this position the rods 152 and 153 permit a pivoting of the said latches through an angle of sufficient value to permit opening of the buckle. It will be noted that these rods 152 and 153, like the ramps 109 and 110, ensure that the buckle is opened only after a displacement of given length of the push button.

In the example the rods 152 and 153 are guided in ports 156 and 157 formed in the plates 72a and 73a and extending parallel with the axis 160. The length of these ports corresponds to the stroke of the push button 100a.

Finally the apertures 92a and 93a of the plates 72a and 73a are closed, that is to say not open on one side as in the form of embodiment as shown in Figure 8.

WHAT WE CLAIM IS: 1. Safety belt buckle comprising a buckle body and a keeper which enters the body, a pair of pivoted latches to engage notches in opposite edges of the keeper thereby to retain the keeper within the body, there being spring means to urge the latches towards one -another into the keeperengaging position, and a push button slidable within the body in the direction of keeper entry into the body, the push button on such sliding in the direction of entry directly engaging the latches to separate them to release the keeper.

2. Safety belt buckle according to claim 1, wherein each latch has a head, a tail and a notch-engaging nose between the head and tail, and is pivoted at its tail farther from the keeper entry than the head, and wherein the push button engages the heads to release the keeper.

3. Safety belt buckle according to claim 2, wherein the push button has features which engage ramps on the latch heads, which ramps are inclined to the direction of sliding of the push button in the buckle body.

4. Safety belt buckle according to claim 3, wherein the push button comprises two parallel walls joined by small bridge pieces whereof the faces most remote from an actuating bar fast with one of the walls carry rods, pins or studs consituting the ramengaging features.

5. Safety belt buckle according to claim 4, characterised in that the rods, pins or studs are metallic pieces attached to the push button, which is advantageously of plastics material.

6. Safety belt buckle according to claim 4 or claim 5, wherein the ramps are formed by edges of or slots in the latches.

7. Safety belt buckle according to claim 3, or claim 4 or claim 5, wherein each bridge piece has a projection directed parallel to the walls, the projections assisting to guide the push button when operated.

8. Safety belt buckle according to claim 2, wherein the push button has ramps inclined in the direction of sliding of the push button, which ramps are engaged by studs projecting perpendicularly from the latch heads.

9. Safety belt buckle according to claim 8, wherein the push button has a pair of opposite walls formed with bosses on which the ramps are formed.

10. Safety belt buckle according to any one of claims 3 to 9, wherein the ramps have an evolutive form such that a large displacement of the push button at first causes only a slight pivoting of the latches.

11. Safety belt buckle according to claims 3 to 7, wherein the ramps have a slope which increases progressively from the latch noses towards the free ends of the latch heads.

12. Safety belt buckle according to claims 8 to 10, wherein the ramps have an inclination in the direction of sliding of the push button which increases progressively from their ends nearer the body entry to their ends remote from the entry.

13. Safety belt buckle according to any one of the preceding claims, comprising stop means to prevent pivoting of the latches in the direction tending to free the keeper when the push button is in a position corresponding to that of closure of the said

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. Two distinct features, which could be utilised individually, are provided in this example. The first of these consists in equipping the push button 100a (Figure 16) with slots or slits 150 and 151 having longitudinal edges 109a and 110a identical with the ramps 109 and 110 of the push button 100 shown in Figure 12. These slots 150 and 151 are likewise limited by opposite longitudinal edges 109b and 110b respectively. It is these latter which tend to prevent rocking of the latches 74a and 75a in the directions of the arrows f4 and f4 respectively when a pull is exerted in the direction F'2 upon the keeper 70a. The second feature tending to prevent undesired opening of the buckle consists in the provision of two metallic rods 152 and 153 introduced into openings 154 and 155 respectively (Figures 16 and 17) of the push button 100a and disposed in the vincinity of the external edges 74b and 75b of the latches 74a and 75a in such manner as to form a stop preventing the rotation of the said latches in the directions of the arrows f4 and f '4 when the push button 100a is not pressed, that is to say in the position as shown in Figure 14. When the said push button is pressed (Figure 15), the position of the rods 152 and 153 is such that they no longer form stops which can prevent or limit the pivoting of the latches 74a and 75a. In other words, in this position the rods 152 and 153 permit a pivoting of the said latches through an angle of sufficient value to permit opening of the buckle. It will be noted that these rods 152 and 153, like the ramps 109 and 110, ensure that the buckle is opened only after a displacement of given length of the push button. In the example the rods 152 and 153 are guided in ports 156 and 157 formed in the plates 72a and 73a and extending parallel with the axis 160. The length of these ports corresponds to the stroke of the push button 100a. Finally the apertures 92a and 93a of the plates 72a and 73a are closed, that is to say not open on one side as in the form of embodiment as shown in Figure 8. WHAT WE CLAIM IS:

1. Safety belt buckle comprising a buckle body and a keeper which enters the body, a pair of pivoted latches to engage notches in opposite edges of the keeper thereby to retain the keeper within the body, there being spring means to urge the latches towards one -another into the keeperengaging position, and a push button slidable within the body in the direction of keeper entry into the body, the push button on such sliding in the direction of entry directly engaging the latches to separate them to release the keeper.

buckle.

14. Safety belt buckle according to claim 11 as appendant to any of claims 3 to 7, wherein there are ports in the latch heads, which ports are shaped to provide the stop means and the ramps.

15. Safety belt buckle according to claim 14, wherein the ports have each a part extending substantially parallel with the direction of sliding of the push button to provide the stop means.

16. Safety belt buckle according to claim 11 as appendent to claim 8 or claim 9, wherein there are slots or ports in the push button, which slots or ports have parts forming the stop means and have edges constituting the ramps to be engaged by the studs.

17. Safety belt buckle according to claim 11, wherein the stop means comprise two members fixed to the push button, each of these forming a stop limiting the pivoting of a latch with which it is associated when the push button is not pressed in but being displaced with the push button to allow release pivoting of the latches after the push button has been pushed in by a given distance for opening the buckle.

18. Safety belt buckle substantially as hereinbefore described with reference to Figures 1 to 6 or these Figures as modified by Figure 2B, or Figures 7 to 13, or Figures 14 to 17 of the drawings.