Seat belt buckle

Information

  • Patent Grant
  • 6418596
  • Patent Number
    6,418,596
  • Date Filed
    Thursday, January 4, 2001
    23 years ago
  • Date Issued
    Tuesday, July 16, 2002
    22 years ago
  • Inventors
  • Original Assignees
  • Examiners
    • Sandy; Robert J.
    Agents
    • Tarolli, Sundheim, Covell, Tummino & Szabo L.L.P.
Abstract
A seat belt buckle having a release button for a latch slidably mounted on a frame, an ejector for an insert tongue and at least one connecting element. The connecting element is shiftable between a working position, in which it makes a connection between the ejector and the release button, and a resting position in which it breaks the connection between the ejector and release button. A dislocator is provided on the frame, which dislocates the connecting element from the resting position into the working position when the ejector is shifted out of place.
Description




FIELD OF THE INVENTION




The invention relates to a seat belt buckle comprising a release button for a latch slidably mounted on a frame, and an ejector for an insert tongue.




BACKGROUND OF THE INVENTION




Known from DE 296 13 690 is one such buckle provided with a balance weight to prevent the release button from shifting out of place relative to the buckle when exposed to a heavy acceleration or deceleration in the longitudinal direction of the buckle due to its mass inertia and thus opening the buckle unintentionally. Inspite of this, unintentional opening may occur with this type of buckle when, for instance, the buckle is heavily accelerated by a belt tensioner and then abruptly decelerated on impacting a stopper. Since the belt tensioner has a certain clearance with respect to the release button it still has an impulse when the release button is already at rest. Since, however, the ejector needs to be mechanically coupled to the release button so that it is able to activate the latch on insertion of the insert tongue, this impulse is passed on via the ejector to the release button. At the point in time of impulse transfer, however, the compensation of the inertia by the balancing weight is no longer effective, since this is likewise at rest. When the impulse transmitted is sufficiently large there is thus the risk of the release button being shifted out of place, thus opening the buckle.




The invention provides a seat belt buckle in which with the insert tongue inserted any impulse transfer from the insert tongue to the release button is reliably prevented.




BRIEF DESCRIPTION OF THE INVENTION




This is achieved with a seat belt buckle comprising a release button for a latch slidably mounted on a frame, an ejector for an insert tongue and at least one connecting element, the connecting element being shiftable between a working position, in which it makes a connection between the ejector and the release button, and a resting position in which it breaks the connection between the ejector and release button, a dislocator being provided on the frame which dislocates the connecting element from the resting position into the working position when the ejector is shifted out of place. Coupling only takes place when necessary, namely on insertion of the insert tongue, thus reliably preventing any impulse transfer from the insert tongue to the release button with the insert tongue inserted.




In accordance with the preferred embodiment of the invention the connecting element consists of a shifter formed on the ejector, and the dislocator is configured as a ramp on the frame on which the shifter slides when the ejector is shifted out of place and the length of the ramp is selected so that at the end of the shifting travel of the ejector the shifter is released from the ramp to fall back into its resting position. Compared to conventional buckles, this embodiment provides the advantage that no additional components are required. Only the configuration of two components, namely frame and ejector, needs to be modified.











Further advantages and features of the invention read from the following description of the preferred embodiment and are evident from the attached drawings to which reference is made and in which:




BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a cross-section through a buckle including an insert tongue in accordance with the preferred embodiment of the invention;





FIG. 2

is an isometric view of a first component of the buckle as shown in

FIG. 1

;





FIG. 3

is an isometric view of a second component of the buckle as shown in

FIG. 1

;





FIGS. 4

to


7


each illustrate a detail on a magnified scale of a cross-section through the buckle as shown in

FIG. 1

in sequential phases of inserting the insert tongue; and





FIG. 8

is a detail on a magnified scale of a cross-section through the buckle as shown in

FIG. 1

on release of the insert tongue.











DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT




Referring now to

FIG. 1

there is illustrated a buckle


10


in accordance with the invention and a matching insert tongue


12


. The buckle


10


includes a housing


14


and a frame


16


. Shiftably guided on the frame


16


is a release button


18


. The release button


18


is provided with two slaved pins


20


, only one of which is evident in the Figure. Provided at the front side (on the left in the Figure) of the buckle


10


in the housing


14


is an insertion opening


22


into which the insert tongue


12


is insertable. The buckle is in addition provided with a device


24


preventing the release button


18


from shifting out of place when exposed to a heavy acceleration, for instance, on activation of a belt tensioner, due to its own inertial mass relative to the frame


16


. This device


24


may be of the kind as detailled in DE 296 13 690. The configuration and functioning of the device


24


is irrelevant to describing the present invention, this being the reason why no details are given thereof in the present.




Referring now to

FIG. 2

there is illustrated the frame


16


consisting subtantially of two parallel plates


16




a


,


16




b


. The frame may be stamped to advantage from a metal sheet upswept in the middle transversely to its longitudinal extent so that the two parallel sheet metal halves as plates


16




a


,


16




b


form an interspace and are joined at the front side via U-shaped webs


25


. Stamped out in the upper plate


16




a


are two parallel slots


26


, a dislocator in the form of a key


27


protruding from the outer longitudinal side of each slot into the slot


26


. The portion of this key


27


pointing to the front side of the frame


16


is downswept into the interspace between the two plates


16




a


,


16




b


and forms as viewed from the front side of the frame a ramp


28


leading from the interspace to the upper side of the upper plate


16




a.






Stamped out from the plates


16




a


,


16




b


at surface areas facing each other are two cylindrical protuberances


29


each, extending into the interspace. In this arrangement each of the protuberances


29


of the upper plates


16




a


is located opposite a protuberance


29


of the lower plate


16




b


and is in contact therewith in the interspace.




Referring now to

FIG. 3

there is illustrated in detail an ejector


30


slidably mounted in the frame


16


for ejecting the insert tongue


12


. The ejector


30


comprises two parallel arms


32


connected to each other by a web


34


at one of their ends. Configured at the other end of the arms


32


in each case is a hook


36


pointing outwards. Formed in the middle of the web


34


is a finger


38


parallel to the arms


32


. Likewise formed on the arms


32


between the arms


32


and the finger


38


are two connecting elements in the form of pushers


40


. Each pusher


40


consists of a buffer


42


oriented subtantially parallel to the web


34


, the buffer


42


being connected to the web


34


by a slim member


44


. The member


44


is oriented roughly in the direction of the arms


32


slightly inclined from a plane formed by the arms


32


. Due to the flexure of its member


44


the pusher


40


can be bent from its resting position into a working position in which the buffer


42


protrudes between the upper plates


16




a


of the frame


16


(see FIG.


5


). The ejector


30


is biased in the direction of the insertion opening


22


by a spring


46


mounted on the finger


38


(FIG.


1


), it contacting the protuberances


29


with the hook


36


when the insert tongue


12


is not inserted. The ejector


30


may be fabricated cost-effectively as an injection molded plastics part. In this case the pusher


40


can be molded at no additional expense.




Referring now to

FIGS. 4 and 5

there is illustrated a latch


48


provided in the buckle


10


serving to latch the insert tongue


12


in place, the latch


48


being slidably mounted transversely to the direction of movement of the ejector


30


between a release position and a latching position (see FIG.


7


). The latch


48


can be released by the release button


18


so that it moves into its latching position in which it engages an opening


50


in the inserted insert tongue


12


, the tongue being thereby latched in place in the buckle


10


.




Referring now to

FIGS. 4

to


7


the functioning of the buckle


10


will now be described for a normal insertion of the insert tongue


12


. The latch


48


is maintained in its release position by a first connecting link


52


(

FIG. 7

) at the release button


18


. The insert tongue


12


is guided into the insertion opening


22


at the front side of the buckle


10


. On insertion of the insert tongue


12


it urges the ejector


30


to the rear against the bias from the spring


46


, i.e. in the direction of the slaved pin


20


(FIG.


4


). In further shifting of the insert tongue


12


the buffer


42


of the pusher


40


slides on the ramp


28


so that the buffer


42


is urged upwards with flexing of the member


44


into the working position (FIG.


5


). This results in the buffer


42


coming into contact with the slaved pin


20


so that the ejector


30


is now able to shift the release button


18


to the rear by means of the pusher


40


(FIG.


6


). Due to this shift the first connecting link


52


releases the latch


48


so that it is moved into its latching position in which it engages the opening


50


in the insert tongue


12


. The length of the ramp


28


is dimensioned so that as soon as the release button


18


has been shifted far enough between the slaved pins


20


to thus release the latch


48


, the buffer


42


has attained the rear end of the ramp


28


and thus drops back again into its resting position due to the flexible spring action of the member


44


(FIG.


7


).




Referring now to

FIG. 8

, to release the latch the release button


18


needs to be urged to the rear. In this arrangement the latch


48


is shifted by a second connecting link


54


at the release button


18


from its latching position into the release position to thus re-release the insert tongue


12


.




Should the buckle


10


be shock loaded from the rear with the insert tongue


12


inserted and latched in place, as happens for instance on activation of a belt tensioner when the buckle


10


impacts a stopper, then both insert tongue


12


and release button


18


are exposed to heavy acceleration. Due to their mass inertia both attempt to move to the rear relative to the frame


16


. Because of the aforementioned device


24


the release button


18


is prevented from shifting out of place relative to the frame


16


. However, since the insert tongue


12


also comprises a certain clearance relative to the buckle


10


, it may happen that the insert tongue is still on the move when the release button


18


is already at rest. But since the pusher


40


is in its resting position the connection between ejector


30


and slaved pins


20


is effectively broken to thus prevent the insert tongue


12


—which due to its mass being relatively large as compared to that of the release button


18


has a large impulse—from passing on this impulse to the release button


18


by means of a flexible jolt via the ejector


30


.




Now, the pusher


40


cannot be returned to its working position until the buffer


42


has been moved under the ramp


28


through to the front end thereof. The length of the pusher


40


and the position of the ramp


28


on the frame


16


are selected, however, so that this is only possible when the latch


48


has been removed from the opening


50


by the urging of the release button


18


so that the ejector


30


is able to shift the insert tongue


12


in the direction of the insertion opening


22


(FIG.


8


).



Claims
  • 1. A seat belt buckle comprising a release button for a latch slidably mounted on a frame, an ejector for an insert tongue and at least one connecting element, said connecting element being shiftable between a working position, in which it makes a connection between said ejector and said release button, and a resting position in which it breaks said connection between said ejector and release button, a dislocator being provided on said frame, dislocating said connecting element from said resting position into said working position when said ejector is shifted out of place.
  • 2. The buckle of claim 1, wherein said connecting element is biased into said resting position by force of a spring.
  • 3. The buckle of claim 1, wherein said connecting element consists of a shifter formed on said ejector and said dislocator is configured as a ramp on said frame, on which said shifter slides when said ejector is shifted out of place.
  • 4. The buckle of claim 3, wherein the length of said ramp is selected so that at the end of the shifting travel of said ejector said shifter is released from said ramp to fall back into said resting position.
Priority Claims (1)
Number Date Country Kind
200 00 869 Jan 2000 DE
US Referenced Citations (9)
Number Name Date Kind
3955056 Lindblad May 1976 A
4566161 Ashworth et al. Jan 1986 A
4597141 Wier Jul 1986 A
4621394 Wier Nov 1986 A
4802266 Doty et al. Feb 1989 A
4998328 Tanaka Mar 1991 A
5067212 Ellis Nov 1991 A
5596795 Beisswenger Jan 1997 A
5765266 Betz Jun 1998 A