GB2307271A

GB2307271A - Automobile door latch

Info

Publication number: GB2307271A
Application number: GB9523685A
Authority: GB
Inventors: John Phillip Chevalier
Original assignee: Individual
Current assignee: Individual
Priority date: 1995-11-20
Filing date: 1995-11-20
Publication date: 1997-05-21
Also published as: WO1997019243A1; GB9523685D0; AU7631396A

Abstract

The present invention concerns a latch of the type utilised to secure automobile doors, boots, bonnets, hoods, and other similar applications. The present invention is characterised in that the indentation 15 of a latch 5 is formed in at least three sides thereof ab, bc, cd, along three circles one thereof is enclosed between the two others, and in that the positioning of an articulated detent lever 20 in relation to the latch allows for an obtuse angle 25 to be defined between the fulcrum 40 of the said detent lever and the pressure surface of a notch 60 with the centre of the articulation pin 35 as the vertex of the said angle. The present invention provides for an improved safety automobile door latch whereby the greater the force applied to force the latch to unlatch the more secure it becomes.

Description

Safety Automobile Door Latch Arrangement The present invention relates to a latch of the type utilised to secure automobile doors bonnets, boots, hoods, and other similar applications.

Automobile door latches comprise a certain mechanical arrangement that serves to effect a controlled movement of a latch bolt from a latched position into an unlatched one and vice versa.

The purpose of automobile door latches is to secure the safety of passengers when on board of a motor vehicle and to allow a controlled access thereto. Also it serves to ensure the security of the vehicle as well as goods left or transported thereby.

The incessant demand for improved automobile safety and security has led to significant efforts being devoted to improving such devices.

The present invention offers an improved safety automobile door latch arrangement.

According to the present invention there is provided a safety automobile door latch arrangement comprising: a pivotable latch 5 capable of retaining a striker 10 by means of a suitably adapted indentation 15 thereof; an articulated detent lever 20 capable of retaining the said latch in a latched position whereby the positioning of the said articulated detent lever in relation to the latch is effected in a manner allowing for an obtuse angle 25 to be defined by a first straight line 30 passing through the centres ofthe articulation pin 35 and the fulcrum 40 of the said articulated detent lever and by a second straight line 45 perpendicular to the radius 50 that extends from the centre of the latch pivot 55 through the pressure surface of an abutment notch 60; the indentation ofthe said latch is characterised in that at least three sides ab, bc, cd, thereof are formed along parts of circumferences of three circles 65 one thereof is at least in one part thereof enclosed between the two others.

Two of the said circles may either be concentric or have independent centres.

The pivot of the said latch and one of the three circles may be enclosed between the two others.

At least one outer side of the said latch may be formed in a suitable manner along an arc-like continuous or broken line.

The present invention can now be explained by way of example with reference to the following drawings.

Figures 1, 2, and 3, show in perspective the various elements ofthe present invention in a number of possible arrangements thereof.

Referring to Figure 1, the present invention is a safety automobile door latch arrangement comprising: a pivotable latch 5 capable of retaining a striker 10 by means of a suitably adapted indentation 15 thereof; an articulated detent lever 20 capable of retaining the said latch in a latched position whereby the positioning of the said articulated detent lever in relation to the latch is effected in a manner allowing for an obtuse angle 25 to be defined by a first straight line 30 passing through the centres of the articulation pin 35 and the fulcrum 40 of the said detent lever and by a second straight line 45 perpendicular to the radius 50 that extends from the centre of the latch pivot 55 through the pressure surface of an abutment notch 60.The indentation of the said latch is characterised in that at least three sides ab, bc, cd, thereof are formed along parts of circumferences of three circles 65 one thereof is at least in one part thereof enclosed between the two others. Two of the said circles share the same centre 75.

Both the concentre 75 and the centre 80 of the said third circle which is enclosed between the two others are located on the circumference of a fourth circle 85 concentric with the pivot of the said latch. The concentre 75 is at equal distances from both centres 55 and 80. This specific arrangement has a particular advantage in that by applying a pull force 90 acting on the said striker, while the said latch is in a latched position, a direct pressure force 95 acting on the pivot 55 ofthe latch and an angular moment force 100 acting around thereof are created thus causing the striker to adhere towards the centre of the pivot of the latch and concomitantly reduce the resultant pressure force 105 acting on the detent lever whereby the greater the said pull force the more would the striker move towards the centre the pivot of the said latch.Equally, the greater the said resultant pressure force acting on the detent lever the more would the detent lever adhere to the latch and the more difficult the unlatching thereof would become. Another important advantage due to the present latch arrangement is the increased stability of the latch as a result of the enlarged contact surface 110 between the striker and the latch.

Figure 2 shows an embodiment of the present invention whereby the indentation sides ab, and cd, are formed along chords oftwo concentric circles 65. A fourth side de, also forms part of the said indentation. The said latch has two opposing outer sides 70. This has the advantage of increasing the resistance to bending of the part of the latch retained in the said striker.

Figure 3 shows two of the circles 65 with independent centres 115 and 120, and an outer side 125 formed partly along a curved line 70 and partly along a broken one 130

Claims

CLAIMS 1) A safety automobile door latch arrangement comprising: a pivotable latch 5 capable of retaining a striker 10 by means of a suitably adapted indentation 15 thereof; an articulated detent lever 20 capable of retaining the said latch in a latched position whereby the positioning of the said articulated detent lever in relation to the latch is effected in a manner allowing for an obtuse angle 25 to be defined by a first straight line 30 passing through the centres of the articulation pin 35 and the fulcrum 40 of the said articulated detent lever and by a second straight line 45 perpendicular to the radius 50 that extends from the centre of the latch pivot 55 through the pressure surface of an abutment notch 60; the indentation ofthe said latch is characterised in that at least three sides ab, bc, cd, thereof are formed along parts of circumferences of three circles 65 one thereof is at least in one part thereof enclosed between the two others.
2) A safety automobile door latch arrangement as described in Claim 1, wherein according to the present invention two of the said three circles may either be concentric or have independent centres.
3) A safety automobile door latch arrangement as described in Claim 1, and Claim 2, wherein in the pivot of the said latch and one of the three circles may partly be enclosed between the two other circles.
4) A safety automobile door latch arrangement as described in Claims 1 to 3, wherein at least one outer side of the said latch may be formed along an arc-like continuous or broken line.
5) A safety automobile door latch arrangement as described in Claims 1 to 4, wherein two of the said three circles are concentric. Such concentre and the centre of the third circle are located on the circumference of a fourth circle that is concentric with the pivot of the latch.

The concentre of the said two circles is located at equal distances from the centre of the pivot ofthe latch and the centre of the third circle.
6) A safety automobile door latch arrangement as hereinbefore described with reference to figures I to 3, of the accompanying drawings.
7) A safety automobile door latch arrangement as claimed in claim 1 wherein either the said articulated detent lever or the said indentation as described hereinbefore retained.