Locking device for vehicles, particularly for vehicle doors

A locking device for vehicles, particularly for vehicle doors has a mechanical revolving connection between a cylinder core of a lock cylinder and a safety lever of an assigned lock which comprises a driving coupling in the form of a lock nut. In order to achieve a simplification of the construction and mounting of the locking device while ensuring the operability of the locking device when it is operated mechanically as well as when the central locking system is operated, the lock nut is constructed in one piece. An end side of the lock nut facing an operating lever arm of the safety lever has two stops spaced angularly from one another and projecting from the end side. The operating lever arm engages between the stops, so that when the lock nut is rotated, a locking or unlocking position of the safety lever is achieved after an idling path. For the scanning of switches of a central locking system, two cams are arranged on the circumference of the one-piece lock nut which, with respect to one another, have a different angular position with respect to the lock nut circumference and are arranged relative to the stops in the circumferential direction in such a manner that, when the lock nut is rotated, the corresponding cam operates the respective assigned switch of the central locking system before one of the stops engages in the operating lever arm of the safety lever.

BACKGROUND AND SUMMARY OF THE INVENTION 
This invention relates to a locking device for vehicles, particularly for 
vehicle doors of the type having a rotatable locking cylinder operable to 
control a central locking system as well as a safety locking lever. 
A locking device of the construction of the above-mentioned type is known 
from German Patent Document DE 38 27 564 C2. The locking device described 
there contains a lock cylinder with a cylinder core into which a key can 
be non-rotatably inserted. The cylinder core is also non-rotatably 
connected with a revolving connection device constructed as a revolving 
rod which, by means of its end facing away from the lock cylinder, is 
fitted into a two-part lock nut which is rotatably disposed on the main 
plate. The lock nut consists of two shell bodies which are rotatably 
disposed on one another and are coupled with one another by way of a free 
running play while forming a driving connection. For this purpose, the 
front shell body driven by the revolving rod has a driving cam which 
engages in a circle-segment-type recess of the rear output-side shell body 
and can be rotated in it between the recess ends. After rotating the front 
shell body by way of the rotation of the cylinder core and the revolving 
rod fixedly connected with this cylinder core, after the free-running play 
in the recess, the rear shell body is also rotated. On its side facing 
away from the lock cylinder, the rear shell body has a driving pin which 
engages in an oblong hole of an operating lever arm of a lock-side safety 
lever. As the result of the rotation of the rear shell body, the safety 
lever is locked or unlocked depending on the rotating direction. On the 
circumference of the front shell body, two trip cams are arranged which 
are spaced away from one another on the circumference and whose contours 
are scanned by a switch of the central locking system. The central locking 
system is in each case triggered by the cam before the rear shell body can 
operate the safety lever. The front shell body therefore limits its 
function to the triggering of the central locking system, while the rear 
shell body has the function of mechanically operating, after another 
rotation of the key, the safety lever in the case of a failure of the 
central locking system. 
Furthermore, it is known from German Patent Document DE 39 41 086 A1 that 
the position of the lock nut is scanned on the circumference of a 
one-piece lock nut, in which case two coding segments are arranged in an 
axially spaced manner on the circumferential surface of the lock nut and 
cover partial surfaces of different sizes. In this case, the coding 
segments have different angular positions with respect to the 
circumference of the lock nut and are arranged relative to one another 
such that, corresponding sensors are activated or that these sensors 
address a central locking system in the case of a rotation of the lock 
nut. 
It is an object of the invention to further develop a locking device of the 
above-mentioned type in such a manner that its construction and mounting 
are simplified while the operability of the locking device is ensured when 
it is operated mechanically as well as when the central locking system is 
operated. 
According to preferred embodiments of the invention, this object is 
achieved by providing an arrangement wherein the lock nut is constructed 
in one piece, two stops being arranged on an end side of the lock nut 
facing an operating lever arm of the safety lever, said stops being spaced 
away from one another by an angle of rotation and projecting from the end 
side and by means of which the operating lever arm situated between them 
during the rotation of the lock nut can be operated by way of the 
revolving connection device for the taking-up of a locking or unlocking 
position of the safety lever after an idle path, and wherein two cams are 
provided on the circumference of the lock nut for the scanning of switches 
of the central locking system, which cams have a different angular 
position to one another with respect to the circumference of the lock nut, 
said cams being arranged relative to the stops in the circumferential 
direction such that, when the lock nut is rotated, a corresponding cam 
operates the respective assigned switch of the central locking system as a 
function of the rotating direction, before one of the stops engages in the 
operating lever arm of the safety lever. 
Because of the one-piece construction of the lock nut, and thus the 
elimination of a second lock nut part, and the free-running play displaced 
directly to the engaging of the lock nut with the safety lever for the 
unlocking and locking of the locking device, its construction is 
considerably simplified. In this case, the switching of the central 
locking system and the mechanical operability of the safety lever is 
concentrated on a single component. This clearly not only reduces the 
manufacturing costs of the locking device but the mounting is also 
facilitated by the simple axial clipping-in of the lock nut in one 
direction. The mounting of the lock cylinder is also improved because only 
the angular position of the nut relative to the lock cylinder must be 
fixed. In addition, it is advantageous that the manufacturing tolerances, 
which add up in the case of several components, will be eliminated, so 
that an improved switching point precision exists for the central locking 
system. Furthermore, an improved stability of the mechanical drive is 
obtained. 
Other objects, advantages and novel features of the present invention will 
become apparent from the following detailed description of the invention 
when considered in conjunction with the accompanying drawings.

DETAILED DESCRIPTION OF THE DRAWINGS 
FIGS. 1 to 3 illustrate a one-piece lock nut 1 on whose front side or end 
side 2, which faces away from the lock cylinder, a crescent-shaped wall 3 
is formed which extends along the circumference and projects from the end 
side 2. The two wall ends 4, 5 have an angular distance of approximately 
1350.degree. with respect to one another and, by means of their points 6, 
form stops for an end 7 of an operating lever arm 8 situated in-between in 
this angle area , which operating lever arm is arranged opposite to the 
end side 2 of the lock nut 1 and is part of a swivellably disposed safety 
lever 9 of the locking device 10. The double-wing-type end 18 of a 
revolving rod is non-rotatably fitted into a receiving opening 17 of the 
lock nut 1 and is non-rotatably connected with the cylinder core of the 
lock cylinder. 
FIG. 1 shows an inoperative position of the locking device 10 in which, in 
a spring-loaded manner, the lock nut 1 is rotated back into a 
corresponding withdrawal position of a key which can be inserted into the 
lock core of the lock cylinder. In this case, the wall ends 4, 5 are 
disengaged from the operating lever arm 8 of the safety lever situated in 
the unlocked position. 
When, according to FIG. 2, the key and therefore the cylinder core as well 
as the revolving rod and the lock nut 1 are rotated for the locking of the 
locking device 10, after an idle path extending in the circumferential 
direction, the tip 6 of the wall end 4 engages in a corresponding engaging 
recess 11 arranged in a negative-mold-type manner on the end 7 of the 
operating lever arm 8, in which case, after a further rotation of the lock 
nut 1, the operating lever arm 8 is caused by the wall end 4 to carry out 
a swivelling movement in the opposite direction, after which the safety 
lever 9 takes up its locking position. 
For the unlocking of the locking device 10 according to FIG. 3, the lock 
nut 1 is rotated opposite to the rotating direction taking place during 
the locking movement, in the case of which, after a circumferential idling 
path--the free running play--the wall end 5 engages by means of its point 
6 in a corresponding engaging recess 12 arranged in a negative-mold-type 
manner on the end 7 of the operating lever arm 8. As a result, during a 
further rotation of the lock nut 1, the operating lever arm 8 is swivelled 
back, after which the safety lever 9 takes up its unlocked position. 
Embodiments are also contemplated where the lock nut 1 can be rotated in a 
spring-loaded manner back into the inoperative position or the withdrawal 
position of the key when the locked or unlocked position is reached 
without any change of the achieved locking position. 
The wall ends 4, 5 are advantageously constructed as points 6 so that a 
sliding-off of the ends 4, 5 and a change of contact is avoided which 
would occur in the case of a plane construction of the ends 4, 5 on the 
operating lever arm 8. This ensures a homogeneous sequence of movements 
during the locking and unlocking. 
Before the operating of the safety lever 9 by means of the wall ends 4 or 
5--depending on the rotating direction--two trip cams 13, 14, which are 
arranged on the circumference of the lock nut 1 and are spaced axially 
from the crescent-shaped wall 3 in the direction of the lock cylinder, are 
caused to engage by means of their control contours with switches 15, 16 
of a central locking system, one of the trip cams 13, 14 initiating the 
unlocking and the other initiating the locking (FIG. 4). The relative 
rotating position of the trip cams 13, 14 is determined such that defined 
switching points are obtained for the operating of the automatic locking 
device and the mechanical operation without the occurrence of interactions 
between the two locking methods which interfere with the operation. 
Although the invention has been described and illustrated in detail, it is 
to be clearly understood that the same is by way of illustration and 
example, and is not to be taken by way of limitation. The spirit and scope 
of the present invention are to be limited only by the terms of the 
appended claims.