GB2069587A

GB2069587A - Automatic vehicle-door locking system

Info

Publication number: GB2069587A
Application number: GB8101245A
Authority: GB
Original assignee: Nissan Motor Co Ltd
Current assignee: Nissan Motor Co Ltd
Priority date: 1980-01-16
Filing date: 1981-01-15
Publication date: 1981-08-26
Also published as: JPS56100983A; FR2473602A1; DE3100772A1

Abstract

An automatic door locking system for an automotive vehicle such that all the doors are automatically unlocked when a shock is given to the vehicle in a traffic accident such as a collision. The automatic locking system comprises a shock sensor (21) connected through a timer (22) in parallel with the unlock switch (20) and is turned on when a shock is given to the vehicle. <IMAGE>

Description

SPECIFICATION Automatic door locking system for an automotive vehicle BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates generally to an automatic door locking system for an automotive vehicle, and more particularly to an automatic door locking system such that all the locked doors are automatically unlocked when an extraordinarily great shock, such as a collision, is unfortunately given to the vehicle.

2. Description of the Prior Art As is well-known, prior-art automatic door locking devices utilize electronic, vacuum, and combined electronic-vacuum actuators to control the automatic locking/unlocking of all vehicle doors. Heretofore, however, none of the prior-art devices incorporates a shock sensor that automatically causes the doors to unlock upon being subjected to an external shock, such as a collision. Accordingly, it is necessary to unlock the doors from inside or outside the vehicle when the driver or passengers must urgently escape out of the passenger compartment or be rescued therefrom, thus resulting in a serious accident because of a delay of a proper quick action.

SUMMARY OF THE INVENTION With these problems in mind therefore, it is the primary object of the present invention to provide an automatic door locking system for an automotive vehicle whereby all the doors are automatically unlocked when a shock is given to the vehicle in such a traffic accident as a collision or an upset, so that the driver and passengers can readily escape or be rescued out of the passenger compartment.

To achieve the above-mentioned object, the automatic door locking system of the present invention comprises a shock sensor connected in parallel with a door-unlock switch circuit, in addition to an automatic door locking system for an automotive vehicle.

BRIEF DESCRIPTION OF THE DRAWINGS The features and advantages of the automatic door locking system for an automotive vehicle of the present invention will be more clearly appreciated from the following description taken in conjunction with the accompanying drawings in which like reference numerals designates corresponding elements and in which: Figure 1 is a schematic block diagram of an embodiment of the automatic door locking system according to the present invention; Figure 2 is a detailed circuit diagram of the first timer of Fig. 1; and Figure 3 is a detailed circuit diagram of the second timer of Fig. 1.

DETAILED DESCRIPTION OF THE PRE FERRED EMBODIMENT To facilitate understanding the present invention, with reference to Fig. 1. a detailed description will be made of a speed-responsive automatic door locking system.

When the driver or others operate the door locking knob or cylinder key provided inside or outside the vehicle, a normally-open lock switch 1 6 is turned on. Accordingly, a current is passed from a battery B to ground 31 through a fusible link 1, an ignition switch 2, a fuse 3, a diode 33, a first timer 15, and the lock switch 16, and thereby the first timer 1 5 operates during a predetermined period of time to turn on a transistor 25, thus energizing a lock relay coil 7 by a current being passed therethrough from the battery to ground 26.

With reference to Fig. 2, a more detailed description will be made of the first timer operation. When the lock switch 1 6 is turned on, a current flows from the battery B to ground 31, through a resistor R8 and the lock switch 16, and a voltage develops across the resistor R8. Accordingly, another voltage begins to charge up a condenser C2. Since the emitter and the base of the transistor Tr1 are at almost the same potential the moment the lock switch 1 6 is turned on, Tr, is kept off; however, thereafter since the voltage across the condenser C2 develops gradually in accordance with a time constant, the transistor Tr, is turned on the moment the base voltage drops below the ON-level. When Tr1 is on, another transistor 25 is also turned on, and thus a current is passed through the lock relay coil 7.

With reference to Fig. 1, the lock releasing switch 40 has a movable contact 5 and two fixed contacts 4 and 6 with the movable contact 5 normally brought into contact with the fixed contact 6 in a direction to unlock the doors. The unlock releasing switch 41 has a movable contact 9 and two fixed contacts 8 and 10 with the movable contact 9 normally brought into contact with the fixed contact 10 in a direction to lock the doors.

Therefore, when energized, the lock relay coil 7 actuates the lock releasing switch 40 to switch the movable contact 5 from the fixed contact 6 to the fixed contact 4 in a direction to lock the doors. Accordingly, a current flows from the battery B to ground 26 through the fixed contact 4, the movable contact 5, actuators 12, 1 3 and 14, the movable contact 9, the fixed contact 10. Thus the doors on the passenger side and both the rear sides are all locked.

Further, in this embodiment, although the lock switch 1 6 is automatically turned off immediately after being released, the actuators 12, 1 3 and 14 are kept operational only during the discharge period of the condenser C2. Therefore, the purpose of the condenser C2 is to provide a time lag for the switch action of the actuators when the switch 1 6 is turned on or off.

Next, detailed description will be made of the automatic door unlocking operation with reference to Fig. 1.

When the driver or others operate the unlocking knob or cylinder key provided inside or outside the vehicle, normally-open unlock switch 20 is turned on. Accordingly, a circuit is formed from the battery B to ground 27 through the fusible link 1, the ignition relay switch 2, the fuse 3, the diode 33, an unlock relay coil 11, and the unlock switch 20.

When the unlock relay coil 11 is energized, the unlock releasing switch 41 is switched from the fixed contact 10 to the fixed contact 8. Therefore, a current flows from the battery B to ground 26 through the fixed contact 8, the movable contact 9, actuators 12, 1 3 and 14, the movable contact 5 and the fixed contact 6 in the direction to unlock the doors.

Thus, all the doors are unlocked.

Further, in this embodiment. although it is necessary to keep the unlock switch 20 turned on until the doors are completely unlocked, since the period required to unlock the doors is very short, there will be no problem even if the driver releases the unlock switch immediately after the unlock switch 20 has been turned on. In addition. a couple of zener diodes 24 are connected in parallel with the actuators 12, 1 3 and 14 for protecting them from being damaged by the application of an abnormally high voltage thereto.

Next, an automatic door locking operation at a speed will be described with reference to Fig. 1. The autmatic door locking mechanism serves to lock the doors when the vehicle reaches a predetermined speed, for instance, 10 Km/h, even if the driver forgets to lock the doors.

In this embodiment, when the vehicle reaches a speed of 10 Km/h, a speed switch 1 9 is automatically turned off, and thereby a voltage will be applied to the base of a transistor 28 through a chattering prevention circuit 1 7, which includes a condenser to permit the base current of the transistor 28 to flow continuously even if the movable contact of the speed switch 1 9 vibrates on the fixed contact thereof when turned on, introducing electric chatter to the transistor 28.Since actuator switches 1 8 mounted in the actuators 1 2. 1 3 and 14 are usually turned on except when the actuators are in operation, the transistor 28 is turned on and operates the first timer 1 5 in the same way as when the lock switch 1 6 is turned on, because the transistor 28 and -the actuator switches 1 8 are all connected in parallel with the lock switch 1 6.

There will be described hereinbelow the primary feature of the present invention such that all the doors are automatically unlocked at a collision.

If the vehicle suffers an extraordinarily great shock such as a collision, a shock sensor 21 is turned on (closes) to operate a second timer 22 which is configured in almost the same circuit as the first timer 1 5 With reference to Fig. 3, a more detailed description will be made of the second timer operation. When the unlock switch 21 is turned on (closes), a current flows from the battery B to ground 30, through a resistor R' and the unlock switch 21, and a voltage develops across the resistor R'8. Accordingly, another voltage begins to charge up a conden,- ser C'2.Since the emitter and the base of the transistor Tr1 are almost the same in potential the moment the unlock switch 21 is turned on, Tr', is kept off; however, thereafter since the voltage across the condenser C'2 develops gradually in accordance with a time constant, the transistor Tr', is turned on the moment the base voltage drops below the ON-level.

When Tr', is on, Tr'2 is also turned on and a current is passed through the unlock relay coil 11 to switch the unlock release switch 41 from the fixed contact 10 to the fixed contact 8. Therefore, (see Fig. 1) a current flows from the battery B to ground 26 through the fixed contact 8, the movable contact 9, actuators 12, 1 3 and 14, the movable contact 5 and the fixed contact 6. Thus, all the doors on the passenger side and rear sides are locked.

In the second timer, however, since a condenser C'3 is provided at the base of the transistor Tr', the base potential of the transistor Tr' increases in accordance with another time constant. Therefore, the transistor Tr'1 is automatically turned off after a fixed period.

In other words, the second timer 22 is so designed to energize the unlock relay coil 11, a fixed period after the shock sensor 21 has been turned on, during a predetermined period, for instance, of six seconds, to unlock the doors after the shock or upset has been settled. Thereafter, the actuators 12, 1 3 and 14 are actuated in the same way as when the unlock switch 20 is turned on, because the second timer 22 and the shock sensor 21 are connected in parallel with the unlock switch; 20.

As described above, in the automatic door locking system for an automotive vehicle of the present invention, since a shock sensor is connected in parallel with the unlock switch for the automatic door locking system by which all the doors can be locked/unlocked when the driver operates the inside lock/unlock switch or the outside cylinder key switch provided at the driver's side, it is possible for the driver or the passengers to escape or the rescued out of the passenger compartment, even after a traffic accident such as a collision has unfortunately occurred.

It will be understood by those skilled in the art that the foregoing description is in terms of preferred embodiments of the present invention wherein various changes and modifications may be made without departing from the spirit and scope of the invention, as set forth in the appended claims.

Claims

1. An automatic door locking system for an automotive vehicle which comprises: (a) a plurality of actuators for locking/unlocking the doors; (b) a lock switch for locking all of the doors, said switch being provided at the driver's side; (c) an unlock switch for unlocking all of the doors, said switch being provided at the driver's side; (d) a lock relay coil energized in response to the operation of said lock switch; (e) an unlock relay coil energized in response to the operation of said unlock switch; (f) a lock releasing switch actuated by said lock relay coil to permit a current to flow through said actuators in a direction to lock the doors;; (g) an unlock releasing switch actuated by said unlock relay coil to permit another current to flow through said actuators in a direction to lock the doors, (h) a shock sensor connected in parallel with said unlock switch for energizing said unlock relay coil to actuate said unlock releasing switch, whereby all of the doors are unlocked when a shock is given to the vehicle, and the driver and passengers can urgently escape or be rescued out of the vehicle in an emergency, such as as collision.

2. An automatic door locking system for an automotive vehicle as set forth in claim 1, which further comprises a timer connected in parallel with said unlock switch and in series between said unlock switch and said shock sensor for energizing said unlock relay coil after a fixed period after said shock sensor is turned on, during a fixed period.

3. An automatic door locking system for an automotive vebhicle substantially as hereinbefore described with reference to the accompanying drawings.