GB1585039A - Lock for a vehicle door - Google Patents

Abstract

The door wings of a vehicle door having a locking device are pivoted by means of a rotary column (4), the torque of which is generated by a piston/cylinder drive (7). Arranged in the pushing region of the piston/cylinder drive (7) is a pivotable locking element in the form of a pivoting arm (13) which is controlled by a pneumatic auxiliary drive (16). The piston (8a) of the piston/cylinder drive (7) is provided with a locking rod (11), in the pushing region of which the straight pivoting arm (13) is provided. The pivoting arm (13) is approximately parallel to the locking rod (11). The locking rod (11) is provided with an adjustable stop (14), and an actuating rod (15) of the pneumatic auxiliary drive (16) for the pivoting arm (13) is approximately perpendicular to the locking rod (11). This design ensures that, if the compressed air fails, the door wings remain locked. However, the pivoting arm (13) can easily be released by hand by pulling on the pull cord (19). <IMAGE>

Description

(54) LOCK FOR A VEHICLE DOOR (71) I, ENGELHARD BODE, a citizen of the Federal Republic of Germany, of Wigandstrasse 7b, 3500 Kassel, Federal Republic of Germany, do hereby declare the invention, for which I pray that a patent may be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement: The invention relates to a lock for a vehicle door having leaves which are swung open and shut by rotary columns driven in rotation by a pneumatic piston-in-cylinder motor the piston of which can be locked in position by a pivoted locking element.

In a known lock a piston rod of the pneumatic motor co-operates with a pivoted angled lever actuated by a pneumatic actuator. On the occurrence of a compressed air failure a nose on the end of the angled lever engages with a stop on the piston rod of the motor. A spring in the pneumatic actuator rotates the lever into its locked position, locking the door shut and preventing it from being opened, for example by someone leaning against it.

But this arrangement requires, for correct functioning, an extremely precise coincidence between the nose of the lever and the stop on the piston rod. If either part is inaccurately made, or if the two parts do not coincide precisely, the nose can fail to engage when the compressed air fails, and the door can be opened inadvertently.

Furthermore, if it is then desired to unlock the door, for example in an emergency situation, by rotating the angled lever back by hand, this requires a considerable force to be applied to a bar which is connected to the emergency air cock, because the nose of the angled lever and the stop on the piston rod are held together by a pressure. Under certain circumstances the unlocking of the door by hand in an emergency can present difficulties.

The intention in the present invention is to provide a lock for a vehicle door which depends for its operation less on precision in construction and which can be more easily unlocked in an emergency.

Accordingly, there is provided a lock for use in a vehicle door, the door having leaves which are swung open and shut by rotary columns driven in rotation by a pneumatic piston-in-cylinder motor, and the lock comprising a piston locking rod provided on the piston and carrying a stop, a straight arm pivotal into or out of engagement behind said stop, said arm being disposed substantially parallel with the piston locking rod when it is disengaged from behind said stop, a pneumatic actuator normally fed with compressed air to maintain said straight arm disengaged from behind said stop, said actuator being connected to said straight arm by a connecting rod disposed substantially perpendicular to the piston locking rod, said straight arm pivoting, on failure of the compressed air supply to the actuator, into locking engagement behind said stop to prevent movement of the piston to effect opening rotation of a door leaf column.

The adjustability of the stop on the locking rod and the straightness of the pivoted arm make it possible to correct dimensional inaccuracies easily after manufacture. And the fact that the pivoted arm is approximately parallel to the locking rod makes it easy to disengage it from the stop, this movement being opposed only by the force of the spring contained in the pneumatic lock actuator.

An example of the invention is shown in the drawing, in which: Figure 1 shows a vehicle door with two leaves mounted on rotary columns, each column having at its top end a pneumatic motor and a lock; Figure 2 shows a lock in the locked state; and Figure 3 shows a lock in the unlocked state.

The vehicle door consists of two leaves 1, 2 which are opened and shut, in the known way, by means of rotary columns 3, 4 and arms 5, 6. At its upper end each column has a pneumatic piston-in-cylinder motor 7.

As shown best in Figure 2, each column is rotated by a motor of special construction with a toothed piston rod 8 which acts on a pinion 9 fixed to a shaft 10 connected to the column 4. From the other face of the piston 8a of the motor a locking rod 11 projects out beyond the wall of the motor housing 12, and pivoted on the motor housing there is a straight arm 13, extending approximately parallel to the locking rod 11. Mounted on the locking rod 11 is an adjustable stop 14.

Pivoted to the straight arm 13 and approxi mately perpendicular to the locking rod 11 is the connecting rod 15 of a pneumatic lock actuator 16, whose piston 17 acts against the influence of a spring 18. The lock actuator 16 is supported on the motor housing 12 by a bracket 20.

When the compressed air fails, the spring 18 lifts the straight arm 13 into its locking position, up against the adjustable stop 14.

This locks the door shut by preventing the locking rod 11 and the piston of the motor 7 from moving, and so preventing the column 4 from rotating, even if a push is applied to the door.

Nevertheless, the door can easily be unlocked, if necessary, due to the fact that the connecting rod 15 of the pneumatic lock actuator 16 is approximately perpendicular to the locking rod 11. A slight pull on a cord 19 easily disengages the straight arm 13, this movement being opposed only by the strength of the spring 18.

WHAT I CLAIM IS: 1. A lock for use in a vehicle door, the door having leaves which are open and shut by rotary columns driven in rotation by a pneumatic piston-in-cylinder motor, and the lock comprising a piston locking rod provided on the piston and carrying a stop, a straight arm pivotal into or out of engagement behind said stop, said arm being disposed substantially parallel with the piston locking rod when it is disengaged from behind said stop, a pneumatic actuator normally fed with compressed air to maintain said straight arm disengaged from behind said stop, said actuator being connected to said straight arm by a connecting rod disposed substantially perpendicular to the piston locking rod, said straight arm pivoting, on failure of the compressed air supply to the actuactor, into locking engagement behind said stop to prevent movement of the piston to effect opening rotation of a door leaf column.

2. A lock according to claim 1 wherein the connecting rod is spring biased so as to urge the pivotal straight arm into locking engagement behind the stop on the piston locking rod.

3. A lock according to either of claims 1 or 2, wherein the stop is adjustable longitudinally of the piston locking rod.

4. A lock according to claim 2 including manually operable means acting on the straight arm and which can be operated to disengage said straight arm from behind said stop, said means being operable in opposition to said spring bias.

5. A lock for a vehicle door substantially as hereinbefore described with reference to the accompanying drawings.

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

Claims (5)

**WARNING** start of CLMS field may overlap end of DESC **. Figure 3 shows a lock in the unlocked state. The vehicle door consists of two leaves 1, 2 which are opened and shut, in the known way, by means of rotary columns 3, 4 and arms 5, 6. At its upper end each column has a pneumatic piston-in-cylinder motor 7. As shown best in Figure 2, each column is rotated by a motor of special construction with a toothed piston rod 8 which acts on a pinion 9 fixed to a shaft 10 connected to the column 4. From the other face of the piston 8a of the motor a locking rod 11 projects out beyond the wall of the motor housing 12, and pivoted on the motor housing there is a straight arm 13, extending approximately parallel to the locking rod 11. Mounted on the locking rod 11 is an adjustable stop 14. Pivoted to the straight arm 13 and approxi mately perpendicular to the locking rod 11 is the connecting rod 15 of a pneumatic lock actuator 16, whose piston 17 acts against the influence of a spring 18. The lock actuator 16 is supported on the motor housing 12 by a bracket 20. When the compressed air fails, the spring 18 lifts the straight arm 13 into its locking position, up against the adjustable stop 14. This locks the door shut by preventing the locking rod 11 and the piston of the motor 7 from moving, and so preventing the column 4 from rotating, even if a push is applied to the door. Nevertheless, the door can easily be unlocked, if necessary, due to the fact that the connecting rod 15 of the pneumatic lock actuator 16 is approximately perpendicular to the locking rod 11. A slight pull on a cord 19 easily disengages the straight arm 13, this movement being opposed only by the strength of the spring 18. WHAT I CLAIM IS:

1. A lock for use in a vehicle door, the door having leaves which are open and shut by rotary columns driven in rotation by a pneumatic piston-in-cylinder motor, and the lock comprising a piston locking rod provided on the piston and carrying a stop, a straight arm pivotal into or out of engagement behind said stop, said arm being disposed substantially parallel with the piston locking rod when it is disengaged from behind said stop, a pneumatic actuator normally fed with compressed air to maintain said straight arm disengaged from behind said stop, said actuator being connected to said straight arm by a connecting rod disposed substantially perpendicular to the piston locking rod, said straight arm pivoting, on failure of the compressed air supply to the actuactor, into locking engagement behind said stop to prevent movement of the piston to effect opening rotation of a door leaf column.

2. A lock according to claim 1 wherein the connecting rod is spring biased so as to urge the pivotal straight arm into locking engagement behind the stop on the piston locking rod.

3. A lock according to either of claims 1 or 2, wherein the stop is adjustable longitudinally of the piston locking rod.

4. A lock according to claim 2 including manually operable means acting on the straight arm and which can be operated to disengage said straight arm from behind said stop, said means being operable in opposition to said spring bias.

5. A lock for a vehicle door substantially as hereinbefore described with reference to the accompanying drawings.