GB2164697A - Door locking mechanism for a vehicle - Google Patents

Abstract

A door locking mechanism for a vehicle comprising a key operated arrangement accessible at the exterior of the vehicle, a door locking device, and linkage means whereby appropriate movements of the barrel of the locking arrangement are transmitted to the locking device to effect locking and unlocking of the door, the key operated arrangement affording first, second and third angularly spaced, predetermined angular positions of the barrel of the key operated arrangement, and the key of the key operated arrangement being removable from the arrangement at least when the barrel is in said first or said second position to leave said barrel locked in said first or said second position, and the coupling of the barrel of the key operated arrangement to said link means being such that angular movement of the barrel of the key operated arrangement from said second position to said first position is transmitted by said link means to said locking device to effect locking of the door, and with said barrel in said first position said link means and therefore said locking device being held against movement in a direction to unlock the door further, said coupling being such that movement of said barrel from said second position to said third position is transmitted by said link means to said locking device to effect unlocking, and when said barrel is in said second position said link means can be moved by means other than said barrel either to effect locking of the locking device, or unlocking of the locking device depend upon whether said barrel was previously in its first position or its third position.

Description

SPECIFICATION Door locking mechanism for a vehicle This invention relates to a door locking mechanism for a vehicle, primarily but not exclusively a road vehicle.

A known road vehicle door locking mechanism includes a lockable latch device which, in its unlocked state, can be actuated by the interior and exterior door handles. Locking and unlocking of the latch device can be effected both by a key operated arrangement at the exterior of the door and by a personal button or lever at the interior of the door. The key operated arrangement and the personal button or lever are individually connected to the locking arrangement of the latch device by rods or similar mechanical linkages. The key operated arrangement is such that the key, and therefore the lock barrel, is rotated in one direction from the rest position, against the action of the spring, to effect locking, and is rotated from the rest position in the opposite direction also against spring bias to effect unlocking.

Thus the lock barrel and the key are always returned to the rest position, and it is only in the rest position that the key can be removed from the barrel. If locking has been effected by the key operated arrangement unlocking can be effected either by the key or by the internal personal button or lever, and vice versa.

A known problem of such conventional door locking mechanisms is that unauthorised unlocking can often be achieved from the exterior of the vehicle without the proper key by passing an appropriate tool between the framework of the door and the window pane carried thereby in order directly to manipulate the rod or other linkage between the latch device and either the key operated arrangement or the internal button or lever. It is an object of the present invention to provide a door locking mechanism for a vehicle wherein this problem is obviated.

In accordance with the present invention there is provided a door locking mechanism for a vehicle comprising a key operated arrangement accessible at the exterior of the vehicle, a door locking device, and linkage means whereby appropriate movements of the barrel of the locking arrangement are transmitted to the locking device to effect locking and unlocking of the door, the key operated arrangement affording first, second and third angularly spaced, predetermined angular positions of the barrel of the key operated arrangement, and the key of the key operated arrangement being removable from the arrangement at least when the barrel is in the first or said second position to leave said barrel locked in said first or said second position, and the coupling of the barrel of the key operated arrangement to said link means being such that angular movement of the barrel of the key operated arrangement from said second position to said first position is transmitted by said link means to said locking device to effect locking of the door, and which said barrel in said first position said link means and therefore said locking device being held against movement in a direction to unlock the door further, said coupling being such that movement of said barrel from said second position to said third position is transmitted by said link means to said locking device to effect unlocking, and when said barrel is in said second position said link means can be moved by means other than said barrel either to effect locking of the locking device, or unlocking of the locking device depend upon whether said barrel was previously in its first position or its third position.

Preferably said barrel is coupled to said link means by way of a finger moveable with the barrel and a drive plate relative to which said barrel is angularly movable, said finger being received in an aperture in said drive plate, and said aperture being so shaped as to permit the barrel to move angularly relative to said drive plate through an angular distance which is not less then the angular distance through which the drive plate must move to drive the locking device between its locked and unlocked conditions.

Conveniently the angular distance between said first and second positions exceeds said angular distance through which said drive plate must move to drive the locking device between said locked and unlocked conditions, and said aperture is so shaped as to permit movement of the drive plate relative to the barrel through an angular distance equal to the distance between said first and second positions.

The invention further resides in a locking kit for use in the conversion of an existing door locking mechanism for a vehicle, said kit comprising a key operated arrangement the barrel of which has first, second and third angularly spaced predetermined positions relative to the cylinder of the arrangement, said first and third positions being spaced on opposite sides respectively of said second position, and said arrangement being such that the operating key can be removed from the arrangement in the first and second angular positions of the barrel to leave the barrel locked relative to the cylinder of the arrangement in said first or said second angular position, a finger member moveable with said barrel, and a drive plate relative to which said barrel is angularly movable, said drive plate having an aperture therein within which said finger member is received, said aperture being elongate in the direction of relative movement of the barrel and drive plate so as to permit relative movement of the barrel and drive plate through a distance not less than the angular distance through which the drive plate must move to drive the locking device between its locked and unlocked conditions, said drive plate further being adapted for connection to link means whereby appropriate movement of the barrel relative to the cylinder of the lock arrangement may, in use, be transmitted to a locking device of the door. Preferably said aperture in said drive plate is an arcuate slot having its center on the axis of rotation of the barrel of the key operated arrangement.

Conveniently said drive plate is provided with a plurality of spaced apertures an appropriate one of which will be selected for connection of the link means to the drive plate.

In the accompanying drawings, Figure 1 is a diagramatic representation of a conventional vehicle door locking mechanism, Figures 2 and 3 illustrate the locked and unlocked states respectively of part of the mechanism illustrated in Fig. 1, Figures 4 and 5 are views similar to Figs. 2 and 3 illustrating transient position of the mechanism, Figure 6 is an exploded perspective view of part of a vehicle door locking mechanism in accordance with one example of the present invention, Figure 7 is an end view of part of the key operated arrangement of Fig. 6, Figure 8 is an equivalent end view of the key of the arrangement, Figures 9 and 10 are side views respectivelyn of the components shown in Figs. 7 and 8, Figure ii is a view similar to Fig. 7 but illustrating the barrel of the locking arrangement in a different position, and Figures 12 and 14 are views illustrating the sequence of movement of part of the mechanism of Fig. 6 during its range of operation.

Referring first to Figs. 1 to 5 of the accompanying drawing the conventional vehicle door locking mechanism includes a locking device 11 affixed to the framework of the vehicle door 12 adjacent an edge 13 thereof. The device 11 co-operates with a striker member secured to the vehicle body adjacent the position occupied by the door edge 13 when the door is closed. The locking device 11 will usually be in the form of a lockable latch which, when in its unlocked state, can be operated to release the door by means of a conventional door handle 14 on the exterior of the door, or by an equivalent handle (not shown) on the interior of the door.The latch can be placed in a locked state (in which it is not operable by the external handle 14 or the equivalent internal handle) either by an externally accessible key operated arrangement 15 or by an internally accessible personal locking button 16. In some vehicles the button 16 is replaced by a lever. Rigid rods 17, 18 or equivalent link members couple the key operated arrangement 15 and the button 16 respectively to the locking assembly of the device 11. The barrel of the key operated arrangement 15 has a single stable position relative to the cylinder of the arrangement and it is only in this single stable position that the operating key be removed leaving the barrel locked against angular movement.

Angular movement of the barrel of the key operated arrangement 15 is transmitted to the link 17 by a drive plate 19. The barrel includes an integral extension 21 which passes through a circular aperture in the drive plate 19 as a loose fit so that angular movement of the drive plate relative to the extension 21 is possible. A drive finger 22 moveable with the barrel extends radially outwardly from the extension 21 and is bent to extend into an arcuate slot 23 in the drive plate 19. The rod 17 is pivotally connected at one end to the drive plate 19. Fig. 2 illustrates the extension 21 in the angular position which it will occupy when the barrel is in its stable position, that is to say with the key removed and with the drive plate 19 in the position which it occupies when the door is locked. It will be seen that the finger 22 is at the counter-clockwise end of the slot 23.Thus if the key is inserted into the barrel and the barrel is rotated in a clockwise direction the barrel extension 21 will move angularly with respect to the plate 19 as permitted by movement of the finger 22 along the slot 23. The barrel can be moved angularly through a total of 90 relative to its respective cylinder, this total movement consisting of 45" of movement on each side of said stable position. A spring (not shown) is included in the mechanism to restore the barrel to its stable position from either end of its permitted range of movement.It will be recognised therefore that if the barrel is rotated in a counter-clockwise direction from its stable position then abutment of the finger 22 with the counter-clockwise end of the slot 23 will move the drive plate 19 in a counterclockwise direction to achieve a position as shown in Fig. 5. It will be noted that the plate 19 has been moved through 45" from the position shown in Fig. 2, and this movement is transmitted by the rod 17 to the device 11 to unlock the device 11 and thus to unlock the door. It will be noted in Fig. 5 that the extension 21 is illustrated in broken lines in order to indicate that the position of the extension is an unstable position. Upon release of the key the spring will restore the barrel through 45" to its stable position as shown in Fig. 3 wherein the key may be removed from the barrel. It will be noted in Fig. 3 that although the barrel has returned through 45" in a clockwise direction the position of the plate 19 has not been changed from that shown in Fig. 5 since the finger 22 has simply traversed the length of the slot 23. Fig. 4 illustrates the unstable position of the barrel which is achieved by rotating the barrel through 45" from the stable position in a clockwise direction starting from the position of the component shown in Fig. 3. This movement effects locking of the device 11 and upon release of the key in the Fig. 4 position the barrel and its extension 21 reverts to the position shown in Fig. 2.

Locking and unlocking of the device 11 by means of the key operated arrangement 15 is accompanied by equivalent movement of the button 16 since the button 16 is connected to the device 11 through the rod 18. Similarly irrespective of the presence or otherwise of the key in the barrel of the arrangement 15 the device 11 can be locked and unlocked from the interior of the car by depressing or lifting (as appropriate) the button 16. It will be understood from reference to Figs. 2 and 3 that if the device 11 is locked then even though the extension 21 of the barrel cannot move from the stable position, the rod 17 and the plate 19 can be moved as it necessary to effect unlocking, by virtue of the elongate slot 23. In effect the slot moves relative to the finger 22 in these conditions.Similar comments apply to locking without the key when the device 11 is previously in an unlocked condition.

It is a known problem of such mechanisms that unauthorised unlocking can be achieved from the exterior of the vehicle by passing an appropriate tool between the framework of the door 12 and the window pane 20 of the door, the tool being manipulated to move either the rod 1 7 or the rod 18 o effect unlocking of the device 11. Just as this movement of the rod 1 7 is not prevented by the key operated arrangement 1 5 when the movement originates from the button 16, it will not be prevented when the movement originates from unauthorised use of a tool introduced between the framework of the door and the window pane.

Attempts to overcome this disadvantage have included the use of additional locking devices totally independent of the existing mechanism, but such devices suffer from the disadvantage that drilling of apertures in the door structure is necessary in order to fit the devices.

In accordance with the present invention the key operated arrangement of the locking mechanism is quite different in its operation from the conventional key operated arrangement.

Referring now to the example of the invention illustrated in Figs. 6 to 14 it can be seen that the key operated arrangement comprises a cylinder 30 which, in use is held against movement and within which a barrel 31 can be rotated by means of an appropriate key 32. The cylinder 30 includes an escutcheon 32 which is presented outwardly of the vehicle door in use, and which defines a rearwardly facing peripheral flange 33 which engages the door outer surface. The cylinder also includes a spigot 34 projecting rearwardly from the flange 33.. The spigot 34 has a pair of diametrically opposed flats one of which is shown at 35 and includes a region 36 which is screw threaded. In use the spigot 34 passes through an aperture in the door of the vehicle and if necessary a sealing washer is interposed between the outer surface of the door and the flange 33.A locking washer 37 is then threaded over the spigot 34, the aperture of the locking washer corresponding in shape to the cross-sectional shape of the spigot. The locking washer 37 co-operates with the aperture in the vehicle door, and with the spigot 34 to resist rotation of the cylinder 30 within the aperture of the door. A lock nut 38 is then engaged with the threaded portion 36 of the spigot 34 to clamp the cylinder in position on the door.

The barrel 31 includes a rearwardly projecting extension 39 shaped to incorporate a pair of axially extending diametrically opposed parallel flat surfaces 41, and including a screw threaded end region 42. As with the spigot 34 the extension 39 is, by virtue of the axially extending flat surfaces, of so called "double -D" cross-section.

The key 32 is an annular key which is inserted into the annular gap 43 defined between the barrel 31 and the cylinder 30. The outer peripheral surface of the key 32 has a number of angularly spaced axially extending grooves which extend for different lengths along the key, and which co-act with axially extending pins within the cylinder. The correct key depresses the pins to free the barrel for rotation within the cylinder. The barrel includes a location notch 44 and the key 32 includes internally a location rib 45 which must engage in the notch 44 in order to insert the key.

Thus there is only a single correct orientation of the key 32 relative to the barrel 31. It will be noted that the key 32 also includes a radially outwardly extending pin 46 which, during insertion and withdrawal of the key can pass through either of a pair of angularly spaced notches 47, 48 in the wall of the cylinder 30.

When the key is fully inserted into the cylinder and the locking pins have been depressed by the key then the barrel 31 can be rotated by the key, the pin 46 at this time being engaged in circumferentally extending groove within the cylinder 30. The notches 47 and 48 are spaced apart by 90 and define first and second angular positions of the barrel 31 relative to the cylinder 30 at which the key can be removed. In both positions removal of key leaves the barrel locked relative to the cylinder 30. Although the notches 47 and 48 are spaced apart by 90" the freedom of movement of the barrel within the cylinder, when the appropriate key is inserted, is greater than 90 as will become clear hereafter.

Angularly moveable on the extension 39 of the barrel 31 is a drive plate 49 which fulfils a function similar to that of the drive plate 19 described with reference to Figs. 1 to 5. The drive plate is formed as a stamping from mild steel sheet and has a circular aperture 51 adjacent one end through which the extension 39 extends. Adjacent the aperture 51 is an arcuate slot 52 the centre of curvature of which coincides with the centre of the aperture 51 and the angular extent of which is slightly greater than 90 . The remainder of the plate 49 is provided with a plurality of spaced apertures 53 to permit engagement of the rod 17 with the plate 49. Non-rotatably engaged on the extension 39 is a finger member 54 in the form of a steel pressing having an aperture 55 of "double-D" shape corresponding to the cross-section of the extension 39.The member 54 includes a radial finger 56 which is bent at its free end to engage in the slot 52 of the plate 49. A lock nut 57 holds the finger member 54 and plate 49 on the extension 39 and if desired a spacer member may pass through the aperture 51, around the extension 39 to accept the clamping force imposed by the nut 57 thus faciliting clamping in position of the finger member 54 without the risk of impeding the freedom of angular movement of the drive plate 49 of the extension 39.

A cotter pin 58 can be inserted through a transverse bore of the extension 39 to prevent inadvertent loss of the nut 57.

When in use the barrel 31 has three recognised angularly spaced positions in relation to the cylinder 30. The first position is that shown in Fig. 7 where the notch 44 is aligned the notch 47. The second position is as shown in Fig. 11 where the barrel has been turned through 90 in a counter-clockwise direction and the notch 44 aligns with the notch 48. The third position is achieved by rotating the barrel through a further 45 in a counterclockwise direction and in this position the notch 44 is not aligned with either of the notches 47, 48 and so the operating key 32 cannot be removed.

Fig. 12 illustrates the position of the drive plate 49 and the extension 39 when the barrel is in its first angular position, and it can be seen that the drive plate 49 has been displaced in a clockwise direction to pull on the rod 17 and thus lock the locking device 11 of the door. The drive plate 49 is held in this position by engagement of the finger 56 with the clockwise end of the arcuate slot 52.

Thus if the key 32 is removed from the cylinder 30 the barrel 31 and thus the plate 49 and the link 17 are locked in position and the device 11 cannot be unlocked by the button 16, or by a tool introduced into the door to attempt unlocking by manipulation of the rod 17 or the rod 18.

Movement of the barrel 31 to its second position does not affect the position of the plate 49 since the finger 56 simply traverses the length of the slot 52. However; movement of the barrel beyond the second position through an additional 45 in a counterclockwise direction to reach the third position carries the plate 49 through 45 also. This 45 movement of the plate 49 and rod 17 is sufficient to unlock the device 11 (Fig. 13).

However, in the third position of the barrel it is not possible to remove the key and in order to remove the key the barrel must be returned through 45 back to its second position (Figure 14). The return movement through 45 does not alter the position of the plate 49 since the finger 56 simply tranverses half the length of the slot 52 and thus remains at the mid-point of the slot. The key can now be removed leaving the device 11 unlocked. Furthermore, in the second position of the barrel the plate 49 can be moved in either direction through 45 in relation to the barrel. Thus with the barrel in its second position the device 11 can be locked or unlocked by means of the button 16.It will be recognised therefore that when the barrel is in its first position the device 11 is locked and cannot be unlocked except with the key 32 whereas when the barrel is in its second position normal operation of the device 11 can be achieved by means of the button 16 from the interior of the vehicle.

It will be recognised that the invention is particular suitable for DIY fitting in that the owner of a vehicle can readily remove the existing key operated arrangement and drive plate 19, and substitute in its place for example the key operated arrangement 30, 31, 32 and the associated drive plate 49. By virtue of the plurality of spaced apertures 53 in the drive plate 49 a single drive plate can be used for a wide variety of different vehicles. The owner will simply select the most appropriate aperture 53 for engagement of the existing rod 17. Since the key operated assembly is replacing the existing key operated assembly then no additional holes in the body panels of the vehicle are required.

Claims (6)

1. A door locking mechanism for a vehicle comprising a key operated arrangement accessible at the exterior of the vehicle, a door locking device, and linkage means whereby appropriate movements of the barrel of the locking arrangement are transmitted to the locking device to effect locking and unlocking of the door, the key operated arrangement affording first, second and third angularly spaced, predetermined angular positions of the barrel of the key operated arrangement, and the key of the key operated arrangement being removable from the arrangement at least when the barrel is in said first or said second position to leave said barrel locked in said first or said second position, and the coupling of the barrel of the key operated arrangement to said link means being such thet angular movement of the barrel of the key operated arrangement from said second position to said first position is transmitted by said link means to said locking device to effect locking of the door, and said barrel in said first position said link means and therefore said locking device being held against movement in a direction to unlock the door further, said coupling being such that movement of said barrel from said second position to said third position is transmitted by said link means to said locking device to effect unlocking, and when said barrel is in said second position said link means can be moved by means other than said barrel either to effect locking of the locking device, or unlocking of the locking device depend upon whether said barrel was previously in its first position or its third position.

2. A door locking mechanism as claimed in Claim 1 wherein said barrel is coupled to said link means by way of a finger moveable with the barrel and a drive plate relative to which said barrel is angularly moveable, said finger being received in an aperture in said drive plate, and said aperture being so shaped as to permit the barrel to move angularly relative to said drive plate through an angular distance which is not less than the angular distance through which the drive plate must move to drive the locking device between its locked and unlocked conditions.

3. A door locking mechanism as claimed in Claim 1 or Claim 2 wherein the angular distance between said first and second positions exceeds said angular distance through which said drive plate must move to drive the locking device between said locked and unlocked conditions, and said aperture is so shaped as to permit movement of the drive plate relative to the barrel through an angular distance equal to the distance between said first and second positions.

4. A door locking mechanism substantially as hereinbefore described with reference to Figs. 6 to 14 of the accompanying drawings.

5. A locking kit for use in the conversion of an existing door locking mechanism for a vehicle, said kit comprising a key operated arrangement the barrel of which has first, second and third angularly spaced predetermined positions relative to the cylinder of the arrangement, said first and third positions being spaced on opposite sides respectively of said second position, and said arrangement being such that the operating key can be removed from the arrangement in the first and second angular positions of the barrel to leave the barrel locked relative to the cylinder of the arrangement in said first or said second angular position, a finger member moveable with said barrel, and a drive plate relative to which said barrel is angularly movable, said drive plate having an aperture therein within which said finger member is received, said aperture being elongate in the direction of relative movement of the barrel and drive plate so as to permit relative movement of the barrel and drive plate through a distance not less than the angular distance through which the drive plate must move to drive the locking device between its locked and unlocked conditions, said drive plate further being adapted for connection to link means whereby appropriate movement of the barrel relative to the cylinder of the lock arrangement may, in use, be transmitted to a locking device of the door.

Preferably said aperture in said drive plate is an arcuate slot having its center on the axis of rotation of the barrel of the key operated arrangement.

6. A locking kit substantially as hereinbefore described with reference to Figs 6 to 14 of the accompanying drawings.