This application claims priority to United Kingdom Patent Application GB 0309266.5 filed on Apr. 24, 2003.
The present invention relates generally to a lock mechanism for a vehicle door latch including a superlock function.
Known latches are used to releasably secure vehicle doors in a closed position. The latch is mounted on the door and includes a retention plate having an opening which receives a striker that is typically mounted on a fixed structure of the vehicle. A latch bolt in the form of a rotatable claw having a mouth is typically pivotably mounted to the retention plate. The claw is provided with fully latched and first safety abutments against which a pawl, also pivotally mounted to the retention plate, may engage. As the door is closed, the striker enters the opening of the retention plate and the mouth of the claw, rotating the claw and engaging the pawl with one of the abutments, thereby releasably retaining the claw and maintaining the door in a closed position. Mechanical or electrical linkages are provided from the latch to handles, buttons and the like to control the operation of the latch.
Latches on different vehicles, and in particular different latches on a particular vehicle, can have different security/operating modes. Thus, a latch may be a) openable by operation of an inside door handle, b) openable by operation of an outside door handle, c) lockable by operation of an inside sill button or the like, d) lockable by operation of an outside key barrel or the like, e) lockable by operation of a remote keyless entry (RKE) device, and f) superlockable by operation of a RKE device or outside key barrel.
The state of a particular latch may include one or more of the following modes: a) unlocked, b) locked (i.e., operation of an outside door handle does not unlatch the latch, but operation of an inside door handle does unlatch the latch), c) superlocked (wherein any number of operations of an inside door handle or an outside door handle, in any order, does not unlatch the latch), and d) child safety on (wherein operation of an inside door handle does not unlatch the latch, but operation of an outside door handle may or may not unlatch the latch, depending upon whether the door is locked or unlocked).
Furthermore, a certain sequence of events can be used to perform desired functions. With a locked latched door, operation of an inside door handle may unlatch the latch and, at the same time, unlock the latch. Upon subsequent closing of the door, the door is unlocked and can then be opened by operation of the outside door handle. This is known as override unlocking and prevents vehicle keys from being locked in the vehicle. This mode of operation is also useful to provide for opening of a locked door in the child safety on mode. Even though operation of the inside door handle does not unlatch the latch, it unlocks the latch and a subsequent operation of an outside door handle enables the latch to be unlatched.
A sill button associated with certain types of latches (typically driver door latches) cannot be depressed when the door is open. This also prevents keys from being locked in the vehicle. The only ways of externally locking such a latch are to either close the door and insert a key into a key barrel to lock the latch or to operate a RKE device.
Certain other types of latches require an outside door handle to be lifted when the door is in the open position to enable the sill button to be pushed down to lock the door when the door is subsequently closed. Thus, the driver has to perform a specific sequence of events (i.e., lift the outside door handle and then depress the sill button) to lock the door. This again is aimed at preventing keys from being locked in the vehicle.
There are several modes of operation of known door locks, and the way in which these functions are performed are typically carried out by mechanisms of the door latch, as opposed to mechanisms remote from the door latch. Ultimately, whichever mechanism is used, the door will only open when the pawl is moved out of engagement from the claw. The locking, the superlocking, and the child safety modes all relate to either providing a connection between a door handle or a power actuator (e.g., an electric motor) driven under the influence of a signal received from an RKE device or door handle and the pawl to move the pawl or breaking or blocking the connection to prevent movement of the pawl.
Car door latches are typically mounted at the rear of a car door, and the car door is pivotally mounted at a front edge. Typically, an inside door handle is mounted on the inside of the door and towards the front edge, and therefore a connection needs to be provided to connect the inside door handle with the door latch. Depending on the location of the inside door handle and the nature of the connection with the latch (e.g., in some cases the nature of the connection is simply to provide the unlatching of the door, whereas in other cases the nature of the connection is to provide for unlocking and unlatching of the door), different latches require different types of connections and connection orientations to be able to actuate the door latch.
In doors fitted with a sill button or another visual status indicator to indicate the locked state of a particular latch and the changing of that locked state, superlocking latches can be used to manually manipulate the sill button or the visual status indicator to provide an indication corresponding to the particular latch being unlocked, although the latch in fact remains superlocked. This situation is undesirable since it results in uncertainty in the mind of a vehicle user as to whether the latch remains superlocked, locked or unlocked. In turn, this may result in a user pulling on an inside or outside handle with excessive force to unlatch the latch under the misconception that it is unlocked when it is not, which may cause damage to the latch or associated linkages.
The present invention seeks to overcome or at least mitigate the problems of the prior art.
The present invention provides a lock mechanism for a vehicle door latch including a lock actuator drivingly coupled to a lock link for movement of the lock link between a first position corresponding to a locked state of the latch and a second position corresponding to an unlocked state of the latch. The mechanism further includes a superlock actuator drivingly connected to a superlock link slidably mounted for movement of the superlock link between a third position corresponding to a superlocked state of the latch and a fourth position corresponding to a non-superlocked state of the latch. A fixed abutment formation and an inside lock lever are mounted such that movement of the lock link between the first and second positions may be achieved when the superlock link is in the fourth position. When the super-lock link is in the third position, the relative positions of the inside lock lever, the superlock link and the abutment formation prevents movement of the lock link between the first and second positions.
The present invention also provides a child safety mechanism for a vehicle door latch including an inside release link, a wedge block and a wedge block support. The wedge block is movable on the support between a first position, in which the inside release link is in a child safety off position and is actuable by a linkage from an inside door handle to permit a latch to be released and a second position, in which the wedging action of the wedge block places the release link in a child safety on position such that the release link is not actuable by the linkage.
Embodiments of the present invention are now described, by way of example only, with reference to the accompanying drawings in which:
a is a side view of a portion of the latch shown in
Referring to
Referring to
As shown in
A release link 46 is pivotably connected to a release link connector 45 by a pin 47. The release link connector 45 extends from a pawl lifter (not shown), which rotates about the second pivot pin 38. A second release link 48 is similarly connected. The pawl lifter and the release link connector 45 rotate together about the second pivot pin 38. The pawl lifter is biased in a direction B by a spring (not shown). Rotation of a main lock lever 44 in the direction B rotates the release link 46 and the second release link 48 counter-clockwise in a direction D about the pin 47 by the action of a cam portion 49 of the main lock lever 44 to move to a locked position.
The release link 46 and the second release link 48 are biased in a clockwise direction by a spring (not shown). When the main lock lever 44 returns to the unlocked position, the release link 46 and the second release link 48 also return to their unlocked positions.
The latch 10 further includes a child safety mechanism in the form of a slidable wedge-shaped block 50 which is supported by the retention plate 22 at the intersection between a shut face portion 22a and an inside face portion 22b. As shown in
The main lock lever 44 further includes a recess formation 54 engageable by a lock link 56 (shown in broken lines in
Referring to
The lock link 56 is rotatably mounted on a housing 60 of the latch 10 and is fixed to a quadrant 62 so that rotation of the quadrant 62 causes rotation of the lock link 56. The quadrant 62 has gear teeth on the circumferential edge that engage with a pinion gear 64. The lock link 56 and the quadrant 62 may be integrally formed together as a single piece. The pinion gear 64 is coaxially pivotally mounted with a worm wheel 66 and has a dog clutch connection 65 between the pinion gear 64 and the worm wheel 66, which enables the pinion gear 64 to rotate through slightly less than 180° without rotation of the worm wheel 66. The worm wheel 66 is in turn driven by a lock power actuator in the form of a DC electric unlocking motor 68 via a worm gear 70. The electric unlocking motor 68 is capable of driving the worm wheel 66 in both clockwise and counter-clockwise directions. A controller 25 controls operation of the electric unlocking motor 68.
In the context of the present invention, the term “power actuator” should be understood to encompass any actuator driven from a vehicle power source, such as a vehicle battery. Specifically, the term should not be understood to mean a manually operable actuator, such as a door handle, whose power source is a vehicle user.
A manual inside lock lever 72 is coaxially mounted with respect to the quadrant 62 and the lock link 56 and is fixed for rotation together with a sill button lever 74 (illustrated schematically) and provided on the opposite face of the housing 60 to that shown. Thus, manipulation of a sill button SB (illustrated schematically) may cause the manual inside lock lever 72 to rotate in a clockwise or counter-clockwise direction. The sill button SB also provides a visual indication of the lock status of the latch 10.
The manual inside lock lever 72 is substantially L-shaped and has two arms 72a and 72b. The arm 72a terminates in an angled edge 73. The manual inside lock lever 72 is not rotationally fixed with the lock link 56 or the quadrant 62. However, the extent to which manual inside lock lever 72 may rotate relative to the quadrant 62 is restricted in a clockwise direction by a stop 76 capable of abutting the arm 72b.
A radially extending trough or slot 78 is provided in the quadrant 62, and a superlock link 80 is slidably mounted in the trough or slot 78. As further shown in
The radial position of the superlock link 80 is controlled by a superlock power actuator in the form of a DC electric superlock motor 82. The controller 25 controls operation of the electric superlock motor 82. A superlock arm 84, the underside of which is shown in
An abutment formation 94 (shown in broken lines in
The second region 10b of the latch 10 further includes a child safety power actuator in the form of a DC electric motor 95 capable of driving the wedge-shaped block 50 (
In another embodiment, the second region 10b may also contain switches or other sensors 35 (illustrated schematically) capable of detecting the states of various latch components, and this information may be utilized by the controller 25 to control the latch functions.
Starting from the locked condition shown in
Starting again from the locked condition shown in
When the lock link 56 and the quadrant 62 are rotated clockwise (either due to operation of the RKE or unlocking via the key resulting in drive from the electric unlocking motor 68), the lock link 56 drives the quadrant 62, and therefore the superlock link 80, counter-clockwise and the second pin 80b contacts the abutment formation 94. In turn, this causes the superlock link 80 to move radially inwards in the trough or slot 78. Even if the manual inside lock lever 72 abuts the superlock link 80 at the start of the operation, the lost motion connection between the manual inside lock lever 72 and the quadrant 62 rotates the manual inside lock lever 72 clockwise relative to the quadrant 62 until the manual inside lock lever 72 abuts the stop 76 during counter-clockwise drive of the quadrant 62.
Thus, the wedging action between the angled edge 73, the first pin 80a, the abutment formation 94 and the second pin 80b does not occur and unlocking is not impeded. The manual inside lock lever 72 can rotate counter-clockwise and the second pin 80b is pushed further to the left by the abutment formation 94, thereby cancelling superlock. The electric superlock motor 82 is backdriven.
Changing the state of the latch 10 from unlocked to locked or superlocked is essentially the reverse of the unlocking and un-superlocking operations described above.
The lock mechanism ensures that the status of the lock as indicated by the sill button SB is always the same as the actual status of the lock mechanism 58 of the latch 10, ensuring that there is no doubt in the mind of a vehicle user as to the status of a particular latch 10 on their vehicle.
Numerous changes may be made within the scope of the present invention. For example, the mechanism may be adapted for use with manually actuable latches in which the electric superlock motor 82 may be replaced by a suitable linkage to a key barrel mounted on the exterior of a vehicle door to which the latch 10 is fitted and by dispensing the electric unlocking motor 68 and the associated gears. An alternatively arranged superlock link includes a single pin, and the locking mechanism may be adapted to be actuated in a linear, rather than rotary, manner. Alternative means of indicating the locked state of the latch and changing the status may be used in place of a sill button SB. Examples of these include buttons provided proximate to the inside handle ISH or the position of the inside handle ISH itself (e.g., pushed inwardly from a normal rest position when locked). The abutment surface may be provided on any body that is fixed relative to the lock link 56 and the superlock link 80. The superlock link 80 may be movably mounted on any suitable body that is rotationally fixed with the lock link 56.
The foregoing description is only exemplary of the principles of the invention. Many modifications and variations of the present invention are possible in light of the above teachings. The preferred embodiments of this invention have been disclosed, however, so that one of ordinary skill in the art would recognize that certain modifications would come within the scope of this invention. It is, therefore, to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described. For that reason the following claims should be studied to determine the true scope and content of this invention.
Number | Date | Country | Kind |
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0309266.5 | Apr 2003 | GB | national |
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5538298 | Ikeda | Jul 1996 | A |
5584515 | Silye | Dec 1996 | A |
5722272 | Bridgeman et al. | Mar 1998 | A |
6116664 | Wegner | Sep 2000 | A |
20020056996 | Fukunaga et al. | May 2002 | A1 |
Number | Date | Country |
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196 19 849 | Jul 1997 | DE |
Number | Date | Country | |
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20040227359 A1 | Nov 2004 | US |