EP4165271A1

EP4165271A1 - Controller for a retractable handle arrangement

Info

Publication number: EP4165271A1
Application number: EP21733914.2A
Authority: EP
Inventors: Bruno GAOUYER; Andrew Powell; Samuel GOODCHILD; Lee PIOTROWSKI
Original assignee: Jaguar Land Rover Ltd
Current assignee: Jaguar Land Rover Ltd
Priority date: 2020-06-11
Filing date: 2021-06-11
Publication date: 2023-04-19
Also published as: GB2595914B; GB202008886D0; GB2595914A; WO2021250253A1

Abstract

Aspects of the present invention relate to a controller (6) for a retractable handle arrangement (2) comprising a handle moveable between a deployed position and a stowed position. The controller comprises an input for receiving a retract trigger signal indicative of a request to trigger retraction of the handle. The controller is configured, in dependence on receiving said retract trigger signal, to output a first command signal to an actuator mechanism of the retractable handle arrangement to cause the actuator mechanism to effect retraction of the handle by means of a first force, the first force being less than a predetermined threshold. The controller comprises an input for receiving a first retraction error signal indicative of a failure of the handle to reach the stowed position. The controller is configured, in dependence on receiving said first retraction error signal, to output a second command signal to the actuator mechanism to cause the actuator mechanism to perform an assisted retraction of the handle by which a retraction force exerted on the handle exceeds the predetermined threshold.

Description

CONTROLLER FOR A RETRACTABLE HANDLE ARRANGEMENT

TECHNICAL FIELD

The present disclosure relates to a controller for a retractable handle arrangement Aspects of the invention relate to a controller, a vehicle and a method BACKGROUND

It is known to provide retractable handle arrangements wherein a handle member for use in opening a closure can be retracted such that it lies substantially flush with the surface of the closure when not in use Such retractable handle arrangements find particular use in vehicles, such as automotive vehicles, where they can be employed to improve vehicle aesthetics and reduce aerodynamic drag, for example when used as external handles for closures such as passenger doors and vehicle tailgates An example of a known retractable handle arrangement is described in UK patent publication no GB2492231 Figures 2 to 5 of GB2492231 illustrate a mechanism by which an actuator, in the form of an electric motor, is used to effect powered deployment of the handle from a stowed position to a deployed position in which it can be grasped by a user's hand in order to unlatch an associated door in which the handle arrangement is installed The actuator drives the handle member from the stowed position toward the deployed position against the force of a return spring, which biases the handle toward the stowed position In this way, retraction of the handle is effected solely by the force of the return spring acting on the handle member as the actuator is returned to an initial state associated with the stowed position of the handle

A drawback of the above described arrangement is that, under certain circumstances, the handle may not be fully retracted under the force of the return spring For example, if the vehicle has been subjected to icy and/or snowy conditions, it is possible that the handle will become stuck such that, even when the actuator is returned to its initial state, the handle remains in the deployed position

It is an aim of the present invention to address one or more of the disadvantages associated with the prior art

SUMMARY OF THE INVENTION

Aspects and embodiments of the invention provide a controller for a retractable handle arrangement, a vehicle and a method as claimed in the appended claims According to one aspect of the present invention there is provided a controller for a retractable handle arrangement comprising a handle moveable between a deployed position and a stowed position, the controller comprising; an input for receiving a retract trigger signal indicative of a request to trigger retraction of the handle, the controller being configured, in dependence on receiving said retract trigger signal, to output a first command signal to an actuator mechanism of the retractable handle arrangement to cause the actuator mechanism to effect retraction of the handle by means of a first force, the first force being less than a predetermined threshold; the controller comprising an input for receiving a first retraction error signal indicative of a failure of the handle to reach the stowed position, the controller being configured, in dependence on receiving said first retraction error signal, to output a second command signal to the actuator mechanism to cause the actuator mechanism to perform an assisted retraction of the handle by which a retraction force exerted on the handle exceeds the predetermined threshold

Thus, embodiments of the present invention provide the advantage that, in the event that a handle of a retractable handle arrangement controlled becomes stuck such that it does not fully retract following a first attempt to retract the handle (for example due to snow and/or ice in or around the handle arrangement), a retraction error can be identified and the actuator mechanism can be commanded to make a further attempt to retract the handle using a greater force than was used during the first attempt in order to increase the likelihood that the handle is freed

The controller may comprise at least one electronic processor having an electrical input for receiving the retract trigger signal and the first retraction error signal; and at least one memory device electrically coupled to the at least one electronic processor and having instructions stored therein, wherein the at least one electronic processor is configured to access the at least one memory device and execute the instructions therein so as to output the first command signal in dependence on receiving said retract trigger signal, and to output the second control signal in dependence on receiving said first retraction error signal

The controller may be configured, in dependence on receiving a further retraction error signal, to determine the time interval between receipt of the respective first and further retraction error signals and, in the event that said time interval exceeds a predetermined period, to output a signal indicative of the handle being in a stuck state

The controller may be configured, in dependence on receiving a further retraction error signal, to determine the time interval between receipt of the respective first and further retraction error signals and, in the event that said time interval exceeds a predetermined period, to cease activation of the actuator mechanism

The controller may be configured, in dependence on receiving a further retraction error signal, to determine the time interval between receipt of the respective first and further retraction error signals and, in the event that said time interval does not a predetermined period, to maintain activation of the actuator mechanism such that the retraction force exerted on the handle which exceeds the predetermined threshold is continuously applied

The controller may be configured, in dependence on receiving a further retraction error signal, to increment a counter value and compare the incremented counter value to a threshold value, the controller being configured, in the event that the incremented counter value is less than the threshold value, to output a third control signal to the actuator mechanism to cause the actuator mechanism to cease performing the assisted retraction and, subsequently to output a fourth control signal to the actuator mechanism to cause the actuator mechanism to perform a further assisted retraction of the handle

The controller may configured, in dependence on receiving a further retraction error signal, to increment a counter value and compare the incremented counter value to a threshold value, the controller being configured, in the event that the incremented counter value is not less than the threshold value, to output a third control signal to the actuator mechanism to cause the actuator mechanism to cease performing the assisted retraction

The controller may be configured, in dependence on receiving a further retraction error signal, to increment a counter value and compare the incremented counter value to a threshold value, the controller being configured, in the event that the incremented counter value is not less than the threshold value, to output a signal indicative of the handle being in a stuck state The controller may be configured, in dependence on receiving said first retraction error signal, to make a determination that there is no user risk based on one or more conditions being met

The controller may be configured to output the second command signal only if said one or more conditions are met In some embodiments, the controller may be configured to inhibit outputting of the second command signal if the one or more conditions are not met

The controller may be configured, in dependence on a determination that there is no user risk, to output the second control signal so as to cause the actuator mechanism to perform an assisted retraction of the handle by which a retraction force exerted on the handle exceeds the predetermined threshold during substantially the whole of the movement of the handle from the deployed state to the stowed state

The controller may be configured, in dependence on a determination that there is a user risk, to output the second control signal so as to cause the actuator mechanism to perform an assisted retraction of the handle by which a retraction force exerted on the handle exceeds the predetermined threshold during only an initial phase of the movement of the handle from the deployed state to the stowed state

The initial phase of movement may correspond to a handle travel of approximately 5mm or less from the deployed position

The controller may be figured to set a pulse width modulation of the second command signal in dependence on the one or more conditions being met

The one or more conditions may comprise the condition that a window associated with a door or closure in which the retractable handle arrangement is installed is in a full closed state; and the condition that the speed of a vehicle in which the retractable handle arrangement is installed exceeds a threshold vehicle speed

The one or more conditions may comprise that the condition that a user's hand is determined not to be touching or proximal to the handle

The controller may comprise an input for receiving a signal indicative of the status of a window associated with a door or closure in which the retractable handle arrangement is installed; and/or an input for receiving a signal indicative of a speed of a vehicle in which the retractable handle arrangement is installed

The controller may comprise an input for receiving a signal indicative of a user's hand touching or being proximal to the handle

According to another aspect of the invention, there is provided a vehicle comprising a controller in accordance with any one of the preceding paragraphs and at least one retractable handle arrangement

The at least retractable handle arrangement may comprise an actuator mechanism having one or more actuators, optionally wherein said one or more actuators comprises an electrical actuator, a mechanical actuator or a hydraulic actuator

According to a further aspect of the invention, there is provided a method of controlling a retractable handle arrangement comprising a handle moveable between a deployed position and a stowed position, the method comprising; receiving a retract trigger signal indicative of a request to trigger retraction of the handle; in dependence on receiving said retract trigger signal, outputting a first command signal to an actuator mechanism of the retractable handle arrangement to cause the actuator mechanism to effect retraction of the handle by means of a first force, the first force being less than a predetermined threshold; receiving a first retraction error signal indicative of a failure of the handle to reach the stowed position; and in dependence on receiving said first retraction error signal, outputting a second command signal to the actuator mechanism to cause the actuator mechanism to perform an assisted retraction of the handle by which a retraction force exerted on the handle exceeds the predetermined threshold

According to an aspect of the present invention there is provided a retractable handle arrangement for a vehicle comprising: a handle movable between a stowed position and a deployed position; and an actuator mechanism operable to: adopt a deployed state by which the actuator mechanism exerts a force on the handle or a component associated with the handle so as to move the handle from the stowed position to the deployed position; adopt a neutral state by which the handle is urged from the deployed position toward the stowed position by a first force not exceeding a predetermined threshold; and adopt an assisted retraction state in which the actuator mechanism exerts an additional force on the handle or a component associated with the handle, so as to increase the total retraction force exerted on the handle above the predetermined threshold during at least an initial phase of movement of the handle from the deployed position to the stowed position

Thus, embodiments of the present invention provide the advantage that, in the event that the handle of the arrangement becomes stuck such that it does not fully retract when the actuator mechanism adopts the neutral state (for example due to snow and/or ice in or around the handle arrangement), the actuator mechanism can adopt the assisted retraction state so as to an additional force on the handle to retract it

The retractable handle arrangement may comprise biasing means to provide the first force to urge the handle from the deployed position toward the stowed position when the actuator mechanism is in the neutral state Accordingly, in some embodiments this enables the handle to be deployed manually, without requiring movement of the actuator mechanism

The biasing means may comprise a return spring

The actuator mechanism may comprise a cam, wherein, in the deployed state, the cam abuts the handle or a component associated with the handle so as to maintain the handle in the deployed position

Embodiments of the retractable handle arrangement may comprise a retraction arm coupled to the actuator mechanism at a first end thereof and to the handle or a component associated with the handle at a second end thereof The first end of the retraction arm may be pivotally coupled to the cam at a position spaced apart from the axis of rotation of the cam Furthermore, in the assisted retraction state, the cam may be rotated such that the retraction arm exerts a force on the handle or a component associated with the handle to urge the handle toward the stowed position The retractable handle arrangement may comprise linkage means for guiding movement of the handle between the stowed and deployed positions, wherein the second end of the retraction arm is slidably connected to the linkage means Embodiments of the retractable handle arrangement may comprise a retraction arm coupled to the actuator mechanism at a first end thereof and to the return spring at a second end thereof and wherein, in the assisted retraction state, the actuator mechanism is operable to move the retraction arm so as to increase the force exerted by the return spring above the predetermined threshold The actuator mechanism may be arranged such that the cam and the retraction arm are movable independently of one another

In some embodiments, the actuator mechanism may comprise an electric motor and a clutch disposed between the electric motor and an output portion of the actuator mechanism, the clutch being operable to vary the maximum force which can be transferred from the electric motor to the output portion The retractable handle arrangement may comprise linkage means for guiding movement of the handle between the stowed and deployed positions, and comprising a retraction arm coupled to the output portion of the actuator mechanism at a first end thereof and to the linkage means at a second end thereof In the neutral state, the clutch may be partially open so as to limit the force exerted on the handle by the electric motor

In some embodiments, the predetermined threshold may be about 20N or less

The peak force exerted on the handle when the actuator mechanism adopts the assisted retraction state may be at least 120N

The actuator mechanism may be operable such that, in the assisted retraction state, the additional force exerted on the handle by the actuator mechanism is applied throughout substantially all of the travel of the handle from the deployed position to the stowed position

The actuator mechanism may comprise one or more of an electrical actuator, a mechanical actuator or a hydraulic actuator

The retractable handle arrangement may comprise means for outputting a signal indicative of a situation where the handle is not in the stowed state when the actuator mechanism has assumed the neutral state The means for outputting a signal may comprise one or more of a microswitch, a capacitive sensor, an optical sensor or a magnetic sensor

According to another aspect of the present invention, there is provided a body component for a vehicle comprising an outer panel comprising a cut out or aperture for receiving the handle of the retractable handle arrangement as described in any of the preceding paragraphs, wherein the cut out or aperture defines an edge in the panel and wherein the panel receives the handle within the cut out or aperture as a close fit and the outer surface of the handle is shaped to match the cut out or aperture and lies at least substantially flush with the outer panel when the handle is in the stowed position

According to a further aspect of the present invention, there is provided a vehicle comprising a retractable handle arrangement according to any one of the preceding paragraphs.

According to a still further aspect of the present invention, there is provided a controller for a retractable handle arrangement according to any one of the preceding paragraphs, the controller comprising an input for receiving a retract trigger signal indicative of a request to trigger a retraction of the handle arrangement, the controller being configured, in dependence on receiving said retract trigger signal, to output a command signal to the actuator mechanism of the retractable handle arrangement to cause it to adopt the assisted retraction state from the deployed state via the neutral state

The controller may comprise at least one electronic processor having an electrical input for receiving the retract trigger signal; and at least one memory device electrically coupled to the at least one electronic processor and having instructions stored therein, wherein the at least one electronic processor is configured to access the at least one memory device and execute the instructions therein so as to output the command signal in dependence on receiving said retract trigger signal According to a still further aspect of the present invention, there is provided a controller for a retractable handle arrangement according to any one of the preceding paragraphs, the controller comprising an input for receiving a retract trigger signal indicative of a request to trigger a retraction of the handle arrangement, the controller being configured, in dependence on receiving said retract trigger signal, to output a command signal to the actuator mechanism of the retractable handle arrangement to cause it to adopt the neutral state, the controller further comprising an input for receiving a signal indicative of a retraction error whereby the handle has not moved to the stowed state in response to the actuator mechanism adopting the neutral state, the controller being configured, in dependence on receiving the signal indicative of a retraction error to output a command signal to the actuator mechanism of the retractable handle arrangement to cause it to adopt the assisted retraction state

It is to be understood that the or each controller described herein can comprise a control unit or computational device having one or more electronic processors (e g , a microprocessor, a microcontroller, an application specific integrated circuit (ASIC), etc ), and may comprise a single control unit or computational device, or alternatively different functions of the or each controller may be embodied in, or hosted in, different control units or computational devices As used herein, the term “controller,” “control unit,” or “computational device” will be understood to include a single controller, control unit, or computational device, and a plurality of controllers, control units, or computational devices collectively operating to provide the required control functionality A set of instructions could be provided which, when executed, cause the controller to implement the control techniques described herein (including some or all of the functionality required for the method described herein) The set of instructions could be embedded in said one or more electronic processors of the controller; or alternatively, the set of instructions could be provided as software to be executed in the controller A first controller or control unit may be implemented in software run on one or more processors One or more other controllers or control units may be implemented in software run on one or more processors, optionally the same one or more processors as the first controller or control unit Other arrangements are also useful

Within the scope of this application it is expressly intended that the various aspects, embodiments, examples and alternatives set out in the preceding paragraphs, in the claims and/or in the following description and drawings, and in particular the individual features thereof, may be taken independently or in any combination That is, all embodiments and/or features of any embodiment can be combined in any way and/or combination, unless such features are incompatible The applicant reserves the right to change any originally filed claim or file any new claim accordingly, including the right to amend any originally filed claim to depend from and/or incorporate any feature of any other claim although not originally claimed in that manner

BRIEF DESCRIPTION OF THE DRAWINGS

One or more embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

Figure 1 is a schematic view of a vehicle comprising a retractable door handle arrangement in accordance with an embodiment of the invention;

Figures 2a, 2b and 2c show a retractable door handle arrangement of the vehicle of Figure 1 in respective stowed, deployed and operative positions;

Figure 3 is a schematic plan view of the retractable handle arrangement of Figure 2 with the handle in the stowed position; Figure 4 is a perspective view of an actuator mechanism of the retractable handle arrangement of Figure 3 in respective deployed, neutral and assisted retraction states;

Figure 5 is a schematic plan view of the retractable handle arrangement of Figure 2 with the handle in a deployed position;

Figure 6 is a schematic plan view of the retractable handle arrangement of Figure 2 with the handle in a stuck state;

Figure 7 is a schematic plan view of the retractable handle arrangement of Figure 2 with the actuator mechanism of the retractable handle arrangement in an assisted retraction state;

Figure 8 is a bottom cross-sectional view of a retractable handle arrangement according to an embodiment of the invention when installed in a vehicle;

Figure 9 is a flow diagram showing a control method for a retractable handle arrangement in accordance with an embodiment of the invention;

Figure 10 is a flow diagram showing a control method for a retractable handle arrangement in accordance with an embodiment of the invention;

Figure 11 is a flow diagram showing a control method for a retractable handle arrangement in accordance with an embodiment of the invention;

Figure 12 is a flow diagram showing a control method for a retractable handle arrangement in accordance with an embodiment of the invention;

Figure 13 is a flow diagram showing a control method for a retractable handle arrangement in accordance with an embodiment of the invention;

Figure 14 is a flow diagram showing a control method for a retractable handle arrangement in accordance with an embodiment of the invention;

Figure 15 is a schematic view of a retractable handle arrangement in accordance with another embodiment of the invention;

Figure 16a is a schematic view of a retractable handle arrangement in accordance with a further embodiment of the invention; and

Figure 16b is a schematic view of internal components of the actuator mechanism of the retractable handle arrangement shown in Figure 16a

DETAILED DESCRIPTION

Referring to Figure 1, in accordance with an embodiment of the invention, a vehicle 1 comprises a plurality of retractable handle arrangements 2 Each of the retractable handle arrangements 2 is associated with a respective door 4 of the vehicle 1 Each retractable handle arrangement 2 is operatively connected to a vehicle controller 8 For example, the controller 8 may be connected to each retractable handle arrangement 2 via a CAN bus or via a wireless network by which command signals can be sent from the controller to the retractable handle arrangements 2 and by which signals can be received therefrom as will be described in more detail later

Referring to Figures 2a, 2b and 2c, in accordance with an embodiment of the invention a retractable handle arrangement 2 comprises a handle member 8 (hereinafter, “the handle 8”) that is movable with respect to its associated door 4 when installed in a vehicle 1 The retractable handle arrangement 2 is operable to move the handle 8 between a stowed position (shown in Figure 2a), in which it lies flush with the surrounding exterior door skin 10 of its respective door 4, and a deployed position (shown in Figure 2b) When in the deployed position, or at least a partially deployed position, the handle 8 may be grasped by a user's hand and moved to an operative position (shown in Figure 2c) to release a door latch (not shown) of the associated door 4

The exterior door skin 10 of the door 4 is penetrated by a horizontally extending slot 12 that receives the handle 8 as a close fit The outer surface 14 of the handle 8 is shaped to match the slot 12 and lies flush with the surrounding door skin 10 when the handle 8 is in the stowed position The shape of the slot 12 and of the outer surface 14 of the handle 6 is chosen for aesthetic reasons and is largely immaterial in terms of function

The handle 8 is mounted to a support structure 16 or bracket of the handle arrangement 2 The support structure 16 is mounted to the door 4 such that the handle 8 is aligned with the slot 12 A sealing element, such as a rubber gasket, may be provided on the support structure 16 so as to seal around the periphery of the slot 12 when the handle arrangement 2 is mounted to the door 4 With this configuration, the ingress of water and dirt into the door cavity within which the handle arrangement 2 is mounted can be reduced

Referring to Figure 3, the handle arrangement 2 generally comprises the handle 8, a linkage means 40, which serves to guide the movement of the handle and couples the handle 8 to the support structure 16 (not shown in Figure 3 for clarity), and an actuator mechanism 60

In the present embodiment, the handle 8 is a so-called ‘strap-type' handle, which forms a loop when in the deployed position such that the handle 8 can be grasped by a user's hand with either an overhand or underhand grip The handle 8 comprises an elongate member having first and second ends 21, 22 The handle 8 has a first mounting portion 23 at the first end 21 thereof The first mounting portion 23 extends generally perpendicularly from the elongate member Similarly, the handle 8 has a second mounting portion 24 at the second end 22 thereof The second mounting portion 24 extends generally perpendicularly from the elongate member

The linkage means 40 comprises first and second link arms 42, 44 The first link arm 42 is pivotally coupled to the support structure 16 at a first end thereof so as to be rotatable about a pivot axis 46 The opposite end of the first link arm 42 is pivotally coupled to the first mounting portion 23 of the handle 8 The second link arm 44 is pivotally coupled to the support structure 16 at a first end thereof so as to be rotatable about a pivot axis 48 The opposite end of the second link arm 44 is pivotally coupled to the second mounting portion 24 of the handle 8 The linkage means 40 further comprises a coupling member 50 which is pivotally coupled at a first end 51 thereof to the first link arm 42 and at a second end 52 thereof to the second link arm 44

In the present embodiment, the handle 8 has a composite construction comprising a chassis member 26 and a cover part 28 The cover part 28 attaches to the chassis member 26 and defines the exterior surfaces of the handle 8 with which the user interacts The chassis member 26 defines the attachment points for the first and second link arms 42, 44, respectively Advantageously, this enables the same configuration of retractable handle arrangement 2 to be used for a variety of vehicle derivatives with only the need to provide a cover part 28 for the handle 8 in a particular colour to match the exterior colour of the bodywork of the vehicle 1 to which the handle arrangement 2 is installed Flowever, it will be appreciated that in alternative embodiments, the chassis member 26 and the cover part 28 could be formed as a unitary member

The actuator mechanism 60 comprises an electrical actuator 62 in the form of a rotary actuator and an actuator arm in the form of a cam 64 The cam 64 is fixedly mounted to a shaft of the electrical actuator 62 such that it rotates in dependence on a driving force applied to it by the electrical actuator 62 The actuator mechanism 60 is mounted to the support structure 16 of the handle arrangement 2 such that the cam 64 is disposed proximal to the first link arm 42 With this configuration, the electrical actuator 62 can be driven so as to rotate the cam 64 causing the cam 64 to bear against a surface of the first link arm 42, thereby causing handle 8 to move from the stowed position to the deployed position

A retraction arm 70 is pivotally coupled at a first end thereof to the cam 64 at a location which is spaced apart from the axis of the shaft of the electrical actuator 62 A second end of the retraction arm 70 comprises a pin 72 which extends substantially perpendicularly to the length of the retraction arm 20 The pin 72 locates within a slot 54 formed within the coupling member 50 With this configuration, the pin 72 can slide along the length of the slot 54 and allows the retraction arm 70 to pivot with respect to the coupling member 50

Referring to Figure 4, the cam 64 is rotatable both clockwise and counter clockwise from a neutral state, in which the cam 64 is in a generally downward orientation as it appears in Figure 4, denoted 64a Clockwise rotation of the cam 64 to the position denoted 64b corresponds to a deployed state of the actuator mechanism 60 in which the handle 8 will be moved to the deployed position Counter clockwise rotation of the cam 64 to the position denoted 64c corresponds to an assisted retraction state of the actuator mechanism 60 In the present embodiment, the working angle of the actuator mechanism 60, i e the angle of rotation between the deployed state 64b and the assisted retraction state 64c of the cam 64 is approximately 190 degrees As best shown in Figure 4, the cam 64 comprises a pin 66 to which the first end of the retraction arm 70 is pivotally attached, in use

As shown in Figure 3, under normal operating conditions, the handle 8 is in the stowed state when the cam 64 is in the neutral state 64a Deployment of the handle 8 is effected by movement of the cam 64 in a clockwise direction from the neutral state 64a to the deployed state 64b as shown in Figure 5

Referring to Figure 5, it can be seen that the cam 64 has been rotated clockwise from the neutral state 64a to the deployed state 64c As the cam 64 rotates to the deployed state, it bears against the first link arm 42 causing the first link arm 42 to pivot about the pivot axis 46 Movement of the first pivot arm 42 also causes a corresponding rotation of the second link arm 44 about its pivot axis 48 by virtue of a force being transferred from the first link arm 42 to the second link arm 46 via the coupling member 50 In this manner, rotation of the first and second link arms 42, 44 about their respective pivot axes 46, 48 causes the handle 8 to move to its deployed position (as also shown in Figure 2b) Due to the fact that the handle 8 can pivot with respect to the first and second link arms 42, 44 at the respective mounting portions 23, 24 of the handle 8, the movement of the handle 8 from the stowed position to the deployed position is substantially by translation In other words, during deployment of the handle 8, the first and second ends 21, 22 of the handle 8 move substantially in unison

In the deployed position, the pin 72 of the retraction arm 70 is spaced apart from a first end 55 of the slot 54 in the coupling member 50 This spacing allows the handle 8 to be moved to the operative position (shown in Figure 2c) by a user without the retraction arm 70 inhibiting movement of the handle 8

During normal operation of the handle arrangement 2, when it is required to move the handle 8 from the deployed position back to the stowed position, the electrical actuator 62 is operable to rotate the cam 64 in a counter clockwise direction from its deployed state 64b to the neutral state 64a Retraction of the handle 8 is effected by biasing means in the form of a return spring 80 which acts about the pivot axis 46 of the first link arm 42 so as to bias the first link arm 42 against the cam 64 Thus, as the cam 64 is moved back to the neutral state 64a, the handle 8 moves to its stowed position solely under the force applied by the return spring 80

A problem can occur when the force exerted on the first link arm 42 by the return spring 80 is not sufficient to move the handle 8 back to the stowed position For example, if the handle 8 has been deployed when the vehicle 1 is in cold conditions, it is possible that a build up of snow or ice in or around the handle arrangement 2 will prevent the handle 8 from being moved to the stowed position under the force of the return spring This situation, where the handle arrangement 2 is in a so-called stuck state, is illustrated in Figure 6

Referring to Figure 6, the cam 64 has been rotated counterclockwise from its deployed state 64b to its neutral state 64a Flowever, the handle 8 remains in the deployed position because the force applied on the first link arm 42 by the return spring 80 about the pivot axis 46 is not sufficient to move the handle 8, together with the first link arm 42, back to the stowed position It should be noted that, with the handle 8 in the stuck state, when the cam 64 is rotated to its neutral state 64a, the pin 72 of the retraction arm 70 slides within the slot 54 of the coupling member 50 Accordingly, no additional force is applied to the coupling member 50 by the retraction arm 70 when the cam 64 moves to the neutral state

Referring to Figure 7, in order to effect assisted retraction of the handle 8 to move it out of the stuck state and back to the stowed position, the electrical actuator 62 is operable to move the cam 64 counter clockwise from the neutral state 64a to an assisted retraction state 64c As the cam 64 rotates to the assisted retraction state (in the direction of arrow A), the pin 72 of the retraction arm 70 moves within the slot 54 of the coupling member 50 (in the direction of arrow B) until is abuts the first end 55 of the slot 54 at which point the retraction arm 70 exerts a force on the coupling member 50 As explained previously, a first end 51 of the coupling member 50 is attached to the first link arm 42 and a second end 52 of the coupling member 50 is attached to the second link arm 44 Accordingly, the force exerted on the coupling member 50 by the retraction arm 70 supplements the force provided by the return spring 80 and causes the first link arm to rotate clockwise about its pivot axis 467 (in the direction of arrow C) At the same time, coupling member 50 causes the second link arm 44 to rotate clockwise about its pivot axis 48 This rotation of the first and second link arms 42, 44 thus causes the handle 8 to move from the deployed position toward the stowed position

In the present embodiment, the return spring 80 may be selected such that the force exerted at the handle 8 when the handle is in the deployed position is approximately 20N Accordingly, under normal operating conditions (i e when the handle 8 is not in a stuck state), when the cam 64 moves from its deployed state 64b to its neutral state 64a, the force exerted by the return spring 80 is sufficient to retract the handle 8 and move it to the stowed position The peak force applied to the handle 8 via the return spring 80 can advantageously be selected so as to reduce the risk of any injury to a user's hand in the event that the user is holding the handle 8 during a normal, un-assisted, retraction operation In other words, the return spring 80 may be selected such that the peak force it can exert on the handle 8 at the deployed position is at or below a threshold force

In the event that the handle 8 is in a stuck state, an additional force can be exerted on the handle 8, via the first link arm 42, coupling member 50 and retraction arm 70, by rotation of the cam 64 to the assisted retraction state 64c For example, in the present embodiment, an additional force of approximately 100N may be applied to the handle 8 by the actuator mechanism 60 during an assisted retraction operation In this way, a total force of 120N is applied to the handle 8, i e the combined force of the return spring 80 and the actuator mechanism 60, so as to break any ice or snow which has built up on the handle arrangement 2 and is preventing it from returning to the stowed state under the force of the return spring 80 alone

In view of the fact that the force exerted on the handle 8 is significantly greater during the assisted retraction, the handle arrangement 2 may be configured to guard against a risk of injury to a user's hand by only applying the additional force using the actuator mechanism 60 during an initial phase of retraction of the handle 8 as will now be explained

Referring to Figure 8, the support structure 16 of the handle arrangement 2 comprises a stop member 17 disposed adjacent to the cam 64 when the cam 64 is in the assisted retraction state 64c In this way, the stop member 17 limits the rotational travel of the cam 64 such that the additional retraction force provided by the actuator mechanism 60 can only be exerted during an initial phase of the handle's 8 travel from the deployed position back to the stowed position As shown in Figure 8, when the handle arrangement 2 is installed within the vehicle door, the dimension x represents the clearance between an inner surface 15 of the handle 8 and the adjacent door skin 10 Accordingly, in order to substantially prevent or mitigate the risk of injury to a user's hand (in the event that a user is holding the handle 8 during an assisted retraction), the stop member 17 is arranged so as to limit movement of the cam 64 beyond the point at which the clearance between the inner surface 15 of the handle 8 and the surrounding door skin is a nominal safe distance In the present embodiment, the nominal safe distance is selected to be approximately 21 mm, which represents a finger width measurement equal to the 95^th percentile of people in the USA, as measured across the joint of the middle finger (third digit) nearest the palm, from the palm side to the opposite side with the finger straight In this way, application of the additional force to the handle 8 by the actuator mechanism 60 during assisted retraction of the handle is limited to a region of travel of the handle 8 where the risk of injury to a user's hand is low

In the present embodiment, the total amount of travel of the handle 8 from a fully deployed position to the stowed position, i e the distance in the x-direction between the outer surface 14 of the handle 8 and the surrounding door skin 10 when the handle is in the deployed position is approximately 40mm The stop member 17 is arranged such that the actuator mechanism 60 is operable to provide the additional assisted retraction force for the first 10mm of travel of the handle 8 from its fully deployed position toward its stowed position As shown in Figure 8, the cam 64 abuts the stop member 17 at a distance x of 21mm Thus, taking into account the thickness of the handle 8, i e the distance in the x-direction between the respective outer handle surface 14 and the inner handle surface 15 being approximately 9mm, it will be appreciated that the position of the handle 8 shown in Figure 8 represents the point at which it has been retracted by 10mm

It will generally be the case that, where the handle 8 is in a stuck state caused by a build up of ice and/or snow around the retractable handle arrangement 2, it is sufficient for the additional retraction force to be applied only during an initial phase of retraction of the handle 8, e g during the first 10mm of travel, in order to break any ice and free the handle 8 from the stuck state Thus, once the cam 64 has abutted the stop member 17, the only force which can act to retract the handle 8 for the remaining portion of its travel toward the fully stowed position is provided by the return spring 80 In other embodiments, the initial phase of movement of the handle during which the additional retraction force is applied may be approximately 5mm or less

In other embodiments, the stop member 17 may be omitted or the stop member 17 may be positioned so as to permit rotation of the cam 64 such that it an additional retraction force is exerted on the handle 8 over the entire length of travel of the handle from the deployed position to the stowed position when the actuator mechanism 60 adopts the assisted retraction state

In some embodiments, the retraction arm 70 may be formed from a material capable of elastic deformation This may be useful in preventing damage to components of the linkage means 40 or the actuator mechanism 60 in the case that the force applied by the electrical actuator during and assisted retraction would otherwise cause such but for deformation of the retraction arm 70 Alternatively or in addition, in some embodiments the current in the electrical actuator may be monitored and used to determine is there is a risk of overheating or burn out of the electrical actuator during an assisted retraction of the handle 8 when in a stuck state

Referring to Figure 9, an embodiment of a control method suitable for use by the controller 6 of the above-described embodiment to control the retractable handle arrangement 2 will now be described

At step S10, the controller 6 receives a signal indicative of a request to retract the handle 8 from the deployed position to the stowed position Such a signal will be hereinafter be referred to as a “retract trigger” A retract trigger may result from a number of events occurring For example, a retract trigger may be generated when the user locks the vehicle doors, e g by means of pressing a lock button on a wireless key fob, by pressing a button on the handle arrangement 2 itself or by pressing a button within the vehicle cabin Where the vehicle 1 is equipped with a passive entry key fob, a retract trigger may be generated when a user moves the key fob to a distance from the vehicle 1 which is greater than a threshold distance A retract trigger may also be generated in response to the vehicle 1 being driven in excess of a threshold speed, e g 5 km/hr Alternatively, a retract trigger may be generated if the handle 8 has been in the deployed state for a period of time in excess of a threshold time during which there has been no user interaction with the handle 8, i e the vehicle has been unlocked but the user has not pulled on the handle 8 to unlatch the associated vehicle door 4

In response to receiving the retract trigger at step S10, the controller 6 is configured to output a command signal to the or each retractable handle arrangement 2 associated with the vehicle 1 to cause the actuator mechanism 60 to adopt its neutral state 62a That is, the electrical actuator 62 is commanded to rotate the cam 64 to the neutral state 64a In the present embodiment, the controller 6 then commands the actuator mechanism 60 to adopt the assisted retraction state 64c at step S30 That is, the electrical actuator 62 is controlled so as to move the cam 64 until it abuts the stop member 17, thereby imparting an additional retraction force to the handle 8 during an initial phase of its travel from the deployed position to the stowed position At step S40, the controller 6 commands the actuator mechanism 60 to return to the neutral state

The control method described above with reference to Figure 9 is particularly suitable for the above-described embodiment of the handle arrangement in which the additional force exerted on the handle by the actuator adopting the assisted retraction state is only applied during the initial phase of handle movement from the deployed to the stowed state With this arrangement, the assisted retraction of the handle can be performed every time the handle 8 is retracted regardless of whether any determination has been made as to whether the handle 8 is in the stuck state or not Accordingly, although steps S20 and S30 are shown as separate method steps in Figure 9, they could be combined such that the controller 6 outputs a single command signal which causes electrical actuator 62 to move the cam 64 from the deployed state 64b to the assisted retraction state 64c via the neutral state 64b In an alternative embodiment, step S40 may be omitted such that the actuator mechanism 60 is maintained in the assisted retraction state until the controller 6 receives a subsequent request to deploy the handle 8 again

Referring to Figure 10, steps S10 and S20 are the same as described above with reference to Figure 9 Flowever, in the embodiment of Figure 10, at step S25 the controller 6 is operable to determine whether there has been a retraction error, i e whether the handle 8 is in the stuck state As described previously, under normal operating conditions, the handle 8 returns to the stowed position solely under the force exerted by the return spring 80 when the cam 64 is moved to the neutral state 64a If the handle 8 is in the stuck state, such that it remains in the deployed position when the cam 64 is in the neutral state this may be determined by means of a sensor or switch For example, the retractable handle arrangement 2 may comprise a microswitch or a sensor (such as an optical, magnetic or capacitive sensor) for use in determining whether the handle 8 has returned to the stowed position when the cam 64 is in the neutral state 64a If, at step S25, it is determined (using the switch or sensor) that the handle 8 has reached the stowed position, then it is determined that there has not been a retraction error and the method ends If, however, it is determined at step S25 that the handle 8 is not in the stowed position and that a retraction error has occurred, then the method moves on to steps S30 and S40 as described previously

With the method of Figure 10, advantageously, wear and tear on components of the retractable handle arrangement 2 may be reduced because an assisted retraction is only performed if it is determined that there has been a retraction error Flowever, this method may require additional hardware, in the form of a switch or sensor, to determine whether a retraction error has occurred

Referring to Figure 11, steps S10, S20, S25 and S30 are the same as described above with reference to Figures 9 and 10 Flowever, in the embodiment of Figure 11, after the actuator mechanism 60 has been commanded to adopt the assisted retraction state at step S30, an additional determination is made at step S35 as to whether a retraction error has occurred If, at step S35, it is determined (using the switch or sensor) that the handle 8 has reached the stowed position, then it is determined that there is no longer a retraction error and the method ends If, however, it is determined at step S35 that the handle 8 is not in the stowed position, this may indicate that the additional retraction force provided by the actuator mechanism 60 is not sufficient to move the handle 8 out of the stuck state, e g because a build up of ice on the handle arrangement is too great In this instance, the method proceeds to step S50 at which a determination is made as to whether a predetermined time period has expired If the predetermined time period has not expired, the method loops back to step S35 and another determination is made as to whether the handle 8 has been moved to the fully stowed state or whether there is still a retraction error If, at step S50, it is determined that the predetermined time period has expired then, at step S55, the controller 6 outputs an error signal The error signal may be output to a human machine interface (HMI) of the vehicle 1 in order to notify a vehicle occupant that retraction of the handle 8 is not possible and that the handle 8 remains in the stuck state At step S60, the controller 6 commands the actuator mechanism 60 to assume the neutral state 64a and the method ends

With the method of Figure 11, damage to the retractable handle arrangement 2 may be avoided in the event that the actuator mechanism 60 is not sufficiently powerful to dislodge the handle 8 from the stuck state In particular, overheating of the electrical actuator 62 can be avoided by setting the predetermined time period after which, if the handle 8 has not been successfully retracted, the actuator mechanism 60 returns to the neutral state and is de-energised, allowing it to cool

Referring to Figure 12, steps S10, S20, S25, S30 and S35 are the same as described above with reference to Figures 9, 10 and 11 Flowever, in the embodiment of Figure 12, if it is determined at step S35 that there is a still a retraction error, i e the handle 8 remains in the stuck state even after an assisted retraction has occurred then, at step S70, a counter is incremented and compared to a predetermined number n If the current counter value is less than n, the method proceeds to step S75 at which the controller 6 commands the actuator mechanism 60 to adopt the neutral state 64a From step S75, the method loops back to step S30 at which the controller 6 commands the actuator mechanism 60 to adopt the assisted retraction state in order to attempt to retract the handle 8 If, at step S70, it is determined that the current counter value is equal to the predetermined number n, then the method proceeds to step S80 where the controller 6 outputs an error signal As before, the error signal may be output to a human machine interface (HMI) of the vehicle 1 in order to notify a vehicle occupant that retraction of the handle 8 is not possible and that the handle remains in the stuck state At step S90, the controller 6 commands the actuator mechanism 60 to assume the neutral state 64a and the method ends

With the method of Figure 12, the actuator mechanism 60 can be controlled so as to apply the addition retraction force to the handle 8 in a cyclical manner The repeated application of the additional retraction force may be advantageous in breaking or dislodging ice and/or snow from the retractable handle arrangement 2 in order to return the handle 8 to the stowed position as compared to simply applying the additional retraction force continuously for a predetermined period of time as per the embodiment of Figure 11

Referring to Figure 13, steps S10, S20 and S25 are the same as described above with reference to Figures 9 and 10 However, in the embodiment of Figure 13, if it is determined at step S25 that there is a retraction error then, at step S100, a determination is made as to whether there is a risk to a user The method of Figure 13 is therefore particularly useful with embodiments of the retractable handle arrangement 2 which are capable of providing the additional retraction force throughout substantially the whole of the handle travel from the deployed state to the stowed state This may be achieved by omitting the stop member 17 or positioning the stop member 17 so as to allow for a greater degree of rotation of the cam 64 in the counter clockwise direction With this configuration, the portion of travel of the handle 8 over which the additional retraction force is applied by the actuator mechanism 60 is dependent on the extent to which the cam 64 is controlled to rotate in the counter clockwise direction past the neutral state into the assisted retraction state 64c

In the method of Figure 13, the determination of whether there is a risk to a user comprises determining whether a number of conditions are met These conditions include determining whether the vehicle 1 is moving at a speed greater than a threshold speed, e g 24 km/hr, and whether the window of the door 4 associated with the stuck handle 8 is fully closed If both of the aforesaid conditions are met, it is determined that there is no risk to a user and, at step S110, an assisted retraction to be initiated by the controller 6 is set to be a fully assisted retraction, i e such that the actuator mechanism 60 exerts an additional force on the handle 8 throughout substantially all of the handle travel from the deployed position to the stowed position If, however, at step S100, it is determined that one of more of the conditions is not met, it is determined that there is a risk to a user, e g there is a possibility that a user may be holding the handle 8 In this situation, the method proceeds instead to step S120 at which an assisted retraction to be initiated by the controller 6 is set to be a partial assisted retraction, i e such that the actuator mechanism 60 exerts an additional force on the handle 8 throughout only an initial phase of the handle travel from the deployed position to the stowed position From either step S110 or step S120, the method proceeds to step S130 at which the controller 6 outputs the relevant control command to the retractable handle arrangement 2 such that the electrical actuator rotates the cam in the counter clockwise direction from the neutral state to an appropriate position in accordance with either a fully or a partial assisted retraction being set Next, at step S140, the controller 6 commands the actuator mechanism 60 to assume the neutral state 64a and the method ends

Referring to Figure 14, steps S10, S20, S25 are and S100 the same as described above with reference to Figures 9, 10 and 13 The method of Figure 14 is suitable for use with a retractable handle arrangement having an electrical actuator which is operable to output a variable level of force (i e a variable torque in the case of a rotary actuator of the kind described above) in dependence on a pulse width modulation (PWM) control signal output from the controller 6 Thus, at step S100, if the aforementioned conditions are met, it is determined that there is no risk to a user and, at step S150 the control signal for the electrical actuator 62 of a retractable handle arrangement 2 is set as a high PWM signal If, however, at step S100, it is determined that one of more of the conditions is not met, the method proceeds to step S160 and the control signal for the electrical actuator 62 of a retractable handle arrangement 2 is set as a low PWM signal From either step S150 or step S160, the method proceeds to step S170 at which the controller 6 outputs the relevant control signal to the retractable handle arrangement 2 such that the electrical actuator 62 is driven so as to move the cam 64 to the assisted retraction state with a force in accordance with the PWM signal Subsequently, at step S180, the controller 6 commands the actuator mechanism 60 to assume the neutral state 64a and the method ends

The method of Figure 14 is particularly useful with embodiments of the retractable handle arrangement 2 where the additional force exerted by the actuator mechanism 60 during assisted retraction of the handle 8 is applied throughout substantially all of the handle travel from the deployed position to the stowed position With this configuration, the low PWM can be configured such that the additional force exerted on the handle 8 during an assisted retraction does not substantially increase the force exerted on the handle by the return spring 80 above the first threshold Accordingly, if a user is holding the handle during such an assisted retraction, there is no risk of injury

For the methods described above with reference to Figures 13 and 14, a further condition which may be used at step S 100 to determine whether there is a risk that a user may be holding the handle is the output from a capacitive sensor disposed on the handle member, e g on or proximal to the inner surface 15 of the handle 8 Such a sensor may be used to determine that a risk to a user is present, i e by detecting a change in capacitance due to the proximity of the hand of a user In other embodiments, a sensor (such as a capacitive sensor) which outputs a signal indicative of whether a user's hand is holding or proximal to the handle 8 may be used as the sole condition for determining whether there is a user risk at step S100, or in combination with further conditions

Referring to Figure 15, an alternative embodiment of a retractable handle arrangement 102 generally comprises a handle 108, a linkage means 140, which serves to guide the movement of the handle 108 and couples the handle 108 to a support structure (not shown in Figure 15 for clarity) and an actuator mechanism 160

The handle 108 comprises an elongate member having first and second ends 121, 122 The handle 108 has a first mounting portion 123 at the first end 121 thereof The first mounting portion 123 extends generally perpendicularly from the elongate member Similarly, the handle 108 has a second mounting portion 124 at the second end 122 thereof The second mounting portion 124 extends generally perpendicularly from the elongate member The linkage means 140 comprises first and second link arms 142, 144 The first link arm 142 is pivotally coupled to the support structure at a first end thereof so as to be rotatable about a pivot axis 146 The opposite end of the first link arm 142 is pivotally coupled to the first mounting portion 123 of the handle 108 The second link arm 144 is pivotally coupled to the support structure at a first end thereof so as to be rotatable about a pivot axis 148 The opposite end of the second link arm 144 is pivotally coupled to the second mounting portion 124 of the handle 108 The linkage means 140 further comprises a coupling member 150 which is pivotally coupled at a first end 151 thereof to the first link arm 142 and at a second end 152 thereof to the second link arm 144

The actuator mechanism 160 comprises an electrical actuator 162 in the form of a rotary actuator The electrical actuator 162 has a primary output shaft to which an actuator arm in the form of a cam 164 is mounted The cam 164 is fixedly mounted to the primary output shaft of the electrical actuator 162 such that it rotates in dependence on a driving force applied to it by the electrical actuator 162 The actuator mechanism 60 is mounted to the support structure of the handle arrangement 102 such that the cam 164 is disposed proximal to the first link arm 142 With this configuration, the electrical actuator 162 can be driven so as to rotate the cam 164 causing the cam 164 to bear against a surface of the first link arm 142, thereby causing handle 8 to move from the stowed position to the deployed position

The electrical actuator 162 further comprises a secondary output shaft, the rotational axis of which is laterally spaced apart from the rotational axis of the primary output shaft A retraction arm 170 is fixedly coupled to the secondary output shaft of the electrical actuator 162 at a first end thereof A second end of the retraction arm 170 comprises a pin 172 A return spring 180 is attached to the pin 172 of the retraction arm 170 at a first end thereof A second end of the return spring 180 is attached to a pin 149 provided on the first link arm 142 The pin 149 on the first link arm 144 is spaced apart from the pivot axis 146

I n the present embodiment, the electrical actuator 162 is provided as a single integrated actuator having primary and second output shafts which are independently controllable It will be appreciated that the electrical actuator 162 could alternatively be provided as a pair of rotary actuators having respective output shaft mounted in the appropriate positions relative to on another

Operation of the retractable handle arrangement 102 described above with reference to Figure 15 will now be described As shown in Figure 15, the handle 108 is in a deployed position such that is projects beyond the surface of the adjacent door skin 110 to be grasped by a user's hand Accordingly, Figure 15 shows the actuator mechanism 160 in a deployed state in which the cam 164 abuts the first link arm 142 so as to maintain it in the deployed position against the force exerted on the first link arm 142 by the return spring 180 at the pin 149

When it is required to retract the handle 108, the electrical actuator 162 is operable to rotate the cam 164 in a clockwise direction indicated by arrow D in Figure 15 As the cam 164 rotates, the first link arm 142 is pulled by the return spring 180 (which is a tension spring in the present embodiment) and rotates clockwise around its pivot axis 146 until the handle is in the stowed state In the present embodiment, a neutral state of the actuator mechanism 160 is therefore defined by the cam 164 being rotated in the direction D until the point at which the handle 108 is fully stowed under normal operation conditions, i e when the handle 108 is not in a stuck state

In the present embodiment, the cam 164 and the first link arm 142 can move independently of one another Accordingly, in the event that the handle 108 is stuck in the deployed position, i e due to a build up of ice and/or snow in or around the retractable handle arrangement 102, the handle 108 will remain in the deployed position after the cam 164 has been rotated to the neutral state in the event that the force exerted by the return spring 180 is not sufficient to retract it In this situation, the actuator mechanism is operable to increase the force exerted by the return spring 180 and provide an assisted retraction Assisted retraction is achieved by controlling the electrical actuator 162 to rotate the retraction arm 170 in a counterclockwise direction as indicated by arrow E in Figure 15 This movement of the retraction arm 170 increases the distance between the respective ends of the return spring 180, i e the separation between the pin 149 and the pin 172 increases in the direction of the arrow F Accordingly, this increases the tension in the return spring 180 which, in turn, increases the retraction force being exerted by the return spring 180 on the first link arm 144 and thus on the handle 108

Advantageously, with the above arrangement, the return spring 180 can be selected such that the maximum force it exerts on the handle 108 when the actuator mechanism 160 is in the neutral state does not exceed a predetermined threshold force The threshold force can be selected so as to be a force which would not risk causing injury to a user's hand in the event that a user is holding the handle 108 during retraction of the handle 108 under normal operating conditions In the case that the handle 108 is in a stuck state, the force on the handle 108 can be increased above the threshold force by virtue of the actuator mechanism 160 adopting the assisted retraction state in which the retraction arm 170 is moved so as to increase the force on the return spring 180

Referring to Figures 16a and 16b, an alternative embodiment of a retractable handle arrangement 202 generally comprises a handle 208, a linkage means 240, which serves to guide the movement of the handle and couples the handle 208 to a support structure (not shown in Figure 16a for clarity) and an actuator mechanism 260

The handle 208 comprises an elongate member having first and second ends 221, 222 The handle has a first mounting portion 223 at the first end 221 thereof The first mounting portion 223 extends generally perpendicularly from the elongate member Similarly, the handle 208 has a second mounting portion 224 at the second end 222 thereof The second mounting portion 224 extends generally perpendicularly from the elongate member

The linkage means 240 comprises first and second link arms 242, 244 The first link arm 242 is pivotally coupled to the support structure at a first end thereof so as to be rotatable about a pivot axis 246 The opposite end of the first link arm 242 is pivotally coupled to the first mounting portion 223 of the handle 208 The second link arm 244 is pivotally coupled to the support structure at a first end thereof so as to be rotatable about a pivot axis 248 The opposite end of the second link arm 244 is pivotally coupled to the second mounting portion 224 of the handle 208 The linkage means 240 further comprises a coupling member 250 which is pivotally coupled at a first end 251 thereof to the first link arm 242 and at a second end 252 thereof to the second link arm 244

The actuator mechanism 260 comprises a first electrical actuator in the form of a drive motor 262 and a second electrical actuator in the form of a clutch motor 264 The drive motor 262 has a first gear 263 mounted to an output shaft thereof The first gear 263 is arranged so as to mesh with a second gear 265 which is mounted co-axial with the clutch motor 264 A clutch 266 is mounted co-axial with the second gear 265 between the second gear 265 and an output portion 268 of the actuator mechanism 260

The actuator mechanism 260 is mounted to the support structure of the handle arrangement 202 proximal to the first link arm 242 A retraction arm 270 is fixedly coupled at a first end thereof to the output portion 268 of the actuator mechanism 260 A second end of the retraction arm 270 is pivotally coupled to the first link arm 242 The retraction arm 270 is an articulated arm having a pivot point approximately mid way along its length In the present embodiment, the second end of the retraction arm 270 couples to the first link arm 242 proximal to the first end of the coupling member 250 In one embodiment, the second end of the retraction arm 270 and the first end of the coupling member 251 share a common attachment point to the first link arm 242

With this configuration, the actuator mechanism 260 is operable to deploy and retract the handle 208 In more detail, the clutch motor 264 is operable to open and close the clutch 266 so as to vary the amount of torque that is transmitted from the drive motor 262, through the first and second gears 263 265 to the output portion 268 of the actuator mechanism Accordingly, the clutch 266 can be used to limit the force which can be transferred to a user's hand during deployment and retraction of the handle 208

As shown in Figure 16a, the handle 208 is in a deployed position This corresponds to a deployed state of the actuator mechanism 260 in which the retraction arm 270 has been rotated to a position in which it pushes on the first link arm 242 so as to deploy the handle 208 Accordingly, in the present embodiment, the retraction arm 270 also serves as an actuator arm to deploy the handle 8 The actuator mechanism 260 may comprise a non-reversible gearbox such that the actuator mechanism 260 holds the handle 208 in the deployed position and cannot be back driven if a user pushes on the outer surface 214 of the handle 208 To retract the handle 208, the drive motor 262 is operable to rotate the output portion 268 of the actuator mechanism 260, e g in a clockwise direction, which causes the retraction arm 270 to exert a retraction force on the first link arm 242 and thus on the handle 208 Rotation of the output portion 268 of the actuator mechanism 260 continues until the handle 208 is in the stowed position In the presently described embodiment, a neutral state of the actuator mechanism 260 corresponds to a state in which the drive motor 262 of the actuator mechanism is driven from its position in the deployed state to a position in which handle is in the stowed state (i e when the handle 208 is not in a stuck state) while the clutch 266 is partially open so as to limit the force which is transferred from the drive motor 262 to the retraction arm 270, and thus to the handle 208

In the embodiment of Figure 16a and 16b, the retraction arm 270 and the first link arm 242 are mechanically coupled so that they cannot move independently of one another Accordingly, in the event that the handle 208 is stuck in the deployed position, i e due to a build up of ice and/or snow in or around the retractable handle arrangement 202, the handle 208, first link arm 242 and retraction arm 270 will all remain in the same position as the drive motor 262 is driven to the neutral state In this situation there will be slip across the clutch 266 in the event that the maximum force which can be transferred across the clutch 266 when it is in the neutral, partially open, state is not sufficient to retract the handle 208

The actuator mechanism 260 is operable to increase the force exerted on the handle 208 and provide an assisted retraction Assisted retraction is achieved by controlling the clutch motor 264 to close the clutch 266 such that a greater force can be transferred from the drive motor 262 to the output portion 268 of the actuator mechanism 260 In this assisted retraction state, the clutch 266 may be fully closed, or simply more closed than it is in the neutral state Accordingly, rotation of the output portion 268 of the actuator mechanism in this state serves to exert an increased retraction force on the handle 208

Advantageously, with the above arrangement, the force which can be exerted on the handle 208 when the actuator mechanism 160 is in the neutral state does not exceed a predetermined threshold force The predetermined threshold force can be selected so as to be a force which would not risk causing injury to a user's hand in the event that a user is holding the handle 208 during retraction of the handle under normal operating conditions In the case that the handle 208 is in a stuck state, the force on the handle 208 can be increased above the threshold force by virtue of the actuator mechanism 260 adopting the assisted retraction state in which the clutch 266 is closed as the drive motor 262 is driven so as to transfer more force to the retraction arm 270

It will be appreciated that, with the embodiment described with reference to Figures 16a and 16b, the clutch 266 can be controlled such that the additional retraction force is only applied during an initial phase of travel of the handle 208 from the deployed to the stowed position, i e by transitioning the clutch from a closed to a partially open state during retraction of the handle 208

It will be appreciated that various changes and modifications can be made to the present invention without departing from the scope of the present application

Claims

1 A controller for a retractable handle arrangement comprising a handle moveable between a deployed position and a stowed position, the controller comprising; an input for receiving a retract trigger signal indicative of a request to trigger retraction of the handle, the controller being configured, in dependence on receiving said retract trigger signal, to output a first command signal to an actuator mechanism of the retractable handle arrangement to cause the actuator mechanism to effect retraction of the handle by means of a first force, the first force being less than a predetermined threshold; the controller comprising an input for receiving a first retraction error signal indicative of a failure of the handle to reach the stowed position, the controller being configured, in dependence on receiving said first retraction error signal, to output a second command signal to the actuator mechanism to cause the actuator mechanism to perform an assisted retraction of the handle by which a retraction force exerted on the handle exceeds the predetermined threshold

2 A controller according to claim 1, wherein the controller is configured, in dependence on receiving a further retraction error signal, to determine the time interval between receipt of the respective first and further retraction error signals and, in the event that said time interval exceeds a predetermined period, to output a signal indicative of the handle being in a stuck state; optionally, the controller is configured, in dependence on receiving a further retraction error signal, to determine the time interval between receipt of the respective first and further retraction error signals and, in the event that said time interval exceeds a predetermined period, to cease activation of the actuator mechanism

3 A controller according to any preceding claim, wherein the controller is configured, in dependence on receiving a further retraction error signal, to determine the time interval between receipt of the respective first and further retraction error signals and, in the event that said time interval does not a predetermined period, to maintain activation of the actuator mechanism such that the retraction force exerted on the handle which exceeds the predetermined threshold is continuously applied

4 A controller according to claim 1 , wherein the controller is configured, in dependence on receiving a further retraction error signal, to increment a counter value and compare the incremented counter value to a threshold value, the controller being configured, in the event that the incremented counter value is less than the threshold value, to output a third control signal to the actuator mechanism to cause the actuator mechanism to cease performing the assisted retraction and, subsequently to output a fourth control signal to the actuator mechanism to cause the actuator mechanism to perform a further assisted retraction of the handle

5 A controller according to claim 1 or claim 4, wherein the controller is configured, in dependence on receiving a further retraction error signal, to increment a countervalue and compare the incremented countervalue to a threshold value, the controller being configured, in the event that the incremented counter value is not less than the threshold value, to output a third control signal to the actuator mechanism to cause the actuator mechanism to cease performing the assisted retraction

6 A controller according to claim 1, claim 4 or claim 5, wherein the controller is configured, in dependence on receiving a further retraction error signal, to increment a counter value and compare the incremented counter value to a threshold value, the controller being configured, in the event that the incremented counter value is not less than the threshold value, to output a signal indicative of the handle being in a stuck state 7 A controller according to any preceding claim, wherein the controller is configured, in dependence on receiving said first retraction error signal, to make a determination that there is no user risk based on one or more conditions being met

8 A controller according to claim 8 or claim 9 wherein the controller is configured to output the second command signal only if said one or more conditions are met; optionally, the controller is configured, in dependence on a determination that there is no user risk, to output the second control signal so as to cause the actuator mechanism to perform an assisted retraction of the handle by which a retraction force exerted on the handle exceeds the predetermined threshold during substantially the whole of the movement of the handle from the deployed state to the stowed state

9 A controller according to claim 7 or claim 8, wherein the controller is configured, in dependence on a determination that there is a user risk, to output the second control signal so as to cause the actuator mechanism to perform an assisted retraction of the handle by which a retraction force exerted on the handle exceeds the predetermined threshold during only an initial phase of the movement of the handle from the deployed state to the stowed state; optionally, the initial phase of movement corresponds to a handle travel of approximately 5mm or less from the deployed position

10 A controller according to claim 7 or claim 8, wherein the controller is figured to set a pulse width modulation of the second command signal in dependence on the one or more conditions being met

11 A controller according to any one of claims 7 to 10, wherein said one or more conditions comprise the condition that a window associated with a door or closure in which the retractable handle arrangement is installed is in a full closed state; and the condition that the speed of a vehicle in which the retractable handle arrangement is installed exceeds a threshold vehicle speed

12 A controller according to any one of claims 7 to 11, wherein said one or more conditions comprises that the condition that a user's hand determined not to be touching or proximal to the handle

13 A controller according to any preceding claim, the controller comprising an input for receiving a signal indicative of the status of a window associated with a door or closure in which the retractable handle arrangement is installed; and/or an input for receiving a signal indicative of a speed of a vehicle in which the retractable handle arrangement is installed

14 A vehicle comprising a controller according to any one of the preceding claims and at least one retractable handle arrangement

15 A method of controlling a retractable handle arrangement comprising a handle moveable between a deployed position and a stowed position, the method comprising; receiving a retract trigger signal indicative of a request to trigger retraction of the handle; in dependence on receiving said retract trigger signal, outputting a first command signal to an actuator mechanism of the retractable handle arrangement to cause the actuator mechanism to effect retraction of the handle by means of a first force, the first force being less than a predetermined threshold; receiving a first retraction error signal indicative of a failure of the handle to reach the stowed position; and in dependence on receiving said first retraction error signal, outputting a second command signal to the actuator mechanism to cause the actuator mechanism to perform an assisted retraction of the handle by which a retraction force exerted on the handle exceeds the predetermined threshold