Abstract:
A retractable handle arrangement comprises a handle movable between stowed and deployed states, a motor and transmission means arranged to couple the motor to the handle for moving the handle from the stowed state to the deployed state when the motor is driven in a first direction, and to modulate the force exerted on the handle and the speed at which the handle is deployed as the handle travels from the stowed state to the deployed state.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to a retractable handle arrangement for a door or other closure, and a method of deploying a retractable door handle arrangement. Aspects of the invention relate to a handle arrangement, to a body component, to a method and to a vehicle. 
       BACKGROUND 
       [0002]    The invention will be described in the context of a car door but it can be used with other closures on a vehicle, such as a tailgate, or with other types of vehicle, such as aircraft. Indeed, in a broad sense, the retractable handle arrangement of the invention can be used in non-vehicular applications. 
         [0003]    The demands of aesthetics, aerodynamics and wind-noise control often make it desirable for a door handle to lie flush with the surrounding door skin of a vehicle. Flap-type door handles may be used for this reason. Such handles comprise a typically top-pivoted flap that is pulled against spring bias and hence pivoted outwardly with respect to the surrounding door skin to unlatch the door. A finger recess is usually provided in the door skin adjacent to, most commonly underneath, the flap of the handle. This recess gives finger access to the rear of the handle so that the handle may be pulled to unlatch and open the door. 
         [0004]    A flap-type handle tends to be awkward to use and cannot be grasped as comfortably or satisfyingly as other handle types. Perhaps the most convenient handle type has a protruding bar-like grab or handgrip that may be gripped in the user&#39;s hand, an example being a strap-type handle in which the handgrip is part of a loop. 
         [0005]    Strap-type handles have particular benefits over flap-type handles in terms of ergonomics and load transferral: for example, when using a flap-type handle, it is not possible for the user to choose whether to use an overhand or underhand grip style. Also, a flap-type handle constrains where the handle may be positioned on the vehicle with respect to the user&#39;s stance. Unfortunately, however, the protruding handgrip of a strap-type handle does not have the benefits of flush mounting. 
         [0006]    A flap-type handle with its associated finger recess is also an aesthetic constraint. There have therefore been several proposals in the prior art to provide a finger recess with a hinged cover plate that lies flush with the door skin and with the adjacent flap-type handle but that pivots inwardly to admit the user&#39;s fingers to operate the handle. However, this cover plate does not solve the inherent problems of a flap-type handle: if anything, it makes the handle more difficult to use. Also, arguably, a cover plate may look no better than leaving the finger recess uncovered. 
         [0007]    To solve some of these problems and to offer a ‘surprise and delight’ feature, some flush-mounted door handles are retractably mounted to a vehicle. This means that the handle can move between two states: a stowed or retracted state in which the handle is flush-mounted and a deployed or extended state in which the handle stands proud of the surrounding bodywork to be easier to grasp. Movement of the handle between the stowed and deployed states may be effected by means of an automated mechanism. 
         [0008]    Once in the deployed state, the handle can then be pulled to open the door. This involves moving the handle to a third, operative state to unlatch the door, typically by pivoting the deployed handle against spring bias. In moving from the deployed state to the operative state, the handle may unlatch the door mechanically, for example by pulling a Bowden cable acting on the door latch, or electrically, for example by switching a solenoid acting on the door latch. 
         [0009]    A problem with a retractable door handle of the kind described above exists where an automated mechanism is used to retract the door handle from the deployed state to the stowed state. In this case, there is a danger that a user&#39;s fingers may become trapped between the handle and the surrounding door skin in the case that the user is holding the handle as it retracts. 
         [0010]    Moreover, a retractable door handle of the kind described above may be susceptible to damage in the case of abuse by a user. Such damage may occur in the event that a user tries to force the door handle from the deployed state into the stowed state thereby applying stresses which could damage the mechanism. 
         [0011]    Furthermore, another problem associated with a retractable handle arrangement is to provide the user with the associated functionality, such as means to lock and unlock the door, in a way which is intuitive and simple to use. 
         [0012]    It is an object of the present invention to provide an improved retractable handle arrangement. 
       SUMMARY 
       [0013]    Aspects of the invention relate to a handle arrangement, to a body component, to a method and to a vehicle as claimed in the appended claims. 
         [0014]    According to an aspect of the present invention there is provided a retractable handle arrangement comprising:
       a handle adapted and arranged to be mounted flush within a panel, the handle being movable between stowed and deployed states;   a motor: and
 
a transmission device arranged to couple the motor to the handle for moving the handle from the stowed state to the deployed state when the motor is driven in a first direction,
   wherein, at least in the initial phase of deployment of the handle, the handle arrangement is arranged to provide a force to deploy the handle which is greater than a predetermined force.       
 
         [0018]    The applicant has recognized that a problem exists with retractable door handles in that the handle must be in the deployed state before a user can grasp the handle to open the door. In wet and freezing conditions the door handle arrangement may become iced-up. Thus, in the case that the deployment of the handle is effected by means of an automated mechanism ice may prevent the handle from deploying, leaving the user no way of opening the door until the door handle has been de-iced, which is inconvenient and time-consuming. The applicant therefore has recognized the need for a door handle arrangement in which the force used in at least an initial phase of deployment is above a predetermined level, i.e. above a level needed to break any ice which has accumulated between the handle and any surrounding features so that the handle can be moved. 
         [0019]    According to another aspect of the present invention, there is provided a retractable handle arrangement comprising:
       a handle adapted and arranged to be mounted flush within a panel, the handle being movable between stowed and deployed states;   a motor; and   a transmission device arranged to couple the motor to the handle for moving the handle from the stowed state to the deployed state when the motor is driven in a first direction, and to modulate the force exerted on the handle and the speed at which the handle is deployed as the handle travels from the stowed state to the deployed state.       
 
         [0023]    Thus, the present invention provides a retractable handle arrangement in which control of the force exerted on the handle and the speed at which the handle is deployed is controlled by the configuration of the transmission device and does not require variable control of the motor. 
         [0024]    In an embodiment, the transmission device is configured such that a greater force is exerted on the handle during an initial deployment phase than during a second, subsequent deployment phase. 
         [0025]    Accordingly, an initial force exerted on the handle can be selected so as to be sufficient to break through any ice on or in the handle arrangement and, once the handle has been moved from the stowed state, the force can be reduced accordingly. 
         [0026]    Advantageously, the transmission device may be configured such that the speed of travel of the handle is greater during the second deployment phase than during the initial deployment phase. Thus, the deployment time of the handle can be optimised so that a user does not have to wait for a long time for the handle to reach the deployed state. 
         [0027]    The transmission means may be configured such that the handle is gradually brought to a stop in the deployed state during a third deployment phase. Thus, the handle can be brought to a gradual stop so as to provide a refined and elegant appearance. 
         [0028]    In an embodiment, in use, the motor is driven at a constant speed as the handle travels from the stowed state to the deployed state. 
         [0029]    In an embodiment, the handle comprises an operating member and the transmission means comprises:
       a worm gear disposed on an output shaft of the motor;   a gear wheel arranged in meshed engagement with the worm gear rotatable about an axis;   an eccentric cam mounted coaxially with the gear wheel; and   a rocker arm having a first end in abutting, frictional engagement with the cam and a second end in abutting, frictional engagement with the operating member, the rocker arm being pivotable about an axis disposed between the first and second ends. Optionally, the cam is an eccentric cam.       
 
         [0034]    In another embodiment, the handle comprises an operating member and the transmission means comprises:
       a cam mounted coaxially with the gear wheel; and   a rocker arm having a first end in abutting, frictional engagement with the cam and a second end in abutting, frictional engagement with the operating member, the rocker arm being pivotable about an axis disposed between the first and second ends. Optionally, the cam is an eccentric cam.       
 
         [0037]    In some embodiments, the shape and/or profile of the cam is configured and/or arranged to characterise the force and/or speed with which the handle is deployed according a predefined cycle. Optionally, the cam is an eccentric cam. 
         [0038]    Optionally, the force and the speed with which the handle is deployed can be modulated or controlled independently. 
         [0039]    Optionally, the handle comprises an operating member and the transmission means comprises:
       a gear disposed on an output shaft of the motor;   a gear wheel arranged in meshed engagement with the worm gear rotatable about an axis. Optionally, the gear is a worm gear.       
 
         [0042]    In an embodiment, the handle is pivotable about an axis such that it rotates about the axis when it is moved from the stowed state to the deployed state. 
         [0043]    In an embodiment, the retractable handle arrangement comprises a return spring arranged so as to bias the handle toward the stowed state. 
         [0044]    According to another aspect of the present invention, there is provided a body component for a vehicle comprising a panel having an outer surface having an aperture for receiving the handle of the retractable handle arrangement described hereinabove wherein the aperture receives the handle as a close fit and the outer surface of the handle is shaped to match and lies flush with the outer panel when the handle is in a stowed condition. 
         [0045]    In some embodiments, the axis about which the handle rotates is arranged such that a first portion of the handle is pivoted internally of the panel and a second portion of the handle is pivoted externally of the panel. 
         [0046]    Optionally, the handle is manually operable by engaging the first portion so as to provide access to the second portion. 
         [0047]    A flexible sealing member may be provided between the handle and the aperture in the panel. 
         [0048]    According to a further aspect of the present invention, there is provided a method of deploying a motor-driven retractable handle arrangement comprising a handle movable between stowed and deployed states via a transmission means arranged to couple the motor to the handle for moving the handle from the stowed state to the deployed state when the motor is driven in a first direction, the method comprising exerting a greater force on the handle during an initial deployment phase than during a second, subsequent deployment phase and/or moving the handle at a greater speed during the second deployment phase than during the initial deployment phase. 
         [0049]    Advantageously, the method comprises bringing the handle to a gradual stop in the deployed state during a third deployment phase. 
         [0050]    According to another aspect of the present invention, there is provided a retractable handle arrangement comprising:
       a handle adapted and arranged to be mounted flush within a panel, the handle being movable between stowed and deployed states, and arranged such that it can be maintained in a deployed position;   the handle comprising an elongate element behind which a user can place their fingers to pull the handle, the handle further comprising a top cover portion extending from the top of the elongate element, the cover portion being arranged, when the handle is in the deployed state, to substantially close the gap between the handle and the panel, the handle further comprising an end cover portion, arranged to cover, in the deployed state, at least a portion of the end of the elongate element which in use is deployed out from the panel.       
 
         [0053]    Preferably the cover portion is a top cover portion, extending substantially from the top of the elongate element. 
         [0054]    The applicant has recognised that, if the handle is to be left in a deployed state, it would be advantageous for a cover portion as described above to prevent items, such as clothing, bag straps, etc. from becoming looped over the handle. In addition, when the user grips the handle in an underhand grip, the end cover portion helps to prevent the user&#39;s fingers from slipping off the end of the handle. The top cover portion and end cover portion may form a continuous cover portion. The end portion may extend over the entire end of the elongate element. The end of the elongate element may be curved. 
         [0055]    Within the scope of this application it is envisaged that the various aspects, embodiments, examples and alternatives, and in particular the features thereof, set out in the preceding paragraphs, in the claims and/or in the following description and drawings, may be taken independently or in any combination thereof. For example, features described in connection with one embodiment are applicable to all embodiments, unless such features are incompatible. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0056]    Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: 
           [0057]      FIG. 1  is a perspective view of the exterior of a vehicle door fitted with a door handle arrangement in accordance with an embodiment of the present invention, the door handle being shown in a stowed state; 
           [0058]      FIGS. 2A and 2B  are perspective views showing respective opposite sides of the mechanism of the door handle arrangement of  FIG. 1 , with the door handle in the stowed state; 
           [0059]      FIGS. 3A and 3B  are perspective views showing respective opposite sides of the mechanism of the door handle arrangement of  FIG. 1 , with the door handle in a deployed state; 
           [0060]      FIGS. 4A ,  4 B and  4 C are respective side, front and top plan views of the mechanism of the door handle arrangement of  FIG. 1 , with the door handle in the stowed state; 
           [0061]      FIGS. 5A ,  5 B and  5 C are respective side, front and top plan views of the mechanism of the door handle arrangement of  FIG. 1 , with the door handle in the deployed state; 
           [0062]      FIG. 6  shows the positions of an unlock and a lock button on the handle of the retractable handle arrangement of  FIG. 1 ; 
           [0063]      FIG. 7  shows an embodiment of a system for controlling the operation of the retractable handle arrangement of  FIG. 1 ; and 
           [0064]      FIGS. 8A ,  8 B and  8 C are perspective views of an alternative embodiment of a handle for use in the retractable handle arrangement of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
       [0065]    Detailed descriptions of specific embodiments of a handle arrangement, a method and a vehicle of the present invention are disclosed herein. It will be understood that the disclosed embodiments are merely examples of the way in which certain aspects of the invention can be implemented and do not represent an exhaustive list of all of the ways the invention may be embodied. Indeed, it will be understood that the handle arrangement, method and the vehicle described herein may be embodied in various and alternative forms. The figures are not necessarily to scale and some features may be exaggerated or minimised to show details of particular components. Well-known components, materials or methods are not necessarily described in great detail in order to avoid obscuring the present disclosure. Any specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the invention. 
         [0066]    Referring to  FIG. 1 , in a door handle arrangement  1  of one embodiment of the invention, a flush-mounted door handle  10  is retractable with respect to a door of a vehicle. A painted door skin  12  is shown here to represent the door. 
         [0067]    The door skin  12  is penetrated by a horizontally-extending slot  14  that receives the handle  10  as a close fit. The outer surface  16  of the handle  10  is shaped to match the slot  14  and lies flush with the surrounding door skin  12  when the handle  10  is stowed as shown in  FIG. 1 . The shape of the slot  14  and of the outer surface  16  of the handle  10  is chosen for aesthetic reasons and is largely immaterial in terms of function. 
         [0068]    Whilst shown in a contrasting tone for clarity in the drawings, at least the outer surface  16  of the handle  10 , and possibly the entire handle  10 , is painted in the same colour as the vehicle body. Other finishes may, of course, be chosen instead, again for aesthetic reasons. 
         [0069]    Referring to  FIGS. 2A and 2B , the retractable handle arrangement  1  comprises a mechanism  18  which is operable to move the handle  10  between the stowed state and a deployed state, as will be described in more detail later. 
         [0070]    The handle  10  is an elongate member having first and second ends  20 ,  22 . Pivot means  24  are disposed proximate to the first end  20  and define an axis about which the handle  10  is rotatable, when it moves between the stowed and deployed states. A return spring  26  is provided on the pivot means  24  so as to bias the handle  10  toward the stowed position. An operating member  28  projects perpendicularly from an inner surface  17  of the handle  10 , which is opposite the outer surface  16 . The operating member  28  is disposed at substantially the same distance along the length of the handle  10  from the first end  20  as the pivot means  24 . 
         [0071]    The mechanism  18  comprises a motor  30  which is coupled to transmission means  32 . The transmission means  32  comprises a worm gear  34 , a gear wheel  36 , a cam  38  and a rocker arm  40 . In more detail, the worm gear  34  is disposed on an output shaft  31  of the motor  30  and is coaxial therewith. The gear wheel  36  is disposed adjacent to the worm gear  34  for meshed engagement therewith. 
         [0072]    The gear wheel  36  is mounted so as to be rotatable about an axis  42  which is perpendicular to the axis of rotation of the worm gear  34 . The cam  38  is disposed adjacent to the gear wheel  36  and mounted such that the cam  38  also rotates about the axis  42  when the gear wheel  36  rotates. 
         [0073]    The rocker arm  40  has first and second ends  44 ,  46  and is pivotally mounted about a rocker axis  48  which is parallel to the axis  42  of the gear wheel  36  and the cam  38 . The rocker axis  48  is disposed toward the second end  46  of the rocker arm  40 . The first end  44  of the rocker arm  40  abuts the surface of the cam  38 . The second end  46  of the rocker arm  40  abuts the operating member  28  of the handle  10 . 
         [0074]    In the stowed state illustrated in  FIG. 1 , the outer surface  16  of the handle  10  lies flush with the surrounding door skin  12 . The handle  10  may be driven from its stowed state to its deployed state in response to various events. For example, this movement may be in response to an unlocking signal from a key authorised to unlock the vehicle or from a presence sensor that detects the presence of an authorised key in the immediate vicinity of the vehicle. Conversely, the handle  10  may be driven from its deployed state to its stowed state in response to a locking signal from a key authorised to lock the vehicle or from a presence sensor that determines that the authorised key has left the immediate vicinity of the vehicle. The handle  10  may also toggle between the stowed and deployed states in response to a further action from the user, for example pressing a switch (not shown in  FIG. 1 ) on the vehicle door. 
         [0075]    Referring to  FIGS. 3A and 3B , in its deployed state, the handle  10  is rotated about the pivot means  24  against the biasing force of the return spring  26  such that the second end  22  of the handle protrudes from the slot  14  (not shown in  FIGS. 3A and 3B ) by an amount sufficient to allow a user to put their fingers around the handle  10 . In the embodiment of the invention shown in  FIGS. 3A and 3B , the handle  10  is a bar-type handle which can be grasped with either an underhand or an overhand grip. With such a bar-type handle, the user&#39;s thumb will typically be positioned toward the first end  20  of the handle  10  when pulling the handle from the deployed state to an operative state. As explained previously, when the handle is in the operative state, this causes the door to be opened. Whilst not shown in the accompanying Figures, in the present embodiment, the operative state corresponds to a position in which the handle  10  is further rotated about the pivot means  24  beyond the deployed state. 
         [0076]    The operation of the retractable handle arrangement  1  will now be described in more detail. 
         [0077]    Referring to  FIGS. 4A ,  4 B and  4 C, with the handle  10  in the stowed state, the rocker arm  40  is disposed substantially vertical. The return spring  26  acts to bias the handle  10  towards the stowed state. Accordingly, the operating member  28  of the handle  10  presses against the second end  46  of the rocker arm  40  which, in turn, causes the first end  44  of the rocker arm  40  to press against the surface of the cam  38 , thereby ensuring frictional contact between the rocker arm  40  and the cam  38 . In order to deploy the handle  10 , the motor  30  is driven to rotate the worm gear  34  such that the gear wheel  36  and the cam  38  are rotated in the direction of arrow A in  FIG. 4A . 
         [0078]    Referring to  FIGS. 5A ,  5 B and  5 C, the cam  38  is profiled such that, as it rotates in the direction of arrow A, the radial distance r between the axis of rotation  42  and the surface of the cam  38  at the point of contact P between the cam  38  and the first end  44  of the rocker arm  40  increases. Thus, the rotation of the cam  38  causes the rocker arm  40  to be pivoted about the rocker axis  48 . The first end  44  of the rocker arm  40  moves in the direction of the arrow B in  FIG. 5A . This produces a corresponding movement of the second end  46  of the rocker arm  40  in the direction of arrow C in  FIG. 5C . The second end  46  of the rocker arm  40  presses against the operating member  28  of the handle  10  thereby causing the handle  10  to rotate about its pivot means  24  in the direction of arrow D in  FIG. 5C  until it reaches the deployed position at which point the motor  30  stops. 
         [0079]    As the cam  38  rotates from its initial position where the handle  10  is in the stowed state, the point of contact P between the surface of the cam  38  and the rocker arm  40  migrates towards the rocker axis  42 . Accordingly, the force applied to the operating member  28  of the handle  10  by the second end  46  of the rocker arm  40  varies. More specifically, during an initial deployment phase, the rocker arm  40  contacts the cam  38  proximate to its first end  44 , i.e. further away from the rocker axis  48 . The result is that a greater force is exerted on the operating member  28  during the initial phase, and thus a greater torque is applied to the handle  10 . The profile of the cam  38  is such that the rate of change of the radial distance r is relatively small during this initial phase. Accordingly, the handle  10  moves relatively slowly. 
         [0080]    As the cam  38  continues to rotate during a second deployment phase, the point of contact P moves closer to the rocker axis  48  and the force applied to the operating member  28  is reduced. This coincides with a more rapid increase in the radial distance r which results in the handle  10  being moved at a higher speed. 
         [0081]    Accordingly, with the above-described configuration a high force can be applied to the handle during the initial phase, such force being selected so as to be sufficient to break through any ice, in the event that the handle  10  is subjected to wet and freezing conditions (the required force may be about 200N). Once the handle  10  has been moved from the stowed state, the force applied to it is reduced and the speed of deployment is increased so that the user does not have to wait for a long time for the handle  10  to deploy. During deployment of the handle  10 , the motor  30  is driven at a constant speed of rotation. The configuration of the transmission means  32  modulates the force applied to the handle  10  and the speed at which the handle  10  is deployed. 
         [0082]    In order to retract the handle  10  from the deployed state back into the stowed state, the motor  30  is driven in reverse which, in turn, rotates the gear wheel  36  and the cam  38  in the direction opposite to arrow A in  FIGS. 4A and 5A . The biasing force of the return spring  26  causes the handle  10  to move toward the stowed state. As the handle  10  retracts, the operating member  28  causes the rocker arm  40  to rotate back to its initial position shown in  FIGS. 4A ,  4 B and  4 C. Accordingly, during retraction of the handle  10 , although the motor  30  is driven, the mechanism  18  does not exert a closing force on the handle  10 . This is advantageous because, in the event that a user is holding the handle  10  as it retracts, the force against the user&#39;s hand is limited to that of the return spring  26 . 
         [0083]    A further advantage of the above-described retractable handle arrangement  1  is that the transmission means  32  is protected from damage caused by abuse in the event that the handle  10  is pushed inwards when in the deployed state before it has been retracted by the mechanism  18 . More specifically, if the handle  10  is pushed inwards when in the deployed state, the operating member  28  presses against the surface of the cam  38 , but no force is transferred to the gear wheel  36  or the worm gear  34 . Accordingly, the mechanism is not back driven and the teeth of the gear wheel  36  are protected from damage. 
         [0084]    In a further embodiment of the present invention, the cam  38  profile may be such that there is a third deployment phase of the handle  10 . In more detail, the cam  38  may be profiled such that as it rate of change in the radial distance r reduces after the second deployment phase. Accordingly, after the handle  10  is moved quickly during the second phase, it slows down gradually during the third phase until it stops in the deployed state, thereby producing a pleasing aesthetic effect. 
         [0085]    It will be appreciated by those skilled in the art that, whilst the above description refers to initial, second and third deployment phases, the cam  38  has a continuous surface and, therefore, the transitions between each of the deployment phases are continuous. 
         [0086]    Furthermore, it is an advantage of the handle arrangement  1  of the present invention that the deployment speed/force profile can be easily tuned for a variety of applications by simply installing a cam  38  with the desired surface profile. 
         [0087]    Referring to  FIG. 6 , the handle  10  may also comprise an unlock button  50  and a lock button  52  disposed on the outer surface  16  thereof. The buttons  50 ,  52  may be touch sensitive buttons, i.e. capacitive sensors, or they may be microswitches. The full functionality of the buttons  50 ,  52  will be described in more detail later. However, the positions of the buttons  50 ,  52  on the handle  10  are selected so as to be both intuitive for the user and to reduce the possibility of incorrect use of the handle arrangement  1 . 
         [0088]    The unlock button  50  is disposed adjacent to the first end  20  of the handle  10 . As mentioned previously when a user operates the handle  10  the user&#39;s thumb will typically be at the first end  20 . Thus, when a user presses the unlock button  50  with their thumb, which unlocks the associated door and causes the handle  10  to be moved into the deployed state, their hand is naturally positioned such that it is easy and convenient for them to grasp the deployed handle  10  and open the door by pulling it to the operative position. 
         [0089]    Furthermore, the unlock button  50  is advantageously positioned in the event that a user is required to deploy the handle  10  manually, for example, if there is a loss of power to the motor  30 . In this case, as the user applies pressure to the unlock button  50 , the associated door will be unlocked as before. Subsequently, as the user applies increased pressure on the unlock button  50 , the handle  10  will be rotated about the pivot means  24  against the biasing force of the return spring  26 . Once the second end  22  of the handle protrudes from the slot  14 , the user can grasp the handle  10  and pull it to the operative state to open the door. Accordingly, the handle  10  can be manually deployed by a user simply applying pressure at the unlock button  50 , without requiring any more complex actions which require a greater degree of dexterity. 
         [0090]    The lock button  52  is disposed adjacent to the pivot means  24  of the handle  10 . As will be explained in more detail later, the handle  10  will usually be in the deployed state when its associated door is unlocked and pressing the lock button  52  will cause the door to be locked and the handle  10  to be retracted to the stowed state. As mentioned previously, it is undesirable for a user to press the handle  10  toward the stowed state when it is deployed because, whilst not causing damage to gear wheel  36 , it puts pressure on the rocker arm  40 , which could cause it to bend. Accordingly, the position of the lock button  52  adjacent to the pivot means  24  of the handle  10  is advantageous because any pressure applied to the lock button  52  will not cause rotation of the handle  10  about the pivot means  24 . 
         [0091]    Furthermore, with the above described arrangement, the functions of the unlock and lock buttons  50 ,  52  will be intuitive to a user unfamiliar with the operation of the handle arrangement  1 . In particular, the position of the unlock button  50  at the first end  20  of the handle  10  will be associated in the mind of the user with opening the door because pressure at this position on the handle  10  causes it to move from the stowed to the deployed state. It follows that the other button  52  will be associated with locking because a user will naturally associate the presence of two buttons on the handle  10  with locking and unlocking functions. 
         [0092]    The above-described arrangement achieves this effect whilst ensuring that the lock button  52  is located in a position which is convenient for a user to press and which will not cause damage to the mechanism  18  of the handle arrangement  1  if pressed with a high force. 
         [0093]    Referring to  FIG. 7 , a system for controlling a retractable handle arrangement  1  of the kind described above comprises a control module  54  for controlling the mechanism  18  of each retractable handle arrangement  1  on a vehicle. Although only a single handle arrangement is shown in  FIG. 7 , it will be appreciated that each door of the vehicle may be provided with one. 
         [0094]    The control module  54  is also coupled to a wireless communication module  56 , a vehicle speed sensor  58 , a vehicle alarm system  60 , door lock and unlock controls in the vehicle cabin  62 , a handle light  64  and a door ajar switch  66 . The wireless communication module  56  is operable to receive signals from a vehicle key fob  68 . The key fob  26  is provided with respective door lock and unlock buttons and means for transmitting respective lock and unlock signals to the wireless communication module  56  in response to a user pressing the relevant button. The wireless communication module  56  is also operable to detect the presence of a smart key  70  within a target distance from the vehicle (typically 1-2 m) to enable passive entry. Also, the driver&#39;s door of the vehicle can be mechanically locked or unlocked from outside the vehicle via a key barrel positioned underneath the driver&#39;s door handle. Thus, the key barrel will be revealed any time the handle is moved to the operative state. 
         [0095]    Each retractable handle arrangement  1  may comprise a light  64 , such as an LED, for illuminating the handle  10  and its immediate surroundings so as to facilitate the opening of the doors in low-light conditions. Each retractable handle arrangement  1  may also comprise a pair of limit switches for detecting when the handle  10  is in each of the stowed and deployed states. 
         [0096]    The operation of the control module  54  will now be described in more detail. 
         [0097]    When the vehicle is parked, each handle  10  is in the stowed state, i.e. flush with the door skin  12 , when its associated door is locked, and each handle  10  is in the deployed state when its associated door is unlocked. Deployment is thus triggered by unlocking and retraction by locking. 
         [0098]    Locking and unlocking are triggered by either using the lock and unlock buttons on the key fob  68  or the passive entry lock and unlock buttons  50 ,  52  provided on each handle  10 . More specifically, for access via passive entry, the user carries the smart key  70  on their person. When the smart key  70  is within a target range of a particular door handle  10  (typically 1-2 m) and the door unlock button  50  is operated, the control module  54  is operable to verify the presence of the smart key  70 , by virtue of a signal received via the wireless communication module  56 , and the handles  10  of all unlocked doors are deployed. The user can then open an unlocked door by pulling the associated handle  10  to its operative position thereby mechanically releasing the door latch. Each handle  10  returns to the stowed state when its associated door is locked. This may be achieved by a user pressing the lock button  52  on the handle  10  or by means of a cabin lock button  62  within the vehicle or the lock button on the key fob  68 . 
         [0099]    Accordingly, the deployment position of each handle  10  acts as a lock status indicator for each individual door. One exception to this may be provided when the vehicle is in motion in which case all the handles  10  of all doors, whether locked or unlocked, are in the stowed state. The handles  10  on any unlocked doors may be retracted into the stowed state in the event that the vehicle exceeds a threshold speed, for example, 5 miles per hour, which may be determined by the vehicle speed sensor  58 . The handles  10  of the unlocked doors will then remain in the stowed state for the duration of the vehicle&#39;s journey and are only re-deployed in the case that the vehicle is determined to be stationary and either (i) one of the doors is opened from the inside (which can be determined by means of the door ajar switch  66  provided on each door), (ii) in the case that an unlocked door&#39;s handle unlock button  50  is operated by a person, even without the smart key  70  present (such as when picking up a passenger), or (iii) if the cabin unlock button  62  is pressed. 
         [0100]    Pressing the handle lock button  52  once will centrally lock the vehicle and, if applicable, arm the vehicle alarm system  60 . If the lock button  52  is pressed a second time within a predetermined time period, e.g. 3 seconds, a deadlock will be activated. The handles  10  will be retracted to the stowed state in response to the first press of the lock button  52 . A ‘global close’ may be affected by pressing and holding the lock button  52 , i.e. this may automatically close any open windows, and, if applicable to the vehicle, deploy a retractable roof, etc. 
         [0101]    The handle light  64  will be switched on when the vehicle is unlocked and turned off when the vehicle is locked. If the vehicle is left in an unlocked state for more than a predetermined period of time, e.g.  20  seconds, the light  64  will turn off. Also, the light  64  will not be activated when the ignition is on. 
         [0102]    A user need not wait for a handle  10  to fully deploy after pressing the handle unlock button  50  before opening the door, provided the user is able to grasp the handle  10  as it is being deployed sufficient to pull it to the operative state. 
         [0103]    Referring to  FIGS. 8A ,  8 B and  8 C, an alternative embodiment of a handle  100  for use in the above-described retractable handle arrangement  1  comprises a top cover portion  72  which extends substantially perpendicular to the inner surface  17  along the length of the handle  100  and along a portion of the second end  22 . The handle comprises an elongate element. 
         [0104]    The presence of the top cover portion  72  requires a user to grasp the handle  100  with an underhand grip in order to open the associated door. An advantage of this handle configuration over the bar-type handle described previously is that the top cover portion  72  prevents items, such as clothing, bag straps, etc. from becoming looped over the handle  100  when it is in the deployed state. Accordingly, such a handle offers an improved safety aspect. 
         [0105]    In the this embodiment the top cover portion extends down the end of the handle, but the skilled person would appreciate that there may be provided a top cover portion and a separate end cover portion, as long as the arrangement performed the function of preventing items becoming looped over the handle. 
         [0106]    It will be appreciated that the shape of the cam, or profile of the cam, may be varied to provide a desired characteristic, for example: the force or torque with which the handle is moved or pivoted during the deployment phase and/or stowing phase of the handle movement may be controlled or modulated by the cam profile; the speed, degree of displacement or rotation and acceleration with which the handle moves during the deployment phase and/or stowing phase of the handle movement may be controlled or modulated by the cam profile. The force or torque is modulated by determining and/or controlling the distance between the point at which the cam contacts the rocker arm and the pivot or fulcrum of the rocker arm. The degree of displacement, the angle through which the handle rotates can be controlled by selecting the maximum radial distance r which the cam displaces the rocker arm. The speed and/or acceleration of the handle are controlled by the rate of change in the radial distance r. It will be understood that the cam profile may be chosen to maintain a constant speed or a constant force throughout the deployment or stowing phase. It will also be appreciated that the cam profile may be asymmetric such that the characteristics are different in the deployment phase and the stowing phase, in such embodiments the motor may be driven in a constant rotational direction so as to employ a first portion of the cam profile for controlling the deployment phase and a second portion for controlling the stowing phase. 
         [0107]    It will also be appreciated that the shape or profile of the rocker arm may also be varied.