TECHNICAL FIELD

The present disclosure relates to an actuator mechanism, a sliding door arrangement, a control system and a vehicle. In particular, but not exclusively it relates to a sliding door arrangement for a road vehicle and a road vehicle.

BACKGROUND

Doorways on vehicles, such as buses, are known that are provided with two doors that have abutting edges that are provided with a seal to prevent ingress of water, wind, etc. The doors may be arranged to have a plug and slide motion and arranged to open and close simultaneously, so that the seal is only subjected to compression during closing and it is not subjected to shearing forces as it would be if the doors were opened or closed individually.

In an alternative design a sliding access door can be arranged so that in its closed position it abuts against a fixed structure on the vehicle, providing the resistance to the door seal during compression, and often providing additional structural reinforcement to the vehicle body, commonly referred to as a‘B-pillar’. This fixed B-pillar provides a vertical constraint to the open & accessible area of the vehicle when the door is fully open.

In an alternative design a vertical structural member can be incorporated into one or more of the opening doors. A pair of sliding doors may be arranged to overlap so that a specified one of the two doors may be opened without opening the other door. However, the specified one of the two doors must be opened before the other door can be opened, and then the specified door must be closed after the other door is closed.

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 sliding door arrangement for a vehicle and a vehicle as claimed in the appended claims. According to an aspect of the present invention, there is provided an actuator mechanism for a sliding door of a vehicle having a vehicle body, the actuator mechanism comprising a motor, a gear train, a push member and a screw mechanism, the push member and the screw mechanism being rotatably coupled to the motor via the gear train wherein the actuator mechanism is configured such that, in use, operation of the motor causes the push member to act against the vehicle body so as to displace the door in a first direction towards a partially open position of the door in which at least a first side edge of the door is disposed outwardly of a door aperture and further operation of the motor causes the screw mechanism to displace the door in a second direction substantially perpendicular to the first direction towards a fully open position of the door.

According to a further aspect of the present invention, there is provided an actuator mechanism for a sliding door movable between closed and open positions relative to a door frame, the actuator mechanism comprising an epicyclic gear system comprising a sun gear, a ring gear having toothed inner and outer surfaces, and a plurality of planet gears rotatably mounted to a carrier, the planet gears being in geared engagement with the sun gear and the toothed inner surface of the ring gear a displacement gear system comprising a connecting gear fixedly mounted to the carrier for rotation therewith, a pusher gear in geared engagement with the connecting gear, and a push member mounted eccentrically to the pusher gear a screw mechanism comprising a nut having an internal thread and a toothed outer surface, a shaft fixedly mountable to the door and in threaded engagement with the internal thread of the nut, and a toothed belt in toothed engagement with the outer surface of the nut and the outer surface of the ring gear and a motor drivingly connected to the sun gear wherein the mechanism is arranged such that in the closed position of the door, rotation of the sun gear by the motor causes the push member, via rotation of the sun gear, the connecting gear and the pusher gear, to displace the screw mechanism and at least a portion of the door in a first direction relative to the door frame towards a partially open position of the door; and in the partially open position of the door, rotation of the sun gear by the motor causes the shaft, via rotation of the sun gear, the planetary gears, the ring gear and the nut, to be displaced linearly relative to the nut thereby to displace the door in a second direction substantially perpendicular to the first direction towards a fully open position of the door.

Optionally, the screw mechanism comprises a spindle defining a helical groove and wherein the drive gear comprises a bore configured to engage the helical groove to drive the screw mechanism through the bore. Optionally, the bore is configured to compliment the outer surface of the screw mechanism and is provided with a helical thread configured to locate in the helical groove of the screw mechanism.

Optionally, the nut comprises a ball-screw provided with an external toothed surface configured to engage with the toothed belt.

Optionally, the screw mechanism is fixed to the door by a bracket at each end of the screw mechanism, such that the screw mechanism is fixed parallel to the door and unable to rotate on its axis.

Optionally, the sliding door arrangement comprises a plurality of sliding doors, wherein each of the doors comprises an actuator mechanism.

According to a further aspect of the present invention, there is provided a control system comprising a motor, a gear train, a push member and a screw mechanism, the control system configured to receive a signal indicative of a door movement request control the motor to actuate such that the push member is configured to act against a body of the vehicle so as to displace a door of the vehicle in a first direction toward a partially open position of the door, in which at least a first side edge of the door is disposed outwardly of a door aperture of the body of the vehicle and further control the motor so as to cause the screw mechanism to displace the door in a second direction, substantially perpendicular to the first direction, toward a fully open position of the door.

Optionally, there is provided a vehicle comprising the sliding door and the actuator mechanism, the sliding door arrangement and/or the control system.

According to a further aspect of the invention there is provided a sliding door arrangement for a vehicle, comprising: a first door comprising a first door panel having a first side edge and a second side edge opposite to the first side edge; first actuation means configured to move the first side edge of the first door from a doorway while the second side edge of the first door remains within the doorway and configured to cause the first door to slide to an open position with the first side edge leading; and guide means for guiding the second side edge of the first door out from the doorway while the first door is caused to slide to the open position. This provides the advantage that the first door is caused to move in such a way that it may be provided with a seal on its second side edge that buts up against another door, and the first door may be moved into and out of the doorway while the other door remains closed, without subjecting the seal to shear forces that could damage it. Instead, the seal is only subjected to compression as the first door is closed. Similarly, if the first door is a single door that extends across the entire doorway when it is closed, a seal may be provided on its second side edge to seal against the side of the doorway, or the seal may be provided on the doorway to seal against the second side edge. In each case, due to the way in which the door is caused to close and open, it does not exert shear forces on the seal but only subjects it to compression.

Optionally, the first actuation means comprises a first linear actuator configured to cause the first door to slide to the open position.

Optionally, the first door comprises a first rail extending laterally across the first door panel; and the first actuation means includes a first rail drive gear configured to drive the first rail along its length to cause the first door to slide. This provides the advantage that the position of the door is able to be controlled during opening and closing without the need for an external rail on the outside of the body of the vehicle. Therefore the design of the outside of the body does not have to be limited by the need for the external rail. For example, the body may curve away from the door in its open position, or, in its open position, the door may extend further away from the doorway than the body of the vehicle does. I.e. the opening travel of the door is not limited by linearity of the side of the vehicle or vehicle length.

Optionally, the first rail comprises a first spindle defining a helical groove and the first rail drive gear has a bore configured to engage the helical groove to drive the first spindle through the bore. This provides the advantage of a compact and robust mechanism for causing the sliding of the door.

Optionally, the first actuation means comprises an electric motor arranged to move the first rail at an angle to the doorway and thereby cause the first side edge of the first door to move from the doorway. This provides the advantage that the door is moved to a position where it can be withdrawn from a second door, or a side of the doorway (in the case of a single door arrangement), without moving the second side edge out from the doorway. Optionally, the first actuation means comprises a motor arranged to move with the first door as the first side edge of the first door is moved from the doorway and to cause the first door to move with respect to the motor as the first door slides to the open position. This provides the advantage that a single motor may be used for the entire movement of the door.

Optionally, the first actuation means comprises a single motor and a gear mechanism driven by the single motor, the gear mechanism being configured to move the first side edge of the first door from the doorway and configured to cause the first door to slide to the open position. This provides the advantage that the sequencing of the two movements may be programmed by the design of the gear mechanism. Thus, for example, sensors are not required to indicate when the first side edge has been removed from the doorway to determine when the sliding to the fully open position can begin.

Optionally, the gear mechanism comprises an epicyclic gear train configured to operate in a first mode to move the first side edge of the first door from the doorway and to operate in a second mode to cause the first door to slide to an open position. This provides the advantage that a relatively simple gearing arrangement is able to perform both movements of the door.

Optionally, the first actuation means comprises a first motor and a first gear mechanism configured to move the first side edge of the first door from the doorway and a second motor and second gear mechanism configured to cause the first door to slide to the open position. This provides the advantage that the gear mechanism may be simplified, when compared to an arrangement with a single motor.

According to another aspect of the invention there is provided a vehicle comprising the sliding door arrangement according to any one of the previous paragraphs, wherein: the vehicle comprises a body defining a cabin and the doorway is provided in the body to allow access into the cabin; and the first door is moveable between a closed position where it extends across at least a first part of the doorway and an open position to provide access through the first part of the doorway.

Optionally, the guide means comprises a first track attached to the body of the vehicle and a first carriage attached to the first door, the first carriage being configured to follow a path defined by the track. Optionally, the first carriage comprises a roller configured to locate within a groove formed in the first track.

Optionally, the first track is positioned along the bottom of the first door and the guide means comprises a second track positioned along the top of the first door to guide a second carriage that is attached to the first door. This provides the advantage that the position of the door may be kept stable during its opening and closing.

Optionally, the first rail is positioned part way up the first door at a height above the level of a floor of the cabin.

Optionally, the sliding door arrangement comprises a second door comprising a second door panel having a first side edge and a second side edge opposite to the first side edge of the second door, wherein the second side edge of the second door butts up against the second side edge of the first door when the first doors are in a closed position. This provides the advantage that the doors in combination are able to span across a wide doorway and enable easy ingress and egress when both doors are opened, but allow access through just a selected one of the doors when such a wide opening is not required.

Optionally, the sliding door arrangement comprises: second actuation means configured to move the first side edge of the second door from the doorway while the second side edge of the door remains within the doorway and configured to cause the second door to slide to an open position with its first side edge leading; and second guide means for guiding the second side edge of the second door out from the doorway while the second door is caused to slide to an open position. This provides the advantage that a seal may be provided between the first door and the second door and the second door may be moved into and out of the doorway while the first door remains closed, without subjecting the seal to shear forces that could damage it. Instead, the seal is only subjected to compression as the first door is closed.

Optionally, the second actuation means comprises a second linear actuator configured to cause the second door to slide to its open position.

Optionally, the sliding door arrangement comprises a control system configured to: cause the actuation means to open the first door while the second door remains closed, in dependence on receiving a signal indicating that only the first door is to be opened; and cause the actuation means to open the first door and the second door at the same time, in dependence on receiving a signal indicating that both the first door and the second door are to be opened.

Optionally, the control system is configured to cause the actuation means to open the second door while the first door remains closed, in dependence on receiving a signal indicating that only the second door is to be opened.

A first direction describes movement substantially perpendicular to the intended direction of motion of the vehicle. The second direction describes movement substantially perpendicular to the first direction, in a direction substantially parallel to the intended direction of motion of the vehicle.

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:

Fig. 1 shows a road vehicle embodying the present invention with its doors closed;

Fig. 2 shows the road vehicle of Fig. 1 with its doors open;

Figs. 3 to 7 show a top view the doorway in a side wall of the body of the vehicle with a rear door in a closed position and a front door in a closed position in Fig. 3, intermediate positions in Figs. 4, 5 and 6 and a fully open position in Fig. 7;

Fig. 8 shows internal components of a first actuation means for a door of the vehicle;

Fig. 9 shows internal components of the first actuation means but with some components omitted to enable other components to be shown more clearly; Fig. 10 shows a portion of a spindle and a cross-section of a drive gear, which form a part of the actuation means;

Fig. 1 1 shows a top view of the doors of the vehicle in closed positions, lower tracks that provide a guide means for a rear edge of the doors, the internal components of the actuation means and a lower portion of housing carriers, which support and guide the actuation means; Fig. 12 shows the same view as Fig. 1 1 but with the doors in an intermediate position between closed and fully open;

Fig. 13 shows the same view as Fig. 1 1 but with the doors in a fully open position;

Figs. 14 and 15 show a side view of a connecting gear, a pusher gear and a push member of the actuation means and a portion of the housing carrier to which the push member is connected;

Fig. 16 shows a top view of an alternative first actuation means along with the side wall of the body of the vehicle and the first door in its closed position;

Fig. 17 shows the same view as Fig. 16 but with the first door in an intermediate position;

Fig. 18 shows the same view as Fig. 16 but with the first door in a fully open position;

Fig. 19 shows a schematic diagram of the control system shown in Figs. 1 and 2; and

Fig. 20 shows a flowchart illustrating a method of controlling operation of two doors of a vehicle;

DETAILED DESCRIPTION

A vehicle 100 comprising a sliding door arrangement 130 in accordance with an embodiment of the present invention is described herein with reference to the accompanying Figs. 1 to 15, 19 and 20.

With reference to Figs. 1 and 2, the vehicle 100 is a road vehicle having a body 101 supported on road wheels 102. The body 101 defines a cabin 103 and a doorway 105 in the side of the vehicle 100 to enable entry and exit into the cabin 103. In the present embodiment the cabin 103 contains seats 104 (shown in Fig. 2) to enable users of the vehicle 100 to be seated, but it will be appreciated that in other embodiments the vehicle 100 may be configured to carry goods rather than passengers.

The vehicle 100 has a door arrangement 130 comprising a front door 106 and a rear door 107. In their closed positions as shown in Fig. 1 , the front door 106 has a rear edge 1 13 abutting a front edge 1 19 of the rear door 107. The front door 106 has a front edge 303 at a front side of the doorway 105 and the rear door 107 has a rear edge 31 1 at a rear side of the doorway 105, so that in combination the doors 106 and 107 extend across the full width of the doorway 105 when they are in their closed positions.

The doors 106 and 107 are moveable between the closed positions of Fig. 1 and the open positions of Fig. 2 by a plug and slide process that allows the doors 106 and 107 to be opened and closed simultaneously or opened and closed individually, as will be described in detail below.

Upper tracks 108A and 108B extend along the body 101 of the vehicle 100 above the doorway 105 and similarly shaped lower tracks 109A and 109B extends along the body 101 below the doorway 105. The front door 106 comprises an outer panel 1 10, and the outer panel 1 10 has an upper carriage 1 1 1 attached to it, adjacent to its upper edge 1 12 and its rear edge 1 13. The upper carriage 1 1 1 is located within the upper track 108A and is configured to move along a path defined by the upper track 108 during opening and closing of the front door 106. The front door 106 also has a lower carriage 1 14 attached to its outer panel 1 10, adjacent to its lower edge 1 15 and its rear edge 1 13. The lower carriage 1 14 is located within the lower track 109A and is configured to move along a path defined by the lower track 109A during opening and closing of the front door 106. The carriages 1 1 1 and 1 14 therefore provide a guide means for guiding the rear edge 1 13 of the front door 106 out from the doorway 105 while the front door 106 is caused to slide to the open position.

In the present embodiment, the tracks 108A and 109A comprise U-shaped channels and the carriages 1 1 1 and 1 15 each comprise a roller to facilitate their movement along the tracks 108A and 109A.

The rear door 107 comprises an outer panel 1 16, and the outer panel 1 16 has an upper carriage 1 17 attached to it, adjacent to its upper edge 1 18 and its front edge 1 19. The upper carriage 1 17 of the rear door 107 is located within the upper track 108B and is configured to move along a path defined by the upper track 108B during opening and closing of the rear door 107. The rear door 107 also has a lower carriage 120 attached to its outer panel 1 17, adjacent to its lower edge 121 and its rear edge 1 19. The lower carriage 120 of the rear door 107 is also located within the lower track 109B and is configured to move along a path defined by the lower track 109B during opening and closing of the rear door 107. The carriages 1 17 and 120 of the rear door 107 and the tracks 108B and 109B may be similar to those of the front door 106.

The front door 106 has a first rail 122 fixed to its outer panel 1 10. The first rail 122 extends laterally across the inner side of the outer panel 1 10. In the present embodiment the first rail 122 is positioned part way up the first door 106 at a height above the level 201 of a floor 202 of the cabin 103. The door arrangement 130 also comprises a first actuation means 123 configured to cause opening and closing of the front door 106. In the present embodiment, the first actuation means 123 is controlled by a control system 124, which provides signals to cause operation of the actuation means 123 in dependence on signals received by the control system 124. For example, the front door 106 comprises a user input device 131 configured to receive user inputs indicative of requests to open and to close the front door 106.

The rear door 107 has a second rail 125 fixed to its outer panel 1 17. The second rail 125 extends laterally across the inner side of the outer panel 1 17 and at the same height as the first rail 122. The door arrangement 130 also comprises a second actuation means 126 configured to cause opening and closing of the rear door 107. The second actuation means 126 is also controlled by the control system 124. For example, the rear door 107 comprises a second user input device 131 configured to receive user inputs indicative of requests to open and to close the rear door 107. The vehicle 100 comprises at least one other user input device (not shown) that is inside the vehicle 100 to enable occupants of the cabin 103 to provide similar requests to the control system 124 to open and to close the front door 106 and/or the rear door 107.

Figs. 3 to 7 illustrate the manner in which the front door 106 is opened and closed by the 123 actuation means 123. The rear door 107 may be similarly configured to the front door 106 and it is opened and closed by the second actuation means 126 in a similar manner to the front door 106.

Each of Figs. 3 to 7 show a top view of the front door 106, the rear door 107, and a side wall 301 of the body 101 of vehicle 100, which defines the doorway 105. The front door 106 is shown closed and positioned within the doorway 105 in Fig. 3, in various stages of opening (or closing) in Figs. 4 to 6, and fully open in Fig. 7. The rear door 107 is shown closed in Figs. 3 to 7. The first actuation means 123 comprises an actuator housing 302 that is arranged to be moveable with the first door 106 as a front edge 303 of the front door 106 is pushed out of the doorway 105 and pulled into the doorway by the first actuation means 123. In the present embodiment, the vehicle 100 also comprises a housing carrier 304 that is fixed to the body 101 of the vehicle 100 within the cabin 103, and the actuator housing 302 and housing carrier 304 are provided with interacting features that enable the housing carrier 304 to support the actuator housing 302 and guide its motion during movement of the front edge 303 of the door 106 into and out of the doorway 105. In the present embodiment, the housing carrier 304 is provided with a slot 305 and the actuator housing 302 has a post 306 fixed to it that extends into the slot 305, so that it is able to move along the slot 305. However, other arrangements for controlling this movement may be provided in alternative embodiments.

As the front edge 303 of the front door 106 is pushed out from the doorway 105, the movement of the rear edge 1 13 of the front door 106 is constrained by the movement of the upper carriage 1 1 1 in the upper track 108A and the lower carriage 1 14 in the lower track 109A. (Only the lower carriage 1 14 and the lower track 109A are shown in Figs. 3 to 7, but it should be understood that the upper carriage 1 1 1 and the upper track 108A are similarly configured.) The front door 106 is shown after this initial movement in Fig. 4. In the present embodiment, the tracks 108A and 109A have two end portions 307 and 308 that extend parallel to the doorway 105 and an obliquely angled portion 309 that joins them. Thus, during initial opening of the front door 106, the carriages 1 1 1 and 1 14 move along the first end portion 307, which holds the rear edge 1 13 of the door 106 within the doorway 105 and only allows movement of the rear edge 1 13 of the front door 106 along the vehicle 100 away from the rear door 107.

In the present embodiment, movement out from the doorway 105 of the front edge 303 of the front door 106 is limited, by the post 306 reaching the end of the slot 305 in the housing carrier 304 as shown in Fig. 4. The first actuation means 123 then causes the rail 122 to move linearly with respect to the actuator housing 302, with its front edge 303 leading, so that the front door 106 is slid sideways away from the doorway 105.

During this movement the carriages 1 1 1 and 1 14 firstly travel along the first end portion 307 of the tracks 108A and 109A and thereby keep the rear edge 1 13 of the front door 106 within the doorway 105 until the carriages 1 1 1 and 1 14 reach the oblique portion 309 of the tracks 108 and 1 15 as shown in Fig. 5. The carriages 1 1 1 and 1 14 then travel along the oblique portions 309 of the tracks 108A and 109A, which causes the rear edge 1 13 of the front door 106 to move out from the doorway 105, so that the outer panel 1 10 becomes positioned substantially parallel to the doorway 105 and the side wall of the body 101 , as shown in Fig. 6. During further movement of the door 106, the carriages 1 1 1 and 1 14 travel along the second end portion 308 of the tracks 108A and 109A until the front door 106 reaches its fully open position as shown in Fig. 7. It should be noted that the geometry of these rail portions 307, 308 and 309 defines the movement path of the opening door and may be altered to suit each required vehicle.

During closing of the front door 106, the process is reversed. Thus, initially the actuation means 123 firstly causes the rail 122 to move linearly with respect to the actuator housing 302, while the carriages 1 1 1 and 1 14 travel along the tracks 108A and 109A through the positions shown in Figs. 6 and 5 to the position of Fig. 4. The first actuation means 302 then pulls the front edge 303 of the front door 106, back into the doorway 105, while the movement is guided by the movement of the post 306 on the actuator housing 302 along the slot 305 in the housing carrier 304.

A seal 310 is provided on the rear edge 1 13 of the front door 106, so that it is positioned between the rear edge 1 13 of the front door 106 and the front edge 1 19 of the rear door 107 when the doors 106 and 107 are both closed, as shown in Fig. 3. Advantageously, the initial movement of the front door 106 away from the rear door 107 during opening, and its final movement towards the rear door 107 during closing are both along the length of the vehicle 100 and therefore the seal 310 is compressed during closing of the doors 106 and 107 and it is not subjected to any shearing movement. The seal 310 is compressed between doors 107 and 106 only, not requiring any intermediate vertical structure on the vehicle (commonly referred to as a B-pillar) to provide the reaction force for adequate sealing performance.

It should be understood that the rear door 107 may be opened and closed by the actuation means 126 in a similar manner to way that the front door 106 is opened and closed by the first actuation means 123. Consequently, the rear door 107 may be opened and closed while the front door remains closed, or alternatively the front door 106 and the rear door 107 may be opened and closed simultaneously.

The internal components of the actuation means 123 are shown in Fig. 8 without the actuator housing 302. Fig. 9 shows the same arrangement as Fig. 8 but with some components of the actuation means 123 omitted to enable other components of the actuation means 123 to be seen. In the present embodiment the actuation means 123 comprises a single electric motor 801 and a gear mechanism 802 driven by the single motor 801 . The gear mechanism 802 is configured to move the front side edge 303 of the front door 106 from the doorway 105 as shown in Fig. 4 and configured to cause the front door 106 to slide to the open position as illustrated in Figs. 5 to 7.

The gear mechanism 801 comprises an epicyclic gear train (or planetary gear) 803 as may best be seen in Fig. 9. The sun gear 804 (shown in Fig. 9) of the epicyclic gear train 803 is driven directly by the electric motor 801 , and the sun gear 804 is arranged to drive planet gears 805 that are mounted to rotate about their axes on a carrier 806. The carrier 806 is fixed to a connecting gear 807 that is configured to drive a pusher gear 808 (shown in Fig. 8). A push member 809 is pivotally attached to the pusher gear 808 at a pivot position 810 close to the peripheral surface of the pusher gear 808, so that as the pusher gear 808 is caused to rotate, the pivot position 810 moves closer to or further from the door 106 (not shown in Figs. 8 and 9).

The planet gears 805 of the epicyclic gear train 803 are surrounded by a ring gear 81 1 that is provided with a toothed outer surface so that it is able to drive a toothed belt 812, and thereby drive a drive gear 813. Rotation of the drive gear 813 is arranged to cause linear movement of the rail 122. In the present embodiment, the rail 122 comprises a crew mechanism that may comprise, a spindle defining a helical groove 814 and the drive gear 813 has a bore (1001 shown in Fig. 10) configured to engage the helical groove 814 to drive the spindle 122 through the bore 1001 . Fig. 10 shows a portion of the spindle 122 and a cross-section of the drive gear 813. The bore 1001 is configured to compliment the outer surface of the spindle 122 and is provided with a helical thread 1002 configured to locate in the groove 814 of the spindle. In an alternative embodiment, the drive gear 813 may comprise a ball-screw provided with an external toothed surface 815 so that it may be driven by the toothed belt 812.

The spindle 122 is fixed to the door 106 by a bracket 816 at each of its ends, so that the spindle 122 is fixed parallel to the door 106 and unable to rotate on its axis.

In alternative embodiments, the screw mechanism may comprise an alternative type of linear actuator, such as a rack and pinion. The operation of the first actuation means 123 is illustrated in Figs. 1 1 , 12 and 13, which provide a top view of the doors 106 and 107, the lower tracks 109A and 109B, the internal components of the actuation means 123 and 126 and a lower portion 1 101 of the housing carriers 304.

The operation is also partially illustrated by Figs. 14 and 15 which show a side view of the connecting gear 807, the pusher gear 808, the push member 809 and a portion 1 101 of the housing carrier 304 to which the push member 809 is connected.

Although the description of Figs. 1 1 to 15 refers to the front door 106 and its actuation means 123, it should be understood that the rear door 107 and its actuation means 126 may operate in a similar manner, as illustrated in those Figures.

The front door 106 is shown in its closed position in Fig. 1 1 , and Fig. 14 shows the position of the pusher gear 808 when the door 106 is closed. In this position, the pivot position 810 is at its closest position to the front door 106 and therefore its most distant position from the housing carrier 304. The push member 809 has a first end attached to the pusher gear 808 at the pivot position 810 and a second end that is attached to the housing carrier 304, so that it is able to pivot with respect to the housing carrier 304 along an axis 1 102 (shown in Fig. 1 1 ) but also travel along the axis 1 102. For example the end of the push member 809 may be hingedly attached to a cylindrical slug 1 103 retained within cylindrical bores 1401 (shown in Figs. 14 and 15) provided on the housing carrier 304 so that it is able to slide along the axis 1 102.

When the motor 801 is operated to open the front door 106, initially the front door 106 is unable to move along the length of the vehicle 100 due to it being located within the doorway 105. Consequently the drive gear 813 is unable to rotate and so the ring gear 81 1 (shown in Figs. 8 and 9) of the epicyclic gear train 803 is also unable to rotate. This causes the motor 801 to drive the pusher gear 808 via the sun gear 804, the planet gears 805, the carrier 804 and the connecting gear 807. The pusher gear 808 pushes the pusher member 809 in the direction of the housing carrier 304 but because the housing carrier 304 is fixed to the body 101 of the vehicle 100, this results in the pusher member 809 pushing the actuation means 123 and thereby pushing the front edge 303 of the front door 106 out from the doorway 105 to the position shown in Fig. 12. When the front edge 303 of the door 106 is out of the doorway 105 so that the spindle 122 is able to move with respect to the drive gear 813, the gear ratios of the epicyclic gear train 803 cause the ring gear 81 1 to rotate in preference to the carrier 806, and so the drive gear 813 is caused to rotate and drive the spindle 122 linearly through its bore 1001 (shown n Fig. 10). As the spindle 122 is fixed to the front door 106 by brackets 816 (shown in Fig. 8), the front door 106 is also moved linearly with respect to the drive gear 813. Consequently the front door 106 slides to the fully open position shown in Fig. 13. The vehicle 100 may be provided with sensors (not shown) configured to detect when the door 106 has reached its fully open position and provide signals indicative of this. On receipt of such a signal, the control system 124 is arranged to control the actuation means 123 to prevent any further rotation of the motor 801 .

Closing of the front door 106 is caused by a reverse motion of the motor 801 which initially drives the drive gear 813 via the ring gear 81 1 of the epicyclic gear train 803 and the toothed belt 812. The rotation of the drive gear 813 causes linear motion of the spindle 122 through the drive gear 813 and thereby slides the door 106 back to the position shown in Fig. 12. At that position, the door 106 is prevented from further similar movement, for example, by the carriages 1 1 1 and 1 14 reaching the end of the tracks 108A and 109A and/or another part of the front door 106 hitting another stopping means. The prevention of further movement of the front door 106 relative to the drive gear 813 prevents the drive gear 813 and the ring gear 81 1 from rotating, and so the rotation of the sun gear 804 causes rotation of the carrier 806 and this in turn causes the pusher gear 808 to rotate back to the position of Fig. 1 1 . The rotation of the pusher gear 808 moves the pivot position 810 of the push member 809 back to its position of Fig. 1 1 and the action of the slug 1 104 pulling on the bores 1401 of the housing carrier 304 causes the door 106 to be pulled back into the doorway 105 as shown in Figs. 1 1 and 14. The vehicle 100 may be provided with sensors (not shown) configured to detect when the door 106 has reached its fully closed position and provide signals indicative of when the door 106 has reached its fully closed position. On receipt of such a signal, the control system 124 is arranged to control the actuation means 123 to prevent any further rotation of the motor 801 .

The front door 801 may also be provided with electromechanical latches (not shown) that are operated to latch the front door 106 against the body 101 when the door 106 has reached its fully closed position and operated to unlatch before the actuation means 123 is activated to cause opening of the front door 106. An alternative first actuation means 123 is shown in the top view of Figs. 16, 17 and 18 along with the first door 106 and the side wall 301 of the body 100 of the vehicle 100. The first door 106 is shown in its closed position in Fig. 16, at an intermediate position in Fig. 17 and in a fully open position in Fig. 18.

In the embodiment of Figs. 16 to 18, the actuation means 123 comprises two actuators 1601 and 1602. A first actuator 1601 is mounted within the cabin 103 on the body 101 of the vehicle 100 and a second actuator 1602 is mounted on the inside of the outer panel 1 10 of the front door 106. The first actuator 1601 comprises a first electric motor 1602 having an output shaft connected directly to a first connecting gear 1604 that is operatively engaged with a first drive gear 1605. The first drive gear 1605 is configured in a similar manner to the drive gear 813 of Figs. 8, 9 and 10 and has an internal bore through which is located a spindle 1606 defining a helical groove like the spindle 122 of Figs. 8, 9 and 10. Thus, operation of the first motor 1603 causes rotation of the drive gear 1605 and linear movement of the spindle 1606. An end of the spindle 1606 is pivotally connected to the second actuator 1602 by a pivot pin 1607 as shown in Fig. 16.

An upper portion of a housing 1609 of the second actuator 1602 has been omitted in Figs. 17 and 18, to show the internal components of the second actuator 1602. As in the previously described embodiment, the first door 106 comprises a spindle 122 fixed to its outer panel 1 10. The spindle 122 is similar to that of Figs. 8 and 9 and similarly extends through a bore of a second drive gear 813A, like the drive gear 813 of Figs. 8 and 9. However, in the embodiment of Figs. 16 to 18, the second drive gear 813A is driven by a second motor 1607 via a second connecting gear 1608. The second actuator 1602 is therefore configured to cause linear motion of the first door 106 relative to the second actuator 1602.

During opening from the closed position of Fig. 16, the control system 124 initially causes operation of the first motor 1603 which causes the front edge 303 of the outer panel 1 10 of the front door 106 to be pushed out from the doorway 105. The first actuator 1601 may be provided with one or more sensors (not shown) configured to determine its position and provide signals to the control system 124 indicative of when the door 106 has reached the intermediate position of Fig. 17. When the intermediate position has been reached, the first motor 1603 is stopped and the control system 124 outputs a signal to the second actuator 1602 to cause the second motor 1607 to drive the drive gear 813A and thereby cause linear motion of the spindle 122 through the drive gear 813A. In this way, the front door 106 is slid along the body of the vehicle 100 away from the doorway 105 to the fully open position of Fig. 18.

To cause closing of the first door 106 the process is reversed. Thus, the control system 124 initially causes operation of the second motor 1607 to cause the door 106 to be driven from the open position of Fig. 18 to the intermediate position of Fig. 17. The control system 124 then provides an output signal to cause operation of the first motor 1603 to drive the spindle 1606 through the drive gear 1605 to pull the front edge 303 of the first door 106 back into the doorway 105 to the closed position of Fig. 18.

In further alternative embodiments, the rails 122 of the doors 106 and 107 are supported by a guide member that is moveable by a first actuator, like actuator 1601 of Figs. 16 to 18, to cause the movement of the front edge 303 of the front door 106 and the rear edge 31 1 of the rear door 107 of from the doorway 105. However, the rails 122 are configured to slide on their guide members. Instead of the doors 106 and 107 having a second actuator that is configured to act on the rail 122, the doors have a second actuator that is mounted on the body 101 of the vehicle 100 and arranged to push the lower carriages 1 14 and 120, or the upper carriages 1 1 1 and 1 17, along their tracks 109A and 109B, or 108A and 108B, to cause the doors 106 and 107 to move between their partially open positions and their fully open positions.

A schematic diagram of the control system 124 shown in Figs. 1 and 2 is shown in Fig. 19. In the present embodiment the control system 124 comprises a single processor 1901 but, in other embodiments of the invention the control system 124 may comprise more than one processor 1901 . The control system 124 comprises at least one electronic memory device 1902, having instructions 1903 stored therein, and the electronic processor 1901 is electrically coupled to the at least one electronic memory device 1902, so that it can access the instructions 1903.

The control system 124 comprises an electrical input 1904 for receiving signals from both the user input devices 131 , indicative of requests to open and close the doors 106 and 107, and from sensors (not shown) used to monitor the positions of the doors during their movement. The control system 124 also comprises an electrical output 1905 for providing output signals to the actuation means 123 and 126 to cause opening and closing of the doors 106 and 107 as required. The processor 1901 is configured to access the instructions 1903 stored in the memory device 1902 and execute the instructions so that it is operable to perform the functions as described previously and as summarised in the flowchart of Fig. 20.

Fig. 20 shows a flowchart illustrating a method 2000 of controlling operation of two doors 106 and 107 of a vehicle 100.

At block 2001 of the method 2000, it is determined whether a signal has been received requesting that only a first door 106 or only a second door 107 is to be opened, and if so an output signal is provided at block 2002 to an actuator 123 or 126 to cause the requested door 106 or 107 to be opened. It may be noted that the other door 106 or 107 may be in a closed position and left in the closed position while the requested door 106 or 107 is opened.

At block 2003 it is determined a signal has been received requesting that both the first door

106 and the second door 107 be opened and if so then at block 2004 a signal is provided to cause simultaneous opening of both doors 106 and 107. If one door 106 or 107 is already open and one is currently closed, the door 106 or 107 that is currently closed may be caused to open at block 2004.

At block 2005 it is determined whether a signal has been received requesting that only the first door 106 or only the second door 107 be closed and if so, at block 2006, an output signal is provided to an actuator 123 or 126 to cause only the requested door 106 or 107 to be closed, if the requested door 106 or 107 is currently open. It may be noted that the other door 106 or

107 may already be closed when the requested door 106 or 107 is closed at block 2006.

At block 2007 it is determined whether a signal has been received requesting that both the first door 106 and the second door 107 be closed, and if so then an output signal is provided at block 2008 to cause simultaneous closing of the two doors 106 and 107 if they are both open. If one of the two doors 106 or 107 is already closed, the currently open door 106 or 107 may be caused to close at block 2008.

For purposes of this disclosure, it is to be understood that the control system described herein may comprise a control unit or computational device having one or more electronic processors. A vehicle and/or a system thereof may comprise a single control unit or electronic controller or alternatively different functions of the control system may be embodied in, or hosted in, different control units or controllers. A set of instructions could be provided which, when executed, cause said controller(s) or control unit(s) to implement the control techniques described herein (including the described method(s)). The set of instructions may be embedded in one or more electronic processors, or alternatively, the set of instructions could be provided as software to be executed by one or more electronic processor(s). For example, a first controller may be implemented in software run on one or more electronic processors, and one or more other controllers may also be implemented in software run on or more electronic processors, optionally the same one or more processors as the first controller. It will be appreciated, however, that other arrangements are also useful, and therefore, the present disclosure is not intended to be limited to any particular arrangement. In any event, the set of instructions described above may be embedded in a computer-readable storage medium (e.g., a non-transitory computer-readable storage medium) that may comprise any mechanism for storing information in a form readable by a machine or electronic processors/computational device, including, without limitation: a magnetic storage medium (e.g., floppy diskette); optical storage medium (e.g., CD-ROM); magneto optical storage medium; read only memory (ROM); random access memory (RAM); erasable programmable memory (e.g., EPROM ad EEPROM); flash memory; or electrical or other types of medium for storing such information/instructions.

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.

The blocks illustrated in the Fig. 20 may represent steps in a method and/or sections of code in the computer program 1903. The illustration of a particular order to the blocks does not necessarily imply that there is a required or preferred order for the blocks and the order and arrangement of the block may be varied. Furthermore, it may be possible for some steps to be omitted.

Although embodiments of the present invention have been described in the preceding paragraphs with reference to various examples, it should be appreciated that modifications to the examples given can be made without departing from the scope of the invention as claimed. For example although the actuators have been described as comprising an electric motor, it will be appreciated that in alternative embodiments at least some of the described actuation may be performed by pneumatic or hydraulic actuators. Also, the door arrangement has been described as being on a road vehicle, but it will be appreciated that the door arrangement could be implemented on another type of vehicle, such as a train, a plane, a ship, etc.

Features described in the preceding description may be used in combinations other than the combinations explicitly described.

Although functions have been described with reference to certain features, those functions may be performable by other features whether described or not. Although features have been described with reference to certain embodiments, those features may also be present in other embodiments whether described or not.

Whilst endeavoring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.