GB2303350A - Retractable Step - Google Patents

Description

RETRACTABLE STEP This invention relates to a retractable step for a vehicle, particularly a motor vehicle.

In some motor vehicles the floor can be relatively high off the ground, and an intermediate step may be needed by elderly or disabled people, to enable them to get into and out of the vehicle.

Such intermediate steps are often manually operated and simply comprise a platform which slides between retracted and advanced positions on brackets attached under the vehicle chassis. A disadvantage of such steps is that the vehicle can be driven with the step in its advanced position, which can be hazardous. Furthermore, the construction means that the platform and the brackets get dirty, so that the platform becomes difficult to operate.

According to the present invention, a retractable step for a vehicle comprises a platform slidable between advanced and retracted positions on support means attached to the vehicle adjacent a door, and has control means operative to ensure that the platform is movable into the advanced position only when the vehicle door is open, and to ensure that the platform is moved into the retracted position when the door is shut.

The invention therefore ensures that the platform cannot be in the advanced position when the door is shut, so that the vehicle will not normally be driven with the platform in the advanced position. This arrangement also helps to avoid the step becoming dirty.

The control means may be separate advance and retraction control means. Then, the advance control means ensures that the platform is movable into the advanced position only when the door is open, and the retraction control means ensures that the platform is moved into the retracted position when the door is shut.

Movement of the platform is preferably achieved by a power-operated actuator. The actuator may be electric, or of any other suitable type. Preferably it is a linear actuator. The control means then conveniently comprises one or more electric switches mounted in a jamb of the door. There may be an advance control switch arranged so that it can only be operated when the door is open, and a retraction control switch arranged so that it is operated automatically by the door as it shuts, thus automatically retracting the platform.

Alternatively, the platform may be moved manually. The control means may then comprise one or more abutments. For example, an advance control abutment may be disengageable only when the door is open to allow movement of the platform. Similarly, a retraction control abutment may prevent the door closing with the platform in the advanced position.

The support means preferably comprises a closed frame attached by brackets to the vehicle. The platform may be a tread mounted on a slide movable in the frame between the retracted and advanced positions. The actuator is mounted on the frame, and connected to the slide. This construction helps to avoid the ingress of dirt into the sliding parts and the actuator.

The frame preferably also has rollers for guiding the slide. It may also have low friction sliding surfaces, such as PTFE strips. This ensures that the platform slides easily, even after prolonged use.

An embodiment of the invention is illustrated by way of example in the accompanying drawings, in which: Figure 1 is a rear view of a retractable step for a vehicle; Figure 2 is a section along the line 2-2 of Figure 1 with a tread plate removed and the step in a retracted position; and Figure 3 is a section similar to that of Figure 2, but with the step in an advanced position.

The Figures show a retractable step 1 for a motor vehicle (not shown), adapted to be mounted adjacent a vehicle door to help people to get into and out of the vehicle. The step 1 comprises a platform 2 slidable between an advanced position (Figure 3) and a retracted position (Figure 2) on a support means 3 attached to the vehicle by brackets 4. The platform 2 is moved between the advanced and retracted positions by an electric actuator 5, operated from the vehicle battery in response to control means 6 mounted in the form of a pair of switches 7,8 in a jamb of the vehicle door.

The support means 3 comprises a substantially closed rectangular frame 9 having a base plate 10, sides 11 and top portions 12 along the sides 11.

The frame 9 is fabricated from metal and is bolted to the brackets 4 by bolts (not shown). The actuator 5, which is any suitable type of electric linear actuator, is mounted in the centre of the base plate 10, while three pairs of plastics guide rollers 13 are bolted to the frame 9, one of each pair being adjacent a respective side 11, to define a pair of tracks 14 in which the platform 2 slides.

Each track 14 is also provided with a PTFE guide strip 15.

The platform 2 comprises a tread member 16 of aluminium alloy tread plate, mounted on a slide 17.

The slide 17 is fabricated from steel, and has a main tubular portion bent into a U-shape 18. Each arm 19 of the U-shape 18 runs in a track 14 of the frame, and its free end 20 is closed by a plastics roller 21. A cross-piece 22 of smaller diameter tube is welded between the arms 19 to support the tread member 16, and a flat steel bar 23 is incorporated to connect the free end of the actuator 5 to the connecting portion 24 of the Ushape 18.

The switch 7 acts as an advance control switch which can only be operated when the door is open.

The switch 8 acts as a retraction control switch, and is operated by the closing of the door.

For operation, the switch 7 is operated following opening of the door to actuate the linear actuator 5 to advance the platform 2 relative to the frame 9, enabling the step to be used. The switch 8 is operated to actuate the linear actuator 5 to retract the platform 2 again. If the switch 8 is not operated manually with the door open, it will be operated automatically by the door as it closes, thus ensuring that the step is retracted when the door is shut. This means that the vehicle is unlikely to be driven with the platform 2 in the advanced position.

It will be appreciated that the rollers 13,21 and the PTFE guide strips 15 reduce friction and ensure that the slide 17 moves easily in the tracks 14. The construction of the frame 9 as a substantially closed member helps to prevent ingress of dirt into the sliding parts and the actuator 5.

In a modification (not shown) the two switches 7,8 may be replaced by a single twoposition switch.

In further modifications (not shown) the actuator may be of any other suitable type. It is also possible for the platform 2 to be manually operated. The actuator 5 would then be eliminated, and the switches 7,8 replaced by one or more abutments engaging with the door to act as the control means 6.

It will also be appreciated that a further aspect of the invention consists in a kit of parts for making a retractable step.

Claims (14)

1. A retractable step for a vehicle comprising a platform slidable between advanced and retracted positions on support means attached to the vehicle adjacent a door, and control means operative to ensure that the platform is movable into the advanced position only when the vehicle door is open, and to ensure that the platform is moved into the retracted position when the door is shut.

2. A retractable step according to Claim 1, in which the control means comprises separate advance and retraction control means.

3. A retractable step according to Claim 1 or Claim 2, incorporating a power-operated actuator for moving the platform between the advanced and retracted positions, in which the control means comprise separate advance and retraction means for controlling operation of the actuator.

4. A retractable step according to Claim 3, in which the actuator comprises a linear actuator.

5. A retractable step according to Claim 3 or Claim 4, in which the actuator is electric, and the control means comprises at least one electric switch mounted in a jamb of the door.

6. A retractable step according to Claim 5, in which an advance control switch is arranged to be operated only when the door is open, and a retraction control switch is arranged to be operated by the door as it shuts.

7. A retractable step according to Claim 1 or Claim 2, in which the platform is moveable manually, and the control means comprises one or more abutments.

8. A retractable step according to Claim 7, in which the control means comprises an advance control abutment disengageable only when the door is open to allow movement of the platform, and a retraction control abutment to prevent the door closing with the platform in the advanced position.

9. A retractable step according to any preceding claim, in which the support means comprises a frame attached to the vehicle, and the platform comprises a tread mounted on a slide movable in the frame between the advanced and retracted positions.

10. A retractable step according to Claim 9, in which the slide is guided on rollers in the frame.

11. A retractable step according to Claim 9 or Claim 10, in which the frame is provided with low friction guiding surfaces for the slide.

12. A retractable step for a vehicle comprising a frame, a tread mounted on a slide movable in the frame between advanced and retracted positions, mounting means for attaching the frame on a vehicle adjacent to a door, and means adapted to co-operate with the door to ensure that the platform can only be moved into the advanced position after the door has been opened, and to ensure that the door cannot be shut until after the platform has been returned to the retracted position.

13. A retractable step for a vehicle as claimed in Claim 12, in which an actuator for moving the tread between the advanced and retracted positions is also mounted on the frame.

14. A retractable step substantially as described herein with reference to and as illustrated in the accompanying drawings.