GB2351268A

GB2351268A - A carriage for ascending or descending stairs whilst carrying a seated person or suitably restrained goods

Info

Publication number: GB2351268A
Application number: GB0014757A
Authority: GB
Inventors: Barry Martin Scholes
Original assignee: Paraid Ltd
Current assignee: Paraid Ltd
Priority date: 1999-06-23
Filing date: 2000-06-19
Publication date: 2000-12-27
Also published as: GB0014757D0; GB9914536D0

Abstract

A carriage for ascending or descending stairs (10) whilst carrying a seated person or suitably restrained goods under the control of an operator is described. The carriage (10) includes a main frame (12) having at least one member (13) extending longitudinally of the carriage, and a handle (14) by which the operator may control the carriage; a platform (18, 19, 20) for carrying the seated person or goods; a powered mechanism (22) itself comprising a drive train having an electric motor (23) and a gear box (24), with power supplied by a battery (25) for ascending or descending stairs depending on it's direction of operation; and a gravitational descent mechanism (40) that includes an endless belt that is mounted on and passes round a pair of rollers (not shown).

Description

2351268 PATENTS ACT 1977 A1000OGB-DMW Title: Carriage for ascending or

descending stairs whilst carrying a seated person or suitably restrained goods.

Description of Invention

This invention relates to a carriage for ascending or descending stairs carrying a seated person or suitably restrained goods under the control of an operator.

Many people work or live at high elevations in buildings, and because of one disability or another are unable to traverse stairs, normally relying on elevators in the building for moving from floor to floor. However, fire services suggest that in the case of fire, or other emergency, elevators should not be used. Therefore, the stairs must be relied upon as the sole means of escape from the building in any such emergency. Alternatively, after hospitalisation or other treatment, patients require returning to their homes, and when domiciled at above ground level, may need to be physically carried to their home, in the absence of elevators. Rules may be introduced by the authorities to limit the weight of persons or goods carried by an employee. In most circumstances requiring the movement of persons, there are able-bodied people available who can assist those who require help. The present invention relates to a carriage that will facilitate such help and allow the raising or lowering of weights exceeding the weight limit for lifting imposed by the authorities up and down stairs.

According to the present invention a carriage for ascending or descending stairs carrying a seated person or suitably restrained goods under the control of an operator is provided which includes:

2 a main frame having at least one member extending longitudinally of the carriage, and a handle by which the operator may control the carriage; a platform for carrying the seated person or goods; a powered mechanism for ascending or descending stairs depending on it's direction of operation, and a gravitational descent mechanism.

Preferably both the powered mechanism and the gravitational descent mechanism are selectively operable.

The powered mechanism may include a drive train having an electric motor and a gearbox, two endless loops carrying lifters and driveable by the drive train around elongate paths extending longitudinally of the carriage to each side of it's longitudinal axis and defined by spaced apart pairs of rollers, the lifters being engageable in use with the nose of a stair to lift the carriage up the height of the stair tread or lower it down depending on the direction of motion of the lifters.

Conveniently the endless loops are formed of chain.

The gravitational descent mechanism may include two endless loops around elongate paths extending longitudinally of the carriage to each side of it's longitudinal axis and defined by spaced apart pairs of rollers, the endless loops when in operation being in contact with the stair and providing ffictional braking.

The carriage preferably further includes rotatably mounted ground engaging wheels for movement along the ground.

Preferably the carriage is foldable for storage.

In order that the invention may be better understood a preferred embodiment will now be described, by way of example only, with reference to the accompanying drawings, in which:- FIGURE 1 is a side elevation of the carriage with the gravitational descent device deployed; 3 FIGURE 2 is a side elevation of the carriage showing the operating position for the powered ascent/descent device and the gravitational descent device stowed; FIGURE 3 is a side elevation of the carriage showing the configuration for wheeling along the ground; FIGURE 4 is a front view of the carriage as shown in Figure 1, and FIGURE 5 is an enlarged sectional view on the line 5-5 of Figure 1.

A stair carriage 10 includes a main frame 12 which extends longitudinally of the carriage 10. The main frame 12 comprises two spaced apart parallel main longitudinal members 13, which define the width of the carriage 10, and a handle 14 located at the top end thereof for use by the operator of the carriage. The handle 10 also serves to add rigidity to the frame 12. The main frame 12 further comprises two cross members 15, 16 extending laterally between the two main longitudinal members 13 to provide further rigidity. Two primary ground engaging wheels 17 are provided, one at the bottom end of each main longitudinal member 13. These primary ground engaging wheels 17 have brake mechanisms 17,a of known kind, which comprise a frame 17b pivotally secured to the axle on which each of the primary ground engaging wheels 17 rotates, which carries a brake bar 17c in a middle position and a secondary wheel 17d towards it's distal end. The frame 17b moves under gravity to engage the brake bar 17si on the primary ground engaging wheel 17 when the secondary wheel 17d is not on the ground, but if the secondary wheel 17d is also engaged with the ground this lifts the brake bar 17c off the primary ground engaging wheel 17 permitting it to rotate. If necessary the frame 17b may be spring biased, to bring the brake bar 17p into contact with the primary ground engaging wheel 17, when the secondary wheel 17d is not on the ground. The operation of this feature, which acts as a stair nose sensing device, will be described below.

4 A platform, in this case a seat IS for a person, is pivotally connected to the main longitudinal members 13 below the midpoint thereof The seat 18 may be pivoted down into the use position shown in Figures I and 2 independently of any other feature of the carriage 10. A safety belt 19 is provided to secure the person carried by the carriage 10 into the seat 18, but may also be used to secure the seat 18 in it's folded position when it is extending substantially parallel with the main longitudinal member 13. A seat back 20 is connected between the main longitudinal member 13 above the pivotal connection of the seat 18, this adds further rigidity to the frame 12, whilst also giving the person carried in the carriage a back support.

The carriage 10 also includes a powered ascent or descent mechanism 22 located between the main longitudinal members 13 towards the bottom ends thereof. The powered mechanism 22 includes a drive train having an electric motor 23 and a gear box 24, with power supplied by a battery 25. For ease of use the battery 25 has a quick release mechanism, which for brevity will not be described in detail here, making it quick and simple to remove one battery for re-charging and replace it with another.

The gear box 24 is drivingly connected to an axle 26 which extends across the carriage 10 between and substantially perpendicular to the main longitudinal members 13, and which carries a cogged drive wheel 27, or sprocket, on each end. The axle 26 passes through a support plate 28 on each side of the drive train, which extend substantially parallel to the main longitudinal members 13 towards the bottom end thereof Cogged free wheels 29 are rotatably secured to the lower ends of the support plates 28 in the same plane as the cogged drive wheels 27.

The cogged drive wheels 27 and cogged free wheels 29 on each side of the drive train provide a path for an endless loop of chain 30. Each endless loop of chain 30 carries fixed to it equally spaced apart two hook formations 31 which act as lifters, as will be described below. The hook formations 31 carry bearing surfaces 3 1 a which may of any appropriate material, which must be hardwearing, non-marking and provide reasonable friction between the bearing surfaces and the stairs to be ascended or descended.

The shape and size of the lifters 31 is determined by the location of the endless loops of chain relative to the primary ground engaging wheels 17, and to the location of the drive train relative to the other parts of the carriage 10. Clearly the lifters 31 when moving around with the chains 30 must be able to pass unhindered around the paths of the chains, other then when they come into contact with a stair.

The powered mechanism 22 has very simple controls, not shown, which permit the operator to select it for operation, and when operating for driving the endless loops 30 in either direction, as required for ascending or descending stairs.

The powered ascent and descent mechanism 22 operates as follows when ascending. The carriage 10 should be in the configuration shown in figure 2. In this configuration, when the primary ground engaging wheels 17 are on the ground, and as the secondary wheels 17d of the brake mechanism 17a are also on the ground, the brake mechanism 17a is released and the carriage 10 can be pulled on the primary ground engaging wheels 17 towards the riser of the stair to be climbed. The powered mechanism 22 is operated in ascending mode which drives the chains 30 such that the lifters 31 travel downwards on the outside of the rear of the carriage 10. When the lifters 31 contact the nose of the stair and the drive continues, then as they travel down with respect to the carriage 10, they are held stationary by the stair and the carriage is raised up to the tread at the next level. The carriage 10 is then pulled by the operator towards the next stair riser, and so on up the stairs.

When descending the operation is similar, but the powered mechanism 22 is operated to drive the chains 30 in the opposite direction such that the lifters 31 travel upwards on the outside of the rear of the carriage 10. As the 6 carriage 10 is pushed towards the edge of the tread of a stair, the secondary wheel 17d of the brake mechanism 17a falls off the nose of the stair first, causing the brake mechanism 17a to operate against the primary ground engaging wheels 17. This halts the forward progress of the carriage 10, and the lifters 31 moving downwards within the carriage 10 come into contact with the tread of the stair, as they continue their movement relative to the carriage, but cannot move further down, the carriage 10 is lifted up and moved forwards towards and over the nose of the stair. As the movement of the lifters continues up the outside of the carriage 10, the carriage 10 is lower from the stair on which it started to the tread of the next stair down the flight. The process is then repeated until the bottom of the flight is reached.

The carriage 10 further comprises a gravitational descent mechanism 40. This is conveniently of the form described in GB 2 111 001 B, and will be described briefly. The gravitational descent mechanism 40 comprises a pair of runners 4 1, one located on each side of the carriage 10. Each runner 41 has (as best seen in Figure 5) a channel member 42, which provides an upper channel 43, a lower channel 44, an upper wall 45, and a slot 46 adjacent the upper wall 45. A pair of rollers (not shown) is provided, one at each end of the channel member 42. An endless belt 47 has an upper run 48 and a lower run 49 and is mounted on and passes around the pair of rollers.

The channel members 42 are pivotally connected to the carriage 10, adjacent their lower ends, close to the primary ground engaging wheels 17. They are further connected to the carriage by means of a pair of struts 50, each of which is pivotally connected at one end to one of the main longitudinal members 13 close to the pivotal connection of the seat 20. The other end of each strut 50 is slidably connected to a channel member 42 by means of a pin 51 which runs in the slot 46, and in doing so helps to retain the belt 47 within the channel member 42, as described below. A handle (not shown) is provided secured to each channel member 42 to enable an operator to pull the runners 7 from their folded configuration (as shown in figure 2) to their operative configuration (as shown in Figure 1), it also adds rigidity to the gravitational descent mechanism.

The upper run 48 of each belt 47 runs in the respective upper channel 43. The lower run 49 of each belt 47 runs in the respective lower channel 44. The belts 47 are formed of a base of high friction fabric 47a adjacent the upper and lower channels, and a bonded strip of flexible rubber 47b.

The gravitational descent mechanism operates as follows. When the runners are in the operative configuration, and it is on a flight of stairs, the belts 47 are in contact with the noses of at least two stairs at once, as shown in Figure 1. Because of the nature of the rubber 47b of the belts 47 the belts remain stationary on the stairs whilst the channel members 42 move relative to them, but that movement is itself inhibited to some extent by the friction between the belts 47 and the channel members 42. Thus the operator holding the handle 14 does not have to take all the weight of the carriage 10 and it's load.

The carriage 10 can also be used to push the load along reasonably flat ground once the stairs have been safely negotiated. To enable this a pair of secondary ground engaging wheels 60 is provided pivotally secured to the runners 40. A foot engagable release mechanism (not shown) is provided between the two secondary ground engaging wheels 60 to assist the operator in bringing them down into use. To obtain the carriage configuration for ground use the runners 40 must be in their operative position and then the secondary ground engaging wheels 60 are also folded down.

For storage the carriage 10 can be folded completely such that it is very compact. This is the runners 40 are folded in, as shown in Figure 2, as are the secondary ground engaging wheels 60, and the seat 18 is folded up substantially parallel with the main longitudinal members 13, and preferably retained there by the safety belt 19.

8 The brake mechanism 17a described above is just one example of a suitable mechanism providing the required braking and stair nose sensing, carriages according to the invention may incorporate any suitable brake and nose sensing mechanism.

Although the carriage 10 has been described above with a seat 18, if the carriage is for movement of goods rather than a person, the seat may be replaced with any other form of platform as appropriate for that use.

The endless loops of the powered mechanism 22 need not be in the form of chains 30. They may be of any appropriate form for the application, e.g. nylon belts carrying lifters.

In the present specification "comprise" means "includes or consists of' and "comprising" means "including or consisting of'.

The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims

9 CLAIMS

1. A carriage for ascending or descending stairs whilst carrying a seated person or suitably restrained goods under the control of an operator, includes: a main frame having at least one member extending longitudinally of the carriage, and a handle by which the operator may control the carriage; a platform for carrying the seated person or goods; a powered mechanism for ascending or descending stairs depending on it's direction of operation, and a gravitational descent mechanism.

2. A carriage according to claim 1 wherein both the powered mechanism and the gravitational descent mechanism are each selectively operable.

3. A carriage according to claim 1 or 2 wherein the powered mechanism includes a drive train having an electric motor and a gearbox, two endless loops carrying lifters and driveable by the drive train around elongate paths extending longitudinally of the carriage to each side of it's longitudinal axis and defined by spaced apart pairs of rollers, the lifters being engageable in use with the nose of a stair to lift the carriage up the height of the stair tread or lower it down depending on the direction of motion of the lifters.

4. A carriage according to claim 3 wherein the endless loops are formed of chain.

5. A carriage according to any preceding claim wherein the gravitational descent mechanism includes two endless loops around elongate paths extending longitudinally of the carriage to each side of it's longitudinal axis and defined by spaced apart pairs of rollers, the endless loops when in operation being in contact with the stair and providing frictional braking.

6. A carriage according to any one of the preceding claims which further includes rotatably mounted ground engaging wheels for movement along the ground.

7. A carriage according to any one of the preceding claims which is foldable for storage.

8. A carriage substantially as herein before described with reference to the accompanying drawings.

9. Any novel feature or novel combination of features described herein and/or in the accompanying drawings.