GB2487980A

GB2487980A - Bath with horizontally hinged door operated by a linear actuator

Info

Publication number: GB2487980A
Application number: GB1102512.9A
Authority: GB
Inventors: James Bruce Philip Charles Stuart-Smith; Peter Gerald Deverson
Original assignee: Astor Bannerman Medical Ltd
Current assignee: Astor Bannerman Medical Ltd
Priority date: 2011-02-12
Filing date: 2011-02-12
Publication date: 2012-08-15
Anticipated expiration: 2031-02-12
Also published as: GB2487980B; GB201102512D0

Abstract

The invention relates to a bath having a tub body 2 and comprises a door 3 which folds between a closed position against the tub body and an open position where it provides a substantially horizontal platform. A linear actuator 16 is pivotally connected to the bath body and is mounted by a mounting pin 17 to the door, whereby the actuator is linearly retracted and extended to move the door between its open and closed positions. The pin is not fixed to the door but movable in slots 15 substantially parallel to the plane of the door and is biased towards the pivot end of the door, preferably by means of a gas spring 20.

Description

F

BATH

The present invention relates to baths. More particularly it relates to baths having a downward-folding door to allow access.

There is already known a wide variety of baths which are designed to allow easier access for people with limited mobility. One such type of bath includes a door extending along a substantial portion of one side of the bath, which door folds down to provide a platform onto which a person may transfer themselves from a wheelchair. The bath will be set on a frame, which may provide height-adjustability, to ensure that the platform is at the correct height for an easy transfer from a wheelchair. The greater height of the bath is also an advantage to carers, who will be able to wash a bather without having to bend over as far as they would if the bath were at a conventional height.

The door on such baths may be manually or electrically operated. In the case of a manually operated door, a latching mechanism is used to hold the door closed. If an electric door is used, it is possible to operate it by means of a linear actuator. Provided the actuator is sufficiently powerful and cannot be back-driven, the actuator can be used to hold the door closed, including holding it closed with sufficient force to allow a watertight seal between the door and the bath body.

A problem arises with such actuator operated doors if the door is stopped before it is folded fully down. If a person transfers onto the door when it is not fully down, then very considerable forces are transferred through the actuator into the bath body and door. Likewise, it has been found that some people use the door to help to move themselves finally into the bath, raising the door electrically while their legs are still on it to roll or slide themselves into the bath. Once again, this can put undesirably large forces into the door and tub.

According to the present invention there is provided a bath having a tub body, a door which folds between a closed position against the tub body and an open position where it provides a substantially horizontal platform, a linear actuator connected to the bath body and pivotally mounted with mounting means to the door at a cranked point with respect to the axis of fold whereby to move the door between its open and closed positions as the actuator is linearly extended, characterised in that the said mounting means are not fixed to the door but movable substantially parallel to the plane of the door and are biased towards the fold end of the door.

Preferably the mounting means are able to move a distance equal to the full extension stroke of the said linear actuator.

Preferably the mounting means move in a slot in a member which slot is substantially parallel to the plane of the door.

Preferably the mounting means are biased towards the fold end of the door by means of a spring.

The invention will now be more fully described with the aid of the following drawings in which: Figure 1 shows a bath with a door of a known design in an open position Figure 2 shows the bath of Figure 1 with the door in the closed position Figure 3 shows in section the bath of Figure 1 with the door in a nearly open position Figure 4 shows a bath incorporating an embodiment of the invention, with the door in an open position Figure 5 shows in section the bath of Figure 3 with the door in a nearly open position Figure 6 shows the bath of Figure 3 with the door in a closed position Figure 1 shows a bath having a door of a known design. The bath comprises a stand 1, a tub body 2 and a door 3 which folds open and closed along an axis 4. In this example the bath is made of ABS which is reduced in thickness along the axis 4 to allow it to fold along that axis while still maintaining a completely waterproof seal. The door also has side panels 5 which have areas reduced in thickness to allow them to fold in an origami-like fashion to keep the bath watertight when closed.

The door of the bath includes ribs 7 which serve to stiffen and also to support it when it is folded down and being used as a platform to transfer a patient into the bath. It will be seen that in this lowered position the ribs 7 bear against the underside of the tub body 2, transferring the load of the patient evenly across the tub body. The centre pair of ribs 8 have holes 9 passing through them. An actuator 12 is positioned between the ribs 8 and a pin 10 passes through the holes 9 and through a corresponding hole in the inner piston 11 of the actuator, such that the actuator is pivotally attached to the ribs 8, providing a mount to the door cranked with respect to the axis 4. The other end 13 of the actuator 12 is pivotally attached to the underside of the tub body as shown.

Figure 2 shows the bath of Figure 1 once the actuator inner piston 11 has driven out, folding the door up to its closed position. The actuator is of the type that cannot be back-driven. As a result the door is held closed against any forces from inside the bath. To re-open the door, actuator is simply operated in the opposite direction.

Figure 3 shows the bath of Figure 1 with the door in a nearly-open position. In this position, the actuator inner piston 11 is driven out slightly and serves to hold the door at a few degrees to the horizontal. It will be seen that in this position any load on the door -and particularly if the door is used as a transfer platform -will impose very significant forces on the actuator, which will not be shared by the ribs. As the angle between the actuator and the door becomes more obtuse, these forces can become very significant indeed. Similarly, if a user tries to drive the door closed with a load on it -for example if the user tries to use the door to move their legs into the bath -the forces on the actuator and mount will be undesirably high in the early stages of movement when the door is nearly open.

Figure 4 shows a bath incorporating an embodiment of the invention. Once again, the bath comprises a stand 1, a tub body 2 and a door 3 which folds open and closed along an axis 4, with the bath made of ABS which is reduced in thickness along the axis 4 to allow it to fold along that axis while still maintaining a completely waterproof seal. The door of the bath also includes ribs 7 which serve to support it when it is folded down and being used as a transfer platform, which ribs bear against the underside of the tub body 2, transferring the load of the patient evenly across the tub body.

In this embodiment the centre pair of ribs 14 have slots 15 passing through them which slots run substantially parallel to the plane of the door. An actuator 16 is positioned between the ribs 14 and a mounting pin 17 passes through the respective slots and through a hole in the inner piston 19 of t the actuator. In this way, the actuator becomes pivotally mounted to the ribs -and thus the door -but the pivot point can move along the slots. However, a gas spring 20 is also mounted between the ribs 14. In the embodiment shown it is attached at one end to the door and at the other end is pivotally linked to the actuator inner piston 19 by means of an eye through which the pin 17 also passes. In this way the pivot point of the actuator with respect to the door is biased to be normally at the end of the slots nearest the axis of fold 4 of the door.

Figure 5 shows the bath of Figure 4 with the door in a nearly-open position with the actuator inner piston 19 driven out slightly and holding the door at a few degrees to the horizontal. It will be seen that in this position a load on the door will cause the mounting pin 17 to move along the slots 15 against the force of the gas spring 20 until the door is fully open and supported on the ribs. In this way excessive forces on the actuator and actuator mount are avoided. In a similar manner, it wilt be seen that if a user attempts to use the door to lift or move their legs, the force that it will be possible to apply will be limited by the force needed to overcome the gas spring. It will be noted that by adjusting the gas spring force, it is possible to tailor the door closure so that it can be used to give some assistance in moving a user but not enough to damage the actuator, door or tub.

Figure 6 shows the bath of Figure 4 with the door in a fully closed position, with the inner piston 19 of the actuator fully driven out. In this configuration the slots 15 are now perpendicular to the direction of force of the actuator and so pushing the door to try to open it will have no effect. The actuator is of a type that cannot be back driven so the door is held closed against any forces from inside the bath.

In this way the door is protected against excessive forces when in the open position while at the same time being held safely closed when in its closed position.

In the embodiment shown, the slots 15 are of a length such that the inner piston 19 can extend fully against the force of the gas sprint without moving the door when there is a load on it. Other embodiments can be envisaged, however, where the slots are shorter, giving protection against excessive force only for the first few degrees of movement of the door.

Other embodiments can be envisaged in which the slots are replaced by other means of retaining the mounting pin 17 or where the mounting pin and slot arrangement is replaced by another mounting means and another way of restraining its motion to one substantially parallel to the plane of the door. Similarly, other means besides a gas spring of biasing the mounting means towards the fold end of the door can be readily envisaged.

Claims

CLAiMS 1. A bath having a tub body, a door which folds between a closed position against the tub body and an open position where it provides a substantially horizontal platform, a linear actuator connected to the bath body and pivotally mounted with mounting means to the door at a cranked point with respect to the axis of fold whereby to move the door between its open and closed positions as the actuator is linearly extended, characterised in that the said mounting means are not fixed to the door but movable substantially parallel to the plane of the door and are biased towards the fold end of the door.
2. A bath as claimed in claim 1 wherein the mounting means are able to move a distance equal to the full extension stroke of the said linear actuator.
3. A bath as claimed in claim 1 or 2 wherein the mounting means move in a slot in a member which slot is substantially parallel to the plane of the door.
4. A bath as claimed in any preceding claim, wherein the mounting means are biased towards the fold end of the door by means of a spring.
5. A bath substantially as described hereinbefore, with reference to the drawings.