WO2018074936A1

WO2018074936A1 - A side rail

Info

Publication number: WO2018074936A1
Application number: PCT/NZ2017/050137
Authority: WO
Inventors: Anthony John Batley; Kevin Charles FISHER; Bruce Norton Moller
Original assignee: Howard Wright Limited
Priority date: 2016-10-19
Filing date: 2017-10-19
Publication date: 2018-04-26

Abstract

A compact, foldable side rail for a bed comprising an upper part (120) and a lower part (130) that are hinged together at a first pivot (150). The side rail is attached to a bed by a positioning system that causes the lower part of the side rail to fold toward the upper part and allows the upper part to lie in substantially the same plane as it is raised and lowered. The side rail includes a locking mechanism. The positioning mechanism comprises an upper part pivot arm (140) that attaches to the upper part via a second pivot (126) and attaches to the bed via a third pivot (127); and a lower part pivot arm (141) fixedly attached to the lower part (130) and that attaches to the bed via a fourth pivot (128).

Description

A SIDE RAIL

TECHNICAL FIELD

The present invention relates to a side rail for a bed, such as a hospital bed or nursing care bed.

BACKGROUND OF THE INVENTION

Side rails are commonly attached to the sides of hospital beds and nursing care beds to prevent patients falling out of bed. The bed typically comprises a frame supporting a deck on which a mattress platform is located. Often, the deck is able to be angled relative to the frame. Typically, the frame, and therefore the deck and mattress platform, can be raised and lowered. In some forms, the frame may also be configured to tilt. However, the configuration of many known side rails provides entrapment points where a patient's arm, neck, or other parts of the body may become trapped between the side rail and bed . The risk of being trapped in entrapment points is increased as the side rail is raised and lowered or as the bed or bed head is tilted from one position to another, such as between a flat position and Fowler's position, where the head of the bed may be elevated 45° .

Another problem with some known side rails for beds is that, even when lowered, the top edge of the side rail protrudes above the mattress platform of the bed, making it awkward and uncomfortable for a patient to get out of bed.

The main reason for the protruding top edge is that it is a requirement to provide foot clearance between the bottom edge of the side rail and the floor when the bed is fully lowered. The extent to which the mattress platform of a bed can be lowered is therefore limited by the side rails of the bed because the lowered side rails project below the mattress platform. The non-compact configuration of known side rails is such that if the top edge of the side rail was lowered below the mattress platform of the bed, the bottom edge of the side rail would adversely raise the minimum low height of the bed to avoid the side rail coming into contact with the floor. It is therefore desirable to provide a side rail for a bed that goes at least some way towards overcoming the disadvantages of the prior art or that at least provides the public with a useful choice.

SUMMARY OF THE INVENTION

In a first aspect, the invention provides a two-part side rail for a bed, the side rail being configured to move between a raised position and a lowered position, wherein the side rail comprises: a body comprising an upper part and a lower part that is hinged from the upper part; and a positioning mechanism. The positioning mechanism comprises: an upper part pivot arm comprising a first end that attaches to the upper part via a first pivot joint, and a second end that attaches to the bed via a second pivot joint; and a lower part pivot arm comprising a first end that is fixedly attached to the lower part, and a second end that attaches to the bed via a third pivot joint. In this configuration the step of lowering the side rail causes the upper part pivot arms to pivot downwardly to allow the upper part of the side rail to move downwardly to a point of maximum movement, while simultaneously, the lower part pivot arm pivots downwardly to allow the lower part of the side rail to move downwardly to a point of maximum movement and to cause the lower part to fold towards the upper part.

Preferably, the upper and lower parts are of substantially the same length and the lower part comprises a top edge configured to substantially correspond to a bottom edge of the upper part. In one form, the lower part is substantially in the form of a panel.

In one form, the positioning mechanism comprises an internal pivot arm forming the lower part pivot arm and a pair of external arms forming upper part pivot arms. The lower part pivot arm is located between the upper part pivot arms. The second ends of the upper and lower part pivot arms are attached to the bed via a mounting bracket. In this form, the second and third pivot joints are located on the mounting bracket. Preferably, the second pivot joint is located on the mounting bracket below the third pivot joint. In one form, the internal arm is configured to nest within the external arms. Preferably, the lower part pivot arm is configured to substantially fill a gap between the upper part pivot arms that are spaced apart from each other.

Preferably, the lower part and upper part pivot arms are angled toward the mounting bracket. Alternatively, the lower part and upper part pivot arms may be curved toward the mounting bracket.

In one form, the positioning mechanism is attached to the side rail at an area that is substantially central along the length of the side rail.

Optionally, the side rail further comprises a locking system to lock the pivot arms when the side rail is in a raised position and to unlock the pivot arms to allow the side rail to be lowered to a lowered position, wherein the locking system comprises a locking member located on the lower part pivot arm and a receiving member that is attached to at least one of the upper part pivot arms at a pivot joint and that engages with the locking member to lock the side rail in a raised position and disengages from the locking member to unlock the side rail. In one form, the receiving member comprises a pivoting latch and the locking member comprises a locking arm configured to be received within a recess or opening of the latch. Preferably, the locking system comprises a compression member configured to press the receiving member against the locking member. Optionally, the side rail further comprises an actuator connected to the receiving member and arranged to pivot the receiving member toward and away from the locking member to engage and disengage the locking member and receiving member respectively.

In one form, the side rail comprises one or more sensors configured to generate an electric signal when the side rail moves between a raised position and a lowered position and a control system configured to receive signals from the one or more sensors to identify whether the side rail is in a raised position or a lowered position and to control the minimum height to which a bed bearing the side rail can be lowered depending on the identified position of the side rail.

In a second aspect, the invention provides a bed comprising a frame supporting a bed deck supporting a mattress platform, wherein the bed comprises at least one side rail having the features described in relation to the first aspect of the invention. Preferably, the side rail is attached to the bed deck.

Also disclosed herein is a side rail for a bed, the side rail being configured to move between a raised position and a lowered position, and the side rail comprising a body comprising an upper part and a lower part, wherein the lower part is hinged from the upper part and is configured to fold toward the upper part when the side rail is lowered and wherein the upper and lower parts are of substantially the same length and the lower part comprises a top edge configured to substantially correspond to a bottom edge of the upper part.

In one form, the lower part is substantially in the form of a panel. In another form, both the upper and lower parts are in the form of a panel.

Preferably, the side rail further comprises a positioning mechanism comprising an internal arm and a pair of external arms, the internal arm being positioned between the external arms, wherein one end of each external arm is attached to the upper part of the side rail via a first, hinged joint and the other end of each external arm is attached to the mounting bracket via a second, hinged joint, and wherein one end of the internal arm is attached to the lower part of the side rail via a third joint and the other end of the internal arm is attached to a mounting bracket via a fourth, hinged joint.

In one form, the fourth hinged joint is located on the mounting bracket above the second hinged joint.

Preferably, the internal arm is configured to nest within the external arms. Optionally, the internal arm is configured to substantially fill the gap between the external arms.

Preferably, the internal and external arms are angled toward the mounting bracket. In one form, the internal and external arms are curved toward the mounting bracket.

Any reference to prior art documents in this specification is not to be considered an admission that such prior art is widely known or forms part of the common general knowledge in the field.

As used in this specification, the words "comprises", "comprising", and similar words, are not to be interpreted in an exclusive or exhaustive sense. In other words, they are intended to mean "including, but not limited to". As used in this specification, the term "side rail" refers to any safety side, cot side, rail, panel, or other system placed beside a bed to help prevent a person falling out of the bed. BRIEF DESCRIPTION OF THE FIGURES

Preferred embodiments of the invention will now be described by way of example only and in relation to the following drawings in which :

Figure 1 is a perspective view of one form of care bed comprising side rails according to one form of the invention;

Figure 2 is an isometric front view of a side rail in a raised position according to one form of the invention ;

Figure 3 is a side view of the side rail of Figure 2;

Figure 4A is a front view of the side rail of Figure 2 in a raised position;

Figure 4B is a rear view of the side rail of Figure 2 in a raised position;

Figure 5 is an isometric front view of the side rail of Figure 2 in a lowered position;

Figure 6 is a front view of the side rail of Figure 2 in a lowered position;

Figure 7 is a side view of the side rail of Figure 2 in a lowered position;

Figure 8 is a rear view of the side rail of Figure 2 in the lowered position;

Figure 9A is a cross-sectional view of one form of side rail showing one form of locking system of the invention in a locked position;

Figure 9B is a cross-sectional view of a similar side rail to that of Figure 9A, showing the locking system in an unlocked position ;

Figure 10A is a cross-sectional side view of one form of side rail in a raised position and showing possible locations of sensors for sensing whether the side rail is in the raised position or lowered position ; and

Figure 10B is a view of the side rail of Figure 10A in a lowered position.

DETAILED DESCRIPTION

As shown in Figure 1, a care bed 1000 (such as a hospital bed or aged care bed) typically comprises a frame, a substantially rectangular deck 550, and a mattress platform 600 on which a mattress is located. The mattress platform 600 is supported by the deck 550, which is attached to and supported from below by the frame 500. The frame may comprise: a central stand that is located substantially centrally with respect to the deck; a pair of legs located at each end of the deck; or at least four legs, in which at least one leg is substantially located at each of the four corners of the deck. The frame 500 suspends the deck 550 above the ground or floor and may comprise an elevator system (which is typically powered by a control system) configured to allow the deck 550 to be raised and lowered in relation to the ground/floor. The frame 500 may also be configured to allow the bed deck 550 to tilt between the Trendelenburg and reverse Trendelenburg positions. In some forms, the mattress platform 600 may comprise two or more portions configured to move relative to each other. For example, the mattress platform 600 may comprise a first portion that may tilt to form an angled backrest 600a. The mattress platform 600 may comprise a second, central portion or seat portion 600b that may be fixed to the deck and that substantially aligns with a patient's posterior when a patient lies on the bed. The mattress platform 600 may comprise a third portion, such as an upper leg raise portion 600c that may tilt to provide an upwardly angled thigh support. The bed deck may comprise a fourth portion, such as a lower leg raise portion 600d that may tilt to provide a downwardly angled lower leg support.

The invention generally relates to a compact, foldable side rail that provides a safety device to help prevent a person falling out of a bed. The side rail may be configured to allow the bed deck and therefore the mattress platform to be lowered to a relatively low height with respect to the floor, whilst providing foot clearance even when the side rail is in the lowered position. In a preferred form, the bed comprises a control system that allows the mattress platform to be lowered to a distance of about 340mm from the floor when the side rail is raised. In this position, when the side rail is subsequently lowered (a manual movement), the bottom edge of the side rail may be located at a distance of about 20mm from the floor. Alternatively, when the bed is in a raised position and the side rail is in the lowered position, the control system limits the minimum height to which the mattress platform may be lowered to a distance of about 400mm from the floor. In this position, the bottom edge of the side rail is at a distance of about 80mm from the floor. The control system is configured to identify the position of the side rail and to control the minimum height of the bed based on the identified position of the side rail. In this configuration, it is possible to avoid the risk that the bottom edge of the side rail is power driven (by the powered bed) onto a person's foot trapped between the side rail and the floor. Thus, the control system provides a useful safety mechanism.

Even when the bed is fully lowered and the side rail is also lowered, the compact side rail of the invention is configured so that the top edge of the side rail is located slightly above, or substantially at, or below the height of the mattress platform. This allows an occupant of the bed to easily exit the bed or get onto the bed when the side rail is in the lowered position. By providing a gap of between about 20mm and about 80mm between the floor and the bottom edge of the side rail, the side rail configuration provides sufficient foot clearance to reduce the risk that a person's foot could be trapped between the side rail and the floor whilst at the same time allowing the side rail to be sufficiently lowered below the mattress to allow an occupant of the bed to easily exit or get onto the bed.

Figures 2 to 10B show various forms of side rail 100 according to the present invention. The side rail is configured to attach to the side of a bed and to move between a raised position and a lowered position. The side rail may substantially extend along the length of the bed or the side rail may extend along only a portion of the length of the bed. For example, one side rail may be located along a first portion of the bed, extending between the top of the bed to the centre of the bed and another side rail may be located along a second portion of the bed, extending between the centre of the bed and the foot of the bed. A side rail may be located on only one or both sides of the bed. The side rail of the invention may optionally be located at the foot of the bed to form a foot rail.

The side rail 100 of the invention comprises a body 110 that is formed in two parts - an upper part 120 and a lower part 130. Both upper and lower parts 120, 130 comprise a front surface, being the surface that faces away from the bed, and an inner or rear surface that faces toward the bed. Each of the upper and lower parts also comprise a first or top edge and a second or bottom edge. It should be noted that, for each part, the first/top edge is located above the second/bottom edge when the side rail is a in a raised position. However, when the side rail is in the lowered position, the first/top edge of the lower part is located below the second/bottom edge of the lower part, due to the lower part folding up when the side rail is lowered. Each of the upper and lower parts of the side rail also comprise a left side edge and a right side edge.

The side rail itself comprises the same features. For example, the front surfaces of the upper and lower parts form the front surface of the side rail generally. In other words, the 'front' of the side rail is the side/face of the side rail that faces away from the bed platform. Likewise, the inner/rear surfaces of the upper and lower parts form the inner/rear surface of the side rail. The top edge of the upper part forms the top edge of the side rail and the bottom edge of the lower part forms the bottom edge of the side rail when in the raised position. In the lowered position, the bottom edge of the upper part or the top edge of the lower part or both may form the bottom edge of the side rail. The left and right side edges of the upper and lower parts form the left and right side edges of the side rail generally.

The length of the upper and lower parts 120, 130 may be substantially equal. In this configuration, the side rail body may have a substantially continuous perimeter. Alternatively, the upper part 120 of the side rail may be longer than the lower part 130 or the lower part 130 may be longer than the upper part 120. The height of the upper and lower parts 120, 130 (i.e. the distance from the bottom edge of that part to the top edge of that part) may also be substantially equal or one part 120, 130 may have a greater height than the other.

In one form, the lower part 130 of the side rail is attached to the upper part 120 via a folding mechanism comprising a hinged joint, which is also referred to in this specification as a first pivot joint 150. Preferably, a first pivot joint is provided at each of the left and right sides of the side rail to stably attach the lower part of the side rail to the upper part. The first hinged/pivot joint 150 is configured to allow the lower part 130 to hinge or fold toward the upper part 120 when the side rail 100 is lowered. In the folded configuration, the inner surface of the lower part substantially faces the inner surface of the upper part. The side rail 100 may also comprise a positioning mechanism 140 configured to control movement of the side rail as it is lowered and raised. In one form, the positioning mechanism is modelled on a four bar link system. The positioning mechanism 140 may comprise at least two pivot arms configured to attach the side rail to a bed, such as to a mounting bracket on a bed. The side rail may be directly attached to the bed deck or any other suitable location on the bed.

The mounting bracket may be attached to or integrally formed with part of the bed. For example, the mounting bracket may be attached or integrally formed with the bed deck. Alternatively, the mounting bracket may be located on the bed frame, or to any other suitable location on the bed. In another form, the mounting bracket may be indirectly attached to the bed, such as by being attached to a bracket support that is attached to the bed at any suitable location, such as to the deck or bed frame for example.

In one form, the side rail may comprise a pair of pivot arms to attach the side rail to the mounting bracket. Because the mounting bracket is integral with or is attached to the bed, each pivot arm extends between the rear surface of the side rail and the bed. A first of the two pivot arms attaches the upper part of the side rail to the bed and is referred to in this specification as the upper part pivot arm. The second of the two pivot arms attaches the lower part of the side rail to the bed and is referred to in this specification as the lower part pivot arm. Each pivot arm allows the respective upper and lower parts of the side rail to pivot about a respective pivot joint on the mounting block or bed as the side rail is raised and lowered.

In one form, the positioning system comprises three pivot arms: an internal pivot arm 141 located between a pair of external pivot arms 142a, 142b. In one form, the pivot arms are located substantially centrally along the length of the side rail. The pivot arms are preferably the same length.

The positioning system is configured to allow the lower part of the side rail to fold toward the upper part when the side rail is lowered. The positioning system may also be configured to allow the upper part to lie in substantially the same vertical plane as it is raised and lowered.

In one form, as illustrated, each external pivot arm 142 forms an upper part pivot arm and is configured to attach to the upper part 120 of the side rail 100, either directly or indirectly, via a second hinged/pivot joint 126. In one form, the upper part 120 of the side rail comprises a mounting region for attaching to the positioning mechanism. In one form, the mounting region 125 may comprise a mounting block that extends from the bottom edge 122 of the upper part 120 and is substantially centrally located along the length of the upper part, as shown best in Figures 2, 5 and 6. The mounting region/block 125 is configured to attach to end of each external/upper part pivot arm 142a, 142b via the second hinged/pivot joint 126, as shown best in Figures 2, 3 and 7. The opposite, second end of each upper part/external pivot arm 142 is attached to a mounting bracket 143 via a third hinged/pivot joint 127 that is located on the mounting bracket, as shown best in Figures 2, 3, and 7, so that the upper part pivot arms 142 are each able to pivot about the respective third pivot joint 127.

In one form, the internal/lower part pivot arm 141 is also attached to the mounting region/block 125 of the side rail, preferably through a fixed attachment so that the pivot arm 141 and lower part 130 move together when pivoting about the first hinged joint 150. For example, a first end of the lower part pivot arm 141 may be fixedly attached to the lower part of the side rail. In one form, the first end of the lower part pivot arm 141 attaches to the bottom edge 132 of the lower part 130. In one form, the lower part pivot arm 141 may be integrally formed with the lower part 130 to form a single component. In one form, a second, opposite end of the lower part pivot arm 141 is attached to the mounting bracket 143 or bed at a fourth hinged/pivot joint 128 that is located on the mounting bracket, as shown in Figure 3, so that the lower part pivot arm is able to pivot up and down about the fourth pivot joint 128. Preferably, the third pivot joint is located on the mounting bracket at a vertical distance below the fourth pivot joint.

In this configuration, the step of lowering the side rail causes the upper part pivot arms to pivot downwardly to allow the upper part of the side rail to move downwardly to a point of maximum movement. Simultaneously, the lower part pivot arm pivots downwardly to allow the lower part of the side rail to move downwardly to a point of maximum movement and to cause the lower part to fold towards the upper part. In the folded position, the inner surfaces of the upper and lower parts may substantially face each other.

The mounting bracket 143 is configured to be attached to or to be integrally formed with the bed, such as to the deck or frame of a bed (located below the mattress platform). The external/upper part pivot arms 142 may be configured to directly or indirectly attach to the mounting bracket 143, as would be appreciated by a person skilled in the art.

In one form, the upper part pivot arms 142a, 142b are angled toward the mounting bracket 143. The angle of the pivot arms 142 may be substantially sharp and angular or the angle may be curved, as shown in Figures 2, 3, and 7. Typically, the angle of each pivot arm 142a, 142b is approximately 90° . In other forms, one or both pivot arms may be substantially straight. In effect, the pivot arms may form an angle of anywhere between 0° and about 180°. However, in the preferred form as illustrated, each pivot arm comprises a first leg that attaches to the respective upper or lower part of the side rail and a second leg that attaches to the mounting bracket. The first and second legs preferably join at an angular or curved right angle.

In one form, the lower part pivot arm 141 is angled toward the mounting bracket 143. The angle of the lower part pivot arm may be substantially sharp or the angle may be curved, as shown in Figure 3. The lower part pivot arm 141 may be configured to directly or indirectly attach to the mounting bracket 143 and positioning mechanism mounting block 125, as would be appreciated by a person skilled in the art.

In one form, as illustrated, the fourth hinged/pivot joint 128 of the mounting bracket, which attaches to the lower part pivot arm 141, is located above the third hinged/pivot joint 127 that attaches to the upper part pivot arms, as shown in Figure 3. The mounting bracket may comprise a raised portion on which the fourth pivot joint 128 is located to provide a vertical distance between the third and fourth pivot joints, 127, 128. The vertical distance between the pivot joints 127, 128 provides stability to the upper part 120 during raising, during lowering and when it is either in the up or down position. The location of the third pivot joint below the fourth pivot joint also provides the lower part pivot arm with a shorter reach below the bed compared to the upper part pivot arm when the upper and lower part pivot arms of the same length.

A portion of the lower part pivot arm 141 may be located in front of the front surface of the lower part 130 or behind the lower part 130 of the side rail 100, and/or may be attached or integral with the lower part 130 of the side rail 100. In the embodiment illustrated, an upper portion of the lower part pivot arm 141 is located in front of the front surface of the lower part 130 and is also attached to the lower part 130 of the side rail. In any of these configurations, the lower part pivot arm 141 may be configured to cause the lower part 130 of the side rail to fold towards the upper part 120 of the side rail when the side rail is moved to a lowered position.

In one form, the lower part pivot arm 141 may be configured to nest between and to substantially fill the gap between the upper part pivot arms 142a, 142b. In this configuration, the risk of a person's fingers or other body part being caught in entrapment points between the moving pivot arms is reduced.

The top part 120 of the side rail may comprise a handle 115 and/or a gripping region by which a person can grip the side rail 100 and lower it down to a lowered position or pull it up to a raised position.

In the embodiment illustrated, the body 110 of the side rail 100 and its upper and lower parts 120, 130 are substantially rectangular. The shape of the lower part 130 provides the side rail with a bottom edge 132 that may substantially correspond with the mattress platform of a bed to avoid entrapment points between the side rail 100 and the mattress platform. However, it should be appreciated that the body 110 may be of any suitable shape. For example, the body may be substantially rectangular with curved corners at the top edge of the side rail. In another form, a bottom edge of the upper part may be curved and a top edge of the lower part may be curved to correspond with the bottom edge of the upper part. Although the side rail may take many different shapes without departing from the scope of the invention, it is generally preferred that the body of the side rail is shaped to avoid creating entrapment points between the side rail and the mattress platform of the bed and between the upper and lower parts of the side rail . For example, it is preferred that the bottom edge of the upper part corresponds with the top edge of the lower part and that the upper and lower parts are positioned proximate to each other to minimise the risk of an entrapment point occurring between the two parts.

In one form, as illustrated, the upper and/or lower parts of the side rails are substantially configured as panels, rather than as a framework of bars, to avoid a patient's arm or other body part becoming caught in the side rail.

In use, when the side rail 100 is raised, as shown in Figures 2 to 4, the upper part 120 of the side rail and much of the lower part 130 may project above the mattress platform of the bed.

A person can lower the side rail 100 by pushing the side rail downwardly toward the floor. Optionally, the side rail comprises a lock that locks the side rail in the raised position. In this embodiment, the lock must be released before the side rail can be lowered.

As the side rail 100 is lowered, the pivot arms 141, 142 rotate around the hinged/pivot joints 128 and 127 of the mounting bracket respectively and about hinged/pivot joints 150 and 126 of the side rail or mounting block of the side rail. The angled pivot arms 141, 142 are configured to control the motion of the side rail 100 so that the upper part 120 of the side rail is able to lower without moving significantly towards or away from the bed. In one embodiment, the side rail is configured so that the upper part 120 lies in substantially the same vertical plane when it is in the raised position and when it is in the lowered position. Figures 5 to 8 show the side rail in the lowered position.

The upper part pivot arms 142 allow the upper part 120 of the side rail to move downwardly to a point of maximum movement, while simultaneously, the lower part pivot arm 141 allows the lower part 130 of the side rail to move downwardly to a point of maximum movement. Once the side rail 100 is in the fully lowered position, the inner surface or rear surface 133 of the lower part 130 of the side rail substantially faces toward the inner surface or rear surface 123 of the upper part 120 of the side rail. The inner/rear surfaces of the two parts of the side rail being those surfaces that face toward the bed when the side rail is in a raised position, as shown in Figure 4B. In effect, in the lowered position, the two parts of the side rails are substantially folded together, forming a more compact side rail. In this lowered position, the bottom edge 132 of the lower part 130 is located above the top edge 131 of the lower part 130, as shown in Figure 7.

Although the positioning mechanism has been described as having upper part pivot arms that are located on either side of a lower part positioning arm, in other forms, the positioning mechanism may comprise a pair of lower part pivot arms located between a pair of upper part pivot arms. In yet another form, the positioning mechanism may comprise one or more upper part pivot arms that are located between a pair of lower part pivot arms. In yet another form, the positioning mechanism may comprise a single upper part pivot arm and a single lower part pivot arm. In this configuration, each pivot arm is preferably located substantially centrally along the length of the side rail. Preferably, the centrally located pivot arms lie adjacent to each other in a side by side arrangement. Each configuration of pivot arm connects to the respective upper and lower parts of the side rail and the mounting bracket as described above and operates in the same manner to raise and lower the side rail, as described above.

The side rail 100 may be configured to comprise a locking system comprising a lock that locks the side rail in the raised position. For example, in one form as shown in Figures 9A and 9B, the side rail comprises a locking system 200. The locking system 200 is configured to lock the internal and external pivot arms 141, 142 of the side rail 100 together when the side rail is in a raised position, so that the side rail is unable to be lowered.

The locking system 200 comprises a lock comprising a locking member 210 and a receiving member 220. The locking member 210 is configured to engage with the receiving member 220 when the side rail 100 is locked in a raised position and to disengage with the receiving member to allow the side rail to be unlocked and moved to a lowered position.

In one form, the locking member 210 comprises a locking arm. The receiving member 220 comprises an opening 221, such as an aperture or recess. The locking arm 210 is dimensioned to be received within the opening 221 of the receiving member 220. The receiving member 220 may be rotatably mounted on a pivot member 222 so that the receiving member 220 may rotate or pivot toward the locking arm 210, to allow the locking arm to be received within the opening 221 of the receiving member. When the locking arm 210 is held within the opening 221 of the receiving member, the locking arm 210 is engaged with the receiving member 220 and the locking system 200 is locked, as shown in Figure 9A. The rotating receiving member 220 may also rotate away from the locking arm 210 to disengage the locking arm 210 and receiving member 220 and unlock the locking system 200, as shown in Figure 9B.

The locking member 210 may be attached to the internal/lower part pivot arm 141 or the external/upper part pivot arm 142. Similarly, the receiving member 220 may be attached to the internal/lower part pivot arm 141 or the external/upper part pivot arm 142, but is preferably not attached to the same pivot arm 141, 142 as the locking member 210. For example, in one form, the locking member 210 may be attached to the external pivot arm 142 and the receiving member 220 may be attached to the internal pivot arm 141. In another form, as shown in Figures 9A and 9B, the locking member 210 may be attached to the internal pivot arm 141 and the receiving member 220 may be attached to one or both external pivot arms 142.

The receiving member 220 may be configured to press firmly against the locking arm 210 to help ensure that the receiving member and locking arm are firmly engaged with each other. In one form, the locking system 200 may comprise a compression member 230 that presses against the receiving member 220 to push the receiving member toward the locking arm 210. Preferably, the compression member is a spring, but in other forms, the compression member may be any suitable compressible and resilient material, such as a foam material for example. Optionally, the foam material is formed in a tubular cylinder shape.

In one form, the compression member 230 is held within a housing 231 having an opening at one end. One end of the compression member presses against a closed end of the housing 231 and the other end extends through the opening of the housing 231 to press against the receiving member 220.

In one form, the receiving member comprises a projection configured to project into a central region of the compression member (such as into the centre of the spring if the compression member is a spring, or into the centre of the tube if the compression member is a tubular foam cylinder) to hold the spring in position in relation to the receiving member. The compression member housing also helps to hold the compression member in position.

The locking system 200 may also comprise an actuator 240, which a user may manipulate to cause the locking system to lock or unlock. In one form, the actuator 240 comprises a lever attached to the side rail 100. The lever 240 may be connected to the receiving member 220 and may be configured to rotate about the same pivot member 222 as the receiving member. In this configuration, as the lever 240 is caused to rotate about the pivot member 222, the receiving member 220 is also caused to rotate about the pivot member 222. For example, rotating the lever 240 in a first direction may cause the receiving member 220 to rotate toward and engage with the locking member 210, as shown in Figure 9A, whereas rotating the lever 240 in a second direction may cause the receiving member

220 to rotate away from and disengage with the locking member 210, as shown in Figure 9B.

Preferably, one end of the lever 240 is attached to or integral with the receiving member 220. In one form, the lever 240 and receiving member 220 form a substantially L- shaped arrangement.

In one form, the lever 240 comprises an arm 241 that comprises a slot 242 configured to receive a guide pin 250 so that the guide pin 250 can slide within the slot 242 as the lever 240 is pivoted between the locked and unlocked positions. The guide pin 250 may be used to control and limit the range of movement of the lever 240.

When the locking system 200 is locked, the locking arm 210 is held within the opening

221 of the receiving member 220 and locks the internal 141 and external 142 pivot arms in the raised position. Because the pivot arms 141, 142 form a four bar link-type arrangement, the pivot arms 141, 142 are unable to lower until the locking system 200 is unlocked. Once the locking arm 210 is retracted from the receiving member 220, the pivot arms 141, 142 are able to move freely and will begin to drop to the lowered position under the weight of the side rail 100. In one form, the side rail 100 is configured so that in its lowered position, the top edge 121 of the upper part 120 is substantially level with, below, or slightly above the mattress platform of the bed. The side rail 100 is also configured so that in the lowered position, the side rail is sufficiently compact to enable the mattress platform to be low while maintaining clearance with the floor. Therefore, the side rail of the invention is a compact, foldable side rail that provides a care bed with a significant range of movement without compromising safety or comfort and ease of egress for the occupant/patient.

In one form, the side rail is attached to the deck so that the side rail does not tilt when the mattress platform is adjusted/tilted, such as when the back rest is raised to 45° from horizontal. For example, by attaching the side rail to the deck rather than the mattress platform, the side rail will remain substantially horizontal with the deck as the position/orientation of the mattress platform is adjusted . In this configuration, entrapment points between the side rail and adjacent immovable components (relative to the siderail) are avoided or minimised . However, in another form, the side rail may be attached to the mattress platform so that the side rail moves with that portion of the mattress platform to which it is attached.

In one form, the side rail may be configured to comprise one or more sensors 300 for sensing whether the side rail is in a raised or lowered position . The sensor(s) 300 may be configured to generate an electric signal that is received by a control system 400 for the side rail and/or the bed to which the side rail is attached. The control system 400 may be configured to limit and control the low height of the bed relative to the floor based on the signals received from the sensor(s).

The control system may comprise a processor that processes the signal to identify the position of the side rail. Where the side rail is in a raised position, the control system may identify the side rail as being in a raised state. Conversely, where the side rail is in a lowered position, the control system may identify the side rail as being in a lowered state. Optionally, the control system may be configured to identify when the side rail is between states as the side rail is moving from one position to another. Alternatively, the control system may simply continue to identify the side rail as being in the most recently identified state/position until a positive signal is received to indicate that the side rail is now in the other state/position.

The control system 400 may be positioned at any suitable location on the side rai l or bed, such as on the upper or lower part of the side rail or on the bed deck or bed frame. In one form, the control system 400 may be located on the upper part of the side rail . Optionally, the control system 400 forms part of a bed control system that is configured to cause the bed to raise or lower or tilt and/or to cause the mattress platform portions of the bed to tilt. In a preferred form, the control system is located on the bed deck. However, it is envisaged that the control system could be positioned at any suitable location on the bed, such as on the frame. Figures 10A and 10B illustrate just some possible positions of sensors 300 that may be attached to or integrally formed with the side rail. Any suitable sensors may be used to sense the position of the side rail at any suitable location on the side rail and/or bed .

In one form, a sensor 300 may comprise two or more sensor components that are located at different locations on the side rail and/or bed and that together act to form a sensor. For example, a sensor may comprise two components comprising a Reed switch 300a and a magnetic trigger 300b. The magnetic trigger may be any component that produces a magnetic field to trigger the Reed switch, such as a typical magnet or a magnetic field inducing coil for example. The Reed switch and magnetic trigger form sensor components that may each be located on any suitable surfaces of the side rail and/or bed to indicate whether the side rail is in a raised or lowered position. In one form, a Reed switch and magnetic trigger combination may be located on surfaces of the internal and external pivot arms 141, 142 that face toward each other. For example, a Reed switch 300a may be located on an outer side surface of the internal pivot arm 141 and a magnetic trigger 300b may be located on an inner side surface of the external pivot arm 142 to face the Reed switch. In another form, the positions of the Reed switch and magnetic trigger may be reversed. The Reed switch and magnetic trigger may be located on the respective pivot arms so that the Reed switch is activated by the magnetic trigger to produce a signal when the side rail is raised or when it is lowered. This can be achieved by positioning the two components on the pivot arms at locations where the two components are close together when the side rail is in the raised position or when the side rail is in the lowered position .

Each time the sensor is activated, it produces a signal that is received by the control system. In one form, the control system may be configured to toggle the state of the side rail between a raised state and a lowered state each time that a sensor signal is received. In another form, one or more sensors may be used to identify when the side rail is in a raised position and one or more other sensors may be used to identify when the side rail is in a lowered position. The control system may be configured to identify which sensor(s) are associated with each position of the side rail, so that when a signal is received from the sensor(s) associated with the side rail being raised, the control system identifies that the side rail is in the raised state. Conversely, when a signal is received from the sensor(s) associated with the side rail being lowered, the control system identifies that the side rail is in the lowered state.

In another form, the two components on the pivot arms may be positioned at locations that allow the two components to come close together when the side rail is moving between positions. In this embodiment, the Reed switch and magnetic trigger may be located so that each time the side rail is raised or lowered, the Reed switch is activated as the magnetic trigger comes close to and then moves away from the Reed switch. In this embodiment, the control system is programmed to toggle the sensed states of the side rail between a raised state and a lowered state with each sensor signal. Under this arrangement, it is necessary to initially program the control system with the correct state/position of the side rail and from that point in time, the toggled positions of the side rail should remain correct.

As will be appreciated, the one or more sensors may be positioned on any part of the side rail and/or bed that moves toward and away from any other part. For example, one or more sensors may be located on an internal pivot arm 141 (300a, 300c); an external pivot arm 142 (300b, 300d); the upper part 120 of the side rail (300h); the lower part 130 of the side rail (300f, 300g); at or near the hinged joint 150 between the upper and lower parts 120, 130 of the side rail (300e); and/or on the bed (300i) .

In another form, where at least one sensor comprises a pair of sensor components, at least one sensor component 300c may be located on the external pivot arm 142 and a corresponding sensor component 300d may be located on the lower part 130 of the side rail . In another form, corresponding sensor components 300f, 300g may be located on the upper and lower parts 120, 130 of the side rail. In another form, corresponding sensor components may be located at or near the hinged joint 150 between the upper and lower parts 120, 130 of the side rail. In yet another form, corresponding sensor components may be located on the side rail and on the bed for example. Any one or more of these sensor arrangements may be used alone or in combination with any other sensor arrangement as would be apparent to a person skilled in the art.

Any suitable type of sensor(s) may be used within the side rail and/or bed to sense the position of the side rail. For example, one or more proximity sensors; near field sensors; or capacitive sensors may be used. In one form, one or more touch sensors may be used. In one form, touch sensor(s) may be activated by a mechanical switch, such as a mechanical lever. Optionally, the mechanical lever comprises a small roller lever 300e following a cam. The lever is configured to rotate as the side rail is raised and lowered and to contact a touch sensor 300f to generate an electronic signal to be received by the control system.

In one form, the control system may comprise a microprocessor configured to receive signals from the sensor(s) and to produce actuating signals to cause components of the bed to adjust the height of the bed in response to a user input. The control system may be configured to move the bed to a particular height based at least in part on the user input and in part on the position of the side rail. For example, if the control system identifies that the side rail is in the raised position and a user inputs an instruction to lower the bed, such as via an input on a control panel for the bed, the control system may be configured to cause the bed to lower to a minimum height. Alternatively, if the control system identifies that the side rail is in a lowered position and a user inputs an instruction to lower the bed, the control system may be configured to prevent the bed from lowering until the side rail is raised. In another form, the control system may be configured to allow the bed to be lowered when the side rail is in the lowered position, but only to a low height at which sufficient clearance is provided between the floor and the lower part of the side rail. Preferably, this low height is at or above 8cm from the floor. For example, the control system may be configured to lower the bed to a low height when the side rail is lowered and to a minimum height when the side rail is raised. The minimum height is lower (closer to the floor) than the low height. The minimum height may be as low as 2cm for example.

By using sensors to indicate the position of the side rail and/or bed, it is possible for the bed to be lowered safely to a minimum height without risking harm to a person's foot or other object that may be located between the side rail and the floor.

The side rail of the invention is configured so that its top edge can be lowered to be substantially level with, below, or slightly above the mattress platform of a bed and to provide sufficient foot clearance between the side rail and floor when the bed is lowered to its lowest position. By lowering the side rail so that the top edge of the side rail (i.e. the top edge of the upper part of the side rail) is substantially the same height as the mattress platform, or to a position where the top edge is below the mattress platform, it is more comfortable and easier for a patient to get off a bed bearing the side rail because the side rail is less likely to dig into the patient's thigh as he or she gets out of bed. This is particularly the case when the entire side rail is beneath the mattress when the side rail is in the lowered position. The ability of a person to easily and comfortably exit the bed with the side rail in place is also provided for by the nature of the positioning mechanism, which allows the side rail to remain close to the side of the bed when the side rail is in its lowered position.

Another advantage provided by the side rail of the invention is that it avoids entrapment points where possible. For example, the upper and lower parts of the side rail are placed close together to avoid the risk that a person could trap a finger or other part of the body between these two parts. The lower part of the side rail is also configured to be positioned close to the side of the bed when in a raised position to reduce the risk that a person's arm or other body part may be trapped between the side rail and bed. When the side rail is at least partially or fully below the mattress of the bed, it is much easier for the bed to be made without trapping a person's hand between the side rail and the mattress.

Yet another advantage is provided where the length of the lower part is substantially equal to the length of the upper part and the bottom edge of the lower part is shaped to substantially match the edge of the bed and to be positioned near the edge of the bed to avoid entrapment points between the bed and side rail.

Yet another advantage may be provided where the internal pivot arm nests between the external pivot arms and substantially fills the gap between the external pivot arms to minimise entrapment points between these moving parts.

Although the invention has been described by way of example, it should be appreciated that variations and modifications may be made without departing from the scope of the invention as defined in the claims. Furthermore, where known equivalents exist to specific features, such equivalents are incorporated as if specifically referred in this specification.

For example, in another form, the internal and external pivot arms may be substantially straight.

Claims

What we claim is:

1. A two-part side rail for a bed, the side rail being configured to move between a raised position and a lowered position, wherein the side rail comprises:

a body comprising an upper part and a lower part that is hinged from the upper part at a first pivot joint; and

a positioning mechanism comprising :

an upper part pivot arm comprising a first end that attaches to the upper part via a second pivot joint, and a second end that attaches to the bed via a third pivot joint; and

a lower part pivot arm comprising a first end that is fixedly attached to the lower part, and a second end that attaches to the bed via a fourth pivot joint, wherein lowering the side rail causes the upper part pivot arms to pivot downwardly to allow the upper part of the side rail to move downwardly to a point of maximum movement, while simultaneously, the lower part pivot arm pivots downwardly to allow the lower part of the side rail to move downwardly to a point of maximum movement and to cause the lower part to fold towards the upper part.

2. The side rail of claim 1, wherein the upper and lower parts are of substantially the same length and the lower part comprises a top edge configured to substantially correspond to a bottom edge of the upper part.

3. The side rail of claim 1 or 2, wherein the lower part is substantially in the form of a panel.

4. The side rail of any one of the preceding claims, wherein the positioning mechanism comprises an internal pivot arm forming the lower part pivot arm and a pair of external arms forming upper part pivot arms, wherein the lower part pivot arm is located between the upper part pivot arms, wherein the second ends of the upper and lower part pivot arms are attached to the bed via a mounting bracket and wherein the third and fourth pivot joints are located on the mounting bracket.

5. The side rail of claim 4, wherein the third pivot joint is located on the mounting bracket below the fourth pivot joint.

6. The side rail of claim 4 or 5, wherein the internal arm is configured to nest within the external arms.

7. The side rail of any one of claims 4 to 6, wherein the lower part and upper part pivot arms are angled toward the mounting bracket.

8. The side rail of claim 7, wherein the lower part and upper part pivot arms are curved toward the mounting bracket.

9. The side rail of any one of claims 4 to 8, wherein the lower part pivot arm is configured to substantially fill a gap between the upper part pivot arms that are spaced apart from each other.

10. The side rail of any one of claims 4 to 9, wherein the positioning mechanism is attached to the side rail at an area that is substantially central along the length of the side rail.

11. The side rail of any one of the preceding claims, wherein the side rail further comprises a locking system configured to lock the pivot arms when the side rail is in a raised position and to unlock the pivot arms to allow the side rail to be lowered to a lowered position, wherein the locking system comprises a locking member located on the lower part pivot arm and a receiving member that is attached to at least one of the upper part pivot arms at a pivot member and that is configured to engage with the locking member to lock the side rail in a raised position and to disengage from the locking member to unlock the side rail.

12. The side rail of claim 11, wherein the receiving member comprises a pivoting latch and the locking member comprises a locking arm configured to be received within a recess or opening of the latch .

13. The side rail of claim 11 or 12, wherein the locking system comprises a compression member configured to press the receiving member against the locking member.

14. The side rail of any one of claims 11 to 13, wherein the side rail further comprises an actuator connected to the receiving member and arranged to pivot the receiving member toward and away from the locking member to engage and disengage the locking member and receiving member respectively.

15. The side rail of any one of the preceding claims, wherein the side rail comprises one or more sensors configured to generate an electric signal when the side rail moves between a raised position and a lowered position and a control system to receive signals from the one or more sensors to identify whether the side rail is in a raised position or a lowered position and to control the minimum height to which a bed bearing the side rail can be lowered depending on the identified position of the side rail.

16. A bed comprising a frame supporting a bed deck supporting a mattress platform, wherein the bed comprises at least one side rail of any one of claims 1 to 15.

17. The bed of claim 16, wherein the side rail is attached to the bed deck.