EP0705091B1

EP0705091B1 - Intensive therapy bed

Info

Publication number: EP0705091B1
Application number: EP94912020A
Authority: EP
Inventors: Stephen 46 Wallows Wood The Straits Hayes
Original assignee: J Nesbit Evans and Co Ltd
Current assignee: Huntleigh Technology Ltd
Priority date: 1993-05-22
Filing date: 1994-04-06
Publication date: 1997-05-02
Anticipated expiration: 2014-04-06
Also published as: ATE152343T1; GB9310572D0; DE69402978D1; AU6434094A; DE69402978T2; GB9406679D0; WO1994027547A1; EP0705091A1; GB2278264A

Abstract

An intensive therapy bed comprises a mattress support (16) which is longitudinally slidable on a perimeter frame (12), and all of the mechanism 40 - 48 for causing the sliding and also for profiling the mattress frame as shown in Figure 1 is provided along one edge of the mattress frame. Height adjustment and also tilting and rocking is effected by jacks 57, (70) provided in pillars 62, 64 at opposite ends of a chassis, and the chassis itself includes a longitudinal member 50 which is offset to the same side of the bed as the actuator motors. This leaves a relatively large unobstructed area which is X-ray transparent. <IMAGE>

Description

This invention relates to hospital beds especially for intensive therapy.
It is known to provide beds designed to be raised and lowered, tilted longitudinally (Trendelenburg movements) and laterally, and also profiled. It is also known to provide beds with central areas which are X-ray transparent so as to facilitate imaging and other treatments or diagnostic techniques. Some of these many features have been combined together, but in the past so far as is known to applicants, the provision of most or all of these features has proved to be impossible because many of them appear to be mutually incompatible. Hence, the extent of the variable height facility has been limited, or the capability of tilt to a required maximum has not been possible in all height positions and so on. Consequently it has been common to accept the need to transfer a patient from for example a geometrically versatile but X-ray opaque design to a simpler and non-versatile trolley for transfer, and then to a table which is largely X-ray transparent, and back again after X-ray diagnosis has been performed. This creates difficulties with particularly ill patients. There is therefore a need for a more versatile bed capable of use in or for all of these purposes and positions so as to avoid the need for transfer.
USP 3818516 discloses a hospital bed including a mobile base frame provided with two pairs of power actuated links for raising and lowering an intermediate support frame. An upper bed section is carried on the support frame and is slidable lengthwise of it. An articulated mattress frame is mounted on the carriage frame. The mattress frame can be profiled to support a patient sitting up in bed. The arrangement allows the mattress frame to be both adjusted in height and tilted foot down or head down, and also the mattress frame to be slid so as to project beyond the intermediate support frame to allow X-ray imaging in an area free from the links and power actuated means for controlling the various movements.
French Patent 7919821 discloses a bed having a mobile base frame, an intermediate support frame and a profiling mattress support located thereon, with a single telescopic ram at each end for raising and lowering the intermediate frame without any possibility of tilting, and in which there is an internal recess extending longitudinally between the rams and substantially across the width of the bed which allows accessibility of the bed for radioscopy. The mechanism for causing the raising and lowering and also for controlling the profiling of the mattress support are arranged outside the imaging area.
According to the invention an intensive therapy bed comprises a first peripheral frame surrounding an imaging window, said frame being slidably connected to an outer frame and with a first actuator motor located laterally of said frame and outside said window for causing said sliding, said outer frame hingedly mounting one or more panel-like mattress supports and carrying along one lateral edge and outside said window one or more further actuator motors for displacing one or more of the panel-like supports to inclined positions at least as a backrest and possibly also to provide a so-called knee-break for complete profiling, and the first frame being mounted upon a pair of height adjustable pillars connected to yet further actuator motors also located laterally of the bed and outside said window whereby the frames may be raised or lowered and tilted or levelled by operation of one or other of said further actuators in the same or opposite directions.
The X-ray imaging area is wholly within the first frame. All of the mattress profiling equipment may also be located within the first frame but entirely at one side thereof in a relatively narrow zone so that the said area is substantially wider than the area required in any normal position of a patient for X-ray.
The pillars are to be located at the ends of the frame and as near to the respective ends of the bed as possible thus enabling an area substantially equal to the length of the frame and patient to be X-rayed. However, if the patient's feet or head extend beyond the ends of the first frame, since the mattress frame is or may be longer, sliding movement of the outer (mattress) frame on the first frame may carry the head or feet within the area of the first frame.
Preferably all of the actuators are controllable from a pair of hand sets, one of which is for patient use and the other for medical staff use. The patient's set may be arranged so that individual controls are operable by the patient but only after release from the staff hand set, so that if a patient requires for example a reverse Trendelenburg position, the patient's hand set is inoperative to alter tilt, and so on. Alternatively or additionally certain controls may be omitted from the patient's set so that the patient may only control the height of the mattress from the floor, the backrest angle and the knee-break (which is further profiling of the mattress so that the supports for the patient's legs make a shallow inverted Vee with the apex under the patient's knees. Desirably the angle between a portion supporting the thighs of the patient and the backrest is controlled to be at least 75^o and any increase in backrest angle which would tend to reduce this also automatically lowers the knee-break.
One embodiment of the invention is now more particularly described with reference to the accompanying drawings in which:-

Figure 1 is a side elevation of a bed showing the mattress frame thereof in a profiled position, and with the bed level;
Figure 2 is a view similar to Figure 1 showing the bed in a tilted position;
Figure 3 is an end elevation showing the bed in a rocked position;
Figure 4 is a view similar to Figure 1 but without profiling, showing the bed level but slid to an extended position for imaging;
Figure 5 is a plan view with the mattress parts in a non-profiled but level position and showing the imaging area,
Figure 6 is a perspective view showing non-profiling, the mattress frame level but rocked; and
Figure 7 is a view with the mattress frame profiled tilted, but not rocked.

Referring now to the drawings, the bed shown therein comprises a first peripheral frame composed of longitudinal members 12 and transverse members 10, and this frame is only slightly smaller than the total mattress area of the bed. Indeed it may be of the same width, but slightly shorter. The area within the frame 10 12, or a substantial part of such area, provides an imaging window which is interconnected by the hatched broken line area 14 in Figure 5.
The said frame 10 12 supports an outer frame 16 18 which is slightly larger, as mentioned, and the outer frame is slidable in the direction of its length for a limited extent (Fig.4). Rollers 19 carried by the outer frame maintain the parts in the sliding relationship and prevent movement of the two parts relative to one another except in that longitudinal sliding relationship. Figure 4 shows the outer frame slid to a maximum extent in one direction relative to the imaging area: Figure 1 shows the frame in mid or normal position. The imaging area does not slide; hence sliding takes different areas into the imaging area.
The outer frame or mattress frame is provided with a series of panels 20 22 24 26 as mattress supports, arranged to be profiled for example as shown in Figs 1,2,6. One panel 20, which forms a backrest, is framed along its longitudinal sides and at the head end of the bed, that is parallel to the members 12 16 and the adjacent member 18 by a U-shaped frame part, and the free ends of the limbs of the U are hinged coaxially on trunnion pins carried by the longitudinal outer frame member 16. The backrest panel is not framed along its edge which contains the hinge axis. Similarly the leg rest panel part 26 is framed on three sides including the edge adjacent the foot of the bed, but not transversely along its hinge axis relative to the thigh rest 24. Panel 22 is fixed relative to the outer frame 16. Thigh rest 24 has parallel framing members edging the longitudinal outer mattress frame part 16 but is not framed transversely of the mattress frame, and is hinged on trunnion pins adjacent the fixed part panel at one end, and on hinge pins to the side framing members of the legrest panel 26 at its other end. So the series of panels is X-ray (etc) transparent over the imaging area 14.
The panels may be folded flat and coplanar as in Figures 3-5, extending substantially between the head and foot end of the bed and from side to side of the bed. The head end 30 and foot end 30 comprise boards carried by vertically extending frame members in conventional manner.
Sliding and profiling is caused by appropriate use of different ones of a series of actuator motors which are located below the frames. A first actuator 40 is fixed to the first peripheral frame and has an output shaft or ram which is displaceable lengthwise of the bed and this is coupled to lug 11 on the outer or mattress frame so as to cause and control sliding of the mattress frame on the first frame.
A second actuator 42 is fixed to the outer frame and its ram is connected via a crank 44 to the backrest so as to lift and lower the backrest.
A third actuator 46 is also fixed to the outer frame and has its ram connected via a crank 48 to lift and lower the thighrest. This latter movement will result in the foot end edge of the legrest moving along the mattress frame. A releasable stay is provided enabling the legrest to be lifted and latched in an for example horizontal position as shown in Figures 1 & 2.
All of the actuators may be low voltage motors with recirculating ball and nut-type drives for the rams. They may be alternatively mains or battery operated. Control may be via one or more handsets 47 shown in a storage portion in Fig 6, with appropriate electronics for safety, to prevent misuse or over-use, and for emergency use. The electronics may be interlinked and controlled by use of memory circuitry, so as to limit the relative angle between one part and another for example between the backrest and the legrest, and to provide minimum angles for one when a certain angle is exceeded for the other, and so on, all as known in the art.
All three actuators and their rams, cranks and other connections and supports are located adjacent one side of the bed, that is in the area not used for the imaging area 14.
The bed is supported on a chassis comprising one laterally disposed (offset) longitudinal member 50 which is below the actuators, and well outside the imaging area (see Fig. 6) and two transverse end members 52 provided with castors 54 and brakes in conventional manner, which are likewise at opposite ends of and outside the imaging area. Each of the members 52 provides a pivotal mounting for a crank 56 connected to a corresponding actuator 57 mounted on the longitudinal member 50, and the cranks are pivoted to a pair of pillars 62 64 connected to the first peripheral frame via pivots having coaxial longitudinal axes and spaced separate transverse axes. The connections are effectively universal joints capable of limited angular movement of the parts.
Simultaneous use of the actuators 57 in the same direction raises or lowers the bed at a fixed angle which may be horizontal, and use of the actuators selectively or in opposite directions changes the level position or angle of tilt to a foot down or head down position or from such positions as the case may be, and all of this may be under the same electronic and memory control.
If the bed is at maximum height, then any desired tilt is achieved by automatic selection of the oppropriate one of the actuators 57. The same is true when at minimum height. Otherwise both actuators are employed acting in opposite directions.
Fig 2, inter alia,, illustrates how tilting to a maximum angle is simplified by placing the pillars near the ends of the chassis, without risk of the mattress frame fouling on the undercarriage parts.
Rocking, that is to say pivoting about the longitudinal axis e.g. to the Figures 3, or 6 position is controlled by a sixth actuator 70 mounted on one bracket 56, and with its ram likewise pivotally coupled to the first frame on a second and parallel longitudinal axis. At the other end of the bed a gas strut 80 extends between the second bracket 56 and the said first peripheral frame generally parallel to the jack 64, and with pivots at each end as a damper. Actuation of the further jack 70 may he continuous or intermittent so as to provide a reciprocating movement for example for pressure relief, or to provide a preset fixed position for example for drainage, and this also may be operated from handset controls as with profiling, height adjustment and longitudinal tilt, and the arrangement is such that rocking can only be effected in the horizontal position.
It is to be noted that the actuators 62 64 70 and strut 80, like the swinging arms 56 are all outside the area 14.
Control links 90 pivoted at their ends on the chassis member 52 and on the bracket 56 maintain the pillars in a near vertical position.

Claims

An intensive therapy bed comprising a first peripheral frame (10,12) surrounding an imaging window (14), said frame being slidably connected to an outer frame (16,18) and with a first actuator motor (40) located laterally of said frames and outside said window for causing said sliding, said outer frame hingedly mounting one or more panel-like mattress supports (20, 22, 24, 26) and carrying along one lateral edge and outside said window one or more further actuator motors (42,46) for displacing one or more of the panel-like supports to inclined positions at least as a backrest and possibly also to provide a so-called knee-break for complete profiling, and the first frame being mounted upon a pair of height adjustable pillars (62,64) connected to yet further actuator motors (57,57) also located laterally of the bed and outside said window whereby the frames may be raised or lowered and tilted or levelled by operation of one or other of said further actuators in the same or opposite directions, and wherein said first frame (10,12) is pivotally mounted on said pillars (62,64) for lateral tilt, and another actuator motor (70) extends generally parallel to one of the pillars between a connection at one end to the first frame and at the other end to a wheeled chassis (50,56) carrying the pillars, at one end of the bed and outside the said window.
A bed as claimed in Claim 1 wherein the wheeled chassis comprises a longitudinally extending member (50) which is lateral of the bed and is located outside said window, and which is unitary with the pair of transversely extending parts (56) which are located at the ends of the chassis and outside said window.