GB2143726A - Patient supporting appliances - Google Patents

Abstract

An appliance for supporting a patient in a prone position having a platform carried by a supporting structure and including a headrest portion at one end of the platform tiltable about a transverse horizontal axis, and wherein the angular position of the headrest portion is controlled by a position controlling mechanism comprising a locking member (11) rockable about an axis (12) and having an aperture (16) through which a locking bar (10) connected to the headrest portion passes to provide for locking or binding of the bar in the aperture (16) in a locking position of the locking member (11) or free movement in a releasing position of the locking member. The locking member is normally prevented from movement into its releasing position by downward loading of the locking bar (10) producing and clockwise biasing of the locking member, and additionally by a setting means comprising a stop member (20) pivotable about the axis (12) by a handle (21). The operator must both raise the handle (21) and relieve the weight exerted by the headrest portion on the bar (10) before the locking member (11) can move anti-clockwise into its releasing position. <IMAGE>

Description

SPECIFICATION Improvements relating to couches or like patient supporting appliances.

This invention relates to patient supporting applicances (hereinafter referred to as being of the kind specified) each in the form of a bed, couch, table or the like having a generally upwardly presented horizontal, or approximately horizontal, platform of dimensions such that the patient can lie full length thereon, supporting structure for supporting the platform, and the platform including at one end at least an upwardly tiltable portion (herein called the headrest portion) for supporting the patient's head and possibly shoulders or some other part of the patient's body, and position controlling mechanism for holding the headrest portion in different angular positions relatively to the remainder of the platform.

One of the problems which is encountered in using appliances of the kind specified is that it is highly desirable that ability to move the headrest portion into different angularly adjusted positions shall be capable of being effected simply and quickly and that it should be reliably held in such position, but that, when once set in a given position, it shall not be capable of being disturbed inadvertently which may be particularly serious where the patient is undergoing medical attention.

An object of the present invention is to provide a new or improved appliance of the kind specified wherein this requirement is more nearly attained than has been the case hitherto.

According to the present invention there is provided an appliance of the kind specified wherein the position controlling mechanism for the headrest portion comprises components operatively connected respectively to the main portion of the platform or supporting structure therefor and to the tiltable headrest portion in a manner such as to undergo relative movement during positional adjustment of the headrest portion, these components being settable into a locking position or condition in which they prevent such relative movement and hold the headest portion in an adjusted position, or a releasing position in which they permit of said relative movement and allow positional adjustment of the headrest portion to take place, and wherein setting means are provided for establishing the position controlling mechanism in its locking or releasing position or condition, the arrangement being such that the combination of positions controlling mechanism and setting means entails two distinct operations being performed before the position controlling mechanism is established in its releasing position or condition.

In a preferred arrangement one of the components of the position controlling mechanism comprises a locking bar and the other of the components comprises a locking member having an aperture through which the bar extends and through which it is movable longitudinally relatively to the locking member during positional adjustment of the headrest portion, the locking member being mounted for movement in another mode relatively to the bar between locking and releasing positions in the former of which it binds or locks to prevent said longitudinal movement of the bar, and in the latter of which it permits of such longitudinal movement, and wherein the setting means comprises a stop member movable manually between an operative position, in which it prevents movement of the locking member into its releasing position, and an inoperative position in which it permits of such movement.

The invention will now be described by way of example with reference to the accompanying drawings wherein; Figure 1 is a plan view of one embodiment of examination couch incorporating the invention; Figure 2 is a view in side elevation of the couch of Figure 1; Figure 3 is a fragmentary view on an enlarged scale showing the position controlling mechanism for the headrest portion in side elevation; and Figure 4 is a fragmentary diagrammatic view on a still further enlarged scale of the position controlling mechanism.

The appliance may comprise an examination couch having a platform 1 which is is carried by a supporting structure including a frame 2 preferably mounted on legs 3 which may be provided with castor wheels (not shown) for convenient movement from place to place. The platform portion inciudes a mqin portion 4 which is horizontal, or approximately so, and which is connected or associated at one end with a headrest portion 5. This is supported by a sub-frame having side members 6 pivoted about a transverse horizontal axis 7 to the frame 2, and connected by a cross member 8, so that the headrest portion 5 can tilt about the horizontal axis 7 to provide underlying support to the patient's head or possibly head and shoulders.

For retaining the headrest portion in any of a number of adjusted positions, a position controlling mechanism is provided, one component of which comprises a locking bar 10 which at its upper end may be pivotally connected about a horizontal axis to a bracket 9 or other suitable part of the subframe supporting the headrest portion. A further component of the position controlling mechanism comprises a locking member 11 in the form of a plate which is pivotally mounted on the supporting structure of the appliance for rocking movement about horizontal axis 12, for this purpose the locking member including a pair of laterally spaced upstanding ears or lugs 13 apertured to receive a pivot pin 14.

The locking member 11 has a centre of gravity which is to the left of a vertical plane 15 passing through the axis 14 and hence it is gravitationally biased to rotate anti-clockwise from the position shown which represents the locking position. The bar 10 passes through an aperture 16 in the locking member. This aperture may include countersunk portions 16a, 1 6b at each end and a mid portion 16c which is cylindrical, and preferably presents (in cross-section) an obtuse angle where it joins with the countersunk portions.The locking bar 10 may be of circular form in transverse cross-section and tends to make contact with the locking member when in its locking position at the corners or angles formed at the junction of the countersunk portion 16a and cylindrical portion 16e at the left-hand side as seen in the Figure, and similarly at the corner formed by the countersunk portion 1 6b and the cylindrical portion 1 6c at the right-hand side.

Assuming that the load transmitted to the locking bar 10 from the headrest portion is in a downward direction, as indicated by arrow 17, the force transmitted to the locking member tends to rotate this clockwise and therefore establish even greater contact pressure between the corners referred to and the locking bar 10 so that the locking bar 10 is subject to a binding or locking action preventing it moving downwardly through the aperture 16.

To allow the locking member 11 to move into its releasing position in which the axis of the aperture 16 would be parallel, or more nearly parallel, to the axis of the locking bar 10, it is thus necessary for the downward load on the bar 10 to be relieved and that the operator should, therefore, slightly lift or at least take the weight downwardly from the headrest portion.

Additionally there is provided a setting means comprising a stop member 18 which may be in the form of a stirrup, or crank, having an arm, or arms (19), and pivotally mounted for angular movement about the axis 12 and having a pin portion 20 extending laterally and which bears on the upper surface of the locking member 11 at a position where it does not form an obstruction to the passage of the locking bar 10 through the aperture.

The arms 19 (or a single arm if such is utilised) may be rigidly connected to the spindle 14 to which is also fixed an operating handle 21. The weight of the latter tends to turn the spindle 12 and hence the locking member clockwise and serves strongly to bias the locking member 11 towards its locking position, thereby overcoming any weight bias due to the locking member 11 itself, urging the locking member in the opposite direction towards its releasing position.

In order to effect positional adjustment it is therefore necessary for the operator to lift the handle 21 and bring the pin 20 of the stop member out of contact with the locking member 11 so as to the gravitational bias of this member alone to move it into its releasing position. As previously mentioned, however, this can be attained only if the locking bar 10 is relieved of downward load.

Therefore, it is necessary fir the operatorto carry out two distinct operations, namely to lift the handle 21 and lift or take the weight of the headrest portion before the angular position of the latter can be adilXsted.

This arrangement, therefore, provides a simple and reliable means for ensuring that the headrest portion cannot be inadvertently displaced from its set position, for example by inadvertent contact with the handle 21 alone. At the same time, adjustment can be carried out accurately simply and quickly.

It will, of course, be understood that although for convenience the headrest portion has been referred to as supporting the head or possibly the head and shoulders of a patient, the invention may be applied to appliances wherein the "headrest portion" is of larger size and supports part of the torso of a patient as well.

Further, it will be understood that instead of relying on gravitational biasing means for the locking member 11 and the stop member 20 and its handle, spring means could be used in substitution orto supplement the gravitational biasing.

Further, if desired, instead of relying upon frictional locking or binding of the bar 10 in the aperture 16, the bar could be notched or serrated to provide positive locking.

Claims (7)

1. An appliance of the kind specified wherein the position controlling mechanism for the headrest portion comprises components operatively connected respectively to the main portion of the platform or supporting structure therefor and to the tiltable headrest portion in a manner such as to undergo relative movement during positional adjustment of the headrest portion, these components being settable into a locking position or condition in which they prevent such relative movement and hold the headrest portion in an adjusted position, or a releasing position in which they permit of said relative movement and allow positional adjustment of the headrest portion to take place, and wherein setting means are provided for establishing the position controlling mechanism in its locking or releasing position or condition, the arrangement being such that the combination of position controlling mechanism and setting means entails two distinct operations being performed before the position controlling mechanism is established in its releasing position or condition.

2. An appliance according to claim 1 wherein one of the components of the position controlling mechanism comprises a locking bar and the other of the components comprises a locking member having an aperture through which the bar extends and through which it is movable longitudinally relatively to the locking member during positional adjustment of the headrest portion, the locking member being mounted for movement in another mode relatively to the bar between locking and releasing positions in the former of which it binds or locks to prevent said longitudinal movement of the bar, and in the latter of which it permits of such longitudinal movement, and wherein the setting means comprises a stop member movable manually between an operative position in which it prevents movement of the locking member into its releasing position and an inoperative position in which it permits of such movement.

3. An appliance according to claim 2 wherein the locking member is biased towards its releasing position but is prevented from moving into said position both by the stop member of the setting means when the latter is in its operative position and by load transmitted to the position controlling mechanism from the tiltable head portion.

4. An appliance according to claim 3 wherein the locking member is mounted for rocking movement between its locking and releasing positions and is biased gravitationally towards the latter, and where in engagement between the locking bar and the boundary of the aperture through which it passes urges the locking member towards its locking position.

5. An appliance according to claim 4wherein the stop member is mounted for angular movement about the rocking axis of the locking member and is movable from its operative position, towards which it is urged by further biasing means, to its releasing position by a manually operable handle.

6. Any novel feature or combination herein described and/or shown in the accompanying drawings.

7. An appliance of the kind specified having a position controlling mechanism and setting means for the headrest portion substantially as hereinbefore described with reference to and as shown in the accompanying drawings.