AU2007231665A1 - Bed assembly - Google Patents

Description

1 P/00/011 Regulation 3.2 AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT Name of Applicant: NIAGARA AUSTRALIA PTY LTD Address for Service: INTELLEPRO Patent & Trade Mark Attorneys Level 7 102 Adelaide Street BRISBANE, QLD, 4000 (GPO Box 1339, BRISBANE, 4001) Invention Title: BED ASSEMBLY The following statement is a full description of this invention, including the best method of performing it known to me: 2 BED ASSEMBLY FIELD OF THE INVENTION THIS INVENTION relates to a bed assembly and in particular to a bed assembly adapted to have at least part of the bed assembly move from a flat 5 position into a tilted position. OUTLINE OF THE INVENTION In one aspect the present invention resides in a bed assembly comprising a frame, an articulated foot portion and adjacent thigh portion, the thigh portion and foot portion being moveable relative to one another, the foot portion being 10 moveable firstly and marginally in an axial direction priorto the foot portion being raised. In another aspect there is a bed assembly having an articulated foot portion and adjacent thigh portion, the thigh portion and foot portion being moveable relative to one another with a drive means as utilised via a crank to 15 raise the foot portion of the bed, the crank being adapted to positively drive the foot portion into a raised position but while the foot portion of the bed is being lowered the drive is adapted to disconnect from its driving position in the event the foot portion becomes blocked. In this arrangement the foot portion is lowered by gravity as the crank is being retracted. 20 BRIEF DESCRIPTION OF THE DRAWINGS In order that the present invention may be more readily understood and be put into practical effect, reference will now be made to the accompanying drawings which illustrate one preferred embodiment of the invention and wherein: 3 Figure 1 illustrates a bed showing the foot portion in its raised position; Figure 2 is an underside view showing the crank and linkage arrangement for raising the foot portion and thigh portion to the position illustrated in Figure 1; 5 Figure 3 is a drawing illustrating the initial stages at which the drive is first engaged; and Figure 4 is a drawing illustrating an intermediate stage at which the foot portion and thigh portion is being raised to the position illustrated in Figure 1. METHOD OF PERFORMANCE 10 Referring to the drawings and initiallyto Figure 1, there is illustrated a bed assembly 10 comprising a mattress 11 having a head end 12, a thigh region 13 and a foot region 14, the thigh region is shown in its inclined position with the foot portion shown in a raised horizontal position. The bed assembly includes a frame assembly 15 having a base frame 16 15 with legs 17, 18 and 19 (it being appreciated that additional legs are provided across the frame) and a sub-frame 20 set on rollers 21 and 22 so that this may move marginally along the guide 23 as the foot end is raised or lowered so that it effectively joggles back and forwards on the main bed frame 16. The thigh and foot portions include support platters at 24 and 25 20 respectively with a linkage arrangement having bilateral links 26 and 27 driven together by a central hydraulic cylinder assembly at 28 with a central crank arm 29 disposed about a rotatable beam 30 coupled to the links 26 and 27. The retraction of the piston 31 and the crank serves to keep the piston under load and thereby retain the thigh and foot sections in the position illustrated in Figure 4 1 in concert with operation of the links and the bilateral connecting arms 32. The connecting arms 32 have stubs 33 adapted to travel a short distance, about 25mm-50mm in slot 34 before the leg and thigh portion are raised. This slightly alters the direction of the applied force so that the central coupling between the 5 links is first raised. This is shown in the retracted position shown in Figure 3 and the extended position shown at Figure 1. In order for the foot portion and thigh portion to be lowered the hydraulic cylinder assembly is adapted to extend and the crank 29 rotates. The crank 29 draws away from the rotatable beam 30 and the thigh and foot section simply 10 falls under gravity following the crank. This will be explained in greater detail below. It will however be appreciated that as the bed falls, that is as the foot end falls that any obstruction such as a limb of a nurse or any other obstruction which may be located in the space between the sub-frame 20 and the linkage 27 will 15 simply block lowering of the foot section while the cylinder assembly 28 extends unimpeded and the crank 29 moves away from the rotatable beam 30. Thus this comprises a safety aspect against jamming under the lowering bed. Figure 2 shows the underside and like numerals have been used to illustrate like features. Again, Figure 2 shows the foot section in its raised 20 position and the beam 30 has fixed to it a guide plate 35 and the crank 29 slides beside the fixed plate to which the crank 29 is pivoted at 36. Referring nowto Figures 3 and 4, it will be seen that upon initial retraction of the piston 31 of the cylinder assembly 28 there will be initial movement of the linkage arm 32 relative to the bracket 37 in the slot 34 and this will be 5 accompanied by a slight forward movement of the sub-frame relative to the base frame. The crank 29 is shown initially slightly separated from the beam 30 and as the piston continues to retract the crank will engage the beam 30 and this relative disposition along with the movement of the stub 33 in the slots 34 on 5 opposite sides of the bed will start to cause the central portion of the linkages at the pivot 38 to move upward in an inverted V and further retraction of the cylinder assembly will cause the stubs 33 to reach the end of the slot 34 and then the foot section will commence its movement towards the horizontal constrained by the arms 32 as at the same time the thigh section is moving to 10 its inclined position until ultimately they reach the position illustrated in Figure 1. Whilst the above has been given by way of illustrative example of the present invention many variations and modifications thereto will be apparent to those skilled in the art without departing from the broad ambit and scope of the invention as herein set forth in the appended claims.

Claims (2)

1. A bed assembly comprising a frame, an articulated foot portion and adjacent thigh portion, the thigh portion and foot portion being moveable relative to one another, the foot portion being moveable firstly and marginally in an axial 5 direction prior to the foot portion being raised.

2. A bed assembly having an articulated foot portion and adjacent thigh portion, the thigh portion and foot portion being moveable relative to one another with a drive means as utilised via a crank to raise the foot portion of the bed, the crank being adapted to positively drive the foot portion into a raised position but 10 while the foot portion of the bed is being lowered the drive is adapted to disconnect from its driving position in the event the foot portion becomes blocked. In this arrangement the foot portion is lowered by gravity as the crank is being retracted.