EP0967903B1

EP0967903B1 - Support structure for bed bases

Info

Publication number: EP0967903B1
Application number: EP97940109A
Authority: EP
Inventors: Stefano Gandolfi; Giancarlo Pontoni
Original assignee: Esperides SRL
Current assignee: Esperides SRL
Priority date: 1997-02-17
Filing date: 1997-08-14
Publication date: 2001-09-12
Anticipated expiration: 2017-08-14
Also published as: IT1290723B1; DE69706711T2; WO1998035591A1; JP2001512335A; ES2164369T3; DE69706711D1; EP0967903A1; ITUD970034A1; CA2279921A1; AU4206697A

Abstract

A support structure for bed bases (11), comprising a plurality of elastic slats (1), bars or strips positioned transversely to the bed frame (12) and connected to it via slat-carrying rocker joints (6), and a plurality of hydraulic jacks (2) positioned at least in a central region of the bed base (11) and connecting the rocker joints (6) to the frame (12). The hydraulic jacks (2) are connected together longitudinally to form a hydraulic circuit (3) operating on the basis of communicating vessels. By utilizing the phenomenon of pressure equalization, the pistons (15, 30) of the jacks (2) react to the pressures exerted by the body distended on the bed base (11), to compensate the hollowing created by the heavier parts of the body, i.e. those situated between the shoulder and pelvis, with an upward thrust for supporting the lighter parts, i.e. the back and kidneys.

Description

This invention relates to a structure support for bed bases.
The evolution of the human species, distinguished by the upright position, has led to the evolvement of the vertebral column into a particular S shape.
Although on the one hand this is excellent for the practicality of its movements and the distribution of the loads which it has to support, it on the other hand makes it vulnerable to painful disorders (lumbar and cervical arthroses, dorsalgia, lumbalgia, lumbar sciatalgia, discal hernia, kyphosis, scoliosis etc.).
To prevent these disorders developing, and possibly to forestall them, it is fundamental to use bed bases which enable the vertebral column to maintain, when distended, the same orientation which it possesses when in the upright position.
In this respect, bed bases without these characteristics compel the vertebral column to assume incorrect positions, so contributing to an increase in painful disorders with consequent automatic stiffening of muscles in their vain attempt to correctly position the vertebral column.
Various types of bed bases are currently available commercially.
A first type is represented by the traditional metal bed base or spring base, consisting of a perimetral frame to which a metal mesh, usually of spring steel, is fixed for elastically supporting the mattress.
The structure involves large thicknesses so that it remains taut within the perimetral frame and hence gives the base rigidity. Such a bed base has certain advantages, such as long life and excellent transpiration. However with the passage of time the structure elasticity decreases considerably and the base sinks in the manner of a hammock, with consequent unnatural positioning of the vertebral column.
A second type of bed base consists of a rigid plank or board comprising a perimetral frame on which a strong wooden panel, sometimes perforated, rests. This arrangement prevents the typical sinking of metal mesh bases but does not adapt to the various shapes of the vertebral column, besides offering poor or very poor transpiration.
A modification of this type of bed base is the rigid slat base, which behaves essentially as the rigid plank or board, but provides better transpiration.
In contrast, the elastic slatted bed base comprises a plurality of slats positioned transversely to a frame and connected to it by insertion or elastic joints. The slats are elastic and upwardly curved, making them elastically yieldable.
They become further yieldable if fixed to the frame via suitable elastic dampers positioned usually in the shoulder region.
The elasticity of individual slats can be adjusted by applying to them the principle of leaf-spring suspensions.
In this case, excellent adaptability to the natural curves of the vertebral column is achieved, enabling the heavier parts of the body (shoulders and pelvis) to sink and the lighter parts (back and kidneys) to be more greatly supported. Transpiration is also good.
However this system reacts passively to the stresses of a distended body, being firstly influenced by its weight and, in its operability, by the most usual rest position (prone, supine, sideways, etc.). Its implementation is therefore personalizable. but is not self-adjusting and is also poorly self-modelling.
Finally, water beds or mattresses are known, consisting essentially of a container on which there is positioned a mattress constructed of impermeable material and containing water. This mattress can be divided into one or more chambers, either connected together or mutually independent.
A mattress of this type well adapts to the anatomy of a distended body, but does not adequately support the vertebral column, as it also tends to create a hammock effect. Moreover it has no transpirability, its weight is considerable (more than 200 kg per bed place) and it requires continuous maintenance to prevent proliferation of bacteria and/or mildew in the liquid.
Furthermore, support structures, in particular for hospital beds, comprising a plurality of hydraulic jacks and having the features of the preamble of claim 1 are disclosed in DE-B-1 260 092 and in DE-A-2 832 584.
An object of the present invention is therefore to obviate the aforesaid drawbacks relative to the known art, and in particular to provide a support structure for bed bases which enables orthopedically correct support to be achieved for the vertebral column, with the further possibility of obtaining active reaction of the bed base to the anatomy of a distended body.
A further object of the present invention is to provide a support structure for bed bases which enables the muscular system to relax while at the same time maintaining body temperature within an ideal microclimate.
A further object of the present invention is to indicate a support structure for bed bases which forestalls and counteracts incorrect positions of the vertebral column and enables this latter even when distended to maintain the same arrangement as in its upright position.
A further object of the present invention is to indicate a support structure for bed bases which enables high hygienic conditions to be maintained, with protection against mites, bacteria, mildew and dust, often a cause of allergic disorders.
A further object of the present invention is to provide a support structure for bed bases which is of easy and low-cost construction, without using complex techniques or costly components.
These and further objects are attained according to the present invention by a support structure for bed bases in accordance with claim 1, to which reference should be made for brevity.
Advantageously, the support structure of the present invention enables the mutually connected transverse slats of a bed base to react actively to the weight exerted by the different anatomical areas of a distended body, with an upward thrust of equal intensity, equally distributed throughout the entire length of the bed base.
The structure comprises a frame, consisting of a central support body, from which there emerge a plurality of piston rods or cylinders, each of which, for its operation, cooperates with a jack and to the top of which there is pivoted a rigid profiled beam. The operating chambers of at least one row of jacks are connected together via a closed circuit within which a fluid travels.
A pair of flexible slats are connected to the beam via rubber rocker joints.
A perimetral support frame can also be used. In this case. the rods of the jacks, fixed to the frame, support rocker joints, to which the slats are connected.
It should be noted that generally slats, bars or strips can be used, as can jacks of piston and rod type, or expansion chamber type or bellows type.
The vertical travel of each jack rod is such as to enable the bed surface to adapt to the anatomy of the body, by accommodating the heavier and more voluminous regions such as the shoulders and pelvis, and energetically supporting those which require greater support, such as the lumbar region, irrespective of the weight and shape of the person resting on it. This is achieved by utilizing the principle of communicating vessels and pressure equalization, such that with the lowering of one or more slats or a part of them there corresponds the raising of other slats.
Hence the bed base and mattress actively interact, to adapt to each other and ensure full attainment of the stated objects. Preferably the bed base of the present invention is constructed of steam-pressed multi-layer flexible slats of curved beech-wood, which because of their constant elasticity with time adhere perfectly, section by section, to the curves of the vertebral column, yielding only where necessary and enabling this latter to maintain an orthopedically correct arrangement in every position assumed by the body during sleep.
Alternatively the slats can be constructed of wooden block or another convenient elastic material, including plastic materials reinforced, for example, with glass fibres, and in any event the greater the number of slats the more effective is their action.
In a preferred embodiment, the slats are connected via rocker joints of indeformable anti-impact material to a strong frame entirely of wood, to prevent electromagnetic signals propagating throughout the structure, to ensure quality of sleep.
Moreover, the strong insulating frame totally excludes creaking, does not produce rust, and safeguards the mattress integrity. Advantageously, the jacks and the hydraulic circuit formed by them are positioned exclusively in the central part of the bed base. Two rows of jacks can also be provided, positioned at the two ends of the slats, so that the entire slat is raised or lowered by compensation.
According to a further embodiment, the row of jacks is single or multiple, arranged longitudinally to the bed base, with the slat ends either remaining in a fixed aligned position or being supported by a plurality of rows of jacks. If fixed at their ends, there is height compensation only in the central parts of the respective slats.
The characteristics and advantages of a support structure for bed bases according to the present invention will be more apparent from the description thereof given hereinafter by way of nonlimiting example with reference to the accompanying schematic drawings, on which:
Figure 1 is a schematic perspective view of a slatted or barred frame for bed bases;
Figure 2 is a partial schematic cross-section of Figure 1, at least partly showing the support structure for bed bases of the present invention in the rest position;
Figure 3 is a partial schematic cross-section of Figure 1, at least partly showing the support structure for bed bases of the present invention, when stressed by the weight of a body;
Figure 4 is a perspective view of a support structure for bed bases, according to the invention;
Figure 5 is a schematic side view of a support structure for bed bases, according to the present invention, when stressed by the weight of a body;
Figure 6 is a schematic side view of a jack associated with a pair of slats, and used in the support structure for bed bases, according to the present invention;
Figure 7 is a schematic front view of a jack associated with a pair of slats, and used in the support structure for bed bases, according to the present invention;
Figure 8 is a front view of a slat rocker joint used in the support structure for bed bases, according to the invention;
Figure 9 is a side view of the slat rocker joint of Figure 8;
Figure 10 is a plan view of the slat rocker joint of Figure 8;
Figure 11 is a view of the slat rocker joint of Figure 8 from the rear;
Figure 12 is a partly sectional side view of a first embodiment of a jack used in the support structure for bed bases, according to the invention;
Figure 13 is a plan view of a plate for fixing jacks to frames for bed bases;
Figure 14 is a front view of a second embodiment of a jack used in the support structure for bed bases, according to the present invention;
Figure 15 is a side view of the jack of Figure 14;
Figure 16 is a plan view of the jack of Figure 14;
Figure 17 is a view of the jack of Figure 14 from above;
Figure 18 is a front view of a piston with relative slat connector, which are used in the jack of Figure 14, according to the present invention;
Figure 19 is a side view of the piston with relative slat connector of Figure 18;
Figure 20 is a view of the piston with relative slat connector of Figure 18, taken from above;
Figure 21 is a view of a bayonet cover for the jack of Figure 14, taken from above.
In the said figures, the reference numeral 1 indicates a series of arched bars or strips or slats inserted into a frame 12 to form a bed base 11 acting as a support for a mattress, and to which the support structure of the present invention is applied.
In the ensuing description only the term "slats" will be used, this also embracing the other embodiments provided relative to transverse planks, bars or strips arranged on a bed base 11.
The present invention also provides for the use of two different types of frame 12, namely a perimetral frame such as that shown in Figure 1, in which the slats 1 are contained within the frame 12, and an underlying frame 12 in which the slats 1 bound the perimeter of the bed base 11, the frame 12 having smaller dimensions than the slats 1 and being constructed in an underlying position such as shown in Figure 4.
The reference numeral 2 indicates a plurality of jacks, and 3 indicates overall a hydraulic connection circuit between the jacks 2 which operates on the physical principle of communicating vessels.
It should again be noted that the jacks 2, applied to the frame 12, can be connected together in one, two or more rows arranged laterally or centrally to the bed base 11, the slats 1 being aligned and being slidingly fixed to the ends of the bed base 11 by known devices.
It is however important to emphasize that optimum operation of the support structure according to the present invention is achieved for the condition in which the jacks 2 and the hydraulic circuit 3 are positioned exclusively in a central region of the bed base 11, corresponding to a mattress region which supports the vertebral column, locatable substantially where, when in the prone, supine or side positions, those body parts between the shoulders and pelvis usually rest.
In this respect, if the hydraulic circuit 3 extends over the entire bed base 11, the operability of the support structure for correct support of the vertebral column would be prejudiced, as the lighter body parts, such as the head and legs, would be urged upwards and the central body part, which is heavier, would sink into the bed base 11 into a position similar to that assumed by the body when laying on a hammock.
With particular reference to Figures 6-13, the reference numeral 4 indicates a rigid profiled beam to which the jack 2 is fixed via a support plate 5 positioned within a housing 7, and 6 indicates a slat carrier joint free to rock about a fulcrum 10 and comprising two first seats 8 into which slats 1 are inserted and a second seat 9 into which the profiled beam 4 is inserted.
In the embodiment of Figure 12, the jack 2 comprises a main rod 13 and two secondary rods 14 positioned diagonally to the main 13; 15 indicates a piston of the jack 2, and 17 and 18 indicate two holes for entry of air and fluid respectively into the jack 2.
In this specific case, the jacks 2 are single-acting, with an internal return spring 19; obviously,they can alternatively be formed as bellows or without a piston 15, or as a simple expansion chamber as illustrated schematically in Figures 2 and 3.
The reference numerals 131 and 141 indicate respectively means for fixing the main rod 13 and the secondary rods 14 to the plate 5, and 77 indicates a U-shaped housing, provided below the plate 5 in the casing 16 of the jack 2, for fixing the jack 2 to the frame 12 of the bed base 11 by fixing means 70.
Finally, the reference numeral 20 indicates means for fixing the plate 5 to the profiled beam 4.
Alternatively, the jack 2 can be formed as in Figures 14-21, in which 23 indicates overall that side of the jack 2 which is fixed to the frame 12, 22 indicates the fixing pins, 24 indicates an inlet connector for the fluid to the jack 2, and 26 indicates a groove provided in an upper region of the jack 2 for the forced insertion of a bayonet cover 27. The cover 27 is semi-circular, with two profiled appendices 29 and a central space 28, enabling air to enter.
In this embodiment, the jack 2 comprises a piston 30 provided with a rod 31 and housed within a cylinder 35, and a slat connector 32 comprising stiffeners 34 and two pins 33 for mounting traditional slat carrier joints; finally, 40 indicates a space for housing pins for fixing to slat carrier joints of traditional type.
The support structure for bed bases 11, according to the present invention, is able to combine the advantages of a bed base 11 comprising elastic slats, elasticity regulator joints and dampers, with the possibility of obtaining an active reaction of the bed base 11 to the anatomy of a distended body.
The slats 1, positioned transversely to the frame 12, are connected to it by the traditional slat carrier joints which, in the central part of the bed base 11, ie that part where the body parts between the shoulders and pelvis usually rest, are connected to the frame 12 via hydraulic jacks 2.
These jacks 2 are connected together longitudinally to form a hydraulic circuit 3 operating on the communicating vessel principle.
It is therefore apparent that by utilizing the principle of communicating vessels and pressure equalization, the pistons 15, 30 of the jacks 2 react to the pressures exerted by the distended body to compensate the hollowing of the bed base 11 created by the heavier parts of the body, with an upward thrust supporting the lighter parts.
In this respect, by causing the rod 13, 14, 31 of a piston 15, 30 of the jack 2 to retract, an advancement thrust is necessarily created for the other rods 13, 14, 31 and vice versa, in any form of combination; this allows absolute adaptability to the shape of the vertebral column, enabling this latter to maintain its most natural arrangement even when distended, independently of the weight of the body resting thereon and of its rest position.
The frame 12 is either constructed perimetrally to the slats 1 or is positioned below them.
The bed base 11 is formed either with a longitudinal single-beam support frame or with a double-beam support frame.
The longitudinal single-beam support frame consists of a metal frame 12 comprising two pressed sheet metal shells within which there is positioned a single row of hydraulic jacks 2, the rod 13, 14 of which supports the centre of the T-shaped profiled beam 4 positioned transversely to the frame 12; by way of slat-carrying rocker joints 6 the beam 4 supports a pair of slats 1; if the slats 1 are constructed of elastic material, substantially small cross-sections can be used for equal bending strength, eight jacks 2 being preferably used, all in line.
The jacks 2 used, of which the rod 13, 14 has a total travel of 10 centimetres, have technical characteristics which are totally special and innovative, such that the rod 13, 14 does not rotate, so preventing the slats 1 touching each other, and such that the piston 15 slides within the cylinder 35 with the same fluidity, both when the pressure is exerted at the centre of the T formed by the profiled beam 4, which is pivoted to the piston 15, and when the pressure is exerted at the ends of said T.
Consequently the pistons 15 are formed with three rods 13, 14, namely a large-diameter main rod 13 which is pivoted to a large-thickness piston 15 within the casing 16 of the cylinder 35.
The main rod 13 emerges from the cylinder 35 via an exit port 352, likewise of large thickness, to make it little sensitive to transverse forces. A further two secondary rods 14 of smaller diameter positioned diagonally to the main rod 13 slide within a further two cylinders 351, provided within the structure present external to the cylinder 35.
The three rods 13, 14 are fixed to a plate 5 which represents the support base for the profiled beam 4 supporting the bed base 11. The plate 5 is positioned within the housing 7, provided below the profiled beam 4, in correspondence with the head of the jack 2.
In this manner a piston 15 is obtained, the main rod 13 of which does not rotate and which slides with extreme fluidity, even when the pressure of a distended body is exerted in correspondence with the ends of the T.
An embodiment alternative to the single-beam frame 12 is represented by a double-beam support frame. This comprises two longitudinal beams arranged laterally to the bed base 11, as in Figure 1, to which the hydraulic jacks illustrated schematically in Figures 14-21 are fixed by fixing pins 22.
Each slat 1, positioned transversely to the frame, is fixed by slat carrier joints of known type to the head of the connector 32 of each jack.
The connector 32 is positioned at the top of the rod 31 of the piston 30. The slat carrier joints are mounted on the pins 33 and made flexible or rocking by rubber rings inserted in the spaces 40. Each row of jacks in this case forms an independent hydraulic circuit. Two hydraulic circuits 3 are provided. one for each longitudinal beam, and each preferably composed of eight hydraulic jacks positioned in pairs at the sides of each individual slat.
It should again be noted that in this embodiment, optimum operation of the support structure for the bed base 11 is obtained on condition that the jacks and the hydraulic circuits formed by them are positioned exclusively in a central region of the bed base 11, in correspondence with a mattress region which supports the vertebral column of a distended body.
The connection head 32 of the rods 31 in formed in such a manner as to. enable nearly all those slat carrier joints currently available on the market to be easily applied. Moreover, this applicational arrangement considerably reduces the jack production costs and the total construction cost of the support structure for the bed base 11, compared with the known art and compared with the previously described jack construction.
The present arrangement also enables different bed base models 11 to be obtained by simply using slat carrier joints of one, two or three seats and characterised by different degrees of flexibility.
In this respect, joints flexible in a vertical direction, joints flexible in a horizontal direction, joints flexible in a horizontal and vertical direction, and rocker joints can be mentioned.
Finally, it is apparent that as in this embodiment two jacks are used for each slat 1, this arrangement is not influenced by transverse loads, which in contrast are present in the previously described embodiment, neither are there any problems regarding rotation of the jack rod 31.
The characteristics of the support structure of the present invention are apparent from the aforegoing description, as are its resultant advantages. and in particular:

active support for the vertebral column;
adequate user comfort;
good transpiration;
substantial lightness of the entire structure;
low cost in relation to the advantages obtained.

Finally, it is apparent that numerous other modifications can be made to the support structure for bed bases of the present invention without leaving the novel principles of the inventive idea, it being also clear that in the practical implementation of the invention the materials, the shapes and dimensions of the illustrated details can be chosen according to requirements and can be replaced with others technically equivalent.

Claims

A support structure for bed bases (11) comprising at least one frame (12) for supporting at least one mattress, via a plurality of bars or strips or slats (1) arranged transversely to said frame (12) and connected to it by a plurality of hydraulic jacks (2) or expansion chambers arranged in rows in a substantially central region of said bed base (11), characterised in that said hydraulic jacks (2) are connected together by a closed line, in which a fluid flows so as to form a hydraulic circuit (3) and so that by utilizing the principle of communicating vessels and pressure equalization, said structure reacts to the pressure exerted by a distribution of loads of a body distended on said mattress by compensating the lowering of at least one or parts of said slats (1) created by heavier portions of said body compared with lighter portions with the raising of other slats (1) or parts of them, said fluid being incompressible and entirely filling said hydraulic circuit (3) characterised in that said frame (12) is provided in a position below said slats (1), such that they bound the perimeter of said bed base (11), said frame (12) being of lesser dimensions than said slats (1) and comprising
A support structure as claimed in claim 1, characterised in that said frame (12) is provided in a position below said slats (1), such that they bound the perimeter of said bed base (11), said frame (12) being of lesser dimensions than said slats (1) and comprising two longitudinal planks to which said hydraulic jacks (2) are fixed by fixing means (22).
A support structure as claimed in claim 1, characterised in that said slats (1) are constructed of non elastic and/or flexible material or of wood.
A support structure as claimed in claim 3, characterised in that said wooden material is of multi-layer beech construction or of curved and pressed multi-layer beech construction.
A support structure as claimed in claim 1, characterised in that each of said hydraulic jacks (2) supports at least one profiled beam (4), positioned transversely to said frame (12) and fixed to a plurality of said slats (1), said profiled beam (4) supporting a pair of slats (1) by way of at least one flexible or rocker joint (6).
A support structure as claimed in claim 5, characterised in that each of said hydraulic jacks (2) comprises one piston (15) and three rods (13, 14), fixed to a plate (5) housed below said profiled beam (4), of which one constitutes a main rod (13) and it is of greater diameter than the other two secondary rods (14).
A support structure as claimed in claim 6, characterised in that said two secondary rods (14) are positioned diagonally to said main rod (13).
A support structure as claimed in claim 7, characterised in that each of said two secondary rods (14) slides within a first cylinder (351), provided externally to a second cylinder (35) within which said main rod (13) slides, said main rod (13) having a total travel of at least 0,1 metres.
A support structure as claimed in claim 2, characterised in that said hydraulic jacks (2) are arranged in two rows located in correspondence with said two longitudinal planks, each of said row being provided with eight hydraulic jacks (2) and two hydraulic jacks (2) being provided for each slat (1).
A support structure as claimed in claim 1, characterised in that each of said hydraulic jacks (2) comprises, at its top, at least one groove (26) for the insertion of a semi-circular bayonet cover (27), comprising two appendices (29), which define a free space (28) enabling said gaseous elements to enter.