FR2702957A1 - Fluidized bed mattress for medical use with integrated decontamination means. - Google Patents

Abstract

The invention provides a fluidized bed mattress (10), in particular for medical use, of the type comprising a tank (12) open at its upper face, in which a dense suspension of particles is created in an ascending fluid stream and which is covered by at least one envelope fabric (24), characterized in that it comprises integrated means (26) for decontaminating the particles, constituted for example by electrical resistors (26) making it possible to ensure decontamination by heating particles.

Description

The present invention relates to a fluidized bed mattress, in particular to

  medical use The invention relates more particularly to a mattress of the type comprising a tank, open at its upper face, in which a suspension is created

  dense of particles in an ascending fluid stream

  dant and which is covered by at least one canvas

envelope-

  Such a type of fluidized bed mattress, also called fluidized bed, is commonly used in the medical field for certain therapies, and certain

  patients, and for example in the case of patients with

badly burned.

  In fact, the use of such a mattress makes it possible to distribute the pressures on the face of the body as regularly and as homogeneously as possible.

  of the patient who is resting on the envelope fabric.

  It is necessary that such a mattress, like other objects for medical use, be the cleanest

  possible and presents sterility conditions ne-

  of the therapies used, especially in the case of burn victims

  It is of course possible to sterilize directly

  the upper envelope fabric is

  to replace it as an element

  disposable, either by sterilizing it, for example by boiling

  or by subjecting it to radiation.

  Insofar as the mass of particles contained in the tank is in repeated and almost permanent contact with the inner face of the covering fabric, the

  particles are themselves contaminated with colo-

  nies of microorganisms It is therefore necessary to

  ability to decontaminate fluidized bed.

  So far, this decontamination operation

  tion, especially when changing patients, was done by replacing the mass of particles with a

  mass of clean particles, the tank not being

  contaminated This par renewal operation

  ticules is a particularly long and difficult operation to carry out It is moreover little adapted to the medical environment, in particular when the bed

  is located in a sterile room He was then born

  stop having powerful suction means, or move the bed out of the sterile room to replace without causing pollution

sterile environment.

  In order to remedy the drawbacks which have just been mentioned, the invention provides a mattress for

  fluidized bed of the type mentioned above, characteristic

  laughed at in that it includes integrated means of

particle contamination.

  According to other characteristics of the invention, the decontamination means include heating means integrated into the tank,

  the heating means include resistances

  electrical tanks arranged in the tank and means for supplying electrical energy to the resistors; the resistors extend longitudinally inside the tank; the resistors are supported by a plate

  perforated intermediate arranged in the tank, near

  from the bottom; the intermediate plate has parts in relief relative to its general plane, which support the resistances;

  the heating means include resistances

  tances, each in the form of a hairpin, which extend parallel from a side face

  end of the tank and which are connected in parallel

  the the; the electrical energy supply means include a thermostatic regulation circuit

  with a decontamination temperature probe

  tion arranged in the tank; the means for supplying electrical energy comprise means for displaying the decontamination temperature; and the electrical energy supply means comprise at least one safety device for the

  control of the energizing of the heating means

fage-

  Other features and advantages of the

  ventin will appear on reading the description

  detailed below for understanding the-

  which will be referred to the attached drawings in the-

which:

  Figure 1 is a schematic perspective view

  tive with partial tearing, which illustrates an embodiment of a fluidized bed mattress in accordance with the teachings of the invention; FIG. 2 is a diagram illustrating the electrical wiring of the components contained in the tank; and FIG. 3 is an electrical diagram illustrating part of the control circuit for the supply of

  electrical energy of resistors and means of

  indication of the decontamination temperature-

  The fluidized bed mattress 10 shown diagrammatically in FIG. 1 is essentially constituted by a tank

  in mechanically welded stainless steel sheet 12.

  The tank 12 has a generally parallel shape

  pipedic rectangle whose upper face is or

  green upwards and is bounded by an edge 14-

  The tank has two end side walls

  mite 16 and two longitudinal walls 18 and a

rectangular background 20-

  According to a known arrangement, the bottom 20 is doubled by a fluidization plate 22 which defines therewith a fluidization chamber which is connected to a pump (not shown) which makes it possible to inject a fluid under pressure into the chamber, the fluidization plate made of microperforated polyethylene In operating condition, the vessel 12 is filled

  fine particles (not shown) which, in combination

  ciation with the fluidization chamber, and according to a

  known technique, allow a fluid bed to be produced

  said to consist of the mass of suspended particles

sion in the pressurized fluid.

  The upper face of the tank is covered by a flexible closing cloth 24 which constitutes the

  upper fabric of the fluidized bed mattress on the

  which the patient rests directly, or with interpo-

  sition of fabrics and / or intermediate sheets.

  According to the invention, the tank 12 is equi-

  mass of in situ decontamination of the mass

particles.

  These means consist of resistors

  electric 26, three in number, each of which pre-

  feels a hairpin shape that stretches out

  gitudinally inside the tank from one

  lateral end faces 16.

  Resistors 26 rest on an inter-

  perforated medium 28 which is fixed in the tank to

near the bottom.

  The plate 26 has a series of holes, of square or circular section, or can also be produced in the form of a grid, at least 50 X of the surface of the grid being perforated so as not to disturb the operation of the bed. fluidized The intermediate plate 28 has raised ribs 30, which are here transverse ribs

  of substantially square section, on which rest

  feels the resistors 26 which are fixed there by

mounting lugs 32.

  The presence of the ribs 30 makes it possible to prevent the heat produced by the resistors from being absorbed too much by the metal of the plate.

intermediate 28.

  The two ends of each of the resistors 26 open onto the outside of the tank where they are connected to electrical wires 34 for supplying current protected against heat. The resistors 26 are thus connected to means for supplying electrical energy, and decontamination control circuits, which are arranged in a power supply and control unit shown schematically in the figure and designated

by reference 40.

  The visible face of the block 40 comprises for example display means 42, a display pressure gauge 44

  fluidization pressure, at least one interrupt

  key key 46 and a cover 48 allowing access to a

circuit breaker-

  The technical block 40 contains means of transformation, command and regulation including

  only some will be described later.

  Figure 2 illustrates the wiring diagram.

  wiring of the three resistors 26 contained in the tank 12 which are here resistors supplied with 220

  Volts and which dissipate each 1100 Watts maximum.

  A probe 50 for measuring the decontamination temperature is also provided in the tank.

protected by a cover.

  The resistors 26 and the probe 50 are connected to the block 40 by a socket 52 at ten points of 16 amps at

380 Volts.

  An adjustable three-phase thermostat 54, for example

  from 30 to 80 'C, is interposed in the supply circuit

resistance 26.

  Partially shown in FIG. 3 is the circuit for controlling the energization of the resistors.

tances 26, from block 40.

  This circuit includes three switching devices

  tion arranged in series which constitute as many

  safety positives to avoid start-up

  accidental heating means for deconta-

  mination. These devices consist of a contactor 56 connected to the circuit breaker covered by the cover 48, a switch 58 and a second switch 60 controlled by the key lock 46 The resistors are energized by successively actuating these three devices 56 to 60 .

  A power supply circuit has also been shown.

  tion of a programmable display 62 to display the decontamination temperature measured by the probe 50. When an operator, for example a nurse, wishes to proceed with the decontamination of the particles, he starts the fluidization circuit so as to proceed with a brewing of the particles and then it puts

  under tension the resistors 26 by acting successively

  on devices 56, 58 and 60 so that

  cause heating of the particles in situ internally

inside of the tank.

  The decontamination cycle continues, the case

  automatically if necessary, thanks to a temperature circuit

  risation (not shown) until the particu-

  be clean again The tank itself is

  decontaminated after heating operations.

  7, The decontamination of the particles can be made even more homogeneous in the case where the fluidization control circuit includes a regulation circuit to produce a variable fluidization which is obtained, for example using a digital frequency converter and programmable By acting on a graduated potentiometer, it is then possible to vary the frequency of the motor supply current, for example from 25 to 60 Hz, and therefore the speed

  of the motor and thus the flow of the fluidization pump

  tion. The thermal block 40 is produced in the form of an autonomous block which is fixed to the structure of the bed,

  or detached from it to be set up in the former

  interior of the room and constitute an autonomous block

remote control.

  A flexible screen, not shown, is also provided above the resistances which allows, at the end

  decontamination operations to remove impurities-

  tees and dust, lifting the sieve which 1

  flow out the particles but which retains the impurities-

  The screen itself decontaminated is then replaced and returns to position in the bottom under

the effect of its own weight.

  Many variations are possible without

  depart from the scope of the present invention.

  The different control and regulation circuits

  tion may in particular include means for varying the temperature produced inside the

  tank by the resistors during a decon-

  tamination as well as the different durations of the

  of the cycle, as well as the viscosities of fluid

  disation by acting on the frequency inverter of the

engine-

  The invention which has just been described makes it possible to ensure, integrated into the fluidized bed mattress, a function of in-situ decontamination of the particles, during a change of patient or after a given period of use of the bed, killing by heating

colonies of microorganisms.

  The integrated resistors can also be used to vary the actual temperature of the fluidized bed mattress, in normal use of the latter, of the control and regulation circuits.

  independent and provided with adequate security

  laying down, being provided for this purpose.

Claims (3)

  1 fluidized bed mattress (10), in particular for medical use, of the type comprising a tank (12), open to   its upper face, in which is created a sus-   dense board of particles in an upward flow of fluid and which is covered by at least one covering fabric (24), characterized in that it comprises   integrated means (26) for decontaminating particles   the 2 fluidized bed mattresses according to claim 1 characterized in that the decontamination means include heating means (26) integrated into the tank (12) -   3 fluidized bed mattress according to claim   2, characterized in that the heating means   carry electrical resistances arranged in the tank (12) and means for supplying electrical energy to the resistors (26) 4 fluidized bed mattress according to claim   3, characterized in that the resistors (26) extend   tooth longitudinally inside the tank (12) -   Fluidized bed mattress according to claim 4, characterized in that the resistors (26) are supported by an intermediate plate (28) perforated arranged in the tank (12) 6 Fluidized bed mattress according to claim, characterized in that the plate intermediate (28) has raised portions (30), relative to its   general plan, which support the resistances (26) -   T fluidized bed mattress according to any one   claims 3 to 6, characterized in that the   heating means include resistors, each   cune in the shape of a hairpin, which extend parallel to each other from a lateral end face (16) of the tank (12) and which are connected in parallel.   8 fluidized bed mattress according to any one of claims 3 to 7, characterized in that the means for supplying electrical energy comprise   a thermostatic regulation circuit (54) comprising   both a decontamination temperature sensor (50)   tion. 9 fluidized bed mattress according to any one of claims 3 to 8, characterized in that the means for supplying electrical energy comprise   means (62) for displaying the temperature of the   contamination. Fluidized bed mattress according to any one   claims 3 to 9, characterized in that the   electrical energy supply means comprise at least one safety device (56, 58, 60) for controlling the energization of the heating (26).