Patent Grant
10314753
This disclosure relates generally to fluidized person support structures. More particularly, but not exclusively, one illustrative embodiment relates to fluidizing a fluidizable medium of a fluidized person support structure. While various fluidized person support structures have been developed, there is still room for improvement. Thus a need persists for further contributions in this area of technology.
In one illustrative embodiment, a fluidized person support structure comprises a fluidizable medium, a fluid supply, a sensor, and a controller. The fluid supply is configured to supply fluid that flows through the fluidizable medium. The controller is electrically coupled to the fluid supply and the sensor and is configured to calculate a desirable flow rate as a function of at least one input from the sensor as the rate at which fluid flows through the fluidizable medium is changed. The controller causes the fluid supply to supply fluid at the desirable flow rate.
In another illustrative embodiment, a fluidized person support structure comprises a fluidizable medium, a fluid supply, an input device, and a controller. The fluid supply is configured to supply fluid that flows through the fluidizable medium. The controller is configured to receive an input from the input device and calculate a fluidization threshold as a function of the input. The controller controls the fluid supply as a function of the fluidization threshold.
In another illustrative embodiment, a fluidized person support structure comprises a fluidizable medium, a fluid supply, a sensor, and a controller. The fluid supply is configured to supply fluid that flows through the fluidizable medium. The sensor is configured generate a signal indicative of a level of fluidization of the fluidizable medium. A physical property of the sensor changes as the fluidizable medium is fluidized by the fluid. The controller is configured to receive an input from the sensor and control the fluid supply as a function of the input.
In another illustrative embodiment, a method of fluidizing a fluidizable medium comprises the steps of: identifying a fluidization threshold of the fluidizable medium; and increasing a rate at which fluid flows through the fluidizable medium as a function of the fluidization threshold.
In another illustrative embodiment, a method of fluidizing a fluidizable medium comprising the steps of: changing a rate at which fluid flows through the fluidizable medium; sensing a parameter indicative of a level of fluidization of the fluidizable medium; determining a desirable flow rate as a function of the sensed parameter; and controlling a fluid supply as a function of the desirable flow rate.
Additional features alone or in combination with any other feature(s), including those listed above and those listed in the claims and those described in detail below, can comprise patentable subject matter. Others will become apparent to those skilled in the art upon consideration of the following detailed description of illustrative embodiments exemplifying the best mode of carrying out the invention as presently perceived.
Referring now to the illustrative examples in the drawings, wherein like numerals represent the same or similar elements throughout:
While the present disclosure can take many different forms, for the purpose of promoting an understanding of the principles of the disclosure, reference will now be made to the embodiments illustrated in the drawings, and specific language will be used to describe the same. No limitation of the scope of the disclosure is thereby intended. Various alterations, further modifications of the described embodiments, and any further applications of the principles of the disclosure, as described herein, are contemplated.
A person support apparatus 10 according to one illustrative embodiment of the current disclosure is shown in
The supports 16 are coupled to the lower frame 12 and the upper frame 14 and movably support the upper frame 14 above the lower frame 12 as shown in
The upper frame 14 includes an upper frame weldment 24 that supports a tank assembly 26 or container 26 and a head end support assembly 28 as shown in
The tank assembly 26 includes a tank base 34, a tank liner 36, a tank bladder 38, and a filter cover 40 or gas permeable cover 40 as shown in
The filter cover 40 or filter sheet 40 is positioned over the opening 39 and is coupled to the tank liner 36 as shown in
The diffuser 48 is configured to support the fluidizable medium 46 in the chamber 44 and provide substantially uniform fluid flow to the fluidizable medium 46 as shown in
The volume between the diffuser 48 and the filter cover 40 is filled with the fluidizable medium 46 as shown in
The fluidizable medium 46 is composed of small particles that can vary in shape in size. In one illustrative embodiment, the fluidizable medium 46 are spherical silica beads of the type commonly employed in air fluidized bead person support systems. In some contemplated embodiments, the fluidizable medium 46 can range in size from about 50 to about 150 microns in diameter. A new batch of the fluidizable medium 46 having a depth of about 9 inches requires about 25-35 cubic feet per minute (“CFM”) to reach the fluidization threshold and about 40-65 CFM to provide a desirable level of fluidization.
The fluidization system 18 is configured to communicate fluid, such as, air, through the diffuser 48 to fluidize the fluidizable medium 46. The fluidization system 18 includes a fluid supply 52, a hose 54, a sensor 56, an input device 57, and a controller 58 as shown in
The sensor 56 is configured to measure an operational parameter of the person support apparatus 10 indicative of a level of fluidization of the fluidizable medium 46 as shown in
In another illustrative embodiment, the sensor 56 includes an accelerometer coupled to the tank assembly 26 and positioned in the fluidizable medium 46 as shown in
In another illustrative embodiment, the sensor 56 includes an array of pressure sensors positioned within the fluidizable medium 46 as shown in
In another illustrative embodiment, the sensor 56 includes a pressure sensor positioned in the plenum 50 and configured to measure the pressure within the plenum 50 as shown in
The input device 57 is electrically coupled to the controller 58 as shown in
The controller 58 is electrically coupled to the fluid supply 52 and the sensor 56 and is configured to control the operation of the fluid supply 52 as a function of one or more input signals from the sensor 56. The controller 58 can determine how to optimize fluidization of the fluidizable medium 46 a number of ways. One way the controller 58 can optimize fluidization is by identifying the location of the fluidization threshold and increasing the fluid flow rate by a predetermined amount. In one illustrative embodiment, the controller 58 calculates what the fluidization threshold is based on the depth of the fluidizable medium and the weight of the person supported thereon. In another illustrative embodiment, the fluid flow rate from the fluid supply 52 is slowly increased from an initial flow rate, for example, 0 CFM, until the input from the sensor 56 indicates that the fluidizable medium 46 is at about the fluidization threshold. Once the fluidization threshold has been determined, the controller 58 increases the fluid flow rate by a predetermined amount, such as, 10-35 CFM, to reach a predetermined desirable level of fluidization. The fluidization threshold can be established during a calibration mode or while a person is supported on the person support structure 10.
Another way the controller 58 can optimize fluidization is by checking the fluidization level as the fluid flow rate is varied. In one illustrative embodiment, the fluid supply 52 is supplying fluid at a first rate FR1 and the sensor 56 sense a parameter indicative of a first level of fluidization FL1. The controller 58 changes the fluid flow rate from the first rate FR1 to a second rate SR1 and the sensors sense a parameter indicative of a second level of fluidization SL1. In one illustrative embodiment, the change in fluid flow rate is ±5-10 CFM. The controller 58 compares the first level of fluidization FL1 to the second level of fluidization SL1 to determine what the pressure drop between the two values is. If the pressure drop is relatively small then the fluid supply 52 is operating in the fluidized region of the curve in
If neither the first rate FR2 nor the second rate SR2 cause the fluidizable medium 46 to fluidize, then the controller 58 can increase the fluid flow rate until the fluidization threshold is established and then increase the fluid flow rate by a predetermined amount to reach a desired level of fluidization, or the controller can repeat the process of comparing first and second flow rates and levels of fluidization until one of the flow rates generates a desirable level of fluidization. In some contemplated embodiments, the controller 58 can operate the fluid supply 52 at the lower of the first rate FR1 and the second rate SR1 as long as both rates are at or above the fluidization threshold in the fluidized region. In other contemplated embodiments, once a desirable fluidization threshold has been determined and the fluid supply 52 is operating at the appropriate fluid flow rate, a user is able to increase and/or decrease the flow rate within a predetermined therapeutic range, for example, ±20 CFM, as long as level of fluidization remains above the fluidization threshold or the lower end of a predetermined desirable fluidization threshold.
Another way the controller 58 can optimize fluidization is by adjusting the fluid flow rate upon a triggering event occurring. In one illustrative embodiment, the triggering event occurs when the level of fluidization is less than or equal to a predetermined trigger threshold, such as, the fluidization threshold. The level of fluidization can be measured using any of the sensors 56 previously mentioned and the controller 58 can use any method previously mentioned to return the person support apparatus 10 to a desired level of fluidization. In one example, the controller 58 causes the fluid supply 52 to gradually increase the fluid flow rate until the fluidization threshold is established and then increases the fluid flow rate by a predetermined amount to reach a desired level of fluidization. In another example, the controller 58 measures the level of fluidization at the current rate and compares it to a level of fluidization at a higher rate. If the higher rate produces a desired level of fluidization, the controller 58 maintains the fluid flow rate from the fluid supply 52 at that rate. If not, then the process is repeated until a desired fluidization level is reached.
Many other embodiments of the present disclosure are also envisioned. For example, a fluidized person support structure comprises a fluidizable medium, a fluid supply, a sensor, and a controller. The fluid supply is configured to supply fluid that flows through the fluidizable medium. The controller is electrically coupled to the fluid supply and the sensor and is configured to change the rate at which fluid flows through the fluidizable medium from a first rate to a second rate and calculate a desirable flow rate as a function of a first input from the sensor at the first rate and a second input from the sensor at the second rate. The controller causes the fluid supply to supply fluid at the desirable flow rate.
In another example, a fluidized person support structure comprises a fluidizable medium, a fluid supply, a sensor, and a controller. The fluid supply is configured to supply fluid that flows through the fluidizable medium. The controller is electrically coupled to the fluid supply and the sensor and is configured to calculate a desirable flow rate as a function of at least one input from the sensor as the rate at which fluid flows through the fluidizable medium is changed. The controller causes the fluid supply to supply fluid at the desirable flow rate.
In another example, a fluidized person support structure comprises a fluidizable medium, a fluid supply, an input device, and a controller. The fluid supply is configured to supply fluid that flows through the fluidizable medium. The controller is configured to receive an input from the input device and calculate a fluidization threshold as a function of the input. The controller controls the fluid supply as a function of the fluidization threshold.
In another example, a fluidized person support structure comprises a fluidizable medium, a fluid supply, a sensor, and a controller. The fluid supply is configured to supply fluid that flows through the fluidizable medium. The sensor is configured generate a signal indicative of a level of fluidization of the fluidizable medium. A physical property of the sensor changes as the fluidizable medium is fluidized by the fluid. The controller is configured to receive an input from the sensor and control the fluid supply as a function of the input.
In another example, a method of fluidizing a fluidizable medium comprises the steps of: identifying a fluidization threshold of the fluidizable medium; and increasing a rate at which fluid flows through the fluidizable medium as a function of the fluidization threshold.
In another example, a method of fluidizing a fluidizable medium comprising the steps of: changing a rate at which fluid flows through the fluidizable medium; sensing a parameter indicative of a level of fluidization of the fluidizable medium; determining a desirable flow rate as a function of the sensed parameter; and controlling a fluid supply as a function of the desirable flow rate.
In another example, a fluidized person support structure comprises a fluidizable medium, a fluid supply, a sensor, and a controller. The fluid supply is configured to supply fluid that flows through the fluidizable medium. The controller is configured to identify a fluidization threshold as a function of an input from the sensor as the rate fluid supplied by the fluid supply is changed, and control the fluid supply as a function of the fluidization threshold.
In another example, an apparatus for controlling the fluidization level of a fluidized person support apparatus comprises a fluidizable medium, a fluid supply, an input device, and a controller. The fluid supply is configured to communicate a fluid through the fluidizable medium. The controller is configured to receive an input from the input device and calculate a fluidization threshold as a function of the input. The controller controls the fluid supply as a function of the fluidization threshold.
In another example, an apparatus for controlling the fluidization level of a fluidized person support apparatus comprises a fluidizable medium, a fluid supply, a sensor, and a controller. The fluid supply is configured to communicate a fluid through the fluidizable medium. The sensor is configured generate a signal indicative of a level of fluidization of the fluidizable medium. A physical property of the sensor changes as the fluidizable medium is fluidized by the fluid. The controller is configured to receive an input from the sensor and control the fluid supply as a function of the input.
In another example, a method of optimizing fluidization of a fluidizable medium in a person support structure comprises the steps of: upon the occurrence of a triggering event, determining a fluidization threshold of the fluidizable medium; and changing a rate at which fluid flows through the fluidizable medium as a function of the fluidization threshold.
In another example, a method of optimizing fluidization of a fluidizable medium comprises the steps of: identifying a fluidization threshold of the fluidizable medium; and increasing fluidization of the fluidizable medium by a predetermined amount above the fluidization threshold to reach a desired fluidization level.
Any theory, mechanism of operation, proof, or finding stated herein is meant to further enhance understanding of principles of the present disclosure and is not intended to make the present disclosure in any way dependent upon such theory, mechanism of operation, illustrative embodiment, proof, or finding. It should be understood that while the use of the word preferable, preferably or preferred in the description above indicates that the feature so described can be more desirable, it nonetheless can not be necessary and embodiments lacking the same can be contemplated as within the scope of the disclosure, that scope being defined by the claims that follow.
In reading the claims it is intended that when words such as “a,” “an,” “at least one,” “at least a portion” are used there is no intention to limit the claim to only one item unless specifically stated to the contrary in the claim. When the language “at least a portion” and/or “a portion” is used the item can include a portion and/or the entire item unless specifically stated to the contrary.
It should be understood that only selected embodiments have been shown and described and that all possible alternatives, modifications, aspects, combinations, principles, variations, and equivalents that come within the spirit of the disclosure as defined herein or by any of the following claims are desired to be protected. While embodiments of the disclosure have been illustrated and described in detail in the drawings and foregoing description, the same are to be considered as illustrative and not intended to be exhaustive or to limit the disclosure to the precise forms disclosed. Additional alternatives, modifications and variations can be apparent to those skilled in the art. Also, while multiple inventive aspects and principles can have been presented, they need not be utilized in combination, and various combinations of inventive aspects and principles are possible in light of the various embodiments provided above.
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| Child | 14329746 | US |
