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Publication numberUS3885554 A
Publication typeGrant
Publication dateMay 27, 1975
Filing dateDec 8, 1972
Priority dateDec 8, 1972
Also published asCA1002402A, CA1002402A1
Publication numberUS 3885554 A, US 3885554A, US-A-3885554, US3885554 A, US3885554A
InventorsJr Adelbert W Rockwell
Original AssigneeUsm Corp
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Apparatus for generating pulses of fluid pressure
US 3885554 A
Abstract
Apparatus for supplying pulses of fluid pressure to a chamber has means for supplying pressurized fluid to the chamber and means responsive to the pressure of the fluid in the chamber for controlling the supply means to provide pulses of pressure fluid. Additional means for sequentially selecting one of a plurality of such chambers to be supplied with pressure are provided in a preferred embodiment and the control, selecting and sequencing means are fluidic elements.
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United States Patent Rockwell, Jr.

[451 May27, 1975 1 APPARATUS FOR GENERATING PULSES OF FLUID PRESSURE [75] Inventor: Adelbert W. Rockwell, Jr.,

Gloucester, Mass.

[73] Assignee: USM Corporation, Boston, Mass.

[22] Filed: Dec. 8, 1972 [21] Appl. No.: 313,583

[52] U.S. Cl 128/24 R; 128/64; 128/DIG. 10 [51] Int. Cl A61h 1/00 [58] Field of Search 128/24 R, 38-40, 128/60, 64, 33, DIG. 10; 417/474, 475, 394

[56] References Cited UNITED STATES PATENTS 2,071,215 9/1935 Peterson 128/24 R 3,052,238 9/1962 Broman et a1. 417/474 X 3,182,335

5/1965 Bolie 417/394 X Sequence 3,288,132 11/1966 Meredith 128/24 R 3,390,674 7/1968 Jones 1. 128/33 3,494,357 2/1970 Kimball 128/D1G. 10

Primary Examiner-Lawrence W. Trapp Attorney, Agent, or Firm-Ralph D. Gelling; Vincent A. White; Richard B. Megley [57] ABSTRACT 1 Claim, 1 Drawing Figure APPARATUS FOR GENERATING PULSES OF FLUID PRESSURE BACKGROUND OF THE INVENTION The arts of fluid pressure devices are among the oldest known to man. Some have been in continuous use at least from the classic Greek period. In spite of the age of these arts, new developments continue to be made.

One recent contribution is the art of fluidics in which fluid flow is utilized to perform control functions. Devices for performing both logic and sensing control functions are known.

Another recent development is described in US. Pat. No. 3,l79,lo issued Apr. 20, 1965, in the name of Paul A. Meredith. This patent discloses a method and apparatus for preventing venous blood clotting through the application of rapid pulses of minimal external pressure to human body members. The pressure is applied by inflatable bladders fashioned to fit about the body members. The bladders are connected to pressure chambers having mechanically driven diaphragms for generating pressure pulses in the connected bladders. The mechanical diaphragm pressure system is subject to wear. Additionally, the bladders have flexible walls for conforming to body members and for patient comfort. Accordingly, the bladders vary in inflatable volume through the application of body member weight to the flexible walls of the bladder. As the volume of the bladder varies, the pressure generated by particular movement of the pressure generating diaphragm also varys. Since the particular pressure applied to the body members is an important part of the treatment, such a result is undesirable.

An improvement to the apparatus for providing pressure pulses is disclosed in US. Pat. No. 3,307,533 is sued Mar. 7, 1967 in the name of Paul A. Meredith et al. This patent discloses an electro-mechanically driven, rotary valve providing both means for applying pressure to bladders and means for exhausting air from the bladders. Again, no pressure-responsive means are provided and the electromechanical drive requires a source of electric power rendering the apparatus less portable than if such power were not required.

SUMMARY OF THE INVENTION Accordingly, an object of the invention is to provide pressure responsive, portable apparatus for producing pulses of fluid pressure particularly useful for inflating bladders applying pressure to body members.

To this end, the invention has a source of pressurized fluid and means for supplying the pressurized fluid to a chamber which, preferably. is an inflatable bladder. Means responsive to the pressure of the fluid in a chamber controls the supply means to provide a pulse of fluid pressure to the chamber. In a preferred embodiment. means for selecting and means for sequencing among a number of chambers to be supplied with fluid pressure are provided. The preferred embodiment is additionally entirely of fluidic control elements so as to improve portability of the apparatus.

DESCRIPTION OF THE DRAWINGS A preferred embodiment will now be described with reference to a schematic of the embodiment which is intended to be illustrative of and not a limitation on the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The schematic of the preferred embodiment has three cooperatively connected sections. The first section generally indicated at sequences the application of pressure to one bladder 12 ofa plurality ofbladders. A second section of the schematic generally at 14 controls the sequential application of pressure as pulses. A third section of the schematic generally at 16 determines the time between successive, sequential pressure pulses supplied to the bladders. Accordingly, a bladder is selected for inflation by the sequence section of the schematic, the selected bladder pulsed with pressure fluid until the control section 14 terminates the pressure, and the apparatus then remains quiescent until the timing section 16 signals the sequencing section to again select and supply a bladder with pressure. All of the elements of the schematic are fluidic and accordingly may be operated from a source (not shown) of pressure fluid, preferably air, to provide fluid flow control signals at appropriate ports of the elements.

The sequence section has a pair of flip-flops l8 and 20 for selectively driving a series of OR gates 22, 24 and 26 each of which is operatively connected to a valve 28, 30, and 32, respectively, which controls the supply of pressurized air to a bladder. Each of the bladders and valves 28, 30 and 32 is of similar construction and operation; accordingly, only the construction and operation of bladder 12 and connected valve 32 need be described.

An input signal responsive port 34, 36 and 38 of each of the OR gates 22, 24 and 26, respectively, is connected to a one-shot device 40, 42 and 44, respectively, each through an OR gate 46 for power amplification. A signal responsive output of each one-shot 40 and 42 communicates with a control port 46 and 48 of the flipflops 18 and 20, respectively, while a signal responsive output from one-shot 44 communicates with control ports 50 and 52 of the flip-flops 18 and 20, respectively, which ports are complementary to the ports 46 and 48.

The flip-flops 18 and 20 perform the sequencing function. An output port 54 of the flip-flop 18 is responsive to a control. signal at the control port 46 and is connected to an input control port 56 of the OR gate 22 to which a signal at the output port 34 is responsive.

Similarly, an output port 58 responsive to a signal at the input control port 50 of the flip-flop 18 is connected to an input control port of both OR gates 24 and 26 to which a signal at the output ports 36 and 38 is responsive. The flip-flop 20 is similarly connected with an output port 60 responsive to a signal at the control port 48 connected for controlling an output signal at the port 36 and an output port 62 responsive to an input control signal at the port 52 connected for controlling an out put at the port 38. Since each of the flip-flops 18 and 20 continually provide an output signal at one, but only one, of their output ports, the above described connections provide an input control signal to two of the OR gates 22, 24, and 26 in each possible combination of their output signals.

Fluid flow signals from the output ports 34, 36 and 38 are connected to control their respective valves 28, 30 and 32 such that the valves are driven to the left from the position shown in the schematic in response to a signal at the ports. As seen in relation to the valve 32, the pressure fluid input line will then be closed and the pressure line connecting the valve with the bladder 12 will be connected to exhaust to atmosphere. The bladder 12 will then be deflated. On the other hand, when no signal is provided to an input control port of the OR gate 26, the gate provides a normally on output signal at the port 64. The port 64 is connected to an input control port of the valve 32 such that the valve is driven to the position shown in the schematic in which the fluid pressure source is connected to the bladder 12.

Only one bladder 12 is shown in the control section of the schematic 14 because operation of each bladder is similar and only one bladder is sequentially inflated at a time by the sequence section logic. The bladder 12 is also connected to a pressure control port 66 of a Schmitt trigger 68. An adjustable reference pressure is provided at an input port 70 opposing the pressure at port 66. So long as the reference pressure at the port 60 exceeds that at the port 66, the Schmitt trigger provides an output signal only to the exhaust port 72. However, when the pressure in the bladder as applied to the port 66 exceeds the reference pressure at the port 70, the output of the Schmitt trigger switches to the port 74 connected to a flip-flop 76 in the sequence section of the schematic. Adjustment of the reference pressure accordingly adjusts the pressure in the bladder which will trigger a signal to the flip-flop 76.

The Schmitt trigger 68 is physically close to the bladder 12 to maximize pressure sensing sensitivity of the trigger. Longer connecting lines 90 to the trigger require finitely longer real time for fluid pressure to advance from the bladder to the trigger than shorter lines. In addition, elasticity or leakage in the connecting lines may further decrease the pressure sensing sensitivity of the trigger. Accordingly, the trigger is preferably mounted on the bladder. However, operability of the preferred embodiment is not limited to such mounting and the trigger may be grouped with the other fluidic elements remote from the bladder.

A signal at an output port 78 of the flip-flop 76 is responsive to a control signal from the Schmitt trigger. The output port 78 is connected to an input control port of each of the OR gates 22, 24 and 26 so as to complement the gates to provide a signal at their output ports 34, 36 and 38 respectively; of course, only one of the gates 22, 24 and 26 will not already be providing an output signal to its port 34, 36 or 38 under the influence of signals from the flip-flops l8 and at another input control port. Accordingly, only one of the OR gates will actually complement in response to a single signal from the output port 78 of the flip-flop 76. Since the operation of each of the OR gates 22, 24 and 26 is analogous, as already noted, only one need be described.

It may be assumed that the embodiment is in the state illustrated in the schematic in which a signal at the output ports 34 and 36 prevents inflation of the bladders (not shown) connected to the corresponding valves 28 and 3t) and has produced an evanescent signal from the one-shots 40 and 42 which are now selfdisabled. The signal from the one-shots 40 and 42 has appeared at the control ports 46 and 48 of the flip-flops l8 and 20 complementing the flip-flops to provide an output signal at the ports 54 and 60. respectively. which latches the OR gates 22 and 24 with an output signal at their ports 34 and 36. The flip-flops l8 and 20 are bi-stable devices and. accordingly, will not complement from set state until they receive an active. complementing signal.

In contrast to the OR gates 22 and 24, the OR gate 26 has been in its stable condition with an output at its port 64 maintaining the valve 32 in position to supply air to the bladder 12. The signal from the output port 78 of the flipflop 76 then complements the OR gate 26 to provide a signal at its output port 38. The signal at the port 38 complements the valve 32 to block further pressure fluid input to the bladder 12 and to connect the bladder to atmosphere for deflation and, simultaneously, provides a signal to the connected one-shot 44. The one-shot 44 then operates to provide a signal of predetermined time duration to its output port connected to the control ports 50 and 52 of the flip-flops l8 and 20. The signal duration from the one-shot 44, as well as that from the one-shots 40 and 42, is predetermined to be long enough to complement the flipflops l8 and 20 but less than the least time required to inflate one of the bladders so that simultaneous signals from more than one of the one-shots cannot cause an indeterminate state in either of the flip-flops 18 or 20.

The signal to the input control ports 50 and 52 of the flip-flops 18 and 20 complements both of the flip-flops to provide an output at the output ports 58 and 62 for ultimately sequentially selecting a bladder to receive fluid. None of the OR gates 22, 24 or 26 immediately complements, however, as they are already maintained in their unstable condition by the signal from the output port 78 of the flip-flop 76 which continues until the flip-flop 76 is complemented.

The timing circuit 16 provides a complementing sig nal to the flip-flop 76. For this purpose, a timer 80 provides a signal at an output port connected to an input control port of a flip-flop 82. This signal complements the flip-flop 82 to provide an output signal at an output port 84 connected to an input control port of the flipflop 76 complementary in control to the input port connected to the Schmitt FIG. 68. Since the bladder 12 has deflated, the output of the Schmitt trigger 68 has returned to the port 72 and the signal from the port 84 of the flip-flop 82 is thus effective to complement the flip-flop 76. No signal then appears that the output port 78 of the flip-flop 76 and the one of the OR gates 22, 24 and 26 not then otherwise disabled by the flip-flops l8 and 20, OR gate 22 in the state assumed above, returns to its stable output condition. The valve responsive to the stable output of that OR gate moves to the right, as seen in the schematic, to inflate the bladder connected to the valve. For example. the OR gate 26 would provide an output signal at the port 64 to drive the valve 32 to the right.

To avoid an indeterminate condition in the flip-flop 76 and to initiate timing of the cycle ofthc bladder then inflating. the signal from the port 84 of the flip-flop 82 is also conducted to a time delay relay 86 which. after a predetermined time. provides an output pulse signal to an input control port of the flip-flop 82 so as to complement that flip-flop. The predetermined time delay is such as to continue the signal from the flip-flop 82 to the flip-flop 76 long enough to insure complementing of the flip-flop 76 but less than the minimum time required to so inflate any of the bladders as to complement the Schmitt trigger 68. An indeterminate state in the flip-flop 76 is thus avoided. This timing cycle is repeated for the sequential inflation of each bladder.

Since the total real time cycle for inflating and deflating the bladder and a quiescent period between bladder inflations is controlled by the timer 80, the timer is provided with means for adjusting the time interval. In the preferred embodiment, the interval adjusting means is a manually adjustable throttle 88 which may be preset for any interval. Preferably, the interval is such as will provide the cycle of operation described in the above recited U.S. Pat. No. 3,179,106.

This patent additionally describes a longer quiescent period after each of the bladders has been sequentially inflated. For this purpose in an alternative embodiment of the invention, the throttle 88 may be responsive to inflation of a selected bladder to provide a longer timing interval and to inflation of other bladders to provide a shorter interval. For example, the port 64 of the OR gate 26 may be connected to means (not shown) for adjusting the throttle 88 to one predetermined position while the corresponding ports of the OR gates 22 and 24 each adjust the throttle to another predetermined position.

In another alternative embodiment of the invention the number of bladders to be sequentially inflated may be increased or decreased with appropriate expansion or diminution of the sequence logic in section of the schematic. The preferred embodiment will also operate one or more bladders by connecting only the desired number of bladders to one of the valves 28, and 32. Similarly, each of the bladders described may have sev eral discrete sections; for example, a section for embracing each arm of a patient upon whom the apparatus is used.

Still other alternative embodiments are contemplated within the scope of the invention defined by the following claims:

I claim:

1. Apparatus for sequentially supplying fluid pressure to a system of more than two bladders according to a predetermined sequence, said bladders being adapted to apply external pressure to portions of the human body comprising:

A. A source of pressurized fluid connected to each bladder;

B. A valve connected to each bladder for controlling the flow of pressurized fluid thereto;

C. Means in each bladder for sensing the pressure therein;

D. A selector for generating fluid pressure signals for actuating the pressure control valves of the bladders according to the predetermined sequence;

E. Means to receive the pressure from the pressure sensors, compare said pressure with a predetermined value, and generate a fluid pressure signal when a predetermined relation between said pressures exists;

F. Means responsive to the fluid pressure signals from the selector and the pressure comparator to sequentially actuate the valves to inflate and deflate the bladders; and

G. Timing means associated with the pressure comparator to control the overall cycling time of each bladder.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2071215 *Sep 14, 1935Feb 16, 1937Petersen PeterArtificial respiration apparatus
US3052238 *Apr 22, 1958Sep 4, 1962Baxter Laboratories IncPressure flow device
US3182335 *Feb 27, 1963May 11, 1965Univ Iowa State Res Found IncDual-chamber artificial heart
US3288132 *Nov 1, 1963Nov 29, 1966Anthony Myron LBladder structures useful in therapeutic treatment
US3390674 *May 28, 1965Jul 2, 1968Bowles Eng CorpInflatable mattress with fluid amplifier
US3494357 *Feb 5, 1968Feb 10, 1970Sperry Rand CorpFluidic respirator
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4013069 *Oct 28, 1975Mar 22, 1977The Kendall CompanySequential intermittent compression device
US4029087 *Oct 28, 1975Jun 14, 1977The Kendall CompanyExtremity compression device
US4030488 *Oct 28, 1975Jun 21, 1977The Kendall CompanyIntermittent compression device
US4057046 *May 17, 1976Nov 8, 1977Mamoru KawaguchiBlood circulation stimulator
US4388919 *Nov 17, 1980Jun 21, 1983Intermedics Cardiassist CorporationRapid stabilization of external cardiac pulsation
US4419988 *Aug 3, 1981Dec 13, 1983Jobst Institute, Inc.Electronic circuit for a dynamic pressure wave pneumatic control system
US4481937 *Jul 2, 1981Nov 13, 1984The Kendall CompanySequential compression device
US4583522 *Sep 1, 1983Apr 22, 1986Grumman Aerospace CorporationSequentially pressurized flight suit
US4664651 *Mar 1, 1985May 12, 1987The Procter & Gamble CompanySubatmospheric method and apparatus for expanding blood vessels to facilitate puncture with a cannula
US4738249 *Mar 1, 1985Apr 19, 1988The Procter & Gamble CompanyMethod and apparatus for augmenting blood circulation
US4941458 *Oct 3, 1986Jul 17, 1990Taheri Syde AMethod for aiding cardiocepital venous flow from the foot and leg of an ambulatory patient
US5092317 *Jun 29, 1989Mar 3, 1992Avigdor ZelikovskiMethod for accelerating the alleviation of fatigue resulting from muscular exertion in a body limb
US5109832 *Dec 7, 1990May 5, 1992Proctor Richard D JMethod of and apparatus for producing alternating pressure in a therapeutic device
US5188096 *Mar 7, 1991Feb 23, 1993Yoo Young YoonMassage apparatus
US5307791 *Jun 1, 1992May 3, 1994Matsushita Electric Works, Ltd.Air massaging device with a precise pressure control
US5437608 *Oct 19, 1992Aug 1, 1995Jb Research, Inc.Massaging apparatus with sequential vibration
US5575762 *Apr 5, 1994Nov 19, 1996Beiersdorf-Jobst, Inc.Gradient sequential compression system and method for reducing the occurrence of deep vein thrombosis
US5588954 *Apr 5, 1994Dec 31, 1996Beiersdorf-Jobst, Inc.Connector for a gradient sequential compression system
US5725485 *Jun 26, 1996Mar 10, 1998Beiersdorff Jobst, Inc.Connector for a gradient sequential compression system
US5951502 *Nov 15, 1996Sep 14, 1999Kci New Technologies, Inc.Gradient sequential compression system for preventing deep vein thrombosis
US5976099 *Dec 18, 1997Nov 2, 1999Kellogg; Donald L.Method and apparatus to medically treat soft tissue damage lymphedema or edema
US6080120 *Mar 15, 1996Jun 27, 2000Beiersdorf-Jobst, Inc.Compression sleeve for use with a gradient sequential compression system
US6296617Jun 21, 1999Oct 2, 2001Kci Licensing, Inc.Gradient sequential compression system for preventing deep vein thrombosis
US6547749Jul 12, 2001Apr 15, 2003Electromed, Inc.Body pulsating method and apparatus
US6648840Jul 28, 1997Nov 18, 2003Salton, Inc.Microcontroller based massage system
US6786879Jun 24, 1998Sep 7, 2004Kci Licensing, Inc.Gradient sequential compression system for preventing deep vein thrombosis
US7044924Jun 2, 2000May 16, 2006Midtown TechnologyMassage device
US7076993 *Jun 12, 2001Jul 18, 2006Novamedix Distribution LimitedLeakage detection method for a pressurised medical appliance
US7584755Dec 1, 2003Sep 8, 2009Tony ReidMultiple sleeve method and apparatus for treating edema and other swelling disorders
US7767874Nov 28, 2006Aug 3, 2010Telesto Holding, LLCMedical device and process
US7771376Jan 25, 2006Aug 10, 2010Midtown Technology Ltd.Inflatable massage garment
US8202237Jun 19, 2012Electromed, Inc.Portable air pulsator and thoracic therapy garment
US8460223Jun 11, 2013Hill-Rom Services Pte. Ltd.High frequency chest wall oscillation system
US8591439 *Aug 13, 2012Nov 26, 2013AutoCPRExtended term patient resuscitation/ventilation system
US20030126912 *Jun 12, 2001Jul 10, 2003Gordon CookLeakage detection method for a pressurised medical appliance
US20040111047 *Dec 1, 2003Jun 10, 2004Tony ReidMultiple sleeve method and apparatus for treating edema and other swelling disorders
US20080125688 *Nov 28, 2006May 29, 2008Telesto Holdings, LlcMedical device and process
US20080154163 *Mar 13, 2008Jun 26, 2008Tony ReidMultiple sleeve method and apparatus for treating edema and other swelling disorders
USD639954Jun 14, 2011Electromed, Inc.Thoracic garment
USRE40814Jun 30, 2009Hill-Rom Services, Inc.Oscillatory chest compression device
DE2648513A1 *Oct 27, 1976May 5, 1977Kendall & CoVorrichtung zur erzeugung einer auf eine gliedmasse eines patienten einwirkenden kompressionskraft
DE3228977A1 *Aug 3, 1982Feb 17, 1983Jobst InstituteElektrische steuerschaltung fuer eine massagevorrichtung
EP0574333A1 *Jun 8, 1993Dec 15, 1993O.E.R.E.C. S.a.r.L.Massage device with inflatable chambers for applying alternating pressure
WO1997028375A1 *Jan 29, 1997Aug 7, 1997Joseph LonjonMonitoring and control device for alternately supplying a fluid to a plurality of receiving members
Classifications
U.S. Classification601/150, 128/DIG.100
International ClassificationA61H23/04
Cooperative ClassificationY10S128/10, A61H2201/5056, A61H9/0078
European ClassificationA61H9/00P6