Repetitive pressure pulse jacket

Information

  • Patent Grant
  • 6254556
  • Patent Number
    6,254,556
  • Date Filed
    Friday, March 12, 1999
    25 years ago
  • Date Issued
    Tuesday, July 3, 2001
    23 years ago
Abstract
A vest for a human body has an air core coupled to a pulsator operable to subject the vest to pulses of air which repetitively applies and releases pressure to the body. The vest has a cover having a pocket accommodating the air core. The pulsator has diaphragms connected to a d.c. electric motor with a rotary to reciprocating motion transmitting mechanism operable to generate air pulses in the air core.
Description




FIELD OF THE INVENTION




The invention is directed to a medical device used to apply repetitive compression forces to the body of a person to aid blood circulation, to loosen and eliminate mucus from the lungs of a person, or to relieve muscular and nerve tensions.




BACKGROUND OF THE INVENTION




Artificial respiration devices for applying and relieving pressure on the chest of a person have been used to assist in lung breathing functions, and loosening and eliminating mucus from the lungs. Subjecting the person's chest and lungs to pressure pulses or vibrations decreases the viscosity of lung and air passage mucus, thereby enhancing fluid mobility and removal from the lungs. These devices use vests having air-accommodating bladders that surround the chests of persons. Mechanical mechanisms, such as solenoid or motor-operated air valves, supply air under pressure to the bladders in regular patterns of pulses. J. D. Ackerman et al in U.S. Pat. No. 2,588,192 disclose an artificial respiration apparatus having a chest vest supplied with air under pressure with an air pump. Solenoid-operated valves control the flow of air into and out of the vest in a controlled manner to pulsate the vest, thereby subjecting the person's chest to repeated pressure pulses. W. J. Warwick and L. G. Hansen in U.S. Pat. No. 5,056,505 disclose a chest compression apparatus having a chest vest surrounding a person's chest. A motor-driven rotary valve allows air to flow into the vest and vent air therefrom to apply pressurized pulses to the person's chest.




R. S. Dillion in U.S. Pat. No. 4,590,925 uses an inflatable enclosure to cover a portion of a person's extremity, such as an arm or leg. The enclosure is connected to a fluid control and pulse monitor operable to selectively apply and remove pressure on the person's extremity. R. L. Weber in U.S. Pat. No. 3,672,354 discloses a rest inducing device having an air mattress supplied with air in pulses from an air pump at the frequency of the person's heartbeat.




C. N. Hansen in U.S. Pat. Nos. 5,453,081 and 5,569,170 discloses an air pulsating apparatus for supplying pulses of air to an enclosed receiver, such as a vest and air mattress. The apparatus has a casing with an internal chamber containing a diaphragm. A solenoid connected to the diaphragm is operated with a pulse generator to move the diaphragm to pulse the air in the chamber. A hose connects the chamber with the vest to transfer the air pulses to the vest. This apparatus requires a sizeable solenoid which is relatively heavy and uses considerable electrical power. The solenoid generates heat and noise. The body pulsating apparatus of the present invention overcomes the weight, noise and heat disadvantages of the prior air pulsating apparatus.




SUMMARY OF THE INVENTION




The invention comprises a jacket used to apply repetitive pressure pulses to a human body and a pulsator for generating air pressure pulses that are transmitted to the jacket. The jacket has an outer cover attached to a flexible liner. An air core of flexible material located between the cover and liner is connected with a hose to a pulsator operable to generate sequential air pressure pulses which are transmitted to the air core. The air pressure pulses subjected to the air core create repetitive pressure pulses that are transmitted to the body of a person wearing the jacket. The pulsator has a casing with an internal chamber in air communication with the hose. A diaphragm open to the internal chamber is connected to a motion transmitting mechanism which moves the diaphragm relative to the internal chamber to sequentially increase and decrease the pressure of the air in the internal chamber thereby generating air pressure pulses. An electric motor drives the motion transmitting mechanism which moves the diaphragm. A motor control regulates the speed of the motor to control the air pressure pulse rate.




The preferred embodiment of the pulsator has a casing with an internal chamber with first and second diaphragms. A check valve, such as reed or flapper valve, mounted on the casing allows air to flow into the chamber responsive to movements of the diaphragms. A motion transmitting mechanism driven with an electric motor has a pair of eccentric cams and cam followers connected to the diaphragms operable to reciprocate the diaphragms thereby generating air pressure pulses in the internal chamber. The air pressure pulses are transferred to the air core of the vest which applies repetitive pressure pulses to the body of the person. A motor control regulates the speed of the motor to control the air pressure pulse rate.











DESCRIPTION OF THE DRAWING





FIG. 1

is a diagrammatic view of the body pulsating apparatus located on a body of a person;





FIG. 1

A is an enlarged end view of the right end of the air pulsator of

FIG. 1

;





FIG. 2

is a diagrammatic view, partly sectioned, of the jacket of the body pulsating apparatus of

FIG. 1

;





FIG. 3

is an outside plan view of the jacket of

FIG. 2

;





FIG. 4

is an inside plan view of the jacket of

FIG. 3

;





FIG. 5

is a bottom view of the jacket of

FIG. 4

;





FIG. 6

is a plan view of the inside of the jacket, partly sectioned, showing the air core;





FIG. 7

is a plan view of the air core of the body pulsating apparatus;





FIG. 8

is a bottom view of the air core of

FIG. 7

;





FIG. 9

is a sectional view taken along the line


9





9


of

FIG. 8

;





FIG. 10

is a sectional view taken along the line


10





10


of

FIG. 7

;





FIG. 11

is a sectional view taken along the line


11





11


of

FIG. 9

;





FIG. 12

is an enlarged sectional view of the air pulsator taken along line


12





12


of

FIG. 1

;





FIG. 13

is an enlarged and foreshortened sectional view taken along the line


13





13


of

FIG. 12

;





FIG. 14

is an enlarged sectional view taken along the line


14





14


of

FIG. 13

;





FIG. 15

is a reduced sectional view taken along the line


15





15


of

FIG. 12

; and





FIG. 16

is a foreshortened sectional view taken along the line


16





16


of FIG.


15


.











DESCRIPTION OF PREFERRED EMBODIMENT




The body pulsating apparatus


10


, shown in

FIG. 1

, functions to apply repetitive pressure pulses to a person


11


having an upper body


13


and left and right shoulders


12


and


14


. A diaphragm


16


extends across the body below lungs


17


and


18


.




A jacket


24


located about body


13


has an outside cover


26


joined to an inside liner


27


. Cover


26


is a non-elastic fabric. Liner


27


is an open mesh flexible sheet member secured to outer peripheral edges of cover


26


. Fasteners, shown as stitches


25


in

FIG. 6

, connect liner


27


to cover


26


and a bottom zipper


51


. An air core


28


confined between cover


26


and liner


27


operates to apply repeated fluid, herein air, pressure pulses, shown as arrows


33


and


34


, to body


11


. The frequency of the pulses is variable. The pressure of the air varies between 1 to 3 psi. Air core


28


can be subjected to other air pressures.




An air pulsator


29


connected to jacket


24


with air hose


31


delivers air under pressure to air core


28


. Hose


31


is connected to a tube


32


attached to jacket


24


. The end of hose


31


telescopes over tube


32


to releasably connect hose


31


to jacket


24


. The air pressure delivered to air core


28


periodically increases and decreases to apply pressure pulses to body


13


. The details of pulsator


29


are hereinafter described.




As shown in

FIG. 3

, jacket


24


has a pair of upright shoulder straps


36


and


37


laterally separated with a concave upper back edge


38


. Upright front chest portions


39


and


46


are separated from straps


36


and


37


with concave curved upper edges


41


and


47


which allow jacket


24


to fit under the person's arms. Loop pads


42


and


48


secured to the outer surfaces of chest portions


39


and


46


cooperate with hook pads


52


and


53


secured to the insides of shoulder straps


36


and


37


to releasably connect shoulder straps


36


and


37


to chest portions


39


and


46


. As shown in

FIG. 1

, shoulder straps


36


and


37


extend forwardly over shoulders


12


and


14


and downwardly over chest portions


39


and


46


. The hook and loop pads


42


,


48


,


52


and


53


are releasable VELCRO fasteners that connect shoulder straps


36


and


37


to chest portions


39


and


46


and hold chest portions


39


and


46


adjacent the front of body


13


.




Jacket


24


has a first lateral end flap


43


extended outwardly at the left side of jacket


24


. A rectangular loop pad


44


secured to the outside of flap


43


cooperates with hook pads


54


and


56


on a second lateral end flap


49


on the right side of jacket


24


to hold jacket


24


around body


13


. The hook and loop pads


44


,


54


and


56


are VELCRO fasteners that allow jacket


24


to be tightly wrapped around body


13


.




Air core


28


, shown in

FIG. 6

, conforms to the shape and contour of the space between cover


26


and liner


27


. As shown in

FIGS. 7 and 8

, air core


28


has a pair of upright back sections


96


and


97


that fit into pockets in shoulder straps


36


and


37


and upright front sections


98


and


99


that fit into chest portions


39


and


46


. The bottom section


101


of air core


24


is linear and has a length about the length of zipper


51


. Air core


28


has air impervious plastic sheet members


57


and


58


having outer peripheral edges


59


and vertical strips


76


to


87


heat sealed together forming enclosed vertical air chambers


61


to


74


, shown in

FIGS. 9 and 10

. Horizontal strips


89


and


91


are heat sealed together generally parallel to the bottom edge


101


. The bottom ends of vertical strips


76


to


87


are spaced about horizontal strips


89


and


91


providing an air feeder passage


94


open to the bottom ends of air chambers


61


to


74


. The middle sections


88


of sheet member


57


and


58


are sealed together between back air chambers


61


and


67


. Strips


88


and


91


have adjacent ends spaced from each other providing a port


92


between a passage


93


and air feed passage


94


to allow air to flow into and out of air chambers


61


to


74


. The bottom of middle section


88


spaced about port


92


directs air into air feeder passage


94


.




As shown in

FIGS. 1 and 12

, air pulsator


29


has a box shaped case


106


supporting an ON-OFF switch


107


for controlling the operation of a d.c. electric motor


108


. An adjustable control


109


, shown as a dial in

FIG. 1

, functions to control the operating speed of motor


108


which regulates the pulse cycles or frequency of the pulses. For example, control


109


is adjustable to regulate the air pulses between


3


to


15


air pulses per second.




Pulsator


29


has a square tubular body


111


with openings


112


and


113


in opposite walls


114


and


116


. End plates


117


and


118


connected to opposite ends of body


111


close chamber


119


in body


111


and confine motor


108


to chamber


119


. Plates


117


and


118


can be provided with openings to allow air to flow through chamber


119


and motor


108


. Openings


112


and


113


are covered with head plates


121


and


122


. Head plate


121


has a generally rectangular chamber


123


. A generally square diaphragm


124


extended across chamber


123


is clamped to wall


114


with bolts


126


. A variable orifice proportional free-flow valve


128


is connected to end plate


118


to vary the pressure of air in pulsator


29


and jacket


24


. Air hose


31


is connected to end plate


117


. Hose


31


transmit air pulses from pulsator


29


to jacket


24


. The pressure of the air in pulsator


29


and jacket


24


is about 1 psi. Other air pressures can be used.




Head plate


122


has a generally rectangular chamber


129


closed with a generally rectangular diaphragm


131


. Bolts


132


clamp head plate


122


and diaphragm


131


to wall


116


. A one-way valve


134


mounted on end plate


118


allows air to be drawn into pumping chamber


119


upon operation of pulsator


29


to inflate the air core


28


in jacket


24


. Valve


134


is a reed-type or flapper-type check valve that allows air to flow into pumping chamber


119


in response to reciprocating movements of diaphragms


124


and


131


and automatically close when the flow of the air attempts to reverse direction. When the air pressure in pumping chamber


119


falls below atmospheric pressure, valve


134


allows additional air to be drawn into pumping chamber


119


. An air pump (not shown) coupled to air hose


31


can be used to supply air under pressure to jacket


24


and pulsator


29


to initially inflate apparatus


10


.




Diaphragms


124


and


131


have the same size and structure. Diaphragm


124


, shown in

FIGS. 15 and 16

, has rigid top and bottom plates


136


and


137


. The plates


136


and


137


are plastic members reinforced with glass fibers. An expanded polyvinyl chloride core


138


is sandwiched between plates


136


and


137


. Core


138


is bonded to the inside surfaces of plates


136


and


137


to connect and reinforce plates


136


and


137


. A flexible flange


139


projects outwardly from the outer peripheral edges of plates


136


and


137


. Flange


139


is a rectangular flat member of air impervious flexible material, such as rubber, plastic or metal. The inner portion


141


of flange


139


is located between and secured to plates


136


and


137


. The outer portion of flange


139


has holes


142


for bolts


126


that secure head plate


121


and flange


139


to wall


114


. Flexible flange


139


allows plates


136


and


137


to be laterally moved, as shown as arrows


143


, relative to chamber


119


to pulse the air in chamber


119


.




Diaphragm


131


has the same structures as diaphragm


124


including rigid plates


144


and


146


, foam core


147


and flexible flange


148


, shown in FIG.


12


. Flexible flange


148


allows plates


144


and


146


to be laterally moved, as shown by arrows


149


, relative to chamber


119


to pulse the air in chamber


119


.




A motion transmitting mechanism, indicated generally at


151


in

FIG. 12

, drivably connected to motor


108


converts rotary motion to reciprocating motion to linearly move diaphragms


124


and


131


relative to chamber


119


. This causes the air in chamber


119


to pulse by repetitively increasing and decreasing air pressure as diaphragms


124


and


131


are forced into and out of chamber


119


. Chamber


119


can be partially filled with solid filler material (not shown) to reduce the clearance volume in chamber


119


and thereby increase the magnitude of the air pulse.




Motion transmitting mechanism


151


has a pair of circular cams


152


and


153


keyed to motor drive shaft


152


. As shown in

FIGS. 12 and 14

, cams


152


and


153


eccentrically mounted on shaft


154


move cam followers


156


and


157


in opposite linear directions. Cams


152


and


153


have 180-degree eccentricity to balance the forces on cam followers


156


and


157


during rotation of shaft


154


. An ear


158


joined to cam follower


156


is pivotally connected to a yoke


159


with a pin


161


. A layer of adhesive or bonding material


162


secures yoke


159


to the center of diaphragm


124


. Cam follower


157


has an ear


163


connected to a yoke


164


with a pin


166


. Yoke


164


is secured with an adhesive or bonding material to the center of diaphragm


131


. Cam follower


156


has a rectangular opening


167


accommodating cam


152


and upper and lower faces


168


and


169


that contact cam


152


. Cam follower


157


has a rectangular opening identical to opening


167


accommodating cam


153


and upper and lower faces that contact cam


153


. Motor


108


operates to rotate cams


152


and


153


which move cam followers


156


and


157


in opposite directions thereby moving diaphragms


124


and


131


in opposite linear directions to pulse air in chamber


119


.




Cam followers


156


and


157


are located in a casing


171


having linear walls


172


and


173


that have flat guide surfaces engageable with opposite sides of cam followers


156


and


157


. Casing


171


has a center rib


174


and end plates


176


and


177


that retain cam followers


156


and


157


in casing


171


. Supports


178


and


179


mount casing


171


on walls


181


and


182


of body


111


to fix the location of casing


171


in chamber


119


.




In use, jacket


24


is placed about the person's body and retained in place with shoulder straps


36


and


37


connected to releasable members


42


and


48


. The circumferential location of jacket is maintained with connected releasable fasteners


44


and


54


,


56


. Air pulsator


29


is connected to vest air input tube


32


with an elongated flexible hose


31


.




The operation of pulsator


29


is commenced to charge the vest and pulsator


29


with air under pressure, such as 1 psi. The air inflates air core


28


. As shown in

FIG. 9

, the air flows through manifold


93


, passage


92


into upright chambers


61


to


74


. The inflated air core


28


holds inside liner


27


in firm engagement with the front, back and sides of the person's body.




Switch


107


is turned ON to start motor


108


which operates the rotary to reciprocating motion transmission mechanism


151


connected to diaphragms


124


and


131


. The frequency of the air pulses is adjusted with motor speed control


109


to provide efficient and effective pulses to the person's body. Diaphragms


124


and


131


increase air pressure in chamber


119


to provide an air pulse in jacket


24


. When diaphragms


124


and


131


are moved inwardly or toward each other the air pressure in chamber


119


is increased to provide the air pressure pulse in jacket


24


. The diaphragms


124


and


131


have rigid plates connected to flexible peripheral flanges which allows linear movements of diaphragms


124


and


131


so that relatively small movements of diaphragms


124


and


131


relative to chamber


119


cause a sufficient change in air pressure in chamber


119


. This air pressure change causes repeated pressure pulses in jacket


24


. The frequency of the pulses generated in jacket


24


can be altered by changing the speed of motor


108


. Control


109


is used to change the speed of motor


108


to alter the frequency of movements of diaphragms


124


and


131


which control the frequency of the air pulses. Also, reducing the clearance volume of chamber


119


can increase the magnitude of the air pressure pulse.




The present disclosure is a preferred embodiment of the body pulsating apparatus. It is understood that the body pulsating apparatus is not to be limited to the specific materials, constructions and arrangements shown and described. It is understood that changes in parts, materials, arrangement and locations of structures may be made without departing from the invention.



Claims
  • 1. A combined jacket for applying repetitive pressure pulses to a human body and a pulsator for generating air pressure pulses which are transmitted to the jacket comprising: a jacket adapted to be placed about the body of a person, said jacket having an outer cover, a flexible liner attached to the cover, and an air core located between the cover and liner, a pulsator for generating air pressure pulses, means for carrying air from the pulsator to the air core whereby the air core is subjected to air pressure pulses generated by the pulsator, said pulsator including a casing having an internal air chamber, said means for carrying air being in communication with the air chamber, diaphragm means connected to the casing open to the internal air chamber, a motor having a drive shaft, a motion transmitting mechanism located within the internal air chamber drivably connecting the drive shaft of the motor to the diaphragm means operated in response to rotation of the drive shaft to move the diaphragm means relative to the air chamber to increase and decrease the pressure of the air in the air chamber thereby generating repetitive air pressure pulses, and means for supplying air to said internal air chamber to provide the air core with air.
  • 2. The jacket and pulsator of claim 1 wherein: the motion transmitting mechanism includes a cam eccentrically secured to the drive shaft, a cam follower engageable with the cam, means connecting the cam follower to the diaphragm means, and guide means engageable with the cam follower to limit movements of the cam follower to linear reciprocating movements.
  • 3. The jacket and pulsator of claim 1 wherein: the diaphragm means includes rigid plate means and a flexible flange secured to the plate means, means connecting the flange to the casing, means connecting the motion transmitting means to the rigid plate means to laterally move the plate means relative to the air chamber to generate air pressure pulses in said air chamber.
  • 4. The jacket and pulsator of claim 1 wherein: the casing includes a body having first and second openings, said diaphragm means includes a first diaphragm extended across the first opening, a second diaphragm extended across the second opening, a first head plate, a second head plate, fastening means connecting the first and second diaphragms and first and second head plates to the body, means located within the internal air chamber connecting the motion transmitting mechanism to the first and second diaphragms operable in response to operation of the motor to move the first and second diaphragms relative to the internal air chamber to increase and decrease the pressure of the air in the internal air chamber thereby generating repetitive air pressure pulses.
  • 5. The jacket and pulsator of claim 4 wherein: the first and second diaphragms each have rigid plate means and a flexible flange secured to the plate means, said motion transmitting mechanism being connected to the rigid plate means to laterally move the plate means, said flange being secured to the body with the fastening means.
  • 6. The jacket and pulsator of claim 4 wherein: the first and second diaphragms each have a rigid first plate, a rigid second plate laterally spaced from the first plate, said first and second plates having outer peripheral edges, a core located between and secured to the first and second plates, and a flexible flange secured to the first and second plates, said flange extended outwardly from the outer peripheral edges of the first and second plates to allow lateral movements of the first and second plates, said flange being secured to the body with the fastening means.
  • 7. The jacket and pulsator of claim 6 wherein: the flexible flange has a portion located between and secured to the first and second plates.
  • 8. The jacket and pulsator of claim 4 wherein: the motion transmitting mechanism includes first and second cams eccentrically secured to the drive shaft with the first cam eccentrically positioned 180 degrees from the second cam, a first cam follower engageable with the first cam, means connecting the first cam follower to the first diaphragm, a second cam follower engageable with the second cam, means connecting the second cam follower to the second diaphragm, and guide means engageable with the first and second cam followers to limit movements of the first and second cam followers to linear reciprocating movements.
  • 9. The jacket and pulsator of claim 1 wherein: the air core includes flexible sheet members having a plurality of side-by-side upright chambers for accommodating air, a circumferential manifold passage for receiving air pulses from the pulsator, and at least one opening between the manifold passage and chambers to allow air to flow from the manifold passage to the chambers.
  • 10. The jacket and pulsator of claim 9 wherein: the center of the air core has a middle seal with upright air chambers on opposite sides of the middle seal.
  • 11. The jacket and pulsator of claim 10 wherein: the air core has one opening adjacent the middle seal between the manifold passage and chambers.
  • 12. The jacket and pulsator of claim 1 wherein: said cover has a pair of shoulder straps and chest portions, first releasable means connecting the shoulder straps to the chest portions, first and second end flaps joined to opposite ends of the cover, said end flaps being located in overlapping relation when the cover, liner, and air core are located around the body of the person, and second releasable means connecting the first and second end flaps to hold the liner and air core in contact with the body of the person whereby when the air core is subjected to air pressure pulses repetitive pressure pulses are transmitted to the body of the person.
  • 13. The jacket and pulsator of claim 12 wherein: the air core includes flexible sheet members having a plurality of side-by-side upright chambers for accommodating air, a circumferential manifold passage for receiving air pulses from the pulsator, and at least one opening between the manifold passage and chambers to allow air to flow from the manifold passage to the chambers.
  • 14. The jacket and pulsator of claim 13 wherein: the center of the air core has a middle seal with upright air chambers on opposite sides of the middle seal.
  • 15. The jacket and pulsator of claim 14 wherein: the air core has one opening adjacent the middle seal between the manifold passage and chambers.
  • 16. The jacket and pulsator of claim 1 wherein: the means for supplying air to said internal chamber comprises one-way valve means allowing air to flow into the internal chamber in response to movement of the diaphragm means and preventing air to flow from the internal chamber back through the valve means.
  • 17. A pulsator for generating repetitive air pressure pulses comprising: a body having an internal air chamber, a first diaphragm extending across the air chamber, a second diaphragm extended across the air chamber opposite the first diaphragm, fastening means connecting the first and second diaphragms to the body, a motor, a motion transmitting mechanism located within the internal air chamber connecting the motor to the first and second diaphragms operable to move the first and second diaphragms relative to the air chamber to increase and decrease the pressure of the air in the air chamber between the diaphragms thereby generating repetitive air pressure pulses, means for supplying air to said chamber, the motor having a drive shaft, the motion transmitting mechanism includes first and second cams eccentrically secured to the drive shaft with the first cam eccentrically positioned 180 degrees from the second cam, a first cam follower engageable with the first cam, means connecting the first cam follower to the first diaphragm, a second cam follower engageable with the second cam, means connecting the second cam follower to the second diaphragm, and guide means engageable with the first and second cam followers to limit movements of the first and second cam followers to linear reciprocating movements.
  • 18. The pulsator of claim 17 wherein: the means for supplying air to said air chamber comprises one-way valve means allowing air to flow into the air chamber in response to movement of the diaphragms and preventing air to flow from the air chamber back through the valve means.
  • 19. A diaphragm comprising: a rigid first plate, a rigid second plate laterally spaced from the first plate, said first and second plates having outer peripheral edges, a core located between and secured to the first and second plates, and a flexible flange secured to the first and second plates, said flange extended outwardly from the outer peripheral edges of the first and second plates to allow lateral movements of the first and second plates, the first and second plates being plastic flat members reinforced with glass fibers, said core is an expanded foam plastic secured to members, and said flange is a flexible rubber member having a portion located between and secured to the members.
  • 20. The diaphragm of claim 19 wherein: the flexible flange has a portion located between and secured to the first and second plates.
  • 21. The diaphragm of claim 19 wherein: the first and second plates are flat members having generally the same size and shape.
CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. Provisional Application Ser. No. 60/077,707 filed Mar. 12, 1998.

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Number Date Country
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