Pneumatic lift
A pneumatic lift including at least three jacking-mattresses stacked one atop another and arranged in air flow communication with one another. At least one of the jacking-mattresses is also arranged in air flow communication with a source of pressurized air.
This application is related to, and claims the benefit of U.S. provisional patent application Ser. No. 60/530,161, filed Dec. 17, 2003, and entitled Pneumatic Lift.
FIELD OF THE INVENTIONThe present invention generally relates to devices suitable for lifting living creatures and, more particularly, to a pneumatic lift suitable for use in vertically moving living creatures.
BACKGROUND OF THE INVENTIONThere is a need for a compact, lightweight and easily portable patient lifting device to assist caregivers in lifting prone patients from a lower position, e.g., the floor, to a relatively higher position, e.g., a bed, table, gurney, or vehicle, etc.; for use in the home, in institutional settings, and in the outside world. Transferring of disabled patients is a leading cause of injury in the health-care industry, with the nursing occupation having among the highest incidence of back injury, despite the prior art and the availability of commercial patient lifts. These lifts are under-utilized for a number of reasons, such as restricted space in many hospital wards and bathrooms, cumbersome operating requirements, the indignity involved in the mode of transport, the additional time required for performing the transfer, and the unavailability of the lift at both the patient's starting and destination locations. In addition, many patients are essentially home-bound due to the unavailability of a conveniently portable lift, reducing their quality of life unnecessarily. A device is required that is simple to set up and use, feels safe, secure and is not intimidating for the patient, and can be transported with the patient.
This problem is pervasive in the home health care industry as well, where spaces are not designed for safe patient transfers, and the caregiver is often alone and has no help during lifts. Since conventional lifts are available in less than ten percent of the homes visited by home health care professionals, a device that can be easily brought from home to home is also required. In addition, most prior art lifting devices do not provide for the reduction of hip and back deflection during lifting. This is a significant problem, since if a person's hip or back is already injured, such uncontrolled deflections could exacerbate the existing condition, or possibly cause additional injury.
While this field contains considerable prior art, these devices have proven inadequate. For example, U.S. Pat. No. 4,805,248, issued to Lunau is typical of ceiling-mounted patient lifts. While effective, these are limited to use in very well defined areas. U.S. Pat. No. 3,137,011, issued to Fischer is representative of a common type of mobile patient lift. A major disadvantage of this design is that the patients are essentially suspended from a hook. The resultant swaying motion during transfer is disconcerting to most patients. In addition, the patient is transported in a partially reclined position, increasing their sense of helplessness and indignity, particularly if used outside in public.
U.S. Pat. No. 3,914,808, issued to Woods teaches the use of a short flexible sling in a front-loading orientation, with a pivoting column. The base must be relatively wide in order to avoid tipping as the column is rotated, and there is no means for compactly transporting or storing the lift. Additionally, the use of a fixed length sling requires that the patient be sitting precisely on the center of the sling, to avoid tipping the patient as the column is raised. This increases the time and training required to use the lift.
Pneumatically inflatable, and hydraulically expandable lifting bags are also known. For example, DE-U-1,897,870 discloses an extendable or inflatable lifting device having a pressure release valve assembly. U.S. Pat. No. 3,695,582, issued to Clay discloses a lifting jack for motor vehicles which uses fluid pressure for operating power to raise the wheel of a vehicle. The jack relies upon a pair of stacked hollow flexible plastic bags that may be filled with a suitable fluid.
In U.S. Pat. No. 5,606,785, issued to Shelberg et al., an inflatable air mattress positioner is provided for use with a casket, coffin or alternative container. The assembly includes a partially pneumatic pillow with a chamber in which is disposed a plurality of air chambers, each one of which has a corresponding air tube and valve assembly. A cushion coacts with the air bladders to position the head, upper arm, chest and shoulder region of a cadaver so that the cadaver chin is disposed in an acceptable proper height in relation with the chest. The assembly includes an inflatable air mattress having a plurality of air chambers which are independently inflatable to position a cadaver at an appropriate height and angle in the casket. Additional separate independent air bladders are also provided to be disposed under the cadaver to aid in positioning the cadaver and tilt the cadaver along its longitudinal axis for mourner viewing as well as positioning the back, arms, head, neck or any other part of the cadaver that requires adjustment.
In the U.S. Pat. Nos. 4,688,760, 4,786,032, 4,993,736, 5,651,149, and 5,669,086, all issued to Garmen et al., a variety of lifting apparatus are provided that include a base, a platform disposed above the base, a thrust mechanism positioned between the platform and the base to lift the platform with respect to the base. Garmen et al. often choose a pneumatic thrust mechanism in the form of stacked bellows including a flexible wall composed of substantially inelastic material and having a vertically spaced horizontal stiffener. The bellows include an inlet to allow a gaseous material to inflate each bag for applying lifting forces to the platform. U.S. Pat. No. 6,199,827, issued to Rimington, et al., also discloses an extendable or inflatable lifting device.
None of the foregoing patents adequately address the problem of insuring that a lift is available at both a patient's starting and final locations. Patient transfer mattresses are also well known in the art which include at least two flexible material sheets, that together define a plenum chamber, with at least one sheet being completely perforated with small pinholes over its surface area, and which open up directly to the interior of the plenum chamber. Such prior art mattresses are used by arranging the perforated sheet so that it faces an underlying fixed, generally planar support surface, such as a floor or table. When the mattress is charged with pressurized air, the escape of air under pressure through the pinholes acts initially to jack a load placed upon the mattress (i.e., to lift the load in increments) and thereby creates an air bearing of relatively small height between the underlying fixed, generally planar support surface and the perforated flexible sheet.
For example, in U.S. Pat. No. 4,517,690, issued to Wegener, an air pallet is disclosed that is formed from upper and lower thin flexible film sheets sealed at their edges to form a plenum chamber. Wegener's air pallet functions to move a load with minimal friction over an underlying generally planar fixed support surface. The bottom thin flexible material sheet is perforated by small diameter perforations such as pin holes.
In U.S. Pat. No. 4,417,639, issued to Wegener, a pair of relatively rigid planar members are arranged overlying each other, and are coupled about their edges by a flexible film band to form a jacking plenum chamber. The upper planar member functions as the load support, having a gas inlet hole adjacent one edge. Gas under pressure enters an end of the jacking plenum chamber and escapes through the outer end which allows for jacking of the load. Wegener's design is only capable of jacking the load, e.g., a patient lying on the mattress, several inches above the underlying support surface.
SUMMARY OF THE INVENTIONThe present invention provides, in its broadest aspects, a pneumatic lift including at least two jacking-mattresses stacked one atop another, where the jacking-mattresses are arranged in air flow communication with one another.
In one embodiment, each of the jacking-mattresses includes a top panel having a width, a length, a peripheral edge, a bottom panel having the same width, length, and a peripheral edge, and a perimeter band extending between the top panel and the bottom panel. The peripheral edges of the top and bottom panels are sealingly fastened to one another to form the jacking-mattress. The peripheral band defines at least one through-hole for air flow communication with the interior of at least one other jacking-mattress. A plurality of baffle-panels are also provided each having a width and a length and being attached to an inner surface of the top panel and an inner surface of the bottom panel so as to be transversely oriented between the top panel and the bottom panel. In this way, the baffle-panels define a pair of longitudinally extending air flow passageways disposed between an edge of the baffle-panels and an interior surface of the perimeter band. At least one conduit is arranged in air flow communication between the at least one through-hole in adjacent jacking-mattresses. A source of pressurized air is arranged in airflow communication with one of the at least one through-holes so as to be in airflow communication with the interior of one of the jacking-mattresses.
In another embodiment of the invention, a pneumatic lift is provided that includes a top jacking-mattress, a bottom jacking-mattress, and a plurality of intermediate jacking-mattresses that are stacked one atop another between the top jacking-mattress and the bottom jacking-mattress. Select ones of the jacking-mattresses are arranged in air flow communication with one another. Each of the jacking-mattresses includes a top panel having a width, a length, a peripheral edge, where select ones of the intermediate jacking-mattresses have a top panel having at least one through-hole. A bottom panel is provided having the width, the length, and a peripheral edge, where corresponding select ones of the intermediate jacking-mattresses have a bottom panel having at least one through-hole. A perimeter band extends between the top panel and the bottom panel of each of the jacking-mattresses such that the peripheral edges of the top and bottom panels are sealingly fastened to one another. A plurality of baffle-panels are provided where each has a width and a length and is attached to an inner surface of the top panel and an inner surface of the bottom panel so as to be transversely oriented between the top panel and the bottom panel. Together, the baffle-panels and the perimeter band define a pair of longitudinally extending air flow passageways disposed between an edge of the baffle-panels and an interior surface of the perimeter band. A source of pressurized air is arranged in airflow communication with the interior of at least one of the jacking-mattresses.
In a further embodiment of the invention, a transportable pneumatic lift is provided including a plurality of jacking-mattresses stacked one atop another with selected ones of the jacking-mattresses being arranged in internal air flow communication with one another. A transfer mattress forms a bottom most jacking-mattress. The transfer mattress includes a top panel having a width, a length, and a peripheral edge and a bottom panel having the same width, the same length, and a peripheral edge. A plurality of pinholes are defined in a central portion of the bottom panel. An outer perimeter band extends between the top panel and the bottom panel such that the peripheral-edges of the top and bottom panels are sealingly fastened to one another. A plurality of baffle-panels are attached to an inner surface of the top panel and an inner surface of the bottom panel so as to be transversely oriented between the top panel and the bottom panel. An inner perimeter band extends between the top panel and the bottom panel and enclosing the plurality of baffle-panels so as to define an annular air flow passageway disposed between the outer perimeter band and the inner perimeter band. The inner perimeter band also encloses the baffle-panels thereby forming individual chambers between the baffles. The annular air flow passageway is in flow communication with the individual chambers. A source of continuous pressurized air is arranged in flow communication with the annular air flow passageway.
BRIEF DESCRIPTION OF THE DRAWINGSThese and other features and advantages of the present invention will be more fully disclosed in, or rendered obvious by, the following detailed description of the preferred embodiment of the invention, which is to be considered together with the accompanying drawings wherein like numbers refer to like parts and further wherein:
This description of preferred embodiments is intended to be read in connection with the accompanying drawings, which are to be considered part of the entire written description of this invention. The drawing figures are not necessarily to scale and certain features of the invention may be shown exaggerated in scale or in somewhat schematic form in the interest of clarity and conciseness. In the description, relative terms such as “horizontal,” “vertical,” “up,” “down,” “top” and “bottom” as well as derivatives thereof (e.g., “horizontally,” “downwardly,” “upwardly,” etc.) should be construed to refer to the orientation as then described or as shown in the drawing figure under discussion. These relative terms are for convenience of description and normally are not intended to require a particular orientation. Terms including “inwardly” versus “outwardly,” “longitudinal” versus “lateral” and the like are to be interpreted relative to one another or relative to an axis of elongation, or an axis or center of rotation, as appropriate. Terms concerning attachments, coupling and the like, such as “connected” and “interconnected,” refer to a relationship wherein structures are secured or attached to one another either directly or indirectly through intervening structures, as well as both movable or rigid attachments or relationships, unless expressly described otherwise. The term “operatively connected” is such an attachment, coupling or connection that allows the pertinent structures to operate as intended by virtue of that relationship. In the claims, means-plus-function clauses are intended to cover the structures described, suggested, or rendered obvious by the written description or drawings for performing the recited function, including not only structural equivalents but also equivalent structures.
Referring to
Bottom panel 6 comprises a head portion 22, a foot portion 24, and a peripheral edge 26, and is also formed from a sheet of nylon scrim or the like, that may also be coated on at least its outer surface with a water proof coating. Inner surface 29 of bottom panel 6 may also be coated with a water proof coating as well. Perimeter band 7 extends between peripheral edges 16 and 26, and circumferentially around top panel 4 and bottom panel 6, so as to enclose a central chamber 27 and thereby form each jacking-mattress 3. Through-bores 30 are defined in the portions of perimeter band 7 that lie between head portions 12,22 and foot portions 14,24. Peripheral edges 16 and 26 may have fastening means attached them, such as a conventional zipper mechanism 31, snaps, or the like. A plurality of inlet/outlet fixtures 32 are positioned within through-bores 30 in the central portion of perimeter band 7 (
Referring to
A pneumatic lift 1 is assembled according to the present invention in the following manner. Two, three, four, or more jacking-mattresses 3 are each individually assembled by laying out a bottom panel 6 on a suitable support surface so that baffle-panels 8 may be transversely arranged along the length of inner surface 29. Once in this position, bottom edge 42 of each baffle-panel 8 is fixedly fastened to inner surface 29 of bottom panel 6. Each baffle-panel 8 is often heat sealed along the interface between bottom edge 42 and inner surface 29 of bottom panel 6. This heat sealing may be done with the application of heat or ultrasonic energy at the interface between bottom edge 42 and inner surface 29. Once a plurality of baffle-panels 8 are fastened to inner surface 29 of bottom panel 6, top panel 4 is arranged in overlying confronting relation to bottom panel 6 so that head portion 12 of top panel 4 is confronting head portion 22 of bottom panel 6 and foot portion 14 of top panel 4 is confronting foot portion 24 of bottom panel 6. Once in this position, each top edge 40 of each baffle-panel 8 is fixedly fastened to the inner surface of top panel 4. In order to complete construction of each jacking-mattress 3, it is necessary to sealingly fasten peripheral edge 16 of top panel 4 and peripheral edge 26 of bottom panel 6 to corresponding edges of perimeter band 7. In one embodiment, conventional zipper mechanisms 31 are fastened to peripheral edges 16 and 26 so that several jacking-mattresses 3 may be stacked, one upon another, and releaseably secured to one another by zippers 31 (
Pneumatic lift 1 is operated in the following manner. An object to be lifted, e.g., a human being, is placed atop outer surface 18 of top most jacking-mattress 3, while pneumatic lift 1 is in a fully or partially deflated state (
Referring to
For example, internally situated jacking-mattresses 123 may have common walls forming top panel 104 and bottom panel 106 such that only one through-hole is formed between select panels in order to provide for airflow communication between the select central chambers 27. Fittings 124 may be disposed within openings 52 so as to maintain a fully open configuration during inflation. Referring to
Additionally, another alternative jacking-mattress 143 includes a top panel 144, a bottom panel 146, a perimeter band 147, and a plurality of internally disposed, longitudinal baffle-panels 148 (
Referring to
The patient may be transferred from a fully inflated jacking-mattress using transfer mattress 160 by first inflating the jacking-mattress, as described hereinabove, and then inflating transfer mattress 160. Once inflated, and positioned adjacent to another surface, e.g., a bed, a nurse or other health care worker need merely to slide transfer mattress 160 off of the jacking-mattress to position the patient atop the bed. Once atop the bed, transfer mattress 160 may be deflated so as to position the patient on the bed.
In some cases, it will be necessary to transport the patient while they are lying atop the jacking-mattress. Referring to
In a preferred embodiment, a jacking-mattress 185 comprises a transfer mattress 187 having a top sheet 190, a bottom sheet 192, an outer perimeter band 194, an inner perimeter band 196, and a plurality of internally disposed, transverse baffle-panels 198 (
When transfer mattress 187 is charged with pressurized air, plenum chamber 208 is filled with air first. Central chamber 202 fills with air via through-holes 197 in inner perimeter band 196. In this way, an annular portion of bottom sheet 192 bulges outwardly so as to form a skirt that surrounds that portion of bottom sheet 192 that comprises pinholes 200. The escape of air under pressure through pinholes 200 acts to lift already inflated jacking-mattress 185, which may then be slid along the ground on a cushion of air created by pinholes 200.
It is to be understood that the present invention is by no means limited only to the particular constructions herein disclosed and shown in the drawings, but also comprises any modifications or equivalents within the scope of the claims.
Claims
1. A pneumatic lift comprising:
- at least three jacking-mattresses stacked one atop another wherein at least two of said jacking-mattresses are arranged in internal air flow communication with one another.
2. A pneumatic lift according to claim 1 wherein each of said jacking-mattresses comprise a top panel having a peripheral edge and a bottom panel having a peripheral edge with a perimeter band sealed to and extending between said peripheral edges so as to define an internal chamber.
3. A pneumatic lift according to claim 2 wherein said internal chamber houses a plurality of spaced apart transverse baffle-panels that extend between said top panel and said bottom panel.
4. A pneumatic lift according to claim 2 wherein said top panel and said bottom panel are formed from a sheet of nylon scrim that is coated on at least an outer surface with a water proof coating.
5. A pneumatic lift according to claim 2 wherein an inner surface of said top and bottom panels is coated with a water proof coating.
6. A pneumatic lift according to claim 2 wherein said peripheral edges include cooperative means for fastening said peripheral edges together.
7. A pneumatic lift according to claim 2 wherein said perimeter band defines fluid flow inlet/outlet fixtures that are sealingly positioned therethrough so as to controllably communicate with said internal chamber.
8. A pneumatic lift according to claim 7 wherein said inlet/outlet fixtures comprises a valve that sealingly accepts an air supply hose from a source of flowing air.
9. A pneumatic lift according to claim 3 wherein each of said baffle-panels comprise a substantially rectangular sheet that is transversely fastened to a portion of an inner surface of said top panel and an inner surface of said bottom panel.
10. A pneumatic lift according to claim 9 wherein each of said baffle panels includes end edges that are arranged in spaced relation to an inner facing surface of longitudinally extending portions of said perimeter band.
11. A pneumatic lift according to claim 10 including a pair of longitudinally oriented air flow channels.
12. A pneumatic lift according to claim 10 wherein each of said baffle panel end edges comprises a curve.
13. A pneumatic lift comprising:
- at least four jacking-mattresses stacked one atop another wherein select ones of said jacking-mattresses are arranged in internal air flow communication with another of said jacking-mattresses; and
- a source of pressurized air arranged in airflow communication with said select ones of said jacking-mattresses thereby to sequentially inflate all of said jacking-mattresses when an object is placed upon a top most one of said jacking-mattresses.
14. A pneumatic lift according to claim 13 wherein each of said jacking-mattresses is fixedly fastened to an adjacent jacking-mattress.
15. A pneumatic lift according to claim 14 wherein each of said jacking-mattresses comprises a top peripheral edge and a bottom peripheral edge that are bonded to one another so as to form an air tight interface extending around the top and bottom perimeter of said adjacent jacking-mattresses.
16. A pneumatic lift according to claim 15 wherein said jacking mattresses include a top panel and a bottom panel with at least one through-hole being defined between internally positioned top panels and bottom panels, said through-holes being arranged so as to allow for free air flow communication between adjacent jacking-mattresses.
17. A pneumatic lift according to claim 13 each of said jacking-mattresses is fixedly fastened to an adjacent jacking-mattress.
18. A pneumatic lift according to claim 14 wherein each of said jacking-mattresses comprises a top peripheral edge and a bottom peripheral edge that are bonded to one another so as to form an air tight interface extending around the top and bottom perimeter of said adjacent jacking-mattresses.
19. A pneumatic lift according to claim 15 comprising a top jacking-mattress and a bottom jacking-mattress and at least one intermediate jacking mattress positioned between said top jacking-mattress and said bottom jacking mattress wherein a bottom wall of said top jacking-mattress and a top wall of said at least one intermediate jacking-mattress are common.
20. A pneumatic lift according to claim 15 comprising a top jacking-mattress and a bottom jacking-mattress and at least one intermediate jacking mattress positioned between said top jacking-mattress and said bottom jacking mattress wherein a top wall of said bottom jacking-mattress and a bottom wall of said at least one intermediate jacking-mattress are common.
21. A pneumatic lift according to claim 20 comprising fittings disposed within openings that are defined through said top wall and said bottom wall of said at least one intermediate jacking-mattress so as to maintain a fully open configuration during inflation.
22. A pneumatic lift comprising:
- a plurality of jacking-mattresses stacked one atop another wherein select ones of said jacking-mattresses are arranged in internal air flow communication with one another, each of said jacking-mattresses comprising; a top panel having a width, a length, a peripheral edge; a bottom panel having said width, said length, and a peripheral edge; a perimeter band extending between said top panel and said bottom panel such that said peripheral edges of said top and bottom panels are sealingly fastened to one another, said peripheral band defining at least one through-hole;
- a plurality of baffle-panels each having a width and a length and being attached to an inner surface of said top panel and an inner surface of said bottom panel so as to define air flow passageways;
- at least one conduit arranged in air flow communication between said at least one through-hole in adjacent jacking-mattresses; and
- a source of pressurized air arranged in airflow communication with one of said at least one through-holes so as to be in airflow communication with the interior of one of said jacking-mattresses.
23. A pneumatic lift according to claim 22 comprising a plurality of longitudinal baffle panels.
24. A pneumatic lift according to claim 22 comprising a plurality of transverse baffle panels.
25. A pneumatic lift comprising:
- a plurality of jacking-mattresses stacked one atop another, each of said jacking-mattresses comprising; a top panel having a width, a length, a peripheral edge; a bottom panel having said width, said length, and a peripheral edge; a perimeter band extending between said top panel and said bottom panel such that said peripheral edges of said top and bottom panels are sealingly fastened to one another, said peripheral band defining at least one through-hole;
- a plurality of baffle-panels each having a width and a length and being attached to an inner surface of said top panel and an inner surface of said bottom panel so as to define air flow passageways;
- at least one valve sealingly positioned within said at least one through-hole so as to provide air flow access to said air flow passageways; and
- a source of pressurized air having a conduit suitable to be sequentially received in airflow communication with each of said at least one valves so as to be in sequential airflow communication with the interior of each of said jacking-mattresses.
26. A pneumatic lift according to claim 25 comprising a plurality of longitudinal baffle panels.
27. A pneumatic lift according to claim 25 comprising a plurality of transverse baffle panels.
28. A pneumatic lift comprising:
- a top jacking-mattress, a bottom jacking-mattress, and a plurality of intermediate jacking-mattresses stacked one atop another between said top jacking-mattress and said bottom jacking-mattress, wherein selected ones of said jacking-mattresses are arranged in internal air flow communication with one another, each of said jacking-mattresses includes; a top panel having a width, a length, and a peripheral edge, wherein selected ones of said intermediate jacking-mattresses comprise a top panel having at least one through-hole; a bottom panel having said width, said length, and a peripheral edge, wherein selected ones of said intermediate jacking-mattresses comprise a bottom panel having at least one through-hole; a perimeter band extending between said top panel and said bottom panel of each of said jacking-mattresses such that said peripheral edges of said top and bottom panels are sealingly fastened to one another;
- a plurality of baffle-panels each having a width and a length and being attached to an inner surface of said top panel and an inner surface of said bottom panel so as to be transversely oriented between said top panel and said bottom panel so as to define a pair of longitudinally extending air flow passageways disposed between an edge of said baffle-panels and an interior surface of said perimeter band; and
- a source of pressurized air arranged in airflow communication with the interior of at least one of said jacking-mattresses.
29. A transportable pneumatic lift comprising:
- at least three jacking-mattresses stacked one atop another wherein at least two of said jacking-mattresses are arranged in internal air flow communication with one another; and
- a sheet of Teflon releasably fastened to a bottom surface of a bottom most one of said at least three jacking mattresses.
30. A transportable pneumatic lift according to claim 29 wherein said sheet of Teflon is coextensive with said bottom most one of said at least three jacking mattresses.
31. A transportable pneumatic lift comprising:
- at least three jacking-mattresses stacked one atop another wherein at least two of said jacking-mattresses are arranged in internal air flow communication with one another; and
- a transfer mattress fastened to a bottom most one of said at least three jacking mattresses.
32. A transportable pneumatic lift according to claim 31 wherein said transfer mattress comprises a top sheet and a bottom sheet, that together define a plenum chamber with said bottom sheet being perforated with pinholes over at least a central surface area, said pinholes being in open flow communication with said plenum chamber so that when said transfer mattress is continuously charged with pressurized air, said air escapes through said pinholes so as to create an air bearing of relatively small height below an outer surface of said bottom sheet.
33. A transportable pneumatic lift comprising:
- a plurality of jacking-mattresses stacked one atop another wherein selected ones of said jacking-mattresses are arranged in internal air flow communication with one another; and
- a transfer mattress forming a bottom most jacking-mattress comprising; a top panel having a width, a length, and a peripheral edge; a bottom panel having said width, said length, and a peripheral edge and defining a plurality of pinholes in a central portion thereof; an outer perimeter band extending between said top panel and said bottom panel such that said peripheral edges of said top and bottom panels are sealingly fastened to one another; a plurality of baffle-panels being attached to an inner surface of said top panel and an inner surface of said bottom panel so as to be transversely oriented between said top panel and said bottom panel; an inner perimeter band extending between said top panel and said bottom panel and enclosing said plurality of baffle-panels so as to define an annular air flow passageway disposed between said outer perimeter band and said inner perimeter band and said baffle-panels thereby forming individual chambers between said baffles, said annular air flow passageway being in flow communication with said chambers; and a source of continuous pressurized air arranged in flow communication with said annular air flow passageway.
34. A transportable pneumatic lift according to claim 33 wherein said pinholes in said bottom panel only communicate with said individual chambers.
35. A transportable pneumatic lift according to claim 33 wherein said inner perimeter band is periodically perforated with through-holes so as to provide for air flow communication between said annular air flow passageway and said individual chambers.
36. A transportable pneumatic lift according to claim 33 wherein said baffle panels include through holes.
Type: Application
Filed: Dec 16, 2004
Publication Date: Jun 23, 2005
Inventor: David Davis (Bethlehem, PA)
Application Number: 11/013,761