Abstract:
A tool allowing both the inflation and deflation of air-filled bags such as dunnage bags is disclosed. The tool comprises a sliding control to easily and safely turn the flow of air on and off. The tool is switched from inflation to deflation mode by moving the bag connecting valve from one end of the device to the other.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application is a continuation-in-part of U.S. utility patent application Ser. No. 10/817, 356, filed on Apr. 2, 2004, and entitled “Inflation and Deflation Apparatus,” which in turn claimed priority from U.S. provisional patent application no. 60/511,047, filed on Oct. 14, 2003, and entitled “Inflation and Deflation Apparatus.” Both of these applications are incorporated wherein by reference. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     The present invention relates to an apparatus for the inflation and deflation of air-filled bags, such as the dunnage bags commonly used to cushion cargo loads in truck trailers, railroad cars, and the like.  
         [0003]     Inflatable dunnage bags are a common means of cushioning loads shipped via truck trailer, railroad car, or other typical shipping container, particularly where the cargo only partially fills the container and shifting during transport might cause damage. Typical dunnage bags in use today are constructed of one or more layers of paper surrounding a plastic lining. The paper serves to protect the bags from tearing, and thus a greater number of layers may be used in applications where the risk of damage to the dunnage bag is greater. A valve for filling the dunnage bag, usually constructed of plastic, is attached through a hole cut in the bag during manufacture. The bags are shipped flat from the manufacturer, and must be inflated by shipping personnel as containers are loaded with cargo.  
         [0004]     The tools currently in use to fill dunnage bags with air are often simply converted tire inflation tools, which are attached to a hose leading from a source of compressed air. Some specialized tools are available for dunnage bag deflation, such as taught by U.S. Pat. No. 5,437,301 to Ramsey. In the use of such devices, the bag is first placed in the space that it will occupy as cargo is loaded into a container, and the inflation device is attached to the bag valve. The bag is then filled with air. until an appropriate air pressure within the bag is achieved. The inflation tool may connect with the bag valve through a ball-lock quick-disconnect attachment, which may be engaged and disengaged by simply sliding a ring on the attachment point up or down. Filling is thus a relatively simple operation, requiring only a few seconds of the operator&#39;s time.  
         [0005]     A significant limitation of the current inflation tools is that they present no way to rapidly deflate a dunnage bag once the cargo is ready to be unloaded. The valve assembly in some such bags may be unscrewed to release air pressure within the bag, but because the bags are fairly rigid (owing to the protective paper covering) they tend not collapse simply due to the equalization of air pressure inside and outside of the bag. The bags cannot be quickly and conveniently reduced to a flat configuration such as they are shipped from the manufacturer. As a result, the standard industry practice is for shipping and receiving personnel to simply cut the bags with a utility knife in order to deflate them quickly for removal.  
         [0006]     Dunnage bags are not reusable once cut, and thus they are generally considered to be a one-use, disposable commodity. Significant cost savings could be realized by the reuse of these dunnage bags. This could be rendered practical by devising a means to rapidly and easily deflate a dunnage bag without damaging the dunnage bag. The bags must be restored to the flat shape they held prior to their original use, so that they can be easily and compactly stored.  
         [0007]     The prior art does include previous attempts to develop deflation tools for dunnage bags. U.S. Pat. No. 5,437,301 to Ramsey, discussed above, teaches a rotating valve actuator that selectively allows the flow of compressed air across an air passage connected to the dunnage bag in order to facilitate deflation. U.S. Pat. No. 6,053,222 to Peters teaches a dunnage bag deflation tool that uses a high-pressure air source to open the dunnage bag air valve, thereby allowing deflation, and also suck air out of the bag by discharging the air through a venturi tube. A venturi tube in its simplest form is an air passage with a region of restricted diameter. According to the Bernoulli inverse relationship between air velocity and pressure, passage of air through the restricted region of a venturi tube creates a low-pressure region. This low-pressure region results in a negative pressure or suction effect that may be used to draw air out of an attached container. Peters teaches two different embodiments of the deflation device, which differ by the means through which the device may be switched from inflation to deflation mode. One device calls for the operator to simply place a thumb over the venturi tube exit, thereby blocking that means of egress for the high-pressure air and directing the high-pressure air into the bag. The other embodiment incorporates a manually set bi-stable switch set at the entrance to the venturi tube, which prevents air from ever entering the venturi tube and thus forcing high-pressure air in the direction of the dunnage bag valve.  
         [0008]     U.S. Pat. No. 5,454,407 to Huza et al. teaches another apparatus to both inflate and deflate a dunnage bag. This device incorporates the venturi effect as part of an automatic pressure sensing system, but relies on hand pressure directly to the dunnage bag for deflation. Other devices to inflate and deflate different types of chambers are known in the art, such as that taught by U.S. Pat. No. 5,947,168 to Viard for inflation and deflation of an air mattress.  
         [0009]     Each of these devices suffers from important limitations. While the Peters device allows for the inflation and deflation of a dunnage bag using an integrated tool, its control mechanisms are of limited practicality. The operator of such a device should ideally be able to quickly turn on and off the source of high-pressure air, and quickly adjust the mode setting of the device to either inflate or deflate a dunnage bag. Ideally, the necessary controls would be simple and easily manipulated. The use of the operator&#39;s thumb to maintain the Peters device in the inflation mode would quickly result in operator fatigue. Given the large number of cargo containers that may be loaded and unloaded in a typical shipping facility during an operator&#39;s work shift, this rudimentary control mechanism would quickly prove unworkable. The use of a switch at the entrance of the venturi tube is an improvement, but because of its design and position on the device would be prone to failure. Furthermore, the overall design of the device lacks any means of dissipating or quieting the flow of high-pressure air out of the venturi tube during deflation of a dunnage bag; it would result in a violent burst of air moving directly toward the operator. This situation raises significant safety concerns. The air escaping in this manner would also create a great deal of noise, which may be not only uncomfortable for the operator but also may raise a safety issue itself. Finally, the design of the device does not incorporate any convenient means of holding the device during inflation and deflation; this is an important safety concern as well, since if the valve connection should fail then the device would be propelled backward at great speed due to force of air. In this situation, the device would likely swing in an arc due to the attached (but flexible) air hose, and could strike the operator or a bystander with great force, potentially causing severe injury or property damage.  
         [0010]     The limitations of the prior art are overcome by the present invention as described below.  
       BRIEF SUMMARY OF THE INVENTION  
       [0011]     The present invention comprises an inflation and deflation device with a control mechanism and operational features that make it convenient, practical, and safe for use by operating personnel. Switching of the device from an inflation to a deflation mode is achieved by merely switching the position of the dunnage valve bag connector fitting from one end of the device to the other. Air flow is turned on or off by sliding a control mechanism near the handle of the device, which provides a sure grip for the operator. This mechanism results is a simple and reliable means by which the operator may change the mode of operation of the device. Air exiting the device is muffled through the barrel and is directed away from the operator. This device both reduces the likelihood of injury to the operator due to a violent rush of air during deflation, and also dampens the noise created by air rushing out of the device during deflation.  
         [0012]     It is therefore an object of the present invention to provide for a single, integrated tool for the inflation and deflation of dunnage bags and like containers.  
         [0013]     It is a further object of the present invention to provide a device for the inflation and deflation of air-filled bags with a simple means for inflation/deflation selection and a simple means of turning on and off the flow of air to the device.  
         [0014]     It is also an object of the present invention to provide a device for the inflation and deflation of air-filled bags that disperses air ejected from the device during deflation mode away from the operator.  
         [0015]     It is also an object of the present invention to provide a device for the inflation and deflation of air-filled bags that improves on the safety of existing devices.  
         [0016]     It is also an object of the present invention to provide a device that reduces the noise created by the flow of air from the device during deflation mode.  
         [0017]     These and other features, objects and advantages of the present invention will become better understood from a consideration of the following detailed description of the preferred embodiments and appended claims in conjunction with the drawings as described following. 
     
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS  
       [0018]      FIG. 1  is a perspective view of a preferred embodiment of the present invention.  
         [0019]      FIG. 2  is an exploded perspective. view of a preferred embodiment of the present invention.  
         [0020]      FIG. 3  is a partial cut-away elevational view of a preferred embodiment of the present invention in the “inflation” configuration.  
         [0021]      FIG. 4  is a cut-away view of the preferred embodiment of the present invention in the “deflation” configuration.  
         [0022]      FIG. 5  is a detail cut-away view of a preferred embodiment of the present invention in the “on” configuration.  
         [0023]      FIG. 6  is a detail cut-away view of a preferred embodiment of the present invention in the “off” configuration. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0024]     Referring to  FIGS. 1 and 2 , the major components of a preferred embodiment of the present invention may now be described. Inflation barrel  10  comprises a tube with an open bore. Removably attached to inflation barrel  10  in the “inflation” configuration, as depicted in  FIGS. 1 and 2 , is valve connector assembly  12 . Valve connector assembly  12  is fashioned so as to provide a selectively lockable and unlockable engagement with a dunnage bag inflation valve (not shown). The valve connector assembly  12  may preferably be constructed as a ball-lock quick-disconnect valve connector as described in U.S. Pat. No. 5,437,301 to Ramsey, which is incorporated herein by reference. o-rings  14  is seated within an annular groove on the interior of inflation barrel  10 , thereby providing an airtight seal between inflation barrel  10  and valve connector assembly  12 . In the preferred embodiment, valve assembly  12  is held in place by set screw  16 . Set screw  16  extends through a hole in the side of inflation barrel  10  and part-way into the interior of inflation barrel  10 . As valve connector assembly  12  is inserted into inflation barrel  10 , a notch in the interior end of valve connector assembly  12  must be aligned with set screw  12  in order for valve connector assembly  12  to be fully seated. Once engaged, valve connector assembly  12  may be turned with respect to inflation barrel  10 , whereby set screw  16  extends into the groove near the end of that portion of valve assembly  12  that extends within inflation barrel  10 . Valve assembly  12  may not be removed until it is again turned with respect to inflation barrel  10  such that the notch of valve assembly  12  and set screw  16  are aligned.  
         [0025]     Body  18  is of a generally annular shape, and receives inflation barrel  10  through its interior, holding inflation barrel  10  in place by means of set screws  22 . In the preferred embodiment, inflation barrel  10  extends completely through body  18  and extends slightly from the opposite side of body  18 . Attached to body  18  by means of screws  24  is handle  20 . Handle  20  is hollow to allow air flow, as will be explained following, but is preferably of an ergonomic shape on its exterior. The purpose of handle  20  is to allow the operator to maintain a firm grip on the device during use, and thus cross-hatching or other means may preferably be used to improve the ability of a user to grip the device at handle  20 . At its distal end, handle  20  includes female threads to receive air passage  26 . Air passage  26 , preferably constructed of steel or brass for strength, controls the passage of air from an air hose (not shown) into the device. Air passage  26  comprises two rows of air holes  28  passing through the walls of air passage  26 , and a barrier (not shown in  FIG. 1  but illustrated in  FIGS. 5 and 6  as will be described below) that blocks the passage of air through air passage  26  between the rows of air holes  28 . In the preferred embodiment, the barrier is formed of a single piece of metal as air passage  26 ; the barrier is formed by machining the hollow center of air passage  26  using two bores drilled toward each other but not quite meeting in the middle of air passage  26 .  
         [0026]     Fitted slideably over air passage  26  is annular slide  30 . Slide  30  comprises slots on its interior to receive two o-rings  32 , one positioned towards each end of slide  30 . Slide  30  has freedom of movement in a longitudinal direction with respect to air passage  26 . In the preferred embodiment, slide  30 &#39;s longitudinal movement is blocked near the distal end of air passage  26  by a flared end designed to receive a standard wrench, and blocked near the proximal end of air passage  26  by a keeper  34 , which is fitted into a slot sized to receive it on the exterior of air passage  26 . Fitted into the female threads at the distal end of air passage  26  is air fitting  36 , which is designed to receive a hose fitting of the standard quick-disconnect type as commonly employed for equipment supplying pressurized air.  
         [0027]     Again referring to  FIG. 2 , fitted annularly within the bore of inflation barrel  10  is air distributor  38 . Distributor o-rings  40  are placed neither either end of distributor  38  to block the flow of air around either end of distributor  38  at the inner wall of the bore of inflation barrel  10 . Distributor  38  further comprises a number of distributor inlets (not shown); the preferred embodiment comprises six distributor inlets, but alternative embodiments may include any number of such inlets. The distributor inlets are preferably located at the edge of the base of the truncated cone formed by the inner portion of distributor  38 . As will be explained more fully below, air may pass through inflation barrel  10  through the inlets of distributor  38  and thereby pass through the device.  
         [0028]     Deflation barrel fitting  42  is threaded into inflation barrel  10  at the end extending slightly from body  18 . Deflation barrel fitting  42  comprises a hollow air passage that gradually widens as it extends away from body  18 . Deflation barrel fitting  42  achieves an air-tight fit with inflation barrel  10  because it sits against the o-ring  40  that is fitted at the adjacent end of distributor  38  o-ring  46  is fitted at the other end of deflation barrel fitting  42 , at the point where deflation barrel  44  threadably fits onto deflation barrel fitting  42 . Thus an air-tight fit is achieved at each end of deflation barrel fitting  42 . Like deflation barrel fitting  42 , deflation barrel  44  comprises a hollow air passage at its interior. This passage, however, is wider and straight-sided in that portion of deflation barrel  44  furthest from deflation barrel fitting  42 , but is sized down at the opposite end and shaped to receive valve  48 . Valve  48  is capable of sliding over a short distance within deflation barrel  44 , for reasons as will be explained in the discussion of the operation of the device following. A set screw  16  extends transversely through deflation barrel  44  near its distal end, in a position congruent with that of the set screw  16  fitted into inflation barrel  10 , and similarly an o-ring  14  is fitted in a groove at the interior and near the distal end of deflation barrel  44 , in order to provide an air-tight fit with bag valve connector assembly  12  When the device is operated in deflation mode.  
         [0029]     The principal components of the device, including inflation barrel  10 , body  18 , handle  20 , deflation barrel fitting  42 , and deflation barrel  44  may be formed of any sufficiently strong, rigid material, the stronger plastics being the preferred material due to their light weight and relatively low manufacturing cost. Likewise, distributor  38  and valve  48  may also be constructed of strong, lightweight materials such as plastics. For purposes of strength, aluminum, brass or other metals are used in the preferred embodiment for the construction of air passage  26  and slide  30 . The various o-rings in the preferred embodiment are of the types commonly found commercially, constructed of rubber or a like resilient material.  
         [0030]     Referring now to  FIGS. 5 and 6 , the method of turning a preferred embodiment of the present invention “on” and “off” (that is, allowing the flow of compressed air through the device or stopping the flow of compressed air through the device) may be described.  FIG. 5  depicts the device in the “on” position, with the arrows indicating the path of air flow through the device, and  FIG. 6  depicts the device in the “off” position. It may be seen that sliding slide  30  towards the distal end of air passage  26  causes the flow of air to be interrupted. Since the inner hollow section of air passage  26  does not pass completely through air passage  26 , air must flow out through one row of air holes  28  and then back in through the other row of air holes  28  in order to reach the proximal end of air passage  26 . As shown in  FIG. 6 , the distal row of air passages  28  are cut off from the proximal row of air holes  28  by slide  30  and associated o-rings  32 . In  FIG. 5 , however, when slide  30  is in the “open” position, air may flow into air passage  26 , out through the distal row of air holes  28 , into the cavity formed by the space between the outer surface of air passage  26  and the inner surface of slide  30 , then back into air passage  26  through the lower row of air holes  28 . From this point, the air may flow into handle  20  and on through the device. As previously discussed, the travel of slide  30  is limited by air passage  26  at its distal end and by keeper  34  at the proximal end of air passage  26 .  
         [0031]     Referring now to  FIGS. 3 and 4 , the method of operating the preferred embodiment of the invention in inflation mode and deflation mode may now be described. The device is shown in inflation mode in  FIG. 3 . Bag valve connector assembly  12  is fitted at the end of inflation barrel  10 , held in place by set screw  16 . Air flows from air passage  26  as described above, entering handle  20 . Air then flows through an opening in body  18 , through a matching opening in inflation barrel  10 , and into a cavity between the outer surface of distributor  38  and the hollow interior of inflation barrel  10 . The inlets of distributor  38  allow air to pass through distributor  38 , into inflation barrel  10 , and then into bag valve connector assembly  12 . Air may then pass into the bag to be filled from that point when the bag valve is connected to the device. Air pressure formed within deflation barrel fitting  42  forces valve  48  to move away from body  18 , thereby closing and sealing the opening through deflation barrel  44 .  
         [0032]      FIG. 4  depicts the preferred embodiment of the invention in deflation mode. In this mode, bag valve connector assembly  12  is fitted not to inflation barrel  10 , but to deflation barrel  44 . Again, bag valve connector assembly  12  is preferably held in place by a set screw  16 . Air flows from air passage  26  as described above entering handle  20 . Air then flows through an opening in body  18 , through a matching opening in inflation barrel  10 , and into a cavity between the outer surface of distributor  38  and the hollow interior of inflation barrel  10 . The inlets of distributor  38  allow air to pass through distributor  38 , into inflation barrel  10 , and then exit the device. The length of inflation barrel  10  serves to muffle the sound of air exiting the device, and also directs the air away from the operator to avoid injury.  
         [0033]     Air is drawn from the dunnage bag through bag valve connector assembly  12  and into deflation barrel  44  because the insertion of bag valve connector assembly  12  forces valve  48  into the open position. As illustrated in  FIG. 4 , the end of bag valve connector assembly  12  pushed against the distal end of valve  48 , forcing it toward body  18 . This prevents the closure of valve  48  due to air pressure within deflation barrel fitting  42 . Furthermore, air is drawn from the dunnage bag, by way of bag valve connector assembly  12 , deflation barrel  44 , and deflation barrel fitting  42 , due to the venturi effect created by distributor  38 . As may be noted in  FIG. 4 , distributor  38  includes a cone-shaped section that functions according to the well-known Bernoulli principle, creating a negative air pressure in the region behind distributor  38 . Thus the device creates a suction that draws air from the dunnage bag, along with the pressurized air entering the device at air fitting  36 , through inflation barrel  10  and out of the device. Using typical compressed-air sources such as industrial-sized air compressors, the preferred embodiment of the device is capable of reducing a standard-sized dunnage bag to a flat shape appropriate for storage and reuse in only a few seconds.  
         [0034]     The present invention has been described with reference to certain preferred and alternative embodiments that are intended to be exemplary only and not limiting to the full scope of the present invention as set forth in the appended claims.