Inflator/deflator accessory for air compressor

An accessory for inflating and deflating inflatable articles comprises a conduit 13, an intake 17, an outtake 19 and an injector 35. In use, conduit 13 functions as a venturi tube for rapid inflation and deflation of inflatable articles, preferably, articles having a large, low pressure air volume. For inflation, outtake 19 is connected to the inflatable article. For deflation, intake 17 is connected to the inflated article. For inflation and deflation, a source of pressurized air, preferably, an electric air compressor is connected to injector 35.

FIELD OF THE INVENTION 
This invention relates to a device for inflating and deflating low pressure 
inflatable articles and a method for using the device for inflation and 
deflation of such articles. More particularly, the device is intended for 
use with a source of pressurized air such as an electric air compressor to 
increase the airflow for rapid inflation and deflation of an article. 
BACKGROUND OF THE INVENTION 
Electric air compressors are commonly used to inflate a wide range of 
consumer articles such as tires, air mattresses, rafts, swimming pools and 
balls. The suitability of an air compressor for such applications is 
determined primarily by two criteria, the airflow rate and the maximum 
pressure developed by the compressor. These criteria determine whether the 
compressor is capable of inflating the article to the desired pressure and 
the length of time required to inflate the article to the desired 
pressure. Consumer air compressors cannot be cost effectively designed to 
rapidly inflate articles having a wide range of air volumes and internal 
air pressures. Therefore, the design of consumer air compressors must be a 
compromise. 
One application for which most consumer air compressors do not provide 
efficient inflation is articles having a large air volume and a relatively 
low air pressure such as air mattresses. For example, an air mattress 
which is 58".times.77".times.8" in size has an air volume of approximately 
21 cubic feet at 0.1 psig. air pressure. To inflate such a mattress with 
one commercially available air compressor, which is rated at 1.0 cubic 
feet per minute (cfm) at 30 pounds per square inch (psi), approximately 
16.5 minutes are required. It would, of course, be desirable to provide a 
low cost accessory for a compressor for reducing the inflation time. 
In addition to time consuming inflation, another problem arising from the 
use of high air volume, low pressure inflatable articles is that there is 
no efficient means of deflating the article for storage or transport. Thus 
it would be desirable to provide a low cost accessory for a compressor for 
rapidly deflating an article. 
Accordingly, the primary object of this invention is to provide an 
accessory for a pressurized air source, (preferably, an air compressor) 
for inflating and deflating high volume, low pressure articles and a 
method for using the accessory for inflating and deflating such articles. 
Still another object is to provide an accessory which is rapidly and 
easily convertable between an accessory for inflating an article and an 
accessory for deflating an article. 
SUMMARY OF THE INVENTION 
In accordance with one aspect of the invention, as embodied and described 
herein, a device for inflating and deflating inflatable articles comprises 
a conduit having a sidewall, an intake and an outtake. A tubular injector 
is fixed to and extends through the sidewall. The injector has an opening 
external to the sidewall which is connectable to a source of pressurized 
air and has a small orifice within the conduit for expelling a small 
volume, high velocity, low pressure air stream. An air inlet is provided 
in the sidewall. A closure or the inlet is movable between an open 
position for permitting airflow through the inlet and a closed position 
for preventing airflow through the inlet. 
The conduit operates as a venturi tube. For inflation of an article, the 
outtake is connected to the article and air is drawn in through the inlet 
and the intake. The provision of an air inlet in addition to an air 
intake, provides enhanced airflow for more rapid inflation. For deflation, 
the air inlet is closed and the intake is connected to the inflated 
article to be deflated. Rapid and complete deflation of the article may be 
achieved in this manner. 
The closure preferably comprises a first section of the conduit and a 
second section of the conduit coaxially overlapping the first section and 
rotatable relative to the first section for opening and closing the inlet. 
To guide the relative rotation, a tongue and groove connection is 
preferably provided between the sections. The tongue and groove connection 
may also incorporate a stop for limiting relative rotation to define open 
and closed positions of the closure. 
To adapt the size of the outtake of the conduit to fit in inflatable 
articles for a variety of sizes of fill valves, an adapter nozzle, which 
terminates in an appropriate size to fit the fill valve, may be connected 
to the outtake. 
In accordance with another aspect of the invention, the closure serves as a 
means for adjusting the size of the intake to convert the device back and 
forth between inflation an deflation modes. In one embodiment, the closure 
means is constituted by first and second sections of the conduit which are 
relatively rotatable to adjust the size of the intake. In an alternate 
embodiment, the closure means is constituted by first and second sections 
of the conduit which are detachably connectable to adjust the size of the 
intake. 
In accordance with another aspect of the invention, the method for using 
the device described above for inflation comprises three primary steps. 
The first step is to connect the outtake of the conduit to a fill valve of 
the article. The second step is to generate a small volume, high velocity, 
low pressure air stream from the orifice of the injector toward the 
outtake. The third step is to generate a high volume, low pressure air 
stream which is taken in through the intake and inlet, is transmitted 
through the passageway of the conduit and is expelled into the article 
from the outtake. If the intake is not initially opened, the closure for 
the inlet is moved to an open position. In this manner, rapid inflation of 
the article may be achieved. Incoming air for inflating the article is 
sourced from the injector, the intake and the inlet. The provision of the 
inlet provides greatly enhanced airflow to reduce inflation time. 
To increase the maximum pressure to which the article may be inflated, the 
intake and the inlet may be closed to increase the pressure within the 
conduit. With the intake and inlet closed, the article is now inflated 
through air sourced only from the injector. Preferably the inlet is closed 
by relatively rotating the first and second sections of the conduit to 
misalign the apertures in the sections. The intake is preferably closed by 
covering it with a finger. 
In accordance with another aspect of the invention, the method for 
deflating the article comprises four primary steps. The first step is to 
connect the intake to the fill valve of the article. The second step is to 
close the air inlet. The third step is to generate a small volume, high 
velocity, low pressure air stream from the orifice toward the outtake. The 
fourth step is to generate a high volume, low pressure air stream which is 
expelled from the article through the intake, is transmitted through the 
passageway and is expelled from the outtake into the article. 
The intake is preferably connected to the fill valve of the article by 
inserting an adapter nozzle over the intake and inserting the nozzle into 
the fill valve of the article. 
As will be appreciated, the device may be conveniently used for inflation 
or deflation of an article and may be readily converted between inflating 
and deflating applications. More rapid inflation may be achieve by 
sourcing the incoming air from both the air inlet and the intake. Rapid 
and complete deflation may be achieved by simply interchanging the 
connection of the fill valve of the article between the outtake and the 
intake, and closing the air inlet. Accordingly, the invention provides a 
simple low cost accessory which enables consumer air compressors to be 
used for inflation and deflation of high volume, low pressure inflatable 
articles which is an application for which most consumer electric air 
compressors are not well suited. 
Additional objects and advantages of the invention will be apparent from 
the detail description of the embodiments, the appended claims and the 
accompanying drawings or may be learned by practice of the invention.

DESCRIPTION OF EMBODIMENTS 
I. Device for Inflation and Deflation 
The preferred embodiment of a device 11 for inflating and deflating 
articles is shown in FIGS. 1 and 2. Details of the embodiment are shown in 
FIGS. 3-8. An alternate embodiment of a device 111 is shown in FIGS. 9, 
10. In brief, device 11 comprises a conduit 13, an intake 17, an outtake 
19 and an injector 35. In use, conduit 13 functions as a venturi tube for 
rapid inflation and deflation of inflatable articles, preferably, articles 
having a large volume, low pressure, air volume. For inflation, outtake 19 
is connected to the inflatable article. For deflation, intake 17 is 
connected to the inflated article. For inflation and deflation, a source 
of pressurized air (not shown) is connected to injector 35. 
In accordance with the invention, as depicted in FIGS. 1, 2, device 11 
comprises conduit 13 having a sidewall 15, intake 17 and outtake 19. As 
embodied herein, conduit 13 includes a pair of halves 21, 23 joined along 
line 25 by a plurality of pins extending from half 23 and fitting into 
cavities 27 in half 21. Halves 23, 25 are also held together by a sleeve 
29 fitted over the intake end of conduit 13 and by sleeve 31 fitted over 
the outtake end of conduit 13. 
Preferably, conduit 13 is elongated and has a central passageway 33 
extending between intake 17 and outtake 19 which are located at opposed 
ends of passageway 33. 
In accordance with the invention, device 11 further comprises tubular 
injector 35 fixed to and extending through sidewall 15. Injector 35 has an 
opening 37, which is external to sidewall 15 and is connectable to a 
source of pressurized air (not shown), and has a small orifice 39 within 
conduit 13 for expelling a small volume, high velocity, low pressure air 
stream 41. As embodied herein an injector 35 is sized to be connectable to 
connectors such as a universal clamp valve and a chuck valve which are 
commonly used on electric air compressors and hand operated pumps. 
Alternatively, the outer periphery of injector 35 may be threaded for 
connection of an air source having a threaded connector. Pressurized air 
preferably from an electric compressor is blown through opening 37 and is 
confined in cavity 43 of injector 35 to build up a small volume of 
pressurized air. The air is then expelled through orifice 39 as a small 
volume, high velocity, low pressure air stream 41. The pressure of air 
stream 41 is equal to the pressure within passageway 33. Orifice 39 is 
located within passageway 33 coaxially of longitudinal axis 48 (FIG. 2) 
and is directed toward outtake 19 to generate a high volume, low pressure 
air stream 45 through outtake 19. A venturi throat 44 is formed at the 
junction of outtake 19 and frustroconical section 46. In accordance with 
the well known operation of a venturi tube, the diameter of orifice 39 is 
determined by the airflow rate of the source of pressurized air and by the 
distance (along axis 48) between venturi throat 44 and orifice 39. The 
airflow rate of air stream 45 is optimized if the velocity of air stream 
41 is approximately equal to sonic velocity. Air stream 45 may be used for 
inflation or deflation of an article depending on the source from which 
the stream 45 is drawn in addition to stream 41. 
In accordance with the invention, as shown best in FIGS. 2, 4, 5 device 11 
further comprises an air inlet 47 in sidewall 15 and a closure means 49 
for inlet 47 movable between an opened position for permitting airflow 
through the inlet and a closed position for preventing airflow through the 
inlet. As embodied herein, closure means 49 preferably comprises a first 
section 51 of conduit 13 and a second section 53 of conduit 13 which 
coaxially overlaps first section 51 and is rotatable relative to first 
section 51 for opening and closing air inlet 47. Air inlet 47 preferably 
comprises a plurality of apertures 55 in section 51 and a plurality of 
apertures 57 in section 53. The number of apertures constituting inlet 47 
is a matter of choice. Although it is preferred to have a separate inlet 
47, as will be explained in connection with the second embodiment shown in 
FIGS. 9 and 10, inlet 47 and intake 17 may be combined into a single air 
intake and also considered to be a single air intake in the preferred 
embodiment. To optimize airflow through passageway 33, the open area of 
aligned apertures 55, 57 and inlet 17 should be approximately equal to the 
interior transverse cross-sectional area of passageway 33 adjacent to and 
upstream of injector 35 (i.e., the internal area of section 51 in the 
region of line 4--4). 
As will be appreciated, closure means 49 may be configured in a variety of 
different ways. For example, air inlet 47 may be constituted by one or 
more fixed openings which are closable by a plug or cap closure. In the 
preferred embodiment when intake 17 and inlet 47 are considered in 
combination as an intake for conduit 13, closure 49 constitutes a means 
for adjusting the size of the intake opening to convert device 11 back and 
forth between inflation and deflation modes which are described in more 
detail below, particularly in Sections II and III. 
To guide the relative rotation of sections 51, 53, a tongue 59 and groove 
61 connection is preferably formed between sections 51, 53. To limit the 
relative rotation between first and second sections 51, 53 device 11 
further comprises a stop 63 (FIG. 4). Stop 63 preferably comprises 
recesses 64, 65 formed in one of the first and second sections 51, 53 and 
projections 66, 67 fixed to the other of the first and second sections and 
slidably mounted, respectively, in the recesses 64, 65. Preferably 
recesses 64, 65 are formed in tongue 59 extending from first section 51 
and projections 66, 67 extend from groove 61 formed in second section 53. 
Projections 66, 67 ride in recesses 64, 65 and limit the relative rotation 
of sections 51, 53 by engagement with the end walls 68-71 of recesses 64, 
65 to define the open and closed positions of closure 49. The opened 
position is shown in FIG. 4 in which projections 66, 67 engage end walls 
69, 71. In the closed position, projections 66, 67 engage end wall 68, 70. 
Two projections 66, 67 and recesses 64, 65 are preferred, however, one 
projection and recess may be used. As will be appreciated, the tongue and 
groove connection 59, 61 serves the dual purposes of guiding relative 
rotation between sections 51, 53 and also limiting the relative rotation 
to define the open and closed positions of air inlet 47. 
Inlet 47 is used during inflation of an article to provide a source of 
incoming air in addition to air from intake 17. As a result, a 
significantly higher level of airflow may be achieved for inflation 
resulting in more rapid inflation of low pressure, inflatable articles. 
For rapid deflation of an article, inlet 47 is closed so that the entire 
source of air to support air stream 45 is from intake 17. As will be 
appreciated, device 11 is rapidly and easily converted between inflation 
and deflation modes merely by opening or closing inlet 47. 
As shown in FIG. 6 to inflate an article 73 (e.g., an air mattress) outtake 
19 may be directly inserted into a fill valve 75 of article 73 until a 
generally air tight seal is formed between wall 79 and the outer profile 
of conduit 13. To provide an outer profile conducive to forming a seal, as 
seen in FIGS. 1 and 2, conduit 13 has a cylindrical outer wall forming 
outtake 19 and has frustroconical section 46 which increases in diameter 
toward injector 35. 
To permit outtake 19 to fit within fill valves having a wide range of inner 
diameters, one of a plurality of adapter nozzles (not shown) may 
alternatively be connected to outtake 19. An exemplary adapter nozzle 81 
is illustrated in FIG. 7. Nozzle 81 is preferably connected to outtake 19 
by a snap fit formed by rib 83 and groove 85. To permit attachment and 
removal of nozzle 81, axially extending slots 87 (only one shown) are cut 
in the sidewall of nozzle 81 so that rib 83 may slide into and out of 
groove 85. Nozzle 81 terminates in an end smaller in outer diameter than 
the outer diameter of outtake 19 and is thus intended to fit into fill 
valves smaller than that depicted in FIG. 6. Nozzle 81 has been found to 
be particularly suitable for use with a fill valve (not shown) having a 
flap closure which must be pivoted away from the valve opening for 
inflation and deflation of the article. 
A larger diameter adapter nozzle has a greater airflow than a smaller 
diameter adaptor nozzle. But, airflow in a large nozzle drops as pressure 
increases within the inflatable article more than a smaller diameter 
adapter nozzle. The preferred inner diameter of outtake 19 is 0.60 inches. 
Exemplary adapter nozzle inner diameters are 0.45 inches and 0.28 inches. 
The performance enhancement obtained through air inlet 47 is greater for 
larger outtake diameters. Significant performance enhancement is obtained 
for the 0.60 inch diameter outtake and for the 0.45 inch diameter adapter 
nozzle. For the 0.28 inch adapter nozzle, air inlet 47 does not provide an 
increased airflow. 
For deflation, one of the plurality of adapter nozzles (not shown) of which 
nozzle 81 is representative is connected to intake 17 by a snap fit formed 
by rib 83 and groove 91 connection identical to the connection between 
nozzle 81 and outtake 19. Because the irregular outer profile of apertures 
57 prevents a good seal from being formed between intake 17 and a fill 
valve, an adapter nozzle is always connected to intake 17 for deflation of 
an article. Nozzle 81 is fitted in the fill valve of the article to be 
deflated and a high volume, low pressure air stream is expelled from the 
article through the intake 17, is transmitted through passageway 33 and is 
expelled from outtake 19 as will be explained in more detail below. 
An alternate embodiment of a device 111 for inflating and deflating 
articles in accordance with the invention is shown in FIGS. 9 and 10. In 
brief, device 111 comprises a conduit 113, an injector 115 and a closure 
means 117. Conduit 113 comprises a sidewall 119 defining a passageway 121, 
an intake 123 and an outtake 125. As embodied herein, a first section 127 
terminates in an end 129 defining an intake 131 for inflation. A second 
section 133 of conduit 113 terminates in an end 135 defining an intake 137 
for deflation. As shown in FIGS. 9, 10, sections 127, 133 are detachably 
connected together by an annular bead 139 on section 127 which snap fits 
into a mating annular groove 141 in section 133. Slots 143 may be formed 
in sidewall 119 of section 133 to permit the sidewall 119 of section 133 
to flex when attaching to and detaching from section 127. 
Injector 115 is preferably constructed identically to injector 35 shown in 
FIG. 2 and includes an external opening 145 and an orifice 147 for 
expelling an air stream 149. 
Closure means 117 is an alternate embodiment of closure means 49 (FIG. 2) 
and is for adjusting the size of the intake 123 to convert device 111 back 
and forth between inflation and deflation modes. As embodied herein, 
closure means 117 is constituted by conduit section 133. Intake 123 is 
adjusted for inflation by detaching section 133 to expose inflation intake 
131. Only section 127 is used for inflation of an article. Intake 123 is 
adjusted for deflation by attaching first and second sections 127, 133 
together which covers inflation intake 131 and assembles deflation intake 
137 in an operative condition. Intake 123 is adjustable between the sizes 
of intakes 131, 137 and thus is adjustable between a total open surface 
area approximately equal to the transverse cross-sectional area of 
passageway 121 adjacent to an upstream of orifice 147 and a total open 
surface area approximately equal to the area of the opening in the fill 
valve of an article to be deflated such as article 73 in FIG. 6. 
As will be appreciated, the embodiment of FIGS. 9, 10 illustrates an 
embodiment of the invention in which a separate air inlet (comparable to 
inlet 47 of the preferred embodiment) is not provided and is replaced by 
separate intakes 131, 137 for inflation and deflation respectively. 
II. Method for Inflation 
The method for using device 11 to inflate a low pressure inflatable article 
is another important aspect of the invention. According to this aspect of 
the invention, as illustrated in FIG. 6, the method comprises a first step 
of connecting outtake 19 to a fill valve 75 of article 73. As embodied 
herein, article 73 may be, for example, an air mattress with a 
conventional fill valve 75. Outtake 19 may be directly inserted into valve 
75. Or alternatively if outtake 19 has a larger diameter than the inner 
diameter of valve wall 79, then an adapter nozzle of an appropriate size 
may be fitted over outtake 19 so that a frictional air seal is provided 
between the outer surface of the adapter nozzle and the inner surface of 
wall 79. An exemplary adapter nozzle 81 is illustrated in FIG. 7. 
A second step is to generate a small volume, high velocity, low pressure 
air stream 41 from orifice 39 toward outtake 19. As embodied herein, to 
generate air stream 41, a source of pressurized air (not shown) is 
connected to opening 37 of injector 35 using a conventional connector 
supplied with the air source. The pressurized air source may be a 
conventional hand pump or is preferably an electrical air compressor such 
as the model 9527 Air Station.RTM. inflator manufactured by Black & Decker 
(U.S.) Inc. which provides 1.0 cubic feet per minute of air at 30 pounds 
per square inch. When the compressor is connected to injector 35, a small 
volume of high pressure air is built up within cavity 43 and is expelled 
through orifice 39 toward outtake 19 as a small volume, high velocity, low 
pressure air stream 41. 
A third step is to generate a high volume, low pressure air stream 45 which 
is taken in through intake 17 and inlet 47, is transmitted through the 
passageway 33 and is expelled into article 73 through outtake 19. As is 
well known in the operation of a venturi tube, the rapid increase in 
velocity of air stream 41 as it is expelled from orifice 39 causes 
acceleration of the air in passageway 33 to generate air stream 45. 
To achieve a high volume airflow for rapid inflation of an article, air 
inlet 47 is opened by relative rotation of the first and second sections 
51, 53 to align apertures 55, 57. Rotation of the first and second 
sections 51, 53 is guided by tongue 59 and groove 61 (FIGS. 2, 4). The 
open condition of closure 49 of air inlet 47 is shown in FIG. 4 and is 
defined by the engagement of projections 66, 67 with end walls 69, 71 of 
recesses 64, 65. 
To increase the maximum pressure to which article 73 may be inflated intake 
17 and air inlet 47 may be closed to increase the pressure within conduit 
13. Using a 1 cfm at 30 psi air source for injector 11, article 73 may be 
inflated to approximately 0.1 psig. with the air inlet 47 and intake 17 in 
an open condition. By closing air inlet 47 and intake 17, article 73 may 
be inflated to approximately 5 psig. Air inlet 47 is closed by relative 
rotation of first and second sections 51, 53 to misalign apertures 55, 57. 
Intake 17 is preferably closed by covering the intake with the operator's 
finger. Alternatively, intake 17 may be closed by inserting a cap (not 
shown) over the intake. 
Device 111 may be used to inflate a low pressure article by use of a method 
similar to that used for device 11. In the method, sections 127, 133 are 
detached; outtake 125 is connected to an article to be inflated; and an 
airstream 151 which is taken in through intake 131, is generated by 
airstream 149 to inflate the article. 
III. Method for Deflation 
The method for using device 11 to deflate a low pressure article forms 
another important aspect of the invention. According to this aspect, the 
method comprises the first step of connecting intake 17 to fill valve 75 
of article 73. As embodied herein, adapter nozzle 81 is connected to 
intake 17 as depicted in FIG. 8 through a snap fit of rib 83 in groove 91. 
Nozzle 81 is then inserted into fill valve 75 of articles 73 to establish 
an air seal between nozzle 81 and the inner surface of wall 79 of valve 
75. Alternatively, intake 17 may be configured so as to be directly 
insertable into valve 75 if desired. 
A second step is to close air inlet 47. As explained above, air inlet 47 is 
closed by operation of closure 49 which as embodied herein is closed by 
relative rotation of first and second sections 51, 53 to misalign 
apertures 55, 57. When apertures 55, 57 are misaligned, projections 66, 67 
are in engagement with recess end walls 68, 70. Closing inlet 47 converts 
device 11 from an inflator to a deflator and reduces the total opened area 
of conduit 13 upstream of orifice 39 from being approximately equal to the 
transverse cross-sectional area of passageway 33 adjacent to and upstream 
from injector 35 to approximately equal to the area of the opening in the 
fill valve of the article to be deflated. When inlet 47 is closed, only 
intake 17 is open. As discussed above for deflation, a properly sized 
adaptor nozzle 81 is preferably connected to intake 17 for deflation. 
A third step is to generate a small volume, low pressure, high velocity air 
stream 41 from orifice 39 toward outtake 19. As embodied herein, air 
stream 41 is preferably generated in an identical manner to the method for 
inflating article 73 as explained above. 
A fourth step is to generate a high volume, low pressure air stream which 
is expelled from article 73 through intake 17, is transmitted through 
passageway 33 and is expelled from outtake 19. As embodied herein, air 
stream 45 is generated in an identical manner to the generation of air 
stream 45 when inflating article 73 except that air stream 45 consists of 
air from air stream 41 and from intake 17 and thus does not include any 
air taken in from inlet 47 which is closed. Because the airflow through 
the passageway is more restricted during deflation than inflation, the 
rate for deflation is less than the rate for inflation. Thus, the 
deflation time is greater than the inflation time for the same article and 
the same pressurized air source. 
Device 111 may be used to deflate an article by a method similar to that 
used with device 11. In the method, sections 127, 133 are attached 
together; deflation intake 137 is connected to the fill valve of an 
article to be deflated; an airstream 149 is generated by connection of an 
air source to injector 115; and an airstream 151, which is expelled from 
the article to be deflated through intake 137, is generated by airstream 
149 and is expelled from outtake 125. 
IV. Performance of Device 
To illustrate the performance of the invention which has been optimized for 
use with a model 9527 Air Station Inflator.RTM. manufactured by Black & 
Decker (U.S.) Inc. which provides 1.0 cubic feet per minute of airflow at 
30 pounds per square inch, a prototype of device 11 was constructed as 
follows: inner diameter of outtake 19--0.60 inches, diameter of orifice 
39--0.040 inches and the distance between orifice 39 and throat 44--1.62 
inches. The prototype tested was functionally the same as the preferred 
embodiment depicted in FIGS. 1, 2 herein except that the air inlet in the 
prototype was constituted by a single large aperture. The following 
measurements were taken with the prototype for inflation and deflation of 
an air mattress (58 inches.times.77 inches.times.8 inches). 
______________________________________ 
Inflation/ Average 
Deflation Time 
Airflow 
Device Condition (Min:Sec) (cfm) 
______________________________________ 
Inflation w/inlet 47 open 
1:38 12.7 
Inflation w/inlet 47 closed 
2:00 10.3 
Deflation w/inlet 47 closed 
2:12 9.4 
______________________________________ 
As observed from the test, the inflation time is reduced by approximately 
18.5% by having inlet 47 open. Also, rapid and complete deflation of the 
mattress was obtained. 
It will be apparent to those skilled in the art that various modifications 
and variations can be made in the method and device of the invention 
without departing from the scope or spirit of the invention. Thus, it is 
intended that the present invention cover these modifications and 
variations provided they come within scope of the appended claims and 
their equivalents.