Abstrict A hydrogen peroxide vapor generation unit (10) receives hydrogen
peroxide and water solution at an interface (20) and interconnects
with an air dryer (14) by way of nipples (72 92). In one embodiment,
the dryer includes a clamping assembly (42) which is latched (74
94) with the nipples and which receives a disposable desiccant cartridge
(40). In an alternate embodiment, a reusable desiccant cartridge
(40') is connected directly to the nipples (72 92). When the desiccant
cartridge (40') is saturated, it is removed and placed in a regenerator
unit (120). A regenerated cartridge is installed in its place.
Claims Having thus described the preferred embodiment, the invention is
now claimed to be:
1. A peroxy vapor system including: a liquid peroxy solution interface
for receiving a source of liquid peroxy solution; a vaporizer for
vaporizing the liquid peroxy solution and entraining the vapor in
air; and, a replaceable desiccant dryer removably connected with
the vaporizer for drying the air in which the vapor is being entrained.
2. The system as set forth in claim 1 wherein the desiccant dryer
includes: a tubular chamber with end closures at either end; a desiccant
material in the tubular chamber; an inlet aperture defined in one
end closure and an outlet aperture defined in an opposite end closure;
annular gaskets surrounding the apertures of the end closures.
3. The system as set forth in claim 2 wherein the desiccant cartridge
further includes: a screen element at each end aperture for retaining
the desiccant material within the tubular element; and removable
seals closing the end apertures to prevent humidity from entering
the desiccant cartridge before the seals are removed.
4. The system as set forth in claim 2 further including: a window
disposed in one of the end closures.
5. The peroxy vapor system as set forth in claim 1 further including:
a clamping unit which receives and clamps a desiccant cartridge
through which air is drawn to dry the air.
6. The system as set forth in claim 5 wherein the clamping element
includes: a pair of end elements; a piston mounted in one of the
end elements, the piston having a sealing face for engaging a cartridge
gasket in a sealing relationship therewith; a second gasket sealing
face on the other end element; a mechanism for retracting the piston
to facilitate removal of a saturated desiccant cartridge and receipt
of an unsaturated desiccant cartridge.
7. The system as set forth in claim 6 wherein the clamping unit
further includes: springs for biasing the piston into contact with
the desiccant cartridge; and, wherein the retracting mechanism includes
a manually operable lever which is operated to move the piston against
the springs retracting it.
8. The system as set forth in claim 6 further including: an alignment
bracket associated with each end element for aligning the desiccant
cartridge gaskets with the gasket sealing faces of the clamping
unit.
9. The system as set forth in claim 6 wherein the vaporizer unit
includes a pair of projecting nipples, each having a latch engaging
surface; and wherein the end elements each include: a bore for receiving
one of the nipples in a fluid-tight arrangement, and a latch arrangement
for engaging the nipple latch engaging surface for latching the
end elements to the nipples.
10. The system as set forth in claim 1 wherein the desiccant dryer
includes a desiccant cartridge which has a moisture absorption capacity
matched to a volume of liquid in a peroxy solution cartridge that
is received in the liquid peroxy solution interface.
11. The system as set forth in claim 1 further including: a pair
of nipples for interconnecting the dryer with the vaporizer and
a source of air; the dryer including: a desiccant chamber connected
between end pieces, each end piece including a bore that receives
one of the nipples in a fluid tight relationship, and a latch for
latching the end pieces to the nipples.
12. The system as set forth in claim 11 wherein the desiccant chamber
is detachable from the end elements, the end elements including:
a piston mounted in one of the end elements, the piston having a
sealing face for engaging one face of the desiccant chamber in a
sealing relationship therewith; a second sealing face on the other
end element; a mechanism for retracting the piston to facilitate
removal of a saturated desiccant chamber and receipt of a replacement
desiccant chamber.
13. The system as set forth in claim 1 further including: a regeneration
oven for regenerating saturated desiccant dryers.
14. A means for generating peroxy vapor including: a means for
connecting a source of liquid peroxy solution with an interface
for a vaporizer; a means for vaporizing the liquid peroxy solution
and entraining the vapor in dry air; a means for supplying the entrained
peroxy vapor and air to a point of use; returning air, water vapor,
and peroxy vapor from the point of use through a replaceable desiccant
dryer; and a means for releasing the desiccant dryer when or before
the desiccant dryer becomes saturated, and receiving an unsaturated
replacement desiccant dryer.
15. A replaceable desiccant cartridge for a vapor hydrogen peroxide
generating system that includes a liquid peroxy solution cartridge
interface for interconnection with cartridges of liquid peroxy solution,
a vaporizer for vaporizing the liquid solution and entraining the
vapor in dry air, a unit which receives the desiccant cartridge
to supply the dry air to the vaporizer, the discharge unit including
a pair of elements one of which includes a dry air discharge passage
and the other includes a humid air supply passage, the desiccant
cartridge being received by the pair of elements in a fluid tight
relationship, a piston mounted in one of the end elements, the piston
having a sealing face, a second sealing face on the other end element,
the sealing faces facing each other to receive the desiccant cartridge
therebetween, and a mechanism for retracting the piston to facilitate
removal of a saturated desiccant cartridge and receipt of an unsaturated
desiccant cartridge, the disposable desiccant cartridge comprising:
a tubular chamber with end closures at either end; a desiccant material
received in the tubular chamber; an inlet aperture defined in one
end closure and an outlet aperture defined in an opposite end closure;
annular gaskets surrounding the apertures of the end closures; a
screen element at each end aperture for retaining the desiccant
material within the tubular element; and removable seals closing
the end apertures to prevent humidity from entering the desiccant
cartridge before the seals are removed.
16. A dryer for a vapor peroxy generation system including: a vaporizer
which vaporizes a peroxy composition and water solution and entrains
the vapor in dry air; a peroxy vapor discharge outlet through which
the peroxy vapor and air are discharged; a vapor and air recovery
inlet into which partially spent peroxy vapor, water vapor, and
air are returned; a dry air inlet nipple projecting from the peroxy
vapor unit for supplying the dry air to the vaporizer, the inlet
nipple having a latch engaging surface; a recovered air and vapor
discharge nipple having a latching surface; the dryer comprising:
a first end element having a bore for receiving the dry air inlet
nipple in a fluid-tight relationship, a second end element having
a bore for receiving the recovered air and vapor discharge nipple
in a fluid-tight relationship, a desiccant chamber connected between
the first and second end elements, a first latch mounted to the
first end element for engaging the dry air inlet nipple latching
surface for latching the first end element to the dry air inlet
nipple, a second latch mounted to the second end element for engaging
the received air and vapor discharge nipple latch surface for latching
the second end element to the recovered air and vapor discharge
nipple.
17. The dryer as set forth in claim 16 further including: a piston
mounted in one of the end elements, the piston having a sealing
face for engaging one end of a desiccant cartridge in a sealing
relationship therewith; a means for retracting the piston to facilitate
removal of a saturated desiccant cartridge and receipt of an unsaturated
desiccant cartridge.
18. The dryer as set forth in claim 17 further including: springs
for biasing the piston assembly into contact with the desiccant
cartridge; and, wherein the retracting means includes a manually
operable lever which is operated to move the piston against the
springs retracting it.
19. The dryer as set forth in claim 17 further including: an alignment
bracket associated with each end piece for aligning the desiccant
cartridge with the sealing surfaces of the end elements.
20. The dryer as set forth in claim 16 further including: a desiccant
cartridge regeneration system which receives the end elements and
interconnected desiccant chamber and regenerates the desiccant therein.
21. A disposable desiccant cartridge comprising: a tubular chamber
with end closures at either end; a desiccant material received in
the tubular chamber; an inlet aperture defined in one end closure
and an outlet aperture defined in an opposite end closure; annular
gaskets surrounding the apertures of the end closures; a screen
element at each end aperture for retaining the desiccant material
within the tubular element; and removable seals closing the end
apertures to prevent humidity from entering the desiccant cartridge
before the seals are removed.
22. A quick connect/disconnect desiccant dryer comprising: (a)
an upper portion and a lower portion that are spaced apart and a
container extending between the upper portion and the lower portion,
the container holding a desiccant, the upper portion having an input
port and an output port, the lower portion having an input port
and an output port, the output port of the upper portion fluidly
connected to a first port of the container and the input port of
the lower portion fluidly connected to a second port of the container;
and, (b) at least one clamp located on the apparatus engageable
with a fixture located on a device to securely affix the dryer to
the device.
23. The dryer as set forth in claim 22 wherein the container includes
a cartridge removably mounted between the upper and lower portions,
the cartridge including: (a) a tubular element with opposite ends
closed by a top element and a bottom element; (b) a first port located
on the top element and a second port located on the bottom element,
the first port and the second port fluidly connected, the desiccant
located within the tubular element such that a carrier gas passes
through the desiccant as the gas moves from the second port to the
first port, the first port located on the top of the container such
that when the container is positioned between the upper and lower
portions, the first port of the container aligns with the input
port of the upper portion and the second port of the container aligns
with the output port of the lower portion; (c) sealing means circumferentially
located around the first port and the second port of the container
such that when the container is clamped between the upper portion
and the lower portion, the input port of the upper portion and the
first port of the cartridge are sealed from the atmosphere and the
output port of the lower portion and the second port of the container
are sealed from the atmosphere.
24. A quick connect/disconnect apparatus comprising: (a) a holder
having a first portion and a second portion, the first and second
portions rigidly connected and spaced apart so as to receive a cartridge
therebetween, the first portion having an input port and an output
port, the second portion having an input port and an output port,
the output port of the first portion fluidly connectable to a first
port of the cartridge and the input port of the second portion fluidly
connectable to a second port of the cartridge; (b) the first portion
of the holder having a clamping mechanism operable after the cartridge
has been placed in the holder to clamp the cartridge between the
first portion and the second portion such that the output port of
the first portion is in alignment with the first port of the cartridge
and the input port of the second portion is in alignment with the
second port of the container; and, (c) at least one clamp located
on the holder engageable with a fixture located on a device to securely
affix the holder to the device.
25. The apparatus as set forth in claim 24 wherein said at least
one clamp is located on the first portion further including a second
clamp located on the second portion; and wherein said fixture includes
a first nipple and a second nipple, both the first and second nipples
extending from the device, the first nipple having a collar, the
collar located close to the device, the first nipple dimensioned
to fit snugly within the input port of the first portion, the second
nipple dimensioned to fit snugly within the output port of the second
portion and the clamp engageable with said collar to secure said
holder to said device.
26. The apparatus of claim 25 wherein the input port of the first
portion and the output port of the second portion further include
sealing means located within the input port of the first portion
and the output port of the second portion so as to effect an air
tight seal with said first and second nipples when said nipples
are positioned within said input port of the first portion and said
output port of the second portion.
27. A method of generating peroxy vapor including: connecting a
source of liquid peroxy solution with an interface for a vaporizer;
vaporizing the liquid peroxy solution and entraining the vapor in
dry air; supplying the entrained peroxoy vapor and air to a point
of use; returning air, water vapor, and peroxy vapor from the point
of use through a replaceable desiccant dryer; and releasing the
desiccant dryer when or before the desiccant dryer becomes saturated,
receiving an unsaturated replacement desiccant dryer.
28. The method as set forth in claim 27 wherein the desiccant dryer
includes a cartridge and further including: clamping the unsaturated
desiccant dryer in a flow path leading to the vaporizer; and, unclamping
a saturated desiccant dryer from the flow path for replacement with
an unsaturated cartridge.
29. The method as set forth claim 28 wherein the source of peroxy
liquid includes a canister containing a preselected volume of peroxy
liquid and further including: loading a amount of desiccant in the
cartridge which is sufficient to absorb the preselected volume.
30. The method as set forth in claim 27 further including: regenerating
the saturated desiccant cartridge; attaching temporary seals to
openings into the cartridge to prevent the regenerated desiccant
from absorbing moisture; and, before reinstalling the regenerated
cartridge, opening the seals.
Description [0001] This application claims the benefit of U.S. Provisional
application Serial No. 60/361129 filed Feb. 28 2002.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to the peroxy vapor treatment
arts, more particularly to hydrogen peroxide vapor sterilization
and disinfection. The invention finds particular application in
conjunction with hydrogen peroxide vapor sterilization systems in
which peroxide vapor is entrained in dry air which has been dried
with a desiccant and will be described with particular reference
thereto. It is to be appreciated that the present invention may
be used with other peroxy vapors in conjunction with disinfection,
sanitation, and other treatment processes.
[0003] Heretofore, a solution of hydrogen peroxide and water have
been vaporized and entrained in dry air. The vapor and air are pumped
into a sterilization or other treatment chamber. The hydrogen peroxide
reacts with microbial and other decontaminants in an oxidizing reaction
which deactivates them and converts the vapor molecule from peroxide
to water. To maintain a preselected concentration of hydrogen peroxide
in the chamber, air and vapor from the chamber are recirculated
to the vaporizer. Hydrogen peroxide vapor in the withdrawn air is
decomposed catalytically or by heat to water vapor. The water vapor
is then removed from the air, leaving dry air to be recirculated
to the vaporizer.
[0004] One technique for drying the air was by condensation. However,
condensation requires relatively expensive compressors and refrigeration
units. Moreover, such condensation units typically fail to dry the
air to a consistent level of humidity.
[0005] Consistent and lower level of humidity have been achieved
by passing the air and water vapor through a desiccant. Although
desiccants dry the air consistently to a low humidity, it typically
takes longer to regenerate a desiccant than to saturate it. One
way to meet these demands was through the use of a desiccant wheel.
The air and water vapor were passed through a first portion or section
of a desiccant wheel until that section became substantially saturated.
The wheel was then indexed, bringing a new desiccant portion or
section into the air and water vapor flow path. The saturated portion
of the desiccant was subject to a regeneration process over the
next several indexed positions of the wheel. Such onboard systems
for regenerating desiccant were not only expensive and mechanically
complex, but also added significant weight and bulk to portable
hydrogen peroxide generation systems.
[0006] The present invention provides a new and improved desiccant
drying system which overcomes the above-referenced problems.
SUMMARY OF THE INVENTION
[0007] In accordance with one aspect of the present invention,
a peroxy vapor system includes a liquid peroxy solution interface
for receiving a source of liquid peroxy solution. A vaporizer vaporizes
the liquid peroxy solution and entrains it in air. A replaceable
desiccant dryer is connected with the vaporizer for drying the air.
[0008] In accordance with another aspect of the present invention,
a replaceable desiccant cartridge is provided for a vapor hydrogen
peroxide generating system that includes a liquid peroxy solution
cartridge interface for interconnection with cartridges of liquid
peroxy solution, a vaporizer for vaporizing the liquid solution
and entraining the vapor in air, a clamping unit which receives
the desiccant cartridge to supply the dry air to the vaporizer,
the clamping unit including a pair of end elements between which
the desiccant cartridge is received, a piston mounted in one of
the end elements which piston has a sealing face, a second sealing
face on the other end element with the sealing faces facing each
other to receive the desiccant cartridge therebetween, and a mechanism
for retracting the piston to facilitate removal of a saturated desiccant
cartridge and receipt of an unsaturated desiccant cartridge. The
disposable desiccant cartridge includes a tubular chamber with enclosures
at either end and a desiccant material received in the tubular chamber.
An inlet aperture is defined in one end closure and an outlet aperture
is defined in the opposite end closure. Annular gaskets surround
the apertures of the end closures. A screen element at each end
aperture retains the desiccant material within the tubular element.
Removable seals close the end apertures to prevent humidity from
entering the desiccant cartridge before the seals are removed.
[0009] In accordance with another aspect of the present invention,
a dryer is provided for a vapor peroxy generation system which includes
a vaporizer for vaporizing a peroxy composition and water solution
and entraining the vapor in dry air, a peroxy vapor discharge outlet
through which the peroxy vapor and air are discharged, a vapor and
air recovery inlet into which partially spent peroxy vapor, water
vapor, and air are returned, a dry air inlet nipple projecting from
the peroxy vapor unit for supplying the dry air to the vaporizer,
which inlet nipple has a latch engaging surface, and a recovered
air and vapor discharge nipple also having a latching surface. The
dryer includes a first end element having a bore for receiving the
dry air inlet nipple in a fluid tight relationship and a second
end element having a bore for receiving the recovered air and vapor
discharge nipple in a fluid tight relationship. A desiccant chamber
is connected between the first and second end elements. A first
latch mechanism mounted to the first end element engages the dry
air inlet nipple latching surface for latching the first end element
to the dry air inlet nipple. A second latch mounted to the second
end element engages the recovered air and vapor discharge nipple
latch surface for latching the second end element to the recovered
vapor and air discharge nipple.
[0010] In accordance with another aspect of the present invention,
a quick connect/disconnect apparatus is provided. A holder has a
first portion and a second portion. The first and second portions
are rigidly connected and spaced apart so as to receive a cartridge
therebetween. The first portion has an inlet port and an outlet
port. The second portion also has an inlet port and an outlet port.
The outlet port of the first section is fluidicly connectable to
a first port of the cartridge and the inlet port of the second portion
is fluidicly connectable to the second port of the container. The
first portion of the holder has a clamping mechanism operable after
the cartridge has been placed in the holder to clamp the cartridge
between the first and second portions such that the output port
of the first portion is in alignment with the first port of the
container and the input port of the second portion is in alignment
with the second port of the container. At least one clamp is located
on the holder engageable with a fixture located on a device to securely
affix the holder to the device.
[0011] In accordance with another aspect of the present invention,
a quick connect/disconnect desiccant dryer is provided. An upper
portion and a lower portion are spaced apart and a container is
rigidly affixed to the apparatus that extends between the upper
portion and the lower portion. The container holds a desiccant.
The upper portion and the lower portion each have an input port
and an output port. The output port of the upper portion is fluidicly
connected to a first port of the container; and the input port of
the lower portion is fluidicly connected to the second port of the
container. At least one clamp which is located on the apparatus
is engageable with a fixture located on a device to securely affix
the dryer to the device.
[0012] One advantage of the present invention resides in its simplicity
and low cost.
[0013] Another advantage of the present invention resides in the
assurance of adequate desiccant drying capacity.
[0014] Another advantage of the present invention resides in the
assurance of dry air with a predictable low humidity level.
[0015] Still further advantages of the present invention will become
apparent to those of ordinary skill in the art upon reading and
understanding the following detailed description of the preferred
embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The invention may take form in various components and arrangements
of components, and in various steps and arrangements of steps. The
drawings are only for purposes of illustrating a preferred embodiment
and are not to be construed as limiting the invention.
[0017] FIG. 1 is a diagrammatic illustration of a hydrogen peroxide
vapor decontamination system in accordance with the present invention;
[0018] FIG. 2 is a side-view of the peroxy vapor generation system;
[0019] FIG. 3 is an end-view of the system of FIG. 2;
[0020] FIG. 4 is a top view of the vaporizer unit and disposable
dryer cartridge embodiment of FIGS. 2 and 3;
[0021] FIG. 5 is an enlarged view of the desiccant cartridge of
FIGS. 2-4;
[0022] FIG. 6 is an enlarged sectional view of an end portion of
the cartridge of FIG. 5;
[0023] FIG. 7 is a side-sectional view of the desiccant cartridge
receiving assembly of FIGS. 2-4;
[0024] FIG. 8 is a front view of an upper portion of the assembly
of FIG. 7;
[0025] FIG. 9 is a top view of the assembly of FIG. 7;
[0026] FIG. 10 is an side view of the vaporizer system of FIG.
2 with an alternate, reusable dryer;
[0027] FIG. 11 is an end view of the alternate embodiment of FIG.
10;
[0028] FIG. 12 is a top view of the vaporizer unit and reusable
dryer cartridge embodiment of FIGS. 10 and 11 with front access
panel doors partially open;
[0029] FIG. 13 is a side sectional view of the reusable dryer cartridge
of FIGS. 10-12; and
[0030] FIG. 14 is a diagrammatic illustration of a regenerator
unit for the cartridge of FIGS. 10-13.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0031] With reference to FIGS. 1 2 3 and 4 a vapor generation
unit 10 vaporizes a peroxy solution from a solution source 12 and
entrains the vapor in dry air which has been dried by a dryer 14.
The dry air and vapor are conveyed to a treatment chamber, such
as an isolator 16.
[0032] In the preferred embodiment, the peroxy solution source
is a container or cartridge of hydrogen peroxide in water solution
which is received in a cartridge interface 20. Once in the cartridge
interface, the cartridge is interconnected with a dip tube assembly
for withdrawing the solution. Although a solution of hydrogen peroxide
in water vapor is preferred, other solutions are contemplated, such
as peracetic acid and water, other peroxy compounds and water, peroxy
compounds in alcohol and water, and the like. In a preferred embodiment,
the hydrogen peroxide and water solution is 35-50% hydrogen peroxide.
[0033] The vaporizer system includes an injection pump 22 which
injects metered amounts of the peroxy solution into a vaporizer
24. The vaporizer, in a preferred embodiment, is a heated surface,
such as a heated plate or the interior surface of a bore onto which
the peroxy solution is sprayed or injected forming peroxy and water
vapor. Dry air from the dryer 14 is preheated in a preheater 26
and supplied to the vaporizer to entrain the hydrogen peroxide or
other peroxy vapor and water vapor. The vapor entrained in the air
is supplied to the treatment chamber 16.
[0034] In the treatment chamber, hydrogen peroxide vapor interacts
with microbes and other contaminants in an oxidation reaction, deactivating
the microbial material and leaving water vapor suspended in the
air. Thus, with time, the concentration of hydrogen peroxide in
the treatment chamber drops. To maintain the concentration of hydrogen
peroxide vapor, a portion of the vapor and air is withdrawn and
fed through a destroyer 28 such as copper pellets. The copper pellets
catalytically degrade the remaining peroxide vapor into water vapor
and oxygen. A blower 30 which provides the motive force to move
the air and vapor, pumps the air and water vapor to the dryer 14.
Desiccant in the dryer absorbs the water vapor such that air of
accurately predictable low humidity is discharged to the preheater
26. In this manner, air of known humidity is supplied to the vaporizer,
permitting the vaporizer to optimize the concentration of peroxide
vapor without condensation. It will be noted that if a significant
amount of unexpected water vapor were returned to the vaporizer,
the additional vapor content of the saturated air could push the
total vapor content of one or both of the peroxide and the water
vapor beyond the condensation point.
[0035] In a preferred embodiment, the dryer 14 includes a disposable
desiccant cartridge 40 which is clamped into a clamping assembly
42.
[0036] With reference to FIGS. 5 and 6 the desiccant cartridge
includes a cylindrical tube 44 which is closed at either end with
end caps 46 to form a cartridge of preselected length. Apertures
48 are defined centrally in each end cap to allow for the passage
of gas into and out of the cartridge. The apertures are covered
on the inside by disks 50 of screening material to retain a desiccant
52. A water vapor impermeable end seal 54 is adhesively adhered
over an exterior of each opening to prevent the desiccant within
the cartridge from absorbing water vapor before it is mounted in
the clamping assembly 42. The aperture in each end is surrounded
by a resilient gasket 56 such as a closed cell foam of a material
which is inert to hydrogen peroxide or other circulated gases.
[0037] With reference again to FIGS. 2 and 3 and further reference
to FIGS. 7 8 and 9 the clamping assembly 42 includes a pair of
end elements 60 62 and pair of tie angles 64 which maintain the
end pieces 60 62 in a preselected, fixed spaced relationship. The
lower end element 62 includes an inlet connection port or bore 70
for interconnection with an outlet nipple 72 of the vapor generator
assembly 10. A latch assembly 74 engages a lip 76 around the outlet
nipple to maintain the clamping assembly 42 attached to the vapor
generator. The inlet port includes an L-shaped passage terminating
in an outlet port 78 adjacent an inlet to the cartridge. The lower
assembly has a smooth sealing face 80 surrounding the outlet port
78 to provide an air-tight seal with the lower gasket 56. The lower
assembly includes an upstanding, semi-circular guide portion 82
which receives and positions a lower end of the cartridge centered
on the outlet port 78.
[0038] The upper element 60 includes an outlet port 90 which is
dimensioned to be received in a fluid-tight relationship with a
nipple 92 of an inlet port for dry gas on the vaporizer unit 10.
A latch assembly 94 locks the upper element to the nipple assembly
lip 95. The upper element 60 includes an L-shaped passage terminating
in an inlet port 96. The inlet port 96 is surrounded by a piston
98 of larger diameter than the gasket 56 of the desiccant cartridge.
The piston defines a smooth, polished sealing face 100 which forms
a sealing relationship with the desiccant cartridge gasket. The
piston 98 is retracted by pulling a handle 102 toward the user,
away from the vaporizing unit 10. Springs 104 bias the piston toward
engagement with the gasket of the desiccant cartridge. When a desiccant
cartridge is to be inserted, the handle 102 is pushed away from
the user, retracting the piston. This loosens the seal between the
piston and the gasket of the used desiccant cartridge which is removed.
The adhesive seals 54 of the new desiccant cartridge are removed
and the desiccant cartridge is inserted into the latching unit 40
until its rear surfaces engage the alignment surface 84 of the lower
element 62 and a matching alignment surface 106 of the upper element
60. The handle 102 is returned to the angled position allowing the
springs 104 to bias the sealing face 100 of the piston 98 into a
fluid-tight seal with the upper gasket of the desiccant cartridge.
An O-ring 108 between the piston 98 and the upper element 60 prevents
vapor from passing between the piston and the upper end element.
[0039] In one preferred embodiment, the desiccant cartridge is
sized in accordance with the anticipated hydrogen peroxide consumption.
In one embodiment, the dryer is sized to accommodate the moisture
from one cycle of the largest enclosure under worst case conditions.
In this embodiment, the desiccant cartridge is replaced at the beginning
of each cycle. In another embodiment, the desiccant cartridge is
sized to absorb all of the water vapor that is generated by the
contents of the hydrogen peroxide cartridge. In this embodiment,
the desiccant cartridge is replaced each time the hydrogen peroxide
cartridge is replaced. In another embodiment, the desiccant cartridge
is sized to be able to hold the water generated by a plurality of
the hydrogen peroxide cartridges. As yet another alternative, the
desiccant cartridge includes an indicator which provides a visual
indication that the cartridge is nearing saturation and should be
replaced. As yet another alternative, the vaporization unit 10 includes
a moisture sensor which senses the humidity of the air entering
the preheater. When the humidity starts to rise, the vaporization
unit provides a visual or audio signal indicating that the desiccant
cartridge 40 is due for replacement.
[0040] As another alternative, the alignment surfaces 82 106 have
projections that are received in corresponding recess in the cartridge
40 to ensure accurate alignment. In another alternative, mating
surface 80 of the lower element 62 and the lower end cap have mating
projections and recesses outside of the perimeter of the gasket
56 to assure alignment. When the handle 102 is pushed to retract
the piston, a pawl holds the piston 98 retracted. A projection or
element on the upper end cap interacts with the pawl directly or
through a connecting linkage to release the piston only when the
top of the cartridge is properly received to release the piston.
As another option, cutters can be provided on the lower element
62 and the piston 98 to open the end seals 54 when the cartridge
is properly aligned.
[0041] With reference to FIGS. 10-13 in another embodiment, a
dryer cartridge 40' is attached directly to the nipples 72 92 of
the vaporizer unit 10. This embodiment includes a first or top element
60' and a second or lower end element 62' which are interconnected
by a desiccant cylinder 44'. The upper end element includes a bore
90' with a gasket configured to receive the uppermost nipple 92
in a fluid-tight relationship; and the lower end element defines
a lower well 70' and a gasket 56' configured to receive the lower
nipple 72 in a fluid tight seal. A lower latch 74' engages the latching
surface of the lower nipple 72 and an upper latch 94' engages the
latch surface of the upper nipple 92. Screen elements 50' are disposed
adjacent upper and lower outlets of the cartridge to contain a desiccant
52' therebetween. A glass sight 110 enables the operator to view
a lower desiccant chamber 112 that is defined between a pair of
the lower screens 50'. The color of the desiccant is an indication
to the user whether or not a dryer has been regenerated. In the
preferred embodiment, the desicacant turns clear soon after the
dryer is put in use. The desiccant turns color (blue in this case)
after regeneration.
[0042] Preferably, all components of the reusable desiccant cartridge
are constructed of metal or other materials capable of withstanding
repeated exposure to temperatures on the order of 150.degree. C.
Alternately, the cartridge can be a single use cartridge that is
disposed after being used.
[0043] When the desiccant cartridge is saturated or cannot hold
the moisture generated by the next cycle to be run, the latches
74', 94' are released and the drying cartridge is removed and replaced
with a regenerated cartridge. With reference to FIG. 14 the saturated
cartridge is placed in a regeneration unit 120. The regeneration
unit includes nipples of the same size and spacing as nipples 72
92 in the second embodiment which are plug into the passages 70',
90'. For cartridges of the embodiment of FIG. 5 the manifold 128
includes mating top and bottom connections. The regeneration unit
includes a filter, preferably a HEPA filter 122 which removes airborne
contaminants. A blower 124 blows the filtered air through a heater
126 to a manifold 128. The manifold is connected with one or more
desiccant cartridges 40' which are to be regenerated. The heated
air, heated to about 150.degree. C., is blown through the desiccant
entraining the absorbed water, and discharged to the atmosphere.
After the desiccant is fully regenerated, as determined by measuring
the temperature of the discharged air with a temperature switch
130 based on time, or other factors, the circulation of heated
air through the desiccant is stopped and a cooling fan 132 is started.
The cooling fan cools the desiccant cartridge back to room temperature
while the ports of the cartridge remain closed. A lockable door
134 is released once the desiccant cartridges have cooled to a temperature
that is safe to handle. The desiccant cartridges remain connected
to the manifold to prevent the cooling air from entering the chambers
where humidity from the cooling air would be absorbed.
[0044] The invention has been described with reference to the preferred
embodiment. Obviously, modifications and alterations will occur
to others upon reading and understanding the preceding detailed
description. It is intended that the invention be construed as including
all such modifications and alterations insofar as they come within
the scope of the appended claims or the equivalents thereof. |