U.S. patent application number 11/029994 was filed with the patent office on 2005-08-18 for kitchen ventilation degreasing system.
Invention is credited to Lipford, Brian, Lipford, Keith, Marshall, John, Way, Joe.
Application Number | 20050178378 11/029994 |
Document ID | / |
Family ID | 34840415 |
Filed Date | 2005-08-18 |
United States Patent
Application |
20050178378 |
Kind Code |
A1 |
Marshall, John ; et
al. |
August 18, 2005 |
Kitchen ventilation degreasing system
Abstract
The present invention is a permanently installed automatic
kitchen ventilation degreasing system. The system includes a
cascading cleaning mechanism and drainage mechanism. A water feed
tube carries water and cleaning agents to a conduit secured and
centered within the ventilation ducts. The water and cleaning
agents are sprayed in a cascading manner along the inner surface of
the duct by spray nozzles located on nozzle blocks spaced at
intervals along the conduit. The flow of solvent or rinse water
through the nozzles is controlled by solenoid valves which are
controlled by a programmable controller. The liquid run off is
collected by a deflector and drained.
Inventors: |
Marshall, John; (Fallston,
MD) ; Way, Joe; (Abingdon, MD) ; Lipford,
Keith; (Severna Park, MD) ; Lipford, Brian;
(Bel Air, MD) |
Correspondence
Address: |
LAW OFFICES OF ROYAL W. CRAIG
SUITE 153
10 NORTH CALVERT STREET
BALTIMORE
MD
21202
US
|
Family ID: |
34840415 |
Appl. No.: |
11/029994 |
Filed: |
January 5, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60534325 |
Jan 5, 2004 |
|
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|
Current U.S.
Class: |
126/299D ;
126/299R |
Current CPC
Class: |
F24C 15/2057
20130101 |
Class at
Publication: |
126/299.00D ;
126/299.00R |
International
Class: |
F24C 015/20 |
Claims
We claim:
1. A ventilation degreasing system for cleaning the interior
surfaces of a kitchen ventilation duct, comprising: a duct conduit
in fluid communication with a water source, and a cleaning solution
source, said duct conduit comprising a plurality of conduit
segments attached to a corresponding plurality of nozzle blocks,
each nozzle block having a plurality of nozzles, the duct conduit
extending substantially the length of said ventilation duct; a
programmable controller connected to a plurality of solenoid valves
for controlling distribution of cleaning solvent or water into said
duct conduit and to said nozzles; a drainage assembly for or
capturing liquid run-off in said kitchen ventilation duct during
operation of said degreasing system; and a plurality of support
arms for supporting said duct conduit centrally in the kitchen
ventilation duct.
2. The ventilation degreasing system according to claim 1, wherein
each of said duct centering support arms comprises distal rollers
at each end, and a spring mechanism for imparting lateral spring
between said rollers.
3. The ventilation degreasing system according to claim 1, wherein
said cleaning solution source comprises a venturi inlet connected
to a cleaning solution reservoir and to said water source for
inducting cleaning solution into said duct conduit.
4. The ventilation degreasing system according to claim 1, wherein
said drainage assembly comprises a deflector formed from a metal
sheet with an upper portion that hooks over an existing removable
filter in said kitchen ventilation hood to thereby anchoring the
deflector inside the kitchen ventilation system.
5. The ventilation degreasing system according to claim 1, wherein
said drainage assembly comprises a catch basin beneath the kitchen
ventilation system with a drain pipe connected thereto for drainage
into a removal vessel.
6. A ventilation degreasing system for cleaning the interior
surfaces of a kitchen ventilation duct, comprising: a multi-stage
duct conduit in fluid communication with a water source, and a
cleaning solution source, said multi-stage duct conduit comprising
at least an upper stage duct conduit with a plurality of nozzle
blocks and associated nozzles supported inside said kitchen
ventilation duct along an upper extent thereof, and a lower stage
duct conduit with a plurality of nozzle blocks and associated
nozzles supported inside said kitchen ventilation duct along a
lower extent thereof; the multi-stage duct conduit collectively
extending substantially the length of said kitchen ventilation
duct; a programmable controller connected to a plurality of
solenoid valves for selectively controlling distribution of
cleaning solvent or water into one of said upper or lower stages of
said multi-stage duct conduit and out from the nozzles thereof.
7. The ventilation degreasing system according to claim 6, wherein
each of said duct centering support arms comprises distal rollers
at each end, and a spring mechanism for imparting lateral spring
between said rollers.
8. The ventilation degreasing system according to claim 6, wherein
said cleaning solution source comprises a venturi inlet connected
to a cleaning solution reservoir and to said water source for
inducting cleaning solution into said duct conduit.
9. The ventilation degreasing system according to claim 1, wherein
said drainage assembly comprises a deflector formed from a metal
sheet with an upper portion that hooks over an existing removable
filter in said kitchen ventilation hood to thereby anchoring the
deflector inside the kitchen ventilation system.
10. The ventilation degreasing system according to claim 6, wherein
said drainage assembly comprises a catch basin beneath the kitchen
ventilation system with a drain pipe connected thereto for drainage
into a removal vessel.
11. A ventilation degreasing system for cleaning the interior
surfaces of a kitchen ventilation system inclusive of ventilation
duct and hood, comprising: a duct conduit in fluid communication
with a water source and cleaning solution source, said duct conduit
comprising a plurality of nozzle blocks and associated nozzles
supported inside said kitchen ventilation duct and extending
substantially the full length of said kitchen ventilation duct; a
hood conduit in fluid communication with said water source and
cleaning solution source, said hood conduit comprising a plurality
of nozzle blocks and associated nozzles supported inside said
kitchen ventilation hood and extending substantially the full
length of said kitchen ventilation hood; a programmable controller
connected to a plurality of solenoid valves for selectively
controlling distribution of cleaning solvent or water into one of
said duct conduit and hood conduit and out from the nozzles
thereof.
12. The ventilation degreasing system according to claim 11,
further comprising a duct support framework for supporting said
duct conduit centrally and vertically in said duct, and a hood
support framework for supporting said hood conduit centrally and
horizontally in said hood.
13. The ventilation degreasing system according to claim 12,
wherein said duct support framework includes a plurality of support
arms for supporting said duct conduit centrally in the kitchen
ventilation duct.
14. The ventilation degreasing system according to claim 13,
wherein each of said plurality of support arms comprises distal
rollers at each end, and a spring mechanism for imparting lateral
spring between said rollers.
15. The ventilation degreasing system according to claim 11,
wherein said cleaning solution source comprises a venturi inlet
connected to a cleaning solution reservoir and to said water source
for inducting cleaning solution into said duct conduit.
16. The ventilation degreasing system according to claim 11,
further comprising a drainage assembly for draining runoff cleaning
solution and water into a disposal vessel.
17. The ventilation degreasing system according to claim 16,
wherein said drainage assembly comprises a deflector formed from a
metal sheet with an upper portion that hooks over an existing
removable filter in said kitchen ventilation hood to thereby
anchoring the deflector inside the kitchen ventilation system.
18. The ventilation degreasing system according to claim 17,
wherein said drainage assembly comprises a catch basin beneath the
kitchen ventilation system with a drain pipe connected thereto for
drainage into a removal vessel.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application derives priority from Provisional
Patent Application No. 60/534,325 filed Jan. 5, 2004.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates generally to the field of
spray applicators for cleansing the interior surfaces of enclosed
spaces and, more particularly, to a fully automated spray
degreasing system for cleansing elongated enclosed spaces such as
in kitchen ventilation systems and the like.
[0004] 2. General Background
[0005] Kitchen ventilation ducts are typically required by code to
remove smoke, air borne grease, and by-products of cooking from
commercial kitchen areas and particularly from the area directly
over the stove-tops. However, air-borne grease as it cools commonly
accumulates on the inside walls of the ventilation ducts, thereby
creating a grease-fire hazard. Periodic degreasing of the kitchen
ventilation ducts on a regular basis is recommended and, for
commercial kitchens, often mandated by state and federal
regulations.
[0006] Traditionally, degreasing kitchen ventilation ducts is
accomplished by snaking high pressured hot water jetting nozzles
into a duct and hand directing the cleaning. This method requires
multiple individuals to accomplish the task and is typically done
after normal working hours thereby requiring extra staff to remain
after normal closing hours. The process is cumbersome, messy and
typically exposes workers to hazardous chemicals. In addition,
visibility within the duct is minimal and verification of adequate
surface cleaning is difficult. Fluid run off is typically collected
into sheets beneath the flue, directed in to buckets and drained or
manually cleaned-up from the floor.
[0007] There have been past efforts to develop automatic cleaning
devices to clean ventilation ducts is disclosed in the prior art
and typically involves the use of conduit permanently installed
inside the ventilation duct for carrying water or cleaning fluid.
The conduit is centrally-secured by multiple struts, and water or
cleaning fluid is discharged under pressure towards the duct walls
either directly through a plurality of holes in the conduit or
through some other mechanism (i.e. sprinkler heads).
[0008] For example, U.S. Pat. No. 4,031,910 to Lawson on Jun. 28,
1977 discloses an "Articulated Spray Applicator Particularly Suited
for Use in Cleaning Flues and the Like." The conduit of the spray
applicator is segmented, with the segments angularly joined such
that the conduit follows an angularly configured flue. Furthermore,
each conduit segment is joined together, plus mounted to the flue
wall, such that simultaneous unidirectional rotation may be
imparted upon each segment independently in response to the jetting
action of the fluid as it is expelled. The conduit is secured to
the flue using conventional support spiders. The specific structure
of the support spiders and the method of securing them to the flue
formed no part of the invention. As a practical matter a drip pan
is placed beneath the flue to collect run off.
[0009] U.S. Pat. No. 5,860,412 to Way et al., also included among
the present inventors, discloses a "Kitchen Duct Degreasing
System." This system uses a pump to both super-heat water and to
deliver it under pressure through conduit installed inside the
ventilation duct and out a plurality of nozzles. The nozzles are
opened and closed individually by an electronic programmable timer.
Multiple nozzles are placed at periodic intervals along the conduit
such that when activated the entire surface perimeter of the inside
of the duct is cleaned. To ensure adequate pressure the nozzles are
not operated simultaneously, but rather on a rolling or cascading
schedule, top to bottom. A water-tight deflector located at the
bottom of the duct captures run off so that it may be directed to a
suitable receptacle after degreasing. A programmable controller
operates the nozzles. The conduit is fixed attached to the duct
walls by any suitable means (i.e. support members under tension
against duct walls, welds, bolts, epoxy adhesive, etc.) and the
nozzles are fixedly attached to the conduit.
[0010] The systems described in the prior art references above,
address the problems related to hand directed duct cleaning
methods. However, these systems are expensive, difficult to
install, difficult to operate (they are not all fully automatic),
and are not entirely safe because they do not suggest a solution to
prevent the escape of caustic run off, or of aerosolized cleaning
solution.
[0011] Therefore, a need still exists for an effective and cost
efficient approach to the problem of grease accumulation upon the
interior surfaces of kitchen ventilation systems.
SUMMARY OF THE INVENTION
[0012] It is an object of the present invention to provide a method
and device for automatically degreasing the interior surfaces of
kitchen ventilation systems.
[0013] It is another object of the present invention to provide a
method and device for safely and economically degreasing the
interior surfaces of kitchen ventilation systems without need for
any hand held and directed equipment.
[0014] Another object of the present invention is to provide a
device for effectively degreasing the interior surfaces of kitchen
ventilation systems that can be permanently installed on-site,
either as original equipment with installation of the ducting or
retrofit into pre-existing systems.
[0015] Another object of the present invention is to provide a
device for effectively degreasing the interior surfaces of kitchen
ventilation systems that, depending on the length and height of the
ventilation system, may be connected directly to a pre-existing
water source and operate from existing pressure, thereby avoiding
the need for installing an expensive water pressurization
system.
[0016] Another object of the present invention is to provide a
kitchen ventilation system degreasing device further having a
venturi type injector connected to the water feed for injecting
cleaning agent concentrates into the water stream, as needed, for
more efficient degreasing of the interior surfaces of the kitchen
ventilation system.
[0017] It is a further object of the present invention to provide a
kitchen ventilation system degreasing device that employs the
existing ventilation grease drainage assembly in a modified
configuration to eliminate spray and leakage.
[0018] It is a further object of the present invention to provide
secondary grease-fire suppression in addition to its cleaning
capability.
[0019] It is also an object of the present invention to provide a
modular design for easily and efficiently installing, centering and
securing the conduit of the present invention inside the
ventilation systems.
[0020] The foregoing and other objects of are accomplished by
providing a kitchen ventilation system degreasing system that
includes (1) a duct conduit extending the length of a kitchen
ventilation duct from the intake to the exhaust, (2) a fixed top
support arm mounted to the ventilation system at a point beneath
the exhaust fan for suspending the conduit, (3) a hood conduit
extending the full length of the existing kitchen hood; (4) one or
more supports for attaching the kitchen hood conduit inside the
hood; (5) a water feed pipe connected to the intake end of the
conduits, (6) a venturi type injector connected to the water feed
for injecting cleaning agent concentrates into the water stream, as
needed; (7) a plurality of electric solenoid valves that enable
distribution of water with or without cleaning agent; (8) a
plurality of nozzles connected to nozzle blocks that are spaced at
intervals along the conduit for spraying the water/cleaning agent;
(9) a programmable controller connected to the solenoid valves;
(10) duct centering support arms for securing the conduit within
the kitchen ventilation system, and (11) a splash-proof run-off
drainage mechanism that makes use of the existing ventilation
grease-drain for draining cleaning solution and debris into a
receptacle for safe code-compliant removal.
[0021] The fixed top support arm suspends the duct conduit beneath
the exhaust fan, while the plurality of uniquely structured duct
centering support arms each comprise a spring-bar with wheels at
each end. The centering arms are attached to the conduit at
predetermined intervals. The conduit is fixed through the duct
centering support arms and is snaked into the kitchen ventilation
system from the exhaust end of the ventilation system. As the
conduit is snaked into the duct work, the wheels of the centering
arms roll along the interior surfaces of the duct, and the lateral
springiness of the centering arms accommodate bumps and unevenness,
thereby centering and guiding the conduit. Once the conduit is in
place it is fixed to the top support arm.
[0022] The hood conduit is positioned at the proper location to
allow spray to impinge upon all surfaces of the existing kitchen
hood behind the filters. The hood conduit is secured to the hood
with support(s) attached to the hood.
[0023] The system is fully automatic, employing a plurality of
electrically-controlled solenoid valves, solvent flow sensor, an
optional effluent cleanliness sensor, and a programmable controller
connected to each of the nozzle-valve blocks. The nozzle-blocks
each employ multiple spray nozzles connected to the conduit which
deliver water as well as a cleaning agent concentrate to the
interior surface of the ventilation duct.
[0024] The present system is able to operate from standard water
pressure and this suffices to drive the system due to (1) use of
efficient spray nozzles and (2) a particular conduit/valve
arrangement and cascading operation that maintains adequate
pressure on all nozzles. By virtue of the foregoing the nozzles
provide a spray that fully and accurately covers the targeted spray
area.
[0025] A cascading operation can be accomplished by regulating the
flow of water through stages of the conduit by the solenoid valves
connected to the programmable controller, such that only a single
stage of spray nozzles are operating at any given time. The
combination of high efficiency nozzles plus cascaded operation
allows the system to function without the need for an expensive
water pressurization system. There are generally 2-to-4 nozzles in
each nozzle block and 4 or more nozzle blocks per conduit stage.
The flow of solvent or rinse water is controlled through each stage
by one solenoid valve)
[0026] The liquid run-off from the degreasing process drains into
the existing grease collection system, but this is modified to
ensure that the system is splash-proof and drip-proof to improve
safety and avoid kitchen contamination.
BRIEF DESCRIPTION OF THE FIGURES
[0027] The following figures are illustrative of the preferred
embodiment of the present invention:
[0028] FIG. 1 is an isometric view of the outer surfaces of a
conventional kitchen ventilation system.
[0029] FIG. 2 is an illustration of the primary components of the
cleaning mechanism of the kitchen ventilation system degreasing
device of the present invention, as well as the support features,
with an exploded cross section of the nozzle-valve blocks including
the spray nozzles.
[0030] FIG. 3 is a perspective illustration of the duct nozzle
block of FIG. 2.
[0031] FIG. 4 is an exploded cross section of an exemplary venturi
injector.
[0032] FIG. 5 is a front perspective illustration of the hood
nozzle block of FIG. 2.
[0033] FIG. 6 is a perspective view of the hood nozzle block, hood
conduit, and supports of FIG. 2.
[0034] FIG. 7 is a side view of the hood nozzle block, hood
conduit, and supports of FIG. 2 and 6.
[0035] FIG. 8 is an isometric drawing illustrating one embodiment
of a top support arm.
[0036] FIGS. 9 and 10 are drawings of isometric and top views,
respectively, of the preferred embodiment of the duct centering
support arm with the integral spring action centering
mechanism.
[0037] FIG. 11 is a detailed view of the preferred wheel
configuration on each end of the duct centering support arm of FIG.
9.
[0038] FIGS. 12 and 13 are side and end views, respectively, of the
duct centering support arm of FIG. 9.
[0039] FIG. 14 illustrates another possible embodiment of the duct
centering support arm 30.
[0040] FIG. 15 is a front view of the draining mechanism 50 of the
present invention including deflector 51.
[0041] FIG. 16 is a side view of the deflector 51 and catch basin
60.
[0042] FIG. 17 is a side view of the deflector 51 with exemplary
dimensions.
[0043] FIG. 18 is an isometric view of the deflector 51 showing the
contours.
[0044] FIGS. 19 and 20 are an isometric view and end view,
respectively, of the catch basin 60.
[0045] FIG. 21 is an isometric view of the drainage basin.
[0046] FIG. 22 is a perspective view of an exemplary filter
modification in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0047] The present invention is described in the context of a
conventional kitchen ventilation system with an exhaust end 5 and
an air intake end 6 (FIG. 1), an electronically controlled exhaust
fan 1 at exhaust end 5, a rectangular vertical duct 2, and a
kitchen hood 3 with removable flue filters 4 at air intake end 6.
In operation, the exhaust fan 1 pulls kitchen air (including smoke
and airborne grease) into the hood 3 through flue filters 4, into
the duct 2 and out exhaust fan 1. One skilled in the art should
appreciate that the present invention can be easily adapted for use
with any similar ventilation system, including systems using
cylindrical or non-vertical ducting, without departing from the
scope and spirit of the present invention.
[0048] The kitchen ventilation degreasing system according to the
present invention includes two main components, a cleaning
mechanism 10 (described below with reference to FIGS. 2-14) with
support features, and a drainage mechanism 50 (see FIGS.
15-22).
[0049] FIG. 2 is a system illustration of the primary components of
the cleaning mechanism 10 of the kitchen ventilation degreasing
system of the present invention, as well as the support
features.
Cleaning Mechanism
[0050] Referring to FIG. 2, the cleaning mechanism 10 comprises a
water feed tube 11 connected through a sequence of
solenoid-controlled valves V1-V7 (all housed in a valve housing 13)
to multi-stage duct conduit 12 which runs the length of the
ventilation duct 2 for degreasing same (FIG. 1). In addition, hood
conduit 14 runs the length of the existing ventilation hood 3 for
degreasing it (FIG. 1). Further, a venturi injector 18 is connected
inline to the water feed 11 for injecting cleaning agents into the
water flow, as necessary, to achieve the degreasing.
[0051] The illustrated embodiment includes a two-stage duct conduit
12, including upper and lower stages 12a & 12b, and each stage
of duct conduit 12 comprises a plurality of segments screw-coupled
in series to a number of nozzle blocks 16 each having a plurality
of spray nozzles 17. Preferably, each nozzle block 16 will have 4
spray nozzles 17. FIG. 3 is a perspective illustration of the
nozzle block 16 of FIG. 2, inclusive of spray nozzles 17.
[0052] The illustrated embodiment also includes a hood conduit 14
in fluid communication with a number of swiveling hood nozzle
blocks 26 each having a plurality of spray nozzles 27. Preferably,
each swiveling hood nozzle block 26 will have two spray nozzles 27.
FIG. 5 is a front perspective illustration of the hood nozzle block
of FIG. 2, FIG. 6 is a perspective view in the overall context of
the hood 3, and FIG. 7 is a side view. The spray nozzles 27
preferably swivel about two-axes to allow adjustment upon
installation for uniform spray application inside the hood 3. This
is accomplished by rotatable couplings as shown by arrows. The
swiveling hood nozzle blocks 26 are supported within the hood 3 by
several hood conduit supports 33 (described below in more
detail).
[0053] Referring back to FIG. 2, the length of each segment of duct
conduit 12 will be directly proportional (typically equal) to the
smallest cross-sectional dimension of the duct 2. For example the
length of each segment of duct conduit 12 on a 12" by 12" duct
would be 12" long, on a 12" by 18" duct it would also be 12" long,
but on an 18" by 18" duct it would be about 18" long. In the
preferred embodiment conduit segments 12 are made of standard (i.e.
3/8 inch NPT) brass piping. However, those skilled in the art will
appreciate that the present invention can be easily adapted for use
with other materials suitable for water distribution, including but
not limited to copper and galvanized steel.
[0054] Flow of liquid (i.e. water or water containing cleaning
agents) out of the nozzles 17 of the upper or lower stages of duct
conduit 12, as well as the nozzles 27 of hood conduit 14, is
controlled by a plurality of solenoid valves V1-V7, all of which
are housed in a wall-mounted valve housing 13. In the preferred
embodiment of the present invention each solenoid valve V1-V7 is a
conventional electromechanical valve. All of the valves V1-V7 are
electrically-connected to a conventional programmable logic
controller 15 for automatic control thereby. The programmable logic
controller 15 is housed in a separate enclosure (remote from valve
housing 13) to protect the electronics and for code compliance.
[0055] The water feed tube 11 is connected to a conventional water
source (i.e. existing tap plumbing) for most kitchen ventilation
systems. In order for the spray nozzles 17, 27 to function properly
the water pressure must be a minimum of 15 PSI at each nozzle.
Those skilled in the art will recognize that this minimum required
PSI may vary depending on the type of spray nozzle used. One
skilled in the art will also understand that larger kitchen
ventilation systems may require more pressure than can be mustered
from the existing plumbing, in which case a supplemental water
pressurization system is required (any of a wide variety of
existing pumps with or without accumulator tanks will suffice).
Once the water source is activated, water flows from the water feed
tube 11 through the valves V1-V7 in valve housing 13 and into the
two-stage duct conduit 12, as well as the hood conduit 14.
[0056] A concentrated cleaning agent or solvent 70 of a type
designed to cut grease, is introduced into the system by insertion
of a feed tube 71 into the cleaning solution, and opening a check
valve 72 as shown.
[0057] In operation, the programmable controller 15 is programmed
to apply the cleaning agent 70 throughout the ventilation
degreasing system, wait a predetermined time for cleaning to occur,
and then rinse. This cycle can be repeated as desired. Each
cleaning agent then water application is preferably cascaded from
top down, upper stage of duct conduit 12a first, and then lower
stage(s) 12b to reduce pressure losses. Next, the cleaning
agent/water applications are applied through hood conduit 14 to
degrease the kitchen hood.
[0058] During the initial application of cleaning agent 70, the
programmable controller 15 opens the normally-closed input valve
V3, and opens the normally-closed diverter valve V5, thereby
diverting water through venturi injector 18. The venture injector
18 inducts cleaning agent 70 into the water flowstream which
continues into the two-stage duct conduit 12, and into conduit 14.
The controller 15 selectively opens the normally-closed staging
valves V1, V2 or V7 in order to divert water/cleaning agent into
the desired upper stage 12a, and then lower stage 12b, and then
hood conduit 14 per the cascaded operation. Spray is emitted from
the upper most nozzles 17 first, and this valve configuration is
maintained for a predetermined length of time in order to
completely wet the interior surface area 19 of the duct 2
immediately surrounding the upper most nozzles 16. After the
predetermined length of time has passed, the staging valve V1
closes and the next valve V2 opens to supply water and solvent to
the next lower stage of nozzles and so on (for as many stages as
necessary). This sequential cascading supply of water/cleaning
agent to the successive stage of nozzles 16 in a top down manner
ensures that the water and solvent in the duct conduit 12 maintains
sufficient water pressure (i.e. min 15 PSI at each nozzle) so that
the entire interior surface 19 of the duct 2 is wet down with
cleaning solution.
[0059] After the cleaning agent is applied to duct 19, valve V7 is
opened and cleaning agent is applied throughout conduit 14 to hood
3 for a predetermined length of time. The cleaning agent is here
sprayed uniformly onto the hood 3 surfaces behind the filters 4
(typically four removable filters) through swiveling hood nozzle
blocks 26 and nozzles 27. Depending on the length of the hood 3,
this spraying operation may require staging as well. To maintain
sufficient pressure at each nozzle 27, the number, spacing and
location of the nozzle swivel blocks 26 can be varied depending on
the dimensions of the hood 3 and the spray angle of the nozzles
27.
[0060] Depending on the type of cleaning agent used, the cleaning
agent is allowed to set on the interior surface 19 of duct 2 and
inside hood 3 for a predetermined length of (approximately ten
minutes or so), and the process is repeated with only water (valve
V5 closes and V6 is opened by controller 15). The programmable
controller 15 then opens and closes valves V1, V2 and V7 in the
same cascading manner, described above, to ensure complete rinsing
of the cleaning agent from the interior surface 19 of the duct 2 as
well as the interior surface of the hood 3. If desired, the
degreasing process may be assisted by using hot tap water or by
directing tap water through a water heater or super-heater (not
shown) prior to entering water feed 11.
[0061] FIG. 4 is an exploded detailed cross section of the
preferred venturi type cleaning agent injector 18 of the present
invention. This type of injector is integrated into the water feed
tube 11 as shown in FIG. 2. In operation, as water flows through
the injector 18 it is constricted inwardly of the injector chamber
73 and changes into a high velocity stream. The increased stream
velocity through the injector chamber causes a pressure
differential, creating a vacuum that sucks the cleaning agent 70
into the water flow. An electrical or mechanical valve 72 may be
installed to turn on or off addition of cleaning agents, as
necessary.
Support Features
[0062] With reference to FIG. 2, the cleaning mechanism 10 includes
three types of support components: (1) the top support arm 20, and
(2) at least one duct centering support arm 30 (two are shown); and
several hood conduit supports 33.
[0063] The top support arm 20 is secured to a supporting structure
at the exhaust end 5 (See FIG. 1) adjacent to exhaust fan 1 such
that when the duct conduit 12 is attached to top support arm 20.
The duct conduit 12 hangs vertical and is centered within the walls
of the duct 2. The top support arm 20 spans the existing duct 2
near its uppermost edge adjacent to the exhaust fan 1, and may be
fixed to the duct 2 by any suitable attaching means (i.e. bolted,
welded, etc.).
[0064] FIG. 8 illustrates one embodiment of top support arm 20. In
this embodiment top support arm 20 includes a rectangular spacer
block 21 with a center through bore 22 (alternatively, two spaced
blocks). The diameter of the center through bore 22 is
approximately equal to the outer diameter of duct conduit 12, such
that the duct conduit 12 inserted into the through bore 22 sits
securely. Once the duct conduit 12 is inserted into through bore
22, a collar 23 is secured to the duct conduit 12 immediately above
the top support arm 20 to prevent the conduit from slipping
downward. The top arm 20 further includes two symmetrical elongated
rigid struts (or brackets) 24. These struts are secured to (i.e. by
welding, bolting, etc.) the opposing vertical planes of rectangular
block 21 (sandwiching them), such that the elongated struts 24 are
oriented perpendicular to through bore 22. Both ends of each
elongated strut 24 are angled (right angle) outward, so that the
shape of top support arm 22 forms essentially an I-bar. The angled
ends 25 form a surface for securing the top support arm 22 to the
ducting 2 (i.e. by welding, bolting, etc.).
[0065] Referring back to FIG. 2, the duct centering support arms 30
are designed to ensure that duct conduit 12 remains centered and
secure within duct 2, and yet allow for heat expansion and
contraction. Depending on the length of the duct 2 and the number
of duct conduit 12 segments used, a particular ventilation system
may need more than one duct centering support arm 30. Optimally, a
duct centering support arm 30 should be attached at its center
point 35 to the conduit at every unsupported length of duct conduit
12 exceeding approximately 20 feet. Also, an additional duct
centering support arm 30 should be installed whenever there is a
change in the size or angle of duct 2. The length of the duct
centering support arm 30 is approximately equal to the width of the
interior dimension of the duct. If the duct is cylindrical in shape
then the length of the duct centering support arms is approximately
equal to the inner diameter of the cylinder. If the duct is
rectangular in shape then the length of the centering support is
approximately equal to two opposing corners. Each duct centering
support arm 30 is further comprised of lateral springs that allow
the length of the duct centering support arm 30 to increase or
decrease as the duct 2 expands and contracts with varying
temperature. In addition, each duct centering support arm 30 is
equipped with an opposing wheel mechanism 40 at each end 33.
[0066] FIGS. 9-13 collectively illustrate a preferred embodiment of
a duct centering support arm 30. Each duct centering support arm 30
is further comprised of spring arms 31 that allows the length of
the duct centering support arm 30 to increase or decrease as the
duct 2 expands and contracts with varying temperature. The duct
centering support arm 30 of this embodiment is comprised of two
essentially M-shaped symmetrical elongated rigid metal straps 36
each with two ends 33, a center point 35 and 2 distal points 37.
The ends 33 and center points 35 run parallel and adjacent to each
other for some length. The center points 35 are attached by any
suitable means (i.e. welding, bolting, etc.). The spring arms 31
allow the duct centering support arms 30 to remain in constant
contact with the interior surfaces 19 of the duct 2, thus keeping
the duct conduit 12 centered.
[0067] FIGS. 9 and 10 are isometric and top views, respectively, of
the preferred embodiment of the duct centering support arm 30 with
the integral spring action centering mechanism, and FIG. 13 is an
end view, respectively, of the duct centering support arm of FIG.
9.
[0068] In addition to the spring arms 31, each duct centering
support arm 30 is equipped with an opposing wheel mechanism 40 at
each end 33.
[0069] FIGS. 11-12 illustrate the manner of attaching the ends 33
of the two straps 36 to incorporate wheel mechanism 40. The wheel
mechanism 40 includes a horizontally attached clevis pin 41 on to
which is secured a vertical wheel 42.
[0070] With combined reference to FIGS. 9-12, the ends 33 of straps
36 are aligned and each include a through bore. Inserted between
the interior surfaces of the straps 36 are two interior flat
washers 44 aligned with the through bores. Inserted and centered
between the two interior flat washers 44 is a wheel 42. Also
aligned with the through bores are two exterior flat washers 45 on
each strap 36. A clevis pin 41 is inserted into through bore and
secures the aligned features 33, 42, 44 and 45. The clevis pin 41
is then secured by cotter pin 46. In this particular embodiment
(illustrated collectively in FIGS. 6-10), the duct centering
support arm 30 may be attached to the duct conduit 12 by any
suitable attaching means (i.e. a collared bracket).
[0071] Also, in this particular embodiment (illustrated in FIGS.
9-12), the preferred material and thickness for the duct centering
support arm is 16 gauge galvanized steel with a 2" width. Due to
its strength and flexibility, as well as its suitability for use in
conjunction with water, galvanized steel or other non-corrosive
material is the preferred material used in making the duct
centering support arms 36. The preferred material for the wheel
mechanism 40 components is zinc plated steel. However, those
skilled in the art will appreciate that there are many suitable
materials. This unique configuration of two opposing symmetrical
M-shaped straps 36, in combination with the strap dimensions and
material, forms an integral spring mechanism 31.
[0072] In operation, if the duct 2 contracts, then pressure is
exerted against end 33 which causes straps 36 to bend at distal
points 37 to accommodate the contraction. As the duct 2 expands,
pressure against ends 33 is decreased and the straps 36 flex at
distal points 37. This continuously centers and supports duct
conduit 12 within duct 2.
[0073] In operation the duct centering support arms 30 are secured
to the duct conduit 12 prior to installing the duct conduit 12 into
the duct 2. As the duct conduit 12 is lowered into the duct 2 from
the exhaust end of the ventilation system, the wheels 42 of the
attached duct centering support arms 30 roll along the interior
surface 19 of duct 2. This ensures that the duct conduit 12 remains
centered within the duct 2 as it is being installed.
[0074] An alternative embodiment of duct centering support arm 130
is illustrated in FIG. 14. A threaded cross fitting 137 connects
the duct conduit 12 to the duct centering support arm 130. The duct
conduit 12 is inserted through and secured vertically in the cross
fitting 137. The duct centering support arm 130 is comprised of two
hollow cylindrical beams 136. Each beam 136 has a threaded end 138
and a wheeled end 133 with a wheel mechanism 140. The threaded end
138 of each beam is threaded into the threaded cross fitting 137
such that the wheel 142 on the opposite end 133 aligns vertically.
The beam 136 at the wheeled-end 133 is cut with two opposing
channels 139 of some length to accommodate vertical wheel 142. A
fixed pin 143, extending across the horizontal diameter of beam 136
at each end 133, acts as an axle for wheel 142. In order to
accommodate a spring mechanism 131, hollow beam 136 may be further
comprised of two telescoping hollow beams 136a (including the
threaded end 138) and 136b (including in the wheeled end 133). A
spring (not shown) within beam 136a, allows the beam to telescope
out and in depending on the pressure exerted by the duct 2 against
the ends 133.
[0075] Inside the hood 3, conduit supports 33 are required to
secure hood conduit 14 to the hood 3. The hood conduit supports 33
are best shown in FIG. 5. A clamping device including clamping
sections 150 and 151 is bolted around conduit 14 to secure the
conduit 14 in correct position. Clamp section 151 connects to a rod
152 (which may be threaded or otherwise adjustable in length),
which is in turn connected to a base plate 153. Baseplate 153 is
secured to hood 3 by welding or by bolts.
Draining Mechanism
[0076] Referring to FIGS. 15-18, the draining mechanism 50 of the
preferred embodiment of the present invention includes a deflector
51 and a catch basin 60 which empties through a drain pipe 52 to a
removal vessel (not shown). Both the deflector 51 and catch basin
60 may be retrofit to the existing ventilation system at the intake
end 6 (as depicted in FIG. 1).
[0077] FIG. 15 is a front view of the draining mechanism 50 of the
present invention including deflector 51, and FIG. 16 is a side
view of deflector 51 with a catch basin 60.
[0078] Deflector 51 is formed from an essentially rectangular sheet
of metal with an upper portion 53 that hooks over the existing
removable filter 58 at the intake end 6, thereby anchoring the
deflector 51 inside the ventilation system. The deflector 51 is
formed with a louvered central section that angles inward and away
from the filters 58. The deflector 51 prevents cleaning agent,
water and/or debris from escaping outward through the filters 58,
and ensures that it drains downward into the existing ventilation
system gutter 67.
[0079] In the preferred embodiment of the present invention the
deflector 51 is made of a single piece of stainless steel bent, cut
and/or molded to the desired shape. However, it will be obvious to
one skilled in the art that the deflector 51 may be constructed
with other appropriate materials and/or with multiple attached
pieces. As seen in FIG. 15, a plurality of horizontal cuts may be
made in the metal with the upper edge of the cuts pushed inward
some distance, forming a plurality of horizontal louvers 57.
[0080] FIG. 17 is a side view of the deflector 51 with exemplary
dimensions, and FIG. 18 is a perspective view to show the contours.
The deflector 51 is attached to the hood 3 at the air intake end 6
(See FIGS. 1 and 16) of the ventilation system behind the flue
filters 58. In the preferred embodiment deflector 51 is attached to
hood 3 such that it is oriented at an approximate 45 degree angle
to the entrance of duct 2. Additionally, the deflector 51 is of
such a size that when attached to hood 3 it is capable of catching
all liquid-run off from the duct 2.
[0081] FIGS. 19 and 20 are a perspective view and end view,
respectively, of the catch basin 60 which is attached (by welding
or the like) beneath the existing gutter 67 of the ventilation
system at the intake end 6 (as depicted in FIG. 16). The catch
basin 60 is a simple rectangular receptacle with drainage aperture
that empties through a drain pipe 52 attached thereto to a removal
vessel (not shown). If necessary, the existing ventilation system
gutter 67 must be perforated to empty into the catch basin 60.
[0082] In operation of the above-described draining mechanism 50,
liquid run-off from the operation of the kitchen ventilation
degreasing system 10 drips from the duct 2 onto the deflector 51.
The slats 57 are angled to allow air flow into the duct 2 (for
proper ventilation), but to prevent liquid from escaping out.
Run-off continues down into the existing gutter 67 where it empties
into catch basin 60 and outward through drain pipe 52. No spray or
run-off is permitted to escape into the kitchen.
[0083] Referring back to FIG. 2, the controller 15 allows the
cleaning system 10 to drain as well, closing valve V3 and opening
valves V1, V2, V4 and V7 to a drainage conduit. The internal check
valve to the cleaning solution is also closed to prevent
backwash.
[0084] The above-described system also self-monitors its own
effectiveness with a turbidity sensor 90 incorporated in the
drainage mechanism 50 to monitor the amount of residue in the
draining run-off. A turbidity sensor 90 may be incorporated as
shown inline in the drainage tube or other appropriate drainage
point, and is coupled to the microcontroller 15 to provide feedback
of the relative amount of suspended solids in the run-off. A
variety of commercially-available turbidity sensors are presently
used in other contexts such as dishwasher and washing control, and
suitable sensors are available from Honeywell. The turbidity sensor
90 is here used to determine whether the interior surfaces of the
ventilation system are adequately clean by examining the
cleanliness of the rinse water. If not, the system 100 simply
repeats the above-described process until satisfactory.
[0085] An alternative drainage mechanism is shown in FIGS. 21 and
22. FIG. 21 is an isometric view of an alternate drainage basin 80
which may be more suitable for certain existing kitchen hoods 3.
Some hoods 3 are equipped with a grease channel 67 for running off
of the grease into an existing grease cup (not shown), which is
typically suspended beneath the grease channel 67 by posts which
are inserted down into keyholes in the grease cup. The drainage
basin 80 is designed to replace the existing grease cup at the same
location and is provided with similar hanger keyholes 81 for
slidable insertion onto the existing posts. The drainage basin 80
is fabricated as a stainless steel enclosure that channels the
grease and runoff down toward a discharge pipe 83. A grease baffle
82 is welded in advance of the discharge pipe 83 to prevent grease
from the cooking operation (taking place below) from directly
entering the discharge pipe 83. If the existing hood incorporates
conventional filters 4, these existing filters 4 can be modified to
prevent spray or runoff from the cleaning operation from affecting
the cooking operation.
[0086] FIG. 22 is a perspective view of an exemplary filter
modification in accordance with the present invention. Typically,
four filters 4 are seated in frames in the hood 3, and a small void
exists between adjacent filters. A stainless steel plate 90 is
attached lengthwise along one side of each filter 4 to span this
void. The plate 90 is located behind the filters 4 and will not
affect seating in the frame, and yet it covers the void to prevent
effluent from leaking between adjacent filters 4. Note also that
existing filters 4 are equipped with a series of holes 91 for flow
there through, and with the foregoing modification the diameter of
these holes 91 should be increased to accommodate the increased
flow. Thus, during the cleaning operation the effluent will flow
across the inside face of the filters 4 into the grease channel 67
(FIG. 21), down the slope of the grease channel 67 and into the
drainage basin 80, and out through the discharge pipe 83 where it
can be directed into an existing grease trap or otherwise, as
desired.
[0087] It should now be apparent that the foregoing device excels
at automatically degreasing the interior surfaces of kitchen
ventilation systems both safely and economically without need for
any hand held and directed equipment. The device can be permanently
installed on-site, either as original equipment with installation
of the ducting or retrofit into pre-existing systems, and can be
connected directly to a pre-existing water source to operate from
existing pressure, thereby avoiding the need for installing an
expensive water pressurization system.
[0088] Having now fully set forth the preferred embodiment and
certain modifications of the concept underlying the present
invention, various other embodiments as well as certain variations
and modifications of the embodiments herein shown and described
will obviously occur to those skilled in the art upon becoming
familiar with said underlying concept. It is to be understood,
therefore, that the invention may be practiced otherwise than as
specifically set forth in the appended claims.
* * * * *