U.S. patent application number 11/214281 was filed with the patent office on 2006-06-08 for liquid detergent dispensing system for automatic washer.
Invention is credited to Roger E. Kinnetz.
Application Number | 20060117811 11/214281 |
Document ID | / |
Family ID | 36572678 |
Filed Date | 2006-06-08 |
United States Patent
Application |
20060117811 |
Kind Code |
A1 |
Kinnetz; Roger E. |
June 8, 2006 |
Liquid detergent dispensing system for automatic washer
Abstract
A liquid laundry detergent dispenser for an automatic washing
machine employs a reservoir that holds a quantity of the detergent
sufficient for numerous wash cycles. An air/fluid chamber fills
through a check valve from the base of the reservoir. To commence a
dispense cycle, a timer circuit is actuated to run an air pump that
supplies air under pressure through an air hose to the air/fluid
chamber, and this displaces the detergent from the chamber and
through a detergent dispense hose into the tub or drum of the
washing machine. At the end of the dispense cycle, a bleed valve
opens to relieve pressure on the air hose and the air/fluid
chamber. The automatic detergent dispenser can be attached to
existing washers or built in. A multiple arrangement can be used
with a bank of washers at a commercial laundry.
Inventors: |
Kinnetz; Roger E.;
(Baldwinsville, NY) |
Correspondence
Address: |
BERNHARD P. MOLLDREM, JR.
224 HARRISON STREET
SUITE 200
SYRACUSE
NY
13202
US
|
Family ID: |
36572678 |
Appl. No.: |
11/214281 |
Filed: |
August 29, 2005 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
60633621 |
Dec 6, 2004 |
|
|
|
Current U.S.
Class: |
68/17R ;
8/158 |
Current CPC
Class: |
D06F 39/022 20130101;
D06F 2105/58 20200201; D06F 33/37 20200201 |
Class at
Publication: |
068/017.00R ;
008/158 |
International
Class: |
D06F 35/00 20060101
D06F035/00 |
Claims
1. An automatic liquid detergent dispensing arrangement for
dispensing a controlled amount of detergent during a dispense cycle
into an automatic washing machine, comprising a reservoir tank for
storing a quantity of liquid detergent sufficient for a
multiplicity of wash cycles of the automatic washing machine; an
air/fluid chamber adapted for holding an amount of detergent
sufficient for at least one detergent dispense cycle; one-way valve
means for admitting detergent from said reservoir tank into said
air/fluid chamber; a detergent discharge hose extending from the
air/fluid chamber to a discharge means for discharging the liquid
detergent from the air/fluid chamber into the washing machine; air
pump means for applying air under pressure to the air/fluid chamber
so as to drive the liquid detergent in said air-fluid chamber
through said discharge hose; and control means coupled to said air
pump means for selectively energizing the air pump means, including
a switch for initiating a detergent discharge cycle.
2. An automatic liquid detergent dispensing arrangement according
to claim 1 wherein said control means also includes a selector for
selecting the volume of detergent to be discharged during such
cycle.
3. An automatic liquid detergent dispensing arrangement according
to claim 2 wherein said control means includes a variable timer
circuit having a manually adjustable arrangement for selecting a
length of time of operation of said air pump means during said
detergent discharge cycle.
4. An automatic liquid detergent dispensing arrangement according
to claim 3 wherein said variable timer circuit includes an RC
discharge circuit including a variable resistor serving as said
manually adjustable arrangement.
5. An automatic liquid detergent dispensing arrangement according
to claim 1 wherein said air pump means includes a low volume air
pump capable of delivering about 2 liters/minute of air at about 5
to 10 psi.
6. An automatic liquid detergent dispensing arrangement according
to claim 1 wherein said air/fluid chamber is disposed within said
reservoir tank at a bottom thereof.
7. An automatic liquid detergent dispensing arrangement according
to claim 1 wherein said an air hose extends from said air pump
means to said captive air/fluid chamber, and further comprising a
solenoid valve on said air hose which is normally open to vent said
air hose when said air pump means is not actuated, and which closes
to shut off venting of said air hose when the air pump means is
actuated.
8. An automatic liquid detergent dispensing arrangement according
to claim 1 wherein said reservoir tank includes a cylinder oriented
vertically and having a capacity sufficient to hold at least one
gallon of said liquid detergent.
9. An automatic liquid detergent dispensing arrangement according
to claim 1 wherein said one way valve means includes a check valve
disposed at a lower end of said captive air/fluid chamber and
having a first port to receive said fluid detergent from said tank
reservoir, a second port onto which said discharge hose is
attached, and a third port that connects with said air/fluid
chamber for filling said chamber after a detergent discharge cycle
and for transmitting said detergent from the air/fluid chamber to
said discharge hose.
10. An automatic liquid detergent dispensing arrangement according
to claim 1 wherein said reservoir tank is situated within a cabinet
of said washing machine.
11. An automatic liquid detergent dispensing arrangement according
to claim 6 wherein said reservoir tank is mounted onto a back side
of said washing machine, and said detergent discharge hose passes
through a port on a back side of a cabinet of said washing
machine.
12. An automatic liquid detergent dispensing arrangement according
to claim 11 wherein said discharge means includes a portion of said
hose that extends over a tub of said washing machine.
13. An automatic liquid detergent dispensing arrangement according
to claim 6 wherein said reservoir tank is mounted onto a back side
of said washing machine, and said detergent discharge hose passes
outside a cabinet of said washing machine, and said discharge means
includes a flat flexible hose portion that extends under a lid of
said washing machine.
14. An automatic liquid detergent dispensing arrangement according
to claim 13 further comprising a cosmetic cover disposed over said
flat flexible hose portion.
15. An automatic liquid detergent dispensing arrangement according
to claim 1 wherein said one-way valve means admits said detergent
from said reservoir tank into said air/fluid chamber by gravity
flow.
16. An automatic liquid detergent dispensing arrangement according
to claim 1 comprising a sensor in said tank for detecting low
detergent level, and an indicator on said control means actuated by
said sensor.
17. An automatic liquid detergent dispensing arrangement for use
with a plurality of automatic washing machines and adapted for
dispensing a controlled amount of detergent during a dispense cycle
into a selected one of said automatic washing machines, comprising
a reservoir tank for storing a quantity of liquid detergent
sufficient for a multiplicity of wash cycles of the automatic
washing machines; a plurality of air/fluid chambers, each adapted
for holding an amount of detergent sufficient for at least one
detergent dispense cycle; a plurality of one-way valve means, each
associated with a respective one of said air/fluid chambers, for
admitting detergent from said reservoir tank into the associated
captive air/fluid chamber by gravity flow; a plurality of detergent
discharge hose, each extending from a respective one of said
air/fluid chambers to a discharge means for dispensing the liquid
detergent from the air/fluid chamber into a respective one of said
washing machines; air pump means for selectively pressurizing one
or another of said air/fluid chambers with air under pressure so as
to drive the liquid detergent in said air-fluid chambers through
the associated discharge hose; and control means coupled to said
air pump means for selectively energizing the air pump means,
including means for initiating a detergent discharge cycle.
18. An automatic liquid detergent dispensing arrangement according
to claim 17, said control means further comprising a selector for
selecting the volume of detergent to be discharged during such
cycle.
19. A process of automatically injecting a measured amount of
liquid detergent into an automatic washing machine including
filling a detergent tank with a supply of liquid detergent
sufficient for a multiplicity of wash cycles; permitting gravity
flow of the liquid detergent from said tank into an air/fluid
chamber to fill said chamber; supplying compressed air to said
air/fluid chamber during a detergent dispense cycle, such that the
compressed air drives the detergent from said air/fluid chamber
through a detergent dispense hose into a wash chamber of said
washing machine; and relieving air pressure in said air/fluid
chamber after a dispense cycle to permit the air/fluid chamber to
refill with said detergent.
20. A process according to claim 19, wherein said supplying of
compressed air includes powering an air pump for a timed interval.
Description
[0001] Applicant claims priority of Provisional Application
60/633,321, Dec. 6, 2004. The disclosure of such provisional
application is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] This invention is directed to the automatic washing
machines, e.g., for clothes washing and laundry, although the
principles could be applied to dishwashers and other automated
washing or cleansing systems. The invention is more particularly
concerned with systems and devices for automatically injecting a
measured amount of detergent and moving it from a storage tank or
container into the washing machine.
[0003] Automatic washing machines have been used commercially and
in homes for many decades. In each case, the user has to measure
and dispense a quantity of detergent into the machine at the
commencement of a wash cycle. There is always human error in
administering the detergent to the machine, and often too much
detergent is dispensed. Further, it is inconvenient for the user to
have to measure and pour in the detergent. Additionally, there is a
need to keep bottles of laundry detergent on hand, and these have
to be stored somewhere.
[0004] Detergent manufacturers have devised many improved methods
of pouring and measuring detergent from the respective container.
Also, washing machine manufacturers have introduced built-in
dispensers into some washing machines. However, these only hold
enough detergent for a single wash cycle.
[0005] When using liquid detergent for a wash cycle, it is
important to look carefully at the detergent manufacturer's
instruction and marking(s). Different amounts are recommended for
different size washer loads. Typically, the cap of the detergent
container is marked for full and partial loads, but many people
find it difficult to fill the cap up to a partial level. More
typically, in the case of a medium or light load, the person will
simply fill the cap to the "full load" level, even when that is not
necessary, e.g., for a medium or light load, resulting in wasted
detergent, and creating an environmental burden by injecting
unnecessary amounts of the detergent into the fluid waste stream.
Also, for most persons, guesswork is involved in the measuring of
the detergent. It is desired to create an automated system which
avoids any need for human measuring of the amount of detergent, and
avoids need for handling or transfer of detergent. It is also
desired for a system to match the amount of detergent used to the
size of the load of laundry (or other items to be washed).
OBJECTS AND SUMMARY OF THE INVENTION
[0006] Accordingly, it is an object of this invention to provide a
simple and cost effective system for automatically dispensing
liquid laundry detergent directly into a washing machine, that
avoids the drawbacks of the prior art.
[0007] It is another object to provide a system which dispenses
detergent from a bulk tank or container into the drum or tub, i.e.,
the wash chamber of the washing machine, without need for the user
to pour detergent into a measuring device.
[0008] It is a further object to provide a system that permits the
amount of detergent injected to be adjustable so that the amount of
detergent will match the size of the load.
[0009] The general purpose and principle behind the invention, as
will be described below in greater detail, involves storing the
liquid detergent in large quantities in a tank or reservoir, which
can be attached onto the washing machine or built-in and located
inside the cabinet. A low pressure air pump system or a source of
low pressure compressed air (e.g., 5 to 10 psi) is employed to
transport the liquid detergent from the reservoir into the
washer.
[0010] According to one aspect of this invention, an automatic
liquid detergent dispensing arrangement dispenses a controlled
amount of detergent, during a dispense cycle, into an automatic
washing machine. A reservoir or tank, which can either be mounted
on the back side of the machine or situated in an available space
inside the cabinet, stores a quantity of liquid detergent
sufficient for a multiplicity of wash cycles of the automatic
washing machine. A positive displacement air/fluid chamber either
is situated within the reservoir at the bottom, or else is
connected to the lower part of the reservoir. This air/fluid
chamber has capacity to hold an amount of detergent sufficient for
at least one detergent dispense cycle. A one-way check valve admits
detergent by gravity flow from the reservoir tank into the captive
air/fluid chamber. A detergent discharge or dispense hose extends
from the captive air/fluid chamber to a discharge point for
dispensing the liquid detergent from the air/fluid chamber into the
washing machine. This can be just above the drum or tub of the
washing machine. An air pump is energized for pressurizing the
captive air/fluid chamber with sufficient air pressure (e.g., 5 to
10 psi) so as to drive the liquid detergent from the captive
air-fluid chamber through said discharge hose. A control circuit is
coupled to the air pump for selectively energizing the air pump
means, e.g., for a period of time after a switch is pushed to
initiate the detergent dispense cycle or discharge cycle. A knob or
other selector is provided so the user can select the volume of
detergent to be discharged during this cycle. Preferably, the
control circuitry employs a variable timer circuit with a manual
adjustment for selecting a length of operation of the air pump
during the detergent dispense cycle. This can be an RC discharge
timer circuit including a variable resistor serving as manual
adjustment. The air pump can operate at low voltage DC, e.g., 6 to
12 volts, and is capable of delivering about 2 liters/minute of air
at 5 to 10 psi. The air pump can be powered from a battery source
or from a small 12-volt transformer-rectifier, which can plug into
a standard wall outlet.
[0011] Preferably, a small, flexible air hose extends from the air
pump to the air/fluid chamber, and a solenoid bleed valve is
present on the air hose for bleeding or venting pressure when the
dispense cycle ends. The solenoid valve is normally open to vent
the air hose when the air pump is not being energized, but closes
to shut off venting when the air pump means is pumping, so that the
pressure is directed to the captive air/fluid chamber.
[0012] The one way valve can be a check valve, e.g., ball type or
flap type, disposed at a lower end of the captive air/fluid
chamber. A first port receives fluid detergent from the tank or
reservoir, a second port connects to the discharge hose, and a
third port connects with the air/fluid chamber for filling said
chamber after a detergent dispense cycle and for transmitting the
detergent from the captive air/fluid chamber, during the dispense
cycle, through the discharge hose and into the washing machine drum
or tub. In the case of a dishwasher, for example, the wash chamber
would not be in the form of a drum or tub, but the detergent
dispenser would operate on the same principle.
[0013] In an after-market or add-on version, the reservoir tank can
be mounted onto a back panel of the cabinet of the washing machine,
and the detergent discharge hose passes through a port on a back
panel of the cabinet. A rubber grommet may be used to hold the hose
in this opening. An end portion of the hose extends over the drum
or tub. In an alternative after-market version, the reservoir tank
is mounted onto a back side of the washing machine, as before, but
the detergent discharge hose passes outside a cabinet and over the
back or one side of washing machine. There is a flat flexible hose
portion that extends under the lid of said washing machine, and
allows the detergent to be discharged into the drum or tub.
[0014] For a front-loading washer, the detergent dispensing hose
can be inserted into the detergent receptacle of the unit, rather
than injecting the liquid detergent directly into the tub or
drum.
[0015] In a preferred embodiment, the reservoir tank can take the
form of a tall vertical cylinder e.g., a tube, which can have a
nominal diameter of about four inches. This provides sufficient
capacity to hold at least two gallons of liquid detergent. In this
case, the one way valve can take the form of a ball-type check
valve disposed at the bottom of the captive air/fluid chamber. The
check valve has a first port to receive fluid detergent from the
tank or reservoir, a second port onto which the detergent discharge
hose is attached, and a third port that connects with the air/fluid
chamber for filling the chamber, e.g., by gravity feed, after a
detergent discharge cycle. The check valve transmits the detergent
from the air/fluid chamber to the detergent discharge or dispense
hose during the dispense cycle.
[0016] In a built-in version, the cylindrical reservoir tank can be
situated within washing machine cabinet in an available space,
e.g., at a corner. In an after-market or add-on version, the
cylindrical reservoir tank can be strapped onto the back panel of
the washing machine, using bungee cords and/or cable ties, for
example. There are normally holes or openings in the back panel
which are normally used only during shipping of the washing
machine, and these can be used to accept the strapping. There is
typically an existing hole on the back panel which can be used for
inserting the detergent hose, but if not it is a simple matter to
drill or bore a hole of about 1/1 inch diameter for that purpose.
The captive air/fluid chamber may be situated within the
cylindrical tank at the bottom. Alternatively, e.g., in a built-in
version, the tank may be connected by a tube or hose to the check
valve of the captive air/fluid chamber which may be positioned at a
convenient space within the machine.
[0017] Rather than a tubular cylindrical tank, the reservoir could
be oblong or cuboid in shape.
[0018] A commercial laundry version of the automatic liquid
detergent dispensing arrangement allows the detergent to be
dispensed automatically to any of a number of automatic washing
machines. The principle is the same as discussed previously for
dispensing a controlled amount of detergent during a dispense
cycle, with the detergent going into a selected one of the washing
machines. Here, a large reservoir tank stores a quantity of liquid
detergent sufficient for a multiplicity of wash cycles for an
entire bank of automatic washing machines. For each of the washing
machines, there is an associated captive air/fluid chamber, which
operate on the same principle as the ones discussed before. Each of
these chambers is adapted for holding an amount of detergent
sufficient for at least one detergent dispense cycle, and each has
an associated one-way valve that admits detergent from the
reservoir tank, e.g., by gravity flow. For each washing machine
there is an associated detergent discharge hose, each extending
from a respective one of said captive air/fluid chambers to the
washing machine for discharging a charge of liquid detergent from
the captive air/fluid chamber into the washing machine. There is
also an air pump or pumps for selectively pressurizing one or
another of the captive air/fluid chambers to drive the liquid
detergent in the respective captive air-fluid chambers through the
associated discharge hose. A control circuit, which can have a
panel or mechanism on each of the washing machines, is coupled to
air pump or pumps to control the energizing the air pump(s). This
can include a provision for initiating a detergent discharge cycle,
and a timer to limit the amount of air provided by the pump to the
particular chamber. The period of the timer can be adjusted
(manually or automatically) so that the proper amount of detergent
is dispensed for the load of laundry to be washed.
[0019] The above and many other objects, features, and advantages
of this invention will present themselves to persons skilled in
this art from the ensuing description of preferred embodiments of
this invention, as described with reference to the accompanying
Drawing.
BRIEF DESCRIPTION OF THE DRAWING
[0020] FIG. 1 is a front perspective view of a top loading clothes
washing machine on which is mounted a liquid detergent dispensing
device according to an embodiment of this invention.
[0021] FIG. 2 is a rear view of the washing machine with the
detergent dispensing device of this embodiment.
[0022] FIG. 3 is a front perspective view of a washing machine
showing a second embodiment of this invention.
[0023] FIG. 4 is a rear view of the washing machine showing this
second embodiment.
[0024] FIG. 5 is a schematic elevation of a positive displacement
chamber and one-way fluid valve assembly which can be employed as
components of the embodiments of the invention.
[0025] FIG. 6 is a schematic view showing a reservoir, positive
displacement chamber assembly, and associated tubes and hosing, air
pump, solenoid bleed valve, and control components, according to an
embodiment of the invention.
[0026] FIG. 7 is a circuit schematic diagram of timer and
associated components of an embodiment of this invention.
[0027] FIG. 8 is a schematic view illustrating an embodiment of the
invention configured for multiple-washing machine use.
[0028] FIG. 9 is a front view of the control module employed in
this invention.
[0029] FIG. 10 is a perspective view of an alternative
embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)
[0030] With reference to the Drawing, FIG. 1 shows an embodiment of
the present invention in conjunction with a top-loading clothes
washing machine 10. It should be understood that this is an example
of one practical application, and that the liquid detergent
dispensing arrangement of this invention could be employed with
other automatic washing devices, e.g., a front-loading clothes
washer, a dish washer, etc. FIG. 2 shows the same arrangement from
the rear of the washer 10.
[0031] Here, the washing machine 10 has a cabinet or housing 12, in
which there is a tub or drum in which the clothes undergo wash,
rinse, and spin cycles. A mechanism 16 for rotating and oscillating
the drum 14 and any associated clothes agitator (not shown) is
represented schematically. A console or control panel 18 is
situated at the back of the top deck of the cabinet, behind a lid
or cover 20. The lid 20 is hinged or pivoted at the back so it can
be lifted for access the drum 14.
[0032] In this embodiment, which concerns an after-market
arrangement, the add-on dispenser mechanism or automated liquid
detergent injection system 22 is mounted externally on the back of
the cabinet or housing 12. There is a reservoir or tank 24 in the
form of a cylinder of four inches diameter and nominally forty-two
inches high. The tank 24 has a capacity of two gallons or more, and
holds enough detergent to last for a few dozen wash cycles.
Detergent may be added by pouring it into the top of the
cylindrical reservoir or tank, and a cover or closure may be
provided to fit the top end of the reservoir or tank.
[0033] A positive displacement chamber and check valve arrangement
26 is situated within the reservoir 24 and at the base or lower end
thereof. The positive displacement chamber arrangement 26 fills
with detergent by gravity feed through a check valve, which is
discussed in detail later. In this embodiment, the positive
displacement chamber arrangement 26 is situated within the
cylindrical tank or reservoir, but in other embodiments, the
arrangement 26 can be located elsewhere, with a tube or conduit
supplying the detergent from the reservoir 24.
[0034] A pump module 28 is mounted on the back of the washer
cabinet 12, and includes a low voltage air pump that supplies air
through a small-diameter air hose 30 to the positive displacement
chamber arrangement 26 to push the detergent from there, through a
detergent dispense hose 32 or detergent discharge hose. In this
embodiment, the hose 32 fits through a pre-existing opening 34 in
the back of the washing machine, and extends to a point over the
tub or drum 14. The pump module 28 is also coupled through a
multiple conductor electrical wiring harness or cable 37 to a
control module 36 that is mounted on a convenient location on the
front of the console panel 18.
[0035] As shown in more detail in FIG. 9, the control module has a
start button 38 which is pushed to commence a detergent dispense
cycle, and an volume adjustment knob 40 which is rotated by the
user to adjust the amount of detergent dispensed during a cycle,
here marked with "light", "medium", or "heavy" corresponding to the
size of the laundry load to be washed. The knob 40 adjusts a
variable resistor 140 (shown in ghost) within the module 36.
[0036] As shown in more detail in FIG. 2, the reservoir or tank 24
is affixed onto the back panel of the washing machine 10, using
some of the numerous holes or apertures that are present. These
holes 42 are typically used for attaching protective pads during
shipping of the washing machine, but are not used once the machine
is installed. One of these is the hole 34 that is situated just
above the level of the top of the drum 14, and this one is selected
for insertion of the hose 32. For securing the cylindrical tank 24,
straps 44 pass around the tank and through selected ones of these
openings 42, 42. The straps 44 can take the form of wires, bungee
cords, cable ties, or other sufficiently strong strapping material.
Also shown on the back of the washer are its water drain tube and
an electrical cord, which are not numbered. Typically, a clearance
of four inches or more between the washing machine 10 and the wall
is needed for the hot and cold water hoses, electrical cord, and
drain hose, and this same clearance is sufficient for the
cylindrical tank 24 plus other parts of the detergent dispensing
arrangement 22.
[0037] Another embodiment of the invention is illustrated in FIGS.
3 and 4, in which the elements of a detergent dispensing
arrangement 122 are built into the cabinet of the washing machine.
Here, the elements that are the same as used in the first
embodiment are identified with the same reference numbers. The tank
or reservoir 24, which here is in the form of a cylinder of about
four inches in diameter and forty-two inches in height, is
installed within the cabinet 12 at one corner. A detergent fill
port 17 is connected with the tank 24, and detergent is poured in
here rather than pouring the liquid detergent into the tank or
reservoir directly. Also in this embodiment the positive
displacement chamber arrangement 26 is situated within the cabinet
12 but outside the reservoir, and is connected by means of a fill
tube 27 to the base or bottom of the reservoir 24. The pump module
28 is also located near the positive displacement chamber
arrangement. The air hose 30 extends within the cabinet 12 from the
module 28 to the top of the positive displacement chamber
arrangement 26, and the detergent dispensing hose 32 extends from
the latter, within the cabinet 12 to a dispensing point located
above the drum or tub 14. Both these hoses loop upwards above the
level of maximum fill of the reservoir 24, so as to avoid unwanted
siphoning of the liquid detergent between dispense cycles. The
wiring harness or cable 37 is also shown extending from the pump
module 28, in this case to a control module located within the
console panel 18. Here a single control knob 136 is shown which
combines the functions of the switch 38 and knob 40. The knob 136
can be turned to adjust the amount of detergent dispensed, and can
be depressed to start the dispense cycle.
[0038] FIG. 5 shows details of the positive displacement chamber
arrangement 26, which includes a holding chamber and a fluid valve
assembly 26. In this preferred embodiment, there is a detergent
holding chamber 50, which has an inside diameter of about two and
one-half inches and a height of about three inches, giving the
chamber 50 a capacity sufficient for holding about eight fluid
ounces. At a lower end of the chamber 50 is a threaded neck 52 to
which a flow control valve assembly 54 is attached by means of
mating female threads. At the mid level of the assembly 54 is a
check valve 56 arranged for admitting flow of the liquid detergent
in the upward direction. Below the check valve is an inlet port 58
to admit the liquid detergent by gravity flow from the tank or
reservoir 24. Above the check valve 56 is an outlet port 60 that
connects to the detergent dispensing hose 32. The air hose 30
connects to an air hose fitting 62 at the top of the chamber 50.
Another optional check valve 156 can be located in the hose 32 to
block reverse flow and keep the hose 32 primed for the next use.
This additional check valve 156 can be installed in the discharge
hose 32 at the catptive fluid/air chamber 26 or more preferably at
the distal end of the hose. This keeps the hose full and keeps the
detergent in the hose from draining into the washer after the end
of a detergent dispense cycle.
[0039] The assembly of FIG. 5 operates generally as follows.
Normally, i.e., between dispense cycles, there is a neutral
pressure in the air hose 30, so the chamber 50 vents to the
atmosphere, and the liquid detergent can flow past the check valve
56 into the chamber 50 until the chamber is full. At the
appropriate time during a wash cycle, the pump module 28 applies
air under pressure via the hose 30 into the chamber 50, and this
closes the check valve and displaces the detergent within the
chamber. The liquid detergent then proceeds up through the
dispensing hose 32 and into the tub or drum 14 of the washing
machine. After a period of time, the pump module 28 stops pumping
air, and then the pressure in the air hose 30 is relieved. This
causes flow of the detergent to cease up through the dispensing
hose, and allows the chamber 50 to begin to refill, by gravity flow
from the reservoir 24. In this embodiment, the length of time that
the pump module 28 is energized to supply air under pressure is
adjusted for controlling the amount of detergent dispensed.
However, other embodiments could control other parameters to adjust
the amount of detergent dispensed.
[0040] In the preferred arrangement as shown in FIG. 5, the air
hose 30 is favorably a quarter-inch diameter vinyl tubing, and the
detergent dispense hose 32 is half-inch diameter vinyl tubing. The
check valve 56 in this embodiment is a ball-type check valve, with
tubular housing made of polypropylene, a ball guide formed of
acetal, and the ball being made of a suitable thermoplastic. Other
check valve constructions could also serve this function, e.g., a
flap valve.
[0041] FIG. 6 illustrates details of the embodiment of FIGS. 1 and
2, in which the positive displacement chamber assembly 26 is
situated within the cylindrical reservoir or tank 24 and at the
base of bottom thereof. Also shown here, the pump module 28 is
shown in more detail. The module 28 includes a small, low-volume
6-volt to 12-volt DC powered air pump 66, with a volume flow of
about two liters per minute at a pressure of about 5 to 10 psi. The
pump 66 can be energized by means of a variable timer for periods
from about ten seconds to about thirty seconds to control the
amount of detergent for small to full loads.
[0042] A solenoid bleed valve 68 is connected to the air hose 30.
The bleed valve 68 closes when the air pump 66 is energized so that
the air under pressure is directed to the chamber 50. The bleed
valve 68 opens when the pump cycle ends to relieve pressure from
the air hose 30 and from the chamber 50, so that the chamber 50 is
allowed to refill from the reservoir 24 through the check valve
56.
[0043] A printed circuit board 70 carries the necessary control
electronics, and a diaphragm pressure switch 72, communicating via
a pressure sensor tube 64 with the base of the reservoir 24, turns
on when a low pressure is detected, indicating the level of the
detergent in the reservoir 24 is below a refill level.
[0044] FIG. 7 illustrates schematically the general circuitry
employed for controlling the dispensing of detergent according to
the above-described embodiments. The pump module 28 is generally
illustrated, and this schematic also shows the multi-conductor
harness or cable 37 connecting the control module 36 to an
eight-pin connector T2 on the pump module. There is a power socket
76 for accepting a connector (not shown) from a suitable 12-volt
power supply, and providing DC power to an RC variable timer
circuit 74. In the latter, a timing capacitor C1, nominally about
220 microfarads capacity, is disposed in series with potentiometer
or variable resistance 140 (e.g., 50 kilohms), with the variable
resistance 140 being situated in the control module 36 and having a
stem that is rotated by the knob 40 (shown in FIG. 9). The timing
capacitor C1 charges up when the start switch 38 is depressed, and
the high voltage on this capacitor turns on a timing transistor Q1,
which in turn turns on a transistor Q2, which then draws current
through the coil of a relay R1. This relay R1 closes and supplies
current to the motor of the air pump 66 and to the solenoid of the
bleed valve 68. The capacitor C1 gradually discharges through the
variable resistance 140, and when its voltage falls below a
threshold for the transistor Q1, the transistors Q1 and Q2 shut
off, terminating current through the relay coil, and shutting off
the pump 66 and bleed valve 68. As also shown here, the pressure
switch 72 is arranged to open upon detecting a low level, which
turns off an indicator LED D1 on the control module 36. This LED D!
Is ont to indicate sufficient detergent is present in the tank 24,
and goes off to indicate a refill is needed. Alternatively, the LED
D1 could be configured to be normally off and would come on to
indicate a low level of detergent. The closed condition of the
relay R1 provides current to a run indicator LED D2 on the module
36, indicating that a detergent dispense cycle is taking place.
[0045] While the timing and control circuitry shown in this
embodiment are made of traditional and inexpensive analog parts,
such as capacitors, NPN transistors, relays, and resistors, the
same functions could be carried out using available digital timing
and control elements. In this embodiment, control of the amount of
detergent dispensed is carried out by timing the actuation of the
air pump 66; however other possible embodiments could employ other
means for metering the liquid detergent.
[0046] FIG. 8 generally shows an alternative embodiment for use
with multiple washing machines, e.g., in a commercial laundry or a
coin laundromat. Here, an automated detergent dispensing system 222
has a large tank or reservoir 224 feeding a number of positive
displacement chamber arrangements 226a, 226b, 226c, etc., each
being connected via a respective detergent dispense hose 232 to an
associated washing machine 10 of a bank of washing machines. A
master console 236 on the system 222 provides for adjustment and
control over timing and volume. Here, a wall W is shown dividing
the laundry space between a laundry room where the washing machines
10 are located and a mechanical room where the multiple-washing
machine dispensing system 222 is positioned. In this embodiment, a
coin-operated station 110 (or other cash or card vend station) is
positioned atop the washing machine 10. This enables the user or
customer can purchase an amount of liquid detergent by inserting
coins (or other form of payment). This enables the system 222 to
dispense detergent at the appropriate time into the associated one
of the washing machines 10. A source of pressurized air, which may
comprise one or more of the air pumps 66 described earlier, may be
employed with associated control means for selectively pressurizing
one or another of the chamber arrangements 226a, ww6b, 226c, etc.,
and displacing the detergent from the positive displacement
pressure chambers to supply the washing machines with the
appropriate amount of detergent. Other sources of air pressure may
be employed, with associated valving.
[0047] FIG. 10 shows a variation of the embodiment of FIGS. 1 and
2, or the type in which the reservoir or tank 24 and pumping module
28 are mounted on the back of the washing machine 10 and the
control module 36 is mounted on the console 18, as discussed
previously in connection with FIGS. 1 and 2. However, this
embodiment provides for an alternative means of placement of the
detergent dispensing hose 32. Not all washing machines have a
suitable hole, such as hole 34, in the back panel for insertion of
the dispensing hose 32. In those that do not, it may be possible to
bore a 7/8-inch hole in the back panel above the drum or tub, and
then insert a rubber grommet to support the hose 32. However, the
owner or serviceman may not want to do that for one reason or
another. Thus an alternative routing of the detergent dispensing
hose can be achieved as shown here. The hose 32 is routed from
where it emerges from the reservoir 24 to one side or the other of
the washing machine 10. The hose is shown here as passing around
the right side. A flat, flexible hose portion 132 traverses an
upper edge of the cabinet and then goes below the lid or cover 20.
This flat portion 132 is only a small fraction of the thickness of
the tubular hose 32, so it does not interfere with the closing of
the lid. However, during a dispense cycle, the flat portion 132
will expand sufficiently to allow the detergent to flow. There is
normally enough clearance between the lid 20 and the top opening of
the cabinet 12 to allow the detergent to flow. However, it may be
convenient for the user to press the start button 38 to commence
the start cycle before closing the lid.
[0048] The flat, flexible hose portion 132 can be covered with a
U-channel 133 of appliance white plastic to conceal the hose for a
more aesthetic appearance. The U-channel 133 can be attached by a
suitable cement or by a Velcro.TM. fastener.
[0049] An alternate routing to the left side of the hose 32, with
an associated U-channel 133, is indicated in ghost lines.
[0050] While the foregoing embodiments have shown the system used
with top-loading washing machines, it would not be difficult to
adapt the system of this invention for automatic dispensing of
detergent into front-loading washers. In that type of machine,
there is typically a detergent receptacle, and the detergent
dispensing hose 32 could be placed there. Alternatively, the hose
32 can be routed to an upper portion of the wash chamber of the
machine.
[0051] Similar arrangements can be adapted for automatically
dispensing other laundry products, such as fabric softener or
bleach.
[0052] While the invention has been described and illustrated in
respect to a few selected preferred embodiments, it should be
appreciated that the invention is not limited only to those precise
embodiments. Rather, many modifications and variations would
present themselves to those of skill in the art without departing
from the scope and spirit of this invention, as defined in the
appended claims.
* * * * *