U.S. patent number 3,650,673 [Application Number 04/879,315] was granted by the patent office on 1972-03-21 for dry wash fabric cleaning method and apparatus.
This patent grant is currently assigned to General Electric Company. Invention is credited to William J. Ehner.
United States Patent |
3,650,673 |
Ehner |
March 21, 1972 |
DRY WASH FABRIC CLEANING METHOD AND APPARATUS
Abstract
A method for cleaning soil from fabrics, whereby the fabrics to
be cleaned are tumbled together with a quantity of water, detergent
and transfer agent. The transfer agent comprises a material having
a large surface area per unit mass, and the water comprises a
quantity sufficient only to dampen the fabrics. The tumbling causes
the water, the detergent and the transfer agent to contact the
fabrics, and causes soil from the fabrics to be distributed over
the combined exposed surface areas of the fabrics and the transfer
agent. Subsequently, the soiled transfer agent is separated from
the fabrics, whereby the fabrics are cleaned of the soil
distributed onto the transfer agent. An improved domestic automatic
clothes dryer is provided for performing therein the aforementioned
method.
Inventors: |
Ehner; William J. (Louisville,
KY) |
Assignee: |
General Electric Company
(N/A)
|
Family
ID: |
25373891 |
Appl.
No.: |
04/879,315 |
Filed: |
November 24, 1969 |
Current U.S.
Class: |
8/137; 8/158 |
Current CPC
Class: |
D06F
35/00 (20130101) |
Current International
Class: |
D06F
35/00 (20060101); D06l 001/02 () |
Field of
Search: |
;8/137,142,158
;69/23,28 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Scheel; Walter A.
Assistant Examiner: Coe; Philip R.
Claims
What I claim as new and desire to secure by Letters Patent of the
United States is:
1. A method of cleaning soil from fabrics, comprising the steps
of:
placing the fabrics to be cleaned into a rotatable enclosure along
with a quantity of transfer agent, detergent and water, wherein the
transfer agent comprises a foamed plastic material having a large
surface area per unit mass and the water comprises from 50 to 150
percent of the dry weight of the fabrics and is sufficient only to
dampen the fabrics;
rotating the enclosure so as to impart a tumbling action to the
fabrics thereby causing the water, detergent and the transfer agent
to contact the fabrics, and causing soil from the fabrics to be
distributed over the combined surface areas of the fabrics and the
transfer agent; and thereafter
separating the soiled transfer agent from the fabrics, whereby the
fabrics are cleaned of the soil distributed onto the transfer
agent.
2. The method of claim 1 additionally including the subsequent step
of circulating warm dry air through the enclosure while tumbling
the fabrics therein, whereby the fabrics may be brought to a
desired condition of dryness.
3. A method of cleaning soil from fabrics, comprising the steps
of:
placing the fabrics to be cleaned into a rotatable enclosure;
inserting into the enclosure a mixture of water, detergent and
transfer agent, wherein the transfer agent comprises a polyethylene
foam material having a large surface area per unit mass, and the
water comprises from 50 to 150 percent of the weight of the dry
fabrics and is sufficient only to dampen the fabrics;
rotating the enclosure so as to impart a tumbling action to the
fabrics thereby causing the water, detergent and the transfer agent
to contact the fabrics, and causing soil from the fabrics to be
distributed over the combined surface areas of the fabrics and the
transfer agent; and thereafter
separating the soiled transfer agent from the fabrics whereby the
fabrics are cleaned of the soil distributed onto the transfer
agent.
4. The method of claim 3 additionally including the subsequent step
of circulating warm dry air through the enclosure while tumbling
the fabrics therein, whereby the fabrics may be brought to a
desired condition of dryness.
5. A method of cleaning fabrics in a domestic automatic cloths
dryer of the type arranged for drying fabrics by tumbling them in
an enclosure rotatable about a non-vertical axis, and having
selectively energizable means adapted to heat and circulate a
stream of moving air through the enclosure to carry moisture away
from the fabrics, the method comprising the steps of:
placing the fabrics to be cleaned into the rotatable enclosure
along with a quantity of water, detergent and transfer agent,
wherein the transfer agent comprises a foamed polyethylene material
having a large surface area per unit mass, and the water comprises
from 50 to 150 percent of the dry weight of the fabrics and is
sufficient only to dampen the fabrics;
rotating the enclosure with the air heating and circulating means
substantially deactivated whereby the fabrics, water, detergent and
transfer agent are tumbled together;
the tumbling causing the water, the detergent and the transfer
agent to contact the fabrics, and causing soil from the fabrics to
be distributed over the combined surface areas of the fabrics and
the transfer agent; and thereafter
separating the soiled transfer agent from the fabrics, whereby the
fabrics are cleaned of the soil distributed onto the transfer
agent.
6. The method of claim 5 additionally including the subsequent step
of tumbling the fabrics in the rotatable enclosure with the air
heating and circulating means energized whereby the fabrics may be
brought to a desired condition of dryness.
Description
BACKGROUND OF THE INVENTION
This invention relates generally to a fabric cleaning process and,
more particularly, to a fabric cleaning process adapted to clean,
with a limited amount of water, many of fabrics of the type which
are commonly laundered in domestic automatic washing machines.
The prevailing method of washing fabrics automatically today
provides for the submersion of the fabrics in a large volume of
water containing soap or other detergents, agitation of the fabrics
therein to loosen and remove soil, extraction of the soiled liquid
from the fabrics, and one or more submergence rinsings of the
fabrics in a large volume of clean water. However, despite the
overwhelming acceptance of this method of submergence washing, the
process has a number of significant drawbacks. In the first place,
in order to perform the operation automatically, a relatively
costly machine is required. Although the reliability and operating
life of automatic clothes washers has been greatly increased in
recent years through significant inventive engineering advances,
there are nonetheless a variety of complex water supply,
circulation and drainage systems as well as reversible motor,
transmission and drive train parts, vibration isolation components,
and control mechanisms which are subject to failure, yet which are
essential to the automatic performance of the accepted washing
process.
A further drawback of the submergence fabric washing process is its
requirement of large quantities of water, usually heated. The
average washing cycle today employs over 40 gallons of water heated
to approximately 120.degree. F. Consequently, in the household of a
large family where the automatic washer completes one or more
cycles every day, the required expenditure for water, water
heating, and sewer connection can be quite significant.
In view of these problems and drawbacks inherently encountered with
the method of submergence washing, it is an object of the present
invention to provide a new and improved method of cleaning fabrics
which requires only a limited amount of water which may be
unheated.
It is a further object to provide such a process which may be
performed in an appropriately modified automatic dryer, thereby
obviating the complex washing systems of an automatic washer.
It is another object of my invention to provide a new and improved
process for cleaning fabrics which is effective to reduce or remove
certain stains which may be resistant to cleaning by the normal
submergence washing process conducted in a domestic washing
machine.
SUMMARY OF THE INVENTION
Briefly stated, in accordance with one aspect of the present
invention, there is provided a method of cleaning soil from fabrics
whereby the fabrics are tumbled together with a quantity of water,
detergent and transfer agent. The transfer agent preferably
comprises a material having a large surface area per unit mass, and
the water comprises a quantity sufficient only to dampen the
fabrics. The tumbling causes the water, the detergent and the
transfer agent to contact the fabrics, and causes soil from the
fabrics to be distributed over the combined surface areas of the
fabrics and the transfer agent. Subsequently, the soiled transfer
agent is separated from the fabrics, whereby the fabrics are
cleaned of the soil distributed onto the transfer agent.
In accordance with another aspect of the present invention, there
is provided an improved apparatus for carrying out the aforesaid
method, this apparatus comprising a domestic automatic clothes
dryer of the type arranged for drying clothes by tumbling them in
an enclosure rotatable about a non-vertical axis. By my invention
the clothes dryer includes selectively energizable means adapted to
heat and circulate a stream of moving air through the enclosure to
carry moisture away from the fabrics. In carrying out the cleaning
method in this apparatus, the fabrics to be cleaned are placed into
the rotatable enclosure along with a quantity of water, detergent
and transfer agent. The transfer agent preferably comprises a
material having a large surface area per unit mass, and the water
comprises a quantity sufficient only to dampen the fabrics. The
enclosure is then rotated with the air heating and circulating
means substantially deactivated, whereby the fabrics, water,
detergent and transfer agent are tumbled together with no
substantial drying of the fabrics. The tumbling causes soil from
the fabrics to be distributed over the combined surface areas of
the fabrics and transfer agent. Subsequently, the soiled transfer
agent is separated from the fabrics, whereby the fabrics are
cleaned of the soil distributed onto the transfer agent.
BRIEF DESCRIPTION OF THE DRAWINGS
While the specification concludes with claims particularly pointing
out and distinctly claiming the subject matter which is regarded as
the invention, it is believed the invention will be better
understood from the following description of the preferred
embodiments taken in conjunction with the accompanying drawings, in
which:
FIG. 1 is a side elevational view of the clothes dryer adapted to
clean fabrics according to the method of my invention;
FIG. 2 is a schematic electric circuit diagram illustrating a
control circuit for the dryer of FIG. 1; and
FIG. 3 is a sequence control chart illustrating the positions of
the switches in the circuit of FIG. 2 during the sequence of
operation of the machine of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In accordance with one primary aspect of my invention, a new and
improved method is provided for cleaning soil from fabrics. By the
term "soil" I refer both to oleophobic oil-like materials such as
body oils, cooking oils, and greases as well as particulate
substances such as clay, sand, dust, grit, pumices, and the like
which are substantially non-organic in nature.
The cleaning of fabrics in accordance with my new and improved
method, hereinafter called the "dry wash" method, employs only a
limited quantity of water sufficient to dampen the fabrics.
Although heated water may be employed, the process may be performed
with unheated water. By the term "dampen" I mean wetting the
fabrics to a condition where there is some free water present on
their surfaces during the cleaning process. The free water should
be present in an amount sufficient to give mobility to the
detergent employed in the cleaning process so that it is
distributed across all of the fabric and transfer agent surfaces.
In this regard, a quantity of water equal to 50 to 150 percent of
the dry weight of the fabrics has been found to be sufficient,
depending upon the type of fabric being cleaned. In terms of more
visual quantities, approximately three pints of water may be used
per 3 pound load of cotton fabrics to be cleaned.
To augment the wetting action of the water and to assist in
loosening and lifting soil from the fabrics, a quantity of
detergent is employed in the dry wash process. The detergent used
may comprise a commercially available or a specially formulated
liquid or powdered detergent which may have additives such as, for
example, germicides, optical brighteners, deodorants, etc. One such
commercially available liquid detergent which has performed
successfully in the dry wash process is Cinch, manufactured by
Proctor & Gamble. In quantity 75 grams of Cinch used with three
pints of water per three pound fabric load has been found to
perform adequately.
It will be noted that 75 grams of detergent such as Cinch used with
3 pints of water provides a substantially higher detergent
concentration than is used in conventional submergence washing
operations. In other words, an important aspect of my invention is
that the fabrics are subjected to a detergent concentration which
is many times that of the normal submergence washing operation
wherein, in one typical example, approximately the same amount of
detergent, i.e., 75 grams, will be used with 15 gallons of water.
In addition to providing good soil removal, the high detergent
concentration has the further advantage that certain stains which
may be resistant to normal submergence washing are reduced or
removed by my cleaning method.
In order to clean fabrics, the dry wash process relies on the use
of a transfer agent. The transfer agent, which ideally comprises a
material having a large surface area, is brought into repeated
contact with the fabrics to effect the release of soil therefrom
and the distribution of such soil onto the combined surface areas
of the transfer agent and the fabrics. The transfer agent acts both
as a scrubbing medium to aid in releasing soil from the fabrics and
as a receiving medium for retaining a significant portion of the
soil so released.
The repeated contact of the transfer agent and fabrics may be
readily accomplished by tumbling together the fabrics, the water,
and the detergent in contact with the transfer agent in an
enclosure rotatable about a non-vertical axis, such as the drum of
a horizontal axis domestic automatic clothes dryer. In accordance
with another aspect of my invention, an automatic dryer having
appropriate improvements enabling it to carry out the dry wash
method will be described later in this specification.
In my presently preferred method, the transfer agent comprises a
medium which is tumbled together with the fabrics thereby to cause
the repeated contact therebetween. A number of materials may be
utilized as transfer agents, it being important, however, that the
material employed have a relatively high surface area per unit mass
and that it have a compatible affinity for the soil to be cleaned
from the fabrics such that the soil can be picked up by the
transfer agent. As will be apparent, the operation of the transfer
agent may be augmented by appropriate treatment to increase its
affinity for soil. Furthermore, the transfer agent may be either
re-usable or throwaway as convenience may dictate. Obviously, if
the transfer agent is sufficiently inexpensive to be disposed of
after a single use, the problem of purging the transfer agent for
reuse is obviated.
It will be understood that the transfer agent used may be selected
so as to lend itself to automatic separation, whereby the complete
dry wash process may then be performed automatically and may also
be performed automatically in sequence with other fabric laundering
cycles such as the "dry rinse" method disclosed in an application
Ser. No. 879,031 filed concurrently herewith by L. Loeb and
assigned to the assignee of the instant invention.
Materials which have been successfully tested as transfer agents
are terrycloth swatches, foamed rubber and foamed plastic blocks
and particles of various configurations, sponges and the like. A
transfer agent which appears to be advantageous for use in
connection with the dry wash and dry rinse processes is
polyethylene foam, as taught in two applications Ser. No. 879,033
(Docket No. 9D-HL-9411 - DePas) by L. A. DePas and Ser. No. 879,034
(Docket No. 9D-HL-9473 - Henderson) by B. D. Henderson (U.S. Pat.
No. 3,593,544), both applications being filed concurrently herewith
and assigned to the assignee of the instant invention. As pointed
out in the DePas and Henderson applications, polyethylene foam has
the advantage of being heat shrinkable, whereby, the soiled
transfer agent, once separated from the fabrics, may be
significantly reduced in volume by heat shrinking to facilitate its
disposal.
In connection with a 3 pound load of fabrics, one-eighth pound of
polyethylene cubes measuring one-fourth inch on each side have been
used successfully. By volume, this quantity of transfer agent may
be better visualized as approximately 2 quarts of small, resilient
foamed cubes.
Another manner of bringing the fabrics into contact with the
transfer agent is to affix the transfer agent to the inner surface
of the fabric enclosure. For example, appropriate portions of the
inner drum surface may be covered with a removable sheetlike
transfer agent. Then as the drum is rotated, the fabrics are
brought into repeated contact with the transfer agent during their
random tumbling in the drum.
In the performance of the dry wash method, the fabrics may be
inserted into the drum of a horizontal axis domestic automatic
dryer, having certain improvements to be explained later, along
with the water, detergent and transfer agent. The dryer drum or
enclosure is then rotated whereby a tumbling action is imparted to
the fabrics thereby causing the water, detergent and transfer agent
to contact the fabrics, and causing soil from the fabrics to be
distributed over the combined exposed surface areas of the fabrics
and the transfer agent. The larger the surface area of the transfer
agent, the greater the amount of soil which will be removed from
the fabrics and distributed onto the transfer agent. By such
distribution of the soil, areas of soil concentration on the
fabrics are substantially eliminated. Also due to the high
detergent concentration and the repeated contact between the
fabrics and the transfer agent, many stains on the fabrics, if not
all such stains, will be reduced or removed.
It will be realized that my new and improved method of cleaning
fabrics does not utilize the water and detergent solution as a
carrier to pick up and hold the soil from the fabrics, and
subsequently carry it to drain. Rather, the dry wash method
utilizes the water and detergent to dampen the fabrics and loosen
the soil, thereby permitting a thorough distribution of the soil to
be effected over the combined surface areas of the fabrics and the
transfer agent by repeated contact of the fabrics with the transfer
agent and with other fabric portions. By this method, although a
quantity of the soil will be left on the fabrics, it will be
substantially reduced from the original quantity and will be
distributed so as to leave no objectionable areas of soil
concentration.
Subsequent to such tumbling, the soiled transfer agent is then
separated from the fabrics, whereby the fabrics are cleaned of the
soil distributed onto the transfer agent. Such separation may be
accomplished by mechanical means designed to accommodate the
particular transfer agent used, or by manually removing the fabrics
from the transfer agent. One such automatic approach will be
discussed later in connection with a particular domestic automatic
drying apparatus.
In accordance with another aspect of my invention, the fabrics may
be subsequently dried by tumbling the fabrics in the enclosure
while circulating warm dry air therethrough. Such a subsequent
drying step readily lends itself to performance in a domestic
automatic clothes drying machine, a number of modifications and
improvements to the machine are essential. To better enable one
skilled in the art to understand the method of my invention,
reference is made to the drawings, and initially to FIG. 1 where
there is illustrated a domestic automatic clothes dryer 10
including an appearance and protective outer cabinet 11 having a
door or closure 12 to provide access to the interior of the cabinet
for loading and unloading fabrics. Provided on the top 13 of
cabinet 11 is a control panel 14 which may, in a conventional way,
include a suitable manual control 15 connected to a control
assembly 16 mounted in the panel 14. By manual setting of control
15, the machine may be caused to start and automatically proceed
through a cycle of operation.
Within cabinet 11, there is provided a clothes tumbling enclosure
or drum 17 mounted for rotation on a substantially horizontal axis.
Drum 17 is substantially cylindrical in shape, having a center
cylindrical wall portion 18, and outer cylindrical wall portions 19
and 20, located respectively adjacent an annular front wall 21 and
a circular rear wall 22 of the drum. Wall portions 18, 19, 20 are
substantially imperforate to enable the drum or enclosure 17 to
hold a depth of approximately 1 inch of liquid. On the interior
surface of wall portion 18 there are a plurality of clothes
tumbling ribs 23 so that clothes are lifted up when the drum
rotates, and then permitted to tumble back down to the bottom of
the drum. The front of the drum 17 may be rotatably supported
within outer casing 11 by by suitable idler wheels, one of which is
indicated by the numeral 24. These wheels are rotatably secured to
the top of a member 25 which extends up from the base 26 of the
machine. The wheels 24 are disposed beneath the drum, in contact
with portion 19, so as to support the portion 19 on each side to
provide a stable support.
The rear end of drum 17 receives its support by means of a stud
shaft 27 extending from the center of wall 22. Shaft 27 is secured
within a bearing 28 formed in a baffle structure 29 which, in turn,
is rigidly secured to the back wall 30 of the cabinet 11 by any
suitable means such as welding at a number of points 31. With the
arrangement shown the drum may rotate on a horizontal axis, with
rollers 24 providing the front support and stub shaft 27 within
bearing 28 providing the rear support.
In order to provide for the flow of a stream of drying air through
the clothes drum, it is provided with a central aperture or opening
32 in the front wall 21 and a plurality of perforations 33 in the
rear wall 22. The perforations 33 in the present case are formed to
extend around the rear wall in an annulus. The opening 32 is in
alignment with the opening in cabinet 11 covered by door 12, and
thus serves a dual purpose in that it also provides access to drum
17 for loading and unloading fabrics.
As has been stated, baffle structure 29 is rigidly secured to the
back wall 30 of cabinet 11. Baffle structure 29 also serves to
support heating means 34 which includes two resistance type
electrical heating elements 35 and 36, appropriately insulated from
the baffle member. Elements 35 and 36 may be annular in shape so as
to be generally coextensive with perforations 33 in drum 17. A
baffle member 37 is rigidly secured to the rear wall 22 of the drum
17 outside the ring of perforations 33 and within the stationary
baffle structure 29, so that an annular air inlet 38 is defined by
baffles 29 and 37. In this manner a passage is formed for air to
enter air inlet 38 between the baffles, pass over the heating means
34, and then pass through centally located openings 39 formed in
baffle 37 and perforations 33 into the interior of drum 17.
The front opening 32 of the drum is substantially closed by means
of a stationary bulkhead generally indicated by numeral 40.
Bulkhead 40 is made up of a number of adjacent members including
the inner surface 41 of the access door 12, a stationary frame 42
formed as a flange on front wall 43 of the cabinet, the inner
surface of an exhaust duct formed by the cooperation of member 44
and the front wall 43 of the cabinet, and an annular flange 45
mounted on the frame 42 of the front wall 43. It will be noted that
a suitable clearance is provided between the inner edge of aperture
32 and the edge of bulkhead 40 so that there is no rubbing between
the drum and the bulkhead during rotation of the drum. In order to
prevent substantial air leakage through the aperture 32, a suitable
ring seal 46 is secured to the flange 45 in sealing relationship
with the exterior surface of the drum wall 21. Door 12, whose inner
surface forms part of the bulkhead closing the opening, is mounted
on cabinet 11 so that when the door is opened fabrics may be
inserted into and removed from the drum through the door frame 42.
It will be noted that the door includes an outer, flat imperforate
section 47 and an inwardly extending hollow section 48, mounted on
the flat outer section. Hollow section 48 extends into the door
frame 42 when the door is closed, and the door surface 41 which
comprises part of the combination bulkhead 40 is actually the inner
wall of the hollow section.
The air outlet from the drum is provided by a perforated opening 49
formed in the inner wall 41 of hollow door section 48. The bottom
wall section of door 12 and the adjacent wall of door frame 42 are
provided with aligned openings 50 and 51, opening 51 providing an
entrance to a duct 52 formed by the cooperation of member 44 with
front wall 43. A lint trap 53 may be positioned in the exhaust duct
52 within opening 51 and supported by the door frame 42. Duct 52
leads downwardly and communicates with a housing 54. Housing 54
contains a blower 55 driven by motor 56 through clutch 57. The
blower draws heated air through the duct 53 and then exhausts it
from the cabinet 11 through an appropriate duct (not shown).
In addition to driving the blower, motor 56 constitutes the means
for effecting rotation of drum 17. In order to effect this
rotation, motor 56 is provided with a shaft 58 having a small
pulley 59 formed at one end thereof. A belt 60 extends around the
pulley 59 and also entirely around the wall section 18 of drum 17.
The relative circumferences of the pulley 59 and the wall section
18 cause the drum to be driven by the motor at a speed suitable to
effect tumbling of fabrics in the drum. In order to effect proper
tensioning of the belt 60, a suitable idler assembly 61 is secured
to the same support 62 which supports one end of the motor. Thus,
air is pulled through the drum and, at the same time, the fabrics
within the drum are tumbled. When the air is being heated by
heating elements 35 and 36, the heated air passing through the drum
causes vaporization of the moisture from the clothes, the vapor is
carried off with the air as it passes out of the machine.
Referring now to FIG. 2, there is shown a schematic electric
circuit diagram illustrating a basic or simplified control
arrangement for the dryer of FIG. 1. It will be understood that
many refinements such as temperature selection means, multiple
cycle selection means, and fabric temperature or resistance
responsive control means for automatically concluding the operation
of the dryer, etc., have not been shown in the circuit of FIG. 2
for the sake of simplicity. As shown, the entire control system of
the machine may be energized across a three-wire power supply
system which includes supply conductors 63 and 64 and a neutral
conductor 65. For domestic use, conductors 63 and 64 will normally
be connected across a 230 volt power supply, with 115 volts
appearing between the neutral line 65 and each of the conductors,
and with the neutral line being at ground voltage. Motor 56,
connected between conductors 63 and 65, is a single phase induction
motor having a main winding 66 and a start winding 67, both
connected at a common end to a conductor 68. Through a conventional
door switch 69 (which is closed when door 12 is closed and open
when the door is open) conductor 68 is connected to conductor
65.
Start winding 67 is connected in parallel with main winding 66
under the control of a speed responsive device such as that shown
at 70, which is schematically shown as connected to rotor 71 of the
motor. The speed responsive device 70 controls a switch 62 which is
engageable with either a contact 73 or a contact 74. Switch 72 is
engaged with contact 73 when the machine is at rest, and moves into
engagement with contact 74 as the motor comes up to speed. It can
readily be seen that engagement with contact 73 connects the start
winding 67 in parallel with main winding 66, which movement of
switch 72 away from this position opens the start winding. Thus, as
rotor 71 comes up to speed, the start winding becomes deenergized
and the motor then continues to run on the main winding 66
alone.
The starting of the motor is provided by a manually operable switch
75 which may, for instance, in the structure of FIG. 1, be moved to
its closed position by depressing manual control 15. Switch 75
connects the motor to supply conductor 63 through contact 76 of a
switch 77. The switch 75 is normally biased to the open position as
shown in FIG. 2. When control 15 is depressed, assuming contacts 76
and 77 are closed, energization of the motor 56 is provided and,
within less than a second under normal circumstances, the motor
comes up to speed so that switch 72 moves from contact 73 to
contact 74. As a result of this movement of centrifugally operated
switch 72, the main winding 66 of motor 56 continues to be
energized by a bypass around switch 75 when control 15 is released,
thus opening switch 75.
The switch 77 is controlled by a cam 78 which, in turn, is
controlled by a time motor 79 of the shut-off or timing control
means. The cam 78 and timer motor 79 also are connected to manual
control 15 so that rotation of the manual control causes the cam to
rotate and close switch 77. Thereafter, the cam 78 is controlled by
the timer motor 79 and, after a predetermined period of operation
of the timer motor, the cam is effective to cause switch 77 to be
opened for terminating or interrupting the operation of the
machine.
An energizing circuit is also completed for heating means 34
through the following circuit. Starting at conductor 63, the
circuit proceeds through a switch 80 and a dryness sensing
thermostat 81 to the heater 34, and then through a conventional
safety thermostat 82, and through switches 83 and 84 to conductor
64. Switch 80 is controlled by a cam 85 which, in turn, is
controlled by timer motor 79. Switch 83 is controlled by a solenoid
86 and is normally closed when solenoid 86 is not energized. Switch
84 is centrifugally responsive to the speed of rotor 71 and is
closed only when motor 56 has come up to speed so that there can be
no energization of the heating means 34 except when motor 56 if
operating properly. Thermostat 81 is positioned so as to sense the
temperature of the fabrics within drum 17, or a temperature which
varies substantially directly with the clothes temperature. When
the clothes are at a temperature which indicates dryness,
thermostat 81 will open, deenergizing heater 34.
With the possible exception that the wall portions 18, 19 and 20 of
drum 17 are imperforate, the foregoing description substantially
sets forth the configuration and arrangement of known domestic
automatic dryers.
In order to carry out the dry wash method of my invention in the
machine of FIG. 1, it is necessary that the means adapted to heat
and circulate air moving through the enclosure be selectively
energizable. It is to be understood that during the dry wash
cleaning cycle, it is desirable to deactivate or substantially
disable both the air heating and air circulating means, so as to
avoid undesirable evaporation of the limited amount of water used
to wet the fabrics.
Therefore, according to one aspect of the present invention,
control means are provided which are adapted to disable the air
circulating means or blower 55 and the heating means 34 so as to
selectively permit the rotation of the drum or enclosure 17 with or
without the flow of heated air therethrough. Such control means, in
the embodiment of FIGS. 1 and 2, comprises solenoid 86 connected on
one side to neutral conductor 65, and on the other side through a
switch 87 to conductor 63. The switch 87 is controlled by a cam 88
which, in turn, is controlled by timer motor 79. Solenoid 86
operates an armature 89 which, when solenoid 86 is energized,
disconnects motor 56 from blower 55 by means of clutch 57, and
which simultaneously opens switch 83. Thus, when solenoid 86 is
energized, blower 55 and heating means 34 are deenergized.
As may best be seen in FIG. 1, clutch 57 comprises two frictionally
engageable members 90 and 91, member 90 being connected to output
shaft 58 of motor 56, and member 91 being connected to blower 55.
Members 90 and 91 are normally held in driving engagement by means
of compression spring 92. However, when armature 89 is moved
inwardly of solenoid 86 by energization of solenoid 86, lever 93
pivoted at 94 and attached to armature 89 by link 95 operates to
move member 90 out of engagement with member 91, thereby
disengaging blower 55 from motor 56.
It will be apparent that a number of other systems may be provided
to deenergize or substantially disable the air heating and
circulating means. A valve means, for instance, could be installed
in the air flow line at the inlet or outlet of the blower, or the
air flow could be diverted from circulating through the drum. A
variety of such modifications will be apparent to one skilled in
the art. Furthermore, if very cold water is introduced initially
into the dryer drum 17, it may be desirable to provide heat to the
dryer drum to bring the temperature thereof into the desirable
range for cleaning. To accomplish this, a separate heater may be
provided or heating means 34 may be used with suitable
controls.
In operation, the machine of FIG. 1 may be programmed to perform
the entire cleaning, transfer agent separation, and drying
functions, or separate ones of such functions. Cams 85 and 88 may
be so designed such that during the cleaning function, switch 87 is
closed causing solenoid 86 to deenergize blower 55 and heating
means 34, while during the drying operation, switch 87 is open and
switch 80 is closed. By this arrangement, as may be better seen in
FIG. 3, the blower 55 is deenergized during cleaning but operates
continuously during drying, while the heating means 34 is
deenergized during cleaning and selectively energized during drying
under the control of sensing means 81.
In order to perform the dry wash process of my invention in the
machine of FIG. 1, the fabrics to be cleaned are placed into drum
17 along with the aforedescribed quantity of water, detergent and
transfer agent. Control 15 is then moved to initiate operation of
the machine in the dry wash mode wherein heating means 34 and
blower 55 are deactivated during rotation of drum 17. The fabrics,
water, detergent and transfer agent are thereby tumbled together
causing soil and detergent from the fabrics to be distributed over
the combined surface areas of the fabrics and transfer agent, as
previously described. Following this tumbling operation, separation
of the transfer agent may be accomplished automatically during the
initial portion of the drying operation. By way of illustration, if
the transfer agent being used is 1/4-inch cubes of polyethylene
foam, such cubes are sufficiently buoyant to be carried out of drum
17 by the initiation of air circulation therethrough, whereafter
such cubes may be caught in lint trap 53 or the like. In the
alternative, such separation may be performed manually between the
cleaning and drying operations.
From the foregoing description it should now be apparent that my
new and improved dry wash method may be readily carried out in a
domestic automatic clothes dryer having the improvements presented
herein.
As will be evident from the foregoing description certain aspects
of the invention are not limited to the particular details of the
examples illustrated, and it is therefore contemplated that various
other modifications or applications will occur to those skilled in
the art. It is therefore intended that the appended claims shall
cover such modifications and applications as do not depart from the
true spirit and scope of the invention.
* * * * *