US3203209A

US3203209A - Dry cleaning apparatus

Info

Publication number: US3203209A
Authority: US
Inventors: David R Paulick
Original assignee: Motors Liquidation Co
Current assignee: Motors Liquidation Co
Priority date: 1963-07-31
Filing date: 1963-07-31
Publication date: 1965-08-31
Anticipated expiration: 1982-08-31

Description

2 Sheets-Sheet 1 Filed July 31, 1965 0 O O 0 O O O O 0 INVENTOR. Dal/[d Pa /z United States Patent 3,203,209 DRY CLEANING APPARATUS David R. Paulick, Dayton, Ohio, assignor to General Motors Corporation, Detroit, Mich., a corporation of Delaware Filed July 31, 1963, Scr. No. 299,049 7 Claims. (Cl. 682tl7) This invention relates to a dry cleaning apparatus and more particularly to a controlled water injection system for a dry cleaner having an electronic relative humidity sensing arrangement.

The proper operation of an effective dry cleaning system requires that all soil, both water soluble and solvent soluble, be removed from the garments being cleaned. For this reason perchlorethylene and detergent are frequently combined in a water-solvent solution to perform the cleaning task, and it is essential that the water content or relative humidity of the solution be maintained at a predetermined level in order to optimize the efiectiveness of the detergent in removing water soluble spots.

Accordingly, it is an object of this invention to provide an improved system for sensing the relative humidity of a dry cleaning solution and, in response thereto, providing a controlled supply of water to the solution in order to maintain the solution at a desired relative humidity.

Another object of this invention is the provision for supplying make-up water to the dry cleaning solution only during a clothes agitation cycle, thereby to assure homogeneous mixing of solvent and water.

It is a further object of this invention to provide in a dry cleaner an electronic sensing system in combination with a venturi for sensing the relative humidity of a dry cleaning solution and then supplying make-up Water thereto.

A more specific object of this invention is the provision of a dry cleaner having a substantially enclosed solvent reservoir in combination with a circulating air system for drying clothes after cleaning, said circulating air system serving to draw vapor from the solvent reservoir into relative humidity sensing relationship with the electronic sensing system.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings wherein a preferred embodiment of the present invention is clearly shown. a

In the drawings:

FIGURE 1 is a front sectional view, partly in elevation, of a dry cleaning apparatus suitable for use with this invention; and

FIGURE 2 is an enlarged fragmentary schematic representation of the electronic system for sensing and controlling the relative humidity of a dry cleaning solvent solution.

Suitable for use with this invention and turning now to FIGURE 1, a unitary dry cleaning systernor apparatus of the replaceable filter cartridge type is ilustrated. The system includes an outer cabinet 10 for partially enclosing a clothes cleaner or agitating apparatus 12 and'a clothes dryer or drying apparatus 14. Note that the clothes dryer 14 is elevated above the floor to provide for a filter compartment 16 therebelow. The clothes cleaner 12 has a top access door 18 which is pivotally openable for inserting and removing fabrics from the cleaner.

The clothes dryer 14 has a front access door 20 which faces the washer access door 18 adjacent one side thereof. This arrangement places the access doors 18 and 20 in a confined area defined by a top wall 22 and a side wall 24 of the dry cleaning cabinet 10a perforate grille 26 at the rear of the confined space operating to withdraw V 3,203,209 Patented Aug. 31, 1965 fumes from the area. The outlet or vent grille 26 is connected to the atmosphere through an exhaust blower at the rear of the cabinet.

The cleaner or agitating apparatus 12 is shown com prised of an outer cabinet 28 in the top wall of which is located the access door 18, hinged along a rear edge thereof. Within the washer cabinet 28, a generally cylindrical, imperforate solvent container 30 is disposed which includes an access opening in axial alignment with the top access lid 18 of the washer. The lower end of the solvent container 30 includes a drain opening 32 draining the solvent container from a lowermost portion thereof. A generally cylindrical spin tub or container 34 is rotatably supported in the solvent container and includes a plurality of circumferentially arranged outflow ports 35 around an upper portion thereof and a top access opening 36 which aligns with the door 18 immediately above. Within the spin tub 34, an agitator 37 is adapted for vertical reciprocation. A motor-driven agitating and spinning mechanism is shown generally at 38 and is adapted to vertically reciprocate the agitator 37 when operated in one manner and to rotate or spin the tub 34 when rotated in another manner.

The clothes dryer 14 is a conventional, single pass, circulating air dryer substantially like that taught in the patent to Whyte 2,843,945 issued July 22, 1958. The dryer includes a horizontally rotatable tumbling drum or container 38 having a perforate rear wall 40 and a front access opening 42 in alignment with the dryer door 20. A drying heater 44 is disposed adjacent the perforate rear wall 40 of the tumbling drum and is adapted to be energized for drying clothes within the tumbling drum. During operation of the heater 44 and rotation of the tumbling drum 38, air is circulated by a fan 46 connected with the drum access opening 42 by way of a front duct 48,, said front duct being exhausted to atmosphere by the fan through an exhaust duct 50.

The solvent circulating system for a dry cleaning fluid or solven-t,.such as perchlorethylene (a somewhat toxic dry cleaning fluid) or Valclene (a nontoxic dry cleaning fiuid made by Du Pont Corporation which is essentially Freon 113) will now be described with reference to FIGURE 1. The main components of the circulating system include a sump or solvent reservoir 52 having a top wall 54 with an air vent and spill-over return 56, thereby to substantially enclose the solvent and its vapor. Immersed in the solvent is a cooling coil 57 through which Water courses, said water being thermostatically controlled to maintain the solvent at its best cleaning temperature. Refrigerated Water may be used if the domestic supply thereof is too warm. Above the sump top wall 54 is a pump 58 which has its inlet connected through a solvent suction dip tube 60 to the bottom of the sump 52. A filter 62 is adapted to receive the output of the pump through a conduit 64 which connects to the inlet 66 of the filter. The case of the filter 62 is positioned angularly in the filter compartment 16, such that a gravity drain 68 extends through the sump wall 54 and includes a valve 70 manually openable to substantially drain the filter of solvent when the dry cleaning system is shut down. A solvent by-pass line 72 is provided at the top of the filter case to bleed air from the case. Unfiltered solvent passes through the by-pass line during operation of the filtration system and returns to the solvent reservoir. I

At one end of the filter, an outlet fitting 74 connects by way of a solvent supply conduit 76 through a two-way or two-position valve 78 and supply conduit 79 to the tub access opening 36a terminal portion 80 overlying the top of the spin tub 34. The two-position valve 78 may be controlled such as by a solenoid into a first position connecting the filter outlet 74 to the spin tub 34 and a 3 second position connecting the filter outlet to a sump return line 82. Completing the circulating system is a conduit 84 which connects to the drain outlet 32 of the solvent container 30. This conduit 84 enters the sump 52 by way of a button trap 86, access to which is gained through a removable lid thereabove for cleaning.

The fluid circulation system operates as follows. The pump 58 draws dry cleaning fluid or solvent from sump 52 through the dip tube 60. This dry cleaning fluid, cleaned of large objects by the trap 86, is forced through the conduit 64 to the filter 62 which is effective to remove small solids, solubles and any loose carbon particles from the dry cleaning fluid. After an initial period in which the two-position valve 78 returns the solvent to the sump, the valve is actuated to discharge the solvent from the filter by way of the conduit 76 and its end nozzle 80 into the spin tub 34. When the level of dry cleaning fluid within the tub reaches the outflow ports 35, the dry cleaning fluid will continue to overflow into the solvent container 30 and will return by gravity through the conduit 84 to the sump 52. For additional details on the replaceable cartridge type of dry cleaning system, reference may be had to the copending application Serial No. 120,420, filed June 28, 1961, now Patent No. 3,110,170, and to the other applications referred to therein and assigned to the same assignee.

In the afor-egoing equipment a cleaning solution of perchlorethylene and detergent will remove or dissolve most of the soil from the garments being cleaned, and water soluble spots not removable in dry cleaning solvent alone can often be removed by spotting with water prior to dry cleaning. Such prespotting requires a certain amount of skill and extra time on the part of the attendant. Thus, it appears that the presence of water in a dry cleaning solution is helpful in the removal of water soluble spots and it is known that even an increase in detergent concentration does not sufficiently increase the systems potential for spot removal unless accompanied by an increase in the relative humidity (R.H.) of the solvent, i.e., the water content of the cleaning solution. Moreover, carbon soil removal will also increase slightly with the solvent solution at a higher RH. and linting on the clothes will be reduced.

On the other hand, an excess of water in the dry cleaning solution has some disastrous side effects, such as severe wrinkling of the garments being cleaned, shrinkage, and higher redeposition of soil or graying of the garments.

The foregoing suggests that the proportion of water to solvent maintained in the dry cleaning system is critical and it is to improved apparatus for sensing and controlling this proportion that this invention is directed.

General The electronic sensing system of this invention is comprised generally of an electronic controller and magnetic amplifier 100, a relative humidity sensing element 102 and a sniffer box 104the sniifer box operating off of the negative pressure in the exhaust duct 48 of the clothes dryer 14 to draw vapor from the top of the sump across the element 102. The water injection system consists of a solenoid valve 106, a manually operated water control valve 108, a water fount or catch basin 110 exposed in the area of the vent grille 26 and a venturi 112.

Electronic sensing system 1 The controller 180 may be a Minneapolis-Honeywell R7088C versa-tran adjustable relative humidity controller or equivalent which consists of a bridge circuit in which the humidity sensing element 102 is one leg of the bridge. With a change in the humidity of the dry cleaning solution in the sump (the amount of moisture the vapor above the dry cleaning solution is holding compared to what it could hold), the resistance of the sensing element 102 changes, thereby unbalancing the bridge. This signal is amplified and used to activate a relay whose contact switch 114 closes to energize the solenoid valve 106 in a water supply line 116 which is tapped into the solvent cooling coil 57 as at 118.

The amplifier portion of the controller is energized through conductors 120 Whenever the two-way valve 78 in the tub fill line 79 is energized in its first position to condition the solvent supply conduit for continuous solvent supply during the clothes cleaning cycle. The solenoid water valve 106 is energizable only when the clothes agitation circuit is energized, i.e., when the agitating and spinning mechanism 38 is energized in a manner to vertically reciprocate the agitator 37. Thus, in order to add water to the dry cleaning solution, both the two-way valve 78 and the mechanism 38 (for agitate) have to be energized. Such an arangement permits the add tion of water to the continuously supplied dry cleaning solution only during the agitate cycle of the dry cleaning apparatus. If the clothes were not being agitated, a possibility would exist whereby droplets of free water would impinge upon certain of the garments, giving rise to problems such as shrinkage and uneven cleaning. By agitating the clothes concurrently with the supply of water to the solvent, a thorough mixing occurs and all garments are subjected to a homogeneous dry cleaning solution.

The humidity sensing element 102 is made of two gold electrodes having intermeshed legs embossed on one side of a plastic base. A humidity sensitive film of polyvinyl alcohol and lithium chloride is applied over the gold grid. A suitable element of this type is Minneapolis-Honeywells Q229-102O element.

The sensor element 102 is located inside the sniiter box 8 104 which is attached to the underside of the dryer exhaust duct 48 or any other negative pressure area of the dryer air circulating system such as the filter drying compartment taught more fully in copending application Serial No. 282,838, filed May 22, 1963, and assigned to the same assignee. The negative pressure occurring inside the duct 48 draws perchlorethylene vapors through the duct 126 from the solvent sump 52 and, more particularly, from the vapor space above the level 128 of the solvent. The suction of the fan 46 draws these vapors over the element 102 and into the exhaust duct 51). It is the relative humidity of the vapors passing over the element 102 that are sensed by the controller 100 and subsequently used to control all the admission of water to the circulating dry cleaning solution.

Water injection system The water to be injected into the system is taken from the solvent cooling coil 57 as at 118 and the injection or entrainment is controlled by the solenoid valve 186 and the manual valve 108. An air gap exists between the water supply 116 and the catch basin so that the droplets of water supplied are visible to the user of the dry cleaner. The venturi 112 in the tub fill line 79 creates a negative pressure which is used to draw the water from the catch basin 110 into the tub fill line through an inlet tap 130 in the venturi. In operation, approximately one and onehalf to two and one half ounces of water are added to the solvent each time a reduced relative humidity is sensed by the element 102.

It should now be seen that an improved system has been provided for sensing relative humidity of dry cleaning solvent. The negative pressure available in the circulating air system of a dryer is used to draw vapor from the solvent sump over a sensing element of an electronic relative humidity sensing system, thereby to signal a proper injection or entrainment of makeup water into the dry cleaning solvent. Then the entrainment of this water is eflected through the negative pressure available at a venturi in the tub fill line.

While the embodiment of the present invention as herein disclosed constitutes a preferred form, it is to be understood that other forms might be adopted.

What is claimed is as follows:

1. In combination,

(a) means forming a first container adapted to contain a dry cleaning solvent such as perchlorethylene or the like for dry cleaning clothes,

(b) means forming a second container adapted to contain the clothes after dry cleaning thereof,

(c) means including said second container for conveying a stream of air through said second container for drying the clothes therein,

(d) means forming a substantially closed sump means containing a predetermined level of dry cleaning solvent therein,

(e) means including a water cooling line in said sump means below said predetermined level for cooling said dry cleaning solvent,

(f) means including a solvent supply conduit connected in supply relationship to said first container for effecting the recirculation of dry cleaning solvent between said sump means and said first container,

(g) mean-s for entraining water into the dry cleaning solvent being supplied to said first container including a venturi in said solvent supply conduit having a suction inlet and a catch basin attached thereto, a water supply conduit having one end connected to said water cooling line and its other end connected in air gap, gravity flow relationship to said catch basin, and valve means in said water supply conduit openable for passing a regulated amount of water to said catch basin for subsequent entrainment through said venturi into the slovent being supplied to said first container,

(h) and control means for controlling said valve means, said control means including sensing duct means interconnecting the air stream conveying means and said sump means in a manner to draw therethrough a stream of vapor from above said predetermined level of dry cleaning solvent in said sump means for sampling the relative humidity of the dry cleaning solvent in said sump means, means in relative humidity sensing relationship to said stream of vapor for effecting a control signal in response to the relative humidity sensed, and means for processing said control signal in a manner to open said valve means when the relative humidity of said streams of vapor is below a predetermined value.

2. The combination of claim 1 wherein said catch basin is in an exposed position above said first container.

3. In combination,

(f) means including a solvent supply conduit connected in supply relationship to said first container for elfecting the recirculation of dry cleaning solvent between said sump means and said first container,

(g) means for supplying water to the dry cleaning solvent including a water supply conduit and valve means in said water supply conduit openable for passing a regulated amount of water to the dry cleaning solvent being supplied to said first container,

(h) and control means for controlling said valve means,

said control means including sensing duct means interconnecting the air stream conveying means and said sump means in a manner to draw therethrough a stream of vapor from above said predetermined level of dry cleaning solvent in said sump means for sampling the relative humidity of the dry cleaning solvent in said sump means, means in relative humidity sensing relationship to said stream of vapor for effecting a control signal in response to the relative humidity sensed, and means for processing said control signal in a manner to open said valve means when the relative humidity of said stream of vapor is below a predetermined value.

4. In combination,

(a) means forming a container adapted to contain a dry cleaning solvent such as perchlorethylene or the like for dry cleaning clothes,

(b) means for conveying a stream of air over the clothes after dry cleaning thereof for drying the clothes,

(0) means forming a substantially closed sump means containing a predetermined level of dry cleaning solvent therein,

(d) duct means interconnecting the air stream conveying means with the sump means in a manner to draw therethrough a stream of vapor from above said predetermined level of dry cleaning solvent in said sump means for sampling the relative humidity of the dry cleaning solvent in said sump means,

(e) means including a solvent supply conduit con nected in supply relationship to said container for effecting the circulation of dry cleaning solvent between said sump means and said container,

(f) means for entraining water into the dry cleaning solvent being supplied to said container including a venturi in said solvent supply conduit having a suction inlet, a water supply conduit having one end connected to a supply of water and its other end connected to said suction inlet, and valve means in said water supply conduit openable for passing a regulated amount of water to said suction inlet for subsequent entrainment through said venturi into the dry cleaning solvent being supplied to said container,

(g) and control means responsive to the relative humidity of the stream of vapor in said duct means for controlling said valve means.

5. In combination,

(a) means forming a container adapted to contain a dry cleaning solvent such as perchloroethylene or the like for dry cleaning clothes,

(c) means forming a substantially closed sump means containing a predetermined level of dry cleaning solvent therein usable in said container,

((1) duct means interconnecting the air stream conveying means with the sump means in a manner to draw therethrough a stream of vapor from above said predetermined level of dry cleaning solvent in said sump means for sampling the relative humidity of the dry cleaning solvent in said sump means,

(e) means for supplying water to the dry cleaning solvent before it is used in said container including valve means openable for passing a regulated amount of water to the dry cleaning solvent,

(f) and control means responsive to the relative humidity of the stream of vapor in said duct means for controlling said valve means.

6. In combination,

(a) means forming a container adapted to contain a dry cleaning solvent such as perchlorethylene or the like for dry cleaning clothes therein,

(b) means energizable for agitating the clothes in said container,

(c) means forming a substantially closed sump means containing a predetermined levelof dry cleaning solvent therein usable in said container,

(d) duct means connected with the sump means in a manner to convey therethrough a stream of vapor from above said predetermined level of dry cleaning solvent in said sump means for sampling the relative humidity of the dry cleaning solvent in said sump means,

(e) means for supplying Water to the dry cleaning solvent including valve means openable for passing a regulated amount of Water to the dry cleaning solvent only when said agitating means is energized,

(f) and control means responsive to the relative humidity of the stream of vapor in said duct means and including means energizable in response to the energization of said agitating means for controlling said valve means.

7. In combination,

(b) means for conveying a stream of air for removing solvent fumes resulting from said dry cleaning,

(e) means for supplying Water to the dry cleaning solvent before it is used in said container including means operable for passing a regulated amount of Water to the dry cleaning solvent,

(f) and control means responsive to the relative humidity of the stream of vapor in said duct means for controlling said means for passing water.

References Cited by the Examiner UNITED STATES PATENTS 2,967,084- 1/61 Reitz 68207 X 3,066,519 12/ 62 Boswinkle et al 5818.1 X 3,093,442 6/63 Brown et al. 68l3 X WALTER A. SCHEEL, Primary Examiner.

WILLIAM I. PRICE, Examiner.

Claims

7. IN COMBINATION, (A) MEANS FORMING A CONTAINER ADAPTED TO CONTAIN A DRY CLEANING SOLVENT SUCH A PERCHLORETHYLENE OR THE LIKE FOR DRY CLEANING CLOTHES, (B) MEANS FOR CONVEYING A STREAM OF AIR FOR REMOVING SOLVENT FUMES RESULTING FROM SAID DRY CLEANING, (C) MEANS FORMING A SUBSTANTIALLY CLOSED SUMP MEANS CONTAINING A PREDETERMINED LEVEL OF DRY CLEANING SOLVENT THEREIN USABLE IN SAID CONTAINER, (D) DUCT MEANS INTERCONNECTING THE AIR STREAM CONVEYING MEANS WITH THE SUMP MEANS IN A MANNER TO DRAW THERETHROUGH A STREAM OF VAPOR FROM ABOVE SAID PREDETERMINED LEVEL OF DRY CLEANING SOLVENT IN SAID SUMP MEANS FOR SAMPLING THE RELATIVE HUMIDITY OF THE DRY CLEANING SOLVENT IN SAID SUMP MEANS, (E) MEANS FOR SUPPLYING WATER TO THE DRY CLEANING SOLVENT BEFORE IT IS USED IN SAID CONTAINER INCLUDING MEANS OPERABLE FOR PASSING A REGULATED AMOUNT OF WATER TO THE DRY CLEANING SOLVENT.