US3683944A

US3683944A - Control apparatus for washer-sterilizer

Info

Publication number: US3683944A
Application number: US109175A
Authority: US
Inventors: Edgar L Anderson; Michael L Schneier
Original assignee: Sybron Corp
Current assignee: MDT Corp; Raytheon Co
Priority date: 1971-01-25
Filing date: 1971-01-25
Publication date: 1972-08-15
Anticipated expiration: 1989-08-15
Also published as: GB1320883A; JPS534354B1; CA935068A; DE2202668A1

Abstract

Disclosed is a washer-sterilizer apparatus having a water reservoir which supplies both the wash and rinse water and two pumps, one pump for pumping water from the reservoir for filling and rinsing and another for recirculating water in the washersterilizer during the wash cycle and draining. The reservoir is heated after filling to provide rinse water at a temperature higher than the wash water temperature. The apparatus controls are completely automatic and may be integrated with controls for loading and unloading devices to provide a completely automated system.

Description

United States Patent Anderson et al.

[ CONTROL APPARATUS FOR WASHER- STERILIZER [72] Inventors: Edgar L. Anderson, Penfield; Michael L. Schneier, Pittsford, both of NY.

[73] Assignee: Sybron Corporation, Rochester,

[58] Field of Search ..l34/57 R, 57 D, 57 DL, 95, 134/99, 100,101,103, 72, 68,131,134;

[151, 3,683,944 1451 Aug. 15,1972

2,197,382 Murphy ..134/95 x 2,621,666 12/1952 Hiort AfOrnas ..134/57 1) 2,859,760 11/1958 Borell ..134/57 ox 3,221,754 12/1965 Robson et a1 ..l34/68 Primary Examiner-Walter A. Scheel Assistant Examiner-Philip R. Coe Attorney-Theodore B. Roessel 2 ABSTRACT Disclosed is a washer-sterilizer apparatus having a water reservoir which supplies both the wash and rinse water and two pumps, one pump for pumping water from the reservoir for filling and rinsing and another a for recirculating water in the washer-sterilizer during the wash cycle and draining. The reservoir is heated after filling to provide rinse water at a temperature 68/ 12 R higher than the wash water temperature. The apparatus controls are completely automatic and may be [56] Reierences cued integrated with controls for loading and unloading UNI STATES PATENTS devices to provide a completely automated system.

3,049,133 8/1962 Jacobs ..l34/57 D 10 Claims,'2 Drawing Figures STEAM Patented Aug. 15, 1972 N B m mm m R w w v m m L Du A G D m E mm 1 9 i Q t mm a l e h 4 m 8 av M ON 5 2 Nbj a %x E I $2; W J N- um ow( A m- N- w 2E5 mm F mm lwwl -65:

BY MICHAEL LSCHNEIER H OI ATTORNEY CONTROL APPARATUS FOR WASHER- STERILIZER BACKGROUND OF THE INVENTION The present invention relates to a washer-sterilizer apparatus particularly for use by pharmaceutical manufacturers, hospitals, laboratories and the like. Specifically, the invention relates to a washer-sterilizer having a water reservoir from which is drawn the wash and rinse water. The water in the reservoir is temperature controlled to provide optimum washing and rinsing temperatures. The controls for regulating the temperature of the water in the reservoir are integrated with both the controls for operating the washer-sterilizer, and the loader and unloader controls thereby providing a fully automated system.

Prior art washer-sterilizer units which drew wash and rinse water directly from the buildings water supply had several drawbacks including a long fill cycle in areas of low water pressure. Since the fill cycle depended upon the water pressure in the building, the length of the till cycle might vary as the water pressure varied. This required an additional control function to compensate for this varying fill time. Further, since the unit was connected to the water supply of the building, the temperature of the wash and rinse cycles were dependent upon the temperature of this water supply.

The present invention provides a separate reservoir tank associated with the washer-sterilizer including a pump for drawing water from the reservoir and a water reservoir temperature control. With this arrangement, the till time and water temperature are not sensitive to the pressure and temperature of thebuilding water supply. For example, the fill cycle does not depend upon line pressure in the building but filling to a desired level may be accomplished quickly and accurately by pumping water from the reservoir into the washing apparatus. The temperature of water in the reservoir can be varied between the wash and rinse cycles to provide gradually increasing temperatures during the wash cycle and a high temperature rinse cycle. This gradual temperature increase to the eventual hot water rinse is particularly useful to prevent protein material from cooking-on the articles being washed. When steam is used during the sterilizing cycle, controls are provided for utilizing the steam to control the water temperature during the wash and rinse portion of the operating cycle.

SUMMARY OF THE PRESENT INVENTION The present invention may be characterized in one aspect thereof by the provision of a water reservoir associated with the washer-sterilizer apparatus; a first pump for pumping water from the reservoir into the washer sterilizer for filling and rinsing; a second pump for recirculating the water during washing and for draining; and control means including a water temperature controller, said control means being integrated with control for the washer-sterilizer loading and unloading apparatus to provide a fully automated system.

OBJECTS OF THE INVENTION An object of the present invention is to provide a washer-sterilizer having a ready supply of both wash and rinse water at a controlled temperature wherein operation of the apparatus is not sensitive to the normal building water supply as to temperature, pressure or rate of flow.

A further object of the present invention is to provide a washer-sterilizer having means for filling the washing chamber with wash water quickly and accurately independent of the line pressure.

Yet another object of the present invention is to provide a washer sterilizer and an associated water reservoir having integrated controls for operating the washer sterilizer and controlling the temperature of the water in the reservoir.

Still another object of the present invention is to pro: vide a washer-sterilizer having controls which may be integrated with the controls of an automatic loader-underloader provide a fully automated system.

Yet another object of the present invention is to provide a washer-sterilizer apparatus which has an optimum size pump for filling and rinsing and a second, larger, pump for recirculating the water during washing and then draining.

These and other objects, advantages and characterizing features of the present invention will become more apparent upon consideration of the following detailed description thereof when taken in connection with the accompanying drawings depicting the same.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view of the washer sterilizer apparatus of the present invention; and

FIG. 2 is a block diagram of the control circuit of the washer sterilizer of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawing, FIG. 1 shows the washersterilizing vessel generally indicated at 10. The vessel is preferably of the type which allows pass-through operation, that is, it has a loading door 12 at one end of a vessel chamber 8 and an unloading door 14 at another end of the vessel chamber. These doors may be operated by means (not shown) to slide the doors over the load and unload openings of chamber 8. Appropriate limit switches as shown in the schematic of FIG. 2 are provided at both the load and unload doors to indicate when the doors are fully open or closed. Suitable load and unload mechanism represented schematically by

conveyors

16 and 18 respectively are provided for passing the articles to be washed and sterilized into and out of the vessel.- It should be understood that

conveyors

16 and 18 only schematically represent the mechanisms for passing the articles to be washed and sterilized into and through vessel 10. These articles, in the case of hospital operation, may be such things as operating room instruments and apparatus, patient room equipment, bed pans trays, dishes or the like. Such items usually are contaminated with some sort of protein material which must be kept from cookingon during the washing and sterilizing cycles. Accordingly, such. articles are usually washed with water at one temperature to prevent coagulation of protein and then rinsed with water at a higher temperature before sterilizing.

In order to provide accurate controlof the wash and rinse water temperatures, a reservoir tank 20 is provided for storing the water used during the wash and rinse cycles. This reservoir is connected to and filled from the normal water supply of the building by main line 22 and pipe 24. A solenoid valve SV-4 controls flow through pipe 24. The reservoir is also provided with two temperature sensors and a liquid level controller TS-2, TS-3, and LLC-2 respectively which operate in the manner described hereinbelow.

Water is pumped from reservoir 20 through a pipe 26 by a fill pump 28 which has its outlet side connected by means of

pipes

30 and 32 to various spray headers 34 located with chamber 8. A level controller LLC-l determines the amount of wash water pumped into the chamber. The outlet of pump 28 is also connected to an aspirator 36 for introducing detergent from a detergent tank 38 into line 30. Flow of the detergent is turned on and off by the operation of a solenoid valve SV- which lies in line 40 connecting the outlet of the pump to the aspirator and line 30.

Vessel has a sump portion 42 which is connected by a pipe 44 to the inlet of a recirculating pump 46. The outlet of recirculating pump 46 is connected to a Y- strainer 48. Y-strainer 48 has one branch 48 (a) connected to pipe 50 which in turn is connected to lines 32 for purposes. of recirculating the wash water within chamber 8 during the wash cycle. Pipe 50 is provided with a temperature sensor TS-l which monitors the temperature of the recirculating water for purposes set out hereinbelow. The other branch 48(1)) of the Y- strainer is connected by a drain pipe 52 to a waste drain 54. Drain pipe 52 is opened and closed by a solenoid valve SV-l.

The sterilizing cycle of operation is accomplished with steam wherein the steam is not only used for sterilizing but also for heating the water in reservoir tank and for sealing the load and unload

doors

12 and 14 of the washer-sterilizer vessel. To accomplish this, a main steam supply line 56 which is connected to a steam source (not shown) has one branch line 58 connected to water reservoir 20. A solenoid valve SV-3 in branch 58 controls the flow of steam to the reservoir. A second branch line 60 is connected to the washer sterilizer vessel 10 and opens into chamber 8. A solenoid valve SV-2 in branch line 60 and operated by a temperature sensor TS-4 controls the flow of steam to the chamber of the washer-sterilizer. A third branch line 62 is connected by means of pipes 62(a) and (b) to' the load and

unload door seals

64 and 66 respectively. The particular operation of these seals will not be described in detail here as they are more particularly described in a co-pending application, Ser. No. 32,284. It is sufficient for purposes of the present invention merely to say that when steam issupplied to the seals, gaskets are moved into position to seal the doors against the chamber openings. A cam operated valve V-l opens and closes branch line 62 wherein this cam valve is operated by a drive motor 68.

A steam exhaust line 72 "which is connected to branch line 62 is opened and closed by a cam valve V-3 also operated by drive motor 68 to vent steam from

seals

64 and 66 so that the load and unload doors can be opened. Steam exhaust line 72 is connected to a water ejector 74, the water ejector in turn being connected by pipe 76 to the main water supply line 22. A cam valve V-2 also operated by drive motor 68 opens and closes this water line to the ejector.

Completing the connections to the washer-sterilizer is a chamber vent pipe 70 and a branch water line 78. Chamber vent pipe 70 which communicates with chamber 8 through line 60 is opened and closed by a cam valve V-S. Water branch line 78 is connected to a coil 80 located in sump 42 for purposes of circulating water through the sump to cool and collapse the steam within chamber 8 at the end of the sterilizing cycle. A

vacuum switch VS-l provided for purposes set out hereinbelow indicates when a predetermined vacuum is drawn in chamber 8 by the collapsing steam.

Line 78 is opened and closed by a cam valve V-4 operated by drive motor 68 with water from the coil being discharged through line 82 to drain 54. Two

additional drail lines

84 and 86 extend from sump 42 to drain. These drain lines 84 and 86 are opened and closed by solenoid valves SV-9 and SV-6 respectively. One of the drain lines, 84, is connected to ejector 74.

FIG. 2 shows in block diagram form the various circuits for controlling the operation of the washer-sterilizer. These circuits are opened or closed by various cam switches (CS) operated by drive motor 68 as described hereinbelow. While not shown, it should be understood that each cam switch has an open and a closed contact so' that certain of the switches may actuate one circuit when open and another when closed.

The main power on-off switch has not been shown for purposes of simplifying the description of the operation and it is understood that power must be on in order to energize the controls shown in FIG. 2. Various safety devices which can shut down operation at any point in the cycle have also, been not shown, in order to simplify the description.

Referring to FIGS. 1 and 2, the operation will be described as beginning with the unload 14 door closed and load door 12 open; indexing motor 68 in the off position; and the articles to be washed and sterilized ready for loading into vessel 10 by load conveyor 16. In this position,limit switches on the load door, which are in a condition indicating that load door 12 is fully open, delivers power to the loader circuit which in turn operates the loading mechanism represented by conveyor l6.

While the vessel is being loaded, the level and temperature of the water is reservoir 20 is adjusted by power through CS-S (NC). In this respect, water level sensor LLC-2 may close a circuit to open solenoid SV- 4 to admit water to the reservoir while a circuit through cam switches CS5 and CS-7 acting through temperature sensor TS-2 operates solenoid SV-3 to admit steam into the reservoir as necessary to bring the water to wash temperature.

When loading is complete, a feed back from the load conveyor drive through the loader circuit (FIG. 2) activates the load door motor to close load door 12. When the load door is closed, power is delivered by the limit switches (now indicating that the load door is closed) to the drive circuit of motor 68 to index the drive motor to the second or wash position. At this wash position, cam switch CS-l is actuated, cam switch CS-7 is deactuated and connected to temperature sensor TS-3 and cam valve V-l is opened.

Connecting CS-8 to temperature sensor TS-3 causes solenoid SV-3 to open to introduce steam into reservoir 20 for bringing the reservoir water up to rinse temperature.

Opening V-l admits steam to he gaskets of seals 64 and 66 (FIG. 1) to seal the load and unload doors against the vessel.

Actuating cam switch CS-l completes a circuit through the liquid level controller LLC-1 to start fill pump 28 and open solenoid SV-S. Solenoid SV-S is opened to permit a portion of the water from the pump outlet to flow through line 40 and aspirator 36. This draws liquid detergent from liquid detergent container 38 and mixes detergent with the fill water flowing into the vessel through

line

30 and 32. Pump 28 continues to operate until LLC-1 is satisfiedie. the water in vessel chamber 8 reaches the desired level. When this occurs, the circuit through LLC-l to fill pump 28 and'SV- 5 is opened to stop the fill motor and close the detergent solenoid SV-S. When LLC-l is satisfied, another circuit is closed through LLC-l to start recirculating pump 46. The recirculating pump pumps the water-de tergent mixture from sump 42 through line 44, Y- strainer branch 48(a),

lines

50 and 32 into the vessel through spray headers 34. The recirculating pump has a higher power rating than filling pump 28 so that the water detergent mixture is sprayed with considerable force through spray headers 34 to wash the articles within the vessel.

The temperature of the recirculating water detergent mixture is monitored by temperature sensor TS-l in line 50. This temperature sensor is connected to solenoid valve SV-2 and operates to open or close SV-2 to introduce steam into the vessel as necessary to maintain the proper washing temperature. While the articles are being washed, LLC-2 opens SV-4 so that reservoir tank 20 is refilled.

When recirculating pump 46 is started, a wash timer TR-l is also started. At the end of the timed wash period, the timing out of timer TR-l overrides TS-l and deenergizes SV-2. Also, when TR-l times out, a circuit is made through a drain time delay relay TDR-l to drain solenoid valves SV-l and SV-6 to open the

drain lines

52 and 86. With drain solenoid SV-l opened, continued operation of recirculating pump 46 will now direct the water detergent mixture through arm 48(b) of the Y-strainer and line 52 to waste drain 54. This also cleans the drain screen 48(c). Screen 48(c) which lies across arm 48(a) prevents the circulation of solid material washed from the articles in chamber 8 back to the chamber. However, the screen is arranged so that as water is flowing to drain, the screen is cleaned and the solid material collected on the screen also flushed to the drain. Solenoid valve SV-6 is also opened to assist in the draining of the water detergent mixture from sump 42 through line 86.

When time delay relay TDR-l times out, the motor drive circuit is actuated to index the motor to the third or rinse positionfTWhen the motor is indexed to the rinse position, cam switches CS-2 and CS-4 are actuated. Actuating cam switch CS-2 opens solenoid SV-2; starts a rinse time delay relay TDR-Z to time the rinse cycle; and arms a circuit which is capable of delivering power to fill pump 28. Actuating CS-4 completes a circuit to a pulse timer circuit which delivers power to a pulse motor. Operation of the pulse motor opens and closes a switch in the armed" fill pump circuit to start fill pump 28. In this manner, fill pump 28 is operated intermittently to spray water through headers 34 in pulses which increases the effectiveness of the rinsing operation. During this rinse period, solenoid valves SV- 1 and SV-6 are held open by a circuit through CS-4 so that the rinse water is flushed to the waste drain.

With solenoid SV-2 open steam is introduced into chamber 8 through line 60 which helps to push the rinse water out through the open. drains 52 and 86. At the end of the rinse period, TDR-2 times out causing motor 68 to index to the fourth or sterilizing position. As the motor is indexed to the sterilizing position, CS-2 and CS4 are deactuated to open the circuit to fill pump 28, the pulse timer and solenoid valves SV-l and S At the sterilizing position, motor 68 operates to open cam valve V-2 and cam switch CS-S and close cam switches CS-9. With valve V-2 opened, water flows through lines 22 and 76 through ejector 74. Power through CS-10 (N.C.) opens solenoid valve SV-9 so that the water flowing through ejector 74 can pull any condensate and air from vessel 10 and discharge it to the waste drain 54. A trap 87 in line 84 prevents the escape of steam but allows the passage of condensate to the waste drain. In this manner, condensed steam is continuously removed from the vessel throughout the sterilizing cycle. Closing cam switch CS-9 completes a circuit through contact (a) of a dual contact tempera ture sensor TS-4 to steam solenoid valve SV-2 and opening CS-S breaks the circuit to SV-3 so that all available steam is directed into vessel 10. When the sterilizing temperature is reached, contact (12) of temperature switch T84 is closed to start a sterilize time delay relay TDR-3 which times the sterilizing cycle. Temperature switch TS-4 continues to operate through contact (a) to open or close SV-2 for adding steam as necessary to maintain the sterilizing temperature.

At theend of timed sterilizing cycle, TDR-3 closes the motor drive circuit to index motor 68 to the fifth or evacuate position. As motor 68 indexes to the evacuate position, cam switches CS6 and CS-9 are deactuated, CS-10 actuated and cam valve V4 is opened. Deactuating CS-9 causes steam solenoid SV-Z to close while opening valve V-4 allows water to circulate through coil 80 to collapse the steam in the vessel chamber 8. Actuating cam switch CS-l0 holds solenoid SV 9 open through the evacuate cycle. When a predetermined vacuum is drawn in the vessel chamber 8 by collapsing the steam, a vacuum switch VS-l closes to start motor 68 indexing through the sixth or vent position to the seventh or cycle complete" position.

In the vent position, cam valve V-2 remains open to continue flow of water to the ejector. Also, in the vent position, cam valve V4 is closed; cam valve V-3 is opened to vent steam from

gaskets

64 and 66 and unseal the load and unload doors; and cam valve V-5 is opened to vent chamber 8 to bring the chamber back to atmospheric pressure.

As motor 68 indexes to the cycle complete" position, cam switch CS-ll is actuated to energize the un loader circuit. The unloader circuit first starts the unload door motor to open the unload door 14. When the unload door is full open, the unloader circuit causes the motor drive circuit to close to begin indexing motor 68 to the off position. In moving to the off position, CS- 1 1 is deactuated, however, the unloader circuit remains powered by a circuit through limit switches at the unload door which indicate that the unload door is full open. Thus, the unloader circuit continues to function to power the unload mechanism represented by unload conveyor 18 to unload the washed and sterilized aiticles. When the unload cycle is complete, a feedback from the unload conveyor drive through the unloader circuit activates the door closing mechanism. When the unload door is closed, the limit switch associated with the unload door delivers power through the load door limit switches and load circuit to open the load door to begin the loading cycle.

Accordingly, it should by appreciated that the present invention accomplishes its intended objects in providing a washer-sterilizer having a ready supply of bath wash and rinse water at the proper temperature. The use of two separate pumps, one for filling and rinsing, and another, larger pump for washing provides an efficient means of performing these functions. Further efficiency is gained by employing the sterilizing medium, steam, to perform other functions such as heating the reservoir water, maintaining the proper wash temperature and assisting in the removal of water from the vessel and by integrating the washer-sterilizer controls with the loader and unloader controls to provide a fully automated system.

While a preferred embodiment of the present invention has been described, it should be appreciated that various modifications are within the skill of the art. For example, another reservoir, reservoir water controls, a second fill pump and appropriate controls may be in corporated into the present design to provide a distill water or other special rinse which would be employed after the normal rinse occurring at the third position.

Having thus described the invention, what is claimed as new is:

l. Washer apparatus comprising in combination:

a. a closed vessel having an opening therein for receiving the articles to be washed including means for closing and sealing said opening;

b. a water reservoir tank having a water level and temperature control means;

cfa conduit connecting said water reservoir tank to said vessel and terminating in a plurality of spray nozzles within said vessel;

. a first fill pump for pumping water from said water reservoir tank through said conduit and into said vessel;

e. a second recirculating pump having its inlet and outlet communicating with said vessel for recirculating the water in said vessel to wash the articles therein;

f. an electric circuit having a first portion operatively connected to said fill pump and a second portion operatively connected to said recirculating pump;

. a water fill control means in said vessel for opening said first circuit portion and closing said second circuit portion when the water in said vessel reaches a predetermined level; and means in said electric circuit for disabling said fill control means when said circuit to said recirculating pump is closed.

2. Apparatus as set forth in claim 1 including rinse control means for rinsing said articles after a predeter- -mined timed wash interval, said rinse control means comprising: i

a. a first electric including said fill pump;

b. a second electric circuit including a pulse timer for opening and closing said first circuit including a pulse timer for opening and closing said first circuit to cycle said fill pump on and off for predetermined timed intervals; and

c. a timer for deenergizing said first and second circuit after a predetemlined timed rinse interval.

3. Apparatus as set forth in claim 2 comprising means for heating the water in said reservoir prior to operation of said rinse control means whereby water from said reservoir used during rinsing is at a higher temperature than water from said reservoir used during washing.

4. Washer-sterilizer apparatus and controls therefore comprising:

a. a closed vessel having an opening therein for receiving the articles to be washed and sterilized including means for closing and sealing said openmg;

b. a water reservoir tank exterior of said vessel having a reservoir water level and temperature control means, said reservoir supplying water to said vessel for washing and rinsing said articles;

c. a conduit connecting said reservoir and said vessel;

d. a first, fill pump for pumping water from said reservoir through said conduit and into said vessel;

e. a second, recirculating pump for recirculating water in said vessel to wash said articles;

f. a first electric circuit including water level control means for stopping said fill pump and starting said recirculating pump when the water level in said vessel has reached a predetermined level and a timer for opening said electric circuit after said recirculating pump has operated for a timed wash period; and

. a second electric circuit including means for introducing a sterilizing medium into said vessel and a timer for opening said second circuit after a predetermined timed sterilizing interval, said second electrical circuit being initially closed after said first circuit is opened.

5. Apparatus as set forth in claim 4 comprising:

a. a third electric circuit including said fill pump;

b. a fourth electric circuit including a pulse timer for opening and closing said third circuit to cycle said fill pump on and off to rinse said articles;

c. means activating said third and fourth circuits after said first circuit is opened; and

d. a rinse timer in said third circuit adapted to open said third and fourth circuits after a predetermined timed rinse period.

6. Apparatus as set forth in claim 4 wherein said sterilizing medium is steam, said apparatus further comprising:

a. a valved steam conduit connecting said vessel to a source of steam;

b. a valved branch line extending from said steam conduit into said reservoir tank; and

c. said reservoir water level and temperature control means being operatively connected to said branch line valve to open and close the same responsive to the temperature of water in said reservoir.

7. Apparatus as set forth in claim 6 wherein said means for closing and sealing said vessel opening comprises:

a. a steam operated seal;

b. a second valved branch line connecting said steam conduit to said steam operated seal; and

c. means for opening said second branch line to effect said seal.

8. Apparatus as set forth in claim 4 comprising: I

a. said vessel having said load opening at one end thereof and an unload opening at an opposite end;

b. limit switches associated with said load and unload openings for indicating when said openings are full open and full closed; I

c. loader means adjacent said load opening and unloader means adjacent said unload opening for moving said articles into and out of said vessel; and

d. a third electric circuit including said limit switches and loader and unloader means, said electric cir cuit having a first portion activating said loader means when said load opening is full open and a second portion activating said unloader means when said unload opening is full open.

9. Apparatus as set forth in claim 8, wherein said 10. A washing and sterilizing apparatus having a wash cycle, a rinse cycle and a sterilizing cycle, comprising in combination:

a. a vessel having a load opening at one end thereof and an unload opening at an opposite end to persaid wash cycle and thereafter for said rinse cycle and said second pump for recirculating water in said vessel during said wash cycle;

f. means for controlling the operation of said pumps during said wash and rinse cycles;

g. means for introducing steam into said vessel during said sterilizing cycle;

h. loader means adjacent said loadopening and unloader means adjacent said unload opening for moving articles into and out of said vessel; and

i. an electric circuit including said limit switches, loader means and unloader means, said circuit having a first portion activating said loader means when said load opening is full open and the second portion activating said unloader means when said unload opening is full open.

@ 3 3 UNITED STATES PATENT ormcE CE'NFKCATE OF C ECTION Patent No. 3, 3,9 Dated August 15, 1972 Inventor-( Edgar L. Anderson and Michael L. Schneier It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 2, line 16 after "deloader" insert --to-. Column line 45 "is" first instance should read -to--. Column 5, line 1 "he" should read -the-. Column 7, line 66 after "electric" insert --circuit,.

Column 8, line 2- cancel "including a pulse timer for opening and closing said first circuit".

Signed and sealed this 20th day of March 1973.

(SEAL) Attest:

V EDWARD M@FLETCHER,JR., Y ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents

Claims

1. Washer apparatus comprising in combination: a. a closed vessel having an opening therein for receiving the articles to be washed including means for closing and sealing said opening; b. a water reservoir tank having a water level and temperature control means; c. a conduit connecting said water reservoir tank to said vessel and terminating in a plurality of spray nozzles within said vessel; d. a first fill pump for pumping water from said water reservoir tank through said conduit and into said vessel; e. a second recirculating pump having its inlet and outlet communicating with said vessel for recirculating the water in said vessel to wash the articles therein; f. an electric circuit having a first portion operatively connected to said fill pump and a second portion operatively connected to said recirculating pump; g. a water fill control means in said vessel for opening said first circuit portion and closing said second circuit portion when the water in said vessel reaches a predetermined level; and h. means in said electric circuit for disabling said fill control means when said circuit to said recirculating pump is closed.

2. Apparatus as set forth in claim 1 including rinse control means for rinsing said articles after a predetermined timed wash interval, said rinse control means comprising: a. a first electric including said fill pump; b. a second electric circuit including a pulse timer for opening and closing said first circuit including a pulse timer for opening and closing said first circuit to cycle said fill pump on and off for predetermined timed intervals; and c. a timer for deenergizing said first and second circuit after a predetermined timed rinse interval.

4. Washer-sterilizer apparatus and controls therefore comprising: a. a closed vessel having an opening therein for receiving the articles to be washed and sterilized including means for closing and sealing said opening; b. a water reservoir tank exterior of said vessel having a reservoir water level and temperature control means, said reservoir supplying water to said vessel for washing and rinsing said articles; c. a conduit connecting said reservoir and said vessel; d. a first, fill pump for pumping water from said reservoir through said conduit and into said vessel; e. a second, recirculating pump for recirculating water in said vessel to wash said articles; f. a first electric circuit including water level control means for stopping said fill pump and starting said recirculating pump when the water level in said vessel has reached a predetermined level and a timer for opening said electric circuit after said recirculating pump has operated for a timed wash period; and g. a second electric circuit including means for introducing a sterilizing medium into said vessel and a timer for opening said second circuit after a predetermined timed sterilizing interval, said second electrical circuit being initially closed after said first circuit is opened.

5. Apparatus as set forth in claim 4 comprising: a. a third electric circuit including said fill pump; b. a fourth electric circuit including a pulse timer for opening and closing said third circuit to cycle said fill pump on and off to rinse said articles; c. means activating said third and fourth circuits after said first circuit is opened; and d. a rinse timer in said third circuit adapted to open said third and fourth circuits after a predetermined timed rinse period.

6. Apparatus as set forth in claim 4 wherein said sterilizing medium is steam, said apparatus further comprising: a. a valved steam conduit connecting said vessel to a source of steam; b. a valved branch line extending from said steam conduit into said reservoir tank; and c. said reservoir water level and temperature control means being operatively connected to said branch line valve to open and close the same responsive to the temperature of water in said reservoir.

7. Apparatus as set forth in claim 6 wherein said means for closing and sealing said vessel opening comprises: a. a steam operated seal; b. a second valved branch line connecting said steam conduit to said steam operated seal; and c. means for opening said second branch line to effect said seal.

8. Apparatus as set forth in claim 4 comprising: a. said vessel having said load opening at one end thereof and an unload opening at an opposite end; b. Limit switches associated with said load and unload openings for indicating when said openings are full open and full closed; c. loader means adjacent said load opening and unloader means adjacent said unload opening for moving said articles into and out of said vessel; and d. a third electric circuit including said limit switches and loader and unloader means, said electric circuit having a first portion activating said loader means when said load opening is full open and a second portion activating said unloader means when said unload opening is full open.

9. Apparatus as set forth in claim 8, wherein said third circuit operates to close said first circuit after said limit switches indicate that said load and unload openings are closed, said third circuit in turn being operated to open said unload opening after said second circuit is opened.

10. A washing and sterilizing apparatus having a wash cycle, a rinse cycle and a sterilizing cycle, comprising in combination: a. a vessel having a load opening at one end thereof and an unload opening at an opposite end to permit movement of articles into, through and out of said vessel; b. means for closing and sealing said openings; c. limit switches associated with said load and unload openings for indicating when said openings are fully open and fully closed; d. a reservoir tank for supplying wash and rinse water to said vessel, said tank including means for controlling the level and temperature of the water therein; e. first and second pumps, said first pump for pumping water from said reservoir into said vessel for said wash cycle and thereafter for said rinse cycle and said second pump for recirculating water in said vessel during said wash cycle; f. means for controlling the operation of said pumps during said wash and rinse cycles; g. means for introducing steam into said vessel during said sterilizing cycle; h. loader means adjacent said load opening and unloader means adjacent said unload opening for moving articles into and out of said vessel; and i. an electric circuit including said limit switches, loader means and unloader means, said circuit having a first portion activating said loader means when said load opening is full open and the second portion activating said unloader means when said unload opening is full open.