US2605969A - Apparatus for processing canned foods and the like - Google Patents

Description

Aug. 5, 1952 c. w. SANDERS APPARATUS FOR PROCESSING. CANNED FOODS AND THE LIKE Filed Dec. 31. 1949 mmbzs Ema w +2m INVENTOR. mm. w. SANDERS ATTORNEY Patented Aug. 5, 1952 UNITED STATES PATENT I E A PARATUS- FOR PnooEssING oqNNnD FOODS AND THE LIKE 1 Carl W. Sanders, Rochester, N. Y assignor to Taylor Instrument Companies, Rochester, N. Y a corporation ofN-ew York Application December 31, 1949, Serial N 0. 136,261 (o1. ass-4 3 Claims. 1 1 This invention relates to apparatus for processing canned foods and the like.

' In the sterilization of canned foods in retorts where steam is used as the heating medium, it

is essential that the retorts be completely free from air at the beginning of each processing cycle. Otherwise, improperly sterilized canned goods may result with consequent spoilage thereof.

In accordance with the present invention, there is provided a novel system whereby at the beginning of each cycle, the-retort will be automatically vented'to the atmosphere until two conditions have been satisfied,- namely the existence of a predetermined temperature in the retort and the passing of a given time interval. For a clearer understanding of the invention reference is made to the following description and claims when taken with the drawing in which Fig. 1 illustrates a wellknown canners retort and auxiliary temperature and pressure control equipment together with pneumatic and electric circuits'shown in diagrammatic form; and Fig. 2 is a detail view of the air supply valve in'its open position. 7 Y I In the drawings, the numeral designates a well-known type of canners retort open at its top but having a cover 6 which can be removably sealed in position by the clamping bolts I mounted on the rim of the retort. These bolts engage notches in the ed of the cover, and cooperate with the butterfly nuts 8 to clamp the cover in the position illustrated. The retort is heated by steam supplied through pipe 9'to the upper part thereof, under the control of a dia- Dhragm motor valve l0. which is opened by the application of compressed air to its motor.

The. r tor s p ded o i side h a communicating chamber ll into which there extends the thermosensitive bulb l2 of a tempfit ature controller T and with which chamber there also communicates. the pressure measuring pipe l3 of 'a'rpressure controller P. The temperature controller I and the pressure, controller P are effective. to maintain a given temperature and a givenpressure within theretortduring predetermined portions'of the. processing cycle. ,Although the-chamber communicates with the interior of the retort, the heating steam in this chamber tends to become stagnant and therefore would not provide an accurate sample of the temperatureconditions in the retort. flicr this reason the chamber is-provided with a bleed pipe to the atmosphere controlled by albleed v alve .14 of the diaphragm motor type, whichis closed .ing cycle.

. 2. by the application of compressed air to its motor. As will be pointed out, this bleedvalve is open to the atmosphere duringthe cooking portion of the. process. cycle to insure circulation of the steam in the. chamber and to purge noncondensables from the chamber during the cooking cycle. The bottom of theretort is likewise provided with a, pipe 16 controlled by the bleed valve I! of the. diaphragm motor type. This valve which is closed when compressed air is applied'lto its motor,- is maintained open during the cooking portion of the process cycle so that sufficient steam can bleed fromthe pipe 16, to vent noncondensables that may be introduced during cooking period. A pipe I8 having the hand valve l9 thereon, communicates with the bottom of the retort to supply cooling water at the end of the cooking period.

It is essential that a uniform given pressure prevail in the retort especially during the cool- -To this end, the retort can be supplied with compressed vair through pipe 2| under the control of the motor valve 22. It should be pointed out that valve 22 comprises two superimposed diaphragm motors either of which is operated by compressed, air at a, pressure of from one to, nine pounds per square inch, tending to throttle this valve.

An overflow pipe 23 leading to the ,top of the retort, is throttled -to=,its opfin position when compressed air at'a pressure of ten to eighteen pounds per Square inch is'applied to the'top of the motor valve 24, under control of themessure controller P. A hand valve 25 in a branch of drain pipe 23 is closed when thepressurein the retortis to be automatically controlled, but serves toprovide manual control of this pressure whenso desired. A well-known safety valve 21 isproyided near'the top of the retort to open into a branch-28 of the drain pipe-23 and thereby relieve abnormalpressures in the-retort.

In order to insurethat the interior of the retort is completely free from air, the bottom of the retort-has-azvent pipe 29 'whichis opened by a diaphragm -motor valve 30 until compressed air is applied to the valve motor. l I T The system utilizes a process timer tocontrol A the duration er the cooking portion-of the cycle.

ljhi-s timercomprises the synchronous timing motor 3| hav ng itsshaft 31A terminating in one justment of knob without rotating motor: 3|.

This timer includes timing switch.contacts.32 which are closed by means of the; time adjustknob 54.

ing knob K in the setting of the timer for the given cooking period but are opened by the motor at the close of the measured period. In set ting the process timer, the knob K is turned to rotate the shaft 3|B which carries the cam 34. As the shaft and the cam are manually rotated, the follower 35 rides on the high part of the cam to close the switch contacts 32. When, however, the motor operates to measure the process interval, the cam 34 rotates until the follower drops into the cam notch 36 at the end of the interval, to open the switch contacts 32.

This system also utilizes a self-restoring auxiliary timer 40 which measures a predetermined time interval, for example five minutes, during which the retort is to be vented. This timer includes a synchronous motor 4| having its shaft 42 terminating in one plate of a clutch 43. The

other plate of the clutch is carried by the reset ting shaft 42A which is rotated by the motor in one sense and is reset in the reverse sense to its normal position, by the spring 45. It will be understood that the plates of the clutch are brought into engagement by the solenoid 44 which is energized simultaneously with the operation of the motor 4|. The resetting shaft 42A carries a cam 4'! which is engaged by a cam follower 49. This follower closes a switch 49, as shown, until the follower drops into the notch in the cam 41 at the conclusion of the timed interval as will be further described. The resetting shaft 42A is provided with arm 50 alined with the notch in cam 41. The rotation of the arm 50 in one direction during restoration, is terminated by a stop 5| which is adjustable'at will to change the duration of the time interval to be measured by the auxiliary timer. While this stop can be adjusted in any convenient manner, it is herein shown as carried by a crank arm 52 on a rotatable shaft 53' which terminates in the adjusting The functioning *of this auxiliary timer will be set forth in the further description of the operation of the system.

The system also utilizes an electric contact thermometer 4 with its bulb projecting into a protective well 4A, although in the diagram, for simplifying the disclosure, the thermometer is shown spaced apart from its well. This thermometer may be of the type disclosed in the Norwood Patent 986,023, granted March 'I, 1911.

The operation and control of the processing cycle in the report will best be understood'by explaining a complete cycle of operation. At'the beginning of a new cycle the retort is filled with cans or jars to be processed and the cover 6 isthen closed on the retort in sealed position, by means of the bolts 1 and the butterfly nuts 8.

At the start of the cycle, the process timer is set for'a given cooking period and the manual stop cook 58 is opened to the position shown. As a result of'setting theprocess timer, the switch contacts 32 are closed. As soon as the timer contacts 32 are closed, circuits to be described, opcrate the motor 4| of the auxiliary timer 40 and energize the solenoid'of valve '18 which is moved to its alternate position 'from that shown, so that compressed air exhausts to the atmosphere from the motor of valve 30, permitting it to open and thereby vent the retort. The operating circuit for the motor 4| extends from one 'side of the power source L1, the switch 32 (now closed), conductor 19, switch 49 (now closed) winding of the motor 4| to theother side of the power source L2. At the same time a circuit is completed for the winding of magnet which causes the clutch'plate 43 to engage a related plate source. When this solenoid is thus energized in this circuit, it moves the plunger of its valve to its upper position wherein compressed air is supplied from the pipe 62. branch pipe 63, through the valve 59, to the mechanism of the temperature controller T. On the operation of valve 59, compressed air is cut off from pipe 65 so that the bleed valves l4 and I! open to vent steam to the atmosphere and compressed air is cut of! from the pressure controller P. Since the temperature within the retort is below the predetermined value, the Bourdon spring 66 with capillary 61 and bulb |2 comprising a well-known tube system, as well as the filling medium therein, respond to the retort temperature. Bourdon spring 66' acts through link 68 to elevate the bafile lever 59 which is pivoted at 19 so that the baflie 12 is spaced from the nozzle II. It will be understood that air supplied through the solenoid valve 59 and the pipe 13 escapes through the orifice l4 and through nozzle 1|, depending on the position of the baffle 12. Under the condition assumed, the back pressure in the nozzle will be relatively low so that the capsular chamber 15 of relay valve 15 will be contracted to open relay valve 16. Compressed air from the pipe 13 is thus applied through the open relay valve 16 and the pipe 11 to the diaphragm motor top of the steam valve I0. The application of compressed air to the'top of this motor, opens this valve to permit steam to be supplied through the steam pipe, 9 to the interior of the retort. This steam continues to be supplied to the retort in this manner until the temperature therein reaches 'a predetermined value for example 240 F. At this time the Bourdon spring 66 operating through the link 68 lowers, the bafile lever 69 and the baifie l2 towardthenozzle 1| until the back pressure at this nozzle is sufficient to expand the capsular chamber-15, to close the relay valve 16. If, during the processing cycle, the temperature in the retort drops below the predetermined value, the Bourdon spring tends to move the baflle away from the nozzle to operate the relay valve again. thereby supplying throttled compressed air through the pipe '11 to the motor of the valve It. This valve thus supplies throttled steam to the retort tomaintain the given temperature therein.

In accordance with the present invention, the retort 5 is vented to the pipe 29 through valve 3|), to expel all air therefrom, under the joint control of the electric contact thermometer 4 which closes a break point in an electric control circuit, when a given temperature, for example 220 prevails in'the retort, and under control ofthea'u'xiliary timer 4|! which-measures apredetermined interval of time and opens its contacts 49 at the end of this period. Until both of these conditions have been satisfied, the solenoid valve.'|8jwill be held in its energized position wherein the motor top of valve 30 exhausts to 18 is released to its closed position wherein compressed "air is applied'to the diaphragm motor of valve 30'to close it. It should be pointed out aooaeee that theMwinding of the solenoid valve is maintained energizedby either of two-circuitsn One of. these circuitsis traceable from leadLr of the power source, contacts .32.:of the timer .tnow closed), conductorJQ, switch contactsASof the auxiliary timer, conductor 80, winding of. solenoid valve .'|-8,to.the other, lead L2 of the commercial power source. The other energizing circuit of the solenoid valve, istraceable' from the lead L1 of the power source, switch contacts 32 of .the process timer, conductors 19 and 82, contacts of relay 83 (now closed), conductor 8ll, winding of valve 18, tothe other lead L2 of the power source. When, however, the temperature in the retort reaches a predetermined value, for example, 220 theelectr'ic contact thermometer 4, which is protected by. the resistor 84,-.closes its contacts. Onfithe closure of these contacts, the relay 83 vv is energized-in an obvious circuit,. and at its contacts, breaks, one of the energizing circuits of the solenoid valve 18. However the other energizing circuit of this valve is maintained for a predetermined time interval, for example five minutes, by the auxiliary timer. At the conclusion of this interval, the auxiliary timer opens its contacts 49, to open the other energizing circuit and to stop the motor 4|. In this manner the solenoid valve 18 will control the venting of the retort for the given interval and until the given temperature is reached in the retort.

While these operations have been taking place, steam has been supplied to heat up the retort and its contents under the control of the temperature controller T. When the predetermined process temperature, for example 240 F., is reached, the back pressure in the nozzle II will expand the capsular diaphragm 15 of the relay valve 16, to close this valve. When relay valve 16 closes it cuts oil compressed air from the motor of the valve to which cuts ofi the steam. It will be understood that if the temperature in the retort tends to drop during the cooking cycle, the temperature controller T will operate the valve Ill, to throttle the steam supplied to the retort so that a given uniform temperature will be maintained. When the back pressure in the nozzle H operates the relay valve 16 at the time that the process temperature is reached, this pressur causes the chamber 86 to expand and thereby close its switch contacts 81. On the closure of the contacts 87, the relay 88 is energized from one side L1 of the power line, through contacts 32 of the primary timer, conductor 19, winding of relay 88, through the contacts 81, to the other side L2, of the power line. Under the control of thiscircuit the relay 88 is energized and closes a locking circuit for itself through its winding, through conductor 90, and through its armature 89 and contacts to the other side L2 of the power line. In this manner, the relay 88 is locked in, even if contacts 81 should open when the back pressure at the nozzle H temporarily drops. The operation of this relay thus maintains an operating circuit for the process timing motor 3! until this motor opens the timer switch contacts 32 at the conclusion of the cooking cycle.

At the end of the cooking portion of the cycle when the timer switch contacts 32 are opened. the energizing circuit of the winding 60 of the solenoid valve will be interrupted so that this valve assumes the position illustrated. With the valve in this position compressed air will be cut off from the temperature controller T so that the steam valve It! cuts air the supply of steam With compressed air in this pipe and inthe branch pipesconnected thereto the vent valves 14 and flare closed and the pilotvalve 92 is movedto. the positionshown, wherein the'upper motor.-. chamber of: valve. 22 iisvented-to the at? mosphere. Compressed air from pipe 65, is also suppliedto; the pressure controller P which main-. tains. a predetermined-pressur in the retort during thecooling period. Duringthe cooling period the.operator.;gradually admits. cooling water to the retort through stop cock. [9. NVhile the cooling. water is being admitted,.the..pressure controller .P, throttles the air. pressure. supplied to the lower motor chamber of valve 22 and to the overflow valve .24, thereby maintaining the desiredpressure in the'retort. q y I -Al11the end of the cooling portion of the cycle, theoperator closes the hand valve. l9 to stop the flow of cooling water to the retort. Also the operator closes the stop cook 58. This results in opening of the bleed valves M and I! as well as the opening of the vent and drain valve 30..

The cover 6 can then be opened and the processed cans removed ready for recharging the retort for the unprocessed cans after which the described cycle is repeated.

What I claim is:

1. In a food processing system, a retort arranged to be sealed during a process cycle, said retort having a vent therein, a steam pipe communicating with said retort for heating the contents thereof, a temperature controller governing the steam admitted through said pipe to said retort for maintaining a predetermined cooking temperature therein, a settable process timer for measuring and controlling the duration of a given cooking cycle in the retort, means responsive to the cooking temperature value being attained in the retort for starting said process timer, a lapsed time interval measuring mechanism th operation of which is initiated responsive to the setting of said process timer and including a device operated at the conclusion of said interval, a temperature actuated device operated in response to a given temperature in said retort but below the cooking temperature, and means jointly controlled by both of said devices for maintaining said vent openfor the given interval and until said given temperature is reached 7 in the retort, and then closing the same.

2. In a food processing system, a retort arranged to be sealed during a process cycle, said retort having a vent therein, a, steam pipe communicating with said retort for heating the contents thereof, a temperature controller governing the steam admitted through said pipe to said retort for maintaining a predetermined cooking temperature therein, a settable process timer for measuring and controlling the duration of a given cooking cycle in the retort, means responsive to the given cooking temperature value being attained in the retort for starting said process timer, a lapsed'time interval measuring mechanism including a device operated at the conclusion of said interval, means including said process timer for initiating the operation of said mechanism, a temperature device having a portion subjected to the temperature within the retort and operated in response to a given temperature therein but below the cooking temperature; and means jointly controlled by both of said devices for maintaining said vent open for the given interval and until said given temper'ature is reached in the'retort, and then closingthesame.

3.: In a food processing system, a retort arranged to vbe sealed during. a process cycle, said retort h'aving'a ventltherein, mechanism controlling the opening of'said vent, a steam pipe communicating with said retort for heating the contents thereof, a temperature controller governing the steam admitted through said pipe to said retort for maintainingf-a. predetermined cooking. temperature therein, a primary timer settable for measuring. and controlling the. durationcof a given cooking cycle in the retort, means responsive to the given cooking temperature value bei'ngattained in. the retort for starting said timer, a lapsed time interval measuring mechanism started into operation in response tothe setting of said primary timer and including a closedswitch operated to open at the conclusion of said interval, an electric contact thermometer 8 operated in response to a given temperature in said retort lower than said cooking'temperature, andelectrical means jointly actuated in response to the operation of both of said thermometer and saidlswitch for operating said mechanism to close said vent. I Tv CARLW.SANDERS.

, REFERENCES CITED The following references are of record in the file of this patent:-

UNITED STATES PATENTS

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