HK1141421B - Automatic top-off for deep fat fryers - Google Patents

Description

Automatic filling device for deep fryer

This application claims the benefit of U.S. provisional patent application serial No.60/918,843, filed on 3/19/2007, which is incorporated herein by reference.

Background

1. Field of the invention

The present invention relates to fryers for the food service industry. More particularly, the present invention relates to fryers for the food service industry that are capable of filling and maintaining a volume of cooking oil in a cooking vessel. Still more particularly, the present invention relates to fryers for the food service industry that are capable of filling and maintaining an amount of cooking oil in a cooking vessel based on a sensed oil temperature.

2. Description of the related Art

Fryers are essential in the food service industry, particularly for the fast food service industry. In order to cook food quickly, the cooking oil should be filled in the cooking fryer and maintained at a specific temperature at any time. A large amount of oil is absorbed by the food product during the cooking process, resulting in a loss of oil volume. In addition, the rate of temperature increase directly leads to a reduction in the life of the oil. Therefore, it is desirable to maintain the oil volume at an optimal level during cooking to minimize oil degradation caused by the heating process. It is therefore necessary to keep the fryer full of oil at any time during the cooking process. The absence of an automatic system for maintaining the oil at an optimal level and temperature while cooking ignores the amount of oil and reduces the effective life of the cooking oil.

Accordingly, there is a need for a fryer that fills and maintains a desired amount of cooking oil and temperature for a commercial fryer without operator intervention.

Disclosure of Invention

The present disclosure provides a deep fryer that fills a fryer pot and maintains an amount of cooking oil in the fryer pot in response to a temperature sensor in a particular fryer pot.

The present disclosure also provides for a deep fryer that fills and maintains the volume of oil in one or more of a plurality of fryer pots in response to temperature sensors in one or more particular fryer pots.

The present disclosure also provides for a deep fryer that fills one or more fryer pots and maintains an amount of cooking oil in one or more of the fryer pots only when a temperature sensor in the one or more fryer pots detects a predetermined high temperature of cooking oil.

The present disclosure further provides for a deep fryer that activates a pump and solenoid valve associated with a particular fryer pot to fry and maintain an amount of cooking oil in the fryer pot in the deep fryer pot only when a temperature sensor associated with the fryer pot detects a predetermined high temperature of cooking oil.

The present disclosure further provides for a deep fryer that activates a pump and a solenoid valve associated with one or more of the plurality of fryer pots to fill and maintain the volume of cooking oil only when a temperature sensor associated with the one or more fryer pots detects that the cooking oil has reached a predetermined temperature.

The present disclosure still further provides for a deep fryer that fills and maintains the volume of cooking oil in one or more fryer pots when the oil level in the fryer pot has dropped, upon detection of a predetermined low temperature, wherein a temperature sensor activates a pump and a solenoid valve in a particular fryer pot is opened to begin filling.

The present invention provides a deep fryer that stops filling in the fryer pot when a predetermined oil temperature is detected.

The present invention provides a deep fryer with a heating element disposed within a fryer pot having a temperature sensor coupled thereto that senses oil temperature, which senses oil temperature to activate another sensor that senses oil temperature in response to oil level in the fryer pot to initiate or terminate filling of the fryer pot.

The present invention further provides a deep fryer for introducing new oil to one or more of a plurality of fryer pots in response to a low level of liquid in a particular fryer, the oil being introduced above an oil line by means of a separate conduit, thereby minimizing contamination of the new oil by used oil.

The present invention also provides a fryer having two pumps; one of the two pumps is used to pump fresh cooking oil over the oil line and the other of the two pumps is used to filter used cooking oil.

The present disclosure further provides a deep fryer having two independent oil supply lines for independently pumping new and used oil to the fryer pots such that the new and used oil do not contact each other until pumped into a particular fryer pot.

The present invention provides a fryer with a fillable reservoir that is secured to the fryer housing.

The present invention provides a fryer with a loop control of a temperature activated switch and mechanical contacts that fills and maintains the volume of cooking oil in a fryer pot in the fryer.

Accordingly, there is a need for a deep fryer having multiple fryer pots that can be individually filled in response to a submerged oil level sensor located in each fryer pot; a submerged temperature sensor in each fryer pot is used by a temperature sensor in each fryer pot.

These and other benefits and advantages are provided by a system for automatically filling and maintaining fryer pots with oil in a fryer having a fryer and a plurality of fryer pots disposed within the fryer. Each of the plurality of fryer pots comprising a first temperature sensor, a second temperature sensor, and a valve that is energized in response to a temperature sensed by the first temperature sensor and closed in response to a temperature sensed by the second temperature sensor, wherein when the first temperature sensor senses a first predetermined temperature, the second temperature sensor is activated to initiate a fill cycle of the fryer pot in response to the first temperature sensor and open the valve of the fryer pot.

A system for automatically filling and maintaining fryer pots with oil in a fryer. The fryer has a plurality of fryer pots and each of the plurality of fryer pots includes a first thermal switch and a second thermal switch. The system further provides a pump and a plurality of valves associated with one of the plurality of fryer pots. A second thermal switch in one of the plurality of fryer pots is activated by the first thermal switch in one of the plurality of fryer pots in response to the first predetermined temperature to initiate a filling cycle of the fryer pot. The second thermal switch opens one of the pump and the plurality of valves in response to a second predetermined temperature.

A system for automatically filling and maintaining fryer pots with oil in a fryer, the system having a fryer; a plurality of frying pans. Each of the plurality of fryer pots having a first thermal switch, a second thermal switch, a pump and a plurality of valves. A second thermal switch in one of the plurality of fryer pots is activated by the first thermal switch in one of the plurality of fryer pots in response to the first predetermined temperature to initiate a filling cycle of the fryer pot. A second thermal switch opens the pump and one of the plurality of valves to provide oil to the fryer pot in response to a second predetermined temperature and closes the pump and one of the plurality of valves in response to a third predetermined temperature.

Brief description of the drawings

Other and further benefits, advantages and features of the present invention will become apparent by reference to the following description when taken in conjunction with the accompanying drawings wherein like reference characters denote like elements of structure:

FIG. 1 shows a front view of a deep fryer having three fryer pots and an internal stationary reservoir in accordance with the present invention;

FIG. 2 shows a rear view of a frying pan with a temperature sensor according to the invention;

FIG. 3 shows a front perspective view of a frying pan with a heating element and a temperature sensor according to the present invention;

FIG. 4 shows a side view of a frying pan having a temperature sensor, a linear motion motor, and a drain valve and a fill valve in accordance with the present invention;

FIG. 5 shows a pump according to the present invention and three solenoid valves, each of which can be actuated individually to fill a respective fryer pot; and

figure 6 shows a side view of a fryer housing according to the present invention.

Detailed Description

Referring to FIG. 1, a front perspective view of a fryer is shown and generally designated by reference numeral 10. Fryer 10 has a housing 15 and three fryer pots 20, 25 and 30. Fryer pots 20, 25 and 30 each contain oil for frying food, which is commonly used in the commercial food industry. Fryer pots 20, 25 and 30 each have a dedicated control panel 35, 40 and 45, control panels 35, 40 and 45 respectively controlling the cooking of the particular fryer pot. Housing 15 also has an individually controllable fill tube 50 associated with each particular fryer pot 20, 25 and 30. The housing 15 also has a power button 55 at its front with an oil reservoir 60 and an indicator light 65 operatively associated with the oil reservoir 60. The housing 15 also has a separate door 70 which when opened provides access to the oil reservoir 60. More doors 70 may also be opened and used for periodic maintenance as needed on a commercial cooking system. The housing 15 also has indicator lights 75, which lights 75 are energized by the control panels 35, 40, and 45 at predetermined times to indicate that filtration is required. Although the housing 15 is shown with three fryer pots, the housing may include any number of fryer pots depending on the needs of the food service person.

Referring to fig. 2 and 3, a single frying pan 20 is shown. Frying pans 25 and 30 in fig. 1 each have the same elements and functions as frying pan 20. Fryer pot 20 has a cooking area 100 and a submersible fuel level sensor 105. Frying pan 20 also has a submersible safety sensor 110 and an internal heating element 115. The heating element 115 has a temperature sensor 120 associated therewith.

Referring to fig. 1, 4 and 5, fryer pot 20 has a drain valve 155 driven by one of the pair of linear motion motors 130, which drains used oil from fryer pot 20. Fryer pot 20 also has a pipe system 125, said pipe system 125 feeding used oil into fryer pot 20 through an oil return valve 140 driven by the other of the pair of linear drive motors 130. Single fryer pot 20 has a remotely located solenoid valve 135 and a pump 160 associated with solenoid valve 135 that operates and supplies fresh oil to fryer pot 20 through a conduit 165 that terminates at fill tube 50. Conduit 165 is separate from tube 125 which supplies used oil to fryer pot 20. The solenoid valve 135 is opened and closed in response to the temperature sensor 105. Pump 160 is also operatively associated with temperature sensor 105 to operate in response to a predetermined temperature.

As shown in fig. 5, there are three solenoid valves 135, 145 and 150. Solenoid valves 145 and 150 are operatively connected to filling fryers 25 and 30, respectively, in response to respective submersible temperature sensors disposed in filling fryers 25 and 30. Pump 160 serves three solenoid valves 135, 145 and 150 depending on the level of cooking oil in each fryer pot.

The following description pertains to the operation of frying pan 20. In operation, fresh oil pump 160 may only be operated by submersible temperature sensor 105 to begin automatically filling fryer pot 20 once temperature sensor 120, which is located proximate to heating element 115, detects that a first predetermined temperature has been reached. The first predetermined temperature ranges from about 250 ° F to 280 ° F. For example, if sensor 120 senses an oil temperature of approximately 260 ° F, submersible temperature sensor 105 can operate to energize solenoid valve 135 and new oil pump 160. Submersible temperature sensor 105 will energize solenoid valve 135 and new oil pump 160 only at a predetermined temperature as described below. Monitoring sensor 120 is intended to prevent premature operation of pump 160 and improper filling of fryer pot 20 and possibly over-filling of the intended volume. In addition, the volume of cold oil is much smaller than the volume of hot oil. The sensor 120 may also prevent the pump 160 from operating prematurely during startup when the amount of oil is small due to low temperature. Additionally, when sensor 120 detects a temperature that is about 5-25F below the first predetermined temperature, sensor 105 will not operate to energize pump 160, thereby preventing the system from being loaded if it has been discharged or otherwise not in use.

The submersible temperature sensor 105, switch, may operate once the sensor 120 senses a second predetermined temperature in the range of approximately 260 ° F to 290 ° F. When temperature sensor 105 senses a temperature within this second temperature range, it will close and activate pump 160 and solenoid valve 135. A temperature in this range indicates that sensor 105 is no longer immersed in oil and must begin filling in order for fryer pot 20 to again have the proper amount of oil. While new cooking oil is being poured into fryer pot 20, it also needs to be heated by heating element 115. Once submersible temperature sensor 105 senses a third predetermined temperature in the range of approximately 300F to 330F, it will turn on and thus stop filling fryer pot 20. A temperature in this third range indicates that sensor 105 is again immersed in oil and that frying pan 20 has the desired amount of oil. Submersible thermal sensor 105 is wired to solenoid valve 135 to ensure that the appropriate fryer pot 20 will be filled and is not one of the other fryer pots 25 or 30 in housing 15.

If sensor 105 fails to stop pump 160, sensor 110, a second submersible thermal sensor located at a higher position in fryer pot 20, is activated. Sensor 110 is electrically wired in series with pump 160 to stop the filling operation. This second thermal sensor 110 functions as a safety feature to prevent overflow of fryer pot 20 in the event that sensor 105 does not stop pump operation. Additionally, an additional safety feature is an off delay timer associated with the pump 160 to stop operation of the pump and prevent spillage. The sensor 110 maintains pump life even if the oil level in the reservoir is low or the reservoir oil is not replaced by the user.

Although the filling system has been described as having an immersed temperature sensor 120 associated with heating element 115, the temperature sensor may also be located on the side of the fryer pot in order to also sense the temperature of the surface of the fryer pot.

When new oil is fed into fryer pot 20, it enters above the oil line through a separate conduit 165 that terminates at fill tube 50, thereby preventing the new oil from contacting the used oil and becoming contaminated before it enters fryer pot 20. With a higher entry point, the possibility of disturbing the debris at the bottom of fryer pot 20 is eliminated. Additionally, the higher entry point reduces the likelihood that solenoid valves 135, 145, and 150 will become blocked.

Referring to fig. 1 and 6, the housing 15 and reservoir 60 are shown. The oil used to fill frying pans 20, 25 and 30 is located in reservoir 60. To alert the user that the oil in the reservoir 60 is at a low level, the spring on which the reservoir rests stretches to lift the reservoir and activate an alarm or light. Alternatively, the alarm or light may be initiated by an off delay timer operatively associated with pump 160 that detects that a predetermined expected interval for refilling the fryer pot has been exceeded, thereby indicating that the reservoir is empty. The single reservoir is then removed and a new filled reservoir is inserted. Alternatively, a single permanent reservoir is arranged below all fryer pots 20, 25 and 30, and the permanent reservoir is filled.

Having thus described the invention with particular reference to the preferred forms thereof, it will be obvious that various changes and modifications may be made therein without departing from the spirit and scope of the invention as defined in the present disclosure.

Claims (11)

1. A system for automatically filling and maintaining fryer pots with oil in a fryer, said system comprising:

a fryer; and

a plurality of fryer pots disposed within the fryer pot, each of the plurality of fryer pots comprising a first temperature sensor, a second temperature sensor, and a valve that is energized in response to a temperature sensed by the first temperature sensor and closed in response to a temperature sensed by the second temperature sensor,

wherein when the first temperature sensor senses a first predetermined temperature, the second temperature sensor is activated to initiate a fill cycle of a fryer pot and open the valve of the fryer pot in response to the first temperature sensor.

2. The system of claim 1, further comprising a pump and a plurality of valves operatively associated with said valves, wherein said pump and said valves are actuated when said second temperature sensor senses a second predetermined temperature, and each of said plurality of valves is operatively associated with one of said plurality of fryer pots.

3. The system of claim 2, further comprising a third temperature sensor located in each of said plurality of fryer pots and operatively associated with said second sensor, wherein said pump and said valve are not operated when said second temperature sensor senses a third predetermined temperature having a value greater than said second predetermined temperature, and wherein said third temperature sensor deactivates said second temperature sensor when said second temperature sensor does not detect said third predetermined temperature.

4. The system of claim 2, wherein said second temperature sensor does not initiate a fill cycle to begin the fryer pot when said first temperature sensor does not sense a first predetermined temperature.

5. The system of claim 1, wherein the first temperature sensor is located near a heating element disposed at a bottom surface of the fryer pot, and wherein the second temperature sensor is located at a greater distance from the bottom surface of the fryer pot than the first temperature sensor.

6. The system of claim 1, wherein the first predetermined temperature ranges from 250 to 280 ° F.

7. The system of claim 2, wherein the second predetermined temperature ranges from 260 to 290 ° F.

8. The system of claim 3, wherein the third predetermined temperature ranges from 300 to 330 ° F.

9. The system of claim 1, wherein the first temperature sensor fails to activate the second temperature sensor when the first temperature sensor senses a temperature in a range of 5 ° F-25 ° F below a first predetermined temperature.

10. The system of claim 3, wherein the first temperature sensor, the second temperature sensor, and the third temperature sensor are mechanical thermal switches that turn on and off in response to a predetermined temperature.

11. The system of claim 2, wherein said plurality of valves associated with each of said plurality of fryer pots is a solenoid valve.