Fryer

Abstract

To provide a fryer capable of removing fry residues accumulated in an oil tank while continuing a large amount of frying without interruption, and capable of improving operation efficiency.SOLUTION: A fryer (1) for heating frying oil in an oil tank (2) by a heater (8) to fry a food material put in the oil tank, comprising: an upper oil tank in which the heater is disposed and in which frying of the food material is performed; a lower oil tank provided continuously with a lower part of the upper oil tank and having a discharge port (50) for discharging frying residues generated in the oil tank together with the frying oil at a deepest part and a plurality of inclined bottom plates (20) inclined toward the discharge port; When a frying residue discharge button is operated, a prescribed amount of frying oil is added to the lower oil tank while continuing frying cooking in the upper oil tank, and the discharge valve 6 is opened to discharge the same amount of frying oil from the lower oil tank.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a fryer used for cooking fried foods, and more particularly to a fryer having a heater for heating frying oil provided in the middle of the depth direction of an oil tank. [Background technology]

[0002] Conventionally, this type of fryer has been known to have a heater located midway in the depth direction of an oil tank that stores frying oil, with the upper oil tank above the heater serving as a high-temperature section in which fried foods are cooked, and the lower oil tank below the heater serving as a low-temperature section in which moisture and fried food debris produced in the oil during frying sink to the lower oil tank.

[0003] Known specific methods for keeping the lower oil tank at a low temperature include air-cooling the lower oil tank by natural heat dissipation without providing any active cooling means (Patent Document 1), and forcibly cooling the lower oil tank by providing a water tank that completely covers the lower oil tank from the outside (Patent Document 2). If these methods are used to suppress the oil noise in the lower oil tank to about 80 degrees Celsius, evaporation of water that has settled in the lower oil tank is prevented, suppressing deterioration due to oxidation of frying oil and oil splashing in the upper oil tank, and also making it possible to promote the settling of fried food debris in the lower oil tank.

[0004] Furthermore, when using commercial fryers in stores and the like, it is necessary to periodically replace the large amount of frying oil stored in the oil tank, as well as to remove any fried debris that has accumulated in the oil tank and clean the oil tank. For this reason, a drain port leading to an external tank is provided at the deepest part of the lower oil tank, and the frying oil in the oil tank can be discharged into the external tank together with the fried debris. In addition, the bottom plate of the lower oil tank is an inclined bottom plate that is inclined toward the drain port, so that fried debris that has settled in the lower oil tank during frying accumulates on the inclined bottom plate, and when the frying oil is discharged into the external tank, the fried debris flows into the drain port along with the frying oil (Patent Document 1 and Patent Document 2). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2016-073487 [Patent Document 2] Patent No. 5901624 Summary of the Invention [Problem to be solved by the invention]

[0006] For example, when a large amount of deep-fried food is cooked continuously for a long period of time in a commercial fryer, a large amount of deep-fried food debris accumulates at the bottom of the lower oil tank, and if cooking is continued in this state, the volume of the lower oil tank will decrease, causing problems such as the deep-fried food debris floating in the upper oil tank and the deterioration of the frying oil. For this reason, it would be convenient to be able to remove the deep-fried food debris from the oil tank even during continuous cooking.

[0007] However, in conventional fryers, deep-frying is first completed, the temperature of the frying oil is lowered to a certain extent, and then the oil is discharged into an external tank, at which time the deep-frying residue is removed from the oil vat. The fryer in Patent Document 1 also has a filtration circulation mode in which the oil is filtered while circulating between the oil vat and the external tank. However, this filtration circulation mode is separate from the fryer mode in which deep-frying is performed, and deep-frying residue in the oil vat could not be removed without interrupting deep-frying. In other words, conventional fryers cannot remove deep-frying residue while continuing deep-frying, which poses a problem for commercial fryers that perform large-volume deep-frying. [Means for solving the problem]

[0008] The present invention has been made in consideration of such problems, and its purpose is to provide a fryer that can remove fried food residue accumulated in an oil tank while continuing to fry large quantities of food without interruption, thereby increasing operating efficiency.

[0009] That is, the present invention is a fryer that uses a heater to heat frying oil stored in an oil tank and deep-fry food ingredients placed in the oil tank, and includes an upper oil tank in which the heater is disposed and in which the food ingredients are deep-fried; a lower oil tank that is disposed below the upper oil tank and is continuous with the upper oil tank, has a discharge port at its deepest part for discharging fried food particles generated in the oil tank together with the frying oil, and has a plurality of inclined bottom plates that slope toward the discharge port; and a cooling water tank that is disposed around the lower oil tank and is filled with cooling water to forcibly cool the frying oil in the lower oil tank. a water-cooled jacket for cooling the oil, a discharge valve for opening and closing a discharge flow path connected to the discharge port, a reserve tank for removing fried debris from the frying oil discharged through the discharge valve and storing the fried oil after the debris has been removed, a return flow path having an oil injection pump for injecting the frying oil in the reserve tank into the lower oil tank, a control unit for managing the operation of the heater, the opening and closing of the discharge valve and the operation of the oil injection pump, and a fried debris discharge button for instructing the control unit to discharge fried debris that has settled in the lower oil tank during frying cooking. When the fried debris discharge button is operated, the control unit drives the oil injection pump to add a predetermined amount of frying oil from the reserve tank to the oil tank and opens the discharge valve to discharge the same amount of frying oil from the lower oil tank. [Effects of the Invention]

[0010] According to the present invention, when the debris discharge button is operated during deep-frying in the upper oil vat, a predetermined amount of frying oil is discharged from the lower oil vat along with the debris, and new oil of approximately the same amount as the discharged amount is poured from the reserve tank into the lower oil vat. At this time, the new frying oil poured from the reserve tank is poured into the lower oil vat, not the upper oil vat, so the oil temperature in the upper oil vat does not drop suddenly during deep-frying. Therefore, it is possible to continue deep-frying a large amount of food without interruption while removing the debris accumulated in the oil vat, thereby improving the operating efficiency of the fryer. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a schematic cross-sectional view showing an example of an embodiment of a fryer to which the present invention is applied. [Figure 2] FIG. 2 is a block diagram showing a control system of the fryer according to the embodiment. [Figure 3] FIG. 2 is a schematic cross-sectional view showing the flow of frying oil near the inclined bottom plate in the fryer of the embodiment. [Figure 4] FIG. 2 is a plan view showing the bottom of the oil tank. DETAILED DESCRIPTION OF THE INVENTION

[0012] The flyer of the present invention will be described in detail below with reference to the accompanying drawings.

[0013] Figure 1 shows an example of a commercial fryer to which the present invention is applied. This fryer 1 is a freestanding type used in the kitchen of a restaurant or other establishment, and is capable of frying food by putting about 18 liters of frying oil 10 into the oil tank.

[0014] This fryer 1 comprises an oil tank 2 for storing frying oil, a housing 3 for supporting the oil tank 2, a reserve tank 4 housed within the housing 3 below the oil tank 2, and a discharge flow path 5 for discharging the frying oil from the oil tank 2 to the reserve tank 4. A discharge valve 6 is provided in the discharge flow path 5, and when the discharge valve 6 is opened, the frying oil in the oil tank 2 flows into the reserve tank 4 under its own weight. A mesh filter 7 is provided midway along the discharge flow path 5, and large fried food particles are collected by the filter 7 as the frying oil flows into the reserve tank 4.

[0015] The oil tank 2 is composed of an upper oil tank 2a where deep-frying takes place and a lower oil tank 2b located below and continuous with the upper oil tank 2a. A heater 8 for heating the frying oil is provided in the upper oil tank 2a, and by energizing the heater 8, the frying oil in the upper oil tank 2a can be heated to any temperature. Meanwhile, the lower oil tank 2b has a discharge port at its deepest part, which is connected to the discharge flow path 5. A plurality of inclined bottom plates 20 are arranged around the discharge port, inclined toward the discharge port, and these inclined bottom plates 20 are connected together to form the bottom plate of the oil tank 2. In the illustrated example, four inclined bottom plates 20 are arranged around the discharge port, so that the bottom plate of the oil tank 2 has an inverted pyramid shape.

[0016] The upper oil tank 2a is surrounded by a heat insulating material 21, while the lower oil tank 2b is surrounded by a water-cooled jacket 22 filled with cooling water. Therefore, when the heater 8 is energized, the frying oil 10 in the upper oil tank 2a, which is provided with the heater 8 and covered by the heat insulating material 21, is heated to a high temperature (e.g., 180°C), while the frying oil 10 in the lower oil tank 2b is forcibly cooled by the water-cooled jacket 22, so that the temperature of the frying oil 10 in the lower oil tank 2b is maintained at a low temperature below 100°C (e.g., 80°C). Although not shown, a cooling water supply pipe and a discharge pipe are connected to the water-cooled jacket 22, so that the cooling water heated by cooling the lower oil tank 2b can be discharged to the outside and new low-temperature cooling water can be supplied.

[0017] Deep-frying of ingredients is performed in the upper oil tank 2a, where the frying oil is heated by the heater 8. Meanwhile, moisture and fried debris released from the ingredients into the frying oil during deep-frying sinks from the upper oil tank 2a to the lower oil tank 2b. As described above, the frying oil in the lower oil tank 2b is kept at a low temperature of less than 100°C, so moisture that reaches the lower oil tank 2b sinks to the vicinity of the inclined bottom plate 20 without evaporating. Furthermore, because the temperature of the frying oil 10 in the lower oil tank 2b is significantly lower than that in the upper oil tank 2a, there is no convection of the frying oil from the lower oil tank 2b to the upper oil tank 2a, and the fried debris that has settled in the lower oil tank 2b accumulates on the multiple inclined bottom plates 20 without rising to the upper oil tank 2a.

[0018] Although the frying oil 10 flowing from the oil tank 2 through the total discharge flow path 5 into the reserve tank 4 passes through the filter 7, fine fried debris and moisture are not captured by the filter 7 and are contained in the frying oil 10. In other words, the filter 7 captures only relatively large fried debris. Therefore, the frying oil 10 that passes through the filter 7 contains fine fried debris and moisture, which settle to the bottom of the reserve tank 4 when the frying oil 10 is stored in the reserve tank 4 for several hours. For example, if the frying oil 10 is drained from the oil tank 2 to the reserve tank 4 after the end of the day's work and is left in the reserve tank 4 until the next morning, the fine fried debris and moisture will have settled to the bottom of the reserve tank 4 by the time work begins the next day.

[0019] Meanwhile, a return flow path 40 is provided between the reserve tank 4 and the oil tank 2, and by driving an oil supply pump 41, the frying oil 10 present in the reserve tank 4 can be appropriately supplied to the oil tank 2. The return flow path 40 is not connected to the bottom of the reserve tank 4, and even when the oil supply pump 41 is driven, fine fried food residue and moisture that have settled at the bottom are not sucked up into the return flow path 40 but are retained in the reserve tank 4. The return flow path 40 is connected to the oil tank 2 below the heater 8, and more specifically, is connected to the boundary between the upper oil tank 2a and the lower oil tank 2b above the upper end of the inclined bottom plate 20 of the lower oil tank 2b.

[0020] FIG. 2 is a block diagram showing the control system of the fryer 1. The fryer 1 includes a power supply unit 11 that receives power from an AC power source, and a control unit 12 with a built-in microprocessor receives power from the power supply unit 11 and controls the operation of the oil supply pump 41, the heater 8, and the discharge valve 6. The control unit 12 is also connected to a temperature sensor 13 that measures the temperature of the frying oil 10 in the upper oil tank 2a. The control unit 12 references the output signal of the temperature sensor 13 at predetermined time intervals and commands the power supply unit 11 to supply power to the heater 8 according to a pre-stored program so that the frying oil 10 in the upper oil tank 2a is maintained at a predetermined temperature (e.g., 180°C). The control unit 12 is connected to an operation panel 14 that serves as a user interface, and the operation panel 14 includes a cooking temperature setting button 15 and a display 16 that displays the current temperature of the frying oil 10 in the upper oil tank 2a.

[0021] The operation panel 14 is provided with a fried residue discharge button 17 for discharging fried residue accumulated in the lower oil tank 2b out of the oil tank 2 during cooking. When a user operates the button 17, the control unit 12 opens the discharge valve 6 for a predetermined period of time, and a predetermined amount (for example, about 4 liters) of frying oil 10 in the lower oil tank 2b is discharged toward the reserve tank 4. In addition, the control unit 12 also starts the oil supply pump 41, and the frying oil 10 in the reserve tank 4 is supplied to the oil tank 2.

[0022] When the fried residue discharge button 17 is operated by the user, the oil supply pump 41 supplies approximately the same amount of frying oil 10 as the amount of frying oil 10 discharged from the lower oil tank 2b to the oil tank 2. The control unit 12 controls the opening time of the discharge valve 6 and the operating time of the oil supply pump 41, so as to ultimately maintain the oil level in the oil tank 2 at an approximately constant position.

[0023] By operating the debris discharge button 17 in this manner, a predetermined amount of frying oil 10 is discharged from the discharge port 50 located at the deepest part of the lower oil tank 2b, and the debris accumulated on the inclined bottom plate 20 located surrounding the discharge port 50 flows into the discharge port 50 together with the frying oil. This makes it possible to discharge debris from the oil tank 2 even during deep frying. Furthermore, since the frying oil 10 discharged from the oil tank 2 by operating the debris discharge button 17 is the low-temperature frying oil (less than 100°C) in the lower oil tank 2b, the temperature of the debris contained therein is also similarly low, and therefore there is no risk of the debris collecting in the filter 7 catching fire.

[0024] Because the temperature of the frying oil 10 dispensed from the reserve tank 4 into the oil tank 2 is close to room temperature, when the oil dispenser pump 41 dispenses the frying oil 10 from the reserve tank 4 into the upper oil tank 2a in response to the operation of the fried debris discharge button 17, the temperature of the frying oil 10 in the upper oil tank 2a drops, necessitating the interruption of frying cooking until the temperature recovers. In this regard, in the fryer of this embodiment, the return flow path 40, which pours the frying oil from the reserve tank 4 into the oil tank 2, is connected to the boundary between the upper oil tank 2a and the lower oil tank 2b. Therefore, even if approximately the same amount of frying oil 10 as that discharged from the lower oil tank 2b is dispensed into the oil tank 2 from the return flow path 40, there is almost no replacement of the frying oil 10 in the upper oil tank 2a. This allows frying cooking to continue in the upper oil tank 2a while the fried debris is being discharged from the lower oil tank 2b.

[0025] When the fried residue discharge button 17 is operated, the discharge of frying oil 10 from the lower oil tank 2b and the supply of oil from the reserve tank 4 to the oil tank 2 by the oil supply pump 41 do not have to occur simultaneously. For example, the supply of oil from the reserve tank 4 to the oil tank 2 may start after the opening of the discharge valve 6, or conversely, the opening of the discharge valve 6 may be delayed after the supply of oil from the reserve tank 4 to the oil tank. The key is that after the control unit 12 has completed the series of operations for discharging fried residue, the amount of oil in the oil tank 2 should be approximately the same as that before the fried residue was discharged.

[0026] On the other hand, if the discharge valve 6 is opened before oil is poured from the reserve tank 4 into the oil tank 2, the amount of frying oil in the oil tank 2 will temporarily decrease, which may cause a decrease in the amount of oil in the upper oil tank 2a where deep-frying is being performed, which may hinder deep-frying. For this reason, when the deep-fry residue removal button 17 is operated, it is preferable to drive the oil injection pump 41 before opening the discharge valve 6, increase the amount of oil in the upper oil tank 2a, and then open the discharge valve 6.

[0027] Furthermore, from the viewpoint of facilitating the discharge of fried food debris accumulated on the inclined bottom plate 20 out of the oil tank 2, it is preferable to discharge the frying oil from the lower oil tank 2b by opening the discharge valve 6 at the same time as the oil supply pump 41 supplies the frying oil in the reserve tank 4 to the lower oil tank 2b. When the oil supply pump 41 discharges the frying oil into the lower oil tank 2b, a flow occurs in the frying oil in the lower oil tank 2b, which makes it easier for the fried food debris on the inclined bottom plate 20 to fly up in the lower oil tank 2b, making it easier to discharge the fried food debris together with the frying oil 10 from the discharge port 50 out of the oil tank 2.

[0028] Furthermore, to facilitate the discharge of fried debris, as shown in FIG. 3, it is preferable to provide a nozzle 42 at the end of the return flow path 40 on the oil vat 2 side, which guides the frying oil dispensed from the reserve tank 4 into the oil vat 2 along the inclined bottom plate 20 of the lower oil vat 2b. When such a nozzle 42 is used, when the oil supply pump 41 is driven to dispense frying oil 10 from the return flow path 40 into the oil vat 2, the frying oil 10 discharged from the nozzle 42 flows along the inclined bottom plate 20, causing fried debris 18 accumulated on the inclined bottom plate 20 to fall toward the outlet at the deepest part. This facilitates the discharge of fried debris 18. Additionally, this prevents the low-temperature frying oil dispensed from the reserve tank 4 into the oil vat 2 from being mixed with the high-temperature frying oil in the upper oil vat 2, which is also suitable for continuing deep-frying cooking in the upper oil vat 2a.

[0029] Figure 4 is a plan view of the oil vat 2 as viewed from above. The bottom of the oil vat 2 is formed by the intersection of four inclined bottom plates 20, with the outlet 50 provided at the center, at its deepest point. The return flow path 40 is connected to two corners of the oil vat 2 that face each other across the outlet 50, and the nozzles 42 are provided at each position. The nozzles 42 branch in two directions to inject frying oil, and are configured to discharge frying oil 10 onto each of the two adjacent inclined bottom plates 20, as shown by the arrows in Figure 4.

[0030] By discharging the frying oil 10 from the return flow path 40 to all the inclined bottom plates 20 in this manner, a flow of the frying oil 10 toward the discharge outlet 50 occurs above each inclined bottom plate 20, so that the fried debris accumulated on these inclined bottom plates 20 can be swept away toward the discharge outlet 50. Therefore, when the discharge valve 6 is opened, the fried debris can be actively discharged into the discharge flow path 5.

[0031] As explained above, with a fryer to which the present invention is applied, even if a large amount of fried food is continuously cooked, resulting in a large amount of fried food residue being generated in the oil vat and the fried food residue accumulating on the inclined bottom plate of the lower oil vat, it is possible to remove the fried food residue from the oil vat while continuing frying in the upper oil vat, thereby improving the operating efficiency of the fryer during frying. [Explanation of symbols]

[0032] 1... fryer, 2... oil tank, 2a... upper oil tank, 2b... lower oil tank, 10... frying oil, 3... housing, 4... reserve tank, 5... discharge flow path, 6... discharge valve, 7... filter, 8... heater, 17... fried residue discharge button, 20... inclined bottom plate, 40... return flow path, 41... oil supply pump, 42... nozzle, 50... discharge port

Claims

1. A fryer that heats frying oil stored in an oil tank with a heater and deep-fries ingredients placed in the oil tank, an upper oil tank in which the heater is disposed and in which food ingredients are fried; a lower oil tank provided below the upper oil tank and continuous with the upper oil tank, the lower oil tank having a discharge outlet at its deepest portion for discharging fried food residue generated in the oil tank together with the frying oil, and having a plurality of inclined bottom plates inclined toward the discharge outlet; a water-cooling jacket provided around the lower oil tank and filled with cooling water to forcibly cool the frying oil in the lower oil tank; a discharge valve that opens and closes a discharge flow path connected to the discharge port; a reserve tank for removing fried debris from the frying oil discharged through the discharge valve and storing the frying oil after the fried debris has been removed; a return flow path having an oil supply pump and supplying the frying oil in the reserve tank to the lower oil tank; a control unit that manages the operation of the heater, the opening and closing of the discharge valve, and the operation of the oil injection pump; a fried residue discharge button that instructs the control unit to discharge fried residue that has settled in the lower oil tank during frying, In response to the operation of the fried residue discharge button, the control unit drives the oil pump to add a predetermined amount of frying oil from the reserve tank to the oil tank, and opens the discharge valve to discharge the same amount of frying oil from the lower oil tank.

2. 2. The fryer according to claim 1, wherein the return passage is connected to the lower oil tank above the inclined bottom plate.

3. 3. The fryer according to claim 2, wherein a nozzle is provided at a connection between the lower oil tank and the return flow path to guide the recycled frying oil to the inclined bottom plate.

4. 4. The fryer according to claim 3, wherein a plurality of the nozzles are provided corresponding to each of the inclined bottom plates.

5. 5. The fryer according to claim 4, wherein the control unit opens the discharge valve simultaneously with driving the pump.

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