Fryer

Abstract

To provide a fryer capable of collecting water in a reserve tank without returning the water to an oil tank even when a large amount of water released from a food material during frying is contained in frying oil without vaporizing, and preventing oxidation deterioration of the frying oil even in repeated use of the frying oil.SOLUTION: In the fryer 1 in which frying cooking is performed in an upper oil tank 2a while a lower oil tank 2b is forcibly cooled by a water cooling jacket, a reserve tank 4 for storing frying oil 10 discharged from the lower oil tank and a return flow passage 40 for pouring the frying oil in the reserve tank into the lower oil tank are provided. The reserve tank has a filter 7 for removing frying dregs from frying oil on the upper part, and the bottom plate in the reserve tank is inclined toward the deepest part to be a reserve part of frying oil, a suction pipe communicating with a return flow passage is arranged in the reserve part, and the tip of the suction pipe is arranged apart from the bottom plate of the reserve 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 is 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 deep-frying is allowed to settle in the lower oil tank and collected.

[0003] In particular, Patent Document 1 discloses a fryer that forcibly cools the lower oil tank by providing a water-cooled jacket that completely covers the lower oil tank. In this fryer, the cooling effect of the water-cooled jacket keeps the oil temperature in the lower oil tank below 60°C. Therefore, moisture released from ingredients in the high-temperature upper oil tank sinks to the lower oil tank due to the difference in specific gravity between the upper oil tank and the frying oil, and is retained in the lower oil tank without evaporating. This suppresses oil splashing caused by boiling of the frying oil, promotes the settling of fried food debris in the lower oil tank, and reduces oil stains in the kitchen. Furthermore, by minimizing the evaporation of moisture in the oil tank, it is possible to effectively prevent deterioration due to oxidation of the frying oil, thereby extending the frying oil replacement cycle. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 5901624 Summary of the Invention [Problem to be solved by the invention]

[0005] In many commercial fryers that continuously perform large amounts of deep-frying, an oil recovery tank is provided below the oil vat in the housing to enable cleaning of the oil vat and repeated use of the frying oil. For example, after the end of a day's cooking operations, the empty oil vat can be cleaned by draining all of the frying oil from the oil vat into the oil recovery tank. After cleaning is complete, the frying oil in the oil recovery tank can be returned to the oil vat, allowing the frying oil to be reused for frying.

[0006] In this regard, the fryer disclosed in Patent Document 1, as described above, is designed to easily retain moisture released from ingredients in the lower oil tank without evaporating, so the frying oil drained from the oil tank to the oil recovery tank retains a large amount of moisture. Therefore, if all of the frying oil in the oil recovery tank is returned to the oil tank after the cleaning work is completed, the moisture trapped in the frying oil will also be returned to the oil tank. Because the frying oil is agitated during the process of pouring it from the reserve tank into the oil tank, if the frying oil in the oil tank is heated again in that state, the moisture mixed in the frying oil will evaporate, which could accelerate deterioration of the frying oil.

[0007] Furthermore, in order to increase the number of times that frying oil can be reused, the frying oil is passed through a filter when it is discharged from the oil tank to an oil recovery tank, and the filter removes the fried debris. To filter out the fine fried debris floating in the frying oil, the filter needs to have a sufficiently fine mesh. However, if the filter has a fine mesh, it takes a long time for the frying oil to pass through the filter, which increases the time required for cleaning. Furthermore, there remains a concern that the moisture contained in the frying oil is not removed by the filter and may be mixed with the frying oil in the oil recovery tank. [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 collect moisture in a reserve tank without returning it to the oil tank, even when a large amount of moisture released from ingredients during deep-frying is contained in the frying oil without evaporating, and that can prevent oxidation and deterioration of the frying oil even when the frying oil is used repeatedly.

[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 ingredients placed in the oil tank, and includes: an upper oil tank in which the heater is disposed and in which the ingredients are deep-fried; a lower oil tank that is disposed below the upper oil tank and is continuous with the upper oil tank, and has a discharge outlet at its deepest part for discharging fried food residue generated in the oil tank together with the frying oil, and has a plurality of inclined bottom plates that slope toward the discharge outlet; a water-cooled jacket that is disposed around the lower oil tank and is filled with cooling water for forcibly cooling the frying oil in the lower oil tank; a discharge valve that opens and closes a discharge flow path connected to the discharge outlet; a reserve tank that stores frying oil that flows down from the oil tank through the discharge valve; and a return flow path that has an oil injection pump and feeds the frying oil in the reserve tank into the lower oil tank. The reserve tank has a filter at the top that removes fried debris from the frying oil flowing into the reserve tank, and the bottom plate inside the reserve tank is inclined toward the deepest part where the frying oil accumulates.A suction pipe that leads to the return flow path is located in the accumulation part, and the tip of the suction pipe is located away from the bottom plate of the reserve tank. [Effects of the Invention]

[0010] According to the present invention, the bottom plate of the reserve tank is inclined toward the deepest portion, which is the reservoir portion. Therefore, when frying oil is discharged from the oil tank into the reserve tank, the moisture contained in the frying oil gradually collects in the reservoir portion within the reserve tank. Furthermore, the tip of the suction pipe for returning the frying oil from the reserve tank to the oil tank is positioned away from the bottom plate in the reservoir portion. Therefore, when the oil supply pump is driven to suck up the frying oil from the reserve tank, some of the frying oil remains in the reserve tank without being returned to the oil tank. As a result, the moisture contained in the frying oil in the reserve tank is collected in the reservoir portion and remains in the reservoir portion without being sucked up by the suction pipe.

[0011] In other words, by temporarily discharging the moisture-containing frying oil from the oil tank into a reserve tank and then pouring the oil from the reserve tank back into the oil tank, the moisture contained in the frying oil can be collected in the reserve tank, making it possible to prevent deterioration of the frying oil due to oxidation as much as possible, even when the frying oil is used repeatedly. [Brief explanation of the drawings]

[0012] [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 front view showing a reserve tank of the fryer according to the embodiment. [Figure 4] FIG. 2 is a side view showing a reserve tank of the fryer according to the embodiment. [Figure 5] FIG. 2 is a plan view showing a reserve tank of the fryer according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0013] The flyer of the present invention will be described in detail below with reference to the accompanying drawings.

[0014] 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.

[0015] 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.

[0016] A mesh filter 7 is provided midway along the path that discharges the frying oil from the discharge flow path 5 to the reserve tank 4. As the frying oil flows into the reserve tank 4, the filter 7 captures the fried debris. The mesh size of the filter can be 20 to 50 mesh, with 30 to 40 mesh being preferred. While this depends on the diameter of the wire forming the filter, for example, the mesh size of a 50-mesh filter is approximately 0.279 mm, allowing fine particles of fried debris to pass through the filter. The reason for making the mesh size of the filter 7 coarse to collect only large fried debris is to increase the flow rate per unit time of the frying oil 10 passing through the filter 7 and thereby rapidly drain the frying oil 10 from the oil tank 2 to the reserve tank 4. Details of the reserve tank 4 will be described later.

[0017] 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.

[0018] 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., 60°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.

[0019] 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 10 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.

[0020] 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 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.

[0021] Figure 2 is a block diagram showing the control system of fryer 1. Fryer 1 is equipped with power supply unit 11 that receives power from an AC power source, and control unit 12, which has a built-in microprocessor, receives power from power supply unit 11 and controls the operation of oil supply pump 41, heater 8, and discharge valve 6. Temperature sensor 13 that measures the temperature of frying oil 10 in upper oil tank 2a is also connected to control unit 12, and while referring to the output signal of temperature sensor 13 at predetermined time intervals, control unit 12 commands power supply unit 11 to supply to heater 8 according to a pre-stored program so that frying oil 10 in upper oil tank 2a is maintained at a predetermined temperature (e.g., 180°C).

[0022] An operation panel 14 serving as a user interface is connected to the control unit 12. The operation panel 14 is equipped with an UP button 15 and a DOWN button 16 for inputting the cooking temperature, and a display unit 17 that shows the current temperature of the frying oil 10 in the upper oil tank 2a and the cooking temperature set using the UP button 15 and DOWN button 16.

[0023] The operation panel 14 is also provided with a drain button 18 that instructs the oil tank 2 to drain all of the frying oil 10 into the reserve tank 4, and an oil fill button 19 that fills the empty oil tank 2 with the frying oil 10 in the reserve tank 4. The drain button 18 is operated, for example, when it is desired to empty the oil tank 2 and clean it, and when this button 18 is operated, the discharge valve 6 is opened and all of the frying oil 10 in the oil tank 2 is drained into the reserve tank 4. The oil fill button 19 is operated when it is desired to transfer the frying oil 10 in the reserve tank 4 to the empty oil tank 2, and when this button 19 is operated, the oil fill pump 41 is started and approximately all of the frying oil 10 in the reserve tank 4 is poured into the oil tank 2, thereby filling the oil tank 2 with frying oil 10.

[0024] Furthermore, when replacing the used frying oil 10 in the oil tank 2 with new oil, the user operates the drain button 18 to drain the used frying oil 10 into the reserve tank 4, then replace the frying oil in the reserve tank 4 with new frying oil, and then operate the oil fill button 19 to fill the oil tank 2 with new frying oil 10. This allows the user to easily replace the frying oil 10 without having to lift the heavy container containing the frying oil 10.

[0025] The operation panel 14 is provided with a fried residue discharge button 30 that discharges fried residue that has accumulated in the lower oil tank 2b during deep-frying in the oil tank 2 out of the oil tank 2. When a user operates this fried residue discharge button 30, 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.

[0026] 3 to 5 are diagrams showing the reserve tank 4 in detail.

[0027] The reserve tank 4 is rectangular and has casters 42 on its bottom surface, and a handle 43 on its front surface, allowing it to be easily pulled out from below the housing 3 when a large amount of frying oil is stored therein. The capacity of the reserve tank 4 is set to be larger than the total amount of frying oil 10 in the oil tank 2, and in this embodiment is set to approximately 26 liters. The filter 7 described above is provided in the center of the top of the reserve tank 4, and the frying oil 10 discharged from the oil tank 2 passes through the filter 7 and flows into the reserve tank 4, where fried food debris is collected. The filter 7 has a handle 70, allowing the filter 7 to be removed from the reserve tank 4 to dispose of the collected fried food debris.

[0028] The bottom plates within the reserve tank 4 are composed of a bottom plate 44a inclined toward the left of the reserve tank 4 as shown in the front view of Fig. 3, a bottom plate 44b inclined toward the front of the reserve tank 4 as shown in the side view of Fig. 4, and a horizontal bottom plate 44c provided at the left end of the front side of the reserve tank 4 as shown in the plan view of Fig. 5. The bottom plate 44c is the deepest part of the reserve tank 4 and functions as a reservoir 45 where the frying oil 10 in the reserve tank 4 first and lasts to accumulate. In other words, as the amount of frying oil 10 in the reserve tank 4 decreases, it flows over the bottom plates 44a and 44b and collects in the reservoir 45.

[0029] A suction pipe 46 communicating with the return flow path 40 is inserted inside the reserve tank 4. This suction pipe 46 is disposed in the reservoir 45, and the tip of the suction pipe 46 is disposed away from the bottom plate 44c of the reserve tank 4, so that even when the oil injection pump 41 is started, the frying oil in the reserve tank 4 is not completely sucked up, and a small amount of frying oil remains in the reservoir. The suction pipe 46 is detachable from the reserve tank 4, and is removed from the reserve tank 4 when the reserve tank 4 is pulled out toward the user from the housing 3.

[0030] Furthermore, the reserve tank 4 always holds the amount of frying oil 10 that will be poured into the lower oil tank 2b when the fried residue discharge button 30 is operated, and this frying oil 10 is present in the reservoir 45. For this reason, the capacity of the reserve tank 4 is set larger than the capacity of the oil tank 2.

[0031] As already explained, when the drain button 18 or the fried residue discharge button 30 is operated, the frying oil 10 in the oil tank 2 is discharged into the reserve tank 4, and at that time, the fried residue that has accumulated on the inclined bottom plate 20 in the lower oil tank 2b is discharged from the oil tank 2 together with the frying oil 10. Relatively large fried residue mixed in the discharged frying oil 10 is collected by the filter 7, but fine fried residue and moisture are not captured by the filter 7 and flow into the reserve tank 4 mixed with the frying oil 10.

[0032] By storing the frying oil 10 in the reserve tank 4, fine fried debris and moisture mixed in the frying oil settle on the bottom plate of the reserve tank 4. For example, when a user presses the drain button 18 on the operation panel 14 after finishing work for the day, the frying oil 10 is discharged from the oil tank 2 to the reserve tank 4, and at the same time, the oil supply pump 41 is driven for a predetermined period of time to clean the oil tank 2 with the frying oil circulated from the reserve tank 4 to the oil tank 2. If the frying oil 10 discharged into the reserve tank 4 is kept in the reserve tank 4 until the next morning, the fine fried debris and moisture will have settled on the bottom plate of the reserve tank 4 by the time work begins the next day. At this time, the fried food residue will accumulate on the bottom plates 44a, 44b, and 44c of the reserve tank, but since the bottom plates 44a and 44b are inclined, water, which has a higher specific gravity than the frying oil, will flow over the bottom plates 44a and 44b and accumulate on the bottom plate 44c, which is the deepest part of the reserve tank 4.

[0033] At the start of business the next day, the user can press the oil supply button 19 on the operation panel 14 to return the frying oil 10 in the reserve tank 4 to the oil vat 2. At this time, when the oil supply pump 41 operates, the frying oil in the reserve tank 4 is sucked into the return flow path 40 by the suction pipe 46 arranged in the reservoir 45, and is poured into the oil vat 2 through the return flow path 40.

[0034] On the other hand, the tip of the suction pipe 46 for returning the frying oil 10 from the reserve tank 4 to the oil vat 2 is spaced apart from the bottom plate 44c, and a predetermined distance (for example, 5 mm) is provided between the suction pipe 46 and the bottom plate 44c. Therefore, when the oil supply pump 41 is driven to suck up the frying oil 10 from the reserve tank 4, at least a portion of the frying oil 10 present in the reservoir 45 remains in the reserve tank 4 without being returned to the oil vat 2. As a result, the moisture contained in the frying oil 10 in the reserve tank 4 is collected in the reservoir 45 and remains in the reservoir 45 without being sucked up by the suction pipe 46.

[0035] That is, in the fryer 1 of this embodiment, if the frying oil 10 containing moisture is temporarily discharged from the oil tank 2 to the reserve tank 4 and then poured from the reserve tank 4 into the oil tank 2 after a certain time interval, the moisture contained in the frying oil 10 will remain in the reservoir of the reserve tank 4, and only the frying oil from which the moisture has been removed can be poured from the reserve tank 4 into the oil tank 2.

[0036] In particular, the fryer 1 of this embodiment is structured so that moisture released from ingredients into the frying oil 10 during frying cooking can be easily collected in the lower oil tank 2b without evaporating by surrounding the lower oil tank 2b with a water-cooling jacket 22. As a result, the frying oil discharged from the oil tank to the reserve tank contains a large amount of moisture. Therefore, as described above, if the moisture contained in the frying oil 10 can be left in the reservoir of the reserve tank 4 and only the frying oil from which the moisture has been removed can be poured from the reserve tank 4 into the oil tank 2, the moisture released from the ingredients can be actively collected in the reserve tank 4 without evaporating in the oil tank 2. As a result, evaporation of moisture in the oil tank can be prevented, minimizing deterioration of the frying oil due to oxidation, thereby extending the life cycle of the frying oil and reducing the cost of frying cooking.

[0037] Furthermore, since the tip of the suction pipe is separated from the bottom plate 44c, fine fried food particles that accumulate on the bottom plates 44a, 44b, and 44c of the reserve tank 4 will not be poured into the oil tank along with the frying oil.

[0038] As explained above, according to the fryer 1 of the present invention, the frying oil 10 used for deep-frying in the oil tank 2 is temporarily discharged into the reserve tank 4, and then oil is refilled from the reserve tank 4 into the oil tank 2. This makes it possible to remove moisture released into the frying oil 10 from the ingredients during deep-frying into the reserve tank 4, thereby preventing oxidation and deterioration of the frying oil 10 during deep-frying as much as possible, lengthening the life cycle of the frying oil 10 until it needs to be replaced, and reducing the cost of deep-frying. [Explanation of symbols]

[0039] 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... display unit, 18... removal button, 19... oil supply button, 30... fried residue discharge button, 40... return flow path, 41... oil supply pump, 44a, 44b, 44c... bottom plate, 45... reservoir, 46... suction pipe

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 port 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 port; 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 storing the frying oil flowing down from the oil tank through the discharge valve; a return flow path having an oil supply pump and supplying the frying oil in the reserve tank to the lower oil tank; The reserve tank has a filter at its top for removing fried debris from the frying oil flowing into the reserve tank, and the bottom plate of the reserve tank is inclined toward the deepest part where the frying oil accumulates, A fryer characterized in that a suction pipe communicating with the return flow path is disposed in the reservoir, and the tip of the suction pipe is disposed away from the bottom plate of the reserve tank.

2. 2. The fryer according to claim 1, wherein the reserve tank has casters so that it can be pulled out from below the oil tank, and the suction pipe is detachable from the reserve tank.

3. 2. The fryer according to claim 1, wherein the filter is detachable from the reserve tank.

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