JP2001161571A - Oil level detecting system for fryer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an oil level detecting device capable of detecting the level of edible oil in an oil tank during heating foodstuffs for cooking in a fryer in order to prevent them from being poorly cooked due to drop of oil level or prevent no-oil heating when oil is used up. SOLUTION: A pneumatic-fluctuation detecting device 40 detects a change of air pressure in an oil level detection pipe 36 inserted into edible oil in the oil tank 12 of a fryer 10 at the open end thereof when the open end is exposed from the oil surface. The pneumatic-fluctuation detecting device 40 is, for example, of a diaphragm type, and is connected at the HIGH side thereof to a supply- air pressure detecting pipe 39, which is connected to an air supply pipe 38 for combustion air equipped with a fan 28 and to the base end of the oil level detection pipe 36, and is open at the LOW side thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for detecting an oil level of a fryer, and more particularly, to a cooking oil in an oil tank in a fryer using a heating method such as a submerged burner type, an infrared burner type, and a pulse combustion burner type. The present invention relates to an oil level detecting device for detecting that the oil level of the liquid has fallen below a reference level.

[0002]

2. Description of the Related Art Conventionally, various types of heating systems such as a submerged burner system, an infrared burner system, and a pulse combustion burner system have been generally known as this type of fryer. The filled cooking oil such as tempura oil is heated by these heating methods, and the ingredients to be cooked are put into the cooking oil to produce fried food.

[0003] In this case, the cooking oil is absorbed by the cooked food as the food is cooked, and the oil level gradually decreases. The cook then replenishes the cooking oil, but if he does not notice a drop in the oil level, cooking problems such as the upper part of the ingredients put into the cooking oil not entering the oil and not frying can occur. May occur (for example, in the case of a fried potato, the upper part of the potato in a special basket does not enter the oil and does not fry).

[0004] For example, the cooking oil is sometimes transferred to a filtering tank to remove oil residues and the like, and then returned to the oil tank for reuse. If the oil level is lowered due to an abnormality of the oil valve, or if the oil filling before use is insufficient, the fuel may be fired in an empty state.

Therefore, it is necessary to constantly monitor the height of the oil level. And, as a method, a float SW
An oil level sensor or oil pressure sensor such as a photo-sensitive, photosensitive SW (infrared ray) or electrode type is provided in the oil tank so that the detection signal can confirm that the oil level is at a predetermined level. And so on.

As another method, as shown in, for example, Japanese Utility Model Registration No. 2523728, an oil temperature rise rate is detected by a cooking oil temperature detection sensor provided in an oil tank, and a change in the oil temperature rise rate is detected. There has also been proposed an apparatus in which the oil level is determined based on the result.

[0007]

However, none of the detection methods is reliable, and none of them has actually been applied to a flyer. For example, in the float SW type, the float has a smaller buoyancy than water and the float becomes larger, and the pressure of the float increases at high temperature. In addition, although the oil temperature reaches 180 ° C., there is no magnetic lead SW excellent in heat resistance, and there is a problem that the sliding portion of the float is fixed with oil and causes malfunction.

Further, the photosensitive SW type has a problem in that the light emitting and receiving lenses are fogged by an oil film, and the electrode type has a problem that the oil is not energized unlike water. Further, the oil pressure sensor has good heat resistance, but has a problem of malfunction due to oil residue. Furthermore, in the case of Japanese Utility Model Registration No. 2523728 in which the oil temperature rise rate is exceeded by the detection signal from the oil temperature detection sensor, it is not possible to accurately detect that the cooking oil in the oil tank has decreased. there were.

An object of the present invention is to provide an oil level detecting device capable of accurately and reliably detecting the oil level of edible oil in an oil tank during cooking of a food to be cooked by a flyer. In this way, it is possible to prevent poor cooking of the food to be cooked due to a decrease in the oil liquid level during heating and cooking or empty heating due to lack of oil.

[0010]

According to a first aspect of the present invention, there is provided an apparatus for detecting an oil level of a flyer, wherein cooking oil in an oil tank heated by a burner is cooked. By feeding the food, the food to be cooked is cooked by heating, but during the cooking, the oil level of the edible oil in the oil tank is lowered, and the opening end of the oil level detecting tube is exposed from the oil level. At times, a change in air pressure in the detection pipe is detected by the air pressure fluctuation detecting means. Accordingly, if the combustion is automatically performed based on the air pressure fluctuation detecting means, or if measures such as informing a cook of the necessity of refueling by a buzzer are taken, the food to be cooked can be obtained. It is possible to avoid the occurrence of poor heating cooking and the occurrence of an empty-burning trouble due to lack of oil.

In this case, the oil level detecting device according to the second aspect uses a so-called single pressure type oil level detecting method. According to this device, the oil level of the edible oil in the oil tank is adjusted. When the oil level is lowered and the opening end of the oil level detection pipe is exposed from the oil level, the air pressure in the air supply pressure test pipe connected to the HIGH side of the air pressure change detector fluctuates to the atmospheric pressure side, The fluctuation value of the differential pressure is detected in a state where there is almost no difference from the air pressure on the LOW side which is originally opened to the atmospheric pressure by the air pressure change detector.

An oil level detecting device according to a third aspect of the present invention uses an oil level detecting method based on a so-called differential pressure method. According to this device, the oil level of edible oil in an oil tank is increased. When the opening level of the oil level detection pipe is exposed from the oil level, the air pressure in the first air supply pressure test pipe connected to the HIGH side of the air pressure change detector fluctuates to the atmospheric pressure side. The change in the pressure difference from the air pressure in the second air supply test tube on the LOW side of the air pressure change detector is detected.

Further, the oil level detecting device according to the fourth aspect also uses the oil level detecting method based on the differential pressure method. According to this device, the oil level of the edible oil in the oil tank is increased. When the open end of the oil level detection pipe is exposed from the oil level, the air pressure in the second air supply test pipe connected to the LOW side of the air pressure change detector fluctuates to the atmospheric pressure side. , Pneumatic pressure change detector HI
A change in differential pressure from the air pressure in the first air supply test tube on the GH side is detected.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Various preferred embodiments of the present invention will be described below in detail with reference to the drawings. First, FIG.
1 shows a schematic configuration of a submerged burner type flyer according to a first embodiment of the present invention. This submerged burner type flyer 10 is provided with a submerged pipe 14 for heating a heat exchanger type oil which is formed in a loop shape at the inner bottom of an oil tank 12.
An air chamber 16 having a mixing chamber for fuel gas and combustion air is attached to the outer wall surface of the oil tank 12.

FIG. 2 shows a detailed structure of the burner heating mechanism in and near the air chamber 16. A gas combustion chamber 18 is provided at the base end of the immersion pipe 14, and the oil tank 12 is provided. A mixing chamber 20 for fuel gas and combustion air is provided on the outer wall side of the fuel cell.
The original solenoid valve 24 is provided in the gas supply pipe 22 for supplying fuel gas to the
And a main solenoid valve 26. A sirocco fan type electric air supply fan 28 for supplying combustion air is connected to the air chamber 16, and the combustion air supplied by the air supply fan 28 is supplied to a ventilation chamber provided in a partition of the mixing chamber 20. The gas is introduced into the mixing chamber 20 through the port 30, mixed with the fuel gas, and sent to the gas combustion chamber 28. The gas combustion chamber 18 is provided with an igniter 32 for gas ignition and a frame rod (not shown) for detecting the presence or absence of a flame. Oil tank 1
An oil temperature detection sensor 34 for detecting the heating temperature of the edible oil is provided on the inner wall surface 2.

In the submerged burner type flyer 10, the opening end of the oil pipe 36 for detecting the oil level whose tip is bent in a U-shape is inserted into the oil level in the oil tank 12 from above. The base end of the oil pipe 36 is connected to an air supply pipe 38 for combustion air by the air supply fan 28 via an air supply pressure measurement pipe 39. The HIGH of the diaphragm type pneumatic pressure fluctuation detector 40 for detecting that the oil level is lower than the opening at the tip of the oil pipe 36.
The side is connected to the oil pipe 36 via the supply pipe pressure tube 39, and the LOW side is open to the atmosphere.

In the immersion tube burner type flyer 10 configured as described above, when the power switch is turned on, the air supply fan 2
8 is activated to be in a pre-purge state, the original solenoid valve 24 and the main solenoid valve 26 are sequentially opened, and the ignition device (igniter 3) is opened.
Combustion is started by the operation of 2). Then, the ON / OFF operation of the combustion is continued by the signal from the oil temperature detection sensor 34, and the oil temperature of the edible oil in the oil tank 12 is controlled to a constant temperature.

[0018] Therefore, the oily liquid
The detection operation when the surface comes down is shown in the timing chart of FIG.
According to the chart, the oil level is now
In the position higher than the open end, the open end of the oil pipe 36
It is assumed that it is in a state of being immersed in oil. At this time, the sky
The pressure value on the HIGH side of the pressure fluctuation detector 40 is 30 mmH ₂
If O, the pressure value on the LOW side is at atmospheric pressure,
0mmH₂O, and thus the air pressure difference is 30-0 =
About 30mmH₂O will be detected.

However, assuming that the opening end of the oil pipe 36 is exposed to the outside air from the oil level due to the decrease in the oil level, the pressure value of the pneumatic pressure fluctuation detector 40 on the HIGH side is called atmospheric pressure. That is, since the air supply pressure by the air supply fan 28 is generated, it indicates about 10 mmH ₂ O, and the pressure value on the LOW side of the air pressure fluctuation detector 40 is about 0 mmH ₂ O at atmospheric pressure. Air pressure difference is 10-
0 = 10 mmH ₂ O will be detected.

Therefore, for example, the detection value of the air pressure difference detected by the air pressure fluctuation detector 40 is set at 20 mmH ₂ O as a threshold value, below which it is determined that the oil level has decreased, and the combustion signal is determined based on the detection signal. , Or a warning to the cook (buzzer or the like) is taken to take action. In addition, when the pressure difference is reduced even though the oil level is not low, the air supply fan 28 may fail and the combustion air may not be sufficiently sucked. It is useful.

Incidentally, in this case, if the opening end of the oil level detecting tube 36 is provided close to the heating immersion tube 14 in the oil tank 12, the heating of the edible oil is started when the burner is ignited. The oil solids adhering to the opening end of the oil level detection pipe 36 are melted in a short time, and it is possible to quickly shift to the oil level detection system.

Next, FIGS. 4 and 5 show a schematic configuration of an infrared burner type flyer as a second embodiment.
In the infrared burner type flyer 50, a ceramic plate 52 is provided on the outer bottom surface of the oil tank 12, a gas burner 54 is provided on the lower surface thereof, and the ceramic plate 52 is red-heated by the gas burner 54, and the cooking oil in the oil tank 12 is heated by the heat. This infrared burner type flyer 5 is used for heating.
Even at 0, the base end of the oil pipe 36 for detecting the oil level is connected to the air supply pipe 38 for the combustion air by the air supply fan 28, and the HIGH side of the air pressure fluctuation detector 40 is also connected to the oil pipe 36. While being connected, the LOW side is open to the atmosphere, and has a configuration similar to that of the first embodiment shown in FIGS.

Therefore, the timing chart shown in FIG. 3 is also applied to the infrared burner type flyer 50 when the oil is sufficiently in the oil tank 12 and the oil level is higher than the oil pipe 36. When the oil pressure decreases and the oil level becomes lower than the oil pipe 36 and the open end of the oil pipe 36 appears on the oil liquid level, the differential pressure decreases and the detection signal becomes higher. , The combustion is stopped or a buzzer alarm is issued.

FIG. 6 shows a schematic configuration of a submerged burner type flyer according to the third embodiment. The configuration of the burner portion of the immersion tube burner type flyer 60 is the same as that of the immersion tube burner type flyer 10 shown in FIG. 1, so that the description of that portion will be omitted. The base end of an oil pipe 36 inserted into the oil level is connected to a combustion air supply pipe 38 by an air supply fan 28, and a branch pipe 62 branched from an intermediate portion of the oil pipe 36 is used as a diaphragm-type empty pipe. It is connected to the HIGH side of the pressure fluctuation detector 40, while the L of the air pressure fluctuation detector 40 is
The OW side and the downstream side of the connection part of the oil pipe 36 of the air supply pipe 38 are connected by a differential pressure detection pipe 64.

FIG. 7 shows a timing chart of the oil level inspection by the immersion tube burner type flyer 60. When the oil is sufficiently filled at the time of starting the combustion, the air pressure fluctuation detector The pressure value on the HIGH side of 40 is 30 mmH ₂ O and the pressure value on the LOW side is 20 mmH ₂ O
Then, the differential pressure of 10 mmH ₂ O is detected.

When the oil level drops and the tip of the oil pipe 36 appears from the oil level, the H level of the air pressure fluctuation detector 40
The pressure value on the IGH side becomes atmospheric pressure, and the air pressure rises by 10 mmH
_Since the pressure value on the ₂ O and LOW sides is 20 mmH ₂ O without change, the differential pressure is 10−20 = −10 mmH ₂ O.

Therefore, for example, if it is determined that the oil is sufficiently filled at a differential pressure of 5 mmH ₂ O or more and the oil is insufficient at a differential pressure of 5 mmH ₂ O or less, it is possible to accurately determine whether the oil is sufficient or not. The Rukoto. Also, in this case, when the pressure difference is reduced even though the oil level is not low, the combustion air is not sufficiently sucked due to the failure of the fan, so that the air pressure fluctuation detector 40 is connected to the HIGH side. It is conceivable that the LOW side pressure difference could not be obtained sufficiently, which is useful for detecting a fan failure or finding a blockage of the exhaust system.

Next, a fourth embodiment will be described. FIG. 8 shows an example in which the present invention is applied to a pulse combustion burner type flyer 70. A pulse combustion chamber 72 and a tail pipe 74 bent in a loop are provided on the inner bottom of the oil tank 12, and an air chamber 76 is provided on the outer wall surface of the oil tank. Is attached. A mixing chamber of fuel gas and combustion air is provided in the air chamber 76, and the fuel gas supplied via a gas supply pipe is supplied to the mixing chamber via a Harappa valve.
An electric air supply fan 28 such as an illustrated sirocco fan or the like
As a result, the combustion air is supplied to the mixing chamber through the illustrated air supply muffler 78 and the air supply pipe 38, and is supplied to the pulse combustion chamber 72 as an air / fuel mixture. Although not shown, the gas supply pipe is provided with a main solenoid valve and a main solenoid valve, and
It is well known that an igniter for gas ignition and a frame rod for detecting the presence or absence of a flame are provided in 2. An oil temperature detection sensor 34 is provided on the inner wall surface of the oil tank 12.
Is provided.

In this pulse combustion burner type flyer 70, the tip opening of the oil level detecting pipe 36 whose tip is bent in a U-shape is set in a state where it is inserted into the oil level in the oil tank 12 from above, and the oil is set. The base end of the liquid level detection tube 36 is connected to a combustion air supply tube 38 by the supply fan 28.
A branch pipe 80 branched from the oil level detection pipe 36.
Is connected to the LOW side of the diaphragm type air pressure fluctuation detector 40, and the air supply located on the HIGH side of the air pressure fluctuation detector 40 and the upstream side of the air supply pipe 38 of the combustion air by the air supply fan 28. The base end of the muffler 78 is connected by a differential pressure detection tube 82. An intake nozzle 84 (diameter: about 1.0 mm) for protecting the diaphragm when the air pressure in the oil level detection pipe 36 is suddenly changed is provided at an intermediate position of the oil level detection pipe 36. I have.

According to the pulse combustion burner type flyer 70 thus constructed, the oil tank 12 is now sufficiently filled with edible oil, and the opening of the tip of the oil level detection pipe 36 is located at the oil level. It is assumed that the combustion is started in the state of. The timing chart will be described with reference to FIG. 9. When the combustion starts and the fan starts to drive and enters the pre-purge state, the HIGH side of the air pressure fluctuation detector 40 is set to about 60 mm.
H ₂ O, the LOW side is about 40mmH ₂ O, 60-
A differential pressure of 40 = about 20 mmH ₂ O is obtained.

When this enters the ignition state, the pressure difference slightly fluctuates, and a negative pressure is generated in the pulse combustion chamber 72, so that the LOW side of the air pressure fluctuation detector 40 becomes low, and accordingly, the HIGH side and the LOW side The pressure difference becomes large, indicating a value of about 30 mmH ₂ O. Thereafter, in a normal combustion state, the HIGH side is −15 mmH ₂ O, and the LOW side is −35 m.
Assuming mH ₂ O, −15 − (− 35) = about 20 mmH
₂ O, and a differential pressure state at the same level as in the pre-purge stage is obtained.

When the oil in the oil tank decreases and drops below the open end of the oil pipe 36, the LOW side of the air pressure fluctuation detection pipe 40 becomes the same level as the atmospheric pressure, and is about -10 mmH _2.
Only O is detected as a differential pressure. Therefore, the threshold value of the differential pressure fluctuation by the air pressure fluctuation detector 40 is set to 0 to 10 mmH ₂ O.
Then, when the opening end of the oil level pipe 36 is exposed from the oil level, this is accurately grasped, and measures such as stopping the combustion and warning by a buzzer can be taken.

FIG. 10 shows a timing chart when the edible oil in the oil tank 12 is low from the beginning and the combustion is started in a state where the oil level is low. in this case,
In the pre-purge stage, the HIGH side of the pneumatic pressure fluctuation detector 40 is about 60 mmH ₂ O, and the LOW side is about 10 mmH ₂ O since it is originally in the atmosphere.
0-10 = 50 mm H ₂ O, and the addition becomes 40mmH ₂ O by variations in differential pressure in the ignition phase.

When the combustion state is entered, the HIGH side of the air pressure fluctuation detector 40 is set to -20 mmH ₂ O, LO
The W side is −10 mmH ₂ O, and the differential pressure is −20−
(−10) = − 10 mmH ₂ O Therefore, the air pressure fluctuation detector 40 detects that the oil level is low, and takes measures such as stopping combustion. Therefore, in this case, although the oil level is not detected to be low at the pre-purge stage, the combustion is immediately stopped when the combustion is started.

The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention. For example, a diaphragm type air pressure detector was used as the air pressure detector used in each of the above embodiments, but the point is that the air pressure in the oil level detection pipe was released from the reduced pressure state by the suction fan to the atmospheric pressure. Any means may be used as long as it detects a change in air pressure at the time, and a means such as providing an air pressure sensor directly in the oil level detecting pipe may be used. In addition, the above embodiments have been described with reference to the example of heating and cooking food ingredients with edible oil, but the present invention is not limited thereto.
For example, the present invention can be applied to oil (oil) heat treatment of a metal material.

[0036]

According to the apparatus for detecting the oil level of a fryer according to the present invention, for example, when the oil level of edible oil in an oil tank used for cooking food is reduced during cooking or preparation, Since it is automatically detected that the oil level has dropped below the reference level, there is an advantage in that poor cooking of the food due to the drop in the oil level and empty heating are effectively prevented.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a submerged burner type flyer according to a first embodiment of the present invention.

FIG. 2 is a view showing a burner heating structure of the flyer shown in FIG. 1;

FIG. 3 is a timing chart illustrating an oil level detection state by the submerged burner type flyer.

FIG. 4 is a schematic configuration diagram of an infrared burner type flyer according to a second embodiment of the present invention.

FIG. 5 is a view showing a burner heating structure of the flyer shown in FIG. 4;

FIG. 6 is a schematic configuration diagram of a submerged burner type flyer according to a third embodiment of the present invention.

FIG. 7 is a timing chart illustrating an oil level detection state by the immersion tube burner type flyer shown in FIG. 6;

FIG. 8 is a schematic configuration diagram of a pulse combustion burner type flyer according to a fourth embodiment of the present invention.

FIG. 9 is a timing chart illustrating an oil level detection state by the pulse combustion burner type flyer shown in FIG. 8;

FIG. 10 is a timing chart illustrating an oil level detection state by the pulse combustion burner type flyer shown in FIG. 8;
It is a figure explaining the case where an oil level is low from the beginning.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Immersion tube burner type flyer 12 Oil tank 14 Immersion tube 28 Electric air supply fan 36 Oil pipe (oil level detection tube) 38 Air supply tube 39 Supply air pressure test tube 40 Air pressure fluctuation detector 50 Infrared burner type flyer 60 Immersion tube burner type Flyer 64 Differential pressure detecting tube 70 Pulse combustion burner type flyer 82 Differential pressure detecting tube 84 Intake nozzle

Claims (4)

[Claims] In a flyer provided with heating means for heating edible oil in an oil tank by a burner and air supply means for supplying combustion air to the burner by a fan, an oil level is detected on the edible oil in the oil tank. A fryer having an air pressure fluctuation detecting means for detecting a change in air pressure in the detection pipe when the opening end of the pipe is inserted and the opening end of the oil level detection pipe is exposed from the oil level. Oil level detector. 2. The air pressure fluctuation detecting means is a diaphragm type air pressure change detector, and the air pressure change detector HI
An air supply pressure test tube connected between the GH side and an air supply tube for combustion air by the fan, and a base end of the oil level detection tube connected to the air supply pressure test tube; LOW
The oil level detecting device for a flyer according to claim 1, wherein the side is open. 3. The air pressure fluctuation detecting means is a diaphragm type air pressure change detector, and the air pressure change detector HI
A first air supply pressure test tube is connected between the GH side and the upstream side of the combustion air supply pipe by the fan, and the LOW side of the air pressure change detector and the combustion air supply pipe by the fan are connected. The second air supply pressure test tube is connected to the downstream side, and a base end of the oil level detection tube is connected to the first air supply pressure test tube. Oil level detection device of the flyer. 4. The air pressure fluctuation detecting means is a diaphragm type air pressure change detector, and the air pressure change detector HI
A first air supply pressure test tube is connected between the GH side and the upstream side of the combustion air supply pipe by the fan, and the LOW side of the air pressure change detector and the combustion air supply pipe by the fan are connected. The second air supply pressure test tube is connected to the downstream side, and a base end of the oil level detection tube is connected to the second air supply pressure test tube. Oil level detection device of the flyer.