JP2007187416A - Combustion burner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent extra discharge of fuel when determining non-ignition by rapidly determining ignition in a second stage immediately after the ignition of a burner. <P>SOLUTION: The burner 5 is constituted to be ignited by an igniter 38, and a flame current during combustion is detected by a frame rod 40. In determining ignition or misfire from the high-low of a voltage value converted from the detection value, detection is started by the frame rod 40 by applying voltage to the igniter 38 when driving an electromagnetic pump 46 for supplying fuel. Ignition is determined if rising voltage values D2a, D2b, D2c higher than the voltage value D1a are detected, in the second stage D2 of detection after detecting, over a predetermined time, the voltage value D1a converted from the detection value of applied current of the igniter 38 in a first detection stage D1. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a combustion burner and can be used for a grain dryer or the like.

In the grain dryer, the igniter is discharged to the fuel and ignited, and the flame current during combustion is detected by the flame rod and converted into a voltage value. Whether the voltage level falls below a predetermined value, ignition or non-ignition is performed. It is configured so that the ignition igniter is temporarily turned off when the change in detected voltage value after fuel supply reaches a predetermined value or less, and the converted voltage value based on the detected value of the frame rod is less than the threshold value It is known that the presence or absence of ignition is determined by determining whether or not it is (Patent Document 1).
JP 2000-230716 A

  In the case of the ignition determination device as described above, it takes time until the voltage value becomes a predetermined value or less, and the ignition determination becomes slow, and if non-ignition is repeated at the start of combustion, the combustion fuel is excessively added to the burner. There arises a problem of discharging. In addition, if it is configured to remove the excessively discharged fuel by providing a drain, there is a problem that the cost increases.

  Accordingly, the present invention is intended to speed up the ignition determination and eliminate such problems.

  According to the first aspect of the present invention, in the combustion burner that burns by discharging the igniter (38) to the fuel supplied from the electromagnetic pump (46), a flame rod (40) that converts the voltage value when detecting a flame during combustion is provided. In determining ignition based on the level of the voltage value detected by the frame rod (40), the voltage value (D1a) detected after the start of combustion is higher than the detected voltage value (D1a) of the frame rod (40) detected before the start of combustion. The combustion burner is characterized in that the ignition determination means (49) determines that the ignition is performed when D2a, D2b, D2c) rises within a set time after the start of combustion.

  According to the above configuration, when the electromagnetic pump (46) is driven to supply fuel and the igniter (38) is discharged, combustion starts. In the detection first stage (D1) before the start of combustion, the flame rod (40) detects the voltage value (D1a) of the igniter (38) over a predetermined time of about 2 seconds and then starts the subsequent combustion. When a rise voltage value (D2a, D2b, D2c) higher than the voltage value (D1a) based on the applied current is detected for a predetermined short period of time (for example, about 3 seconds) in (D2), it is determined that ignition has occurred.

  The invention of claim 1 can make an ignition determination in the second stage (D2) immediately after ignition of the burner (5), and can make an ignition determination quickly. Therefore, it is possible to prevent excessive fuel discharge at the time of non-ignition determination.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
First, the whole structure of the grain dryer provided with this invention is demonstrated based on FIG.1 and FIG.2.

  Reference numeral 1 denotes a machine frame of a grain dryer. In the machine frame 1, a storage chamber 2, a drying chamber 3, and a grain collection chamber 4 are sequentially arranged from the upper side to the lower side. In the drying chamber 3, grain flow passages 9, 9 are formed between a hot air chamber 6 leading to a burner cylinder having a burner 5 and an exhaust air chamber 8 leading to a fan cylinder having a suction exhaust fan 7. , 9 is configured such that the grain is fed out by a predetermined amount by reciprocating rotation of the feeding valves 10, 10 provided at the lower part of the, 9 and dried by soaking the grain in hot air.

  On the outside of the machine frame 1, an elevator 11 is erected for returning the grains collected in one side of the cereal collection chamber 4 to the storage chamber 2. In this elevator 11, a bucket belt 13 is wound around a drive pulley 12 a and a driven pulley 12 b that are vertically pivoted, and the dried grain is transferred to one side by a lower conveying device 14 provided at the bottom of the cereal collection chamber 4. 11 is configured to transfer whipped grains. Grains that have been cerealed by the elevator 11 are supplied to the starting end side of the upper conveying device 16 from the threshing spout 15 of the elevator 11, and are further fed laterally by the upper conveying device 16 to the upper central portion of the storage chamber 2. It is configured so as to be sent to the rotating diffusion plate 18 provided and diffused and dropped into the storage chamber 2.

  The grain circulation system composed of the elevator 11, the lower transport device 14, and the upper transport device 16 is driven by an elevator motor (not shown) disposed on the upper frame of the elevator 11. That is, two drive belts (not shown) are wound around a drive pulley of an elevator motor (not shown), the upper conveying device 16 is driven by one drive belt (not shown), and the other drive belt (not shown). ) Drives the drive pulley 12a, bucket belt 13 and driven pulley 12b of the elevator 11.

  In addition, an intake port (not shown) is provided in the left and right interval portions of the ascending and descending strokes of the bucket belt 13 on the wall surface of the vertically middle part of the elevator 11, and a moisture meter is provided below the intake port (not shown). 26 is detachably disposed. The moisture meter 26 has a known configuration in which, for example, one sample grain is compressed and pulverized between a pair of electrode rolls, and the resistance value is electrically processed to convert it into a moisture value of the grain.

Next, the burner 5 will be described with reference to FIGS.
The burner 5 is a vaporization type burner, and a combustion cylinder 28 is provided on the front side of the casing 27, a burner motor 29 is provided in the casing 27, and an inverse conical diffuser is provided on the motor shaft 30 protruding forward of the burner motor 29. 31 is attached, a vaporizing cylinder 32 is provided so as to cover the periphery of the diffusing body 31, and a guide plate 33 for guiding the atomized fuel is provided in an extended shape on the open side periphery of the vaporizing cylinder 32.

  Further, a fan 34 is disposed below the casing 27, and combustion air is sent from the fan 34 into the casing 27 through the air blowing guide cylinder 35. Further, the second blower cylinder 35 a extends from the casing 27 side toward the center of the combustion cylinder 28, and a combustion disk 36 is fitted and mounted on the front surface of the center of the combustion cylinder 28. Gas ejection holes 36a, ... are provided. The combustion cylinder 28 is formed with a bulging portion 28 a that bulges to the outer peripheral side when viewed from the front. The bulging portion 28 a is provided with an igniter 38 comprising a pair of electrode portions, and is supplied from a nozzle 39. The igniter 38 ignites the kerosene atomized fuel. Reference numeral 40 denotes a frame rod that detects the presence or absence of a combustion flame, and is configured to detect a flame current during combustion and output the flame current to the control unit.

  An electromagnetic pump 46 is provided above the blowing guide cylinder 35, fuel kerosene is supplied to the vaporizing burner 5 by driving the electromagnetic pump 46, and ignition and ignition combustion are performed by discharge of the igniter 38. Then, the detected hot air temperature of the hot air temperature sensor 47 is compared with the set hot air temperature, and the on-time drive of the electromagnetic pump 46 is changed and controlled according to the difference to adjust the fuel supply amount, so that the detected hot air temperature falls within a predetermined setting range. It is the structure which controls to become.

Next, a control block configuration will be described with reference to FIG.
A control unit 49 is provided above the burner cylinder 45 (shown in FIG. 1). On the input side of the control unit 49, an extension switch 51, a drying switch 52, a discharge switch 53, a stop switch 54, and a grain type switch 55 disposed on the operation panel 50 (shown in FIG. 1) via an input interface. The finish moisture setting switch 56, the amount setting switch 57, the drying time increase / decrease switch 58, the moisture meter 26, the frame rod 40, the hot air temperature sensor 47, and the outside air temperature sensor 60 are connected. Further, the elevator motor 19, the feeding valve motor 62, the electromagnetic pump 46, the burner motor 29, the fan motor 63 for driving the fan 34, the igniter 38, and the like are connected to the output side of the control unit 49 through an output circuit and driving means. ing.

  The burner drive signal includes an ON / OFF signal and a large / small supply signal of the electromagnetic pump 46, a rotation speed command signal of the burner motor 29, a rotation speed command signal of the fan motor 63, an energization signal of the igniter 38, and the like. The control unit 49 compares the preset temperature stored in advance with the hot air temperature detected by the hot air temperature sensor 47 and periodically turns on the electromagnetic pump 46 so that the difference is small. Change and control the signal length.

Next, the operation of the grain dryer will be described.
A predetermined amount of grain is put into the storage chamber 2 using the elevator 11 from the holding hopper. Next, the grain type, the dry finish moisture value, etc. are set and the drying operation is started. Grains in the storage chamber 2 flow through the drying chamber 3, bathed in hot air, and flow down to the cereal collection chamber 4. The cereal dried by the hot air is transferred to one side by the lower conveying device 14, then cerealed by the elevator 11, taken over by the upper conveying device 16 and circulated again to the storage chamber 2, and undergoes a tempering action for a while. When the finishing moisture value is reached while repeating such a process, the drying operation is finished.

  In the drying operation, the burner 5 starts combustion by supplying the fuel supplied from the electromagnetic pump 46 to the igniter 38 and discharging it to ignite. That is, the vaporizing cylinder 32 is rotated by the rotation of the burner motor 29, and the fan 34 is rotated by the rotation of the fan motor 63 to introduce combustion air. Further, the fuel from the nozzle 39 is atomized while colliding with the diffusing body 31 rotating at a high speed, diffuses and flows along the inner peripheral surface of the vaporizing cylinder 32, is guided to the outer peripheral side by the guide body 33, and is ignited by the igniter 38. Ignited. Next, the atomized fuel that moves on the inner peripheral surface of the vaporizing cylinder 32 by the radiant heat generated by the combustion flame is gasified and guided to the back surface of the combustion disc 36, and is ejected from the surface to the front side and burned with blue fire.

Next, a configuration for determining that the ignition of the frame rod 40 has disappeared will be described with reference to FIGS.
When the drying switch 52 is turned on to start the drying operation, the burner motor 29 and the fan motor 63 are turned on, the igniter 38 is turned on, the fuel supply electromagnetic pump 46 is turned on, and the drying operation is started.

  When the detected value of the frame rod 40 was converted into the voltage value at the start of the drying operation, the following technical knowledge was obtained. That is, as shown in FIG. 8, when detection is started by the frame rod 40 from the start of driving of the electromagnetic pump 46, the application of the frame rod before the start of combustion (non-combustion state) is performed for about 2 seconds in the first stage (D1). The voltage value (D1a) is detected, and in about 3 seconds of the second stage (D2), the increased voltage values (D2a, D2b, D2c) higher than the voltage value (D1a) are detected, and the third stage (D3 ), A falling voltage value (D3a) that is lower than the rising voltage value (D2a, D2b, D2c) is detected, and this falling detection voltage value (D3a) sequentially decreases according to the stability of the combustion state, and reaches a predetermined voltage. The technical knowledge that it was stabilized at the value D4a and the state of the fourth stage (D4) continued was obtained. The ignition determination device of the present invention has been made based on such technical knowledge.

  In determining the ignition of the burner, the ignition is determined at the stage where the increased voltage values (D2a, D2b, D2c) in the second stage (D2) are detected. That is, the frame rod 40 detects a part of the initial discharge of the igniter 38 in the second stage (D2) and rises by a predetermined value from the voltage value (D1a) in the first stage (D1) before the start of combustion. The step of detecting the voltage value (D2a), the step of detecting the rising voltage value (D2b) for a predetermined time (for example, about 2 seconds), or the rising voltage value (D2b) at the end of the second step (D2) ) When a falling current value (D2c) that has fallen by a predetermined value is detected, or when the initial rising voltage value (D2a) and the falling voltage value (D2c) at the end of the second stage (D2) are both detected. Judged as ignition.

  In the second stage (D2), it is presumed that the detected voltage value of the frame rod 40 is added using a part of the discharge of the igniter 38 or a flame ignited by discharge noise as a conductor. In the conventional device, since the fall voltage value (D3a) in the third stage (D3) is stabilized and judged to be ignited at the stage of the fourth stage D4 where it falls to the predetermined value D4a, the ignition judgment is delayed. In this embodiment, it takes at least about 20 seconds from the start of combustion. Therefore, if non-ignition is repeated at the start of drying, excess combustion fuel will be discharged, and even if ignited, there will be a risk of fire due to the excess fuel being ignited. If it was removed, there was a problem that increased the cost.

  However, as described above, the second stage (D2) in the early stage of ignition, that is, the ignition determination can be made in a short time (about 5 seconds) from the start of combustion, and the ignition determination becomes quick and within a predetermined time. If the ignition determination is not made, the drive of the electromagnetic pump 46 is stopped, so that excessive discharge of fuel can be avoided and the above-mentioned problem can be solved.

  Further, the ignition determination may be performed as shown in FIG. That is, at the initial stage of the second stage (D2), when detecting the rising voltage value (D2a) rising from the voltage value (D1a) of the non-burning frame rod 40 of the first stage (D1), the moving average When the rising curve M with a predetermined slope or more is obtained, or when the falling voltage value (D2c) is smoothed with a moving average at the end of the second stage (D2) to obtain the falling curve with a predetermined slope or more. Then, it is determined that the ignition has occurred.

By providing a plurality of ignition determination criteria in this manner, erroneous detection due to noise or the like can be prevented and accurate ignition determination can be performed.
Further, the ignition determination may be performed as shown in FIG. That is, the average rising voltage value (D2d) is calculated by the moving average of the rising voltage value (D2b) in the second stage (D2) for a predetermined time, and the average rising voltage value (D2d) is calculated in the first stage (D1). When the voltage value (D1a) of the frame rod 40 is increased by a predetermined value N or more, it may be determined that ignition has occurred. This makes it possible to make an accurate ignition determination.

Next, the determination that the flame by the frame rod 40 has been extinguished will be described based on FIG.
In determining that the flame of the burner 5 has been extinguished by the frame rod 40, it is determined that ignition has occurred when the rising voltage value (D2a, D2b, D2c) in the second stage (D2) is detected, and a predetermined time has elapsed from the ignition determination. When (for example, 3 seconds) elapses, the determination that the fire is extinguished is started. When the flame rod 40 detects the falling voltage value (D3a) in the combustion state in the third stage (D3) or the stable combustion time in the fourth stage (D4), it is determined that ignition has occurred, and the ignition has disappeared even after the ignition determination. At the time of determination, when an applied current is supplied to the igniter 40 and the frame rod 40 detects a voltage value (D1a) converted from the applied current value of the igniter 38, it is determined that the fire is extinguished. With this configuration, it is possible to quickly determine that the fire has been extinguished.

  As shown in FIG. 8, the detection time of the increased voltage values (D2a, D2b, D2c) in the second stage (D2) is about 3 seconds in the present embodiment, and when this time period elapses, the third stage The process proceeds to a step (D3) for detecting a voltage drop (D3a) when the combustion is continued. And if it returns to the voltage value (D1) converted from a part of discharge of the igniter 38 of a non-combustion state from the fall voltage value (D3a) of the combustion state of a 3rd step (D3), it will determine with a fire extinguishing. With this configuration, it is possible to quickly and accurately determine that the fire has been extinguished.

  Further, a method for determining that preliminary ignition has disappeared may be added to the method for determining that ignition has been extinguished. The method for determining that the preliminary ignition has been extinguished is, for example, that a predetermined voltage value (for example, 3.3 V) or less is determined to be ignited, and that the predetermined voltage value (for example, 3.6 V) or more has been extinguished. Judgment. In this way, by using the method for determining that the preliminary ignition has been extinguished, it is safe to determine that the ignition has been extinguished even if the fire has extinguished during the third stage (D3). .

  Moreover, you may comprise as follows. In determining that the flame of the burner 5 has been extinguished by the frame rod 40, it is determined to be ignited if the increased voltage value (D2a, D2b, D2c) in the second stage (D2) is detected. Then, after the ignition determination, the igniter 38 is turned off, and the voltage value converted from the detection value of the frame rod 40 is detected. Add a preliminary method to

  In this way, by adding a method for determining that a fire has been extinguished, if the method for determining that one fire has been extinguished cannot determine that the fire has been extinguished due to noise or the like, It is safe to determine that the fire has been extinguished by the method for determining that the fire has extinguished.

Next, another embodiment of the method for determining that the ignition has disappeared will be described with reference to FIG.
When the control is started, if the flame rod 40 detects twice or more the voltage value at the time of non-combustion (for example, 4.5 V or more) within a predetermined time (for example, 10 seconds) after the electromagnetic pump 46 is turned on, it is determined as ignition. In addition, when a voltage value equal to or higher than the non-combustion voltage value (for example, 4.5 V or higher) is not detected twice within a predetermined time (for example, 10 seconds), it is determined as non-ignition (step S1).

  Next, when a predetermined time (for example, 3 seconds) elapses from the ignition determination, the determination that the fire is extinguished is started, and in the third stage (D3), the detected voltage value is a voltage value at the time of non-combustion (for example, 4.3 to 3). 4.5V), it is determined that the fire has been extinguished, and if the voltage value during non-combustion (for example, 4.3 to 4.5V) is not detected, it is determined that ignition has occurred (step S2). Next, if a predetermined voltage value (for example, 3.3 V) or less is detected within a predetermined time (for example, 30 seconds) after the electromagnetic pump 46 is turned on, it is determined that ignition has occurred, and the process proceeds to determination method 2 for determining that the fire has been extinguished. If the predetermined voltage value (for example, 3.3 V) or less is not detected within the predetermined time (for example, 30 seconds), it is determined that the fire has been extinguished (step S3).

Note that in the determination method 2 that the fire has been extinguished, it is determined that the fire has been extinguished when a predetermined voltage value (for example, 3.6 V) or more is detected.
By using the above-described determination method, it is possible to quickly determine whether the ignition at the initial stage of combustion has disappeared and determine whether the ignition has been continued when the combustion is continued.

  Moreover, you may comprise as follows. That is, in determining that the ignition has been extinguished, a voltage is applied to the igniter 38 for a predetermined time (for example, about 1 to 2 seconds) every predetermined time (for example, about 1 to 5 minutes) during combustion of the burner 5, and the flame rod 40 If the voltage value converted from the detected value detects the applied current value, it is determined to be ignited, and if it cannot be detected, it is determined that the fire has been extinguished. The reference value of the applied current value is set according to the rising gradient of the voltage value over a predetermined time.

Further, when the fire is extinguished, a display for prompting “cleaning the fuel disc 36 of the burner 5” may be displayed on the display unit (not shown).
If the combustion disc 36 or the vaporizing cylinder 32 of the burner 5 comes into contact with the frame rod 40 during the drying operation and the fire is extinguished for some reason, there is a problem that only fuel is discharged even though it is not combusted. However, with the above configuration, when the combustion disc 36 or the vaporizing cylinder 32 of the burner 5 is in contact with the frame rod 40, it is determined that the fire has extinguished because the applied current value is not detected. And the above problems can be solved.

The cutting front view of a grain dryer. A cut side view of a grain dryer. The perspective view of a burner. The side view which cut the burner partially. The top view of a burner. A cut side view of a part of a burner. Control block diagram. The graph which shows the detection voltage value of a flame rod. The graph which shows the detection voltage value of a flame rod. The graph which shows the detection voltage value of a flame rod. The graph which shows the detection voltage value of a flame rod. flowchart

Explanation of symbols

5 Burner 38 Igniter 40 Frame rod 46 Electromagnetic pump 49 Ignition determination means (control unit)
49 Judgment means (control part) that fire has gone out

Claims (1)

  In the combustion burner which burns by discharging the igniter (38) to the fuel supplied from the electromagnetic pump (46), a flame rod (40) whose voltage value is converted when a burning flame is detected is provided, and the flame rod (40) When the ignition is determined based on the level of the voltage value detected in step 4, the voltage values (D2a, D2b, D2c) detected after the start of combustion are higher than the detection voltage value (D1a) of the frame rod (40) detected before the start of combustion. A combustion burner, characterized in that the ignition determination means (49) determines that ignition occurs when it rises within a set time after the start of combustion.

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