JPH07127421A - Oil mist alarm device - Google Patents

Abstract

PURPOSE:To send out an alarm corresponding to a failure place so as to facilitate maintenance and to improve reliability. CONSTITUTION:An oil mist alarm device is provided with a step motor 1 for rotatory-driving the valve body 53 of a rotary valve for switching to communicate plural input ports P successively with an outlet port 54, a photo sensor 3 for detecting No. 0-port position of the valve body 53, a control part for sending out the alarm of valve failure when there is no detection signal from the photo sensor 3 for the specified time and stopping the step motor 1 to send out a mist alarm when a difference signal between the non-mist time output signal and mist detecting time output signal of a photocell 57 becomes the specified value or more, and a failure detecting part for sending out an alarm upon detecting the performance lowering of a photoelectric tube 55, the failure of the photocell, the lowering of supply voltage and the failure of an amplifier.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil mist alarm device for causing an oil mist in each crank chamber of a diesel engine or the like to sequentially flow into a photoelectric tube and issuing an alarm when the concentration of the oil mist exceeds a certain value.

[0002]

2. Description of the Related Art Conventionally, an oil mist alarm device of this type is known, for example, as shown in FIG. This alarm device connects all the 10 inlet ports provided in the casing 52 of the rotary valve 51 except the 0th port to each crank chamber (not shown) of the diesel engine, and has an AC motor and a reduction gear (not shown). The inlet port is sequentially switched to the outlet port 54 by the passage in the valve body 53 which is driven to rotate intermittently via the Geneva gear mechanism. Further, the inlet holes 55a, 55a of the photoelectric tube 55 having the tungsten lamp 56 as a light source at one end and the photocell 57 as a light receiving element at the other end are connected to the outlet port 54 of the rotary valve 51, while the outlet hole of the photoelectric tube is connected. The blower 58 is connected to 55b, the blower 58 and the bypass port 59 of the rotary valve 51 are connected by a bypass pipe 60, and the oil mist from each crank chamber is indicated by an arrow in the figure through an inlet port which is connected for switching. As shown, the blower 58 sucks into the phototube 55, while the oil mist at the other inlet port continues suction while bypassing the phototube. The output voltage of the photocell 57 is a constant value (alarm set value) due to the high concentration oil mist.
When the following occurs, an alarm lamp is turned on by a control unit (not shown) and rotation of the valve body 53 of the rotary valve is stopped so that the crank chamber number in which the mist abnormality has occurred can be confirmed.

Further, the control section detects the disconnection of the tungsten lamp due to the disconnection of the current supplied to the tungsten lamp 56, and turns on the alarm lamp. On the other hand, the tungsten lamp 56 and the photocell 5 are mixed with oil mist.
In order to prevent the lenses 61, 61 in front of 7 from being fogged, the front of both lenses is partitioned, and the outside air is supplied to this by a pump 62 to form an air curtain chamber.
The phototube 55 goes through the 0th port opened to the atmosphere every rotation.
Let fresh air flow inside. Further, since a slight drop in the output voltage of the photocell 57 cannot be avoided due to clouding due to mist adhesion of the lens during long-term use, the user periodically stops the valve body 53 at the 0th port position, The zero adjustment knob is turned while flowing fresh air to adjust the zero point of the photocell output.

[0004]

However, the above-mentioned conventional oil mist alarm device is designed to give an alarm by detecting the disconnection of the tungsten lamp 56, but another failure, that is, a decrease in the light amount of the lamp 56. Therefore, it is not possible to detect the deterioration of the performance of the photocell due to the dirt of the lens 61 due to the oil mist, the failure of the photocell 57 or the amplifier for amplifying the output signal of the photocell 57, and the power supply circuit, and to give an alarm accordingly. There is a problem that it is not easy to find and repair it. On the other hand, as a secondary problem, the alarm device
Since the valve body 53 of the rotary valve 51 is intermittently rotated via the Geneva gear mechanism, even if the number of crank chambers is 6 and the 7-9 inlet ports are unnecessary, these inlet ports can be used. Since the valve body temporarily stops, the time including feed and temporary stop is 4 seconds per port, 40 seconds for one rotation of the valve body, that is, the blind time becomes 40 seconds, and the mist detectable time of one crank chamber There is a problem that the ratio decreases. Further, since the tungsten lamp 56 is used for the photoelectric tube 55, the durability is poor, and the maximum amount of light is not immediately obtained when the power is turned on, and the photocell 57 is not obtained.
Output voltage is below the alarm setting. Therefore, although the alarm output is blocked by the CR circuit, this CR circuit does not work at the momentary power failure, so that there is a possibility that a false alarm is issued. In addition, since the entire alarm device is driven by an AC power supply of 100 to 230V, it is not suitable for a diesel engine of a ship that needs to secure the power supply even during blackout.
Furthermore, since the user manually adjusts the zero point of the photocell 57 in consideration of the combination characteristics of the lamp, the photocell, the amplifier, etc., there is a problem that the adjustment becomes difficult and time-consuming.

Therefore, an object of the present invention is to devise the structure of the control unit so as to cope with various failures and devise the driving means of the valve element of the rotary valve, so as to reduce the performance of the photoelectric tube, the rotary valve, The photocell, amplifier, and power supply circuit failure can be reliably detected, and an alarm corresponding to the failure can be issued to facilitate device maintenance, improve reliability, and reduce mist detection blind time. An object of the present invention is to provide an oil mist alarm device capable of accurately and quickly detecting oil mist over a long period of time and issuing an alarm.

[0006]

In order to achieve the above object, an oil mist alarm device according to a first aspect of the present invention is provided with a casing, and a predetermined number of inlet ports that can be connected to respective crank chambers of an engine are rotationally driven. A rotary valve that sequentially communicates with the outlet port of the casing through a passage in the valve body, a light source at one end, and a light receiving element at the other end,
In the rotary valve, the outlet port of the rotary valve is provided in the inlet hole, and a phototube having a blower connected to the exit hole is provided to detect the concentration of the oil mist in each crank chamber flowing in the phototube and issue an alarm. A step motor that drives the valve body to rotate, an origin sensor that detects the origin of the rotation angle of the valve body, and a rotary valve failure alarm when the detection signal from the origin sensor is not within a predetermined time. , Output signal of non-mist that is the output of the light receiving element when the inside of the photocell is in the non-mist state, and output at the time of mist detection that is the output of the light receiving element when the valve body is stopped at the position of the inlet port leading to the crank chamber When the difference signal with the signal exceeds a predetermined value, the step motor is stopped at that position and a mist alarm is issued, and When the output signal at the time of strike becomes equal to or lower than the first lower limit value corresponding to the permissible dirt in the phototube due to the mist, an alarm of deterioration of the performance of the phototube is issued, while the output signal at the time of detecting the mist corresponds to the high mist concentration. It is characterized by comprising a failure detection unit for issuing an alarm of a failure of the light receiving element when the output signal and the second lower limit value smaller than the first lower limit value are equal to or less than the second lower limit value.

An oil mist alarm device according to a second aspect is the alarm device according to the first aspect, further comprising a direct current power source of a constant voltage for supplying electric power, and an amplifier provided between the light receiving element and the control section. The failure detection unit, when the voltage of the DC power supply becomes lower than the lower limit voltage lower than the constant voltage, issues a power supply voltage drop alarm, and the output signal of the amplifier is output from an output signal corresponding to a high mist concentration. When it becomes less than the third lower limit value, which is also small, an alarm of an amplifier failure is issued.

[0008]

In the oil mist alarm device according to claim 1, a predetermined number of inlet ports provided in the casing of the rotary valve are connected to respective crank chambers of the engine, and an outlet port of the casing is connected to an inlet hole of the photoelectric tube. A blower is connected to the exit hole of the photoelectric tube. When the valve body of the rotary valve reaches the rotation angle origin, the origin sensor outputs a detection signal to the control unit, and the control unit receiving this signal starts the control of one rotation of the step motor, and the valve body moves to the crank. It makes one rotation while temporarily stopping at the entrance port leading to the room. Therefore, while the valve disc is temporarily stopped, the oil mist in the corresponding crank chamber flows through the passage and outlet port in the valve disc through the photoelectric tube by the blower, and the light from the light source passing through this oil mist is emitted. The receiving light receiving element outputs a smaller detection signal as the mist concentration is higher. By directly driving the valve element with the step motor, the cycle of one rotation is faster than in the case of intermittent driving via the Geneva gear mechanism, the blind time for mist detection can be shortened, and the probability of finding a mist abnormality in the crank chamber Can be increased.

The control unit outputs the output signal of the light receiving element when the inside of the phototube is in the non-mist state and the output of the light receiving element when the valve is stopped at the position of the inlet port leading to the crank chamber. When the difference signal from a certain mist detection output signal exceeds a predetermined value, the step motor is stopped at that position and a mist alarm is issued to inform the operator of the mist abnormality and its crank chamber number. Further, when the detection signal from the origin sensor is not within the predetermined time, the control unit issues a rotary valve failure alarm because the valve body is not rotating normally. On the other hand, when the non-mist output signal falls below the first lower limit value corresponding to the permissible dirt in the phototube due to mist, the failure detection unit issues a warning that the phototube performance is degraded, while the mist detection output signal is high. When the output signal corresponding to the mist concentration and the second lower limit value, which is smaller than the first lower limit value, become less than or equal to the second lower limit value, a warning of a light receiving element failure is issued. Thus, the deterioration of the photocell performance,
The operator is informed of the failure of the rotary valve and the light receiving element.

In the oil mist alarm device according to a second aspect of the present invention, an amplifier is provided between the light receiving element and the control unit, and power is supplied from a DC power source of a constant voltage. When the voltage of the DC power supply becomes equal to or lower than the lower limit voltage lower than the constant voltage, the failure detection unit issues a power supply voltage drop alarm, while the output signal of the amplifier is smaller than the output signal corresponding to the high mist concentration.
When it becomes lower than the lower limit, an alarm of amplifier failure is issued. Therefore, the operator is informed of further failure information of the alarm device that the power supply voltage has dropped and the amplifier has failed.

[0011]

The present invention will be described in detail below with reference to the embodiments shown in the drawings. FIG. 1 is a configuration diagram showing an example of an oil mist alarm device of the present invention. This alarm device integrates a solenoid valve with a rotary valve, and directly drives a valve body to rotate by a step motor having an origin sensor. The configuration is the same as that of the conventional example described in FIG. 5 except that a control unit, a failure detection unit, and the like are provided, and the same members as those in FIG. Casing 5 of rotary valve 51
The 10 inlet ports P provided in 2 are connected to the internal passage 53
The valve element 53, which is sequentially connected to the outlet port 54 via a, is rotationally driven by the step motor 1. On the drive shaft of the step motor 1, the rod 2 is fixed in the radial direction in order to detect the state where the valve body 53 is located at the 0th inlet port, that is, the origin of the rotation angle of the valve body, and corresponds to the 0th inlet port. A photo sensor 3 as an origin sensor for detecting passage of the rod 2 is provided at the position. Further, at the bottom of the casing 52, an electromagnetic opening / closing valve 4 that is opened and connects the outlet port 54 to the atmosphere is provided. In addition, the 0th inlet port is
It is closed without being connected to the crankcase. Further, as the light source of the photoelectric tube 55, the light emitting diode 5 which is intermittently turned on is used instead of the conventional tungsten lamp. Here, the reason why the light emitting diode 5 is turned on intermittently is that the oil mist concentration is continuous, so that, for example, the light emitting diode 5 is turned on every 0.1 to 0.2 seconds for measurement. This is because there is no problem in practical use, and by doing so, there is an advantage that the life of the light emitting diode 5 can be further extended and that the current can be increased and the light can be emitted with high brightness as compared with the case of continuous illumination.

FIG. 2 is a block diagram showing a control system of the alarm device. The alarm device includes a CPU (microcomputer) 6 as a control unit for controlling each block and a failure detection unit, and a port setting switch for setting the number of inlet ports actually connected to the crank chamber at knob positions 1 to 9. 7, a motor driver 8 for controlling the step motor 1, a detected mist concentration in a bar graph by blinking 16 light emitting diodes, and a mist indicator 9 for displaying a kind of failure at a lighting position when a failure is detected,
The output relays 10, 11 and 12 are lit to light the device, and the device has a failure, and the medium concentration mist (the level of the mist indicator).
11), equipped with alarm lamps 13, 14 and 15 for notifying high concentration mist (level 16 of mist indicator),
24V DC power is supplied through the fuse 16 and the power switch 17. The detection signal from the photocell 57 of the phototube 55 is supplied to the IC amplifier 19 with the gain adjusting knob 18.
Is amplified by the A / D converter 20, converted into a digital signal by the A / D converter 20, and input to the CPU 6. When the number of inlet ports to be connected to the crank chamber is set by the port setting switch 7, the first to the inlet ports corresponding to the set number are sequentially connected to each crank chamber in ascending order of chamber number. It

As the control unit, the CPU 6 receives the detection signal from the photo sensor 3 for detecting the origin of the rotation angle of the valve body 53 (the position of the 0th inlet port), and responds to the setting number of the port setting switch 7 from the 1st. The control of one rotation of the step motor 1 is started so that each inlet port position up to the turn position is stopped for a certain period of time and the other inlet ports are not stopped. Here, for each inlet port specified by the port setting switch 7, the time including feed and temporary stop is 1 second, and for each other inlet port that is fast-forwarded without stopping, the required time is Is about 0.2 seconds. Then, the photo sensor 3
When the detection signal from is not input for a predetermined time (20 seconds)
(See S2 to S4 in FIG. 4), the valve body 5 of the rotary valve 51.
Assuming that 3 is not rotating normally, the alarm lamp 13 for failure is turned on via the output relay 10 to issue an alarm, and the light emitting diode at the bottom of the mist indicator 9 is turned on as the first trouble (FIG. 4). See S5).

Further, the CPU 6 outputs the output signal (output signal at the time of non-mist, reference voltage) from the photocell 57 in the non-mist state obtained by the automatic zero adjustment described later and the valve body 53.
Of the output signal from the photocell 57 when it is stopped at the position of the inlet port leading to the crank chamber (output signal at the time of mist detection), this difference signal shows the medium mist concentration for 0.5 seconds or more. When the first threshold value represented is exceeded, the alarm lamp 14 for medium mist concentration is lit via the output relay 11 to issue an alarm, and the difference signal exceeds the second threshold value representing high mist concentration for 0.5 seconds or more. Then, the alarm lamp 15 for high mist concentration is turned on via the output relay 12 to issue an alarm, and the step motor 1 is immediately stopped at that position via the motor driver 8. In addition,
In FIG. 2, 21 is a test button for arbitrarily testing the operation of the alarm circuit, 22 is a reset button for returning the alarm device to the initial state when the alarm lamp 14 for high mist concentration is activated, and 23 is It is a blinking light that blinks during normal operation.

Further, since the CPU 6 causes a slight decrease in the photocell output due to contamination of the lens 61 due to mist, the automatic zero point adjustment is performed to eliminate the detection error due to this.
The procedure is as follows. That is, the CPU 6
Counts the detection signal from the photo sensor 3 emitted once for each rotation of the valve body 53, and at the beginning of the operation of the alarm device, each time the count value increases by 6, the valve is detected at the 0th port position. The body 53 is stopped, and the electromagnetic open / close valve 4 is excited for 4 seconds repeatedly 10 times. After that, the electromagnetic open / close valve 4 is excited for 4 seconds each time the count value increases by 50.
Atmosphere (fresh air) is caused to flow from the outlet port 54 into the photoelectric tube 55 by opening the electromagnetic opening / closing valve. Then, the detection signal of the photocell 57 when the fresh air is flown is used as the detection signal (reference voltage) in the non-mist state, and the difference signal between this reference voltage and the mist detection signal of each crank is the first and second signals. The zero point adjustment of the photocell output is automatically performed by determining whether or not an alarm is necessary depending on whether or not the threshold value is exceeded. Here, since the time interval for zero adjustment requires a maximum of 10 seconds for one rotation of the valve body,
The initial period of operation is approximately 1 minute, and the period of time after that is approximately 10 minutes. The reason for providing such a difference is that the temperature change of the semiconductor element included in the CPU or the like is large at the initial stage of operation and becomes small thereafter.

On the other hand, the CPU 6 serves as a failure detection unit, and the first lower limit value in which the output signal at the time of non-mist (see S8 in FIG. 4) from the photocell 57 corresponds to the permissible dirt of the lens 61 in the phototube due to the mist. When it becomes less than (for example, 1V), the alarm lamp 13 is output via the output relay 10.
Is turned on and the second light emitting diode from the bottom of the mist indicator 9 is turned on to indicate that a second trouble has occurred, and a warning of deterioration of the photocell performance is issued (S in FIG. 4).
9, S10). Further, the mist detection output signal from the photocell 57 has a second lower limit value (for example, a second lower limit value smaller than the output signal corresponding to the high mist concentration and the first lower limit value).
(0.3 V) or less, the alarm lamp 13 is turned on in the same manner as described above, and the third light emitting diode from the bottom of the mist indicator 9 is turned on to indicate that a third trouble has occurred, and a photocell failure alarm is issued. Is issued (S in Fig. 4
11, S12).

Further, the CPU 6 measures the output voltage of the B contact of the output relay 10 which outputs the supplied voltage as it is during demagnetization, and the measured value is lower than the lower limit voltage (for example, 12V) lower than the constant voltage 24V of the DC power supply. In the same manner, the alarm lamp 13 is similarly turned on, and the fourth light-emitting diode from the bottom of the mist indicator 9 is turned on to indicate that the fourth trouble has occurred, and a power supply voltage drop alarm is issued (see FIG. 4). (See S15 and S16). Also, IC amplifier 1
When the output signal from 9 becomes the third lower limit value (1.5 V, for example), which is smaller than the output signal corresponding to the high mist concentration, the alarm lamp 13 is similarly turned on, and
If a trouble has occurred, the fifth light-emitting diode from the bottom of the mist indicator 9 is turned on and an amplifier failure alarm is issued (see S13 and S14 in FIG. 4).

The operation of the oil mist alarm device having the above structure will be described below with reference to the flowchart of FIG. The operator determines the number of inlet ports connected to the crank chamber of the diesel engine among the first to ninth inlet ports P provided in the casing 52 of the rotary valve 51 (see FIG. 1) by the port setting switch 7 (see FIG. For example, 6 (corresponding to 6 crank chambers) is set by the knob (see 2). When the valve body 53 of the rotary valve reaches the 0th inlet port,
The photosensor 3 that detects this outputs a detection signal to the CPU 6, and the CPU 6 that has received this detection signal starts the processing of FIG. 3, which is the control of one rotation of the step motor 1, that is, the valve body 53.

That is, the CPU 6 executes step S1 of FIG.
Then, initialization is performed, and since it is already in the state of step S2,
In step S3, whether or not it is the zero adjustment time is determined by multiplying the count value of the detection signal from the photo sensor 3 by 6 (the count value is 6).
Whether it is 0 or less) or a multiple of 50 (count value is 6
(If it is 0 or more) When it is determined that it is the zero-point adjustment time, the process proceeds to steps S4 and S5, the electromagnetic on-off valve 4 is opened, and the 4-second timer starts counting. Then, fresh outside air flows into the photoelectric tube 55 through the outlet port 54 (see FIG. 1), and the photocell 57 outputs a detection signal in the non-mist state to the CPU 6. Therefore, CPU6
After the time of 4 seconds described above, the valve body 53 is located at the 0th inlet port, so it is determined to be affirmative in step S6, and step S6
At 7, the detection signal in the non-mist state is set as a reference voltage. Next, also in step S8, since the valve body is in the 0th port, it is determined to be affirmative, and the process proceeds to step S9.

In step S9, the CPU 6 closes the electromagnetic on-off valve 4, and in steps S10 and S11, rotates the step motor 1 to the first port by one port at the same time.
Starts the counting of the second timer. By the time it is determined in step S15 that the time measurement by the 1-second timer is completed, the valve body reaches port 1 in approximately 0.2 seconds, and the oil mist in the first crank chamber is stopped by the photoelectric tube during the 0.8 second pause. 55, the mist detection signal from the photocell 57 is read into the CPU 6 in step S12, and in step S13,
The difference between the reference voltage and the read detection signal is obtained, and in step S14, the mist indicator 9 is turned on to a level according to the difference signal. If it is determined in step S15 that one second has elapsed, the process returns to step S6.

At this time, since the valve body is at the 1st port,
In step S6, it is determined to be no, the process proceeds to step S16, it is determined whether or not the difference signal exceeds the first threshold value for 0.5 seconds or more, and if it is determined to be no, step S8,
After S9, in step S10, the valve body is further rotated by one port to the second port, and steps S12 and S13 are performed.
After that, in step S14, the mist concentration of the second crank chamber is displayed on the mist indicator 9. Thus, the sixth
Mist concentration up to the crank chamber is low (below the first threshold)
If the mist indicator 9 repeats the above path
The mist concentration of each crank chamber is displayed in a bar graph one after another, and when the valve body reaches the 7th port which is not connected to the crank chamber, it is determined to be no in step S8, and step S8 is performed.
Returning to step 2, the valve element is fast-forwarded to the 0th port in step S2 without stopping. And step S3
If it is determined that it is not the zero point adjustment timing, processing such as mist concentration display for ports 1 to 6 after step S8 described above is performed, and if it is determined that the zero point adjustment timing is reached, steps S4 to S7 described above are performed. The zero point adjustment process is performed again.

As described above, in the above embodiment, the step motor 1 controlled by the CPU 6 fast-forwards the valve body 53 for the inlet port not connected to the crank chamber, so that the time required for one rotation of the valve body is It is possible to drastically reduce the driving time by the conventional Geneva gear mechanism from 40 seconds to a maximum of 10 seconds, the blind time for mist detection is shortened, and the probability of finding a mist abnormality can be greatly improved. Further, the CPU 6 opens the electromagnetic open / close valve 4 at a predetermined time interval based on the detection signal of the photo sensor 3 at the 0th port position of the valve body, and automatically adjusts the output of the photo cell 57 to the zero point. Photocell 55 while saving the trouble of
It is possible to accurately detect the mist concentration and issue an accurate mist alarm as described later, regardless of the fog caused by the mist of the lens 61. In addition, the above predetermined time interval is set to the CPU
Since the alarm device such as 6 having a large temperature change of the semiconductor element is set small at the initial stage of operation and is set to be large after the characteristic of the semiconductor element is stable, the mist detection error due to the change with time of the semiconductor element can be eliminated. Further, the CPU 6 receives the detection signal of the photo sensor 3, that is, the valve body 53 is set to 0.
The control of one rotation of the valve body is started via the step motor 1 every time when it comes to the port # 2, and if the number of pulses generated by the step motor 1 matches the preset number of pulses according to the port position, Since it determines that the valve has reached that port, even if the stop position at each inlet port of the valve disc shifts, the positional shift is corrected for each rotation, which is combined with the warning of the rotary valve failure described above. Thus, the valve body can be accurately driven.

Next, in step S16 of FIG. 3, when it is determined that the difference signal between the reference voltage and the mist detection signal of each crank chamber exceeds the first threshold value for 0.5 seconds or more, the process proceeds to step 17. The photocell voltage, that is, the mist signal is read by the CPU 6, the difference signal is obtained in step S18, and the mist concentration corresponding to the difference signal is displayed in a bar graph on the mist indicator 9 in step S19, and the output relay The alarm lamp 14 for medium mist concentration is turned on via 11 to issue an alarm. If the difference signal does not exceed the second threshold value for 0.5 seconds or more, it is determined as NO in step S20, and the process returns to step S8, while the difference signal exceeds the second threshold value for 0.5 seconds or more. Proceeds to step S21. Step S21
Then, similarly to the above, the mist concentration corresponding to the difference signal is displayed in a bar graph on the mist indicator 9, and the alarm lamp 15 for high mist concentration is turned on via the output relay 12 to give an alarm and the step motor 1
The valve body 53 is immediately stopped via the. Therefore,
The operator can know the crank chamber number of the mist abnormality of high mist concentration from the stop position of the valve element. Finally, in step S22, the reset button 22 (see FIG. 2)
It is determined whether or not is pressed, and if it is determined that it is pressed, the process proceeds to step S23, the alarm lamps 15 and 14 are turned off via the output relays 12 and 11, and the CP
After initialization by U6, the process returns to step S2.

In the above-mentioned embodiment, the light emitting diode 5 which is intermittently turned on is used as the light source of the photoelectric tube 55, and the durability is superior to that of the conventional tungsten lamp, and the maximum amount of light can be obtained at the same time when the power is turned on. The number of false alarms is reduced. Further, since the CPU 6 stops the step motor 1 only when the difference signal exceeds the second threshold value for a certain period of time as described above, unnecessary motor stop is avoided and the oil mist alarm device operates. The rate is improved. Further, when the difference signal exceeds the first and second threshold values for a certain period of time, respectively, a mist alarm and a high mist concentration alarm (two-stage alarm) are issued, so that the mist alarm does not disappear instantaneously. There is an advantage that the high-concentration mist can be reliably detected without adverse effects such as noise, and a more accurate and detailed mist alarm can be issued. Further, in the above-mentioned embodiment, as can be seen from FIG. 2, the photoelectric tube 55, the step motor 1, the photo sensor 3, C
Since 24V DC power is supplied to the PU 6 and the electromagnetic on-off valve 4, unlike the conventional example in which an AC power supply of 100 to 200V is used, the power can be secured even during blackout, and it is suitable for a diesel engine of a ship. . Further, since the control system including the CPU 6 is formed as a printed circuit board and the valve body 53 is directly driven to rotate by the program control of the step motor 1 by the CPU 6, the valve body is driven to rotate intermittently via the AC motor and the Geneva gear mechanism. Compared with the conventional example, the alarm device can be simplified and made compact, the failure rate of the device can be reduced, and the reliability of the device can be greatly improved.

The failure detecting operation of the oil mist alarm device will be described below with reference to the flow chart of FIG. When the operation of the device is started, the CPU 6 detects the failure of the rotary valve in step S1 and subsequent steps, and executes step S7.
The following other fault detection processes are started. First, the CPU
In step S2, 6 determines whether or not there is a detection signal (H) from the photo sensor 3 which is the origin sensor of the valve body 53. If there is no detection signal (H), in step S3, the 20-second timer starts counting and 2
If there is a detection signal within 0 seconds, the process proceeds from step S2 to step S6 to clear the timer. On the other hand, 20
If there is no detection signal within the second, the process proceeds to step S5, it is determined that the valve body 53 is not rotating normally, the alarm lamp 13 for failure is turned on via the output relay 10, and the first trouble occurs. Then, the light emitting diode at the bottom of the mist indicator 9 is turned on to issue a rotary valve failure alarm. The operator disassembles the rotary valve 51 and the step motor 1 by this alarm,
The faulty part can be repaired. Next, CPU6
In step S8, it is determined whether or not it is time to automatically adjust the zero point of the photocell output of the photocell as described above. If it is determined that it is the automatic zero point adjustment time, fresh air is flowing in the photocell 55. In step S9, it is determined whether or not the output signal of the photocell 57 in the non-mist state is equal to or lower than the first lower limit value (1V). If it is determined that the value is equal to or lower than the lower limit value, the alarm lamp 13 is turned on via the output relay 10 in step S10. , The second light emitting diode from the bottom of the mist indicator 9 is turned on, and an alarm of deterioration of the performance of the phototube is issued. The operator
This alarm cleans the lens 61 in the phototube,
The light emitting diode 5 as a light source can be replaced.

On the other hand, if it is determined in step S8 that it is not the automatic zero point adjustment timing, it is time to measure the mist concentration, so the process proceeds to step S11, in which the mist detection output signal of the photocell 57 is the second lower limit value (0.3 V). Determine if the following,
If the following is determined, in step S12, similarly, the alarm lamp 13 and the third light emitting diode from the bottom of the mist indicator 9 are turned on to issue a photocell failure alarm. The operator is informed by this alarm that the photocell 57
Can be replaced. Second in step S11
If it is determined that the lower limit value is exceeded, there is no problem with the photocell, so the process proceeds to step S13, and it is determined whether the output signal of the IC amplifier 19 is the third lower limit value (1.5 V) or less. The alarm lamp 13 and the fifth light emitting diode from the bottom of the mist indicator 9 are turned on to issue an alarm of amplifier failure. The operator can replace the IC amplifier 19 by this alarm.
If the third lower limit value is exceeded in step S13, step S
15, the power supply voltage output to the B contact of the output relay 10 is measured, and it is determined whether or not the measured value is less than or equal to the lower limit voltage (12V). If less, in step S16, the alarm lamp 13 and the mist indicator The fourth light emitting diode from the bottom of 9 is turned on to issue a warning of a power supply voltage drop. The operator can check the states of the fuse 16 and the power switch 17 by this alarm.

As described above, in the above embodiment, in addition to the failure of the rotary valve 51 and the photocell 57 and the deterioration of the performance of the photoelectric tube 55, the failure information of the oil mist alarm device such as the decrease of the power supply voltage and the failure of the amplifier is clear. The operator will be informed immediately, and the faulty part requiring inspection and repair will be immediately known.
Since appropriate measures can be taken promptly, maintenance of the device becomes extremely easy, and the reliability of the device can be greatly improved.

[0028]

As is apparent from the above description, claim 1
The oil mist alarm device is a step motor that rotationally drives a valve element of a rotary valve that sequentially connects a predetermined number of inlet ports that can be connected to each crank chamber of the engine to an outlet port, and has a light source and a light receiving device at one end and the other end. A photoelectric tube having an element, in which the oil mist of each crank chamber is guided inside from the outlet port by a blower, an origin sensor for detecting the origin of the rotation angle of the valve disc, and a detection signal from the origin sensor during a predetermined time. If the rotary valve failure alarm is issued, the non-mist output signal, which is the output of the light receiving element when the inside of the photocell is in the non-mist state, and the valve body is stopped at the position of the inlet port leading to the crank chamber. When the difference signal from the output signal at the time of mist detection, which is the output of the light receiving element of, exceeds a predetermined value, stop the step motor at that position, and When the control unit that issues a strike alarm and the non-mist output signal falls below the first lower limit value that corresponds to the permissible dirt inside the phototube due to mist, the phototube performance degradation alarm is issued, while the mist detection output When the signal becomes equal to or less than the output signal corresponding to the high mist density and the second lower limit value smaller than the first lower limit value,
Since it is equipped with a failure detection unit that issues an alarm for a light-receiving element failure, the probability of finding a mist abnormality can be increased by shortening the cycle of one rotation as compared with the case of intermittent drive of the valve body via the Geneva gear mechanism. The operator can be informed of the mist abnormality and its crank chamber number, and the operator can accurately know the information about the deterioration of the photocell performance and the failure of the rotary valve and the light receiving element. It can be done quickly, the maintenance of the device is easy, and the reliability of the device is greatly improved.

In the oil mist alarm device according to a second aspect of the present invention, an amplifier is provided between the light receiving element and the control unit, the power is supplied from a DC power supply of a constant voltage, and the failure detection unit causes the voltage of the DC power supply to be the above-mentioned. When the voltage becomes lower than the lower limit voltage which is lower than a certain voltage, a power supply voltage drop alarm is issued, and when the output signal of the amplifier becomes the third lower limit value which is smaller than the output signal corresponding to the high mist concentration, Since the alarm of the amplifier failure is issued, the operator can know the information about the drop of the power supply voltage and the failure of the amplifier in addition to the above-mentioned failure information, so that the maintenance of the apparatus becomes easier and the apparatus can be maintained. Reliability is further improved.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of an oil mist alarm device of the present invention.

FIG. 2 is a block diagram showing a control system of the above embodiment.

FIG. 3 is a flowchart showing a flow of operations of the above embodiment.

FIG. 4 is a flowchart showing a flow of a failure detection operation of the above embodiment.

FIG. 5 is a configuration diagram showing a conventional oil mist alarm device.

[Explanation of symbols]

1 ... Step motor, 2 ... Rod, 3 ... Photo sensor,
4 ... Electromagnetic on-off valve, 5 ... Light emitting diode, 6 ... CPU, 7
… Port setting switch, 9… Mist indicator, 13
... alarm lamp for failure, 14 ... alarm lamp for medium mist concentration, 15 ... alarm lamp for high mist concentration, 51 ... rotary valve, 52 ... casing, 53 ...
Valve body, 54 ... Outlet port, 55 ... Phototube, 55a ... Inlet hole, 55b ... Outlet hole, 57 ... Photocell, 58 ... Blower, 61 ... Lens, P ... Inlet port.

Claims (2)

[Claims] 1. A rotary valve, which is provided in a casing and sequentially switches a predetermined number of inlet ports that can be connected to respective crank chambers of an engine to an outlet port of the casing through a passage in a valve body that is rotationally driven to communicate with the rotary valve. , A light source is provided at one end, a light receiving element is provided at the other end, an outlet port of the rotary valve is provided at an inlet hole, and a photoelectric tube to which a blower is connected is provided at the outlet hole. In an oil mist alarm device that detects the concentration of the above and issues an alarm, a step motor that rotationally drives the valve body of the rotary valve, an origin sensor that detects the origin of the rotation angle of the valve body, and a detection signal from the origin sensor. If it is not within a predetermined time, the rotary valve failure alarm is issued, while the output of the light receiving element when the inside of the phototube is in the non-mist state is output. When the difference signal between the output signal during mist detection and the output signal during mist detection, which is the output of the light receiving element when the valve disc is stopped at the position of the inlet port leading to the crank chamber, exceeds a specified value, When the step motor is stopped at that position and a mist alarm is issued, and when the non-mist output signal falls below the first lower limit value corresponding to the permissible dirt in the photo tube due to mist, the photo tube performance is degraded. While the mist detection output signal is below the output signal corresponding to the high mist concentration and the second lower limit value smaller than the first lower limit value, the light emitting element failure alarm is issued. An oil mist alarm device characterized by having a detection unit. 2. The oil mist alarm device according to claim 1, further comprising a direct-current power supply of a constant voltage for supplying electric power and an amplifier interposed between the light receiving element and the control unit, and the failure detection. The section issues a power supply voltage drop alarm when the voltage of the DC power supply becomes lower than the lower limit voltage lower than the constant voltage, and the output signal of the amplifier is smaller than the output signal corresponding to the high mist concentration. 3. An oil mist alarm device that issues an alarm for amplifier failure when it falls below the lower limit.