JPH0422710A - Alarm device for clog of radiator - Google Patents

Abstract

PURPOSE:To enhance the maintenance performance for a radiator by judging the degree of radiator clogs corresponding to the revolution signal pattern for the engine concerned by reference to the specified judging criterion, and emitting in abnormal case a command signal for alarm issue to an alarm device. CONSTITUTION:A clog sensor 8 for sensing the degree of clogging of a radiator 4 is installed at the front of the radiator 4, while a revolution sensor 9 for sensing the engine revolving speed is mounted at the periphery of the engine 1, and the sensing signals from these sensors 8, 9 are fed to a controller 10. The revolution signal pattern for the engine 1 in case the radiator 4 is in normal operation and the judging criterion for radiator clogs are in advance stored in a memory (ROM) 11 of this controller 10. When the engine 1 is in operation, the controller 10 performs referencing to the revolution signal pattern for actual operations, judges the degree of clogging, and in case of abnormality, gives an appropriate command signal to an alarm device (buzzer, lamp, etc.).

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention This invention relates primarily to a clogging alarm system for a cooling water radiator of an engine installed in a construction machine 2 working vehicle.

BACKGROUND OF THE INVENTION FIG. 5 is a partially cutaway side view of a main part of a radiator device of a prior art. In the figure, 1 is the engine, 2 is the cooling fan provided in the engine 1, 3 is the drive shaft of the fan 2, 4 is the cooling water radiator of the engine 1, F
is the front side of the radiator 4, R is the rear side of the radiator 4, 5 is an oil cooler for cooling hydraulic oil, and 6 is a distribution oil pipe of the oil cooler 5. FIG. 6 is a plan view seen from A in FIG.

Next, the configuration of a conventional radiator device will be described with reference to FIGS. 5 and 6. A radiator 4 for cooling water of an engine 1 and an oil cooler 5 for cooling hydraulic oil are provided together, and the engine 1 equipped with a fan 2 is arranged on the rear side (R side) of the radiator 4. Air from the outside is allowed to pass through ventilation paths (not shown) of the oil cooler 5 and radiator 4.

Next, the functions of the radiator device will be described. Cooling water for the engine 1 whose temperature has increased passes through the radiator 4 , and returning hydraulic oil whose temperature has risen passes through the oil cooler 5 through the distribution pipe 5 . On the other hand, since the fan 2 rotates as the engine 1 rotates, air from the outside flows in the direction of arrow A, exchanging heat while passing through the radiator 4 and oil cooler 5, cooling the engine cooling water and hydraulic oil. do.

Problems to be Solved by the Invention Among construction machines, hydraulic excavators (not shown) are sometimes engaged in work that generates a large amount of dust around the excavator, such as demolition work of structures such as houses and buildings. In that case,
Since the cooling air sucked in from the outside passes through the radiator ventilation passage accompanied by dust, the ventilation passage becomes clogged with dust. As a result, the cooling function of the radiator deteriorated, resulting in insufficient cooling of the engine and hydraulic oil, often resulting in overheating.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and provide a clogging alarm device for a radiator that can issue an alarm or an alarm display when a radiator becomes clogged.

Means for Solving the Problems The means of the present invention taken to solve the above problems are as follows: (1) A clogging sensor for detecting the degree of clogging of the radiator is provided on the front side of the radiator, and A rotation sensor for detecting the engine rotation speed is provided around the area, and the detection signals from the above-mentioned clogging sensor and the rotation sensor are input to the controller.(b) On the other hand, the engine rotation signal pattern when the radiator is normal is shown in the controller. , the judgment of radiator clogging is entered in advance, and c. When the engine is rotating, the controller compares it with the rotation signal pattern during actual operation to determine the degree of radiator clogging, and if there is an abnormality, The controller was configured to output a command signal to the alarm.

(2) A. The radiator is equipped with a pitot tube that can measure atmospheric pressure, and the opening of the pitot tube is positioned facing the front side of the radiator. B. On the other hand, the pitot tube corresponds to the engine rotation speed when the radiator is normal. Set the standard for the displayed value of the tube, and then compare the actual displayed value with the above standard by visually checking the displayed value displayed on the pitot tube when the engine is rotated to the specified rotation speed. It is structured so that it can be judged based on the

(3) A. The radiator is equipped with a differential pressure switch that is activated by the difference in atmospheric pressure before and after the radiator, so that when the radiator becomes clogged, the differential pressure switch will activate and an alarm will issue an alarm. It was configured as follows.

Function (1) A. When the engine is operating, detection signals from the rotation sensor and the clogging sensor are input to the controller.

The controller makes a judgment based on the above detection signal,
If the degree of clogging of the radiator corresponding to the engine rotation signal pattern is normal when compared with the determination criteria, a command signal for generating an alarm is not output to the alarm device. In this case, therefore, no warning of clogging of the radiator is issued.

C. In the case of item A above, the controller determines that the degree of clogging of the radiator corresponding to the engine rotation signal pattern is abnormal when compared with the judgment criteria, and sends a command to the alarm to generate an alarm. is output. In this case, a warning of clogging of the radiator is thereby issued.

(2) A. When the engine is operating, the suction pressure at the front of the radiator is displayed on the pitot tube.

In paragraph 0.124, the engine is rotated to a predetermined rotation speed, for example, the maximum rotation speed, and the displayed value displayed on the pitot tube at that time is read. Thereby, its actual display value and
It is possible to determine whether the degree of clogging of the radiator is normal or abnormal by comparing the display value with a preset standard.

(3) A. If the degree of clogging of the radiator is normal when the engine is running, the differential pressure switch will not operate. Therefore, no warning of clogging of the radiator is issued.

When the radiator becomes clogged, the differential pressure across the radiator reaches a predetermined differential pressure, and the differential pressure switch is activated. Since the electrical circuit of the differential pressure switch is energized,
The alarm system issues an alarm to alert the driver that the radiator is clogged.

Embodiments Hereinafter, embodiments of the present invention will be described in detail based on the drawings. FIG. 1 is a circuit diagram showing a clogging alarm device 7 according to claim 1 of the present invention.

In the figure, the same reference numerals are given to the same components as in the prior art.

Next, the configuration of the clogging alarm device 7 according to claim 1 of the present invention will be described with reference to FIG. A clogging sensor 8 for detecting the degree of clogging of the radiator 4 is provided on the front side (F side) of the radiator 4, and a rotation sensor 9 for detecting the engine rotation speed is provided around the engine 1. Each detection signal from the rotation sensor 9 is input to the controller 10. On the other hand, the memo (ROM) 11 of the controller 10 contains the rotation signal pattern of the engine 1 when the radiator 4 is normal, and the rotation signal pattern of the engine 1 when the radiator 4 is normal.
The clogging criteria for the radiator 4 is input in advance, and when the engine 1 is rotating, the controller 1 determines the degree of clogging in the radiator 4 by comparing it with the rotation signal pattern during actual operation, and if an abnormality occurs, the controller 1. The controller 10 is configured to output a command signal to the alarm device (buzzer, lamp, etc.) 12.

Next, the functions of the clogging alarm device 7 according to claim 1 of the present invention will be described. When the engine 1 is in operation, detection signals from the rotation sensor 9 and the clogging sensor 8 are input to the controller 1o. The controller 10 makes a judgment based on the detection signal, and if the degree of clogging of the radiator 4 corresponding to the rotational signal pattern of the engine 1 is normal after checking with the determination criteria, it issues a command to the alarm device 12 to generate an alarm. No signal is output. Therefore, in this case, no warning of clogging of the radiator 4 is issued. However, the radiator 4 corresponding to the rotation signal pattern of the engine 1
If the degree of clogging is abnormal compared to the criteria,
A command signal for generating an alarm is output to the alarm device 12.

Therefore, in this case, a warning of clogging of the radiator 4 is issued. Note that the clogging sensor 8 is connected to the radiator 4.
Although it is provided immediately in front of the oil cooler 5, it may also be provided in front of the oil cooler 5. Further, the rotation sensor 9 may be arranged with respect to the drive shaft 3 to detect the rotation speed of the fan 2. Further, the controller 10 may be provided with a switch (not shown), and when the radiator 4 becomes clogged when the switch is operated, the alarm 12 may issue an alarm.

FIG. 2 is a side view of a main part of the clogging alarm device 13 according to claim 2 of the present invention. In the figure, the same reference numerals are given to the same components as in the prior art. 14 is a pitot tube, and L is a display value displayed on the pitot tube 14 when the engine 1 is operating. FIG. 3 is a chart showing the relationship between the rotational speed of the engine 1 and the displayed value of the pitot tube 14. In the diagram, curve a is a reference curve when the radiator 4 is normal, and curve a is an example curve when the radiator 4 is clogged.

Next, the configuration of the clogging alarm device 13 according to claim 2 of the present invention will be described with reference to FIGS. 2 and 3. The radiator 4 is provided with a pitot tube 14 that can measure atmospheric pressure, and the opening 16 of the pitot tube 14 is positioned facing the front side of the radiator 4, while the pitot tube corresponds to the engine rotation speed when the radiator 4 is normal. When the standard for the displayed value (L) (shown by curve a in FIG. 3) is set and the engine 1 is rotated to a predetermined rotation speed, the pitot tube 14
By visually observing the displayed value (L) displayed on the screen, the actual displayed value can be compared with the above-mentioned standard to make a judgment.

Next, the functions of the clogging alarm device 13 according to claim 2 of the present invention will be described. When the engine 1 is operating, the suction pressure on the front side of the radiator 4 is displayed on the pitot tube 14. Then, the engine is rotated to a predetermined rotation speed, for example, the maximum rotation speed, and the displayed value displayed on the pitot tube 14 at that time is read. Thereby, it is possible to determine whether the degree of clogging of the radiator 4 is normal or abnormal by comparing the actual display value with a preset display value reference.

FIG. 4 is a circuit diagram showing the configuration of a clogging alarm device 17 according to claim 3 of the present invention. In the figure, the same reference numerals are given to the same components as in the prior art. 18 is a differential pressure switch, 19.20 is a pressure intake port of the differential pressure switch 18 arranged on the front side and rear side of the radiator 4, respectively, 21.22 is an air pipe, 23 is an electric circuit, 24 is an alarm lamp, 25 is a power source.

Next, the configuration of the clogging alarm device 17 according to claim 3 of the present invention will be described with reference to FIG. to radiator 4,
A differential pressure switch 18 is provided which is activated by the differential pressure between the atmosphere before and after the radiator 4. When the radiator 4 becomes clogged, the activation of the differential pressure switch 18 activates an alarm, such as an alarm buzzer or lamp. In FIG. 4, a lamp 24 is provided) to issue an alarm.

Next, the functions of the clogging alarm device 17 according to claim 3 of the present invention will be described. If the degree of clogging in the radiator 4 is normal when the engine 1 is operating, the differential pressure switch 18 will not operate. Therefore, no warning regarding clogging of the radiator 4 is issued. However, when the radiator 4 becomes clogged, the differential pressure across the radiator 4 reaches a predetermined differential pressure, so the differential pressure switch 18 is activated.

Since the electrical circuit 23 of the differential pressure switch 18 is energized, the lamp 24 lights up, making the driver aware that the radiator 4 is clogged.

Effects of the Invention In the clogging alarm device according to the present invention, a clogging sensor, a pitot tube, a differential pressure switch, etc. are attached to the radiator,
If the radiator becomes clogged, a buzzer will sound.
It is now possible to issue a warning using a lamp or display an indication that the device is clogged. As a result, when the driver is driving a construction machine or work vehicle, he or she can recognize whether the radiator is normal or clogged.

Therefore, in the construction machine 1 work vehicle equipped with the radiator clogging alarm device according to the present invention, overheating of the engine and hydraulic oil can be prevented, and the maintainability of the radiator is improved.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing a clogging alarm device according to claim 1 of the present invention, and FIG. 2 is a circuit diagram showing a clogging alarm device according to claim 2 of the present invention.
3 is a diagram showing the relationship between the engine rotation speed and the displayed value of the pitot tube; and FIG. FIG. 5 is a circuit diagram showing the configuration of the alarm device, and FIG. 5 is a partially cutaway side view of the main part showing a conventional radiator device, and a top view as seen from above. 6 1 Engine 2 Fan 4 Radiator 5 Oil cooler 7.13. 17------Clogging alarm device 8------
--------- One clogging sensor 9 ------ One rotation sensor 10 Controller 11 Memory 12 --- Alarm 14 Pitot tube 18 --- One differential pressure Switch 23 The electrical circuit in Figure 6 is as shown in Figure 5.

Claims (3)

[Claims] (1) In a forced draft radiator system for construction machinery and work vehicles that is equipped with a cooling water radiator for a water-cooled engine and an oil cooler for hydraulic oil, there is an eye on the front side of the radiator to detect the degree of clogging of the radiator. A clogging sensor is provided, and a rotation sensor for detecting the engine rotation speed is provided around the engine, and detection signals from the clogging sensor and the rotation sensor are input to the controller.On the other hand, if the radiator is normal in the controller, The engine rotation signal pattern and the criteria for determining whether the radiator is clogged are entered in advance, and when the engine is running, the controller compares it with the rotation signal pattern during actual operation to determine the degree of radiator clogging. A clogging alarm device for a radiator, characterized in that, in the event of an abnormality, a controller outputs a command signal to an alarm. (2) In forced draft radiator systems for construction machinery and work vehicles that are equipped with a cooling water radiator for a water-cooled engine and an oil cooler for hydraulic oil, the radiator is equipped with a pitot tube that can measure atmospheric pressure. Position the opening so that it faces the front side of the radiator, and set the standard for the displayed value of the pitot tube that corresponds to the engine speed when the radiator is normal, so that when the engine is rotated to the specified speed, the pitot tube will 1. A clogging alarm device for a radiator, characterized in that it is configured so that a judgment can be made by visually observing the displayed value displayed on the tube and comparing the actual displayed value with the above-mentioned standard. (3) In forced draft radiator systems for construction machinery and work vehicles that are equipped with a cooling water radiator for a water-cooled engine and an oil cooler for hydraulic oil, the radiator is operated by a differential pressure in the atmosphere before and after the radiator. 1. A clogging alarm device for a radiator, comprising a switch so that when the radiator becomes clogged, the differential pressure switch is activated to cause an alarm to issue an alarm.