JPH0315797Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a control device for cooling operation time when an internal combustion engine is stopped.

[Conventional technology]

When an internal combustion engine is operated automatically, warm-up operation (when starting) and cooling operation (when stopping) are usually performed for a predetermined period of time for reasons of durability, except for emergency generators and the like.

By the way, the conventional way of determining the cooling operation time during stop operation is to lower the engine speed from the rated speed and rated load to low idling, regardless of the state of the internal combustion engine, and even if the engine stops with no load, there is a problem with durability. There are two methods: one is to determine the cooling operation time under the condition that there is no cooling operation, and the other is to detect the oil temperature and exhaust gas temperature of the internal combustion engine when the engine is stopped and determine the length of the cooling operation time based on these detected values.

[The problem that the idea aims to solve]

Of the conventional methods of determining the cooling operation time mentioned above, the former method does not cause any problem with the fixed operation time when the engine starts to stop from the state of rated rotation and rated load. Internal water temperature of
When operating with low oil temperature, cooling operation for a certain period of time determined by the rated rotation and rated load as described above is wasteful from an energy saving perspective, and even if a stop signal is issued, the cooling operation continues for a certain period of time as usual. Drivers were irritated by the fact that they had to wait until they stopped.

In the latter case, conversely, if the oil temperature or exhaust temperature of the internal combustion engine is low during stop operation, the cooling operation time is set short according to the above temperature even if the rotation speed and horsepower are high at this time. This causes problems due to high rotational speed or high horsepower when stopped.

In other words, in the case of an internal combustion engine, even if the oil temperature and exhaust temperature are low, if the engine is operated at a high rotational speed and is stopped after a short cooling period, the lubricating parts will run out of oil film and the lubrication will be damaged, such as seizure. It may cause defects. This also applies to large horsepower.

The present invention was developed with the above in mind, and its purpose is to measure water temperature, oil temperature, or other elements having substitute characteristics thereof, such as fuel consumption, during stop operation, and to calculate this by measuring horsepower and cooling operation. By determining the cooling operation time by correcting the relationship between time and the relationship between rotation speed and horsepower, optimal cooling can be achieved depending on the internal combustion engine's cooling water and oil temperature, exhaust temperature, as well as rotation speed and horsepower during stop operation. An object of the present invention is to provide a cooling operation control device for an internal combustion engine that can determine the operating time.

[Means and actions to solve the problem]

The present invention includes a detection part A that detects water temperature, oil temperature, or an element having substitute characteristics thereof, and a relationship between water temperature, oil temperature, or an element having substitute characteristics thereof, horsepower/cooling operation time, rotation speed, and horsepower. and an arithmetic circuit 6 that compares the output signal from the detection section A with the output signal from the storage circuit 5 to determine and output the cooling operation time when the internal combustion engine is stopped. The sensor measures water temperature, oil temperature, or other elements with substitute characteristics, such as fuel consumption, at the detection unit, and uses this information to determine the relationship between horsepower and cooling operation time, as well as the rotational speed and horsepower. The cooling operation time is determined by correcting the relationship.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings. 1 is a rotation sensor, 2 is a fuel flow meter, and these constitute a detection section A. 3 and 4 are waveform shaping circuits, 5 is a storage circuit, and 6 is an arithmetic circuit.

The relationship between fuel consumption, water temperature, oil temperature, horsepower, and cooling operation time is as shown in Figure 2. As fuel consumption increases, water and oil temperatures also rise, horsepower increases, and cooling operation time increases. Also, Figure 3 shows the horsepower (torque) performance curve of the internal combustion engine performance curve, and each curve in this figure shows the case when the fuel control lever (not shown) is changed in various ways. If the load changes with the fuel control lever set to the full position, the rotational speed will change along the outermost curve, and by sequentially setting the fuel control lever inward from the full position, each The rotational speed changes along each curve as the load changes in the state.

As can be seen from this horsepower performance curve, even if the rotational speed is high, the required horsepower is small under no-load conditions, and therefore the temperature of the cooling water and the lubricating oil are not high.

Therefore, if the cooling operation time is determined only by the above temperature, even if the temperature is low as mentioned above, if the rotation speed is extremely high and the cooling operation time is stopped for a short time, the rotating parts may seize. Problems may occur.

Therefore, horsepower is low (fuel consumption is low)
Also, if the rotation is high, a method must be adopted to lengthen the cooling operation time.

The relationships shown in FIGS. 2 and 3 are stored (programmed) in the memory circuit 5.

The rotation signal (pulse) from the rotation sensor 1 is then waveform-shaped by the waveform shaping circuit 3 and then processed by the arithmetic circuit 6.
It counts the pulses entering the motor and calculates the number of rotations. Similarly, the pulses from the fuel flow meter 2 are shaped into waveforms, and then the arithmetic circuit 6 calculates the amount of fuel consumed per unit time.

When the arithmetic circuit 6 operates to stop, the memory circuit 5
The relationship between fuel consumption, water temperature, oil temperature, and horsepower cooling operation time (see Figure 2), the relationship between rotation and horsepower (see Figure 3), and the measured rotation speed and fuel consumption stored in The cooling operation time is determined by comparing and calculating the amount, and the signal T thereof is outputted from the calculation circuit 6.

Note that the relationships between fuel consumption, water temperature, oil temperature and horsepower, cooling operation time, and rotation and horsepower vary slightly depending on the type and size of the internal combustion engine, so they must be changed depending on the type and size. .

In this way, in the past, the cooling time during stop operation was determined under the conditions of rated rotation and rated load, and the cooling time was constant regardless of the condition, but fuel consumption, which is a substitute characteristic for water temperature and oil temperature, By measuring this and correcting it based on the relationship between horsepower and cooling operation time and the relationship between rotation speed and horsepower during stop operation, the cooling operation time during stop operation is determined according to the operating condition of the internal combustion engine, and the cooling operation time during stop operation is determined. In the case of low load, the cooling operation time can be significantly shortened, resulting in energy-saving effects and a stop signal being issued and stopping in a relatively short time, giving the driver a sense of security when stopping. become. In addition, even when the cooling water temperature and oil temperature are low under high rotation and high horsepower conditions, the optimal cooling operation time that does not cause oil film depletion etc. is automatically set, and the durability of the lubricated parts is not adversely affected.

This invention can be used not only for automatic operation, but also for manually operated machines (industrial machinery, construction machinery, etc.) that are constantly operated by the driver, by displaying the cooling operation time and notifying the end of the operation with a buzzer etc. It is.

By shortening the cooling operation (warming-up operation) time in this manner, it becomes possible to achieve an energy saving effect and a sense of security for the driver when stopping the vehicle by issuing a stop signal and stopping the vehicle in a relatively short time.

[Effect of idea]

Since the present invention is as described above, water temperature, oil temperature, or an element having a substitute characteristic thereof, such as fuel consumption, is measured, and this is corrected based on the relationship between horsepower and cooling operation time and the relationship between rotation speed and horsepower during stop operation. By doing so, the cooling operation time during the stop operation can be determined according to the operating state of the internal combustion engine.

For this reason, during stop operation, the rated rotation and
The fixed cooling operation time, which was determined by the rated load, changes depending on the engine condition. At low rotation speeds and low loads, the cooling operation time can be significantly shortened, and at high rotation speeds and high horsepower conditions, the cooling water temperature and oil temperature can be reduced. Even when the temperature is low, the cooling operation time can be automatically set long enough to prevent the oil film from running out, and the durability of the lubricated parts will not be adversely affected.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of the configuration of an embodiment of the present invention, Fig. 2 is a diagram showing the relationship between fuel consumption, water temperature, oil temperature and horsepower/cooling operation time, and Fig. 3 is a diagram showing the relationship between horsepower and rotation. . 5 is a memory circuit, and 6 is an arithmetic circuit.

Claims (1)

[Scope of utility model registration request] A detection part A that detects water temperature, oil temperature, or an element having substitute characteristics thereof, a relationship between water temperature, oil temperature, or an element having substitute characteristics thereof, horsepower and cooling operation time, and a relationship between rotation speed and horsepower. The present invention is equipped with a memory circuit 5 that stores the information, and an arithmetic circuit 6 that compares the output signal from the detection unit A with the output signal from the memory circuit 5 to determine and output the cooling operation time when the internal combustion engine is stopped. This is a cooling operation control device for internal combustion engines.