JPH0437260Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a fuel temperature adjustment device for internal combustion engine testing, and in particular, to a fuel temperature adjustment device for internal combustion engine testing that adjusts the fuel of a diesel engine to a temperature suitable for testing. This invention relates to a fuel temperature adjustment device.

[Conventional technology]

When performing an output test of a diesel engine, the engine output test cannot be performed in the optimum condition unless the fuel temperature is adjusted to a constant temperature. Adjustments have been made to the temperature of the fuel. That is, an electric heater is provided in a part of the fuel passage leading from the fuel tank to the fuel injection pump, and a heating/cooling means is used to selectively introduce engine cooling hot water and cold water from the cooling means depending on the temperature. The temperature of the fuel is adjusted accordingly.

[The problem that the idea aims to solve]

However, since conventional devices are configured to simply adjust the fuel temperature using heating/cooling means and an electric heater, it is difficult to accurately adjust the fuel temperature and test at a wide range of different fuel temperature settings. It was difficult.

In addition, although it is not a conventional fuel temperature adjustment device for internal combustion engine testing, it is an injection fuel supply device for an internal combustion engine that uses a cooler with cooling fluid such as cooling water or cold air for the internal combustion engine and controls the fuel temperature using a temperature sensor. (Utility Model Application Publication No. 57-157755) has been proposed.

However, this device is only equipped with a cooler (cooling device), and only controls whether or not the fuel passes through the cooler.

Therefore, like the above-mentioned apparatus, it is difficult to keep the fuel temperature at a constant temperature with high accuracy suitable for testing, and it is also difficult to test at fuel set temperatures that vary over a wide range.

The present invention was made in view of the above-mentioned conventional problems, and its purpose is to reduce control delay,
The fuel temperature is kept at a constant temperature with high precision suitable for testing, and the fuel temperature can be controlled over a wide range.
An object of the present invention is to provide a fuel temperature adjustment device for internal combustion engine testing that enables testing at a wide range of different fuel set temperatures.

[Means to solve the problem]

To achieve the above object, the present invention divides a part of the downstream side of the fuel passage from the fuel tank to the fuel injection pump into a cooling fuel passage and a heating fuel passage,
A heat exchanger for cooling the fuel is provided in the cooling fuel passage, a heat exchanger for heating the fuel is provided in the heating fuel passage, and the cooling heat exchanger uses water as a medium and is equipped with a first temperature detection means. installed in a low-temperature chamber,
The heat exchanger for heating is installed in a high-temperature bath using water as a medium and equipped with a second temperature detection means, and the temperature of each of the low-temperature bath and the high-temperature bath is determined based on the detection signals from the first and second temperature detection means. First and second controllers are provided to respectively control the cooling means and heating means provided therein, and valves are provided downstream of each heat exchanger in the cooling fuel passage and the heating fuel passage to adjust the amount of fuel passing through the heat exchanger. A third tube is installed in each fuel passage where the cooling fuel and the heating fuel join to detect the temperature of the fuel.
Furthermore, a fourth temperature detection means is provided in the overflow passage of the fuel injection pump and an overflow passage for return fuel, and the opening degree of each valve is determined by the detection output of the third and fourth temperature detection means. The present invention is characterized in that a control means is provided in a fuel passage leading from the fuel tank to the fuel injection pump.

[Effect]

The fuel supplied from the fuel tank to the fuel injection pump is divided into a cooling fuel passage and a heating fuel passage, and the fuel flowing through the cooling fuel passage is divided into a cooling fuel passage and a heating fuel passage. The fuel flowing through the heating fuel passage is controlled by a second controller based on the detection output of the second temperature detection means. It is heated by a heat exchanger which is heated via a heating means. The fuel that has passed through each heat exchanger flows in accordance with the opening degree of each valve under the control of the control means based on the detection outputs of the third temperature detection means and the fourth temperature detection means, and then merges to form the fuel. Supplied to the injection pump.

〔Example〕

Hereinafter, embodiments of the present invention will be described based on the drawings.

FIG. 1 shows the configuration of a preferred embodiment of the present invention. In the figure, a fuel injection pump (injection pump) 11 is connected to a fuel tank 10.
A valve 13 and a flow meter 1 are installed in the fuel passage 12 leading to the
4. A filter 15 is inserted, and a part of the downstream side of the fuel passage 12 is divided into a cooling fuel passage 12A and a heating fuel passage 12B, and each fuel passage 1
2A and 12B are combined again and connected to injection pump 11.

A cryostat 16 and a valve 17 are provided in the cooling fuel passage 12A. The cryostat 16 is filled with water, and heat exchangers 18 and 19 are disposed in the water to cool the fuel in the cooling fuel passage 12A, and a temperature sensor (a first temperature detection means) 20 is provided. Further, another heat exchanger 21 for cooling the water is arranged in the water.
This heat exchanger 21 includes a compressor 22, a condenser unit 23, a dryer 24, and a motor 25, and functions as a cooler unit (cooling means) 26. Also, the heat exchanger 21 includes a compressor 22.
The refrigerant compressed by
3. It is supplied via a dryer 24. Therefore, the water in the cryostat 16 is cooled by the heat exchanger 21, and the fuel in the cooling fuel passage 12A is further cooled by the cooled water through the heat exchangers 18 and 19. cooled down. Based on the detection output of the temperature sensor 20, the temperature of the water in the low temperature chamber 16 is adjusted by turning on and off the motor 25 in accordance with commands from the first controller 27.

On the other hand, in the heating fuel passage 12B, there is a high temperature tank 2.
8 and valve 29. The high temperature tank 28 is filled with water, and the heating fuel passage 1 is in this water.
A heat exchanger 30 for heating the fuel in 2B is provided, a heater 31 for heating the water, and a temperature sensor (second temperature detection means) 32 for detecting the temperature of the water. The water in the high temperature tank 28 is heated by a heater (heating means) 31,
The heat exchanger 30 is heated by the heated water,
Furthermore, the heating fuel passage 12 is connected via the heat exchanger 30.
The fuel in B is heated. Then, the heater 31 is turned on and off by a command from the second controller 33 based on the output of the temperature sensor 32.
By turning it off, the temperature of the water in the high temperature tank 28 is adjusted. Also valves 17, 2
9, the opening degree is controlled by a command from a computing unit 34 as a control means. Further, in this embodiment, the opening degrees of the valves 17 and 29 are adjusted so that the opening degrees are opposite to each other. That is, when the opening degree of the valve 17 increases, the opening degree of the valve 29 decreases. The opening degree of each valve 17, 29 is determined by a temperature sensor (third temperature detection means) 3 provided in the fuel passage 12C where the cooling fuel and heating fuel join.
The adjustment is made based on the detection output of No.5.

Further, in the fuel passage 12C where the cooling fuel and the heating fuel join, the injection pump 11 described above is installed.
There is a pump 11 with each injection nozzle 36, 3
7, 38, and 39 are connected. The excess fuel and the remaining fuel injected from each nozzle 36 to 39 are returned to the filter 15 from the injection pump 11 and each nozzle 36, 37, 38, 39 via an overflow passage 40. Overflow passage 4 returning to the filter 15
0 is provided with a temperature sensor (fourth temperature detection means) 41 that detects the temperature of the overflowing fuel, and the detection output of the temperature sensor 41 is sent to the computing unit 4.
2 is supplied. That is, in this embodiment, since the temperature of the fuel supplied to the injection pump 11 and the temperature of the fuel injected from each nozzle 36 to 39 are different, the overflow passage 4
The temperature of the fuel at zero is detected, and the opening degrees of the valves 17 and 29 are controlled based on this temperature.
Then, the detection output of the temperature sensor 41 and the detection output of the temperature sensor 35 are compared via calculation units 42 and 34, respectively, and when the detection output of each temperature sensor is different, the detection output of the temperature sensor 41 matches the set temperature. The opening degrees of the valves 17 and 29 are controlled accordingly. For example, when the temperature of the fuel is higher than the set temperature, the opening degree of valve 17 is increased, and the opening degree of valve 29 is increased.
Reduce the opening. Conversely, when the temperature of the fuel is low, the opening degree of valve 17 is decreased and the opening degree of valve 29 is increased.

As described above, in this embodiment, the fuel is cooled by the heat exchangers 18 and 19 and heated by the heat exchanger 30, and the opening degrees of the valves 17 and 29 are adjusted based on the detection output of the temperature sensor 41. Since the cooled fuel and the heated fuel are combined and fed to the injection pump 11, the fuel temperature changes depending on the load as shown by the characteristic 100, as shown in FIG. However, when temperature adjustment is not performed, the fuel temperature changes as shown in characteristic 101, but as shown in characteristic 102, it can be accurately maintained to approximate set temperature 103.

That is, the fuels are combined (mixed) downstream of the low temperature tank (cooling device) 16 and high temperature tank (heating device) 28 and just before the fuel injection pump 11, and while controlling the temperature at the mixing point, the final Since the fuel temperature is controlled based on the temperature of the temperature sensor (fourth temperature detection means) 41, the control delay is reduced.
The fuel temperature can be kept at a constant temperature with high accuracy suitable for testing.

Furthermore, in this embodiment, the controller 2
There is a dedicated low temperature tank (cooling device) 16 and high temperature tank (heating device) 28 that can be controlled by
By changing the fuel temperature setting using the computing unit 42, it becomes possible to control the fuel temperature over a wide range, and it becomes possible to perform tests at different fuel temperature settings over a wide range.

Note that the temperature sensor 41 is necessary when a distribution type injection pump is used, but when a row type injection pump is used as the injection pump, the injection pump is cooled with oil, so the temperature sensor 41 is unnecessary, and the detection output of the temperature sensor 35 is The temperature of the fuel can be maintained at the set temperature by adjusting the opening degrees of the valves 17 and 29 based on this.

[Effect of idea]

As explained above, according to the present invention, the control delay is reduced and the fuel temperature can be maintained at a constant temperature with high accuracy suitable for testing. Further, it has the remarkable effect of making it possible to control the fuel temperature over a wide range and making it possible to perform tests with different set fuel temperatures over a wide range.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram showing one embodiment of the present invention;
The figure is a diagram for explaining the temperature characteristics of the device according to the present invention. 10...Fuel tank, 11...Fuel injection pump (injection pump), 12, 12C...Fuel passage, 12A...Cooling fuel passage, 12B...
Heating fuel passage, 16...Cryogenic tank, 17, 29...
...Valve, 18, 19, 21, 30... Heat exchanger, 31... Heater, 20, 32, 35, 41...
...Temperature sensor, 26...Cooler unit, 27,
33...controller, 28...high temperature tank, 34,
42... Arithmetic unit, 40... Overflow path.

Claims (1)

[Scope of utility model registration request] A part of the downstream side of the fuel passage from the fuel tank to the fuel injection pump is divided into a cooling fuel passage and a heating fuel passage, and a heat exchanger for cooling the fuel is provided in the cooling fuel passage, and a heat exchanger is installed in the heating fuel passage. A heat exchanger for heating the fuel is provided, a heat exchanger for cooling the fuel is provided in a low temperature bath using water as a medium and is provided with a first temperature detection means, and a heat exchanger for heating the fuel is provided with a second temperature detection means. installed in a high-temperature tank with water as a medium,
First and second controllers are provided to control the cooling means and heating means provided in the low temperature chamber and the high temperature chamber, respectively, based on detection signals from the first and second temperature detection means, and cooling fuel is provided. A valve for adjusting the amount of fuel passing through the passage and the heating fuel passage is provided downstream of each heat exchanger, and a third temperature detection means for detecting the temperature of the fuel is provided in the fuel passage where the cooling fuel and the heating fuel join. Further, a fourth temperature detection means is provided in the overflow passage for the overflow and return fuel of the fuel injection pump, and a control means is provided for controlling the opening degree of each valve based on the detection output of the third and fourth temperature detection means. A fuel temperature adjustment device for internal combustion engine testing, characterized in that it is provided in a fuel passage leading from the fuel tank to the fuel injection pump.