JP4241269B2 - Engine test equipment - Google Patents

Description

  The present invention relates to an engine test apparatus for connecting an engine to an absorption motor and testing characteristics of the connected engine.

For example, when conducting an engine characteristic test such as a gasoline engine for automobiles, an absorption motor is connected to the output shaft of the engine on the bench, rather than running an automobile equipped with the engine and testing the engine characteristics. The characteristics of the engine are tested by simulating load changes such as various road surfaces, slopes, and wind pressure with the absorption motor (see Patent Documents 1 and 2).
Japanese Patent Laid-Open No. 3-9238 Japanese Patent Laid-Open No. 3-84432

  When trying to precisely test the characteristics of the engine, it is not sufficient to accurately simulate only the engine load, and the engine temperature change, the degree of cooling, etc. need to be reproduced in the same state as the actual scene.

FIG. 4 is a schematic diagram of a conventional engine test apparatus in consideration of engine cooling.

  An absorption motor 22 is connected to the engine 10 via a propeller shaft 21. The absorption motor 22 operates as a dynamo that generates power with the power from the engine 10 under the control of the load control unit 23, and acts as a load on the engine 10, or receives power from the outside to generate power to generate the engine. By operating as a motor that transmits power toward the vehicle 10, for example, it is possible to simulate a downhill or braked state, and with this absorption motor, the engine is mounted on an actual automobile and travels Various load changes can be simulated.

  Further, the engine 10 operates by receiving an amount of fuel supplied according to the control of the slot control unit 24.

  In this way, various characteristics of the engine 10 can be measured by operating the engine 10 and the absorption motor 22 while being controlled by the slot control unit 24 and the load control unit 23, respectively.

  A water pump 11 is arranged inside the engine 10, and the water pump 11 sends out cooling water for cooling the engine 10 toward the radiator 25, and again passes through the radiator 25 and passes through the engine 10 again. A circulation path 26 is formed so as to return to FIG.

  A fan 27 is provided in front of the radiator 25, and wind is sent to the radiator 25 by the fan 27. This wind simulates the wind that hits the radiator 25 when the vehicle is running.

In the case of the configuration shown in FIG. 4 , the cooling system for the engine 10 is equivalent to the cooling system for driving an actual vehicle, and as long as the fan 27 has a sufficient air volume, the cooling of the engine 10 is also performed for the actual vehicle. Simulates the equivalent of running.

However, the problem with the engine test apparatus of FIG. 4 is that the cooling during high-speed running cannot be simulated. In the case of the fan 27 having a reasonable range (dimensions, price, etc.) for constituting the engine test apparatus, the fan 27 can generate a wind having an air volume that can simulate a wind of about 100 km / h at most. However, it is not possible to accurately simulate engine cooling at high speeds beyond that. In recent years, driving performance of the car also improve more, experiment on is it is required to simulate the high speed of about 200 km / h, which a large amount of it to the high speed of the wind to achieve the engine testing apparatus of FIG. 4 It is not realistic to prepare a large wind tunnel to be generated.

FIG. 5 is a schematic diagram of an engine test apparatus equipped with another conventional engine cooling system.

The same components as those of the engine testing apparatus of FIG. 4, denoted by the same reference numerals as those in FIG. 4, only will be described differences from the engine testing apparatus of FIG.

In the case of the engine test apparatus of FIG. 5 , a temperature control device 28 is provided at the tip of the cooling water circulation path 26.

  This temperature control device 28 once takes in the cooling water sent from the engine 10 via the forward path 26A by the water pump 11 and adjusts the temperature of the taken cooling water, and then the temperature is adjusted. The cooling water is configured to be sent to the engine 10 via the return path 26B.

  The temperature adjustment of the cooling water by the temperature control device 28 (for example, cooling. In some cases, it may be necessary to warm the cooling water, but here the cooling will be described), the capability is to be sufficient. Thus, with regard to the cooling capacity of the cooling water, it is possible to simulate a considerably high speed driving state such as 200 km / h during actual vehicle driving.

  However, it is not only the temperature of the cooling water that affects the cooling of the engine 10, but in order to accurately simulate actual vehicle travel, the flow rate and pressure of the coolant are equivalent to those during actual vehicle travel. There is a need to.

  However, since the temperature control device 28 temporarily stores the cooling water sent from the engine 10 and cools it to an appropriate temperature and then sends it to the engine 10, the temperature control device 28 is directed from the engine 10 to the temperature control device 28. When the flow rate and pressure of the cooling water in the forward path 26A and the flow rate and pressure of the cooling water in the return path 26B sent from the temperature control device 28 toward the engine 10 are not particularly controlled, They are not necessarily the same as each other, and as they are, it is impossible to realize a state equivalent to that during actual vehicle travel.

In the engine test apparatus of FIG. 5 , if an attempt is made to achieve a state equivalent to that during actual vehicle travel, including not only the temperature of the cooling water but also the flow rate and pressure of the cooling water, the temperature of the cooling water is set inside the temperature control device 28. In addition to incorporating equipment that can adjust not only the flow rate and pressure, but also the flow rate and pressure of cooling water in the forward path 26A that is sent from the engine 10 to the temperature adjustment device 28, and the temperature adjustment device 28 to the engine. It is necessary to control so that the flow rate and pressure of the cooling water in the return path 26B sent to 10 are the same flow rate and pressure, and a temperature control device having such equipment is prepared. is extremely difficult to the same extent as providing a wind tunnel in the engine testing apparatus of FIG. 4, there is a problem of poor feasibility.

For this reason, conventionally, when simulating high-speed running, for example, an engine test device similar to that shown in FIG. 5 , the temperature control device 28 is responsible only for cooling water temperature adjustment, and the flow rate and pressure are the same as those during actual high-speed running Is aware of the fact that there is a large error, the method of testing the characteristics of the engine and estimating the characteristics at the actual high-speed driving has been adopted, it is possible to realize a test that simulates high-speed driving with high accuracy I was waiting.

Incidentally, in the case of the engine test apparatus of FIG. 4 , the radiator 25 simply passes the cooling water and returns to the engine 10, so if the amount of pressure drop in the radiator 25 is ignored, the flow rate of the cooling water or The pressure is the same in the forward path 26A and the return path 26B of the circulation path 26, and the pressure drop in the radiator 25 is the same as the pressure drop in the actual automobile cooling system, and therefore the flow rate of the cooling water There is no pressure problem.

  In view of the above circumstances, an object of the present invention is to provide an engine test apparatus capable of performing a test that simulates high-speed traveling with high accuracy.

The engine test apparatus of the present invention that achieves the above object is an engine test apparatus for connecting an engine to an absorption motor and testing the characteristics of the engine.
A temperature controller for adjusting the temperature of the heat medium;
And a heat exchanger that exchanges heat between the heat medium whose temperature is adjusted by the temperature controller and the cooling water for cooling the engine.

Since the engine test apparatus of the present invention includes the heat exchanger described above, the cooling water sent out from the engine simply passes through the heat exchanger and returns to the engine. regarding and pressure, as in the conventional example of FIG. 4, dominate the water pump 11 of the engine 10 shown in FIG. 4, separately prepared to facility the flow rate and pressure is required. Further, in the case of the engine testing apparatus of the present invention comprises a temperature controller for adjusting the temperature of the heat medium for heat exchange with the cooling water in the heat exchanger, the temperature controller, the conventional 5 Unlike the case of the temperature control device 28 in the example, a facility for controlling the flow rate and pressure with high accuracy is not particularly required, and the temperature controller may be a facility dedicated to the adjustment of the temperature of the heat medium, for example, 200 km / Temperature adjustment at a level simulating actual high-speed traveling of about h can be easily performed.

Here, the engine test apparatus of the present invention is
A radiator for passing cooling water,
With a fan that hits the radiator,
The cooling water sent from the engine is returned to the engine via both the radiator and the heat exchanger, and the first cooling water circulation path for returning the cooling water to the engine via only the radiator of the radiator and the heat exchanger. a circulation path switching valve for switching between the second cooling water circulation passage includes further.

For example, when simulating traveling at a low speed of 100 km / h or less, the engine test apparatus including the radiator 25 and the fan 27 shown in FIG. 4 is very close to the structure of an actual automobile, and the cooling of the engine is extremely high accuracy. Can be simulated. Thus, as described above, further comprising a radiator and a fan, when configured to be able to switch the cooling water circulation passage, when the test simulating a slow running precision of the cooling system and the same cooling system shown in FIG. 4 4 and simulating high-speed running that cannot be handled by the cooling system of FIG. 4 , while using a radiator and a fan, the temperature controller and the heat exchanger are supplementarily operated only by the amount that is not sufficient. Even during traveling, it is possible to configure a cooling system with higher accuracy than that of a cooling system that uses only a temperature controller and a heat exchanger (not using a radiator and a fan).

Here, the engine testing apparatus of the present invention includes the radiator and the fan further includes a circulation path switching control unit for switching the circulating path switching valve according to the rotational speed of the engine.

    As described above, according to the present invention, high-speed running can be simulated with high accuracy in regard to engine cooling.

  Hereinafter, embodiments of the present invention will be described.

  FIG. 1 is a block diagram showing a first embodiment of an engine test apparatus of the present invention.

The same components as those of the conventional example of FIGS. 4 and 5 described above are denoted by the same reference numerals as those shown in FIGS. 4 and 5 , and only the differences will be described.

  The cooling water delivered from the water pump 11 of the engine 10 reaches the heat exchanger 30 via the forward path 26A, returns to the engine 10 via the interior of the heat exchanger 30, and further via the return path 26B. Therefore, the flow rate and pressure of the cooling water passing through the circulation path 26 are governed by the water pump 11. Therefore, in the case of the engine test apparatus of FIG. 1, the flow rate and pressure of the cooling water can reproduce the same state as during actual traveling.

  Further, the temperature controller 31 plays a role of adjusting a heat medium (for example, water equivalent to cooling water or a refrigerant such as chlorofluorocarbon) to a desired temperature, and the heat medium sent from the temperature controller 31. Enters the heat exchanger 30 through the forward path 38A of the heat medium circulation path 38, exchanges heat with the cooling water sent from the engine 10 to the heat exchanger 30, and the heat medium circulation path 38 The return path 38B is returned to the temperature controller 31. The temperature controller 31 only needs to concentrate on the temperature control of the heat medium, and it can be easily realized that the temperature controller 31 has a temperature control capability of a level corresponding to high speed traveling such as 200 km / h. .

  Therefore, in the case of the engine test apparatus shown in FIG. 1, the temperature, the flow rate, and the pressure of the cooling water are all simulated for the entire region from low speed running to high speed running of about 200 km / h. The engine characteristics can be measured with high accuracy.

  FIG. 2 is a block diagram showing a second embodiment of the engine test apparatus of the present invention.

The same components as those of the conventional example of FIGS. 4 and 5 and the first embodiment of FIG. 1 are denoted by the same reference numerals as those shown in FIGS. Differences from the first embodiment will be described.

  The engine test apparatus shown in FIG. 2 has a value corresponding to the vehicle speed when the vehicle is actually traveled (the engine 10 or the like remains stationary in the test room or the like, but it does not travel here. A vehicle speed detection sensor 33 for detecting the vehicle speed) is provided. The vehicle speed detection sensor 33 directly detects the rotational speed of the propeller shaft 21 and converts the rotational speed into the vehicle speed.

  Information on the detected vehicle speed is input to the circulation path switching control unit 34 by the vehicle speed detection sensor 33. The circulation path switching control unit 34 sets the circulation path switching valve 32 as follows according to the input vehicle speed. Switch to.

  That is, in the case of a vehicle speed at a level that allows the fan 27 to send wind of an air volume corresponding to the vehicle speed to the radiator 25, the cooling water sent from the engine 10 passes through the radiator 25 and the circulation path switching valve 32. When the circulation path switching valve 32 is switched so as to return to the engine 10 as it is and the vehicle speed is high enough to prevent the fan 27 from sending the wind of the air volume corresponding to the vehicle speed to the radiator 25, the circulation path The switching valve 32 is switched so that the cooling water sent from the engine passes through the radiator 25, passes through the circulation switching valve 32, further passes through the heat exchanger 30, and then returns to the engine 10. . The temperature controller 31 always cools the heat medium to a desired temperature and sends it to the heat exchanger 30. When the cooling water is sent to the heat exchanger 30, the temperature regulator 31 is on standby so that the cooling water can immediately start cooling. Has been.

  If comprised in this way, the cooling water sent out from the engine 10 will return to the engine 10 as it is through a circulation path at the time of low speed driving | running | working and high speed driving | running | working, and the flow volume and pressure of cooling water are water pump 11. Will dominate. Accordingly, the flow rate and pressure of the cooling water can be simulated with high accuracy during actual travel. In the case of traveling at high speed, the cooling water causes an extra pressure drop as much as it passes through the heat exchanger 30. However, the pressure drop is within an allowable error range when performing a characteristic test with a required accuracy. is there.

  Further, during low-speed traveling, the cooling water temperature is the same cooling system as the actual automobile cooling system using the radiator 25 and the fan 27, and can be simulated with extremely high accuracy.

  When simulating high-speed traveling, cooling equivalent to that during actual traveling is performed by both the radiator 25 and the heat exchanger 30. When simulating high-speed driving, cooling with only the heat exchanger 30 is conceivable. However, the cooling system that applies air to the radiator 25 is more suitable for the actual automobile cooling system, and the radiator 25 By using the heat exchanger 30 as a supplement only for cooling that is not sufficient by cooling only by applying the heat, the behavior of the actual automobile cooling system is further enhanced as compared with the case of cooling by the heat exchanger 30 alone. It can be simulated in accuracy.

  FIG. 3 is a timing chart showing an example of the operation of the engine test apparatus of FIG.

  Here, the rotational speed of the engine increases linearly and exceeds the rotational speed corresponding to the vehicle speed of 100 km / h (FIG. 3A). Note that this change in vehicle speed (rotation speed) is merely an example in terms of model, and the rotation speed of the engine changes dynamically according to the test method.

  Here, the circulation path switching valve 32 is switched at a vehicle speed of 100 km / h, and cooling by the heat exchanger 30 is used at a vehicle speed of 100 km / h or more. Therefore, as shown in FIG. 3B, the temperature of the cooling water is suppressed to a level that does not rise too much after the vehicle speed exceeds 100 km / h. The broken line in FIG. 3 (b) shows a case where cooling is attempted only by the radiator 25 without using the heat exchanger 30, and the cooling water temperature continues to rise abnormally because the air volume of the fan 27 is insufficient. It will be. As shown in FIG. 3C, the air volume of the fan 27 can only be generated up to an air volume corresponding to a vehicle speed of 100 km / h, and the air volume corresponding to the vehicle speed of 100 km / h remains unchanged even at a higher vehicle speed. .

  As shown in FIG. 3 (d), the circulation path switching valve 32 is closed (directly connecting the radiator 25 and the engine 10) up to a vehicle speed of 100 km / h, and is opened (radiator 25 and heat) when exceeding 100 km / h. The cooling water path to the exchanger 30 is connected).

  As shown in FIG. 3 (e), the heat exchanger 30 is OFF (cooling water is not fed in and therefore heat exchange is not performed) up to a vehicle speed of 100 km / h, and is ON when the vehicle speed exceeds 100 km / h. (A state where heat is exchanged between the cooling water and the heat medium).

  As shown in FIG. 3 (f), the temperature controller 31 is in an ON state in which the heat medium is always cooled, including during low-speed operation, and is on standby so that it can be dealt with any time when it exceeds 100 km / h. .

1 is a block diagram showing a first embodiment of an engine test apparatus of the present invention. It is a block diagram which shows 2nd Embodiment of the engine test apparatus of this invention. It is a timing chart which shows an example of operation | movement of the engine test apparatus of FIG. It is a schematic diagram of the conventional engine test apparatus in consideration of engine cooling. It is a schematic diagram of the engine test apparatus provided with another conventional engine cooling system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Engine 11 Water pump 21 Propeller shaft 22 Absorption motor 23 Load control part 24 Slot control part 25 Radiator 26 Circulation path 27 Fan 30 Heat exchanger 31 Temperature regulator 32 Circulation path switching valve 33 Vehicle speed detection sensor 3 4 Circulation path switching control part

Claims (1)

In an engine test apparatus that tests an engine characteristic by connecting an engine to an absorption motor,
A temperature controller for adjusting the temperature of the heat medium;
A heat exchanger that exchanges heat between the heat medium whose temperature is adjusted by the temperature controller and the cooling water for cooling the engine ;
A radiator for passing the cooling water;
A fan that applies wind to the radiator;
Both the first cooling water circulation path for returning the cooling water sent out from the engine to the engine via only the radiator of the radiator and the heat exchanger, and both the radiator and the heat exchanger A circulation path switching valve that switches between a second cooling water circulation path that returns to the engine via
An engine test apparatus comprising: a circulation path switching control unit that switches the circulation path switching valve according to a rotation speed of the engine.

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