JPH05620A - Turbo heater system - Google Patents

Abstract

PURPOSE:To eliminate retardation at the time when a car starts concerning a turbo heater system for compensating for a usual heater device. CONSTITUTION:The upstream side and the downstream side of a control valve 5 provided in a main exhaust passage 3 are connected to each other by a subexhaust passage 7 in which a turbine 6 of a turbo heater 6 is provided, and the inside and outside of a car are connected to each other by a connecting passage 8 in which a blower 6b of the turbo heater 6. When the speed of rotation in a low rotating speed area is below a specified value, the control valve 5 is fully opened to stop the turbo heater.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention uses an exhaust gas to drive a turbine to rotate, and a blower connected to the turbine pressurizes air to raise its temperature, and supplies this air to the interior of a vehicle for heating. The present invention relates to a turbo heater system for a vehicle equipped with an internal combustion engine.

[0002]

2. Description of the Related Art A diesel engine has a small amount of heat exhausted from the engine because it has good thermal efficiency. Therefore, when a diesel engine vehicle is used in a cold region or the like, a normal heater device that uses the exhaust heat of the engine is not sufficient, and another heating device that compensates for this is required.

As this heating device, an electric one can be considered, but it is not preferable because the battery mounted on the vehicle becomes large, and the above-mentioned turbo heater as described in JP-A-1-218914. Devices are receiving attention.

Since this turbo heater device operates efficiently in a low rotation range of a diesel engine in which the amount of exhaust gas is relatively small, it is smaller than a general turbocharger for supercharging. .. Along with that, the turbine sub-exhaust passage of the turbo heater branched from the main exhaust passage is relatively thin, and cannot pass a large amount of exhaust gas in a high load or high rotation range of a diesel engine, so in these regions, The control valve provided on the downstream side of the sub exhaust passage branch of the main exhaust passage is fully opened to stop the turbo heater, but in these areas, the exhaust heat from the diesel engine is large and a normal heater is sufficient. A good heating effect is obtained.

Further, in a low speed and high load range of a diesel engine, white smoke is generated due to deterioration of combustion state,
When the turbo heater is activated, the amount of white smoke generated may further increase as exhaust resistance increases.The turbo heater is stopped in this area as well, but it is an area that is rarely used when using a car. It doesn't matter.

As described above, the turbo heater can be used in a region other than the above range, but as described above, a slight torque decrease occurs as the exhaust resistance increases during use, and this torque fluctuation is moderated. In order to obtain good drivability, it is common to provide an intermediate region near the boundary with the stop region in the operating region, where the control valve in the main exhaust passage is gradually opened and closed.

[0007]

As described above, the diesel engine vehicle having the turbo heater is used in a cold region, and the road surface is often frozen in such a place. In such a case, the traveling road surface is slippery, and when the vehicle is started, unless the accelerator is stepped on gradually, the tire will slip and the vehicle will not start smoothly.

When the vehicle starts, it is an intermediate region in the region where the above-mentioned turbo heater can be used, and a slight torque decrease occurs. Therefore, until the desired torque is reached, the gentle accelerator depression operation described above is performed. It will take some time. During that time, the driver feels the vehicle is sluggish.

Therefore, an object of the present invention is to provide a turbo heater system capable of eliminating the rattling at the time of starting the vehicle.

[0010]

In order to solve the above-mentioned problems, a turbo heater system in a vehicle equipped with an internal combustion engine according to the present invention includes a control valve provided in a main exhaust passage, and a control valve provided in the main exhaust passage. The upstream side and the downstream side of the control valve are connected to each other, and an auxiliary exhaust passage provided with a turbine of a turbo heater, and a communication passage for guiding warm air discharged from a blower connected to the turbine into a vehicle interior, It is characterized in that the control valve is fully opened and the turbo heater is stopped when the rotational speed of the internal combustion engine is equal to or lower than a predetermined rotational speed in a low rotational speed range.

[0011]

In the turbo heater system described above, since the turbo heater is stopped when the number of revolutions of the internal combustion engine is less than the predetermined number of revolutions, the torque is prevented from decreasing, and the desired torque is reached even when the accelerator pedal is gradually depressed. It takes less time than before, and the driver does not feel any flutter in the car.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a block diagram of a general turbo heater. In the figure, 1 is a diesel engine, 2 is an intake passage, and 3 is a main exhaust passage. An air cleaner 4 is provided at an end of the intake passage 2 opposite to the diesel engine 1.

A control valve 5 is provided in the main exhaust passage 3, and an upstream side and a downstream side of the control valve 5 are connected by a sub exhaust passage 7 provided with a turbine 6a of a turbo heater 6. A blower 6b connected to a turbine 6a of a turbo heater 6 is provided in a communication passage 8 that connects the downstream side of the air cleaner 4 and the interior of the vehicle.

An operating device (not shown) is connected to the control valve 5, and the opening / closing is controlled according to the two-dimensional map shown in FIG. Although not shown, a control valve is also provided on the upstream side and / or the downstream side of the blower 6a of the turbo heater 6 in the communication passage 8 to adjust the amount of supplied air in order to keep the vehicle interior at a predetermined temperature. Good.

FIG. 2 is a two-dimensional map of the engine speed and the lever opening that is linked to the accelerator, which shows the operating range of the turbo heater. In the figure, the upper side of the straight line A and the straight line B is in the operating state in which the lever opening indicating the load is large or the rotational speed is high, and the control valve 5 of the main exhaust passage 3 is fully opened to generate a large amount of exhaust gas. This is an area in which the turbo heater 6 must be stopped.

The upper side of the straight line C is a region where the engine combustion is bad and white smoke is generated, and the turbo heater 6
If the exhaust resistance is increased by using, the amount of white smoke generated is further increased, and this is also an area where the turbo heater 6 is stopped.

The former region has a relatively large amount of heat exhausted from the diesel engine and can be sufficiently heated by a normal heater without using a turbo heater, and the latter region is an operation which is practically not used. This is a state, and even if the use of the turbo heater is stopped in these areas, there is practically no problem.

When the exhaust gas passes through the auxiliary exhaust passage 7, the turbo heater 6 rotates the turbine 6a of the turbo heater 6 provided therein, and the blower 6b connected to the turbine 6a passes through the air cleaner 4. The air in the communication passage 8 is pressurized to raise its temperature, and the air is supplied to the inside of the vehicle to heat the inside of the vehicle.

Therefore, when the turbo heater 6 is used on the lower side of the straight lines A, B and C described above, a torque decrease occurs due to an increase in the exhaust resistance, and this turbo fluctuation is moderated in order to make the torque fluctuation gentle. Straight line A in the heater operating area,
The vicinity of B and C is an intermediate region where the control valve 5 of the main exhaust passage 3 is gradually opened and closed without being fully closed, and the inside thereof is a complete operating region where the control valve 5 is fully closed (one point in FIG. 2). (Inside the chain line)
Is.

The above-described control of the turbo heater is the same as that of the conventional example, but according to the present embodiment, the turbo heater is stopped in a region below a predetermined rotation speed (1000 rpm in FIG. 2) in the low rotation range. In other words, the hatched portion in FIG. 2 where the turbo heater is conventionally used as the intermediate area is used as the turbo heater stop area in this embodiment.

[0021] As a result, when the vehicle is started when the running road surface is frozen and slippery, the turbo heater is in a stop region when the lever opening during idle is exceeded and the accelerator is used to prevent the tire from idling. Even if the aforementioned interlocking levers are gradually opened, the desired torque can be reached in a relatively short time because the torque does not decrease, and the vehicle can be started without rattling.

The shaded area in FIG. 2 is an area used when the vehicle starts and climbs a high gear.
The driving conditions are not very favorable for the driver. Conventionally, since the turbo heater was used also in this area, it took a long time to escape from this area due to the decrease in torque accompanying it, but as described above, this embodiment enables the escape in a short time. , The drivability is improved.

Although the turbo heater cannot be used in this region, it does not pose a problem because it escapes in a short time as described above.

The dots in FIG. 2 show the state of actual city driving in a cold region using the turbo heater system of this embodiment, but by stopping the turbo heater in the shaded region, that region is shown. It can be seen that the car is hardly driven inside, and it is clear that there is no problem even if the turbo heater is stopped in the shaded area.

In this embodiment, the turbo heater is operated even when the engine speed is lower than the above-mentioned predetermined number of revolutions. However, this means that the vehicle is stopped when the engine is idle and the torque is reduced to some extent. This is because there is no problem in drivability.

In addition, since the vehicle has been sluggish at the time of starting the vehicle in the past, the driver may step on the accelerator too much in order to obtain a desired torque quickly, which results in deterioration of fuel consumption. Is also improved.

In the present embodiment, the intermediate region of the low rotation speed region is eliminated, but the generated torque is absolutely low in the low rotation speed region, and when the desired torque is obtained, it enters the operation region of the turbo heater. However, the amount of torque reduction due to the operation is slight, and the drivability at this time is not so different from the conventional one.

[0028]

As described above, conventionally, by operating the turbo heater in the low speed rotation range, there is a driving state of the vehicle in that range which is not preferable in terms of drivability such as the rattling of the vehicle at the time of starting. However, by stopping the turbo heater in the area according to the present invention, the driving state of the vehicle in the area is almost eliminated, and the actual operating area of the turbo heater is not reduced, thereby improving the drivability of the vehicle. be able to.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a configuration of a general turbo heater.

FIG. 2 is a two-dimensional map of an engine rotational speed and a lever opening degree linked to an accelerator, which shows an operating region of a turbo heater according to the present invention.

[Explanation of symbols]

 1 ... Diesel engine 3 ... Main exhaust passage 5 ... Control valve 6 ... Turbo heater 6a ... Turbine 6b ... Blower 7 ... Sub exhaust passage 8 ... Communication passage

Claims (1)

Claim: What is claimed is: 1. A control valve provided in a main exhaust passage communicates with an upstream side and a downstream side of the control valve in the main exhaust passage,
A turbo heater is provided with a sub-exhaust passage provided with a turbine, and a communication passage for introducing warm air discharged from a blower connected to the turbine into the vehicle interior. A turbo heater system in a vehicle equipped with an internal combustion engine, wherein the control valve is fully opened to stop the turbo heater.