JPS59141745A - Engine with turbocharger - Google Patents

Abstract

PURPOSE:To increase the low-speed torque of an engine and to thereby lower the specific fuel consumption, by connecting a subsidiary engine to a main engine via power transmitting means, and providing a clutch in said power transmitting means. CONSTITUTION:An engine with a turbocharger shown in the drawing is composed of a main engine 1 and a subsidiary engine 2. The subsidiary engine 2 is connected to the main engine 1 via power transmitting means 12, 20, 21. Further, a clutch 19 is provided on a crankshaft 18 of the subsidiary engine 2, and coupling and uncoupling of the clutch 19 is effected by a lever 22. In case that it is necessary to increase the engine torque at its low-speed operation, the torque of the main engine 1 and that of the susidiary engine 2 are both utilized. Further, at the time of high-speed operation of the engine, the engine torque is increased by means of a turbocharger 4. With such an arrangement, it is enable to increase the low-speed torque of the engine and to thereby lower the specific fuel consumption of the same.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a turbocharged engine, and more particularly to an engine whose output is improved, especially at high speeds, by a turbocharger equipped with a turbine driven by exhaust gas.

By equipping the engine of a large vehicle with a turbocharger, it becomes possible to increase its output and reduce fuel consumption. However, since a turbocharger is equipped with a turbine driven by exhaust gas,
No great effect can be obtained when the engine speed is low. Therefore, such a turbocharged engine has low low-speed torque, which causes problems in starting performance. Therefore, such turbocharged engines are unsuitable for vehicles that require large low-speed torque, such as dump trucks.

One way to improve the low-speed torque of a small-displacement, highly-supercharged turbocharged engine is to improve the efficiency of the turbo compressor, for example.

The turbocharger is made to have a low speed by using a compressor, a packed word impeller, or a wastegate.

However, even with such measures, low-speed torque could not be sufficiently improved. In fact, by taking such measures, a new drawback has arisen: the exhaust pressure increases when the engine rotates at low speed and under light load, which worsens fuel efficiency.

The present invention has been made in view of these problems, and an object of the present invention is to provide a turbocharged engine that prevents deterioration of fuel efficiency in the low-speed light load region of the engine and improves low-speed torque. The purpose is to

The present invention will be explained below with reference to an illustrated embodiment.

The drawing shows a turbocharged engine according to this embodiment, and this engine is composed of a main engine 1 and a sub-engine 2. The main engine 1 is composed of a turbocharged engine similar to the conventional one, and its exhaust manifold 3 is connected to an exhaust pipe 6 via a turbine 5 of a turbocharger t4. On the other hand, main engine 1
The intake manifold 7 is connected to the intake pipe 9 via the compressor 8 of the turbocharger 4.

An air cleaner 10 is connected to this intake pipe 9.

A gear 12 is attached to the crankshaft 11 of the main engine 1, and the gear 12 is connected to a transmission 14 via a clutch 13.

Next, the intake manifold 15 of the auxiliary engine 2 is connected to the intake pipe 9 of the main engine 1 via an intake pipe 16. Also, this auxiliary engine 2 also has an exhaust manifold 17.
is provided. Further, a clutch 19 is provided on the crankshaft 18 of this sub-engine 2, and the crankshaft 18 is connected to a gear 20 via this clutch 19. This gear 2o and the gear 12 are configured to transmit power via a gear 21. To connect and disconnect one clutch, use lever 2.
It is designed to be carried out by 2.

The rotation of this lever 22 is controlled by an air cylinder 23. Air cylinder 23
is connected to an air tank (not shown) via a solenoid valve 24. The opening and closing of the solenoid valve 24 is controlled by a control signal from a micro combi coater 25.

Furthermore, this sub-engine 2 is equipped with a fuel injection pump 26, and this pump 26 is provided with an actuator 27 for controlling supply and cutoff of fuel. This actuator 27 is also actuated by a control signal from the microcomputer 25. The microcomputer 25 is supplied with signals regarding the rotational speed and water temperature of the two engines 1.2, or the amount of depression of the accelerator pedal and clutch pedal of the vehicle equipped with these engines, and the state of the brakes. There is.

In the above configuration, one clutch is connected when the engine requires low-speed torque, that is, when the vehicle starts or climbs a steep slope. That is, the microcomputer 25
Based on the command, the solenoid valve 24 is heard, and the air cylinder 2
3, the clutch 19 is connected via the lever 22. Therefore, the main engine 1 and the auxiliary engine 2 are connected via gears 12, 20, 21, and the output torque of the two engines 1.2 is transmitted to the crankshaft 11 of the main engine 1. Become. Therefore, this torque is applied to the clutch 13 and the transmission 1.
4 to the drive wheels, allowing the vehicle to start or climb a steep slope. At this time, the supply of fuel to the sub-engine 2 by the fuel injection pump 26 is controlled by the actuator 27 based on the command from the micro combi coater 25.

In addition, when the vehicle is running at a medium or high speed and the engine brake is activated, the microcomputer 25 detects information regarding the depression of the accelerator pedal and the clutch pedal, and connects the clutch 19 accordingly. In this state, engine braking is applied by the main engine 1 and the auxiliary engine 2.

Therefore, it becomes possible to apply more powerful engine braking.

On the other hand, when the vehicle is running at medium or high speed, the clutch 19 is disconnected based on instructions from the microcomputer 25, and the actuator 27 starts supplying fuel from the fuel injection pump 26 to the auxiliary engine 2. to stop.

Therefore, in this case, the vehicle is driven only by the output torque of the main engine 1. However, in this case, since the rotation speed of the main engine 1 is quite high,
The exhaust pressure of the engine 1 is also high, so the turbine 5 of the turbocharger 4 is driven at high speed, and the compressor 8 strongly compresses the intake air. High torque can be obtained. Therefore, it becomes possible to sufficiently generate 1 q of torque required for the vehicle to run using only the main engine 1.

As described above, in the turbocharged engine according to this embodiment, when low-speed torque is particularly required, one clutch is connected to extract output from the two engines 1 and 2 respectively. There is. Also, when the engine speed becomes high, the clutch 19 is disengaged and the main engine 1
By increasing the output of the engine with the turbocharger 4, sufficient high-speed torque is generated by 1q. Therefore, by implementing complicated measures on the turbocharger 4, there is no need to improve low-speed torque, or the exhaust pressure does not increase in the case of light loads, and it also reduces fuel consumption when the engine is at low speeds and under light loads. This makes it possible to prevent Furthermore, since the auxiliary engine 2 is mainly used when the vehicle starts or when climbing a steep slope, its operating time is short, and therefore there is no need for a design that can withstand a large load. , it will be advantageous in terms of cost. Furthermore, it is also possible to share the auxiliary equipment of the main engine 1 and the auxiliary engine 2. In addition, sub-engine 2
can be used as a starter for the main engine 1 with low starvation.

As described above, the present invention consists of a main engine and a sub-engine, and when low-speed torque is required, the main engine and the engine are connected via a clutch and a transmission device, and this This makes it possible to utilize the torque of two engines, and at the same time, during high-speed rotation, a turbocharger installed in the main engine is used to improve output. Therefore, according to the present invention, there is no need to take measures to improve the torque of the turbocharger that is required during low speed rotation, and it is also possible to improve fuel efficiency when the engine is under light load.

[Brief explanation of the drawing]

The drawing is a plan view showing a turbocharged engine according to an embodiment of the present invention. In addition, in the symbols used in the drawings, 1... Main engine 2... Sub engine 4... Turbocharger 5...・
...Turbine 8...Compressor 12.20.21...Gear 19...Clutch 23...Air cylinder. Applicant Hino Motors Co., Ltd.

Claims (1)

[Claims] In an engine whose output is improved especially at high speeds by a turbocharger equipped with a turbine driven by exhaust gas, an auxiliary engine is provided, and the auxiliary engine is connected to the main engine via a transmission, Furthermore, this turbocharged engine is characterized by having a clutch installed in this transmission device.