JPH02119633A - Control device for diesel engine with supercharger - Google Patents

Abstract

PURPOSE:To reduce idle knocking sound occurring during cold idle-operation of an engine by providing a control section for drivingly controlling a supercharger to execute supercharging action during a fixed operation at the cold idling and the cold loading operation of a diesel engine. CONSTITUTION:A supercharger 12 is provided on the midway of an intake passage 10 between a carburetor 6 and an air cleaner 4 on an intake system of a diesel engine, and a bypass passage 14 is provided to bypass the supercharge 12, and a solenoid valve 16 is provided on the midway of the passage 14. The supercharger 12 is driven by the torque of an engine output shaft 20 through a transmitting mechanism consisting of pulleys 22, 24 and a belt 26, and an electromagnetic clutch 30, which is engaged by a control section 32 in the fixed state of engine operation during the cold idling and the cold loading operation of the engine 8, and controlled for performing supercharging action.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a control device for a diesel engine with a supercharger, and in particular, a supercharger is provided in the intake system, and an electromagnetic clutch is connected and disconnected depending on the accelerator opening and engine speed. , relates to a supercharged diesel engine that performs supercharging control of the supercharger.

[Prior Art] Some internal combustion engines are equipped with a supercharger in order to improve output, fuel consumption rate, and the like. This supercharger includes an exhaust supercharger that is driven using the exhaust energy of the internal combustion engine, and a supercharger (S/C) that is a mechanical supercharger that is driven using the power of the internal combustion engine. etc.

Examples of internal combustion engines equipped with a supercharger, which is a mechanical supercharger, include the method for controlling a vehicle equipped with a supercharged engine disclosed in Japanese Patent Laid-Open No. 57-203823, and the method disclosed in Japanese Patent Laid-Open No. 58-85934. There is a supercharger system for an internal combustion engine disclosed in .

[Problems to be solved by the invention] By the way, in conventional control devices for diesel engines equipped with a supercharger, there are those that constantly drive the supercharger, which is a mechanical supercharger, without using an electromagnetic clutch, and those that use an electromagnetic clutch. Some systems control the supercharger by connecting and disconnecting an electromagnetic clutch depending on the accelerator opening and engine speed.

In addition, the supercharger is controlled by connecting and disconnecting the electromagnetic clutch, as shown in Figure 5, the electromagnetic clutch is connected when the accelerator opening is θ or more, and the electromagnetic clutch is connected when the engine speed is less than N. The electromagnetic clutch is disconnected.

For this reason, in the former case mentioned above, by constantly supercharging with the supercharger, it is possible to reduce the idle knocking noise when the engine is cold and improve warm-up performance, but the supercharger is not activated even during startup. Being driven causes deterioration in starting performance and also has the disadvantage of deteriorating fuel efficiency.

In addition, the latter type, contrary to the former type mentioned above, has good starting performance and can prevent an increase in drive loss at the time of starting, but does not perform supercharging during cold idling, reducing idle knocking noise. However, there are disadvantages in that it is not possible to improve warm-up performance.

Furthermore, by lowering the accelerator opening and engine speed settings to connect the electromagnetic clutch, supercharging is possible during cold idling, but overcharging can also be performed when supercharging is not required, such as during warm-up. This has the disadvantage that fuel consumption deteriorates, which is economically disadvantageous.

[Objective of the Invention] In order to eliminate the above-mentioned disadvantages, it is an object of the present invention to provide a control device for a diesel engine with a supercharger that is configured to control the control device during predetermined engine operating conditions during cold idling and cold load operation of the diesel engine. By installing a control unit that controls the supercharger to connect the electromagnetic clutch and perform supercharging, the electromagnetic clutch is connected to perform supercharging during cold engine idle and cold load operation, thereby eliminating idle knock during cold engine operation. The object of the present invention is to realize a control device for a diesel engine with a supercharger that can reduce noise, improve warm-up performance, and improve startability at the same time.

[Means for Solving the Problems] In order to achieve this object, the present invention provides a supercharger in the intake system and controls the supercharger by connecting and disconnecting an electromagnetic clutch depending on the accelerator opening and engine speed. In the control device for a diesel engine with a diesel engine, the control unit controls the supercharger to connect the electromagnetic clutch and perform supercharging when the diesel engine is in a predetermined engine operating state during cold idle and cold load operation. It is characterized by having been provided.

[Function] With the above-described configuration, when the diesel engine is in a predetermined engine operating state during cold idle and cold load operation, the control section connects the electromagnetic clutch to perform supercharging, and when the diesel engine is cold This reduces idle knocking noise and improves warm-up performance, while also improving starting performance.

[Examples] Examples of the present invention will be described in detail below based on the drawings.

1 to 4 show embodiments of this invention. 1st
In the figure, 2 is a control device for a diesel engine.

This diesel engine control device 2 has an engine intake system that extends from an air cleaner 4 through an intake chamber, for example, a carburetor 6, to a diesel engine 8. In addition to providing a supercharger 12 in the
A bypass passage 14 is provided to bypass this supercharger 12.

A normally open solenoid valve 16 is provided in the middle of the bypass passage 14, and a solenoid 18 for opening and closing the solenoid valve 16 is provided near the solenoid valve 16.

The supercharger 12 is driven by the rotational force of the engine output shaft 20 of the diesel engine 8, and supercharges intake air to the diesel engine 8. In other words,
The supercharger 12 transfers the rotational force of the engine output shaft 20 to the first and second boots 1J22, 24 and the belt 26.
is transmitted to the drive shaft 28 of the supercharger 12 via the electromagnetic clutch 30.
is provided.

When the electromagnetic clutch 30 is in a disengaged state, that is, when a solenoid (not shown) of the electromagnetic clutch 30 is de-energized, the rotational force of the engine output shaft 20 is not transmitted to the drive shaft 28, and the supercharger 12
does not perform supercharging.

A control section 32 is provided in communication with the electromagnetic clutch 30, and the control section 32 controls the diesel engine 8.
The electromagnetic clutch 30 is connected to control the supercharger 12 to perform supercharging during predetermined engine operating conditions, such as cold idle and cold load operation.

More specifically, as shown in FIG. 1, the control unit 32 generates a starter signal 34 that detects ON/OFF operation of a starter (not shown), a complete explosion signal 36 that detects a complete explosion state when starting is completed, and Gear neutral signal 3 that detects the gear neutral state by a neutral switch that does not
8, a cooling water temperature signal 40 for detecting the temperature of the diesel engine 8, for example, the temperature of the cooling water, and an accelerator opening signal 42 for detecting the engine load state, are connected to each other,
These signals connect the electromagnetic clutch 30 and drive the supercharger 12 to perform supercharging when the engine is in a predetermined operating state during cold idling, that is, when the terminal voltage of an alternator (not shown) changes from the L state to the H state, for example. It is something that is controlled to be carried out.

Further, the control section 32 controls the electromagnetic clutch 30 to be connected and the supercharger 12 to be driven to perform supercharging during gear shift during cold load operation.

Next, the effect will be explained.

When the diesel engine 8 is started, regardless of whether it is cold or warmed up, the electromagnetic clutch 30 of the supercharger 12 is disconnected by turning on the starter signal, and supercharging is not performed.

When the cooling water temperature is less than t° C. and the engine is in a neutral state, when it is determined that the engine is in cold idle mode, the control section 32 connects the electromagnetic clutch 30 of the supercharger 12 to perform supercharging.

Furthermore, during cold engine load operation, the electromagnetic clutch 30 of the supercharger 12 is disconnected by gear shift due to the load operation being performed even when the engine is cold. and supercharging control is performed.

Furthermore, during warm-up idling when the cooling water temperature is t''C0 or more and in the neutral state, even if the gear is in the neutral state after the start is complete, the control section 32 This disengages the electromagnetic clutch 30 of the supercharger 12, thereby preventing unnecessary supercharging.

Furthermore, during warm-up load operation, the electromagnetic clutch 30 of the supercharger 12 is turned on and off by the control section 32 in accordance with the accelerator opening signal 42 to perform supercharging control.

As a result, it is possible to reduce idle knock noise during cold engine operation such as during cold engine idle or cold load operation, improve warm-up performance, and prevent deterioration of start performance, which is advantageous in practice. be.

Further, by operating the supercharger 12 after starting the engine until a predetermined cooling water temperature is reached, noise can be efficiently reduced and the idling state can be stabilized.

Furthermore, during cold load operation or warm-up load operation, the electromagnetic clutch 30 of the supercharger 12 is activated by an accelerator opening signal 42.
As is clear from the relationship between load and fuel consumption in FIG. 4, by controlling the supercharging to be intermittent depending on the fuel consumption, it is possible to prevent deterioration in fuel consumption, which is economically advantageous.

Note that the present invention is not limited to the above-described embodiments, and various modifications can be made.

For example, in the embodiment of the present invention, an accelerator opening signal is input to the control section when detecting the engine load state, but instead of this accelerator opening signal, an engine rotation speed signal is input, It is also possible to detect load conditions.

Further, when controlling the connection start operation of the electromagnetic clutch according to the alternator L terminal voltage in the embodiment of the present invention, as shown in FIG. It can also be controlled to delay (by seconds).

[Effects of the Invention] As described above in detail, according to the present invention, when the control device for a diesel engine with a supercharger is in a predetermined engine operating state during cold idling and cold load operation of the diesel engine, the electromagnetic clutch is activated. A control unit is provided to control the supercharger to connect the engine and perform supercharging, so it is possible to reduce the idle knocking noise when the engine is cold, improve warm-up performance, and prevent deterioration of starting performance. This is practically advantageous because it can be prevented. Further, by operating the supercharger after starting the engine until the temperature of the cooling water reaches a predetermined value, noise can be reduced and the idle state can be stabilized. Furthermore, by controlling the supercharging so that the electromagnetic clutch of the supercharger is connected or disconnected depending on the engine operating state during load operation in cold or warm conditions, deterioration of fuel efficiency can be prevented, which is economically advantageous.

[Brief explanation of drawings]

1 to 4 show embodiments of the present invention, FIG. 1 is a schematic diagram of a diesel engine control device, FIG. 2 is a logic circuit diagram of a diesel engine control device, and FIG. 3 is a diesel engine control device. The time chart of FIG. 4 is a diagram showing the relationship between fuel efficiency and load. FIG. 5 is a time chart of a diesel engine control device showing the prior art of the present invention. In the figure, 2 is a diesel engine control device, 4 is an air cleaner, 6 is a carburetor, 8 is a diesel engine,
10 is an intake passage, 12 is a supercharger, 14 is a bypass passage, 16 is a solenoid valve, 18 is a solenoid, 20 is an engine output shaft, 22 is a first pulley, 24 is a second pulley, 26 is a belt, and 28 is a drive shaft. , 30 is an electromagnetic clutch, 32 is a control unit, 34 is a starter signal, 36 is a complete explosion signal, 38 is a gear neutral signal, 40 is a cooling water temperature signal, and 42 is an accelerator opening signal. Figure 1 Patent Applicant Suzuki Motor Co., Ltd. Representative Patent Attorney Yoshimi SaigoWi
N 猾

Claims (1)

[Claims] 1. In a control device for a diesel engine with a supercharger that includes a supercharger in the intake system and controls the supercharger by connecting and disconnecting an electromagnetic clutch depending on the accelerator opening degree and engine speed, the diesel engine is controlled during cold idling and cold load operation. 1. A control device for a diesel engine with a supercharger, comprising: a control section that controls the supercharger to connect the electromagnetic clutch and perform supercharging when the engine is in a predetermined operating state.