JPS58185940A - Torque fluctuation restraining device for engine - Google Patents

Abstract

PURPOSE:To maintain a battery charging amount properly by making an alternator generate electricity in increasing torque generated in a crank-shaft to restrain torque fluctuation while increasing generated energy of the alternator in the condition of discharging the battery. CONSTITUTION:Time of increasing torque generated in a crankshaft is detected by a timing detecting means 3 including a crankshaft sensor 7, and current is supplied to a field core 1a of an alternator 1 through a field controlling means 2 including a single multiplexer 9 and an adding circuit 10 in increasing the torque to make the alternator 1 generate electricity. Thus, reversal torque is generated in the crankshaft to restrain fluctuation of rotational torque. A battery condition detecting means 13 including a comparator 17 is also connected to said adding circuit 10 which adds the correction signal V3 of the comparator 17 to the signal of the single multiplexer 9 when said signal V3 is generated from the comparator 17, i.e. when a battery 5 is under the discharging condition to increase generated energy of the alternator 1.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an engine torque fluctuation suppressing device.

Generally, in an engine, in order to convert the explosive force in the cylinder into rotation of the crankshaft, rotational torque fluctuations occur on the crankshaft in synchronization with the explosion while the crankshaft rotates. The rotational torque fluctuations generated in the crankshaft cause vibrations, rattling noises, etc., and have various harmful effects.

Conventionally, as a method for suppressing the rotational torque fluctuation of the crankshaft, as shown in Japanese Patent Application Laid-Open No. 1983-1986/GJ'/, a method of generating a magnetic flux that rotates integrally with the engine crankshaft has been proposed. A technology for suppressing engine torque fluctuations by providing a second magnetic flux generating means on the fixed side and generating magnetic torque in synchronization with rotational torque fluctuations generated in the crankshaft and in an opposite phase to the rotational torque fluctuations. is proposed.

However, in the above proposed technique, it is necessary to separately form the second/second magnetic flux generating means in the conventional engine.
There may be a cost disadvantage.

In view of the above, the present invention includes a timing detection means for detecting when the torque increases due to rotational torque fluctuations occurring in the crankshaft in synchronization with engine explosion, and a timing detection means for detecting when the torque increases due to the rotational torque fluctuation generated in the crankshaft in synchronization with the explosion of the engine. A field current control means for applying a field current to the field coil of the engine is provided to generate a reverse torque on the crankshaft when the torque increases, and to suppress rotational torque fluctuations generated on the crankshaft in synchronization with engine explosion. , suppresses rotational torque fluctuations by using an existing alternator,
A battery state detection means for effectively preventing vibrations, rattling noises, etc. and detecting the discharge state of the battery; and a correction means for supplementing the field current control means so as to always apply the current to the field coil, thereby preventing the battery from becoming over-discharged and always maintaining a good state of charge of the battery. It is an object of the present invention to provide a torque fluid dynamic suppression device.

Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 7, reference numeral 1 denotes an alternator equipped with a field coil 1d and a stator coil 1b, and a field current control means 2 is connected to the field coil 1a of the alternator 1. A timing detecting means 6 is connected to the timing detecting means 6. The timing detection means 6 detects when the rotational torque rapidly increases which is generated on the crankshaft (not shown) in synchronization with the explosion of the engine, and the field current control means 2 detects the signal from the timing detection means 6. In response to this, a field current is applied to the field coil 1d of the alternator 1 when the torque increases.

On the other hand, a battery 5 and an electric load 6 such as a lamp are connected to the stator coil 1b of the alternator 1 via a rectifier circuit 4.
or connected.

・,1 The crank angle sensor 7 constituting the timing detecting means 6 outputs a detection signal when the piston of each cylinder is at the top dead center position, and the detection signal of the crank angle sensor 7 has a waveform. The signal is input to a shaping circuit 8 and shaped into a rectangular wave.

The signal of the waveform shaping circuit 8 is outputted to the monostable multivibrator 9 of the field current control means 2, and is made into a signal having a predetermined pulse width corresponding to the time during which the field current is applied by this monostable multivibrator 9. is amplified by the drive circuit 11 via the adder circuit 10 and applied to the field coil 1a of the alternator 1 at a predetermined timing.

The field current applied to the field coil 1a is applied when the torque increases due to rotational torque fluctuations occurring in the crankshaft, and when this torque increases, the alternator 1 generates electricity, causing the crankshaft to generate a reverse torque. This is to suppress fluctuations in rotational torque that occur on the crankshaft in synchronization with engine explosion.

That is, for example, in a cycle cylinder engine, explosion occurs twice during two revolutions of the crankshaft, so rotational torque fluctuations as shown in FIG. 2A occur.

On the other hand, the timing detection means 3 and the field current control means 2 cause the !th! A field current as shown in Figure H is applied to the field coil 1a of the alternator 1 when the rotational torque fluctuation occurring in the crankshaft increases. A reverse torque (reverse torque) is generated, and the combination of the load torque C and the rotational torque A results in a crankshaft composite torque as shown in FIG. 2 (1), and its fluctuation range is suppressed to be small.

The addition circuit 10 also constitutes a correction means 12 that increases the amount of power generated by the alternator 1 when the battery 5 is in a discharged state. Means 16 is also connected. The battery state detection means 13 detects the discharge state of the battery 5, and the correction means 12 receives the signal from the battery state detection means 16 and adjusts at least a predetermined field when the battery 5 is in the discharge state. This supplements the primary field current control means 2 so that a short current is always applied to the field coil 1a.

The battery condition detecting means 16 detects a current change from both ends of a resistor 14 connected in series with the battery 5, amplifies this with a differential amplifier circuit 15, and for this amplified value 1,
The set value ■6 is added by the adder circuit 16, and this adder circuit 1
The signal 2 of No. 6 is output to the comparator 17.

The comparator 17 uses the output ■2 of the adder circuit 16 as the reference value ■.

Compare with this standard value■. is set according to the capacity of the battery 5, etc. so that the battery 5 does not become over-discharged (battery becomes too dark) under actual operating conditions, and is the output V2 of the adder circuit 16 or this value ■. When the voltage becomes lower, the comparator 17 outputs the signal V8. In other words,
■o and ■. When L7 is low, the current i becomes negative and the comparator 17 outputs V8 in a discharging state in which power is not supplied from the battery 5 to the electric load. In addition,
V.

■. It is appropriately set within the range of ≦■o.

When the signal v8 is output from the comparator 17, that is, when the battery 5 is in a discharged state, the adder circuit 10 applies the correction from the comparator 17 to the signal from the stable multi-by-break 9. The power generation amount of the alternator 1 is increased by adding the signal 8 and applying at least a predetermined field current to the field coil 1a at all times.

Note that the peak value of the field current is regulated by the supply voltage of the adder circuit 10, so its value hardly changes, and as the effective value rises due to the constant addition of the correction signal 8, the power generation amount of the alternator 1 increases. It is something to do.

The present invention is not limited to the structures of the two embodiments described above, but includes various modifications. That is, in the above embodiment, the field current may be corrected by adding a fixed correction signal 8, or the added value may be corrected steplessly according to the magnitude of the current 1.

In addition, as the timing detector 1 and 6, a device that detects the ignition pulse of the engine from the ignition circuit may be used.In that case, a delay circuit is provided to detect the field current at a time delayed by a predetermined amount from the ignition timing. It is provided so as to apply a peak value of .

As explained above, according to the present invention, by providing the timing detection means and the field current control means, as well as the battery state detection means and the correction means,
It is possible to generate a reverse torque on the crankshaft when the torque increases, and to suppress the rotational torque fluctuation that occurs on the crankshaft in synchronization with engine explosion, and it is possible to improve harmful effects such as vibration and teeth rattling noise. This can be done by using an existing alternator, and it has the advantage of being cost-effective. At the same time, when the battery is in a discharged state, it increases the amount of electricity generated and charges the battery, thereby preventing insufficient charging. This is something that can be prevented from occurring.

[Brief explanation of drawings]

Figure 7 is a schematic configuration diagram showing one embodiment of the present invention, Figure A
-1) is an explanatory diagram showing the torque fluctuation suppressing effect.

Claims (1)

[Claims] (11) Timing detection means for detecting when torque increases due to rotational torque fluctuations occurring on the crankshaft in synchronization with engine explosion; a field current control means for applying a field current, a battery state detection means for detecting a discharge state of the battery, and a field current of at least a predetermined amount always applied to the field coil when the battery is in a discharge state in response to a signal from the battery state detection means. and a correction means for correcting the field current control means so as to apply a reverse torque to the crankshaft when the torque increases, thereby suppressing rotational torque fluctuations occurring in the crankshaft in synchronization with engine explosion. An engine torque fluctuation suppressing device characterized by: