JPS60160342A - Vehicle charger - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a new system configuration for a vehicle alternator.

[Background of the invention]

In recent years, there have been significant improvements in generators themselves, with the aim of making them more compact, faster, and more powerful, but on the other hand, as pulleys have become smaller and load torque has increased, they have become increasingly disadvantageous in terms of belt slip. For example, recently poly V belts have been widely used to accommodate pulleys with smaller diameters and higher speeds, but these belts have the following characteristics: 1) They are less likely to slip in warm conditions, but are more likely to slip in cold or cold conditions. When the engine starts in cold weather, momentary slips often occur due to the above-mentioned belt characteristics and the large generator load at the time of start. Such belt slipping may cause discomfort to the vehicle user or may cause damage to the belt itself. In reality, excessive belt tension has been applied to prevent such instantaneous belt slip. In order to ensure the necessary durability against bearing damage and frame breakage in response to such excessive tension, generator bearings inevitably become larger, which increases the cost of the generator and reduces the degree of freedom in functional design. Problems were arising.

[Object of the present invention]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, it is an object of the present invention to provide a vehicle charging device that prevents instantaneous belt slip when starting an engine without applying excessive tension to the belt.

[Configuration of the present invention]

The present invention is provided with means for detecting a slip of the generator drive belt, and also provided with an excitation force control means for weakening the excitation (2) of the field pole to reduce the power generated when a slip occurs.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention shown in the drawings will be described. 1st
The figure is a schematic diagram of an electric circuit showing the configuration of one embodiment of the vehicle charging device according to the present invention, in which 1 is a vehicle engine, and a vehicle alternator is connected to a pulley 4 via a generator drive belt 5 by a crank pulley 2. 3, and the ignition pulse detector 6 of the engine 1 is also connected to this vehicle alternator 3.
is connected to. 7 is an excitation coil of the rotating field pole.

A stator provided with a three-phase armature winding 8 is located on the outer periphery of the excitation coil 7 of the field pole. Reference numeral 9 denotes a voltage control device that adjusts the voltage of the output terminal 10 of the generator 3, and controls the storage battery 11 and the vehicle key switch 12, which are the vehicle electrical loads.
, the generator output section 13, the terminal 14 connected to the armature winding 8, the generator body earth terminal I5, the exciting current switching element 16, and the switching control element 17.
A conventional voltage control (3) having a terminal 18 connected to
) It is a functional part. Reference numeral 19 denotes a flywheel diode that takes into consideration the current inertia effect of the excitation coil 7 of the field pole. 20
．． 21 is an F/V converter, and comparators 22 and 23 are further connected to the duty i1i control &28, the engine ignition pulse detector 6, and the terminal 1.
4 is connected.

The voltage control function unit 24 of the generator 3 is a collection of the above-mentioned functional parts, and is built into the generator 3.

Next, the operation of the vehicle charging device configured as described above will be explained.

The generator field poles are rotated by the engine 1 via the belt 5, and the armature winding 8 is given a rotating magnetic field to generate three-phase power, and the rectifier 30 connected to the armature winding 8 is Converts the power to DC and connects it to the external storage battery 11 from the output terminal 10
etc. receive current supply. Storage battery 11 when load demand is high
The voltage control device 9 detects this and increases the potential of the terminal 18 to increase the conductivity of the switching element 16, increasing the excitation current 25 flowing to the excitation coil 7 (4). The storage battery voltage gradually rises as the power generation output increases in response to the load demand, which increases the power generation output 26. When it exceeds a certain predetermined value, the voltage control device 9 acts inversely to the series of actions described above to increase the power generation output. lower. The above operation is a common voltage control operation known in conventional generators.

Next, the operation of the characteristic portion of the present invention will be explained.

The F/V converter 20 is connected to a terminal 14 connected to the generator armature winding 8, receives the frequency of the electromotive force as a generator rotational speed signal 27, and converts this into a voltage value. , as one of the inputs of the comparator 22. On the other hand F
/V converter 21 receives the engine ignition pulse signal as engine rotation signal 27', converts it into a voltage value, and sends it as the other input of comparator 22. The comparator 22 receives the generator rotational speed signal 27 and the engine rotational signal, and sends out the difference between the rotational speeds as an output to another comparator 23 . The comparator 23 compares the voltage due to the difference between the two rotational speeds with the reference voltage, and the duty controller 28 detects the difference (5), and sets 0 potential when there is no difference between the engine rotational speed and the generator rotational speed. , when there is a deviation, that is, a slip, the time proportion of the positive potential is increased in proportion to the magnitude of the deviation and is applied to the base of the switching control element 17 as an output signal. Due to this, the switching of the excitation current switching element 16 is controlled to turn on and off in priority to the ON command signal issued by the voltage control device 9 of the conventional function, and the excitation current 25 is lowered to reduce the generated power. 26 is forcibly lowered.

The above configuration achieves the effect of continuously reducing the required torque of the generator, which is one of the causes of slippage, until the slippage stops.

In the embodiment shown in FIG. 1, the slip signal is calculated and extracted from the generator electromotive force and the engine ignition pulse, but the slip signal is detected by detecting sound, vibration, or rapid changes in the generator rotation speed. A signal may also be used. Furthermore, in the above embodiment, the slip signal is directly given to the excitation current switching element base as an on/off command signal (6), but it is inputted to the storage battery voltage detection control function section so that it operates as if there is a change in the storage battery voltage. A method of controlling the excitation current may also be used. Alternatively, a method may be adopted in which the reference voltage of a comparator that detects a change in storage battery voltage is lowered during a slip, thereby lowering the excitation current.

[Effects of the present invention]

As mentioned above, in the vehicle charging device according to the present invention,
In addition to providing a slip detection device for the generator drive bell I, we also provide an excitation force control means that weakens the excitation of the field pole and reduces the power generated when a slip occurs, so the slight moment when a belt slip occurs can be detected. It is possible to limit the amount of power generated by the generator by instantaneously lowering the excitation current to the maximum amount of power generation without causing the belt to slip, making it possible to detect slips inexpensively and reliably, and to prevent belt slips. This has a great effect. Note that the opportunity for belt slip is limited to the instant of engine sister 1- in cold and cold conditions, or to a small range of the rotation range S where the generator torque curve A has a high occurrence of slip as shown in Fig. 2. The reduction in the excitation current, that is, the limitation on the amount of electricity generated (7), does not lead to drawbacks such as insufficient charging of the storage battery.

[Brief explanation of the drawing]

FIG. 1 is a schematic electric circuit diagram showing the configuration of an embodiment of a vehicle charging device according to the present invention, and FIG. 2 is a generator drive torque characteristic diagram for explaining the present invention in detail. ■...engine, 3...generator, 4...pulley,
5... Generator drive bell 1-16... Engine ignition switch detected! , 20, 21...F/V
converter. 22.23... Comparator, 28... Duty controller. 16... Excitation current switching element, 17... Switching control element, 19... Flywheel diode, 24... Voltage control function section, 7... Excitation coil. Representative Patent Attorney Takashi Okabe (8)

Claims (1)

[Claims] A vehicle charging device characterized in that it is provided with means for detecting a slip of a generator drive belt, and also provided with an excitation force control means for weakening the excitation of a field pole to reduce power generation when a slip occurs.