JPH0477537B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a control device for controlling the generated voltage of a vehicle charging generator.

[Conventional technology]

This type of control device (hereinafter referred to as regulator)
, two wires connected in series between the power supply and ground
Some output transistors have two output transistors, and the transistors are operated alternately depending on whether or not a charging generator is generating power, thereby selectively supplying power to a charge lamp and a choke coil as loads connected in parallel to these transistors. By the way, if the operation of the above transistors is switched at a single level, due to variations in the characteristics of the transistors, all transistors become conductive near the above level and a large current flows, resulting in damage to the transistors or sudden changes in battery voltage. Electrical components may malfunction due to low voltage.

Therefore, in order to solve the above problem, a regulator has been proposed that switches the operation of the output transistor at different levels (Japanese Patent Laid-Open No. 57-180336
issue).

[Problem that the invention seeks to solve]

However, even in the above regulator,
A similar problem may occur if the output transistor switching input signal changes rapidly.

In view of this, an object of the present invention is to provide a regulator in which the series-connected output transistors do not become conductive at the same time even if a switching input signal changes suddenly.

[Means for Solving the Problems] The configuration of a regulator R of the present invention is shown in FIG. The regulator R has a voltage control circuit 1 to control the generated voltage of the charging generator G, and has two output transistors 21 and 22 connected in series between the power supply V _IG and the ground.
1 and 22 drive the loads L1 and L2 alternately. The comparison circuit 3 compares at least one input signal Sa, which changes depending on the power generation state of the charging generator G, with a reference level V _A , and outputs "H" based on the comparison result.
A comparison signal Sb of level or "L" level is generated.

The delay circuit 4 generates a delay signal Sc that increases or decreases at a predetermined time constant in accordance with the comparison signal Sb.
The switching circuit 5 generates a signal that activates one of the transistors 21 and 22 when the delayed signal Sc is below a predetermined level _VB , and activates the transistors 21 and ₂ when the other predetermined level Vc exceeds the predetermined level VB.
It emits a signal that activates the other of 2.

[Effect]

With the above configuration, even if the input signal Sa suddenly changes, the delay signal Sc always changes with a predetermined time constant.
As a result, transistors 21 and 22 are operated at different levels V _B and Vc with a sufficient time difference so that they are not conductive at the same time.

Embodiment 1 In FIG. 2, 6 is a key switch and 7 is a battery. The charging generator G has a rotor coil G ₁ ,
It consists of a stator coil _G2 and a rectifier G3. The regulator R consists of a voltage control circuit 1, output transistors 21 and 22 connected in series between a power supply and ground, a comparator 3 constituting a comparison circuit, and a delay circuit 4 (see arrow A in Fig. 2, details shown in Fig. 3).
) and a switching circuit 5 (shown in FIG. 3).

The voltage control circuit 1 feeds back the generated voltage V _G of the generator G and controls the excitation of the rotor coil G 1 so as to maintain it at a predetermined value. An input signal Sa ₁ obtained by smoothing the voltage induced in one phase of the stator coil G 2 during power generation is input to the comparator 3 and is compared with a reference voltage V _{A 1} . Comparator 3
emits a comparison signal Sb which becomes "H" level when Sa ₁ >V _A1 and becomes "L" level when Sa ₁ <V _A1 .

The delay circuit 4 includes a constant current source 41 of output currents I ₁ and I ₂ ,
42, transistor 43 forming a current mirror circuit,
44, a switching transistor 45 and a capacitor 46, and outputs the terminal voltage of the capacitor 46 as a delayed signal Sc. That is,
When the "H" level comparison signal Sb is input, the transistor 45 is turned on and the transistors 43 and 44 are turned on.
When turned off, the capacitor 46 is charged with a constant current _I1 , and the delayed signal Sc increases at a predetermined slope. This is shown in FIG. On the other hand, when the signal Sb becomes "L" level, the transistor 45 is turned off.
Transistors 43 and 44 are turned on, and capacitor 46 is discharged with a constant current (I ₂ -I ₁ ).
As a result, the delayed signal Sc decreases at a predetermined slope (FIG. 4).

The switching circuit 5 has comparators 51, 52 and transistors 53, 54 (FIG. 2). The comparator 51 outputs an output signal Sd of "L" level when the delayed signal Sc is below a predetermined voltage _VB , and
The output transistor 21 is activated via the transistor 53 by Sd, and the charge lamp L
1 is driven. On the other hand, the comparator 52 generates an output signal Se of "H" level when the delayed signal Sc is equal to or higher than a predetermined voltage Vc higher than the voltage _VB , and the signal Se causes the output transistor 2 to pass through the transistor 54.
2 is activated, and the chiyoke coil L2 is driven. When the delay signal Sc is between the voltages V _B and Vc (times t ₁ and t ₂ in FIG. 4), neither of the signals Sd and Se is generated, and neither of the output transistors 21 and 22 is activated.

Before charging generator G starts generating electricity, Sa ₁ <V _A1
When the comparison signal Sb is at the "L" level, therefore Sc<V _B , the output transistor 21 is activated and the charge lamp L1 is lit. After the start of power generation, the signal Sa rises and when Sa ₁ >V _A1 , the comparison signal Sb becomes "H" level. As a result, the delay signal Sc starts rising at a predetermined slope, and when Sc>V _B , the output transistor 21 is turned off and the charge lamp L1 is turned off. If the signal Sc further increases and becomes Sc>Vc, the output transistor 2 will be
2 is turned on and power is supplied to the chiyoke coil L2.

After power generation stops, the signal Sa quickly decreases, and Sa ₁ <
At V _A1 , the signal Sb becomes "L" level. Delayed signal Sc
starts to fall at a predetermined slope, and when Sc<Vc, the output transistor 22 is turned off, and when Sc< _VB , the output transistor 22 is turned on, and the charge lamp L1 is lit again.

In the regulator R that operates in this manner, even if the input signal Sa ₁ suddenly changes due to noise or the like, the delayed signal Sc always changes at a predetermined slope, and therefore the transistors 21 and 22 are connected at t ₁ and t ₂ in FIG. They are switched on with a sufficient time difference between them, and are never turned on at the same time.

Embodiment 2 In FIG. 5, the comparison circuit 3 is composed of three comparators 31, 32, 33 and an AND gate 34. The feedback voltage of the generated voltage V _G is input to the comparators 32 and 33 as the input signal Sa ₂
and are compared with a reference voltage V _A2 and a reference voltage V _A3 set higher than this, respectively. The signal Sa ₁ in the above embodiment is input to the comparator 31. Comparator 31,3
When Sa ₁ >V _A1 and V _A2 <Sa ₂ <V _A3 , all signals 2 and 33 are at the "H" level, and only at this time, the comparison signal Sb output from the AND gate 34 is at the "H" level.

In other words, the signal Sb becomes "H" level only when the charging generator G starts generating power and the generated voltage V _G is within the set range, and as a result, the delayed signal
Vc rises, a signal Se is output, and the output transistor 22 is turned on instead of the output transistor 21.

In this embodiment, the signals Sa ₁ ,
Even if either Sa ₂ suddenly changes, the delay signal Sc always changes with a predetermined slope, and as in the above embodiment, the output transistors 21 and 22 are switched with a sufficient time difference and are never turned on at the same time.

〔Effect of the invention〕

As described above, the charging generator control device of the present invention compares at least one input signal that changes depending on the power generation state with the reference level set for each of these signals, and sets the control device to "H" level or high level based on the comparison result. A comparison signal of "L" level is generated, and when a delayed signal that rises or falls at a predetermined time constant according to the comparison signal is below a predetermined level, one of the transistors connected in series between the power supply and the ground is activated. In addition, when the delayed signal exceeds the predetermined level and exceeds another predetermined level, the other transistor is activated, so that even if the input signal suddenly changes, the two transistors are reliably turned on alternately and shorted. This is to prevent accidents.

Further, according to the configuration of the present invention, even if there are a plurality of input signals, only one delay circuit needs to be provided, and in this respect, the circuit becomes simple and inexpensive.

[Brief explanation of drawings]

Fig. 1 is a diagram showing the configuration of the present invention, Fig. 2 is an overall circuit diagram of a control device showing an embodiment of the invention, and Fig. 3 is a diagram showing the configuration of the present invention.
The figure is a detailed circuit diagram of part A in Figure 2, which is a circuit diagram of a delay circuit and a switching circuit, Figure 4 is a diagram showing changes over time in a comparison signal and a delay signal, and Figure 5 is a diagram showing another embodiment of the present invention. FIG. 2 is an overall circuit diagram of the control device shown in FIG. R...Regulator (control device), G...Charging generator, L1...Charge lamp (load), L2
...Chiyo coil (load), 1...Voltage control circuit, 21, 22...Output transistor, 3...Comparison circuit, 4...Delay circuit, 5...Switching circuit, 6...
...Key switch, 7...Battery.

Claims (1)

[Claims] 1 A control device that has a voltage control circuit that controls the generated voltage of the vehicle charging generator to a constant level, and has two output transistors connected in series between the power supply and the ground, and that In a charging generator control device that drives a load by alternately operating these transistors, at least one input signal that changes depending on the power generation state is compared with a reference level set for each of these signals. a comparison circuit that generates a comparison signal of "H" level or "L" level based on the result; a delay circuit that generates a delay signal that rises or falls at a predetermined time constant in accordance with the comparison signal; A control device for a vehicle charging generator, comprising: a switching circuit that generates a signal that activates one of the transistors at a level below the predetermined level, and a signal that activates the other transistor when the other predetermined level exceeds the predetermined level.