JPS6120533Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an engine rotation speed determination device that uses a regulator of a generator attached to the engine to easily determine the engine rotation speed.

Conventional engine rotation speed detection was done for example in 1973.
- As disclosed in Publication No. 16784, this is done using the engine's ignition signal, but if you try to detect the engine speed in the same way in a diesel engine without an ignition system, a pick-up coil will be placed on the engine's flywheel, etc. It is necessary to install other devices such as the following, which has the disadvantage of complicating the configuration.

By the way, generators generally rotate in synchronization with the rotation of the engine. That is, the generator is driven directly from the crankshaft or indirectly via a V-belt or a continuous belt, and rotates in response to the rotation of the engine.

On the other hand, a regulator is provided to keep the generated voltage of the generator constant, and the regulator is equipped with switching means for controlling on/off the excitation current flowing through the field winding using a relay or an electronic circuit. This controls the generated voltage of the generator. The period of turning on and off this excitation current corresponds to the rotation speed of the generator, that is, the rotation speed of the engine.If the engine speed is high, the above-mentioned on-off period is short, and if the engine speed is low, the above-mentioned on-off period is becomes longer.

Therefore, it can be seen that by determining whether the cycle of turning on and off the excitation current by the switching means is less than or equal to a certain value, it is possible to determine whether or not the engine speed is greater than or equal to a predetermined value.

This invention was made in view of the above points, and by extracting the on/off signal of the switching means of the regulator and determining parameters corresponding to the period such as the period or pulse width of the pulse signal, It is an object of the present invention to provide an engine rotation speed determination device that determines whether the engine rotation speed is equal to or higher than a certain value.

Embodiments of this invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 shows a relay type regulator equipped with an engine speed determination device according to an embodiment of this invention. In the figure, 1 is a generator that rotates in synchronization with the rotation of the engine. A child winding 2, a field winding 3 that is excited according to the on/off cycle of a constant voltage relay 7 of a regulator 5, which will be described later, and a diode circuit 4 that rectifies the induced electromotive force of the armature winding 2. It's summery.

Reference numeral 5 denotes a regulator that controls the generated voltage of the generator 1, and when a voltage approximately half of the generated voltage appears at the output terminal 1a of the generator 1, the regulator 5 moves its relay contact 6a from the illustrated position to the right side. Charge lamp relay 6, generator 1 to be moved to
It consists of a constant voltage relay 7 and resistors 8, 9, and 10, which move the relay contact 7a from the illustrated position to the left when a generated voltage appears at the output terminal 1b of the .

Also, 11 is the battery, 12 is the key switch, 1
3 is a charge lamp. Reference numeral 14 denotes an engine rotation speed determination device according to this invention, and the device 14
is the contact 7 of the constant voltage relay 7 of the regulator 5.
The relay 17 is connected to a terminal 15 connected to a terminal 15 via a resistor 16 and operates a relay contact 17a by the current flowing through it.The coil of this relay 17 has a field winding, for example. A coil may be used that turns on the relay contact 17a when 12V, which is the voltage applied to the wire 3, is applied for a certain period of time. And 18 is an actuating device operated by opening and closing this relay contact 17a,
The actuating device 18 includes, for example, an idler control lever that operates the control lever of the fuel injection pump to the fuel increase side to maintain the engine speed at a predetermined speed when the engine speed falls below the normal idle speed. A power-up device can be considered.

Next, the operation will be explained.

First, when the key switch 12 is turned on, the engine is not rotating at first, so the generator 1 does not output power to either the output terminals 1a or 1b, and the power is sent from the battery 11 via the key switch 12 to the charge lamp 13 and the relay. Current flows through the contact 6a and the ground path, and also passes through the key switch 12 to the relay contact 7a, field winding 3,
Current flows through the ground path, and the charge lamp 13
lights up. When the engine rotates, the armature winding 2 of the generator 1 rotates, the field winding 3 is excited as described above, and the generator 1 generates a power output at the output terminals 1a and 1b. relay 6
A current flows to move the relay contact 6a to the right from the state shown in the figure, thereby breaking the circuit of the charge lamp 13 and turning off the charge lamp 13.

Next, during low-speed operation, when the power generation output of the generator 1 becomes too large, current flows from the output terminal 1b to the constant voltage relay 7, and the relay contact 7a moves to the left from the state shown in the figure, and from the contact 7a ₁ Then, a resistor 8 is inserted in the circuit from the battery 11 to the field winding 3, and the excitation current of the field winding 3 is weakened. As a result, when the power generation output decreases, the current flowing through the constant voltage relay 7 decreases, the relay contact 7a moves to the right in the figure and comes into contact with the contact _7a1 , and the exciting current to the field winding 3 increases. Power output increases again.

In addition, during high-speed operation, when the generated output of the generator 1 becomes too large, current flows from the output terminal 1b to the constant voltage relay 7, and the relay contact 7a moves to the left and is crimped with the contact 7a ₂ , causing the field The current to winding 7 is cut off. As a result, when the power generation output decreases, the current flowing through the constant voltage relay 7 decreases, the relay contact 7a contacts the contact _7a1 , the exciting current to the field winding 3 increases, and the power generation output increases again.

In this way, in the regulator 5, the constant voltage relay 7 and the relay contact 7a act as switching means to control the generated voltage of the generator 1, and the on/off period of the relay contact 7a is determined by the engine rotation speed. Correspondingly, as the engine speed increases, the above-mentioned on/off cycle becomes shorter.

In the above operation, relay contact 7a
The voltage at the terminal 15 connected to the engine speed is detected as a current flowing through the engine speed determining coil 17 via the resistor 16, and this current is detected as an opening/closing signal of the relay contact 17a. Therefore, if the actuating device 18 is configured to be activated depending on whether a parameter corresponding to the period or the pulse width of the opening/closing signal is equal to or greater than a certain value, for example, the idle-up device 18 can be activated when the engine speed is at idle speed. When the engine speed is lower than the idle speed, the control lever of the fuel injection pump is operated to increase the amount of fuel, and the engine speed is maintained at the idle speed.

Figure 2 shows another embodiment of this invention, which is
This idea is applied to an IC regulator.

In the figure, the same reference numerals as in FIG.
Both resistors 2 are connected via the Zener diode 22.
A first transistor 23 that is controlled on and off by a divided voltage of 0 and 21, a collector resistor 24 of this transistor 23, and the transistor 23
It consists of a second transistor 25 whose on/off is controlled by a transistor 25, and a diode 26 connected to the collector of this transistor 25.

The engine speed determination device 14 of the present invention extracts the base signal of the second transistor 25, and determines whether the period of the on/off signal or the parameter corresponding to the period such as the pulse width is equal to or greater than a certain value. It is configured to determine whether the engine speed is equal to or higher than a predetermined value and output a determination output 27.

Next, the operation will be explained.

First, when the key switch 12 is turned on, since the generator 1 is not generating power at first, the battery 11 is connected to the key switch 12, the charge lamp 13, the field winding 3, and the second transistor 2 of the regulator 5.
5. Current flows through the ground path and the charge lamp 13 lights up. When the armature winding 2 rotates due to the rotation of the engine and current flows through the field winding 3 as described above, the generator 1 outputs a power generation output to the output terminals 1a and 1b, and the charge lamp 13 is turned off.
Also, if the power generation output of generator 1 becomes too large,
The divided voltage by the resistors 20 and 21 also increases, the first transistor 23 is turned on via the Zener diode 22, the second transistor 25 is turned off, and the excitation current to the field winding 3 is cut off. , the power generation output is weakened. When the power generation output is weakened, the voltage divided by the resistors 20 and 21 becomes smaller, the first transistor 23 is turned off, the second transistor 25 is turned on, and the field winding 3
The excitation current flows again to increase the power generation output.

In this way, this regulator 5 switches the field winding 3 by switching the transistors 23 and 25.
The power generation output is controlled at a constant level by turning on and off the excitation circuit, but the on/off period of the excitation circuit corresponds to the engine speed, and as the engine speed increases, the excitation circuit's output increases. The on/off cycle becomes shorter. Therefore, the engine rotation speed determination device 14 according to the present invention detects the transistor 25.
By extracting the base on/off signal and determining whether its period or pulse width is greater than a certain value, it is possible to determine whether the rotational speed is greater than a certain value.

Note that this invention is not limited to the above-mentioned embodiment, and the internal configuration of the engine speed determination device is such that the pulse period or pulse width of the input on/off signal is compared with a certain reference value and a predetermined value is determined. It may be configured to output a binary output indicating whether or not the engine rotation speed is higher than or equal to the engine speed, and use this to operate an external actuating device.

Also, the objects to be controlled by the output of the discriminator are:
In addition to the above-mentioned idle-up device, a device for controlling secondary air, an exhaust gas purification device such as an exhaust gas circulation device, etc. can be considered.

As described above, according to this invention, the on/off signal of the switching means of the regulator that controls the excitation current of the generator driven by the engine is input, and the period of the input signal or the period of the pulse width etc. By determining whether the corresponding parameter is above or below a certain value, it is determined whether the engine speed is above a certain value, so it is very easy to use, especially in engines without an ignition system such as diesel engines. This configuration has the effect of making it possible to easily determine the engine speed.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of an engine speed determination device according to one embodiment of this invention, and FIG. 2 is a circuit diagram of another embodiment of this invention. DESCRIPTION OF SYMBOLS 1... Generator, 3... Excitation coil, 5... Regulator, 7... Constant voltage relay as switching means of the regulator, 23, 25... Transistor as switching means of the regulator.

Claims (1)

[Scope of utility model registration request] To determine whether the period of the input signal or a parameter corresponding thereto is greater than a certain value by inputting an on/off signal of a switching means of a regulator that controls the excitation current of a generator driven by an engine. An engine rotation speed determination device characterized in that it is determined whether the engine rotation speed is equal to or higher than a certain value.