JPS605725Y2 - Brushed engine generator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an engine generator, and more particularly to a brush generator driven by an engine and equipped with an automatic voltage regulator that adjusts the output voltage when the output voltage fluctuates.

A conventional engine generator has a generator 1 as shown in FIG.
The magnitude of the voltage generated is adjusted by an automatic voltage regulator 2, and power is supplied to a load 3.

The generator 1 includes a stator 6 in which a main generating coil 4 and an auxiliary generating coil 5 are wound electrically at positions separated by 90 degrees, and a rotor 8 around which a field coil 7 is wound. There is.

Further, the automatic voltage regulator 2 controls the current flowing through the field coil 7 according to the output voltage generated in the main generating coil 4,
As a result, the output voltage is controlled.

In the figure, 12 is a power transistor, and transistor 1
3 and Darlington are connected.

18 is a Zener diode, 19 is a transistor, 11
, 15, 22.23 is a capacitor, 17 is a variable resistor, 1
4, 16, 20, 21 are resistors, 9, 24 are full wave rectifiers,
25 and 25' are brushes, and 10 is a diode, which are connected in antiparallel to the field coil 7 to give the field coil 7 a free-whaling effect with respect to the intermittent applied voltage.

If the rotor 8 is now rotationally driven by an engine or the like, a slight induced voltage will be generated in the main generating coil 4 and the auxiliary generating coil 5 due to residual magnetism remaining in the rotor 8.

Of these, the voltage generated in the auxiliary generator coil 5 is rectified by a full-wave rectifier 9.

A capacitor 11 is connected to the full-wave rectifier 9 for smoothing purposes.

The positive voltage rectified by the full-wave rectifier 9 is applied to the base of the transistor 13 via the resistor 14.

Since the transistor 13 and the power transistor 12 constitute a Darlington circuit, when a positive voltage is applied to the base of the transistor 13, the emitter-collector of the power transistor 12 is turned on together with the transistor 13.

As a result, a current flows through the full-wave rectifier 9 - field co/f Luer power transistor 12 - full-wave rectifier 9 circuit, and the current flowing through the field coil 7 generates a strong magnetic field in the rotor 8 .

Due to the excitation of the field coil 7 wound around the rotor 8 and the increase in the rotational speed of the rotor 8 by the engine, the generated voltage of the main generator coil 4 suddenly rises, and the voltage generated by the main generator coil 4 suddenly rises, causing a load such as a lighting lamp or a power tool to rise. 3 will be energized.

In this manner, when the generator 1 is operated at a constant speed by the engine, that is, when the rotor 8 is rotated at a constant speed, the rated output voltage can be obtained from the main generator coil 4.

Next, if the generated voltage of the main generating coil 4 rises above the specified voltage due to an increase in the rotational speed of the engine or a decrease in the load 3, the generated voltage detection lead connection point 4A provided on the main generating coil 4 is detected. The voltage detected from the main power generating coil 4 and rectified by the full-wave rectifier 24 also increases in accordance with the increase in the voltage generated by the main generating coil 4.

Therefore, the DC voltage at the connection point between the resistor 16 and the variable resistor 17 also rises, the Zener diode 18 becomes conductive, and the voltage between the base and emitter of the transistor 19 increases.
Since the Sumi current flows, the transistor 19 is turned on.

Thus, the base currents of the Darlington-connected transistor 13 and the power transistor 12, which had been flowing until then, are now
Due to the conduction of the transistor 19, no current flows, and the transistor 13 and the power transistor 12 turn off.
There is no conduction between the emitter of the power transistor 12 and the node 211.

For this reason, the excitation current flowing through the field coil 7 is blocked, and the voltage generated by the main generator coil 4 is reduced.

If the voltage generated by the main generating coil 4 decreases in this way, the voltage detected from the generated voltage detection lead connection point 4A also decreases, so that the voltage is supplied from the full-wave rectifier 24 to the connection point between the resistor 16 and the variable resistor 17. The voltage across the zener diode 18 also drops, and the zener diode 18 now becomes nonconducting.

As a result, the transistor 19 also turns off, and the base current flows again into the Darlington-connected transistor 13 and the power transistor 12, and the power transistor 12 returns to the on state, so that the excitation current flows into the field coil 7. As a result, the generator voltage of the main generator coil f4 also rises again.

As mentioned above, the automatic voltage regulator 2 is required in the engine generator, and the automatic voltage regulator 2 is configured to control the excitation current flowing through the field coil 7 wound around the rotor. Therefore, brushes 25 and 25' were used between the field coil 7 and the automatic voltage regulator 2 to connect their electric circuits.

Shown in Figure 11. The specific structure of a conventional generator having an electric circuit is shown in FIG.

Frame bodies 26.26' of the generator are connected by screws 27.27', and a rotating shaft 28 is pivotally supported by the frame bodies 26.26'.

A rotor 8 around which a field coil 7 is wound, a slip ring holder 30 provided with slip rings 29 and 29', and a pulley 31 are attached to the rotating shaft 28.

A stator 6 around which the main power generation coil 4 and the auxiliary power generation coil 5 are wound is fixed to the frame 26, 26'.

Further, an automatic voltage regulator 2 having a partially molded circuit, a capacitor 11, etc. are fixed to the frame 26, and brushes 25, 25, 25, 25, etc.
' is fixed.

A fan 32 is formed on the pulley 31.
When the generator is rotated, the fan 32 is also rotated at the same time, and the window 33 formed in the frame body 26' is forced to blow air into the interior of the generator to enhance the cooling effect.

Now, if a belt is attached to the boots 1, 1-31 and the engine is used to drive them, the rotating shaft 28 will rotate as the pulley 31 rotates, and as mentioned above, a voltage will be induced in the main generator coil 4, and power can be supplied to the load 3. can.

In this way, in conventional engine generators, the automatic voltage regulator 2 fixed to the frame body 26 controls the excitation current flowing through the field coil 7 wound around the rotor 8. A brush 25 is installed between the coil 7 and the automatic voltage regulator 2.
．． 25' and slip rings 29.29' had to be placed.

However, the current flowing into the field coil 7 passes through the full-wave rectifier 9.
The direct current is rectified by the automatic voltage regulator 2, or the direct current is interrupted by the automatic voltage regulator 2, and in either case, the polarity is in a fixed direction.

For this reason, the brushes 25, 25' are not worn out evenly, and the negative side brush is worn out more rapidly.

This is thought to be due to electrons jumping out from the negative side brush.

Therefore, in conventional engine generators, the negative side brush wears out quickly, so maintenance and inspection thereof is time-consuming.

In order to solve this problem, the present invention has an engine and
A generator driven by the engine, a main generator coil and an auxiliary generator coil wound around the stator of the generator, and a voltage induced in the auxiliary generator coil wound around the rotor of the generator is rectified. A field coil energized by the rectified output, a slip ring holder equipped with a slip ring connected to the brush and attached to the rotating shaft, and a detection voltage proportional to the voltage generated in the main generator coil generate the above voltage. A voltage regulator that controls the current flowing through the field coil and is molded inside the slip ring holder, and a first coil around which is applied a voltage proportional to the voltage generated in the main generating coil. A rotary transformer comprising a core and a second core magnetically coupled to the first core and around which a second wire is wound, the second core being provided outside the slip ring holder, and the auxiliary power generating coil. It is characterized in that a brush is connected to the motor, and this brush is connected to a full-wave rectifier that serves as a power source for an automatic voltage regulator.

The present invention provides a brushed engine generator.

An embodiment of the present invention will be described with reference to FIGS. 3, 4, and 5.

In the figure, the same reference numerals as in FIGS. 1 and 2 indicate the same parts.

35 is the first core, 36 is the first wire ring, 37 is the second core, 3
8 is a second wire ring, 39 is a tap switching means, 40.40' is a brush, 41.41' is a slip ring, 42 is a slip ring holder, 43 is an automatic voltage regulator, 44 is a base part, 45.45' is a Terminal 46 indicates an IC package forming part of the circuit of the automatic voltage regulator.

A part of the voltage generated in the main generating coil 4 of the generator is detected from the generated voltage detection lead connection point 4A and sent to the first core 35.
It is applied to the first wire ring 36 wound around.

A second core 37 is provided opposite the first core 35, and a second wire ring 38 is wound around the second core 37.

Then, the output voltage of the second coil 38 is applied by the full-wave rectifier 24, and the output voltage is applied to the resistor 16 as in FIG.
is added to the variable resistor 17.

The auxiliary generator coil 5 is also connected to the full-wave rectifier 9 of the automatic voltage regulator 43 attached to the rotating shaft 28 via brushes 40, 40'.

Brushes 40, 40' and contact slip rings 41 and 41
' is provided on a slip ring holder 42, the slip ring holder 42 is fitted onto the rotating shaft 28 by a base portion 44, and the slip ring holder 42 is firmly attached to the rotating shaft 28 by suitable means.

An automatic voltage regulator 43 is incorporated inside the slip ring holder 42.

The operation of the automatic voltage regulator 43 is similar to that of the automatic voltage regulator 2 in FIG. 1, so detailed explanation will be omitted.

The automatic voltage regulator 43 is packaged in an IC package 4 except for things such as the capacitor 11.15 and the full-wave rectifier 9.
6 can also constitute a part of an electric circuit.

FIG. 5A schematically shows the structure, and some elements such as the power transistor 12 are not shown.

The automatic voltage regulator 43 installed in this way can also be partially molded, and terminals 45, 45' are attached.

This terminal 45, 45' serves as a connection terminal to the field coil 7.

Further, on the outside of the slip ring holder 42, the above-mentioned second
A second core 37 around which a wire ring 38 is wound is attached.

Therefore, when the rotating shaft 28 rotates, the second core 37 also rotates, but the first core 35 and the second core 37
8, the first wire wheel 36 and the second wire wheel 38
The rotary transformer is constructed in such a way that a voltage related to the voltage can be obtained.

In other words, the voltage generated by the main generating coil 4 is induced in the second coil 38 regardless of the rotation speed of the rotating shaft 28.
The first core 35 and the second core 37 are magnetically coupled.

Note that since a tap switching means 39 is provided to adjust the magnitude of the excitation current to the first core 35, the second
The output voltage level of the coil 38 can be selectively controlled.

If the voltage generated by the main generator coil 4 becomes excessive, the Zener diode 18 conducts and turns off the power transistor 12, cutting off the excitation current flowing to the field coil 7 and lowering the voltage generated by the main generator coil 4. The automatic voltage regulator 43 operates in the same manner as shown in FIG.

According to the present invention, since the automatic voltage regulator 43 including the full-wave rectifier 9 and the capacitor 11 can be attached to the rotating shaft 28, a brush can be used in the current circuit to the field coil 7. There's no need.

Therefore, brushes 40, 40' can now be provided between the auxiliary generator coil 5 and the full-wave rectifier 9 for connecting the fixed electrical circuit and the electrical circuit of the moving part.

Since the current flowing between the auxiliary generator coil 5 and the full-wave rectifier 9 is alternating current and not direct current as in the conventional case, the brushes 40 and 41' are equally worn out.

Therefore, as described above, by inserting the brush into the DC circuit, it is possible to improve the drawback that the brush on the negative electrode side wears out quickly.

Moreover, since the second core 37 of the rotary transformer for applying control voltage is provided outside the slip ring holder, and the automatic voltage regulator 43 is molded inside, the entire structure can be made extremely compact, and the entire wiring can be simplified. can be easily done.

Moreover, since the automatic voltage regulator 43 is molded even if dust or dirt is attracted to it, stable operation can be achieved, so it can be used safely even in outdoor dusty places such as construction sites and roads. I can do it.

[Explanation above] [7] According to the present invention, it is possible to effectively improve the drawback that conventional brushes were inserted into the DC circuit, which resulted in significant wear and tear on the brushes, which required time-consuming maintenance and inspection. First, the rotary transformer is not for power but for control signals, so it is compact.The core of one of the rotation lances, the slip ring, the automatic voltage regulator, etc. can be integrated into one, making the whole structure compact. Moreover, it can be used safely even in places with a lot of dust.

[Brief explanation of the drawing]

1 and 2 show a conventional brushed engine generator, and FIGS. 3, 4, and 5 show a brushed engine generator according to an embodiment of the present invention. In the figure, 4 is the main generator coil, 5 is the auxiliary generator coil, 7 is the field coil, 12 is the power transistor, 18 is the Zener diode, and 35 and 37 are the first
The core and the second core, 40 and 40' are brushes, and 43 is an automatic voltage regulator, respectively.

Claims (1)

[Scope of utility model registration request] An engine, a generator driven by the engine, a main generator coil and an auxiliary generator coil wound around a fixed core of the generator, and a generator coil wound around a rotor of the generator and induced in the auxiliary generator coil. A field coil that rectifies the voltage and is energized by the rectified output, a slip ring holder that is provided with a slip ring that connects to the brush and is attached to the rotating shaft, and a detection device that is proportional to the voltage generated in the main generator coil. A voltage regulator that controls the current flowing through the field coil by voltage and is molded inside the slip ring holder, and a first wire ring to which a voltage proportional to the voltage generated in the main generating coil is applied are wound. a second core magnetically coupled to the first core and around which a second wire is wound;
A rotary transformer comprising a core and the second core provided outside the slip ring holder, a brush connected to the auxiliary power generating coil, and this brush connected to a full wave rectifier serving as a power source for an automatic voltage regulator. A brushed engine generator characterized by: