JPS5933875Y2 - engine generator - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an engine generator that can operate an engine efficiently and smoothly at no load, at load, and at startup.

Conventionally, the engine speed in engine generators is maintained at a constant high speed determined by the frequency of the generator's rated output (50Hz, 60Hz), so the noise is intense both at no load and under load, especially at no load. The high speed rotation of the engine not only unnecessarily reduces the durability of the engine, but also reduces fuel efficiency, which impairs the economic efficiency of the engine generator.

However, as a countermeasure to this problem, for example, if the engine speed at no-load is reduced regardless of the frequency of the generator's rated output, the engine rotation will be unstable at cold start and the engine will stop during warm-up. It had the disadvantage of being easy.

The purpose of this invention is to automatically reduce the engine speed when there is no load, and when starting the engine from a cold state, until the engine reaches a certain warm-up state.
The object of the present invention is to eliminate the drawbacks of the prior art by providing an engine generator that operates the engine at high speed.

Next, the configuration of an embodiment of the present invention will be explained with reference to the drawings.

A generator 3 with a field coil CF wound around the rotor 1 and an armature coil CA wound around the stator 2 is driven by the engine 4, and the engine 4 rotational speed is controlled by a centrifugal governor and a tension spring 5 installed inside the engine 4. The frequency of generator 3 rated output (50Hz, 60H
An electromagnetic solenoid SQL is attached to the engine generator 6 that maintains the rotation speed at a constant high speed corresponding to When the electromagnetic solenoid SQL is not energized, the throttle valve 11 of the carburetor 10 is controlled by the action of the centrifugal valve, so the engine 4 rotation speed is maintained at a constant high speed rotation corresponding to the frequency of the rated output of the generator 3. Furthermore, when the electromagnetic solenoid SQL is excited, the throttle valve 11 of the carburetor 10 is fixed in the semi-closed state via the connecting rod 8 and the engine adjustment lever 9, so the engine 4 rotation speed is the frequency of the generator 3 rated output. It is held at low speed rotation regardless of the

Further, the engine 4 is provided with a contact that switches the contact from on to off when the temperature of the engine 4 reaches a preset temperature, that is, a temperature at which the engine 4 will not rotate unstablely and stop during the low speed rotation. A temperature-sensitive reed switch TLS is installed.

Next, FIG. 2 is an electric circuit diagram of this embodiment, in which the armature coil CA of the stator 2 is connected to the AC side terminal of the full-wave rectifier mD1, the primary coil N1 of the current transformer CT, and the no-fuse breaker NFB. The lighting coil 13 attached to the engine 4 is connected to the AC side terminal of the full-wave rectifier S D1 (7), and the DC side terminal of the full-wave rectifier SDI is connected to the load connection outlet 12 through the is connected to the field coil CF of the rotor 1 via a slip ring 14.

Further, the full-wave rectifier SD2 connected between the output terminals of the stator 2 via the full-wave rectifier SD1 includes a slow-down circuit that controls on/off the electromagnetic solenoid SQL by the output of the current transformer CT, that is, a current transformer. secondary coil N2 of the device CT,
Diode DI, capacitor +jC1, resistors R1, R2,
Electromagnetic solenoid SQL and transistor T r 1 sT
A slowdown circuit 15 is connected to the electromagnetic solenoid SQL, and a temperature-sensitive reed switch TLS is connected between the base and emitter of the transistor Tr2 connected in series with the electromagnetic solenoid SQL. is forming.

In addition, vl is a voltmeter for detecting the output voltage of the generator 3, and PLI
is the pilot lamp for checking the operating status of generator 3, SWl
is the slowdown release selector switch connected in series with the electromagnetic solenoid SQL, and the full-wave rectifier 5D30 circuit shown by the dotted line in Figure 2 has a generator 3 rated frequency of 50H.
The circuit shown by the dashed line in FIG. 2 shows the connection when the rated frequency of the generator 3 is 60 Hz.

Next, the operation of this embodiment will be explained.

First, the power generation principle of the generator 30 will be explained using the simplified circuits shown in FIGS. 3 to 5. As shown in FIG. 4, the engine 4
When the engine 4 is rotated, alternating current power is generated from the lighting coil 13 built into the engine 4, and the same power is transmitted to the fourth
As shown by the arrow in the figure, the electric current is supplied to the field coil CF of the rotor 1 via the full-wave rectifier SDI and the slip ring 14.

Therefore, when the load 11 is connected to the outlet 12 while the field coil CF is excited, the load current passes through both the armature coil CA and the field coil CF in series as shown by the arrow in FIG. , the voltage generated from the armature CA increases due to an increase in the field coil CF excitation current due to an increase in the load current, and a decrease in the output voltage of the generator 3 due to an increase in the load 17 is prevented.

Next, to explain the slowdown that lowers the rotation speed of the engine 4 when there is no load, firstly, when there is no load, the output of the current transformer CT is extremely small, so the transistor T
rl is off, transistor Tr2 is turned on, and the electromagnetic solenoid SQL is excited. As a result, the throttle valve 11 of the carburetor 10 is fixed in the semi-closed state via the connecting rod 8 and the engine adjustment lever 9, and the engine speed is 4. The throttle valve 110 is maintained at a constant low rotation speed corresponding to the half-closed state, and the output of the generator 3 is reduced, but since it is in a no-load state, there is no electrical effect, and on the contrary, the noise is reduced due to the decrease in engine rotation speed. This has the effect of reducing noise pollution to the surrounding area, improving the durability of the engine 4, and reducing fuel consumption of the engine 4.

Next, when the load 11 is connected to the outlet 12 in the slowdown state of the engine 4 at low speed, the electromagnetic solenoid SQL becomes de-energized due to the transistor Tr1 being turned on and the transistor Tr2 being turned off due to the increase in the output of the current transformer CT. The fixation of the throttle valve 11 by the solenoid SQL is released, and the throttle valve 11 is controlled by the original centrifugal governor, and the engine 4 rotation speed is kept at a constant high speed corresponding to the frequency of the generator 3 rated output regardless of the size of the load 11. The rotation speed is maintained.

Next, to explain the slowdown release that operates when the engine 4 is started at a low temperature, the engine 4 is started in a low temperature state where the engine 4 has not been properly warmed up, and in this starting state, the slowdown is activated and the engine rotates four times. If the number is low, the engine 4 will not stabilize at 4 revolutions because the slow speed is generally set as low as possible, and the engine 4 may stop before it is warmed up.

Therefore, in the case of this embodiment, since the temperature-sensitive reed switch TLS is in the ON state when the engine 4 is not properly warmed up and is in a low temperature state, when the engine 4 is started in this low temperature and no-load state, the output of the current transformer CT is Even if the transistor Tri is off, the base and emitter of the transistor Tr2 are short-circuited by the temperature-sensitive reed switch TLS, so the transistor Tr2 is off and the electromagnetic solenoid SQL is also off.

Even in a no-load state, the slowdown does not operate, and the engine 4 rotates at a constant high speed set by the centrifugal governor.

When warm-up is finished in this state and the temperature of the engine 4 becomes high, the temperature-sensitive reed switch TLS is turned off, and since the transistor Tri is in the off state, the transistor Tr2 is turned off.
is turned on, the electromagnetic solenoid SQL is energized.

As a result, the engine 4 is controlled by the slowdown circuit 15 and kept at a low rotation speed when no load is applied, and is automatically maintained at a constant high rotation speed corresponding to the frequency of the rated output of the generator 3 when the engine 4 is loaded. .

Note that if the temperature of the engine 4 is high and the temperature-sensitive reed switch TLS is off at the time of starting, the engine 4 is slowed down by the slowdown circuit 15 from the time of starting.

Next, the effects of the present invention will be explained.

In this invention, a rotor wrapped with a field coil is connected to the engine crankshaft, and a stator wrapped with an armature coil is connected in series with a current transformer used as a load current detection block and the AC side terminal of a full-wave rectifier. The lighting coil attached to the engine is connected to the AC side terminal of the full wave rectifier through a slip ring, and the field coil of the rotor is connected to the DC side terminal of the full wave rectifier through a slip ring. Connect to the terminal,
A temperature sensing element is installed on the engine body as a temperature sensor that changes the output signal at a corresponding temperature after the end of warm-up, and an electromagnetic solenoid for engine slowdown control is installed when no load is applied from the current transformer. A slowdown circuit is provided that is turned on by the output and turned off by the load output, and further, when the output signal from the temperature sensing element is an output signal of a temperature corresponding to the temperature before the end of the warm-up operation, the slowdown circuit is turned on by the output. The engine generator is further provided with a slowdown release circuit that turns off the electromagnetic solenoid with priority over the slowdown circuit.

Accordingly, the present invention adds a temperature sensing element as a slowdown release circuit to the slowdown circuit that controls the slowdown control electromagnetic solenoid on and off according to the change in output from the current transformer during no-load and under load. By sharing the slowdown circuit and electromagnetic solenoid for no-load slowdown control, the slowdown release control at cold start is simplified and easily performed, and the low-temperature start characteristics of engine generators and no-load/load It has the effect of reducing the production cost of engine generators while improving slowdown switching performance, as well as automatically lowering the engine speed during no-load conditions and starting the engine from a cold state. In this case, the engine is operated at high speed until the engine reaches a certain warm-up state, and the engine generator is started smoothly and can be operated economically.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a road body according to an embodiment of the present invention, FIG. 2 is an electric circuit diagram thereof, and FIGS. 3 to 5 are simplified circuit diagrams thereof. 1... Rotor, 2... Stator, 3...
... Generator, 4 ... Engine 6 ...
・・Engine generator, 13・°・・・・Lighting coil, 1
4... Slip ring, 15... Slowdown circuit, 16... Slowdown release circuit, CF... Field coil, CA...・Armature coil, CT...Current transformer, SDI...
・Full wave rectifier, TLS... Temperature sensitive reed switch, SQL... Electromagnetic solenoid.

Claims (1)

[Scope of utility model registration request] A circuit is constructed in which a rotor wrapped with a field coil is connected to the engine crankshaft, a stator wrapped with an armature coil is connected in series with a current transformer as a sensor for detecting load current, and the AC side terminal of a full-wave rectifier. A lighting coil attached to the engine is connected to the AC side terminal of the full wave rectifier, and a field coil of the rotor is connected to the DC side terminal of the full wave rectifier via a slit ring. A temperature sensing element is installed on the engine body as a temperature sensor that changes the output signal at a corresponding temperature after the end of warm-up, and an electromagnetic solenoid for engine slowdown control is installed when no load is applied from the current transformer. A slowdown circuit is provided that is turned on by the output and turned off by the load output, and further, when the output signal from the temperature sensing element is an output signal of a temperature corresponding to the temperature before the end of the warm-up operation, the slowdown circuit is turned on by the output. An engine generator comprising: a slowdown release circuit that turns off the electromagnetic solenoid with priority over the slowdown circuit.