JP2000184795A - Slowdown device for engine driven ac generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a slowdown device free from troubles even in the case of the careless operation of slowdown switch while power is being supplied to a load. SOLUTION: This slowdown device for an engine driven AC generator excites a solenoid 5 by operating a slowdown switch 12, and lowers the engine speed by actuating a governor lever 3. A normally closed contact 20 interlocked with a no-fuse breaker 7 is formed between the power relay 11 energizing the solenoid 5 and the slowdown switch 12, or a normally closed contact 21a interlocked with the slowdown switch is connected with the power circuit of an automatic voltage regulator 22. Therefore, when the no-fuse breaker 7 is on, the governor lever 3 is not actuated even in the case of the accidental operation of the slowdown switch 12, or, if the slowdown switch is operated, the generated voltage of a generator 1 is made zero.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a slowdown device for an engine-driven AC generator.

[0002]

2. Description of the Related Art The engine of an engine-driven alternator is
When operating under load, it is necessary to operate at a predetermined high speed corresponding to the rated frequency of the alternator, but when there is no load, the engine is rotated at low speed (slow down) to save fuel consumption. And noise reduction. A slowdown device generally used in the related art will be described with reference to FIG.

The engine 1 is connected to a generator 2 by a coupling 6, and the output of the generator 2 is connected to a load 8 such as a motor via a no-fuse breaker 7. The governor lever 3 of the engine 1 is always attracted by the spring 4 and is positioned on the high-speed rotation side. When the electromagnetic solenoid 5 is excited, the governor lever 3 is attracted to the position on the low-speed rotation side (dotted line in FIG. 4). ), The output speed of the engine is low (idling). The electromagnetic solenoid 5 operates via the power relay 11 by operating the slow down switch 12.

When the engine is started, a timer 13 and a normally closed contact 18 are provided so as to be in an idling state for a predetermined time so as to excite the electromagnetic solenoid 5.
When the temperature of the engine cooling water is equal to or higher than 50 ° C., a water temperature switch 16 and a normally closed contact 17 of the relay 14 are provided in order to immediately perform high-speed operation when the engine is started. .

[0005]

However, in such a conventional slowdown device, the slowdown switch is operated while monitoring the load condition, and this is not possible when the engine is supplying power to the load at the rated speed. When the slowdown switch is operated easily, a load such as a generator or a motor may be burned.

Incidentally, without providing a slow down switch,
A current transformer is provided on the output bus of the generator to automatically rotate the engine at low speed when there is no load current.However, since this device is expensive, the use condition of the load is intermittent. It is used in special cases, such as

SUMMARY OF THE INVENTION It is an object of the present invention to provide a slow-down device which does not cause a problem even if a slow-down switch is operated carelessly when power is supplied to a load.

[0008]

The present invention employs the following means to achieve the above object. That is, the slowdown device for an engine-driven alternator according to the first aspect of the present invention provides a slowdown device for an engine-driven alternator that excites an electromagnetic solenoid by operating a slowdown switch and operates a governor lever to reduce the engine speed. In the down device, a normally closed contact interlocking with a no-fuse breaker provided on the output side of the generator is provided between a power relay for energizing the electromagnetic solenoid and a slow down switch, and when the no-fuse breaker is turned on, The feature is that the governor lever is not activated by the operation of the slow down switch.

The present invention is applied to an engine-driven AC generator having a slow-down device that operates a governor lever by operating a slow-down switch to idle the engine, and a current transformer on the output side of the generator. Is not targeted for detecting no load.

The governor lever is always located on the high-speed rotation side by a spring, and is operated to the low-speed rotation side by exciting the electromagnetic solenoid. The slow-down switch is connected to a power relay that energizes the electromagnetic solenoid, and a normally closed contact between this power relay and the slow-down switch that is linked to the opening and closing of a no-fuse breaker provided on the output side of the generator Is provided.

Therefore, when power is supplied to the load, the power relay does not operate even if the slowdown switch is operated, and the governor lever remains at the high-speed rotation side. Absent. When slowing down, it is necessary to shut off the no-fuse breaker after checking the load condition.

The engine-driven AC generator is generally provided with a mechanism for idling for a predetermined time (for example, 30 seconds) when the temperature of the cooling water of the engine is low, and this mechanism is operated by a no-fuse breaker. It may or may not be linked to opening and closing.

According to a second aspect of the present invention, there is provided a slow-down device for an engine-driven alternator which operates an slow-down switch to excite an electromagnetic solenoid to operate a governor lever to reduce the engine speed. In the slow down device, a normally closed contact linked to the slow down switch is connected to a power supply circuit of the automatic voltage regulator, and when the slow down switch is operated,
It is characterized in that the voltage generated by the generator is set to zero.

The engine-driven alternator is provided with an automatic voltage regulator for keeping the output voltage constant with respect to fluctuations in the load of a motor or the like. The slow down switch is provided in the power supply circuit of the power relay for energizing the electromagnetic solenoid similarly to the first aspect of the present invention, and a normally closed contact linked to opening and closing of the slow down switch is connected to the power supply of the automatic voltage regulator. Connected to the circuit (usually connected to the engine starter switch). With this configuration, when the slow down switch is operated, the electromagnetic solenoid is excited regardless of the presence or absence of a load, and the governor lever is operated to the low speed rotation side.

However, when the slow down switch is operated, the power supply of the automatic voltage regulator is cut off.
The output voltage of the generator becomes zero.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on an embodiment shown in the drawings. The invention described in claim 1 is the one shown in FIG.
As shown in the figure, the basic configuration is the same
And the generator 2 are connected by a coupling 6, and the load 8 is connected via a no-fuse breaker 7. The circuit of the electromagnetic solenoid 5 for operating the governor lever 3 is connected from the alternator of the engine 1 to the electromagnetic solenoid 5 via the power relay 11 and the slow down switch 12, and the slow down switch 12 and the power relay 1
1, an auxiliary contact 20 of the no-fuse breaker 7 is provided.

The auxiliary contact 20 is a normally closed contact and is in an OFF state when the no-fuse breaker 7 is turned on. When the engine is started, the electromagnetic solenoid 5 is energized for a predetermined time (30 seconds) to bring it into an idling state as in the prior art.
8 is connected to the power relay 11 in parallel with the circuit of the slowdown switch 12, and further provided with a water temperature switch 16 and a normally closed contact 17 of the relay 14, so that when the temperature of the engine cooling water is 50 ° C. or more, When the engine is started, high-speed driving is performed immediately.

With this configuration, when the no-fuse breaker 7 is not turned on, the auxiliary contact 2
When the slowdown switch 12 is operated at this time, the power relay 11 energizes the electromagnetic solenoid 5 to pull the governor lever 3 and slow down.

When the engine is started, the water temperature is 50
If the temperature is not more than 0 ° C., the normally closed contact 17 is turned on for the time set by the timer 13, for example, 30 seconds, and the power
1 operates to excite the electromagnetic solenoid 5 to the low-speed rotation side (idling). When the temperature is 50 ° C. or more, the water temperature switch 16 is turned on and the normally closed contact 17 is turned off, so that the governor lever 3 is positioned at the high-speed operation side. Will remain
It is immediately driven at high speed.

On the other hand, when the no-fuse breaker 7 is turned on, the auxiliary contact 20 is OFF, so that even if the slow down switch 12 is operated, the electromagnetic solenoid 5 is not excited and does not slow down. The same operation as above is performed when the engine is started. Therefore, when slowing down, the no-fuse breaker must be cut off after checking the load condition.

Next, another embodiment of the present invention will be described with reference to FIG. The basic configuration is the same as that of the above embodiment, and the engine 1 and the generator 2 are connected by a coupling 6, and the load 8 is connected via a no-fuse breaker 7. The circuit of the electromagnetic solenoid 5 for operating the governor lever 3 is connected to the electromagnetic solenoid 5 from the alternator of the engine 1 via the power relay 11 and the slow down switch 12, and the no-fuse is provided between the slow down switch 12 and the power relay 11. An auxiliary contact 20 (normally closed contact) of the breaker 7 is provided.

When the engine is started, as in the prior art,
In order to energize the electromagnetic solenoid 5 for a predetermined time (30 seconds) and bring it into an idling state, the normally closed contact 18 of the timer 13 is connected to the auxiliary contact 20 in parallel with the circuit of the slowdown switch 12, and further connected to the water temperature switch 16. A normally closed contact 17 of the relay 14 is provided so that when the temperature of the engine cooling water is 50 ° C. or higher, high-speed operation can be performed immediately when the engine is started. With this configuration, when the no-fuse breaker 7 is not turned on, the auxiliary contact 20 is ON,
The operation is the same as in the above case.

That is, when the slow down switch 12 is operated, the power is supplied to the electromagnetic solenoid 5 by the power relay 11, and the governor lever 3 is pulled in and slowed down.
When the engine is started, if the water temperature is 50 ° C. or less, the normally closed contact 17 is turned on for the time set by the timer 13, for example, 30 seconds, and the power relay 11 is operated to excite the electromagnetic solenoid 5, and Rotating side, 50 ℃
In the above case, the water temperature switch 16 is turned on and the normally closed contact 17 is turned off, so that high-speed operation is performed.

On the other hand, when the no-fuse breaker 7 is turned on, the auxiliary contact 20 is OFF, so that even if the slow down switch 12 is operated, the electromagnetic solenoid 5 is not excited and does not slow down. Even when the engine is started, high-speed operation is performed. That is, unless the no-fuse breaker 7 is shut off, it cannot be slowed down.

Next, an embodiment of the present invention will be described with reference to FIG. The basic configuration is the same as that of the above embodiment, 1 is an engine, 2 is a generator, connected by a coupling 6, and a load 8 is connected via a no-fuse breaker 7.

The circuit of the electromagnetic solenoid 5 for operating the governor lever 3 is connected to the electromagnetic solenoid 5 from the alternator of the engine 1 via the power relay 11 and the slow down switch 21. The slow down switch 21 has a normally closed contact 21a. And is connected to a circuit connecting the starter switch of the engine 1 and the automatic voltage regulator 22. The normally closed contact 21a is turned off when the slowdown switch 21 is operated. The automatic voltage regulator 22 is a device for keeping the output voltage of the generator constant, and when the power is turned off, the voltage generated by the generator becomes zero.

At the time of starting the engine, as in the prior art,
A timer 13 and a normally closed contact 18 are connected to the power relay 11 in parallel with the circuit of the slowdown switch 12 in order to energize the electromagnetic solenoid 5 for a predetermined time (30 seconds) to bring the solenoid 5 into an idling state. Fourteen normally closed contacts 17 are provided so that when the temperature of the engine cooling water is 50 ° C. or higher, high-speed operation can be performed immediately when the engine is started.

With this configuration, when the slow down switch 21 is operated, the power is supplied to the electromagnetic solenoid 5 by the power relay 11, and the governor lever 3 is pulled in and slowed down. At the time of starting the engine, when the water temperature is 50 ° C. or lower, the normally closed contact 17 is turned on for a time set by the timer 13, for example, 30 seconds, and the power relay 11 is operated to energize the electromagnetic solenoid 5 to reduce the speed. When the temperature is higher than 50 ° C., the water temperature switch 16 is turned on and the normally closed contact 17 is turned off, so that the governor lever 3 remains at the high speed operation side.
When the slow-down switch 21 is operated, the normally closed contact 21a is turned off, so that the power supply of the automatic voltage regulator 22 is cut off, and the output voltage from the generator 2 becomes zero. That is, regardless of whether the no-fuse breaker 7 is turned on or not, when the slow-down switch 21 is operated, the output voltage of the generator becomes zero.

[0029]

As described above, according to the first aspect of the present invention, when the no-fuse breaker of the generator is turned on, the solenoid is not energized even if the slow down switch is operated carelessly. Since the governor lever remains at the high-speed rotation side, the load of the generator and the motor does not burn out, and the original purpose of slowdown can be achieved.

In the second aspect of the present invention, when the slowdown switch is operated, the engine is slowed down, but the power supply of the automatic voltage regulator is cut off. The load of the machine and motor will not be burned. In the conventional slowdown device, power is supplied to the load side even though the output is small even during slowdown.However, in this device, since the generator output becomes zero, an unexpected accident such as electric shock may occur on the load side. Can also be avoided.

[Brief description of the drawings]

FIG. 1 is a circuit diagram of a slowdown device of an engine generator according to one embodiment of the present invention.

FIG. 2 is a circuit diagram of a slowdown device of an engine generator as another embodiment.

FIG. 3 is a circuit diagram of a slowdown device for an engine generator as one embodiment of the second embodiment.

FIG. 4 is a circuit diagram of a conventional slowdown device for an engine generator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Engine 2 ... Generator 3 ... Governor lever 4 ... Spring 5 ... Electromagnetic solenoid 6 ... Coupling 7 ... No fuse breaker 8 ... Load 11 ... Power relay 12 ... Slow down switch 13 ... Timer 14 ... Relay 16 ... Temperature switch 17 ... normally closed contact 18 ... normally closed contact 20 ... normally closed contact 21 ... slowdown switch 21a ... normally closed contact 22 ... automatic voltage regulator

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5H590 AA01 AA02 AA06 AA30 CA07 CC01 CC24 DD64 EA01 EA05 FA01 FA05 FC05 FC25 GA10 HA06 HA18 JA09 JB18

Claims (2)

[Claims] In a slow-down device for an engine-driven AC generator, which operates an slow-down switch to excite an electromagnetic solenoid and operate a governor lever to reduce the engine speed, a no-fuse provided on the output side of the generator. A normally closed contact interlocked with the breaker is provided between the power relay for energizing the electromagnetic solenoid and the slow down switch, and when the no-fuse breaker is turned on, the governor lever does not operate by operating the slow down switch. A slow-down device for an engine-driven alternator, characterized in that: 2. A normally-closed contact interlocked with the slow-down switch in a slow-down device of an engine-driven alternating-current generator that excites an electromagnetic solenoid by operating a slow-down switch and operates a governor lever to reduce the engine speed. Is connected to the power supply circuit of the automatic voltage regulator, and when the slow down switch is operated, the generated voltage of the generator is set to zero.