JPS6146197Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a load protection device for an engine generator, which prevents the rotational speed of the engine from being increased or decreased when a load is connected to the generator.

Generally, the power generation frequency of an engine generator changes approximately in proportion to the rotational speed of the engine. Therefore, in order to maintain a constant frequency, it is necessary to keep the engine rotation constant. Furthermore, when the frequency changes, if the load connected to the generator is an electric motor, there is a problem that the rotation speed changes, and if the load is a transformer, there is a problem such as overheating. Such a problem occurs when the engine speed is reduced to stop the engine with a load connected to the engine generator.
Therefore, in the past, a detector was installed on the output side of the generator to detect a decrease in frequency, and the signal detected by this detector opened an electromagnetic switch connected between the generator and the load. A method has been proposed in which the load is cut off from the generator when the frequency drops, but this method requires a frequency drop detector and the like, making the device expensive.

This invention was made for the purpose of improving this problem, and provides a load protection device for an engine generator that prevents the engine rotation speed from being increased or decreased while a load is connected to the generator. This is an attempt to protect the load with a simple configuration.

This invention will be described in detail below with reference to an illustrated embodiment. In the figure, reference numeral 1 denotes a main body of an engine generator, in which an engine 2 and an alternating current generator 3 driven by the engine 2 are housed. A load (not shown) can be connected to the output terminal 4 of. Reference numeral 5 denotes a load detection means, such as a solenoid, which is connected in front of the output terminal 4 of the generator 3, and is activated when the generator 3 is rotated while electricity is supplied to the output terminal 4. ing. Further, the load detecting means 5 is provided in the speed adjusting mechanism 6 of the engine 2 as follows. The speed adjustment mechanism 6 has an adjustment screw rod 7 that is interlocked with an accelerator throttle (not shown) of the engine 2. One end of the adjustment screw rod 7 protrudes from the main body 1, and the adjustment screw is moved to the adjustment position by a lock nut 11. The rod 7 can be fixed, and the protruding end of the adjustment screw rod 7 has a small diameter spline shaft 7a.
and a guide shaft 7b are formed, and a speed adjustment knob 8 is slidably inserted into the guide shaft 7b. The speed adjustment knob 8 is connected to the spline shaft 7.
The speed adjustment knob 8 has a spline boss 8a which is removably engaged with the spline shaft 7a and the spline boss 8a by means of a compression spring 9.
is biased in the direction of engagement.

On the other hand, the load detection means 5 is attached to the main body 1, and one end of a lever 10 whose intermediate part is pivoted to the main body 1 side is pivotally attached to the tip of the actuating part 5a.
The other end of the spline boss 8a of the speed adjustment knob 8 is in contact with the side surface of the spline boss 8a of the speed adjustment knob 8, and operates to separate the spline boss 8a of the speed adjustment knob 8 from the spline shaft 7a of the adjustment screw rod 7 as the speed adjustment knob 8 is operated.

Note that the operation panel may be provided with a lamp or the like that lights up when the load detection means 5 operates.

Since this device is as described in detail above, when a load is connected to the generator 3, the load detection means 5 detects this and stops the engine 2 to disable the increase/deceleration of the engine 2. To prevent the speed of the engine 2 from being carelessly lowered by the speed adjustment knob 8, such as when the engine is in use. This prevents the load connected to the generator 3 from becoming abnormally overheated due to frequency fluctuations due to a decrease in engine speed, etc., and since it is a simple device, it can be used with existing engine generators. It can be implemented easily and inexpensively.

[Brief explanation of the drawing]

The drawings show one embodiment of this invention, and FIG. 1 is a circuit diagram, FIG. 2 is a detailed view of the speed adjustment mechanism, and FIG. 3 is an explanatory view of the same operation. 2 is an engine, 3 is a generator, and 5 is a load detection means.

Claims (1)

[Scope of utility model registration request] A speed adjustment mechanism 6 that adjusts the rotational speed of the engine 2 that drives the generator 3 is removably engaged with an adjustment screw rod 7 that is interlocked with the accelerator throttle of the engine 2, and It comprises a rotating means capable of rotating the adjusting screw rod 7 when engaged, and a load detecting means 5 energized by the output of the generator 3 is provided on the output side of the generator 3,
A load protection device for an engine generator, in which the biasing force of the load detection means 5 separates the adjusting screw rod 7 from the rotating means.