JPH0125574B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an electric cooker mainly for cooking fruits, vegetables, etc.

Conventional technology Generally speaking, the rotation speed of the cutter when squeezing the fruit is approximately 5,000 rotations, so conventionally, the rotation speed of the motor was reduced using a reduction gear. but,
If a reduction gear was used, the main body would be extremely large.

Therefore, the present inventors have considered an electric cooker in which the rotational speed of the motor is controlled by an electronic circuit, and the motor and cutter are directly connected without a speed reduction device.

Hereinafter, such an electric cooker will be described using a juicer as an example with reference to the drawings.

In FIG. 5, a motor 2 whose rotational speed is controlled by an electronic circuit section 7 is provided at the inner bottom of the main body 1. The upper part of the main body 1 includes a container 5a and a container lid 5, in which a spinner 6 is rotatably provided.
b is mounted, and the drive shaft 3 of the motor 2 is connected to the spinner 6 via a coupling 4.

Problems to be Solved by the Invention However, with the above configuration, if the control device such as the electronic circuit section 7 malfunctions or breaks down for some reason, the motor 2 will not be decelerated and will remain at its original rotation speed of approximately 15,000 rpm. When the motor 2 rotates and the centrifugal force acting on the outer circumference of the spinner 6 causes problems such as destroying parts such as the container 5a or the container lid 5b, or when the rotation is locked, an overcurrent flows to the motor 2, resulting in a rare shot. There was a problem with it causing it to catch fire.

Therefore, the present invention is designed to cut off the flow of current when the motor rotates at high speed as described above, and to act as a temperature fuse when an overcurrent flows through the motor.

Means for Solving the Problems The technical means of the present invention for solving the above-mentioned problems includes a motor that rotates the cutter by controlling the number of revolutions by a control section, and a drive shaft of this motor that is not connected to the drive shaft. A leaf spring fixed in a vertical relationship, a blade portion provided on the leaf spring, and a blade portion provided within the locus of rotation of the blade portion when the rotation speed of the motor reaches a rotation speed higher than the rotation speed to be controlled. It has a winding and a wire connected in series, and the wire is made of silver or copper and has a diameter of 0.2 to 0.3 mm.
That is.

Effect The effect of this technical means is as follows.

In other words, during normal rotation, where the motor rotation is normally controlled, the blade section will only be slightly displaced.
It doesn't even touch the wires. However, if the motor rotates at high speed for some reason, the leaf spring becomes nearly horizontal due to centrifugal force, and its blade reaches the wire and cuts it. Therefore, the current is cut off and the motor stops rotating.

Additionally, if an overcurrent exceeding the rating flows through the motor, the wire made of silver wire or copper wire will melt and cut off the current if the current exceeds a certain amount, preventing motor burnout and fire. That's why.

Embodiment Hereinafter, an embodiment of the present invention will be described based on the accompanying drawings.

1 to 4, a motor 11 is held inside a main body 10, and a spinner 1 is connected to a drive shaft 12 of this motor 11 via a coupling ring 13.
4 is fitted. In addition, an insulator 1 is attached to the drive shaft 12 protruding from the frame 15 at the bottom of the motor 11.
A plate spring 17 is attached via 6. This leaf spring 17 is curved in a direction away from the frame 15, and has a blade portion 17a bent toward the frame 15 at its tip end. The optimal thickness of this leaf spring 17 is 0.1 mm to 0.2 mm; experiments have shown that if it is thicker than that, the rigidity becomes very large and it hardly deforms under the action of centrifugal force. It has been obtained. Also, if the thickness is less than that, it will be plastically deformed if a small amount of force is applied, making it useless.

On the other hand, a conductive part installation plate 18 made of a non-conductor is fixed to the lower surface of the frame 15, and the motor 1 is mounted on this plate.
Diameter 0.2mm to 0.3mm connected in series with winding 1
A wire 19 of silver wire or copper wire is stretched. Here, since the limit current value at which the motor 11 does not burn out is about 10A to 13A, it is appropriate to have a cross-sectional area that melts at about this current value, so that the diameter dimension described above is obtained.

Next, the operation of this configuration will be explained. When the drive shaft 12 rotates, the leaf spring 17 is displaced toward the frame 15 due to centrifugal force. First, motor 11
When the wire rotates normally at a reduced speed (approximately 5000 rpm), the displacement is small, and the wire 19
, and the wire 19 will not be cut. Next, if the electronic circuit section 20 or the like that controls the rotation malfunctions or breaks down, and the motor 11 is not decelerated and rotates at its original high speed (approximately 15,000 rpm), the displacement of the leaf spring 17 is large, and the leaf spring 17 is almost It has a horizontal shape, and the blade part 17a is connected to the wire 19.
Reach the position and cut it. Therefore, the current is cut off and the high speed rotation of the motor 11 is stopped.

Also, if an overcurrent flows, such as when the motor 11 is locked, a certain constant current (approximately 10 to 14 A) will be generated.
When the wire 19 flows for a certain period of time, the wire 19 acts as a temperature fuse and melts down before the motor 11 burns out, thereby preventing the motor 11 from being fired.
Experiments have shown that the optimum diameter is about 0.2 mm to 0.3 mm.

Note that although a curved leaf spring was used in the above embodiment, the leaf spring may be any type that can be deformed by centrifugal force, and is not limited to the above embodiment.

Effects of the Invention The present invention includes a plate spring mounted on the drive shaft of a motor in a non-perpendicular relation to the drive shaft, and utilizes centrifugal force during rotation to connect a silver wire or copper wire conductive to the motor windings to the plate spring. By cutting with a spring, it is possible to cut off the current, prevent high speed rotation, and ensure safety.

Further, when an overcurrent flows through the motor, the silver wire or the copper wire serves as a temperature fuse, thereby preventing burnout and ignition of the motor.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of a main part of a pump that is an embodiment of the present invention, Fig. 2 is a plan view of the pump, Fig. 3 is an enlarged sectional view of a main part of the pump, and Fig. 4 is a longitudinal cross-section of the pump. The plan view and FIG. 5 are longitudinal cross-sectional views of a conventional juicer. DESCRIPTION OF SYMBOLS 11... Motor, 12... Drive shaft, 17... Leaf spring, 17a... Blade part, 19... Wire.

Claims (1)

[Claims] 1. A motor whose rotation speed is controlled by a control unit to rotate the cutter, a leaf spring fixed to the drive shaft of this motor in a non-perpendicular relation to the drive shaft, a blade section provided on this leaf spring, and a motor that rotates the cutter at a speed exceeding a certain level. A wire is provided within the rotation locus of the blade and connected in series with the winding of the motor, and the wire is made of silver or copper and has a diameter of 0.2 to 0.3 mm. An electric cooker.