JP2851166B2 - Mixer drive - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[Object of the Invention]

[0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mixer driving device for stirring or grinding a material by, for example, rotating a drum in which two or more materials are supplied.

[0003]

2. Description of the Related Art FIG. 3 shows an example of a conventional mixer driving device.
Wherein 1 is a converter whose input side is connected to a commercial power supply and whose conduction timing of an internal control rectifier is controlled to obtain a power source of a required output voltage and frequency, and 2 is an output of the converter 1 A three-phase induction motor (hereinafter, referred to as an electric motor) driven by a power supply and rotating the drum 3 of the mixer;
Is a speed reference circuit that outputs a reference signal of the rotation speed of the motor 2, 5 is a speed detection circuit that detects the rotation speed of the motor 2, 6 is the input of the output of the speed reference circuit 4 and the output of the speed detection circuit 5. The rotation speed of the motor 2 is
Is a speed control device that outputs a signal for controlling the conduction timing of the control rectifying element of the converter 1 in order to control the voltage and frequency of the output power supply of the converter 1 so as to be the speed reference.

In the conventional mixer driving apparatus having the above-described structure, the output signal of the speed reference circuit 4 controls the rotation speed of the electric motor 2 for driving the drum 3 of the mixer. Stir or grind the material.

[0005] In some cases, the mixer is stopped with the material being put in the drum, and is driven again after a certain period of time. Then, at this time, the material accumulated at the bottom in the drum may solidify during the stop and firmly adhere to the inner wall.

[0006]

However, if the drum in this state is restarted as it is, it rotates with the material adhered to a part of the inner wall.
When the adhered side turns upward from below, a large load torque is applied to the electric motor. Conversely, when the adhered side turns from top to bottom, the drum is rotated by its own weight, so that the drum rotates at a speed exceeding the speed reference. Therefore, when the drum is restarted with the material adhered to the drum in this manner, an overload current flows through the electric motor 2 each time the drum makes one revolution, and even if a speed reference is given, the motor 3
Rotation speed cannot be controlled to be constant. As a result, the protection circuit will overcurrent or excessive speed, the motor 2 is also a possibility to repeat the stop and stops, again.

An object of the present invention is to provide a mixer drive device capable of preventing the racing of the installation according Repetitive flashing stop-restart by material uneven distribution adhering to the drum inner wall.

[0008]

SUMMARY OF THE INVENTION The present invention provides a converter for converting a commercial power supply into a speed control power supply for a motor for driving a mixer, a speed reference setting means for outputting a reference for the rotation speed of the motor, and a speed reference setting means. In a mixer driving device comprising a set value of means and a rotation speed detection value of an electric motor, and a speed control means for controlling the rotation speed of the electric motor by adjusting the output of the converter, the rotation speed detection value at the start of the electric motor or determining means for detecting the presence of the motor starting current is compared with preset set value ubiquitous sticking material mixer in the drum at the difference provided, the electric motor is stopped when it is determined that there ubiquitous fixation, A mixer driving device characterized in that a normal operation is performed when it is determined that there is no uneven adhesion.

[0009]

In the mixer driving apparatus constructed as described above, whether the material in the drum is solidified and does not adhere to the inner wall of the drum is detected based on the speed or current characteristics when the motor is rotated.

According to the speed characteristic, if the material is solidified and adheres to the inner wall of the drum, the drum is rotated by its own weight when the material turns from top to bottom. Turns the motor. Therefore, if the material
In the case of turning from the top to the bottom, if there is a speed feedback of a certain bias value or more than the low speed reference, it is detected that the material is attached. Similarly, if the material turns from bottom to top
Speed velocity below a certain bias value
If there is feedback, it can detect that the material is attached.
You.

According to the characteristics of the electric current, when the material is solidified and adheres to the inner wall of the drum, the current flowing through the electric motor is higher when the material is turned upward from below than when the material is not adhered. Is detected by increasing
When the material rotates from the top to the bottom, the motor is rotated by its own weight, so that it is detected by the fact that no current flows through the motor.

[0012]

An embodiment of the present invention will be described below with reference to FIG. However, the same components as those of the conventional driving device shown in FIG.

[0013] In FIG. 1, 7, slow speed of the order to detect whether the inside of the material of the drum 3 before re driving the electric motor 2 at high speed and solidified, to rotate between at constant motor 2 at a low speed material deposition detecting speed reference circuit for a reference via a predetermined time and chopped circuit 13 outputs to the speed controller 6,
Reference numeral 8 denotes a bias circuit that outputs a bias signal. Reference numeral 9 denotes an input of an output signal of the speed reference circuit 7 for detecting material adhesion, an output signal of the bias circuit 8, and an output signal of the speed detection circuit 5, and an output of the speed detection circuit 5. When the signal is larger than the sum of the output signal of the bias circuit 8 and the output signal of the speed reference circuit 7 for material adhesion detection, the comparator outputs a detection signal indicating that the material inside the drum 3 has hardened.

[0014] In the mixer drive apparatus constructed as described above, before re-driving the motor 2 at a high speed, a slow speed reference from material deposition detecting speed reference circuit 7 constant at between generation, speed detecting circuit 5 of the output signal, compares whether not greater than the sum of the output signal of the speed reference bias circuit 8 by a comparator 9, an output signal of the speed detector 5 is greater than the sum of the speed reference bias signal When this happens, a material adhesion detection signal indicating that the material has solidified and adhered to the inner wall of the drum 3 is output, input to the speed control device 6 and the electric motor 2 is stopped via the converter 1.

[0015] Conversely, the output signal of the speed detecting circuit 5, when smaller than the sum of the output signal of the speed reference and bias circuit 8, switching circuit 13 is provided instead Ri switch on the side of the speed reference circuit 4 a predetermined speed Accelerated.

As described above, if the material is unevenly attached to the inner wall of the drum, when the attached material rotates from top to bottom, the motor 2 rotates faster than the speed reference due to the weight of the material. The mixer driving device according to the present invention is a mixer driving device configured to detect that the material is solidified and adhered to the inner wall of the drum when the difference exceeds a certain set value.

Therefore, according to the present invention, it is possible to know whether or not the material in the drum of the mixer is solidified before re-driving the drum of the mixer, so that the motor is stopped due to overload and over-speed after re-driving. In addition, it is possible to prevent the power transmission system such as the shaft, the coupling and the reduction gear between the electric motor 2 and the drum 3 from being damaged due to the irregular rotation of the drum, and to prevent the equipment from running idle due to stop / restart.

Next, FIG. 2 shows another embodiment of the mixer driving device according to the present invention. In the figure, reference numeral 10 denotes a current detection circuit for detecting the load current of the motor 2 on the power supply side of the converter 1;
Is a comparison value setting circuit for setting a value for comparing the level of the output of the current detection circuit 10, and 12 is for detecting whether the material inside the drum 3 is solidified before the electric motor 2 is driven again. The output signal of the current detection circuit 10 for detecting the load current of the motor 2 when the speed reference is generated by the speed reference circuit 4 for a certain period and the output signal of the comparison value setting circuit 11 are input and compared. When the output signal of the detection circuit 10 is smaller than the output signal of the comparison value setting circuit 11 or is larger depending on the set value of the comparison value setting circuit 11, the comparator that outputs the material adhesion detection signal to the speed control device 6 is there.

In the mixer driving apparatus having the above-described structure, the overcurrent caused by the uneven curing of the material inside the drum 3 is detected at the input side of the converter , so that the comparison is performed similarly to the embodiment shown in FIG. The adhesion of the material is determined by the device 12, and the result is input to the speed control device 6, and the motor 2 is stopped.

In the above embodiment, the motor 3 for driving the mixer 3 is a three-phase induction motor, but may be another AC motor or a DC motor. Further, in the above embodiment, the mixer 3 has been described in example mixers stirring or pulverizing the material adhering to the inner wall to abort Then cure period rotation there is an internal material in the mixer for mixing, for example, liquid material If it does, it can be applied.

[0021]

As described above, according to the present invention, a converter for converting a commercial power supply to a speed control power supply for a motor for driving a mixer, speed reference setting means for outputting a rotation speed reference for the motor, and this speed reference setting the mixer drive system including a set value and the motor speed setting means for adjusting to controls output rotation speed of the motor output of the rotational speed detection value is input transducer means, the motor startup rotational speed detection A determination means is provided for comparing the value or the starting current of the motor with a preset value and detecting the presence or absence of unevenly fixed material in the drum of the mixer based on the difference, and when it is determined that unevenly fixed material is present, the motor is stopped. because when it is determined that the uneven distribution secured without the to perform the normal operation, to obtain a mixer drive device capable of preventing the racing of the equipment and damage of the power transmission portion of the electric motor and the mixer That.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of a mixer driving device according to the present invention.

FIG. 2 is a block diagram showing another embodiment of the mixer driving device of the present invention.

FIG. 3 is a block diagram showing one embodiment of a conventional Misaki drive device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Converter, 2 ... Electric motor, 3 ... Drum 4 ... Speed reference circuit, 5 ... Speed detection circuit, 6 ... Speed control device, 7 ... Speed reference circuit for material adhesion detection, 8 ... Bias circuit, 9 ... Comparator .

Claims (1)

(57) [Claims] A converter for converting a commercial power supply into a speed control power supply for a motor driving a mixer; speed reference setting means for outputting a rotation speed reference for the motor; setting values of the speed reference setting means and the motor; of the mixer drive system including a speed control means for rotational speed detection value is input by adjusting the output of the transducer to control the rotational speed of the electric motor, the rotational speed detection values of the startup of the motor or the motor starting current and providing a determination means for detecting the presence or absence of uneven distribution sticking material in advance by comparing the set value the mixer in the drum at the difference, it is stopped the motor in the determination of ubiquitous fixed there, uneven distribution sticking mixer drive characterized in that the normal operation so as to continue <br/> rows determination without.