JP2006150244A - Drive control device and drive control method of crusher - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a means of saving an electric power consumption by carrying out a constant-velocity drive at a predetermined rotation number relating to the rotation number of a cage-type induction motor driving a rotary blade of a crusher in crushing a crushing material, and by carrying out a variable speed drive at a lower rotation number than the predetermined rotation number in case of not crushing the crushing material. <P>SOLUTION: The device comprises the cage-type induction motor 1 driving the rotary blade of the crusher, a current comparator 5 comparing a load current output from a load current detector 4 detecting the load current, and a setting current previously set, and a change-over controller 6 switching a rotation speed of the cage-type induction motor 1. When the variable speed drive is carried out by an inverter controller 3, if the load current is larger than the setting current, the switch to the constant-velocity drive by a constant-velocity drive controller 2 is carried out at once, and when the constant-velocity drive is carried out by the constant-velocity drive controller 2, if the load current is smaller than the setting current, the switch to the variable speed drive by the inverter controller 3 is carried out after the predetermined time to cut waste of the electric power consumption. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a drive control device and a drive control method for a pulverizer that pulverizes a material to be crushed, such as a sprue runner and a defective molded product, particularly for energy saving.

  Conventionally, this type of technology has (i) formed a supply port for the material to be crushed in the upper part of the pulverizer body, installed a rotary blade rotatably in the pulverization chamber communicating with the supply port, A fixed blade is fixed, a screen that covers the rotating blade and the lower outer periphery of the rotating blade at a position below the fixed blade is installed, and the material to be crushed supplied to the supply port is pulverized by the rotating blade and the fixed blade, and a fixed particle size The following materials to be crushed are discharged from the screen mesh, or (b) a grinding shaft having a function of being pulverized to a fine particle size in order to reuse the materials to be crushed by one pulverizer. A finish pulverizer and a coarse pulverizer equipped with a coarse pulverization shaft having a function of pulverizing to a coarse particle size in order to discard the material to be pulverized are known.

  The crushing shaft and the crushing shaft are connected to one squirrel-cage induction motor, and the crushing blades provided on the crushing shaft and the crushing shaft have different shapes.

  However, in the crusher of (i), when the material to be pulverized is to be pulverized into different particle diameters, different rotary blades must be used depending on the shape and type of the material to be pulverized. It took time and was troublesome.

  In addition, in the crusher (b), if it is desired to crush the material to be pulverized into different particle sizes, it is necessary to connect two rotary shafts, a crushing shaft and a coarse crushing shaft, to the squirrel-cage induction motor, and the rotational speeds of both shafts are the same. For this reason, it is necessary to replace the rotary blades with different shapes on both shafts, and it is troublesome and troublesome to replace the rotary blades.

  Therefore, by arbitrarily changing the rotation speed of one rotary blade driven by a squirrel-cage induction motor using an inverter, it is pulverized to an appropriate particle size according to the shape, size, hardness, type, etc. of the material to be crushed. In addition, since the number of rotating blades is not limited to one but only one, a driving control method for a pulverizer capable of omitting components has been proposed in recent years.

  That is, according to this drive control method, the rotation speed of the rotary blade of the squirrel-cage induction motor can be set finely and freely by the inverter, so that the rotation speed of the rotary blade can be changed according to the shape, size, hardness, type, etc. of the material to be crushed. By simply selecting the optimal number, the material to be crushed can be easily crushed to an appropriate particle size, and the number of components can be omitted because only one rotating shaft or rotating blade is required for the cage motor (for example, Patent Document 1).

  FIG. 6 is a longitudinal sectional view of a drive control device for a conventional crusher described in Patent Document 1. As shown in FIG.

  As shown in FIG. 6, in this example, the pulverizer includes a pulverizer body 7 in which a rotary blade 9 is provided in an internal pulverization chamber 8 in a horizontal direction, and a driving basket that rotates the rotary blade 9 via a rotary shaft 10. The shape induction motor 1, a crusher main body 7, and a squirrel-cage induction motor 1 are installed and a base 11 fixed by bolts, nuts, welding, or the like.

  The pulverizer body 7 is formed in a hopper shape. A supply port 12 for supplying a material to be crushed (not shown) to be pulverized and an upper portion of the hopper-like pulverization chamber 8 A rotary blade 9 is formed in the lower part, and a discharge port 13 is formed in the lowermost part of the grinding chamber 8.

  The rotating shaft 10 is inserted into the left and right flanges 14 and 15 of the crusher body 7, the left and right flanges 16 and 17 of the squirrel-cage induction motor 1, the left-side flange 18 of the squirrel-cage induction motor 1, and the hollow bearing 19. Thus, the rotating shaft 10 is rotated by the squirrel-cage induction motor 1 through a gear mechanism.

  The squirrel-cage induction motor 1 is fixed to the motor flanges 16 and 17. Reference numerals 20, 21, 22, and 23 in the figure denote bearings, and reference numerals 24, 25, and 26 in the figure denote seal flanges.

  Moreover, although not shown in figure, the well-known fixed blade is provided as what grind | pulverizes a to-be-ground material.

  Thereby, by driving the squirrel-cage induction motor 1, the rotary blade rotates and the material to be crushed can be pulverized.

  FIG. 7 is an electric circuit diagram of a conventional crusher drive control device described in Patent Document 1. In FIG.

  As shown in FIG. 7, in this example, the main power source 30, the breaker 31, the inverter controller 3 that changes the rotation speed by changing the frequency of the squirrel-cage induction motor 1, and the steady-state current due to load abnormality A thermal relay 32 that opens the circuit by detecting an increase and protects the cage induction motor 1, an anti-reverse relay 33 that detects a connection error of the power source and prevents reverse rotation of the cage induction motor 1, and reverse rotation prevention When the relay 33 detects it, it comprises a contact 34 that does not operate the inverter controller 3 and an operation stop switch 35.

  Thereby, the rotation speed of the rotary blade can be changed by changing the rotation speed of the squirrel-cage induction motor 1 by the inverter controller 3.

As described above, since the rotational speed of the rotary blade driven by the squirrel-cage induction motor 1 can be set finely and freely, the rotational speed of the rotary blade is selected as the optimum condition according to the shape, size, hardness, type, etc. of the material to be crushed. Thus, the material to be crushed can be easily pulverized to an appropriate particle size, and the components can be omitted because only one rotating shaft or rotating blade of the squirrel-cage induction motor 1 is required.
JP 2000-70749 A

  However, in the above-described conventional configuration, even if an increase in steady current due to abnormal load of the squirrel-cage induction motor 1 occurs only for a few seconds due to the shape, size, hardness, type, etc. of the material to be crushed, for example, the inverter controller 3 Can output current only up to 150% of the rated current of the inverter, so the overload protection function inside the inverter controller 3 operates and the output stops even for a few seconds, and the material to be crushed between the rotating blade and the fixed blade However, the squirrel-cage induction motor 1 is driven even when the material to be pulverized is not pulverized, and thus there is a problem that power consumption is wasted.

  The present invention solves the above-mentioned conventional problems, and can be operated without any problem if the steady current increase due to load abnormality is several seconds, and if the load current is smaller than the set current, the power consumption is reduced. An object of the present invention is to provide a drive control device and a drive control method for a pulverizer that reduce waste.

  In order to achieve the above-mentioned object, the present invention provides a control method for a pulverizer having a squirrel-cage induction motor for driving a rotary blade for pulverizing a material to be crushed supplied to a pulverization chamber of the pulverizer body. When the load current of the squirrel-cage induction motor is smaller than a set current when the induction motor is operated at a constant speed using a commercial power source, if the load current of the squirrel-cage induction motor becomes smaller than a set current, the rotation speed is lower than the predetermined speed after a predetermined time. When switching to variable speed operation and the cage induction motor is operating at variable speed at a speed lower than the predetermined speed, if the load current of the cage induction motor becomes larger than the set current, the commercial power supply is instantaneously The operation is switched to the constant speed operation at the predetermined rotational speed using the.

  As a result, when the load current becomes larger than the set current, operation is performed by a constant speed operation controller using a commercial power supply. You can drive. Further, when the load current is smaller than the set current, the variable speed operation is performed at a rotational speed lower than the predetermined rotational speed, so that waste of power consumption can be reduced.

  According to the drive control device and drive control method of the pulverizer of the injection molding machine of the present invention, when the material to be pulverized is pulverized, the load of the cage induction motor depends on the shape, size, hardness, type, etc. of the material to be pulverized Even if the steady-state current increases due to the abnormality, the system can be operated without any problem for a few seconds. Further, when the material to be crushed is not pulverized, waste of power consumption can be reduced.

  A pulverizer drive control device according to a first aspect of the present invention includes a squirrel-cage induction motor that drives a rotary blade for pulverizing a material to be crushed supplied to a pulverization chamber of a pulverizer body, and the squirrel-cage induction motor. A constant speed operation controller that operates at a constant speed using a commercial power source, an inverter controller that operates the cage induction motor at a variable speed at a speed lower than the predetermined speed, and a load of the cage induction motor A load current detector for detecting current; a current comparator for comparing a load current detected by the load current detector with a preset set current; and the squirrel-cage induction motor is controlled at a constant speed by the constant speed operation controller. If the load current becomes smaller than the set current during operation, the inverter controller is switched to operation after a predetermined time, and the inverter controller By when the squirrel-cage induction motors are variable speed operation, if greater than the load current is the set current, in which a switching controller for switching the operation by the constant-speed operation controller instantly.

  As a result, when the material to be crushed is being pulverized, the squirrel-cage induction motor operates at a constant speed using a commercial power source, and therefore the squirrel-cage induction motor depends on the shape, size, hardness, type, etc. of the material to be crushed. Even if the steady current increases due to an abnormality in the load, it can be operated at a constant speed without any problem within a few seconds. Further, when the material to be crushed is not pulverized, the squirrel-cage induction motor can reduce the waste of power consumption because the squirrel-cage induction motor is operating at a variable speed at a rotational speed lower than a predetermined rotational speed.

  According to a second aspect of the invention, there is provided a pulverizer drive control method according to a second aspect of the present invention. In the drive control method, when the squirrel-cage induction motor is operated at a constant speed using a commercial power source at a predetermined speed, if the load current of the squirrel-cage induction motor becomes smaller than a set current, the The load current of the squirrel-cage induction motor is changed to the set current when the squirrel-cage induction motor is switched to a variable speed operation at a speed lower than the predetermined speed and the squirrel-cage induction motor is operated at a variable speed at a speed lower than the predetermined speed. If it becomes larger, the operation is instantaneously switched to the constant speed operation at the predetermined rotational speed using a commercial power source.

  As a result, when the material to be crushed is being pulverized, the squirrel-cage induction motor operates at a constant speed using a commercial power source, and therefore the squirrel-cage induction motor depends on the shape, size, hardness, type, etc. of the material to be crushed. Even if the steady current increases due to an abnormality in the load, it can be operated at a constant speed without any problem within a few seconds. Further, when the material to be crushed is not pulverized, the squirrel-cage induction motor can reduce the waste of power consumption because the squirrel-cage induction motor is operating at a variable speed at a rotational speed lower than a predetermined rotational speed.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiment.

(Embodiment 1)
FIG. 1 is a system block diagram of a pulverizer drive control device in the present embodiment, FIG. 2 is a flowchart of a pulverizer drive control method of the same embodiment, and FIG. FIG. 4 is a characteristic diagram showing the relationship between time, load current, and operating state when the load current of the squirrel-cage induction motor is larger than the set current of the current comparator during variable speed operation. FIG. 5 is a characteristic diagram showing the relationship between time, load current, and operating state when the load current of the squirrel-cage induction motor is smaller than the set current of the current comparator when the induction motor is operated at a constant speed. It is the characteristic view which compared the power consumption of this drive control apparatus and the conventional drive control apparatus.

  In FIG. 1, a constant speed operation controller 2 uses a commercial power source and operates a squirrel-cage induction motor 1 at a predetermined speed at a constant speed. The inverter controller 3 operates at a variable speed at a rotation speed lower than a predetermined rotation speed. The load current detector 4 detects the load current of the squirrel-cage induction motor 1 every moment. The current comparator 5 compares the load current output from the load current detector 4 with a preset set current.

  The switching controller 6 instantaneously switches to the operation by the constant speed operation controller 2 if the load current becomes larger than the set current when the squirrel-cage induction motor 1 is operated at a variable speed by the inverter controller 3. When the squirrel-cage induction motor 1 is operated at a constant speed, if the load current becomes smaller than the set current, the operation is switched to the operation by the inverter controller 3 after a predetermined time.

  The squirrel-cage induction motor 1 and the constant-speed operation controller 2, the squirrel-cage induction motor 1 and the inverter controller 3, the constant-speed operation controller 2 through the load current detector 4 and the inverter controller 3 through the load current detector 4 The switching controller 6, the load current detector 4 and the current comparator 5, and the current comparator 5 and the switching controller 6 are electrically connected to each other.

  The drive control device for the pulverizer of the present embodiment further operates the squirrel-cage induction motor 1 at a constant speed at a predetermined rotational speed in addition to the configuration of the electric circuit diagram of the drive control device for the conventional pulverizer shown in FIG. The constant speed operation controller 2, the load current detector 4 that detects the load current of the squirrel-cage induction motor 1 momentarily, and the current that compares the load current output from the load current detector 4 with a preset set current When the squirrel-cage induction motor 1 is operated at a variable speed by the comparator 5 and the inverter controller 3, if the load current becomes larger than the set current, the operation is instantaneously switched to the operation by the constant speed operation controller 2, and the constant speed operation controller 2 When the squirrel-cage induction motor 1 is operated at a constant speed, the switching controller that switches to the operation by the inverter controller 3 after a predetermined time if the load current becomes smaller than the set current. It is that the La 6 is provided.

  The operation and action of the crusher drive control apparatus configured as described above will be described below with reference to FIGS. 2, 3, and 4. FIG.

  As STEP 50 in FIG. 2, the operation button of the squirrel-cage induction motor that rotates the rotary blade is pushed, the operation starts, and STEP 50 ends, and STEP 51 is entered.

  In STEP 51, the squirrel-cage induction motor is operated at a rotational speed lower than a predetermined rotational speed by the inverter controller from the switching controller, and STEP 51 ends, and STEP 52 is entered.

  In STEP52, if the load current of the squirrel-cage induction motor detected by the load current detector is larger than the set current set in the current comparator, STEP52 ends and the process goes to STEP53.

  In STEP 53, the squirrel-cage induction motor is switched to the constant speed operation by the constant speed operation controller from the switching controller, and STEP 53 ends, and the process proceeds to STEP 54.

  In STEP 54, counting of the constant speed operation time by the timer is started, and STEP 54 ends, and the process enters STEP 55.

  In STEP55, when the constant speed operation time counted by the timer becomes equal to or longer than the timer set time, STEP55 ends and the process enters STEP51. Further, if the constant speed operation time counted by the timer is smaller than the timer set time, STEP 55 ends and STEP 56 is entered.

  In STEP 56, if the load current of the squirrel-cage induction motor detected by the load current detector is smaller than the set current set in the current comparator, STEP 56 ends and the process goes to STEP 54. Further, if the load current of the squirrel-cage induction motor detected by the load current detector is larger than the set current set in the current comparator, STEP 56 is terminated and STEP 57 is entered.

  In STEP57, the constant speed operation time by the timer is cleared to zero, and STEP57 ends, and the process proceeds to STEP54.

  Next, the relationship between the time and load current and the operating state when the load current of the squirrel-cage induction motor is larger than the set current of the current comparator when the squirrel-cage induction motor is operating at a speed will be described.

  In FIG. 3, when the squirrel-cage induction motor is operated at a high speed, when the material to be crushed is supplied to the pulverization chamber of the pulverizer body, a load is applied to the rotating blade to be crushed, so that the squirrel-cage induction motor is driven. Since the load current of the squirrel is larger than the set current set in the current comparator, an example in which this is detected and the squirrel-cage induction motor is instantaneously switched to the constant speed operation by the constant speed operation controller is shown.

  Next, the relationship between the time and load current and the operating state when the load current of the squirrel-cage induction motor is smaller than the set current of the current comparator when the squirrel-cage induction motor is operated at a constant speed will be described.

  In FIG. 4, when the squirrel-cage induction motor is operating at a constant speed, if the material to be crushed is not supplied to the pulverization chamber of the pulverizer body, the load of the rotating blade to be crushed is small, so Since the load current is smaller than the set current set in the current comparator, if this is detected and the load current is smaller than the set current for the preset time set by the timer, the squirrel-cage induction motor is connected to the inverter controller from the switching controller. The example which switches to the variable speed driving | running | working below below the predetermined rotation speed by is shown.

  From the above, when the material to be pulverized is being pulverized, the squirrel-cage induction motor operates at a constant speed using a commercial power supply, so the squirrel-cage induction motor depends on the shape, size, hardness, type, etc. Even if the steady-state current increases due to an abnormality in the load, it can be operated without any problem within a few seconds. Further, when the material to be crushed is not pulverized, the squirrel-cage induction motor can reduce the waste of power consumption because the squirrel-cage induction motor is operating at a variable speed at a rotational speed lower than a predetermined rotational speed.

  FIG. 4 shows a comparison of the power consumption of the conventional pulverizer drive control device and the pulverizer drive control device of the present invention. As a result, a significant power saving can be achieved and the hatched area is saved. The power consumption of the drive control device of the present invention was 0.8 kWh compared to the power consumption of 1.4 kWh of the conventional drive control device, confirming that the power consumption was reduced by about 40.0% compared with the conventional drive control device. .

  As described above, the drive control device and the drive control method for a pulverizer according to the present invention detect a load current of a squirrel-cage induction motor, and when it is determined that the load is heavy, a predetermined rotational speed using a commercial power source is determined. When constant speed operation is performed and it is determined that the load is light, variable speed operation is performed at a lower speed than the predetermined speed using the inverter controller, reducing waste of power consumption. It can also be applied to applications.

The system block diagram of the drive control apparatus of the grinder in embodiment of this invention Flow chart of drive control method for crusher of the embodiment A characteristic showing the relationship between the time, load current, and operating state when the load current of the squirrel-cage induction motor changes more than the set current of the current comparator when the squirrel-cage induction motor of the same embodiment is operating at variable speed. Figure A characteristic showing the relationship between time, load current, and operating state when the load current of the squirrel-cage induction motor changes smaller than the set current of the current comparator when the squirrel-cage induction motor of the embodiment is operated at a constant speed. Figure A characteristic diagram comparing the power consumption of the drive control device of the same embodiment and the conventional drive control device Longitudinal sectional view of a conventional crusher drive control device Electric circuit diagram of conventional crusher drive control device

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cage type induction motor 2 Constant speed operation controller 3 Inverter controller 4 Load current detector 5 Current comparator 6 Switching controller

Claims (2)

A squirrel-cage induction motor that drives a rotary blade for crushing the material to be crushed supplied to the crushing chamber of the crusher body;
A constant speed operation controller for operating the cage induction motor at a constant speed using a commercial power source at a predetermined speed;
An inverter controller for variable speed operation of the squirrel-cage induction motor at a rotational speed lower than the predetermined rotational speed;
A load current detector for detecting a load current of the cage induction motor;
A current comparator that compares the load current detected by the load current detector with a preset current;
When the squirrel-cage induction motor is operated at a constant speed by the constant-speed operation controller, if the load current becomes smaller than the set current, the operation is switched to the operation by the inverter controller after a predetermined time, and the squirrel-cage operation is performed by the inverter controller. A pulverizer drive control device comprising: a switching controller that instantaneously switches to operation by the constant speed operation controller when the load current becomes larger than the set current during variable speed operation of the induction motor. A drive control method for a pulverizer having a squirrel-cage induction motor for driving a rotary blade for pulverizing a material to be crushed supplied to a pulverization chamber of a pulverizer body,
If the load current of the squirrel-cage induction motor is smaller than a set current when the squirrel-cage induction motor is operated at a constant speed using a commercial power source at a predetermined speed, the rotational speed is lower than the predetermined speed after a predetermined time. If the load current of the squirrel-cage induction motor becomes larger than the set current when the squirrel-cage induction motor is being operated at a variable speed at a speed lower than the predetermined speed, the instantaneous change will be instantaneous. A pulverizer drive control method for switching to constant speed operation at a predetermined rotational speed using a commercial power source.

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