AU2021371515B2 - Crushing load control circuitry of crusher and method of controlling crushing load of crusher - Google Patents

Abstract

This crusher crushing load control device comprises: a load response acquisition unit for acquiring, as an unprocessed load response, a load response obtained as a response for a given command value outputted with respect to a given control subject of a crusher; a pre-processing unit for pre-processing the unprocessed load response to obtain a load response; a feedback control unit for generating a new command value on the basis of the deviation between the load response and a prescribed target load value; and a control parameter adjustment unit for adjusting a control parameter of the feedback control unit on the basis of the load response. The pre-processing unit has a steady-state characteristic extraction filter for attenuating a crushing oscillation unique to the crusher that is included in the unprocessed load response.

Description

DESCRIPTION Title of Invention: CRUSHING LOAD CONTROL CIRCUITRY OF CRUSHER AND METHOD OF CONTROLLING CRUSHING LOAD OF CRUSHER Technical Field

[0001] The present disclosure relates to crushing load control circuitry of a crusher, such as a gyratory crusher or impact crusher utilized to crush rocks, ores, and the like or a uniaxial shearing crusher utilized to crush waste and the like, and a method of controlling a crushing load of the crusher.

Background Art

[0002] Conventionally known are gyratory crushers configured such that: a crushing chamber is formed between a conical tubular concave and a truncated conical mantle located inside the concave; and raw stones (objects to be crushed) supplied from a raw material hopper to the crushing chamber are sandwiched between the concave and the mantle and are crushed. The mantle is driven by an electric motor so as to perform eccentric gyratory motion. A gap between a crushing surface of the concave and a crushing surface of the mantle periodically changes. The particle size of a crushed object is determined by a dimension (closed set) of an outlet set (opening) at a position where the gap is the narrowest. The gyratory crushers are classified into hydraulic gyratory crushers and mechanical gyratory crushers according to a method of changing an outlet set amount. The hydraulic gyratory crusher includes a hydraulic cylinder that lifts or lowers the mantle relative to the concave that is positioned and fixed. The mechanical gyratory crusher includes an electric motor that lifts or lowers the concave relative to the mantle.

[0003] To stably and efficiently operate the above gyratory crusher, the gyratory crusher needs to be operated in a state where the crushing chamber is fully filled with the raw stones (i.e., a choke feed state). A time it takes for the raw stones to pass through the crushing chamber changes depending on the properties of the raw stones, such as the particle size of the raw stone and the moisture of the raw stone. Therefore, the choke feed state cannot be continued by the fixed amount supply of the raw stones. To solve this problem, for example, PTL 1 discloses that to maintain the choke feed state, the supply amount of raw stones is adjusted such that a level amount of the raw stones of a hopper which is detected by a level switch is maintained constant.

[0004] According to the gyratory crushers, even when the choke feed state is maintained, the load of the gyratory crusher may change depending on changes in the properties, moisture amount, and the like of the raw stones. Moreover, the gyratory crusher may be overloaded due to the clogging of foreign matters, a packing phenomenon of the raw stones, or the like. To solve this problem, for example, PTL 2 discloses that: the magnitude of the load is determined based on hydraulic pressure of the hydraulic cylinder and a current value of the electric motor; and the outlet set amount is adjusted based on the determination result. Herein, on-off control of repeating oil supply to (or oil discharge from) the hydraulic cylinder for a predetermined period of time is performed until a detected value of the outlet set amount reaches a target value.

Citation List Patent Literature

[0005] PTL 1: Japanese Laid-Open Patent Application Publication No. 10-272375 PTL 2: Japanese Laid-Open Patent Application Publication No. 55-5718

Summary of Invention

[0005a] It is an object of the present invention to overcome and/or alleviate one or more of the disadvantages of the prior art or provide the consumer with a useful or commercial choice.

[0005b] In one aspect, the invention provides crushing load control circuitry of a crusher, the crushing load control circuitry including: a load response acquirer that acquires, as an unprocessed load response, a crushing load obtained as a response of a command value that is output with respect to a control target of the crusher; a preprocessor that preprocesses the unprocessed load response to obtain a load response; feedback controlling circuitry that generates a new command value based on a deviation between the load response and a predetermined load target value; and a control parameter adjuster that adjusts a control parameter of the feedback controlling circuitry based on the load response, wherein the preprocessor includes a steady characteristic extraction filter that attenuates crush vibration which is included in the unprocessed load response and is specific to the crusher.

[0005c] In one aspect, the invention provides a method of controlling a crushing load of a crusher, the method including: acquiring, as an unprocessed load response, a crushing load obtained as a response of a command value that is output with respect to a control target of the crusher; preprocessing the unprocessed load response; generating a new command value by using a feedback controller based on a deviation between a load response obtained by preprocessing the unprocessed load response and a predetermined load target value; and adjusting a control parameter of the feedback controller based on the load response, wherein the preprocessing step includes attenuating crush vibration which is included in the unprocessed load response and is specific to the crusher, and extracting a steady characteristic from the unprocessed load response.

[0006] To realize automatic operation of the gyratory crusher, the inventors of the present application are considering controlling at least one of the outlet set amount of the gyratory crusher and the supply amount of raw stones by using feedback control instead of the on-off control. More specifically, the current value of the electric motor or the hydraulic pressure value of the hydraulic cylinder is used as a load index, and from a deviation between a measured value of the load index which is obtained as a response to a certain operation amount and a target value of the load index, a new operation amount is calculated by utilizing control algorithm. Thus, the load index is controlled so as to fall within a predetermined steady range.

[0007] However, since the properties (hardness, moisture content, etc.) of the raw stones to be fed vary, the response sensitivity of the gyratory crusher increases or decreases about ten times at most, and an appropriate value of a control parameter in the feedback control changes. Therefore, if the feedback control is performed in a state where the control parameter is fixed for a control target of the gyratory crusher, problems occur, for example, an unstable phenomenon such as hunting occurs, or reaching the target value requires time.

[0008] The present disclosure was made under these circumstances, and an object of some embodiments of the present disclosure is to propose crushing load control circuitry of a crusher and a method of controlling a crushing load of a crusher, each of which reduces a work time and manpower required to adjust a control parameter in order to realize continuation of a stable

operation of the crusher.

[0009] Crushing load control circuitry of a crusher according to one aspect of the present disclosure includes: a load response acquirer that acquires, as an unprocessed load response, a crushing load obtained as a response of a command value that is output with respect to a control target of the crusher; a preprocessor that preprocesses the unprocessed load response to obtain a load response; feedback controlling circuitry that generates a new command value based on a deviation between the load response and a predetermined load target value; and a control parameter adjuster that adjusts a control parameter of the feedback controlling circuitry based on the load response. The preprocessor includes a steady characteristic extraction filter that attenuates crush vibration which is included in the unprocessed load response and is specific to the crusher.

[0010] According to the crushing load control circuitry of the crusher configured as above, the load response input to the feedback controlling circuitry and the control parameter adjuster is dominated by the processing performed by the preprocessor. To be specific, the load response from which influence of the crush vibration has been eliminated by the preprocessing can be regarded as the load response characteristic of the crusher. Since the filter characteristic of the preprocessor can be designed arbitrarily, the control parameter adjuster can be designed in accordance with the filter characteristic. With this, the automatic adjustment of the control parameter of the feedback controlling circuitry can be theoretically performed by using the control parameter adjuster. Therefore, the work time and manpower required to adjust the control parameter can be reduced. Moreover, the accuracy of the determination regarding whether or not the adjustment of the control parameter is required can be improved. This can contribute to the continuation of the stable operation of the crusher.

[0011] Moreover, a method of controlling a crushing load of a crusher according to one aspect of the present disclosure includes: acquiring, as an unprocessed load response, a crushing load obtained as a response of a command value that is output with respect to a control target of a crusher; preprocessing the unprocessed load response; generating a new command value by using a feedback controller based on a deviation between a load response obtained by preprocessing the unprocessed load response and a predetermined load target value; and adjusting a control parameter of the feedback controller based on the load response. The preprocessing step includes: attenuating crush vibration which is included in the unprocessed load response and is specific to the crusher; and extracting a steady characteristic from the unprocessed load response.

[0012] According to the method of controlling the crushing load of the crusher, the load response utilized in the step of generating the new command value and the step of adjusting the control parameter is dominated by the preprocessing. To be specific, the load response from which influence of the crush vibration has been eliminated by the preprocessing can be regarded as the load response characteristic of the crusher. Since the details of the processing of extracting the steady characteristic from the unprocessed load response in the preprocessing can be designed arbitrarily, the processing of adjusting the control parameter can be designed in accordance with the preprocessing. With this, the automatic adjustment of the control parameter of the feedback controller can be theoretically performed. Therefore, the work time and manpower required to adjust the control parameter can be reduced. Moreover, the accuracy of the determination regarding whether or not the adjustment of the control parameter is required can be improved. This can contribute to the continuation of the stable operation of the crusher.

4a

[0013] The present disclosure can in some embodiments propose crushing load control circuitry of a crusher and a method of controlling a crushing load of a crusher, each of which reduces a work time and manpower required to adjust a control parameter.

Brief Description of Drawings

[0014] FIG. 1 is a diagram showing a schematic configuration of a gyratory crusher according to one embodiment of the present disclosure. FIG. 2 is a diagram showing the configuration of a control system of the gyratory crusher shown in FIG. 1. FIG. 3 is a diagram showing the configuration of crushing load control according to First Example. FIG. 4 is a flowchart showing processing of the crushing load control according to First Example. FIG. 5 is a diagram for explaining characteristics of an amplitude and frequency of an unprocessed load response. FIG. 6 is a table showing a relation between a load response and an FFT analysis result of the load response. FIG. 7 shows graphs of simulation results of the crushing load control. FIG. 8 is a diagram showing the configuration of the crushing load control according to Second Example.

FIG. 9 is a flowchart showing initial control parameter adjustment processing in the crushing load control according to Second Example. FIG. 10A is a diagram for explaining the initial control parameter adjustment processing. FIG. 1OB is a diagram for explaining the initial control parameter adjustment processing. FIG. 1OC is a diagram for explaining the initial control parameter adjustment processing.

Description of Embodiments

[0015] Next, an embodiment in which the present disclosure is applied to a gyratory crusher will be described with reference to the drawings. FIG. 1 is a diagram showing a schematic configuration a crusher 1 according to one embodiment of the present disclosure.

[0016] Schematic Configuration of Crusher 1 As shown in FIG. 1, the crusher 1 includes: a hopper 2 that stores raw stones (objects to be crushed); a supplier 4 that supplies the raw stones to the hopper 2; a mantle 13 and a concave 14 which sandwich and crush the raw stones falling from the hopper 2; an electric motor 8 that is a gyratory driver for the mantle 13; a power transmission 80 that transmits rotational power from the electric motor 8 to the mantle 13; an outlet set adjuster 10 that lifts or lowers the mantle 13 relative to the concave 14; and control circuitry 9 that controls the operation of the crusher 1.

[0017] The crusher 1 further includes a frame 3, and the frame 3 includes a top frame 31 and a bottom frame 32. The conical tubular concave 14 is located at an inner periphery of the top frame 31. The truncated conical mantle 13 is located inside the concave 14. A crushing chamber 16 having a wedge-shaped vertical cross section is located between a crushing surface of the concave 14 and a crushing surface of the mantle 13 which face each other with a gap.

[0018] The hopper 2 is located at an upper portion of the top frame 31. For example, the supplier 4 includes a conveyor (not shown) and can adjust the supply amount of raw stones supplied to the hopper 2. An electric motor 41 that is a driver for the supplier 4 is a variable speed motor and is driven and controlled by a motor driver 43.

[0019] The mantle 13 is attached to a mantle core 12 fixed to an upper portion of a main shaft 5. The main shaft 5 is located in the frame 3 such that a center axis of the main shaft 5 is inclined relative to a vertical direction. An upper end of the main shaft 5 is rotatably supported by an upper bearing 34 located at an upper end portion of the top frame 31. A lower portion of the main shaft 5 is fittingly inserted into an inner bushing 51. The inner bushing 51 is fixed to an eccentric sleeve 52. The eccentric sleeve 52 is fittingly inserted into an outer bushing 53 located at the bottom frame 32. A lower portion of the eccentric sleeve 52 is supported by a sliding bearing 66 located at a cylinder tube 63 of a hydraulic cylinder 6. A lower end of the main shaft 5 is supported by a sliding bearing 62 located at a ram 61 of the hydraulic cylinder 6.

[0020] The electric motor 8 is located outside the frame 3. A rotational frequency sensor 25 and a torque sensor 26 are located at the electric motor 8. The rotational frequency sensor 25 detects a rotational frequency of the electric motor 8, and the torque sensor 26 detects output torque of the electric motor 8. The electric motor 8 is driven and controlled by a motor driver 88.

[0021] The power transmission 80 transmits power from the electric motor 8 to the main shaft 5 to which the mantle 13 is fixed. The power transmission 80 includes: a horizontal shaft 83; a belt (or chain) transmission 82 that transmits rotational power from an output shaft 81 of the electric motor 8 to the horizontal shaft 83; the eccentric sleeve 52; and a bevel gear transmission 84 that transmits rotational power from the horizontal shaft 83 to the eccentric sleeve 52. When the eccentric sleeve 52 is rotated by the output of the electric motor 8, the main shaft 5 inserted in the eccentric sleeve 52 eccentrically turns. With this, the mantle 13 performs eccentric gyratory motion, i.e., so-called precession, with respect to the concave 14 that is positioned and fixed. By the eccentric gyratory motion of the mantle 13, an outlet set amount (opening) between the crushing surface of the mantle 13 and the crushing surface of the concave 14 changes depending on a turning position of the main shaft 5.

[0022] The crusher 1 according to the present embodiment includes the hydraulic cylinder 6 as the outlet set adjuster 10. The mantle 13 moves up and down relative to the concave 14 by the operation of the hydraulic cylinder 6 to change the outlet set amount (closed set) at a position where the gap between the crushing surface of the concave 14 and the crushing surface of the mantle 13 is the narrowest. The hydraulic cylinder 6 also functions as a pressure receiver that receives crushing pressure applied to the mantle 13.

[0023] The hydraulic cylinder 6 includes: the cylinder tube 63; the ram 61 that slides in the cylinder tube 63; an outlet set sensor 23; an oil tank 67; and a hydraulic circuit 7. For example, the outlet set sensor 23 is a contact or noncontact position sensor that detects the position (displacement) of the ram 61. The position of the mantle 13 relative to the concave 14 in a height direction is calculated from the position of the ram 61 which is detected by the outlet set sensor 23, and the outlet set amount is calculated from a relative positional relation between the concave 14 and the mantle 13.

[0024] A hydraulic chamber 65 whose volume changes by the displacement of the ram 61 is located in the cylinder tube 63. The hydraulic circuit 7 is in connection with the hydraulic chamber 65. The ram 61 moves upward by the supply of the operating oil from the oil tank 67 through the hydraulic circuit 7 to the hydraulic chamber 65. Moreover, the ram 61 moves downward by the discharge of the operating oil from the hydraulic chamber 65 through the hydraulic circuit 7 to the oil tank 67.

[0025] The hydraulic circuit 7 includes: a communication pipe 71 that communicates with a lower portion of the hydraulic chamber 65; an accumulator 72 (or a balance cylinder) located at the communication pipe 71; an oil supply pipe 73 connected to the communication pipe 71; and an oil discharge pipe 74 connected to the oil supply pipe 73. However, the configuration of the hydraulic circuit 7 is not limited to the present embodiment. A strainer 75, a gear pump 76, a check valve 77, and a normally closed shut-off valve 78 are located at the oil supply pipe 73 in this order from an upstream side along the flow of the operating oil from the oil tank 67 to the hydraulic chamber 65. The gear pump 76 is driven by a pump motor 68. The pump motor 68 is an electric motor and is driven and controlled by a motor driver 69. A pressure sensor 24 that detects the pressure of the operating oil of the hydraulic chamber 65 is further located at the hydraulic chamber 65, the communication pipe 71, or the oil supply pipe 73. Theoildischarge pipe 74 is connected to a portion of the oil supply pipe 73 which is located between the check valve 77 and the shut-off valve 78. A normally closed shut-off valve 79 is located at the oil discharge pipe 74.

[0026] Configuration of Control System of Crusher 1 FIG. 2 is a diagram showing the configuration of a control system of the crusher 1. As shown in FIG. 2, various types of equipment, such as the outlet set sensor 23, the pressure sensor 24, the rotational frequency sensor 25, and the torque sensor 26, are in connection with the control circuitry 9 through wired communication or wireless communication so as to be able to transmit and receive signals (or transmit signals). An alarm outputter 99 and a display outputter 98 are in connection with the control circuitry 9. The alarm outputter 99 outputs an alarm to an operator, and the display outputter 98 presents details and results of processing to the operator. Moreover, various types of equipment, such as the motor driver 43 of the electric motor 41 of the supplier 4, the motor driver 88 of the electric motor 8, the motor driver 69 of the pump motor 68, the shut-off valve 78, and the shut-off valve 79, are in connection with the control circuitry 9 through wired communication or wireless communication so as to be able to transmit and receive signals.

[0027] The control circuitry 9 is a so-called computer and includes a calculation processing portion such as a CPU, and a storage portion such as a ROM and a RAM (these are not shown). The storage portion includes a program executed by the calculation processing portion, various fixed data, and the like. The calculation processing portion transmits and receives data to and from external devices. Moreover, the calculation processing portion receives detection signals from various sensors and outputs control signals to components of the crusher 1.

[0028] The control circuitry 9 includes operation control circuitry 90 and crushing load control circuitry 91. The operation control circuitry 90 controls the operations of the components of the crusher 1. The crushing load control circuitry 91 controls a crushing load of the crusher 1. The operation control circuitry 90 includes functional components that are: controlling circuitry that controls the operation of the supplier 4; controlling circuitry that controls the operation of the outlet set adjuster 10 (hydraulic cylinder 6); and controlling circuitry that controls the operation of the electric motor 8. The crushing load control circuitry 91 includes functional components that are: feedback controlling circuitry 92 (feedback controller); a load response acquirer 94; a control parameter adjuster 95; a preprocessor 97; and display controlling circuitry 93. The control circuitry 9 performs processing as the above functional components in such a manner that the calculation processing portion reads and executes software such as the program stored in the storage portion. The control circuitry 9 may execute processing by centralized control performed by a single computer or may execute processing by distributed control performed by a plurality of computers in cooperation. Moreover, the control circuitry 9 may include a microcontroller, a programmable logic controller (PLC), or the like. The operation control circuitry 90 and the crushing load control circuitry 91 may be configured integrally or may be configured independently but communicable with each other.

[0029] Method of Operating Crusher 1 Herein, a method of operating the crusher 1 configured as above will be described. When starting the operation of the crusher 1, the control circuitry 9 operates the outlet set adjuster 10 such that the outlet set amount is set to a default value. The default value of the outlet set amount is preset in accordance with particle diameters of raw stones and crushed objects and the like. The control circuitry 9 operates the outlet set adjuster 10 based on the detected value of the outlet set sensor 23 such that the outlet set amount is set to the default value. When the outlet set amount is larger than the default value, the control circuitry 9 opens the shut-off valve 78 and operates the pump motor 68 to supply the oil to the hydraulic chamber 65. Moreover, when the outlet set amount is smaller than the default value, the control circuitry 9 opens the shut-off valve 78 and the shut-off valve 79 to discharge the oil from the hydraulic chamber 65.

[0030] Next, the control circuitry 9 starts the electric motor 8 and the supplier 4. By the operation of the supplier 4, the raw stones pass through the hopper 2 to be fed to the crushing chamber 16. The raw stones are crushed between the concave 14 and the mantle 13 that performs the eccentric gyratory motion, and are collected as a crushed product from a lower side of the bottom frame 32.

[0031] During the operation of the crusher 1 as above, the crushing load changes due to disturbances, such as the properties of the raw stones and a change in level of the raw stones in the hopper 2. Herein, the "crushing load" denotes a load applied to the output shaft 81 of the electric motor 8 when crushing the raw stones. When an excessive load that is a predetermined load or more is applied to the output shaft 81 of the electric motor 8, the rotation of the output shaft 81 is locked, and the electric motor 8 performs emergency stop by the operation of an excessive load protection circuit. Therefore, the crusher 1 includes a load measurer that measures a load index I that directly or indirectly indicates the crushing load, and the control circuitry 9 monitors the load index I measured during the crushing operation. Then, the control circuitry 9 performs crushing load control of adjusting at least one of the supply amount of raw stones supplied by the supplier 4 and the outlet set amount changed by the outlet set adjuster 10 such that the load index I is maintained within a predetermined steady range.

[0032] The crushing load is represented by a product of the rotational frequency of the output shaft 81 and the output torque of the output shaft 81. Therefore, the crushing load can be measured as the product of the rotational frequency detected by the rotational frequency sensor 25 and the output torque detected by the torque sensor 26. The rotational frequency of the output shaft 81 corresponds to the rotational frequency of the horizontal shaft 83 and the rotational frequency of the eccentric sleeve 52. Therefore, instead of the rotational frequency detected by the rotational frequency sensor 25, the rotational frequency detected by a rotational frequency sensor (not shown) located at the horizontal shaft 83 or the eccentric sleeve 52 may be used.

[0033] The crushing load correlates to a driving current of the electric motor 8. Therefore, a change in crushing load can be estimated based on a change in driving current of the electric motor 8. The driving current of the electric motor 8 can be measured as a detected value of a current sensor 88a included in the motor driver 88.

[0034] Moreover, the crushing load correlates to power consumption of the electric motor 8. Therefore, the change in crushing load can be estimated based on a change in power consumption of the electric motor 8. The power consumption of the electric motor 8 can be measured based on a product of the detected value of the current sensor 88a included in the motor driver 88 and a detected value of a voltage sensor 88b included in the motor driver 88.

[0035] Moreover, the crushing load correlates to crushing pressure. Therefore, the change in crushing load can be estimated based on a change in crushing pressure. The crushing pressure can be measured as the pressure of the hydraulic chamber 65 which is detected by the pressure sensor 24.

[0036] As above, as the load index I, at least one of the value of the product of the rotational frequency and the output torque, the value of the driving current of the electric motor 8, the value of the power consumption of the electric motor 8, and the value of the crushing pressure can be adopted. Then, in accordance with the adopted load index I, equipment that measures or detects the load index I is selected as the load measurer.

[0037] Crushing Load Control Performed by Crushing Load Control Circuitry 91 In the crushing load control circuitry 91, the load index I and a control target are preset, and various numerical values, such as a load target value and an initial control parameter of control algorithm, utilized for control are preset. As described above, the load index I is the measured value that directly or indirectly indicates the crushing load, and may be any one of the value of the product of the rotational frequency and the output torque, the value of the driving current of the electric motor 8, the value of the power consumption of the electric motor 8, and the value of the crushing pressure. Moreover, the control target is at least one of the supply amount of raw stones supplied by the supplier 4 and the outlet set amount changed by the outlet setadjuster10. When the amount of production is regarded as important, the crushing load control is performed such that the supply amount of raw stones is set to be constant, and the outlet set amount is variable. Moreover, when the particle size of the product is regarded as important, the crushing load control is performed such that the outlet set amount is set to be constant, and the supply amount of raw stones is variable. Hereinafter, First and Second Examples of the crushing load control performed by the crushing load control circuitry 91 will be described.

[0038] First Example of Crushing Load Control First, First Example of the crushing load control will be described. In First Example of the crushing load control performed by the crushing load control circuitry 91, after the crusher 1 is started, and the driving current value and the crushing pressure become respective predetermined steady operation values and are stabilized, i.e., the driving current value and the crushing pressure become a steady state, the crushing load control is started. FIG. 3 is a diagram showing the configuration of the crushing load control according to First

Example. FIG. 4 is a flowchart showing processing of the crushing load control according to First Example.

[0039] As shown in FIG. 3, the crushing load control circuitry 91 includes the load response acquirer 94, the preprocessor 97, the feedback controlling circuitry 92, the display controlling circuitry 93, and the control parameter adjuster 95. Hereinafter, the configuration related to the crushing load control will be described in accordance with the flow of the processing of the crushing load control with reference to FIGS. 3 and 4.

[0040] The operation control circuitry 90 operates a component that adjusts the control target, in accordance with a certain command value MVn-i (n is a natural number). The load response acquirer 94 of the crushing load control circuitry 91 acquires an unprocessed load response (i.e., a response waveform of a load index In-i corresponding to the command value

MV-i) from the load measurer that measures or detects the load index In i(Step S1). For example, when the driving current of the electric motor 8 is the load index I, the detected values which are detected by the current sensor 88a that detects the driving current of the electric motor 8 and are arranged in time series are generated as the unprocessed load response.

[0041] The preprocessor 97 performs preprocessing with respect to the unprocessed load response (Step S2). The preprocessor 97 includes two types of filters that are a noise elimination filter 97a and a steady characteristic extraction filter 97b.

[0042] The noise elimination filter 97a attenuates and eliminates high frequency noise of the unprocessed load response. The noise elimination filter 97a is, for example, a simple moving average filter that outputs a simple average of input signal values of past m time points (m is a natural number) while moving a present time point. However, as the noise elimination filter 97a, a known moving average filter other than the simple moving average filter may be adopted, or a first-order lag filter may be adopted.

[0043] The steady characteristic extraction filter 97b is a low-pass filter that attenuates a frequency component whose frequency is higher than a predetermined cutoff frequency. The steady characteristic extraction filter 97b extracts a steady characteristic from the unprocessed load response. FIG. 5 is a diagram for explaining the characteristics of the amplitude and frequency of the unprocessed load response. As shown in FIG. 5, the unprocessed load response includes: hunting caused by a change in response sensitivity to be extracted; and crush vibration, noise, and the like specific to the crusher 1. The steady characteristic extraction filter 97b is configured such that: the amplitude in a frequency domain representing the steady characteristic is maintained; and the amplitude of the frequency (hereinafter referred to as a

"natural vibration frequency") of the crush vibration specific to the crusher 1 is attenuated. More specifically, the steady characteristic extraction filter 97b is configured such that: the amplitude is maintained at the cutoff frequency or less (passband); and the amplitude is attenuated at more than the cutoff frequency (stopband). Such cutoff frequency is, for example, a minimum value of the natural vibration frequency. The natural vibration frequency can be analytically obtained in advance. When the unprocessed load response is processed by the steady characteristic extraction filter 97b, the amplitude in a frequency band including a frequency (hereinafter referred to as a "hunting frequency") at which the hunting occurs is extracted. The hunting frequency depends on the frequency characteristic of the steady characteristic extraction filter 97b. More specifically, a phase crossover frequency (i.e., a frequency at which the phase delay becomes 180) is defined by a phase delay characteristic of the steady characteristic extraction filter 97b. The control system becomes unstable in the frequency band of the phase crossover frequency, and this causes the hunting. Therefore, the frequency band of the phase crossover frequency is a hunting frequency band.

[0044] As above, the unprocessed load response from which the noise and the crush vibration are eliminated by the preprocessing performed by the preprocessor 97 is referred to as a "load response". The load response is utilized by the feedback controlling circuitry 92 for the generation of a next command value MV.

[0045] The feedback controlling circuitry 92 generates the command value MV. with respect to the control target such that the load index I falls within a predetermined steady range. In this example, the feedback controlling circuitry 92 adopts proportional integral derivative (PID) control algorithm as the control algorithm and generates the command value MV. from a deviation between a given load target value and the load response. However, the control algorithm of the feedback controlling circuitry 92 is not limited to this example and may be one selected from the group consisting of: proportional (P) control algorithm; proportional integrating (PI) control algorithm; proportional integral derivative control algorithm; and proportional derivative feedback (PDF) control algorithm.

[0046] The control parameter adjuster 95 appropriately tunes the control parameter of the feedback controlling circuitry 92 with respect to the response sensitivity that changes. Herein, the control parameter to be tuned is a control gain (proportional gain Kp) of the feedback controlling circuitry 92. In addition to the proportional gain Kp of the feedback controlling circuitry 92, the control parameter to be tuned may include at least one of a derivative gain Kd and an integral gain Ki.

[0047] The control parameter adjuster 95 performs frequency analysis of the load response by using FFT (fast Fourier transform) algorithm (Step S3). The control parameter adjuster 95 detects an increase (or an increase and decrease) in the response sensitivity based on a FFT analysis result (frequency analysis result) of the load response.

[0048] FIG. 6 is a table showing a relation between the load response and the FFT analysis result of the load response. FIG. 6 shows: the load response and the FFT analysis result of the load response in a case (a) where the response sensitivity has increased, and the control parameter has become relatively and excessively large; the load response and the FFT analysis result of the load response in a case (b) where a change in response sensitivity is adequately small, and the control parameter is appropriate; and the load response and the FFT analysis result of the load response in a case (c) where the response sensitivity has decreased, and the control parameter has become relatively and excessively small.

[0049] In the case (a), the load response largely fluctuates around the load target value, i.e., the hunting occurs, and a peak of the hunting frequency appears in the FFT analysis result. According to this, when the peak of the hunting frequency appears in the FFT analysis result of the load response, it is estimated that the response sensitivity has increased, and the control parameter has become relatively and excessively large.

[0050] In the case (c), the load response is smaller than the load target value, and the deviation of the load response from the load target value is continuously large. Moreover, in the FFT analysis result, the peak appears at a frequency (frequency lower than the hunting frequency) different from the hunting frequency. According to this, when the peak appears at the frequency lower than the hunting frequency in the FFT analysis result of the load response, it is estimated that the response sensitivity has decreased, and the control parameter has become relatively and excessively small.

[0051] In the case (b), the load response is substantially maintained at the load target value, and there is no peak in the FFT analysis result. According to this, when there is no peak in the FFT analysis result of the load response, it is estimated that the change in response sensitivity is adequately small, and the control parameter is appropriate.

[0052] As above, the increase or decrease in the response sensitivity of the crusher 1 can be detected based on the FFT analysis result of the load response.

[0053] When the control parameter adjuster 95 has detected the increase in the response sensitivity (Yes in Step S4), the control parameter adjuster 95 obtains the amplitude of the hunting and compares the amplitude of the hunting with a predetermined threshold (Step S5). The amplitude of the hunting may be a maximum amplitude or an average amplitude. When the amplitude of the hunting is the threshold or more (Yes in Step S5), the control parameter adjuster 95 adjusts the control parameter such that the control gain decreases (Step S6). Specifically, the control parameter adjuster 95 generates a new proportional gain Kpn by reducing the proportional gain Kp by a predetermined first proportional gain adjustment amount, and updates the proportional gain Kp by the new proportional gain Kp.

[0054] When the control parameter adjuster 95 does not detect the increase in the response sensitivity (No in Step S4) but detects the decrease in the response sensitivity (Yes in Step S7), the control parameter adjuster 95 obtains a deviation area of an arbitrary section. The deviation area is an accumulated value of the deviation between the load target value and the load response in the arbitrary section and is an area of a region surrounded by the load target value and the load response (see FIG. 6). When the obtained deviation area is a predetermined threshold or more (Yes in Step S8), the control parameter adjuster 95 adjusts the control parameter such that the control gain increases (Step S6). Specifically, the control parameter adjuster 95 generates the new proportional gain Kpn by increasing the proportional gain Kp by a predetermined second proportional gain adjustment amount, and updates the proportional gain Kp by the new proportional gain Kp.

[0055] When the response sensitivity of the crusher 1 decreases, and the deviation between the load target value and the load response increases due to disturbances or the like, it takes time to return the load response to the load target value. Therefore, when the response sensitivity has decreased as described above, it is desirable to adjust the control parameter. However, to suppress the hunting, the adjustment of the control parameter when the response sensitivity has decreased may be omitted.

[0056] The control parameter adjuster 95 does not adjust the control parameter when the change in response sensitivity is adequately small, when the response sensitivity has increased, but the amplitude of the hunting is less than the threshold, and when the response sensitivity has decreased, but the deviation area is less than the threshold.

[0057] As above, the control parameter is adjusted by the control parameter adjuster 95 so as to become a value corresponding to the present response sensitivity. The feedback controlling circuitry 92 in which the control parameter has been adjusted generates the new command value MV. from the deviation between the load target value and the load response based on speed PID control algorithm (Step S9).

[0058] The feedback controlling circuitry 92 outputs the generated new command value MVn to the operation control circuitry 90. The operation control circuitry 90 operates a component that adjusts the control target, in accordance with the new command value MVn. When the control target is the supply amount of raw stones supplied by the supplier 4, the supplier 4 operates in accordance with the new command value MV., and the supply amount of raw stones supplied to the hopper 2 changes. Moreover, when the control target is the outlet set amount changed by the outlet set adjuster 10, the hydraulic cylinder 6 operates in accordance with the new command value MV., and the outlet set amount changes.

[0059] When the control target changes in accordance with the new command value MV. as above, a response of the new command value MV. appears in the load index I. The crushing load control circuitry 91 returns to Step S Iand performs the crushing load control based on the unprocessed load response of the new command value MV. which is acquired by the load response acquirer 94. Even when the control parameter is adjusted as above, the change in response sensitivity may not be improved, and such case requires maintenance. Therefore, when the change in response sensitivity is continuously estimated even after a predetermined observation period (for example, several hours) has elapsed since the adjustment of the control parameter, the control parameter adjuster 95 may output an alarm to the alarm outputter 99 to inform the operator of the abnormality.

[0060] FIG. 7 shows graphs of the simulation results of the crushing load control. In FIG. 7, a graph (a) shows the outlet set amount, a graph (b) shows the supply amount of raw stones, a graph (c) shows the load response, a graph (d) shows a control gain adjustment value, and time axes (horizontal axes) of the graphs (a) to (d) correspond to each other. Herein, the crushing pressure (i.e., the pressure of the hydraulic chamber 65) is adopted as the load index I, and data obtained by subjecting raw data of the crushing pressure to preprocessing is shown as the load response. Moreover, the control gain is adopted as the control parameter to be adjusted, and the control gain adjustment value is shown by a ratio when an initial gain is one.

[0061] As shown in FIG. 7, after about 50 seconds from the start, the hunting appeared in the load response in accordance with the vibration of the outlet set amount. This was regarded as the increase in the response sensitivity, and after about 250 seconds, the control gain was adjusted to be reduced. As a result, after about 300 seconds, the response sensitivity was appropriately recovered, and the hunting was eliminated. In a state where the control gain was reduced, the characteristics of the raw stones were changed after about 600 seconds, and the load response fell below the load target value. This was regarded as the decrease in the response sensitivity, and after about 700 seconds, the control gain was adjusted to be increased. As a result, the low followability of the load response to the target value was improved, and the load response steeply increased. After about 800 seconds from the start, the response sensitivity was appropriately recovered, and the load response became substantially the load target value. After about 1,100 seconds from the start, the characteristics of the raw stones were changed.

The vibration of the outlet set amount was generated, and the hunting appeared in the load response. As with the above, the control gain was adjusted.

[0062] It is clear from the simulation results that even when the load response fluctuates in the middle of the operation, the load response returns to the load target value by the adjustment of the control gain, and therefore, stable crushing can be continued. Moreover, as is clear from the simulation results, when the system changes in the crusher 1, its response steeply appears in the load index I. However, the necessity of sensitively responding to this is low. Sensitively responding to this is not preferable from the viewpoint of the protection of the actuator. Due to such characteristics of the crusher 1, it is preferable to perform, as the preprocessing of the unprocessed load response, the noise elimination by the moving average and the extraction of the hunting by the low-pass filter.

[0063] Second Example of Crushing Load Control Next, Second Example of the crushing load control will be described. FIG. 8 is a diagram showing the configuration of the crushing load control according to Second Example. As shown in FIG. 8, the crushing load control circuitry 91 includes feedback controlling circuitry 920, the load response acquirer 94, a control parameter adjuster 950, and the preprocessor 97. Second Example is different from First Example regarding only the configurations of the feedback controlling circuitry 920 and the control parameter adjuster 950. Therefore, hereinafter, the configurations of the feedback controlling circuitry 920 and the control parameter adjuster 950 will be described in detail, and regarding the other configurations, the explanations in First Example are available, and the repetition of the same explanations are avoided.

[0064] The feedback controlling circuitry 920 is a PID controller that performs feedback control of the load response by using the proportional integral derivative (PID) control algorithm. The control parameter adjuster 950 performs data-driven controller tuning (fictitious reference iterative tuning; FRIT) for the control parameter of the feedback controlling circuitry 920 that is the PID controller. The control parameter adjuster 950 obtains an ideal control parameter of the feedback controlling circuitry 920 by using a pair of input and output data measured in a closed loop without performing system identification using periodic signals. Hereinafter, the flow of the setting of the initial control parameter which is performed by the crushing load control circuitry 91 will be described with reference to FIGS. 9 and 10A-10C. FIG. 9 is a flowchart showing processing of the crushing load control according to Second Example.

[0065] First, the control parameter adjuster 950 acquires the load response as a closed loop response characteristic (Step S11). Herein, as shown in FIG. 1OA, the control parameter adjuster 950 gives an excitation signal to the load target value. The feedback controlling circuitry 920 generates a command value based on the excitation signal and outputs the command value to the operation control circuitry 90. The load response acquirer 94 acquires the unprocessed load response as a closed loop response. The preprocessor 97 preprocesses the acquired unprocessed load response to obtain the load response. The configuration and processing details of the preprocessor 97 are the same as those in First Example. The control parameter adjuster 950 acquires this load response as the closed loop response characteristic.

[0066] To avoid destabilization and hunting, the control parameter (default control gain) of the feedback controlling circuitry 920 when first acquiring the closed loop response characteristic is set to a low value corresponding to the high response sensitivity.

[0067] To shorten a time it takes to adjust the initial control parameter, it is desirable to use not step input but impulse input (or the impulse input and the step input) for the excitation signal. Herein, when using the step input for the excitation signal, it is necessary to wait until the load adequately rises, in order to prevent the load response from being buried in noise. In contrast, when using the impulse input for the excitation signal, it is unnecessary to wait until the load adequately rises. Thus, the closed loop response characteristic can be acquired in a short period of time.

[0068] Next, the control parameter adjuster 950 obtains the control parameter by optimization calculation using the acquired closed loop response characteristic (Step S12). Herein, as shown in FIG. 1OB, the control parameter adjuster 950 acquires the load response and the command value and obtains the control parameter corresponding to the response sensitivity by optimization calculation based on the load response and the command value. In the present embodiment, the optimization calculation is performed online by using Gradient method (for example, BFGS algorithm) based on quasi-Newton method.

[0069] The optimization calculation performed by the control parameter adjuster 950 can be performed online and offline. For example, adjusting the control parameter may be performed offline at the time of initial start or restart of the crusher 1 and may be performed online at any timing during the operation of the crusher 1. The control parameter adjuster 950 can calculate a presently optimal parameter and reflect the parameter on the crushing load control.

[0070] Next, for verification, the control parameter adjuster 950 acquires the load response as the closed loop response characteristic by using the calculated control parameter (Step S13). Herein, as shown in FIG. 10C, the control parameter adjuster 950 sets the obtained control parameter in the feedback controlling circuitry 920 and gives a step excitation signal to the load target value. The feedback controlling circuitry 920 generates a command value based on the excitation signal and outputs the command value to the operation control circuitry 90. The load response acquirer 94 acquires the unprocessed load response as the closed loop response. The preprocessor 97 preprocesses the acquired unprocessed load response to obtain the load response. The control parameter adjuster 950 acquires this load response as the closed loop response characteristic for verification.

[0071] Finally, the control parameter adjuster 950 obtains a deviation between the closed loop response characteristic for verification and a given ideal response characteristic (Step S14). When the deviation is a given threshold or less, the control parameter adjuster 950 determines that the obtained control parameter is appropriate. Then, the control parameter adjuster 950 terminates the adjustment of the control parameter. In contrast, when the deviation exceeds the given threshold, the control parameter adjuster 950 determines that the obtained control parameter is not appropriate. Then, the control parameter adjuster 950 returns to Step S12.

[0072] The foregoing has described the method of adjusting the initial control parameter of the feedback controlling circuitry 920. Even when restarting the operation of the crusher 1, the control parameter of the feedback controlling circuitry 920 can be adjusted by the same procedure. In this case, the control circuitry 9 may store the control parameters and the obtained load response characteristics every time, and changes in the load response characteristics may be displayed on the display outputter 98 connected to the control circuitry 9 such that the load response characteristic obtained by the previous adjustment of the control parameter can be compared with the load response characteristic obtained this time. Specifically, the display controlling circuitry 93 outputs display information to the display outputter 98 such that one latest combination of the value of the control parameter adjusted by the control parameter adjuster 950 and the load response obtained based on this value is displayed on a screen image of the display outputter 98 together with at least one past combination thereof before the latest combination. The display outputter 98 which has acquired this display information displays the latest combination of the value of the control parameter and the load response obtained based on this value and at least one past combination of the value of the control parameter and the load response obtained based on this value before the latest combination. The load response characteristic includes information, such as a time, the unprocessed load response, and the load response. In addition to the load response, the time and the unprocessed load response may be displayed on the screen image of the display outputter 98. With this, the operation status of the crusher 1 as a result of the automatic adjustment of the control parameter can be informed to the operator. When the satisfactory load response is not obtained within the predetermined observation period in the adjustment of the control parameter this time, the control parameter adjuster 950 may return the value of the control parameter to the previously adjusted value of the control parameter.

[0073] Conclusion As described above, crushing load control circuitry 91 of a crusher 1 according to the present embodiment includes: a load response acquirer 94 that acquires, as an unprocessed load response, a crushing load obtained as a response of a command value that is output with respect to a control target of the crusher 1; a preprocessor 97 that preprocesses the unprocessed load response to obtain a load response; feedback controlling circuitry 92, 920 that generates a new command value based on a deviation between the load response and a predetermined load target value; and a control parameter adjuster 95, 950 that adjusts a control parameter of the feedback controlling circuitry 92, 920 based on the load response. The preprocessor 97 includes a steady characteristic extraction filter 97b that attenuates crush vibration which is included in the unprocessed load response and is specific to the crusher 1.

[0074] In the present embodiment, the crusher 1 is a gyratory crusher including: a conical tubular concave 14; a truncated conical mantle 13 located inside the concave 14; an electric motor 8 that makes the mantle 13 perform eccentric gyratory motion; a hopper 2 that feeds raw stones to a crushing chamber 16 located between the concave 14 and the mantle 13; a supplier 4 that supplies the raw stones to the hopper 2; a load measurer that measures a load index that directly or indirectly indicates the crushing load; and an outlet set adjuster 10 that changes an outlet set amount between the concave 14 and the mantle 13. The control target is any one of a supply amount of raw stones supplied by the supplier 4 and the outlet set amount changed by the outlet set adjuster 10.

[0075] According to the crushing load control circuitry 91 of the crusher 1 configured as above, the load response input to the feedback controlling circuitry 92 and the control parameter adjuster 95 is dominated by the processing performed by the preprocessor. To be specific, the load response from which influence of the crush vibration has been eliminated by the preprocessing can be regarded as the load response characteristic of the crusher 1. Since the filter characteristic of the preprocessor 97 can be designed arbitrarily, the control parameter adjuster 95 can be designed in accordance with the filter characteristic. With this, the automatic adjustment of the control parameter of the feedback controlling circuitry 92 can be theoretically performed by using the control parameter adjuster 95. Therefore, the work time and manpower required to adjust the control parameter can be reduced. Moreover, the accuracy of the determination regarding whether or not the adjustment of the control parameter is required can be improved.

[0076] Moreover, a method of controlling a load of a crusher 1 according to the present embodiment includes: acquiring, as an unprocessed load response, a crushing load obtained as a response of a command value that is output with respect to a control target of the crusher 1; preprocessing the unprocessed load response; generating a new command value by using a feedback controller (feedback controlling circuitry 92) based on a deviation between a load response obtained by preprocessing the unprocessed load response and a predetermined load target value; and adjusting a control parameter of the feedback controller based on the load response. The preprocessing step includes: attenuating crush vibration which is included in the unprocessed load response and is specific to the crusher; and extracting a steady characteristic from the unprocessed load response.

[0077] According to the method of controlling the crushing load of the crusher 1, the load response utilized in the step of generating the new command value and the step of adjusting the control parameter is dominated by the preprocessing. To be specific, the load response from which influence of the crush vibration has been eliminated by the preprocessing can be regarded as the load response characteristic of the crusher 1. Since the details of the processing of extracting the steady characteristic from the unprocessed load response in the preprocessing can be designed arbitrarily, the processing of adjusting the control parameter can be designed in accordance with the preprocessing. With this, the automatic adjustment of the control parameter of the feedback controller (feedback controlling circuitry 92) can be theoretically performed. Therefore, the work time and manpower required to adjust the control parameter can be reduced. Moreover, the accuracy of the determination regarding whether or not the adjustment of the control parameter is required can be improved. This can contribute to the continuation of the stable operation of the crusher.

[0078] In the crushing load control circuitry 91 according to the above embodiment, the steady characteristic extraction filter 97b is a low-pass filter that attenuates a frequency component whose frequency is not less than a cutoff frequency that is a minimum frequency of the crush vibration.

[0079] The unprocessed load response is preprocessed by the steady characteristic extraction filter 97b having the cutoff frequency that is adequately lower than the frequency (natural vibration frequency) of the crush vibration specific to the crusher 1. With this, the load response obtained by the preprocessing has a known characteristic that depends on the steady characteristic extraction filter 97b. Since the filter characteristic of the steady characteristic extraction filter 97b can be designed arbitrarily, a stability limit (i.e., a frequency band in which the hunting occurs) in the load response can be set.

[0080] Moreover, in the crushing load control circuitry 91 according to the above embodiment, the preprocessor 97 includes a noise elimination filter 97a that attenuates high frequency noise by moving average. Similarly, in the method of controlling the crushing load according to the above embodiment, the preprocessing step includes attenuating high-frequency noise of the unprocessed load response.

[0081] When the system changes in the crusher 1, its response steeply appears in the load index I. However, the necessity of sensitively responding to this is low. Sensitively responding to this is not preferable from the viewpoint of the protection of the actuator. Therefore, the preprocessor 97 configured as above is suitable for the characteristic of the crusher 1 in which response is fast but control may be slow.

[0082] Moreover, in the crushing load control circuitry 91 according to the above embodiment, the control parameter adjuster 95 according to First Example performs FFT frequency analysis of the load response, and when a peak of a known hunting frequency is detected in an analytical result of the FFT frequency analysis, the control parameter adjuster 95 estimates an increase in response sensitivity. Furthermore, when the control parameter adjuster 95 estimates the increase in the response sensitivity, the control parameter adjuster 95 obtains an amplitude of hunting included in the load response. When the amplitude is a predetermined first threshold or more, the control parameter adjuster 95 adjusts the control parameter such that a control gain as the control parameter decreases.

[0083] Similarly, the step of adjusting the control parameter according to the above embodiment includes: performing FFT frequency analysis of the load response; and estimating an increase in response sensitivity when a peak of a known hunting frequency is detected in an analytical result of the FFT frequency analysis. Moreover, the step of adjusting the control parameter includes: when the increase in the response sensitivity is estimated, obtaining an amplitude of hunting included in the load response; and when the amplitude is a predetermined first threshold or more, adjusting the control parameter such that a control gain as the control parameter decreases.

[0084] As above, the FFT frequency analysis is performed with respect to the load response from which the influence of the crush vibration has been eliminated. With this, the increase in the response sensitivity can be estimated with a high degree of accuracy by the detection of the peak of the hunting frequency. Then, the control parameter is adjusted in accordance with the increase in the response sensitivity estimated as above. Therefore, the response sensitivity significantly changes in the crusher 1, but the crushing load is controlled, and the stable operation can be continued.

[0085] Moreover, in the crushing load control circuitry 91 according to the above embodiment, when the peak of the hunting frequency is not detected in the FFT analysis result of the load response, and a peak of a frequency smaller than the hunting frequency is detected, the control parameter adjuster 95 according to First Example estimates a decrease in the response sensitivity. Furthermore, when the control parameter adjuster 95 estimates the decrease in the response sensitivity, the control parameter adjuster 95 obtains a deviation area by accumulating a deviation between the load target value and the load response for a predetermined period of time. When the deviation area is a predetermined second threshold or more, the control parameter adjuster 95 adjusts the control parameter such that a control gain as the control parameter increases.

[0086] Similarly, in the method of controlling the crushing load according to the above embodiment, the step of adjusting the control parameter includes estimating a decrease in the response sensitivity when the peak of the hunting frequency is not detected in the analytical result, and a peak of a frequency smaller than the hunting frequency is detected. Furthermore, the step of adjusting the control parameter includes: when the decrease in the response sensitivity is estimated, obtaining a deviation area by accumulating a deviation between the load target value and the load response for a predetermined period of time; and when the deviation area is a predetermined second threshold or more, adjusting the control parameter such that a control gain as the control parameter increases.

[0087] As above, the FFT frequency analysis is performed with respect to the load response from which the influence of the crush vibration has been eliminated. With this, the decrease in the response sensitivity can be estimated with a high degree of accuracy by the detection of the peak of the frequency smaller than the hunting frequency. Then, the control parameter is adjusted in accordance with the decrease in the response sensitivity estimated as above. Therefore, the response sensitivity significantly changes in the crusher 1, but the crushing load is controlled, and the stable operation can be continued.

[0088] Moreover, in the crushing load control circuitry 91 according to the above embodiment, when a change in response sensitivity is continuously estimated even after a predetermined observation period has elapsed since the adjustment of the control parameter, the control parameter adjuster 95 according to First Example outputs an alarm to inform an operator of abnormality.

[0089] Similarly, in the method of adjusting the crushing load according to the above embodiment, the step of adjusting the control parameter includes outputting an alarm to inform an operator of abnormality when a change in response sensitivity is continuously estimated even after a predetermined observation period has elapsed since the adjustment of the control parameter.

[0090] Moreover, in the crushing load control circuitry 91 according to the above embodiment, the control parameter adjuster 950 according to Second Example performs data driven controller tuning (fictitious reference iterative tuning; FRIT). Herein, the crushing load control circuitry 91 may further include display controlling circuitry 93 that outputs display information such that one latest combination of a value of the control parameter adjusted by the control parameter adjuster 950 and the load response obtained based on this value is displayed together with at least one past combination thereof before the latest combination.

[0091] Similarly, in Second Example of the above embodiment, the step of adjusting the control parameter includes performing data-driven controller tuning (fictitious reference iterative tuning; FRIT) of the control parameter. Herein, the step of adjusting the control parameter may include performing output such that one latest combination of a value of the adjusted control parameter and the load response obtained based on this value is displayed together with at least one past combination thereof before the latest combination.

[0092] By using the FRIT to adjust the control parameter as above, manpower required to adjust the initial control parameter (at the time of the initial start or the restart), which has conventionally been adjusted by trial and error in an actual device test, can be reduced. In addition, a time required for the work can be reduced.

[0093] The foregoing has described the preferred embodiment. Modifications of specific structures and/or functional details of the above embodiment may be included in the present disclosure as long as they are within the scope of the present disclosure. The above configuration may be modified as below, for example.

[0094] For example, in the above embodiment, the crusher 1 includes the outlet set adjuster 10 that is a hydraulic type. However, the crushing load control of the crushing load control circuitry 91 may be applied to a mechanical crusher including a mechanical outlet set adjuster. However, according to the mechanical crusher, the outlet set adjuster needs to be fixed by pressure during the crushing operation. On this account, it is difficult to change the outlet set amount during the crushing operation, and therefore, the supply amount of the supplier 4 is adopted as the control target.

[0095] For example, in the above embodiment, the control parameter of the feedback controlling circuitry 92, 920 is adjusted online but may be adjusted offline.

[0096] Moreover, in the above embodiment, the combination of the crushing load control of First Example and the crushing load control of Second Example may be applied to one crusher 1.

For example, the control parameter may be adjusted based on Second Example at the time of the initial start and restart of the crusher 1, and the control parameter may be adjusted based on First Example during the steady operation of the crusher 1.

[0097] Moreover, in the above embodiment, the crusher 1 is the gyratory crusher. However, the crusher 1 to which the present disclosure is applied is not limited to the gyratory crusher and may be a crusher in which control speed may be relatively low. Examples of such crusher include: a uniaxial shearing crusher utilized to crush waste and the like; and an impact crusher utilized to crush rocks, ores, and the like.

[0098] Moreover, in the above embodiment, the crusher 1 automatically changes the feed amount of raw stones or the outlet set amount in accordance with a command from the crushing load control circuitry 91. However, the feed amount of raw stones and the outlet set amount may be changed manually by the operator. In this case, it is desirable that the control circuitry 9 make the display outputter 98 display the state of the load response and the command (i.e., the operation amount or its adjustment value) from the crushing load control circuitry 91.

Reference Signs List

[0099] 1 crusher 2 hopper 4 supplier 8 electric motor 10 outlet set adjuster 13 mantle 14 concave 16 crushing chamber 9 control circuitry 90 operation control circuitry 91 crushing load control circuitry 92,920 feedback controlling circuitry (feedback controller) 93 display controlling circuitry 94 load response acquirer 93 display controlling circuitry 95,950 control parameter adjuster 97 preprocessor 97a noise elimination filter

97b steady characteristic extraction filter

Claims (20)

1. CLAIMS 1. Crushing load control circuitry of a crusher, the crushing load control circuitry including: a load response acquirer that acquires, as an unprocessed load response, a crushing load obtained as a response of a command value that is output with respect to a control target of the crusher; a preprocessor that preprocesses the unprocessed load response to obtain a load response; feedback controlling circuitry that generates a new command value based on a deviation between the load response and a predetermined load target value; and a control parameter adjuster that adjusts a control parameter of the feedback controlling circuitry based on the load response, wherein the preprocessor includes a steady characteristic extraction filter that attenuates crush vibration which is included in the unprocessed load response and is specific to the crusher.
2. 2. The crushing load control circuitry according to claim 1, wherein the steady characteristic extraction filter is a low-pass filter that attenuates a frequency component whose frequency is not less than a cutoff frequency that is a minimum frequency of the crush vibration.
3. 3. The crushing load control circuitry according to claim 1 or 2, wherein the preprocessor includes a noise elimination filter that attenuates high-frequency noise.
4. 4. The crushing load control circuitry according to any one of claims 1 to 3, wherein: the control parameter adjuster performs FFT frequency analysis of the load response; and when a peak of a known hunting frequency is detected in an analytical result of the FFT frequency analysis, the control parameter adjuster estimates an increase in response sensitivity.
5. 5. The crushing load control circuitry according to claim 4, wherein: when the control parameter adjuster estimates the increase in the response sensitivity, the control parameter adjuster obtains an amplitude of hunting included in the load response; and when the amplitude is a predetermined first threshold or more, the control parameter adjuster adjusts the control parameter such that a control gain as the control parameter decreases.
6. 6. The crushing load control circuitry according to claim 4 or 5, wherein when the peak of the hunting frequency is not detected in the analytical result, and a peak of a frequency smaller than the hunting frequency is detected, the control parameter adjuster estimates a decrease in the response sensitivity.
7. 7. The crushing load control circuitry according to claim 6, wherein: when the control parameter adjuster estimates the decrease in the response sensitivity, the control parameter adjuster obtains a deviation area by accumulating a deviation between the load target value and the load response for a predetermined period of time; and when the deviation area is a predetermined second threshold or more, the control parameter adjuster adjusts the control parameter such that a control gain as the control parameter increases.
8. 8. The crushing load control circuitry according to any one of claims 4 to 7, wherein when a change in response sensitivity is continuously estimated even after a predetermined observation period has elapsed since the adjustment of the control parameter, the control parameter adjuster outputs an alarm to inform an operator of abnormality.
9. 9. The crushing load control circuitry according to any one of claims 1 to 3, wherein the control parameter adjuster performs data-driven controller tuning (fictitious reference iterative tuning; FRIT).
10. 10. The crushing load control circuitry according to claim 9, further including display controlling circuitry that outputs display information such that one latest combination of a value of the control parameter adjusted by the control parameter adjuster and the load response obtained based on this value is displayed together with at least one past combination thereof before the latest combination.
11. 11. The crushing load control circuitry according to any one of claims 1 to 10, wherein: the crusher is a gyratory crusher including a conical tubular concave, a truncated conical mantle located inside the concave, an electric motor that makes the mantle perform eccentric gyratory motion, a hopper that feeds raw stones to a crushing chamber located between the concave and the mantle, a supplier that supplies the raw stones to the hopper, a load measurer that measures a load index that directly or indirectly indicates the crushing load, and an outlet set adjuster that changes an outlet set amount between the concave and the mantle; and the control target is one of a supply amount of raw stones supplied by the supplier and the outlet set amount changed by the outlet set adjuster.
12. 12. A method of controlling a crushing load of a crusher, the method including: acquiring, as an unprocessed load response, a crushing load obtained as a response of a command value that is output with respect to a control target of the crusher; preprocessing the unprocessed load response; generating a new command value by using a feedback controller based on a deviation between a load response obtained by preprocessing the unprocessed load response and a predetermined load target value; and adjusting a control parameter of the feedback controller based on the load response, wherein the preprocessing step includes attenuating crush vibration which is included in the unprocessed load response and is specific to the crusher, and extracting a steady characteristic from the unprocessed load response.
13. 13. The method according to claim 12, wherein the preprocessing step includes attenuating high-frequency noise of the unprocessed load response.
14. 14. The method according to claim 12 or 13, wherein the step of adjusting the control parameter includes: performing FFT frequency analysis of the load response; and estimating an increase in response sensitivity when a peak of a known hunting frequency is detected in an analytical result of the FFT frequency analysis.
15. 15. The method according to claim 14, wherein the step of adjusting the control parameter includes: when the increase in the response sensitivity is estimated, obtaining an amplitude of hunting included in the load response; and when the amplitude is a predetermined first threshold or more, adjusting the control parameter such that a control gain as the control parameter decreases.
16. 16. The method according to claim 14 or 15, wherein the step of adjusting the control parameter includes estimating a decrease in the response sensitivity when the peak of the hunting frequency is not detected in the analytical result, and a peak of a frequency smaller than the hunting frequency is detected.
17. 17. The method according to claim 16, wherein the step of adjusting the control parameter includes: when the decrease in the response sensitivity is estimated, obtaining a deviation area by accumulating a deviation between the load target value and the load response for a predetermined period of time; and when the deviation area is a predetermined second threshold or more, adjusting the control parameter such that a control gain as the control parameter increases.
18. 18. The method according to any one of claims 14 to 17, wherein the step of adjusting the control parameter includes outputting an alarm to inform an operator of abnormality when a change in response sensitivity is continuously estimated even after a predetermined observation period has elapsed since the adjustment of the control parameter.
19. 19. The method according to claim 12 or 13, wherein the step of adjusting the control parameter includes performing data-driven controller tuning (fictitious reference iterative tuning; FRIT) of the control parameter.
20. 20. The method according to claim 19, wherein the step of adjusting the control parameter includes performing output such that one latest combination of a value of the adjusted control parameter and the load response obtained based on this value is displayed together with at least one past combination thereof before the latest combination.