Gyratory crusher, control device thereof, and method of controlling gyratory crusher

Abstract

A gyratory crusher includes: a set sensor that detects a set between a mantle and a concave; a hydraulic circuit that includes an accumulator and generates cylinder hydraulic pressure, which changes the set, in a hydraulic chamber; and a crushing load detector that detects a crushing load. A control device of the gyratory crusher includes: a load stabilization controller that generates a set target value by which the crushing load is controlled to become a predetermined crushing load target value; a set controller that operates the hydraulic circuit to control the set such that the set becomes the set target value; and an overload detector that calculates a set variation index indicating a degree of sudden increase of the set and detects an abnormal increase of the crushing load on the basis that the set variation index has exceeded a predetermined set threshold.

Description

Rotating crusher and its control device and control method

[0001] The present disclosure relates to a gyro crusher, and a control device and control method for a gyro crusher.

[0002] Conventionally, a rotating crusher has been known in which a crushing chamber is formed between a conical cylindrical concave and a truncated conical mantle placed inside the concave, and raw material supplied from a raw material hopper to the crushing chamber is pinched between the concave and the mantle to crush it. The mantle is driven by an electric motor to rotate eccentrically. The gap between the two crushing surfaces of the concave and the mantle periodically changes, and the particle size of the crushed material is determined by the value of the set (i.e., opening) of the gap. Rotating crushers are classified into hydraulic and mechanical types depending on the method of changing the set. Hydraulic types have a hydraulic cylinder that raises and lowers the mantle relative to a fixed concave. Mechanical types have an electric motor that raises and lowers the concave relative to the mantle.

[0003] Patent Document 1 discloses a hydraulic gyratory crusher. In this gyratory crusher, a main shaft connected to a mantle is supported by a ram of a hydraulic cylinder, and the set is changed by raising and lowering the ram using hydraulic force. If the crushing cavity between the concave and the mantle becomes overloaded due to the inclusion of uncrushable foreign matter or a temporary increase in the amount of raw material input, the hydraulic cylinder and accumulator are automatically connected, and hydraulic oil in the cylinder is released into the accumulator, causing the mantle to descend and expanding the set of the crushing cavity, thereby alleviating the overload.

[0004] Special Publication No. 2009-511254

[0005] As described above, when the crushing load suddenly fluctuates, the accumulator automatically operates to maintain pressure balance. Therefore, if the operator continues to operate the crusher without understanding the fluctuations in the crushing load, the poppet valve at the inlet of the accumulator will frequently open and close repeatedly, resulting in a so-called tapping phenomenon. The tapping phenomenon accelerates wear on the poppet valve, accelerates fatigue of the bags that repeatedly expand and contract in the accumulator, and also accelerates wear on the mechanical parts of the crusher. If a sudden increase in the crushing load can be detected, the continuation of the tapping phenomenon can be prevented by operating the accumulator and taking measures to eliminate the overload.

[0006] The present disclosure has been made in consideration of the above circumstances, and its purpose is to propose a technology for detecting a sudden increase in crushing load in a hydraulic gyratory crusher without requiring the addition of new equipment.

[0007] A control device for a gyratory crusher according to one aspect of the present disclosure is a control device for a gyratory crusher comprising: a main shaft, a mantle fixed to the main shaft, a concave arranged opposite the mantle and forming a crushing chamber between the mantle and the concave, a set sensor for detecting a set between the mantle and the concave, a hydraulic cylinder supporting the main shaft, a hydraulic circuit having an accumulator connected to the hydraulic chamber of the hydraulic cylinder and generating cylinder oil pressure that changes the set in the hydraulic chamber, and a crushing load detector for detecting a crushing load, and comprising: a load stabilization control unit that generates a set target value that controls the crushing load to a predetermined crushing load target value; a set control unit that operates the hydraulic circuit to control the set to the set target value; and a load abnormality detection unit that calculates a set fluctuation index that indicates the degree of sudden increase in the set, and detects an abnormal increase in the crushing load based on the set fluctuation index exceeding a predetermined set threshold.

[0008] A gyratory crusher according to one aspect of the present disclosure includes a main shaft, a mantle fixed to the main shaft, a concave arranged to face the mantle and forming a crushing chamber between the mantle and the concave, a set sensor that detects a set between the mantle and the concave, a hydraulic cylinder that supports a lower part of the main shaft, a hydraulic circuit that has an accumulator connected to the hydraulic chamber of the hydraulic cylinder and generates cylinder oil pressure that changes the set in the hydraulic chamber, a crushing load detector that detects a crushing load, and a control device for the gyratory crusher.

[0009] A control method for a gyratory crusher according to one aspect of the present disclosure is a control method for a gyratory crusher including: a main shaft; a mantle fixed to the main shaft; a concave disposed opposite the mantle and forming a crushing chamber between the mantle and the concave; a set sensor for detecting a set between the mantle and the concave; a hydraulic cylinder supporting the main shaft; a hydraulic circuit having an accumulator connected to a hydraulic chamber of the hydraulic cylinder and generating a cylinder oil pressure that changes the set in the hydraulic chamber; and a crushing load detector for detecting a crushing load, the control method comprising: acquiring a detected value of the crushing load, and generating a set target value that controls the crushing load to a predetermined crushing load target value; operating the hydraulic circuit to control the set to the set target value; and acquiring the detected value of the set, determining a set fluctuation index that indicates the degree of sudden increase in the set, and detecting an abnormal increase in the crushing load based on the set fluctuation index exceeding a predetermined set threshold value.

[0010] According to the present disclosure, in a hydraulic gyratory crusher, a sudden increase in crushing load can be detected without the need to add any new equipment.

[0011] Fig. 1 is a diagram showing a schematic configuration of a gyrating crusher according to one embodiment of the present disclosure. Fig. 2 is a block diagram showing the configuration of a control system of the crusher. Fig. 3 is a diagram explaining the functional parts of a control device of the crusher. Fig. 4 is a diagram showing the configuration of a hydraulic system of a hydraulic cylinder. Fig. 5 is a timing chart of control of the crushing load.

[0012] Next, an embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a diagram showing a schematic configuration of a gyratory crusher 100 according to one embodiment of the present disclosure. The gyratory crusher 100 shown in Fig. 1 is a gyratory crusher or a cone crusher, and the configuration of the crusher 100 itself, excluding the control device 50, is known.

[0013] The gyro crusher 100 has a frame 30 consisting of an upper frame 31 and a lower frame 32 connected thereto. A machine body central axis A extending vertically is defined in the center of the internal space of the frame 30. A hopper 3 is connected to the upper part of the frame 30. Raw materials to be crushed are supplied to the hopper 3 from a supply device 9 (e.g., a conveyor).

[0014] The main shaft 5 is disposed approximately in the center of the frame 30. The central axis of the main shaft 5 is inclined with respect to the machine body central axis A. The upper end of the main shaft 5 is supported by the upper frame 31 via an upper bearing 17. The upper bearing 17 is attached to a spider 18 that protrudes inward from the upper end of the upper frame 31. The lower end of the main shaft 5 is supported by the ram 61 of the hydraulic cylinder 6 via a main shaft thrust bearing 2. The hydraulic cylinder 6 is a bearing cylinder consisting of a cylinder tube 62 and the ram 61 that slides within the cylinder tube 62.

[0015] The lower part of the main shaft 5 is rotatably inserted into the eccentric sleeve 4. The eccentric sleeve 4 is rotatably inserted into a boss 7 formed on the lower frame 32. The lower part of the eccentric sleeve 4 is supported by the lower frame 32 via a thrust sliding bearing 23.

[0016] A mantle core 12 is fixed to the upper part of the main shaft 5. The outer surface of the mantle core 12 is a frusto-conical surface. A mantle 13 is attached to the outer surface of the mantle core 12. The outer surface of the mantle 13 is also a frusto-conical surface. The outer surface of the mantle 13 faces the inner surface of a concave 14 provided on the inner surface of the upper frame 31. The inner surface of the concave 14 and the outer surface of the mantle 13 form a crushing chamber 16 having a wedge-shaped vertical cross section. The raw material supplied to the hopper 3 flows into the crushing chamber 16 by its own weight.

[0017] A cylindrical partition plate 24 is provided above the boss 7. This partition plate 24 forms a hydraulic chamber 27 above the eccentric sleeve 4 and boss 7 and below the mantle core 12. Lubricant is supplied from this hydraulic chamber 27 between the outer peripheral surface of the main shaft 5 and the inner peripheral surface of the eccentric sleeve 4, and between the outer peripheral surface of the eccentric sleeve 4 and the inner peripheral surface of the boss 7. The journal plain bearing formed between the outer peripheral surface of the main shaft 5 and the inner peripheral surface of the eccentric sleeve 4 is referred to as the "main shaft bearing 10," and the journal plain bearing formed between the outer peripheral surface of the eccentric sleeve 4 and the inner peripheral surface of the boss 7 is referred to as the "sleeve bearing 11." The multiple bearing formed by the main shaft bearing 10 and the sleeve bearing 11 is referred to as the "lower bearing 15."

[0018] A drive motor 8 is disposed outside the frame 30. Power is transmitted from the output shaft 8a of the drive motor 8 to the eccentric sleeve 4 via a power transmission mechanism 20. The power transmission mechanism 20 includes a pulley 22a provided on the output shaft 8a, a horizontal shaft 21, a pulley 22b provided on the horizontal shaft 21, a power transmission belt 22c wound around the pulleys 22a and 22b, a bevel pinion 19a provided on the horizontal shaft 21, and a bevel gear 19b provided on the eccentric sleeve 4. The horizontal shaft 21 is supported by the lower frame 32 via a horizontal shaft bearing 25. When the eccentric sleeve 4 rotates, the main shaft 5 performs a revolving motion eccentric to the aircraft central axis A, known as precession. As a result, the distance between the outer surface of the mantle 13 and the inner surface of the concave 14 changes depending on the revolving position of the main shaft 5. The raw material that has fallen into the crushing chamber 16 is crushed between the concave 14 and the mantle 13 and is recovered as crushed material from below the lower frame 32.

[0019] [Control device 50] The crusher 100 configured as described above includes a control device 50. The control device 50 is not necessarily arranged in close proximity to the components of the crusher 100 other than the control device 50, and may be arranged away from the components of the crusher 100 other than the control device 50. For example, the control device 50 may be configured on a network server, and the control device 50 may control each element of the crusher 100 via the network.

[0020] FIG. 2 is a block diagram showing the configuration of the control system of the crusher 100. As shown in FIG. 2, the control device 50 is connected to a display device 58, a setting device 59, various meters 52, 55, and 56, and controlled objects 8, 9a, and 90. The functions of the control device 50 disclosed herein can be performed using circuits or processing circuits, including general-purpose processors, dedicated processors, integrated circuits, ASICs (Application Specific Integrated Circuits), conventional circuits, and / or combinations thereof, configured or programmed to perform the disclosed functions. Because processors include transistors and other circuits, they are considered processing circuits or circuits. In this disclosure, circuits, units, or means are hardware that performs the enumerated functions. The hardware may be hardware disclosed herein or other known hardware that is programmed or configured to perform the enumerated functions. Where hardware is a processor, which is considered a type of circuit, the circuit, means, or unit is a combination of hardware and software, and software is used to configure the hardware and / or processor.

[0021] Fig. 3 is a diagram illustrating the functional units of the control device 50. As shown in Fig. 3, the control device 50 includes the following functional units: a supply control unit 81, a rotation control unit 82, a set control unit 83, a load stabilization control unit 84, a load abnormality detection unit 85, and an overload resolution control unit 86.

[0022] The supply control unit 81 of the control device 50 controls the amount of raw material supplied by the supply device 9. The control device 50 is connected wirelessly or by wire to the drive motor 9a of the supply device 9. The control device 50 transmits a command signal corresponding to a target supply amount to the drive motor 9a of the supply device 9. The drive motor 9a operates in response to the command signal from the control device 50, thereby supplying the target supply amount of raw material from the supply device 9 to the hopper 3.

[0023] The rotation control unit 82 of the control device 50 controls the rotation speed of the eccentric sleeve 4. The rotation speed of the eccentric sleeve 4 corresponds to the rotation speed of the horizontal shaft 21, which is driven to rotate by the drive motor 8, and the rotation speed of the main shaft 5. The control device 50 is connected to the drive motor 8 wirelessly or via a wire. A current sensor 56, which detects the drive current of the drive motor 8, is also connected to the control device 50. The control device 50 transmits a command signal corresponding to the target rotation speed to the drive motor 8. The drive motor 8 operates in response to the command signal from the control device 50, so that the rotation speed of the eccentric sleeve 4 becomes the target rotation speed.

[0024] The set control unit 83 of the control device 50 controls the "set," which is the dimension of the crushing gap between the two crushing surfaces, the concave 14 and the mantle 13, to a set target value. In this embodiment, the set is the size of the gap at the narrowest position of the crushing gap, i.e., the CSS (Closed Side Setting). In the crusher 100 according to this embodiment, the hydraulic cylinder 6 functions as a set adjustment device. When the main shaft thrust bearing 2 moves up and down together with the ram 61, the mantle 13 moves up and down relative to the concave 14, changing the set dimension. The set dimension determines the particle size of the crushed material. The control device 50 is connected wirelessly or by wire to a set sensor 52 that detects the set. The set sensor 52 is, for example, a displacement sensor that detects the displacement of the ram 61.

[0025] Figure 4 is a diagram showing the configuration of the hydraulic system of the hydraulic cylinder 6. As shown in Figure 4, a hydraulic chamber 63 whose capacity changes depending on the displacement of the ram 61 is formed inside the cylinder tube 62 of the hydraulic cylinder 6, and a hydraulic circuit 90 is connected to this hydraulic chamber 63. The ram 61 rises when hydraulic oil from the oil tank 71 is supplied to the hydraulic chamber 63 through the hydraulic circuit 90. The ram 61 descends when hydraulic oil from the hydraulic chamber 63 is drained to the oil tank 71 through the hydraulic circuit 90.

[0026] The hydraulic circuit 90 may have any configuration, but is exemplified as follows. The hydraulic circuit 90 includes a communicating pipe 91 connected to the lower portion of the hydraulic chamber 63, an accumulator 92 connected to the communicating pipe 91, an oil supply pipe 93 connected to the communicating pipe 91, and an oil drain pipe 94 connected to the oil supply pipe 93. A poppet valve 92a is provided at the inlet and outlet of the accumulator 92, and the opening and closing of the poppet valve 92a switches between allowing and blocking the flow of hydraulic oil into and out of the accumulator 92. The communicating pipe 91 is provided with a hydraulic sensor 55 that detects the pressure of the hydraulic oil in the hydraulic chamber 63. The oil supply pipe 93 is provided with a gear pump 76 that pumps hydraulic oil from the oil tank 71 to the hydraulic chamber 63. The gear pump 76 is driven by a pump motor 77. A normally closed on-off valve 98 is provided in the oil supply pipe 93. A normally closed on-off valve 99 is provided in the oil drain pipe 94.

[0027] The load stabilization control unit 84 of the control device 50 performs load stabilization control to stabilize the crushing load at a given crushing load target value. The load stabilization control unit 84 acquires the crushing load detected by the crushing load detector. The crushing load refers to the load applied to the moving parts of the crusher 100 due to crushing. In this embodiment, the "cylinder oil pressure," which is the hydraulic oil pressure of the hydraulic cylinder 6 detected by the oil pressure sensor 55, or the "drive current" of the drive motor 8 detected by the current sensor 56 is used as an indicator of the crushing load. When the cylinder oil pressure is used as the indicator of the crushing load, the oil pressure sensor 55 is the crushing load detector, and the load stabilization control unit 84 acquires the cylinder oil pressure from the oil pressure sensor 55. When the drive current of the drive motor 8 is used as the indicator of the crushing load, the current sensor 56 is the crushing load detector, and the load stabilization control unit 84 acquires the current value from the current sensor 56.

[0028] The load stabilization control unit 84 generates a set target value that controls the crushing load to a predetermined crushing load target value. Specifically, the load stabilization control unit 84 generates a crushing load command value that changes the set so that the set is expanded if the detected crushing load is higher than the crushing load target value, and is reduced if the detected crushing load is lower than the crushing load target value. The crushing load command value generated by the load stabilization control unit 84 is limited to a level that does not cause a sudden change in the current crushing load. Note that, in order to control the crushing load to the predetermined crushing load target value, the set target value is adjusted in stages. For example, a new set target value is generated by adding or subtracting a predetermined set adjustment amount to or from the current set target value, and this process is repeated until the crushing load reaches the crushing load target value.

[0029] The set control unit 83 operates the hydraulic circuit 90 of the hydraulic cylinder 6 to control the set to a set target value. The set control unit 83 acquires an actual measurement value of the set detected by the set sensor 52 (hereinafter referred to as the "set detection value"), determines the operation amount of the ram 61 based on the difference between the set detection value and the set target value, and generates an operation command for the hydraulic circuit 90 based on the operation amount. More specifically, the set control unit 83 generates operation commands for control elements of the hydraulic circuit 90, such as the pump motor 77, the on-off valve 98, and the on-off valve 99. When the hydraulic circuit 90 operates in response to this operation command, a cylinder oil pressure is generated in the hydraulic chamber 63 of the hydraulic cylinder 6 that displaces the ram 61 by the operation amount so that the set reaches the set target value.

[0030] During the load stabilization control, the crushing load may suddenly increase due to the introduction of uncrushable foreign matter into the crushing chamber 16, the occurrence of packing, or other momentary overload. Such a sudden increase in the crushing load is referred to herein as an "abnormal increase in the crushing load." The load abnormality detection unit 85 detects an abnormal increase in the crushing load.

[0031] The load abnormality detection unit 85 uses a "set fluctuation index" to detect an abnormal increase in the crushing load. The set fluctuation index is an index that indicates the degree of increase in sets when there is a sudden increase in sets. In this embodiment, the difference d between the set detection value and the moving average value of the set detection value is used as the set fluctuation index. The difference d indicates the degree of increase in sets. Furthermore, the difference d can be used to estimate whether the increase in sets is sudden or not.

[0032] The load abnormality detection unit 85 calculates a moving average value of the set detection value based on the set detection value acquired from the set sensor 52 and a predetermined moving average time. A moving average filter may be used to calculate the moving average value. The load abnormality detection unit 85 calculates a difference d between the set detection value and the moving average value of the set detection value, and monitors the difference d during operation of the crusher 100. The load abnormality detection unit 85 compares the difference d with a predetermined set threshold, and detects an abnormal increase in the crushing load when the difference d exceeds the set threshold. The set threshold and the moving average time are stored in advance in the control device 50, and the set detection value detected by the set sensor 52 is stored in the control device 50 in association with the detection time. The set threshold is set to a value greater than the difference d caused by a change in the set target value by the set adjustment amount due to load stabilization control.

[0033] The overload elimination control unit 86 performs overload elimination control when the load abnormality detection unit 85 detects an abnormal increase in the crushing load. The overload elimination control unit 86 generates a set target value so that the tapping phenomenon that has occurred is eliminated or so that the tapping phenomenon does not occur. During the overload elimination control, the set control unit 83 controls the set based on the set target value generated by the overload elimination control unit 86.

[0034] [Method of Controlling the Crusher 100] Here, a method of controlling the crusher 100 by the control device 50 will be described, focusing on the control of the crushing load. Fig. 5 is a timing chart of the control of the crushing load. In Fig. 5, (A) represents the set detection value detected by the set sensor 52, (B) represents the moving average value of the set detection value, (C) represents the difference d between the set detection value and the moving average value of the set detection value, (D) represents the on / off of the overload elimination control, and (E) represents the set target value.

[0035] As shown in the timing chart of FIG. 5, during a steady crushing load, the overload elimination control is off, and the crushing load is controlled by the load stabilization control unit 84. During a steady crushing load, the nitrogen gas pressure in the accumulator 92 is higher than the hydraulic pressure in the hydraulic cylinder 6, so hydraulic oil does not flow into the accumulator 92. However, when an abnormal increase in the crushing load occurs, as described above, the mantle 13 is pushed down, pushing the ram 61 of the hydraulic cylinder 6 supporting the main shaft 5 downward. As a result, the cylinder hydraulic pressure exceeds the nitrogen gas pressure, and hydraulic oil flows into the accumulator 92 through the hydraulic circuit 90. This operation of the accumulator 92 rapidly expands the set, facilitating the discharge of foreign matter from the crushing chamber 16. The increase in set at time T1 in the timing chart is due to the operation of the accumulator 92 in response to the abnormal increase in the crushing load. This sudden and rapid increase in set causes the difference d to increase.

[0036] The load abnormality detection unit 85 of the control device 50 monitors the difference d during operation of the crusher 100, and detects an abnormal increase in the crushing load when the difference d exceeds a set threshold value at time T2. Note that if the set increases slowly, the value of the difference d will not reach the set threshold value.

[0037] When an abnormal increase in the crushing load is detected, the overload elimination control is turned on, the overload elimination control section 86 of the control device 50 starts the overload elimination control, and the load stabilization control by the load stabilization control section 84 is temporarily stopped.

[0038] When the overload elimination control section 86 starts the overload elimination control, it first compares the set target value with a predetermined set reference value, and performs a first overload elimination control if the current set target value is equal to or greater than the set reference value, and performs a second overload elimination control if the current set target value is less than the set reference value. The set reference value is stored in advance in the control device 50.

[0039] (First Overload Resolution Control) The overload resolution control unit 86 resets the set target value to a predetermined set reference value. The set reference value is stored in advance in the control device 50. Next, the overload resolution control unit 86 generates a new set target value by adding a predetermined set addition value to the current set target value. The set control unit 83 controls the set using the new set target value. The set addition value is stored in advance in the control device 50. The set target value is adjusted in stages, and the generation of a new set target value is repeated until the set target value becomes equal to or less than the set detection value. This overload resolution control gradually reduces the difference d, and at time T3 when the difference d reaches a predetermined threshold, the off-delay timer begins timing. After the predetermined off-delay time has elapsed, the overload resolution control is turned off at time T4, and load stabilization control by the load stabilization control unit 84 is resumed.

[0040] The set addition value in the above-described overload resolution control is larger than the set adjustment amount in the load stabilization control, and as a result, the amount of change per step of the set target value is larger in the overload resolution control than in the load stabilization control, which allows the overload to be resolved quickly and the normal operation to be restored quickly.

[0041] (Second Overload Resolution Control) The overload resolution control unit 86 first sets a predetermined overload resolution target value as the set target value. The overload resolution target value is the maximum set detection value after the tapping phenomenon occurs due to an overload. However, the overload resolution target value is not limited to this and may be a value previously stored in the control device 50. Next, the overload resolution control unit 86 compares the current set target value (i.e., the maximum set detection value after the tapping phenomenon occurs) with the set detection value from a predetermined time ago (e.g., 0.5 seconds ago) and sets the larger of these as the new set target value. This overload resolution control gradually reduces the difference d, and the setting of a new set target value is repeated until the difference d reaches the set threshold value. The off-delay timer starts timing at time T3 when the difference d reaches the set threshold value. After the predetermined off-delay time has elapsed, the overload resolution control is turned off at time T4, and the load stabilization control by the load stabilization control unit 84 resumes.

[0042] According to the above-described overload elimination control (first and second overload elimination controls), the overload is quickly eliminated, so that the frequency of repeated activation and deactivation of the accumulator 92 is reduced, and tapping does not occur, or, if it does occur, it is quickly eliminated. In this way, the continuation of the tapping phenomenon is prevented compared to the conventional technique, and the lifespan of hydraulic components such as the accumulator 92 and poppet valve 92a, and mechanical components of the power transmission mechanism 20 can be extended.

[0043] In the above-described control method for the crusher 100, the load abnormality detection unit 85 uses the difference d between the detected set value and the moving average value of the detected set value as the set fluctuation index. However, the set fluctuation index is not limited to this, and may be any index that represents the degree of increase in the set when a sudden increase in the set occurs. For example, the set fluctuation index may be the increase per unit time of the difference between the set detected by the set sensor 52 (i.e., the detected set value) and the target set value. The increase per unit time of the difference between the detected set value and the target set value represents the degree of increase in the set. Furthermore, by using the difference between the detected set value and the target set value, it is possible to infer that the set has suddenly deviated from the target set value. When this set fluctuation index is used, load abnormalities can be detected in the same manner as in the above-described embodiment. That is, the load abnormality detection unit 85 is configured to acquire the set detection value detected by the set sensor 52 during operation of the crusher 100 and the set target value generated by the load stabilization control unit 84, calculate the increase per unit time of the difference between the set detection value and the set target value, and detect an abnormal increase in the crushing load if this increase exceeds a predetermined set threshold value.

[0044] In the above-described control method for the crusher 100, the load abnormality detection unit 85 detects an abnormal increase in the crushing load based on the set fluctuation index, but the abnormal increase in the crushing load may also be detected based on the set fluctuation index and the cylinder oil pressure. In this case, the load abnormality detection unit 85 is configured to detect an abnormal increase in the crushing load based on the fact that the set fluctuation index calculated from the set detection value detected by the set sensor 52 exceeds the set threshold value and the cylinder oil pressure detected by the oil pressure sensor 55 exceeds a predetermined oil pressure threshold value during operation of the crusher 100.

[0045] [Summary] The control device 50 for the gyro crusher 100 according to the first aspect of the present disclosure comprises: a main shaft 5; a mantle 13 fixed to the main shaft 5; a concave 14 arranged to face the mantle 13 and forming a crushing chamber 16 between the mantle 13; a set sensor 52 for detecting a set between the mantle 13 and the concave 14; a hydraulic cylinder 6 supporting the main shaft 5; a hydraulic circuit 90 having an accumulator 92 connected to the hydraulic chamber 63 of the hydraulic cylinder 6 and generating a cylinder oil pressure for changing the set in the hydraulic chamber 63; and crushing load detectors 55, 56 for detecting a crushing load, and further comprising: a load stabilization control unit 84 for generating a set target value for controlling the crushing load to a predetermined crushing load target value; a set control unit 83 for operating the hydraulic circuit 90 to control the set to the set target value; The apparatus is characterized by including a load abnormality detection unit 85 that calculates a set fluctuation index that indicates the degree of sudden increase in the set, and detects an abnormal increase in the crushing load based on the set fluctuation index exceeding a predetermined set threshold value.

[0046] The control device 50 of the gyratory crusher 100 according to the first item can also be expressed as follows: That is, the control device 50 includes a processor and a memory that stores a program executable by the processor and is accessible from the processor, and the processor that executes the program (i) generates a set target value that controls the crushing load to a predetermined crushing load target value, (ii) operates the hydraulic circuit 90 to control the set to the set target value, and (iii) calculates a set fluctuation index that indicates the degree of sudden increase in the set, and detects an abnormal increase in the crushing load based on the set fluctuation index exceeding a predetermined set threshold.

[0047] The control device 50 of the gyratory crusher 100 relating to the second item of the present disclosure is the control device 50 of the gyratory crusher 100 relating to the first item, in which the set fluctuation index is the difference d between the set detection value detected by the set sensor 52 and the moving average value of the set detection value.

[0048] The control device 50 of the crusher 100 relating to the third item of the present disclosure is the control device 50 of the gyratory crusher 100 relating to the first item, in which the set fluctuation index is the increase per unit time of the difference between the set detection value detected by the set sensor 52 and the set target value.

[0049] According to the control device 50 relating to the first to third items, a set sensor 52, which is a sensor provided in conventional crushers, can be used to detect a sudden increase in crushing load caused by, for example, the introduction of foreign matter into the crushing chamber 16. By being able to detect a sudden increase in crushing load in this way, measures to eliminate the overload can be taken in addition to operating the accumulator 92, and the overload can be quickly eliminated, thereby making it possible to avoid the tapping phenomenon.

[0050] The control device 50 for the crusher 100 according to the fourth aspect of the present disclosure is the control device 50 for the gyratory crusher 100 according to any one of the first to third aspects, wherein the load abnormality detection unit 85 detects an abnormal increase in the crushing load based on the fact that the set fluctuation index has exceeded a set threshold value and the cylinder oil pressure has exceeded a predetermined oil pressure threshold value.

[0051] According to the control device 50 of the crusher 100 having the above-described configuration, the cylinder oil pressure is also used as a determination factor in addition to the set fluctuation index, so that a sudden increase in the crushing load can be detected more accurately.

[0052] The control device 50 of the crusher 100 relating to the fifth item of the present disclosure is the control device 50 of the gyratory crusher 100 relating to any one of the first to fourth items, and further includes an overload elimination control unit 86 that temporarily generates a set target value in place of the load stabilization control unit 84 when an abnormal increase in crushing load is detected, and the overload elimination control unit 86 sets a predetermined set reference value that is smaller than the set detection value detected by the set sensor 52 as the set target value, and then generates a new set target value by adding a predetermined set addition value to the set target value, and repeats this process until the set target value becomes equal to or greater than the set detection value.

[0053] The control device 50 of the crusher 100 relating to the sixth item of the present disclosure is the control device 50 of the gyratory crusher 100 relating to any one of the first to fourth items, and further includes an overload elimination control unit 86 that temporarily generates a set target value in place of the load stabilization control unit 84 when an abnormal increase in crushing load is detected, and the overload elimination control unit 86 sets the maximum set detection value detected by the set sensor 52 after the abnormal increase is detected as the set target value, and then sets the larger of the current set target value and the set detection value from a predetermined time ago as the new set target value, and repeats this process until the set fluctuation index becomes equal to or less than the set threshold value.

[0054] According to the control device 50 of the crusher 100 relating to the fifth and sixth items, the control for stabilizing the crushing load is temporarily stopped, and processing for actively eliminating the overload is performed, thereby quickly eliminating the overload state.

[0055] The control device 50 of the crusher 100 relating to the seventh item of the present disclosure is a control device 50 of the gyratory crusher 100 relating to the fifth or sixth item, in which, after the overload elimination control unit 86 generates a set target value, the set fluctuation index falls below the set threshold and a predetermined off-delay time has elapsed, the load stabilization control unit 84 generates a set target value instead of the overload elimination control unit 86.

[0056] As a result, when the overload state is resolved, control for stabilizing the crushing load is automatically resumed.

[0057] The crusher 100 according to the eighth item of the present disclosure comprises a main shaft 5, a mantle 13 fixed to the main shaft 5, a concave 14 arranged to face the mantle 13 and forming a crushing chamber 16 between the mantle 13, a set sensor 52 that detects the set between the mantle 13 and the concave 14, a hydraulic cylinder 6 that supports the lower part of the main shaft 5, a hydraulic circuit 90 that has an accumulator 92 connected to the hydraulic chamber 63 of the hydraulic cylinder 6 and generates cylinder oil pressure that changes the set in the hydraulic chamber 63, crushing load detectors 55, 56 that detect the crushing load, and a control device 50 for a gyratory crusher 100 according to any one of the first to seventh items.

[0058] A control method for a crusher 100 according to a ninth aspect of the present disclosure is a control method for a gyratory crusher 100 including a main shaft 5, a mantle 13 fixed to the main shaft 5, a concave 14 arranged to face the mantle 13 and forming a crushing chamber 16 between the mantle 13, a set sensor 52 for detecting a set between the mantle 13 and the concave 14, a hydraulic cylinder 6 supporting the main shaft 5, a hydraulic circuit 90 having an accumulator 92 connected to a hydraulic chamber 63 of the hydraulic cylinder 6 and generating a cylinder oil pressure for changing the set in the hydraulic chamber 63, and a crushing load detector for detecting a crushing load, the control method comprising the steps of: acquiring a detected value of the crushing load, and generating a set target value for controlling the crushing load to a predetermined crushing load target value; operating the hydraulic circuit 90 to control the set to the set target value; acquiring the detected value of the set, determining a set fluctuation index representing the degree of sudden increase in the set, and detecting an abnormal increase in the crushing load based on the set fluctuation index exceeding a predetermined set threshold value.

[0059] According to the above-described control method for the crusher 100, a sudden increase in the crushing load caused by, for example, the introduction of a foreign object into the crushing chamber 16 can be detected using the set sensor 52, a sensor provided in conventional crushers. By being able to detect a sudden increase in the crushing load in this way, the accumulator 92 can be activated and measures to eliminate the overload can be taken to quickly eliminate the overload, thereby making it possible to avoid the tapping phenomenon.

[0060] The foregoing discussion of the present disclosure has been presented for purposes of illustration and description and is not intended to limit the present disclosure to the form disclosed herein. For example, in the foregoing detailed description, various features of the present disclosure are grouped together in a single embodiment for the purpose of streamlining the disclosure, but some of the features may also be combined. Furthermore, the features included in the present disclosure may be combined into alternative embodiments, configurations, or aspects other than those discussed above.

Claims

1. A control device for a gyratory crusher comprising: a main shaft; a mantle fixed to the main shaft; a concave arranged opposite the mantle and forming a crushing chamber between it and the mantle; a set sensor for detecting a set between the mantle and the concave; a hydraulic cylinder supporting the main shaft; a hydraulic circuit having an accumulator connected to the hydraulic chamber of the hydraulic cylinder and generating cylinder oil pressure in the hydraulic chamber to change the set; and a crushing load detector for detecting a crushing load, the control device comprising: a load stabilization control unit for generating a set target value that controls the crushing load to a predetermined crushing load target value; a set control unit for operating the hydraulic circuit to control the set to the set target value; and a load abnormality detection unit for calculating a set fluctuation index that indicates the degree of sudden increase in the set, and detecting an abnormal increase in the crushing load based on the set fluctuation index exceeding a predetermined set threshold.

2. The control device for a gyratory crusher according to claim 1, wherein the set fluctuation index is a difference between the set detection value detected by the set sensor and a moving average value of the set detection value.

3. The control device for a gyratory crusher according to claim 1, wherein the set fluctuation index is an increase per unit time of the difference between the set detection value detected by the set sensor and the set target value.

4. A control device for a gyratory crusher as described in any one of claims 1 to 3, wherein the load abnormality detection unit detects an abnormal increase in the crushing load based on the set fluctuation index exceeding the set threshold value and the cylinder oil pressure exceeding a predetermined oil pressure threshold value.

5. A control device for a gyratory crusher as described in claim 1, further comprising an overload elimination control unit that, when an abnormal increase in the crushing load is detected, temporarily generates the set target value in place of the load stabilization control unit, and the overload elimination control unit sets the set target value to a predetermined set reference value that is smaller than the set detection value detected by the set sensor, and then generates a new set target value by adding a predetermined set addition value to the set target value, repeating this process until the set target value becomes equal to or greater than the set detection value.

6. A control device for a gyratory crusher as described in claim 1, further comprising an overload elimination control unit that, when an abnormal increase in the crushing load is detected, temporarily generates the set target value in place of the load stabilization control unit, wherein the overload elimination control unit sets the maximum set detection value detected by the set sensor after the abnormal increase is detected as the set target value, and then sets the larger of the current set target value and the set detection value from a predetermined time ago as the new set target value, repeating this process until the set fluctuation index becomes equal to or less than the set threshold value.

7. A control device for a gyratory crusher as described in claim 5 or 6, wherein after the overload elimination control unit generates the set target value, the load stabilization control unit generates the set target value instead of the overload elimination control unit after the set fluctuation index becomes equal to or less than the set threshold and a predetermined off-delay time has elapsed.

8. A gyratory crusher comprising: a main shaft; a mantle fixed to the main shaft; a concave arranged opposite the mantle and forming a crushing chamber between it and the mantle; a set sensor detecting a set between the mantle and the concave; a hydraulic cylinder supporting a lower part of the main shaft; a hydraulic circuit having an accumulator connected to a hydraulic chamber of the hydraulic cylinder and generating cylinder hydraulic pressure in the hydraulic chamber to change the set; a crushing load detector detecting a crushing load; and a control device for a gyratory crusher according to any one of claims 1 to 3.

9. A control method for a gyratory crusher comprising: a main shaft; a mantle fixed to the main shaft; a concave arranged opposite the mantle and forming a crushing chamber between it and the mantle; a set sensor detecting a set between the mantle and the concave; a hydraulic cylinder supporting the main shaft; a hydraulic circuit having an accumulator connected to a hydraulic chamber of the hydraulic cylinder and generating cylinder oil pressure in the hydraulic chamber to change the set; and a crushing load detector detecting a crushing load, the control method comprising: acquiring a detected value of the crushing load, and generating a set target value for controlling the crushing load to a predetermined crushing load target value; operating the hydraulic circuit to control the set to the set target value; acquiring the detected value of the set, determining a set fluctuation index representing the degree of sudden increase in the set, and detecting an abnormal increase in the crushing load based on the set fluctuation index exceeding a predetermined set threshold.

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