JP7116842B2 - GYRTING CRUSHER AND OVERLOAD DETECTION DEVICE AND METHOD THEREOF - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for detecting that the crusher is being operated in an overloaded state in a gyration crusher used for crushing rocks, ores, and the like.

BACKGROUND ART Conventionally, there has been known a gyration crusher in which a truncated cone-shaped mantle placed inside a conical cylindrical cone cave is eccentrically rotated to crush ore by biting it between the cone cave and the mantle. . The gap between the two crushing surfaces of the cone and mantle varies periodically, and the size of the opening (set) at the narrowest point of the gap determines the grain size of the grind. The gyration crusher is classified into a hydraulic type and a mechanical type according to the method of changing the set.

Patent Literature 1 discloses a mechanical orbital crusher. This rotary crusher includes a lower frame supporting a main shaft to which a mantle is fixed, an upper frame supporting a cone cave, and an elevating device for elevating the cone head with respect to the mantle. In this mechanical orbital crusher, the set is changed by raising and lowering the cone head with respect to the mantle with a lifting device. The mechanical orbital crusher further comprises a plurality of frame cylinders (hydraulic cylinders) circumferentially distributed around the cone head. The set is held at a predetermined value by the hydraulic force exerted on the cone cavity against the crushing force by the frame cylinder.

Patent Literature 2 discloses a hydraulic orbital crusher. This gyration crusher includes a lower frame that supports a main shaft to which a mantle is fixed, an upper frame that supports a cone cave, a drive motor that drives the mantle to gyrate, and a main shaft thrust bearing that supports the main shaft. The main shaft thrust bearing includes a ram that is raised and lowered by a hydraulic cylinder, and displacement of the ram raises and lowers the mantle relative to the cone cave to change the set. In the hydraulic orbital crusher, the set is held at a predetermined value by applying hydraulic pressure to the mantle against the crushing force by the hydraulic pressure of the hydraulic cylinder.

In the mechanical and hydraulic gyration crushers as described above, the crushing force acting on the mantle and cone cave may exceed the hydraulic force, resulting in tapping. Tapping can represent or be a precursor to an abnormal overload condition in the operation of the crusher. One cause of tapping is packing that occurs in the crushing chamber between the mantle and the cone cave. Packing refers to the state in which the crushing chamber is filled with raw stones without any gaps or is compressed and overcrowded. There are various reasons for packing, such as narrow sets, many fine particles adhering to the ore, and the ore containing a lot of moisture. If the crusher continues to operate in an abnormally overloaded state, the crushing capacity will be significantly reduced, and there is a risk of damage to the elements of the crusher.

Therefore, in Patent Document 1, by detecting the line pressure of lubricating oil in the spherical thrust bearing that supports the cone head and comparing the detected pressure with a set value, it is possible to detect that the crusher is being operated in an overloaded state. to detect

JP-A-6-182240 JP-A-53-137467

In Patent Document 1, the lubricating oil line pressure of the spherical thrust bearing is detected. changes. As described above, in the orbital crushing, since the crushing force constantly fluctuates, the line pressure of the lubricating oil constantly fluctuates. Similarly, in a hydraulic orbital crusher, the hydraulic pressure value of the hydraulic cylinder of the main bearing constantly fluctuates. In the mechanical orbital crusher, the hydraulic pressure (frame pressure) of the frame cylinder is a predetermined pressure for clamping the upper frame and the lower frame. However, the flame pressure gradually decreases due to an internal leak or the like. Therefore, when the flame pressure drops below a predetermined level, repressurization is performed to keep the flame pressure within a certain range. In this way, the flame pressure constantly fluctuates greatly, and when using the constantly fluctuating measured value to detect an overload state, it is not easy to extract an abnormal element from the measured value without error. do not have.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a gyration-type crusher in which the crusher is operated in an overloaded state while using measured values that fluctuate steadily. It is to detect that with high precision.

An overload detection device for a gyration-type crusher according to one aspect of the present invention includes a mantle fixed to a main shaft that performs an eccentric gyration motion, and a cone cavity that forms a crushing chamber between the mantle and the mantle for biting and crushing raw stones. and a hydraulic cylinder that applies hydraulic pressure to the mantle or cone to hold a predetermined set of the mantle and cone to oppose the crushing force and is operated in an overload condition. A device for detecting the presence of
a hydraulic sensor that detects the hydraulic pressure of the hydraulic cylinder;
a storage device that acquires information about the hydraulic pressure from the hydraulic sensor and stores the information in association with a sampling time;
When a plurality of consecutive sampling intervals are defined as a detection period, the time during which the hydraulic pressure exceeds a predetermined pressure threshold is accumulated, and the ratio of the accumulated time to the detection period exceeds the predetermined ratio threshold and a computing device for detecting that the crusher is being operated in an overloaded state.

In addition, the gyration type crusher according to one aspect of the present invention is
mantle and
a main shaft on which the mantle is fixed and eccentrically rotated;
a lower frame supporting the main shaft;
a cone cavity forming a crushing chamber between the mantle and the mantle, in which the ore is bitten and crushed;
an upper frame supporting the cone cave;
a hydraulic cylinder that provides hydraulic force against crushing forces to the mantle or cone to hold a predetermined set of the mantle and cone;
and the overload detection device.

Further, in the method for detecting overload of a rotary crusher according to one aspect of the present invention, a mantle fixed to a main shaft that performs an eccentric rotary motion and a crushing chamber that bites and crushes ores are formed between the mantle and the mantle. and hydraulic cylinders that apply hydraulic pressure to the mantle or cone cavities to oppose the crushing force so as to retain a predetermined set of the mantle and the cone caves is operated in an overload condition. A method for detecting that
detecting the hydraulic pressure of the hydraulic cylinder and storing the hydraulic pressure in association with a sampling time;
A plurality of consecutive sampling times are defined as a detection period, the time during which the hydraulic pressure exceeds a predetermined pressure threshold is accumulated, and the ratio of the accumulated time to the detection period exceeds the predetermined ratio threshold. and detecting that the crusher is operating in an overload condition.

According to the orbital crusher and its overload detection device and method, the detection period is set, and the load state of the crusher is detected at the ratio of the time during which the hydraulic pressure is higher than the pressure threshold during the detection period. presume. By setting the detection period in this manner, the influence of short-term fluctuations in hydraulic pressure is suppressed. As a result, erroneous detection of an overload state can be suppressed. Therefore, according to the present invention, it is possible to detect with high accuracy that the crusher is being operated in an overloaded state while using the measured value of the hydraulic pressure that fluctuates steadily.

According to the present invention, it is possible to detect with high accuracy that the crusher is being operated in an overloaded state, while using measured values that constantly fluctuate.

FIG. 1 is a diagram showing a schematic configuration of a gyration-type crusher equipped with an overload detection device according to a first embodiment of the present invention. FIG. 2 is a diagram showing the configuration of the hydraulic system of the overload detection device and the frame cylinder according to the first embodiment. FIG. 3 is a graph showing time series changes in flame pressure during normal operation. FIG. 4 is a flow chart of overload detection processing by the overload detection device. FIG. 5 is a graph showing time series changes in flame pressure during overload operation. FIG. 6 is a diagram for explaining the detection period. FIG. 7 is a diagram showing a schematic configuration of a rotary crusher equipped with an overload detection device according to a second embodiment of the present invention. FIG. 8 is a diagram showing the configuration of an overload detection device and a hydraulic system of bearing cylinders according to the second embodiment.

[First embodiment]
Next, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing a schematic configuration of a gyration-type crusher 10 equipped with an overload detection device 9 according to a first embodiment of the present invention. The gyration crusher 10 according to this embodiment is a mechanical gyration crusher 10 .

[Schematic configuration of gyration crusher 10]
The gyration-type crusher 10 shown in FIG.

The cone cave support assembly 1 is formed by integrally joining an input hopper 11 and a cone cave 12 with a cone cave support 14 interposed therebetween. A gear plate 13 is fixed to the cone support 14 . Further, an external thread is formed on the outer periphery of the cone cave support 14 .

The frame assembly 2 has an upper frame 21 and a lower frame 22 . The upper frame 21 supports the cone cave support assembly 1 so as to be vertically movable. The lower frame 22 forms a duct for guiding out the crushed stone product and houses the eccentric sleeve assembly 6 . The upper frame 21 and the lower frame 22 are fixed by being vertically sandwiched between the frame cylinders 4 . More specifically, the frame cylinder 4 is a hydraulic cylinder composed of a cylinder and a cylinder rod. The cylinder of the frame cylinder 4 is attached to the lower frame 22 and the cylinder rod of the frame cylinder 4 is locked to the upper frame 21. . The upper frame 21 is prevented from rising by the hydraulic force that holds the position of the cylinder rod.

The upper frame 21 is formed with internal threads that engage with the external threads of the cone cave support 14 . A set adjustment base 23 is fixed to the upper frame 21 . The set adjustment frame 23 is provided with a gear 24 that meshes with the gear of the gear plate 13 and a motor 27 that drives the gear 24 to rotate.

Eccentric sleeve assembly 6 includes transverse shaft 62 and eccentric sleeve 65 . The horizontal shaft 62 is supported by the lower frame 22 via bearings. A V-pulley 61 is fixed to one end of the horizontal shaft 62, and a bevel pinion 63 is fixed to the other end. The eccentric sleeve 65 is rotatably fitted in a vertical hole provided in the lower frame 22 and rotates around a vertical axis of rotation. The eccentric sleeve 65 is provided with a vertical hole at an eccentric position where the central axis intersects at one point (apex 66) on the rotation axis, and the main shaft 31 is inserted into this vertical hole. A bevel gear 64 meshing with the bevel pinion 63 is fixed to the eccentric sleeve 65 .

Rotational power from the electric motor 18 is transmitted to the horizontal shaft 62 via the V-belt and V-pulley 61 and further transmitted to the eccentric sleeve 65 via the bevel pinion 63 and the bevel gear 64 . As a result, the main shaft 31 performs a grinding motion (so-called precession motion) such that the axis passes through the upper vertex 66 . Such a grinding motion of the main shaft 31 is called a turning motion here.

The spindle assembly 3 includes a spindle 31 , a mantle core 33 and a mantle 34 . The mantle core 33 is fixed to the main shaft 31 . A peripheral groove into which a dust ring 25 fixed to the lower frame 22 is inserted is formed in the lower end of the mantle core 33 . A mantle 34 is fixed to the outer circumference of the mantle core 33 . The mantle 34 is funnel-shaped with a hole at the top and is made of a highly wear-resistant material such as, for example, high manganese cast steel.

A crushing chamber 47 is formed between the cone cave 12 and the mantle 34 and has a cross-sectional shape whose diameter increases downward. The thickness of the space of the crushing chamber 47 becomes thinner toward the bottom from the input hopper 11, and becomes narrower at the lowermost circumferential opening.

The distance (set) between the mantle 34 and the cone cave 12 in the crushing chamber 47 is adjusted according to the properties of the raw stone 67 to be crushed and the grain size of the product crushed stone 68 . When the cone support 14 is rotated by driving the gear 24 of the set adjustment frame 23, the screwing depth of the cone support 14 with respect to the upper frame 21 changes. This changes the distance between the mantle 34 and the cone 12 to adjust the set. The size of the set is measured by an ultrasonic set sensor 26 provided on the upper frame 21 .

In the orbital crusher 10 having the above configuration, the distance between the cone cable 12 and the mantle 34 in the crushing chamber 47 repeats widening and narrowing due to the eccentric orbital motion of the main shaft 31 . The ore 67 pushed down from the input hopper 11 to the crushing chamber 47 is crushed between the cone cave 12 and the mantle 34 . The raw stone 67 in the crushing chamber 47 is repeatedly crushed and dropped, and gradually becomes finer as it falls. The raw stone 67 that has been reduced to a predetermined size is discharged from the lower frame 22 through the lower end opening of the crushing chamber 47 as product crushed stone 68 having a predetermined particle size.

[Overload detection device 9 of gyration crusher 10]
During the operation of the orbital crusher 10, the crushing load fluctuates due to disturbances such as the properties and moisture content of the raw stone 67, changes in the level of the raw stone 67 in the input hopper 11, and the inclusion of foreign substances such as metal pieces. . Here, the "crushing load" means a load applied to the electric motor 18 due to crushing. When the output shaft of the electric motor 18 is overloaded to a predetermined value or more, the rotation of the output shaft is locked and the overload protection circuit is activated to bring the motor to an emergency stop. Therefore, the orbital crusher 10 according to this embodiment includes an overload detector 9 that monitors the hydraulic pressure of the frame cylinder 4 and detects an excessive crushing load based on the change in the hydraulic pressure.

As shown in FIG. 2, a hydraulic circuit 70 is connected to the frame cylinder 4 . The hydraulic circuit 70 supplies hydraulic fluid to a first hydraulic chamber 4a on the piston retracting side of the frame cylinder 4 and to a second hydraulic chamber 4b on the piston advancing side of the frame cylinder 4. a second oil passage 73; an oil supply passage 75 for selectively supplying oil from the oil tank 71 to one of the first oil passage 72 and the second oil passage 73; and an oil drain passage 74 for discharging hydraulic oil to the tank 71 . A gear pump 76 that pumps hydraulic oil is provided in the oil supply path 75 . A gear pump 76 is rotationally driven by a pump motor 77 . A switching valve for switching between a state of being connected to the first oil passage 72, a state of being connected to the second oil passage 73, and a state of not being connected to the first oil passage 72 and the second oil passage 73. 78 is provided. An accumulator 42 is connected to the first oil passage 72 communicating with the first hydraulic chamber 4a. However, the configuration of the hydraulic circuit 70 is not limited to the above.

The hydraulic circuit 70 configured as described above is controlled by the cylinder control device 44 . The cylinder control device 44 is electrically connected to the pump motor 77 and the switching valve 78, and outputs control signals to these devices. The cylinder control device 44 is also electrically connected to the set sensor 26 and the hydraulic pressure sensor 41 and acquires hydraulic pressure information detected by the hydraulic pressure sensor 41 .

As the hydraulic fluid flows into the first hydraulic chamber 4a, the hydraulic pressure of the frame cylinder 4 (hereinafter referred to as "frame pressure") increases. When the crushing chamber 47 is contaminated with foreign matter that cannot be crushed, the amount of raw stones 67 charged is temporarily increased, or the crusher 10 is overloaded, the cone 12 is pushed up. As a result, the flame pressure rises, and hydraulic oil flows into the accumulator 42 so as to absorb it. When the overload condition is removed, the hydraulic oil in the accumulator 42 flows to the frame cylinder 4 and returns to the original crushing gap so that normal operation can be resumed.

FIG. 3 is a graph showing time-series changes in flame pressure during normal operation, in which the vertical axis represents flame pressure and the horizontal axis represents time. As shown in this graph, the flame pressure gradually decreases over time due to internal leakage of hydraulic fluid and the like. Although the graph looks linear, if enlarged, the flame pressure fluctuates finely up and down even during steady operation. In the flame cylinder 4, repressurization (that is, forced pressurization) is automatically performed in order to keep the flame pressure within a predetermined range. Repressurization is the process of intentionally forcing the flame pressure to rise. Repressurization is, for example, sending a predetermined amount of hydraulic fluid to the frame cylinder 4, sending hydraulic fluid to the frame cylinder 4 for a predetermined period of time, and sending hydraulic fluid to the frame cylinder 4 until the flame pressure recovers a predetermined amount. may be any one of

The cylinder control device 44 performs repressurization at a predetermined timing. The timing of repressurization is, for example, any one of when a predetermined time has passed since the previous repressurization, when the frame pressure falls below a predetermined threshold value, and when a pre-scheduled time arrives. can be Cylinder controller 44 controls hydraulic circuit 70 to deliver hydraulic fluid to frame cylinder 4 upon repressurization. Such repressurization causes the flame pressure to rise sharply.

As described above, the flame pressure has one cycle of a gentle drop and a sudden rise due to repressurization, and this cycle is repeated. Flame pressure is constantly changing and is not fixed at a constant value. The overload detection device 9 detects an overload by extracting the pressure fluctuation due to the overload from the measured value of the frame pressure fluctuating in this way by a predetermined logic.

The overload detection device 9 may be embodied as a kind of computer such as a PLC (programmable controller). The overload detection device 9 includes an arithmetic device 9a and a volatile and nonvolatile storage device 9b. The computing device 9a is composed of a CPU, an MPU, a GPU, etc., and performs overload detection processing by reading and executing various programs stored in the storage device 9b. The overload detection device 9 is electrically connected to the cylinder control device 44 . The overload detection device 9 acquires the repressurization timing from the cylinder control device 44 . The overload detection device 9 is electrically connected to the oil pressure sensor 41 and acquires oil pressure information (frame pressure) detected from the oil pressure sensor 41 .

FIG. 4 is a flow chart of overload detection processing by the overload detection device 9 . FIG. 5 is a graph showing time-series changes in frame pressure during overload. Note that the scale of FIG. 5 is different from that of the graph of FIG. 3, and is sufficiently enlarged so that fluctuations in the flame pressure can be read.

The overload detection device 9 acquires the hydraulic pressure (that is, the frame pressure P) which is the detection value of the hydraulic pressure sensor 41 during operation of the rotary crusher 10, associates the frame pressure P with the sampling time, and stores it in the storage device. 9b sequentially. Based on the signal sent from the cylinder control device 44, the overload detection device 9 stores the timing of repressurization of the frame cylinder 4 in the storage device 9b.

The overload detection device 9 detects an overload state based on the time-series data of the frame pressure P accumulated as described above and the obtained frame pressure P. FIG. As shown in FIG. 4, the overload detector 9 determines whether the flame cylinder 4 is being repressurized (step S1). The overload detection device 9 can determine whether or not the frame cylinder 4 is being repressurized based on the signal sent from the cylinder control device 44 . If the overload detection device 9 is not repressurizing (NO in step S1), it initializes the detection period timer (t1=0) and the integration timer (t2=0) (step S2). Then, the overload detection device 9 starts counting the detection time t1 with the detection period timer (step S3). As shown in FIG. 6, the detection period T1 includes M successive sampling intervals S. As shown in FIG. The number of sections M is an arbitrary natural number (plurality) and is stored in advance in the overload detection device 9 . The time of one sampling interval S is the detection cycle of the oil pressure sensor 41 .

The overload detection device 9 acquires the frame pressure Pn, which is the detection value of the hydraulic sensor 41, in the current sampling interval _Sn , and compares it with the pressure threshold α (step S4).

The pressure threshold α can be obtained from the time-series data of the frame pressure P accumulated. The pressure threshold α may be the moving average Pm of the frame pressure P multiplied by a coefficient C. The coefficient C is a real number of 1 or more. The coefficient C is predetermined and stored in the overload detection device 9 . The moving average Pm is the arithmetic average of the frame pressures P _n-N+1 to P _n-1 in N consecutive sampling intervals S _n-N+1 to S _n-1 . The number of sections N is an arbitrary natural number and is pre-stored in the overload detection device 9 . Although N shown in FIG. 6 is smaller than M, N may be larger than M. The N sampling intervals S _n−N+1 to S _n−1 include the sampling interval S _n−1 immediately preceding the current sampling interval S _n .

If the flame pressure P is greater than the pressure threshold value α (YES in step S4), the overload detection device 9 sets the time of the interval (the time during which the frame pressure P is greater than the pressure threshold value α) to an accumulation timer. is counted (step S5). If the flame pressure P is equal to or less than the pressure threshold value α (NO in step S4), the overload detection device 9 does not count the time in that section with the integration timer.

The overload detection device 9 repeats the above steps S4 to S5 until the detection time t1 counted by the detection period timer reaches or exceeds the predetermined detection period T1 (step S6). As a result, an integrated value T2 of the time during which the frame pressure P is greater than the pressure threshold α is obtained in the detection period T1.

The overload detection device 9 obtains the ratio R of the integrated value T2 during which the frame pressure P is greater than the pressure threshold value α for the detection period T1 (step S7), and compares it with a predetermined ratio threshold value β (step S8 ). The ratio threshold value β is determined in advance by simulation, experiment, or the like, and stored in the overload detection device 9 . When the ratio R of the integrated value T2 to the detection period T1 is greater than the ratio threshold value β (YES in step S8), the overload detection device 9 determines that an overload is detected (step S9), and detects a predetermined overload. Post-processing is performed (step S10), and the overload detection process ends. Overload detection post-processing includes outputting a stop command to a raw stone feeder (not shown), overload detection display output to a monitor (not shown), overload detection display output to an alarm device (not shown), and overload detection to the cylinder control device 44. output of a signal. When the ratio R of the integrated value T2 to the detection period T1 is equal to or less than the ratio threshold value β (NO in step S8), the overload detection device 9 determines that there is no overload and terminates the overload detection process. The overload detection device 9 may repeat the series of overload detection processes described above while the gyration crusher 10 is in operation.

As described above, the orbital crusher 10 of this embodiment includes the mantle 34, the main shaft 31 to which the mantle 34 is fixed and which performs eccentric orbital motion, the lower frame 22 that supports the main shaft 31, and the mantle 34. The cones 12 forming a crushing chamber 47 that bites and crushes the rough 67 between them, an upper frame 21 that supports the cones 12, and a crushing force on the cones 12 to hold a predetermined set of mantles 34 and cones 12. and a frame cylinder 4 (corresponding to a “hydraulic cylinder” in the claims) for applying a hydraulic force opposing to , and an overload detection device 9 . The overload detection device 9 has a hydraulic sensor 41 that detects the hydraulic pressure of the frame cylinder 4, a storage device 9b, and an arithmetic device 9a. The storage device 9b acquires information about the hydraulic pressure from the hydraulic sensor 41 and stores it in association with the sampling time. The calculation device 9a sets a plurality of continuous sampling intervals as a detection period T1, obtains a pressure threshold α using a moving average of the hydraulic pressure (frame pressure in this embodiment), and determines that the hydraulic pressure is within the detection period T1. When the time exceeding α is accumulated, and the ratio of the accumulated time T2 to the detection period T1 (T2/T1) exceeds a predetermined ratio threshold value β, the tumbling crusher 10 is being operated in an overloaded state. detect that there is

Further, the overload detection method for the gyration crusher 10 according to the present embodiment detects the frame pressure, which is the hydraulic pressure of the frame cylinder 4 (corresponding to the "hydraulic cylinder" in the claims), and detects the frame pressure. Storing in association with the sampling time, setting a plurality of continuous sampling times as a detection period T1, integrating the time during which the frame pressure exceeds a predetermined pressure threshold α within the detection period T1, and adding the integrated time T2 detecting that the tumbling crusher 10 is operating in an overload condition when the ratio of T2/T1 to the detection period T1 exceeds a predetermined ratio threshold β.

According to the overload detection device 9 and method for the orbital crusher 10 according to the present embodiment, the detection period T1 is set, and the frame pressure in the detection period T1 is higher than the pressure threshold value α at the rate of the time T2. , to estimate the load state of the tumbling crusher 10 . By setting the detection period T1 in this manner, the influence of short-term fluctuations in the frame pressure is suppressed. As a result, erroneous detection of an overload state can be suppressed. Therefore, it is possible to detect with high accuracy that the crusher 10 is being operated in an overloaded state while using the measured values of the flame pressure that fluctuate steadily.

Further, in the overload detection device 9 and method for the gyration-type crusher 10 according to the present embodiment, the pressure threshold value α for the hydraulic pressure in the current _sampling section _{Sn is} It is a value obtained by multiplying the moving average Pm including the detection value of _-1 by a coefficient C of 1 or more.

Thus, the pressure threshold α can be appropriately set with respect to the hydraulic pressure of the frame cylinder 4, which constantly fluctuates.

In addition, in the overload detection device 9 and the method for the orbital crusher 10 according to the present embodiment, the detection period T1 does not include the period of repressurization by the frame cylinder 4 .

As a result, periodic and large fluctuations are removed from the detected value during the detection period T1. Therefore, the value of the pressure threshold α is appropriately set. Also, the overload state of the gyration crusher 10 can be detected with higher accuracy.

[Second embodiment]
Next, a second embodiment of the invention will be described. FIG. 7 is a diagram showing a schematic configuration of a rotary crusher 110 having an overload detector 109 according to a second embodiment of the present invention. The gyration crusher 110 according to this embodiment is a hydraulic gyration crusher 110 . In the description of this embodiment, the same or similar members as those of the above-described embodiment are denoted by the same reference numerals in the drawings, and descriptions thereof are omitted.

In the conventional hydraulic orbital crusher, when foreign matter that cannot be crushed or excessive raw materials are fed, the crushing force acting on the mantle and cone cave exceeds the hydraulic force that opposes the crushing force, causing tapping. may occur. If the operation is continued while tapping occurs, the crusher body may be damaged or the raw material may overflow. Therefore, when tapping occurs, the operation must be temporarily stopped to remove the raw material from the crushing chamber, resulting in a significant drop in productivity. Also, when tapping occurs, the load rises sharply, so the thermal relay of the drive motor of the crusher cannot detect the abnormality. Therefore, the current value of the drive motor and the holding pressure of the spindle, which corresponds to the crushing pressure, are measured, and if the measured value exceeds a predetermined threshold value for a predetermined period of time, an abnormality is detected. there is However, the hydraulic gyration crusher suffers from short-cycle load fluctuations caused by gyration crushing, and load fluctuations caused by changes in raw material properties, raw material size, and raw material moisture content. It was difficult to reliably detect an overload anomaly with such a conventional anomaly detection method. Therefore, a method for detecting an overload state with higher accuracy in the hydraulic gyration crusher 110 as well as in the mechanical gyration crusher 10 according to the first embodiment will be described below.

[Schematic configuration of gyration crusher 110]
As shown in FIG. 7, the rotary crusher 110 includes a hopper 11 that stores crushed objects, a mantle 34 and cone caves 12 that catch and crush the crushed objects that have fallen from the hopper 11, and the mantle 34 that rotates. It is provided with an electric motor 18 as driving means, a power transmission mechanism 19 for transmitting rotational power from the electric motor 18 to the mantle 34 , and a bearing cylinder 8 (hydraulic cylinder) for raising and lowering the mantle 34 with respect to the cone cave 12 .

The gyration crusher 110 further comprises a frame assembly 2 consisting of an upper frame 21 and a lower frame 22 . The upper frame 21 and the lower frame 22 are fixed while facing each other vertically. A conical tubular cone 12 is provided on the inner circumference of the upper frame 21 . A truncated cone-shaped mantle 34 is arranged inside the cone cave 12 . Between the crushing surfaces of the cone cave 12 and the crushing surface of the mantle 34 facing each other with a gap therebetween, a crushing chamber 47 having a cross-sectional shape whose diameter increases downward is formed. The thickness of the space of the crushing chamber 47 becomes thinner toward the bottom from the input hopper 11, and becomes narrower at the lowermost circumferential opening. The distance (set) between the mantle 34 and the cone cave 12 in the crushing chamber 47 is adjusted according to the properties of the raw stone 67 to be crushed and the grain size of the product crushed stone 68 . A set adjuster 80 raises and lowers the mantle 34 with respect to the cone cave 12 .

A mantle 34 is attached to a mantle core 33 fixed to the top of the main shaft 31 . A mantle 34 is fixed to the outer circumference of the mantle core 33 . A peripheral groove into which a dust ring 25 fixed to the lower frame 22 is inserted is formed in the lower end of the mantle core 33 . The main shaft 31 is arranged in the frame assembly 2 with its axis tilted from the vertical direction. The upper end of the main shaft 31 is rotatably supported by an upper bearing 35 provided at the upper end of the upper frame 21 . A lower portion of the main shaft 31 is fitted in an inner bush 51 . The inner bushing 51 is fixed to the eccentric sleeve 65 . The eccentric sleeve 65 is fitted in the outer bushing 53 provided on the lower frame 22 . A lower end of the main shaft 31 is supported by a plain bearing 82 provided on a ram 81 of the bearing cylinder 8 .

The electric motor 18 is arranged outside the frame assembly 2 . The power transmission mechanism 19 transmits power from the electric motor 18 to the main shaft 31 to which the mantle 34 is fixed. Rotational power from the electric motor 18 is transmitted to the horizontal shaft 62 via the V-belt and V-pulley 61 and further transmitted to the eccentric sleeve 65 via the bevel pinion 63 and the bevel gear 64 . When the eccentric sleeve 65 rotates in response to the output of the electric motor 18, the main shaft 31 inserted into the eccentric sleeve 65 rotates eccentrically. As a result, the mantle 34 performs an eccentric turning motion, a so-called precession motion, with respect to the cone cave 12 whose position is fixed. The set (opening) of the crushing surface of the mantle 34 and the crushing surface of the cone cave 12 changes according to the turning position of the main shaft 31 .

The orbital crusher 110 according to this embodiment includes a bearing cylinder 8 as a set adjusting device 80 . The bearing cylinder 8 is a hydraulic cylinder composed of a cylinder tube 83 and a ram 81 that slides inside the cylinder tube 83 . The ram 81 supports a main shaft thrust bearing 82, and the main shaft thrust bearing 82 moves up and down as the ram 81 moves up and down. As the main shaft thrust bearing 82 moves up and down, the mantle 34 moves up and down with respect to the cone cave 12 to change the set (closed set) at the narrowest position of the gap between the two crushing surfaces of the cone cave 12 and the mantle 34 . A set sensor 126 (see FIG. 8) is provided to detect displacement of the ram 81 or the main shaft thrust bearing 82 . The position of the mantle 34 in the height direction with respect to the cone cave 12 is obtained from the position of the ram 81 detected by the set sensor 126 , and the set is obtained from the relative positional relationship between the cone cave 12 and the mantle 34 .

FIG. 8 is a diagram showing the configuration of the hydraulic system of the overload detection device 109 and the bearing cylinder 8 according to the second embodiment. As shown in FIGS. 7 and 8, a hydraulic chamber 85 is formed in the cylinder tube 83 of the bearing cylinder 8, the capacity of which changes according to the displacement of the ram 81. The hydraulic circuit 90 is connected to the hydraulic chamber 85. ing. The hydraulic oil in the oil tank 71 is supplied to the hydraulic chamber 85 through the hydraulic circuit 90, so that the ram 81 is lifted. Further, the ram 81 is lowered by draining the hydraulic oil in the hydraulic chamber 85 to the oil tank 71 through the hydraulic circuit 90 .

The hydraulic circuit 90 includes a communicating pipe 91 communicating with the lower portion of the hydraulic chamber 85, an accumulator 92 (or a balance cylinder) provided in the communicating pipe 91, an oil supply pipe 93 connected to the communication pipe 91, and an oil supply pipe 93. and an oil drain pipe 94 connected to the A hydraulic sensor 86 that detects the pressure of hydraulic fluid in the hydraulic chamber 85 is provided in the communication pipe 91 . The oil supply pipe 93 is provided with a gear pump 76 that pressure-feeds the hydraulic oil in the oil tank 71 to the hydraulic chamber 85 . A gear pump 76 is driven by a pump motor 77 . The oil supply pipe 93 is provided with a normally closed on-off valve 98 . The drain pipe 94 is provided with a normally closed on-off valve 99 . However, the configuration of the hydraulic circuit 90 is not limited to this embodiment.

The hydraulic circuit 90 configured as described above is controlled by a cylinder control device 144 . The cylinder control device 144 is electrically connected to the pump motor 77, the on-off valve 98, and the on-off valve 99, and outputs control signals to these devices. The cylinder control device 144 is also electrically connected to the set sensor 126 and acquires information detected by the set sensor 126 . The cylinder control device 144 operates the pump motor 77, the on-off valve 98, and the on-off valve 99 so that the set detected by the set sensor 126 becomes a predetermined value.

The hydraulic pressure of the bearing cylinder 8 fluctuates according to the turning motion of the main shaft 31 (mantle 34). Also, if the crushing chamber 47 is contaminated with foreign matter that cannot be crushed, if the amount of raw stones 67 charged temporarily increases, or if the crusher 110 becomes overloaded due to packing, the mantle 34 is pushed down. As a result, the hydraulic pressure in the bearing cylinder 8 rises, and hydraulic oil flows into the accumulator 92 so as to absorb it. When the overload condition is removed, the hydraulic oil in the accumulator 92 can flow to the bearing cylinder 8 and return to the original crush gap to resume normal operation. In this way, the hydraulic pressure in the bearing cylinder 8 constantly changes and does not settle at a constant value. The overload detection device 109 according to the present embodiment detects an overload by extracting the pressure fluctuation due to the overload from the measured value of the hydraulic pressure of the bearing cylinder 8 that fluctuates in this way by a predetermined logic.

The overload detection device 109 may be embodied as a kind of computer such as a PLC (programmable controller). The overload detection device 109 includes an arithmetic device 109a and a volatile and nonvolatile storage device 109b. The computing device 109a is composed of a CPU, an MPU, a GPU, etc., and performs overload detection processing by reading and executing various programs stored in the storage device 109b. The overload detection device 109 is electrically connected to the oil pressure sensor 86 and acquires oil pressure information detected from the oil pressure sensor 86 .

Here, the flow of load detection processing by the overload detection device 109 will be described. The processing flow of the overload detection device 109 according to the present embodiment is substantially the same as the processing of the overload detection device 9 according to the first embodiment except for step S1. can be explained by replacing "hydraulic force" with "hydraulic force".

Referring to FIG. 4, the overload detection device 109 acquires the hydraulic pressure detected by the hydraulic sensor 86 (that is, the hydraulic pressure of the bearing cylinder 8) while the orbiting crusher 110 is in operation. The pressure is sequentially stored in the storage device 109b in association with the sampling time. The overload detection device 109 detects an overload state based on the hydraulic pressure time-series data accumulated as described above and the obtained hydraulic pressure. The overload detection device 109 initializes the detection period timer (t1=0) and the integration timer (t2=0) (step S2). Then, the overload detection device 109 starts counting the detection time t1 with the detection period timer (step S3).

The overload detection device 109 acquires the hydraulic pressure Pn, which is the detection value (instantaneous value) of the hydraulic pressure sensor 86, in the current sampling interval _Sn , and compares it with the pressure threshold α (step S4). If the hydraulic pressure P is greater than the pressure threshold value α (YES in step S4), the overload detection device 109 sets the time of that section (the time during which the hydraulic pressure P is greater than the pressure threshold value α) to an integration timer. is counted (step S5). If the hydraulic pressure P is equal to or less than the pressure threshold value α (NO in step S4), the overload detection device 109 does not count the time of the section with the integration timer.

The overload detection device 109 repeats the above steps S4 to S5 until the detection time t1 counted by the detection period timer reaches or exceeds the predetermined detection period T1 (step S6). As a result, an integrated value T2 of the time during which the hydraulic pressure P is greater than the pressure threshold value α is obtained in the detection period T1.

The overload detection device 109 obtains the ratio R of the integrated value T2 during which the hydraulic pressure P is greater than the pressure threshold value α for the detection period T1 (step S7), and compares it with a predetermined ratio threshold value β (step S8 ). When the ratio R of the integrated value T2 to the detection period T1 is greater than the ratio threshold value β (YES in step S8), the overload detection device 109 determines that an overload is detected (step S9), and detects a predetermined overload. Post-processing is performed (step S10), and the overload detection process ends. When the ratio R of the integrated value T2 to the detection period T1 is equal to or less than the ratio threshold value β (NO in step S8), the overload detection device 109 ends the overload detection processing assuming that there is no overload. The overload detection device 109 may repeat the above series of overload detection processes while the orbital crusher 110 is in operation.

As described above, the orbital crusher 110 of this embodiment includes the mantle 34, the main shaft 31 to which the mantle 34 is fixed and which performs eccentric orbital motion, the lower frame 22 that supports the main shaft 31, and the mantle 34. The cones 12 forming a crushing chamber 47 that bites and crushes the rough stones 67 between them, the upper frame 21 that supports the cones 12, the mantle 34 and the crushing force on the mantle 34 to hold a predetermined set of cones 12. and an overload detection device 109. The overload detection device 109 has a hydraulic sensor 86 that detects the hydraulic pressure of the bearing cylinder 8, a storage device 109b, and an arithmetic device 109a. The storage device 109b acquires information about the hydraulic pressure P from the hydraulic sensor 86 and stores it in association with the sampling time. Arithmetic device 109a sets a plurality of continuous sampling intervals as detection period T1, integrates the time during which the hydraulic pressure exceeds pressure threshold α within the detection period T1, and calculates the ratio of integrated time T2 to detection period T1 (T2 /T1) exceeds a predetermined percentage threshold β, detecting that the orbital crusher 110 is operating in an overload condition.

Further, the overload detection method for the orbital crusher 110 according to the present embodiment detects the hydraulic pressure P of the bearing cylinder 8 (corresponding to the "hydraulic cylinder" in the claims), and detects the hydraulic pressure P at the sampling time. and storing a plurality of continuous sampling times as a detection period T1, integrating the time during which the hydraulic pressure P exceeds a predetermined pressure threshold α within the detection period T1, and calculating the integrated time T2 detecting that the tumbling crusher 110 is operating in an overload condition when the ratio of the detection period T1 (T2/T1) exceeds a predetermined ratio threshold β.

According to the overload detection device 109 and method for the orbital crusher 110 according to the present embodiment, the detection period T1 is set, and the hydraulic pressure in the detection period T1 is higher than the pressure threshold value α at the rate of the time T2. , to estimate the load state of the orbital crusher 110 . By setting the detection period T1 in this manner, the influence of short-term fluctuations in the hydraulic pressure P is suppressed. As a result, erroneous detection of an overload state can be suppressed. Therefore, it is possible to detect with high accuracy that the crusher 110 is being operated in an overloaded state while using the measured value of the hydraulic pressure P, which fluctuates steadily.

Further, in the overload detection device 109 and method for the gyration-type crusher 110 according to the present embodiment, the pressure threshold α for the hydraulic pressure in the current _sampling section _{Sn is} It is a value obtained by multiplying the moving average Pm including the detection value of _-1 by a coefficient C of 1 or more.

As a result, the value of the pressure threshold α is given corresponding to the hydraulic pressure P that constantly fluctuates due to changes in raw material properties, raw material size, raw material moisture content, and the like. Therefore, the influence of short-term fluctuations in hydraulic pressure can be more effectively suppressed.

Preferred embodiments (first and second embodiments) of the present invention have been described above. can also be included in the present invention.

For example, in the above embodiment, it is determined whether the operation of the gyration crushers 10, 110 is in an overload state or a steady state based on the ratio R of the integrated value T2 to the detection period T1. Alternatively, the overload detectors 9 and 109 store a reference value related to the integrated value T2 in advance, and when the integrated value T2 exceeds the reference value, the operation of the gyration crusher 10 and 110 is overloaded. It may be determined that the state

Further, for example, in the above-described embodiment, the integrated value T2 of the time during which the hydraulic pressure exceeds the predetermined pressure threshold α is obtained within the detection period T1. However, instead of the integrated value T2 of time, an integrated value of hydraulic pressure exceeding a predetermined pressure threshold value α (that is, the area of the hatched portion in FIG. 5) is obtained within the detection period T1 and compared with the predetermined threshold value. By doing so, the overload condition of the orbital crusher 10, 110 may be determined.

Further, for example, in the above embodiment, the pressure threshold for the hydraulic pressure in the sampling interval is a value obtained based on the moving average including the detected values in the sampling interval immediately before the sampling interval. It is not limited to this. For example, the pressure threshold for the hydraulic pressure in the sampling interval may be the latest time average value obtained based on the detected values in a plurality of sampling intervals before the sampling interval. Alternatively, the pressure threshold for the hydraulic pressure in the sampling interval may be a value obtained by applying a predetermined first-order lag filter to the detected values in a plurality of sampling intervals including the sampling interval immediately preceding the sampling interval. In either case, it is possible to provide a pressure threshold corresponding to the hydraulic pressure that constantly fluctuates, and to suppress the influence of short-term fluctuations in the hydraulic pressure.

1: Cone cable support assembly 2: Frame assembly 3: Spindle assembly 4: Frame cylinder (hydraulic cylinder)
4a: first hydraulic chamber 4b: second hydraulic chamber 6: eccentric sleeve assembly 8: bearing cylinder (hydraulic cylinder)
9, 109: Overload detection devices 9a, 109a: Arithmetic devices 9b, 109b: Storage devices 10, 110: Orbital crusher 11: Input hopper 12: Cone cave 13: Gear plate 14: Cone cave support 18: Electric motor 19: Power transmission mechanism 21 : Upper frame 22 : Lower frame 23 : Set adjustment base 24 : Gear 25 : Dust rings 26, 126 : Set sensor 27 : Motor 31 : Main shaft 33 : Mantle core 34 : Mantle 41 : Hydraulic sensors 42, 92 : Accumulators 44, 144 : Cylinder control device 47 : Crushing chamber 61 : V pulley 62 : Horizontal shaft 63 : Bevel pinion 64 : Bevel gear 65 : Eccentric sleeves 70, 90 : Hydraulic circuit 71 : Oil tank 72 : First oil passage 73 : Second 2 Oil passage 74 : Drainage passage 75 : Oil supply passage 76 : Gear pump 77 : Pump motor 78 : Switching valve 80 : Set adjusting device 81 : Ram 82 : Main shaft thrust bearing 83 : Cylinder tube 85 : Hydraulic chamber 86 : Hydraulic sensor 91 : Communicating pipe 93 : Oil supply pipe 94 : Oil drain pipe 98 : On-off valve 99 : On-off valve

Claims (5)

A mantle fixed to a main shaft that makes an eccentric orbital motion; a cone cavity that forms a crushing chamber between the mantle and the mantle for crushing raw stones; A device for detecting that an orbital crusher comprising a hydraulic cylinder that applies hydraulic force against the crushing force to the cone cave is being operated in an overloaded state,
a hydraulic sensor that detects the hydraulic pressure of the hydraulic cylinder;
a storage device that acquires information about the hydraulic pressure from the hydraulic sensor and stores the information in association with a sampling time;
When a plurality of consecutive sampling intervals are defined as a detection period, the time during which the hydraulic pressure exceeds a predetermined pressure threshold is accumulated, and the ratio of the accumulated time to the detection period exceeds the predetermined ratio threshold and a computing device that detects that the crusher is operating in an overloaded state,
Overload detection device for gyration crusher. The pressure threshold for the hydraulic pressure in the sampling interval is a value obtained by multiplying a moving average including detected values in the sampling interval immediately preceding the sampling interval by a coefficient of 1 or more.
An overload detection device for a gyration crusher according to claim 1. mantle and
a main shaft on which the mantle is fixed and eccentrically rotated;
a lower frame supporting the main shaft;
a cone cavity forming a crushing chamber between the mantle and the mantle, in which the ore is bitten and crushed;
an upper frame supporting the cone cave;
a hydraulic cylinder that provides hydraulic force against crushing forces to the mantle or cone to hold a predetermined set of the mantle and cone;
and the overload detection device according to claim 1 or 2,
Orbital crusher. A mantle fixed to a main shaft that makes an eccentric orbital motion; a cone cavity that forms a crushing chamber between the mantle and the mantle for crushing raw stones; A method for detecting that an orbiting crusher comprising a hydraulic cylinder for applying hydraulic force to the cone cave against the crushing force is being operated in an overloaded state, comprising:
detecting the hydraulic pressure of the hydraulic cylinder and storing the hydraulic pressure in association with a sampling time;
A plurality of consecutive sampling times are defined as a detection period, the time during which the hydraulic pressure exceeds a predetermined pressure threshold is accumulated, and the ratio of the accumulated time to the detection period exceeds the predetermined ratio threshold. , detecting that the crusher is operating in an overload condition;
Overload detection method for gyration crusher. The pressure threshold for the hydraulic pressure at the sampling time is a value obtained by multiplying a moving average including the detected value at the sampling time immediately before the sampling time by a coefficient of 1 or more.
An overload detection method for a tumbling crusher according to claim 4.

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