Patent Application
20150076259
The invention relates to an apparatus and a method for monitoring and controlling a crusher, a crusher and a method for adjusting a crusher. The invention relates particularly, though not exclusively, to protecting a gyratory or cone crusher from uncrushable material.
Rock is gained from the earth for crushing by exploding or excavating. Rock can also be natural and gravel or construction waste. Mobile crushers and stationary crushing applications are used in crushing. An excavator or wheeled loader loads the material to be crushed into the crusher's feed hopper from where the material to be crushed may fall into the crusher or a feeder moves the rock material towards the crusher.
Mineral material is crushed in gyratory and cone crushers by moving an inner blade (crushing cone) relative to an outer blade. The inner and outer blades define therebetween a crushing chamber. Commonly gyratory and cone crushers are adjusted for different types of production requirements by changing profile of the crushing chamber, amount of eccentric motion of the crushing cone or stroke, rotational speed of the crushing cone and setting of the crusher.
Crushing capacity of a gyratory and cone crusher is aimed to be used economically fully so that the crusher is loaded continuously with a high crushing power and simultaneously the used crushing power is directed for producing the planned product distribution. Interruptions in the crushing event (e.g. caused by overload) reduce efficiency.
Ending up of uncrushable or very hard material in a crushing chamber is disadvantageous. In such a case, an overload situation may arise in the crushing chamber and the crushing blade(s) may be damaged. In order to overcome the problem, the setting of the crusher has to be opened and the movable crushing blade has to be moved farther away from the fixed crushing blade. A concrete reinforcing bar is an example of adverse material which may end up in the crushing chamber when separating of material before the crushing is incomplete. Adverse is also material having unequal distribution and containing large pieces. Furthermore, the amount and location of the material in the crushing chamber affects the power intake of the crusher.
WO2009008796A1 shows a measuring apparatus for indicating the load in a gyratory crusher.
It is an object of the invention to provide an alternative way for indicating the load of a gyratory or cone crusher during crushing. It is an object of the invention to provide a simple way for indicating the load present in a crushing chamber. It is an object of the invention to improve adjusting chances of the crushing event. It is an object of the invention to improve usability and efficiency of the crusher.
According to a first aspect of the invention there is provided a method for monitoring a gyratory or cone crusher, comprising:
Preferably the load of the crusher is determined by a pressure measurement.
Preferably the load of the crusher is determined by a power measurement.
Preferably an average of the load of the crusher corresponding to every determined rotational position of the inner blade of the crusher is determined from a period of several measuring revolutions.
Preferably the triggering from the main shaft of the crusher is implemented by a magnetic detector or switch. The triggering from the main shaft of the crusher may be implemented by a detector or switch which may be inductive, capacitive, optical, based on ultrasound or based on electromagnetic radiation.
Preferably the triggering from the drive shaft of the crusher is implemented by a magnetic detector or switch. The triggering from the drive shaft of the crusher may be implemented by a detector or switch which may be inductive, capacitive, optical, based on ultrasound or based on electromagnetic radiation.
Preferably the load of the crusher corresponding to each rotational position of the inner blade is presented on a screen to be observed by an operator.
According to a second aspect of the invention there is provided a system for monitoring a crusher, comprising:
Preferably the system comprises an output to a screen for presenting
Preferably the system comprises a screen on which is presented
Preferably the said rotational positions of the inner blade of the crusher and the loads corresponding to said rotational positions or the averages of the loads are presented on a polar coordinate system.
Preferably the rotational position of the inner blade of the crusher is presented as a rotation angle.
Preferably the measuring apparatus suitable for measuring the load is measuring pressure.
Preferably the measuring apparatus suitable for measuring the load is measuring power.
Preferably the detector suitable for detecting the element to be placed on the main shaft is a magnetic detector. The detector may be inductive, capacitive, optical, based on ultrasound or based on electromagnetic radiation.
Preferably the detector suitable for detecting the elements to be placed on the drive shaft is a magnetic detector. The detector may be inductive, capacitive, optical, based on ultrasound or based on electromagnetic radiation.
According to a third aspect of the invention there is provided a method for monitoring a gyratory or cone crusher, which gyratory or cone crusher comprises a crushing chamber and a feed opening of the crushing chamber and an adjusting apparatus, wherein one or more movable adjusting parts comprised by the adjusting apparatus are arranged in connection with the feed opening and in which method a flow area of material to be crushed and flowing through the feed opening to the crushing chamber is adjusted during crushing by moving adjusting parts such that the flow area is decreased as a response to detecting an increase of an average load by a method or system according to an aspect of this invention, and the flow area is increased as a response to detecting a decrease of the average load by a method or system according to an aspect of this invention.
Preferably the feed of the material is adjusted during crushing in the method so that the amount of the material is increased at a rotational position of the inner blade which corresponds to a low load and is detected by a method or system according to an aspect of this invention.
According to a fourth aspect of the invention there is provided a system for monitoring and controlling a gyratory or cone crusher, which gyratory or cone crusher comprises a crushing chamber and a feed opening of the crushing chamber, a load monitoring system according to an aspect of this invention, and an adjusting apparatus, wherein one or more movable adjusting parts comprised by the adjusting apparatus are arranged in connection with the feed opening and which adjusting apparatus is configured to adjust during crushing a flow area of material to be crushed and flowing through the feed opening to the crushing chamber by moving adjustment parts such that the flow area is decreased as a response to an average load detected by a method or a system according to an aspect of this invention increasing, and the flow area is increased as a response to the average load detected by a method or a system according to an aspect of this invention decreasing.
Preferably the adjusting apparatus is configured to adjust feed of the material during crushing so that amount of the material is increased at a rotational position of the inner blade which corresponds to a low load and is detected by a method or system according to an aspect of this invention.
According to a fifth aspect of the invention there is provided a pressing crusher suitable for mineral material crushing such as a gyratory or cone crusher which comprises a crushing chamber and a feed opening of the crushing chamber, and the crusher comprises a system for monitoring the crusher according to an aspect of this invention, and an adjusting apparatus according to an aspect of this invention comprising one or more movable adjusting parts to be arranged in connection with the feed opening which one or more movable adjusting parts are movable during crushing to adjust a flow area of material to be crushed and flowing through the feed opening to the crushing chamber, and the one or more adjusting parts are configured to move so that the flow area is decreased as a response to the load detected by the system increasing, and the flow area is increased as a response to the load detected by the system decreasing.
Preferably the adjusting apparatus is configured to adjust the feed of the material during crushing so that amount of the material is increased at a rotational position of the inner blade which corresponds to a low load and is detected by a method or system according to an aspect of this invention.
Preferably the crusher comprises a crusher drive and a feedback control system which comprises a monitoring system and moving means of the adjustment parts for adjusting the adjustment parts based on detections of the monitoring system.
Preferably the crusher is a gyratory or cone crusher.
According to a sixth aspect of the invention there is provided a crushing plant which comprises a crusher according to an embodiment of this invention.
According to a seventh aspect of the invention there is provided a method for adjusting a pressing crusher which is suitable for mineral material crushing such as a gyratory or cone crusher, or a crushing plant, which gyratory or cone crusher or crushing plant comprises a crushing chamber and a feed opening of the crushing chamber, and an adjusting apparatus comprising one or more movable adjusting parts which are arranged in connection with the feed opening, and which gyratory or cone crusher or crushing plant comprises a system for monitoring the crusher according to an aspect of this invention, and in which method a flow area of material to be crushed and flowing through the feed opening to the crushing chamber is adjusted by moving the adjusting parts so that the flow area is decreased as a response to the load detected by the monitoring system increasing, and the flow area is increased as a response to the load detected by the monitoring system decreasing.
Preferably the gyratory or cone crusher comprises a crusher drive and a feedback control system which comprises a monitoring system according to an aspect of this invention and moving means of the adjustment parts so that in the method the load of the gyratory or cone crusher is monitored by the monitoring system according to an aspect of this invention, and the adjustment parts are moved based on detected load.
Preferably feed of the material is adjusted during crushing such that amount of the material is increased at a rotational position of the inner blade which is corresponding to a low load and is detected by a method or system according to an aspect of this invention.
Different embodiments of the present invention will be illustrated or have been illustrated only in connection with some aspects of the invention. A skilled person appreciates that any embodiment of an aspect of the invention may apply to the same aspect of the invention and other aspects alone or in combination with other embodiments as well.
The invention will be described, by way of example, with reference to the accompanying drawings, in which:
In the following description, like numbers denote like elements. It should be appreciated that the illustrated drawings are not entirely in scale, and that the drawings mainly serve the purpose of illustrating embodiments of the invention.
Preferably the crushing station comprises a feed hopper above a feed opening of a crushing chamber of the crusher 200 (not shown in the Figures). While the crushing process is running the material to be crushed is fed (for instance by a loader) to a feeder 103, from where it is further fed to the crusher 200. The feeder 103 may also be a so called scalper or a conveyor may be connected in connection with the feeder (not shown in the Figures). The material to be crushed arriving from the feeder/conveyor is guided by the feed hopper into the feed opening of the crushing chamber. The material to be crushed may be fed also directly to the feed hopper, for example by a loader.
The crushing station 100 further comprises a monitoring system 214.
Preferably the crushing station comprises also an adjusting apparatus of the feed opening of the crusher (not shown in the Figures). The adjusting apparatus is located above the feed opening so that flow of the material to be crushed to the underlying crushing chamber 225 can be adjusted. The adjusting apparatus comprises an adjustable feed opening which is implemented by arranging movable adjusting parts in connection with the feed opening. The flow opening can be increased or decreased or its center point can be moved. The adjusting apparatus may be operated manually by an operator or it may be connected to an automatic adjusting system. The adjusting apparatus may be connected to the monitoring system 214, wherethrough the crusher can be adjusted based on a load detected by the monitoring system 214. For instance, a flow area of the feed opening is decreased when the load detected by the monitoring system is increasing and the flow area of the feed opening is increased when the load detected by the monitoring system 214 is decreasing. The location of the feed opening can also be changed during crushing so that the feed opening is moved in a direction corresponding to a rotational location of a main shaft 203 corresponding to a low load detected by the monitoring system. According to an embodiment, a conveyor feeding material to the crusher (not shown in the Figures) may be moved such that the material dropping into the crusher from the conveyor is guided into the crushing chamber 225 in the direction corresponding to a rotational location of the main shaft 203 corresponding to a low load detected by the monitoring system. Alternatively, feeding the material to the direction corresponding to a rotational location of the main shaft 203 corresponding to a low load detected by the monitoring system may be arranged by another known method by which feeding of the material into the crushing chamber 225 is increased such that the amount of the material is increased in a detected rotational location of the inner blade corresponding to a low load.
A measuring apparatus is located on the main shaft and consists of a first element 212 to be fixedly placed on the shaft and a first detector 213. The first detector 213 is connected to the monitoring system 214. A measuring apparatus is located on the drive shaft and consists of at least one second element 208,209, 210 fixedly placed on the shaft and a second detector 211. The second detector 211 is connected to the monitoring system.
The first and second detectors 211,213 may be like or different. The detectors may be inductive switches which detect proximity of the element 208,209,210,212 made of suitable material and placed on the shaft.
The detectors 211,213 may be capacitive switches which detect proximity of the element 208,209,210,212 made of suitable material and placed on the shaft.
The detectors 211,213 may be optical switches which detect proximity of a reflective element 208,209,210,212 placed for example on the shaft.
The detectors 211,213 may be switches based on ultrasound which detect proximity of an element 208,209,210,212 placed for example on the shaft and reflecting ultrasound.
The detectors 211,213 may be switches based on electromagnetic radiation which detect proximity of an element 208,209,210,212 placed for example on the shaft and reflecting electromagnetic radiation.
The load of the crusher is measured by a measuring apparatus 215 which measures the power of the crusher or the pressure of the crushing chamber 225 or both. The measuring apparatus measuring the load is implemented by conventional methods. For example, the pressure of the crushing chamber 225 can be measured from the hydraulic fluid loading the main shaft 203 from below.
The power measurement of the crusher can be arranged for example from the current of an electric motor comprised preferably by the motor unit 104. The measuring apparatus 215 is connected to the monitoring system 214.
Here, the pulse means any common signal which is transmitted from the detector or corresponding measuring apparatus or switch to the monitoring system 214 or the like. The detector 211 may transmit for example a voltage of −5V to the monitoring system 214 when the element 208,209,210 is not at the position of the detector 211 and a voltage of +5V when the element 208,209,210 is at the position of the detector. The signal may be for example a conventional standard message or the like, that enables a simple design of the monitoring system and compatibility with conventional automation systems or the like.
The elements 208,209,210 are located fixedly on the drive shaft in predefined locations. Fixedly means in this context that the location of the elements 208,209,210 may be changed as needed but the locations are not changed while the apparatus is in operation. The fixed mounting of the elements 208,209,210 enables that the predefined locations of the elements, i.e. the rotational locations of the drive shaft corresponding to the locations of the elements, are saved in advance in the monitoring system 214, wherethrough a separate computing for determining the rotational position is not necessary while the apparatus is in operation. The elements 212 located on the main shaft 203 are located fixedly in a corresponding manner.
A transmission of the main shaft 203 and the drive shaft 206 of the crusher is implemented for example so that substantially four revolutions of the drive shaft 206 correspond to a full revolution of the main shaft 203. Thus, during one measuring revolution, i.e. one full revolution of the main shaft 203, each element 208,209,210 located on the drive shaft is detected substantially four times by the detector 211. In an example case in which three elements 208,209,210 are located on the drive shaft, during the measuring revolution twelve triggerings corresponding to the rotational position of the inner blade are received from the detector 211, i.e. the load of the crusher 200 can be determined in twelve directions. The transmission of the main shaft 203 and the drive shaft is not precisely an integer so that the triggers during successive measuring revolutions do not exactly correspond to the same rotational positions of the inner blade.
The screen on which the rotational location of the main shaft 203 and the corresponding load of the crusher is presented may be located as part of the monitoring system 214 or be part of an automation system of the entire crusher or crushing plant or the like. The monitoring system 214 may comprise an output for the screen for presenting the detections.
As the index depicting the rotational location of the main shaft 203 is increased by one, steps 303, 304, 305, 306 and 307 of the method are repeated until the pulse MS of the main shaft is readable in step 305, at which time the index N depicting the rotational location of the drive shaft 203 is set to zero 308, after which the steps 303, 304, 305, 306 and 307 of the method are repeated again.
In the monitoring method it is not necessary to measure time or rotational speed of the shafts of the crusher because the elements 208,209,210,212 of both the main shaft 203 and the drive shaft 206 of the crusher which are detected by the detectors 211,213 are fixedly mounted to predefined locations. In the monitoring method, the load of the crusher is determined in the rotational positions of the inner blade 201 of the crusher. The rotational position, or certain rotational positions, are found out from the pulses given by elements 208,209,210,212 fixedly mounted on the main shaft 203 and the drive shaft 206, and the detectors 211,213 used for detecting the elements. The monitoring method does not require complex computation or particular computing arrangements that for example a determination of the rotational position by measuring time and rotational speed would require.
The rotational positions 112,114 of the main shaft 203 and the loads 113,115 of the crusher corresponding to these rotational positions are presented in a kind of a polar coordinate system on the screen of
In each rotational position, the presented load may be either the latest momentary value or an average value of detected loads of the rotational position in question which loads are measured from several revolutions of the main shaft 203. On the screen may be presented, for example, also the highest and lowest level of the loads, or for example simultaneously both the average and the momentary value or all previously mentioned at the same time.
A maximum load limit 110 of the crusher and a limit 111 depicting a desired load or the like of the crusher are presented also on the screen.
The load 115 detected in the rotational position 114 is clearly higher than the loads detected in the other rotational locations in the situation of the screen of
The detected higher load may be caused by uncrushable material ending up in the crushing chamber. The detected higher load during several measuring revolutions on a certain sector corresponding to a rotational position of the inner blade enables reacting to the ending up of uncrushable material into the crushing chamber already before a load peak overriding safety limits would cause measures. Preferably the reaction can be initiated already from the first load peak which can be measured from both the power and the pressure.
The load of the crusher is monitored with the monitoring system 214 in the rotational positions of the main shaft 203. Information on the load of the crusher from the monitoring system 214 is used to adjust the crushing event. The adjustment may take place with actions of the operator or automatically with suitable adjustment solutions. An object of the adjustment of the crushing event is among others an even loading in all rotational positions of the main shaft 203, a sufficiently high load for ensuring an efficient crushing event and detecting of uncrushable or very hard material before damaging of the crusher.
The foregoing description provides non-limiting examples of some embodiments of the invention. It is clear to a person skilled in the art that the invention is not restricted to details presented, but that the invention can be implemented in other equivalent means. Some of the features of the above-disclosed embodiments may be used to advantage without the use of other features.
As such, the foregoing description shall be considered as merely illustrative of the principles of the invention, and not in limitation thereof. Hence, the scope of the invention is only restricted by the appended patent claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 20125398 | Apr 2012 | FI | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/FI2013/050397 | 4/11/2013 | WO | 00 |
