Method for determining the layer height of a feed material supplied to a crushing and/or screening plant of a material processing device

Abstract

The invention relates to a method for determining the layer height of a feed material, which is supplied to a crushing and/or screening plant of a material processing device, wherein a conveyor device is used to convey the feed material in a conveying direction, wherein a sensor array comprising a plurality of sensors is used to determine the layer height of the feed material. A reliable method that can be performed with little effort and without impairing the operation of the material processing device is achieved by the longitudinal axes of the detection volumes of the sensors extending at least partially in and/or counter to the conveying direction.

Claims

1-17. (canceled)

18. A method for determining a layer height of a feed material supplied to a crushing and/or screen plant of a material processing device, the method comprising: conveying the feed material in a conveying direction on a conveyor; detecting signal waves reflected from the feed material with a sensor array including a plurality of sensors, each sensor having an associated detection volume having a longitudinal axis extending in a direction of a length of the detection volume, each of the longitudinal axes of the detection volumes extending at least partially in and/or counter to the conveying direction; and determining the layer height of the feed material based at least in part on the detected signal waves.

19. The method of claim 18, wherein: each of the sensors is configured to detect whether feed material is located in a layer height range associated with the respective sensor.

20. The method of claim 18, wherein: the determining of the layer height is based only on feed material within a set gauge distance from the sensors.

21. The method of claim 18, wherein: the sensors are disposed transversely with respect to the conveying direction, one above the other in a direction of gravity.

22. The method of claim 18, wherein: the longitudinal axes of the detection volumes extend at an angle of smaller than 45° with respect to the conveying direction.

23. The method of claim 18, wherein: the longitudinal axes of the detection volumes extend at an angle of smaller than 30° with respect to the conveying direction.

24. The method of claim 18, wherein: the longitudinal axes of the detection volumes extend at an angle of smaller than 15° with respect to the conveying direction.

25. The method of claim 18, wherein: the sensors are selected from the group consisting of radar sensors, ultrasonic sensors, laser distance sensors and laser Doppler vibrometers.

26. The method of claim 18, wherein: the determining of the layer height is based only on feed material within a set gauge distance from the sensors; the measuring volumes do not overlap within the set gauge distance; and the detection volumes each have a vertical opening angle smaller than 10°.

27. The method of claim 26, wherein: the vertical opening angle is smaller than 7.5°.

28. The method of claim 26, wherein: the vertical opening angle is smaller than 5°.

29. The method of claim 18, wherein: the sensors of the sensor array are separate sensors.

30. The method of claim 18, wherein: the sensor array includes a housing and the sensors are at least partially received in the housing.

31. The method of claim 18, further comprising: determining a speed of the feed material using a speed sensor.

32. The method of claim 31, wherein: the speed sensor comprises at least one of the sensors of the sensor array.

33. The method of claim 32, wherein: the speed of the feed material is determined as an average speed determined by a plurality of the sensors of the sensor array.

34. The method of claim 31, further comprising: determining a volumetric flow rate of the feed material from the speed of the feed material, the layer height of the feed material and a geometry of the conveyor.

35. The method of claim 34, further comprising: determining a rock type and/or a feed size of the feed material based at least in part on a reflection property of the feed material detected by the sensors.

36. The method of claim 34, further comprising: determining an anticipated dwell time of the feed material in the crushing and/or screening plant based at least in part on the rock type and/or the feed size of the feed material and based at least in part on the volumetric flow rate of the feed material; and regulating an effective conveying speed of the conveyor based at least in part on the anticipated dwell time.

37. The method of claim 34, further comprising: regulating an effective conveying speed of the conveyor based at least in part on the volumetric flow rate.

38. A material processing device, comprising: a crushing and/or screening plant; a conveyor configured to convey feed material in a conveying direction to the crushing and/or screening plant; and a sensor array including a plurality of sensors configured to detect signal waves reflected from the feed material to determine a layer height of the feed material on the conveyor, each sensor having an associated detection volume having a longitudinal axis extending in a direction of a length of the detection volume, the sensors being oriented such that longitudinal axes of the detection volumes extend at least partially in and/or counter to the conveying direction.

39. The material processing device of claim 38, wherein: the sensors are disposed at a distance from the conveyor in and/or counter to the conveying direction.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The invention is explained in greater detail below based on an exemplary embodiment shown in the drawings. In the Figures:

[0035] FIG. 1 shows a lateral, partially cut schematic representation of a material processing device and

[0036] FIG. 2 shows a schematic representation of a sensor array consisting of several sensors with their respective detection volumes.

DETAILED DESCRIPTION

[0037] FIG. 1 shows a lateral, partially cut schematic representation of a material processing device 10. The material processing device 10 can be designed as a mobile unit having a chassis 11 and for instance a chain drive 13. The material processing device 10 may comprise a crushing plant 50 and/or a screening plant 30.

[0038] A hopper 21, which may have hopper walls 22, may further be provided at the material processing device 10, in particular at a feed unit 20. The hopper 21 may be used to receive feed material 70 from an upstream conveyor, such as an excavator, wheel loader, or belt conveyor, and direct it onto a conveyor device 23.

[0039] The crushing plant 50 and/or the screening plant 30 can be supplied with feed material 70 for processing in a conveying direction F by means of the conveyor device 23. In this case, the conveyor device 23 is designed as a vibratory feeder. However, other embodiments of a conveyor device 23, in particular as a conveyor belt, are also conceivable. The conveyor device 23 may also be referred to as a conveyor 23.

[0040] The screening plant 30 may, for instance, be connected upstream of the crushing plant 50 as a pre-screen unit. The pre-screen unit may comprise a heavy-duty double-deck screen 31, which may have an upper deck 32 designed as a coarser screen and a lower deck 34 designed as a finer screen. A drive 33 causes it to vibrate in a circular motion. The upper deck 32 can separate a fine fraction 71 and a medium fraction 72 from the material to be crushed 73. The lower deck 34 can separate the fine fraction 71 from the medium fraction 72. The fine fraction 71 can optionally be discharged from the material crusher plant 10 or be fed to the medium fraction 72 for instance by setting a bypass flap accordingly. The medium fraction 72 can be routed to a crusher discharge conveyor 40 past the crusher 50 via a bypass. The material to be crushed 73 is routed to the crusher 50 via a crusher inlet at the end of the pre-screen unit.

[0041] The material processing device 10 may comprise a crushing plant 50 configured as a jaw crusher. However, it is also conceivable to provide other types of crushing plants 50, for instance impact crushers, gyratory crushers or cone crushers. The crushing plant 50 may comprise a stationary crushing jaw 51 and a moving crushing jaw 52, which may be oriented to converge at an angle such that a conical tapered shaft is formed therebetween. The shaft may open out into a crushing gap 56. For instance, the crushing plant 50 may be driven by a drive unit 12 via a drive shaft 55 connected to an eccentric 54.

[0042] The eccentric 54 moves the moving crushing jaw 52 towards and away from the stationary crushing jaw 51 in an elliptical motion. In the course of such a stroke, the distance between the crushing jaws 51, 52 in the area of the crushing gap 56 also changes. The motion of the moving crushing jaw 52 causes the material 73 to be crushed to be crushed further and further along the conical shaft until it reaches a grain size that allows it to exit the shaft through the crushing gap 56. The crushed material 74 falls onto the crusher discharge belt 40, which is used to convey it along. Provision can also be made, for instance, for it to pass a magnetic separator 41, which separates ferromagnetic components from the shredded material 74 and ejects them laterally.

[0043] As further shown in FIG. 1, a level sensor 61 may be assigned to the crushing plant 50. The latter can be designed as an ultra-sound sensor. However, it is also conceivable to use other types of sensors, such as optical sensors (for instance, a camera system) or mechanically acting sensors. The level sensor 61 may monitor the level of material 73 to be crushed in the crusher 50. It may be part of a continuous feed control system of the material processing equipment 10. For this purpose, the material feeding components of the material processing device 10, in particular the conveyor device 23, can be actuated based on the signals of the level sensor 61. This can be used, for instance, to regulate the volumetric flow rate of the material 73 to be crushed that is fed to the crusher 50.

[0044] As can be further seen in FIG. 1, a sensor array 105 comprising several sensors 101 may be provided on the material processing device 10. The sensor array 105 can be used to determine a layer height of the feed material 70. In the illustrated exemplary embodiment, the sensor array 105 comprises three individual sensors 101 disposed one above the other adjacent to each other in the direction of gravity. Of course, other arrangements and in particular different numbers of sensors 101 are also conceivable. Furthermore, the sensor array 105 need not be individual sensors 101; rather, the sensor array 105 may also be formed as a structural unit. In particular, the assembly may comprise a housing 105a that at least partially houses the structural unit. The sensors 101 may be at least partially received in the housing 105a.

[0045] A sensor holding device 110 may be used to hold the sensor array 105 at the material processing device 10. The sensor holding device 110 may be a pole, to which the sensor array 105 is attached. A sensor adjustment device 111 may be used to indirectly or directly attach the sensor array 105 to the material processing device 10. In this case, the sensor holding device 110 is used to attach the sensor 105 to the material processing device 10 using a sensor adjustment device 111. For instance, the sensor adjustment device 111 may enable an articulated connection to the sensor holding device 110 such that the sensor array 105 can be swiveled, for instance, to permit different orientations of the sensor array 105. It is also conceivable to attach the sensor array 105 to the material processing device 10 and/or the sensor holding device 110 in a height-adjustable manner.

[0046] In the exemplary embodiment shown, the sensors 101 are radar sensors. However, other sensors, in particular ultrasonic sensors, laser distance sensors and/or laser Doppler sensors, in particular laser Doppler vibrometers, are also conceivable. The sensors 101 may emit waves, in this case radar waves, for instance inside a detection volume 103. If there is material, in particular feed material 70, within the detection volume 103 of a sensor 101, the waves may be reflected therefrom. A portion of the reflected waves is reflected back along the detection volume 103 to the respective sensors 101 and can be detected by them.

[0047] As can be seen in FIG. 1, the conveying direction F can be oriented horizontally, for instance. However, inclined conveying directions F are also conceivable, for instance, if the conveyor device 23 is inclined. As shown in FIG. 2, the detection volumes 103 may be lobe-shaped and/or tapered. In this case, they are designed to be radar lobes. However, deviating geometries of the detection volumes 103 are also conceivable. Every detection volume 103 may have a longitudinal axis 107. The longitudinal axis 107 may be the bisector of a vertical opening angle β of the detection volume 103.

[0048] The longitudinal axes 107 of the detection volumes 103 are oriented at least partially in the direction of the conveying direction F and/or counter thereto. As can be seen from FIG. 2, the longitudinal axes 107 each forms an angle α with the conveying direction F. The smaller this angle α is, the larger is, in terms of magnitude, the component of the direction of the longitudinal axis 107 of the respective detection volumes 103 in the direction and/or counter to the direction of the conveying direction F.

[0049] The sensors 101 and/or their detection volumes 103 may be oriented such that the longitudinal axes 107 of adjacent detection volumes 103 form an angle γ with each other, as further shown in FIG. 2. In this case, diverging longitudinal axes 107 result from the angles γ. This can be achieved, for instance, by arranging the sensors 101 in a convexly arched sensor arrangement 106.

[0050] As further shown in FIG. 2, a layer height range 120 may be assigned to every sensor 101. For instance, the layer height range 120 of a sensor 101 may be a range between a lower layer height to be detected and an upper layer height to be detected that is present in the detection volume 103 of the sensor 101 in the range of a set gauge distance 108.

[0051] For this purpose, provision can be made for a sensor 101 to evaluate, for instance, only a signal that is detected in an area within the set measuring distance 108. It can be determined, for instance, by means of a pulse time delay method. For instance, an evaluation device, which is not shown in the figures, can be provided for evaluating the pulse time delays.

[0052] A set gauge distance can be dimensioned along the conveying direction F, for instance.

[0053] As can be further seen in FIG. 2, the detection volumes 103 of the sensors 101 may be configured and/or oriented such that they do not overlap or overlap only slightly within the set gauge distance 108. In particular, the angles α, β, γ and the set gauge distance 108 can be matched accordingly for this purpose.

[0054] If, for instance, the layer height of the feed material 70 is now to be determined during operation of the material processing device 10, the sensors 101 can emit measuring waves, in particular radar waves, which are at least reflected by the feed material 70. The reflected measurement waves are then detected by the sensor 101 along whose detection volume 103 they are reflected. Of course, waves other than radar waves can also be used. Furthermore, preferably only signals reflected from the feed material 70 that is within the set gauge distance 108 are detected and/or evaluated.

[0055] For instance, a sensor 101 may then detect the presence of feed material 70 if any waves are reflected as a signal to the sensor 101. It is also conceivable to define a threshold value for an intensity of the signal, above which the presence of feed material 70 is to be expected. The signal can be evaluated, for instance, by means of an evaluation device that is not shown in the figures. However, the evaluation may also be performed by the sensors 101 themselves.

[0056] Every sensor 101 can thus detect whether there is feed material 70 within the set gauge distance 108 and within the layer height range 120 assigned to the sensor(s) 101. Consequently, information from several sensors 101 can be used to infer the presence of several layer height ranges 120 containing feed material 70, and thus the layer height of feed material 70.

[0057] Every sensor 101 can be used to determine the speed of the feed material 70, particularly if there is feed material 70 in the layer height range 120 assigned to the sensor. For this purpose, for instance, a Doppler speed measurement can be used. The measurement signals for speed determination can be evaluated by the sensors 101 or by an evaluation device.

[0058] The geometry of the conveyor device 23, the layer height of the feed material 70 and the speed of the feed material 70, can be used to determine a material flow, in particular a volumetric flow of the feed material 70. Provision may be made to use the volumetric flow rate of the feed material 70 to regulate the material processing device 10, in particular to regulate a fed material flow rate. For this purpose, a regulation device may be provided at the material processing device 10, which is not shown in the figures.