Device for the metered feeding of free-flowing bulk materials, control and regulation of such devices and sensor for such a device

Abstract

Device for the metered feeding of free-flowing bulk materials such as plastic granules, additives, color components for masterbatches, regenerated or new materials, PVC dry blends, powders, in color change devices, dosing systems, volumetric or gravimetric mixing systems, with one or more storage containers (2) for the bulk material fed to a motor-driven conveying device, for example a motor-driven conveyor screw (5), with a sensor (10) assigned to the associated storage container (2) which is adjustable and calibrated to a predetermined, adjustable bulk material filling height designed as a bulk material conveying height, for example a maximum and / or minimum bulk material conveying height (8, 9), in the respective storage container (2),whose measuring and radiation surface (15) facing the surface of the bulk material for a measuring beam (11) can be kept free of bulk material deposits continuously or intermittently by an adjustable gas flow under overpressure provided by a gas source (14).

Description

TECHNICAL AREA

[0001] The invention relates to a device for metered feeding of free-flowing bulk materials, a control and regulation system for such devices, and a sensor in such devices. STATE OF THE ART

[0002] Sensors are state of the art; for example, so-called Time-Of-Flight sensors from VL53L1X are already known.

[0003] When feeding and / or mixing free-flowing bulk materials such as plastic granules, additives, color components for masterbatches, regenerates or virgin materials, for example PVC dry blends, powders, in color change devices and dosing systems, it is often crucial to adhere precisely to the various bulk material quantities.

[0004] The invention is therefore based on the objective of creating a device for the metered feeding of free-flowing bulk materials, by means of which such requirements can be met within certain tolerance limits. TASKS

[0005] The invention is based on the objectives of creating a device for the metered feeding of bulk materials for various applications, enabling precise metering.

[0006] Furthermore, the invention is based on the objective of creating a control or regulation system for such devices.

[0007] Finally, the invention is based on the objective of proposing a sensor arranged in a device according to the invention. SOLUTION TO THE TASK CONCERNING THE DEVICE

[0008] This task is solved by a device for the metered feeding of free-flowing bulk materials such as plastic granules, additives, color components for masterbatches, regenerates or virgin materials, PVC dry blends, powders, in color change devices, dosing systems, volumetric or gravimetric mixing systems, with one or more storage containers for the bulk material fed to a motor-driven conveying device, for example, a motor-driven screw conveyor, with a sensor assigned to the associated storage container, which is adjustable and calibratable at a predetermined, adjustable bulk material conveying height, for example, a maximum and / or minimum bulk material conveying height, in the respective storage container, whose measuring and emission surface facing the surface of the bulk material is continuously or intermittently supplied with a measuring beam from a gas source.The adjustable gas flow under overpressure ensures that bulk material deposits remain free of deposits.

[0009] In such a device, the individual volumes of free-flowing bulk materials of various types, especially for masterbatches or similar products, can be precisely determined. This is because the sensor assigned to the respective storage container accurately determines the fill level based on the reflective surface area of ​​the bulk material being fed in. This measurement is then compared with empirically determined data, thereby controlling and regulating the feed of the bulk material. As a result, operating errors, for example during the production of masterbatches or similar products, and thus rejects, can be virtually eliminated.

[0010] The measuring and emission surface of the sensor facing the bulk material is continuously or intermittently cleaned by a pressurized gas flow, for example compressed air, to prevent measurement errors.

[0011] For highly dusty bulk materials, the material feed could also be intermittently interrupted to allow the material to settle before the measurement is carried out, although even in these cases a gas flow ensures cleaning of the sensor's measuring and emission surfaces. Furthermore, processes are conceivable in which a predetermined volume is fed into the device as a batch instead of by a blower, and the measurement is then performed to determine the respective volume or the respective bulk material conveying height within the device. Thus, various processes are possible, all of which can be advantageously used with the device according to the invention.

[0012] A time-of-flight sensor can be advantageously used to control or regulate the fill level in storage containers for bulk materials such as plastic granules, additives, color components for masterbatches, regenerates or virgin materials, PVC dry blends, powders, in color change devices, dosing systems, volumetric or gravimetric mixing systems, with one or more storage containers, for the bulk material fed to a motor-driven screw conveyor, wherein the sensor, designed as a laser sensor, within predefined limits depending on the bulk material to be conveyed, transmits the fill level and thus the volume, for example a maximum or minimum fill level, in the respective storage container as a signal to a central control or regulating device, whereby a comparison of the transmitted data with the data stored in a central data storage for the individual bulk materials to be conveyed takes place.

[0013] By means of a device according to the invention for the metered feeding of free-flowing bulk materials consisting of plastic granules, additives, color components for masterbatches, regenerates or virgin materials, PVC dry blends, powders, in color change devices, metering systems, volumetric or gravimetric mixing systems, in which, depending on the bulk material to be conveyed, the maximum and minimum volumes and / or maximum and / or minimum filling height to be maintained in the individual storage container(s) are stored in a data storage device and the data supplied by a laser sensor arranged in the interior of the respective storage container to a central control and regulation device are compared with the files stored in the data storage device for the various bulk materials and the inflow of bulk material into the respective storage container is controlled within the specified tolerances and limits and, if necessary,The procedure can be carried out without problems if the speed of the drive motor for a screw conveyor assigned to the relevant storage container is regulated or controlled.

[0014] The beam angle of the laser sensor located inside can be adjusted by the central control or regulating device in relation to the surface of the bulk material in the relevant storage container. FURTHER INVENTIVE DESIGNS

[0015] Further inventive embodiments are described in claims 2 to 5.

[0016] Claim 2 describes a device in which the sensor's angular position is adjustable depending on the reflective surface of the bulk material in the storage container. This makes it possible to determine precise data within the associated storage container, depending on the bulk material and its reflective surface, so that the sensor's reflective surface for the measuring beam can be precisely adjusted. This can be determined depending on the type of bulk material.

[0017] Claim 3 describes a device in which the sensor is a time-of-flight sensor based on FlightSense technology. Such sensors guarantee high measurement accuracy within a storage container.

[0018] According to claim 4, the sensor, located outside the storage container, can be adjusted either on the container itself or remotely with respect to its beam angle relative to the reflective surface of the bulk material inside. This eliminates the need to constantly open and clean the storage container when feeding different or changing bulk materials. Instead, depending on the type of bulk material being fed, the sensor's beam angle can be adjusted based on stored data, and the measured values ​​can be compared with a central data storage system to precisely determine the control or regulation of the fed bulk material or different bulk materials.

[0019] An advantageous embodiment is described in claim 5, in which the sensor is arranged inside the storage container. SOLUTION CONCERNING THE CONTROL OR REGULATION

[0020] Claim 6 describes the control or regulation of the volumes and / or filling height with free-flowing bulk materials such as plastic granules, additives, color components for masterbatches, regenerates or virgin materials, PVC dry blends, powders, in color-changing devices, dosing systems, volumetric or gravimetric mixing systems, for a metered feeding device as described in claim 1, with one or more storage containers for the bulk material fed to a motor-driven screw conveyor, with a sensor that is adjustable and calibratable at a predetermined, adjustable bulk material conveying height, for example, a maximum or minimum bulk material conveying height, in the respective storage container, the measuring and emission surface of which, facing the surface of the bulk material, is designed for a measuring beam, continuously or intermittently emits a laser beam from a gas source.The system is designed to prevent deposits from forming under pressure and adjustable gas flow from bulk material deposits, such that the data for the pressure of the gas flow entering the storage container and striking the sensor's emission surface, and / or its volume per unit of time, and / or the angular position of the sensor's emission surface, and / or a maximum and minimum bulk material fill level in the storage container for the various bulk materials to be conveyed, in particular plastic granules and paints, are stored in a central control or regulation unit and can be retrieved for the respective bulk material to be conveyed.

[0021] A control or regulation system according to claim 7 is particularly advantageous.

[0022] The control system according to claim 8 is characterized in that an acoustic or optical signal is triggered when the maximum fill level is exceeded and / or when the minimum fill level in the storage container is undershot. This is intended to prevent operating errors, although it is readily possible to automate the control or regulation.

[0023] Claim 9 characterizes a control or regulation system in that the supply of bulk material to the storage container is regulated or controlled within specified tolerances depending on data stored in a central data storage unit of a central control or regulation unit. SOLUTION TO THE TASK CONCERNING THE SENSOR

[0024] Claim 10 describes a sensor for such a device for the metered delivery of free-flowing bulk materials. This sensor is protected by a shielding plate.

[0025] Claim 11 describes a preferred embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0026] The drawing illustrates the invention – partly schematically – using an exemplary embodiment:

[0027] The drawing shows a dosing device for free-flowing bulk materials, in this case for plastic granules, designated overall by reference numeral 1, such as those used for color-changing devices or dosing systems with weighing or storage hoppers.

[0028] A dosing device 1 is associated with a storage container 2, which serves to hold the bulk material, for example, plastic granules, additives, or color components. The bulk material (not shown) is fed continuously or intermittently to the storage container 2 by a feeding device 3. The feeding device 3, in turn, obtains the bulk material from a silo (not shown), from which the bulk material is fed by a suitable conveying device or can also be fed manually to the feeding device 3.

[0029] The bulk material arranged in the storage container 2 enters a chamber 4 under the influence of gravity. In the illustrated embodiment, this chamber is penetrated by a screw conveyor 5, which conveys the bulk material in the direction X. The screw conveyor 5 is driven by an electric motor 6, the speed of which may be adjustable, and which is connected to an electrical network (not shown).

[0030] Reference numeral 7 designates a viewing hatch to allow access to the interior of storage container 2.

[0031] The maximum filling height is schematically indicated by reference numeral 8 and the minimum filling height of the bulk material by reference numeral 9.

[0032] The maximum filling level 8 is set by software in a data storage device as 100% fill level and stored in the system.

[0033] The minimum filling level 9 is also set by software as 0% fill level and stored in a data storage device of the system.

[0034] Both filling heights 8 and 9 can be empirically determined for the respective free-flowing bulk material to be processed and set in the data storage.

[0035] Inside the storage container 2, specifically on the inner wall of the upper material wall of the storage container 2, a sensor 10, for example a TOF sensor, is arranged. This sensor is angularly adjustable by a limited amount via a mounting bracket (not shown in detail), so that its measuring beams, schematically designated by reference numeral 11 in the drawing, strike the respective surface of the bulk material arranged in the storage container 2. The respective beam angle of the laser beam can also be stored in a data memory, specific to the material.

[0036] The sensor 10 is protected against flying material pallets by a shielding plate (not shown in detail). Furthermore, during a refilling process, for example, during the automatic filling of the storage container 2, the sensor 10 is kept clean, especially when there is a high dust content, by a pressurized gas jet 12. The gas can be compressed air, which is supplied via a line 13 from a gas source 14, for example, a gas cylinder or a gas container, to which a compressor (not shown) continuously supplies compressed air. This compressed air is supplied to the sensor and its measuring surface 15 in a controlled, intermittent, or continuous manner.

[0037] The height measurements taken by sensor 10 are continuously transmitted via a signal line 17 to a central control unit 16, which also contains a data storage device for various free-flowing bulk materials to be conveyed. The control unit 16 can also regulate or control the feed device 3 via a line 18 to determine the material flow to the storage container 2. Furthermore, the control unit 16 can regulate or control the drive motor 6 (designed as an electric motor) and thus the speed of the screw conveyor 5 via a line 19 to determine the flow of the bulk material. The numerical or graphical display of the fill levels in the storage container 2 on the central control unit 16 facilitates monitoring of the storage container 2. Standard software implementations for sensor 10, which is designed, for example, as a TOF sensor, are available as open-source code.Custom modifications to the invention can be easily implemented for practical use.

[0038] Since bulk materials differ greatly in color and thus in reflection for the measuring beam 11 and in grain size, for example from 1 mm to 10 mm, the correct angle setting of the measuring beam 11 by the adjustment option according to the invention is advantageous.

[0039] The storage container 2 can, for example, have a volume of approximately 5 liters. It can also be advantageous if the operator receives a confirmation signal at the central control unit 16 when the maximum and / or minimum fill level is reached.

[0040] The adjustment for the different fill levels in storage container 2 can be carried out in three steps:

[0041] First step: The entire container is “empty” and this is confirmed via a software button on the central control or regulation unit 16.

[0042] Second step: The operator fills the container to the minimum filling level 9 and confirms it at the central control or regulating unit 16.

[0043] Third step: The operator fills the container to the maximum filling level 8 and also confirms this at the central control and regulation unit 16.

[0044] An alarm is then triggered if the minimum filling level of 9 is undershot or if automatic refilling occurs via a suction conveyor or similar device.

[0045] The refilling stops when the maximum filling height 8 is reached, depending on the data stored in the central control or regulation unit 16 for the bulk material in question.

[0046] The features described in the claims and in the description, as well as those shown in the drawing, can be essential for the realization of the invention, both individually and in any combination. REFERENCE MARK 1 dosing device 2 storage containers 3 Feeding device 4 rooms 5 auger 6 Electric motor, drive motor 7 Viewing panel 8 Filling height, maximum 9 Filling height, minimum 10 Sensor, TOF sensor 11 Measuring beam 12 Gas jet, gas flow 13 Management 14 Gas source 15 Measuring surface 16 Control or regulating unit, central 17 Signal line 18 Management 19 Management X Direction of flow

Claims

[1] Device for metered feeding of free-flowing bulk materials such as plastic granules, additives, color components for masterbatches, regenerates or virgin materials, PVC dry blends, powders, in color change devices, dosing systems, volumetric or gravimetric mixing systems, with one or more storage containers (2), for which the bulk material is fed to a motor-driven conveying device, for example a motor-driven screw conveyor (5), with a sensor (10) assigned to the associated storage container (2), which is adjustable and calibratable at a predetermined, adjustable bulk material filling height designed as a bulk material conveying height, for example a maximum and / or minimum bulk material conveying height (8, 9), in the respective storage container (2),whose measuring and emission surface (15) facing the surface of the bulk material is continuously or intermittently free of deposits from bulk material deposits by a measuring jet (11) supplied by a gas source (14) under overpressure and adjustable gas flow. [2] Device according to claim 1, characterized by , that the sensor (10) is adjustable in its angular position depending on the reflective surface of the bulk material located in the storage container (2). [3] Device according to claim 1 or 2, characterized by , that the sensor (10) is a time-of-flight sensor based on FlightSense technology. [4] Device according to claim 1 or any of the following claims, characterized by, that the sensor (10) outside the storage container (2) is adjustable either on the container itself or by remote control with regard to its beam angle in relation to the reflective surface of the bulk material located in the storage container (2). [5] Device according to claim 1 or any of the following claims, characterized by , that the sensor (10) is located inside the storage container (2), on its inner wall facing the screw conveyor, below a feed device (3) for the bulk material. [6] Control or regulation of the volumes and / or filling height with free-flowing bulk materials such as plastic granules, additives, color components for masterbatches, regenerates or virgin materials, PVC dry blends, powders, in color change devices, dosing systems, volumetric or gravimetric mixing systems, with one or more storage containers (2) for the bulk material fed to a motor-driven screw conveyor (3), with a sensor (10) which is adjustable and calibratable at a predetermined, adjustable bulk material conveying height, for example a maximum or minimum bulk material conveying height (8, 9), in the relevant storage container (2), the measuring and emission surface of which, facing the surface of the bulk material, is designed for a laser beam (11) continuously or intermittently supplied by an adjustable gas flow under overpressure from a gas source (14) and is free of deposits from bulk material deposits,such that the data for the pressure of the gas flow (12) entering the storage container (2) and striking the emission surface of the sensor (10) and / or its volume per unit of time and / or the angular position of the emission surface of the sensor (10) and / or a maximum and minimum bulk material filling height in the storage container (2) for the various bulk materials to be conveyed, in particular plastic granules and paints, are stored in a central control or regulating unit (16) and can be retrieved for the respective bulk material to be conveyed. [7] Control or regulation according to claim 6, characterized by, that depending on the material to be conveyed, the respective bulk material conveying height, for example a maximum and / or minimum bulk material conveying height, is stored in a material-specific data storage in the storage container (2) and the control or regulation for conveying bulk material into the storage container (2) and / or the speed of the drive motor (6) of the screw conveyor (5) are controllable or adjustable. [8] Control according to claim 6 or 7, characterized by , that when the maximum filling level is exceeded and / or when the minimum filling level in the storage container is not reached, an acoustic or optical signal (10) is triggered. [9] Control according to claim 6 or 7, characterized by, that the supply of bulk material into the storage container (2) is regulated or controlled within specified tolerances depending on data stored in a central data storage unit of a central control or regulation unit (2). [10] Sensor for a device according to claim 1 or any of the following claims, in the form of a Toft sensor, characterized by , that the sensor (10) is associated with a shielding plate which protects the emitting surface from direct contact with bulk material. [11] Sensor according to claim 10, characterized by, that the sensor (10) is arranged as a replaceable unit on the underside of the upper wall of the storage container (2) and on its inside via a holding device which enables an angular adjustment of the sensor (10) within specified angular tolerances with respect to the surface of the bulk material to be detected in the storage container (2) in question.

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