Device for discharging poorly flowing goods from a storage container

Abstract

Device for discharging poorly flowing goods from a storage container, wherein the device has only one continuous shaft on which two discharge screws are at least partially arranged, wherein the discharge screws (5, 6) each have an internal thread and the shaft (4) each have two corresponding external threads, such that the discharge screws (5, 6) can be slid onto the shaft (4) and secured via the thread, characterized in that a trapezoidal thread is provided, and that screw wings (23, 24) of the discharge screws (5, 6) have loosening rippling teeth (35).

Description

[0001] The invention relates to a device for discharging difficult-flowing goods from a storage container, in particular a silo.

[0002] State-of-the-art devices for discharging slow-flowing materials from a silo include two discharge screws arranged diametrically opposite one another along a vertical axis of the device. Since such discharge screws are typically very long, for example, five to twelve meters, state-of-the-art discharge screws feature a holding device that supports each end of the discharge screws. These holding devices are arranged laterally next to the discharge screws. This state-of-the-art device has the disadvantage of being very complex in design. Furthermore, the material to be discharged can become stuck between the discharge screw and the holding device, frequently requiring additional maintenance.

[0003] State-of-the-art devices include a drive mechanism. This drive mechanism sets the discharge screws in rotation, causing them to rotate around their longitudinal axes. Furthermore, the device itself rotates around its own longitudinal axis, which is aligned approximately perpendicular to the longitudinal axis of the screws, causing the discharge screws to rotate in the bottom area of ​​the silo. Due to this rotation, the screws cover almost the entire bottom area of ​​the silo.

[0004] The screws and the device have a total length that almost corresponds to the diameter of the silo.

[0005] The rotation of the screws around their longitudinal axis conveys the material to be discharged to the center of the silo. Furthermore, the state of the art includes

[0006] (DE 102 61 395 A1) Devices with a silo removal auger designed as a single-arm auger. The device is designed such that it rotates 360° once to cover the entire area of ​​the silo floor.

[0007] This state-of-the-art device features solid-material augers. This means the auger shaft is made of solid material and is supported on one side of the device without any additional support structures. In this state-of-the-art silo removal auger, the shaft is supported within the device by two or more bearings, such that the shaft extends beyond the bearing spacing to ensure a cantilevered bearing outside the device.

[0008] However, with this device it is necessary that the device rotates 360° to travel over the entire silo floor area. In addition, the state of the art includes

[0009] (DE 43 35 949 A1) a device for ejecting material from a silo. This device has one or more ejection screws. In this device, the drive system consists of a single drive and a connected transmission device that rotates the ejection screws about their own axis and the ejection screws about the longitudinal axis of the silo. A bevel gear is used as the transmission. Due to the large static and dynamic forces, particularly frictional and compressive forces, that the bulk material exerts on all internal components in a silo during filling and discharge, both the bearings for the longitudinal axis and the longitudinal axis itself are extremely vulnerable. Furthermore, strong moments act on the horizontally arranged screw ejectors, which are not supported at the ends. The continuous axis is also a hindrance in many cases.

[0010] Furthermore, the state of the art (DE 518 483 A) includes a conveyor screw with replaceable blades. Fixed blades are mounted on a screw shaft, and replaceable end blades are mounted on a hub (4). These are held in place by a sleeve and an adjusting ring, which can be slid onto the tapered extension of the screw shaft.

[0011] This state-of-the-art screw conveyor has the disadvantage of being very complex in design, as one part of the screw has fixed blades, while another part is pushed onto it with end blades. This requires the blade transitions to be designed very precisely to avoid undesirable transverse forces that occur when discharging the material.

[0012] The state of the art (DD 35 556 A1) includes a metering bunker discharge device featuring a screw shaft with left and right-hand screw flights. This state-of-the-art device has the disadvantage of being complex and difficult to maintain, as it features a continuous shaft on which the screw flights are directly arranged. This continuous shaft is extremely cumbersome for repair work. Furthermore, the state of the art includes

[0013] (US 3,180,525 A) a screw shaft in which two discharge screws are arranged on one shaft. These discharge screws are attached to the shaft by means of a nut. The discharge screws are subject to considerable forces, as the threads of the discharge screws must work against the material being discharged. These considerable forces are absorbed only by the relatively small nuts. In addition, the state of the art includes

[0014] (DE 23 50 812 C3) a silo for storing bulk materials. The silo features a discharge device in the form of a horizontal screw conveyor at the bottom of the silo housing. This continuous discharge screw is also extremely cumbersome to handle during repair work. Furthermore, the state of the art includes

[0015] (DE 196 00 858 A1) describes a discharge device for slow-flowing bulk materials, but it does not have an axis on which screws are mounted. Furthermore, it features a discontinuous shaft. The state of the art also includes

[0016] HABENHAUER, Horst; BODENSTEIN, Ferdinand: Machine Elements - Design, Calculation, Application. 13th updated edition. Berlin: Springer, 2005 (Springer Textbook). pp. 167-212. - ISBN 3-540-22284-7. According to this textbook, basic types of threads are listed. A device for discharging slow-flowing materials from a storage container using a trapezoidal thread is not disclosed in this publication.

[0017] The technical problem underlying the invention is to provide a device for discharging difficult-to-flow goods from a storage container, which device is designed as a double-arm screw and in which, moreover, holding devices in addition to the discharge screws can be dispensed with.

[0018] This technical problem is solved by the device having the features according to claim 1.

[0019] The device according to the invention for discharging difficult-to-flow goods from a storage container, which has only one continuous axis on which two discharge screws are at least partially arranged, in which the discharge screws each have an internal thread and the axis has two corresponding external threads, such that the discharge screws can be pushed onto the axis and secured via the thread, is characterized in that a trapezoidal thread is provided and that screw flights of the discharge screws have loosening ripper teeth.

[0020] According to a particularly preferred embodiment of the invention, the device has only one axis on which two discharge screws are arranged.

[0021] The invention relates to a device for discharging slow-flowing materials from a storage container, such as a silo. However, the invention is not limited to a silo, but rather applies to any type of storage container. The invention is described below in its application to a silo, but is not limited to this application.

[0022] According to the particularly preferred embodiment, the device comprises only one continuous axis, on which two discharge screws are arranged at least partially on both sides. For this purpose, the discharge screws at least partially comprise a hollow shaft. According to a preferred embodiment, the shaft of the discharge screws is designed entirely as a hollow shaft.

[0023] The axis is advantageously mounted at least approximately centrally in the device, i.e. the axis protrudes from the device at the same distance on both sides of the device.

[0024] Advantageously, the axis is designed to be drivable in order to rotate the discharge screws arranged on the axis.

[0025] It is also possible to design the discharge screws arranged on the axle so that they can be driven. This allows the axle to be mounted on a rotatable base and the discharge screws to be driven so that the axle rotates with it. However, it is also possible to mount the discharge screws on the axle so that they can rotate. Structurally, however, the simplest solution is for the axle itself to be mounted on a rotatable base, and for the discharge screws to be fixed but detachably mounted on the axle.

[0026] According to a particularly preferred embodiment of the invention, the axle in the device is mounted with at least two bearings to support the weight of the axle with the discharge screws. According to a particularly preferred embodiment, the axle is formed at least partially from solid material. Particularly advantageously, the entire axle is formed from solid material in order to support the heavy weight of the discharge screws arranged on the axle.

[0027] The discharge screw shaft is advantageously at least partially hollow so that the discharge screws can be arranged on the axis. The discharge screw shaft must be hollow in the area where the axis is located. To achieve material and weight savings, the discharge screw shaft can also be completely hollow.

[0028] According to an advantageous embodiment of the invention, the axis has a length which corresponds approximately to half the diameter of the silo.

[0029] The axle should preferably have a minimum length of approximately one-quarter the diameter of the silo. This ensures that the axle can support the weight of the discharge screws arranged on it.

[0030] In principle, however, it is also possible for the axle to have a length that almost corresponds to the diameter of the silo. For maintenance and repair work, however, it is advantageous if the axle is shorter and the discharge screws are pushed onto the axle, as this allows maintenance and adjustment work without having to remove the entire device from the silo. In this case, the discharge screws can be pulled off the axle, providing easy access to the device, for example, to the device's bearings and the drive.

[0031] According to the invention, the screw flights of the discharge screws are equipped with loosening teeth. Since the material to be discharged is a difficult-to-flow material, such as wood shavings, sawdust, chopped bark, waste wood, animal meal, flux, and veneer waste, loosening teeth are sometimes necessary to loosen the material so that it can be conveyed by the screws to the center of the silo.

[0032] Advantageously, at least one conical drive is provided for driving the axle and / or the discharge screws.

[0033] According to a particularly preferred embodiment of the invention, only one conical drive is provided for driving the axle with the two discharge screws. If only one drive is provided, the two discharge screws must have counter-rotating screw flights, since the discharge screws have a common direction of rotation. To ensure that the material is conveyed to the center of the silo, the screw flights must be counter-rotating.

[0034] According to an advantageous embodiment of the invention, the discharge screws are detachably attached to the axle so that they can be removed from the axle for maintenance work.

[0035] According to a preferred embodiment of the invention, the discharge screws each have an internal thread and the axle has two corresponding external threads, so that the discharge screws can be pushed onto the axle and secured via the thread.

[0036] For example, it is possible to provide a trapezoidal thread, as this is relatively robust against jamming.

[0037] Advantageously, the device has adjustable and readjustable bearings to simplify assembly and maintenance work.

[0038] Further features and advantages of the invention will become apparent from the accompanying drawing, the sole figure of which shows the structure of a device according to the invention for discharging slow-flowing goods from a silo only by way of example.

[0039] The figure shows a device 1 arranged in a silo 2. The device 1 consists of a drive unit 3 and discharge screws 5, 6 arranged on an axis 4. The discharge screws 5, 6 are hollow so that they can be arranged on the axis 4.

[0040] The difficult-to-flow material (not shown) arranged in the silo is conveyed by the discharge screws 5, 6 in the direction of the arrows A. The material is introduced through openings 7, 8 of the device 1 into a chamber 9 of the device 1 and leaves the device 1 and thus the silo 2 via one or more schematically indicated and not shown discharge openings 10.

[0041] The device 1 has a dome 11 so that the material advancing from above due to gravity is guided onto the discharge screws 5, 6.

[0042] Axle 4 and thus the discharge screws 5, 6 arranged on axis 4 are driven by a bevel drive. The bevel drive has a bevel gear 12 and an axis 14 driven by a motor 13. Additionally, a chain coupling 15 with a double roller chain and seals 16 are provided. The axis 14 is rotatably mounted in bearings 17.

[0043] To ensure that the material to be conveyed enters chamber 9 and is kept away from the chamber 18, which accommodates the bevel gear 12 and is surrounded by a housing 19, a conical guide plate 20 is provided on each side of the axle 4. Seals 22 are provided for sealing.

[0044] The discharge screws 5, 6 have screw blades 23, 24. Since the axis 4 and thus the discharge screws 5, 6 rotate in one direction around a longitudinal axis 25, the screw blades 23, 24 are designed to rotate in opposite directions.

[0045] The entire device 1 is additionally rotated around its longitudinal axis 26 in the direction of arrow B so that the discharge screws 5, 6 cover the entire base area of ​​the silo 2. The drive required for this is known from the prior art and, for reasons of clarity, is not shown or explained in detail here. For this purpose, the device 1 has a gear ring arranged on the outside of the device 1, via which the part of the device 1 carrying the axis 4 and the discharge screws 5, 6 is rotated.

[0046] The figure also shows planetary gears 27 and a cross roller slewing ring 28.

[0047] The assembly of device 1 is carried out as follows: - The axis 4 is inserted from the outside until the bevel gear 12 including a key (not shown) can be placed on it. - Ring nuts 29, 30, 31 are screwed to the approximate position. - Roller bearings 32 are then installed. - Bearing caps 21, 33 are fitted with seals and screwed on. - Then, the axle 4 is secured. Using the ring nut 31, the axle 4 is lightly pressed against the bearing cover 21 and secured. - Next, the bevel gear backlash is adjusted. To do this, the threaded rings 29 and 30 are adjusted until the desired backlash is achieved. The threaded rings 29 and 30 are then secured. - The discharge screw 5 is pushed onto the shaft 4 into the desired position and rotated onto a shaft thread 33 until driver grooves 34 allow the insertion of a driver (not shown). - The driver is installed. - The discharge screw 6 is installed according to the same principle as the discharge screw.

[0048] The device 1 according to the invention is characterized in that a continuous axis 4 is provided for carrying the two discharge screws 5, 6.

[0049] The way in which the flank clearance of the bevel gears 12 is adjusted by means of the ring nuts 29, 30, 31 is advantageous because it is particularly simple.

[0050] Another advantage is the inclusion and drive of the hollow-shaft discharge screws 5, 6. These can be removed without removing the discharge mechanism when they become worn. To do so, simply unscrew the driver from the drive groove 34 of the shaft 4, and the discharge screws 5, 6 can be easily replaced.

[0051] The screw flights 23, 24 of the discharge screws 5, 6 have loosening ripper teeth 35 in order to loosen the material to be discharged and to be able to convey it better, since it is a material that is difficult to flow.

[0052] The auger blades 23, 24 are shown as examples only. Advantageously, the auger blades 23, 24 carry the auger blades 35 evenly distributed over their entire circumference.

[0053] The device according to the invention is characterized in that the device 1 has only one axis 4 on which the two discharge screws 5, 6 are arranged. Reference numbers 1 device 2 silos 3 Drive unit 4 axis 5 discharge screw 6 discharge screw 7 Opening 8 Opening 9 Room 10 Surgical opening 11 Cathedral 12 bevel gear 13 Engine 14 Axis 15 Chain coupling 16 seals 17 camps 18 Room 19 housings 20 conical sheet 21 bearing cap 22 seals 23 snail wings 24 snail wings 25 Longitudinal axis 26 Longitudinal axis 27 planetary gears 28 Cross roller slewing ring 29 Ring nut 30 ring nut 31 ring nut 32 roller bearings 33 shaft threads 34 drive grooves 35 loosening fangs A Arrow B Arrow

Claims

[1] Device for discharging difficult-to-flow goods from a storage container, in which the device has only one continuous axis on which two discharge screws are at least partially arranged, in which the discharge screws (5, 6) each have an internal thread and the axis (4) each have two corresponding external threads, such that the discharge screws (5, 6) can be pushed onto the axis (4) and secured via the thread, characterized by that a trapezoidal thread is provided, and that screw flights (23, 24) of the discharge screws (5, 6) have loosening teeth (35). [2] Device according to claim 1, characterized by that the axis (4) is mounted at least approximately centrally in the device (1). [3] Device according to claim 1 or 2, characterized by that the axis (4) is designed to be drivable. [4] Device according to claim 1, characterized bythat the discharge screws (5, 6) arranged on the axis (4) are designed to be drivable. [5] Device according to claim 1, characterized by that the axis (4) is mounted in the device (1) with at least two bearings (32). [6] Device according to claim 1, characterized by that the device (1) is designed to be rotatable. [7] Device according to one of the preceding claims, characterized by that the axis (4) is at least partially made of solid material. [8] Device according to one of the preceding claims, characterized by that a shaft of the discharge screws (5, 6) is at least partially hollow. [9] Device according to one of the preceding claims, characterized by that the axis (4) has a length which corresponds approximately to half the diameter of the silo (2). [10] Device according to one of the preceding claims, characterized bythat the axis (4) has a minimum length corresponding to approximately a quarter of the diameter of the silo (2). [11] Device according to one of the preceding claims, characterized by that the axis (4) and / or the discharge screws (5, 6) are driven by at least one conical drive (12, 13, 14). [12] Device according to one of the preceding claims, characterized by that only one conical drive (12) is provided for driving the axis (4) with the two discharge screws (5, 6). [13] Device according to claim 12, characterized by that the two discharge screws (5, 6) have counter-rotating screw flights (23, 24). [14] Device according to one of the preceding claims, characterized by that the discharge screws (5, 6) are designed to be detachably attachable to the axis (4). [15] Device according to claim 14, characterized bythat the discharge screws (5, 6) each have an internal thread and the axis has two corresponding external threads (33). [16] Device according to one of the preceding claims, characterized by that the device (1) has adjustable and adjustable bearings.

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