Metering device

Abstract

The invention relates to a metering device (1) for continuous gravimetric metering of pourable material, in particular coarse fuel, in which a material flow is conveyed from a charging opening to an emptying opening in a housing having a rotor (3) which is driven about a vertical axis of rotation while determining the instantaneous load on a measuring part, and having a force measuring device for measuring the instantaneous load on the measuring part. The force measuring device detects an instantaneous load of the material flow guided through the rotor. The rotor (3) comprises a plurality of ribs (11) and a peripheral ring (14) attached thereto and defining a plurality of chambers (64) inside the peripheral ring for transporting material during operation wherein a peripheral sealing lip (60) is arranged on the peripheral ring and engages the upper housing wall (22) such that the outer peripheral volume inside the housing is sealed with respect to the central volume of the housing.

Description

[0001] This application is a divisional application of patent application No. 201880045419.5 (PCT / EP2018 / 068216) entitled “Measuring Device” filed by the applicant on July 5, 2018. Technical Field

[0002] A metering device for continuous gravimetric metering of pourable material, in particular raw meal for cement production, wherein a material flow is conveyed in a housing from a charging opening to an emptying opening, having a rotor which is driven about a vertical axis of rotation while determining the instantaneous load on a measuring portion, and having a force measuring device which detects the instantaneous load of the material flow guided through the rotor, the rotor comprising a plurality of ribs and a peripheral ring, the ribs being attached to the peripheral ring and defining a plurality of chambers inside the peripheral ring for conveying material during operation, wherein an elastic peripheral sealing lip is arranged on the peripheral ring and engages the upper housing wall, thereby sealing an outer peripheral volume inside the housing relative to a central volume of the housing.

[0003] The invention relates to a metering device for the continuous gravimetric metering of pourable materials. Background Art

[0004] Such a metering device is known, for example, from U.S. Pat. No. 4,528,848, which discloses a device for continuous weight metering of pourable material, the material being delivered through a charging port into a pocket of a rotor arranged in a housing rotatable about a substantially vertical axis, and being delivered from the pocket through a discharge port, the discharge port being arranged to be offset relative to the charging port in the direction of rotation of the rotor. The housing is pivotally mounted in a frame about a substantially horizontal axis and is suspended from the frame by a dynamometer arranged away from the axis. Typically, with known systems, such raw material for cement production is supplied from a storage tank to a heat exchanger in large quantities of 30 to 1000 tons per hour. For this purpose, the material is guided to a belt metering device through a conveying trough. The conveying trough is arranged in an inclined position and is provided with a porous bottom, allowing air to be finely distributed from a compressed air space into the material conveyed on the conveying trough. However, such a system operates as an open system, requiring considerable measures as a cover and a housing to comply with environmental regulations. Summary of the invention

[0005] The object of the present invention is to provide an improved metering device of the above-mentioned type. This object is solved by a metering device.

[0006] By arranging the elastic sealing lip on the peripheral ring and engaging the upper housing wall, a safe, wear-resistant and non-blocking feed is achieved. In addition, the lip can be arranged so that it increases the sealing pressure due to the pressure of the material from the inside of the rotor.

[0007] Furthermore, the lip may be arranged on the peripheral ring at an angle from the outer ring and towards the central portion of the rotor so that material inside the rotor will apply sealing pressure to the lip during operation by pressing the lip against the upper housing wall above the rotor. By angling the lip inwardly towards the centre of the metering device, the pressure exerted on the lip by material flowing inside the metering device will improve the seal in accordance with the increased pressure inside the device as the material will push the lip towards the upper housing wall, thereby improving the sealing effect.

[0008] The lip may advantageously comprise an L-shaped cross section, since when mounted directly on a vertical surface of the peripheral ring, an angle towards the centre can then be easily achieved by the profile of the lip.

[0009] In order to increase the capacity of the metering device, at least one rib sealing lip may further be arranged on one or more ribs for preventing material from flowing over the ribs between adjacent spaces and allowing a space to be filled completely without overflowing into adjacent spaces.

[0010] Likewise, at least one additional rib sealing lip may be arranged on one or more ribs, so that the rib sealing lip and the additional rib sealing lip are arranged in a double-lip configuration on one or more ribs.

[0011] The objects of the invention are also achieved by a metering device for continuous weight metering of pourable material, in particular raw meal for cement production, wherein a material flow can be conveyed in a housing from a charging opening to an emptying opening, having a rotor which is driven about a vertical axis of rotation while determining the instantaneous load on the measuring part, and having a force measuring device which can detect the instantaneous load of the material flow guided through the rotor, the rotor comprising a plurality of ribs which define a plurality of chambers for conveying material during operation, characterized in that at least one rib sealing lip can be arranged on one or more ribs for preventing material from flowing over the ribs between adjacent chambers.

[0012] At least one rib sealing lip may be arranged on the rib at an angle to the rib and opposite to the direction of rotation of the rotor. At least one rib sealing lip may have an L-shaped cross-section and / or may be elastic. In some embodiments, at least one additional rib sealing lip may be arranged on one or more ribs (for preventing material from flowing through the ribs between adjacent chambers). In some embodiments, at least one additional rib sealing lip may be arranged on the rib at an angle to the rib and opposite to the direction of rotation of the rotor. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In the following, exemplary embodiments will be explained and described in more detail based on the accompanying drawings, in which:

[0014] Figure 1 is a side elevation view of the metering device;

[0015] Figure 2is a first side view of the metering device rotated 90°;

[0016] Figure 3 is a second side view of the metering device rotated 90°;

[0017] Figure 4 is a cross-sectional view of the rotor;

[0018] Figure 5 is a perspective view of the rotor;

[0019] Figure 6 is an enlarged perspective view of the rotor;

[0020] Figure 7 is an enlarged perspective view of the rotor. DETAILED DESCRIPTION

[0021] Figure 1 , 2 3 show a metering device 1 from different angles, which basically comprises a metering rotor 3 rotating in a housing 4, which is completely closed except for a charging opening 5 and an emptying opening 7. In this case, the charging opening 5 and the emptying opening 7 are arranged with respect to each other to form a measuring section that is as long as possible. As described below, the housing 4 is rotatably mounted in the frame 2. Two pivot bearings 18 are provided to form a pivot axis about which the housing 4 can be pivoted when loaded with material. Seen from above, this pivot axis a extends through the center of the top charging opening 5 and the bottom emptying opening 7 to eliminate the influence of errors caused by the supply and discharge of goods, respectively.

[0022] A drive device 9 is provided to drive the rotor 3 of the metering device 1, which drive device 9 is formed, for example, by an electric motor (not described in detail) and a bevel gear, the exit of which leads to a vertical shaft 25 (see FIG. Figure 3 ). In this case, the drive device 9 is mounted directly to the housing 4 so that it is adapted to follow any rotational movement about the above-mentioned pivot axis 8. During a rotational movement about the pivot axis 8, such as caused by the supply and feed of material along the measuring section 2, the housing 4 is supported on a force measuring device 10 which is fixedly arranged in the frame 2 and is connected to the housing 4, for example, by a tie rod.

[0023] Different kinds of dynamometers can be used to represent the force measuring device 10, however directly operated sensors are used, such as strain gauges, shear force sensors, etc. In doing so, the corresponding mass of the material flow conveyed along the measuring section is detected, and the product of the instantaneous load and the conveying speed is detected to determine the flow rate. The drive device 9 and therefore the rotational speed of the rotor 3 are readjusted by means of a control device known per se and not shown in greater detail, in order to change the flow rate or to set a predetermined amount.

[0024] from Figure 5 It can be clearly seen that the height of the radially extending entrainment ribs 11 of the rotor 3 reaches the inner height of the housing 4. For feeding, the tube 12 passes through the upper housing wall 22 of the housing 4. The radially arranged entrainment ribs 11 of the rotor 3 are connected to each other via the peripheral ring 14, which leads to a high stability of the rotor 3. In addition, it is the effect of the peripheral ring 14 extending almost to the upper housing wall 22 that prevents the bulk material fed through the charging opening 5 in the hopper 12 from drifting outwards.

[0025] As mentioned earlier, Figure 3 The metering device 1 is shown in a side view, in which in particular the path of the pivot axis 8 formed by the pivot bearing 18 can be seen. In addition, the structure of the housing 4 is shown, which has a housing shell, an upper housing wall 22 and a lower housing wall 24 connected to the upper housing wall 22, for example by a screw connection 21. Figure 1 The force measuring device 10 shown in FIG. 4 is arranged at the circumference of the housing 4 in order to achieve the greatest possible effective lever length, however, it can also be mounted further away or closer to the pivot axis 8 .

[0026] exist Figure 4 , an enlarged view of the rotor 3 shows the sealing lip 60 disposed on the peripheral ring 14 engaging the upper housing wall 22. The lip 60 can be attached to the ring 14 by standard bolt and nut attachments 63. Importantly, the lip 60 is disposed at an angle toward the center of the rotor 3 so that pressure from material inside the rotor 3 helps to increase the sealing pressure between the lip 60 and the upper housing wall 22. Disposing the lip 60 at an angle away from the center would allow pressure from the material to deflect the lip away from the upper housing wall 22 and allow material to escape over the lip. Providing an L-shaped lip 60 and directing one leg of the L-shape toward the center of the rotor 3 and securing one leg of the L-shape to the peripheral ring 14 effectively provides an increased sealing effect.

[0027] exist Figure 5 , a perspective view of a rotor shows an embodiment of the invention in which a plurality of rib sealing lips 61 are arranged on the ribs 11. By arranging a further set of lips on the ribs 11, the capacity and efficiency of the metering device can be even further increased to the maximum possible metering volume by reaching the upper housing wall 22 and preventing material from flowing through the ribs between adjacent chambers. In order to increase the sealing effect between adjacent chambers, an additional rib sealing lip 62 can be arranged next to the rib sealing lip 61, as in the double lip arrangement. Figure 5 shown.

[0028] In some embodiments, a plurality of rib sealing lips 61 may be arranged on the rib 11 and the metering device does not include the peripheral ring 14 or the peripheral sealing lips 60. The rib sealing lips 61 may be attached to the rib 11 by standard bolt and slot nut attachments 63. The sealing lips 61 may be arranged on the rib 11 at an angle to the rib 11 and opposite to the direction of rotation of the rotor 3. Providing an L-shaped lip 61 and directing one leg of the L-shape toward the center of the rotor 3 and securing one leg of the L-shape to the rib 11 effectively provides an increased sealing effect. Figure 6 and 7 As shown, the rib sealing lip 61 may be arranged on either side of the rib 11 .

[0029] The metering device of the invention may also comprise one or more additional peripheral sealing lips for improving the seal so that the outer peripheral volume inside the housing is even better sealed to the central volume of the housing.

Claims

1. A metering device (1) for the continuous gravimetric metering of pourable material, preferably raw meal for cement production, wherein: A material flow is conveyed in a housing from a charging opening to an emptying opening, having a rotor (3) which is driven about a vertical rotation axis while determining the instantaneous load on a measuring portion, and having a force measuring device which detects the instantaneous load of the material flow guided through the rotor (3), the rotor (3) comprising a plurality of ribs (11) and a peripheral ring (14), the ribs being attached to the peripheral ring, and the ribs (11) defining a plurality of chambers inside the peripheral ring for conveying material during operation, characterized in that a peripheral sealing lip (60) is arranged on the peripheral ring (4) and engages an upper housing wall (22), thereby sealing an outer peripheral volume inside the housing relative to a central volume of the housing.

2. The metering device according to claim 1, characterized in that The peripheral sealing lip (60) is arranged on the peripheral ring (14) at an angle from the outer ring and towards the central part of the rotor (3), so that the material inside the rotor applies sealing pressure to the peripheral sealing lip (60) during operation by pressing the peripheral sealing lip (60) against the upper housing wall (22) above the rotor (3).

3. The metering device according to claim 1 or 2, characterized in that: The lip (60) has an L-shaped cross-section.

4. The metering device according to any one of claims 1 to 3, characterized in that: The peripheral sealing lip (60) is elastic.

5. The metering device according to any one of claims 1 to 4, characterized in that: At least one rib sealing lip (61) is disposed on one or more ribs (11) for preventing material from flowing past the ribs (11) between adjacent chambers (64).

6. The metering device according to any one of claims 1 to 5, characterized in that: The at least one rib sealing lip (61) is arranged on the rib (11) at an angle to the rib (11) and opposite to the direction of rotation of the rotor (3).

7. The metering device according to any one of claims 1 to 6, characterized in that: The at least one rib sealing lip (61) has an L-shaped cross section.

8. The metering device according to any one of claims 1 to 7, characterized in that: The at least one rib sealing lip (61) is elastic.

9. The metering device according to any one of claims 1 to 8, characterized in that: At least one additional rib sealing lip (62) is disposed on one or more of the ribs (11) for preventing material from flowing past the ribs (11) between adjacent chambers (64).

10. The metering device according to any one of claims 1 to 9, characterized in that: The at least one additional rib sealing lip (62) is arranged on the rib (11) at an angle to the rib (11) and opposite to the direction of rotation of the rotor (3).

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