Fixed weight feeding device

Abstract

To provide a fixed-weight feeding device that is capable of measuring minute amounts while reducing a scale of the whole feeding device.SOLUTION: A fixed-weight feeding device is divided into a feeding side A for receiving the supply of a granular material, and a measuring side B for measuring the weight with a sensor, and the feeding side A using a first rotation shaft 2, and the measuring side B using a second rotation shaft 3 are driven in parallel in reverse directions. The fixed-weigh feeding device includes: an upper side supply board 7 where the measuring side B is formed to have a smaller diameter than the feeding side A, and the measuring side B fetches the granular material from the feeding side; an upper side casing 8 having an upper side opening part 8b which slidingly contacts the upper side supply board 7 to allow the granular material to fall; a lower side supply board 9 which conveys the granular material falling from the upper side opening part 8b; a lower side casing 10 having a lower side opening part 10b which slidingly contacts the lower side supply board 9 to allow the granular material to fall; a load cell 12; and a scale table 11 which measures the weight of the granular material.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a constant weight supplying device capable of supplying a minute amount of powder or granular material. [Background technology]

[0002] Supply devices for supplying a fixed amount of powder or granular material can be broadly divided into volumetric and gravimetric types.

[0003] A volumetric pump uses multiple masses with a fixed volume that are provided on a supply platen. The supply volume is then multiplied by the volume of the masses, the number of masses provided on the supply platen, and the rotation speed or number of revolutions of the rotating shaft that supports the supply platen to make the supply volume constant. However, if the filling rate per mass becomes unstable or the density of the powder or granular material changes, the supply amount will naturally become unstable, but a volumetric pump cannot detect such changes. As a result, problems such as uneven processing may occur downstream of the supply.

[0004] For this reason, for example, as shown in Patent Document 1 (JP Patent Publication 2005-114408 A), a weight-based constant quantity supplying device has been developed and has come into practical use.

[0005] With a gravimetric type, the weight remains constant even if the filling rate or density changes, so the above-mentioned problems are unlikely to occur. However, conventional gravimetric constant-volume feeders have the problem that the entire device tends to become large, and more importantly, it is difficult to measure minute amounts. This is due to the following reasons. That is, in conventional gravimetric feeders, the diameter of the storage tank is equal to the diameter of the cylindrical part where the measurement is performed, and a single-axis configuration is adopted.

[0006] If the diameter of the storage tank is too small, cavities will form in the powder and make it difficult to discharge, so it must be set to a certain value or more, which results in poor metering accuracy. In fact, the minimum supply rate is limited to several hundred g / h. In short, it is impossible to measure minute amounts such as a few g / h.

[0007] [Patent Document 1] JP 2005-114408 A DISCLOSURE OF THEINVENTION [Problem to be solved by the invention]

[0008] In view of the above circumstances, an object of the present invention is to provide a constant weight supplying device that is capable of measuring minute amounts such as a few g / h while reducing the size of the entire supplying device. [Means for solving the problem]

[0009] The constant weight supplying device according to the first invention is divided into a supply side that receives powder or granular material and a weighing side that uses a sensor to weigh the powder or granular material, the supply side is driven by a first rotating shaft, and the weighing side is driven by a second rotating shaft that is parallel to the first rotating shaft, and the first and second rotating shafts rotate in opposite directions. The weighing side is formed with a smaller diameter than the supply side, and the weighing side intersects with the supply side to take in the powder or granular material from the supply side and is supported by an upper side journaled on the second rotating shaft. The device comprises a supply plate, an upper casing having an upper opening that is in sliding contact with the underside of the upper supply plate and allows the powdered material to fall into a portion of it, a lower supply plate located directly below the upper casing, transporting the powdered material falling from the upper opening and supported by a second rotating shaft, a lower casing having a lower opening that is in sliding contact with the underside of the lower supply plate and allows the powdered material to fall into a portion of it, and a weighing platform equipped with a sensor and used to measure the weight of the powdered material that falls from the lower opening or is transported by the lower supply plate.

[0010] In this way, this constant weight supplying device is divided into a supply side that receives powder and granular material and a weighing side that performs weight measurement using a sensor, and the supply side is driven by a first rotating shaft, and the weighing side is driven by a second rotating shaft parallel to the first rotating shaft. In other words, it has a two-shaft configuration with a first and second rotating shaft. In addition, the first and second rotating shafts rotate in opposite directions, and the weighing side is formed with a smaller diameter than the supply side.

[0011] This ensures that the size of the supply side is sufficiently large, enabling smooth discharge of powder and granular materials. The overall equipment scale can be reduced, and the weighing side can be made small. This makes it possible to weigh minute amounts such as a few g / h. Moreover, by configuring the upper supply plate, lower supply plate, and weighing platform as described above, minute amounts can be weighed without any problems. In addition, because the first and second rotating shafts rotate in opposite directions, the powder and granular materials can be smoothly exchanged between the supply side and the weighing side.

[0012] In the constant weight supply device of the second invention, in addition to the features of the first invention, the supply side is provided with an agitator that is journalled on the first rotating shaft and that breaks up the powder or granular material supplied into the supply side and transports it to the upper supply plate on the weighing side.

[0013] With this configuration, the powdered material can be smoothly transported from the supply side to the weighing side.

[0014] In the constant weight supplying device according to a third aspect of the present invention, in addition to the features of the first aspect, the upper supply platen and the lower supply platen are provided with a plurality of masses that are formed at positions that coincide in the vertical direction.

[0015] This configuration allows the relationship between the upper and lower supply boards to be easily synchronized, achieving smooth operation.

[0016] A constant weight supplying device according to a fourth aspect of the present invention is similar to that of the first aspect of the present invention, in which the sensor is a load cell.

[0017] This configuration makes it possible to introduce a highly accurate weight sensor at low cost. Effect of the Invention

[0018] According to the present invention, it is possible to realize a constant weight supplying device that is capable of measuring minute amounts such as a few g / h while reducing the overall scale of the supplying device. BEST MODE FOR CARRYING OUT THEINVENTION

[0019] (Embodiment 1) Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Fig. 1 is an overall perspective view of a constant weight supplying device in embodiment 1 of the present invention, Fig. 2 shows the device with the supply side removed, and Fig. 3 is an exploded perspective view of the constant weight supplying device.

[0020] First, we will explain the outline of this constant weight supply device. Please note that this device is divided into a supply side A that receives powder and granular material and a weighing side B that measures the weight, as shown in Figures 2 and 3.

[0021] As shown in Figure 2, the supply side A is driven by a first rotating shaft 2, and the measurement side B is driven by a second rotating shaft 3 parallel to the first rotating shaft 2. In other words, it has a two-shaft configuration with the first and second rotating shafts 2 and 3.

[0022] The rotation direction N1 of the first rotating shaft and the rotation direction N2 of the second rotating shaft are opposite to each other, and the diameter D2 of the metering side B is smaller than the diameter D1 of the supply side A.

[0023] Conversely, the diameter D1 of the supply side A can be made sufficiently large, and the problem of discharging the powder or granular material can be solved.

[0024] Although the main feature of the constant weight supplying device in this embodiment is not acquisition or control of the measured value, these will be briefly described below. As shown in Fig. 3, based on the measured value output by the load cell 12, the control unit C instructs the motor M on the number of rotations, and the motor M rotates the reducer 1.

[0025] The measured value of the load cell 12 may be either mass or weight, and a sensor other than a load cell may be used as long as it can measure with high accuracy.

[0026] The control unit C increases the rotation speed when the measured value of the load cell 12 is low relative to a predetermined fixed amount, and decreases the rotation speed when the measured value is high.

[0027] The control unit C may use, for example, proportional control, PID control, etc. However, since the present invention is not characterized by the control method, further detailed description will be omitted.

[0028] 1 and 2, the reducer 1 reduces the speed of rotation of the output shaft of the motor M according to a predetermined reduction ratio, changes the direction of rotation by 90 degrees, and rotates the perpendicular first rotating shaft 2 and second rotating shaft 3. The first rotating shaft 2 and the second rotating shaft 3 may be driven separately by independent motors and reduction ratios, but in this embodiment, a single motor M and reducer 1 are used, and a gear train (not shown) is used to reverse the directions of rotation of the first rotating shaft 2 and the second rotating shaft 3 while keeping the rotation ratio of the shafts 2 and 3 constant.

[0029] As shown in Fig. 3, supply side A is configured around the first rotating shaft 2, and metering side B is configured around the second rotating shaft 3. In terms of the vertical direction, supply side A is disposed on or above housing H, and metering side B is disposed at the same level as housing H or below it. Looking at this supply device as a whole, as shown in Fig. 1, a storage tank 4 belonging to supply side A is disposed at the top, with a powder / granular material inlet 4a opening upward. In other words, the inlet (primary side) for the powder / granular material is inlet 4a.

[0030] On the other hand, the outlet (secondary side) for the powder or granular material is a discharge port 13 of the cover 5 located at the bottom of the measurement side B (see FIG. 5).

[0031] In particular, the components of the measuring side B are stacked one on top of the other, making it difficult to understand their relative positions. Therefore, the components are shown in an exploded perspective view in FIG.

[0032] First, we will explain the configuration of the supply section A. From the viewpoint of powder and granular material, the supply section A corresponds to the first element of the entire apparatus.

[0033] As shown in FIG. 1, the supply section A has a single stage configuration, and is a set of a stirrer 6 and a storage tank 4.

[0034] The stirring body 6 has a main body 6a in the shape of a truncated cone tapered upward, and a stirring blade 6b provided at the bottom of the main body 6a so as to protrude outward.

[0035] In the illustrated example, four stirring blades 6b are provided at 90 degree intervals, but this is merely one example and various modifications are possible, for example, six or eight blades.

[0036] Next, the configuration of the weighing section B will be described.

[0037] As shown in FIG. 3, the first stage of the measuring section B is located at the same level as the supply section A or slightly lower, intersects with the supply side A and serves to take in the powdered or granular material from the supply side A, and is made up of an upper supply platen 7 journalled on the second rotating shaft 3, and an upper casing 8 having a smooth surface 8a which is in sliding contact with the underside of the upper supply platen 7 and an upper opening 8b which allows the powdered or granular material to fall through.

[0038] The second stage of the measuring section B is located directly below the upper casing 8 and transports the powder falling from the upper opening 8b. It is a set of a lower supply platen 9 journalled on the second rotating shaft 3 and a lower casing 10 having a smooth surface 10a (see Figure 5) which comes into sliding contact with the underside of the lower supply platen 9 and a lower opening 10b which allows the powder to fall through.

[0039] As shown in an enlarged view in FIG. 5, a weighing platform 11 having a load cell 13 attached thereto is disposed in front of the lower opening 10b in the rotational direction N2.

[0040] Incidentally, adjacent to the weighing platform 11 and at a position on the rear side in the rotation direction N2, a discharge port 13 is formed.

[0041] 4, the upper supply platen 7 and the lower supply platen 9 are provided with a plurality of masses 7a, 9a formed at the same position in the vertical direction, and scraper blades 7b, 9b are formed between adjacent masses 7a, 7a and 9a, 9a. In this embodiment, the upper supply platen 7 and the lower supply platen 9 are formed with six masses 7a, 7a and 9a, 9a, respectively, but the number of masses may be changed.

[0042] Next, the movement of the powdered material will be described. First, as shown by the arrow X in Fig. 1, the powdered material is fed into the storage tank 4 of the supply section A from the feed port 4a of the storage tank 4. In the supply section A, the agitator 6 rotates in the direction of the arrow N1, and the powdered material is scraped off by the agitator blade 6b and conveyed into the mass 7a of the upper supply board 7, which is the first stage of the measuring section B, as shown by the arrow N3 in Fig. 3. Here, since the rotation directions of both the rotating shafts 2 and 3 are opposite to each other, the powdered material is sandwiched between the agitator blade 6a and the scraper blade 7b, and is reliably pushed into the mass 7a.

[0043] The powder or granular material that has reached the mass 7a moves on the smooth surface 8a of the upper casing 8 as the upper supply plate 7 rotates in the rotation direction N2, and reaches the upper opening 8b.

[0044] The powder falls from the upper opening 8b to the second stage, but since the masses 7a, 9a of the upper supply platen 7 and the lower supply platen 9 are in the same position in the rotational direction and rotate at a constant speed, the powder immediately reaches the mass 9a of the lower supply platen 9.

[0045] The powder and granules that have reached the mass 9a move on the smooth surface 10a of the lower casing 10 as the lower supply platen 9 rotates in the rotation direction N2, and reach the lower opening 10b. Alternatively, the powder and granules on the smooth surface 10a are also pushed by the scraping blades 9b of the lower supply platen 9 and reach the lower opening 10b.

[0046] At the timing when the mass 9a overlaps the weighing platform 12, the weight is measured by the load cell 12, and the rotation speed is controlled as described above.

[0047] Furthermore, when the scraping wing 9b passes over the weighing platform 12 and reaches the discharge port 13, the powder on the weighing platform 12 is discharged from the discharge port 13 towards the secondary side. [Brief description of the drawings]

[0048] [Figure 1] FIG. 1 is an overall perspective view of a constant weight supplying device according to a first embodiment of the present invention; [Diagram 2] FIG. 1 is a perspective view of a constant weight supplying device showing a state in which the supply side is removed in the first embodiment of the present invention; [Diagram 3] FIG. 1 is an exploded perspective view of a constant weight supplying device according to a first embodiment of the present invention. [Figure 4] FIG. 1 is an enlarged perspective view of an upper supply board and a lower supply board according to the first embodiment of the present invention; [Diagram 5] FIG. 1 is a perspective view showing the vicinity of a lower casing of a constant weight supplying device according to a first embodiment of the present invention; [Explanation of symbols]

[0049] 1 Reducer 2 First Rotation Axis 3 Second Rotation Axis 4. Reservoir 4a Inlet 5 Cover 6 Stirring body 6a Main unit 6b Stirring blade 7 Upper supply panel 7a, 9a mass 8 Upper supply panel 8a, 10a smooth surface 8b, 10b opening 9 Lower supply panel 10 Lower casing 11 Weigh stand 12 Load Cell 13 Outlet A. Supply side B Measuring side C control section Medium motor H Housing

Claims

1. A constant weight supplying device divided into a supply side which receives a supply of powder or granular material and a weighing side which uses a sensor to weigh the powder or granular material, the supply side being driven by a first rotating shaft and the weighing side being driven by a second rotating shaft which is parallel to the first rotating shaft, the first rotating shaft and the second rotating shaft rotating in opposite directions, The metering side is formed to have a smaller diameter than the supply side, The weighing side is an upper supply platen that intersects with the supply side and takes in powder or granular material from the supply side and is journaled on the second rotating shaft; an upper casing having an upper opening that is in sliding contact with the lower surface of the upper supply plate and allows the powder or granular material to fall; a lower supply platen located immediately below the upper casing, for conveying the powder or granular material dropping from the upper opening, and supported by the second rotating shaft; a lower casing having a lower opening that is in sliding contact with the lower surface of the lower supply plate and allows the powder or granular material to fall; a weighing platform that is equipped with the sensor and that measures the weight of the powder or granular material dropped from the lower opening, The upper supply platen and the lower supply platen are provided with a plurality of equal numbers of masses formed at positions coincident with each other in the vertical direction, A constant weight supplying device characterized in that after the powder or granular material reaches the mass of the upper supply plate, the upper supply plate rotates, thereby causing the powder or granular material that has reached the upper opening to immediately reach the mass of the lower supply plate.

2. 2. The constant weight supply device according to claim 1, wherein the supply side is provided with an agitator supported on the first rotating shaft for loosening powder or granular material supplied into the supply side and transporting it to the upper supply plate of the weighing side.

3. 3. The constant weight supplying device according to claim 1, wherein the sensor is a load cell.

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