JPH048335B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is a pneumatic transport type powder and granular material quantitative supply device that immediately conveys powder and granular material discharged by a quantitative supply device through a pneumatic transport pipe. The present invention relates to a powder and granular material quantitative supply device having a structure in which the amount of powder and granular material supplied can be measured by measuring the weight of the device.

[Conventional technology]

In conventional powder/fluid quantitative supply devices, the total weight of the storage chamber, quantitative supply mechanism, and their auxiliary equipment is measured using a weight detector such as a load cell, and the amount of powder/granular material supplied is calculated from the weight reduction. Furthermore, Japanese Patent Application Laid-Open No. 57-98425 discloses an apparatus that separates a powder feeder from peripheral equipment and structures using a flexible pipe and measures the weight to calculate the powder feed amount.

[Problem that the invention seeks to solve]

If such a method for measuring the supply amount of powder or granular material is adopted in a pneumatic transport type powder or granular material quantitative supply device, the high pressure air of the pneumatic transport pipe will act on the storage chamber and the quantitative supply mechanism, causing a large error in weight measurement. In addition, the air pressure on the input hopper side that charges the powder into the storage chamber also acts on the storage chamber, and the differential pressure with atmospheric pressure also causes errors in weight measurement. Furthermore, since the storage chamber and the powder/granular material input pipe and the storage chamber and the air transport pipe are connected, there is a problem in that the weight of these peripheral devices is also measured. Furthermore, the device disclosed in Japanese Patent Application Laid-Open No. 57-98425 is
It has a structure in which a flexible pipe and a valve provided below the flexible pipe are provided in the powder/granular material input path between the hopper and the storage chamber. With this structure, even when the valve is closed, the flexible pipe is filled with powder from the hopper, and the powder pressure and air pressure on the hopper side are loaded into the storage chamber through the valve. There is a problem in that the influence is reflected on the weighing scale, making it impossible to accurately calculate the powder fluid supply amount. The present invention aims to provide a pneumatic transport type powder/granular material quantitative supply device having a structure that can measure the accurate powder/granular material supply amount by skillfully solving the influence of the air pressure and the weight of peripheral equipment. A pneumatic transport type quantitative feeding device that has a fixed amount feeding mechanism 2 in the lower part of a storage chamber 1, and discharges the powder and granules transferred by the fixed amount feeding mechanism directly into a pneumatic transportation pipe 3 arranged close to the storage chamber. In this process, the inlet 4 of the storage chamber 1 and the powder/granular material input pipe 5 are connected via a flexible duct 6 midway to form a powder/granular material input path, and the powder/granular material is inserted into each side of the flexible duct 6. Valves 7 and 8 are provided to open and close the body input passage in an airtight manner, an atmosphere release passage 9 is provided to communicate the powder and granular material input passage space between these two valves 7 and 8 to the atmosphere, and an air transport pipe 3 is provided. The flexible ducts 10 and 11 are interposed before and after the discharge position, and the air transport pipe mixing part 12 between the flexible ducts 10 and 11 is fixed to the quantitative supply device, and the air in the air transport pipe 3 and the air in the storage chamber 1 are A weight detection system is provided to measure the total weight of the storage chamber 1 containing the powder and granular material, the constant supply mechanism 2, the air transport pipe mixing section 12, the lower valve 7, and these attached devices. The present invention is a pneumatic transportation type powder or granular material quantitative supply device, which is equipped with a container 14 and measures the amount of powder or granular material supplied from a change in the weight measured by the same weight detector.

[Effect]

In this invention, the flexible duct 6 isolates the weight between the storage chamber 1 side and the powder/granular material charging pipe 5 side, so that the weight of the powder/granular material charging pipe 5, the powder/granular material inside it, and the charging hopper equipment is reduced by the weight. The flexible duct 1 prevents any load from being applied to the detector 14.
0 and 11, the weight of the air transport pipe 3 excluding the air transport pipe mixed part 12 is blocked, and the weight detector 14
It is made so that it is not loaded.

Next, when the amount of granular material in the storage chamber 1 decreases significantly, the valves 7 and 8 are opened, and a predetermined amount of granular material is introduced into the storage chamber 1 from the granular material input pipe 5. After that, the valves 7 and 8 are closed, and the air release path 9 is opened to make the air pressure in the powder input path space between the valves 7 and 8 atmospheric pressure, and the air pressure that acts on the storage chamber 1 side via the lower valve 7 In addition, the upper valve 8 shuts off the powder and the air pressure above the powder input path, so that the powder fluid pressure and air pressure do not act on the flexible duct 6. Furthermore, the air in the air transport pipe 3 is stored in the storage chamber 1.
By communicating with the air inside the air transport pipe 3
The air pressure inside the storage chamber 1 is made equal to the air pressure inside the storage chamber 1, so that the air pressure in the air transport pipe 3 cancels out the air force acting on the storage chamber 1 side via the quantitative supply mechanism, so that no load is applied to the weight detector 14. Make it. At the same time, by making the air pressures of the storage chamber 1 and the air transport pipe 3 the same, disturbances in the movement of the powder and granules are eliminated. In this way, the amount of change in the weight value measured by the weight detector 14 can be accurately measured as the amount of change in the powder or granular material, that is, the amount of powder or granular material supplied.

〔Example〕

The metering mechanism of this embodiment has a structure in which a rotary supply plate 17 is provided at the lower part of the storage chamber 1, with blades 15 protruding from the outer periphery and a square space 16 for storing powder between the blades. The weight detector 14 uses a load cell and is placed under an arm 18 that projects from three locations on the outer wall of the storage chamber 1 and suspends the entire storage chamber in the air.
The total weight of the storage chamber 1, the powder and granular material contained therein, the quantitative supply mechanism 2, the valve 7, the air transport pipe mixing section 12, and their attached parts is measured. The powder supply amount is calculated from the measured weight decrease. If necessary, the rotation speed of the rotary supply board 17 is controlled so as to reach the target powder supply amount. The on-off valves 22 and 23 are ball valves provided in the air transport pipe 3.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to prevent the weight of the storage chamber 1, quantitative supply mechanism, and peripheral equipment members connected to the mixing part of the air transport pipe from being picked up, and the air pressure on the side of the air transport pipe and the powder/granular material input pipe can be prevented. This prevents the weight from loading on the weight detector, and equalizes the air pressure in the air transport pipe and storage chamber to eliminate disturbances in the transfer of the powder and granules, making it possible to accurately measure the powder and granules being discharged. .

[Brief explanation of drawings]

Fig. 1 is a front view showing an embodiment of the pneumatic transportation type powder/grain material quantitative supply device of the present invention, Fig. 2 is a plan view of the same, and Fig. 3 is a plan view of the same.
The figure is a longitudinal cross-sectional view showing the quantitative supply mechanism, and Figure 4 is the first
FIG. 3 is an enlarged cross-sectional view along the line. 1: Storage chamber, 2: Quantitative supply mechanism, 3: Air transport pipe, 4: Inlet, 5: Powder input pipe, 6: Flexible duct, 10, 11: Flexible duct, 12: Air transport pipe mixing part, 13: Pressure equalization pipe, 1
4: Weight detector.

Claims (1)

[Claims] 1 A pneumatic transport type in which a fixed amount supply mechanism 2 is provided at the lower part of the storage chamber 1, and even if the fixed amount supply mechanism is used, the powder or granular material to be transferred is directly discharged into the pneumatic transport pipe 3 located close to the storage chamber. In the fixed quantity supply device, the input port 4 of the storage chamber 1 and the powder/granular material input pipe 5 are connected via a flexible duct 6 midway to form a powder/granular material input path, and each side of the flexible duct 6 is Valves 7 and 8 are provided for airtightly opening and closing the powder and granular material input passage, and an atmosphere release passage 9 is provided that communicates the powder and granular material input passage space between these two valves 7 and 8 with the atmosphere. Flexible ducts 10 and 11 are interposed before and after the discharge position of the transport pipe 3, and the air transport pipe mixing part 12 between the flexible ducts 10 and 11 is fixed to a quantitative supply device, and the air in the air transport pipe 3 and the storage chamber 1 are fixed. A pressure equalizing pipe 13 is installed to communicate with the air inside, and the total weight of the storage chamber 1 containing the powder and granular material, quantitative supply mechanism 2, air transport pipe mixing section 12, lower valve 7, and these attached devices is measured. 1. A pneumatic transportation type powder or granular material quantitative supply device, which is equipped with a weight detector 14 that measures the amount of powder or granular material supplied from changes in the measured weight of the weight detector.