Federal Republic of Germany

                                                                                                                                              Issued on

                                                                       [emblem]                                           January 10, 1955

                                                              German Patent Office

 

                                                                        Patent

No. 921 978

                                                              Class 81e   Group 67

                                                                M 13969 XI / 81e

 

                                                Hermann Möller, Hamburg-Hochkamp,

                                                        has been named the inventor.

 

                                                    Johannes Möller, Hamburg-Altona

 

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                       Device For Pneumatic Charging of Dust-Like or Finely Granulated

                              Material from a Storage Silo to a Plurality of Storage Bins

 

Patented in the territory of the Federal Republic of Germany starting from May 6, 1952.

Patent application published on May 20, 1954.

Patent grant published on November 18, 1954.

 

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      The invention relates to a device for pneumatic charging of dust-like or finely granulated material from a storage silo to a plurality of storage bins.

      When bins are pneumatically charged with dust-like or finely granulated material, it must be ensured that following completion of the task, the charging medium - compressed air or gas - that is used is carried away without any dust. For this reason it is known to provide the individually charged bins with filters or dust separators. It is clear that pneumatic feeding and charging systems of this type will occupy a lot of space for their installation and make their manufacture much more expensive, because control units for charging the individual storage bins and also bulky and expensive cleaning systems for the conveying compressed air must be provided. This drawback occurs in such operations, where a plurality of pneumatically charged storage bins having a small holding capacity for dust-like and finely granulated material are set up very closely to each other and, moreover, only small amounts of the material have to be removed from these storage bins for use. Such operating conditions occur, for example, in forges with furnaces that are heated with coal dust.

      The object of the invention is to simplify and make more economical the prior art devices for pneumatic charging of dust-like or finely granulated material from a storage silo to a plurality of storage bins as well as the manufacture and operation of said devices.

      This problem is solved by proposing a device for automatic pneumatic charging of dust-like or finely granulated material from a common storage silo to a plurality of storage bins having a comparatively small holding and dispensing capacity. Said device is characterized in that the storage silo, which is provided in a well-known way with a dust separator, is connected to a vacuum line of a conventional type of pneumatic conveyor, from which a material-air-mixture line, constructed as the compressed air line, runs back into the silo in such a manner that the storage bins that are to be charged are connected to this line in succession one after the other, preferably arranged very closely next to each other, by means of in-feed lines, which empty freely from the top into said storage bins, and also by means of discharge lines, which run freely upwards out of said storage bins.

      One embodiment of the invention is depicted in the drawing as a schematic drawing as one example.

      Figure 1 is a side view of a pneumatic charging system; and

      Figure 2 is a view from the top;

      Figure 3 is an enlarged vertical section through a storage bin, which is depicted as a schematic drawing and exhibits its connecting lines to the pneumatic material conveying line.

      A silo system, comprising three independent silos 1 to 3, which are arranged next to each other, is filled with powdery or finely granulated material by means of any prior art charging device (not illustrated in detail) and stored therein. The silos 1 to 3 are connected together at the top by means of lines 4. The silo 3 is provided with a conventional type of dust separator or filter, through which the conveying air flows once said dust separator or filter has performed its task, before the conveying air flows into the environment. Each silo is provided at 6 with a conventional type of pneumatic or mechanical emptying device, through which the material is removed from the silos 1 to 3 and is conveyed through a line 7 into the feeding hopper 8 of a pneumatic conveyor 9, for example, a pressure feeder.

      The reference numeral 10 denotes the feeder, driven by a motor 11; 12 is a mixing head, into which the compressed air from a compressed air system (not illustrated here) is fed via the line 13. Attached to the mixing head 12 is a conveying line 14 for the mixture of material and air that is formed in said line. The line 14 runs in the operating room of the storage bins 15 and then empties into the silo 1.

      As the mixture of material and air passes in the direction of the arrow through the conveying line 14, the storage bins 13 are connected, as evident from the enlarged drawing in Figure 3, to the conveying line 14 by means of a branch line 16, which feeds the material into the storage bins, and a branch line 17, which in turn carries away the dust-laden conveying air after the work is completed. The branch lines 16, 17 empty freely from the top into the storage bins 15. That is, there are no control units or cleaning elements or any other impeding installations in either the in-feed lines or the discharge lines 16, 17 or in the common line 14 for all of the storage bins. The in-coming material and the out-going conveying air are indicated by the arrows in Figure 3. According to the invention, the storage silos 1 to 3, the pneumatic conveyors 8 to 12 and the storage bins 15 are connected together, as described, in series one after the other by an annular line 14 for the material/air mixture so that the device functions as follows

      Given the assumption that all of the storage bins 15 are empty: when the feeder 10 is put into operation, the air conveys first just the material into the next closest storage bin 15. The material settles in said bin; and the dust-laden conveying air escapes through the branch line 17 into the material/air line 14 and flows through the storage silos 1 to 3 and the dust separator 5, in which all of the dust is removed from the air; and then the air flows in this cleaned state into the environment. If the first storage bin 15 is totally full, the conveying of material into said bin stops automatically. The air conveys the material past the filled storage bin to the next bin until the second storage bin 15 is filled. This procedure continues until all of the storage bins are filled. If in the interim a storage bin is totally or partially emptied by removing material from the bottom at 18, then it fills ups automatically again, as described above.

      A temporary surplus of material to be conveyed at all of the filled storage bins is carried back into the storage silos 1 to 3 via the line 14.

      It is self-evident that the silo system may consist of a single silo or any number of silos.

      A charging system, according to the invention, does not need either control units for charging the individual storage bins or bulky and expensive cleaning systems for the conveying air, since only the storage silo or the last silo of a silo system has to be provided with a dust separator or a filter.

      A charging system, according to the invention, is especially appropriate for such operations, in which a larger number of storage bins, which are arranged very closely next to each other, have a small holding capacity and are set up for the purpose of removing small amounts.

 

                                                                    Patent Claim:

 

      Device for automatic pneumatic charging of dust-like or finely granulated material from a common storage silo to a plurality of storage bins having a comparatively small holding and dispensing capacity, characterized in that the storage silo (1 to 3), which is provided in a well-known way with a dust separator (5), is connected to a vacuum line (7) of a conventional type of pneumatic conveyor (8 to 12), from which a material-air-mixture line (14), constructed as a compressed air line, runs back into the silo (1 to 3) in such a manner that the storage bins (15) that are to be charged are connected to this line (14) in succession one after the other, preferably arranged very closely next to each other, by means of in-feed lines (16), which empty freely from the top into said storage bins, and also by means of discharge lines (17), which run freely upwards out of said storage bins.

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Documents taken into consideration

German patent nos. 502018, 489542, 256661.

 

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                                                                                       1 page of drawings

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