Патент USA US2121787код для вставки
June 28, 1938‘. _ v E. H. DAHLGREN _ . 2,121,787 METHOD‘ AND APPARATUS FO-R DETERMINING THE MIGRATION 0F FISH ' Filed Nov. 25, 1956 2P - . ‘ /P1 0000 my; 1’ 5 F1 T ’T F2, INVENTOR ,5“ I _ BY EDWIN H.DHHLG:REN ATTORNEY ‘2,121,737 Patented June 28, 1938 ‘ sTArE 2,121,787 METHOD AND APPARATUS FOR DETERMIN . ING THE MIGRATION OF FISH Edwin H. Dahlgren, Seattle, Wash., assignor to Government of the United States, as repre sented by the Secretary of Commerce Application November 23, 1936, Serial No. 112,208 4 Claims. (Cl. 175-265) (Granted under the act of March v3, 1883, as ' 7 amended April 30, 1928; 370 0. G. 757) and R2 connected through sources of current S . The invention described herein may be manu- , to electromagnets 9 and I0 operating spring con , factured and used byor for the Government of the United States for governmental purposes trolled armatures II and I2 mechanically at tached to the ejector gates 3 and 4 so that when ' without the payment to me of any royalty there either'of the relays I and 2 is operated by the dif U ampli?er and selector system DAS, the My invention relates speci?cally toa method ferential, ejector gates 3 and 4 move to the position shown and apparatus for determining the migration of in dotted lines and designated 3', 4'. It is to be ?sh, but is applicable generally to the detection understood, however, that other means than of the presence of any of the ferro metals. those illustrated may be used to mechanically 10 As previously practiced by the Bureau of Fish 10 or electrically operate the ejector gates 3 and 4. cries of the United States Department of Com merce,v migrating ?sh having been identi?ed by ' The operation of my system and method is as on. r ' . follows: ' ‘tags attached by clips to the tails, these tags so balanced that no current ?ows in the primary 15 and unnecessary destruction of ?sh through‘in P1 of the transformer T1. When a number'of ?sh, including one or more, bearing identi?cation ; fection, as Well as loss of identi?cation tags due to-the fact that the tags tear out of the ?esh. anced so that if the ?sh passes between the coils 20 ing' of the tags to the tails causes ?esh injury 220 ' The bridge system comprising coils 5, 8, ‘I, 8 is being recovered from the'?sh meal after the ?sh 15 are processed at the packingplants; The attach tags passes through the conveyors or sluiceways 1' l and 2, the impedance of the bridge is unbal Inmy method andapparatus I insert into the body cavities of the ?sh small ferro metal tags bearing identifying serial numbers, the tags lye ing between ‘thebody wall and the visceral or 6 and ,1, relay R1 is operated to open the ejector gate 3. If the ?sh carrying themetal identi?ca tion tag passes through the conveyor or sluiceway 2, the bridge is unbalanced so that the relay RF is operated, opening ejector gate 4. A number of different types of apparatus differing in details gans, and on the recapture of the ?sh oh the ?sh ing grounds‘electrically identify, the ?sh by the presence of the tags,‘recovering them beforethey are processed. H ' ' of construction are known to me which will selec ' In carryingout this method I have provided an ' apparatus, an example of which I have illustrated tively identify the ?sh bearing the identi?cation tags. It is to be understood that many of thesedi?er 30 ent detail forms of apparatus may ,be employed I and 2 designate conveyor chutes or sluiceways. in connection with my invention without depart through which the ?sh are passed. The convey ing‘ from the scope of the claims appended hereto ors are provided with ejector gates 3 and 4 which which are as follows: are operated by an electrical system, such, for ex . in the accompanying drawing wherein numerals ample, as an impedance bridge preferably com prising coils 5, 6, ‘l and 8, pairs of which, 5 and 8, "I claim: ' 1. In an apparatus for identifying ?sh bearing metal identi?cation tags, the combination of a ‘ 'l and 6, are located opposite the sluiceways so I conveyor having an ejector gate, a balanced elec ‘that the ?sh bearing the identi?cation tags may change the impedance of the system, thus operat 40 ing the ejector gates‘ 3 and 4. I As illustrated, the input system for the imped ance bridgevéomprises a transformer T coupled to a .source of alternating current S, which ap plies potential to the common terminals of coils trical circuit positioned adjacent said conveyor whereby the‘ presence of said ?sh bearing the metal identi?cation tags unbalances said electri- , cal‘ circuit, and means coupling the output of said balanced electrical circuit for operating said ejec- V tor gate. . . 2. The step in the method of determining the 45 »5, 6 and 1, 8, respectively; Thejoutput of the migration of ?sh which consists in identifying bridge coupled to the common vconnection be ?sh by inserting metallic identi?cation tween the coils 5,1 and 6, 8, respectively, includes ' certain pieces within the body cavities lying between the the primary P1 of the transformer T1. 7 The sec; ondary of the transformer T1 is a compound sec ondary'sl, coupled in this instance to a differ 45 ' body walls and the visceral organs of the ?sh. 3. The steps in the method of determining the 50 ential, ampli?er'and selector DAS, the output of _migration of ?sh which consists in identifying which operates relays R1 and B2 mechanically certain ?sh by inserting metallic identi?cation pieceswithin the body cavities of the ?sh and on ‘ or‘ electrically connected to the ejector gates 3 recapture electrically segregating the ?sh bear .and 4 in the conveyors or sluiceways ‘I and 2.» 55 In the drawing I have illustrated the relays R1 ing the metal identi?cation pieces. 55 2 > 2,121,787 4. The steps in the method of determining the migration of ?sh which consists in identifying certain ?sh by inserting ‘metallic identi?cation pieces within the body cavities lying between the Cl body wall and the visceral organs of the ?sh and on recapture electrically segregating the ?sh bearing the metal identi?cation pieces by pass ing the same through a balanced electrical sys tem whereby the presence of the ?sh bearing the identi?cation pieces unbalances said electrical system. ‘ EDWIN DAHLGREN.