Патент USA US2412712код для вставки
Dec. 17, 1946, C. W. BROWN METHOD OF ASSEMBLING FUSE LINKS Flled July 27, 1942 2,412,712 2 Sheets-Sheet 1 if? / 17 INVENTOR. Dec. 17, 1946. c, w_ BROWN I 2,412,712’ METHOD OF ASSEMBLING FUSE LINKS Filed July 27, 1942 2 Sheets-Sheet 2 155 \ m, I" Patented Dec. 17, 1946 2,412,712‘ UNITED STATES ‘PATENT OFFICE 2,412,712 METHOD OF ASSEMBLIN G FUSE LINKS Chester W. Brown, Milwaukee, Wis., assignor to Line Material Company, Milwaukee, Wis., a corporation of Delaware 1 Application July 27, 1942, Serial No. 452,436 6 Claims. (Cl. 29—155.5) 2 This invention relates to the production of spring fuse-links of the type and species illus trated and described in Steinmayer U. S. Patent No. 2,270,225; and it has to do with an improved method of manufacture, and particularly a more facile and speedy method of assembling the com ponent parts of such fuse-links. The object, of otherwise securing to one end of leader I 1 the strain wire 18 and fuse wire l?—the latter being twisted around the strain wire as shown. The second step is illustrated in Fig. 2 and con sists merely in adding spring E55 by threading therethrough the strain wire and fuse wire. The third step, depicted in Fig. 3, consists in course, is to effect a reduction of manufacturing inserting the free ends of the strain wire and cost. fuse wire into the tubular shank of terminal In the drawings which accompany this speci? 10 member is and locally prick-punching said shank cation at 13d in the manner portrayed in the cross—sec tional detail Fig. 4. This results in ?rmly an choring the strain and fuse wires to the shank of Figs. 1 to 7, inclusive, illustrate successive op rations or steps in the course of assembly of a fuse-link, conformably to the present invention; Fig. 8 is a sectional view of a ?attening die, taken along the line 8-8 of Fig. '7 ; Fig. 9 is a sectional view of the ?attening die taken along the line 9-9 of Fig. 8; and Fig. 10 is an elevational view, partly in section, of a completed fuse-link. 1 Fig. 11 is an enlarged sectional view take along the line I l—-I l of Fig. 10. the terminal member. The fourth step consists in inserting the as sembly of Fig. 3 into tube it‘ as illustrated in Fig. 5. The ?fth step consists in screwing nut I6 onto the lower end of spring l5 as depicted in Fig. 6. 20 Thereafter, as a sixth and ?nal step, terminal " It is believed most expedious to describe first the completely assembled fuse-link shown in Fig. 10 and, thereafter, to proceed step-by-step with a description of the assembling operations. Referring to Fig. 10, the fuse-link shown com prises a ?bre protector tube l2, an upper terminal member I 3, a fusible section l4, and expulsion spring 15, a nut 16, and a ?exible leader [1. 30 Terminal member I 3 includes a conventional button-head contact l3a, a tubular shank portion which is flattened at 13b from just below the button head contact to just above the upper end of protector tube 12. Portion I30 of the ter minal member is not ?attened but is deformed, as shown in cross-section in Fig. 4, to grip the upper ends of. a strain wire 18 and a fuse wire l9 constituting fusible section [4. Portion I30 is, member I3 is pulled longitudinally and outwardly of tube 12 and the tubular shank portion is ?at tened at [312, as shown in the cross-sectional view, Fig. 11. The ?attening of the shank is effected in a press (not shown) by means of a punch 29 and dies or anvil 2i shown in Figs. 7, 8, and 9. The punch is a simple metal ?attening tool, the working end of which only is illustrated. The upper portion of the punch is, of course, secured to the ram of the press. Die 2i comprises a base portion 2m which is secured in any appropriate manner to the bed or platen of the press in proper alignment with the punch. Forming an integral part of and projecting upwardly from the base portion of the die is a pad 2| b having a ?nished top surface. At one end of pad Zlb is a pair of spaced upwardly extending ears 22 and 23 which may be welded or otherwise se cured to the base. The spacing between the lat ters ears is su?icient to clear and permit inser tion therebetween of the portion l3e of button in the main, cylindrical and a close ?t in the bore of protector tube I2. The lower ends of strain wire it’ and fuse wire head contact lsa. t the other extremity of pad H! are soldered to the adjoining end of ?exible 2|b are disposed a second pair of spaced up leader H’. standing ears 2-’! and 25. These are aligned with The upper end of expulsion spring i5 is con 45 cars 22 and 23 respectively and the spacing be stricted to form an abutment for the upper end tween them is such as to clear the tubular shank of the leader; and nut l8 functions to anchor portion I32). the lower end of the spring and normally retain The extent to which tubular shank portion l3c it under tension. The strain wire normally is extends into the bore of tube | 2 and, incidentally, under a predetermined tension effected by the ex— 50 the tension applied to spring I5 is determined by pulsion spring, and, in event the fusible section the separation, longitudinally of the fuse-link, blows, the leader is quickly expelled from the tube between the pair of cars 22, 23 and the pair of by the spring. The fuse-link structure just de cars 24, 25. The latter are beveled at 24c and scribed is substantially identical with the dis 25a so that the ?owing metal resulting from the closure of the above mentioned Steimnayer Pat ?attening operation will not make it di?icult to ent No. 2,2'70,225—tl1e sole novelty residing in the remove the fuse~link from the die. A knock-out improved manufacturing method which now will for ejecting the fuse-link from the die may be be explained. employed if desired. This is in keeping with The ?rst step-of the assembling operation is well-known die-making practice and needs no illustrated in Fig. l and consists in soldering or 60 illustration. 2,412,712 3 What is claimed is: l. The method which includes the following enumerated steps: (1) making a sub-assembly comprising a relatively elongate terminal mem her, a fusible section connected at one end only, to one end of said terminal member, a conductive eader connected at one end only to the other 4. The method which includes the following enumerated steps: (1) attaching end to end a ?exible conductive leader and a fusible section comprising a'fuse wire and a strain wire in par allel; (2) adding to the assemblage of step (1) a helical spring encircling the conductive leader and having one end anchored to the junction be tween the conductive leader and fusible section, said spring extending from said junction away spring anchored at one end only to said conduc tive leader and extending, from its anchorage, 10 from said fusible section; (3) inserting the end of said fusible section remote from said conduc along said leader and co-axially therewith and tive leader into one end of an elongate tubular away from said fusible section; (2) inserting terminal member and prick-punching said tubu telescopically into the bore of a protector tube, lar terminal member laterally to grip the in the sub-assembly of the?rst step so that the ter minal member extends into one end of the tube 15 serted end of the fusible section; (4:) inserting telescopically into the bore of a protector tube while the free end of the spring projects out of the ‘assemblage resulting from the three above the other end of the tube; (3) anchoring the enumerated steps so that the tubular terminal aforementioned free end of the spring. to the ad member extends into one end of‘the protector jacent end of the tube; (4) applying tensile force tube while the end of the spring remote from the axially to said terminal member in a direction to fusible section is outside the other end of the effect tensioning of said spring and resultantly protector tube; (5) anchoring the last-men to effect a partial withdrawal of said terminal tioned end of the spring to that end of the pro member from the bore of the tube and; (5) dis tector tube which is remote from said tubular torting said terminal member outside the bore ‘and adjacent the end of said tube from which 25 terminal member; (6) applying tensile force axi ally to said terminal member in a direction to it projects to form a stop engaging said tube for sheet tensioning of said spring and resultantly to maintaining said spring under tension. effect a partial withdrawal of said terminal 2. rI‘he method which includes the following member from the bore of the protector tube and; enumerated steps: (1) making a. sub-assembly comprising a relatively elongate terminal mem 30 (7) ?attening said terminal member outside the bore and adjacent that end of the protector tube her, a fusible section connected at one end only from which it projects to form a shoulder engag to one end of said terminal member, and a heli ing the last-mentioned end of the protector tube cal spring connected at one end only with the for maintaining said spring under tension. other end of said fusible section; (2) inserting 5. The method of tensioning a fuse link com telescopically into the bore of a protector tube prising a terminal, a. leader, and a strain section the sub-assembly of the ?rst stepv so that the mechanically and electrically connecting said terminal member extends into one end oi‘ the terminal and leader and including a coil spring tube while the free end of the spring projects out surrounding said leader and anchored thereto ad of the other end of the tube; (3) anchoring the jacent said section; said method comprising, ?rst, aforementioned free end of the spring to the end the mounting of a tube on said leader and mov of the tube adjacent thereto; (4) applying tensile ing it to a position embracing said terminal, force axially to said terminal member in a direc strain section, and a portion of said spring; sec tion to eiTect tensioning of said spring and re ond, the mounting of a nut on the projecting sultantly to e?ect a predetermined partial with end of said spring; third, the moving of the tube ‘drawal of said terminal member from the bore to cause expansion of said spring axially; and, of the tube and; (5) compressing said terminal fourth, the deforming of said terminal to provide member laterally to form one or more shoulders ‘tube engaging means for holding tle tube in thereon immediately adjacent the end of said spring expanded position. ' ' tube to prevent contraction or said spring ‘and 6. ‘The method of assembling a spring ten thereby normally to maintain said spring under sioned fuse link, said method comprising in se quence as follows: ?rst, securing a ?exible cable 3, The method which includes the following and strain wire together in end to end relation; enumerated steps: (1) making a sub-assembly second, passing the strain wire and a portion of comprising a relatively elongate terminal mem end only of said fusible section, and a helical tension. ‘ ' ber, a fusible section connected at one end only to one end of said terminal member, and a hell cal spring connected at one end only with the other end of said fusible section; (2) inserting telescopically into the bore of a protector tube the sub-assembly of the ?rst step so that the ter minal member extends into one end of the tube while the free end of the spring projects out of the other end of the tube; (3) attaching the pro jecting free end of the spring to a nut for an choring the spring to the end of the tube adja cent thereto; (4) applying tensile force axially to said terminal member in a direction to effect the cable through a coil spring and engaging one end of the spring with the juncture between said cable and wire; third, passing the end of said wire remote from said cable into a tubular ter minal and deforming the end of the latter nearest said cable to secure it to the wire; fourth, pass ing the cable, spring, wire, and terminal through a protectivetube until a portion of the spring is exposed at the trailing end of said protective tube; ?fth, passing'said cable through a nut and screwing said out upon the exposed end of said spring; sixth, pulling the major portion ‘of said terminal from said protective tube and coinci~ dental therewith stressing said spring through the medium of said protective tube and nut; and tensioning of said spring and resultantly to effect a predetermined partial withdrawal of said ter zrinal‘member from the bore of the tube and; 70 seventh, ?attening the exposed. intermediate por tion of said terminal to spread it laterally into (5) ?attening the terminal member outside the position for endwise engagement with said pro bore. of said tube and immediately adjacent the tective tube. end thereof to form stop means for normally re CHESTER W.’ BROWN. _ taining said spring under tension.