USRE22747E - Cut-out construction - Google Patents

Description

April 946. w. o. SCHULTZ EIAL Re. 22,747

CUT -OUT CONSTRUCTION Original Filed Feb. 6, 1943 4 Sheets-Sheet 1 IT k T ORNEY.

April 23, 1946 w. o. SCHULTZ EIAL Re. 22,747

CUT-OUT CONSTRUCTION Original Filed Feb. 6. 194:5 4 Sheets-Sheet 2 INVENTORS [WU/AM 0. 60/0172 BY flZll/l/V 6. S/El/VMAYL'K AT RNEY,

w. o. SCHULTZ ETAL Re. 22,747

April 23, 1946.

Original Filed Feb. 6, 1943 w a 1 2 z 5 I Y 3 1v S\\\\\\\\\\\\\\ m a 1 a w w w a 0 w a an ,emz /a A TORNEY.

April 23, 1946. w. o. SCHULTZ ETAL 22,747

CUT-OUT CONSTRUCTION Original Filed Feb. 6, 1945 4 Sheets-SheetA BIY 22.. A 2J",,,j/,4,4

ATTORNEY Reissued Apr. 23, 1946 William 0. Schultz, South Milwaukee, and G. Steinmayer, Milwaukee, Wis, assign lrs to Line Material Company, Milwaukee), Wis, a. corporation of Delaware Original No. 2,362,314, dated. number, '1. .19.44,

Serial No. 474,938, February 6, 1943.

Application for reissue January 31,1946 Serial, No.

644,605 17 Claims.

This invention relates to cut-out constructions.

The. primary object of this invention is to provide a cut-out which: operates as a drop-out fuse device under electrical overload and-which also may be operated manually to open the circuit under loan withoutd'amage to the apparatus.

Further objects are: to provide a device as set forthhereinabove which is somade that the fuse link construction is not damaged when the device is. manually operated under load but in which means are provided for reestablishing the position of the use construction for further service afterthe device has been manually operated so thatthe. same iuse construction can be used over and: over unless such fuse construction has been ruptured by an electrical overload in the automatic operation of the apparatus.

Further objects are to provide a construction in which the circuit isinterrupted Within the fuse tube whether the cut-out is operated automatically upon electrical overload or manually during load, the construction also providing for the automatic outward and downward dropping of the cut-out after the clrcuit' has' been first ruptured within the tube itself, the construction insuring for the expulsive arcextinguishing action whether the circuit is openedmanuall or automatically.

Further objects are to provide a cut-out construction which may employ a simple type of rigid upper stationary contact, which is so made that the fuse tube may be repositioned by means of a switch stick although it is equipped for both manualand automatic operation as the ordinary type of fuse device, and which is adapted when manually operated to be manipulated by means of a switch stick so that the operator is out of the danger zone at the time the cut-out interrupts the circuit. Further objects are to provide a cut-out con... struction which has both the automatic operation under electrical overload and the manual operation and in which a part at least of the composite fuse link construction is drawn upwardly into the fuse tube. when the device operates automatically, and in which the lower portion of the composite fuse link construction is bodily drawn upwardly into the fuse tube, when the device is manually operated, thereby securing in both cases a certain and assured clearing of, the circuit within. the fuse tube itself prior to the outwarddropping of thefuse tube.

Further objects are to provide; a construction which although having the features of both auto-- matic and manualoperation is nevertheless of relatively simple construction.

Embodimentsof the invention are shown in the accompanying drawings, in which:

Figure-l5 isaside elevation of one form, of the a paratus showing the device in closed position.

Figure- 2 is aview, partlyi'n section and partly broken away, showing the device while it is being manually operated.

Figure 3 is a bottom view; of the device.

Figure i is a view, partly broken awa and partly insection, showing'the device after it has dropped to open position.

Figure 5 is a sectional, view on the line 55 of Figure 1.

Figure 6" is a fragmentary view of a modified form of the invention.

Figure '7 is a fragmentary view, partlyin section, of the lower portion-pf a further modified form 'of the invention.

" Figure 8" is a bottom shown in Figure Z.

" Referring to Figures 1 to 5, it will be seen that the cut -out comprises a suitable support, such as an elongated insulator I, which may be supported intermediate its ends in any suitable manner as by means of the clamp 2. The upper end of the insulator carries the upper terminal indicated generally at 3- and the lower end of the insulator carriesa lower terminal indicated generally at. 4. The upper and lower terminals are provided with apertures 5 for the reception of connectors and one or both of the terminals may be provided with a tie. eyelet portion indicated at 6 for the upper terminal;

The upper terminal extends outwardly and terinmates in an upwardly bevelled lip portion I which is provided with an upwardly recessed portion 8 and with a stop flange 9 rearwardly of such depression. i

The lower terminal 4 is provided with a pair of hook-like members or supporting members 10 which arejoined bymeans of a flange portion i l The cut-out comprises a fuse tube I 2 of fiber or suitable material provided with an upper terminal l3 including the clamping cap 14 which has a rounded upper end normally fitting beneath the recessed 0r latching portion 8 of the upper stationary terminal. A manipulating eyelet portion l5 is formed integrally with the upper fuse terminal l3. 7

The. lower portion of the fuse is provided with a collar [8 rigidly secured thereto which is equipped with a. manipulating eyelet IT on its outer side and with a. manipulating eyelet porview of the structure tion I 3 on its inner side. The eyelet portion I8 is formed in the arm I9 which is integral with the sleeve I6. This arm extends rearwardly and downwardly and is provided with pivot pins 29 projecting from opposite sides thereo f. These pivot pins'e'xtend outwardly from tneg' namder'ed portions 2| 'of the arm 19, as shown most-clearly in Figure 2, the shouldered portions 2| constituting spacing members and being located between the channel like walls 22 of a lever 23. yThe lever 23 is provided with slots 24 within which the pivot pins 20 are slidably and'pivotally mounted.

. fuse tube.

The operation of the apparatus under over- 'load is as follows: When an overload occurs, the

, fuse link 39 and strain wire 38, see Figure 5, are

The lever 23 is also providedwith outwardly pro Q;

jecting trunnions 25 which are removably seated in the hook like supporting members [0. The

lever 23 at its rear portion is provided with a rounded flange 26 which is positioned beneath 1 the flange II and assists in "preventing upward recoil when the fuse blows and alsoprevents inadvertent detachment of the trunnions "from the hook supports I0 until the device has been rocked downwardly, for example as shown in Figure 4. The lever 23 may be provided with an upwardly extending arm 23' which has a curved flange portion loosely surroundinga part; of the collar I5. 7 v

It is to be noted that the lever-23 extends forwardly beneath the lower end of the fusetube and is provided with a pair of fingers constituting a slotted or forked end 21, seeparticularly Figures 2 and 3. If desired, the lever 23 may be provided with a downwardly extending ,web 28 which will limit the rearwardrocking of thelever when the fuse tube first drops downwardly to its lowest position, as such web will engage the flange II ifthe fuse tube and lever rock to the left past the position shown inFigure 4.

The fuse tube encloses a fuse link construction whichincludes a buttonhead; 29 clamped between the cap I 4 and the sleeve I3 at the upper end of the fuse tube I2. A flexibleleader 30 extends downwardly from the cap 29 andthro'ugh a tension spring 3|. The lower end of the tension spring is secured-to an internally threaded collar 32 constitutingthe lower terminal of the flexible leader 30.

The fuse unit itself is removable and comprises an upper cylindrical member 33 provided with a threaded stem 34 removably: screwed-into the member 32. A metallic sleeve 35 is-fianged over the upper end of the member. 33 and; extends downwardly and has preferably a tight fit with a small fiber tube 36. A metallic rod-31 extends upwardly into the small fibertube 35- and is slidable outwardly from said tube; It is held in place by means of the strain wire 38 and is also connected to the member -33 by means of the fuse wire 39. The rod- 31 extends downwardly out of the lower end f the-fuse tube and is pro-' vided with a centering collar 40 for centering the fuse link with reference to the outer or -main fuse tube I2 Below the collar the rod is provided with a reduced portion 4| and with a lower collar 42 which has a bevelled upper surface as indicated at 43. A manipulating rod 44 is either permanently or removably secured within the collar 42. In the form shownin Figure-'5 the manipulating rod- 44 is permanently secured within the collar"; The rod, as stated, may beremovablysecured as will appear from-the description of Figure 7 hereinafter.

Itis to be-noted that the metallic sleeve I 6 rigidly secured to the lower end'of'the fuse tube has a lower flange. portion 45 which-extends beneath the-lower-end of the fusetube; This lower ruptured andthe' spring 3| draws the members 32 and 3a and the. small fiber tube 36 upwardly into the main fuse tube l2. The rod 31 is expelled downwardly andalso is pulled downwardly by means o f the lever-23, it being noted that the weight of the fus'eatube and its associated parts,

a's"w'ell as 'thelwei'ght of the lever 23, biases the lever towardsdownward motion. It is apparent,

therefore, that when the fuse link is ruptured,

the rod 3;! moves downwardly and @release'sthe lever,23 which upons'rockingdownwardly moves the lower end of the fuse 'tubedownwardly and outwardly and allows the upper. cap I4 of the upper terminal of the fusetube to detach itself from the latching portion 3 of the upper stationary terminal 3. The fuse tube thendrops downwardly to the position-shown inrFigure 4. i

In this position, it is obvious that the .fuseztube may be lifted from the hook supports III. by means of a switch stickcoacting with-the eyelet portion l8 of the arm I9, The fuse tube is then re-fused and replaced. t

The device has another mode of operation when it is desiredto manually. open the circuit under load, The initiating-of this mode ofoperation is shown in Figure 2 wherein the switch stick indicated in dotted lines at 46 is hooked into the outer lower eyeletv II at the lower end of the fuse tubev and the fuse tube is then, drawn to the right as viewedin F igure ll. This causes the collar 42' to slide outwardly from the forked end 21 of the lever 23 and the coil spring or tensionspring '3 I immediately draws the lower portions of the composite fuse link structure up-. wardly'into the main fusetube .42. -'I' l'1e initial arc strikes between. the rod 31,-for example the collar portion 4|] andthe lower flange 45 of the lower fuse terminal or collar I6, see Figure 5, andthe arc is drawn into the tubeand is immediatelyflextinguished by the expulsion action produced. It'is to be noted that the outwardrocking of the lower end of the fuse tube when man ually manipulated as indicated in Figure 2 is .per-

.mitteddue to the fact that the pivot pins-2ll are necessary'to pull the composite fuse link, down wardly by a pull on the manipulating rod and to thereafter detach'ably' lock the lower end of the composite fuse linkto the lever 23 as previously described. The fuse tube may then be replaced and rocked back into circuit-when it is desired to again closethecircuit'." W

In the form of the inventionshown. in Figure 6, the are strikes from. the lower end of the sleeve to the adjacent portion of the rod 31 The purpose of the lower flange 45 is to insure the striking of the are directly from the sleeve ['5 to the adjacent portion of the rod 31, for example the collar 40, and thus insure that the arc will not strike from the lower end of the sleeve Hi to the forked end 21 of the lever 23.

In the form of the invention shown in Figure '7, the same general construction of fuse tube I2 and. associated parts. is employed. The metallic collar 41 corresponding to the collar l6 at the lower end of the fuse tube is not provided with the outer manipulating eyelet IT, as in the first form of the invention. It is provided with the rearwardly extending arm- 48 which is equipped with pivot pins 49 and with a manipulating eyelet portion 50. The arm 4|! is pivoted to the lever 5-lwhich carries the trunnions 52" and whose left-hand portion is constructed in the same mannor as that described in connection with Figure 1. The lever 5| may also be provided with an upwardly extending arm 5| corresponding tothe; arm 23 of Figure 1. The lever 5|, however, is provided with a notched outer end,- the notch being indicated at 52 in Figure 8. This notched end extends less than half way across the? lower collar 42 of the rod 31' and consequently the lever 5| would not of itself restrain the upward motion of the rod. However, a latching member in the form of a lever indicated generally at 53 is pivotally mounted asindicated at 54 on the lever 5| and is provided with a manipulating eyeletu55 adapted to be engaged by a switch stick, The latching member 53 is also provided with a notched portion indicated at 56 in Figure 8 which coacts. with the notched portion 52 of the lever 5| torestrain the collar 42' and consequently the rod: 31. In this, form of the invention there is noineed. for a centering collar like the collar 45- of Figure 5 as the notches 52 and 55 center the fuse link. The lever or latching member 53 is bifurcated. and; is, provided with shouldered portions 51, see Figure '7, which abut the lower surface of the lever 5| andlimit the upward rocking motion of the=latching lever 53. The downward rocking motion ofthe latching lever is limited by meansof the extensions 58 which abut the lower surface of the lever 5| when the latching lever is; in its, downor dotted line position as shown in Figure '1.

The, operation of this form of the invention on overload-is identically the same as that previously described. Themanual operation is slightly different and. consists-in the fact that the latching lever 53 is first drawn downwardly by means of a switch stick. There is sufficient play between the, reduced portion 4| of the rod 31' and the notchedportions of the lovers 5| and 53 to allow the-lever 53 to be pulled downwardly. When it is pulleddownwardly, the collar 42 of the rod 31 is released and-the rod is drawn upwardly into nipulating rod can, be employed. If the manipulating rodispermanently attached, it is made of insulating material. If the manipulating rod is detachable, it may be made of either. metal or mlattutmaterial.

If the cut-out device is caused. to operate by manual manipulation in either form of the. invention, the composite fuse link may be pulled downwardly for reengagement by means of the manipulating rod after the fuse tube has been removed from its supports. It is obviousthat if the manipulating rod. is detachable, it may be inserted through the lower end of. the fuse tube and may be engaged in the lower collar portion 42' of the rod 3 1' and thereafter the composite fuse link may be pulled downwardly for rcengagement.

It is to be'noted that inrocking the cut-out to closed position, the upper terminal of the fuse tube rides beneath the slanting surface 1 until the cap M of the upper contact of the fuse tubeseats within the recessed portion 8 of the upper stationary contact 3. There is sufficient yield provided by the spring 3|, see Figure 5, to allow a slight downward motion of the fuse tube and the associated lever construction at its lower end to allow for this motion.

It is to be understood that the fuse unit consisting of the members 33, 35, 36 and 37 is a renewable unit so that when one fuse unit blows, another may be substituted. It is to be understood also that the composite structure, extending through the fuse tube constitutes in reality a fuse link normally electrically connecting the upper and lower stationary terminals.

It will be seen that a novel form of cut-out has been provided which has both automatic and manual operation responding to an overload in an" automatic manner and capable of being operated manually to interrupt the circuit under load without damage to the cut-out. It is also to -be seen that the composite fuse link is not destroyed when the cut-out is manually opened under load as the same composite fuse link is again put in service as described hereinabove.

It will be seen further that the construction though'affording both of these modes of operation is relatively simple and is not much more complicated than the usual type of drop-out expulsion fuse.

Although this invention has been described in considerable detail, it is to be understood that such description is intended as illustrative rather than limiting, as the invention may be variously embodied and is to be interpreted as claimed.

We claim:

1. A fuse device comprising a fuse tube having an open end, a fuse link within said fuse tube adapted to rupture on overload, stationary contacts normally connected to form a circuit through said fuse link, said fuse link having a projecting portion projecting outwardly from the open end of said fuse tube, retracting means tending to withdraw said projecting portion into said fuse tube, restraining means detachably engaging the projecting portion of said fuse link and restraining the said projecting portion, and manually operable means for causing release of said fuse link from said restraining means whereby the circuit will be interruptedwithin said fuse tube.

2. A fuse device, comprising a fuse tube having an open end, a fuse link within said fuse tube adaptedto rupture on overload, stationary contacts normally connected to form a circuit through said fuse link, said fuse link having a projecting portion projecting outwardly from the open end of said. fuse tube, retracting means tending to Withdraw said projecting portion into said fuse tube'*,.restraining means 'detachably' engaging the projecting 1 portion. of.- said-fuse link: and restrain-eing the said projecting portion. and manually operable means for causing relative motion between said restraining means and said fuse tube to release the projecting portion of said fuse link from said restraining means whereby the circuit will be interrupted within said fuse tube.

3. A cut-out construction comprising a fuse tube having an open end, a fuse link within said fuse tube having a portion projecting outwardly from the open end of said tube, stationary contacts normally connected to form a circuit through said fuse link, said fuse link including a fusible portion operable on electrical overload to interrupt the circuit within said tube: retracting means tending to draw the projecting portion of said fuse link into said tube, restraining means adjacent the open end of said fuse tube for detachably holding the fuse link against motion, and manually operable means for releasing said fuse link from said restraining means, whereby said retracting means will be free to operate and the circuit will be interrupted within said fuse tube,

4. A cut-out construction comprising a fuse tube having an open end, a fuse link within said fuse tube having a portion projecting outwardly from the open end of said tube, stationary contacts normally connected to form a circuit through said fuse link, said fuse link including a fusible portion operable on electrical overload to interrupt the circuit within said tube, retracting means tending to draw the projecting portion of said fuse link into said tube,'restraining means adjacent the open end of said fuse tube for detachably holding the fuse link against motion, and manually operable means for releasing said fuse link from said restraining means, whereby said retracting means will be free to operate and the circuit will be interrupted within said fuse tube, said fuse link being undamaged whe manual operation takes place. i

5. A drop-out cut-out construction comprising a fuse tube having an open end, a fuse link within said fuse tube having a portion projecting outwardly from the open end of said fuse tube, stationary contacts normally connected to form a circuit through said fuse'link, said fuse link including a fusible portion operable on electrical overload to interrupt the circuit within said fuse tube, retracting means tending to withdraw the projecting portion of said fuse link into said fuse tube, restraining means adjacent the open end of said fuse tube for detachably holding said fuse link against motion and being itself restrained by said fuse link, said restraining means normally holding said fuse tube against drop-out motion and releasing said fuse tube for drop-out motion when said restraining means is free of restraint from said fuse link, and manually oper-, able means for releasing saidfuse link from said restraining means.

6. A drop-out cut-out construction comprising a fuse tube having an open end, a fuse link within said fuse tube having a portion projecting outwardly from the open end of said fuse tube, stationary contacts normally connected to form a circuit through said fuse link, said fuse link including a fusible portion operable on electrical overload to interrupt the circuit within said fuse tube, retracting means tending to withdraw the projecting portion of said fuse link into said fuse tube, restraining means adjacent the open end of said fuse tube for detachably holding said fuse link against motion and being itself restrained by said fuse link, said restraining means norma1- ly holding said fuse tube-against drop-out mo: tion and releasing said fuse tube for drop-out motion when said restraining means is free of restraint from said fuse link, and manually opera able means for releasing said fuse link from s'aijd restraining means, the projecting portion ofsai'd 'fuse link when released from said restraining means being drawn into said fuse tube to rupt the circuit within said fuse tube. e

'7. A fuse device comprising a fuse tube having an open end, a fuse link within said fuse tube adapted to rupture on overload, stationary'con tacts normally connected to form a circuit through said fuse link, said fuse link having a projecting portion projecting outwardly from the open end of said fuse tube, retracting means tending to withdraw said projecting portion into said fuse tube, restraining means detachably-engaging the projecting portion of said fuse link and restraining the said projecting portion, and means having a portion operable externally of said fuse tube and adapted to receive a switch stick for releasing the projecting portion of said inter fuse link from said restraining means for breaking the connection between said stationary contacts within said fuse tube independently of load conditions. v

8. A fuse device comprising a movably mounted fuse tube having an open end, a fuse link within said fuse tube adapted to rupture on overload, stationary contacts normally connectedto form a circuitthrough said fuse link, said fus'e' jlink having a projecting portion projecting outward ly from the open end of said fuse tube, retracting means tending to withdraw said projecting por tion into said fuse tube, restraining means detachably engaging the projecting portion of said fuse link and restraining the said projecting portion, and manuall operable means engageable by a switch stick for moving said fuse tube with reference to said restrainingmeans to release the projecting portion of said fuse link from restraining means.

9. A fuse device comprising a fuse tube having an open end, a fuse link within said fuse tube adapted to rupture on overload, stationary contacts normally connected to form a circuit through said fuse link, said fuse link having a projecting portion projecting outwardly from the open end of said fuse tube, retracting 'Ineans tending to withdraw said projecting portion into said fuse tube, movable restraining means detachably engaging the projecting portion of said fuse link and restraining the said projecting portion, and manually operable means for moving said movable restraining means to detach said restraining means from said fuse link. I

10. A fuse device comprising a fuse tube hav: ing an open end, a fuse link within said fuse tube adapted to rupture on overload, stationary contacts normally connected to form a circuit through said fuse link, said fuse link-having a projecting portion provided with an enlargement normall located beyond the open end-of said fuse tube, yieldable retracting means tending to withdraw the projecting portion of said fuse link into said fuse tube, restraining means having a notched portion detachab-ly engaging the enlargement of said fuse link and restraining the pro jecting portion of said fuse link from retraction into said fuse tube, and manually operable means for causing detachment of said enlargement from the'said notched portion of said"re-' straining means.

11. A fuse device comprising a fuse tube havsaid ing an open end, a fuse link within said fuse tube adapted to rupture on overload, stationary contacts normall connected to form a circuit through said fusev link, said fuse link having a projecting portion projecting outwardly from the open end of said fuse tube, retracting means tending to withdraw said projecting portion into said fuse tube, restraining means detachably en gaging the projecting portion of said fuse link and restraining the said projecting portion, manually operable means for causing release of said fuse link from said restraining means whereby the circuit will be interrupted within said fuse tube, and a second manually operable means attached to the end of said fuse link for drawing said fuse link outwardly from the open end of said fuse tube after manual operation of the device.

12. A fuse device comprising a fuse tube having an open end, a fuse link within said fuse tube adapted to rupture on overload, stationary contacts normally connected to form a circuit through said fuse link, said fuse link having a projecting portion projecting outwardly fromlthe open end of said fuse tube, retracting means tending to withdraw said projecting portion into said fuse tube, restraining means detachably engaging the projecting portion of said fuse link and restraining the said projecting portion, and manually operable means for causing release of said fuse link from said restraining means whereby the circuit will be interrupted within said fuse tube, the end of said fuse link havin means for detachably receiving a withdrawing instrumentality whereby the end of said fuse link may be drawn outwardly from the open end of said fuse tube after manual operation of the device.

13. A fuse device comprising an expulsion fuse tube having an open end, a fuse link within said fuse tube adapted to rupture on overload, stationary contacts normally connected to form a circuit through said fuse link, said fuse link when ruptured on overload interrupting the circuit within said fuse tube, said fuse link having a projecting portion projecting outwardly from the open end of said fuse tube, retracting means tending to withdraw said projecting portion into said fuse tube, restraining means detachably engaging the projecting portion of said fuse link and restraining the said projecting portion, and manually operable means for causing release of said fuse link from said restraining means whereby the circuit will be interrupted within said fuse tube upon manual release, said device having an expulsion action when interruption occurs either by rupture of the fuse link on overload or by operation of said manual means.

14. A drop-out fuse device comprising a pair of stationary contacts, a fuse tube having an open end, a fuse link within said fuse tube, said fuse link having a projecting portion projecting from the open end of said fuse tube, said fuse tube normally occupying an operative position and biased towards drop-out motion to an inoperative position, retracting means tending to retract the projecting portion of said fuse link into said fuse tube, mechanism normally holding said fuse tube in operative position and including restraining means releasably holding the projecting portion of said fuse link, and manually operable means for causing release of said fuse link from said restraining means, said mechanism releasing said fuse tube for drop-out operation when said fuse link is ruptured on overload or when said fuse link is detached from said restraining means.

15. A drop-out fuse device comprising an up per and a lower stationary contact, said upper contact having a rigid latch portion, a fuse tube having an open lower end and a closed upper end, the upper end of said fuse tube normally having interlocking engagement with the rigid latch portion of said upper stationary contact, a fuse link within said fuse tube extending outwardly from the lower open end thereof, and a lever pivotally supported from said lower contact and controlled by said fuse link for normally holding said fuse tube in operative position and releasable upon overload to release the upper end of said fuse tube from engagement with the rigid latch portion of said upper stationary contact, said fuse link including a resilient portion intermediate its ends to allow the said lever to move with reference to said fuse tube when said fuse tube is rocked into latching engagement with the rigid latch por tion of said upper stationary contact.

16. A drop-out fuse device comprising an upper and a lower stationary contact, a fuse tube having a closed upper end normally detachably interlocked with said upper station-ary contact and having an open lower end, a fuse link within said fuse tube including an intermediate resilient portion and a port-ion projecting outwardly from the lower open end of said fuse tube, a lever pivotally supported from the lower contact and having means interengaging with the projecting portion of said fuse link for restraining said fuse link, said lever normally holding said fuse tube in operative position and releasable upon the occurrence of an overload, and means adapted to be engaged by a switch stick for detaching the projecting portion of said fuse link from said lever, the projecting portion of said fuse link when detached from said lever being retracted into said fuse tube by the resilient portion of said fuse link.

17. A fuse device comprising a fuse tube having an open lower end and having a closed upper end, a fuse link within said fuse tube, stationary contacts normally connected to form a circuit through said fuse link, said fuse link having a fusible portion adjacent the lower open end of said fuse tube and located within said fuse tube for interrupting the circuit within said fuse tube on electrical overload, said fuse link having a pro jecting portion projecting outwardly from the open end of said fuse tube, resilient contractlble retracting means located within said fuse tube above said fusible portion and tending to withdraw said projecting portion into said fuse tube, restraining means detachably engaging the projecting portion of said fuse link and restraini the said projecting portion, and manually operable means for causing release of said fuse link from said restraining means whereby the circuit will be interrupted within said fuse tube on manual release.

WILLIAM 0. SCHULTZ. ALWIN G. STEINMAYER.

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