US2269130A - Fuse - Google Patents

Description

Jan. 6, 19 42. w. o. SCHULTZ FUSE 4 Sheets-Sheet 1 Filed Dec. 4, 1939 INVENTOR. I V/JA/AM 0. 30/1/01 Jan. 6, 1942.

W. O. SCHULTZ FUSE Filed Dec. 4, 1939 4 Sheets-Sheet 2 INVENTOR.

W\ ATTORNEY.

w. o. SCHULTZ 2,269,130

' FUSE Filed Dec. 4, 1959 4 Sheets-Sheet 4 f1 I 1 I w 4 2 I W v j] if INVENTOR.

14/41/444 0. SCf/l/ZTZ ATTO/PIYEK Patented Jan. 6, 1942 FUSE William 0. Schultz, South Milwaukee, Wis., assignor to Line Material Company, South Milwaukee, Wis., a corporation of Delaware Application December 4, 1939, Serial No. 307,350

(Cl. 200l14) 16 Claims.

dragging over the-end of the fuse tube and also permitting the use of relatively still ,fuse link leaders if so desired.

In greater detail, further objects are to pro vide a fuse link flip-out device and a fuse tube releasing device which is so made that it quickly and forcibly withdraws the unburned portion of the fuse link, thereby securing a quick interruption of the circuit within the fuse tube itself, which thereafter releases the fuse tube and allows the fuse tube to drop or rock outwardly from operative to inoperative position.

Further objects are to provide a fuse construction in which a quick operating fuse link flip-out device is provided for quickly withdrawing any remaining portion of the fuse link, and to so construct the fuse link flip-out device that it has very little weight and may be quickly operated by spring means independent of any motion of any of the other portions of the apparatus.

Further objects are to provide a construction in which the fuse link flip-out device acts as a spring cushioning means for taking up any slack in the fuse link after re-fusing, and which acts asa cushioning member when the fuse device is suddenly rocked back into closed position, thereby preventing transmission of any undue stress to the fuse link itself.

Further objects are to provide a drop-out fuse construction which may be either housed or unhoused, in which the fuse tube is pivotally mounted on a supporting lever, the supporting lever in turn being pivotally mounted on a stationary support; and in which the fuse link flipout device is pivotally mounted on the supporting lever, the fuse link flip-out device being spring biased with respect to the lever and hav ing motion independent of the lever and being of relatively light weight so that a very quick acting device is provided. and to provide a construction in which the supporting lever may be freely removed from or repositioned within the lower supporting means without any hindrance from the fuse link flip-out device.

Embodiments of the invention are shown in the accompanying drawings, in which:

Figure 1 is a side elevation showing the invention as applied to a drop-out unhoused fuse.

Figure 2 is a fragmentary view of the lower portion of Figure 1, showing in full lines the position of the parts after the fuse link has ruptured and the fuse tube has moved part of the way outwardly and downwardly and showing in broken lines the final position of the fuse tube.

Figure 3 is an enlarged view of the fuse tube removed from the rest of the apparatus, such view having parts broken away and in section.

Figure 4 is a view of the lower portion of Figure 3 taken at right angles thereto.

Figure 5 is a bottom view of the structure shown in Figure 3.

Figure 6 is a vertical sectional view showing the invention as applied to a housed type of drop-out fuse.

Figure 7 is a view showing the housed type of drop-out fuse mounted in an angular position.

Figure 8 is a fragmentary view showing a further form of the invention.

Figure, 9 is a bottom view of the structure shown in Figure 8.

Figure 10 is a fragmentary view showing a still further form of the invention.

Figure 11 is a bottom view of the structure shown in Figure 10.

Referring to Figures 1 to 5, it will be seen that the device comprises a fuse tube I which is mounted between upper and lower terminal members 2 and 3 carried by any suitable support. for instance upper and lower insulators I and I which are in turn carried by a channel member 8. The channel member may be supported from any suitable point in the usual manner. If'desired, the fuse tube may be mounted in the angular position shown or may be mounted vertically.

The fuse tube is provided with an upper contact I having a flat rear face 3 against which a brush contact or spring contact 9 firmly bears, such brush contact forming a portion of the upperterminal member.

The upper contact of the fuse tube includes a cap it which is screwed on the portion I and clamps the buttonhead of the fuse link in place,

as shown most clearly in Figure 3. The cap It is provided with an integral hind a shouldered portion member l2. indicated at pin II which fits beof a pivoted latch The latch member is pivoted, as It, to the upper terminal member and is of hood-like construction, shielding the upper contact of the fuse tube and the brush contact and acting in the manner of a sleet hood.

It is provided with a cam poi tion l4 so as to raise it when the fuse tube is being rocked back into position. The shouldered portion |5 drops downwardly in front of the pin II when the fuse tube is in its final position. The sleet hood or upper latch |2 may be provided with a stop |6 to limit its downward rocking motion.

It is obvious that other forms of contacts could be employed and other forms of latching means without departing from the spirit of this invention. Any of the usual forms well known in the art could be employed.

Means are provided for releasing the latch member manually if so desired, and may comprise an eyelet portion |1 adapted to receive a switch stick and pivoted at H! upon upper contact 1. This releasing member is provided with a pair of arms l9 located on opposite sides of the contact 1 and directly beneath the sleet hood or upper latch |2 so that when the eyelet member is pulled downwardly, it raises the latch and releases the fuse and allows the fuse tube to be swung outwardly.

The lower terminal member 3 includes a brush contact or spring contact which is secured to a web portion 2| extending between and supported by the side portions 22 of the lower member 3. These side portions 22 are'provided with hook like portions 23 for supporting the trunnions of the fuse structure. They are also provided with downwardly extending abutments or stops 24 adapted to engage the bumpers of the fuse tube, as will hereinafter appear.

A metal collar or member 25 is securely attached to the fuse tube adjacent its lower portion and may be provided with a manipulating member 26 adapted to be received by a switch stick in the usual manner for replacing the fuse in its trunnions after re-fusing.

The collar 25 pivotally supports a lever 21 which is provided with arms on opposite sides hinged .to the member 25 as indicated at 28. The lever 21 is provided with a fiat rear face 29 against which the brush contact 20 securely bears. The lower portion of the lever 21 is bifurcated as indicated at 30, see particularly Figure 4, and is provided with a pair of trunnions 3| projecting from opposite sides.

The lever 21 is also provided with a pair of rubber bumpers 32 located on opposite sides thereof intermediate the ends of the lever and carried by outwardly projecting pins 33 rigid with the lever.

The trunnions 3| are removably received within the hook like supports 23, as shown in Figures 1 and 2, and may be readily detached therefrom when it is desired to remove the fuse tube for re-fusing, for instance.

A flip-out or fuse link extracting device, which may take the form of an auxiliary lever 34 see particularly Figure 3, is pivotally mounted between-the arms 3|] as by means ofa pin 35. A spring 36 is provided and loosely coiled about the pin and bears against the lever 21 and against the flip-out device or auxiliary lever 34, thus urging the flip-out device 34 in a clockwise direction, as viewed in Figure 3. The flip-out device 34 may be of channel shape and is of relatively light weight. It is provided with an upturned forward end 31 and an upturned rear end 38.

The fuse link is looped over the flip-out device. For example the fuse link may comprise the upper buttonhead 39, the fusible section 46, and the flexible leader section 4|. The flexible leader extends out of the open lower end of the fuse tube and over the flip-out device 34. It is clamped to the lever 21 by means of the thumb nut 42, such thumbnut being/carried on a threaded pin rigid with the lever, as shown particularly in Figures 3 and 4.

It is to be noted particularly from reference to Figures 3 and 4 that the lever 34 has rearwardly projecting side portions 43 which are adapted to engage a projection or web 44 formed on the lever 21 to thus limit the outward rocking motion of the flip-out device 34 when released upon rupture' of the fuse link. Further,

the rearwardly projecting portions 43 serve as guides between which the fuse link is passed so that the fuse link may be led to the side of the lever 21 and clamped beneath the thumb nut 42, as shown most clearly in Figure 4.

The operation of the apparatus is as follows: Upon rupture of the fuse link, the flip-out device immediately operates and withdraws any remaining portion of the fuse link substantially directly downwardly in line with the fuse tube.

This flip-out device operates very quickly as it has little mass and is spring urged to extract any remaining portion of the fuse link, and also as it operates independently of any motion of the lever 21 and fuse tube I, so that these relatively more massive parts do not have to move before the flip-out device operates and thus a very quick interruption of the circuit within the fuse tube is obtained even on light overloads. Obviously, on heavier overloads, the expulsion action is pronounced in addition to the withdrawal of any remaining portion of the fuse link by the flip-out device.

When the fuse link is ruptured, it is clear from an inspection of Figure 1 that the lever 21 is also released and free to move with respect to the fuse tube, thereby allowing the lower end of the fuse tube to move outwardly and downwardly and thus lowering the upper pin II and allowing it to pass from engagement with the shouldered portion l5 of the upper latch |2. The fuse tube has been shown in successive positions in Figure 2. It is apparent that when the fuse tube rocks to its final position, that the rubber bumpers or cushioning bumpers 32 will engage the stops'or abutments 24 of the lower support and will cushion thefall of the fuse tube.

The sequence of operations, it will be noted, is as follows:

First, upon rupture of the fuse link the flip-out device quickly operates and withdraws any remaining portion of the fuse link independently of any motion of the fuse tube or of the supporting lever 21. Thereafter the fuse tuberocks outwardly and bodily removes itself from the electric circuit.

When it is desired to re-fuse the device, the

lineman engages the member 26 by means of a switch stick and lifts the fuse tube from the support, detaching the trunnions 3| from the hooks 23. Thereafter a new fuse link is inserted in the fuse tube and drawn securely over the flip-out device 34 and clamped by means of the thumb nut 42. 'Any slack is taken up by means of the spring urged flip-out device 34.

The lineman repositions the trunnions 3| within the hooks 23 and thereafter disengages the switch stick from the member 26 and hooks the switch stick into the eyelet portion l1 and rocks the fuse back into its operative position. The fuse link is not subjected to undue stress or shock due to the'sudden rocking of the fuse tube back motion by the downward into operative position, for the spring pressed flip-out device 84 serves to .cushion any shock due to this cause and to prevent its transmission to the fuse link.

The fuse tube is biasedtowards open position by gravity and also by the outward pressure of the spring contacts of the upper and lower terminal members, and also biased towards outward pressure from the uppe latch H which may be urged downwardly either by gravity, as shown, or by means of a spring.

It will also be seen that the flip-out device will operate without any hindrance from other portions of the apparatus and independently of any motion of any of the other portions of the apparatus. Thereafter, as hereinabove described, the fuse tube rocks outwardly to inoperative position.

It will thus be seen that the invention provides for the quick interruption of the circuit within the fuse tube prior to the'parting of either the upper or lower stationary contacts with the upper and lower contacts of the fuse tlf'Je. The upper and lower stationary spring contacts follow the contacts of the fuse tube outwardly a predetermined distance after the fiip-out device has operated and thus pitting of the contacts due to arcing is avoided, as the circuit is completely interrupted within the fuse tube prior to the moving of the contacts of the fuse tube away from the brush contacts.

It is to be noted also that the lower brush contact bears against the lever 21 at a point spaced upwardly a material distance from the flip-out device, and that attached directly to the flip-out device but is merely looped over-the flip-out device as shown.

In the form of the invention shown in Figures 6 and 7, a housed type of drop-out fuse is employed. The housing may be of porcelain or other suitable material and is provided with a door 46 of insulating material, such as a phenolic condensation compound. If desired, the door may have the usual eyelet so that the door and fuse tube assembly may be manually pulled outwardly if desired.

The housing itself constitutes the supporting means for the upper and lower terminal members 41 and 48 and these upper and lower terminal members include the brush contacts 49 and 56. The upper terminal member is also provided with a pair of spring arms 5i between which the upper contact 52 of the fuse tube 53 is normally positioned. These spring arms have slanting portions 54 which are positioned in front of projecting pins 55 rigid with the upper contact 52, and thus serve as latching means for retaining the fuse tube and door assembly normally in closed position, such assembly dropping to open positionupon rupture of the fuse link as will hereinafter appear.

The fuse tube is provided with the upper cap 55 for clamping the buttonhead of the fuse link in place as hereinbefore described. Preferably the upper contact 52 is provided with a spacing finger or bearing finger 51 that bears against the inner face of the door. The upper portion of the door carries a pair of spring arms 56 between which the upper contact 52 of the fuse tube is received. These spring arms have an outwardly projecting cam portion indicated generally at 59 so that when the door is manually pulled open, it will spread the arms 5| and allow the pins 55 to pass between such spring arms II. Further, in closing the door, the cam porthe fuse link is not tions 59 of the spring fingers ll spread the arms II and allow the pins 55 to pass inwardly to a position behind the spring arms ll. such arms thereafter moving inwardly towards each other and engaging the pins 55. This construction is described in greater detail in Patent No. 2,073,186 of Alwin G. Steinmayer and-William 0. Schultz, issued March 9. 1937, for Housed type of dropout fuse.

The fuse tube 58 carries a collar 56 rigidly secured thereto in any suitable and the collar is pivoted to a pair of arms 6| carried by the door. The pivoting is secured by means ofthe pins or screws 62 which also serve to pivot the lever 81 to the collar 50.

- A leaf spring 64 bears against the lower portion of the fuse tube and tends to rock the fuse tube about the pivot 62 and to hold the finger 51 in contact with the upper inner side of the door, as shown in Figure 6. When the door is manually pulled open, there is relative rocking motion between the fuse tube and the door to allow the cam portions 55 of the spreader fingers 58 to spread the spring members 5| to allow the which is manner v door and fuse tube assembly to be manually pulled open.

The lever 63 is provided with a pair of side arms 65 equipped with trunnions 66 which are removably received within the hook supports 51. The hook supports are distinct and separate from the lower contact, as shown in Figure 6, and are carried by the body portion 45. They are provided with inwardly projecting portions 6! which constitute stops and also about which hooked extensions 69 of thelever 63 pass to prevent the trunnions 66 from being inadvertently detached from the hook supports 61 when the fuse tube and door assembly has dropped to open position.

If desired, and as shown in Figure 6, the lever 63 may be of channel shape andprovides a fiat rear face 10 against which the lower brush contact 50 bears. This lever is also provided with a threaded stem upon which the lock nut II is screwed to clamp the leader 12 of the fuse link in place.

A flip-out or fuse link extracting device which may take the form of an auxiliary lever II is pivotally mounted as indicated at 14 between the side arms 65 of the lever 63 and is spring urged in a clockwise direction by means of the spring 15. turned forward and rear ends, as shown and as previously described, and with the side portions or extensions I5. These extensions are adapted to engage a transverse web 11 formed on the lever 63 and thus limit outward rocking motion of the flip-out device.

When the fuse link ruptures upon overload, the flip-out device first quickly operates and withdraws any remaining portion of the fuse link substantially directly downwardly in line with the fuse tube. Thereafter the fuse tube and door assembly rock outwardly, the lever 58 pivoting in the hook-shaped members 61 and moving the lower end of the fuse tube and door assembly downwardly and outwardly, thus allowing the upper pins 55 to slide outwardly from the slanting portions 54 of the spring arms II.

It will be seen that the housing itself in this last form of the invention constitutes the support for the upper and lower terminals and for the fuse tube and door assembly. Also it will be seen that the hook supports 61 are electrically dead after the fuse tube and door assembly have dropped outwardly from the housing.

It may be provided with upwardly ing aconstruction having Further it is to be noted that the quick action of the fiipout device serves to quickly extract any remaining portion of the fuse link and to thus quickly interrupt the circuit within the fuse tube prior to separation of either the upper or lower contact of the fuse tube from the stationary contacts and thus prevents'pitting.

The fuse tube and door assembly may be detached from the hook supports ti and the device may be re-fused and thereafter replaced. The trunnions are repositioned within the hook supports bl and the fuse tube and door assembly are rocked back into position. 7

It is to he noted the flip-out device l3 serves to take up any slack in the fuse link and also to cosluon any due to the sudden closing of the device It is obvious that device may be mounted either verticall; as shown in Figure 6, or in the slanting position as shown in Figure '3.

it will be seen that novel forms of expulsion drop-out fuses have been provided by this invention in which iiip cut device is employed which has motion idependently of the supporting lever and aui withdraws any remaining portion of the e 1k upon rupture of the fuse link substantially in line with the fuse tube. This, as previously described, allows the use of less flexible leaders if so desired.

The flip-out device operates independently of any acceleration that may be imparted to the relatively more massive moving parts of the device andthue insures a very quick action and a complete extinguishing of the are within the fuse tube prior to the parting oi the contacts of the fuse tube from the stationary contacts.

In each of the forms of the invention, the fuse link has been shown as looped over the flip-out device and the attaching means for the fuse link has been shown as carried by the supporting lever. This is the most desirable construction as it makes for ease in re-fusing and as it allows the mass of the flip-out device to be kept at a minimum.

However, it is within the province of this invention to thread the fuse link throughia hole in the flip-out device 36 as shownin Figures 8 and 9. Under these conditions, it is clear that a portion of the fuse link would necessarily be looped over the flip-out device, thereby providthe same characteristics as that illustrated in so far as a portion of the fuse link would be looped over a part of the flip-out device to thereby cause the flip-out device to bear against the fuse link and extract the fuse link as it does in the illustrated forms. A little more dificulty would be experienced in positioning the fuse link and this, therefore, is not the preferred form of construction. 7

Additionally, in any form of the invention, the locking thumb nut 32 for the fuse link could be carried directly by the flip-out device 35" as shown in Figures 10 and 11, but this obviously is not as desirable a construction as that illustrated. It would increase the mass of the flipout device and also there would not be the direct electrical connection between the fuse link and the lever, which constitutes one of the terminals of the device and bears directly against the lower brush'contact. However, these constructions are obviously within the scope of this invention and can be resorted to if so desired without departing from the spirit of the invention.

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

I claim:

1. A drop-out fuse construction comprising upperland lower stationary terminals, a fuse tube having an upper end detachably locked to said upper stationary terminal, a lever supporting said fuse tube for drop-out motion, said lever being pivoted at one end to said fuse tube and pivotally supported at its other end, said upper and lower terminals including upper and lower stationary contacts, a fuse link within said'fuse tube electrically connecting said upper and lower contacts and normally restraining said lever against motion, and a fuse link flip-out device movably carried by said lever and over which said fuse link is looped.

2. A drop-out fuse construction comprising upper and lower stationary terminals, a fuse tube having an upper end detachably locked to said I upper stationary terminal, a lever supporting said fuse tube for drop-out motion, said lever being pivoted at one end to said fusetube and pivotally supported at its other end, said upper and lower terminals including upper and lower stationary contacts, a fuse link within said fuse tube electrically connecting said upper and lower contacts and normally restraining said lever against motion, a fuse link flip-out device movably carried by said lever and over which said fuse link is looped, and a spring biasing said flipout device for movement independently of said lever.

3. A drop-out fuse construction comprising upper and lower stationary terminals, a fuse tube having an upper contact normally engaging said upper stationary terminal and detachably interlocking therewith, a lever supporting said fuse tube for drop-out motion, said lever having one end pivoted to said fuse tube and having its other end plvotally supported, a fuse link within said fuse tube extending from the upper contact of said fuse tube to said lever and normally restraining said lever against motion, a. fuse link flip-out device carried by said lever and having motion independently of said lever, said fuse link being looped over said flip-out device, and means biasing said flip-out device for quick motion.

4. A drop-out fuse construction comprising upper and'lower stationary terminals, a fuse tube having an upper contact normally engaging said upper stationary terminal and detachably interlocking therewith, a lever supporting said fuse tube for drop-out motion, said lever having one end pivoted to said fuse tube and having its other end pivotally supported, said lower stationary terminal including yielding contact means bearing against said lever, a fuse link within said fuse tube extending from the upper i contact of said fuse tube to said lever and normally restraining said lever against motion, a fuse link flip-out device carried by said lever and having motion independently of said lever, said fuse link being looped over said flip-out device, and means biasing said flip-out device for quick motion.

5. A drop-out fuse construction comprising upper and lower stationary terminals, said upper stationary terminal including latch means, a fuse tube having an upper contact normally engaging said upper stationary terminal and detachably interlocking with said latch means, a lever supporting said fuse tube for drop-out motion, said lever being pivotally supported adjacent oneend and pivoted adjacent its other end to said fuse tube, a fuse link-within said fuse tube extending from the upper contact of said fusetube to said lever and normally restraining said lever against mo tion, a fuse link flip-out device carried by said lever and having motion independently of said lever, said fuse link being looped over said flipout device, and means biasing said flip-out device for motion independently of said lever.

6. A drop out 'fuse construction comprising 7 support means having upper and lower stationary portions, an upper stationary contact carried by said upper stationary portion, a fuse tube having an upper contactylatch'means carried by said stationary portion and pivoted at its other end I to said fus'e tube for guiding the lower end of said fuse tube downward ly to detach said fuse tube from said latch means, a fuse link extending from the upper contact of'said fuse tube to said' lever and secured to said lever and normally restraining said lever, a fuse link flip-out device movably carried by said lever and over which said fuse link is looped, and a lower stationary contact carried by said lower stationary portion andyieldingly engaging said lever at a point spaced from said fuse link flip-out device.

'7. A drop-out fuse construction comprising a stationary portion, an upper stationary contact carried by said stationary portion, a fuse tube having an upper contact, latch means carried by said stationary portion and detachably engaging the upper end of said fuse-tube and holding the upper contact of said fuse tube in engagement with said upper stationary contact, a normally substantially vertical lever pivotally supported adjacent its lower end from said stationary portion and pivoted adjacent its upper end to said fuse tube for guiding the'lower end of said fuse tube-downwardly andoutwardly to detach said fuse tube from said latch means, a fuse stationary portion, an upper stationary contact link extending from the upper contact of said j fuse tube to said lever, said fuse link being attached to said lever and normally restraining said lever against motion, and a fuse link flip-out device carried by said lever and over which said fuse link is looped.

8. A drop-out fuse construction comprising a stationary portion, an upper stationary contact carried by said stationary portion, a fuse tube having an upper contact, latch means carried by said stationary portion and detachably engaging the upper end of said fuse tube and holding the upper contact of said fuse tube in engagement with said upper stationary contact, a normally substantially vertical lever pivotally supported adjacent its lower end from said stationary portion and pivoted adjacent its upper end to said fuse tube for guiding the lower end of said fuse tube downwardly and outwardly to detach said fuse tube from said latch means, a fuse link extending from the upper contact of said fuse tube to said levei', said fuse link being attached to said lever and normally restraining said lever against motion, a fuse link flip-out device carried by said lever and over which said fuse link is looped, and a lower stationary contact carried by said stationary portion and yieldingly engaging said lever at a point above said fuse link flip-out device.

9. A drop-out fuse construction comprising a having an upper contact, latch means carried by said stationary portion and detachably engaging the upper end of said fuse tube and holding the upper contact of said fuse tube in engagement with said upper stationary contact, a

normally substantially vertical lever pivotally supported adjacent its lower end from said stationary portion and pivoted adjacent its upper end to said fuse tube for guiding the lower end of said fuse tube downwardly and outwardly to detach said fuse tube from said latch means, a

fuse link extending from the upper contact of said fuse tube to said lever, said fuse link being attached to said lever and' normally restraining said lever against motion, a fuse link flip-out device carried by said lever and over which said fuse link is looped, and a lower stationary contact carried by said stationary portion and yieldingly engaging said lever at a point above said fuse link flip-out device, said upper and lower stationary contacts maintaining engagement ,withthe upper contact of said fuse tube and with said lever respectively while said fuse link flip-out device operates, whereby pitting of either contact is avoided. g

10. A drop-out fuse construction comprising a stationary portion having an upper contact,

a fuse tube having an upper contact, latch means carried by said stationary portion for holding the upper contact of said fuse tube in engagement with the upper stationary contact, a substantially vertical lever pivotally supported adjacent its lower end from said supporting means and pivoted adjacent its upper end to said fuse tube for guiding the lower end of said fuse tube outwardly and downwardly to detach-the upper end thereof from said latch means, a lower contact normally engaging said lever, a fuse link flip-out device pivotally mounted on said lever adjacent the lower end thereof and spring urged outwardly for motion independently of said lever, a fuse link within said fuse tub normally electrically connecting the upper contact of said fuse tube with said lever and looped over said fuse link flip-out device, and means carried on the side of said lever for attaching said fuse link to said lever.

11. A drop-out fuse construction comprising a stationary portion having an upper ontact, a fuse tube having an upper contact, latch means carried by said stationary portion for holding the upper contact of said fuse tube in engagement with the upper stationary contact, a substantially vertical lever pivotally supported adjacent its lower end from said supporting means and pivoted adjacent its upper end to said fuse tube for guiding the lower end of said fuse tube outwardly and downwardly to detach the upper end thereof from said latch means, a lower contact normally engaging said lever, a fuse link flip-out device pivotally mounted on said lever adjacent the lower end thereof and spring urged outwardly for motion independently of said lever, a

' fuse link within said fuse tube normally electrically connecting the upper contact of said fuse tube with said leverand looped over said fuse link flip-out device, and means carried on the rear side of said lever for attaching said fuse link to said lever.

12. An open type drop-out fuse construction comprising supporting means, upper and lower insulators carried by said supporting means, upper and lower terminal members carried by saidupper and lower insulators respectively, each of said mally engaging the upper stationary contact,

latch means supported from said upper insulator for locking the upper contact of said fuse tube in engagement with the upper stationary contact,

a substantially vertical lever having laterally projecting trunnions pivotally supported from said lower terminal member and having its upper end pivoted to said fuse tube, a fuse link fiip-out lever pivoted to said first mentioned lever, a spring between said first mentioned lever and said fuse link flip-out lever, and a fuse link extending through said fuse tube from the upper contact of said fuse tube to said first mentioned lever and attached to said first mentioned lever, said fuse link being looped over said fuse link flip-out lever.

13. A housed type drop-out fuse device comprising a housing having upper and lower terminal members provided respectively with upper and lower stationary contacts, a fuse tube having an upper contactnormally in engagement with said upper stationary contact, latch means for latching the upper contact of said fuse tube in engagement with said upper stationary contact, pivot support means spaced downwardly below said lower terminal member, a lever pivoted to said pivot support means adjacent the lower end of the lever and pivoted to said fuse tube adjacent the upper end of said lever, said lever being normally in contact with the lower stationary contact, a fuse link flip-out lever pivotally carried adjacent the lower portion of said first mentioned lever, a spring urging said fuse link flip-out lever towards motion independently of said first mentioned lever, and a fuse link within said fuse tube extending from the upper contact of said fuse tube to said first mentioned lever and secured to said first mentioned lever, said fuse link being looped over said fuse link flip-out ever.

14. A drop-out fuse construction comprisingupper and lower stationary terminals, a fuse tube having an upper end detachably locked to said trically connecting said upper and lower contacts and normally restraining said lever against motion, and a fuse link flip-out device movably carried by the lever and engaging 'a portion of the fuse link to withdraw the fuse link upon rupture thereof.

15. A drop-out fuse construction comprising upper and lower stationary terminals, a fuse tube having an upper end detachably locked to said upper stationary terminal, a lever, supporting said fuse tube for drop-out motion, said lever being pivoted at one end to said fuse tube and pivotally supported at its other end, said upper and lower terminals including upper and lower stationary contacts, a fuse link within said fuse tube electrically connecting said upper and lower contacts and normally restraining said lever against motion, a fuse link flip-out device movably carried by the lever and engaging. a portion of the fuse link to withdraw the fuse link upon rupture thereof, and a spring biasing said fiipout device for movement independently of said lever.

16. A drop-out fuse construction comprising support means having upper and lower stationary portions, an upper stationary contact carried by said upper stationary portion, a fuse tube having an'upper contact, latch means carried by said upper stationary portion and detachably engaging the upper end of said fuse tube and normally holding the upper contact of said fuse tube in engagement with the upper stationary contact, a lever pivotally supported at one end from said stationary portion and pivoted at its other end to said fuse tube for guiding the lower end of said fuse tube downwardly to detach said fuse tube from said latch means, a fuse link within said fuse tube electrically connecting the upper contact of said fuse tube to said lever, a fuse link flip-out device movably carried by said lever and engaging said fuse link, and a lower stationary contact carried by said lower stationary portion and yleldingly engaging said lever at a point spaced from said fuse link flip-out device.

WILLIAM O. SCHULTZ.

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