US1979418A

US1979418A - Fuse

Info

Publication number: US1979418A
Application number: US638676A
Authority: US
Inventors: Alwin G Steinmayer; William D Kyle
Original assignee: Line Material Co
Current assignee: Line Material Co
Priority date: 1932-10-20
Filing date: 1932-10-20
Publication date: 1934-11-06
Anticipated expiration: 1951-11-06

Description

Nov. 6, 1934. A. G. STEINMAYER Er Al.

FUSE

Filed oct. 20, 1932 (Ittorneg df/m k VZ 1w Patented Nov. 6, 1934 UNTED STATES PlirENr orrics waukee, Wis., assignors to Line Material Company, South Milwaukee, Wis., a corporation of Delaware Application October 20, 1932, Serial No. 638,676

Claims.

This invention relates to fuses and is particularly directed to an expulsion type of fuse.

In expulsion type fuses where the fuse cartridge is housed with the open end of the cartridge ad- 5 jacent the lower portion of the housing, it has been found diicult to prevent gases entering through the lower portion of the housing. These gases are highly conducting and it is very desirable to keep them from entering the housing at the time of the expulsion of the fuse.

Objects of this invention are to provide a novel type of expulsion fuse in which means are provided in the form of abarrier or shield closely adjacent the lower portion of the fuse cartridge and cooperating with the opening in the housing so that the gases are prevented from entering the housing, but instead in which the barrier itself materially reduces the possibility of the reversal of the flow of the gases adjacent the open end of the cartridge, thereby greatly increasing the safe rupturing capacity of the fuse.

In greater detail, further objects of this invention are to provide an expulsion fuse in which the barrier is located very close to the extreme open end of the fuse so that the gases do not have an opportunity to change their direction adjacent this open end, in which there are no slots which provide free access of the gases to the inner portion of the housing adjacent the end of the tube, in which the cartridge is slightly inset with reference to the bottom of the housing so as to house or protect the looped end of the fuse to avoid accidental contact therewith, and in which the bottom of the box or housing substantially encircles the barrier at the end of the fuse tube.

Embodiments of the invention are shown in the accompanying drawing, in` which:

Figure 1 is a longitudinal sectional view through the device, with parts broken away.

Figure 2 is a sectional view on the line 2-2 of Figure 1.

Figure 3 is a fragmentary sectional view of a mcdied form.

Figure 4 is a view corresponding to Figure 3 of a further modied form.

Referring to the drawing, it will be seen that the housing comprises a box l formed of porcelain or other suitable material. This box is provided with a hingedly mounted cover 2 in accordance with the usual construction. The body portion is provided with an intermediate notched barrier 3 within the notch of which the fuse cartridge 4 is positioned when the cover is closed.

cla

(Cl. 20G-127) The fuse cartridge is provided with an upper contact 5 and a lower contact 6, the upper contact being provided with a clamping cap 7 to secure the upper end of the fuse link 8. The lower end of the fuse link is looped around the lower end of the cartridge and around the barrier 9 and secured by clamping means, such as the thumb nut l0, to the lower contact 6.

The cover or door 2 is provided with a looped or eyelet portion 11 into which a small hook 12 carried by the upper Contact fits, preferably a yielding spring nger 13 being clamped to the member 11 and yieldingly engaging the nger 12to prevent radio interference.

The lower end'of the fuse cartridge is received between spring fingers 14 carried by the door, and the lower contact 6 is provided with a shouldered portion l5 which rests upon a metal support 16 secured to the door. A small leaf spring or resilient Contact member 17 is carried by the support in order to insure contact and prevent radio interference, although this feature forms no portion of the present invention.

It is to be distinctly understood that any other suitable means could be employed for removably securing the fuse cartridge to the door, as the specific details of this securing means forms no portion of this invention.

The body portion is provided with a lower terminal member 13 equipped with spaced spring fingers 19 which receive the lower contact 6 when the door is closed. The body portion is also provided with an upper terminal member 20 similarly equipped with spaced spring fingers 2l which receive the upper contact 5 when the door is closed.

Attention is directed to the barrier 9 shown in Figures 1 and 2. This barrier or shield may be circular, as indicated in Figure 2, and is carried at the bottom end of the fuse cartridge or tube Li. The fuse link 8v is looped downwardly around the bottom end of the fuse cartridge 4 and around the barrier 9. The body portion 1 is provided with a cutout 22 and the bottom portion of the door is provided with a cutout 23 which, as may be seen from Figure 2, jointly form a. substantially circular aperture within which the barrier 9 is positioned. The barrier 9 substantially lls the lower opening in the housing, as is obvious from Figure 2, and is located closely adjacent the lower end of the housing so as to prevent the reverse ilow of gases upwardly into the housing.

Although the exact theory of operation of the device is not fully known at present, it is believed that the barrier located very closely adjacent and, in the form shown, at the lower end of the fuse cartridge, prevents the gases from starting backwardly adjacent the open end of the cartridge and consequently the gases do not reverse their direction of flow but are completely discharged downwardly from the free end of the cartridge.

The barrier may completely fill and may seal the lower opening of the housing. For example,

as shown in Figure 3, the door 24 is provided with a tapered opening 25 Within which a yielding tapered, cone-shaped barrier 26 carried by the fuse cartridge 4 fits in a substantially gas-tight manner. If desired, the barrier 2 6 or shield may be formed of rubber or other yielding material. In this form of thev invention the opening 25 is formed wholly in the bottom portion of the door and noty in the body portion 2'? of the housing. The fuse link 28 extendsaround the bottom edge of the tube and around the barrier, the barrier freely yicldingand permitting the complete sealing of the lower opening 25.

In the form of the invention shown in Figure 4, the shield or barrier 29 carried by the fuse cartridge 4 is provided with a cylindrical portion 30 and with an upper ange or inner flange 3l. The opening 32 in the bottom of the door 33 is cylindrical and has a fiat upper face against which the flange 3l contacts. In this case also the body portion 34 does not form a vportion of the opening 32, the opening being formed wholly 4in the door, as stated. The fuse link 35 is looped around the lower portion of Ythe fuse tube and around the barrier or shield 29.

Inasmuch as this fuse link is of very freely yielding or deformable material, it is clear that it will conform itself. to the outline of the opening and barrier, as shown` in Figure 4, and thus a substantially tight joint is maintained, thereby preventing the entrance of gases into the housing or box. l

From actual tests with this device, it has been found that there is a great increase in the rupturing capacity without arcing within thev internal contacts within the housing, as the highly conducting gases formed at the time of the expulsion of the fuse link are prevented irom reversing their iiow and entering the housing.

Further, it will be seen that the device in each of its several forms is very simple to construct and does not materially add to the cost of the construction of the cutout type of expulsion fuse, as the insulating barrier or shield at the lower end of the fuse tube is small and easily applied. It may be as freely handled as any'other type of expulsionfuse and may be renewed and replaced .with the same facility as the usual types of expulsion fuses.

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:

l. Anexpulsion type fuse comprising a housing having a body portion and a door hinged thereto adjacent the lower end, said housing having an opening'adjacent its lower end, an expulsion fuse cartridge carried by said door, said housing and said fuse cartridge being provided with cooperating contacts, a barrier carried at the lower end of said cartridge and forming the bottom of said cartridge and substantially sealing the opening within said housing, and a fuse link extending between the contacts of said fuse cartridge and looped around the lower end of said fuse cartridge and said barrier.

2. An explusion type fuse comprising a housing having a body portion and a door hinged thereto,

said door and said body portion having an opening formed jointly therein and adjacent the lower portion of said housing, a fuse cartridge removably carried by said door and having an open lower end located within said opening and spaced a slight distance upwardly from the bottom of said opening, a barrier carried adjacent the lower end of said fuse cartridge, upper and lower contacts carried by said cartridge, a link joining said contacts and extending through said cartridge and looped around the lower end of said cartridge and said barrier,` and spring terminal contacts carried within said housing and adapted to engage the contacts oiisaid cartridge.

3. An expulsion type fuse comprising a housing having a body portion and a door, said door hav. ing an opening formed in the lower portion thereof a fuse cartridge carried by said door and having a lower open end, a yieldingV barrier carried by said fuse cartridge adjacent said lower open end and sealing the opening within said door, said fuse cartridge having contacts, a link located within said cartridge and joining said contacts and looped around the lower end of said cartridge and said barrier, and stationary contacts carried by said body portion for engagement with the contacts of said cartridge.

- 4. An expulsion type fuse comprising a housing having a body portion and a door hinged thereto, said door having a tapered opening adjacent its lower end, a fuse cartridge having a lower open end, a yielding barrier carried by the lower end of said fuse cartridge, said barrier being tapered and sealing within the tapered opening within said door, contacts carried by said fuse cartridge, a link located within said cartridge and looped around the lower end thereof and around said barrier and joining said contacts, and stationary contacts carried by said body portion and adapted to engage the contacts of said cartridge.

5. An expulsion type fuse comprising a housing having a body portion and a door, said door having an openingin its lower end, a fuse cartridge carried by said door and provided with upper and lower contacts, said fuse cartridge having an open lower end, a barrier carried by the lower end of said vcartridge and fitting within the opening within said door, said barrier having a fiange contacting with the inner side of said door adjacent said opening, a fuse link within said cartridge joining said upper and lower contacts and looped around the lower end of said cartridge and said barrier, and stationary contacts carried by said body portion and adapted to engage the contacts of said cartridge.

ALWIN G. STEINMAYER. WILLIAM D. KYLE.