DE7723699U1 - Thermal fuse - Google Patents

Description

In the interests of operational safety, high demands must be placed on thermal fuses: The fuse must be able to be continuously or intermittently loaded with the operating current at all temperatures below the upper limit temperature without responding. But will in the T? _e hlerfall such exceeded by a shorted turn, the upper Grenztemperatuz without the current increases significantly, the fuse must turn off quickly in order to prevent further increase of the now thermally labile _ temperature and thus exclude claims

§ essen.

ä In the following, the constructive

Measures are specified that are necessary to meet this requirement

are agile.

'' Fig. 1 shows the basic structure of a thermal

securing in longitudinal section

Fig. 2a shows the longitudinal section and 2b shows the cross section in the edge zones of a thermal fuse U-shaped folded sr carrier film 1

Fig. 3 shows a cross-section in the R _a ndzonen _ a metallized and provided with an adhesive film carrier sheet 1 in the intermediate stage to Faltwickel

Fig. 4a a longitudinal section and 4b a cross section in the edge zones of the folded fuse

Fig. 4c and 4d longitudinal sections through a V / indung of the folded roll, with the frontal contact in case 4c by sprayed-on metal, in the case of 4d takes place by inserted metal foil.

Fig. 5 is a longitudinal section through a moisture-proof built-in thermal fuse.

Inn Fig.-Isind on the temperature-resistant plastic film Λ In the edge zones high-melting metals 2 and over J " fanze ^ width of the tearing metal covering 5 vaporized. The connections 5 and 6 are soldered or welded in the usual way tinned connecting strips, wires ^ er tinned copper braid. To protect the tearing metal covering against corrosion, the plastic film ^ is attached

fs; eat; £ ^ _o k: ta ^^^

! -For installation in bowls oi er ^ W ^; ^ »; ¹ "

7723699 25.0179

Fig. 2 shows the structure of a fuse with the same area, slightly greater thickness, but for twice the height
Operating current compared to the fuse Fig. 1 can be used. ι The metalliesierte carrier film 1 is U-shaped is bent so that the [current-carrying metal contact pad 3 in each case doubly f the outstanding on the side connecting strip 5 and 6. FIG.
The resulting in the longitudinal direction of the fuse between the connecting strips is expediently by a
double-wide adhesive film also folded over in a U-shape 4
filled out. |

For even larger flows, a foldable winding structure is suitable, \

as shown in Figs. 3 and 4. A cut of the |

Carrier film 1 in the edge zones with vapor-deposited higher melting J

zenden material 2 and the tearing metal coating 3, as well as I.

of the adhesive film 4- in the first, coated on both sides

Fig. 3 \ Fig. 4 a shows a longitudinal section of the folded roll, 4 b shows a cross-section

the point F. How the contact on the front sides by -

e.g. material applied with a metal spray gun g

or by inserting a metal foil in the edge zones

can be shown in Fig. 4c and 4d. |

The installation of a fuse, for example with tinned copper ^{wire 5 and 6 ¥,} in the fuse surrounding the fuse

Isolation film δ is shown in Fig. 5 · The end faces 9 and 10 I

are sealed by a moisture-proof compound. |

If the fuse in the device concerned against moisture |

and chemically active gases are protected, this input |

construction not required. |

For choke coils in fluorescent lamp systems, an up | Tear temperature of the current-carrying covering of about 230 ° C
required to prevent erands. Is suitable for this
especially tin. The connections are made according to the status
the TecbniK. manufactured. A good contact strength is
for example guaranteed by vapor deposition of copper in the peripheral areas. For the carrier film 1 and also the insulating film
7, for example, a polyimide film is suitable, the thickness of which is of the order of 20 µm (* 0.020 mm).

7723699 01/25/79

Claims (7)

Utility model to the fertilizer temperature fuse protection claims 1. Thermal fuse, especially for choke coils, with an electrically conductive material, the melting point of which is the one to be monitored Temperature is adapted and that on an insulating material underlay that is in extensive contact in the device to be protected is vaporized and that regardless of the current strength that is set in the event of damage above a predetermined limit temperature melts with island formation and interrupts the circuit, characterized in that for contacting in the strip zones as a base for the tearing metal covering (3) at least one high-melting point Metal (2) is vapor-deposited to which the connections (5 and 6) are pinned or welded to ground, and that the tearing Metal covering (3) protected against corrosion by an insulating film (7) it: t. 2. Thermal fuse according to claim Λ, characterized in that the carrier film (* 1) is bent in a U-shape and the connecting strips (5 and 6) protruding on the side contact the current-carrying metal covering (3) twice. 3. Thermal fuse according to claim 1, characterized in that that the carrier film (Ϊ) is folded, the contact duxc: inserted connection strips or through on the front sides sprayed on solderable or weldable material (Fig. 4-c) or by means of inserted metal foils (Fig. 4 d). 4-, temperature fuse according to claim 1, characterized in that that as a carrier film (1) and as a counter film (7) according to the permanent heat resistance required in operation for around 150 ° C polyethylene terephthalate film (e.g. HOSTAPHAM), polyimide film (e.g. KAPTON) is used for significantly higher temperatures. 5. Thermal fuse according to claim 1 characterized in that that an adhesive film is applied to the metal covering (3), which in the low temperature range is a polyethylene film ,, at higher temperatures a chemically neutral adhesive with a temperature below the tear temperature of the electrically conductive material lying softening point. 6. Thermal fuse according to claim 1, characterized in that that in the "edge zones on the carrier film (1) first copper and above it, tin is vapor-deposited over the entire width as a tearing current-carrying document. 7. Thermal fuse according to claim 6, characterized in that the thickness of the vapor-deposited copper and tin coating in each case is on the order of 0.1 u. 8o temperature fuse according to claim 7, characterized in that individual metal coatings, e.g. the copper coating, are galvanically are reinforced. 7723699 01/25/79