DE1895660U - PROTECTIVE CAP FOR ELECTRICAL COMPONENTS FOR REMOTE INDICATORS, IN PARTICULAR TELEPHONE SYSTEMS. - Google Patents

Description

RA.730 841 * 11/13/63

S IELlENS & HALSKS Munich, November 3rd, 1963

Stock company Wißelobacherplatz

pa 63/2997

Protective cap for electrical components for telecommunication inobesondero remote telephone systems

The "price increase" concerns a protective cap for electrical, You 'operationally heating components for telecommunications in particular Intercom systems.

The hiring "aims at such a design of the protective cap, that the resulting heat build-up on the components is kept as low as possible.

In low-voltage systems, heat-generating components are installed in large numbers in racks. Eb is not there

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to avoid, to provide these components with caps _s cause impeding the dissipation of heat from the components and an increased heating of the devices. This results in the plant to temperatures which lead and the electrical properties such as electrical resistance, to affect mechanical changes _s for example to a fault of insulating material * ".

Ilan has therefore created the caps from material of high thermal conductivity, for example aluminum or aluminum alloy _5, in which a large area is made available for the heat transfer to the outside air due to the even and rapid heat distribution in the cap. But this hatred alone turned out to be in the case of plants with many _? densely populated circuit boards and with heat-sensitive electronic components as insufficient.

It is known to remove the in such racks Amount of heat from installing the circuit boards in the frame at an incline to the horizontal and / or through the use of fans.

According to the regulation, there will be an additional improvement in the Heat dissipation to the outside air in the area of the covered components themselves caused by the fact that the cap in

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per se "known way from material of high thermal conductivity exists and that their surfaces are designed such that, the inwardly directed surface a high heat absorption and the one facing outwards Surface has a high heat dissipation capacity. This ensures that the thermal resistance between the component and protective cap as well as protective cap and surroundings and thus the temperature gradient between them is lower, i.e. that the heat build-up between the component and the outside air is reduced.

In a special embodiment, the inward-facing surface is roughened with a matt black Covering provided, while the outwardly facing surface is preferably kept blank. One such, as is well known A coating on the inside that has particularly good absorption of thermal radiation is suitable, with less Teiaperaturdifferenz take a large amount of heat, which in the highly thermally conductive material of the cap is quickly distributed on this and from its bare surface to the Outside air is removed by convection without significantly influencing neighboring assemblies by Y-shaped radiation. If, for example, due to the risk of corrosion, the outer surface cannot be kept completely blank, this can be done without significant Reduction of the convective heat emission also with a bare, good heat-conducting covering, e.g. with a

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Aluminum paint. Instead of an aluminum paint a thin layer of high emissivity can also occur if there is a risk of interference barter assemblies due to Y / arms is only slight.

According to a development of the furnace, the transition from the heated component to the cap is supported in that the inward-facing surface is greeted by heat baffles.

Ea is known per se, the heat emission from heated bodies to support the environment by increasing the surface area. In a further embodiment - the inflation is made use of this in that the outwardly facing surface forms channels which extend in the direction the heat exchange flow expected when the components to be covered are installed in a frame. In these channels, the air flow created by the heat exchange moves with increased speed, what also supports the heat removal.

To simplify the creation of such a protective cap, the cap wall is expediently provided with formations provided, whose concave sides serve as channels and whose convex sides serve as heat conducting plates.

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To keep the distance between the component as small as possible and to adhere to the cap, the inward-facing surface is supported "in the event of a further development of inflation the cap in the attached state on the components via one or more electrically insulating spacer elements. This makes the heat through a very small too holding air layer and transferred to the cap by direct heat conduction, whereby the heat resistance accordingly and the temperature of the components is lowered. Instead of individual spacer elements, the heat-absorbing The covering itself can be used as a spacer element, provided that it is made of electrically insulating material.

In the following, the hiring is explained in more detail with reference to the exemplary embodiments shown in the drawing.

It means:

1 shows a protective cap in section

2 shows a section of a protective cap in another embodiment,

3 shows a protective cap in a third embodiment in Cut,

Fig. 4 - a section of the protective cap according to Fig. 3 with spacer elements.

Fig.1 shows a protective cap 1 made of aluminum or auu Aluminum alloy. This material is known to have a

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high thermal conductivity. Your outwardly facing surface 2 is as shown, bare or with a in the Pig. Aluminum paint, not shown, or it can be coated with a, the heat dissipation to die.Außenluft favoring lacquer coating with high emissivity or n be provided with an aluminum oxide coating. The inwardly facing surface 3 has a matt black and roughened covering 4 or provided with a radiator paint or with a copper oxide layer. The surface is enlarged by heat conducting plates 5 and the surface 2 by molded-in channels 6. The channels 6 are such arranged on the protective cap 1 that after placing the protective cap 1 on the, not shown, in A frame built-in or on a plate or in a frame are components in the direction the heat exchange flow occurring in the frame due to the operating heat, which is indicated by an arrow is indicated. This gives the surface 3 a high heat absorption capacity and the surface 2 a high heat dissipation capacity, so that when the protective cap 1 is in place, the heat given off by the components has a smaller temperature gradient is transferred to the protective cap 1, is well distributed in the thermally conductive material and from the said, a surface 2 having a high releasability, again with a small temperature gradient, to which the outside air is released.

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The heat dissipation through the surface 2 and the receptacle the heat through the surface 3 is due to the increase in area aittelü of the channels 6 or the Y / sleeve plates 5 improved, so that there is no annoying heat build-up between the protective cap 1 and the components mentioned can come. In addition, since the channels 6 extend in the direction of the heat exchange flow, the Y / heat output additionally supported.

In Figure 2, a protective cap 7 is shown; which, in generally designed as the protective cap 1, has channels 8 on its surface 2, which intersect and therefore the Y / heat exchange flow to be expected in an equipped frame can be adapted in two directions, what for the installation of the components in the frame or for placing the protective caps 7 on the components is a larger one. ! Freedom gives.

In a further embodiment, as in Pig. 3 shown, a cap 9 is shown, in whose wall formations are embossed, the concave sides in the surface Form 2 channels 1o and their convex sides on the surface 3 Wlirmeleitbleche 11, so that in simple white the Protective cap 9 together with the channels 1o and the heat conducting plates 11 can be created.

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For the cross sections of the channels 6, 8 or 1o bsw. the v / ärr: guide plates 5 or 11 can be used depending on the requirements either as shown, square or rounded forcing can be used.

In Pig.4 a section of the cap 9 (Fig.3) is enlarged shown. In addition to the covering 4 on the surface 3, spacers 12 are provided which, when the cap 9 is in place the components 13 touch directly. The spacers 12 can be arranged on the cap 9 or on the component 13. Hit such spacers 12 can be a very small one Maintain the air gap between component 13 and cap 9. The contact resistance is created by the small air gap and the direct heat conduction at the contact points greatly reduced between component 13 and cap 9 for the heat flow.

6 claims for protection
4 figures

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Claims (6)

P.A.73O84M3.11.63 PA 9/420/3088 -9- Schutzanütirüeho 1. Protective cap for elektrioclie ₅ 'operationally heating components for telecommunication-insbeüonaere' telephone systems, characterized in that the cap (1,7 or 9) consists of material of high thermal conductivity in a manner known to αich and that their surfaces (2 and 3) are designed such that the inwardly directed surface (3) has a high heat absorption capacity and the outwardly directed surface (2) has a high heat dissipation capacity. 2. Protective cap according to claim 1, characterized in that the inwardly directed surface (3) with a dull black, roughened coating (4) is distorted and that the outward-facing surface (2 / preferably kept bright. 3. Protective cap according to claim 2, characterized in that; that the inwardly directed surface (3) is enlarged by heat conducting plates (5 or 11). 4. Protective cap according to claim 2 _5, characterized in that the outwardly directed surface (2) forms channels (6, 8 or 1o), which flow in the direction of the heat flow to be expected when installing the components to be covered in a frame extend. -10- PA 9 / 42ο / 3ο88 -1ο- 5. Protective cap according to claims 3 and 4> characterized in that the cap wall verüehen with Auoformungen iüt, whose concave sides are al υ channels (io) and the convex sides of which serve as ο V / sleeve plates (11). 6. Protective cap according to Anopruch 5 _3, characterized in that the inwardly directed surface (3) of the cap (9 ) abcstütat in the agitated Zuotand on the components (13) via one or more electrically insulating spacer elements (12).