DE2021374A1 - Power resistors - Google Patents

Description

Request for application

I »eis ^: tungsw, i, stalls

Priority ; 3Θ * April -1969 :; KS ■■; U. B. äer «Ho, 820.; 5 58- _v

la. July 1969; tI. &. J 847 783

The jßr: f ± n & tfßg - baz-j ^] ^
.sake -Ui) J'-Bietroaieα

Mirksarakeiifc in i-tezng -auf '. & Ie. JUSLel-tuag -'- öiö-r ■ '' äie ^ οιιροηβηΦβη emz & ngten heat unä special

The dÄrßh elekrterönisßiie ^ [

he output resistance in the 3 *, Γ0πιάηΓαη ^ 3η £ äurah generated Märaet isrfc in the region of the S ^ aictrimik e-iti

Pröbleia, which itöoii .datturcli used in recent years isnt, ..that it became necessary to see the eletetronis xatars to build extremely compact, for example for the

■■ '■.' ■

The heat generated by the individual components in the

electronics can be held either by the individual electronics ; Elements like those in the neighborhood 'Eleaienie b ^ a ^ diieheji .. ^ ilfi ^ gicstarjeiL. To the Ifer

• BAD ORIGINAL

MS .2: 675

wrestling with: effect; mt £ -JUe ^ o ^ ons ^ e "the heat generated is .quickly ueI; s; o completely." ie to be derived ": In the last time Ittsümn ■ JiLe ·: additional components .. Frequently: Joe iörüß" Sear. ■ niaQlKBn 'EJ & men &B' ffixea £ Eot ££ a®. + - «as-« ine solution

lußerdem must ä wsgen: e r KoaisrbEuktioK: ü & r jEilsffl®n ± fi ,, as in a Iie-i-Brt-TMG _{^{BSfid.ars5baiid:}} fe © ii Üem .iaer _ilraiit: .u "-j cylindrical i ! £ .gewickelt s * is the 'xtes to daeir ijpüt-z "element heat generated during' .uiibau ÄesaeiLfeen: sM <e ± n £ Laches chassis d; le ürön'demselben; REII ^:. dre: pass r like Me i * ahe ' ^v idieiJ Boden ä-ea Eleiaenites te tfärme. From ö, ieys: em Srunäe, the ^ imp: e; ratuaEgr.ad shy of each part of the eoid ^: äer Ejoaponente .iunfl asm JShassis different from the 5fem ^ eratur ^ adaaent © n zsiiscfeen ä. & M ■ Ötorteil of the component • ..ano- '. tein- "Jöiiassitsι, foiglieh ^ iano the heat not so iroJD ^wirksani: .Oberteil .the' Koeponsnit ©; aiige.Oieitet,"as'lie risk of hot spots: iim ^r Beireish the Sfeerteiles the .Komponente with it teingt Mar. w © - * iiitiirÄ ■ - the possibility of failure of the .component -distorted ;. "" ■ "■ '■ -'^{; i}

J3S wuirde ¹ now recognized _':> Idass ^ OaektiEonisotoe- El, e; mBnte like \ etwk Ijeistiangsvd.die'rBtänaie \ beträßhtlli.ah -ikieinieir ^ mowed are iömiien because of daduireh & r, 2iel: t © n much ^ MSS & rmi laiirkBafflfeeit de ^ ilbieitimg äer _ generated -heat by; production -a as flat vdLe possible carrion-proof stream, wear.d: a cup component, which is fixed on a flat surface with iron; on the other flat surface opposite to each fastening surface, is firmly attached. so that for the purpose of the second flat surface coming into thermal contact with a problem, each part of the current-carrying component is essentially the same distance from the chassis as the other cables of the current-carrying component. You can even see between all the components that carry the load and the chassis - the same!

BAD ORIQfNAL

BEO; ^ - 3 - 202137A

gradient, creating the highest efficiency of heat dissipation, ν η of the electronic component is achieved. ■

because of the new construction and packing according to the invention The structural components and especially the power resistors have a low profile and a smaller outer surface and are lighter in weight, and their manufacturing cost is lower than with known components of comparable performance ranges. .

For example, a new electronic component such as a power resistor according to the invention is a film of resistive material with a preselected electrical resistance per unit area. The film has a chosen pattern for education a desired number of series or parallel connected Squares. Means supporting the film have a support surface for fastening the power resistor in thermal contact with the chassis and with the support means, whereby a thermal conduction of substantially the same Length between all parts of the film of the resistor material and the support surface of the carrier means. The means of support of the power transistor can be a unitary body made of thermally conductive and electrically insulating material, such as beryllium oxide. However, the carrier means can also be made of a plurality of layers of thermally conductive material, at least one of which is in thermal contact with the resistance film is. This layer "consists of one both thermally conductive and electrically insulating material, such as aluminum oxide or beryllium oxide. The elements are held together by various means. A such a very effective means consists of molded thermoset plastic which, together with fasteners, the parts of the question r means of the resistance are j acts.

Sine other effective possible structure, which is used for the layer-by-layer structure of components ζμτ localization of the generated

009846/1 3CK

BATH ORIGINAL

Offers heat, includes second support means, which is on the side of the resistor film opposite to the first support means are arranged. The two carrier means are advantageously made up of laminar layers and form a solid one Base plate made of thermally conductive material and a plate made of thermally conductive and electrically insulating material in Make contact with the resistive film that is on one of the plates is applied by vapor deposition »This construction made of tarpaulin components, such as the first detailed construction above, can be stacked with rectangular thermally conductive plates between each component or each other components for the production of cooling fins or cooling plates. The components arranged one above the other are then cooled by convection currents, and if higher performance options are required, the components are through Pressurized air passing through the baffles or components is cooled.

A very highly effective and extremely compact power resistor has a round, thermally conductive disc with a bolt protruding from the flat surface, a seal from thermally conductive and electrically insulating material around the bolt and in thermal contact with the flat surface on the side on which the disc has the bolt, a film Made of resistance material with a predetermined resistance value per unit area, which is applied to the surface in a special pattern the seal is vapor deposited away from the disc, means such as a friction ring placed on the bolt and presses against the sealing ring, either in the area of the Surface by being no resistive film or by insulating Material, such as Teflon, to hold the sealing ring against the disc and in thermal contact with it, contact clips, like a metallized film on the sealing ring and in electrical contact with selected areas in the film of resistance material and contact pins in electrical Contact with the contact terminals that see from the

009846/13 (H.

BATH ORIGINAL

HEG 2675 - 5 .-

2P21374

Washer and from the sealing ring for connection to external Lead wires extend outward on.

The process of manufacturing the electrical components consists of creating a thermally conductive and electrically insulating base layer that is more solid or layered Type having a first flat surface and a second flat surface on top of the first surface opposite surface, the printing of electrical connections at preselected points of the first flat surface, the printing of a film of resistance material with a predetermined resistance value per unit area in a 'preselected pattern the iron tarpaulin (surface and with selected parts of the Filmes in contact with the electrical contacts, wherein in terms of the length of the current path through the film between the contacts at the ends of each length of the film the effective width of the length of the film determines the resistance value of the film length and the total resistance value of resistance by the individual lengths of films of resistor material connected in series or in parallel is determined. The method includes additional steps of holding the elements together by using thermoset plastic in a mold to encapsulate the elements Elements on one side of the base plate.

Further features and usefulnesses of the invention result from the figures and the description of an exemplary embodiment. From the figures show:

Fig. 1 is a perspective view of a current-carrying element, such as a power resistor, according to the invention, 'which is shown partially broken isbj.

FIGS. Vi, 2 and 3 are perspective views of parts of the resistor j shown in FIG

009846/1304. ■

BATH ORIGINAL

EEC 2675 - 6 - '"

Pign, 4, 5 and 6 side views of different designs a power resistor according to the invention;

Pig. 7 is a perspective view of the element carrying the resistor film with an embodiment of the contacts of the power resistor according to FIG the invention?

Pig. 8 is an enlarged cross-sectional drawing along section lines 8/8 in Pig. 7;

Pig. 9 is a perspective view of the element carrying the resistor material with contacts for Inclusion of the wire feeds to the power v / idersiaid;

PignJO Ms 14 Top views of the PiIm made of resistance material and the element that supports the PiIm

* _s specific examples of selected coughs

of the resistance material to generate the desired resistance values of the power resistors j

Pig.15 is a side view, partly in cross-section and partially broken off, another type of live element such as one 'Power resistor, adapted to the stratification_, in accordance with the invention;

Pig. 16 a plan view of a layered power resistor des in Pig. 4 type shown;

Pig. 17 is a top view of a layered power resistor des in Pig. 4 with cooling fins in between, the layers of Components with cooling fins can be assembled vertically or horizontally (with the cooling layers th or vertical cooling fins is the version in Fig. 16 and 17 as a side view and as a Prontan ' view shown) and

Pig.18 aQ graph showing the change the performance of lead resistors and the in Pig. 4 is removed, for a © layering with cooling plates in between and with air blown between the layers to varying degrees.

009846 / 13CU

BATH ORIGINAL

The electronic components of the present invention have a layered structure to provide a thermal path of equal length between all parts of the current-carrying element of the component and the chassis on which the component is located is placed on the chassis to effectively dissipate the heat from the current-carrying element. Consequently can use the electronic components according to the invention such as a power resistor, considerably be smaller with / the same performance than the known large components. In addition, the inductance of the power resistors according to the invention is extremely low, which is a means additional benefit. Although this layered construction is not limited to power resistors and can be applied to all current-carrying elements they are described in connection with a power resistor.

A power resistor 1 built in accordance with the invention has a layered construction as shown in FIG Fig. 1 is shown. The power resistor has two basic components, namely the current-carrying element represented in FIG. 1 by the film 2 of resistive material, and

to the

a second to carry the current-carrying element and / delivery a heat dissipation path of equal length between all parts of the current-carrying element and the chassis on which the electronic component is attached.

The support means in Fig. 1 consist of two separate elements, the base plate 3 and a plate 4, the base plate 3 consists of thermally conductive material and can for example Be made of metal or metal alloys. The base plate 3 has two flat surfaces 5 and 6. The lower surface 6 is used to produce a good theraisciien Contact with the chassis to which the resistor 1 is placed, while the surface 5 to produce a good thermal'Kontaktes ait the the resistance film-2. supporting element 4- serves.

Ö098A6 / 13 (H.

BATH ORIGINAL

2Q21374

REO 2675 - 8 -

The surface 6 is by a bolt or screw, not shown here, which extends through the hole 7 through the Extend bolts 10, held in contact with the chassis.

The element 4 consists of thermally conductive material, see above that the heat is supplied from the current-carrying resistor film 2 via the elements 4 and 3 to the chassis on which the resistor 1 is attached. The material of the element 4 acts as an electrical insulator to isolate the current-carrying Film 2 against the metal layer 3 and the chassis on which the resistor 1 is attached.

The resistor also has a means of holding the elements together to create good thermal contact, shown in FIG. 1 as molded thermoset plastic 8. The plastic material 8 is in contact with the resistive film 2 and the elements 4 and 3 by part 9 of enlarged diameter of the bolt 10 extending from the upper flat surface 5 of the base plate 3 extends from. The plastic material 8 is subjected to a rotary motion a Handel 15 along the periphery of part 9 with the increased diameter of the bolt 10 prevented.

Metallizing films 11 and 12 (Fig. 2) are on the element 4 in contact with, the resistive film 2 applied so that a contact for connection with the external supply lines is made. The metal films 11 and 12 are marked with "electrical Contact pins 13 and 14 to enable connection to external feed lines to the power resistor tied together. The metal films 11 and 12 may be made of a gold alloy, for example, and the contact pins 13 and 14 can be soldered directly for mechanical fastening.

The entire device has a low profile and is smaller impressive to its overall size and lighter in weight than known power resistors-comparable performances.

009846/13 (H.

■ ORIGINAL BATHROOM

EEC 2675 - 9 - .- / ν '

For example, a power resistor is according to the invention with an output of 30 watts, it is only about half the size of a Power resistance of conventional type with an output of

25 watts. ·

Because of the layered construction of the resistors according to the invention, they are also essentially without inductance, what represents a further advance over the known designs.

The method for producing such a power resistor or other current-carrying components comprises the steps of creating a thermally conductive and electrically insulating body, such as elements 3 and 4 in FIG be made about beryllium oxide, which has both the properties of good thermal conductivity and good electrical insulation. The next step is to create the contacts on the surface of the electrically insulating body. This can be done by printing with silk screens or by using ceramic printing matrices with the metal in them. The Meta.ll should have good electrical conductivity and can be made of gold or a gold platinum alloy, for example. The ceramic matrix applies the metal to the surface of the base plate, which can be a surface made of ceramic, for example, such as the plate in FIG. 1. The substrate or base plate is then heated in order to cement the metal onto the substrate, Thereafter, a resistive film is applied to the substrate by sifting or vacuum deposition, for example in a selected pattern, the selected areas of which are in contact with the metal film and which serve as a connection to the film. The contact pins, swie about 13 and T4 in Figs. 1 and 2, are attached to the metal connections. Dip pins can be connected directly to the film by soldering the film on it, or the pins can be inserted

;. 0-09848 / 13 (U

• · ■■■■■■■ BAD ORIGINAL

REC 2675 - 10 -

rather and more advantageous through the use of connection eyelets connected to the film as shown in Figures 7 and 8 is. When using a substrate, this is applied to the base plate and then the combination into a Form used for encapsulation.

Further designs of such film power resistors are shown in FIGS. 4, 5 and 6. The one shown in FIG Execution differs from that in Pig. 1 tidal resistance in that the thermally hardened. Plastic with is anchored in the elements of resistance. The resistor 20 in FIG. 4 has a base plate 21 with a bolt 22 on, which extends from the upper flat surface 23 on which rests a plate 24 as a support for the film of resistance material 25. The top surface 23 of the Base plate 21 is a bit smaller than the outer circumference 26 of the base plate 21 and is turned underneath to a lip 2? to build. The peripheral edge of the flat surface 23 with smaller diameter has ribs 28 for cutting in the plastic part 29 * so that the plastic part is not against twist the other parts of the resistance element In addition, the plastic part is held in its position by the lip 27 below the surface 23. As above has been carried out, the intermediate element, such as the plate 24 of the resistor 20 in Fig. 4 under the element 4 of the Resistor 1 in Fig. 1 can be omitted and the resistor film be printed directly on the base plate 21, if this is made of a material that both is good thermally conductive as well as electrical insulating- such a material is beryllium oxide. This particular execution is not shown in the drawings.

Resistor 30 shown in Fig. 5 has a similar one Construction on like resistors 1 and 20, however other means of holding the thermoset plastic mold 31 in position. Has 30 in resistor the base plate 32. a vertical continuation 33 and

009846/1304

BATH ORIGINAL

REO 2675 - 11 -

a horizontal protrusion 34 that holds the plastic in the holds correct position. The inner edge of the horizontal protrusion 34 may be fluted to accommodate the plastic to prevent the other elements of the resistor 30 from rotating.

Another embodiment of a power resistor according to the invention is in Pig. 6 shown. The resistor in Fig. 6 has no plastic depilleniente to hold it together in thermal contact and to protect the elements against 2rer ~ disturbance in which the resistance is embedded, but uses other means of holding the individual elements together,

The resistor 40 has a base element 41 with a bolt 42 extending from the top surface of the base member

extends. Around this bolt 42 and in thermal conmit
On the upper surface of the base plate 41, an electrically insulating and a thermally conductive plate 47 is provided, on which a resistive film 46 is applied. The bolt 42 has a portion 43 with a larger diameter which cooperates with the miVc ring 44 to hold the elements together. Since these C-rings are mostly made of metal bond, an electrical insulator, for example a Teflon ring 45 ', is arranged between the film 46 made of resistance material and the ring 44'.

The ring 44 presses against the enlarged part 43 of the bolt 42 to hold the elements together. Anyone can do the ring have a suitable shape with, for example, a round cross-section. As shown in Fig. 6, the ring 44 has a wedge-shaped Cross-section, with the inner edge on the inner Circumference of the upper surface of the plate 47 if ' the film 46 of resistive material does not cover it Part of the surface extends. Otherwise it can be an isolating one Ring, such as a Teflon ring 45 between the ring 44 and the Plate 47 to be placed.,

009846/1304

BATH ORIGINAL

REG 2675 - 12 -

Thereafter, a film of electrically insulating material can be applied over the outer surface of the base plate 41, the resistive film 46 and the plate 47 for electrical insulation of the resistor sum protection of the elements against destruction be sprayed.

For fastening the contact pins at a point in which If they make electrical contact with the metal film at which the resistive film ends, the use of a mechani is to be seen Connection expedient, the good electrical contact between the metal film and the contact terminals si- " created. Such a mechanical connection is shown in FIGS. 7 and 8, in which the plate 50 has one on it printed film 51 of resistive material. A metal film is also used to delimit the resistance film 51 52 and a metal film 53 are printed on the plate 50 at the ends of the resistor film 51. In electric Contact pins are in contact with the metal film ends 52 and 53 54 and 55.

The mechanical connection of the contact pins can be better described with reference to FIG. 8, in which an enlarged Part of the cross-section along lines 8/8 in FIG. 7 is shown. The contact pin 54 has a hole 56 that over a hole 57 in the plate 50 lies. The hole 57 has an enlarged "portion 58 for receiving the lower end a connection eyelet 59. The connection eyelet 59 acts with the Hole 57 in plate 50 and hole 56 in connector pin 54 together to attach the connector pin to the metal film 52 in the correct position. Thereafter, the upper end 60 of the connection eyelet 59 is rolled up or up crimped to hold the contact pin 54 against the metal film 52 while making good electrical contact to establish the "mechanical fastening of the contact pin in its position. When using this" method of attachment the contact pins and if the elements of the resistor are encapsulated with the aid of thermally hardened plastic,

009845/1304

BATH ORIGINAL

REC 2675 - - 13. τ- · ■ '■■■■:. ■■■■

like it in Pig. 1, the plastic flows through it hole in the metal fastening eyelet and fill the enlarged Hole 58, the tint granting the connection eyelet 59 against all Elements is isolated on which the plate 50 is located. . .- -,

From Pig. 7 it can be seen that the connecting pins 54 and 55 paragraphs 120 and 121 that are close to the edge of the Plate 50 are located. These paragraphs are within the outer periphery of the mold or encapsulating material and anchor the pins within of the material, this way the pins will be in the Form material anchored.

The contact pins 54 and 55 have additional openings 122 and 125 near the holes through which the connecting eyes go through. The holes 122 and 123 make the contact pins somewhat flexible and reduce the bending stress the connection lugs 59 in Fig. 8, so that the mechanical and electrical connection between, the contact pin and the metallic output is not destroyed.

In some applications it is desirable in place of contact pins wire feeds for connection between the power resistor and outer wires. One

with such construction is in Fig. 9 in connection / a plate

70 used in a power resistor can. On the plate 70 sinxl. a film of resistance material

71 and limitations in metal film kojitakten 72 and 73 to ge *

prints. ;

Corresponding small metallic coils or connection lugs 74 and 75 are attached in electrical contact with the films 72 and 73. These coils 74 ¹¹²¹ O 75 can be held in the correct positions in a manner similar to the connection eyelets 54 and 55 in FIG. For this purpose, a metallic connection eyelet is passed through the coil 74 and crimped at its upper end so that it is in contact with the coil 74 and

0Ö98467130A

REO 2675 -H-

holds it in place. Then a guide wire can be used 77 wound around the coil 74 and soldered or otherwise connected * to the coil. Of the Feed wire 77 can also be connected directly to the metallic Film contacts 72 and 73 are connected. It is desirable that when using lead wires a certain Length of such wire is located inside the encapsulation so that the wire does not come off the connection easily can be pulled off. Let it be useful that a piece of wire with a wire corresponding to 5 times the diameter of the wire Length or even longer in the whole or / the plastic should be embedded. -

Another advantage of the invention lies in the fact that it is easier to adjust the resistance value of the power resistor Over a large area solely through the control of the thermally conductive and electrically insulating carrier material to be applied film and the appropriate arrangement of the metal-film contacts in relation to the resistive film. the Use of new resistance patterns additionally increases the range of resistance values and the versatility of the Power resistance. The raie cough does more of a radial one Current conduction as one lying in the direction of the circumference Conduction around the ceramic or electrically insulating substance on which the film is applied.

The resistive film may be that shown in Fig. 2, for example Have Grundiauster. The length extends from the metal film 11 to the metal film 12 and results in a circular one Line path. This length can be changed by changing the position of the metal film contacts and by increasing or decreasing the Length of the resistive film to make contact with be changed or adapted to the metal film.

For example, in the embodiment shown in FIG have a length that corresponds to 10 times the effective width of the film * so that the pattern 10 in a row

0-09846 / 1304-

BATH ORIGINAL

REG 2675 - 15 -

tete squares of the resistor film. Has the resistance sfiIm. a resistance of 100 ohms per square, then a resistance of 1,000 ohms has thus been created. Has the film 10 ohms per square * then. is the resistance / ert 1Ou ohms, and at a resistance value of 100,000 ohms per The square of the resistance is one mega-ohm. So it can be a wide variation of the resistance value with this basic pattern solely by using different resistance materials can be achieved. ■.

An even wider range of resistance values can go through Using various film patterns of resistive material, including new radial routing patterns, can be created. Some other patterns are shown in Figures 10-14. In Pig. 10, the PiIm 80 made of resistor material has a length which is 150 times the width of the pattern so that the pattern is 150 squares of resistor material connected in series generated. So if the resistance value per square material is 100 ohms, then there is a resistance of 15,000 ohms won. The resistor film 82 shown in Pig * 11 has a serpentine-shaped pattern, the length of which is equal to 170 times the width is, making 170 squares of such resistor material are generated.

A resistance value which is smaller than the square of the egg-NEM Widerstanösmateriales of the film corresponding value, is generated by a _v in Figure 12 .gezeigtes new Radialleitwegmuster. In FIG. 12, the metal film 84 is printed around the inner periphery of the plate 85, while the metal film 86 is printed along the outer periphery of the plate 85. Between the two metal films. 84 and 86 a film of resistive material 87 is printed so that the length of the current path between the metal film contacts is approximately one-tenth the width of the resistive filiaes. With such a pattern with a tenth of a square and a resistance of 100 ohms per square of the resistor material, a resistance value of

009846/1304 -

BATH ORIGINAL

EEC 2675 - 16 -

Get 10 ohms. The patterns shown in FIGS. 2, 10, 11 and 12 show no separations between the films Resistance material on. In Figs. 13 and 14/3 the patterns are shown in which the resistor films are divided to produce a desired resistance value.

The pattern shown in Fig. 13 has 3 segments of in series switched on radially conductive films. The plate 89 has a metal film contact 90 for approximately near the outer periphery a quarter of the length of the circumference. A metal film contact 91 extends near the inner periphery of the plate 89 about a quarter of the circumference. Metal films 92 and 93 extend accordingly near the inner and outer circumference over about a quarter of the corresponding circumference. Between the metal film 90 and part of the metal film 92 is a segment of resistive film 94 with a Radial route. Between the metal film 91 and part of the Metal film 93, a segment of resistive film 95 is provided. A third segment of resistive film 96 is between the metal films 92 and 93 are provided. Each segment has a length that is effectively one »third of the width, so that each segment is a third of the square. The three segments are connected in series and give a total of a square with a large area for heat dissipation.

Another effective pattern is shown in FIG. The plate 105 shown in Fig. H has a metal film contact 106 diametrically opposite a metal film contact 107. There is a film between the two film contacts 106 and 107 of resistive material 108 on the left side of plate 105 and a film of resistive material 109 on the right Side of the plate 105 provided. This pattern creates two segments of resistive film, each one of 5 times Have width corresponding to length, so that there are 5 squares in each case. When using resistor material with 100.0hm so each segment has a resistance of.

0098Λ6 / 130Λ

ORIGINAL INSPECTED

500 ohms. Segments 108 and 109 are connected in parallel between metal film contacts 106 and 107 so that the resistance for this particular pattern is 250 ohms.

Another layer pattern for conductive components like Line resistances are shown in FIG. The in fig. 15th The construction shown is advantageously used when the resistors are layered for some reason should, if about the generated heat in the envelope of the Resistances should be localized. Am another advantage of the Stratification of resistors is that the amounts of power can be easily reached and even increased by blowing air or other coolant over the surfaces of the layered 'resistors.

The resistor shown in Jig.15 is a first base plate

130 in the same construction as the base plate 21 * in Pig. 4 on. However, this special construction is not necessary as long as only a thermal dissipation for the resistance film is provided.

The resistor shown in Fig. 15 also has an electrical insulating plate 31 over the base plate 150. The plate

131 carries a resistive film 132 and contact means (not shown). On the side of the resistance film 132 opposite the base plate 130, a second base plate 133 is arranged, which is separated from the resistance film 132 by an electrically insulating plate 134.

The plate 130 has in the center a bolt 135 on which the plate 133 is advantageously properly secured to hold the elements together. Alternatively, the elements can be held in place by molded thermally hardened plastic that engages under-turned edges in panels 130 and 133, as is also the case with the resistor shown in FIG. On each pail the conductive element, such as the resistive film 192, is sandwiched between two base plates

009845/1304

* OBlGlNAL INSPECTED

smooth surfaces for attachment to additional resistors. . 'Cooling fins or chassis layered. With this structure, the Heat «» me for more effective dissipation and cooling of the Resistance can be derived in two directions.

The current-carrying components, such as power resistors, can advantageously be in the in the Pig. 16 and 17 shown Kind of layered, these resistors have a layer structure. For purposes of illustration it is assumed that the ski resistances of FIGS. 16 and 17 are those shown in FIG Have structure.

In Fig. 17, eight planar power resistors 140 are represented by right-angled, thermally conductive plates 141 separated. The end plates, like the plate 142jkßnn /, are also included in the layering be. The layers are held together by bolts 143 and cooperating nuts 144 and 145, the Bolts 143 through holes in resistors 140 and the plates ! £ 1 leads through. The layers can be with plates or Ribs / vertical or horizontal position as well as in other positions. With an arrangement of the plate ^ or ribs in the vertical direction, more heat is dissipated by convection currents than when they are arranged in the horizontal direction Plates.

FIG. 18 shows a graphical representation of the various possible power values for individual power resistors of the types shown in FIG. 4 and in FIG. 17 layered with aluminum plates of 5 »08 cm 5.08 cm χ 0.10 cm between the resistors shown, which are attached at one end and not otherwise. . The curve 150 in Figure 18 illustrates the performance of ¹ against the flow of air through the individual resistors and the lamination plates constitute the power measured sizes of the various resistors with cooling duroh convection in horizontally arranged plates LSI. marked by point 151 of curve 150. Increasing performance when the plates are arranged in different

009846/1304

INSPECTED

REG 2675 - 19 -

tical direction is illustrated by the point 152 of the curve 150.

Air with a temperature of 25 ⁰ O. and a pressure of 1 atmosphere was blown to the resistances of the lamination to the curve 150 in Fig. To earn 18. The air flow was measured in KuTaik feet per minute (cubic centimeters per minute). If the cooling is sufficient, the output rate of the resistors increases over the cabin with simple convection cooling.

The convection of the stratification and the air blown in with pressure for cooling not only increases the power rate of the resistors but also creates an effective way of localizing and dissipating the heat generated by the power resistors. This property of the layer construction with efficient heat pipe can advantageously · Presiding at Sion equipment, such as computers and Labortestein devices are used. ₅

■ 009846 M 304

ORIGINAL INSPECTED

Claims (1)

Claims ViV power resistor, consisting of a base plate (3) made of thermally conductive material, with a first flat surface (5) and a second flat surface (6) on the side of the base plate (3) opposite the first flat surface (5), means (9 _S 10) for holding molded thermally hardened plastic (8) over the first flat surface (5) of the base plate (3), a thin plate (4) made of thermally conductive and electrically insulating material resting against the first flat surface (5), "a PiIm (2) of resistor material with a preselected resistance value per unit area for a given thickness in a selected pattern on the surface of the plate, which stands out from the first flat surface (5), of molded, thermally hardened plastic (8). for containment of the resistance material (2) and the plate (3) and as an electrical insulator and protection against damage, and from contacts (11, 12) for connection leads (13, 14) to the resistor, which are in electrical contact with certain areas of the film (2) and extend through the plastic material (8). 2. Power resistor according to claim 1, characterized in that means (7) for fastening the base plate (3) on a chassis with the second flat surface (6) in thermal contact with the same, electrical components with a flat surface in thermal contact with the first flat surface (5), leads between the electrical components and those for connection with the external circuit outside the part, and means for enclosing the electrical components are provided on the first flat surface and leaving the second flat surface exposed. 00 9 8 Λ 6/1 304 EEC 2675 - «.- 3. Power resistor according to claim 1, since d u r c h .. g-'e k e η η ζ e lehn et that differ from the second flat surface (23) a bolt (22) 42) extends upwards that a first plate (47) of thermally conductive and electrically insulating material around the bolt (22, 42) arranged and in thermal contact with the second ' flat surface (23) is that a film (46) of resistive material with selected resistance per unit area is applied in a preselected pattern to the surface of the plate (47) rising from the first flat surface of the base plate, that means (44, 45) for holding the plate (47) against the base plate (41) and in thermal contact therewith and Means for forming an electrical Contact with predetermined areas of the film (46) Äes Wideystandsmattrials are provided for connection to external leads. 4. Solving resistor according to claim 3, characterized g e k ο η η ζ ei c h η e t that the holding means (44, 45) a knurled edge along the perimeter of the times have flat surface and the knurled edge is set back against the outermost circumference of the base plate and under the knurled edge a protruding lip forms that means are provided for encapsulating the plate and the resistor surface which is in the knurled edge and engage the formed lip and hold it in place will. 5 power resistor according to one of the preceding claims, da d u r c h g e k e η η ze i c h η et that. an insulating layer on the exposed parts of the second flat surface and the plate (47) and the resistive film (46) is applied. '6. Power resistor according to one of claims 3 to 5, d ä «durch ch geke η η ζ calibrated η et that the '■ .- ■' ■ '■. ■. "■ ■ f 009 846/1 30 4 , ORIGINAL INSPECTED Ji protruding bolts (15, 22, 42) one passing through the bolt from above to the first flat surface of the base plate Has a hollow opening (7) for fastening the resistor to a chassis. 7. Power resistor according to claim 3, characterized characterized in that the contact means include flat contact tongues (13, 14; 54 »55) and that these are located above the base plate (3) in a plane extending parallel to the second surface (6). 8. Power resistor according to claim 7, characterized in that the contact tongues (% , 55) have holes (122, 123) in the part lying within the area of the base plate to relieve spring stress on the contact tongues (54, 55). 9. Power resistor according to claim 7 or 8, characterized in that the contact tongues (54, 55) paragraphs (120, 121), which together with the holding means hold the contact tongues in place. 10. Power resistor according to claim 3, characterized characterized in that the contact means are metallic Film ends (52, 53) on the plate (50) extending from the areas of the film (51) of resistive material to the flat contact tongues (54, 55) extend, and that the contact tongues (54, 55) are in electrical contact with the metal film ends (52 * 53) and for making contact with external feeders extending outward. 11. Power resistor according to claim 10, characterized in that in each area in which the contact tongues (54, 55) with the metal film ends (52, 53) are in electrical contact, one from the bottom of the plate 009846/1304 reg 2675 ^ ": ->-; ^ ^/ ^^ - '■" 2021374 (50) from a countersunk hole through the plate it is provided that the contact tongues (54 »55) with the holes holes matched in the plate (50), means for retaining the contact tongues (54 »* 55) are provided in electrical contact with the metal film ends (54» 53), and that the holding means through the holes in the plate (50) and in the contact tongues ('54 »55) have metal eyelets leading through, · the ends of which are at the top of the contact tongues (54, 55) and in the countersunk holes of the Plate (50) can be folded over * 12. Power resistor according to one of the preceding claims, d a d u r c h e k e η η ζ e i c h η e t, .daß the Y / resistance filra made of material with a preselected resistance per unit area is applied in a selected pattern on the first flat surface and certain parts of the resistive film are in contact with the contact means, the length of the wide band film in the direction of current flow between the contact ends on each side of each film related to the effective width and length of the film Resistance in the direction of flow of the film is determined and the total resistance by those connected in series or in parallel individual film lengths determined on the first flat surface is. 13. Power resistor according to one of the preceding claims, characterized in that the contact means flexible insulated wire feeds with a length which corresponds to at least five times the diameter of the wire, include «. ö · ■. "■ '■ <o 14 «power resistor according to one of the preceding claims. ' 4>. marriage, characterized in that ^ the resistance filters and / or letallf ilmenden one or more beg- " "- * elements made of resistance film with radial StroiTirich- «*> ο, have grooves on the plate. * - '■ "■■■. ■■," ■'. - ■ .- ■■■, 15. Power resistance, thereby. gek e η η - ". show that there is a first base plate (130) with a first surface, a second surface parallel to this with a heat conduction path from the first surface to the second, an electrically insulating part extending from the second surface (131), a resistive film (132) applied to the first surface, a second Plate (133) with a first surface and a second surface parallel thereto with a thermal conduction path from the first surface to the second surface and an electrically insulating part (134) are provided, and that the part (134) extends from the first surface and h is in contact with the resistive film (132) and with the first surface. 16. Sheet resistor, consisting of several power resistors according to one of claims 1 to 15, characterized characterized in that a plurality of power resistors (140) separated by thermally conductive plates (141) are arranged in layers one above the other, that the plates (141) have a substantially larger cross-section than the power resistors (i40) / and that means (143, 144) for holding together the power resistors (140) and those arranged between them thermally conductive plates (141) are provided in a layered arrangement. 0098 * 6/1304 BATH §If§