SE511701C2

SE511701C2 - Method and tool for manufacturing antenna unit, especially antenna unit for mobile phones and similar with metallic core tubular in form of wire and jacket composed on injectable insulating material

Info

Publication number: SE511701C2
Application number: SE9800809A
Authority: SE
Inventors: Peter Stambeck
Original assignee: Munkplast Int Ab
Priority date: 1998-03-12
Filing date: 1998-03-12
Publication date: 1999-11-08
Also published as: SE9800809L; SE9800809D0

Abstract

The antenna unit has an insulating jacket that is injection molded in 2 steps, with a metallic core (10) with a jacket part (15) shaped as half a tube cylinder while the remaining parts are supported inside a mold cavity adapted to the core shape. The molding tool and the core are displaced with respect to each other so that the core with the jacket is supported inside a second mold cavity. The still bare part of the core is provided with a second jacket supplementary to the first and shaped as half a tubular cylinder.

Description

511 701 2 steg, under vilket kärnan till större delen av sin längd genom sprutning förses med en första höljesdel i form av en halv å rörcylinder, vilken röreträdesvis har väsentligen likformig väggtjocklek, har sidoväggar liggande i nämnda delningsplan och ändväggar liggande tvärs mot höljets axellinje, medan kär- nans övriga del vilar i en till kärnans form anpassad formhà- lighetsdel och avstöds av denna formhålighetsdel, att kärnan med den på denna påsprutade, första höljesdelen frammatas axiellt en sträcka motsvarande den första höljesdelens längd, samt ett andra steg, under vilket den ännu obelagda delen av kärnan till större delen av denna dels längd, likaledes genom sprutning förses med en andra, till den förstnämnda höljes- delen komplementär höljesdel i form av en halv rörcylinder, vilken röreträdesvis har väsentligen likformig väggtjocklek, har sidoväggar liggande i nämnda delningsplan och ändväggar liggande tvärs mot höljets axellinje, medan kärnan tillsammans med, den på denna påsprutade första höljesdelen vilar i en till denna första dels form anpassad, andra formhàlighetsdel och avstöds av denna formhålighetsdel. 511 701 2 steps, during which the core is for the most part of its length by spraying provided with a first casing part in the form of a half-tube cylinder, which tube has substantially uniform wall thickness, has side walls lying in said dividing plane and end walls lying transversely to the axis line of the housing, while the other part of the core rests in a mold holding part adapted to the shape of the core and is supported by this mold holding part, that the core with the first casing part sprayed on it is axially advanced a distance corresponding to the length of the first casing part, and a second step, during which it still uncoated part of the core for the greater part of the length of this part, likewise by spraying is provided with a second, to the first-mentioned casing part complementary casing part in the form of a half tube cylinder, which tube tree has substantially uniform wall thickness, has side walls lying in said dividing plane and end walls lying transversely to the axis of the housing, while the core together with, the one on d The first casing part sprayed on rests in a second mold cavity part adapted to the shape of this first part and is supported by this mold cavity part.

Enligt uppfinningen är det lämpligt att den andra pàspru- tade höljesdelen, genom motsvarande utformning av den för denna höljesdel avsedda formhålighetsdelen, ges en mindre axiell längd än den först påsprutade höljesdelen.According to the invention it is suitable that the second sprayed casing part, by corresponding design of the mold cavity part intended for this casing part, is given a smaller axial length than the first sprayed casing part.

Enligt uppfinningen är det vidare lämpligt, att man, företrädesvis genom kombinerad radiell och axiell insprutning, så att viss rotation och turbulens hos den insprutade massan uppkommer, under ett tredje insprutningssteg förser antennen- heten med en knopp, liggande i ett formhålrum runt kärnans topp och i intim kontakt med åtminstone den första påsprutade höljesdelen.According to the invention, it is furthermore suitable that, preferably by combined radial and axial injection, so that some rotation and turbulence of the injected mass arises, during a third injection step the antenna unit is provided with a knob, lying in a mold cavity around the top of the core and in intimate contact with at least the first sprayed casing member.

Det har ännu icke hunnit utredas närmare, men det vill synas såsom om det är lämpligt enligt uppfinningen, att efter smärre modifikationer av verktyget tillverka s.k. dual-anten- nenheter, dvs. antennenheter innehållande två parallella, sida vid sida och på något avstånd från varandra samt i verktygets nämnda delningsplan liggande antennkärnor, varav den ena lämp- ligen är något kortare än den andra till anpassning efter de i praktiken förekommande frekvensområdena. 3 511 701 Sannolikt är det också möjligt, att efter motsvarande modifikationer av verktyget på liknande sätt tillverka även fs.k. teleskopantenner.It has not yet been investigated in more detail, but it would seem as if it is appropriate according to the invention, after minor modifications of the tool to manufacture so-called dual antenna units, ie. antenna units containing two parallel, side by side and at some distance from each other and in the tool's said division plane lying antenna cores, one of which is suitably slightly shorter than the other for adaptation to the frequency ranges occurring in practice. 3 511 701 It is probably also possible, after corresponding modifications of the tool, to also manufacture fs.k. telescopic antennas.

Uppfinningen kommer att beskrivas närmare i det följande med hänvisning till bifogade ritningar, på vilka en såsom exempel vald utföringsform av ett verktyg för tillverkning av en antennenhet enligt uppfinningen visas.The invention will be described in more detail in the following with reference to the accompanying drawings, in which an exemplary embodiment of a tool for manufacturing an antenna unit according to the invention is shown.

Figur l visar ett första arbetssteg under antennenhetens tillverkning; Figur 2 visar ett andra arbetssteg under antennenhetens tillverkning; Figur 3 visar ett tredje arbetssteg under antennenhetens tillverkning.Figure 1 shows a first working step during the manufacture of the antenna unit; Figure 2 shows a second working step during the manufacture of the antenna unit; Figure 3 shows a third working step during the manufacture of the antenna unit.

Den rätta förståelsen av uppfinningen och beskrivningen därav underlättas om de angivna ritningsfigurerna placeras vid sidan av varandra, från vänster åt höger på ritningen med antennkärnans delavsnitt liggande i linje med varandra.The correct understanding of the invention and the description thereof is facilitated if the indicated drawing figures are placed next to each other, from left to right in the drawing with the sub-sections of the antenna core lying in line with each other.

Enligt fig. 1 är en kärntråd 10 av lämpligt material, t.ex. en nickel-titan-legering, och med en ytterdiameter av exempelvis 0,9 mm införd ett första, med ll generellt beteck- nat formhålrum mellan två verktygshalvor 12 och 13. Detta för- sta formhålrum 11 är så utformat, att man i detsamma genom in- sprutning av en lämplig plastmassa i en första del 11A i verk- tygsdelen 12 genom kanaler 14 kan förse kärntråden ll med en första höljesdel 15 i form av en halv rörcylinder med väsent- ligen likformig väggtjocklek, sidoytor 16 i plan med verkty- gets delningsplan D och ändväggytor 17A, l7B tvärs mot kärn- trådens 11 axellinje. Härvid vilar kärntråden med sin ena halva i ett spår 11B i den på ritningen undre verktygshalvan 13.According to Fig. 1, a core wire 10 is of suitable material, e.g. a nickel-titanium alloy, and with an outer diameter of, for example, 0.9 mm inserted a first, with 11 generally denoted mold cavity between two tool halves 12 and 13. This first mold cavity 11 is designed so that in the same by injection of a suitable plastic mass into a first part 11A in the tool part 12 through channels 14 can provide the core wire 11 with a first casing part 15 in the form of a half tube cylinder with a substantially uniform wall thickness, side surfaces 16 in plane with the tool pitch plane D and end wall surfaces 17A, 17B across the axis of the core wire 11. In this case, the core wire rests with its one half in a groove 11B in the lower tool half 13 in the drawing.

Enligt fig. 2 förflyttas kärntråden härefter axiellt en sträc- ka åtminstone motsvarande den första höljesdelens 15 längd, varefter kärntråden genom insprutning av plastmassa förses med en andra höljesdel 18 under det att den första höljesdelen 15 med inneliggande kärntråd får vila i en efter den första hö- ljesdelens 15 ytterform avpassad formhålighet 19 i den på ritningen övre formhalvan 12. Det inses, att höljesdelarna 15 och 18 till sin yttre form kommer att bli i allt väsentligt EH 511 701 4 lika.According to Fig. 2, the core wire is then moved axially a distance at least corresponding to the length of the first casing part 15, after which the core wire is provided by injecting plastic mass with a second casing part 18 while the first casing part 15 with embedded core wire is allowed to rest in one after the first hay. the outer shape of the bearing part 15 adapted to the mold cavity 19 in the upper half of the mold half shown in the drawing. It is understood that the housing parts 15 and 18 will be substantially equal in their outer shape.

I det första sprutningssteget kommer enhetens läge att 'styras genom att kärntrådens ena hälft styrs i sitt spår, och under det andra sprutningssteget kommer enhetens läge att sty- ras genom att den första höljesdelen med inneliggande kärntråd styrs i den för detta ändamål speciellt utformade rännan i den på ritningen övre verktygsdelen 12.In the first spraying step the position of the unit will be controlled by controlling one half of the core wire in its groove, and in the second spraying step the position of the unit will be controlled by controlling the first casing part with embedded core wire in the groove specially designed for this purpose. the upper tool part 12 in the drawing.

Om den tilltänkta kunden, t.ex. en tillverkare av mobil- telefonapparater så önskar kan man, såsom visas i fig. 3, som ett sista steg förse antennenheten med en på lämpligt sätt utformad skyddsknopp, företrädesvis under insprutning av plas- ten i en kombinerat axiell och radiell riktning, så att man uppnår en för bästa möjliga fyllning gynnsam rotationsrörelse och turbulens hos plastmassan.If the intended customer, e.g. a manufacturer of mobile telephones as desired, as shown in Fig. 3, the antenna unit can be provided as a final step with a suitably designed protective knob, preferably during injection of the plastic in a combined axial and radial direction, so that achieves a rotational movement and turbulence of the plastic mass favorable for the best possible filling.

Fackmannen inser, att man vid lämpligt tillfälle, före- trädesvis efter fullbordandet av det andra steget av höljets sprutning, i samband med att verktyget åter sluts för sprut- ning av den visade knoppen, avklipper kärntrådet, t.ex. i det i fig. 3 visade planet K.Those skilled in the art will appreciate that at the appropriate time, preferably after the completion of the second stage of spraying of the casing, in connection with the tool being closed again for spraying the shown bud, the core wire is cut, e.g. in the plane K shown in Fig. 3.

Claims

5,511,701 PATENT CLAIMS

A method of manufacturing an antenna unit, comprising a preferably resilient, wire or tubular, metallic core (10) and a fully or partially enclosing, sprayed, insulating housing, using a spraying tool which is divisible into a dividing plane (D) containing a longitudinal, central axis line through the core, characterized in that the insulating casing is sprayed in at least two steps, namely a first step, during which the core is provided for the most part by spraying with a first housing part (15) in the form of a half-tube cylinder, which preferably has a substantially uniform wall thickness, has side walls (16) lying in said dividing plane and end walls (17A, 17B) lying transversely to the axis line of the housing, while the other part of the core rests in a mold cavity part (11B) adapted to the shape of the core and is supported by this mold cavity part, that the core with the first casing part sprayed on it is advanced axially a distance corresponding to the n the length of the first casing part (15), and a second step, during which the still uncoated part of the core (10) is for the most part of the length of this part, also by spraying provided with a second casing part (18) complementary to the first-mentioned casing part ) in the form of a half-tube cylinder, which tube-tree has a substantially uniform wall thickness, has side walls lying in said dividing plane and end walls lying transversely to the axis of the housing, while the core (10) together with the first housing part (10) sprayed on it 15) rests in a second mold cavity part (19) adapted to the shape of this first part and is supported by this mold cavity part.

Method according to claim 1, characterized in that the second sprayed casing part (18), by corresponding design of the mold cavity part intended for this casing part, is given a smaller axial length than the first sprayed casing part. 511 701 6

Method according to claim 1 or 2, characterized in that, preferably by combined radial and Vaxial injection, so that some turbulence and rotation of the injected mass occurs, during a third injection step the antenna unit is provided with a knob (20), lying in a mold cavity around the top of the core and in intimate contact with at least the end of the core and the first sprayed casing part.

A tool for manufacturing an antenna unit in the manner specified in claim 1, which antenna unit comprises a preferably resilient, wire or tubular, metallic core and a fully or partially enclosing, sprayed, insulating housing, using a spraying tool, which is divisible into a dividing plane (D) containing a longitudinal, central axis line through the core, characterized in that the tool is made with two different mold cavities, namely a first mold cavity (11A), in which the core in a first step to the the part of its length by spraying is provided with a first casing part (15) in the form of a half tube cylinder, which preferably has a substantially uniform wall thickness, has side walls lying in said dividing plane and end walls lying transversely to the axis of the casing, while the core (10) the other part rests in a mold cavity part (11B) adapted to the shape of the core and is supported by this mold cavity part, as well as a second mold cavity, axially at a distance from the first mold cavity part, in which the still uncoated core part to a greater of this part's length, likewise by spraying is provided with a second, part part (18) complementary to the first-mentioned casing part in the form of a half tube cylinder, which tube has substantially uniform wall thickness, has side walls lying in said dividing plane and end walls lying transversely to the axis line of the casing, while the core together with the first casing part sprayed on it rests in a second mold cavity part (19) adapted to this first part and is supported by this mold cavity part.

Tool according to claim 4, characterized in that the tool has a special mold cavity for receiving the outer end of the core for forming a protective knob (20) thereon, preferably in intimate contact with at least the end of the core and the first injected the casing part.

6. A tool according to claim 4 or 5, characterized in that the tool has at least one further mold cavity, lying parallel to the other mold cavities, at some distance from them and in the same mold division plane, namely for spraying a casing on a further antenna conductor, in parallel with other conductors to form a so-called dual antenna. I. lll: “i M