Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q11/00—Electrically-long antennas having dimensions more than twice the shortest operating wavelength and consisting of conductive active radiating elements
  • H01Q11/02—Non-resonant antennas, e.g. travelling-wave antenna
  • H01Q11/08—Helical antennas
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q1/00—Details of, or arrangements associated with, antennas
  • H01Q1/005—Damping of vibrations; Means for reducing wind-induced forces
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q1/00—Details of, or arrangements associated with, antennas
  • H01Q1/36—Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewith
  • H01Q1/362—Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewith for broadside radiating helical antennas

Definitions

• the invention is based on a method for producing a helical antenna according to the preamble of claim 1 and on a helical antenna according to the preamble of claim 10.
• a helical antenna is e.g. known from DE-OS 38 22 664.
• Such antennas are usually produced as follows: a glass fiber bundle is impregnated with a hardenable casting resin, hardened into a glass fiber rod and then subjected to machining for precise shaping. The glass fiber rod already has the length intended for later use. The wire winding then passes through one
• the inventive method for producing a helical antenna with the characterizing features of Claim 1 has the advantage that the glass fiber rod is produced without machining. Another advantage is that the method according to the invention is suitable for producing antennas of any length or several antennas in one piece.
• thermoplastically processable thermoset as the connecting compound, since this material is particularly well suited for extrusion and subsequent curing.
• antennas with any directional characteristics and frequency characteristics can be produced by the wire-shaped, electrically conductive guide element being wound onto the glass fiber rod in different pitches, winding densities or winding directions.
• Fixing the electrically conductive conductor element on the glass fiber rod by means of a lacquer or adhesive has the advantage that the conductor element is prevented from slipping on the glass fiber rod, thereby guaranteeing constant antenna properties.
• the aerodynamics of the antenna can be improved, which is particularly the case when it is used for vehicle antennas affects.
• the winding creates an air flow that significantly reduces the noise generated by the antenna when driving.
• Glass fiber rod has the advantage that a reliable electrical and mechanical connection of the connection contacts to the conductor element takes place with the least effort.
• the helical antenna according to the invention with the characterizing features of claim 10 has the - -
• FIG. 1 shows an extruder for producing the glass fiber rod
• FIG. 2 shows an illustration of the helical antenna in various production stages
• Figure 3 shows a helical antenna with an additional, electrically non-conductive winding.
• an extruder 6 which has a rotationally driven screw conveyor into which a plurality of glass fibers 4 are introduced together with a plastic, hardenable connecting compound 5.
• the drive of the screw conveyor penetrates the plastic, hardenable connecting compound 5 into the spaces between the glass fibers 4.
• the glass fibers 4 with the connecting compound 5 are guided by the screw conveyor into a nozzle through which the glass fibers 4 with the connecting compound 5 in the form of a glass fiber rod 1 emerge.
• the glass fiber rod 1 is given a defined outer shape by the nozzle of the extruder 6, which no longer has to be machined.
• the still plastically deformable fiberglass rod 1 is cured behind the extruder 6. This happens, for example, through exposure to heat.
• the hardened glass fiber rod 1 is helically wrapped with a wire-shaped, electrically conductive conductor element 2. It is preferably provided that the wound-on conductor element 2 is fixed on the glass fiber rod 1, for example with a lacquer or also with an adhesive layer.
• a spindle feeding the conductor element 2 can be guided around the glass fiber rod 1, but the glass fiber rod 1 can also be rotated about itself while it is carrying out an axial movement.
• the wrapped glass fiber rod 1 is then covered with an insulating material 3. This can be done in particular by a further extrusion process.
• the insulating fiber cover 3 protects the glass fiber rod 1 with the wire-shaped, electrically conductive conductor element 2 wound thereon from environmental influences and also mechanical influences. In this case, the fixing of the position of the conductor element 2 on the glass fiber rod 1 is also exerted by the insulating material cover 3, so that there is no need for fixing with varnish or an adhesive layer.
• the wrapped glass fiber rod 1 with insulating material 3 can be produced in particular in any length with this method. To complete an antenna from this wrapped glass fiber rod 1, it is simply cut to a desired length and the insulating material cover 3 is removed for contacting at the points at which one or more electrical connection contacts 7 are to be attached.
• the Connection contact 7 in the form of a connection element squeezed onto the glass fiber rod 1 with the wire-shaped, electrically conductive conductor element 2 wound thereon.
• helical antennas in endless form, in particular for use as vehicle antennas, and to determine the length subsequently to method steps 1 to 4.
• the division of the endless helical antenna into individual antennas of finite length can in particular only be carried out shortly before assembly by the customer.
• FIG. 3 shows the antenna previously shown in FIG. 2, which here has been provided with an additional, electrically non-conductive winding 8. The numbering from FIGS. 1 and 2 was otherwise retained.
• the winding 8 is arranged above the wire-shaped, electrically conductive conductor element 2 and below the insulating sleeve 3 and has a higher pitch than the wire-shaped, electrically conductive conductor element 2.
• the winding 8 is arranged between the glass fiber rod 1 and the wire-shaped, electrically conductive conductor element 2 or even above the insulating sleeve 3.
• the incline can also be freely selected.
• the material for the winding 8 is, for example Polyamide round wire suitable, which can be applied, for example, by extrusion onto the glass fiber rod 1 without or with the wire-shaped, electrically conductive conductor element 2 wound thereon. For this purpose, it is provided either to rotate the extrusion nozzles for the winding 8 or the glass fiber rod 1 about its longitudinal axis, or to do both.
• the winding 8 can therefore also be produced endlessly, as a result of which the endless character of the production of the antenna shown in FIG. 1 is maintained.
• the winding 8 is arranged here together with the wire-shaped, electrically conductive conductor element 2 under the insulating sleeve 3.
• the contour of the winding 8 presses through the insulating sleeve 3, so that its
• Outer contour has a helical interference. If an antenna designed in this way is moved in air, the winding 8 creates air swirls which reduce resonance whistling of the antenna.
• the winding 8 can also be made of electrically conductive materials and insulated from the wire-shaped, electrically conductive conductor element 2, e.g. through the insulating sleeve 3.
• the insulating sleeve 3 can also be omitted entirely, only over the wire-shaped, electrically conductive conductor element 2, over both together or such an insulating sleeve over the wire-shaped, electrically conductive conductor element 2 and the winding 8.
• the cross sections of the outlet openings of the extrusion nozzles, both for the glass fiber rod 1 and for the winding 8, can be round, oval, star-shaped or in some other form.

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Applications Claiming Priority (2)

Publications (1)

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Family Applications (1)

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Cited By (1)

Families Citing this family (1)

Citations (6)

• 1995
  • 1995-05-09 DE DE1995116888 patent/DE19516888A1/de not_active Withdrawn
• 1996
  • 1996-03-27 WO PCT/DE1996/000571 patent/WO1996036087A1/de active Application Filing
  • 1996-04-09 TW TW85104108A patent/TW311290B/zh active

Patent Citations (6)

Non-Patent Citations (2)

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