CN213210550U - Signal transmission optical cable used in severe environment - Google Patents

Abstract

The utility model discloses a signal transmission optical cable that uses under adverse circumstances, including single or a branch of optic fibre that extends in the tubular metal resonator to and insert the netted ceramic sheath between optic fibre and tubular metal resonator. The metal tube holds the optical fiber in place by compressing the sheath.

Description

Signal transmission optical cable used in severe environment

Technical Field

The utility model relates to an optical cable field, concretely relates to signal transmission optical cable who uses under adverse circumstances. The utility model provides a hostile environment is the higher environment of vibration rank and temperature.

Background

It is well known that high levels of vibration can compromise the mechanical strength of the cable and that high temperatures can damage the optical cladding of the cable, thereby degrading the transmission performance of the cable.

Optical cables for use in harsh environments, the individual optical fibers or bundles of optical fibers of which are usually mechanically supported by a sheath (made of organic or plastic material).

Such a protective sheath has a low bending stiffness. Therefore, when designing an optical information path having a high-frequency vibration mode, a large number of fixing points must be provided along the cable to ensure that the distance between the fixing points is short. The natural frequency of the cable is beyond the excitation frequency of the engine, so that the cable is prevented from resonating, and the mechanical stress borne by the cable is low, thereby prolonging the service life of equipment. However, this device is very expensive due to the high number of fixing points (usually consisting of rings).

In addition, the use of plastic jacketing is severely limited by high temperatures. Most conventional materials, such as polymeric materials, have a use temperature limit of about 260 c or less.

In order to solve the problems of mechanical rigidity and high temperature resistance, it is common practice to fix the optical fibers in a rigid or corrugated metal tube, i.e. a tube consisting of a plurality of hinged elements, having a certain deformability.

However, in such devices, the optical fiber must be mounted inside the metal sheath with minimal play to reduce vibrations inside the sheath. To further reduce the play, a jacket lining made of ceramic wool may also be wound on the optical fiber during assembly.

However, such a jacket liner can only be used in a short length (30 cm). Furthermore, even if the play is reduced by adding a jacket lining, the supporting effect is not very good.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a signal transmission optical cable who uses under adverse circumstances to solve the problem that proposes among the above-mentioned background art.

In order to achieve the above object, the utility model provides a following technical scheme:

the utility model discloses a signal transmission optical cable that uses under adverse circumstances, including single or a branch of optic fibre that extends in the tubular metal resonator to and insert the netted ceramic sheath between optic fibre and tubular metal resonator. The metal tube holds the optical fiber in place by compressing the sheath.

The utility model discloses in the high temperature environment (like the engine of aircraft engine or rocket launcher): the temperature can reach 250-1000 ℃, and the vibration root mean square can reach 200g in the frequency range of 5-20000 Hz.

Drawings

Fig. 1 is a schematic cross-sectional view of the present invention.

Reference numerals: a metal tube (1); a ceramic sheath (2); an optical fiber (3).

Detailed Description

The present invention will be further explained with reference to the accompanying drawings.

The cable shown in the figure comprises a metal tube 1, a ceramic sheath 2, in which a single or a bundle of optical fibres 3 extends.

The metal tube 1 is corrugated and made of stainless steel, nickel based material, or super alloy (e.g. inconel or a230 hastelloy).

The ceramic sheath 2 is net-shaped and made of zirconium dioxide, aluminum oxide, magnesium oxide, silicon dioxide, boron oxide and other materials. For example, ceramics made of silica, boron oxide, and alumina may be used.

The optical fiber 3 is made of glass (quartz, silica) or plastic.

During the manufacture of the above-described cable, the metal tube 1 is reduced in diameter by shrinkage and cold working. Then, the ceramic sheath 2 compresses the optical fiber 3, thereby mechanically fixing the optical fiber 3. The mesh structure of the jacket 2 prevents the optical fibers from being damaged during compression.

For example, for a cable containing a single optical fiber having a diameter of 400 μm, 3.5mm may be used for the outer diameter of the tube 1, and 0.5mm may be used for the thickness of the tube.

The above structure has many advantages. Firstly, the mechanical strength of the optical fiber in the optical cable is guaranteed, and the optical fiber is easier to be optically aligned by compression; secondly, the optical cable with higher hardness is provided and can be placed on an engine after cold forming; third, the cable is capable of withstanding high temperatures and vibration environments and can operate for hundreds of thousands of hours. The aircraft engine has been tested; fourthly, deformation can be performed according to an engine path; fifth, the sealed optical cable may be manufactured by welding the metal tube 1; sixth, securing the optical fiber inside the jacket and tube allows for easier polishing of the end of the cable.

Claims (3)

1. A signal transmission cable for use in harsh environments, comprising: comprises a single or a bundle of optical fibers (3) extending inside a metal tube (1), and a reticulated ceramic sheath (2) interposed between the optical fibers and the metal tube; the metal tube holds the optical fiber in place by compressing the sheath.

2. A signal transmission cable for use in a harsh environment according to claim 1, wherein: the optical fiber (3) and the reticular ceramic sheath (2) are arranged inside the metal tube (1); the metal tube (1) is formed by shrinkage and cold working.

3. A signal transmission cable for use in a harsh environment according to claim 1, wherein: the optical cable is suitable for application of engines of aircraft or rocket transmitters in high temperature environments.

Images