KR19990014894A - How to Block Cables or Conductor Bundles - Google Patents

Abstract

Induction heating of the wires in the device or wire bundles produces heat to melt the blocking material to flow and block the space within the device and shrink the plastic sleeve around the blocked area. The blocked material or sleeve, but not both, can be inductively heated.

Description

How to Block Cables or Conductor Bundles

Blocking that prevents fluid from flowing along the cable or wire bundle is known, for example, from US-A-4972042 (RK310), and the heat-melt adhesive is placed in contact with the conductor (usually insulated), and heat The shrinkable sleeve shrinks around the cable or bundle portion carrying the adhesive. The heat applied to shrink the sleeve is generally by means of a hot air gun or flame torch, whereby the adhesive melts and flows between and around the conductors, assisted by the shrinking action of the sleeve to block the cable or bundle thereof. do. These well known blocking procedures have to be able to melt and flow at relatively low temperatures below 100 ° C. and have the limitations that can be obtained inside the sleeve without overheating or damaging the sleeve. This may limit the temperature that can be tolerated by blocked cables or bundles in subsequent services.

Other cable blocking systems are described in WO-A-94 / 24837 (MP1474), in which particles of ferromagnetic material are fused into the hot melt blocking adhesive, and the particles inductively couple with other magnetic fields upon which the cable carrying the adhesive depends. It is formed. By final induction heating of specially formed photomagnetic particles, the adhesive melts and flows to block the cable. The heat-shrinkable sleeve has photomagnetic particles that heat to a reduced temperature when exposed to a magnetic field. This system alleviates the already mentioned limitations of external heating.

The present invention relates to a method of blocking a cable or conductor bundle.

The present invention also avoids external heating, which may be expensive or otherwise undesirable in some circumstances, while reducing or eliminating the need for specially formed photonic particles.

Accordingly, the present invention provides, in the broadest aspect, a method of blocking a cable or conductor bundle comprising: (a) applying a body of heat-flowable blocking material to a portion of the cable or bundle to be blocked; (b) selectively applying a cover around at least a portion of the cable or bundle to be blocked, wherein the blocking material and cover (if any) are (i) non-conductive, nonmagnetic and non-inductive Or (ii) if no conductor is present, the blocking material has a condition that can be inductively heated, one of which can be inductively heated and the other can be inductively heated; And (c) applying a alternating magnetic field that inductively couples the conductor and / or the blocking material that can be inductively heated to the cable or bundle to a temperature at which the blocking material flows to block the cable or bundle. Inductively heating the blocking material.

In a more specific aspect, the invention provides a method of blocking a cable or bundle of metal conductors, the method comprising: (a) non-magnetic and non-magnetic heat-flowable blocking of the body to a portion of the cable or bundle to be blocked; Applying a substance; And (b) applying an alternating magnetic field that inductively couples the conductor to the cable or bundle, thereby inductively heating the conductor to a temperature that causes the blocking material to flow to block the cable or bundle.

The present invention is based on the surprising discovery that sufficient heating can be produced in the conductor without the addition of an inductively heated adduct in the blocking material so that the blocking material can be melted and flowed to obtain a satisfactory block. I put it. The present invention has the advantage of being equally applicable when the cover is provided at least around the portion of the cable or the blocked bundle. The cover is an elastomer and is arranged to compress at least part of the cable or bundle before and during the flow of the blocking material.

It is even more surprising that the cover becomes a heat-shrinkable article that shrinks around the portion of the cable or bundle. With the new use of heat generated by conductors inside cables or bundles, blocking materials of higher melting or softening temperatures can be used without damaging the heat-shrinkable cover. Optionally, the heat-shrinkable article can carry inductively heatable additives in the inner lining of the adhesive or other material such that the blocking material is dependent on the heat generated inside the conductor.

The melting or softening point of the blocking material, and the critical reduction temperature of the heat-shrinkable cover, if present, is a temperature that can be produced by induction heating of the conductor without damaging the electrically insulating material carried by the conductor. It may be chosen to adjust appropriately. For example, automotive devices up to 100 wires made of 0.25-6 mm ² diameter PVC-insulated wire with a temperature rate of 105 ° C. (T2 ratio) have a softening temperature of 85 ° C. and a recovery temperature below 100 ° C. Using an induction generator operating at a frequency between 0.2 and 1 MHz with a 2.5 kW power and using a flow temperature of 110 ° C. with a heat-shrinkable sleeve of. Low-temperature-ratio (ie, T1 = 70 ° C.) PVC is a high-melt adhesive with a flow temperature of 80-90 ° C. with a softening point of 50-60 ° C. and a heat-shrinkable tubing with a recovery temperature lower than 90 ° C. Need to use

As another blocking adhesive for wires with a low insulating softening point in the range of 50-60 ° C., the molten adhesive can be replaced with a frankincense material such as polyisostyrene. During installation, heat from the wire softens the frankincense and increases the flow of the frankincense. Under these circumstances, a heat-shrink sleeve or rubber sleeve can be used to harden the block.

The present invention is particularly applicable to conductors composed of fine metal filaments, the geometry of which is intended to be inductively coupled to the magnetic field to be applied, for example copper wires each having many strands of 75-150 micrometers. It is configured to have a diameter. These are wandered together to make the wire and can be used depending on the last cross-sectional area of the wire from 7-50 strands. Typical materials are copper and may be plated with nickel, tin or silver. However, other conductor materials can be used, such as nickel or aluminum.

Other suitable blocking material may be used to flow at a temperature that may be generated by the conductor and then solidify sufficiently to block the cable. Preferred high melt adhesives are those already described in US-A-4972042, the disclosure of which is incorporated by reference.

Heat-shrinkable covers will be described in US-A-4972042 or WO-A-94 / 24837, the disclosure of which is incorporated by reference.

When an elastomeric cover is used, it can be made, for example, of EPDM rubber, polychloroprene rubber, polyester rubber or natural rubber. The size and shape of the cover becomes insignificant if the assembly is sufficiently pushed into the position forming a suitable block in the cable or bundle.

Specific examples of this aspect of the invention will be described in detail in the following description.

Example 1

A wire bundle consisting of 60 1.5 mm ² copper conductors of 100 micron strands with a 0.5 mm jacket of PVC insulation proportional to T2 (105 ° C) is applied to Rayblock 85 polyamide heat applied in the form of a 4, 5 channel comb profile. Blocked using melt adhesive. These wires are secured to each channel of the comb with up to three wires per channel. The external heat shrink tubing was 40 mm long of the TAT-125 heat shrink tubing with a diameter of 25 mm. A 250 kHz induction heater was used to form the field in a 5 turn 50 mm diameter spiral coil. The coil operates at 150 amps providing a field strength of 750 amps, the cable harness blocked within 60 seconds and the maximum temperature reached in the bundle is 130 ° C.

Example 2

The bundle of 100 wires was sealed using 6 rayblock 85 adhesive combs with 6 channels as described above, and the heat shrink tubing was 50 mm long with a 75 mm diameter TAT-125 tubing. The sealing time is 45 seconds.

Example 3

The bundle described in Example 1 was used in place of heat shrink sleeving, with the exception of the 40 mm sleeve of 15 mm diameter cloproprene rubber of the 60IRHD device. Under the same conditions as the example, the sample blocked within 45 seconds.

Example 4

The bundle described in FIG. 1 was blocked using poly isobutyrene frankincense (3 M's EMB-45R) with the cloproprene rubber sleeve described in Example 3. During the time the frankincense flowed from underneath the elastomeric tubing to terminate the sealing process, the sample was heated in an induction heater for 60 seconds.

Example 5

The bundle described by Example 1 was a polyamide adhesive comb block 105, except that the insulator on the wire was a latticed 62 polyester wire with a temperature ratio of T3 (125 ° C.). The heat shrink sleeve was Layette ATUM 24/8 ™ and the bundle was heated for 90 seconds and sealed to a maximum temperature of 160 ° C. recorded in the bundle.

Another aspect of the invention provides a method of blocking a cable or conductor bundle, wherein the blocked material is inductively heatable, the cover is non-inductively-heatable. The present invention relates to a cover comprising (a) a cable or bundle of (i) a body of inductively-heatable and heat-flowable blocking material and (ii) a non-inductively-heatable cover at least around the cable portion or bundle being blocked. Inductively heating the blocking material to a temperature such that it flows and blocks the cable or bundle by applying an alternating magnetic field that inductively connects the portion of the cable or bundle with the block material. Include.

In this other method, the conductors can be inductively heated as before, or can be, for example, optical fibers, which can be inductively heated.

When the cover, which can be inductively heated, becomes heat-shrinkable, it will shrink at temperatures facing the result of induction heating and / or final flow of blocking material.

When the cover is an elastomer, it will be installed to press and block a portion of the cable or bundle, at least before and during the flow of the blocking material.

Suitable inductively heatable blocking materials for this method can be selected, for example, from those described in WO-A-9424837 (MP1474). For blocking materials that can be inductively heated in all aspects of the present invention, this becomes desirable in some cases using curable materials, such that the viscosity increases after flowing and blocking the cable or bundle. This enhances the blocking effect and reduces the risk of blocking becoming inefficient after subsequent temperature changes. The curable blocking material may be selected from those comprising interleaved sheets, each containing a separate reactive component of the curing system described in WO-A-9527764 (B247), the disclosure of which is incorporated by reference. .

Claims (10)

A method of blocking a cable or conductor bundle, (a) applying a body of heat-flowable blocking material to a portion of the cable or bundle to be blocked; (b) selectively applying a cover around at least a portion of the cable or bundle to be blocked, wherein the blocking material and the cover (if present) are (i) nonconductive, nonmagnetic and non-inductive Or (ii) if no conductor is present, the blocking material has a condition that can be heated inductively, one of which can be inductively heated and the other can be inductively heated, ; And (c) applying the alternating magnetic field that inductively couples the conductor and / or the blocking material that can be inductively heated to the cable or the bundle at a temperature at which the blocking material flows to block the cable or bundle; And / or inductively heating the blocking material. The method of claim 1, wherein the conductor is metallic, the method comprising: (a) applying a body of non-magnetic, nonmagnetic, non-magnetic heat-flowable blocking material to a portion of the cable or bundle to be blocked; And (b) inductively heating the conductor to a temperature such that the blocking material flows to block the cable or bundle by applying an alternating magnetic field that inductively couples the conductor to the cable or bundle. A method of blocking a cable or conductor bundle, characterized in that. The method of claim 1, wherein (a) the cable or bundle to be blocked is (i) as a body of inductively heated and heat-flowable blocking material and (ii) at least a portion of the cable or bundle to be blocked. Applying a cover to the inductively heated cover; And (b) inductively heating the blocking material to a temperature such that the blocking material flows to block the cable or bundle by applying an alternating magnetic field that inductively couples the blocking material to the cable or bundle portion; Method of blocking a cable or conductor bundle comprising a. The method of claim 1 or 2, wherein the cover (preferably non-conductive and non-magnetic) is provided around at least a portion of the cable or bundle to be blocked. . The method of claim 3 or 4, wherein the cover is a heat-shrinkable article that shrinks around the cable or bundle portion. The article of claim 5, wherein the heat-shrinkable article is reduced in temperature to (i) inductively heating the conductors and / or blocking material, and / or (ii) causing a flow of the blocking material. Characterized in that the cable or conductor bundle is blocked. The method of claim 3 or 4, wherein the cover is elastomeric and is arranged to compress the cable or bundle portion before and during the flow of the blocking material. 8. A method according to any one of the preceding claims, wherein the conductor can be inductively heated and inductively heated by the magnetic field. The method of any one of claims 1 to 8, wherein at least a portion of the conductor can be heated inductively. 10. The method of claim 9, wherein the non-inductively heated conductor is optical fiber.