DE7738998U1 - Electric cable for mains operation - Google Patents

Description

^ Patent Attorneys Dip] -Jng. C U rt Wallach

, · '; Dipl .-! Ng. Günther Koch

Dipl.-Phys. Dr Tino Haibach

Dipl .-! Ng. Rainer Feldkamp

D-8000 Munich 2 ■ Kaufingerstraße 8 · Telephone (0 89) 24 02 75 ■ Telex 5 29 513 wakai d

Date- December 21, 1977

Our lines: ^{16 O} 98 "V Yes

Wolf Devices GmbH., Betzdorf / Sieg

Electric cable for mains operation

The invention relates to an electric cable for Netzbe ^ rieb with a relatively rigid plastic jacket, which acts as a tension coil spring is formed and in the relaxed state rests with its turns essentially against one another.

Such electrical cables have the advantage that they are used, for example, for lawnmowers, hedge trimmers or the like. on the required (shortest) length between power source and place of work can be extended and when approaching the Cause an automatic shortening of the power source. This avoids that the electrical cable in uncontrollable Loops are on the floor, which is particularly important when using Electric lawnmowers are guaranteed because the cable is often not visible in deep grass. Such an electric cable also does the use of automatic or manually operated winding devices is superfluous because it is relaxed State automatically occupies the smallest possible space. With the previously known electrical cables of this type, attempts have been made to to design the structure so that the outer diameter of the

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Cable does not significantly exceed the outer diameter of conventional cables in order to ensure that they are used Cables can be used in conjunction with conventional device plugs or device sockets. This inevitably has led to the fact that the insulation layer surrounding the isolated individual conductors is omitted or by c inen relatively thin hose cover had to be replaced, so that the plastic jacket also has the task of protective insulation came to. However, it has been shown that this dual task cannot be fulfilled by a plastic jacket, which because of the required suspension properties must be set extremely hard. This Orunde becomes the well-known Electric cables with return spring properties do not meet the need for security and the invention is therefore the The underlying task is an automatically curling one To create safety cables for the use of electrical appliances outdoors that meet all safety needs is equivalent to.

According to the invention, this object is achieved in an electric cable of the type mentioned in that the A plastic jacket that exerts a spring effect is approved according to the VDE regulations for devices to be used outdoors Enclosed rubber hose line e.g. according to NMHöu or Ho5RN.

Because the plastic sheath to generate the required The electrical cable according to the invention naturally has a spring force that cannot fall below a certain minimum wall thickness a larger diameter than the commercially available security cables, but this in view of the advantages achieved can easily be accepted. The attachment can then be specially molded or vulcanized on trained plugs take place. According to a preferred embodiment

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Implementation of the invention, however, makes the use of specially adapted plugs and sockets superfluous, the electric cable was stripped of a short piece of a few centimeters from the plastic sheath at both ends, So that the normal rubber cable is exposed in these end sections, which can be attached to the standardized ones by all conventional means Cteokern or sockets can be attached.

A major advantage of this setback of the spring jacket at the two ends also has the advantage that at these ßellen the elasticity of the cable is maintained so that the cable can be adapted at the end points of the required movement of the powering electrical devices without da8 the operator would have to overcome the spring force with a necessary pivoting movement of the device. To be overcome only need the spring return force of the coil spring, while at the ends the ones required for proper operation of the devices Mobility is guaranteed.

This also prevents the rigid plastic jacket from breaking at the ends due to excessive stress, which is the case with the previously known cables was to be feared. This increases the safety function significantly. Through the invention If it is also possible to equip the plug or the coupling in a known manner with a coating that protects against water, βο that a cable can be created, which not only is safer against punctures, but also has protection against penetrating water.

An embodiment of the invention is illustrated below described in the drawing. In the drawing show:

Fig. 1 is a shearful partial view of an inventive design Electrical cables,

Fig. 2 on a larger scale a cross section of the erfindungsgeniaß

trained electrical cable.

Electric cable 1 has three conductors 2, each with one .iers <· are also provided with 3 and shared by one !! hose 4 is enclosed, as required by the regulations. This safety hose line, enclosed by a plastic jacket 5, which is very hard; estellt and accordingly has pedering properties. Plastic jacket is made in such a way that it has the shape τ has helical spring whose turns in the relaxed and lie essentially next to one another (in the illustration in FIG. 1, the turns are already a little apart).

1, the rubber hose jacket 4 is exposed at the two ends of the cable because the plastic jacket 5 is offset so that the elasticity given by the hose line 6 in the area of the plug 6 or the manure 7 is real.

Protection claims:

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Claims (1)

Protection claims Electric cable for network operation with a relatively rigid Xunst- ; off coat made of a springy material known as a tension coil spring is formed and in the relaxed state with its turns ι rests essentially against one another, characterized by ge e t that the plastic jacket (5) is approved according to the VDE regulations for devices to be used outdoors immi hose line (4) ytiach NMHöu or Ho5RN encloses. Electric cable with connection plug or connection socket on its iden according to claim 1, characterized in that ß the plastic jacket (5) on the two parts adjacent to the plug (6) and the socket (7) is set back, so ß the rubber hose jacket (4) is exposed. 7738998 04/06/78